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Weight Loss Calculator

Find out when you'll reach your goal weight at a daily calorie deficit, and how much you'll lose each week.

Rules last checked 25 October 2026Every step shown

Your numbers are saved in this browser.
kg
kg
kcal

Eating this many calories less than you burn. 500 a day is about 0.45 kg a week.

Expected to reach your goal

15 April 2027 Thursday

Weeks
22
Loss a week
0.4545 kg

Losing 10 kg with a 500 kcal daily deficit takes about 22 weeks, reaching 75 kg around 15 April 2027.

How it's worked out

  1. Calories to lose10 kg × 7,700 kcal77,000 kcal
  2. Days÷ 500 kcal a day154
  • Weight loss usually slows over time as your body adjusts, so expect it to take a little longer.
  • Ask a doctor before dieting if you are pregnant, diabetic or under 18.

How it works

Days = (current weight − goal) × 7,700 kcal ÷ daily deficit

Worked example

Losing 10 kg, from 85 to 75 kg, needs a deficit of about 77,000 kcal. At 500 kcal a day that's 154 days, about 22 weeks.

Questions people ask

How many calories do I need to cut to lose 1 kg?

About 7,700 kcal, as a rule of thumb. A 500 kcal daily deficit loses about 0.45 kg a week.

What is a safe rate of weight loss?

0.5 to 1 kg a week for most adults. Faster loss is harder to keep up and more likely to come back.

Why does weight loss slow down?

As you get lighter you burn fewer calories, so the same eating plan gives a smaller deficit. The 7,700 kcal rule overestimates loss over long periods.

Formula and rules last checked 25 October 2026Written and tested by the CalculatorDex teamReport a problem