Weight loss is mostly arithmetic: eat fewer calories than you burn, consistently. The trick is knowing your real burn rate and choosing a deficit you can actually sustain.
Step 1: find your maintenance calories (TDEE)
Your total daily energy expenditure (TDEE) is the calories you burn in a day — your resting metabolism plus activity. The Calorie Calculator estimates it from your age, sex, height, weight, and activity level using the Mifflin-St Jeor equation. That number is what you'd eat to maintain your current weight.
Step 2: subtract a sensible deficit
A pound of fat is roughly 3,500 calories, so a 500-calorie daily deficit yields about one pound of loss per week — the commonly recommended, sustainable pace. A 250-calorie cut loses about half a pound a week; 750–1,000 pushes toward two pounds but is harder to maintain and risks muscle loss. Don't drop below about 1,200 calories (women) or 1,500 (men) without medical guidance.
Step 3: check your starting point
Knowing whether you're carrying excess body fat helps set a realistic goal. Cross-check with the BMI Calculator and the Body Fat Calculator, and see the resting figure your body needs with the BMR Calculator.
Why the deficit matters more than the diet
No food is magic; the calorie balance is what moves the scale. Whatever eating pattern keeps you in a modest, steady deficit — and keeps you full enough to stick with it — is the right one. Track your weight over a few weeks and adjust the target if progress stalls.