Hitch ball sizes
The ball size is decided by your coupler, not by your trailer weight. Check the stamp on the coupler — 1-7/8 in, 2 in or 2-5/16 in — and match it exactly. Then check that the ball's capacity also covers your loaded trailer weight.
| Ball diameter | Shank diameter | Gross trailer weight | |
|---|---|---|---|
| 1-7/8 in | 3/4 in to 1 in | 2,000–3,500 lb | Find →Affiliate link — as an Amazon Associate we earn from qualifying purchases, at no extra cost to you. |
| 2 in | 3/4 in to 1-1/4 in | 3,500–12,000 lb | Find →Affiliate link — as an Amazon Associate we earn from qualifying purchases, at no extra cost to you. |
| 2-5/16 in | 1 in to 2 in | 6,000–30,000 lb | Find →Affiliate link — as an Amazon Associate we earn from qualifying purchases, at no extra cost to you. |
| 3 in | 2 in | 30,000 lb | Find →Affiliate link — as an Amazon Associate we earn from qualifying purchases, at no extra cost to you. |
Ball diameter MUST match the coupler size stamped on your trailer coupler. An undersized ball lets the trailer bounce loose. Capacity varies by part number.
Common questions
What size hitch ball do I need?
Whatever size is stamped on your trailer's coupler — 1-7/8 in, 2 in or 2-5/16 in. The weight does not choose the ball; the coupler does. An undersized ball can let the trailer bounce off the hitch.
Can I use a 2 inch ball on a 2-5/16 inch coupler?
No. It creates excessive play and can cause the trailer to sway or come off entirely. The diameters must match exactly.
Source: CURT Manufacturing — Standard Trailer Hitch Ball Sizes · last verified 2026-08-29