The %DV on a label tells you how much a serving gives against a set reference amount. Pick a nutrient below, enter the amount in your supplement, and this tool returns the percentage of the FDA Daily Value. It uses the current Daily Values for adults and children aged 4 and over.

How this works

The percent Daily Value is a simple ratio:

%DV = amount in the serving ÷ Daily Value × 100

For example, a supplement with 500 mg of vitamin C, against a Daily Value of 90 mg, gives 500 ÷ 90 × 100, which is about 556% of the Daily Value. The Daily Values used here are the current FDA reference amounts for adults and children aged 4 and over.

Understanding your result

A %DV of 100 means the serving provides the full reference amount for that nutrient. Many supplements list several hundred percent, which is common and often fine for water-soluble vitamins, but worth watching for nutrients that have an upper limit, such as some minerals and fat-soluble vitamins. The Daily Value is a single reference number, not a personal target, so your own needs may be higher or lower depending on age, sex, and health.

Important limitations

• The Daily Value is one fixed reference number. It is not the same as your personal recommended intake, which varies by age and sex.
• Make sure your amount is in the same unit shown for the nutrient, since mixing mg and mcg gives a wrong result.
• A high %DV is not automatically better, and for some nutrients it can approach an upper limit.
• This does not account for the nutrient you also get from food.

Scientific basis

The Daily Values used here are the official FDA reference amounts for nutrition and supplement labels:

• Daily Values for adults and children 4 and over (US FDA)
• Daily Values explained, NIH Office of Dietary Supplements

This calculator is for general education only and is not medical or professional advice. Always check product labels and speak with a qualified professional before making decisions about supplements.