Calorie Deficit Calculator
Turn your maintenance calories into a sustainable fat-loss target.
| Pace | % below TDEE | Daily Calories | Weekly Loss |
|---|---|---|---|
| Conservative | 10% | – | – |
| Moderate | 15% | – | – |
| Aggressive | 25% | – | – |
Why Percentage-Based Deficits Beat Fixed Numbers
A flat 500 kcal deficit works differently for a 1,800 kcal TDEE than a 3,200 kcal TDEE — it's a much larger relative cut for the smaller number. This calculator uses percentages of your TDEE instead, so the deficit scales correctly to your body size.
A pound of body fat contains roughly 3,500 kcal, but research shows this rule overestimates real-world results because expenditure declines as weight drops — a process called metabolic adaptation.1
Choosing Your Pace
A 25% deficit loses fat fastest but risks more muscle loss and hunger. A 10% deficit is slower but far easier to sustain and better preserves lean mass — most evidence favors the moderate 15-20% range for typical dieters.2
Frequently Asked Questions
Which pace should I choose?
Moderate (15%) is sustainable for most people and preserves more muscle than aggressive cuts.
Do I need my TDEE first?
Yes — use the TDEE Calculator first if you don't already know your maintenance calories.
Sources
- Hall KD, Chow CC. "Why is the 3,500 kcal per pound weight loss rule wrong?" Int J Obes, 2013;37:1614-1615.
- Thomas DM, et al. "Time to correctly predict the amount of weight loss with dieting." J Acad Nutr Diet, 2014.