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.
CalPilot
Your deficit is set. CalPilot holds you to it.
Log meals by photo or voice and see calories left against your daily target. Free download.
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.