Calorie deficit calculator
How many calories you'd need to cut daily to hit your goal weight by your target date. Includes a sanity check on whether the timeline is realistic.
Daily target
1635
kcal/day
Deficit
−500
kcal/day
Aggressive — risks muscle loss
Consider extending timeline to 25 weeks for sustainable loss.
AskCalories
Track meals with editable AI estimates
Use a photo, type what you ate, or dictate into chat. Review the estimated portions, calories, protein, carbs, fat, and fiber before saving.
How it works
- Calculate TDEE from your stats and activity level (Mifflin-St Jeor)
- Pounds to lose × 3,500 = total calorie deficit needed
- Total ÷ days in timeline = daily deficit
- TDEE − daily deficit = your daily calorie target
What's a sustainable deficit?
- 250 kcal/day: easy, very slow (~0.5 lb/week loss)
- 500 kcal/day: sustainable for most (~1 lb/week)
- 750 kcal/day: aggressive but workable for higher body fat
- 1,000+ kcal/day: typically unsustainable, increases muscle loss
Don't go below your BMR
If your daily target falls below your BMR, the timeline is too aggressive. Extend the timeline or add cardio for a smaller dietary cut. Sustained eating below BMR drives muscle loss and metabolic adaptation.