TireSizeCheck

265/70R16 vs 225/75R16

Fitment assessment

Fitment not determined

Diameter change

−4.3%

Overall diameter changes 4.3%; section width changes -40 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

29.29″

was 30.61″

True speed at an indicated 60

57.4 mph

your speedo reads high

Revolutions per mile

689

was 659, +30

Measurement 265/70R16 225/75R16 Change
Overall diameter 30.61″ 29.29″ −1.32″ (−4.3%)
Sidewall height 7.30″ (185.5 mm) 6.64″ (168.8 mm) −16.8 mm
Tread width 265 mm 225 mm −40 mm
Circumference 96.15″ 92.01″ −4.14″
Revs per mile 659 689 +30
Speedometer error baseline −4.3% reads high

Diameter overlay

265/70R16 225/75R16

Speedometer check

With 225/75R16 fitted, when the speedometer shows the indicated speed, your actual speed is:

25 mph shown

23.9 mph actual

35 mph shown

33.5 mph actual

45 mph shown

43.1 mph actual

55 mph shown

52.6 mph actual

65 mph shown

62.2 mph actual

75 mph shown

71.8 mph actual

Common questions

Will 225/75R16 fit instead of 265/70R16?
Overall diameter changes 4.3%; section width changes -40 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 30.61″ to 29.29″, a change of −4.3%. 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 225/75R16?
At an indicated 60 mph you are really doing about 57.4 mph, a −4.3% error. The speedometer reads high, so you are going slower than it shows.
What is the difference in revolutions per mile between 265/70R16 and 225/75R16?
265/70R16 turns about 659 times per mile and 225/75R16 turns about 689, a difference of +30. Your speedometer and odometer both count rotations, so this number is what throws them off.