Calorie Calculator: BMR and Daily Energy Needs
Estimate your basal metabolic rate and the calories you need a day at your activity level, with the Mifflin-St Jeor or Harris-Benedict equation, the FAO/WHO/UNU equations, or Japan's and Korea's dietary reference intakes.
How the estimates are made
- Mifflin-St Jeor (1990): 10 × weight (kg) + 6.25 × height (cm) − 5 × age + 5 for men, − 161 for women.
- Harris-Benedict: 66.473 + 13.7516 × weight + 5.0033 × height − 6.755 × age for men; 655.0955 + 9.5634 × weight + 1.8496 × height − 4.6756 × age for women. Japan's NIHN equation: (0.0481 × weight + 0.0234 × height − 0.0138 × age − 0.4235, or − 0.9708 for women) × 1,000 ÷ 4.186.
- FAO/WHO/UNU (2004): BMR from weight by age band and sex (Schofield equations). Daily needs = BMR × the physical activity level (PAL): 1.53, 1.76 or 2.25, the examples the report gives for its three lifestyles.
- Japan (DRI 2025): BMR = the reference value per kg for your age and sex × weight; daily needs = BMR × 1.50, 1.75 or 2.00 (1.70 and 1.90, or 1.40 and 1.70, at older ages).
- Korea (KDRIs 2025): the estimated energy requirement from age, weight and height with one of four activity coefficients. The published tables use the "low active" level and round down to 100 kcal.
- All of these give averages for healthy adults. Your real needs can differ by 10% or more; illness, pregnancy, breastfeeding and growth change them.
- Everything runs in your browser. What you enter is not sent to LeedyBox or saved.
Source: Mifflin et al., Am J Clin Nutr 1990;51:241-7 (PubMed); FAO/WHO/UNU: Human energy requirements (2004), table 5.1 · Last checked:
Source: 厚生労働省「日本人の食事摂取基準（2025年版）」策定検討会報告書 エネルギー（表2）; FAO/WHO/UNU: Human energy requirements (2004), table 5.1 · Last checked:
Source: FAO/WHO/UNU: Human energy requirements (2004), tables 5.1-5.3 · Last checked:
Wrong result? If a figure looks wrong for a method, email us the method and what you entered, so we can check it against the source.
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How to use
- Choose your sex, enter your age, and your height and weight in centimetres and kilograms or in feet, inches and pounds.
- Pick a method. The page starts with the usual method for your language; every method works on every page.
- Read your basal metabolic rate, the energy your body uses at rest, and the daily needs at each activity level.
- Choose the activity level that fits a normal week, not your most active day. The hint under each level describes it.
Frequently asked questions
What is BMR?
Basal metabolic rate is the energy your body uses at complete rest to keep breathing, circulating blood and holding its temperature. It is usually the largest part of the calories you burn each day.
How many calories do I need a day?
Roughly your BMR times your physical activity level. A woman of 35, 165 cm and 60 kg has a Mifflin-St Jeor BMR of about 1,295 kcal, so about 1,980 kcal a day with a sedentary or light lifestyle (PAL 1.53).
Why do the methods give different numbers?
They come from different groups of people and use different inputs: Mifflin-St Jeor uses height and age, the FAO/WHO/UNU equations only weight and age band, Japan's standard a value per kilogram, and Korea's the US/Canada equation for total needs. Differences of 100 kcal or more are normal.
Which method should I use?
For a quick personal estimate Mifflin-St Jeor is widely used. Use Japan's or Korea's standard when you want the same basis as the official tables of that country, for example for school or workplace meals.
Can I use this to lose weight?
It shows estimated maintenance needs, not a diet plan. Real needs vary from person to person, so ask a doctor or dietitian before cutting calories, especially with a health condition.
Is what I enter sent anywhere?
No. The calculation runs in your browser, and the page does not save what you enter.