What is the diameter of a 235/40R18 tire?

A 235/40R18 tire has an overall diameter of 25.4 inches (645.2mm).

How many revolutions per mile does a 235/40R18 tire make?

A 235/40R18 tire makes approximately 794 revolutions per mile.

What rim width is recommended for 235/40R18 tires?

The recommended wheel rim width for a 235/40R18 tire is 5.9" - 8.2".

235/40R18

Standard Metric

Factory Specs, Physical Dimensions & Compatible Vehicle Applications

Factory Spec Overview

The 235/40R18 tire size features an overall diameter of 25.4 inches, a section width of 9.3 inches (235mm), and rotates 794 times per mile. It is a standard factory tire fitment on 150+ vehicle models including Acura TL.

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Physical Dimensions & Specs

Overall Diameter

25.4"

645.2 mm

Section Width

235 mm

9.25" wide

Sidewall Height

3.7"

94.0 mm (40% aspect)

Revolutions / Mile

794

Circumference: 79.8"

Rim Diameter

18"

Wheel size

Recommended Rim Width

5.9" - 8.2"

Optimal rim width range

Speedometer & Alternate Size Calculator

Testing an alternate size for your vehicle? Compare 235/40R18 against any proposed tire size below:

Popular Comparisons:

Tire 1 (Stock / Base)235/40R18

Section Width (mm)

Aspect Ratio (%)

Rim Diameter (in)

Wheel Width (in)

Offset ET (mm)

Overall Height:25.4"

Sidewall:3.7"

Revs/Mile:794

Tire 2 (New / Compare)245/60R18

Section Width (mm)

Aspect Ratio (%)

Rim Diameter (in)

Wheel Width (in)

Offset ET (mm)

Overall Height:29.6"

Sidewall:5.8"

Revs/Mile:682

Visual Tire & Wheel Comparison

Speedometer Variance

+16.4%At 60 mph reading, actual speed is 69.9 mph

Indicated	Actual Speed	Diff
20 mph	23.3 mph	+3.3 mph
30 mph	34.9 mph	+4.9 mph
45 mph	52.4 mph	+7.4 mph
60 mph	69.9 mph	+9.9 mph
75 mph	87.3 mph	+12.3 mph
90 mph	104.8 mph	+14.8 mph

Fender & Suspension Clearance

Fitment Status: MODERATE RISK

Flush fitment. Extends 17.7mm outwards. Check wheel arch clearance under full suspension compression.

Inner Strut Space:7.7mm LESS clearance

Outer Fender Push:Extends 17.7mm further out

Ride Height Delta:+2.09" ground clearance

Vehicles That Fit 235/40R18 (150+ Models)

Factory standard and optional vehicle fitments utilizing 235/40R18 tires:

Year	Make & Model	Trim / Variant	Lookup Specs
2005	Acura TL	Standard	View 2005 TL ›
2005	Acura TL	Automatic	View 2005 TL ›
2007	Acura TL	Type S, Automatic	View 2007 TL ›
2007	Acura TL	Type S, Standard	View 2007 TL ›
2008	Acura TL	Type S, Automatic	View 2008 TL ›
2008	Acura TL	Type S, Standard	View 2008 TL ›
2023	Acura Integra	A-Spec, Automatic CVT Trans	View 2023 Integra ›
2023	Acura Integra	A-Spec, Standard Trans	View 2023 Integra ›
2024	Acura Integra	A-Spec, Standard Trans	View 2024 Integra ›
2024	Acura Integra	A-Spec, Automatic CVT Trans	View 2024 Integra ›
2025	Acura Integra	A-Spec, Standard Trans	View 2025 Integra ›
2025	Acura Integra	A-Spec, Automatic CVT Trans	View 2025 Integra ›
2015	Alfa Romeo 4C	Base	View 2015 4C ›
2015	Alfa Romeo 4C	Spider	View 2015 4C ›
2016	Alfa Romeo 4C	Base	View 2016 4C ›
2016	Alfa Romeo 4C	Spider	View 2016 4C ›
2017	Alfa Romeo 4C	Spider	View 2017 4C ›
2017	Alfa Romeo 4C	Base	View 2017 4C ›
2018	Alfa Romeo 4C	Base	View 2018 4C ›
2018	Alfa Romeo 4C	Spider	View 2018 4C ›
2019	Alfa Romeo 4C	4C	View 2019 4C ›
2020	Alfa Romeo 4C	Spider	View 2020 4C ›
2020	Alfa Romeo 4C	Spider Italia	View 2020 4C ›
2004	Audi A6	Quattro, 2.7 D, Automatic	View 2004 A6 ›
2004	Audi A6	Quattro, 2.7 D, Standard	View 2004 A6 ›
2004	Audi S4	Avant Quattro, Automatic	View 2004 S4 ›
2004	Audi S4	Avant Quattro, Standard	View 2004 S4 ›
2004	Audi S4	Quattro, 2D Convertible, Automatic	View 2004 S4 ›
2004	Audi S4	Quattro, 2D Convertible, Standard	View 2004 S4 ›
2004	Audi S4	Quattro, 4D Sedan, Automatic	View 2004 S4 ›
2004	Audi S4	Quattro, 4D Sedan, Standard	View 2004 S4 ›
2005	Audi S4	Avant Quattro, Automatic	View 2005 S4 ›
2005	Audi S4	Avant Quattro, Standard	View 2005 S4 ›
2005	Audi S4	Quattro, 2D Convertible, Automatic	View 2005 S4 ›
2005	Audi S4	Quattro, 2D Convertible, Standard	View 2005 S4 ›
2005	Audi S4	Quattro, 4D Sedan, Automatic	View 2005 S4 ›
2005	Audi S4	Quattro, 4D Sedan, Standard	View 2005 S4 ›
2006	Audi A4	Base, 4D Sedan, 2.0 F, Automatic CVT	View 2006 A4 ›
2006	Audi A4	Base, 4D Sedan, 2.0 F, Standard	View 2006 A4 ›
2006	Audi S4	Avant Quattro, Automatic	View 2006 S4 ›
2006	Audi S4	Avant Quattro, Standard	View 2006 S4 ›
2006	Audi S4	Quattro, 2D Convertible, Automatic	View 2006 S4 ›
2006	Audi S4	Quattro, 4D Sedan, Automatic	View 2006 S4 ›
2006	Audi S4	Quattro, 2D Convertible, Standard	View 2006 S4 ›
2006	Audi S4	Quattro, 4D Sedan, Standard	View 2006 S4 ›
2007	Audi A4	Base, 2D Convertible	View 2007 A4 ›
2007	Audi A4	Base, 4D Sedan, 2.0 F, BWT, Automatic CVT	View 2007 A4 ›
2007	Audi A4	Base, 4D Sedan, 2.0 F, BWT, Standard	View 2007 A4 ›
2007	Audi A4	Base, 4D Sedan, 3.2 H	View 2007 A4 ›
2007	Audi S4	Avant Quattro, Automatic	View 2007 S4 ›
2007	Audi S4	Avant Quattro, Standard	View 2007 S4 ›
2007	Audi S4	Quattro, 2D Convertible, Automatic	View 2007 S4 ›
2007	Audi S4	Quattro, 2D Convertible, Standard	View 2007 S4 ›
2007	Audi S4	Quattro, 4D Sedan, Automatic	View 2007 S4 ›
2007	Audi S4	Quattro, 4D Sedan, Standard	View 2007 S4 ›
2008	Audi A4	Base, 2D Convertible	View 2008 A4 ›
2008	Audi A4	Base, 4D Sedan, 2.0 F, Automatic CVT	View 2008 A4 ›
2008	Audi A4	Base, 4D Sedan, 2.0 F, Standard	View 2008 A4 ›
2008	Audi A4	Base, 4D Sedan, 3.2 H	View 2008 A4 ›
2008	Audi S4	Avant Quattro, Automatic	View 2008 S4 ›
2008	Audi S4	Avant Quattro, Standard	View 2008 S4 ›
2008	Audi S4	Quattro, 2D Convertible, Automatic	View 2008 S4 ›
2008	Audi S4	Quattro, 2D Convertible, Standard	View 2008 S4 ›
2008	Audi S4	Quattro, 4D Sedan, Automatic	View 2008 S4 ›
2008	Audi S4	Quattro, 4D Sedan, Standard	View 2008 S4 ›
2009	Audi S4	Automatic	View 2009 S4 ›
2009	Audi S4	Standard	View 2009 S4 ›
2020	Cadillac CT4	Premium Luxury, 2.0L Eng VIN K, RWD	View 2020 CT4 ›
2020	Cadillac CT4	Premium Luxury, 2.7L Eng VIN L, 4WD	View 2020 CT4 ›
2020	Cadillac CT4	Premium Luxury, 2.0L Eng VIN K, 4WD	View 2020 CT4 ›
2020	Cadillac CT4	Sport, RWD	View 2020 CT4 ›
2020	Cadillac CT4	Premium Luxury, 2.7L Eng VIN L, RWD	View 2020 CT4 ›
2020	Cadillac CT4	V, 4WD	View 2020 CT4 ›
2020	Cadillac CT4	Sport, 4WD	View 2020 CT4 ›
2020	Cadillac CT4	V, RWD	View 2020 CT4 ›
2021	Cadillac CT4	Premium Luxury, 2.0L Eng VIN K, 4WD	View 2021 CT4 ›
2021	Cadillac CT4	Premium Luxury, 2.0L Eng VIN K, RWD	View 2021 CT4 ›
2021	Cadillac CT4	Premium Luxury, 2.7L Eng VIN L, 4WD	View 2021 CT4 ›
2021	Cadillac CT4	Premium Luxury, 2.7L Eng VIN L, RWD	View 2021 CT4 ›
2021	Cadillac CT4	Sport, 4WD	View 2021 CT4 ›
2021	Cadillac CT4	V, 4WD	View 2021 CT4 ›
2021	Cadillac CT4	Sport, RWD	View 2021 CT4 ›
2021	Cadillac CT4	V, RWD	View 2021 CT4 ›
2022	Cadillac CT4	Premium Luxury, 2.0L Eng VIN K, 4WD	View 2022 CT4 ›
2022	Cadillac CT4	Premium Luxury, 2.0L Eng VIN K, RWD	View 2022 CT4 ›
2022	Cadillac CT4	Premium Luxury, 2.7L Eng VIN L, RWD	View 2022 CT4 ›
2022	Cadillac CT4	Sport, 4WD	View 2022 CT4 ›
2022	Cadillac CT4	Sport, RWD	View 2022 CT4 ›
2022	Cadillac CT4	Premium Luxury, 2.7L Eng VIN L, 4WD	View 2022 CT4 ›
2022	Cadillac CT4	V, 4WD	View 2022 CT4 ›
2022	Cadillac CT4	V, RWD	View 2022 CT4 ›
2023	Cadillac CT4	Premium Luxury, 2.0L Eng VIN K, 4WD	View 2023 CT4 ›
2023	Cadillac CT4	Premium Luxury, 2.0L Eng VIN K, RWD	View 2023 CT4 ›
2023	Cadillac CT4	Premium Luxury, 2.7L Eng VIN L, RWD	View 2023 CT4 ›
2023	Cadillac CT4	Premium Luxury, 2.7L Eng VIN L, 4WD	View 2023 CT4 ›
2023	Cadillac CT4	Sport, RWD	View 2023 CT4 ›
2023	Cadillac CT4	V, RWD	View 2023 CT4 ›
2023	Cadillac CT4	Sport, 4WD	View 2023 CT4 ›
2023	Cadillac CT4	V, 4WD	View 2023 CT4 ›
2024	Cadillac CT4	Premium Luxury, 2.0L Eng VIN K, 4WD	View 2024 CT4 ›
2024	Cadillac CT4	Premium Luxury, 2.7L Eng VIN L, 4WD	View 2024 CT4 ›
2024	Cadillac CT4	Premium Luxury, 2.0L Eng VIN K, RWD	View 2024 CT4 ›
2024	Cadillac CT4	Premium Luxury, 2.7L Eng VIN L, RWD	View 2024 CT4 ›
2024	Cadillac CT4	Sport, 4WD	View 2024 CT4 ›
2024	Cadillac CT4	Sport, RWD	View 2024 CT4 ›
2024	Cadillac CT4	V, RWD	View 2024 CT4 ›
2024	Cadillac CT4	V, 4WD	View 2024 CT4 ›
2025	Cadillac CT4	Premium Luxury, 2.0L Eng VIN K, 4WD	View 2025 CT4 ›
2025	Cadillac CT4	Premium Luxury, 2.0L Eng VIN K, RWD	View 2025 CT4 ›
2025	Cadillac CT4	Premium Luxury, 2.7L Eng VIN L, RWD	View 2025 CT4 ›
2025	Cadillac CT4	Premium Luxury, 2.7L Eng VIN L, 4WD	View 2025 CT4 ›
2025	Cadillac CT4	Sport, 4WD	View 2025 CT4 ›
2025	Cadillac CT4	Sport, RWD	View 2025 CT4 ›
2025	Cadillac CT4	V, RWD	View 2025 CT4 ›
2025	Cadillac CT4	V, 4WD	View 2025 CT4 ›
2012	Ford Focus	Titanium, 4D Hatchback, Automatic DCT Trans, Gas	View 2012 Focus ›
2012	Ford Focus	Titanium, 4D Hatchback, Automatic DCT Trans, Gas/Ethanol	View 2012 Focus ›
2012	Ford Focus	Titanium, 4D Hatchback, Standard Trans, Gas	View 2012 Focus ›
2012	Ford Focus	Titanium, 4D Sedan, Automatic DCT Trans, Gas/Ethanol	View 2012 Focus ›
2012	Ford Focus	Titanium, 4D Hatchback, Standard Trans, Gas/Ethanol	View 2012 Focus ›
2012	Ford Focus	Titanium, 4D Sedan, Automatic DCT Trans, Gas	View 2012 Focus ›
2012	Ford Focus	Titanium, 4D Sedan, Standard Trans, Gas	View 2012 Focus ›
2012	Ford Focus	Titanium, 4D Sedan, Standard Trans, Gas/Ethanol	View 2012 Focus ›
2013	Ford Focus	ST	View 2013 Focus ›
2013	Ford Focus	Titanium, 4D Hatchback, Automatic DCT Trans, Gas	View 2013 Focus ›
2013	Ford Focus	Titanium, 4D Hatchback, Automatic DCT Trans, Gas/Ethanol	View 2013 Focus ›
2013	Ford Focus	Titanium, 4D Hatchback, Standard Trans, Gas	View 2013 Focus ›
2013	Ford Focus	Titanium, 4D Hatchback, Standard Trans, Gas/Ethanol	View 2013 Focus ›
2013	Ford Focus	Titanium, 4D Sedan, Automatic DCT Trans, Gas	View 2013 Focus ›
2013	Ford Focus	Titanium, 4D Sedan, Automatic DCT Trans, Gas/Ethanol	View 2013 Focus ›
2013	Ford Focus	Titanium, 4D Sedan, Standard Trans, Gas	View 2013 Focus ›
2013	Ford Focus	Titanium, 4D Sedan, Standard Trans, Gas/Ethanol	View 2013 Focus ›
2014	Ford Focus	Titanium, 4D Hatchback, Automatic DCT Trans, Gas	View 2014 Focus ›
2014	Ford Focus	ST	View 2014 Focus ›
2014	Ford Focus	Titanium, 4D Hatchback, Automatic DCT Trans, Gas/Ethanol	View 2014 Focus ›
2014	Ford Focus	Titanium, 4D Hatchback, Standard Trans, Gas	View 2014 Focus ›
2014	Ford Focus	Titanium, 4D Hatchback, Standard Trans, Gas/Ethanol	View 2014 Focus ›
2014	Ford Focus	Titanium, 4D Sedan, Automatic DCT Trans, Gas	View 2014 Focus ›
2014	Ford Focus	Titanium, 4D Sedan, Automatic DCT Trans, Gas/Ethanol	View 2014 Focus ›
2014	Ford Focus	Titanium, 4D Sedan, Standard Trans, Gas	View 2014 Focus ›
2014	Ford Focus	Titanium, 4D Sedan, Standard Trans, Gas/Ethanol	View 2014 Focus ›
2015	Ford Focus	ST	View 2015 Focus ›
2015	Ford Focus	Titanium, 4D Hatchback, Automatic DCT Trans, Gas	View 2015 Focus ›
2015	Ford Focus	Titanium, 4D Hatchback, Automatic DCT Trans, Gas/Ethanol	View 2015 Focus ›
2015	Ford Focus	Titanium, 4D Hatchback, Standard Trans, Gas	View 2015 Focus ›
2015	Ford Focus	Titanium, 4D Hatchback, Standard Trans, Gas/Ethanol	View 2015 Focus ›
2015	Ford Focus	Titanium, 4D Sedan, Automatic DCT Trans, Gas	View 2015 Focus ›
2015	Ford Focus	Titanium, 4D Sedan, Automatic DCT Trans, Gas/Ethanol	View 2015 Focus ›
2015	Ford Focus	Titanium, 4D Sedan, Standard Trans, Gas	View 2015 Focus ›
2015	Ford Focus	Titanium, 4D Sedan, Standard Trans, Gas/Ethanol	View 2015 Focus ›