Body Measurement Log
BMI on its own is a thin measure. Tracked alongside a waist measurement and how you actually feel, it becomes useful.
BFCBrilliance · bfcbrilliance.com/tools/bmi-calculator
Your numbers
- Height
- Healthy range from
- Healthy range to
- Starting weight
- Starting BMI
- Starting waist
- Date started
Track it monthly, not daily
| Date | Weight | BMI | Waist | How you feel / notes |
|---|---|---|---|---|
The arithmetic and the bands
- BMI
- weight in kg / (height in m) squared
- 1 pound
- 0.45359237 kg (exact)
- 1 inch
- 2.54 cm (exact)
- Healthy range
- BMI 18.5 to 25 (WHO, adults)
- Under 18.5
- underweight
- 25 to 30
- overweight
- 30 and above
- obese
- Not valid for
- children, teenagers, pregnancy
- Cannot measure
- muscle vs fat, or where fat sits
Measuring it honestly
- Weigh at the same time of day - morning, before eating, is the usual choice
- Same scale every time; move it and re-zero it
- Monthly rather than daily - day-to-day swings are water, not fat
- Waist measured at the navel, tape level, breathing out normally
- Height re-checked once a year - it does change
- A single reading means nothing; the trend across months is the data
- Note anything that would move the number - illness, a new medication, a hard training block
What this number cannot see
BMI knows your weight and your height. It does not know how much of that weight is muscle, where your body stores fat, how fit you are, what you eat, how you sleep, or anything about your blood pressure or blood sugar. Those things matter more to your health than the ratio does, and none of them appear here.
Not medical advice
This is a calculator, not an assessment. BMI was devised in the 1830s to describe populations and was never intended to diagnose an individual. If the number concerns you - in either direction - that is a conversation to have with a doctor who can measure the things this cannot.