TDEE Calculator

What is TDEE?

TDEE — total daily energy expenditure — is the number of calories your body burns in a day, including workouts and everyday movement. It’s the baseline you adjust to lose fat, maintain weight, or build muscle.

How this calculator works

• Estimates your BMR with the Mifflin-St Jeor equation from age, sex, weight in pounds, and height in inches.
• Multiplies BMR by an activity factor — sedentary through very active — to reach your total daily energy expenditure.
• Adjusts for your goal: 500 kcal below for fat loss, maintenance calories to hold weight, or 300 above to gain.
• Splits the target into protein, fat, and carbs in grams and percentages, so you don’t need a separate macro calculator.

How to use the result

1. Treat the TDEE figure as your maintenance calories: eat that much and your weight should hold steady.
2. If you’re cutting, eat the adjusted target. A 500-kcal cut yields roughly a pound of fat loss per week, but don’t drop below ~1,200 kcal (women) or ~1,500 (men) without medical supervision.
3. Hit the protein number first; it protects muscle in a deficit and keeps you fuller than carbs or fat.
4. Weigh daily, average weekly. If the trend stalls for 2–3 weeks, adjust intake by 100–200 kcal rather than overhauling everything.
5. Recalculate after every 5–10 lbs of change — a lighter body burns less, so yesterday’s target becomes today’s surplus.

How accurate is a TDEE calculator?

For most people, within 10–15%. Mifflin-St Jeor is the most validated formula in clinical use — the same one a standalone BMR calculator runs — but real metabolism shifts with muscle mass, sleep, stress, and incidental movement. Use the number as a starting estimate, then let two to three weeks of scale data decide whether it needs nudging up or down.

Common mistakes

• Overrating activity. A desk job with three gym sessions is usually “light” or “moderate,” not “very active.”
• Eyeballing portions. Unmeasured food is routinely under-reported by 20% or more — enough to erase a 500-kcal deficit.
• Expecting a straight line. Water and glycogen swing body weight several pounds day to day; judge weekly averages, not daily readings.
• Never recalculating. As weight drops, maintenance calories drop with it, and a plateau is often just the math catching up.
• Cutting too hard. A 1,000-kcal deficit speeds up the first two weeks, then tanks adherence and muscle — the slower 500-kcal cut usually wins.

The suggested macro split is a starting point, not a rulebook — if you want to shift protein up or carbs down, a percentage calculator quickly shows what share of your daily calories each macro occupies.