[header] How to measure a wheelchair [title] Measure the width of the person who will use the wheelchair. [step] Take the measurement with the person in the seated position, on a fairly firm surface. This will determine the width of the seat. 
[substeps] Add approximately 1 to 2 inches (2.5 to 5 cm) for slight movement and comfort when sitting. Allow for the thickness of bulky clothing, which could be worn in the winter.