From stats to a daily calorie target
The page first estimates basal metabolic rate with the Mifflin–St Jeor equation, 10 × kg + 6.25 × cm − 5 × age + 5 for men or − 161 for women. It then multiplies by an activity factor between 1.2 (sedentary) and 1.9 (very active) to estimate maintenance calories. The weight-change targets are fixed offsets from that figure:
| Goal | Offset | Approximate rate |
|---|---|---|
| Mild loss | −250 kcal/day | about 0.5 lb (0.23 kg) per week |
| Standard loss | −500 kcal/day | about 1 lb (0.45 kg) per week |
| Mild gain | +250 kcal/day | about 0.5 lb per week |
| Standard gain | +500 kcal/day | about 1 lb per week |
The rates come from the rule of thumb that a pound of body fat holds roughly 3,500 kcal, so 500 kcal a day over seven days is about 3,500 kcal. It is an approximation, since the body adapts as weight changes and not every pound lost is fat.
Worked example
A 60 kg woman, 165 cm, aged 35, with light activity (1–3 days a week): BMR = 600 + 1,031.25 − 175 − 161 = 1,295 kcal. Maintenance = 1,295 × 1.375 = 1,781 kcal. The mild-loss target is 1,531 kcal and the standard-loss target is 1,281 kcal. Protein is shown as 1.6 g per kg of bodyweight, which is 96 g.
Check the result before following it
- Look at the lowest figure. The targets are never clamped, but a warning appears when the standard-loss figure drops below about 1,200 kcal (women) or 1,500 kcal (men), the commonly cited minimums for unsupervised dieting. In the example above, 1,281 kcal sits just above the women's line. Many guidelines advise medical supervision for very low intakes, so consider the milder option. This is general guidance, not medical advice.
- Protein is a bodyweight figure. It is not a share of the calorie total, and it is the only macro this page displays. For the complete carbohydrate and fat split, use the TDEE calculator.
- Recalculate as weight changes. Maintenance calories fall as you get lighter, and rise as you gain.
- General estimate only. It is not medical advice, and the numbers are not suited to children, pregnancy or conditions that affect metabolism.
For how BMI and calorie needs relate, read BMI and daily calorie needs or check your index with the BMI calculator.