Car Tire Size Calc

Compare two tire + rim setups side by side. See speedometer error, clearance change, offset/stance shift, and export results as PDF. Metric or imperial.

Compare your current tires and rims to a new setup before you buy. Upgrade with confidence and see exactly how changes affect your vehicle's performance. Tire Size Calculator shows speedometer error, clearance change, sidewall height, circumference, rim offset (ET), and wheel stance shift — with metric or imperial units.

Share or print PDF report with mechanic or friend.

• Speedometer Accuracy: Instantly check speedometer differences to avoid miscalculations.
• Ground Clearance Impact: See how new tire sizes influence your car’s ride height.
• Multiple Unit Support: Choose between Metric and Imperial measurements for convenience.
• User-Friendly Interface: Designed for quick and easy comparisons—no complex formulas required!

Make informed decisions and optimise your vehicle’s performance with precision. Perfect for upsizing wheels, checking plus-sizing, or verifying fitment before installation.