Calorie Deficit Calculator for Weight Loss
Plan a safe daily calorie deficit to hit your target weight by a target date.
About the Calorie Deficit Calculator for Weight Loss
Calorie Deficit Calculator works out the daily calorie shortfall you need to run in order to lose a target amount of weight by a target date. It uses the well-validated figure of ~7,700 kcal per kilogram of body fat.
How to use
- Enter your current weight and goal weight (both in kg).
- Enter the number of weeks until your target date.
- Click Calculate for daily and weekly deficit numbers.
Benefits & key features
- Personalised to your actual weight and time-frame.
- Flags unrealistic targets (>1 kg/week) automatically.
- Honest, evidence-based math — no 'lose 10 kg in a week' fantasy.
- Works with the TDEE calculator for a full eating plan.
Pro tip
A sustainable deficit is 500–750 kcal/day (~0.5-0.75 kg/week). Much faster than that and you'll lose muscle, hair and motivation.