Calorie Deficit Calculator
Last updated: October 15, 2026
Estimate a daily calorie deficit and projected weekly weight change from maintenance calories and intake.
Estimated daily calorie deficit
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- Weekly calorie deficit: —
- Weekly energy equivalent, not predicted weight loss: —
- Four-week energy equivalent, not predicted weight loss: —
On this page
Quick summary: Estimate a daily calorie deficit and projected weekly weight change from maintenance calories and intake.
Read the method, example and limitations
Updated reference sections in this guide are in English.
Guide language: English. Updated October 15, 2026.
What this calculator estimates
Calorie Deficit Calculator
Inputs and units
Use the units shown for Estimated maintenance calories per day, Planned daily calorie intake, Days following the plan each week, Static energy conversion assumption (calories per pound). Required fields cannot be blank. Use zero only where that field and the model allow it. Select Calculate after changing a scenario.
Method and assumptions
Daily energy difference is estimated maintenance calories minus entered intake. Multiply by selected days per week. Dividing that weekly difference by the entered calories-per-pound assumption gives a static energy equivalent; multiply it by four for a four-week equivalent.
Worked example
A 500-calorie daily difference for seven days gives 3,500 calories. At an assumed 3,500 calories per pound, that is one pound of energy equivalent, not a promise of one pound of weight loss.
Limitations
Body-weight changes are not linear conversions of calorie deficits: metabolism adapts, and water and body composition vary. This tool does not prescribe calorie intake or forecast physiological weight loss. A negative difference is an energy surplus.