What this tool does
You enter today’s body (height and weight come from the unit toggle), a goal weight, and a weekly kilogram pace. The calculator estimates TDEE, sizes a deficit to match that pace (capped), applies the educational calorie floor, and divides the gap to goal by the pace for a week count.
How it works
Daily deficit ≈ weekly kg × 7,700 / 7, then converted to a percent of TDEE and capped near 25%. Weeks = |current − goal| / weekly kg. Imperial users enter goal pounds; the form keeps metric math internally. The week count assumes the pace never changes, which it will.
Formula and methodology
TDEE from Mifflin-St Jeor × activity. Desired daily deficit = weeklyKg × 7700 / 7. Target = max(TDEE − deficit, educational floor). Weeks ≈ |weight − goalKg| / weeklyKg. Pace is clamped to 0.15–0.75 kg/week so the UI cannot request a crash.
How to interpret the result
A 12-week line is a calendar sketch. Plateaus, vacations, and adaptation stretch it. If the floor fired, you wanted a pace this page will not fully fund — slow the weekly kg instead of starving. Keep protein in the deficit range.
Example
80 kg toward 75 kg at 0.4 kg/week is about 13 weeks on paper. If TDEE is 2,760 kcal, that pace wants a sizable daily gap; the engine may cap the percent so you do not print an extreme cut. Re-run when the weekly average actually lands near 75 kg, not when one morning says 76.4.
Common mistakes
- A goal weight copied from a BMI chart for someone else’s height.
- 0.75 kg/week on a 60 kg body — that is a large fraction of weight, not a hobby.
- Forgetting to update current weight after you have already lost 4 kg.
- Treating the week count as a deadline you must punish yourself to hit.
When this estimate may be off
- Goal weight is below a healthy range for your frame and the tool cannot know that.
- Weekly kg is a wish, not a deficit you will actually eat.
- Edema, medication, or cycle water dominate the scale.
- TDEE is wrong because activity was theater.