BMI Formula Calculator (Math)

Q: What are the BMI categories?

Underweight < 18.5, Normal 18.5-24.9, Overweight 25-29.9, Obese ≥ 30.

Q: What is the Ponderal Index?

A similar measure: weight(kg) / height(m)³. It accounts for height differently than BMI.

Use our free BMI formula calculator (math version) to compute Body Mass Index from weight and height with a comprehensive mathematical breakdown: the formula, step-by-step calculation, BMI category (WHO standard), healthy weight range, Ponderal Index, and weight needed for normal BMI.

Math

Weight (kg)

Height (cm)

Formula

A math-focused BMI calculator that shows the complete formula breakdown: BMI = weight ÷ (height in meters)², step-by-step arithmetic, WHO category, healthy weight range for normal BMI, weight needed to reach normal range, and Ponderal Index.

BMI = weight(kg) ÷ height(m)²

Percentage: The percentage value you want to apply

Number: The original number or value

Result: The calculated result

How It Works

1Enter your weight in kilograms.
2Enter your height in centimeters.
3Click Calculate to see the full mathematical breakdown.

Examples

70 kg, 175 cm

1.BMI = 70 ÷ (1.75)² = 70 ÷ 3.0625 = 22.9 → Normal weight

Result: 22.9

Frequently Asked Questions

BMI = weight(kg) / height(m)². For imperial: BMI = 703 × weight(lb) / height(in)².

Underweight < 18.5, Normal 18.5-24.9, Overweight 25-29.9, Obese ≥ 30.

A similar measure: weight(kg) / height(m)³. It accounts for height differently than BMI.

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CalculateMe Team

Last updated: 2026-07-15

BMI Formula Calculator (Math)

Formula

How It Works

Examples

70 kg, 175 cm

Frequently Asked Questions

What is the BMI formula?

What are the BMI categories?

What is the Ponderal Index?

Related Calculators

BMI Formula Calculator (Math)

Formula

How It Works

Examples

70 kg, 175 cm

Frequently Asked Questions

What is the BMI formula?

What are the BMI categories?

What is the Ponderal Index?

Related Calculators