Calorie deficit scenario calculator

Compare a user-selected reduction with an estimated maintenance baseline. The result is an intake scenario, not a recommendation or a predicted rate of weight loss.

Starting estimate

Maintenance estimate sourceEstimate with DRI 2023Enter an estimate I already have

Age (years, 19+)Life stage for this modelChoose life stageNot pregnant or breastfeedingPregnant or breastfeeding

Measurement unitsUS · inches and poundsMetric · centimeters and kilograms

Height (in)Weight (lb)Reference equationChoose equationMaleFemaleDaily activity categoryChoose categoryInactiveLow activeActiveVery active

Activity means your whole daily routine, including work, travel, chores and leisure. It is not just the number of workouts. Use the 2023 reference categories. The model assumes a weight-stable adult and does not measure your metabolism.

Your scenario

Enter a reduction to explore, or zero for a maintenance scenario. The tool does not choose a reduction for you. Changing reduction units clears the amount.

Reduction (kcal/day)Reduction unitskcal/dayPercent

Use exampleClear

Enter an age in years.

This tool does not display intake scenarios below 1,000 kcal/day, following a boundary in the NIDDK planner. It is not a universal safe minimum or approval of a higher scenario. No values are silently raised to that boundary.

Example inputs are hypothetical. Displayed numbers are rounded independently. Arithmetic uses unrounded values. No inputs are saved, sent with analytics or transferred to Nourmio.

Start from an estimate you can identify

Choose either the adult DRI 2023 estimate or an existing maintenance estimate that you enter. The output names its source. An entered number is not independently verified by the calculator.

Both routes are limited to adults aged 19 or over, outside pregnancy or breastfeeding. Entering a manual baseline does not bypass those limits. The equation route uses the same method as the daily energy calculator.

Choose a scenario without assigning a target

For a kcal reduction, the formula is intake scenario = maintenance estimate − reduction. For a percentage, first multiply the estimate by the selected percent divided by 100, then subtract that reduction.

Zero reduction gives a maintenance scenario. The tool does not select a deficit for everyone. It does not turn a fixed energy gap into a promised number of pounds lost or a date for reaching a weight.

As a hypothetical arithmetic example, a baseline of 2,000 kcal/day and a selected reduction of 300 kcal/day give 1,700 kcal/day. A selected 15% gives the same arithmetic result. These are not recommended inputs or an intake prescription.

Changing reduction units clears the amount. A number in kcal/day must not silently become the same number in percent. Changing the baseline can also change the meaning of a percentage scenario, so check the source and values together.

Understand the display boundary

The tool does not display intake scenarios below 1,000 kcal/day. NIDDK’s Body Weight Planner uses that lower boundary for its goals. It is not a universal safe minimum and it does not make a higher scenario suitable for you.

A value below the boundary produces a message rather than a silently increased intake. The comparison uses the unrounded result. Rounding a lower value to 1,000 does not make it an accepted scenario.

Separate arithmetic from an eating plan

The result does not assess your medical history, nutritional needs or whether weight loss is appropriate. Discuss an appropriate plan with a qualified health professional. A numerical scenario alone cannot establish those decisions.

If you keep food notes in Nourmio, review the food and portion amounts separately. The repeated-meals guide explains keeping routine entries consistent. This calculator does not save your inputs or transfer a calorie target into the app.