TDEE Calculator

Your total daily energy expenditure is your resting rate multiplied by an activity factor: 1.2 if you barely move, 1.375 for one to three sessions a week, 1.55 for three to five, 1.725 for six or seven, 1.9 for an athlete. The resting rate below uses Mifflin-St Jeor. Both are stated in full further down.

Sex

Age: 30 years

1580

Height

centimetres

Weight

kilograms

Activity Level

How this is calculated

Two steps, and both of them are printed here in full. First, resting metabolic rate comes from the Mifflin-St Jeor equation: for men, 10 × weight in kilograms + 6.25 × height in centimetres − 5 × age + 5; for women the same three terms and then − 161 instead of + 5. That equation was the most accurate of the common predictive formulas in the systematic review that compared them, in obese and non-obese adults alike — and "most accurate" there still means within 10 percent for roughly four people in five, so the output is a starting estimate rather than a measurement.

Second, that figure is multiplied by an activity factor to reach total daily energy expenditure. The five the calculator offers are the conventional set: 1.2 for sedentary, 1.375 for light activity of one to three days a week, 1.55 for moderate activity of three to five days, 1.725 for very active six or seven days, and 1.9 for an athlete or a physically demanding job. Those multipliers are a convention rather than a measurement of anybody, and they are the largest source of error in the whole calculation — one step up the list adds several hundred calories a day. If you are between two, take the lower one and let the scale correct you over a fortnight.

The calorie goals under the result are simple arithmetic on the same number: 550 below maintenance for about half a kilogram of loss a week, 1,100 below for about a kilogram, maintenance itself, and 300 above for a lean gain. Those deficits come from roughly 7,700 calories per kilogram of body tissue, which is a linear rule of thumb that over-predicts loss the longer you run it, because a smaller body burns less.

Where this comes from

1. A new predictive equation for resting energy expenditure in healthy individuals — Mifflin et al., American Journal of Clinical Nutrition, 1990 (PubMed)
2. Comparison of predictive equations for resting metabolic rate in healthy nonobese and obese adults: a systematic review — Frankenfield et al., Journal of the American Dietetic Association, 2005 (PubMed)
3. Body Weight Planner — National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), National Institutes of Health

Nothing on this site is medically reviewed — it cites its sources so you can check them. Read our editorial policy. Method last checked 21 August 2026.

Understanding how many calories your body burns each day is essential for anyone combining intermittent fasting with weight management. Your TDEE gives you a concrete number to work with, whether your goal is fat loss, maintenance, or muscle gain.

When you pair TDEE awareness with intermittent fasting, you gain two powerful levers: controlling when you eat and how much you eat. Many people find that fasting naturally reduces calorie intake, but knowing your TDEE ensures you are hitting the right target rather than guessing.

Frequently Asked Questions

What is the difference between TDEE and BMR?

BMR (Basal Metabolic Rate) is the number of calories your body burns at complete rest just to keep you alive. TDEE adds your daily activity, exercise, and the thermic effect of food on top of BMR. TDEE is always higher than BMR and represents your true daily calorie burn.

Which TDEE formula is the most accurate?

The Mifflin-St Jeor equation is considered the most accurate for most people and is the standard used by dietitians. It tends to be within 10% of measured values. For highly muscular individuals, the Katch-McArdle formula using lean body mass can be more precise.

How does activity level affect my TDEE?

Activity level is multiplied against your BMR, so it has a significant impact. A sedentary person might burn 1,800 calories daily while a very active person of the same size could burn over 2,800. Be honest about your activity level for the most accurate result.

Should I eat below my TDEE to lose weight?

Yes, eating below your TDEE creates a calorie deficit which is required for weight loss. A moderate deficit of 300-500 calories below TDEE is generally recommended for sustainable fat loss without excessive muscle loss or metabolic slowdown.

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