Tyre Size Calculator & Comparison
TyreDispatch.co.nz v3.1
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Compare up to 4 tyre sizes side-by-side. See how width, sidewall height, and diameter changes affect your speedometer, WOF compliance, ride comfort, and grip.
Enter Tyre Sizes
Selected Sizes
Specifications
How to Read Tyre Sizes
Metric205 / 55 / R16
205mm width. Sidewall = 55% of 205mm (112.75mm). 16" rim
Imperial31 / 10.5 / R15
31" overall diameter. 10.5" width. 15" rim
Visual Comparison
Front View
Enter sizes and click Calculate
Side View
Speedometer Impact
| Your speedo reads | Actual speed (T2) | Actual speed (T3) | Actual speed (T4) |
|---|
Assumes your speedometer was calibrated for Tyre 1 (your original size). Actual vehicle speedometers also have manufacturer tolerances of up to 4%.
NZ WOF Compliance Check
Shop Similar Sizes
Alternative tyre sizes with a similar overall diameter to Tyre 1. All WOF-compliant options.
| Size | Diameter | Sidewall | Width |
|---|
Sizes shown are common NZ fitments within +/-5% diameter of Tyre 1.
Need a specific size? Get a quote
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