CarSpecsHQ

215/50R18 tire size

215/50R18 is a metric size: 26.5" tall, 8.5" wide, on a 18" rim — about a 26.5x8.50R18. The sidewall is 4.2" and the tire turns 762 times per mile.

Diameter 26.5" sidewall 4.23" 18" rim width 215 mm (8.5")
215/50R18: 215 mm wide, sidewall 50% of the width (4.23"), on a 18" rim → 26.46" tall.

215/50R18 specs

Overall diameter (height)26.46" · 672 mm
Section width8.46" · 215 mm
Sidewall height4.23" · 108 mm (50% of width)
Rim diameter18"
Circumference83.14" · 2.112 m
Revolutions per mile762 (474 per km)
Inch (flotation) equivalent26.5x8.50R18

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
225/45R18 common25.97"-1.86%+10 mm58.9 mphcompare →
245/40R18 common25.72"-2.83%+30 mm58.3 mphcompare →
245/45R18 common26.68"+0.82%+30 mm60.5 mphcompare →
235/50R18 common27.25"+2.98%+20 mm61.8 mphcompare →
235/45R18 common26.33"-0.52%+20 mm59.7 mphcompare →
235/40R18 common25.40"-4.02%+20 mm57.6 mphcompare →
225/50R18 common26.86"+1.49%+10 mm60.9 mphcompare →
225/55R18 common27.74"+4.83%+10 mm62.9 mphcompare →
255/40R18 common26.03"-1.64%+40 mm59.0 mphcompare →
245/50R18 common27.65"+4.46%+30 mm62.7 mphcompare →
275/35R18 common25.58"-3.35%+60 mm58.0 mphcompare →
265/35R18 common25.30"-4.39%+50 mm57.4 mphcompare →
255/45R18 common27.04"+2.16%+40 mm61.3 mphcompare →
215/55R18 common27.31"+3.20%0 mm61.9 mphcompare →
275/40R18 common26.66"+0.74%+60 mm60.4 mphcompare →
215/45R18 common25.62"-3.20%0 mm58.1 mphcompare →
265/40R1826.35"-0.45%+50 mm59.7 mphcompare →
285/35R1825.85"-2.31%+70 mm58.6 mphcompare →
315/30R1825.44"-3.87%+100 mm57.7 mphcompare →
295/35R1826.13"-1.26%+80 mm59.2 mphcompare →
335/30R1825.91"-2.08%+120 mm58.8 mphcompare →
275/45R1827.74"+4.83%+60 mm62.9 mphcompare →
295/40R1827.29"+3.12%+80 mm61.9 mphcompare →
265/45R1827.39"+3.50%+50 mm62.1 mphcompare →
285/40R1826.98"+1.93%+70 mm61.2 mphcalculate →
305/35R1826.41"-0.22%+90 mm59.9 mphcalculate →
345/35R1827.51"+3.94%+130 mm62.4 mphcalculate →
305/40R1827.61"+4.31%+90 mm62.6 mphcalculate →
155/70R1826.54"+0.30%-60 mm60.2 mphcalculate →
26x12.00R1826.00"-1.76%+90 mm58.9 mphcalculate →
26x6.00R1826.00"-1.76%-63 mm58.9 mphcalculate →
26x8.00R1826.00"-1.76%-12 mm58.9 mphcalculate →
145/70R1825.99"-1.79%-70 mm58.9 mphcalculate →
325/35R1826.96"+1.86%+110 mm61.1 mphcalculate →
165/70R1827.09"+2.38%-50 mm61.4 mphcalculate →
145/80R1827.13"+2.53%-70 mm61.5 mphcalculate →
155/60R1825.32"-4.31%-60 mm57.4 mphcalculate →
145/85R1827.70"+4.69%-70 mm62.8 mphcalculate →
305/30R1825.20"-4.76%+90 mm57.1 mphcalculate →
315/35R1826.68"+0.82%+100 mm60.5 mphcalculate →
345/30R1826.15"-1.19%+130 mm59.3 mphcalculate →
195/60R1827.21"+2.83%-20 mm61.7 mphcalculate →
205/45R1825.26"-4.54%-10 mm57.3 mphcalculate →
205/60R1827.69"+4.61%-10 mm62.8 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
245/40R19 common26.72"+0.95%+30 mm60.6 mphcompare →
215/55R17 common26.31"-0.58%0 mm59.7 mphcompare →
235/40R19 common26.40"-0.24%+20 mm59.9 mphcompare →
275/35R19 common26.58"+0.43%+60 mm60.3 mphcompare →
235/50R17 common26.25"-0.80%+20 mm59.5 mphcompare →
265/35R19 common26.30"-0.61%+50 mm59.6 mphcompare →
305/30R1926.20"-0.98%+90 mm59.4 mphcompare →
325/30R1926.68"+0.80%+110 mm60.5 mphcompare →
245/50R1726.65"+0.68%+30 mm60.4 mphcompare →
315/30R1926.44"-0.09%+100 mm59.9 mphcompare →
335/35R1726.23"-0.88%+120 mm59.5 mphcalculate →
195/60R1726.21"-0.95%-20 mm59.4 mphcalculate →
195/50R1926.68"+0.80%-20 mm60.5 mphcalculate →
295/40R1726.29"-0.65%+80 mm59.6 mphcalculate →
205/60R1726.69"+0.83%-10 mm60.5 mphcalculate →

Try another size against 215/50R18

Questions

What size is 215/50R18 in inches?

215/50R18 is about 26.5" tall and 8.5" wide on a 18-inch rim — roughly a 26.5x8.50R18 in inch sizing.

What does 215/50R18 mean?

215 mm section width, sidewall 50% of the width (4.23"), radial construction, 18-inch rim.

What tire sizes are equivalent to 215/50R18?

On the same 18" rim, within 3% of the diameter: 305/35R18 (-0.22%), 155/70R18 (+0.30%), 265/40R18 (-0.45%), 235/45R18 (-0.52%), 275/40R18 (+0.74%), 245/45R18 (+0.82%).

How many revolutions per mile does a 215/50R18 tire make?

About 762 revolutions per mile (circumference 83.1").

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.