275/60R18 dimensions
| Measure | Inches | Millimetres |
|---|---|---|
| Overall height | 30.99 in | 787 mm |
| Section width | 10.83 in | 275 mm |
| Sidewall height | 6.50 in | 165.0 mm |
| Wheel diameter | 18 in | 457 mm |
| Circumference | 97.4 in | 2,473 mm |
| Revolutions per mile | 650.7 |
The math
| Step | Math | Result |
|---|---|---|
| Sidewall | 275 × 60% = 165.0 mm ÷ 25.4 | 6.50 in |
| Overall height | 18 + 2 × 6.50 | 30.99 in |
| Width | 275 mm ÷ 25.4 | 10.83 in |
| Circumference | π × 30.99 | 97.4 in |
| Revs per mile | 63,360 ÷ 97.4 | 650.7 |
With a 6.5 in sidewall this is a tall sidewall with more cushion and flex. Real tires vary by brand and model, and the loaded radius under the vehicle is a bit smaller than this unloaded figure.
One step either way on a 18 in wheel
Each row changes one thing and shows the height change against 275/60R18, plus what 60 mph on the speedometer would really be if you swapped to that size.
| Change | Size | Height | Height change | 60 mph shows as | Verdict |
|---|---|---|---|---|---|
| Wider | 285/60R18 (compare) | 31.5 in | +1.5% | 60.9 mph | Close match |
| Narrower | 265/60R18 (compare) | 30.5 in | -1.5% | 59.1 mph | Close match |
| Taller sidewall | 275/65R18 (compare) | 32.1 in | +3.5% | 62.1 mph | Check clearance |
| Shorter sidewall | 275/55R18 (compare) | 29.9 in | -3.5% | 57.9 mph | Check clearance |
| Wider, shorter sidewall | 285/55R18 (compare) | 30.3 in | -2.1% | 58.7 mph | Close match |
| Narrower, taller sidewall | 265/65R18 (compare) | 31.6 in | +1.8% | 61.1 mph | Close match |
Calculated sizes within ±3% on other wheels
Plus and minus sizes that keep the overall height within about 3% (a rule of thumb from Discount Tire and 1010tires), widths within 30 mm. Calculated, not a list of tires on sale: check that a tire exists in that size.
17 in wheels (one wheel size smaller)
| Size | Height | Height change | Width change |
|---|---|---|---|
| 295/60R17 (compare) | 30.9 in | -0.2% | +20 mm |
| 255/70R17 (compare) | 31.1 in | +0.2% | -20 mm |
| 275/65R17 (compare) | 31.1 in | +0.3% | +0 mm |
| 305/60R17 (compare) | 31.4 in | +1.3% | +30 mm |
19 in wheels (one wheel size larger)
| Size | Height | Height change | Width change |
|---|---|---|---|
| 305/50R19 (compare) | 31.0 in | +0.1% | +30 mm |
| 255/60R19 (compare) | 31.0 in | +0.2% | -20 mm |
| 275/55R19 (compare) | 30.9 in | -0.3% | +0 mm |
| 285/55R19 (compare) | 31.3 in | +1.1% | +10 mm |
20 in wheels (two wheel sizes larger)
| Size | Height | Height change | Width change |
|---|---|---|---|
| 255/55R20 (compare) | 31.0 in | +0.2% | -20 mm |
| 275/50R20 (compare) | 30.8 in | -0.5% | +0 mm |
| 305/45R20 (compare) | 30.8 in | -0.6% | +30 mm |
| 285/50R20 (compare) | 31.2 in | +0.7% | +10 mm |
Try it with your numbers
Compare 275/60R18 with another size · Convert to metric or find a 33 in size · Sizes that fit my wheel
Calculated from the size alone. Real tires vary a little by brand and model, and the loaded radius is a bit smaller. Confirm the wheel width range, clearance, load index and speed rating for your vehicle. See how to read a tire size, the load index chart and the speed rating chart.
Browse: all sizes in inches · 265/70R18 · 275/65R18.