TireSizeCheck

295/35R20 vs 265/35R20

Fitment assessment

Fitment not determined

Diameter change

−2.9%

Overall diameter changes 2.9%; section width changes -30 mm. Diameter comparison alone cannot confirm fitment. Verify the vehicle maker's approved rim width, tire load and speed ratings, and clearance at full steering lock and suspension compression. Confirm any possible ABS, traction-control, speedometer, and drivetrain effects with the vehicle maker or a qualified tire professional.

New overall diameter

27.30″

was 28.13″

True speed at an indicated 60

58.2 mph

your speedo reads high

Revolutions per mile

739

was 717, +22

Measurement 295/35R20 265/35R20 Change
Overall diameter 28.13″ 27.30″ −0.83″ (−2.9%)
Sidewall height 4.06″ (103.3 mm) 3.65″ (92.8 mm) −10.5 mm
Tread width 295 mm 265 mm −30 mm
Circumference 88.37″ 85.78″ −2.60″
Revs per mile 717 739 +22
Speedometer error baseline −2.9% reads high

Diameter overlay

295/35R20 265/35R20

Speedometer check

With 265/35R20 fitted, when the speedometer shows the indicated speed, your actual speed is:

25 mph shown

24.3 mph actual

35 mph shown

34.0 mph actual

45 mph shown

43.7 mph actual

55 mph shown

53.4 mph actual

65 mph shown

63.1 mph actual

75 mph shown

72.8 mph actual

Common questions

Will 265/35R20 fit instead of 295/35R20?
Overall diameter changes 2.9%; section width changes -30 mm. Diameter comparison alone cannot confirm fitment. Verify the vehicle maker's approved rim width, tire load and speed ratings, and clearance at full steering lock and suspension compression. Confirm any possible ABS, traction-control, speedometer, and drivetrain effects with the vehicle maker or a qualified tire professional. Overall diameter goes from 28.13″ to 27.30″, a change of −2.9%. The rule of thumb most shops use: under 3% is fine, 3 to 5% needs a clearance check, over 5% needs recalibration.
How far off will my speedometer read on 265/35R20?
At an indicated 60 mph you are really doing about 58.2 mph, a −2.9% error. The speedometer reads high, so you are going slower than it shows.
What is the difference in revolutions per mile between 295/35R20 and 265/35R20?
295/35R20 turns about 717 times per mile and 265/35R20 turns about 739, a difference of +22. Your speedometer and odometer both count rotations, so this number is what throws them off.