285 mm tire sizes
A 285 mm wide tire is 11.22 inches wide (nominal section width). This site lists 9 sizes with a 285 width, from 32.34 to 34.83 inches tall.
285 mm ÷ 25.4 = 11.22 in. The first number in a metric size is the section width in millimetres. A real tire can be slightly wider. For passenger tires, FMVSS No. 139 permits up to 7 percent over the specified width.
Height of each 285 size, in inches
Each row is an aspect ratio and each column a rim diameter. Select a height to open that size.
| Size | 16 in | 17 in | 18 in | 20 in |
|---|---|---|---|---|
| 285/55 | – | – | – | 32.34 |
| 285/60 | – | – | – | 33.46 |
| 285/65 | – | – | 32.59 | 34.59 |
| 285/70 | – | 32.71 | 33.71 | – |
| 285/75 | 32.83 | 33.83 | 34.83 | – |
285 mm compared with the next widths
A change of 10 mm in section width moves each sidewall about 5 mm (0.20 in), if the wheel offset stays the same.
To see where the sidewalls go on your wheel, use the wheel offset calculator. To keep the diameter on a different rim, use the plus-size calculator.
285 sizes by inch class
- 32-inch (all 32-inch sizes): 285/55R20
- 33-inch (all 33-inch sizes): 285/65R18, 285/70R17, 285/75R16, 285/60R20
- 34-inch (all 34-inch sizes): 285/70R18, 285/75R17
- 35-inch (all 35-inch sizes): 285/65R20, 285/75R18
Inch-class names round the nominal diameter to the nearest inch. See inch tire sizes.
Printed from https://tiresizecalc.net/width/285-tires/. Figures as published on 2026-11-01. The sources are listed below.
Sources
- UN Regulation No. 30 - Uniform provisions concerning the approval of pneumatic tyres for motor vehicles and their trailers (Revision 3). United Nations Economic Commission for Europe (UNECE). E/ECE/324 E/ECE/TRANS/505 Rev.1/Add.29/Rev.3. 2007-03-29. Para 2.15 and 6.1.2.1: aspect ratio and outer diameter, D = d + 2H. Retrieved 2026-11-01.
- UN Regulation No. 54 - Uniform provisions concerning the approval of pneumatic tyres for commercial vehicles and their trailers (Revision 2). United Nations Economic Commission for Europe (UNECE). E/ECE/324 E/ECE/TRANS/505 Rev.1/Add.53/Rev.2. 2004-04-16. Para 6.1.2.1: the same formula for light truck tires. Retrieved 2026-11-01.
- UN Regulation No. 30 - Uniform provisions concerning the approval of pneumatic tyres for motor vehicles and their trailers (Revision 3). United Nations Economic Commission for Europe (UNECE). E/ECE/324 E/ECE/TRANS/505 Rev.1/Add.29/Rev.3. 2007-03-29. Para 6.1.5: allowed outer diameter, Dmin = d + 2H x 0.97, Dmax = d + 2H x 1.04. Retrieved 2026-11-01.
- Computed by tiresizecalc.net from the cited formula. Sri Murugan Systems. Circumference = pi x diameter; revolutions per mile = 63,360 / circumference; 1 in = 25.4 mm exactly. Retrieved 2026-11-01.
- 49 CFR 571.139 - Standard No. 139; New pneumatic radial tires for light vehicles. National Highway Traffic Safety Administration (NHTSA), Code of Federal Regulations (eCFR). 49 CFR 571.139. eCFR up to date as of 2026-10-15. S6.1.2: passenger tire width up to 7 percent (or 10 mm) over the specified width. Retrieved 2026-11-01.
- Computed by tiresizecalc.net from the cited formula. Sri Murugan Systems. Inches = mm / 25.4; each sidewall moves half of the width change when the offset stays the same. Retrieved 2026-11-01.
Last reviewed 2026-11-01. The full source list, with dates and file checksums, is in How the numbers are calculated. To report an error, email contactus@tiresizecalc.net.