Weight Loss Calculator
Pick a goal weight and a weekly pace, and see the date you'll get there — plus the daily calorie deficit it takes.
Your results
Support your cutHow long will it take to lose the weight?
This weight loss calculator projects the date you'll reach your goal weight from your chosen weekly pace — and tells you the daily calorie deficit that pace requires. Putting a date on the goal turns "I want to lose 10 kg" into a plan you can actually follow.
How it works
A kilogram of body fat stores roughly 7,700 kcal (the metric version of the classic 3,500 kcal per pound, first quantified by Wishnofsky in 1958). Your weekly pace therefore maps to a daily deficit: 0.5 kg per week ≈ 550 kcal per day. The calculator divides your total loss by your pace to project the finish date.
Real-world caveat: as you get lighter, your body burns fewer calories, and metabolism adapts slightly downward during long diets. Expect the last stretch to be slower than the projection — that's physiology, not failure.
What's a safe rate of weight loss?
Research on athletes suggests losing around 0.5–1% of body weight per week preserves muscle and performance far better than crash dieting; a study by Garthe and colleagues found slower rates retained significantly more lean mass. High protein (see our protein calculator) and resistance training are the other two muscle-protection levers.
Frequently asked questions
Why has the scale stopped moving?
Water masks fat loss constantly — sodium, carbs, stress and training soreness all swing daily weight by a kilogram or more. Judge progress on the weekly average, waist measurements and photos, not single weigh-ins.
Should I keep cutting calories when I plateau?
First confirm it's a real plateau (three-plus weeks of flat weekly averages). Then either trim another 100–200 kcal, add daily steps, or take a one-to-two-week diet break at maintenance — all three work.
References
- Wishnofsky M. Caloric equivalents of gained or lost weight. Am J Clin Nutr. 1958;6(5):542–546.
- Garthe I, Raastad T, et al. Effect of two different weight-loss rates on body composition and strength and power-related performance in elite athletes. Int J Sport Nutr Exerc Metab. 2011;21(2):97–104.
Related
These results are estimates for healthy adults and are not medical advice. Consult a health professional before making major changes to your diet or training.
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