What is a calorie deficit?
A calorie deficit means eating fewer calories than your body burns, which forces it to use stored fat for energy. It's the fundamental mechanism behind all weight loss. This planner finds your maintenance calories (TDEE), then subtracts the deficit needed for your chosen weekly rate.
How big should your deficit be?
- 0.25 kg/week (~275 cal/day deficit) — slow, easy to sustain, best for lean people
- 0.5 kg/week (~550 cal/day) — the popular "sweet spot" for most people
- 1 kg/week (~1,100 cal/day) — aggressive; only sensible with a lot to lose
Because 1 kg of fat holds about 7,700 calories, your weekly rate simply divides into a daily deficit.
Why is slow weight loss recommended?
Faster loss risks muscle loss, low energy, and rebound weight gain. Slower deficits are easier to stick to and keep more of your hard-earned muscle.
Will weight loss keep this pace forever?
No — as you get lighter your TDEE falls, so recalculate every 4–5 kg to stay on track.