# Nylon tubing sizes: inch (1/8 to 5/8 in OD) and metric (3 to 12 mm) OD × ID × wall, standard, D.O.T. and high-pressure nylon 11

> What are the OD, ID and wall of 1/4 inch and 6 mm nylon tubing, and which push-in fittings does it fit?

- Category: Tri-clamp & pipe › Pipe, tube & threads
- Kind: Standard part
- Basis: Freelin-Wade nylon tubing datasheet (standard nylon inch and metric, D.O.T. nylon 11, high-pressure nylon 11); one maker; numbers only; pressure ratings left out on purpose
- Page: https://xemstudio.com/objects/nylon-tubing-inch-metric-sizes/ · JSON: https://xemstudio.com/api/geometry?object=nylon-tubing-inch-metric-sizes · Plain text: https://xemstudio.com/objects/nylon-tubing-inch-metric-sizes/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's license
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

**Exact dimensions.** True size, with no tolerance added.

## Notes

- Nylon (polyamide) tubing is sold by OD, with the ID set by the wall: 1/4 in OD comes with three walls, 0.035 in (ID 0.180), 0.040 in (ID 0.170) and 0.062 in (ID 0.125) in the standard line, so '1/4 in nylon tubing' is not one size and the fitting must match the OD. Freelin-Wade's inch sizes are 1/8, 5/32, 3/16, 1/4, 5/16, 3/8, 1/2 and 5/8 in OD; the metric sizes are 3, 4, 5, 6, 8, 10 and 12 mm OD with 1 mm walls from 5 mm up (6 × 4 mm, 8 × 6 mm, 10 × 8 mm, 12 × 10 mm).
- Each maker has its own families: 'standard nylon', 'D.O.T. nylon 11' (air-brake tubing, OD and wall only, no ID printed; the ID shown is OD − 2 × wall) and 'high-pressure nylon 11' (thicker walls, smaller IDs). Millimetres are inch × 25.4; metric inches are mm ÷ 25.4. Each ID and wall was checked against OD − 2 × wall: all agree to within 0.004 in for the inch rows and 0.1 mm for the metric rows.
- Bend radius is shown (inches, as printed) for the standard inch line only; the metric bend radii in the datasheet are printed without units and are not copied. Working pressures at 75 °F and 150 °F, burst pressures and part numbers are left out. One more table in the datasheet (six sizes, 1/8 to 1/2 in, with a lighter pressure rating) has no heading in the text read and is not used; the datasheet also names a 'super soft' nylon 11 with no size table.
- Push-to-connect fittings take tube by OD: push-to-connect-fitting-sizes. Silicone and PU tube: silicone-tube-and-fittings; PTFE: ptfe-fep-pfa-tubing-fractional-sizes; vinyl: tygon-vinyl-tubing-e-3603-sizes; polyethylene: polyethylene-tubing-lldpe-sizes. No files: flexible tubing is not drawn as a fixed shape.

## Sizes

| family | OD as listed | OD, in | OD, mm | ID, in | ID, mm | wall, in | wall, mm | bend radius, in (as printed) |
|---|---|---|---|---|---|---|---|---|
| Standard nylon (inch) | 1/8 | 0.125 | 3.18 | 0.079 | 2.01 | 0.023 | 0.58 | 3/8 |
| Standard nylon (inch) | 1/8 | 0.125 | 3.18 | 0.093 | 2.36 | 0.016 | 0.41 | 1/2 |
| Standard nylon (inch) | 5/32 | 0.1562 | 3.97 | 0.106 | 2.69 | 0.025 | 0.64 | 1/2 |
| Standard nylon (inch) | 3/16 | 0.1875 | 4.76 | 0.138 | 3.51 | 0.025 | 0.64 | 5/8 |
| Standard nylon (inch) | 1/4 | 0.25 | 6.35 | 0.125 | 3.18 | 0.062 | 1.57 | 3/8 |
| Standard nylon (inch) | 1/4 | 0.25 | 6.35 | 0.170 | 4.32 | 0.040 | 1.02 | 3/4 |
| Standard nylon (inch) | 1/4 | 0.25 | 6.35 | 0.180 | 4.57 | 0.035 | 0.89 | 1 |
| Standard nylon (inch) | 5/16 | 0.3125 | 7.94 | 0.232 | 5.89 | 0.040 | 1.02 | 1-1/2 |
| Standard nylon (inch) | 3/8 | 0.375 | 9.53 | 0.275 | 6.99 | 0.050 | 1.27 | 1-1/2 |
| Standard nylon (inch) | 1/2 | 0.5 | 12.70 | 0.375 | 9.53 | 0.062 | 1.57 | 2-1/4 |
| Standard nylon (inch) | 5/8 | 0.625 | 15.88 | 0.500 | 12.70 | 0.062 | 1.57 | 3-1/4 |
| High-pressure nylon 11 (inch) | 1/8 | 0.125 | 3.18 | 0.073 | 1.85 | 0.026 | 0.66 | — |
| High-pressure nylon 11 (inch) | 3/16 | 0.1875 | 4.76 | 0.109 | 2.77 | 0.039 | 0.99 | — |
| High-pressure nylon 11 (inch) | 1/4 | 0.25 | 6.35 | 0.150 | 3.81 | 0.050 | 1.27 | — |
| High-pressure nylon 11 (inch) | 3/8 | 0.375 | 9.53 | 0.225 | 5.72 | 0.075 | 1.91 | — |
| High-pressure nylon 11 (inch) | 1/2 | 0.5 | 12.70 | 0.350 | 8.89 | 0.075 | 1.91 | — |
| D.O.T. nylon 11 (inch; no ID printed) | 1/8 | 0.125 | 3.18 | 0.079 (derived) | 2.01 | 0.023 | 0.58 | — |
| D.O.T. nylon 11 (inch; no ID printed) | 5/32 | 0.1562 | 3.97 | 0.092 (derived) | 2.34 | 0.032 | 0.81 | — |
| D.O.T. nylon 11 (inch; no ID printed) | 3/16 | 0.1875 | 4.76 | 0.116 (derived) | 2.93 | 0.036 | 0.91 | — |
| D.O.T. nylon 11 (inch; no ID printed) | 1/4 | 0.25 | 6.35 | 0.170 (derived) | 4.32 | 0.040 | 1.02 | — |
| D.O.T. nylon 11 (inch; no ID printed) | 5/16 | 0.3125 | 7.94 | 0.232 (derived) | 5.91 | 0.040 | 1.02 | — |
| Standard nylon (metric) | 3 mm | 0.1181 | 3 | 0.071 | 1.8 | 0.024 | 0.6 | — |
| Standard nylon (metric) | 4 mm | 0.1575 | 4 | 0.106 | 2.7 | 0.026 | 0.65 | — |
| Standard nylon (metric) | 5 mm | 0.1969 | 5 | 0.118 | 3 | 0.039 | 1 | — |
| Standard nylon (metric) | 6 mm | 0.2362 | 6 | 0.157 | 4 | 0.039 | 1 | — |
| Standard nylon (metric) | 8 mm | 0.315 | 8 | 0.236 | 6 | 0.039 | 1 | — |
| Standard nylon (metric) | 10 mm | 0.3937 | 10 | 0.315 | 8 | 0.039 | 1 | — |
| Standard nylon (metric) | 12 mm | 0.4724 | 12 | 0.394 | 10 | 0.039 | 1 | — |
| High-pressure nylon 11 (metric) | 5 mm | 0.1969 | 5 | 0.118 | 3 | 0.039 | 1 | — |
| High-pressure nylon 11 (metric) | 6 mm | 0.2362 | 6 | 0.157 | 4 | 0.039 | 1 | — |
| High-pressure nylon 11 (metric) | 8 mm | 0.315 | 8 | 0.236 | 6 | 0.039 | 1 | — |
| High-pressure nylon 11 (metric) | 10 mm | 0.3937 | 10 | 0.315 | 8 | 0.039 | 1 | — |
| High-pressure nylon 11 (metric) | 12 mm | 0.4724 | 12 | 0.394 | 10 | 0.039 | 1 | — |

## Where the files are

- Freelin-Wade: [Nylon tubing: standard nylon (inch and metric), D.O.T. nylon 11, high-pressure nylon 11: OD, ID, wall, bend radius](https://www.freelin-wade.com/documents/Nylon.pdf) — web — Maker datasheet; numbers only

## Questions

**What is the ID of 1/4 inch nylon tubing?**

0.170 in (4.32 mm) with a 0.040 in wall in the standard line; 0.180 in (0.035 in wall) and 0.125 in (0.062 in wall) are also made. High-pressure nylon 11 is 0.150 in ID (0.050 wall).

**What is 6 mm nylon tubing?**

6 mm OD × 4 mm ID (1 mm wall) in both the standard and high-pressure metric lines.

**What is D.O.T. nylon tubing?**

A nylon 11 line with an OD and wall only: 1/4 in is 0.040 in wall (ID derived 0.170 in); 5/32 in is 0.032 in wall.

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