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Estimate BMI and adult BMI category using the standard kg/m² formula.
Quick answer: BMI Calculator
BMI = weight in kilograms divided by height in metres squared. It is an adult screening measure, not a complete health assessment.
Example: A person weighing 75 kg at 175 cm has BMI = 75 / (1.75 x 1.75) = 24.5, which falls in the standard healthy range of 18.5-24.9.
Calculations follow the documented formula on this page; rounding and input units can change the last digit-treat outputs as educational estimates unless you reconcile with source systems.
* This is an estimate. Actual amounts may vary slightly based on input assumptions.
BMI classifies weight relative to height using WHO/NHS adult bands. It does not measure body fat, muscle, or fat distribution, so athletes and older adults need extra context.
Estimate BMI and adult BMI category using the standard kg/m² formula.
Inputs on this page: Weight (kg), Height (cm). Assumptions stay visible so you can reproduce the figure elsewhere.
Long-form walkthroughs that pair well with this calculator. When you need narrative context beyond the live fields, start here and return to the tool to plug in your own numbers.
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Read guide →Adults use this for routine health checks, personal trainers use it for baseline screening, clinicians use it as an initial measure, and insurers may use it during underwriting. It should be read alongside waist circumference, health history, and professional advice.
Continue in the Calculators category hub, the Utility tools collection, or the glossary. Related calculators in this session: Daily Calorie Calculator, BMI for Children Calculator, Percentage Calculator, Tip Calculator, Recipe Scaling Calculator, Baking Ingredient Substitution Tool.
The Formula
BMI = weight_kg ÷ height_m²| This tool | BMI = weight_kg ÷ height_m² |
|---|---|
| Related intent: bmi calculator | See paired tools for bmi calculator-each page documents its own core relationship next to the live form. |
| Related intent: body mass index | See paired tools for body mass index-each page documents its own core relationship next to the live form. |
Core relationship for BMI Calculator:
BMI = weight_kg ÷ height_m²
Worked check: 75 kg at 175 cm → BMI = 75 / (1.75²) = 24.5 (standard healthy range 18.5–24.9).
Keep the same assumptions and open a neighbor calculator when your question branches: Daily Calorie Calculator, BMI for Children Calculator, Percentage Calculator, Tip Calculator. Each page documents its own formula beside the fields.
Learning links: Methodology · Editorial policy · Glossary
A person weighing 75 kg at 175 cm has BMI = 75 / (1.75 x 1.75) = 24.5, which falls in the standard healthy range of 18.5-24.9.
Re-enter the same numbers in the calculator above to confirm the page math matches the interactive result.
Adults use this for routine health checks, personal trainers use it for baseline screening, clinicians use it as an initial measure, and insurers may use it during underwriting. It should be read alongside waist circumference, health history, and professional advice.
Instant response
Run BMI Calculator in the browser and read the breakdown beside the form.
Transparent formula
The formula and worked example on this page match what the calculator uses.
Privacy friendly
No account required; inputs stay in your session unless you choose to share them.
Cross-device ready
Layout works on mobile, tablet, and desktop for the same field labels.
Official references for context. Calculator outputs are planning estimates—confirm material decisions with the primary authority or a qualified professional. See our methodology and editorial policy.
Reviewed July 18, 2026 · Content stamp 2026-07-18
Click a question to expand the answer.
Yes, the BMI Calculator is completely free with no hidden limits. For BMI Calculator, keep the inputs you used beside the result so the number can be checked later. The documented formula is BMI = weight_kg ÷ height_m², and small changes to rates, rounding, dates, tax rules, regional assumptions, or percentage bases can change the final bmi calculator result. Treat the output as a planning reference and confirm high-stakes decisions against official guidance or source systems.
Yes. All tools are optimized for desktop, tablet, and mobile devices. For BMI Calculator, keep the inputs you used beside the result so the number can be checked later. The documented formula is BMI = weight_kg ÷ height_m², and small changes to rates, rounding, dates, tax rules, regional assumptions, or percentage bases can change the final bmi calculator result. Treat the output as a planning reference and confirm high-stakes decisions against official guidance or source systems.
Adult BMI = weight(kg) ÷ height(m)²; it is a screening number, not a full health diagnosis. For BMI Calculator, keep the inputs you used beside the result so the number can be checked later. The documented formula is BMI = weight_kg ÷ height_m², and small changes to rates, rounding, dates, tax rules, regional assumptions, or percentage bases can change the final bmi calculator result. Treat the output as a planning reference and confirm high-stakes decisions against official guidance or source systems.
75 kg at 175 cm → BMI = 75 / (1.75²) = 24.5 (standard healthy range 18.5–24.9). For BMI Calculator, keep the inputs you used beside the result so the number can be checked later. The documented formula is BMI = weight_kg ÷ height_m², and small changes to rates, rounding, dates, tax rules, regional assumptions, or percentage bases can change the final bmi calculator result. Treat the output as a planning reference and confirm high-stakes decisions against official guidance or source systems.
Enter height in metres (1.75), not feet-and-inches typed as 5.10. Children need age/sex percentiles—not adult BMI bands. Pair BMI with waist measure and clinical advice for decisions. For BMI Calculator, keep the inputs you used beside the result so the number can be checked later. The documented formula is BMI = weight_kg ÷ height_m², and small changes to rates, rounding, dates, tax rules, regional assumptions, or percentage bases can change the final bmi calculator result. Treat the output as a planning reference and confirm high-stakes decisions against official guidance or source systems.
No. Treat this as a planning estimate. Confirm material decisions with HMRC, IRS, a licensed advisor, or a clinician as appropriate. For BMI Calculator, keep the inputs you used beside the result so the number can be checked later. The documented formula is BMI = weight_kg ÷ height_m², and small changes to rates, rounding, dates, tax rules, regional assumptions, or percentage bases can change the final bmi calculator result. Treat the output as a planning reference and confirm high-stakes decisions against official guidance or source systems.
Compare units, rounding, compounding, and tax basis side by side. This page documents: BMI = weight_kg ÷ height_m² For BMI Calculator, keep the inputs you used beside the result so the number can be checked later. The documented formula is BMI = weight_kg ÷ height_m², and small changes to rates, rounding, dates, tax rules, regional assumptions, or percentage bases can change the final bmi calculator result. Treat the output as a planning reference and confirm high-stakes decisions against official guidance or source systems.
BMI classifies weight relative to height using WHO/NHS adult bands. It does not measure body fat, muscle, or fat distribution, so athletes and older adults need extra context. Formula reference: BMI = weight_kg ÷ height_m² For BMI Calculator, keep the inputs you used beside the result so the number can be checked later. The documented formula is BMI = weight_kg ÷ height_m², and small changes to rates, rounding, dates, tax rules, regional assumptions, or percentage bases can change the final bmi calculator result. Treat the output as a planning reference and confirm high-stakes decisions against official guidance or source systems.
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Reviewed by Toollabz Editorial
Product editor | Last reviewed July 18, 2026
See methodology and editorial policy.