# /40 series tire aspect ratio

## What does /40 mean in a tire size?

A /40 aspect ratio means the tire sidewall height is 40% of the section width. For a 205/40R16 tire, the sidewall is 82mm tall. Common 40-series sizes span multiple rim diameters.

- [225/40 R18](https://tirefitlab.com/225-40-r18.md)
- [235/40 R18](https://tirefitlab.com/235-40-r18.md)
- [245/40 R18](https://tirefitlab.com/245-40-r18.md)
- [245/40 R19](https://tirefitlab.com/245-40-r19.md)
- [255/40 R19](https://tirefitlab.com/255-40-r19.md)
- [275/40 R19](https://tirefitlab.com/275-40-r19.md)
- [275/40 R20](https://tirefitlab.com/275-40-r20.md)
- [295/40 R20](https://tirefitlab.com/295-40-r20.md)
- [305/40 R20](https://tirefitlab.com/305-40-r20.md)
- [265/40 R22](https://tirefitlab.com/265-40-r22.md)
- [285/40 R22](https://tirefitlab.com/285-40-r22.md)
- [305/40 R22](https://tirefitlab.com/305-40-r22.md)

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Methodology: https://tirefitlab.com/methodology/