275/45R21 tire size
A 275/45R21 tire stands 30.7 inches tall and 10.8 inches wide, with a 4.9-inch sidewall on a 21-inch rim.
- Overall height
- 30.7 in781 mm
- Section width
- 10.8 in275 mm
- Sidewall height
- 4.9 in124 mm
- Rim diameter
- 21 in533 mm
- Circumference
- 96.6 in2453 mm
- Revolutions per mile
- 656408 per km
- Inch size
- 30.7x10.8R21
Compare it with any other size in the tire size calculator.
Sizes you can swap to
These 21-inch sizes are within two width steps and 3% of a 275/45R21's overall height, the usual limit before the speedometer, ABS and transmission notice. The closest is 255/50R21, 1.0% taller (0.30 in). Wider sizes also need room in the wheel well and a rim width that suits them.
Plus and minus sizes
Changing rim size means changing the sidewall to keep the same overall height. On 19-inch or 20-inch or 22-inch rims, these are the closest matches to a 275/45R21.
Other 21-inch sizes near 275/45R21
275 mm wide, other sidewalls
45 series, other widths
See the other sizes for this rim on 21-inch tire sizes, or other tires about this tall on 31-inch tires.
Shop 275/45R21 tires
These open each store's own list of 275/45R21 tires, where you can filter by type, load and speed rating.
275/45R21 questions
How tall is a 275/45R21 tire?
About 30.7 inches (781 mm) from the ground to the top of the tread, unloaded. On the vehicle, carrying weight, it sits a little lower.
What does 275/45R21 mean?
275 is the section width in millimetres (10.8 in). 45 means the sidewall is 45% of that width: 124 mm, or 4.9 in. R means radial construction, and 21 is the rim diameter in inches.
Can I use 265/45R21 instead of 275/45R21?
265/45R21 is 1.2% shorter (0.35 in) and 10 mm narrower, which is inside the usual 3% rule. With it fitted, the speedometer shows 60 mph when you are doing 59.3 mph.
What is 275/45R21 in inches?
In inch terms it is 30.7x10.8R21: 30.7 inches tall, 10.8 inches wide, for a 21-inch rim.
How many revolutions per mile does a 275/45R21 make?
About 656 turns per mile, worked out from its unloaded circumference of 96.6 inches. Makers list slightly higher numbers for their own tires, because a loaded tire rolls on a smaller radius.