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How to Read Your Tyre Size
The code on a tyre sidewall tells you its dimensions and performance rating. Matching it correctly helps the tyre fit the wheel and carry the vehicle safely.
Reading the main size
A marking such as 205/55 R16 breaks down into three key measurements.
- 205 is the tyre width in millimetres.
- 55 is the sidewall height as a percentage of the width.
- R means radial construction.
- 16 is the wheel diameter in inches.
Load and speed ratings
The number and letter after the size describe the maximum load and speed capability. Use ratings approved for your vehicle; do not choose a lower rating simply to reduce cost.
Where to confirm the correct size
Check the current tyre, the vehicle handbook or the label inside the fuel flap or driver’s door. Some cars use different front and rear sizes.
Frequently asked questions
Can I fit a different tyre size?
Only fit an alternative size that the vehicle or wheel manufacturer approves. Ask a tyre professional if you are unsure.
Need a tyre check?
Visit Sona Tyres on Coventry Road or book your fitting online.