225/40R18 Tire Size Specifications
This tire size 225/40R18 fits 22 vehicles in our database.
Everything to know about the 225/40R18 tire size
Size geometry
A 225/40R18 tire has a 225mm section width and a 40% aspect ratio, mounted on a 18-inch rim. Sidewall height works out to 90.0mm (3.54") and overall outside diameter is 637.2mm (25.09"). At highway speed the tire completes about 500 revolutions per kilometre â your speedometer and odometer were calibrated against this number.
Direct substitute sizes
If 225/40R18 is unavailable, the closest same-diameter substitutes on the same rim are 215/42R18 and 235/38R18. Both keep your speedometer reading within 1% â safe for daily use, ABS, and stability control. Always verify load and speed ratings before swapping.
Plus / minus sizing options
For a 225/40R18 you can upsize to 235/33R19 (plus-one) to fit a larger wheel without changing the speedometer reading, or downsize to 215/48R17 (minus-one) for a softer ride or winter setup. Both stay inside the Âą3% diameter tolerance that ABS and TPMS systems expect.
Vehicle compatibility
22 vehicles in our database run the 225/40R18 tire size from the factory. Aftermarket fitment depends on rim width, offset, and clearance â match these specs to your wheel before purchasing tires.
Vehicles Using 225/40R18
Acura ILX
Years: 2013 - 2022
Alfa Romeo Giulietta
Years: 2010 - 2020
Audi A3
Years: 2003 - 2026
Audi S3
Years: 2006 - 2026
BMW 1 Series
Years: 2011 - 2026
BMW 2 Series
Years: 2014 - 2021
BMW 3 Series
Years: 2005 - 2013
BMW Z4
Years: 2009 - 2016
Kia Forte
Years: 2019 - 2026
Mercedes-Benz A-Class
Years: 2013 - 2018
Mercedes-Benz CLA
Years: 2014 - 2019
Mercedes-Benz SLK
Years: 2012 - 2015
Mini Cooper
Years: 2024 - 2026
Opel Astra
Years: 2015 - 2026
Peugeot 308
Years: 2021 - 2026
Seat Leon
Years: 2020 - 2026
Skoda Octavia
Years: 2013 - 2020
Subaru Impreza
Years: 2017 - 2023
Toyota Corolla
Years: 2018 - 2026
Toyota Yaris
Years: 2020 - 2026
Vauxhall Astra
Years: 2015 - 2026
Volkswagen Golf
Years: 1997 - 2012