Calorie Deficit Calculator
A free, browser-based calculator. Runs entirely in your browser — no sign up, nothing stored.
Enter details
Result
Fill in the fields to see your result.
Estimate only — not medical or nutritional advice. Individual needs vary; consult a professional before making big changes.
How to use this calculator
- Enter sex, age, height, current weight and activity.
- Add your target weight and timeframe in weeks.
- Read the daily calorie target and weekly change.
How it works
Uses ~7,700 kcal per kg: daily change = (target − current) × 7,700 ÷ (weeks × 7). Target intake = TDEE + that change. Big rates trigger a safety note.
Worked example
Lose 5 kg in 10 weeks (TDEE 2,500). ≈ 550 kcal/day deficit → about 1,950 kcal/day (0.5 kg/week).
Tips
- Estimate only — not medical or nutritional advice. Individual needs vary.
Frequently asked questions
Is fast weight loss safe?
Losing more than ~1 kg/week is hard to sustain and can be unsafe — the tool warns you and suggests a longer timeframe.
Privacy?
Runs entirely in your browser. Your inputs are not saved or transmitted.
Related tools
Tip: Enter any known values to calculate the remaining results.
All calculations run in your browser. Your inputs are never saved or transmitted.