Compare the labelled daily biotin in mcg. The 50 mcg UK label NRV explains label percentages and is not a target supplement dose. Higher-dose products can interfere with some blood tests, so tell a clinician if you take biotin before testing. 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 ↓

Biotin product comparison
#	Product	Formulation	Daily dose	Price/day	Testing	Score
1	Natures Zest High Strength Biotin Tablets 10000mcg – TabletsNatures Zest120 tablets	D-biotinTablet	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.17per day£19.99 per packBuy Nowon Amazon	Testing evidence Evidence status Verified independent evidence Manufacturer statement Manufacturer page says "Independently Lab Tested" and links to a certificate; the certificate reads "CERTIFICATE OF ANALYSIS" for "Sample Description Natures Zest Biotin Complex" and lists microbiological results. Laboratory i2 F.A.S.T Certification body Not recorded Batch Batch No-26290 Batch-specific report Recorded Report date Not recorded Evidence checked 2026-09-27 10:14:51 Certificate of analysis ↗ Laboratory report ↗ Manufacturer testing page ↗	Why this score? Testing & evidence 19/20 Ingredient/formulation quality 21/25 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.
2	VitaBright D-Biotin 12000mcg – TabletsVitaBright400 tablets	D-biotinTablet	12,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.02per day£8.49 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement VitaBright’s own product page says: “Who performs your testing, an in-house lab or an independent third party?” and “Do you have a Certificate of Analysis (CoA) for your products or their ingredients?” The page also says the brand has a “Product Testing and Quality Controls” article, but I did not find a product-specific CoA, lab report, or certifying-body registry entry for this biotin 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 10:28:33 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 21/25 Value 19/20 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	WeightWorld Biotin 12000mcg – TabletsWeightWorld365 tablets	D-biotinTablet	12,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.03per day£9.99 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement WeightWorld product page says: "Third-party lab-tested for pesticides and heavy metals to ensure purity and potency" and also shows "10/10 TESTS PASSED / 3/3 CLAIMS VERIFIED / INDEPENDENTLY LAB-TESTED / SEE LAB RESULTS". 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 10:39:32 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 21/25 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	Red Label Health Biotin 10 mg D-biotin 10000mcg – TabletsRed Label Health400 tablets	D-biotinTablet	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.02per day£7.49 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 10:16:47	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 21/25 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.
5	NutriVolv Biotin Hair Growth Supplement 365 tablets 10000mcg – TabletsNutriVolv365 tablets	D-biotinTablet	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.02per day£6.89 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 10:13:13	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 21/25 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.
6	Simply Supplements Biotin 10,000 mcg D-biotin 10000mcg – TabletsSimply Supplements120 tablets	D-biotinTablet	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.07per day£8.99 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Simply Supplements product page says: "Our ingredients are carefully selected and tested for purity and safety – ensuring quality you can trust." 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 10:17:45 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 21/25 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.
7	Igennus Clean Biotin 10000mcg – CapsulesIgennus180 capsules	D-biotinCapsule	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.07per day£12.99 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Amazon listing and Igennus product page both say the product is "lab verified" / "PURE & CLEAN - we use hypoallergenic and lab-verified ingredients" and the Amazon bullets say "lab verified" and "GMP manufactured in the UK & lab verified to ensure the highest quality." I found no independently verifiable COA or registry entry for this specific biotin 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 10:23:25 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 21/25 Value 15/20 Dose transparency 15/15 Manufacturer transparency 7/10 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	Zipvit Biotin 12000mcg – TabletsZipvit180 tablets	Biotin in a blendTabletZinc 10 mg, selenium 55 mcg	12,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.08per day£6.99 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Amazon listing says "3rd Party Tested"; Zipvit product page says "4/4 TESTS PASSED", "1/1 CLAIMS VERIFIED", and "INDEPENDENTLY LAB-TESTED" / "SEE LAB RESULTS". 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 10:27:12 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 21/25 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.
9	Xspan Labs Biotin 10000mcg – TabletsXspan Labs120 tablets	D-biotinTablet	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.08per day£9.97 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement xSpan Labs product page says: "Every batch is tested for purity and potency." 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 10:21:10 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 21/25 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.
10	Nutrition Geeks Biotin Hair Growth Supplement 10000mcg – TabletsNutrition Geeks365 tablets	D-biotinTablet	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.02per day£8.99 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 10:33:45	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 21/25 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.
11	Evo Nutrition Biotin Max 12000mcg – TabletsEvo Nutrition400 tablets	Biotin in a blendTabletZinc and selenium	12,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.03per day£9.99 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 10:37:44	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 21/25 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.
12	Nutricost Biotin 10000mcg – CapsulesNutricost240 capsules	Not disclosedCapsule	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.06per day£14.95 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Nutricost product page says: “Nutricost Biotin is Non-GMO, Gluten Free, and 3rd Party Tested” and “Nutricost products are tested by an independent, accredited lab to help verify that what’s on the label is what’s in the bottle.” 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 10:18:24 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 18/25 Value 15/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 9/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
13	Nu U Nutrition Biotin 10,000 mcg micro tablets 10000mcg – TabletsNu U Nutrition365 tablets	D-biotinTablet	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.04per day£14.97 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 10:25:01	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 21/25 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.
14	Right Choice Supplements Biotin Grow 10000mcg – TabletsRight Choice Supplements180 tablets	Biotin in a blendTabletZinc 10 mg, copper 1 mg	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.04per day£3.99 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 10:35:11	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 21/25 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.
15	New Leaf Products New Leaf Biotin+ 12000mcg – TabletsNew Leaf Products180 tablets	Biotin in a blendTabletZinc 5 mg, selenium 60 mcg	12,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.10per day£8.94 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 to fully comply with global regulations." 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 10:38:37 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 21/25 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.
16	Pinnacle Nutrition Biotin 12,000 mcg tablets 12000mcg – TabletsPinnacle Nutrition400 tablets	Not disclosedTablet	12,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.02per day£8.79 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 10:24:09	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 18/25 Value 19/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 9/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
17	Swiss BioEnergetics Biotin 10,000 mcg D-biotin 10000mcg – Tabletsswiss bioenergetics120 tablets	D-biotinTablet	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.07per day£8.97 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 10:22:25	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 21/25 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.
18	Right Choice Supplements Biotin 10,000 mcg tablets 10000mcg – TabletsRight Choice Supplements180 tablets	Not disclosedTablet	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.02per day£3.99 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 10:26:39	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 18/25 Value 18/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 9/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
19	Nutrition Geeks Biotin Growth+ 10000mcg – TabletsNutrition Geeks180 tablets	Biotin in a blendTabletZinc 10 mg, selenium 55 mcg	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.08per day£6.99 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 10:41:52	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 21/25 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	Nutravita Biotin + Zinc & Selenium 10000mcg – TabletsNutravita180 tablets	Biotin in a blendTabletZinc 20 mg, selenium 55 mcg	10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.09per day£7.99 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 10:14:04	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 21/25 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	Pure Encapsulations Biotin 8 mg 8000mcg – CapsulesPure Encapsulations60 capsules	Not disclosedCapsule	8,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day	£0.27per day£16.00 per packBuy Nowon Amazon	Testing evidence Evidence status No public evidence located Manufacturer statement Pure Encapsulations’ Biotin 8 mg product sheet states: “Certified Gluten-Free by the Gluten-Free Certification Organization, gluten.org.” 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 10:31:18 Manufacturer testing page ↗	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 18/25 Value 9/20 Dose transparency 15/15 Manufacturer transparency 9/10 Label/ingredient transparency 9/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
22	Swansons Swanson Biotin 5,000 mcg 5000mcg – CapsulesSwansons100 capsules	Not disclosedCapsule	5,000 mcgBelow typical rangeTypical: 7,000–13,000 mcg/day	£0.10per day£9.99 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 10:15:41	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 17/25 Value 9/20 Dose transparency 10/15 Manufacturer transparency 7/10 Label/ingredient transparency 9/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
23	Solgar Biotin 5000 mcg 5000mcg – CapsulesSolgar50 capsules	Not disclosedCapsule	5,000 mcgBelow typical rangeTypical: 7,000–13,000 mcg/day	£0.34per day£16.99 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 10:36:09	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 17/25 Value 7/20 Dose transparency 10/15 Manufacturer transparency 9/10 Label/ingredient transparency 9/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
24	Healthspan Biotin 1,000 mcg 1000mcg – TabletsHealthspan180 tablets	Not disclosedTablet	1,000 mcgBelow typical rangeTypical: 7,000–13,000 mcg/day	£0.08per day£14.99 per packBuy Nowon Amazon	Testing evidence Evidence status Testing claimed Manufacturer statement Healthspan’s own site says the product is a “high strength vegan formulation” and that it contains “1000 µg biotin”; Healthspan Elite also says “Informed Sport assures athletes that products bearing its logo are regularly tested for banned substances,” but I did not find an independent registry page confirming this specific biotin product is certified. 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 10:19:18 Manufacturer testing page ↗	Why this score? Testing & evidence 9/20 Ingredient/formulation quality 13/25 Value 5/20 Dose transparency 6/15 Manufacturer transparency 7/10 Label/ingredient transparency 9/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.
25	Solgar Biotin 1000 mcg 1000mcg – CapsulesSolgar50 capsules	Not disclosedCapsule	1,000 mcgBelow typical rangeTypical: 7,000–13,000 mcg/day	£0.14per day£7.13 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 10:32:41	Why this score? Testing & evidence 4/20 Ingredient/formulation quality 13/25 Value 5/20 Dose transparency 6/15 Manufacturer transparency 9/10 Label/ingredient transparency 9/10 Displayed points and weights are rounded; the total uses unrounded weights. Pending dimensions are excluded. Provisional scores may change after review.

Formulation: D-biotinTablet
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

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

Full ingredients and formulation →

£0.17per day£19.99 per pack

View Analysis Buy Now on Amazon

Formulation: D-biotinTablet
Daily dose: 12,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

Format: Tablet
Serving: 1 tablet
Servings/day: 1
Pack size: 400 tablets

Full ingredients and formulation →

£0.02per day£8.49 per pack

View Analysis Buy Now on Amazon

Formulation: D-biotinTablet
Daily dose: 12,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

Format: Tablet
Serving: 1 tablet
Servings/day: 1
Pack size: 365 tablets

Full ingredients and formulation →

£0.03per day£9.99 per pack

View Analysis Buy Now on Amazon

Formulation: D-biotinTablet
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

Format: Tablet
Serving: 1 tablet
Servings/day: 1
Pack size: 400 tablets

Full ingredients and formulation →

£0.02per day£7.49 per pack

View Analysis Buy Now on Amazon

Formulation: D-biotinTablet
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

Format: Tablet
Serving: 1 tablet
Servings/day: 1
Pack size: 365 tablets

Full ingredients and formulation →

£0.02per day£6.89 per pack

View Analysis Buy Now on Amazon

Formulation: D-biotinTablet
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/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

Formulation: D-biotinCapsule
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

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

Full ingredients and formulation →

£0.07per day£12.99 per pack

View Analysis Buy Now on Amazon

Formulation: Biotin in a blendTabletZinc 10 mg, selenium 55 mcg
Daily dose: 12,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

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

Full ingredients and formulation →

£0.08per day£6.99 per pack

View Analysis Buy Now on Amazon

Formulation: D-biotinTablet
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

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

Full ingredients and formulation →

£0.08per day£9.97 per pack

View Analysis Buy Now on Amazon

Formulation: D-biotinTablet
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

Format: Tablet
Serving: 1 tablet
Servings/day: 1
Pack size: 365 tablets

Full ingredients and formulation →

£0.02per day£8.99 per pack

View Analysis Buy Now on Amazon

Formulation: Biotin in a blendTabletZinc and selenium
Daily dose: 12,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

Format: Tablet
Serving: 1 tablet
Servings/day: 1
Pack size: 400 tablets

Full ingredients and formulation →

£0.03per day£9.99 per pack

View Analysis Buy Now on Amazon

Formulation: Not disclosedCapsule
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

Format: Capsule
Serving: 1 capsule
Servings/day: 1
Pack size: 240 capsules

Full ingredients and formulation →

£0.06per day£14.95 per pack

View Analysis Buy Now on Amazon

Formulation: D-biotinTablet
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

Format: Tablet
Serving: 1 tablet
Servings/day: 1
Pack size: 365 tablets

Full ingredients and formulation →

£0.04per day£14.97 per pack

View Analysis Buy Now on Amazon

Formulation: Biotin in a blendTabletZinc 10 mg, copper 1 mg
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

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

Full ingredients and formulation →

£0.04per day£3.99 per pack

View Analysis Buy Now on Amazon

Formulation: Biotin in a blendTabletZinc 5 mg, selenium 60 mcg
Daily dose: 12,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

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

Full ingredients and formulation →

£0.10per day£8.94 per pack

View Analysis Buy Now on Amazon

Formulation: Not disclosedTablet
Daily dose: 12,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

Format: Tablet
Serving: 1 tablet
Servings/day: 1
Pack size: 400 tablets

Full ingredients and formulation →

£0.02per day£8.79 per pack

View Analysis Buy Now on Amazon

Formulation: D-biotinTablet
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

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

Full ingredients and formulation →

£0.07per day£8.97 per pack

View Analysis Buy Now on Amazon

Formulation: Not disclosedTablet
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

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

Full ingredients and formulation →

£0.02per day£3.99 per pack

View Analysis Buy Now on Amazon

Formulation: Biotin in a blendTabletZinc 10 mg, selenium 55 mcg
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

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

Full ingredients and formulation →

£0.08per day£6.99 per pack

View Analysis Buy Now on Amazon

Formulation: Biotin in a blendTabletZinc 20 mg, selenium 55 mcg
Daily dose: 10,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

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

Full ingredients and formulation →

£0.09per day£7.99 per pack

View Analysis Buy Now on Amazon

Formulation: Not disclosedCapsule
Daily dose: 8,000 mcgWithin typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

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

Full ingredients and formulation →

£0.27per day£16.00 per pack

View Analysis Buy Now on Amazon

Formulation: Not disclosedCapsule
Daily dose: 5,000 mcgBelow typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

Format: Capsule
Serving: 1 capsule
Servings/day: 1
Pack size: 100 capsules

Full ingredients and formulation →

£0.10per day£9.99 per pack

View Analysis Buy Now on Amazon

Formulation: Not disclosedCapsule
Daily dose: 5,000 mcgBelow typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

Format: Capsule
Serving: 1 vegetable capsule
Servings/day: 1
Pack size: 50 capsules

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£0.34per day£16.99 per pack

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Formulation: Not disclosedTablet
Daily dose: 1,000 mcgBelow typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

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

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£0.08per day£14.99 per pack

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Formulation: Not disclosedCapsule
Daily dose: 1,000 mcgBelow typical rangeTypical: 7,000–13,000 mcg/day

Formulation & serving details

Format: Capsule
Serving: 1 vegetable capsule
Servings/day: 1
Pack size: 50 capsules

Full ingredients and formulation →

£0.14per day£7.13 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.

Biotin forms and labels explained

Biotin products differ more by dose, blend composition and physical format than by a proven hierarchy of chemical forms. Keep the label amount in micrograms and separate biotin from other actives.

D-biotin

Biotin ingredient identity

GB-listed form: D-biotin
Dose unit: mcg

The GB register lists D-biotin. Disclosure of the full name does not by itself prove superior absorption or results.

Biotin in a blend

Multi-ingredient formula

Compare: Biotin separately
Also record: Other actives

Zinc, selenium and other ingredients need their own amounts and evidence; do not attribute the blend's claims to biotin alone.

High-dose biotin

Dose context, not a new form

1 mg: 1,000 mcg
Key issue: Lab-test interference

A larger number is not automatically better. High-dose products need explicit blood-test interference context.

Biotin dose: UK label references and high-dose context

The UK adult biotin Nutrient Reference Value used on labels is 50 mcg. [2] This figure is useful for understanding label percentages, but it is not a personal supplement prescription.

The NHS does not set a numeric adult daily requirement on its biotin guidance. It says people should be able to get the biotin they need from a varied, balanced diet and that taking 0.9 mg (900 mcg) or less per day from supplements is unlikely to cause harm. [1] That 900 mcg statement is safety context, not an intake target and not a formal upper limit.

For comparison, keep all products in micrograms: 1 mg equals 1,000 mcg. A 5 mg label therefore provides 5,000 mcg. Do not treat a larger number as evidence of better results.

What the evidence says about biotin

Biotin deficiency can affect hair, skin and nails, but this does not mean extra biotin improves them in people who are not deficient. A 2024 review found only three eligible studies of oral biotin for hair growth; the highest-quality placebo-controlled study found no difference between biotin and placebo, and the remaining studies involved selected clinical populations. [5]

Evidence for brittle nails is also limited. An older uncontrolled report used 2.5 mg (2,500 mcg) per day and reported improvement among many evaluable participants, but the lack of a placebo group, attrition and age of the study limit what can be concluded for typical shoppers. [8]

Biotin evidence by goal

Evidence by goal
Goal	Evidence strength	What was assessed	Typical study context	Main limitation
Hair growth in adults without known deficiency	Weak / insufficient	Oral biotin across three eligible studies in a 2024 review	The highest-quality placebo-controlled study found no difference; the other studies used selected clinical populations.	Very small and heterogeneous evidence base; deficiency findings do not establish benefit in replete adults.
Brittle nails	Limited, low-certainty	Oral biotin 2.5 mg/day	Older clinical report; 71 treated and 45 evaluable, with mean treatment around 5.5 months.	No placebo control, attrition and old evidence; not proof for healthy nails.
Avoiding misleading blood-test results	Well-established analytical risk	High-dose oral biotin and biotin-sensitive immunoassays	Human and laboratory guidance show dose-, test- and platform-dependent interference.	Not every assay is affected and there is no single universal washout interval.

Read the full evidence-by-goal detail

Hair growth

Evidence for routine biotin supplementation in people without a demonstrated deficiency is weak. Deficiency can cause hair changes, but deficiency evidence should not be turned into a general hair-growth claim. [5] [6]

Nails

Small, older uncontrolled studies suggest possible benefit in brittle-nail populations, but they do not establish that high-dose biotin strengthens normal nails in everyone. [8]

Correcting deficiency

True biotin deficiency is uncommon, and suspected deficiency is a clinical question rather than a reason to rank ordinary retail products by the highest dose. [6]

When to take biotin

No source reviewed established a universal morning-versus-evening advantage for ordinary biotin supplements. Follow the product's labelled directions unless a healthcare professional gives different instructions. The more important timing issue is laboratory testing: biotin can interfere with some immunoassays, so tell the clinician or laboratory what you take before a test and follow their test-specific instructions. [3] [7]

Biotin safety and blood-test interference

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

People having thyroid, cardiac, hormone or other immunoassay-based laboratory tests
People taking very high-dose biotin products
People being investigated or treated for a medical condition where laboratory results affect decisions
Pregnant or breastfeeding people should use clinician-led advice rather than extrapolating from general retail products

The NHS says there is not enough evidence to know the effects of high daily doses of biotin supplements and describes 0.9 mg (900 mcg) or less per day from supplements as unlikely to cause harm. [1] European upper-level tables state that there are not adequate data to derive a biotin UL. [4] The absence of a formal UL is not evidence that unlimited intake is safe.

A separate risk is laboratory-test interference. The MHRA warns that biotin can interfere with thyroid immunoassays and may produce falsely high or falsely low results, with greater risk at higher doses. [3] Laboratory guidance shows that susceptibility varies by assay and manufacturer, so this page should not give one universal 'stop biotin for X hours' rule. [7]

Biotin in hair, skin and nail blends

Many hair, skin and nail products combine biotin with zinc, selenium, vitamins or other ingredients. Compare each active separately. A blend does not make the biotin dose more effective, and benefits supported for another ingredient should not be attributed to biotin. UK food-supplement guidance also distinguishes food supplements from medicines and does not permit them to be sold as disease treatments. [10]

Who might consider biotin

The clearest role for biotin supplementation is where intake or deficiency is a genuine concern assessed in context. Deficiency itself is uncommon in healthy people eating a mixed diet. [6] People shopping mainly for hair or nail benefits should know that evidence in non-deficient adults is limited. Anyone having blood tests should disclose biotin use because it can distort some results. [3]

How to compare biotin testing evidence

For biotin, useful product evidence confirms that the finished product contains the declared ingredient and amount and identifies what contaminants or other quality attributes were checked. A generic 'third-party tested' statement is weaker than a traceable report or certification record tied to the exact product. The Supplement Compare's testing guide explains these evidence levels. Read the guide

Do not treat a GMP statement as batch-specific potency evidence, and do not treat a testing badge as proof that biotin will improve hair, skin or nails.

Blood testing & your results

Biotin is unusually relevant to blood testing because it can interfere with some streptavidin-biotin immunoassays. In the UK, the MHRA specifically warns about thyroid-function tests and advises healthcare professionals to ask about biotin intake. [3] Interference depends on the dose, assay design, platform and timing. Laboratory guidance therefore supports test-specific advice rather than one universal washout interval. [7] Tell the clinician or laboratory about all biotin-containing supplements before testing.

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 claimed9

No public evidence located15

What does biotin cost?

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

£0.02Lowest daily cost

£0.07Median daily cost

£0.34Highest daily cost

Your questions, answered

How much biotin do I need in the UK?

The NHS does not give a numeric adult daily requirement for biotin and says a varied, balanced diet should provide what is needed. [1] The 50 mcg figure on UK labels is the Nutrient Reference Value used for labelling, not a personal supplement prescription. [2]

Is 10,000 mcg of biotin the same as 10 mg?

Yes. 1 mg equals 1,000 mcg, so 10 mg equals 10,000 mcg. The conversion is arithmetic; it does not imply that 10 mg is an appropriate dose.

Does biotin make hair grow faster?

Evidence in people without biotin deficiency is weak. A 2024 review found only three eligible oral-biotin hair studies and concluded that high-quality evidence does not support routine biotin as a hair supplement. [5]

Can biotin affect thyroid blood tests?

Yes. The MHRA warns that biotin can interfere with thyroid immunoassays and can produce falsely high or falsely low results. [3] Tell the clinician or laboratory what you take before testing rather than relying on a universal stop-taking interval.

Is there a safe upper limit for biotin?

No formal tolerable upper intake level has been established from the reviewed European evidence because adequate data were not available. [4] That does not mean unlimited doses are proven safe.

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

Biotin Supplements

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Biotin forms and labels explained

D-biotin

Biotin in a blend

High-dose biotin

Biotin dose: UK label references and high-dose context

What the evidence says about biotin

Biotin evidence by goal

Hair growth

Nails

Correcting deficiency

When to take biotin

Biotin safety and blood-test interference

Biotin in hair, skin and nail blends

Who might consider biotin

How to compare biotin testing evidence

Blood testing & your results

Testing evidence in this comparison

What does biotin cost?

Your questions, answered

Sources & methodology