Tire Speed Rating Chart

by Gabrielle DeSantis

Driving fast puts stress on your tires. At a high enough speed, any tire will blow out. Therefore, tire manufacturers rate each model of tire for a top speed. Knowing your speed rating is important for proper maintenance. Luckily, every manufacturer stamps a tire’s top speed at the end of the tire size on the sidewall. Unluckily, the speed rating is a code, a letter representing a given number of miles per hour. Use our handy speed rating chart to find out the top speed of your tires.

How To Find Your Tires’ Speed Rating

Pirelli Formula One Tire | Photo by Darren Heath/Getty Images

First, locate your tire size stamped into each tire’s sidewall. It should be three groupings of letters and numbers, separated by two slashes. Your tire speed rating will be the final letter in your tire size. For example:

  • A tire with a size of “275/55R20/113T” has a speed rating of T
  • If a tire reads “225/65R17/102H” it has a speed rating of H
  •  When a tire is stamped “205/65R15/94V,” it has a speed rating of V

Once you know your tire’s speed rating letter, you can look it up on our tire speed rating chart.

Tire Speed Rating Chart

BROOKLYN, MICHIGAN - JUNE 07: Detail of tires being put on during practice for the NASCAR Xfinity Series LTi Printing 250 at Michigan International Speedway on June 07, 2019 in Brooklyn, Michigan. (Photo by Logan Riely/Getty Images) Have a look at our tire speed rating chart.
Goodyear NASCAR Tire | Photo by Logan Riely/Getty Images
Code km/h mph Code km/h mph
A1 5 3 L 120 75
A2 10 6 M 130 81
A3 15 9 N 140 87
A4 20 12 P 150 94
A5 25 16 Q 160 100
A6 30 19 R 170 106
A7 35 22 S 180 112
A8 40 25 T 190 118
B 50 31 U 200 124
C 60 37 H 210 130
D 65 40 V 240 149
E 70 43 Z over 240 over 149
F 80 50 W 270 168
G 90 56 (W) over 270 over 168
J 100 62 Y 300 186
K 110 68 (Y) over 300 over 186

The History of Tire Speed Rating Codes

A tire from French manufacturer Michelin is on a Bugatti Chiron during the 2018 North American International Auto Show in Detroit, Michigan, on January 16, 2018. Car makers appealed to Americans' deep love of SUVs and trucks on at the Detroit Auto Show, unveiling a host of choices from luxurious to utilitarian, while also beefing up the humble sedan. / AFP PHOTO / JIM WATSON        (Photo credit should read JIM WATSON/AFP via Getty Images) See our tire speed rating chart.
Michelin Performance Tires on a Bugatti Chiron | JIM WATSON/AFP via Getty Images

Tire speed ratings have changed a lot over the years. Once, all early tires were bias-ply tires: the steel bands that gave these tires structure overlapped at a 45-degree angle for maximum strength. But bias-ply construction limits a tire’s top speed. Then, engineers developed more reliable materials and radial-ply tires became more popular. In radial-ply tires, the structural steel bands run perpendicular to the direction of travel, as if extending from the wheel’s radius. As a result, these tires have a much higher top speed. 

Until 1991, a tire’s speed rating included its bias-ply (b) or radial (r) designation. Thus, the speed ratings appeared before the tire’s construction type, just after their aspect ratio. For example:

  • “225/65R17/102H” would have been “225/65HR17/102” 
  • “205/65R15/94V” would have been “205/65VR15/94”

Before 1991, a speed rating chart would have read as follows: SR (112 mph), HR (130 mph) and VR (in excess of 130 mph). And manufacturers gave any tire with a speed rating over 186 mph the “Y” designation.

In the future, tire technology will continue to improve, and new speed rating designations will be added to the speed rating chart. When Bugatti attempted the production car speed record, the French manufacturer contacted Michellin for cutting-edge, 300 mph tires. As a result, Michelin built carbon fiber belted high-speed tires, and Bugatti set a world speed record.

Changing Your Tire Speed Rating

Always check our tire speed rating chart. A Formula One car's right front Pirelli P Zero tyre covered in rubber debris, known as pick-up, in post race Parc Fermé at the 2011 European Grand Prix, Valencia Street Circuit, Valencia, Spain, on the 26th June 2011. (Photo by Darren Heath/Getty Images)
Tire damage | Photo by Darren Heath/Getty Images

When a manufacturer designs a tire with a speed rating of 130 mph, that tire will suffer less sidewall flex at 65 mph than a tire rated for 112 mph. As a result, the performance tire with the higher speed rating will generate less heat and may even last longer. It is not a good idea to select a lesser tire, from further up the speed rating chart. In some countries, it is illegal to downgrade your tire speed rating from the tires your car had new.

But a tire with a higher speed rating may make for a stiffer ride. Of course, you can always safely upgrade your tire to a performance tire with a higher speed rating, but do your research to see how the new tires will affect your ride quality.

RELATED: Tire Load Index Chart Explained

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