Calorie Deficit Calculator

Q: What is a calorie deficit?

It occurs when you consume fewer calories than your body burns. It is the fundamental principle for weight loss.

Q: How much weight can I lose?

A deficit of 500 calories per day typically results in about 0.5 kg (1 lb) of weight loss per week, which is considered healthy and sustainable.

Q: Should I eat less than my BMR?

Generally no. Eating too little can slow down your metabolism and cause muscle loss. Ideally, create the deficit through a combination of diet and exercise.

Calculate your maintenance and deficit calories for weight loss

Weight (kg)

Height (cm)

Age (years)

Gender

Activity Level

Formula Explanation

This calculator uses the Mifflin-St Jeor equation, considered one of the most accurate for estimating Basal Metabolic Rate (BMR).

The Equation

For Men:
(10 × weight) + (6.25 × height) - (5 × age) + 5

For Women:
(10 × weight) + (6.25 × height) - (5 × age) - 161

Example

Weight Loss Example

Profile: Male, 30 years, 180cm, 90kg, Sedentary (factor 1.2)

1. Calculate Basal Metabolic Rate (BMR):

BMR = (10 × 90) + (6.25 × 180) - (5 × 30) + 5

BMR = 900 + 1125 - 150 + 5 = 1880 kcal

2. Calculate Maintenance (BMR × Activity):

Maintenance = 1880 × 1.2 = 2256 kcal

3. Apply Deficit:

Goal = 2256 - 500 = 1756 kcal/day to lose weight.

Frequently Asked Questions

What is a calorie deficit?

How much weight can I lose?

Should I eat less than my BMR?