BMI Prime
If BMI 25 is the overweight threshold, dividing BMI by 25 puts the line at exactly one. 0.92 means 92% of the way there; 1.15 means 15% past it — no need to remember the cut-offs.
Your numbers
BMI Prime
1.001
BMI
25
Difference
0kg
What it means
1.001 is 0% past the overweight threshold.
Formula
BMI Prime = BMI ÷ 25
The 25 cut-off is the WHO international standard. Asia-Pacific guidance treats 23 as overweight, so divide by 23 to read it that way.
What to enter
| Input | Default | Accepted range |
|---|---|---|
| Weight (kg) (kg)The second weight you are comparing against. | 74 | 1 and up |
| Height (cm) (cm)Height in centimetres; converted to metres inside the formula. | 172 | 50 and up |
Step by step
Quick reference table
Results when only Weight (kg) (kg) changes and everything else stays put.
| Weight (kg) (kg) | BMI Prime | BMI | Difference (kg) |
|---|---|---|---|
| 37 | 0.5 | 12.5 | -37 |
| 55.5 | 0.75 | 18.8 | -18.5 |
| 74 | 1.001 | 25 | 0 |
| 111 | 1.501 | 37.5 | 37 |
| 148 | 2.001 | 50 | 74 |
What each result means
| Result | At default values |
|---|---|
| BMI PrimeBMI divided by the overweight cut-off; one is the line. | 1.001 |
| BMIA build index from height and weight alone; it cannot tell muscle from fat. | 25 |
| Difference (kg)The gap between two values — a quantity, not a rate. | 0 |
Common mistakes
The 25 cut-off is the WHO international standard. Asia-Pacific guidance treats 23 as overweight, so divide by 23 to read it that way.
Glossary
- Weight (kg)
- The second weight you are comparing against.
- Height (cm)
- Height in centimetres; converted to metres inside the formula.
- BMI Prime
- BMI divided by the overweight cut-off; one is the line.
- BMI
- A build index from height and weight alone; it cannot tell muscle from fat.
- Difference
- The gap between two values — a quantity, not a rate.
Frequently asked questions
Q. How is BMI Prime calculated?
BMI Prime = BMI ÷ 25 — If BMI 25 is the overweight threshold, dividing BMI by 25 puts the line at exactly one. 0.92 means 92% of the way there; 1.15 means 15% past it — no need to remember the cut-offs.
Q. Can you walk through an example?
With Weight (kg) 74kg, Height (cm) 172cm, the answer is BMI Prime 1.001.
Q. What do I need to enter?
Enter Weight (kg), Height (cm). The result recalculates as you type, and an empty box counts as zero.
Q. How much does the answer move if I change a number?
Changing only Weight (kg) (kg) moves the answer to Weight (kg) (kg) 37 → BMI Prime 0.5 and Weight (kg) (kg) 148 → BMI Prime 2.001. The table below lays out five steps.
Q. How are the numbers rounded?
Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.
Q. Anything to watch out for?
The 25 cut-off is the WHO international standard. Asia-Pacific guidance treats 23 as overweight, so divide by 23 to read it that way.
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These calculators help you understand health figures; they do not replace diagnosis or prescription. See a clinician if you have symptoms.