Calorie deficit and surplus

A calorie deficit is eating less than your TDEE; a calorie surplus is eating more. A sustained deficit drives weight loss, a sustained surplus drives weight gain — two sides of the same energy-balance mechanism.

A calorie deficit means eating less in a day than you burn (less than your TDEE); a calorie surplus means eating more. A sustained deficit leads to weight loss, a sustained surplus to weight gain — both are two sides of the same mechanism, energy balance.

In Cookrange, the day’s target is set against this balance, but the target itself doesn’t change on its own during the day: calories burned (including NEAT), read from your phone’s health data, show up as a passive number on top of that day’s fixed target. Widening the deficit or surplus is something you do by asking Cookrange AI to regenerate your plan.