Decode tyre size codes, calculate outer diameter and circumference, and compare two tyre sizes with speedometer correction. Australian tyre sizing reference.
Enter tyre size (e.g. 225/45R17 from sidewall of tyre)
Comparison tyre
| Metric | Tyre 1 | Tyre 2 | Diff |
|---|
Format: 225/45R17 — 225 = width in mm; 45 = aspect ratio (sidewall height as % of width); R = radial; 17 = rim diameter in inches.
Tyres also show a load index (e.g. 91 = 615kg per tyre) and speed rating (e.g. V = up to 240 km/h). Always match or exceed the manufacturer's recommended ratings listed in your owner's manual or door placard.