Contact

The fastest way to reach us is email: hello@tiresizetool.com. We usually reply within two business days.

For bug reports, please include the browser you are using and a description of what you expected to happen. If a specific tire size or vehicle fitment looks wrong, tell us the exact size (for example 225/45R17) and what you expected the diameter or speedometer difference to read, so we can check the math against the ISO/ETRTO formula.

What we can help with

• Incorrect calculations or unit conversions
• Broken pages, layout issues, or console errors
• Questions about embedding the calculator on your own site
• Data corrections for a specific size or comparison page

What we can't help with

We don't sell tires, offer roadside assistance, or give mechanical advice about your specific vehicle. For fitment questions beyond the numbers (rubbing, load rating, speed rating suitability), a local tire shop or your vehicle's manufacturer specs are a better source than a web calculator.

Before you email

Many questions are already answered on the tire size calculator itself or in the size-specific guides linked from it. Check there first; it will usually be faster than waiting on a reply.