Caster Size Chart: Dimensions by Type & Application
Choosing the right caster size, wheel diameter, wheel width, and overall height, affects load capacity, rolling resistance, floor clearance, and compatibility with your equipment. This reference chart covers standard caster sizes by application type.
How Caster Dimensions Are Measured: Wheel diameter is the distance across the wheel at the tread (affects load capacity, rolling resistance, obstacle clearance). Wheel width (tread width) is the side-to-side width of the contact surface (affects floor pressure, stability). Overall height is the bottom of wheel to top of mounting plate (affects cart deck height, clearance). Plate dimensions are the length x width of the top plate (bolt pattern compatibility). Bolt hole pattern is the diagonal or adjacent spacing between bolt holes (direct replacement compatibility).
Standard Wheel Diameter Guide
Load ranges vary by wheel material, rig type, and bearing. See product specifications for exact ratings.
| Wheel Diameter | Typical Load Range | Common Applications |
|---|---|---|
| 2" | 75-150 lbs/caster | Small carts, light furniture, instrument stands |
| 3" | 100-300 lbs/caster | Light-duty utility carts, medical equipment, display fixtures |
| 4" | 200-600 lbs/caster | Hospital carts, retail fixtures, medium utility carts, tool carts |
| 5" | 300-900 lbs/caster | Industrial carts, warehouse utility carts, assembly carts |
| 6" | 400-1,200 lbs/caster | Heavy industrial, platform carts, heavy assembly equipment |
| 8" | 500-1,400 lbs/caster | Very heavy industrial, dock carts, heavy-duty platform equipment |
| 10"+ | 1,000+ lbs/caster | Extra-heavy industrial, outdoor equipment, large platform trucks |
Standard Plate Mount Bolt Patterns
Measure diagonally between opposite bolt holes for the most reliable pattern identification. Most industrial casters use 3/8" bolts.
| Pattern (Adjacent) | Pattern (Diagonal) | Common Usage |
|---|---|---|
| 1-3/4" x 2-3/4" | ~3-1/4" diagonal | Light-to-medium duty, smaller carts |
| 2" x 3" | ~3-5/8" diagonal | Medium duty utility carts |
| 2-1/4" x 3-1/4" | ~3-15/16" diagonal | Standard industrial (most common) |
| 2-3/8" x 3-5/8" | ~4-3/8" diagonal | Standard industrial (most common) |
| 3" x 3" | ~4-1/4" diagonal | Square pattern, some heavy industrial |
| 3" x 4-1/2" | ~5-7/16" diagonal | Heavy-duty industrial, large plate casters |
| 4" x 4-1/2" | ~6" diagonal | Very heavy-duty, specialized industrial |
Grip Ring Stem Sizes (Office Chairs)
| Stem Size | Fits Socket Diameter | Common Application |
|---|---|---|
| 7/16" x 7/8" | 7/16" ID socket | Standard office chairs (most common, 95%+) |
| 5/16" x 7/8" | 5/16" ID socket | Lighter chairs, some European models |
| 3/8" x 1" | 3/8" ID socket | Some heavy-duty office chairs |
Overall Height by Wheel Size
Typical ranges for plate mount swivel casters. Rigid casters have slightly lower overall height.
| Wheel Diameter | Typical Overall Height Range |
|---|---|
| 2" | 2-3/4" - 3-1/4" |
| 3" | 3-3/4" - 4-1/4" |
| 4" | 4-3/4" - 5-1/2" |
| 5" | 5-3/4" - 6-1/2" |
| 6" | 6-3/4" - 7-3/4" |
| 8" | 8-1/2" - 10" |
How to Use This Reference
Caster Sizing by Application Type
Office Chairs: 2" (standard) or 2.5"-3" (rollerblade/upgraded) wheel diameter. 7/16" x 7/8" grip ring stem (95%+ of chairs). 3/4"-1" wheel width.
Medical / Hospital Carts: 4"-6" wheel diameter for smooth hospital floor transitions. Plate mount (3" x 3" or 2-3/8" x 3-5/8" common). Non-marking polyurethane, sealed bearings.
Warehouse Utility Carts: 5"-6" wheel diameter. Plate mount (2-3/8" x 3-5/8" most common). 1-1/4"-2" wheel width. Capacity target: 600-1,200 lbs per cart = 150-300 lbs per caster x 1.25 safety factor.
Industrial / Manufacturing Carts: 5"-8" depending on load. Plate mount (2-3/8" x 3-5/8" or larger). Kingpinless rig for loads over 800 lbs/caster. Size to application load x 1.5 safety factor.
Food Service / Commercial Kitchen: 4"-5" wheel diameter. Plate mount with stainless hardware. NSF polyurethane or stainless steel wheel. NSF/ANSI 2 listed.
Platform / Dock Carts: 6"-10" wheel diameter (larger for dock transitions). Heavy plate mount. Polyurethane or pneumatic for dock transitions. Very high capacity, calculate per application.
Common Replacement Scenarios & Specs
The replacement casters have a larger overall height. You need casters with smaller wheel diameter or a lower-profile swivel rig. Measure the original caster's overall height and match it exactly for replacement.
Measure the bolt pattern on your original casters and the replacement, compare diagonal measurements. You may need an adapter plate or a different caster model. Contact our team with both measurements for a recommendation.
The grip ring stem is not seating properly in the socket. This usually means the socket is worn and oversize. Try a grip ring stem one size up or use a threaded stem with a socket insert.
5/16"-18: Light furniture, some US chairs
3/8"-16: Medium-duty furniture, US carts
M10 x 1.5: European furniture (metric)
M12 x 1.75: Heavier European applications
Need Help with Your Caster Order?
Visit the resources linked below including everything you need to get you started!