Calorie Deficit Calculator: Intake from Maintenance
Calculate the intake implied by a maintenance estimate and a daily calorie deficit, without promising a weight-loss date.
Your inputs
Choose the units and assumptions that match your data. Example inputs are illustrative.
Your result
Enter your values, then choose Calculate.
Results are calculated in your browser. Display rounding does not change the underlying calculation.
Calculation breakdown
Method, assumptions and worked example
How it works
Implied daily intake = maintenance estimate − entered deficit. Deficit percentage = deficit ÷ maintenance × 100. A seven-day energy difference is seven times the entered daily deficit.
Worked example
Maintenance of 2,500 kcal/day with a 300 kcal deficit implies 2,200 kcal/day, a 12% deficit and a seven-day energy difference of 2,100 kcal.
Using the result
A fixed calories-per-kilogram rule cannot accurately forecast an individual weight-loss timeline. Energy expenditure adapts, and water weight fluctuates. This tool does not convert the deficit into promised weight loss. Under-1,000-calorie targets are blocked, but no software threshold makes an intake suitable for everyone. For adults only; not for children, pregnancy, breastfeeding, or individualized clinical nutrition. A clinician or registered dietitian can account for medical conditions, medications and athletic demands.
Frequently asked questions
Can I enter a zero deficit?
Yes. The result then equals your entered maintenance estimate.
Why is there no target-weight date?
A fixed arithmetic deficit is not a reliable physiological weight-change model.
Method review and references
Formula and content reviewed on 10 October 2026. Worked examples are hypothetical. Methods and assumptions are explained on each page. Health estimates are not clinical measurements; symbolic tools are for entertainment.