Calorie Calculator

What is a Calorie Calculator?

A calorie calculator estimates how many calories you need each day to maintain your current weight, based on your age, gender, weight, height, and activity level. It uses two key metrics: BMR (Basal Metabolic Rate) and TDEE (Total Daily Energy Expenditure).

Understanding BMR and TDEE

Basal Metabolic Rate (BMR)

BMR is the number of calories your body burns at complete rest—just to keep you alive (breathing, circulation, cell production). It accounts for 60-75% of your total daily calorie burn.

Total Daily Energy Expenditure (TDEE)

TDEE is your total daily calorie needs. It includes:

• BMR (calories at rest)
• Activity (exercise, movement)
• Thermic effect of food (digestion)

TDEE = BMR × Activity Multiplier

The Mifflin-St Jeor Equation

Our calculator uses the Mifflin-St Jeor equation, widely considered the most accurate for BMR:

Men (BMR) = 10 × weight(kg) + 6.25 × height(cm) - 5 × age + 5

Women (BMR) = 10 × weight(kg) + 6.25 × height(cm) - 5 × age - 161

Example

A 30-year-old woman, 165 cm tall, 60 kg: BMR = (10 × 60) + (6.25 × 165) - (5 × 30) - 161 = 600 + 1031 - 150 - 161 = 1,320 calories/day at rest

With moderate activity (1.55×): TDEE = 1,320 × 1.55 = 2,046 calories/day

Activity Level Multipliers

Level	Multiplier	Description
Sedentary	1.2	Little or no exercise, desk job
Light	1.375	Exercise 1-3 days/week
Moderate	1.55	Exercise 3-5 days/week
Active	1.725	Exercise 6-7 days/week
Very Active	1.9	Intense daily exercise, physical job

Using Your Results

To Lose Weight

Create a deficit of 250-500 calories per day for a safe loss of 0.25-0.5 kg per week.

To Maintain Weight

Eat around your TDEE.

To Gain Weight

Add 250-500 calories per day for a safe gain of 0.25-0.5 kg per week.

Important Notes

• Estimates only: Individual metabolism varies. Use these numbers as a starting point.
• Track and adjust: Monitor your weight over 2-4 weeks and adjust calories as needed.
• Don’t go too low: Women should rarely go below 1,200; men below 1,500 calories per day.
• Combine with BMI: Use our BMI calculator for a fuller health picture.

Frequently Asked Questions

How accurate is this calculator?

The Mifflin-St Jeor equation is the gold standard and typically within 5% of measured BMR for most people.

Why do I need to know my weight and height?

BMR formulas use these to estimate your body’s energy needs. Larger bodies need more energy.

Does muscle burn more calories than fat?

Yes. Muscle is more metabolically active. A person with more muscle can have a higher BMR at the same weight.

Can I use this for weight loss?

Yes. Subtract 500 calories from your TDEE for about 0.5 kg per week loss. Always consult a healthcare provider before dieting.

Note: This calculator provides estimates for educational purposes. Actual calorie needs vary. Consult a healthcare provider or dietitian for personalized advice.