Tire size
255/50 R19
Full dimensions and a live comparison calculator for the 255/50 R19 tire size.
Overall diameter
737.6 mm
29.04″
Sidewall height
127.5 mm
Circumference
2.317 m
Revs / km
431.5
Section width
255 mm
Aspect ratio
50%
Rim diameter
19″
482.6 mm
Radius
368.8 mm
What does 255/50 R19 mean?
The 255 is the section width in millimetres, measured sidewall to sidewall. The 50 is the aspect ratio — sidewall height as a percentage of width, so the sidewall here is 127.5 mm. The R19 means a radial-construction tire designed for a 19-inch wheel rim. Together these give an overall diameter of 738 mm.
Compare 255/50 R19 with another size
Current Tire
New Tire
Fitment · Scaled comparison
● Not recommended
Diameter
-103.3 mm
-14.00%
Sidewall
-26.3 mm
Speedometer
86.0 km/h
at true 100
Clearance
Not recommended
Ground line · Scaled comparison
Not Recommended
Over 5% — speedometer & ABS may misread
Diameter change
-103.3 mm
-14.00%
Speedometer at 100
86.0 km/h
-14.00% error
Ground clearance
-51.6 mm
ride height delta
Sidewall change
-26.3 mm
revs/km: 501.8
Permalink for this comparison:
/compare/255-50-r19-vs-225-45-r17Common alternatives to 255/50 R19
These sizes are within a few percent overall diameter — usually safe on the same vehicle from a speedometer-error standpoint.
Common plus-size upgrades
+1 and +2 inch fitments within OEM tolerance — diameter delta and verdict for each upgrade.
255/50 R19 → 255/45 R20
+1 inch — OEM-safe diameter match
-0.01% diameter
255/50 R19 → 295/35 R21
+2 inch — OEM-safe diameter match
+0.31% diameter
255/50 R19 → 285/35 R21
+2 inch — OEM-safe diameter match
-0.64% diameter
255/50 R19 → 295/40 R20
+1 inch — OEM-safe diameter match
+0.87% diameter
255/50 R19 → 265/40 R21
+2 inch — common sport upgrade
+1.06% diameter
255/50 R19 → 245/45 R20
+1 inch — common sport upgrade
-1.23% diameter
Drivers also searched
Semantically close sizes — same width, nearby aspect, or matching rim families.
Related topics
Plus-size upgrades from 255/50 R19
Fitment safety note
Overall diameter, speedometer error and circumference are only part of the picture. Physical clearance, wheel offset (ET), hub bore, suspension geometry, load index and your manufacturer's recommendation all decide whether a size is truly safe on your car. Always cross-check with the vehicle manual or a qualified fitter before changing tire size.