Measure the stem before ordering anything. Pull one caster out and measure the stem’s diameter and length with a ruler or calipers. The usual size is 7/16 by 7/8 in, which is 11 by 22 mm — the Lifelong and OMYOFFICE sets in the chair casters hub both state it — but some chairs use 10 mm stems — the MYNEEED set, sold for IKEA and TOPSTAR chairs, ships both 10 and 11 mm — and a 1 mm difference is the difference between a caster that seats and one that falls out.
Check whether the stem is grip-ring or threaded. A grip-ring stem is a plain pin with a split ring near the top that clicks into the socket; a threaded stem screws in. They are not interchangeable, and a caster with the right wheel and the wrong stem type will not fit the base.
Match the wheel to the floor. Polyurethane or rubber-coated wheels are made for hard floors — wood, tile, laminate — where they roll quietly and do not scratch. Harder nylon wheels suit carpet. Using the wrong kind works, but rolls and grips worse, and a hard wheel on a wood floor is the usual cause of fine scratches.
Read the load figure with care. Sets state ratings from a few hundred to a couple of thousand pounds, and the listings do not all say whether the figure is per wheel or for the set of five. Any of them covers an ordinary chair and user; the figure matters mainly for a heavy-duty chair.
Replace all five at once. The others are usually close behind in wear, and mixing old and new wheels of different heights can leave the chair sitting slightly uneven.
Test on the actual floor. A caster that spins freely in the hand can still drag once the chair and a person are on it. Sit, roll in every direction, and check that the chair stays level.
What buyers ask us first
How do I know if my casters are worn rather than just dirty?
Pull one caster out and look at the wheel tread for flat spots, cracks or a hardened surface, and at the axle for wound-in hair. If clearing the axle does not restore smooth rolling, the wheel is worn.
Are all office chair casters the same size?
No. The 7/16 by 7/8 in (11 by 22 mm) grip-ring stem is the most common — it is the size most sets in this site's caster hub state — but some chairs use a 10 mm stem or a threaded one. Measuring the old stem is what prevents a wrong order.
How do I get the old casters out?
Most grip-ring casters are a push fit: turn the chair over, grip the wheel and pull firmly, rocking it slightly. A flat lever between the wheel housing and the base helps with a stiff one. New ones push in until the ring clicks past the socket lip.
Should I replace the base instead?
Only if the base itself is cracked or the sockets are worn loose. Replacement bases in the caster hub run from about $40 to $66; a set of casters starts around $8 to $15.
Last reviewed 13 October 2026