Best Vitamin D Supplements, Scored on a Public Rubric
Vitamin D3 (cholecalciferol) is the form to choose — D3 is what your skin produces, and head-to-head trials show it raises serum 25(OH)D more efficiently than D2 (ergocalciferol). Per Straits Research, D3 accounts for 92.65% of US vitamin D revenue. Where products differ is in dose accuracy, whether they pair vitamin K2 (which directs calcium to bone vs soft tissue), and how well-tested they are. We scored six.
Top pick
Thorne — Vitamin D3 + K2
1,000 IU D3 + 200mcg K2 (MK-4), NSF Certified for Sport softgel
Sports Research — Sports Research Vitamin D3 with Coconut Oil
At a glance
Tap a column to sort| # | Best for | Price | ||
|---|---|---|---|---|
| 1 | | Best overall D3 | 8.5/10 | $34.00 |
| 2 | | Best value per IU | 8.5/10 | $18.95 |
| 3 |  | Best USP-verified mainstream option | 8.3/10 | $9.99$19.29 |
| 4 |  | Alternative delivery for people who dislike swallowing softgels | 7.7/10 | $15.61$17.40 |
| 5 |  | Best gummy option for kids/adults who won't swallow softgels | 7.7/10 | $18.66 |
| 6 |  | Budget softgel with D3 only | 8.3/10 | $14.75 |
Prices pulled from Amazon as of Jul 6, 2026 and are subject to change. The price shown on Amazon at checkout applies.
How we scored
Every product below is scored on six metrics, 0-10 each, with the weighting described on how we review. The criteria specific to this category:
- Vitamin D3 (cholecalciferol), not D2.
- Dose accuracy — ConsumerLab and independent testing have repeatedly found vitamin D supplements both under- and over-dosed.
- Optional K2 pairing (MK-7 form is most bioavailable) for calcium distribution.
- Delivery form — softgel with fat is more reliably absorbed than dry tablet.
- Third-party testing evidence.
- Price per effective IU.
What to know before buying
- Typical supplemental dosing is 1,000-4,000 IU (25-100mcg) per day for adults. Higher doses (5,000+) should follow a serum 25(OH)D test, not guesswork.
- Vitamin D is fat-soluble — take with a meal containing fat for best absorption.
- K2 pairing matters most at higher D doses (≥2,000 IU), where calcium distribution to bone becomes more important.
Our picks
Thorne — Vitamin D3 + K2
Key specs: 1,000 IU D3 + 200mcg K2 (MK-4), NSF Certified for Sport softgel
$34.00Check price on AmazonPros
- NSF Certified for Sport
- Combines D3 with K2 (though MK-4, which has a shorter half-life than MK-7)
- Medium dose — easy to titrate
Cons
- MK-4 requires more frequent dosing than MK-7
- Premium cost per IU
Thorne — Vitamin D3 + K2
- Third-party testing10/10
- Bioavailability9/10
- Clinical evidence8/10
- Value6/10
- Brand transparency9/10
- Form & absorption9/10
Sports Research — Sports Research Vitamin D3 with Coconut Oil
Key specs: 5,000 IU D3 in organic coconut oil softgel, 360-count
$18.95Check price on AmazonPros
- Coconut oil base aids absorption of fat-soluble vitamin
- Large count at very reasonable price per IU
- Non-GMO and Informed Choice listed batches
Cons
- 5,000 IU is higher than general daily need without a tested deficiency
- No K2 included — pair separately if desired
Sports Research — Sports Research Vitamin D3 with Coconut Oil
- Third-party testing7/10
- Bioavailability9/10
- Clinical evidence8/10
- Value10/10
- Brand transparency8/10
- Form & absorption9/10
Nature Made — Nature Made Vitamin D3 1000 IU
Key specs: 1,000 IU D3 softgel, USP Verified
$9.99$19.2948% offCheck price on AmazonPros
- USP Verified — among the most rigorous US third-party quality marks
- Widely available, consistent quality
- Low cost per IU
Cons
- No K2
- Packaging is basic
Nature Made — Nature Made Vitamin D3 1000 IU
- Third-party testing9/10
- Bioavailability8/10
- Clinical evidence8/10
- Value9/10
- Brand transparency8/10
- Form & absorption8/10
NOW Foods — NOW D3 + K2 Liposomal Spray
Key specs: 1,000 IU D3 + 100mcg K2 per spray, liposomal spray format
$15.61$17.4010% offCheck price on AmazonPros
- Spray format — travel and swallow-friendly
- NOW publishes batch COAs
- Includes K2 (MK-7)
Cons
- Cost per IU higher than softgel format
- Taste is polarizing
NOW Foods — NOW D3 + K2 Liposomal Spray
- Third-party testing8/10
- Bioavailability8/10
- Clinical evidence7/10
- Value7/10
- Brand transparency8/10
- Form & absorption8/10
Nordic Naturals — Nordic Naturals Vitamin D3 Gummies
Key specs: 1,000 IU D3 per gummy, non-GMO, 3rd-party tested
$18.66Check price on AmazonPros
- Nordic Naturals' third-party testing standards
- Gummy format is appealing for those resistant to capsules
Cons
- Gummies typically include added sugar (2-3g per gummy)
- Gummies degrade faster in heat than softgels
Nordic Naturals — Nordic Naturals Vitamin D3 Gummies
- Third-party testing9/10
- Bioavailability7/10
- Clinical evidence8/10
- Value6/10
- Brand transparency9/10
- Form & absorption7/10
Life Extension — Life Extension Vitamin D3 with Sea-Iodine
Key specs: 5,000 IU D3 per softgel, 60-count
$14.75Check price on AmazonPros
- High-dose D3 with transparent COA publishing
- Affordable per IU
Cons
- No K2
- 5,000 IU should follow a blood test, not be the default choice
Life Extension — Life Extension Vitamin D3 with Sea-Iodine
- Third-party testing8/10
- Bioavailability8/10
- Clinical evidence8/10
- Value9/10
- Brand transparency9/10
- Form & absorption8/10
Frequently asked questions
The RDA for adults is 600 IU (15mcg) per day, rising to 800 IU (20mcg) for adults over 70. The tolerable upper intake level for healthy adults is 4,000 IU. Dosing beyond the RDA should ideally be informed by a serum 25(OH)D test.
Sources
- Vitamin D — Fact Sheet for Health Professionals — NIH Office of Dietary Supplements
- Comparison of vitamin D2 and vitamin D3 supplementation — The American Journal of Clinical Nutrition, 2012
- Vitamin K and calcification — Integrative Medicine Encyclopedia, 2015
- USP Verified Dietary Supplements
Last verified: April 21, 2026. See our editorial policy and how we review for details on scoring and update cadence. Canonical URL: https://trustedhealthgear.com/reviews/best-vitamin-d.
Thorne — Vitamin D3 + K2
$34.00 · on Amazon