Skip to main content
TireShopper

235/55R18 vs 295/35R20 tire size comparison

235/55R18295/35R20

295/35R20 is 0.1 in (0.17%) shorter than 235/55R18 and 2.3 in wider. They fit different wheels: 235/55R18 an 18-inch wheel and 295/35R20 a 20-inch wheel.

235/55R18 and 295/35R20 side by side

-0.1 in / -0.17%235/55R18: 28.2 in tall, solid line295/35R20: 28.1 in tall, dashed line235/55R18Width 9.3 in (235 mm)Sidewall 5.1 in (129 mm)295/35R20Width 11.6 in (295 mm)Sidewall 4.1 in (103 mm)
235/55R18 is drawn with a solid line and 295/35R20 with a dashed line. In each drawing both tires are to the same scale; the tread shoulder and bead curves are simplified. The table below has the same numbers.
Dimensions of 235/55R18 and 295/35R20, with the difference (295/35R20 minus 235/55R18)
Measurement235/55R18295/35R20DifferenceDifference %
Section width9.3 in (235 mm)11.6 in (295 mm)+2.3 in (+60 mm)+25.53%
Sidewall height5.1 in (129 mm)4.1 in (103 mm)-1.0 in (-26 mm)-20.12%
Wheel (rim) diameter18.0 in (457 mm)20.0 in (508 mm)+2.0 in (+51 mm)+11.11%
Overall diameter28.2 in (716 mm)28.1 in (715 mm)-0.1 in (-1 mm)-0.17%
Circumference88.5 in (2248 mm)88.4 in (2245 mm)-0.1 in (-3 mm)-0.17%
Revolutions per mile716717+1+0.17%

Differences are 295/35R20 minus 235/55R18; percentages are relative to 235/55R18. These are nominal design dimensions. Real tires vary by brand, tread depth, wheel width, load and pressure.

The overall diameter differs by 0.17%, which is within the common 3% rule of thumb.

The rule of thumb keeps a replacement size within about 3% of the original overall diameter. It covers diameter only. It is not a fit, load or safety check, because width, wheel diameter, load capacity and clearance matter too. Confirm any size change with your vehicle's owner's manual or a tire professional.

Speedometer difference

When the speedometer reads 60 mph on a vehicle built for 235/55R18, the actual speed on 295/35R20 is about 59.9 mph. When it reads 60 mph on a vehicle built for 295/35R20, the actual speed on 235/55R18 is about 60.1 mph. These figures assume the speedometer is accurate on the original size and use nominal dimensions, so treat them as estimates.

Actual speed for a given speedometer reading, 235/55R18 against 295/35R20
Speedometer readsActual on 295/35R20 (built for 235/55R18)Actual on 235/55R18 (built for 295/35R20)
20 mph20.0 mph20.0 mph
30 mph29.9 mph30.1 mph
40 mph39.9 mph40.1 mph
50 mph49.9 mph50.1 mph
60 mph59.9 mph60.1 mph
70 mph69.9 mph70.1 mph
80 mph79.9 mph80.1 mph

A common rule of thumb is to keep a replacement size within about 3% of the original overall diameter. Check the tire placard on the driver's door jamb and your owner's manual for the sizes your vehicle was built for. Confirm any size change with your vehicle's owner's manual or a tire professional.

Which vehicles use each size?

These vehicles list the size among their verified sizes, by trim. Open one to see all of its sizes.

Check it in the calculator

The calculator takes the same two sizes and shows the full comparison, or lets you swap either one for another size.

Open this comparison in the calculator

Shop for 235/55R18 or 295/35R20 tires

Confirm the size on your tire sidewall or door placard first. These links open each store's own search; prices and stock are on their sites.

We may earn a commission if you buy through these links. It doesn't change the price you pay. Read our affiliate disclosure.

Other comparisons with 235/55R18

Side-by-side dimensions and speedometer difference for sizes close to 235/55R18 in overall diameter.

Other comparisons with 295/35R20

Side-by-side dimensions and speedometer difference for sizes close to 295/35R20 in overall diameter.

You might also need

Paid links to Amazon search results. As an Amazon Associate I earn from qualifying purchases. Read our affiliate disclosure.