Calorie Calculator for Weight Loss
To lose weight you need a calorie deficit — eating fewer calories than you burn. First find your maintenance calories (TDEE) with the calculator below, then subtract about 500 a day for a sustainable loss of roughly half a kilo a week. This page explains how to set a safe deficit and keep muscle while losing fat.
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Frequently asked questions
How big should my calorie deficit be to lose weight?+
A deficit of 500 calories a day below your TDEE gives about 0.5 kg of fat loss per week, which is sustainable for most people. A 750–1000 deficit loses faster but is harder to maintain and risks muscle loss; don't drop below about 1200 (women) or 1500 (men) calories without medical supervision.
Why am I not losing weight in a calorie deficit?+
Common reasons: under-counting calories (especially oils, sauces and drinks), water retention masking fat loss on the scale, too aggressive a deficit slowing you down, or an overestimated activity level. Track honestly for 2–3 weeks and adjust by 100–200 calories.
How are my daily calories calculated?+
The calculator estimates your Basal Metabolic Rate (BMR) — the energy your body uses at rest — using the Mifflin-St Jeor equation from your age, sex, height and weight, then multiplies it by an activity factor to give your Total Daily Energy Expenditure (TDEE): the calories you burn in a typical day.
What is the difference between BMR and TDEE?+
BMR is what you'd burn lying in bed all day. TDEE is BMR plus the energy you spend moving, exercising and digesting food. To maintain your weight, eat around your TDEE; to lose or gain, adjust from there.
How many calories should I eat to lose or gain weight?+
A deficit of about 500 calories a day below your TDEE leads to roughly 0.5 kg of fat loss per week; a 500-calorie surplus supports a similar rate of gain. Avoid very large deficits, which are hard to sustain and can cost you muscle.
Are these calorie numbers exact?+
No — they're a well-validated estimate. Real needs vary with muscle mass, genetics and daily activity. Use the number as a starting point, track your weight for 2–3 weeks, and adjust by 100–200 calories if you're not moving in your intended direction.