305/45R19
305/45R19 is uncommon as OEM fitment but appears as an aftermarket upsize option. At 29.81″ diameter with a 5.40″ sidewall (45% of section width), this size turns 677 revolutions per mile.
About 305/45R19
305/45R19 is less common as a factory fitment but is available as an aftermarket size, so SKU selection is narrower than mainstream OEM sizes. At 29.81″ overall diameter, 305/45R19 turns 677 revolutions per mile, which is the reference point the factory speedometer and odometer were calibrated against. The 45% aspect ratio gives it a low-profile sidewall that delivers sharp steering response but transmits road imperfections. The 19″ rim pairing is typical for full-size truck, premium SUV, and sport-sedan platforms, so compatible wheels are easy to source new or used. Going one step shorter to 295/45R19 drops diameter by 1.19%, which stays within the ±3% fitment safe zone for most vehicles. Stepping up to 285/50R19 adds 1.39% 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 29.81″ 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 aliases305/45R19
- Diameter
- 29.81″ / 757.1mm
- Section Width
- 12.01″
- Sidewall
- 5.4″ / 137.25mm
- Circumference
- 93.64″
- Revs/Mile
- 677
285/45R19
- Diameter
- 29.1″ / 739.1mm
- Section Width
- 11.22″
- Sidewall
- 5.05″ / 128.25mm
- Circumference
- 91.42″
- Revs/Mile
- 693
Speedometer & Diameter Impact
At an indicated 60 mph, your actual speed is 58.57 mph (94.26 km/h). Your speedometer reads 2.38% high versus actual speed.