How to use Calorie Calculator

The short answer

To work out daily calories, ClickZM estimates your BMR with the Mifflin-St Jeor equation, multiplies it by your activity level, then adds or subtracts about 7,700 kcal per kg of weekly weight change. Example: a 30-year-old man, 70 kg, 175 cm, lightly active needs about 2,270 kcal to maintain.

It runs in your browser. What you enter is not uploaded.

How to use it

Enter your values in the fields; defaults show a worked example.

Pick the units or options that apply to you.

Read the result, which updates instantly as you type.

Check the formula note under the result to see exactly how it was worked out.

Limits worth knowing

How many calories should I eat to lose weight? About 500 kcal below maintenance loses roughly 0.5 kg (1 lb) a week. Avoid going below 1,200 (women) or 1,500 (men) without medical advice.

How accurate is it? Equations are within about 10% for most people. Track your weight for 2–3 weeks and adjust.