10 December 20244 min readBristol, UK
Those numbers on your tyre sidewall tell you everything you need to know — width, height, rim size, load rating, and speed index. Here's how to decode them in plain English.
A tyre like "205/55 R16 91V" might look cryptic but it's a precise specification. 205 is the tyre width in millimetres. 55 is the aspect ratio (sidewall height as a percentage of width). R means radial construction. 16 is the rim diameter in inches. 91 is the load index, and V is the speed rating. Getting the right specification is essential — using the wrong size can affect your speedo accuracy, handling, and MOT.
KEY TAKEAWAYS
- Width comes first — e.g. 205 means 205mm wide
- "R" stands for radial — the construction type used on all modern tyres
- Aspect ratio affects ride comfort — lower numbers mean sportier feel
- Always match load and speed index to manufacturer specs
- Our team can decode your tyre size and find the right replacement instantly
#Tyre Sizes#Sidewall Markings#Tyre Guide