Lose 10 kg in 20 weeks
By Jesús Narváez Tamés ·
From 85 to 75 kg in about five months. What daily deficit it takes and why this pace holds up better than rushing.
550kcal/day
0.50 kg/week
- Current weight
- 85 kg
- Target weight
- 75 kg
- Timeframe
- 20 weeks
Ten kilos is the most common goal, and 20 weeks is a time frame most people can manage without living on a diet. The figure above is the average daily deficit needed to go from 85 to 75 kg in that time, counting roughly 7,700 kcal per kilo of fat.
That number is an average. In the first weeks the scale drops faster through water and glycogen, and in the middle it can stall even when you do everything right. Watch the four-week trend, not the daily reading, and keep protein high so what you lose is fat.
How this was calculated
1 kg of body fat ≈ 7700 kcal. Daily deficit is (kg × 7700) / days. Past roughly 0.5–1% of body weight per week it gets hard to sustain.
Nearby values
The same calculation changing only the timeframe. The highlighted row is this example.
| Timeframe | Result | |
|---|---|---|
| 6 weeks | 1833 kcal/day | 1.67 kg/week |
| 13 weeks | 846 kcal/day | 0.77 kg/week |
| 20 weeks | 550 kcal/day | 0.50 kg/week |
| 27 weeks | 407 kcal/day | 0.37 kg/week |
| 34 weeks | 324 kcal/day | 0.29 kg/week |
Adjust it to your numbers
The calculator starts from this example. If you change a field, that value is saved only on this device.
Weekly loss speed
0.59 % / wk → Optimal
To preserve muscle mass, stay between 0.5% and 1% of body weight per week. Above 1.5% increases the risk of sarcopenia and fatigue.
Want to know what to eat with this deficit?
Generate a sample daily menu hitting your target macros.
Open the calculator without this example
Frequently asked questions
How long does it take to lose 10 kg?+
Dropping from 85 to 75 kg in 20 weeks takes a 550 kcal/day deficit. At a sustainable pace, four to six months. Faster usually costs muscle and comes back.
What calorie deficit do I need to lose 10 kg?+
Dropping from 85 to 75 kg in 20 weeks takes a 550 kcal/day deficit. It depends on the time frame. Over 20 weeks it is the daily deficit above; stretch the time frame and it drops.
Worked examples
A specific profile, with the number already done. Open it if it looks like you, then adjust.