Calorie Deficit Calculator — How Many Calories to Lose Weight

What is this calculator?

A calorie deficit calculator determines the daily calorie deficit required to achieve a target weight loss goal. It uses your Total Daily Energy Expenditure (TDEE) and a safe weekly loss rate to compute the necessary reduction in calorie intake, ensuring sustainable weight loss.

Formula

Example

For a person with current weight 80 kg, target weight 70 kg, TDEE 2500 kcal, and weekly loss goal 0.5 kg: daily deficit = (0.5 * 7700) / 7 ≈ 550 kcal, daily target = 2500 - 550 = 1950 kcal, total deficit = 0.5 * 7700 = 3850 kcal, weeks to goal = (80 - 70) / 0.5 = 20 weeks.

How to use

1. 1Enter your current weight (kg), target weight (kg), and Total Daily Energy Expenditure (TDEE in kcal). Then select your desired weekly weight loss goal from the dropdown (0.25, 0.5, 0.75, or 1.0 kg per week).
2. 2Click Calculate. The tool applies the calorie deficit formula to compute your daily deficit, daily calorie target, total deficit needed, and estimated weeks to reach your goal.
3. 3Review the outputs: Daily Calorie Deficit shows how many calories to cut each day; Daily Calorie Target is your new daily intake; Weeks to Goal estimates the duration; Total Calorie Deficit is the cumulative deficit required. Use these to plan your diet and track progress.