BMI Calculator
Calculate body mass index from height and weight, switch between supported units, and review the standard BMI range shown for the result.
BMI Calculator
Ideal Weight Calculator
Use the scientific calculator with steps
The formula, worked through
BMI = weight(kg) ÷ height(m)²
- For 70 kg at 1.75 m, square the height: 1.75 × 1.75 = 3.0625.
- Divide: 70 ÷ 3.0625 = 22.86.
- A BMI of 22.9 falls inside the 18.5–24.9 "healthy weight" band.
- In imperial units use 703 × lb ÷ in²: 154 lb at 69 in also gives 22.8.
- Weight
- 70 kg
- Height
- 1.75 m
Result BMI 22.86 — healthy range
When to use this calculator
- Check a general reference value Enter consistent height and weight units, then use the BMI value as a general reference rather than a diagnosis.
- Review the limitation BMI does not account for every factor affecting health or body composition. Discuss personal health decisions with a qualified professional.
- What moves the bmi number The bmi result is only as good as the inputs: change one field at a time and watch which figures shift before you commit to a decision.
Estimate body mass index
Enter height and weight in one consistent unit system. BMI is a screening measure based on height and weight, not a diagnosis and not a complete measure of health. The result should be interpreted with age, muscle mass, medical context, and professional guidance.
Formula
Metric BMI equals weight in kilograms divided by height in meters squared. Imperial inputs use the corresponding conversion factor before applying the same relationship.
Worked example
A person who weighs 70 kilograms and is 1.75 meters tall has a BMI near 22.9. Use the result as a screening estimate and check the category guidance relevant to the person and context.
Frequently Asked Questions about BMI Calculator
Is BMI a medical diagnosis?
No. BMI is a screening measure based on height and weight and does not diagnose health conditions or describe individual body composition.
Can I use pounds and feet?
Use the unit controls provided by the calculator and make sure the height and weight values match the selected units before calculating.
How do I sanity-check the bmi result?
Rerun the calculator with a known example and compare it against the figure you expect; then swap back to your own numbers.
Which bmi inputs change the outcome most?
Adjust one field at a time. The figure that shifts the result hardest is the assumption worth double-checking before you rely on it.
What is the BMI for 70 kg and 175 cm?
22.86, which is in the healthy-weight range of 18.5 to 24.9.
At what BMI am I considered overweight?
By standard WHO categories, BMI 25.0–29.9 is overweight and 30.0+ is obesity. For 1.75 m tall that threshold is about 76.6 kg.