Calories Calculator
Estimate daily calorie needs (BMR and TDEE) based on age, sex, weight, height, and activity level.
About this tool
Whether your goal is losing fat, building muscle, or maintaining weight, it all starts with knowing how many calories your body actually burns each day. The Calories Calculator gives you science-backed estimates to build your nutrition plan around.
How the Calories Calculator works
The Calories Calculator estimates your Basal Metabolic Rate (BMR) using the Mifflin-St Jeor equation — the most accurate predictive formula for the general population. It then multiplies by your activity level to compute your Total Daily Energy Expenditure (TDEE), providing calorie targets for maintenance, fat loss, and muscle gain.
How to use this tool
- Select your sex (male/female) — the Mifflin-St Jeor formula differs slightly.
- Enter your age in years, weight in kilograms, and height in centimeters.
- Select your activity level from the dropdown — be honest, as overestimating activity leads to overestimating calorie needs.
- Click 'Calculate' to see your BMR, TDEE, and calorie targets for different goals.
Common use cases
Setting a daily calorie target for a weight loss diet
Determining maintenance calories to stop weight fluctuations
Calculating a calorie surplus for muscle building
Understanding why weight loss has stalled — you may need to recalculate at your new weight
Examples
- A 30-year-old sedentary male at 80 kg, 178 cm: BMR ≈ 1,789 kcal, TDEE ≈ 2,147 kcal. Fat loss target: ~1,650 kcal/day.
- A 25-year-old moderately active female at 60 kg, 165 cm: BMR ≈ 1,390 kcal, TDEE ≈ 2,155 kcal. Muscle gain target: ~2,450 kcal/day.
Tips & best practices
- These are estimates — use them as a starting point and adjust based on actual weight changes over 2-4 weeks.
- Recalculate your TDEE after every 5-10 kg of weight change — a lighter body burns fewer calories.
- For fat loss, a 300-500 kcal deficit is sustainable. Larger deficits risk muscle loss and metabolic adaptation.
- For muscle gain, a 200-300 kcal surplus is usually sufficient — additional calories primarily add fat, not muscle.
Common mistakes to avoid
❌ Overestimating activity level — 'moderately active' means consistent exercise 3-5 days per week, not walking to the bus stop.
❌ Expecting the calculator to be 100% accurate — individual BMR can vary ±10% due to genetics, body composition, and hormonal factors.
❌ Setting an overly aggressive deficit (1000+ kcal) — this typically backfires through hunger, low energy, and muscle loss.
Frequently Asked Questions
What is BMR?
BMR (Basal Metabolic Rate) is the calories your body burns at complete rest to maintain vital functions like breathing, circulation, and temperature regulation.
What is TDEE?
TDEE (Total Daily Energy Expenditure) is your estimated maintenance calories after applying your activity level to your BMR — the calories you actually burn in a day.
How should I use this for weight loss or gain?
Start with a 300-500 kcal/day deficit for fat loss or a 200-300 kcal/day surplus for lean gain. Track results for 3-4 weeks, then adjust up or down by 100-200 calories.
Related tools
Related guides
In-depth articles to help you learn more about this topic.
Continue Learning
Explore our in-depth guides, browse related tools, or return to the full collection.