CALCULATOR
Weight Loss Timeline
How long to reach your goal weight at a chosen pace, the daily deficit it needs, and an honest read on whether that pace is too fast.
Roughly 7,700 kcal per kg of body fat. Real loss is never linear; water weight moves first.
How the weight loss timeline is calculated
A kilogram of body fat stores roughly 7,700 kcal. Dividing your chosen weekly rate by seven gives the daily deficit needed to sustain it, and dividing the weight you want to lose by that rate gives the number of weeks.
Real progress is never this linear. Water weight shifts by a kilogram or more day to day, the first weeks of any diet drop faster than the maths predicts, and progress slows as you get lighter because a smaller body burns fewer calories.
Pace matters more than most people expect. Beyond roughly 1% of bodyweight per week, a larger share of what you lose comes from muscle rather than fat, and hunger and training performance both suffer. That is why this calculator flags aggressive rates instead of just printing the date you wanted to see.
The maths behind the timeline
Daily deficit = (weekly rate kg x 7,700) / 7
Weeks to goal = kg to lose / weekly rate
These figures are theoretical. Real fat loss deviates because water weight shifts by a kilogram or more day to day, because early weeks drop faster as glycogen and its associated water fall, and because a lighter body burns fewer calories, so the same intake produces a smaller deficit over time.
Deficit required by pace
| Weekly rate | Daily deficit | Suits |
|---|---|---|
| 0.25 kg | About 275 kcal | Already lean, protecting muscle |
| 0.5 kg | About 550 kcal | Most people, most situations |
| 0.75 kg | About 825 kcal | Higher starting bodyweight |
| 1.0 kg | About 1,100 kcal | Short term only, high bodyweight |
Why pace matters more than the date
A useful ceiling is about 1 percent of bodyweight per week. Above that, a larger share of the loss comes from lean tissue rather than fat, hunger becomes hard to manage, training performance falls, and weight regained afterwards tends to return as fat, leaving composition worse than at the start.
Example: 90 kg to 80 kg
| Pace | Time to goal | Percent of bodyweight per week |
|---|---|---|
| 0.25 kg per week | 40 weeks | 0.28% |
| 0.5 kg per week | 20 weeks | 0.56% |
| 0.75 kg per week | 14 weeks | 0.83% |
| 1.0 kg per week | 10 weeks | 1.11%, above the guideline |
Protecting muscle while you lose
- Keep protein at 1.8 to 2.2 g per kg of bodyweight throughout the deficit.
- Lift at least twice a week. Training is what tells your body which tissue to keep.
- Take diet breaks at maintenance for a week or two if the deficit runs beyond about twelve weeks.
- Expect plateaus. They usually reflect water retention or a smaller body burning less, not failure.
- Judge by weekly averages. Daily fluctuation is mostly water and gut contents.
Frequently asked questions
How fast can I safely lose weight?
Why has my weight loss stalled?
Is a 1000 kcal daily deficit too much?
Do I need to eat back exercise calories?
More tools: all calculators · Full Plan · Recomp · Body fat · Macros · Cheapest whey per 20 g
General information, not medical advice. Consult a qualified professional before changing your diet, especially with a medical condition.