# 275/45 R21

## What size is 275/45 R21?

275/45 R21 has an overall diameter of about 30.74 in, a section width of 10.83 in and a sidewall height of 4.87 in. It turns roughly 656 times per mile. Below are the exact figures plus in-tolerance plus/minus sizes you can switch to safely.

## Specification

| Specification | |
|---|---|
| Overall diameter | 30.74 in |
| Section width | 10.83 in |
| Sidewall height | 4.87 in |
| Circumference | 96.59 in |
| Revolutions | 408 /km · 656 /mi |

## In-tolerance sizes

| Size | Diameter | Speedo | Verdict |
|---|---|---|---|
| [265/70 R16](https://tirefitlab.com/265-70-r16.md) | -0.4% | -0.4% | ✓ OK |
| [275/55 R19](https://tirefitlab.com/275-55-r19.md) | +0.5% | +0.5% | ✓ OK |
| [265/65 R17](https://tirefitlab.com/265-65-r17.md) | -0.6% | -0.6% | ✓ OK |
| [245/65 R18](https://tirefitlab.com/245-65-r18.md) | -0.7% | -0.7% | ✓ OK |
| [265/60 R18](https://tirefitlab.com/265-60-r18.md) | -0.7% | -0.7% | ✓ OK |
| [285/40 R22](https://tirefitlab.com/285-40-r22.md) | +0.8% | +0.8% | ✓ OK |
| [245/70 R17](https://tirefitlab.com/245-70-r17.md) | -0.8% | -0.8% | ✓ OK |
| [31x10.50 R15](https://tirefitlab.com/31x10.50-r15.md) | +0.8% | +0.8% | ✓ OK |
| [31x10.50 R16](https://tirefitlab.com/31x10.50-r16.md) | +0.8% | +0.8% | ✓ OK |
| [265/50 R20](https://tirefitlab.com/265-50-r20.md) | -1.0% | -1.0% | ✓ OK |
| [265/45 R21](https://tirefitlab.com/265-45-r21.md) | -1.2% | -1.2% | ✓ OK |
| [265/40 R22](https://tirefitlab.com/265-40-r22.md) | -1.3% | -1.3% | ✓ OK |

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Methodology: https://tirefitlab.com/methodology/ · Tire size calculator: https://tirefitlab.com/275-45-r21/

> Geometry is computed in canonical millimetres and is deterministic across the site. Always verify physical clearance before fitting.