Mazda Tire Size Calculator
Compare OEM vs plus-size tire options for Mazda3, CX-5, and CX-30 — instant diameter difference and speedometer error check.
Quick Example
A CX-5 (base) ships with 225/65R16 (27.5" diameter). Plus-sizing to 225/60R17 (27.6") keeps the diameter almost identical — a +0.4% change, well inside the safe zone, so your speedometer stays accurate. Enter your exact model and target size below for the precise number.
OEM diameter: 27.52"
Diameter: 27.63"
Diameter Difference
+0.41%
225/65R16 225/60R17 (+0.11")
Speedo Error
+0.41%
OEM Revs/Mile
733
New Revs/Mile
730
Safe Threshold
±3%
AI Insight
Powered by AIGet a plain-English explanation of your results — what they mean for your vehicle and driving experience.
Mazda Tire Guide
Full model lineup including MX-5 Miata — see the dedicated Miata Tire Calculator for that model.
Common Mazda Plus-Sizing Examples
| Model | OEM Size | Target Size | Diff % |
|---|---|---|---|
| Mazda3 Sedan Sport | 205/60R16 (25.7") | 215/45R18 (25.6") | -0.3% |
| CX-5 (base) | 225/65R16 (27.5") | 225/60R17 (27.6") | +0.4% |
| CX-5 Signature/2.5T | 225/55R19 (28.7") | 235/50R19 (28.3") | -1.7% |
| CX-30 | 215/55R18 (27.3") | 225/50R18 (26.9") | -1.7% |
Diameters computed via Rim × 25.4 + 2 × (Width × Aspect ÷ 100). Always verify against your door-jamb placard.
How to Use This Calculator
- Select your Mazda model to load its OEM tire size.
- Enter the target tire size you're considering.
- Review the diameter difference, speedometer error, and fitment verdict.