Calorie Calculator
Find your daily calorie needs from BMR and activity (TDEE), with a target for losing, maintaining or gaining weight.
Formula last reviewed 4 August 2026 · How we verify our calculators
Daily calorie target
- Maintenance (TDEE)
- 2,759
- BMR (at rest)
- 1,780
- Est. weekly weight change
- 0
Updates live as you type
Frequently asked questions
We compute your BMR with the Mifflin-St Jeor equation, multiply it by an activity factor to get your TDEE (maintenance calories), then add or subtract your chosen deficit or surplus.
A deficit of around 500 kcal/day targets roughly 0.5 kg of fat loss per week, using the standard approximation of 7,700 kcal per kilogram. Aggressive deficits are best supervised by a professional.
Total Daily Energy Expenditure is the calories you burn in a typical day including activity. Eating at TDEE maintains weight; below it loses, above it gains.
Bodies adapt, water weight fluctuates, and the 7,700 kcal/kg figure is an average. Use the estimate as a guide and adjust based on real-world results.
Three formulas, chained together, into one daily number
80 kg, 180 cm, 30, male, moderate activity (exercise 3–5 days a week) starts with a Mifflin-St Jeor BMR of 1,780 kcal. Multiply that by the moderate-activity factor of 1.55, and maintenance calories — TDEE — comes to 2,759 kcal. Pick "Maintain" and that's the number to target with no expected weekly change. Pick "Lose weight" with the default 500 kcal deficit instead, and the target drops to 2,259 kcal/day, projecting a weekly loss of about 0.45 kg, using the standard approximation that roughly 7,700 kcal corresponds to a kilogram of body fat (500 × 7 ÷ 7,700 ≈ 0.45).
Why it takes three steps to get one number
A single "eat this many calories" figure has to account for three separate things: what your body burns doing nothing (BMR, from the Mifflin-St Jeor equation), what it burns once actual daily activity is layered on (TDEE, via an activity multiplier), and what you're trying to achieve (a deficit to lose, a surplus to gain, or neither to maintain). This calculator runs all three in sequence so you land on a single target instead of having to chain the math yourself.
Where the estimate is solid, and where it's genuinely just an estimate
A 500 kcal daily deficit targeting roughly half a kilogram of weekly fat loss is a widely used, sustainable pace for most people — deficits meaningfully larger than this get harder to sustain and start risking muscle mass and energy levels, which is why they're best attempted under professional supervision rather than by adjusting a slider further. Two things worth knowing about the numbers behind this target: activity-level categories are broad approximations of real movement, not a precise measurement of your day, and the 7,700 kcal-per-kg conversion is a population average that individual bodies deviate from due to water retention and metabolic adaptation over time. Treat the target as a strong starting estimate, then adjust it based on what actually happens on the scale over several real weeks.
This is a general estimate, not medical advice. Consult a doctor or registered dietitian for personalised guidance.