What is the diameter of a 255/40R20 tire?

A 255/40R20 tire has an overall diameter of 28.03 inches (712.0mm).

How many revolutions per mile does a 255/40R20 tire make?

A 255/40R20 tire makes approximately 719 revolutions per mile.

What rim width is recommended for 255/40R20 tires?

The recommended wheel rim width for a 255/40R20 tire is 6.4" - 8.9".

255/40R20

Standard Metric

Factory Specs, Physical Dimensions & Compatible Vehicle Applications

Factory Spec Overview

The 255/40R20 tire size features an overall diameter of 28.03 inches, a section width of 10.0 inches (255mm), and rotates 719 times per mile. It is a standard factory tire fitment on 150+ vehicle models including Audi Q3, Audi S7, Audi S6.

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Physical Dimensions & Specs

Overall Diameter

28.03"

712.0 mm

Section Width

255 mm

10.04" wide

Sidewall Height

4.02"

102.1 mm (40% aspect)

Revolutions / Mile

719

Circumference: 88.06"

Rim Diameter

20"

Wheel size

Recommended Rim Width

6.4" - 8.9"

Optimal rim width range

Speedometer & Alternate Size Calculator

Testing an alternate size for your vehicle? Compare 255/40R20 against any proposed tire size below:

Popular Comparisons:

Tire 1 (Stock / Base)255/40R20

Section Width (mm)

Aspect Ratio (%)

Rim Diameter (in)

Wheel Width (in)

Offset ET (mm)

Overall Height:28.0"

Sidewall:4.0"

Revs/Mile:719

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

+5.5%At 60 mph reading, actual speed is 63.3 mph

Indicated	Actual Speed	Diff
20 mph	21.1 mph	+1.1 mph
30 mph	31.7 mph	+1.7 mph
45 mph	47.5 mph	+2.5 mph
60 mph	63.3 mph	+3.3 mph
75 mph	79.1 mph	+4.1 mph
90 mph	95.0 mph	+5.0 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:+0.77" ground clearance

Vehicles That Fit 255/40R20 (150+ Models)

Factory standard and optional vehicle fitments utilizing 255/40R20 tires:

Year	Make & Model	Trim / Variant	Lookup Specs
2019	Audi Q3	Prestige S-Line	View 2019 Q3 ›
2020	Audi S7	Premium Plus	View 2020 S7 ›
2020	Audi S6	Prestige	View 2020 S6 ›
2020	Audi S7	Prestige	View 2020 S7 ›
2020	Audi S6	Premium Plus	View 2020 S6 ›
2021	Audi A7 Quattro	Premium	View 2021 A7 Quattro ›
2021	Audi A7 Quattro	Premium Plus	View 2021 A7 Quattro ›
2021	Audi A7 Quattro	Prestige	View 2021 A7 Quattro ›
2021	Audi A7 e Quattro	Premium Plus	View 2021 A7 e Quattro ›
2021	Audi A7 e Quattro	Prestige	View 2021 A7 e Quattro ›
2022	Audi A7 Quattro	Premium	View 2022 A7 Quattro ›
2022	Audi A7 Quattro	Premium Plus	View 2022 A7 Quattro ›
2022	Audi A7 Quattro	Prestige	View 2022 A7 Quattro ›
2022	Audi A7 e Quattro	Premium Plus	View 2022 A7 e Quattro ›
2022	Audi A7 e Quattro	Prestige	View 2022 A7 e Quattro ›
2023	Audi A7 Quattro	Premium	View 2023 A7 Quattro ›
2023	Audi A7 Quattro	Premium Plus	View 2023 A7 Quattro ›
2023	Audi A7 Quattro	Prestige	View 2023 A7 Quattro ›
2024	Audi A6 Quattro	Prestige	View 2024 A6 Quattro ›
2024	Audi A6 Quattro	Premium, 2.0L Eng VIN 3	View 2024 A6 Quattro ›
2024	Audi A7 Quattro	Premium Plus	View 2024 A7 Quattro ›
2024	Audi A6 Quattro	Premium Plus, 2.0L Eng VIN 3	View 2024 A6 Quattro ›
2024	Audi A7 Quattro	Prestige	View 2024 A7 Quattro ›
2024	Audi A7 Quattro	Premium	View 2024 A7 Quattro ›
2025	Audi A6 Quattro	Premium Plus, 2.0L Eng VIN 3	View 2025 A6 Quattro ›
2025	Audi A6 Quattro	Premium, 2.0L Eng VIN 3	View 2025 A6 Quattro ›
2025	Audi A7 Quattro	Prestige	View 2025 A7 Quattro ›
2025	Audi A7 Quattro	Premium	View 2025 A7 Quattro ›
2025	Audi A7 Quattro	Premium Plus	View 2025 A7 Quattro ›
2025	Audi A6 Quattro	Prestige	View 2025 A6 Quattro ›
2017	BMW Alpina B7 xDrive	Alpina B7 xDrive	View 2017 Alpina B7 xDrive ›
2018	BMW Alpina B7 xDrive	Alpina B7 xDrive	View 2018 Alpina B7 xDrive ›
2019	BMW Alpina B7 xDrive	Alpina B7 xDrive	View 2019 Alpina B7 xDrive ›
2020	BMW Alpina B7 xDrive	Alpina B7 xDrive	View 2020 Alpina B7 xDrive ›
2021	BMW Alpina B7 xDrive	Alpina B7 xDrive	View 2021 Alpina B7 xDrive ›
2022	BMW Alpina B7 xDrive	Alpina B7 xDrive	View 2022 Alpina B7 xDrive ›
2014	Mercedes-Benz S63 AMG	S63 AMG	View 2014 S63 AMG ›
2015	Mercedes-Benz S63 AMG	4D Sedan	View 2015 S63 AMG ›
2015	Mercedes-Benz S65 AMG	2D Coupe	View 2015 S65 AMG ›
2015	Mercedes-Benz S65 AMG	4D Sedan	View 2015 S65 AMG ›
2015	Mercedes-Benz S63 AMG	2D Coupe	View 2015 S63 AMG ›
2016	Mercedes-Benz S63 AMG	2D Coupe	View 2016 S63 AMG ›
2016	Mercedes-Benz S63 AMG	4D Sedan	View 2016 S63 AMG ›
2016	Mercedes-Benz S65 AMG	2D Coupe	View 2016 S65 AMG ›
2016	Mercedes-Benz S65 AMG	4D Sedan	View 2016 S65 AMG ›
2017	Mercedes-Benz S63 AMG	2D Convertible	View 2017 S63 AMG ›
2017	Mercedes-Benz S63 AMG	4D Sedan	View 2017 S63 AMG ›
2017	Mercedes-Benz S65 AMG	2D Convertible	View 2017 S65 AMG ›
2017	Mercedes-Benz S63 AMG	2D Coupe	View 2017 S63 AMG ›
2017	Mercedes-Benz S65 AMG	4D Sedan	View 2017 S65 AMG ›
2017	Mercedes-Benz S65 AMG	2D Coupe	View 2017 S65 AMG ›
2018	Mercedes-Benz S63 AMG	2D Convertible	View 2018 S63 AMG ›
2018	Mercedes-Benz S63 AMG	2D Coupe	View 2018 S63 AMG ›
2018	Mercedes-Benz S63 AMG	4D Sedan	View 2018 S63 AMG ›
2018	Mercedes-Benz S65 AMG	2D Convertible	View 2018 S65 AMG ›
2018	Mercedes-Benz S65 AMG	2D Coupe	View 2018 S65 AMG ›
2018	Mercedes-Benz S65 AMG	4D Sedan	View 2018 S65 AMG ›
2019	Mercedes-Benz S63 AMG	2D Convertible	View 2019 S63 AMG ›
2019	Mercedes-Benz S63 AMG	2D Coupe	View 2019 S63 AMG ›
2019	Mercedes-Benz S65 AMG	2D Convertible	View 2019 S65 AMG ›
2019	Mercedes-Benz S65 AMG	4D Sedan	View 2019 S65 AMG ›
2019	Mercedes-Benz S65 AMG	2D Coupe	View 2019 S65 AMG ›
2019	Mercedes-Benz S63 AMG	4D Sedan	View 2019 S63 AMG ›
2020	Mercedes-Benz S63 AMG	2D Coupe	View 2020 S63 AMG ›
2020	Mercedes-Benz S63 AMG	2D Convertible	View 2020 S63 AMG ›
2020	Mercedes-Benz S63 AMG	4D Sedan	View 2020 S63 AMG ›
2020	Mercedes-Benz S65 AMG	S65 AMG	View 2020 S65 AMG ›
2021	Mercedes-Benz S63 AMG	2D Convertible	View 2021 S63 AMG ›
2021	Mercedes-Benz S63 AMG	2D Coupe	View 2021 S63 AMG ›
2021	Mercedes-Benz Maybach S580	Maybach S580	View 2021 Maybach S580 ›
2022	Mercedes-Benz Maybach S580	Maybach S580	View 2022 Maybach S580 ›
2022	Mercedes-Benz Maybach S680	Maybach S680	View 2022 Maybach S680 ›
2023	Mercedes-Benz Maybach S580	Maybach S580	View 2023 Maybach S580 ›
2023	Mercedes-Benz Maybach S680	Maybach S680	View 2023 Maybach S680 ›
2024	Mercedes-Benz Maybach S580	Maybach S580	View 2024 Maybach S580 ›
2024	Mercedes-Benz Maybach S680	Maybach S680	View 2024 Maybach S680 ›
2025	Mercedes-Benz EQE350	EQE350	View 2025 EQE350 ›
2025	Mercedes-Benz EQE350+	EQE350+	View 2025 EQE350+ ›
2025	Mercedes-Benz EQE500	EQE500	View 2025 EQE500 ›
2025	Mercedes-Benz Maybach S580	Maybach S580	View 2025 Maybach S580 ›
2025	Mercedes-Benz Maybach S680	Maybach S680	View 2025 Maybach S680 ›
2009	Nissan GT-R	Base	View 2009 GT-R ›
2009	Nissan GT-R	Premium	View 2009 GT-R ›
2010	Nissan GT-R	Base	View 2010 GT-R ›
2010	Nissan GT-R	Premium	View 2010 GT-R ›
2011	Nissan GT-R	GT-R	View 2011 GT-R ›
2012	Nissan GT-R	Black Edition	View 2012 GT-R ›
2012	Nissan GT-R	Premium	View 2012 GT-R ›
2013	Nissan GT-R	Premium	View 2013 GT-R ›
2013	Nissan GT-R	Black Edition	View 2013 GT-R ›
2014	Nissan GT-R	Black Edition	View 2014 GT-R ›
2014	Nissan GT-R	Premium	View 2014 GT-R ›
2014	Nissan GT-R	Track Edition	View 2014 GT-R ›
2015	Nissan GT-R	Black Edition	View 2015 GT-R ›
2015	Nissan GT-R	Nismo	View 2015 GT-R ›
2015	Nissan GT-R	Premium	View 2015 GT-R ›
2015	Nissan GT-R	Track Edition	View 2015 GT-R ›
2016	Nissan GT-R	Black Edition	View 2016 GT-R ›
2016	Nissan GT-R	Nismo	View 2016 GT-R ›
2016	Nissan GT-R	Premium	View 2016 GT-R ›
2017	Nissan GT-R	Nismo	View 2017 GT-R ›
2017	Nissan GT-R	Premium	View 2017 GT-R ›
2018	Nissan GT-R	Nismo	View 2018 GT-R ›
2018	Nissan GT-R	Premium	View 2018 GT-R ›
2018	Nissan GT-R	Pure	View 2018 GT-R ›
2018	Nissan GT-R	Track Edition	View 2018 GT-R ›
2019	Nissan GT-R	Nismo	View 2019 GT-R ›
2019	Nissan GT-R	Premium	View 2019 GT-R ›
2019	Nissan GT-R	Pure	View 2019 GT-R ›
2019	Nissan GT-R	Track Edition	View 2019 GT-R ›
2020	Nissan GT-R	50th Anniversary Edition	View 2020 GT-R ›
2020	Nissan GT-R	Nismo	View 2020 GT-R ›
2020	Nissan GT-R	Premium	View 2020 GT-R ›
2020	Nissan GT-R	Track Edition	View 2020 GT-R ›
2021	Nissan GT-R	Nismo	View 2021 GT-R ›
2021	Nissan GT-R	T-spec	View 2021 GT-R ›
2021	Nissan GT-R	Premium	View 2021 GT-R ›
2023	Nissan GT-R	Premium	View 2023 GT-R ›
2023	Nissan GT-R	Nismo	View 2023 GT-R ›
2024	Nissan GT-R	Nismo	View 2024 GT-R ›
2024	Nissan GT-R	Premium	View 2024 GT-R ›
2024	Nissan GT-R	T-spec	View 2024 GT-R ›
2014	Porsche Panamera	Turbo S	View 2014 Panamera ›
2014	Porsche Panamera	Turbo S Executive	View 2014 Panamera ›
2015	Porsche Panamera	Turbo S Executive	View 2015 Panamera ›
2015	Porsche Panamera	Turbo S	View 2015 Panamera ›
2016	Porsche Panamera	Exclusive	View 2016 Panamera ›
2016	Porsche Panamera	Turbo S	View 2016 Panamera ›
2016	Porsche Panamera	Turbo S Executive	View 2016 Panamera ›
2022	Porsche Taycan	GTS	View 2022 Taycan ›
2022	Porsche Taycan	GTS Sport Turismo	View 2022 Taycan ›
2022	Porsche Taycan	Turbo S Cross Turismo	View 2022 Taycan ›
2023	Porsche Taycan	GTS	View 2023 Taycan ›
2023	Porsche Taycan	GTS Sport Turismo	View 2023 Taycan ›
2024	Porsche Taycan	GTS	View 2024 Taycan ›
2024	Porsche Taycan	GTS Sport Turismo	View 2024 Taycan ›
2018	Volkswagen Tiguan	SEL Premium, AWD	View 2018 Tiguan ›
2018	Volkswagen Tiguan	SEL Premium, FWD	View 2018 Tiguan ›
2019	Volkswagen Tiguan	SEL Premium R-Line	View 2019 Tiguan ›
2020	Volkswagen Tiguan	SE R-Line Black, FWD	View 2020 Tiguan ›
2020	Volkswagen Tiguan	SE R-Line Black, AWD	View 2020 Tiguan ›
2020	Volkswagen Tiguan	SEL Premium R-Line	View 2020 Tiguan ›
2021	Volkswagen Tiguan	SE R-Line Black, Eng CD DGUA, AWD	View 2021 Tiguan ›
2021	Volkswagen Tiguan	SE R-Line Black, Eng CD DGUA, FWD	View 2021 Tiguan ›
2021	Volkswagen Tiguan	SE R-Line Black, Eng CD DTEA, AWD	View 2021 Tiguan ›
2021	Volkswagen Tiguan	SE R-Line Black, Eng CD DTEA, FWD	View 2021 Tiguan ›
2021	Volkswagen Tiguan	SEL Premium R-Line, Eng CD DGUA	View 2021 Tiguan ›
2021	Volkswagen Tiguan	SEL Premium R-Line, Eng CD DTEA	View 2021 Tiguan ›
2022	Volkswagen Tiguan	SEL R-Line	View 2022 Tiguan ›
2023	Volkswagen Tiguan	SEL R-Line	View 2023 Tiguan ›