Compare elemental calcium in mg per labelled daily serving, not compound or tablet weight. Vitamin D, magnesium and other actives are recorded separately. The amount is what the label states, not a dose-adequacy rating. Where directions give a range, the range is shown and daily cost uses the low end (no directions: one unit a day). Read the dose guide ↓

Calcium product comparison
#	Product	Calcium form	Daily dose	Price/day	Testing	Score
1	Alpha01 Calcium Carbonate 400mg – TabletsAlpha01180 tablets	CarbonateTabletCalcium carbonate	400 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.05per day£8.99 per packBuy Nowon Amazon	Testing evidence Evidence status Verified independent evidence Manufacturer statement Manufacturer page shows a 'CERTIFICATIONS & LAB TESTS' section for this product with 'Heavy Metals Testing' and 'Microbial Contaminants Testing' for batch LC260172, and the linked report is a J.S. Hamilton Baltic test report for 'Alpha 01 - Calcium carbonate, 400mg'. Laboratory SIA "J.S. HAMILTON Baltic" Certification body Not recorded Batch LC260172/022029 Batch-specific report Recorded Report date Not recorded Evidence checked 2026-09-27 09:48:29 Certificate of analysis ↗ Laboratory report ↗ Manufacturer testing page ↗	Why this score? Testing & evidence 19/20 Ingredient/formulation quality 23/25 Value 20/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
2	Horbäach Horbaach Calcium Carbonate 800mg – TabletsHorbäach180 tablets	CarbonateTabletCalcium carbonate	800 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.11per day£9.99 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Horbaach’s own site says: “Laboratory Tested” and “We constantly source the best ingredients worldwide, test each individual product to ensure it meets our strict Quality Assurance Standards.” Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 10:09:26 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 18/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
3	Sunshine Nutrition Calcium & Vitamin D3 800mg – TabletsSunshine Nutrition90 tablets	Carbonate Calcium + DTabletCalcium carbonate	800 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.12per day£5.49 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Sunshine Nutrition’s About Us page says: “All inbound raw materials are tested in-house…” and “After blending and bottling, we test the finished goods at our in-house labs to verify that what’s on the label is what’s in the bottle and that our products are free of heavy metals, pesticides, and other contaminants.” Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:52:02 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 17/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
4	Simply Supplements Calcium & Vitamin D3 1000mg – TabletsSimply Supplements180 tablets	Carbonate Calcium + DTabletCalcium carbonate	500–1,000 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.06per day£11.29 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Simply Supplements’ About page says: “Laboratory Tested — We provide certificates of Analysis that validate the purity and level of active ingredients within each product and independently tested.” The product page itself also says only that it is “Manufactured in the UK to GMP standards,” which is not an independent testing/certification claim. Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:56:18 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 20/20 Dose transparency 11/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
5	Horbäach Horbaach Chewable Calcium & Vitamin D3 800mg – ChewablesHorbäach120 chewables	Carbonate Calcium + DChewableCalcium carbonate	800 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.13per day£7.99 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Manufacturer site says: "We put our products to the test, ensuring maximum potency from each formula we produce" and "we ... test each individual product to ensure it meets our strict Quality Assurance Standards." Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:55:06 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 17/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
6	Lindens Calcium 800mg – TabletsLindens100 tablets	Carbonate Calcium + DTabletCalcium carbonate	800 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.14per day£6.83 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Lindens’ site says: “We are proud to hold ISO 9001 Certification” and on the About Us page: “British Standards Institution: ISO 9001:2015 Quality Management Systems, (Certificate no. FS 657303).” This is a general quality-system accreditation claim, not a product-specific third-party test/certification for the calcium tablets. Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 10:02:27 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 16/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
7	Ov OXFORD VITALITY Oxford Vitality Calcium & Vitamin D 800mg – TabletsOv OXFORD VITALITY120 tablets	Carbonate Calcium + DTabletCalcium carbonate (2,222 mg)	800 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.15per day£5.99 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Amazon listing and manufacturer site say the product is 'quality controlled' / 'quality assured' and 'carefully manufactured' and the product page says 'At Oxford Vitality, our Calcium and Vitamin D tablets...' but I did not find any independently verifiable third-party test report or certification for this specific product. The manufacturer also says on its product page: 'At Oxford Vitality, our Calcium and Vitamin D tablets contain Vitamin D3...' and on the Amazon listing: 'TRUSTED UK QUALITY: Our products are expertly manufactured and packed in the UK using carefully selected ingredients and quality controlled processes.' Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:45:00 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 15/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
8	NutriVolv Calcium & Vitamin D3 500mg – CapsulesNutriVolv60 capsules	Carbonate Calcium + DCapsuleCalcium carbonate	500–1,000 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.06per day£3.79 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Amazon listing image/text shows the product is described as "Lab Tested"; NutriVolv product pages also show generic quality claims like "GMP" and "Non-GMO" but no independently verifiable COA or third-party registry entry was found for this specific calcium + vitamin D3 product. Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:50:46 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 19/20 Dose transparency 11/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
9	Zipvit Calcium & Magnesium 400mg – TabletsZipvit120 tablets	CarbonateTabletCalcium carbonate preparation	400 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.07per day£8.99 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Amazon listing and Zipvit product page both claim the product is "3rd Party Tested" / "independently tested for heavy metals" and the Zipvit product page also says "INDEPENDENTLY LAB-TESTED" and "SEE LAB RESULTS," but I did not find an actual COA/lab report or a certifying-body registry page confirming this specific product. Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 10:03:32 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 19/20 Dose transparency 15/15 Manufacturer transparency 6/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
10	Vitamaze – amazing life Vitamaze Calcium Tablets 800mg – TabletsVitamaze – amazing life180 tablets	CarbonateTabletCalcium carbonate (2,028.9 mg)	800 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.16per day£13.97 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Amazon listing/product images explicitly say 'Geprüfte Qualität / Certified Quality' and 'Die Vitamaze Calcium Tabletten wurden von einem führenden deutschen Analyseinstitut geprüft' (the image also shows a GBA-branded analysis document), but I could not independently verify a product-specific certificate or registry entry from the certifying/testing body itself. Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:59:07 Amazon listing (claim source) ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 15/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
11	New Leaf Products New Leaf Calcium 1000mg – TabletsNew Leaf Products120 tablets	Carbonate Calcium + DTabletCalcium carbonate (2,500 mg)	1,000 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.17per day£9.97 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Manufacturer site says: "To ensure the highest safety and quality, our products undergo rigorous testing for heavy metals and unwanted compounds during production" and Amazon listing says: "SAFETY & QUALITY - To uphold the highest standards of safety and quality, our products undergo post-production testing for heavy metals and other ..." Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 10:07:08 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 14/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
12	Zenement Calcium Citrate 306mg – CapsulesZenement120 capsules	Citrate Calcium + DCapsuleCalcium citrate (1,450 mg)	306 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.20per day£12.29 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Zenement’s product/collection pages market the product with claims like “Seal of Quality,” “strictest quality controls,” and the Amazon listing image says “Analyses certified by external laboratories,” but I did not find a public COA, lab report, or certifying-body registry entry for this specific product. Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 10:01:00 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 13/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
13	Neo-nutrition Calcium Citrate 300mg – CapsulesNeo-nutrition60 capsules	CitrateCapsuleCalcium citrate (1,200 mg)	300 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.33per day£9.99 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Neo Nutrition’s own ‘Our Process’ page says: ‘Every ingredient and finished product undergoes rigorous quality testing in our state-of-the-art laboratory. We test for purity, potency, and safety to ensure our products meet the highest standards.’ Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:47:51 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 12/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
14	Pure Encapsulations Calcium 450mg – CapsulesPure Encapsulations180 capsules	CitrateCapsuleCalcium citrate	450 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.60per day£35.75 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Manufacturer page says: "To ensure that all products meet the highest standards, our raw materials are scientifically tested before use, and every formula is tested to confirm its quality." Product sheet for Calcium (citrate) says only "Made with high-quality ingredients backed by verifiable science" and gives no product-specific third-party certificate or lab report for this item. Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:54:30 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 10/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
15	HealthAid Calcium Complete 800mg – TabletsHealthAid120 tablets	Mixed formsTabletCarbonate, citrate and pyruvate	800 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.15per day£8.89 per packBuy Nowon Amazon	Testing evidence Evidence status No public evidence located Manufacturer statement Not recorded Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 10:05:59	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 23/25 Value 16/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
16	Solaray Calcium Citrate 1000mg – CapsulesSolaray90 capsules	Mixed formsCalcium + DCapsuleCalcium citrate and calcium carbonate	1,000 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.68per day£14.99 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Manufacturer site says: "We source our own raw materials and triple-test every lot" and "15,000 tests per month verify ingredient potency and purity"; product page also says the facility is "certified by NSF" and that Solaray conducts testing in its ISO-accredited lab. Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:49:42 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 9/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
17	Higher Nature Icelandic Seaweed Calcium 260mg – CapsulesHigher Nature60 capsules	Other calcium saltCapsuleIcelandic seaweed (Lithothamnion)	260–780 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.20per day£11.95 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Manufacturer site says the product is "Third party tested for quality assurance" and the page also states "Our True Food standards ... Third party tested". Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:57:14 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 13/20 Dose transparency 11/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
18	Pure Encapsulations Calcium MCHA 750mg – CapsulesPure Encapsulations180 capsules	Other calcium saltCapsuleMicrocrystalline hydroxyapatite (MCHC), bovine	750 mgWithin typical rangeTypical: 300–1,000 mg/day	£1.23per day£73.85 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Manufacturer site says: "All raw materials and finished products are independently tested for purity and potency by our third-party laboratories" and the product page says the product is "made with high-quality ingredients backed by verifiable science." Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:43:51 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 23/25 Value 9/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
19	Natures Aid Calcium, Magnesium & D3 800mg – TabletsNatures Aid90 tablets	Mixed formsCalcium + DTabletCarbonate and citrate	800 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.17per day£7.50 per packBuy Nowon Amazon	Testing evidence Evidence status No public evidence located Manufacturer statement Not recorded Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 10:07:59	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 23/25 Value 14/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
20	Solgar Calcium Magnesium plus Zinc 1000mg – TabletsSolgar100 tablets	Mixed formsTabletCarbonate, citrate and gluconate	1,000 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.28per day£9.12 per packBuy Nowon Amazon	Testing evidence Evidence status No public evidence located Manufacturer statement Not recorded Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 10:10:16	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 23/25 Value 12/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
21	Solgar Calcium Citrate 1000mg – TabletsSolgar240 tablets	Citrate Calcium + DTabletCalcium citrate	1,000 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.33per day£19.99 per packBuy Nowon Amazon	Testing evidence Evidence status No public evidence located Manufacturer statement Not recorded Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 10:04:20	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 23/25 Value 11/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
22	Bolman Health Calcium Citrate 300mg – CapsulesBolman Health60 capsules	CitrateCapsuleCalcium citrate (1,200 mg)	300 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.37per day£10.99 per packBuy Nowon Amazon	Testing evidence Evidence status No public evidence located Manufacturer statement Not recorded Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:45:49	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 23/25 Value 11/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
23	Biocare Calcium Citrate 500mg – CapsulesBioCare90 capsules	CitrateCapsuleCalcium citrate	500 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.68per day£20.29 per packBuy Nowon Amazon	Testing evidence Evidence status No public evidence located Manufacturer statement Not recorded Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:46:30	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 23/25 Value 10/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
24	Vitabiotics Ultra Calcium & D 500mg – TabletsVitabiotics Ultra30 tablets	Not disclosedCalcium + DTablet	500–1,000 mgWithin typical rangeTypical: 300–1,000 mg/day	£0.12per day£3.49 per packBuy Nowon Amazon	Testing evidence Evidence status No public evidence located Manufacturer statement Not recorded Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 10:11:17	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 18/25 Value 18/20 Dose transparency 11/15 Manufacturer transparency 9/10 Label/ingredient transparency 8/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
25	G&G Vitamins Calcium Citrate 200mg – CapsulesG&G Vitamins120 capsules	CitrateCapsuleCalcium citrate	200 mgBelow typical rangeTypical: 300–1,000 mg/day	£0.16per day£9.64 per packBuy Nowon Amazon	Testing evidence Evidence status No public evidence located Manufacturer statement Not recorded Laboratory Not recorded Certification body Not recorded Batch Not recorded Batch-specific report Not established in this record Report date Not recorded Evidence checked 2026-09-27 09:52:54	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 20/25 Value 11/20 Dose transparency 10/15 Manufacturer transparency 9/10 Label/ingredient transparency 10/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.

Calcium form: CarbonateTabletCalcium carbonate
Daily dose: 400 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 1 tablet
Servings/day: 1
Pack size: 180 tablets

Full ingredients and formulation →

£0.05per day£8.99 per pack

View Analysis Buy Now on Amazon

Calcium form: CarbonateTabletCalcium carbonate
Daily dose: 800 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 2 tablets
Servings/day: 1
Pack size: 180 tablets

Full ingredients and formulation →

£0.11per day£9.99 per pack

View Analysis Buy Now on Amazon

Calcium form: Carbonate Calcium + DTabletCalcium carbonate
Daily dose: 800 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 2 tablets
Servings/day: 1
Pack size: 90 tablets

Full ingredients and formulation →

£0.12per day£5.49 per pack

View Analysis Buy Now on Amazon

Calcium form: Carbonate Calcium + DTabletCalcium carbonate
Daily dose: 500–1,000 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 2 tablets
Servings/day: Not disclosed
Pack size: 180 tablets

Full ingredients and formulation →

£0.06per day£11.29 per pack

View Analysis Buy Now on Amazon

Calcium form: Carbonate Calcium + DChewableCalcium carbonate
Daily dose: 800 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Chewable
Serving: 2 tablets
Servings/day: 1
Pack size: 120 chewables

Full ingredients and formulation →

£0.13per day£7.99 per pack

View Analysis Buy Now on Amazon

Calcium form: Carbonate Calcium + DTabletCalcium carbonate
Daily dose: 800 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 2 tablets
Servings/day: 1
Pack size: 100 tablets

Full ingredients and formulation →

£0.14per day£6.83 per pack

View Analysis Buy Now on Amazon

Calcium form: Carbonate Calcium + DTabletCalcium carbonate (2,222 mg)
Daily dose: 800 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 3 tablets
Servings/day: 1
Pack size: 120 tablets

Full ingredients and formulation →

£0.15per day£5.99 per pack

View Analysis Buy Now on Amazon

Calcium form: Carbonate Calcium + DCapsuleCalcium carbonate
Daily dose: 500–1,000 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Capsule
Serving: 1 capsule
Servings/day: Not disclosed
Pack size: 60 capsules

Full ingredients and formulation →

£0.06per day£3.79 per pack

View Analysis Buy Now on Amazon

Calcium form: CarbonateTabletCalcium carbonate preparation
Daily dose: 400 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 1 tablet
Servings/day: 1
Pack size: 120 tablets

Full ingredients and formulation →

£0.07per day£8.99 per pack

View Analysis Buy Now on Amazon

Calcium form: CarbonateTabletCalcium carbonate (2,028.9 mg)
Daily dose: 800 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 2 tablets
Servings/day: 1
Pack size: 180 tablets

Full ingredients and formulation →

£0.16per day£13.97 per pack

View Analysis Buy Now on Amazon

Calcium form: Carbonate Calcium + DTabletCalcium carbonate (2,500 mg)
Daily dose: 1,000 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 2 tablets
Servings/day: 1
Pack size: 120 tablets

Full ingredients and formulation →

£0.17per day£9.97 per pack

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Calcium form: Citrate Calcium + DCapsuleCalcium citrate (1,450 mg)
Daily dose: 306 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Capsule
Serving: 2 capsules
Servings/day: 1
Pack size: 120 capsules

Full ingredients and formulation →

£0.20per day£12.29 per pack

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Calcium form: CitrateCapsuleCalcium citrate (1,200 mg)
Daily dose: 300 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Capsule
Serving: 2 capsules
Servings/day: 1
Pack size: 60 capsules

Full ingredients and formulation →

£0.33per day£9.99 per pack

View Analysis Buy Now on Amazon

Calcium form: CitrateCapsuleCalcium citrate
Daily dose: 450 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Capsule
Serving: 3 capsules
Servings/day: 1
Pack size: 180 capsules

Full ingredients and formulation →

£0.60per day£35.75 per pack

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Calcium form: Mixed formsTabletCarbonate, citrate and pyruvate
Daily dose: 800 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 2 tablets
Servings/day: 1
Pack size: 120 tablets

Full ingredients and formulation →

£0.15per day£8.89 per pack

View Analysis Buy Now on Amazon

Calcium form: Mixed formsCalcium + DCapsuleCalcium citrate and calcium carbonate
Daily dose: 1,000 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Capsule
Serving: 4 capsules
Servings/day: 1
Pack size: 90 capsules

Full ingredients and formulation →

£0.68per day£14.99 per pack

View Analysis Buy Now on Amazon

Calcium form: Other calcium saltCapsuleIcelandic seaweed (Lithothamnion)
Daily dose: 260–780 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Capsule
Serving: 1 capsule
Servings/day: Not disclosed
Pack size: 60 capsules

Full ingredients and formulation →

£0.20per day£11.95 per pack

View Analysis Buy Now on Amazon

Calcium form: Other calcium saltCapsuleMicrocrystalline hydroxyapatite (MCHC), bovine
Daily dose: 750 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Capsule
Serving: 3 capsules
Servings/day: 1
Pack size: 180 capsules

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£1.23per day£73.85 per pack

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Calcium form: Mixed formsCalcium + DTabletCarbonate and citrate
Daily dose: 800 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 2 tablets
Servings/day: 1
Pack size: 90 tablets

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£0.17per day£7.50 per pack

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Calcium form: Mixed formsTabletCarbonate, citrate and gluconate
Daily dose: 1,000 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 3 tablets
Servings/day: 1
Pack size: 100 tablets

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£0.28per day£9.12 per pack

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Calcium form: Citrate Calcium + DTabletCalcium citrate
Daily dose: 1,000 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 4 tablets
Servings/day: 1
Pack size: 240 tablets

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£0.33per day£19.99 per pack

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Calcium form: CitrateCapsuleCalcium citrate (1,200 mg)
Daily dose: 300 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Capsule
Serving: 2 capsules
Servings/day: 1
Pack size: 60 capsules

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£0.37per day£10.99 per pack

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Calcium form: CitrateCapsuleCalcium citrate
Daily dose: 500 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Capsule
Serving: 3 capsules
Servings/day: 1
Pack size: 90 capsules

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£0.68per day£20.29 per pack

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Calcium form: Not disclosedCalcium + DTablet
Daily dose: 500–1,000 mgWithin typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Tablet
Serving: 1 tablet
Servings/day: Not disclosed
Pack size: 30 tablets

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£0.12per day£3.49 per pack

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Calcium form: CitrateCapsuleCalcium citrate
Daily dose: 200 mgBelow typical rangeTypical: 300–1,000 mg/day

Formulation & serving details

Format: Capsule
Serving: 2 capsules
Servings/day: 1
Pack size: 120 capsules

Full ingredients and formulation →

£0.16per day£9.64 per pack

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One-time purchase prices; delivery and conditional discounts excluded. Daily cost uses the recorded label serving. Comparison amounts are not personal dose recommendations. Unknown Prime eligibility is not treated as confirmed.

Calcium forms and labels explained

Calcium salts differ in elemental-calcium density and how dependent their absorption is on stomach acid. Compare the label-declared elemental calcium first, then use the form to understand practical differences rather than treating the compound name as a quality score.

Calcium carbonate

Common high-density calcium salt

Elemental fraction: About 40{3683f0b818e4e7eac3a25ad8212965194ab09621a23bd0189e97e17dfedff11f} by weight
Food context: Best taken with a meal

Higher elemental density can reduce compound mass, but it does not prove better clinical outcomes.

Calcium citrate

Less stomach-acid dependent

Elemental fraction: About 21{3683f0b818e4e7eac3a25ad8212965194ab09621a23bd0189e97e17dfedff11f} by weight
Food context: Can be taken without food

Often shows higher measured absorption than carbonate, but that is not a universal outcome advantage.

Other calcium salts

Several permitted mineral sources

Examples: Citrate malate, lactate, gluconate, phosphate
Compare: Elemental calcium

A less-common chemical name does not justify a higher score without relevant evidence.

Calcium plus vitamin D

Combination formula

Calcium: Record elemental mg
Vitamin D: Record separately

Do not merge vitamin D or other minerals into the calcium dose or calcium-form score.

Calcium dose: UK RNI, label NRV and supplement context

UK adults have a calcium Reference Nutrient Intake of 700 mg/day. [1] [2] This is a total dietary requirement, not a recommendation to take a 700 mg supplement.

UK labels use an adult calcium Nutrient Reference Value of 800 mg. [3] The NRV explains label percentages and should not replace the 700 mg RNI in guidance.

The NHS says taking 1,500 mg/day or less from calcium supplements is unlikely to cause harm, while higher supplemental doses can cause stomach pain and diarrhoea. [1] The UK Expert Group on Vitamins and Minerals did not set a formal calcium TUL; its 1,500 mg/day figure was guidance for supplemental intake. [4] Compare the product's elemental calcium, but do not treat 700, 800 or 1,500 mg as a universal supplement target.

What the calcium evidence shows

Calcium is essential for bone structure and normal physiological functions, but more supplemental calcium does not automatically mean better outcomes. A 2026 systematic review of 69 randomised trials found little to no clinically important fracture or fall benefit from calcium, vitamin D or combined supplementation across predominantly community-dwelling populations. [6] That finding does not replace treatment guidance for people with osteoporosis, deficiency or another diagnosed condition.

Safety evidence also needs context. The Women's Health Initiative found more reported urinary-tract stones in women assigned 1,000 mg/day calcium carbonate plus vitamin D than placebo. [7] Cardiovascular meta-analyses have reached conflicting conclusions, so the evidence does not support a simple claim that calcium supplements either cause or prevent cardiovascular disease. [8] [9]

Calcium evidence by goal

Evidence by goal
Goal	Evidence strength	What was assessed	Typical study context	Main limitation
Meeting an adult calcium requirement	Established nutritional requirement; supplement need is individual	Total calcium intake from diet and supplements	UK adult RNI is 700 mg/day.	The RNI is not a recommendation to obtain 700 mg from a supplement.
Routine fracture prevention in community-dwelling adults	Little to no clinically important benefit overall	Calcium, vitamin D or combined supplementation	2026 review: 69 randomised trials, 153,902 participants; most were community-dwelling and not high fracture risk.	Does not address individualized treatment of osteoporosis, deficiency or institutionalized high-risk populations.
Choosing citrate rather than carbonate	Moderate practical/absorption distinction; no universal clinical winner	Calcium citrate and calcium carbonate	Citrate is less dependent on stomach acid; carbonate is meal-dependent and more elementally dense.	Absorption differences do not prove superior long-term outcomes for every product.
Understanding kidney-stone risk	Signal in a major combined-supplement trial	1,000 mg/day calcium carbonate plus vitamin D3	WHI, 36,282 postmenopausal women, mean 7 years.	Combined regimen and specific population; does not justify restricting normal dietary calcium.

Read the full evidence-by-goal detail

Meeting calcium requirements

Calcium supplements can add elemental calcium when dietary intake is insufficient, but the UK RNI refers to total intake rather than the amount that should come from a bottle. [2]

Bone and fracture prevention

Calcium is required for normal bone health, but routine supplementation has not consistently reduced fractures in generally community-dwelling adults. [6]

Choosing carbonate or citrate

Calcium citrate is less dependent on stomach acid, while carbonate is best taken with food. Carbonate also contains a higher proportion of elemental calcium by compound weight. [5] These practical differences do not prove that every citrate product produces better long-term health outcomes.

When to take calcium

Timing depends partly on the calcium form. Calcium carbonate is more dependent on stomach acid and is generally better taken with a meal; calcium citrate is less acid-dependent and can be taken without food. [5]

Calcium absorption becomes proportionally lower as a single elemental dose gets larger; NIH notes the highest fractional absorption at doses of about 500 mg or less at one time. [5] Treat this as absorption context rather than a universal daily-dose rule.

Calcium also interacts with some medicines. NHS lists calcium supplements among products that may interfere with levothyroxine. [15] Follow the medicine label, pharmacist or prescriber's instructions rather than applying one generic separation interval to every medicine.

Calcium safety, kidneys and medicine interactions

Who should be cautious?If any of the following apply to you, speak to a healthcare professional before taking Calcium - see the full detail below for why.

People with chronic kidney disease or known abnormal blood calcium
People with recurrent kidney stones or a history of calcium-containing stones
People with hyperparathyroidism or another disorder affecting calcium regulation
People taking levothyroxine or other medicines known to interact with calcium
People already taking several calcium-containing products, including antacids or combination supplements

The NHS says supplemental calcium above 1,500 mg/day can cause stomach pain and diarrhoea and describes 1,500 mg/day or less from supplements as unlikely to cause harm. [1] This is not a formal TUL or a target intake.

Kidney-stone risk needs careful wording. In the Women's Health Initiative, a combined regimen of 1,000 mg calcium carbonate plus vitamin D increased reported urinary-tract stones compared with placebo. [7] This does not mean people prone to calcium-oxalate stones should simply restrict calcium foods; NHS stone guidance warns that severe dietary calcium restriction can increase urinary oxalate and advises individual guidance on supplements. [16]

Calcium can also interact with medicines, including levothyroxine and certain other drugs. [5] [15] People with kidney disease, recurrent stones, known high blood calcium, parathyroid disorders or relevant prescription medicines should seek clinician or pharmacist advice before high-dose supplementation.

Calcium with vitamin D and other minerals

Calcium is often combined with vitamin D, magnesium or zinc. Compare each nutrient separately: the calcium figure should represent elemental calcium, while vitamin D and other minerals keep their own amount, form and safety context. A combined formula does not prove that everyone needs every included nutrient.

Current UK food-supplement guidance says supplements are intended to supplement the normal diet and should not be sold as treatments for disease. [10]

Who might consider a calcium supplement

A calcium supplement can be relevant when a person's diet does not reliably provide enough calcium, but the appropriate amount depends on total dietary intake and individual circumstances. The NHS says most adults should be able to obtain the calcium they need through diet. [1]

People using calcium because of osteoporosis, low blood calcium, kidney disease, recurrent stones or a medicine-related reason are outside a simple retail-comparison decision and should use clinical advice.

How to compare calcium testing evidence

For calcium, meaningful testing evidence should confirm the elemental calcium potency of the finished product, identify the calcium source and show what contaminants or other quality attributes were assessed. In combination products, check whether vitamin D and other declared actives were also within the report's scope.

A legal food-supplement label is not the same as independent batch verification. [10] The Supplement Compare's testing guide separates marketing claims, manufacturer COAs, independent evidence and recognised certification. Read the guide Testing can support identity and potency; it does not prove fracture prevention or personal suitability.

Blood testing & your results

A routine serum calcium result is not a direct measure of dietary calcium intake or body calcium stores. Serum calcium is tightly regulated, and NIH notes that total serum/plasma calcium is not a good reflection of nutritional calcium status. [5] Blood calcium testing is clinically useful when a clinician is investigating abnormal calcium physiology, kidney/parathyroid problems or related conditions, but this comparison page should not recommend routine screening simply to choose a supplement.

Testing evidence in this comparison

A testing claim is not the same as a verified report. No public evidence located does not mean a product has not been tested.

Testing review pending0

Recognised certification0

Verified independent evidence1

Manufacturer COA0

Testing claimed16

No public evidence located8

What does calcium cost?

Current UK comparison set, based on the daily serving shown on each label.

£0.05Lowest daily cost

£0.16Median daily cost

£1.23Highest daily cost

Your questions, answered

How much calcium do adults need in the UK?

The UK adult RNI is 700 mg/day from total intake. [1] [2] The 800 mg figure shown as an NRV on labels is a labelling reference, not a different personal requirement. [3]

Is calcium citrate better than calcium carbonate?

Not universally. Citrate is less dependent on stomach acid and can be taken without food; carbonate is more elementally dense and is better taken with a meal. [5] These differences do not prove that every citrate product gives better health outcomes.

What does elemental calcium mean?

Elemental calcium is the actual amount of calcium supplied, separate from the total weight of the calcium compound. Calcium carbonate is about 40{3683f0b818e4e7eac3a25ad8212965194ab09621a23bd0189e97e17dfedff11f} elemental calcium by weight and citrate about 21{3683f0b818e4e7eac3a25ad8212965194ab09621a23bd0189e97e17dfedff11f}, so compare the label-declared calcium amount rather than compound mass. [5]

Can calcium supplements cause kidney stones?

Some evidence raises concern. In the WHI, 1,000 mg/day calcium carbonate plus vitamin D increased reported urinary-tract stones compared with placebo. [7] The finding was for a combined regimen in postmenopausal women and should not be turned into advice to restrict normal dietary calcium.

Does a calcium blood test show whether I eat enough calcium?

Not reliably. Serum calcium is tightly regulated and is not a good reflection of nutritional calcium status. [5] A clinician may order calcium tests for medical reasons, but this page does not recommend routine testing for supplement selection.

Sources & methodology

Read our methodology and how we verify testing.

Page updated26 Sep 2026

Editorial reviewSources checked 2026-09-26; editorial preview

Product evidenceSee individual records

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Calcium forms and labels explained

Calcium carbonate

Calcium citrate

Other calcium salts

Calcium plus vitamin D

Calcium dose: UK RNI, label NRV and supplement context

What the calcium evidence shows

Calcium evidence by goal

Meeting calcium requirements

Bone and fracture prevention

Choosing carbonate or citrate

When to take calcium

Calcium safety, kidneys and medicine interactions

Calcium with vitamin D and other minerals

Who might consider a calcium supplement

How to compare calcium testing evidence

Blood testing & your results

Testing evidence in this comparison

What does calcium cost?

Your questions, answered

Sources & methodology