TireSizeCheck

265/55R19 vs 255/60R19

Fitment assessment

Fitment not determined

Diameter change

+1.9%

Overall diameter changes 1.9%; section width changes -10 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

31.05″

was 30.48″

True speed at an indicated 60

61.1 mph

your speedo reads low

Revolutions per mile

650

was 662, −12

Measurement 265/55R19 255/60R19 Change
Overall diameter 30.48″ 31.05″ +0.57″ (+1.9%)
Sidewall height 5.74″ (145.8 mm) 6.02″ (153.0 mm) +7.3 mm
Tread width 265 mm 255 mm −10 mm
Circumference 95.74″ 97.54″ +1.79″
Revs per mile 662 650 −12
Speedometer error baseline +1.9% reads low

Diameter overlay

265/55R19 255/60R19

Speedometer check

With 255/60R19 fitted, when the speedometer shows the indicated speed, your actual speed is:

25 mph shown

25.5 mph actual

35 mph shown

35.7 mph actual

45 mph shown

45.8 mph actual

55 mph shown

56.0 mph actual

65 mph shown

66.2 mph actual

75 mph shown

76.4 mph actual

Common questions

Will 255/60R19 fit instead of 265/55R19?
Overall diameter changes 1.9%; section width changes -10 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 30.48″ to 31.05″, a change of +1.9%. 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 255/60R19?
At an indicated 60 mph you are really doing about 61.1 mph, a +1.9% error. The speedometer reads low, so you are going faster than it shows.
What is the difference in revolutions per mile between 265/55R19 and 255/60R19?
265/55R19 turns about 662 times per mile and 255/60R19 turns about 650, a difference of −12. Your speedometer and odometer both count rotations, so this number is what throws them off.