What this tool shows
This tool reads the recommended daily intake straight from each country's or region's official nutrition authority: the US/Canada Dietary Reference Intakes (DRI), Korea's Dietary Reference Intakes for Koreans (KDRIs, 2025), Japan's Dietary Reference Intakes (DRIs, 2025), and the EU's Dietary Reference Values (EFSA, 2017/2025). Pick your age and sex, and the table below shows what each standard recommends — and where they disagree.
The EU value uses μg RE (retinol equivalent), an older unit definition than the μg RAE (retinol activity equivalent) used by the other three standards — the numbers are not directly interchangeable.
The EU protein value is given per kilogram of body weight (g/kg/day), not as a flat daily amount like the other three standards.
Japan's folate figure is labeled in μg without an explicit DFE conversion in the source table; treat cross-system comparison for folate as approximate.
How to read RDA, AI, UL, and EAR
Recommended Dietary Allowance (RDA) is the intake that meets the needs of nearly all healthy people in an age and sex group. Adequate Intake (AI) is used instead when there isn't enough evidence to set an RDA. Estimated Average Requirement (EAR) is the amount that meets the needs of half the group, and is the base used to calculate the RDA. Tolerable Upper Intake Level (UL) is the highest daily amount unlikely to cause harm — it is not a target, and it is not automatically dangerous to go over it on a single day.
How to use this calculator
- Enter your age and select your sex.
- Choose which of the four standards you want to compare.
- Read the recommended amount (RDA or AI) and upper limit for each of the 7 nutrients.
- Check the footnotes for nutrients where the definition or unit differs between standards, such as Vitamin A and protein.
Why official numbers differ between countries
| Factor | What it affects |
|---|
| Reference body weight | Protein and some mineral RDAs are derived per kilogram of body weight, then converted to a flat gram amount using each population's average reference body weight. |
| Sun exposure assumptions | Vitamin D adequate intake accounts for expected skin synthesis from sunlight, which each committee assumes differs by latitude and lifestyle. |
| Dietary intake surveys | Committees partly set requirements from what a well-nourished population is observed to eat, so local food patterns and survey data feed into the number. |
| Statistical method and safety margin | RDA is typically the Estimated Average Requirement plus two standard deviations; committees vary in how they estimate that variation and in the uncertainty factor applied to the upper limit. |
| Evidence review date | Standards are revised roughly every five years as new studies appear, so a nutrient revised in 2024 can differ from one last revised in 2011. |
FAQ
Why is the US iron RDA for women 18 mg but Korea's is 12 mg?
The two committees used different evidence reviews and different assumptions about menstrual iron loss and dietary absorption when calculating the Estimated Average Requirement, which is the basis for the RDA.
Which standard should I follow if I live outside these four regions?
This tool only covers the four systems it could verify against primary official sources. If your own country publishes its own dietary reference values, that is the most relevant standard for you.
What does 'AI' mean instead of 'RDA'?
AI (Adequate Intake) is used when there isn't enough evidence to calculate an Estimated Average Requirement. It is set from observed intake in a healthy population instead of a calculated requirement.
Why does the EU protein number look so different?
EFSA expresses protein as grams per kilogram of body weight per day (0.83 g/kg/day for adults), while the other three standards give a flat daily gram amount already calculated for an average adult body weight.
Is exceeding the upper limit (UL) dangerous?
The UL is the highest chronic daily intake unlikely to cause adverse effects in most healthy people. Occasionally going over it on a single day is not the same as chronic excess intake, but sustained intake above the UL is not recommended without medical supervision.
These figures are population-level reference values for healthy people, not a personal prescription. An individual's actual requirement can be higher or lower depending on health status, medications, pregnancy, and other factors. This tool does not cover infants, children, or pregnancy/lactation values, and it makes no claims about disease prevention or treatment.
Sources: NIH ODS / National Academies — Dietary Reference Intakes, 2011 Calcium & Vitamin D report (summary table), NCBI Bookshelf — DRI Reference Tables (Vitamin A, C, Iron, Folate, Protein), Korea Ministry of Health and Welfare / Korean Nutrition Society — 2025 Dietary Reference Intakes for Koreans, Summary, Japan Ministry of Health, Labour and Welfare — Dietary Reference Intakes for Japanese (2025), EFSA — Summary of Dietary Reference Values, version 4 (2017), EFSA — Overview on Tolerable Upper Intake Levels, version 11 (Aug 2025)