Weight loss calculator
Find out in seconds how long it will take to reach your goal weight and what daily calorie deficit you need. Tell us your current weight, target and pace; we compute the weeks, the estimated date and the calories to cut each day.
You will reach your goal in
20 weeks
Estimated date: November 18, 2026
10 kg
To lose
-550
kcal/day less
Renzy applies that deficit and tracks it for you: photograph your food and see if you are on track each day.
Estimate at ~7700 kcal per kg of fat. Real loss is not linear (it slows near the goal). ~0.5 kg/week is the most sustainable pace.
How is time to lose weight calculated?
Each kg of body fat is about 7700 kcal. To lose 0.5 kg per week — the most sustainable pace — you need roughly a 3850 kcal weekly deficit, i.e. about 550 kcal/day below your expenditure (TDEE). We multiply your chosen pace by 7700 for the deficit and divide the kilos to lose by the weekly pace for weeks and date. Note: real loss is not perfectly linear — it slows as you approach your goal — so treat it as a roadmap, not a stopwatch.
FAQ
How much can I safely lose per week?
0.5-1% of body weight per week (for most, 0.5-0.8 kg). Faster usually means losing muscle and water, more hunger and rebound.
How much deficit to lose 1 kg?
About 7700 kcal of accumulated deficit per kg of fat. Over a week, 1 kg needs ~1100 kcal/day, which is a lot — so 0.5 kg/week (~550 kcal/day) is more realistic.
Why do I stall on the same deficit?
As you lose weight, expenditure drops, so the same deficit does less over time. Recalculate your calories every 4-6 kg lost or after a 2-3 week stall.
Can I speed it up without being hungry?
Raise protein and food volume (veg), move more (steps) and sleep well to hold the deficit comfortably. Huge deficits rarely work long term.