How to measure height, weight and BMI
Other platforms explain it with text and video. In Making Synapses you practice it on the patient.
Weight changes guide drug doses, fluid balance and nutrition. Measuring the same way each time is what makes it useful.
What you need
- Calibrated scale
- Stadiometer
- Measuring tape
Step by step
Prepare
Explain, ask the patient to remove shoes and heavy clothes, and to empty the bladder if weight is tracked daily. [1]
Weight
Zero the scale, patient stands still in the center. Same scale, same time of day and similar clothing for follow-up weights. [1]
Height
Heels together, back of heels, buttocks, shoulders and head against the stadiometer, looking straight ahead. Lower the headpiece to the top of the head. [1]
BMI
Weight in kilograms divided by height in meters squared. [1]
Waist circumference when asked
Tape around the waist at the top of the hip bones, snug but not tight, at the end of a normal breath out. [1]
Record
Write values with units and compare with the last ones. Report a quick gain (fluid) or loss. [1]
Common errors
- Not zeroing the scale.
- Measuring height with shoes on.
- Mixing pounds and kilograms in the record.
Adult BMI categories [1]
| Category | BMI (kg/m²) | |
|---|---|---|
| Underweight | under 18.5 | |
| Healthy weight | 18.5 to 24.9 | |
| Overweight | 25 to 29.9 | |
| Obesity | 30 or higher |
Practice it in Making Synapses
In Making Synapses you do this on the patient, not on paper: every step goes on the checklist with a score, and in Teach mode Blocky tells you what comes next.
Making Synapses cases that train this skill
- Gestational diabetes
- Liver failure with hepatic encephalopathy
- Obesity
- Tuberculosis, contact with symptoms
- ADHD with weight loss
- Neonatal jaundice
46 Making Synapses cases train this skill: open the case library
Sources
Facts and steps follow OpenStax, Clinical Nursing Skills (reference). Making Synapses is not affiliated with these organizations. Updated: 2026-10-11.