Calorie Calculator (TDEE)
Find how many calories you need each day to maintain, lose, or gain weight, based on your body and activity.
Last reviewed July 1, 2026
Estimated with the Mifflin-St Jeor equation. General guidance only — not medical or nutritional advice.
How many calories you should eat depends on your body and how active you are. This calculator estimates your Total Daily Energy Expenditure (TDEE) — the calories you burn in a day — plus targets for losing or gaining weight at a steady, sustainable pace.
Enter your age, sex, height, weight, and activity level. It uses the Mifflin-St Jeor equation, the formula most dietitians consider the most accurate for everyday use.
The Calorie formula
BMR (men) = 10·kg + 6.25·cm − 5·age + 5; BMR (women) = 10·kg + 6.25·cm − 5·age − 161; TDEE = BMR × activity factorkg = weight in kilograms · cm = height in centimetres · age = age in years · activity factor ranges from about 1.2 (sedentary) to 1.9 (very active). Eat below TDEE to lose weight, above it to gain.
Worked example
A 30-year-old woman, 65 kg and 168 cm: BMR = 10×65 + 6.25×168 − 5×30 − 161 = 650 + 1,050 − 150 − 161 = 1,389 calories. At a moderate activity factor of 1.55, TDEE ≈ 2,153 calories a day to maintain weight.
BMR vs. TDEE
Your BMR (Basal Metabolic Rate) is what your body burns at complete rest just to keep you alive. Your TDEE multiplies that by an activity factor to account for movement and exercise — it's the number that actually matters for planning your diet.
To lose weight you eat below your TDEE; to gain, above it. A deficit or surplus of about 500 calories a day corresponds to roughly half a kilogram (about a pound) per week.
Getting a realistic result
Be honest about your activity level — most people overestimate it. If you have a desk job and train a few times a week, 'Light' or 'Moderate' is usually right, not 'Very active'.
This is an estimate, not a prescription. Track your weight over a couple of weeks and adjust: if it's not moving the way you want, nudge your calories up or down.
Frequently asked questions
▶How many calories should I eat to lose weight?
Eat below your maintenance (TDEE). A deficit of about 500 calories a day gives roughly 0.5 kg / 1 lb of loss per week — the calculator shows this target for you.
▶Is the Mifflin-St Jeor equation accurate?
It's widely regarded as the most accurate everyday formula for estimating calorie needs, though individual metabolism varies. Use it as a starting point and adjust based on real results.
▶What is TDEE and how is it different from BMR?
BMR is the calories your body burns at complete rest. TDEE (Total Daily Energy Expenditure) multiplies BMR by an activity factor to include movement and exercise — it's the number that matters for planning your diet.
▶How many calories should I eat to lose or gain weight?
For steady loss, eat about 500 calories below your TDEE for roughly 0.5 kg (1 lb) a week; for gain, eat a similar amount above it. The calculator shows these targets alongside maintenance.
▶What activity level should I choose?
Be honest — most people overestimate. A desk job with a few workouts a week is usually 'Light' or 'Moderate', not 'Very active'. Overstating activity inflates your calorie target.
▶Why do men and women have different calorie needs?
The Mifflin-St Jeor equation adds 5 for men and subtracts 161 for women, reflecting differences in average body composition. Height, weight and age also feed into the result.
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Open calculator →Disclaimer: Calorie Calculator (TDEE) results are estimates for general information and education only, and are not financial, tax, legal or medical advice. Verify important decisions with a qualified professional.