What is BMI? How to Calculate Your BMI (and try ClearTools’ free BMI calculator)

Quick: BMI (body mass index) is a simple height-to-weight ratio used to screen whether an adult is underweight, healthy weight, overweight, or obese. Use our fast calculator to get your number: ClearTools BMI Calculator.

What exactly is BMI?

BMI = weight (kg) ÷ height (m)². It’s an easy screening measure used worldwide to estimate whether body weight may be putting someone at higher health risk.

How to calculate (quick example)

Metric: If you weigh 70 kg and are 1.75 m tall → BMI = 70 ÷ (1.75 × 1.75) = 22.9. U.S. units: BMI = (weight in pounds ÷ height in inches²) × 703.

BMI categories for adults (what the number means)

Underweight: < 18.5
Normal / healthy weight: 18.5 – 24.9
Overweight: 25.0 – 29.9
Obesity: ≥ 30.0 (with higher classes by higher BMI values)

These cutoffs are standard for adults and are commonly used in public-health guidance.

Important limits — why BMI isn’t the whole story

BMI is a screening tool, not a diagnosis. It doesn’t measure body fat distribution, muscle vs fat, or fitness. Athletes with lots of muscle may have a “high” BMI even when healthy, and older adults with low muscle may have a “normal” BMI but higher risk. Use BMI together with waist measurements and risk factors for a fuller picture.

Children & teens

For ages 2–19, BMI is interpreted using age-and-sex percentiles rather than adult cutoffs — so don’t use adult ranges for kids. Use a child/teen calculator or consult a provider.

Why use the ClearTools BMI Calculator?

Try the ClearTools BMI Calculator to get an instant result, suggested category, and clear next steps. The calculator:

accepts metric & imperial units
shows the BMI category and a short explanation
is easy to share — great for social and referral traffic

How to use the calculator (2 simple steps)

Open the calculator: cleartools.net/bmi-calculator
Enter your height and weight → tap “Calculate” → read your BMI and suggested next steps

What to do with your BMI result

If your BMI is outside the healthy range, consider tracking waist circumference, activity levels, diet, and risk factors (blood pressure, blood sugar). Talk to a health provider for personalised advice — BMI is one piece of the puzzle.

Quick tips (for readers & site SEO)

Add a clear CTA button near the top: Try the BMI Calculator linking to /bmi-calculator/.
Localize: offer an Amharic snippet or phrase and include “Ethiopia” in the page title or H2 for local search traffic.
Offer a downloadable PDF of results (email capture) to turn visitors into subscribers.

Try it now: https://cleartools.net/bmi-calculator/

Sources: CDC (how BMI is calculated / units), StatPearls (BMI adult cutoffs), NCBI review (BMI strengths & limits), and NHLBI guidance on combining BMI with waist & risk factors for best assessment.