Calorie deficit calculator
Calculator
The calculator needs JavaScript. The tables below give the same numbers for common cases.
How it is worked out
- Deficit = maintenance − intake = 2,200 − 1,700 = 500.
- About 7,700 kcal per kg (3,500 per lb) of body weight is the common approximation: 3,500 ÷ 7,700 = 0.45 kg a week.
- Real weight loss varies and slows as weight falls; this is an estimate.
| Inputs | Answer |
|---|---|
| Maintenance calories per day: 2200; Calories you eat per day: 1700; Weight to lose: 5 | A deficit of 500 calories a day is about 0.45 kg a week; 5 kg takes about 11 weeks. |
| Maintenance calories per day: 2800; Calories you eat per day: 2300; Weight to lose: 10 | A deficit of 500 calories a day is about 0.45 kg a week; 10 kg takes about 22 weeks. |
| Maintenance calories per day: 1900; Calories you eat per day: 1600; Weight to lose: 3 | A deficit of 300 calories a day is about 0.27 kg a week; 3 kg takes about 11 weeks. |
How to use it
A calorie deficit is maintenance calories minus the calories you eat. The common approximation is 7,700 kcal per kg (3,500 per lb) of body weight, so a 500 kcal daily deficit is about 0.45 kg (1 lb) a week.
Real weight loss is not linear: water shifts, your metabolism adapts and the deficit shrinks as you get lighter. Use the time estimate as a guide and re-check your maintenance calories as your weight changes. This is general information and an estimate, not medical advice; talk to a healthcare professional about your own situation.
Frequently asked questions
How big a calorie deficit is safe?
Moderate deficits, often 250 to 750 calories a day, are common; larger ones should be supervised by a professional.
How long to lose 5 kg?
At a 500 kcal daily deficit about 11 weeks by the 7,700 kcal per kg approximation.
Where do I find my maintenance calories?
Use the TDEE calculator.
Method: standard arithmetic shown step by step; no outside data is used. Checked 2026-11-12.
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General information only. Results are plain arithmetic on the numbers you enter; check anything important (money, health, school work) against your own records or the official source.