How to read a tyre size
In 205/55R16, 205 is the width in mm, 55 is the sidewall as a percentage of width, and 16 is the rim diameter in inches.
Comparing sizes
Enter your current and a new size to see the diameter difference. Staying within about 3% of the original keeps your speedometer and gearing close to stock.
Frequently asked questions
Will a bigger tyre affect my speedometer?
Yes. A larger overall diameter means you travel further per revolution, so your real speed is higher than the speedometer shows.
Is this a fitment guarantee?
No. Check clearance, load and speed ratings and your manufacturer's approved sizes before changing tyres.
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