Learn
Know what you’re paying for
Short guides on labels, units and prices – every number worked out from the products we checked. No health claims, no rankings for sale.
13
guides
256
supplements explained
17,287
products behind the numbers
Start here · Label basicsHow to read a Supplement Facts labelServing size, % Daily Value, “proprietary blend” – what the box on the back of the bottle means, and which number you need to compare prices.Read the guide · 5 minLabel basics
Read the label
What the numbers in the Supplement Facts box mean – and which one you need to compare prices.
Label basicsmg, mcg, IU, DFE, CFU: the units on a supplement label
Why vitamin D comes in mcg and IU, what “DFE” means for folate and how to read “billion CFU” – with the conversions from the NIH.5 min read
Label basicsProprietary blends: when the label hides the amounts
A blend only has to show its total weight. Which supplements use blends most – and why they make the price per dose impossible to check.4 min read
Saving money
Pay less per dose
Pack sizes and formats – the two things that change the price of the same dose the most.
Saving moneyBigger packs: how much you really save per dose
We compared every product we found in more than one size. How much the big pack saves – and when it costs more than the small one.4 min read
Saving moneyPowder, capsules or gummies: what convenience costs
The same amount of the same ingredient – but a very different price per dose. What we found across all the supplements we checked.4 min read
Quality
Quality and testing
What a higher price, a testing seal and our quality score do – and don’t – tell you.
QualityDoes a higher price buy a better supplement?
We put our quality score next to the price of every product we checked. What paying more does – and doesn’t – get you.4 min read
QualityNSF, USP, Informed Sport: what testing seals check
The FDA doesn’t check supplements before they’re sold. What independent seals check, how to look a product up – and what a seal costs extra.5 min read
By supplement
Supplement by supplement
The six we get asked about most – with the numbers from every product we checked.
Protein powderProtein powder: the cheaper tub isn’t always the cheaper protein
Scoops hold very different amounts of protein. What that does to the price – with numbers from the powders we checked.4 min read
CreatineCreatine: powder, capsules or gummies – what 5 g costs
The same creatine monohydrate, but a very different price per 5 g. And why capsules add up.4 min read
Omega-3Fish oil, krill oil or algae oil: what 1,000 mg of EPA + DHA costs
“1,000 mg fish oil” isn’t 1,000 mg of omega-3. How to read the label – and how much more krill and algae oil cost.4 min read
MagnesiumMagnesium glycinate, citrate, oxide: how much magnesium is really in it
“1,000 mg magnesium glycinate” is only about 140 mg of magnesium. Why the form matters for the label and the price.4 min read
Vitamin DVitamin D: IU, mcg and what you really pay
How to convert IU to mcg, what the official upper limit is, and why the cheapest price per dose can be misleading.4 min read
ElectrolytesElectrolytes: what you pay for 500 mg of sodium
Some sticks have very little sodium, others many times more. That’s why the price per stick says very little.3 min read
Look it up
Every supplement, and how we work
Supplements A–Z
All 256 supplements in plain words – what each one is and the amount we compare prices by.
All 256 supplementsHow we check
Every number on this site comes from a store or a label you can look up yourself.
- Prices from US online stores, always with the date we checked
- Amounts from the label or the NIH label database – never estimated
- Sorted by numbers only – no brand can pay for a better place