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Calculators

How to Calculate Daily Calories

AllinOne Editorial · Published 2026-09-16

Maintenance calories are BMR times activity. A 500 kcal gap is a common planning figure — not a guarantee of 0.5 kg a week.

Daily calorie need is an estimate, not a lab measurement. A widely used adult method is: compute basal metabolic rate (BMR), then multiply by an activity factor to get maintenance calories (TDEE).

Mifflin-St Jeor BMR

Men: 10W + 6.25H − 5A + 5. Women: 10W + 6.25H − 5A − 161. W is weight in kg, H is height in cm, A is age in years. Maintenance = BMR × activity (1.2 sedentary through 1.9 very active on this site).

Worked example

A 30-year-old woman, 165 cm, 62 kg, moderately active has BMR ≈ 1,340 kcal and maintenance ≈ 2,077 kcal. A 500 kcal/day gap would be about 1,577 kcal — a common textbook estimate for roughly 0.5 kg per week, not a promise.

What this will not do

  • It will not prescribe a medical diet or account for pregnancy, illness or athletic training cycles.
  • It will not use child formulas.
  • Activity labels are coarse. If your week is mixed, pick the level you actually sustain.

BMI and calories answer different questions. BMI is a height–weight screen. Calories estimate energy. Use both as starting numbers, not diagnoses.

Frequently asked questions

Which formula does the calculator use?+

Mifflin-St Jeor for adult BMR, then a standard activity multiplier for TDEE.

Should I eat below BMR?+

This tool never suggests a target below estimated BMR. Speak with a clinician before any aggressive deficit.

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