245/60R20
245/60R20 ships as an OEM size on the Toyota 4Runner. At 31.57″ diameter with a 5.79″ sidewall (60% of section width), this size turns 639 revolutions per mile.
About 245/60R20
Factory fitments for 245/60R20 include the Toyota 4Runner — meaning replacement tires in this size see steady demand and broad brand availability. At 31.57″ overall diameter, 245/60R20 turns 639 revolutions per mile, which is the reference point the factory speedometer and odometer were calibrated against. The 60% aspect ratio gives it a balanced sidewall — enough compliance for daily comfort without vague steering. The 20″ rim pairing is typical for luxury SUV and performance-oriented platforms, so compatible wheels are easy to source new or used. Going one step shorter to 235/60R20 drops diameter by 1.50%, which stays within the ±3% fitment safe zone for most vehicles. Stepping up to 235/65R20 adds 1.43% diameter — also inside the safe window, with marginally taller ride height. If you are shopping for a direct replacement, any tire within roughly ±0.7″ of the 31.57″ stock diameter (about ±2% in percentage terms) will keep ABS, TPMS, and odometer readings inside the vehicle's designed tolerance.
Compare with another size
275/65R18 or "33" for inch aliases245/60R20
- Diameter
- 31.57″ / 802mm
- Section Width
- 9.65″
- Sidewall
- 5.79″ / 147mm
- Circumference
- 99.2″
- Revs/Mile
- 639
235/55R20
- Diameter
- 30.18″ / 766.5mm
- Section Width
- 9.25″
- Sidewall
- 5.09″ / 129.25mm
- Circumference
- 94.8″
- Revs/Mile
- 668
Speedometer & Diameter Impact
At an indicated 60 mph, your actual speed is 57.34 mph (92.29 km/h). Your speedometer reads 4.43% high versus actual speed.