Tire Size Comparison
Compare two tire sizes side by side. See fitment, ride height, speedometer error, and plus-size matches.
OEM
Stock / original size
225/65R17
New
Size you’re considering
245/60R18
Proceed with caution
Diameter +3.7%
Diameter differs by 3.7%. Check wheel well clearance, rubbing on turns, and expect noticeable speedometer error.
Side-by-side specs
Overall diameter
28.52″29.57″+1.06″ (+3.7%)
Ride height
—0.53″+0.53″ clearance shift
Section width
8.86″9.65″+20 mm (+8.9%)
Sidewall height
5.76″5.79″+0.03″ (+0.5%)
Circumference
89.58″92.91″+3.33″ (+3.7%)
Revs / mile
707.3681.9-25.3 (-3.6%)
Visualizer
Scaled to overall diameter
OEM New
Speedometer error
Assumes Size 1 (OEM) is what the car was calibrated for
You’re actually going 60.0 mph (+0.0)
| Gauge | 10 | 20 | 30 | 40 | 50 | 60 | 70 | 80 | 90 |
|---|---|---|---|---|---|---|---|---|---|
| Actual | 10.4 | 20.7 | 31.1 | 41.5 | 51.9 | 62.2 | 72.6 | 83.0 | 93.3 |
Plus-size for a new wheel
Keep overall diameter within ±3% while changing rim diameter
Closest diameter matches
Within ±3% of OEM diameter (same rim ±2″)
How to read a tire size code
- 225 — section width in millimeters (sidewall to sidewall)
- 65 — aspect ratio: sidewall height as a % of width
- R — radial construction (most passenger tires)
- 17 — wheel (rim) diameter in inches
Diameter = rim″ + 2 × (width mm × aspect% ÷ 25.4)