Calorie (TDEE) Calculator
Estimate the calories your body uses each day. Enter your details and activity level to get maintenance calories, plus rough targets for losing or gaining weight. Educational estimate only — not medical or nutritional advice.
Example: with Age 30 yrs · Height 5 ft · Weight 170 lb · Activity level Moderate: exercise 4-5x/week → Maintenance calories: 2,693 cal.
- Lose ~0.5 lb/week2,443 cal
- Lose ~1 lb/week2,193 cal
- Lose ~2 lb/week1,693 cal
Computed by the calculator below using its default values. Change any input to see your own numbers.
For safety, calorie targets below about 1,200 (women) or 1,500 (men) per day are not recommended without medical supervision — the 2 lb/week loss target may hit this floor for smaller or less active people.
Daily calories
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How the estimate works
This uses the Mifflin-St Jeor equation to find your Basal Metabolic Rate (calories at rest), then multiplies by an activity factor to get your Total Daily Energy Expenditure (TDEE). A deficit of about 500 calories a day roughly targets one pound of loss per week; a surplus does the reverse. These are starting estimates — real needs vary, so consult a professional before making big changes.
How it’s calculated
BMR is calculated using one of three selectable formulas: Mifflin-St Jeor (default), Revised Harris-Benedict, or Katch-McArdle (uses body fat % instead of age/height). BMR is then multiplied by one of six activity factors — Sedentary (1.2), Light (1.375), Moderate (1.55), Active: daily or intense 3-4x/week (1.65), Very Active (1.725), or Extra Active (1.9) — to estimate TDEE. The goal table shows maintenance plus ±0.5, ±1, and ±2 lb/week targets (roughly ±250/±500/±1,000 cal/day, since a pound of fat is about 3,500 calories), with a safety-floor warning below about 1,200 cal/day (women) or 1,500 cal/day (men). A small converter also cross-converts calories and kilojoules using 1 kcal = 4.1868 kJ.
Results update as you type and are estimates, not professional advice — verify important decisions with a qualified professional.
Sources: Mifflin-St Jeor equation; Revised Harris-Benedict equation; Katch-McArdle formula; 1 kcal = 4.1868 kJ (international steam table calorie).
Common mistakes
- Overstating activity level, which inflates the target.
- Treating the estimate as exact for everyone.
Frequently asked questions
What is TDEE?
Total Daily Energy Expenditure — the calories you burn per day including activity. Eating at TDEE maintains weight.
Why 500 calories for a pound?
A pound of fat is roughly 3,500 calories, so a ~500/day deficit approximates a pound a week. Bodies are not perfectly linear, so results vary.
Is this medical advice?
No. It's an educational estimate. Talk to a doctor or registered dietitian before starting a weight program.
Mifflin-St Jeor vs Harris-Benedict vs Katch-McArdle: which should I use?
Mifflin-St Jeor is the most widely validated for the general population and is the default here. Revised Harris-Benedict is an older alternative that tends to run slightly higher. Katch-McArdle uses body fat percentage instead of age, so it can be more accurate if you know your body fat — but only as accurate as that body fat number.
Why is there a safety floor on the -2 lb/week target?
Very low calorie intakes — below about 1,200 cal/day for women or 1,500 cal/day for men — make it hard to get enough nutrients and are not recommended without medical supervision. Smaller or less active people are more likely to hit this floor at a 2 lb/week deficit.
How do I convert calories to kilojoules?
Multiply calories (kcal) by 4.1868 to get kilojoules, or divide kJ by 4.1868 to get kcal. Food labels in many countries outside the US show kJ alongside or instead of calories.