225/45R13 tire size
225/45R13 is a metric size: 21.0" tall, 8.9" wide, on a 13" rim — about a 21x9.00R13. The sidewall is 4.0" and the tire turns 962 times per mile.
225/45R13 specs
| Overall diameter (height) | 20.97" · 533 mm |
|---|---|
| Section width | 8.86" · 225 mm |
| Sidewall height | 3.99" · 101 mm (45% of width) |
| Rim diameter | 13" |
| Circumference | 65.89" · 1.674 m |
| Revolutions per mile | 962 (598 per km) |
| Inch (flotation) equivalent | 21x9.00R13 |
Equivalent sizes on a 13" rim
Sizes within ±5% of the overall diameter. Green rows are inside the usual ±3% limit for keeping the speedometer, ABS and gearing right; red rows are bigger changes that need clearance checks.
| Size | Diameter | Difference | Width | Speedo at 60 | |
|---|---|---|---|---|---|
| 255/40R13 | 21.03" | +0.28% | +30 mm | 60.2 mph | calculate → |
| 165/65R13 | 21.44" | +2.25% | -60 mm | 61.4 mph | calculate → |
| 215/50R13 | 21.46" | +2.35% | -10 mm | 61.4 mph | calculate → |
| 155/70R13 | 21.54" | +2.72% | -70 mm | 61.6 mph | calculate → |
Try another size against 225/45R13
Questions
What size is 225/45R13 in inches?
225/45R13 is about 21.0" tall and 8.9" wide on a 13-inch rim — roughly a 21x9.00R13 in inch sizing.
What does 225/45R13 mean?
225 mm section width, sidewall 45% of the width (3.99"), radial construction, 13-inch rim.
What tire sizes are equivalent to 225/45R13?
On the same 13" rim, within 3% of the diameter: 255/40R13 (+0.28%), 165/65R13 (+2.25%), 215/50R13 (+2.35%), 155/70R13 (+2.72%).
How many revolutions per mile does a 225/45R13 tire make?
About 962 revolutions per mile (circumference 65.9").
How these numbers are computed
Diameter = rim + 2 × sidewall, sidewall = width × aspect ÷ 100, circumference = π × diameter, revolutions per mile = 63,360 ÷ circumference. Real tires differ by brand by a few tenths of an inch. Last reviewed October 14, 2026.