285/75R16 vs 265/70R17
265/70R17 is −1.22″ in overall diameter and −20 mm in section width against 285/75R16 — a diameter change of −3.73%, which sits outside the commonly used ±3% diameter guide. An indicated 60 mph would really be 57.8 mph.
Opens the calculator prefilled. The pair stays in the link fragment, not an account or server log.
Every dimension
| Dimension | 285/75R16 → 265/70R17 | Change |
|---|---|---|
| Overall diameter | 32.83″ → 31.61″ | −1.22″ (−3.73%) |
| Section width | 285 mm → 265 mm | −20 mm (−7.02%) |
| Sidewall height | 213.8 mm → 185.5 mm | −28.3 mm |
| Rolling circumference | 103.14″ → 99.29″ | −3.85″ |
| Revolutions per mile | 614.3 → 638.1 | +23.8 |
| Axle height / clearance | 16.42″ → 15.80″ | −0.61″ |
Which is taller, 285/75R16 or 265/70R17?
285/75R16 is the taller of the two, at 32.83″ against 31.61″. The gap is 1.22 inches, or 31.1 mm.
Both are metric sizes, so neither states its height directly. Both figures below are derived from the section width, aspect ratio and wheel diameter in the code. 285/75R16 is 285 mm wide with a 213.8 mm sidewall on a 16″ wheel; 265/70R17 is 265 mm wide with a 185.5 mm sidewall on a 17″ wheel.
What the speedometer will read
| Speedometer reads | Actual speed | Error |
|---|---|---|
| 25 mph | 24.1 mph | −0.9 mph |
| 40 mph | 38.5 mph | −1.5 mph |
| 55 mph | 52.9 mph | −2.1 mph |
| 60 mph | 57.8 mph | −2.2 mph |
| 70 mph | 67.4 mph | −2.6 mph |
| 80 mph | 77.0 mph | −3.0 mph |
Fitting 265/70R17 in place of 285/75R16 multiplies every speed and distance reading by 0.96271. Over 10,000 indicated miles the odometer is out by −373 miles.
Effective gearing moves by the same proportion. A vehicle with 3.73 axles running 285/75R16 would need 3.59 to keep the same engine speed on 265/70R17. Work it out for your own axle ratio.
Full specification of each size
285/75R16
| Dimension | Metric | Imperial |
|---|---|---|
| Section width | 285.0 mm | 11.22″ |
| Sidewall height | 213.8 mm | 8.42″ |
| Wheel diameter | 406.4 mm | 16.0″ |
| Overall diameter | 833.9 mm | 32.83″ |
| Rolling circumference | 2,619.8 mm | 103.14″ |
| Revolutions per mile | 381.7 / km | 614.3 / mile |
| Measuring rim (estimate) | 203 mm | 8″ |
265/70R17
| Dimension | Metric | Imperial |
|---|---|---|
| Section width | 265.0 mm | 10.43″ |
| Sidewall height | 185.5 mm | 7.30″ |
| Wheel diameter | 431.8 mm | 17.0″ |
| Overall diameter | 802.8 mm | 31.61″ |
| Rolling circumference | 2,522.1 mm | 99.29″ |
| Revolutions per mile | 396.5 / km | 638.1 / mile |
| Measuring rim (estimate) | 203 mm | 8″ |
Rim widths differ too: 285/75R16 is designed for 7.5″–9″ and 265/70R17 for 7.5″–9″. Their estimated measuring rim is the same; confirm the exact tire maker's approved range before mounting either one.
Can you swap one for the other?
Outside the ±3% diameter guide
The diameter difference of −3.73% exceeds the commonly used ±3% geometry guideline. Expect a speedometer error of about 2.2 mph at an indicated 60, and an odometer that is off by the same proportion. Confirm instrument, clearance and vehicle-system implications with qualified sources before using it.
Neither figure says anything about physical fitment. Whether 265/70R17 clears the strut, the fender liner and the steering stops depends on wheel offset and suspension geometry that a size code does not encode. For maintenance rather than sizing, Car Basics covers tire care.
285/75R16 vs 265/70R17: common questions
- Is 265/70R17 bigger than 285/75R16?
- 265/70R17 is 1.22 inches shorter and 20 mm narrower. In overall diameter that is −3.73%, which exceeds the commonly used ±3% diameter guideline.
- How much will 265/70R17 throw off my speedometer?
- Every reading scales by 0.96271. An indicated 60 mph becomes 57.8 mph, and every 100 miles on the odometer is really 96.3 miles.
- How much does 265/70R17 change ground clearance over 285/75R16?
- The axle centerline moves by 0.61 inches — half the diameter change, because half the extra height sits below the hub and half above it.
- Will 265/70R17 fit where 285/75R16 fits?
- Nothing derived from the size code can answer that. Clearance depends on wheel offset, suspension travel and body dimensions that no tire size contains. This page tells you exactly what changes dimensionally, which is the part that can be calculated.
Related comparisons
Other tire maths on this site
- tire size calculatorRead any tire size code and get overall diameter, sidewall height, circumference and revolutions per mile, with the arithmetic shown.
- tire size comparisonPut two sizes side by side and see the difference in diameter, width, sidewall, ground clearance and speedometer reading.
- tire size chartEvery common size sorted by wheel diameter, with overall diameter in inches and millimeters and revolutions per mile.
- tire diameter calculatorOverall diameter, radius and rolling circumference from the size code, and the reverse — the sizes that produce a diameter you want.
- speedometer error calculatorHow far out your speedometer and odometer read after a tire size change, at any indicated speed.
- plus sizing calculatorLarger wheel, same rolling diameter. Plus one and plus two candidates ranked by how close they hold the original diameter.
- gear ratio calculatorThe axle ratio that restores stock engine rpm after a tire diameter change, plus cruising rpm at any speed.
- metric to inch tire conversionConvert a metric size such as 285/70R17 to its inch equivalent, and an inch size such as 33x12.50R17 back to metric.
- rim width rangeThe rim widths a size is designed to mount on, and how section width changes as the rim gets wider.
- tire size meaningWhat every character in 265/70R17 stands for, digit by digit, including the load index and speed rating.