How long it will take to lose the weight you want
Find out in seconds how long it will take to reach your goal weight and what daily deficit you need. This is not a division: we simulate your plan week by week and recalculate your metabolism as you lose weight, so the date already accounts for the slowdown everyone hits halfway.
Sex
Activity
Weekly pace
Estimate using published equations (Mifflin-St Jeor and ~7,700 kcal per kg of fat) with a minimum calorie floor for safety. Not medical advice and no substitute for a professional.
You have your target. Now the hard part
Hitting it daily. Photograph your plate and the app subtracts it from your target — no weighing, no searching.
Next time you sit down to eat, photograph the plate before the first bite. That is the whole method.
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How is time to lose weight calculated?
A kilo of body fat is worth roughly 7,700 kcal. To lose 0.5 kg a week — the pace most people can actually hold — you need a deficit of about 550 kcal a day. The calculator takes your target weight, works out the gap, and turns it into a realistic timeline at a healthy rate, capping the deficit so it never pushes you into territory where you are shedding muscle instead of fat. Two things to expect: the rate slows as you get lighter, because a smaller body burns less, and the scale will wobble by a kilo or two from water and food volume alone. Judge progress over weeks, never day to day.
If your first week comes out at about 2,000 kcal a day, the 2000 calorie meal plan turns that number into a full week of meals in grams, with a 3-meal version.
How long it takes to lose weight: the division vs the real count
The usual sum divides: 10 kg at 0.5 kg a week is 20 weeks. The calculator does something else: it recalculates your expenditure every week with your new weight (a lighter body burns less) and never goes below a calorie floor, your basal metabolic rate × 1.1 (and never under 1,200 kcal for women or 1,400 for men). With light activity, that floor leaves less deficit than 0.5 kg a week needs: about 426 kcal a day for the woman in the table, about 522 for the man. That is why their columns run longer than the division. The woman is the example the calculator already loads (34, 165 cm, 85 kg, lightly active); the man is 34, 178 cm and 95 kg, also lightly active. For your own numbers, enter them above and press “Calculate”.
| Weight to lose | Dividing (0.5 kg/week) | Woman, 85 kg | Man, 95 kg |
|---|---|---|---|
| 5 kg | 10 weeks | 14 weeks | 11 weeks |
| 7 kg | 14 weeks | 19 weeks | 16 weeks |
| 10 kg | 20 weeks | 27 weeks | 22 weeks |
| 15 kg | 30 weeks | 41 weeks | 33 weeks |
| 20 kg | 40 weeks | 56 weeks | 45 weeks |
| 25 kg | 50 weeks | 71 weeks | 57 weeks |
| 30 kg | 60 weeks | 86 weeks | 69 weeks |
Computed with the same function as the calculator: Mifflin-St Jeor, expenditure recalculated every week, about 7,700 kcal per kilo and the app’s calorie floor, at 0.5 kg a week. Thomas et al. (2013) showed that the 7,700 kcal rule without recalculating expenditure overestimates real weight loss. It is a roadmap, not a stopwatch: loss is not linear. These are reference ranges for healthy adults, not a diagnosis or individual advice.
FAQ
How long does it take to lose 10 kg?
Dividing, at 0.5 kg a week it is 20 weeks. With the calculator’s rules (expenditure recalculated every week and a calorie floor), a lightly active 34-year-old woman of 165 cm and 85 kg takes about 27 weeks, and a 34-year-old man of 178 cm and 95 kg about 22. The difference is the floor: with light activity it does not leave the full deficit that 0.5 kg a week needs. With your own numbers, the calculator gives you your week.
How much can you safely lose per week?
Between 0.5% and 1% of your body weight a week — for most people that is 0.5 to 1 kg. Faster than that and an increasing share of what you lose is muscle and water, which is exactly what makes the weight come back.
How big a deficit do I need to lose 1 kg?
Around 7,700 kcal of accumulated deficit per kilo of fat. Spread over a week that is about 1,100 kcal a day for 1 kg/week, which is why that pace is hard to sustain, and about 550 kcal a day for the far more realistic 0.5 kg.
Why have I stalled if I am still in a deficit?
As you lose weight your expenditure falls — you are carrying less and your body adapts — so yesterday's deficit becomes today's maintenance. Recalculate every 4-5 kg. Also check whether the deficit is still real: portion creep is the usual culprit, not metabolism.
Can I speed it up without being hungry?
Raise protein and food volume (vegetables), move more across the day (steps beat extra cardio sessions for most people) and sleep enough — short sleep raises appetite measurably. Cutting harder is the one lever that reliably backfires.
Keep reading
- How fast can you safely lose weight →
- Caloric deficit for beginners →
- How to break a weight-loss plateau →
- Satiating foods to avoid hunger →
- How to keep the weight off →
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