Tire size comparison
225/55R19 vs 235/50R19
235/50R19 is −1.7% shorter than 225/55R19: 28.3 in vs 28.7 in (−0.49 in), and 0.4 in wider. With 235/50R19 on a vehicle set up for 225/55R19, the speedometer shows 60 mph at an actual 59.0 mph. That is within the ±3% difference many shops use as a rule of thumb (not a manufacturer or legal limit).
Set up for: checking a replacement size (235/50R19 instead of 225/55R19) · Different situation?
Your current size
e.g. 265/70R17, 2657017 or 33x12.50R20
Where do I find my size?
It's on the tire sidewall, e.g. P265/70R17 115T, and on the tire placard sticker on the driver's door jamb (also in the owner's manual). The placard shows the size the vehicle came with; the sidewall shows what is fitted now. If they differ, use the placard as your starting point. Digits are enough here: 2657017 or 33125020.
Size you're considering
225/55R19 vs 235/50R19: full comparison
| 225/55R19 | 235/50R19 | Difference | |
|---|---|---|---|
| Overall diameter | 28.74 in | 28.25 in | −0.49 in (−1.7%) |
| Width | 8.86 in | 9.25 in | +0.39 in (+4.4%) |
| Sidewall height | 4.87 in | 4.63 in | −0.25 in |
| Circumference | 90.3 in | 88.8 in | −1.5 in |
| Revs per mile (nominal) | 702 | 714 | +12 |
| Wheel diameter | 19 in | 19 in | ±0 in |
| Diameter in mm | 730 | 718 | −13 mm |
Speedometer difference
Your speedometer is calibrated for 225/55R19. Fitted with 235/50R19, the actual speed is the reading × 28.25 ÷ 28.74.
| Speedometer shows | Actual speed | Difference |
|---|---|---|
| 20 mph | 19.7 mph | −0.3 mph |
| 30 mph | 29.5 mph | −0.5 mph |
| 45 mph | 44.2 mph | −0.8 mph |
| 55 mph | 54.1 mph | −0.9 mph |
| 60 mph | 59.0 mph | −1.0 mph |
| 70 mph | 68.8 mph | −1.2 mph |
| 80 mph | 78.6 mph | −1.4 mph |
Real tires: published diameters
225/55R19: 28.5–29.1 in published by 7 makers; 235/50R19: 28–28.6 in published by 7 makers. Calculated figures assume a nominal tire; the exact difference between two specific tires depends on their models.
More about each size: 225/55R19 · 235/50R19
Related comparisons
FAQ
Which is bigger, 225/55R19 or 235/50R19?
235/50R19 is −1.7% shorter than 225/55R19: 28.3 in vs 28.7 in (−0.49 in).
How much will my speedometer be off with 235/50R19 instead of 225/55R19?
The speedometer is calibrated for 225/55R19. With 235/50R19 it shows 60 mph when you are doing 59.0 mph, and 70 mph at 68.8 mph (−1.7%). Your speedometer also has its own factory tolerance.
Can I replace 225/55R19 with 235/50R19?
The diameter difference is −1.7%. Whether it fits depends on things this calculation can't see: wheel width and offset, clearance at full lock and over bumps, load index and speed rating, and your vehicle maker's approval. Check your door-jamb placard and owner's manual and ask a tire professional.