Calorie & TDEE Calculator: Find BMR, Macros & Deficit
Estimate your BMR, maintenance calories (TDEE), and daily calorie targets to lose, maintain, or gain weight, with a balanced macro split. Everything runs locally in your browser.
How this calculator works
- It estimates your BMR (basal metabolic rate) with the Mifflin-St Jeor formula, or the Katch-McArdle formula when you add a body fat percentage.
- It multiplies your BMR by an activity factor (1.2 for sedentary up to 1.9 for very active) to get your TDEE, the calories you burn on a normal day.
- For weight goals it adds or subtracts energy from your TDEE. A pound of fat is about 3,500 calories and a kilogram about 7,700, so a 500 calorie daily deficit is close to a pound a week.
- The macro split divides your goal calories into protein, carbohydrate, and fat, using 4 calories per gram for protein and carbs and 9 calories per gram for fat.
Example: a 30 year old man, 175 cm and 70 kg, lightly active, has a BMR near 1,649 and a TDEE near 2,267 calories. A 500 calorie deficit is about 1,767 calories a day to lose close to a pound a week.
Calorie calculator FAQ
How many calories should I eat a day?
It depends on your age, sex, height, weight, and activity level. This calculator estimates your maintenance calories, then adds or subtracts energy for your goal. As a rough guide many adults maintain on roughly 2,000 to 2,500 calories a day, but your own number can be higher or lower, so enter your details for a personal estimate.
How many calories are in a pound?
A pound of body fat stores roughly 3,500 calories, and a kilogram stores roughly 7,700 calories. That is why a deficit of about 500 calories a day adds up to close to one pound of fat loss per week. Real results vary because the body also adjusts as you lose weight.
What is a calorie deficit?
A calorie deficit means eating fewer calories than your body burns in a day, which pushes it to use stored energy and lose weight. A deficit of 250 to 500 calories a day is a common and sustainable starting point. Eating more than you burn is a surplus, which is used to gain weight.
What is the difference between BMR and TDEE?
BMR, or basal metabolic rate, is the energy your body uses at complete rest just to stay alive. TDEE, or total daily energy expenditure, is your BMR multiplied by an activity factor to include movement and exercise. TDEE is the number to compare your food intake against, because it reflects a normal day.
How accurate is this calculator?
The Mifflin-St Jeor and Katch-McArdle formulas are well established, but every estimate is approximate, usually within about 10 percent for most people. The biggest source of error is the activity level, since it is self reported. Treat the result as a starting point, track your weight for two to three weeks, and adjust your calories if needed.