255/45R19 vs 225/55R19
225/55R19 is taller than 255/45R19 by 2.53% — a diameter difference of 0.70″.
What changes between 255/45R19 and 225/55R19
Switching from 255/45R19 to 225/55R19 changes overall diameter by +2.53%, a taller tire by 0.70 inches. This lands inside the ±3% fitment safe zone, so most vehicles will accept the swap without rubbing, speedometer recalibration, or ABS/TPMS complications. Section width moves by -1.18″ (255mm → 225mm), which affects contact patch and fender-well clearance. Sidewall height shifts by +0.35″: a taller sidewall softens ride quality and adds off-road bump protection, with some loss of steering crispness. Revs per mile moves by -17, which translates directly to speedometer error — at an indicated 65 mph, actual speed becomes 66.6 mph. Both sizes share the same 19″ rim, so no wheel change is required — this is a pure tire-only swap.
| Spec | 255/45R19 | 225/55R19 |
|---|---|---|
| Overall diameter | 28.04″ | 28.74″ |
| Section width | 10.04″ (255 mm) | 8.86″ (225 mm) |
| Sidewall height | 4.52″ (45%) | 4.87″ (55%) |
| Rim diameter | 19″ | 19″ |
| Circumference | 88.08″ | 90.3″ |
| Revs per mile | 719 | 702 |
Interactive comparison
275/65R18 or "33" for inch aliases255/45R19
- Diameter
- 28.04″ / 712.1mm
- Section Width
- 10.04″
- Sidewall
- 4.52″ / 114.75mm
- Circumference
- 88.08″
- Revs/Mile
- 719
225/55R19
- Diameter
- 28.74″ / 730.1mm
- Section Width
- 8.86″
- Sidewall
- 4.87″ / 123.75mm
- Circumference
- 90.3″
- Revs/Mile
- 702
Speedometer & Diameter Impact
Narrower tire — verify wheel widthAt an indicated 60 mph, your actual speed is 61.52 mph (99 km/h). Your speedometer reads 2.53% low versus actual speed.