What's the difference between BMR and TDEE?

BMR (Basal Metabolic Rate) is the number of calories your body burns at rest for basic functions like breathing and circulation. TDEE (Total Daily Energy Expenditure) includes BMR plus calories burned through physical activity, exercise, and daily movement. TDEE is what you need to create a deficit from.

How accurate is the Mifflin-St Jeor formula?

The Mifflin-St Jeor equation is considered the most accurate formula for calculating BMR, with studies showing it predicts within 10% of measured metabolic rate for about 70-80% of people. It's more accurate than the older Harris-Benedict equation and is recommended by most nutrition professionals.

What's a safe calorie deficit for weight loss?

A safe calorie deficit is typically 500-1000 calories per day, leading to 1-2 pounds of weight loss per week. Women should generally not go below 1200 calories per day, and men should not go below 1500 calories per day without medical supervision.

Should I eat back calories burned during exercise?

The calculator already accounts for your exercise in the activity level multiplier, so you typically don't need to 'eat back' exercise calories. However, if you do significantly more exercise than usual, you may need to adjust your intake to avoid too large a deficit.

Free Calorie Deficit Calculator

Calculate your daily calorie needs and optimal deficit for healthy, sustainable weight loss

Precise BMR & TDEE

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Calorie Deficit Calculator

Calculate your daily calorie needs and optimal deficit for healthy weight loss

Weight (kg)*

Height (cm)*

Age (years)*

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Activity Level*

Weight Loss Goal*

How to Use the Calorie Deficit Calculator

Our calorie deficit calculator uses scientifically-proven formulas to determine your optimal daily calorie intake for weight loss. Follow these simple steps to get accurate, personalized results.

Select your preferred unit system (Metric or Imperial)

💡 Pro Tip

For the most accurate results, be honest about your activity level and choose a sustainable calorie deficit that you can maintain long-term.

Frequently Asked Questions

A calorie deficit occurs when you consume fewer calories than your body burns. It's the fundamental principle of weight loss - your body must use stored energy (fat) to make up for the deficit, resulting in weight loss. A deficit of 500 calories per day typically leads to about 1 pound of weight loss per week.

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