The TDEE formula
Total daily energy expenditure starts from your basal metabolic rate and multiplies it by an activity factor that accounts for everything you do beyond lying still:
BMR = 10·kg + 6.25·cm − 5·age + s (s = +5 men, −161 women)
TDEE = BMR × activity factor
| Activity | Factor |
|---|---|
| Sedentary (little/no exercise) | 1.2 |
| Lightly active (1–3 days/wk) | 1.375 |
| Moderately active (3–5 days/wk) | 1.55 |
| Very active (6–7 days/wk) | 1.725 |
| Extra active (physical job / 2×) | 1.9 |
Worked example
A 30-year-old man, 178 cm, 75 kg, moderately active:
BMR: ≈ 1,718 kcal/day.
TDEE: 1,718 × 1.55 ≈ 2,663 kcal/day to maintain weight.
Cutting and bulking targets
To lose weight, eat below TDEE; to gain, eat above it. A deficit or surplus of about 500 kcal/day changes weight by roughly 0.45 kg (1 lb) per week, since a pound of fat stores about 3,500 calories. The calculator shows a moderate ±500 kcal target for each.
Note: these are estimates. Track your weight over two to three weeks and adjust — if it isn't moving as expected, nudge calories by 100–200 and reassess.