How to Read a Caster Spec Sheet
A caster spec sheet packs a lot into a few lines. Reading it correctly is the difference between a lot that fits your equipment and one that does not. Here are the specs that matter and how to use them.
The specs that decide fit
| Spec | What to check |
|---|---|
| Load capacity | Rating per caster. Confirm whether it is per caster or per set, and whether it is a dynamic (rolling) or static rating. |
| Wheel diameter | Larger wheels roll easier over obstacles and raise capacity, but increase overall height. |
| Wheel / tread material | Polyurethane, rubber, phenolic, steel, nylon, or thermoplastic. Drives floor protection, roll resistance, and chemical tolerance. |
| Mount type | Top plate (with bolt-hole pattern) or stem (threaded, grip-ring, expanding). Must match your equipment. |
| Swivel vs rigid | Swivel rotates 360 degrees; rigid runs straight. Most carts use two of each. |
| Bearing type | Precision, roller, or plain. Affects roll effort and load behavior. |
| Overall height & swivel radius | Determines deck height and how much clearance the caster sweeps. |
Sizing capacity for your load
A common rule: take the total load (equipment plus payload), divide by the number of casters minus one to allow for uneven floors, then add a safety margin. For a 2,000 lb load on four casters: 2,000 / 3 = 667 lb per caster minimum, so a 1,000 lb-rated caster gives comfortable headroom.
Match by capacity, size, and material
Once you know your numbers, shop by the spec that matters most. Browse by load capacity, by wheel size, or by caster type such as swivel and plate.