Hydraulic hose sizes can be confusing to many people, especially if you do not work with the sizing on a frequent basis. We have put together the chart below to help guide you on hydraulic hose sizes, but keep in mind, that the info below does not apply to some hydraulic hoses on the market. The ones it does not apply to is a very small segment though. In the United States, the most common hydraulic hose size is -6 (3/8″) and -8 (1/2″) hydraulic hose. If you are unsure of the ID of your existing hydraulic hose, check the lay line. The lay line is the “ribbon” of information molded into or printed on the cover of your hydraulic hose.
| Dash No. | Inches | Millimeters |
|---|---|---|
| -2 | 1/8 | 3.2 |
| -3 | 3/16 | 4.8 |
| -4 | 1/4 | 6.4 |
| -5 | 5/16 | 7.9 |
| -6 | 3/8 | 9.5 |
| -8 | 1/2 | 12.7 |
| -10 | 5/8 | 15.9 |
| -12 | 3/4 | 19.0 |
| -14 | 7/8 | 22.2 |
| -16 | 1 | 25.4 |
| -20 | 1 1/4 | 31.8 |
| -24 | 1 1/2 | 38.1 |
| -32 | 2 | 50.8 |
| -36 | 2 1/4 | 57.6 |
| -40 | 2 1/2 | 63.5 |
| -48 | 3 | 76.2 |
| -56 | 3 1/2 | 88.9 |
| -64 | 4 | 101.6 |
| -72 | 4 1/2 | 115.2 |