Resting calories and daily burn by Mifflin-St Jeor, Harris-Benedict or Katch-McArdle
Runs in your browser. Nothing you type is sent anywhere. Updated on 24 Oct 2026.BMR and TDEE Calculator estimates resting and daily calorie burn. A 30-year-old man of 70 kg and 170 cm has a Mifflin-St Jeor BMR of 1,618 kcal, and 2,507 after a moderate activity multiplier of 1.55. Three equations are offered and the page names whichever one produced your figure.
Pick the Units and Sex, then enter your Age, Weight and Height.
Under The equation, choose Mifflin-St Jeor, Revised Harris-Benedict, or Katch-McArdle with your Body fat percentage.
Under Your week, pick the activity level that matches you, or a custom multiplier.
Read BMR, TDEE and the Loss (-500) and Gain (+500) targets; Share result copies a link.
Basal metabolic rate is not measured here. It is estimated, by an equation fitted to a sample of people, and several such equations exist which disagree by a hundred calories or more about the same body. Naming the one in use is the difference between a figure you can check and a figure you have to trust.
Mifflin-St Jeor is the default, from Mifflin, St Jeor and colleagues in the American Journal of Clinical Nutrition in 1990. For men it is ten times weight in kilograms, plus 6.25 times height in centimetres, minus five times age, plus five; for women the last term is minus 161 instead. It was derived later and on a broader sample than the alternative, and dietetic practice has largely settled on it.
The revised Harris-Benedict equation, from Roza and Shizgal in 1984, is offered too and reads about 50 calories higher for the example above. Katch-McArdle is the third: it uses lean body mass rather than sex and height, so it needs a measured body fat percentage, and it is the better choice for someone who knows theirs.
Total daily energy expenditure multiplies the resting figure by how active the week is. Those multipliers, from 1.2 for a desk job up to 1.9 for twice-daily training, are a convention in wide use rather than a research finding, and no paper fixes them. You can type your own, which is worth doing if you have a physical job or a week that fits none of the steps.
Loss and gain targets are shown 250 and 500 calories either side of maintenance. The deficit is never printed below 1,500 calories for men or 1,200 for women, and the page says when it has clamped rather than showing a number nobody should eat to.
None of this is medical advice, and nothing typed here leaves your browser.
Mifflin-St Jeor is the usual modern choice and the default here. Published in the American Journal of Clinical Nutrition in 1990, it was fitted on a larger and more recent sample than the 1919 Harris-Benedict work, and dietetic practice has broadly adopted it for both non-obese and obese adults.
Basal metabolic rate is what the body burns at complete rest, keeping the heart, brain and organs running. Total daily energy expenditure is that figure multiplied by how active the day is, from 1.2 for a desk job to 1.9 for an athlete, and it is the maintenance number that matters for eating.
A deficit of 500 calories a day below maintenance is the common starting point, implying roughly 0.45 kg a week at 7,700 calories to a kilogram of fat. Real loss runs slower as the body adapts. The page refuses to print a target under 1,500 for men or 1,200 for women.
Moderate activity, usually described as exercise three to five days a week on top of ordinary daily movement. The whole scale, 1.2 through 1.9, is a convention in wide use rather than a published finding, so a custom box is provided for anyone whose week fits none of the five steps.
Only when you have a measured body fat percentage from a scan or calipers, since the equation works from lean mass rather than from sex and height. For a lean person it usually reads higher than Mifflin-St Jeor, and for someone carrying more fat it reads lower, which is the point of it.
Treat them as a starting estimate, not a measurement. Prediction equations carry an error of ten per cent or more for an individual, and activity multipliers are rougher still. The sensible use is to start at the maintenance figure, track weight for a fortnight, and adjust from what actually happens.
Formula only: no rates or limits are read from an official source.
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