Calorie Deficit Calculator
Enter your maintenance calories and a target weekly weight loss rate to find the daily calorie deficit and target calorie intake needed.
Your calculation is performed in your browser.This result is an estimate for informational and educational purposes. It isn’t a diagnosis and isn’t a substitute for advice from a doctor, registered dietitian, or other qualified professional. See our methodology and sources for the formula used and its limitations.
How it works
The calculator converts your target weekly weight loss into an equivalent number of calories using the standard energy value of body fat, then divides that by seven to get the daily calorie deficit needed relative to your maintenance level.
Formula & methodology
About 7,700 calories are stored in 1 kg of body fat (3,500 per pound). A weekly loss rate is turned into a weekly calorie deficit, then spread over 7 days. Your target is never shown below 1,000 calories per day.
Weekly deficit = Weekly loss × Calories per unit of fatDaily deficit = Weekly deficit ÷ 7Target calories = Maintenance calories − Daily deficitDeficit % = Daily deficit ÷ Maintenance × 100What each term means
- Weekly loss
- Planned loss per week, in kg or lb.
- Calories per unit of fat
- 7,700 per kg, or 3,500 per lb.
- Maintenance calories
- Calories needed to hold your weight steady.
Worked example
With maintenance calories of 2,400 and a target loss of 0.5 kg per week, the daily deficit is about 550 calories, giving a target of roughly 1,850 calories per day.
Common uses
- —Translating a weekly weight loss goal into a concrete daily calorie number to hit.
- —Checking whether a planned deficit is realistic and sustainable rather than too aggressive.
- —Working backward from a target date to see what daily deficit is required.
Important notes
- —Don't know your maintenance calories? Use the TDEE Calculator first to estimate them from your BMR and activity level.
- —For safety, the calculator caps the weekly loss rate at 1.5 kg (or about 3 lb) per week.