215/40R17 Tire Size
215/40R17 diameter, sidewall, revolutions per mile, and plus-sizing options.
The 215/40R17 tire size breaks down as: 215 mm section width, 40% aspect ratio, and a 17-inch rim. Below are its real, calculated dimensions.
215/40R17 Calculated Dimensions
| Metric | Value |
|---|---|
| Overall diameter | 23.8 in (604 mm) |
| Sidewall height | 3.4 in (86 mm) |
| Circumference | 74.7 in (1897 mm) |
| Revolutions per mile | 848 |
Typical Fitment
215/40R17 is most often found on tuned sport compacts. Always confirm against the door-jamb placard or owner manual before fitting.
Plus-Sizing Alternatives
These sizes keep the overall diameter close to 215/40R17, so speedometer and gearing stay near stock:
| Size | Diameter | Diameter change |
|---|---|---|
| 225/40R17 | 24.09 in | +1.3% |
| 225/35R18 | 24.20 in | +1.8% |
| 235/25R19 | 23.63 in | -0.6% |
Speedometer Note
If you fit a 225/40R17 instead of 215/40R17, the diameter changes by +1.3%. A taller tire makes your speedometer read low — at a true 60 mph it would show roughly 59 mph. A shorter tire has the opposite effect, so the gauge reads high.
Use the tire calculator to compare 215/40R17 against any other size and see the exact diameter and speedometer difference.
Frequently Asked Questions
What does 215/40R17 mean?
215/40R17 means a 215 mm wide tire with a 40% sidewall aspect ratio mounted on a 17-inch rim. The aspect ratio is the sidewall height as a percentage of the width.
Can I plus-size from 215/40R17?
Yes, as long as the replacement keeps the overall diameter close to stock so the speedometer stays accurate. Common plus-size moves from 215/40R17 are 225/40R17, 225/35R18, 235/25R19.
Will 215/40R17 affect my speedometer?
Only if it differs in diameter from your original size. A taller tire reads low; a shorter tire reads high. Compare the two sizes with the calculator to find the percentage.