Use this calculator to estimate your Body Mass Index (BMI) and healthy weight range based on your height.
What this height and weight calculator does
This tool gives you a quick estimate of your Body Mass Index (BMI) from your height and weight. BMI is a simple screening number used around the world to classify weight status for adults. It can help you spot trends, set goals, and have more informed conversations with your healthcare provider.
In addition to your BMI score, this calculator also estimates a healthy weight range for your height using standard BMI cutoffs. That makes it useful for people who want a clear target range rather than one single number.
How BMI is calculated
Metric formula
BMI = weight (kg) ÷ [height (m)]²
Imperial formula
BMI = 703 × weight (lbs) ÷ [height (in)]²
This calculator handles both unit systems and does all conversions behind the scenes. If you use imperial units, your feet and inches are combined into total inches before calculation.
BMI categories used in this calculator
- Underweight: BMI below 18.5
- Normal weight: BMI 18.5 to 24.9
- Overweight: BMI 25.0 to 29.9
- Obesity (Class I): BMI 30.0 to 34.9
- Obesity (Class II): BMI 35.0 to 39.9
- Obesity (Class III): BMI 40.0 and above
How to interpret your result
Your BMI is a starting point, not a diagnosis. A single result should be viewed together with other health markers: waist circumference, blood pressure, activity level, sleep quality, family history, and blood test data.
For example, athletes with high muscle mass may show a high BMI without having excess body fat. On the other hand, someone with a “normal” BMI may still have health risks if activity is low and body composition is poor.
Healthy weight range explained
The healthy range shown here is based on BMI 18.5 to 24.9 for your entered height. It is useful for:
- Setting practical weight goals
- Tracking progress in a structured way
- Understanding whether current weight is far from, near, or inside a common target range
Use this range as a guide, not a strict rule. Your ideal weight can vary based on age, body frame, fitness level, and medical context.
Tips for better tracking
1) Measure consistently
Weigh yourself at the same time of day (often morning) and in similar clothing conditions.
2) Track trends, not daily fluctuations
Hydration, sodium intake, sleep, and stress can move scale weight up or down from day to day. Weekly averages are more reliable.
3) Pair BMI with waist and habits
Add waist measurements and lifestyle data (steps, workouts, sleep) to get a much clearer health picture.
Important limitations
- BMI is designed mainly for adult screening and population-level use.
- It does not directly measure body fat percentage.
- It may be less accurate for athletes, older adults, and certain ethnic groups.
- Children and teens should use age- and sex-specific growth charts instead of adult BMI cutoffs.
If your result concerns you, consider discussing it with a healthcare professional who can evaluate your full clinical context.
Quick FAQ
Is BMI enough to define health?
No. It is one indicator. Combine it with nutrition, activity, lab work, and medical guidance.
How often should I recalculate?
Every 2-4 weeks is enough for most people unless a clinician asks for more frequent monitoring.
Can I use this for weight loss planning?
Yes. It is helpful for setting checkpoints, but always prioritize sustainable habits over rapid changes.
Final note
A good calculator gives clarity. A good plan creates results. Use your BMI and healthy weight range as a compass, then build a routine around sleep, movement, strength training, and balanced nutrition.