Weight Loss Timeline Calculator
Estimate how long it will take to reach your goal weight with a daily calorie deficit.
How to use this tool
- Enter current weight, goal weight and daily calorie deficit in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your estimated weeks and the full breakdown beneath it.
1 kg of body fat contains roughly 7,700 kcal. Divide your total fat to lose by your daily deficit to estimate time to goal.
Frequently asked questions
- How many calories are in a kilogram of fat?
- Approximately 7,700 kcal per kg. Some sources use 7,000–7,700; this calculator uses 7,700.
- Is a 500 kcal/day deficit safe?
- A 500 kcal deficit typically produces about 0.5 kg of loss per week, which is within the NHS and WHO recommended range of 0.5–1 kg per week.