Wheelchair Sizing: Seat Width, Depth, Height and Weight Capacity

By Wheelchairs Kenya · Updated June 2026 · Nairobi, Kenya

Why sizing is the difference between comfort and injury

A wheelchair that is too narrow presses on the hips and causes pressure sores at the trochanters. Too wide, and the user leans to one side, strains their shoulders reaching the wheels, and develops back pain. Too deep, and the seat edge cuts circulation behind the knees. Too shallow, and weight concentrates on too small an area. None of these problems announce themselves in the showroom. They show up after weeks of daily use. Five minutes with a tape measure prevents all of them.

The four basic measurements (user seated on a firm surface)

• Seat width: measure across the widest point of the hips/thighs, then add about 5 cm (2″) total clearance. Heavy clothing counts, so measure in normal daily wear. Larger users should look at extra-wide models (we stock an extra-wide foldable at KSh 25,000).
• Seat depth: measure from the back of the buttock to the back of the knee, then subtract about 5 cm so the seat edge does not press the knee crease.
• Seat height / leg length: measure from the heel (with the usual footwear) to the back of the knee. Footrests should support the feet with thighs level. Dangling feet drag, and high knees load the seat bones.
• Backrest height: to mid-shoulder-blade for active self-propellers (frees the arms); higher for users who need trunk support.

Weight capacity: read the label and add a margin

Every wheelchair has a maximum user weight. Exceeding it bends frames, wears bearings and voids warranties. Choose a chair rated at least 20 kg above the user’s weight; for daily all-day use, more margin extends the chair’s life. Heavy-duty models exist for exactly this reason. Ask for one rather than squeezing into a standard frame.

Special cases

Children need growing room: chairs with adjustable width and depth serve a growing child for years; see our CP wheelchair guide for postural sizing. Users with amputations sit further back relative to the wheels; mention it when ordering. And remember the house: the chair’s overall width (wider than the seat) must clear your narrowest doorway. Measure the bathroom door first; it is almost always the narrowest.

Get measured free

Every wheelchair from Wheelchairs Kenya includes free professional fitting: we measure the user at delivery, adjust footrests and backrest, and swap sizes if the fit is wrong. If you are unsure between two sizes, send the four measurements above to us on WhatsApp (0791 371 374) before ordering.