BMI (Body Mass Index) is a measure of body fat based on height and weight. It is calculated as weight in kilograms divided by height in meters squared.

What are the BMI categories?

Underweight: below 18.5. Normal weight: 18.5 to 24.9. Overweight: 25 to 29.9. Obese: 30 or higher. These ranges apply to adults aged 20 and older.

BMR (Basal Metabolic Rate) is the number of calories your body needs to maintain basic functions like breathing and circulation at complete rest. It is calculated using the Mifflin-St Jeor equation.

TDEE (Total Daily Energy Expenditure) estimates how many calories you burn per day based on your BMR and activity level. It helps with planning calorie intake for weight loss, maintenance, or gain.

Is BMI accurate for everyone?

BMI is a general screening tool and does not account for muscle mass, bone density, or body composition. Athletes and older adults may get less accurate readings. Consult a healthcare provider for personalized advice.

sigxlabs/Calculators

BMI Calculator

Calculate Body Mass Index (BMI), BMR, and TDEE. Supports metric and imperial units.

bmi calculator

tdee calculator

calorie calculator

bmr calculator

Height (cm)

Weight (kg)

Age (years, for BMR/TDEE)

Gender (for BMR)

How to use

1
Choose your units
Switch between metric (cm, kg) and imperial (inches, lbs) using the toggle.
2
Enter your height and weight
Type your height and weight in the input fields. BMI updates instantly.
3
Optional: add age and gender
Enter your age and select your gender to calculate BMR (Basal Metabolic Rate).
4
Optional: set activity level
Choose your activity level to calculate TDEE (Total Daily Energy Expenditure).
5
Review your results
See your BMI, weight category, BMR, and TDEE with color-coded feedback.

FAQ

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