Free · Instant · Shows the math
Calorie Calculator
Daily calories to maintain, lose, or gain weight — from your BMR and activity, with all three equations compared.
Results
- Maintenance (TDEE)
- 2,250 kcal
- Mild loss — 0.25 kg / 0.5 lb per week
- 2,000 kcal
- Loss — 0.5 kg / 1 lb per week
- 1,750 kcal
- Mild gain — 0.25 kg / 0.5 lb per week
- 2,500 kcal
- Gain — 0.5 kg / 1 lb per week
- 2,750 kcal
| Equation | BMR |
|---|---|
| Mifflin-St Jeor | 1,452 kcal |
| Harris-Benedict | 1,492 kcal |
| Day | Calories |
|---|---|
| Day 1 | 1,550 kcal |
| Day 2 | 1,550 kcal |
| Day 3 | 1,550 kcal |
| Day 4 | 1,550 kcal |
| Day 5 | 1,550 kcal |
| Day 6 | 2,250 kcal |
| Day 7 | 2,250 kcal |
Mifflin-St Jeor → TDEE
BMR = 1,452 kcal
TDEE = 1,452 × 1.550 = 2,250 kcal
BMR uses Katch-McArdle when body fat % is supplied, otherwise Mifflin-St Jeor.
A calorie calculator estimates the calories you need each day to maintain, lose, or gain weight. It computes your basal metabolic rate (BMR), multiplies by an activity factor for your total daily energy expenditure (TDEE), then subtracts or adds calories for your goal.
Enter your sex, age, height, weight, and activity level for a maintenance number plus loss and gain targets. Add your body fat percentage to switch from Mifflin-St Jeor to the Katch-McArdle Formula.
How to calculate your calories
To calculate your calories, find BMR, apply an activity factor, then adjust for your goal. A 500-calorie daily deficit produces about 1 pound (0.45 kg) of loss per week; a 500-calorie surplus produces a similar rate of gain.
Worked example: a 30-year-old woman at 68 kg (150 lb) and 165 cm has a BMR near 1,400 kcal. At lightly active (×1.375) her TDEE is about 1,928 kcal — her maintenance number.
Frequently asked questions
Adult women need about 1,600–2,400 calories per day and men about 2,000–3,000, per the U.S. Department of Health. Your number depends on size, age, and activity — the calculator personalizes it.
Yes for a starting point. Mifflin-St Jeor lands within about 10% of measured resting metabolic rate for most healthy adults. Adjust against two weeks of scale data.
No, if you chose your activity level honestly. Workouts are already inside your TDEE, so eating them back double-counts and stalls loss.
Results are estimates based on population averages and are not medical advice. Consult a doctor or registered dietitian nutritionist (RDN) before making large changes to your diet, especially for deficits over 2 lb (0.9 kg) per week, during pregnancy or nursing, or for anyone under 18.