What is the diameter of a P245/40R18 tire?

A P245/40R18 tire has an overall diameter of 25.72 inches (653.3mm).

How many revolutions per mile does a P245/40R18 tire make?

A P245/40R18 tire makes approximately 784 revolutions per mile.

What rim width is recommended for P245/40R18 tires?

The recommended wheel rim width for a P245/40R18 tire is 6.1" - 8.6".

P245/40R18

Passenger / P-Metric

Factory Specs, Physical Dimensions & Compatible Vehicle Applications

Factory Spec Overview

The P245/40R18 tire size features an overall diameter of 25.72 inches, a section width of 9.6 inches (245mm), and rotates 784 times per mile. It is a standard factory tire fitment on 133+ vehicle models including Audi A5.

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Physical Dimensions & Specs

Overall Diameter

25.72"

653.3 mm

Section Width

245 mm

9.65" wide

Sidewall Height

3.86"

98.0 mm (40% aspect)

Revolutions / Mile

784

Circumference: 80.79"

Rim Diameter

18"

Wheel size

Recommended Rim Width

6.1" - 8.6"

Optimal rim width range

Speedometer & Alternate Size Calculator

Testing an alternate size for your vehicle? Compare P245/40R18 against any proposed tire size below:

Popular Comparisons:

Tire 1 (Stock / Base)245/40R18

Section Width (mm)

Aspect Ratio (%)

Rim Diameter (in)

Wheel Width (in)

Offset ET (mm)

Overall Height:25.7"

Sidewall:3.9"

Revs/Mile:784

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

+15.0%At 60 mph reading, actual speed is 69.0 mph

Indicated	Actual Speed	Diff
20 mph	23.0 mph	+3.0 mph
30 mph	34.5 mph	+4.5 mph
45 mph	51.8 mph	+6.8 mph
60 mph	69.0 mph	+9.0 mph
75 mph	86.3 mph	+11.3 mph
90 mph	103.5 mph	+13.5 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:+1.93" ground clearance

Vehicles That Fit P245/40R18 (133+ Models)

Factory standard and optional vehicle fitments utilizing P245/40R18 tires:

Year	Make & Model	Trim / Variant	Lookup Specs
2008	Audi A5	Automatic	View 2008 A5 ›
2008	Audi A5	Standard	View 2008 A5 ›
2009	Audi A5	Automatic	View 2009 A5 ›
2009	Audi A5	Standard	View 2009 A5 ›
2010	Audi A5	2.0T Quattro, 2D Convertible, Standard	View 2010 A5 ›
2010	Audi A5	2.0T Quattro, 2D Coupe, Automatic	View 2010 A5 ›
2010	Audi A5	2.0T Quattro, 2D Convertible, Automatic	View 2010 A5 ›
2010	Audi A5	2.0T Quattro, 2D Coupe, Standard	View 2010 A5 ›
2010	Audi A5	2.0T, Automatic	View 2010 A5 ›
2010	Audi A5	2.0T, Standard	View 2010 A5 ›
2010	Audi A5	3.2 Quattro	View 2010 A5 ›
2011	Audi A5	2.0T	View 2011 A5 ›
2011	Audi A5	2.0T Quattro, 2D Coupe, Standard	View 2011 A5 ›
2011	Audi A5	2.0T Quattro, 2D Convertible	View 2011 A5 ›
2011	Audi A5	2.0T Quattro, 2D Coupe, Automatic	View 2011 A5 ›
2012	Audi A5	2.0T	View 2012 A5 ›
2012	Audi A5	2.0T Quattro, 2D Coupe, Standard Trans	View 2012 A5 ›
2012	Audi A5	2.0T Quattro, 2D Convertible	View 2012 A5 ›
2012	Audi A5	2.0T Quattro, 2D Coupe, Automatic Trans	View 2012 A5 ›
2013	Audi A5	Premium Plus Quattro, 2D Convertible, Eng CD CAEB	View 2013 A5 ›
2013	Audi A5	Premium Plus Quattro, 2D Convertible, Eng CD CPMA	View 2013 A5 ›
2013	Audi A5	Premium Plus Quattro, 2D Coupe, Eng CD CAEB, Automatic Trans	View 2013 A5 ›
2013	Audi A5	Premium Plus Quattro, 2D Coupe, Eng CD CAEB, Standard Trans	View 2013 A5 ›
2013	Audi A5	Premium Plus Quattro, 2D Coupe, Eng CD CPMA, Automatic Trans	View 2013 A5 ›
2013	Audi A5	Premium Plus Quattro, 2D Coupe, Eng CD CPMA, Standard Trans	View 2013 A5 ›
2013	Audi A5	Premium Plus, Eng CD CAEB	View 2013 A5 ›
2013	Audi A5	Premium Quattro, 2D Convertible, Eng CD CAEB	View 2013 A5 ›
2013	Audi A5	Premium Quattro, 2D Convertible, Eng CD CPMA	View 2013 A5 ›
2013	Audi A5	Premium Quattro, 2D Coupe, Eng CD CAEB, Automatic Trans	View 2013 A5 ›
2013	Audi A5	Premium Quattro, 2D Coupe, Eng CD CAEB, Standard Trans	View 2013 A5 ›
2013	Audi A5	Premium Quattro, 2D Coupe, Eng CD CPMA, Automatic Trans	View 2013 A5 ›
2013	Audi A5	Premium Quattro, 2D Coupe, Eng CD CPMA, Standard Trans	View 2013 A5 ›
2013	Audi A5	Premium, Eng CD CAEB	View 2013 A5 ›
2013	Audi A5	Prestige Quattro, 2D Convertible, Eng CD CAEB	View 2013 A5 ›
2013	Audi A5	Prestige Quattro, 2D Convertible, Eng CD CPMA	View 2013 A5 ›
2013	Audi A5	Prestige Quattro, 2D Coupe, Eng CD CAEB, Automatic Trans	View 2013 A5 ›
2013	Audi A5	Prestige Quattro, 2D Coupe, Eng CD CAEB, Standard Trans	View 2013 A5 ›
2013	Audi A5	Prestige Quattro, 2D Coupe, Eng CD CPMA, Automatic Trans	View 2013 A5 ›
2013	Audi A5	Prestige Quattro, 2D Coupe, Eng CD CPMA, Standard Trans	View 2013 A5 ›
2013	Audi A5	Prestige, Eng CD CAEB	View 2013 A5 ›
2014	Cadillac CTS	Performance, 4D Sedan, 2.0L Eng VIN X, AWD	View 2014 CTS ›
2014	Cadillac CTS	Performance, 4D Sedan, 2.0L Eng VIN X, RWD	View 2014 CTS ›
2014	Cadillac CTS	Performance, 4D Sedan, 3.6L Eng VIN 3, AWD	View 2014 CTS ›
2014	Cadillac CTS	Performance, 4D Sedan, 3.6L Eng VIN 3, RWD	View 2014 CTS ›
2014	Cadillac CTS	Premium, 4D Sedan, 2.0L Eng VIN X, AWD	View 2014 CTS ›
2014	Cadillac CTS	Premium, 4D Sedan, 2.0L Eng VIN X, RWD	View 2014 CTS ›
2014	Cadillac CTS	Premium, 4D Sedan, 3.6L Eng VIN 3, AWD	View 2014 CTS ›
2014	Cadillac CTS	Premium, 4D Sedan, 3.6L Eng VIN 3, RWD	View 2014 CTS ›
2015	Cadillac CTS	Performance, 2.0L Eng VIN X, AWD	View 2015 CTS ›
2015	Cadillac CTS	Performance, 2.0L Eng VIN X, RWD	View 2015 CTS ›
2015	Cadillac CTS	Performance, 3.6L Eng VIN 3, AWD	View 2015 CTS ›
2015	Cadillac CTS	Performance, 3.6L Eng VIN 3, RWD	View 2015 CTS ›
2015	Cadillac CTS	Premium, 2.0L Eng VIN X, AWD	View 2015 CTS ›
2015	Cadillac CTS	Premium, 2.0L Eng VIN X, RWD	View 2015 CTS ›
2015	Cadillac CTS	Premium, 3.6L Eng VIN 3, AWD	View 2015 CTS ›
2015	Cadillac CTS	Premium, 3.6L Eng VIN 3, RWD	View 2015 CTS ›
2016	Cadillac CTS	Performance, 2.0L Eng VIN X, AWD	View 2016 CTS ›
2016	Cadillac CTS	Performance, 2.0L Eng VIN X, RWD	View 2016 CTS ›
2016	Cadillac CTS	Performance, 3.6L Eng VIN S, AWD	View 2016 CTS ›
2016	Cadillac CTS	Performance, 3.6L Eng VIN S, RWD	View 2016 CTS ›
2016	Cadillac CTS	Premium, 2.0L Eng VIN X, AWD	View 2016 CTS ›
2016	Cadillac CTS	Premium, 2.0L Eng VIN X, RWD	View 2016 CTS ›
2016	Cadillac CTS	Premium, 3.6L Eng VIN S, AWD	View 2016 CTS ›
2016	Cadillac CTS	Premium, 3.6L Eng VIN S, RWD	View 2016 CTS ›
2017	Cadillac CTS	Premium Luxury, AWD	View 2017 CTS ›
2017	Cadillac CTS	Premium Luxury, RWD	View 2017 CTS ›
2018	Cadillac CTS	Premium Luxury, AWD	View 2018 CTS ›
2018	Cadillac CTS	Premium Luxury, RWD	View 2018 CTS ›
2019	Cadillac CTS	Premium Luxury, AWD	View 2019 CTS ›
2019	Cadillac CTS	Premium Luxury, RWD	View 2019 CTS ›
2005	Chevrolet Corvette	2D Convertible, Standard	View 2005 Corvette ›
2005	Chevrolet Corvette	2D Convertible, Automatic	View 2005 Corvette ›
2005	Chevrolet Corvette	2D Coupe, Automatic	View 2005 Corvette ›
2005	Chevrolet Corvette	2D Coupe, Standard	View 2005 Corvette ›
2006	Chevrolet Corvette	Base, 2D Convertible, Automatic	View 2006 Corvette ›
2006	Chevrolet Corvette	Base, 2D Convertible, Standard	View 2006 Corvette ›
2006	Chevrolet Corvette	Base, 2D Coupe, Automatic	View 2006 Corvette ›
2006	Chevrolet Corvette	Base, 2D Coupe, Standard	View 2006 Corvette ›
2007	Chevrolet Corvette	Base, 2D Convertible, Automatic	View 2007 Corvette ›
2007	Chevrolet Corvette	Base, 2D Convertible, Standard	View 2007 Corvette ›
2007	Chevrolet Corvette	Base, 2D Coupe, Automatic	View 2007 Corvette ›
2007	Chevrolet Corvette	Base, 2D Coupe, Standard	View 2007 Corvette ›
2008	Chevrolet Corvette	Base, 2D Convertible, Automatic	View 2008 Corvette ›
2008	Chevrolet Corvette	Base, 2D Convertible, Standard	View 2008 Corvette ›
2008	Chevrolet Corvette	Base, 2D Coupe, Automatic	View 2008 Corvette ›
2008	Chevrolet Corvette	Base, 2D Coupe, Standard	View 2008 Corvette ›
2008	Chevrolet Corvette	Z06	View 2008 Corvette ›
2009	Chevrolet Corvette	Base, 2D Convertible, Automatic	View 2009 Corvette ›
2009	Chevrolet Corvette	Base, 2D Convertible, Standard	View 2009 Corvette ›
2009	Chevrolet Corvette	Base, 2D Coupe, Automatic	View 2009 Corvette ›
2009	Chevrolet Corvette	Base, 2D Coupe, Standard	View 2009 Corvette ›
2010	Chevrolet Corvette	Base, 2D Convertible, Automatic	View 2010 Corvette ›
2010	Chevrolet Corvette	Base, 2D Convertible, Standard	View 2010 Corvette ›
2010	Chevrolet Corvette	Base, 2D Coupe, Automatic	View 2010 Corvette ›
2010	Chevrolet Corvette	Base, 2D Coupe, Standard	View 2010 Corvette ›
2011	Chevrolet Corvette	Base, 2D Convertible, Automatic	View 2011 Corvette ›
2011	Chevrolet Corvette	Base, 2D Convertible, Standard	View 2011 Corvette ›
2011	Chevrolet Corvette	Base, 2D Coupe, Automatic	View 2011 Corvette ›
2011	Chevrolet Corvette	Base, 2D Coupe, Standard	View 2011 Corvette ›
2012	Chevrolet Corvette	Base, 2D Convertible, Automatic Trans	View 2012 Corvette ›
2012	Chevrolet Corvette	Base, 2D Convertible, Standard Trans, Trans Mfr CD 6L85M/MM6	View 2012 Corvette ›
2012	Chevrolet Corvette	Base, 2D Convertible, Standard Trans, Trans Mfr CD 6L90M/MZ6	View 2012 Corvette ›
2012	Chevrolet Corvette	Base, 2D Coupe, Automatic Trans	View 2012 Corvette ›
2012	Chevrolet Corvette	Base, 2D Coupe, Standard Trans, Trans Mfr CD 6L85M/MM6	View 2012 Corvette ›
2012	Chevrolet Corvette	Base, 2D Coupe, Standard Trans, Trans Mfr CD 6L90M/MZ6	View 2012 Corvette ›
2013	Chevrolet Corvette	Base, 2D Convertible, Automatic Trans	View 2013 Corvette ›
2013	Chevrolet Corvette	Base, 2D Convertible, Standard Trans, Trans Mfr CD 6L85M/MM6	View 2013 Corvette ›
2013	Chevrolet Corvette	Base, 2D Convertible, Standard Trans, Trans Mfr CD 6L90M/MZ6	View 2013 Corvette ›
2013	Chevrolet Corvette	Base, 2D Coupe, Automatic Trans	View 2013 Corvette ›
2013	Chevrolet Corvette	Base, 2D Coupe, Standard Trans, Trans Mfr CD 6L85M/MM6	View 2013 Corvette ›
2013	Chevrolet Corvette	Base, 2D Coupe, Standard Trans, Trans Mfr CD 6L90M/MZ6	View 2013 Corvette ›
2014	Chevrolet Corvette	2D Convertible, Automatic Trans	View 2014 Corvette ›
2014	Chevrolet Corvette	2D Convertible, Standard Trans	View 2014 Corvette ›
2014	Chevrolet Corvette	2D Coupe, Automatic Trans	View 2014 Corvette ›
2014	Chevrolet Corvette	2D Coupe, Standard Trans	View 2014 Corvette ›
2015	Chevrolet Corvette	Stingray, 2D Convertible, Automatic Trans	View 2015 Corvette ›
2015	Chevrolet Corvette	Stingray, 2D Convertible, Standard Trans	View 2015 Corvette ›
2015	Chevrolet Corvette	Stingray, 2D Coupe, Automatic Trans	View 2015 Corvette ›
2015	Chevrolet Corvette	Stingray, 2D Coupe, Standard Trans	View 2015 Corvette ›
2016	Chevrolet Corvette	Stingray, 2D Convertible, Automatic Trans	View 2016 Corvette ›
2016	Chevrolet Corvette	Stingray, 2D Convertible, Standard Trans	View 2016 Corvette ›
2016	Chevrolet Corvette	Stingray, 2D Coupe, Automatic Trans	View 2016 Corvette ›
2016	Chevrolet Corvette	Stingray, 2D Coupe, Standard Trans	View 2016 Corvette ›
2017	Chevrolet Corvette	Stingray, 2D Coupe, Standard Trans	View 2017 Corvette ›
2017	Chevrolet Corvette	Stingray, 2D Coupe, Automatic Trans	View 2017 Corvette ›
2017	Chevrolet Corvette	Stingray, 2D Convertible, Automatic Trans	View 2017 Corvette ›
2017	Chevrolet Corvette	Stingray, 2D Convertible, Standard Trans	View 2017 Corvette ›
2007	Lexus GS 450h	GS 450h	View 2007 GS 450h ›
2008	Lexus GS 450h	GS 450h	View 2008 GS 450h ›
2009	Lexus GS 450h	GS 450h	View 2009 GS 450h ›
2010	Lexus GS 450h	GS 450h	View 2010 GS 450h ›
2011	Lexus GS 450h	GS 450h	View 2011 GS 450h ›
2011	Lexus GS 460	GS 460	View 2011 GS 460 ›