TDEE Calculator – Calculate Your Total Daily Energy Expenditure
Working out how much energy you burn in a day is the first step of almost every nutrition plan. Your TDEE — total daily energy expenditure — adds together resting metabolism, the cost of digesting food, and everything you spend on walking, working and training.
Once that figure is on the table, decisions get simpler. Fat loss means eating under it, muscle gain means eating over it, and staying put means hovering around it. Guessing tends to end with stalled progress; a measured starting point usually does not.
How Our Calculator Works
The tool estimates your resting metabolic rate with the Mifflin-St Jeor equation, published in 1990 and still the default recommendation in sports nutrition practice. It takes your age, height, weight and biological sex and returns the calories your body would burn even if you stayed in bed all day.
That resting figure is then multiplied by an activity factor that reflects a normal week for you. Two people who weigh the same can land far apart: a software developer who lifts three evenings a week burns noticeably less than a roofer who trains daily, and the multiplier is where that difference shows up.
The outcome is your maintenance calorie level. Spend more than it and you gain; spend less and you lose. Our companion maintenance calorie calculator breaks that number down further, and the macronutrient calculator turns it into grams of protein, carbs and fat.
How To Use This Result
- Fat loss: aim 300–500 calories below your TDEE. That pace protects muscle far better than crash diets, and it is easier to keep up socially.
- Muscle gain: add roughly 200–400 calories. A slow surplus keeps most of the weight lean instead of padding the midsection.
- Maintenance or recomposition: eat at maintenance, keep protein high and let training drive the change in body composition.
- Check again later: metabolism adapts. Re-run the numbers every 4–6 weeks or after a 5 lb swing.
A calculator gives you a target, not a verdict. Compare its prediction with what the scale does over two or three weeks, then adjust intake by 100–200 calories if reality disagrees.
Frequently Asked Questions
Is TDEE 100% accurate?
No. It is a well-tested estimate, not a lab measurement. Muscle mass, hormone levels, sleep debt and even stress can push real-world burn 5–10% either way. Treat the output as day one of an experiment and refine it using your own results.
What activity level should I choose?
Pick the one that describes an ordinary week, not your most impressive one. Sedentary covers desk work with little training, moderately active means structured training three to five days a week, and very active means hard sessions six or seven days. When in doubt, choose the lower option.
Do I need to recalculate after losing weight?
Yes. A lighter body costs less energy to run, so your maintenance calories drop as you diet. Recalculating every few weeks stops a deficit from quietly shrinking into maintenance.
Should training-day calories differ from rest-day calories?
You can do it, but most people do better keeping intake steady and averaging across the week. Only athletes training several hours a day usually need meaningful day-to-day swings.
Mifflin-St Jeor or Katch-McArdle — which is better?
Katch-McArdle tends to be closer for people who know their body fat percentage, since it works from lean mass. Add your body fat in the optional field and the calculator reports both so you can compare.
Results come from published population equations and are estimates only — they are not medical advice. See our disclaimer.
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Maintenance Calorie Calculator – Find Your Daily Calorie Maintenance Level
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Body Fat Percentage Calculator – Estimate Your Body Fat
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