255/70R16 tire size in inches
A 255/70R16 tire is 30.06 inches tall and 10.04 inches wide on a 16-inch rim. These are nominal dimensions from the official sizing formula.
| Dimension | 255/70R16 | This size vs yours | |
|---|---|---|---|
| Overall diameter UN R30 §6.1.2.1 | 30.06 in 763.4 mm | ||
| Section width UN R30 §6.1.2.1 | 10.04 in 255.0 mm | ||
| Sidewall height UN R30 §6.1.2.1 | 7.03 in 178.5 mm | ||
| Rim diameter Marked on the tire | 16 in | ||
| Circumference From diameter | 94.42 in | ||
| Revolutions per mile From diameter | 671 | ||
| Allowed real diameter UN R30 §6.1.5 | 29.63–30.62 in |
Is 255/70R16 a 30-inch tire?
Yes. At 30.06 inches tall, 255/70R16 is commonly called a 30-inch tire. Inch-class names round to the nearest inch; the true nominal height is 30.06 in, and a new tire may legally measure between 29.63 and 30.62 in.
Speedometer change
Example: if your speedometer is calibrated for 245/75R16 and you fit 255/70R16, the tire is −1.4% in diameter, so your true speed differs from the reading as shown below. Enter your current size above to see your own figures.
| Reading | True speed | Difference |
|---|---|---|
| 30 mph | 29.6 mph | −0.4 mph |
| 45 mph | 44.4 mph | −0.6 mph |
| 55 mph | 54.3 mph | −0.7 mph |
| 60 mph | 59.2 mph | −0.8 mph |
| 70 mph | 69.1 mph | −0.9 mph |
| 80 mph | 78.9 mph | −1.1 mph |
Sizes within 3% of 255/70R16
These sizes are within 3% of the diameter of 255/70R16. The 3% figure is a rule of thumb, not a regulation and not a fitment check: wheel width, offset, suspension and body clearance decide what fits. See changing tire size.
| Size | Diameter (in) | Width (in) | Change | ±3% | Ride height (in) |
|---|---|---|---|---|---|
| 225/75R16 | 29.29 | 8.86 | −2.6% | −0.38 | |
| 245/65R17 | 29.54 | 9.65 | −1.7% | −0.26 | |
| 255/70R16 | 30.06 | 10.04 | — | — | |
| 265/50R20 | 30.43 | 10.43 | +1.3% | +0.19 | |
| 245/75R16 | 30.47 | 9.65 | +1.4% | +0.21 | |
| 245/70R17 | 30.50 | 9.65 | +1.5% | +0.22 | |
| 265/60R18 | 30.52 | 10.43 | +1.5% | +0.23 | |
| 265/65R17 | 30.56 | 10.43 | +1.7% | +0.25 | |
| 265/70R16 | 30.61 | 10.43 | +1.8% | +0.28 | |
| 265/75R15 | 30.65 | 10.43 | +2.0% | +0.30 |
Inch equivalent of 255/70R16
In inch terms, 255/70R16 is about 30.1x10.0R16: 30.1 in tall and 10.0 in wide, a 30-inch tire.
| Inch size | Diameter (in) | Change | Width (in) | Dimensions from |
|---|---|---|---|---|
| 31x10.50R15 | 30.51 | +1.5% | 10.55 | UN R54 table |
| 31x11.50R15 | 30.51 | +1.5% | 11.42 | UN R54 table |
| 31x13.50R15 | 30.51 | +1.5% | 13.58 | UN R54 table |
How 255/70R16 is calculated
255 mm section width × 70% aspect ratio = 178.5 mm sidewall (7.03 in).
Overall diameter = rim + 2 × sidewall = 16 in + 2 × 7.03 in = 30.06 in.
Formula: UN Regulation No. 30 §2.15 and §6.1.2.1 (passenger) and UN Regulation No. 54 §6.1.2.1 (light truck). Revolutions per mile = 63,360 ÷ circumference. Full sources are listed at the end of this page.
Questions about 255/70R16
- How tall is a 255/70R16 tire?
- 30.06 inches (763.4 mm) nominal. A new tire may measure from 29.63 to 30.62 in under the official tolerance; the maker's specification gives the figure for a specific tire.
- How wide is a 255/70R16 tire?
- 10.04 inches (255.0 mm) section width. Overall width can be slightly larger; for passenger tires, US rule FMVSS 139 allows 7% over the specified width (or 10 mm, if larger, for some pressure classes).
- How many revolutions per mile does 255/70R16 make?
- About 671 nominal, from a circumference of 94.42 in. Tire makers publish measured revolutions per mile for each tire.
- Will 255/70R16 fit my vehicle?
- This page can't tell you. Check the tire size on your door-jamb placard, then confirm wheel width, offset and clearance with the tire or vehicle maker.
Related
Printed from https://tiresizecalc.net/size/255-70r16/. Figures as published on 2026-11-01. The full working and the official sources are on that page.
Sources
This size is listed by the manufacturer: Goodyear Wrangler Workhorse AT 2, checked on the manufacturer's site on 2026-11-01. The size page shows nominal figures, not that product's measurements.
- 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.
- 49 CFR 571.110 - Standard No. 110; Tire selection and rims for motor vehicles with a GVWR of 4,536 kilograms (10,000 pounds) or less. National Highway Traffic Safety Administration (NHTSA), Code of Federal Regulations, annual edition (GovInfo). 2006-10-01. S4.3: the door placard shows the original tire size. 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.