Tire speed rating

Tire Speed Rating

If you’re wondering what a speed rating is for tires, you’ve come to the right place. The speed rating is another essential part of your tire’s performance. Simply put, the speed rating tells you the fastest your tire can travel safely and securely. It’s important to know this because the faster a tire rotates, the hotter the rubber will get. So, you risk damaging your tire and losing control of your vehicle if you drive faster than your speed rating.

Get to know your tire speed rating

  • Speed ratings are given letters, and each letter represents a speed between 75-186 mph. The most common are L, M, N, P, Q, R, S, T, U, H, V, W, Y and (Y).
  • Speed rating tests are completed with tires that haven't been damaged, altered, under-inflated or overloaded.
  • Your tire needs to be in optimal shape for it to match its speed rating. Your tire's speed capacity can be affected by road surfaces, wear/tear, and weather conditions.
  • When buying new tires, choose a set that meets at least the minimum speed rating suggested by the vehicle manufacturer.
  • Sometimes your speed rating is faster than the speed limit of the road. Always follow the rules of the road.
  • Speed ratings only apply when tires have not been damaged or repaired, and depend upon the proper inflation pressure.

The DOT speed rating scale

The Department of Transportation (DOT) has created its own speed rating scale, shown below. Make sure you keep in mind that tire manufacturers test their tires and assign their own speed rating.

Here’s a complete list of the DOT tire speed ratings.

S 112 mph
118 mph
U 124 mph
H 130 mph
149 mph
Z 149 mph
168 mph
186 mph
Over 186 mph

*The "Z" rating was the highest rating for tires having a maximum speed capability greater than 149 mph. As tire technology improved, this was split into the "W" and "Y" ratings.
**When a Y rating is enclosed in parentheses, it means the tire is capable of speeds in excess of 186 mph.