World Health Organization Calorie Calculator

The World Health Organization (WHO) provides a standard formula for calculating daily calorie needs based on age, sex, height, and weight. This calculator implements the WHO's recommended approach to help individuals estimate their maintenance calories and adjust for activity levels.

How to Use This Calculator

To get accurate results, enter your personal information in the calculator panel on the right. The calculator requires:

Your age in years
Your sex (male or female)
Your height in centimeters
Your weight in kilograms
Your activity level (sedentary, lightly active, moderately active, very active, or extremely active)

After entering your details, click "Calculate" to see your estimated daily calorie needs. The calculator will display your Basal Metabolic Rate (BMR) and Total Daily Energy Expenditure (TDEE) based on your activity level.

Note: These calculations provide estimates only. Individual calorie needs may vary based on genetics, metabolism, and other factors not accounted for in this formula.

Formula Used

The WHO uses the following formulas to calculate calorie needs:

Basal Metabolic Rate (BMR)

For males:

BMR = 88.362 + (13.397 × weight in kg) + (4.799 × height in cm) - (5.677 × age in years)

For females:

BMR = 447.593 + (9.247 × weight in kg) + (3.098 × height in cm) - (4.330 × age in years)

Total Daily Energy Expenditure (TDEE)

TDEE = BMR × Activity Factor

Activity factors:

Sedentary: 1.2
Lightly active: 1.375
Moderately active: 1.55
Very active: 1.725
Extremely active: 1.9

The calculator applies these formulas to provide personalized calorie estimates. For weight management, you may need to adjust your intake based on your specific goals.

Interpreting Results

The calculator provides two key numbers:

BMR (Basal Metabolic Rate): The number of calories your body needs to maintain basic physiological functions while at complete rest.
TDEE (Total Daily Energy Expenditure): The estimated number of calories you burn each day based on your activity level.

For weight maintenance, aim to consume approximately your TDEE. For weight loss, consume 200-500 calories less per day. For weight gain, consume 200-500 calories more per day.

Important: These are estimates only. Individual results may vary. Consult with a healthcare professional before making significant changes to your diet or exercise routine.

Worked Examples

Example 1: Sedentary Female

Age: 30 years

Height: 165 cm

Weight: 60 kg

Activity Level: Sedentary

BMR = 447.593 + (9.247 × 60) + (3.098 × 165) - (4.330 × 30) = 1,350 calories/day

TDEE = 1,350 × 1.2 = 1,620 calories/day

Example 2: Active Male

Age: 45 years

Height: 180 cm

Weight: 80 kg

Activity Level: Very Active

BMR = 88.362 + (13.397 × 80) + (4.799 × 180) - (5.677 × 45) = 1,800 calories/day

TDEE = 1,800 × 1.725 = 3,105 calories/day

These examples demonstrate how different factors affect calorie needs. The actual numbers will vary based on individual characteristics.

Frequently Asked Questions

Is the WHO formula accurate for everyone?

The WHO formula provides a general estimate, but individual calorie needs can vary based on genetics, muscle mass, and other factors. It's always best to consult with a healthcare professional for personalized advice.

How do I use the TDEE number for weight loss?

To lose weight, consume 200-500 calories less than your TDEE each day. This creates a calorie deficit that your body will use for energy, leading to weight loss over time.

Can I use this calculator for children?

The WHO formula is designed for adults (18 years and older). For children, you should use specialized pediatric growth charts and consult with a pediatrician.

What if I'm pregnant or breastfeeding?

Pregnant and breastfeeding women have increased calorie needs. The WHO provides additional formulas for these specific situations that should be used instead of the general adult formula.