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245/35R18 tire size

245/35R18 is a metric size: 24.8" tall, 9.6" wide, on a 18" rim — about a 25x9.50R18. The sidewall is 3.4" and the tire turns 815 times per mile.

Diameter 24.8" sidewall 3.38" 18" rim width 245 mm (9.6")
245/35R18: 245 mm wide, sidewall 35% of the width (3.38"), on a 18" rim → 24.75" tall.

245/35R18 specs

Overall diameter (height)24.75" · 629 mm
Section width9.65" · 245 mm
Sidewall height3.38" · 86 mm (35% of width)
Rim diameter18"
Circumference77.76" · 1.975 m
Revolutions per mile815 (506 per km)
Inch (flotation) equivalent25x9.50R18

Equivalent sizes on a 18" rim

Sizes within ±5% of the overall diameter. Green rows are inside the usual ±3% limit for keeping the speedometer, ABS and gearing right; red rows are bigger changes that need clearance checks.

SizeDiameterDifferenceWidthSpeedo at 60
245/40R18 common25.72"+3.90%0 mm62.3 mphcompare →
225/45R18 common25.97"+4.93%-20 mm63.0 mphcompare →
225/40R18 common25.09"+1.35%-20 mm60.8 mphcompare →
235/40R18 common25.40"+2.62%-10 mm61.6 mphcompare →
255/35R18 common25.03"+1.11%+10 mm60.7 mphcompare →
275/35R18 common25.58"+3.34%+30 mm62.0 mphcompare →
265/35R18 common25.30"+2.23%+20 mm61.3 mphcompare →
215/45R18 common25.62"+3.50%-30 mm62.1 mphcompare →
215/40R1824.77"+0.08%-30 mm60.0 mphcompare →
285/35R1825.85"+4.45%+40 mm62.7 mphcompare →
295/30R1824.97"+0.87%+50 mm60.5 mphcompare →
285/30R1824.73"-0.08%+40 mm60.0 mphcompare →
315/30R1825.44"+2.78%+70 mm61.7 mphcompare →
205/40R1824.46"-1.19%-40 mm59.3 mphcompare →
335/30R1825.91"+4.69%+90 mm62.8 mphcompare →
225/35R1824.20"-2.23%-20 mm58.7 mphcalculate →
215/35R1823.93"-3.34%-30 mm58.0 mphcalculate →
235/35R1824.48"-1.11%-10 mm59.3 mphcalculate →
305/30R1825.20"+1.83%+60 mm61.1 mphcalculate →
155/60R1825.32"+2.31%-90 mm61.4 mphcalculate →
205/35R1823.65"-4.45%-40 mm57.3 mphcalculate →
235/30R1823.55"-4.85%-10 mm57.1 mphcalculate →
205/45R1825.26"+2.07%-40 mm61.2 mphcalculate →

Plus / minus sizing: 17" and 19" rims

Same overall height on a different rim. Check wheel width and clearance before switching.

SizeDiameterDifferenceWidthSpeedo at 60
225/45R17 common24.97"+0.89%-20 mm60.5 mphcompare →
215/45R17 common24.62"-0.54%-30 mm59.7 mphcompare →
245/40R17 common24.72"-0.14%0 mm59.9 mphcompare →
275/35R1724.58"-0.70%+30 mm59.6 mphcalculate →
245/30R1924.79"+0.14%0 mm60.1 mphcalculate →
295/25R1924.81"+0.22%+50 mm60.1 mphcalculate →
215/35R1924.93"+0.70%-30 mm60.4 mphcalculate →
235/30R1924.55"-0.81%-10 mm59.5 mphcalculate →
145/70R1724.99"+0.97%-100 mm60.6 mphcalculate →

Try another size against 245/35R18

Questions

What size is 245/35R18 in inches?

245/35R18 is about 24.8" tall and 9.6" wide on a 18-inch rim — roughly a 25x9.50R18 in inch sizing.

What does 245/35R18 mean?

245 mm section width, sidewall 35% of the width (3.38"), radial construction, 18-inch rim.

What tire sizes are equivalent to 245/35R18?

On the same 18" rim, within 3% of the diameter: 285/30R18 (-0.08%), 215/40R18 (+0.08%), 295/30R18 (+0.87%), 235/35R18 (-1.11%), 255/35R18 (+1.11%), 205/40R18 (-1.19%).

How many revolutions per mile does a 245/35R18 tire make?

About 815 revolutions per mile (circumference 77.8").

How these numbers are computed

Diameter = rim + 2 × sidewall, sidewall = width × aspect ÷ 100, circumference = π × diameter, revolutions per mile = 63,360 ÷ circumference. Real tires differ by brand by a few tenths of an inch. Last reviewed October 14, 2026.