245/40R17 tire size

A 245/40R17 tire is 24.72 inches (627.8 mm) tall, 9.65 in (245 mm) wide and fits a 17-inch wheel. In inch notation it is roughly a 24.7x9.6R17.

245/40R17 dimensions
Overall diameter	24.72 in	627.8 mm
Section width	9.65 in	245 mm
Sidewall height	3.86 in	98.0 mm
Circumference	77.65 in	1,972 mm
Revolutions	816.0 per mile	507.0 per km
Rim diameter	17 in	431.8 mm

Compare 245/40R17 with another size

Current size

New size

Speed in mphkm/h

Overall diameter difference

−0.40%

60 mph on the speedometer = 59.8 mph actual

Within the ±3 % diameter range most tire fitters accept.

Ground clearance: −1.3 mm (−0.05 in)
Revolutions: 816 → 819 per mile

245/40R17 215/45R17

Side-by-side dimensions

	Current	New	Difference	%
Diameter	24.72 in	24.62 in	−0.10 in	−0.40%
Diameter	627.8 mm	625.3 mm	−2.5 mm	−0.40%
Width	9.65 in	8.46 in	−1.18 in	−12.24%
Width	245.0 mm	215.0 mm	−30.0 mm	−12.24%
Sidewall	3.86 in	3.81 in	−0.05 in	−1.28%
Sidewall	98.0 mm	96.8 mm	−1.3 mm	−1.28%
Circumference	77.65 in	77.34 in	−0.31 in	−0.40%
Revs per mile	816.0	819.2	+3.3	+0.40%

Speedometer error

Speedometer shows	Actual speed	Difference
20 mph	19.9 mph	−0.1 mph
30 mph	29.9 mph	−0.1 mph
40 mph	39.8 mph	−0.2 mph
50 mph	49.8 mph	−0.2 mph
60 mph	59.8 mph	−0.2 mph
70 mph	69.7 mph	−0.3 mph
80 mph	79.7 mph	−0.3 mph

Alternative sizes on the same 17-inch wheel

Sizes in use within ±3 % of the overall diameter of 245/40R17:

Plus and minus sizes for 245/40R17

Size	Wheel	Diameter	Difference
225/55R15	Minus 2 (15 in)	24.74 in	+0.11%
215/60R15	Minus 2 (15 in)	25.16 in	+1.78%
245/45R16	Minus 1 (16 in)	24.68 in	−0.14%
225/50R16	Minus 1 (16 in)	24.86 in	+0.57%
215/50R16	Minus 1 (16 in)	24.46 in	−1.02%
235/50R16	Minus 1 (16 in)	25.25 in	+2.17%
285/30R18	Plus 1 (18 in)	24.73 in	+0.06%
245/35R18	Plus 1 (18 in)	24.75 in	+0.14%
215/40R18	Plus 1 (18 in)	24.77 in	+0.22%
235/35R18	Plus 1 (18 in)	24.48 in	−0.97%
245/30R19	Plus 2 (19 in)	24.79 in	+0.29%
255/30R19	Plus 2 (19 in)	25.02 in	+1.24%
225/35R19	Plus 2 (19 in)	25.20 in	+1.96%
265/30R19	Plus 2 (19 in)	25.26 in	+2.20%

Vehicles approved with 245/40R17 tires

Models whose Swiss type approval lists 245/40R17 as a standard or optional size (1,896 approvals in total). Always check your own vehicle's placard or papers.

Source: Swiss Federal Roads Office (FEDRO/ASTRA), open government data. Original data (downloaded 2026-09-29). Data processed by us; errors in processing are ours, not the publisher's.

Nearby 17-inch sizes

Reading the 245/40R17 size

245 — section width in millimetres (9.65 in).
40 — aspect ratio: the sidewall is 40 % of the width, 98.0 mm.
R — radial construction (ZR on the sidewall means a high-speed rated radial; the dimensions are the same).
17 — fits a 17-inch diameter wheel.

The load index and speed rating (for example 91V) follow the size on the sidewall. They must meet at least the values on your vehicle's tire placard.