BMR & TDEE Calculator
Calculate your BMR and TDEE with the Mifflin-St Jeor equation. Find your daily calories to maintain, cut or bulk. Free, accurate and private.
This BMR & TDEE calculator tells you two of the most important numbers in fitness. Your BMR (Basal Metabolic Rate) is the energy your body burns at complete rest just to stay alive — breathing, pumping blood, keeping warm. Your TDEE (Total Daily Energy Expenditure) is your BMR plus everything else you do: walking, fidgeting, working out and digesting food. TDEE is your real daily calorie need.
Get this number right and everything downstream gets easier. Eat below your TDEE and you lose fat; eat above it and you gain weight; eat around it and you maintain. We use the Mifflin-St Jeor equation, which research has repeatedly found to be the most accurate of the common predictive formulas.
Calculate your daily calories
What your TDEE is made of
Most of your daily burn — typically 60–70% — is just your BMR. The rest comes from NEAT (non-exercise activity like walking, standing and fidgeting), the calories burned during exercise, and the thermic effect of food (TEF), the energy used to digest what you eat. Protein has the highest TEF, which is one reason higher-protein diets help with fat loss.
Turning your TDEE into a goal
| Goal | Daily calories | Expected change |
|---|---|---|
| Aggressive cut | TDEE − 750 | ~0.7 kg/week (use only short-term) |
| Standard cut | TDEE − 500 | ~0.45 kg (1 lb)/week |
| Maintain | ≈ TDEE | Recomposition over time |
| Lean bulk | TDEE + 250–350 | ~0.25 kg/week, minimal fat gain |
Predictive equations get most people within ~10%. Treat your TDEE as a starting point: track your weight for 2–3 weeks, and if it isn't moving the way you want, adjust calories by 150–250 and reassess. Your body is the final referee, not the formula.
Next steps
Once you know your calories, set your protein target (the most important macro), then read how to lose fat or how to build muscle depending on your goal. Pair any calorie target with resistance training so the weight you lose is fat, not muscle.
Sources & further reading
- Mifflin MD, St Jeor ST, et al. "A new predictive equation for resting energy expenditure in healthy individuals." Am J Clin Nutr. 1990 — PubMed.
- Frankenfield D, et al. "Comparison of predictive equations for resting metabolic rate." J Am Diet Assoc. 2005 — PubMed.
- Centers for Disease Control and Prevention — Finding a Balance of Food and Activity.
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