Should I use this for medical decisions?

This calculator is for informational purposes only and should not replace professional medical advice. Always consult with a healthcare provider for medical decisions.

Can I solve for different variables?

Yes! This calculator supports reverse solving. You can solve for: Weight, Height, BMI.

What units can I use?

This calculator supports multiple unit systems. Select your preferred units from the dropdown menus next to each input field.

BMI Calculator

Calculate Body Mass Index (BMI) from weight and height

Formula shown2 inputs definedUpdated Nov 2025By CalcuTotal TeamFree, no sign-up

Quick Summary

Use this when you need:

Get accurate results in seconds
Track health metrics
Solve for any unknown variable

You’ll need:Weight, Height

You’ll get:BMI

How this is calculated

The formula is always visible so you can verify the math and explain your numbers to anyone who asks.

What these terms mean

Weight

Weight used in the calculation.

Height

Height used in the calculation.

BMI

BMI used in the calculation.

When to use this calculator

Use this calculator when you need to quickly compute bmi calculator with accurate, verified formulas.

Last updated: November 19, 2025

BMI calculator explained

Body Mass Index (BMI) divides weight by height squared to approximate body fat for adults. This calculator works in metric or imperial units, solves for any variable (BMI, weight, or height), and lists the standard CDC classification ranges.

How the conversion works

BMI is:

BMI = \\frac{\\text{weight (kg)}}{\\text{height (m)}^2}

If you enter pounds or inches, the tool converts to metric internally. Rearranged versions solve for weight ( $\\text{kg} = BMI \\times h^2$ ) or height ( $h = \\sqrt{\\text{kg} / BMI}$ ).

Units and conversions

Input	Accepted units	Notes
Weight	kg, lb	Pounds convert via $kg = lb / 2.20462$ .
Height	m, cm, ft/in	Centimeters divide by 100 to get meters; feet/inches convert to meters automatically.
BMI	kg/m²	Output is dimensionless but derived from SI units.

Worked examples

Metric adult
70 kg at 1.75 m:

BMI = 70 / 1.75^2 = 22.86

Target weight
Desired BMI 22 at 1.75 m:

\\text{weight} = 22 \\times 1.75^2 = 67.4\\ \\text{kg}

Tips and pitfalls

BMI is a screening tool; muscular individuals can register as overweight despite low body fat.
Use age- and sex-specific growth charts for children rather than adult cutoffs.
Pair BMI with waist circumference or body composition testing for a fuller risk assessment.
Consult a healthcare professional before acting on BMI results, especially if you are pregnant, elderly, or athletic.

References and further reading

Frequently Asked Questions

Medical Disclaimer

This calculator is for informational and educational purposes only and should not be considered medical advice.

The results provided are estimates based on the information you enter and should not be used as a substitute for professional medical advice, diagnosis, or treatment.

Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay in seeking it because of something you have calculated here.

If you think you may have a medical emergency, call your doctor or emergency services immediately.

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Calculator info

Version:: v1.0.0
Last reviewed:: Nov 13, 2025
Sensitivity:: high
References:: 2

High-sensitivity calculator

This calculator involves health decisions. Results are for informational purposes only. Consult a licensed healthcare provider before making medical decisions.

Last updated: November 19, 2025

BMI calculator explained

How the conversion works

BMI is:

BMI = \\frac{\\text{weight (kg)}}{\\text{height (m)}^2}

If you enter pounds or inches, the tool converts to metric internally. Rearranged versions solve for weight ( $\\text{kg} = BMI \\times h^2$ ) or height ( $h = \\sqrt{\\text{kg} / BMI}$ ).

Units and conversions

Input	Accepted units	Notes
Weight	kg, lb	Pounds convert via $kg = lb / 2.20462$ .
Height	m, cm, ft/in	Centimeters divide by 100 to get meters; feet/inches convert to meters automatically.
BMI	kg/m²	Output is dimensionless but derived from SI units.

Worked examples

Metric adult
70 kg at 1.75 m:

BMI = 70 / 1.75^2 = 22.86

Target weight
Desired BMI 22 at 1.75 m:

\\text{weight} = 22 \\times 1.75^2 = 67.4\\ \\text{kg}

Tips and pitfalls

BMI is a screening tool; muscular individuals can register as overweight despite low body fat.
Use age- and sex-specific growth charts for children rather than adult cutoffs.
Pair BMI with waist circumference or body composition testing for a fuller risk assessment.
Consult a healthcare professional before acting on BMI results, especially if you are pregnant, elderly, or athletic.

Quick Summary

Calculator Tool

How this is calculated

What these terms mean

Weight

Height

BMI

When to use this calculator

BMI calculator explained

How the conversion works

Units and conversions

Worked examples

Tips and pitfalls

References and further reading

Frequently Asked Questions

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Medical Disclaimer

Was this calculator helpful?

Found an error?

Calculator info

BMI calculator explained

How the conversion works

Units and conversions

Worked examples

Tips and pitfalls

References and further reading

Frequently Asked Questions

Related Calculators

Detention time

Neutralization

Saponification value

cm Height Conversion Calculator

Height Converter

Height in Inches Calculator

Was this calculator helpful?

Found an error?

Calculator info