CarSpecsHQ

215/45R20 tire size

215/45R20 is a metric size: 27.6" tall, 8.5" wide, on a 20" rim — about a 27.5x8.50R20. The sidewall is 3.8" and the tire turns 730 times per mile.

Diameter 27.6" sidewall 3.81" 20" rim width 215 mm (8.5")
215/45R20: 215 mm wide, sidewall 45% of the width (3.81"), on a 20" rim → 27.62" tall.

215/45R20 specs

Overall diameter (height)27.62" · 702 mm
Section width8.46" · 215 mm
Sidewall height3.81" · 97 mm (45% of width)
Rim diameter20"
Circumference86.76" · 2.204 m
Revolutions per mile730 (454 per km)
Inch (flotation) equivalent27.5x8.50R20

Equivalent sizes on a 20" 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
245/45R20 common28.68"+3.85%+30 mm62.3 mphcalculate →
275/40R20 common28.66"+3.78%+60 mm62.3 mphcalculate →
245/40R20 common27.72"+0.36%+30 mm60.2 mphcalculate →
245/35R20 common26.75"-3.14%+30 mm58.1 mphcalculate →
255/35R20 common27.03"-2.14%+40 mm58.7 mphcalculate →
275/35R20 common27.58"-0.14%+60 mm59.9 mphcalculate →
255/40R20 common28.03"+1.50%+40 mm60.9 mphcalculate →
285/35R20 common27.85"+0.86%+70 mm60.5 mphcalculate →
315/35R20 common28.68"+3.85%+100 mm62.3 mphcalculate →
285/30R20 common26.73"-3.21%+70 mm58.1 mphcalculate →
275/30R20 common26.50"-4.06%+60 mm57.6 mphcalculate →
265/35R20 common27.30"-1.14%+50 mm59.3 mphcalculate →
235/35R2026.48"-4.13%+20 mm57.5 mphcalculate →
295/30R2026.97"-2.35%+80 mm58.6 mphcalculate →
305/30R2027.20"-1.50%+90 mm59.1 mphcalculate →
295/35R2028.13"+1.85%+80 mm61.1 mphcalculate →
305/35R2028.41"+2.85%+90 mm61.7 mphcalculate →
285/40R2028.98"+4.92%+70 mm63.0 mphcalculate →
265/30R2026.26"-4.92%+50 mm57.0 mphcalculate →
235/45R2028.33"+2.57%+20 mm61.5 mphcalculate →
265/40R2028.35"+2.64%+50 mm61.6 mphcalculate →
335/25R2026.59"-3.71%+120 mm57.8 mphcalculate →
315/30R2027.44"-0.64%+100 mm59.6 mphcalculate →
235/40R2027.40"-0.78%+20 mm59.5 mphcalculate →
335/30R2027.91"+1.07%+120 mm60.6 mphcalculate →
325/25R2026.40"-4.42%+110 mm57.3 mphcalculate →
325/30R2027.68"+0.21%+110 mm60.1 mphcalculate →
345/30R2028.15"+1.92%+130 mm61.2 mphcalculate →
345/25R2026.79"-2.99%+130 mm58.2 mphcalculate →
195/50R2027.68"+0.21%-20 mm60.1 mphcalculate →
225/40R2027.09"-1.92%+10 mm58.8 mphcalculate →
325/35R2028.96"+4.85%+110 mm62.9 mphcalculate →
175/55R2027.58"-0.14%-40 mm59.9 mphcalculate →
145/65R2027.42"-0.71%-70 mm59.6 mphcalculate →
155/60R2027.32"-1.07%-60 mm59.4 mphcalculate →
145/60R2026.85"-2.78%-70 mm58.3 mphcalculate →
165/60R2027.80"+0.64%-50 mm60.4 mphcalculate →
155/65R2027.93"+1.14%-60 mm60.7 mphcalculate →
225/45R2027.97"+1.28%+10 mm60.8 mphcalculate →
195/55R2028.44"+2.99%-20 mm61.8 mphcalculate →

Plus / minus sizing: 19" and 21" rims

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

SizeDiameterDifferenceWidthSpeedo at 60
245/45R19 common27.68"+0.23%+30 mm60.1 mphcalculate →
275/40R19 common27.66"+0.16%+60 mm60.1 mphcalculate →
245/35R2127.75"+0.48%+30 mm60.3 mphcalculate →
265/40R1927.35"-0.98%+50 mm59.4 mphcalculate →
285/30R2127.73"+0.41%+70 mm60.2 mphcalculate →
275/30R2127.50"-0.44%+60 mm59.7 mphcalculate →
305/35R1927.41"-0.77%+90 mm59.5 mphcalculate →
155/70R1927.54"-0.27%-60 mm59.8 mphcalculate →
355/30R1927.39"-0.84%+140 mm59.5 mphcalculate →
215/50R1927.46"-0.56%0 mm59.7 mphcalculate →
345/25R2127.79"+0.63%+130 mm60.4 mphcalculate →
325/25R2127.40"-0.80%+110 mm59.5 mphcalculate →
315/35R1927.68"+0.23%+100 mm60.1 mphcalculate →
225/50R1927.86"+0.87%+10 mm60.5 mphcalculate →

Try another size against 215/45R20

Questions

What size is 215/45R20 in inches?

215/45R20 is about 27.6" tall and 8.5" wide on a 20-inch rim — roughly a 27.5x8.50R20 in inch sizing.

What does 215/45R20 mean?

215 mm section width, sidewall 45% of the width (3.81"), radial construction, 20-inch rim.

What tire sizes are equivalent to 215/45R20?

On the same 20" rim, within 3% of the diameter: 175/55R20 (-0.14%), 275/35R20 (-0.14%), 195/50R20 (+0.21%), 325/30R20 (+0.21%), 245/40R20 (+0.36%), 165/60R20 (+0.64%).

How many revolutions per mile does a 215/45R20 tire make?

About 730 revolutions per mile (circumference 86.8").

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.