Tool · Measuring and buying
Upright size finder
Pick the upright size you measured to see the other unit, the near-miss size it is confused with, the hole and pin sizes makers list, and the racks that use it.
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Short answer
Pick the upright size you measured to see the same size in the other unit, the near-miss size it is often confused with, the hole and pin sizes makers list for it, and the rack systems that use it. The converted figures are arithmetic, not a sign that a part made for one size fits the other.
Picks this tool points toAll best picks
- 2x2 in uprights
- 2x3 in uprights
- 3x3 in uprights
- 60 mm uprights
- 75 mm uprights
Choose your upright size to see the key facts and what fits. Each fact links to its source on the full page.
The sizes at a glance
| Upright size | Nominal size | Calculated other unit | Often confused with | Pin sizes makers list |
|---|---|---|---|---|
| 2x2 in uprights | 2 x 2 in | 50.8 x 50.8 mm (calculated from 25.4 mm per inch) | 50 x 50 mm metric tubing | REP 1000 Series standard J-cups: 1 in pins |
| 2x3 in uprights | 2 x 3 in | 50.8 x 76.2 mm (calculated from 25.4 mm per inch) | 2x2 in and 3x3 in tubing, which each share one face width with 2x3 | Rogue Infinity J-cups: 5/8 in. Titan T-3 J-hooks (JHOOK_T3): 5/8 in. Titan T-3 strap spotter arms: two hitch pins per arm. |
| 3x3 in uprights | 3 x 3 in | 76.2 x 76.2 mm (calculated from 25.4 mm per inch) | 75 x 75 mm tubing: 3x3 in is 1.2 mm larger per side by label | 5/8 in hardware: Rogue RML-690 and SML-2, REP PR-4000. 1 in hardware: Rogue RM-6, REP PR-5000. Parts: REP Round Sandwich J-cups 5/8 in; Rogue Ghost Roller J-Cups 2.0 in 5/8 in and 1 in versions. |
| 60 mm uprights | 60 x 60 mm, sold as 2.3 in (Bells of Steel) or 2.4 in (Force USA) | About 2.362 in (calculated from 25.4 mm per inch) | The 2.3 in and 2.4 in labels for the same 60 mm size; Powertec's 2 3/8 in uprights, which calculate to 60.325 mm | Not confirmed |
| 75 mm uprights | 75 x 75 mm | About 2.953 in (calculated from 25.4 mm per inch) | 3 x 3 in (76.2 mm): 1.2 mm larger per side by label | Not confirmed |
Conversions are calculations, not tolerances
Every converted figure starts from one fact: an inch is defined as exactly 25.4 mm.[1] From that, a 2x2 in upright works out to 50.8 x 50.8 mm, which is not the same size as a 50 x 50 mm metric tube.[1] A 3x3 in upright works out to 76.2 x 76.2 mm, 1.2 mm larger per side than a 75 x 75 mm tube.[1] A 60 mm tube is about 2.362 in, which makers round to different labels such as 2.3 in or 2.4 in.[1]
These numbers say nothing about how much play an attachment allows. No maker we read publishes a tolerance, so a near-miss size is a reason to check the attachment maker's list, not a reason to buy.
One maker, two tube sizes
Bells of Steel says every one of its racks uses either 2.3 x 2.3 in (60 x 60 mm) or 3 x 3 in (76.2 x 76.2 mm) square tubing.[2] Force USA lists its MyRack uprights as 2.4 in square (60 mm).[3] So "60 mm" can carry either label, and the label alone does not tell you whether another brand's part fits.
From size to rack
Each size page links to the rack systems that use it. Once you know your rack line, the rack attachment fit finder shows its hole diameter, hardware size and spacing, plus the attachments its maker lists.
Next
- How to measure your rack's uprights, holes and spacing
- 2x2 vs 50 mm, 3x3 vs 75 mm and 60 mm rack tubing
- Rack attachment fit finder: pick your rack system
- 2x2 in uprights
- 2x3 in uprights
- 3x3 in uprights
- 60 mm uprights
- 75 mm uprights
Choose your upright size to see the key facts and what fits. Each fact links to its source on the full page.
Shop what this tool points toAll best picks
Questions
Will a 75 mm attachment fit my 3x3 rack?
Do not assume so. A 3x3 in upright works out to 76.2 mm, 1.2 mm larger per side than 75 mm. Fit depends on the attachment maker's list, not on a converted number.[1]
Is a 2.3 in rack the same as a 2.4 in rack?
Both labels are used for 60 mm tubing: Bells of Steel labels its 60 mm tubing 2.3 in and Force USA labels MyRack 2.4 in. A shared metric size does not establish cross-brand fit.[2][3]
My measurement is between two sizes. What does that mean?
Paint and coatings add thickness, and no maker we read publishes tolerances. Measure again, then compare with your rack maker's stated size; if it still does not match, ask the maker.