Tire Speed Rating Chart: What H, V, W, Y and Z Mean

Where to find the speed rating

Look at the size on your sidewall: 225/45R17 94V. The size ends at the 17. Then comes the service description: the number 94 is the load index, and the letter V is the speed rating.

The same letter is on your door placard, next to the size the vehicle maker specifies. That placard rating is the one that matters when you buy tires. Our guide to reading tire size walks through the rest of the line.

What a speed rating actually means

Michelin's definition: the speed rating indicates the maximum speed at which a tire can carry its maximum load under specified conditions. Continental explains how it's found: in a lab, on drum test benches, where the tire is run at progressively higher speeds under simulated loads.

Three points follow from that:

• It's a test result, not a driving recommendation. Nobody should read V as "drive at 149".
• It's really about heat. Michelin says ratings reflect the tire's overall structural integrity and heat resistance, not just its top speed capability. Pirelli describes it as the tire's ability to withstand or dissipate heat at high speeds.
• It assumes a healthy tire. Pirelli is explicit: the rating comes from a test on undamaged tires, and if a tire is old, worn down, underinflated or overloaded, the speed rating is no longer relevant.

Tire speed rating chart

These are the common passenger and light truck ratings, as published by BFGoodrich and Michelin, with Pirelli's L as the low end of the scale.

The letters in between (M through R, and U) exist too; the load and speed rating check below covers the full scale.

Why does H sit between U and V instead of in alphabetical order? BFGoodrich's explanation: H was introduced separately, was commonly thought to stand for high performance, and kept its place when the rest of the scale was standardized.

To compare two tires' ratings, or see what a letter means in mph, use the lookup below:

It also lives on its own page, so you can bookmark it.

Z, ZR and (Y)

Older and high performance tires can show ZR inside the size, as in 245/40ZR18. According to BFGoodrich, Z was once the highest rating, at 149 mph and up, until W and Y were added above it.

Today the specific rating is in the service description. A tire marked 245/40ZR18 97Y is rated Y, 186 mph. When the rating is in parentheses, as in (Y), Continental says it means 186 mph / 300 km/h or more.

Replacing tires: meet or exceed

Michelin's rule is short: replacement tires should always meet or exceed the speed rating specified by the vehicle manufacturer. Going up is allowed. Going down is not recommended.

Michelin makes one exception: lower-rated winter-capable tires marked with the three-peak mountain snowflake symbol. In South Florida that exception rarely applies.

If someone suggests a lower rating anyway, BFGoodrich spells out what it means: the car's capability drops to that of the lower-rated tire. Its example is a T-rated tire on a car specified for V, which limits the car to 118 mph instead of 149 mph.

And remember the load index sits right beside it. Our load index guide covers that number.

Mixing speed ratings

The best answer is not to. Pirelli says it is always best to avoid mixing tires with different characteristics, including speed rating, and Continental says mixing is not recommended.

If it can't be avoided for a while, for example after replacing one damaged tire:

• Lower-rated tires go on the front axle. BFGoodrich says this applies regardless of which axle is driven, to prevent a potential oversteer condition. Pirelli puts it the other way around: higher-rated tires on the rear axle.
• The lowest rating governs. The car's capability is limited to the lowest-rated tire fitted.

Does a higher speed rating mean a better tire?

It means a different tire. BFGoodrich notes that typically the higher the speed rating, the better the grip and stopping power, but the shorter the tread life, because higher ratings tend to use softer compounds and stiffer construction. That's the same trade-off our guide to touring vs performance tires covers.

Heat, pressure and the Florida angle

Continental adds a caution that matters here: under-inflation, excessive load, and high ambient temperatures may reduce the tire's actual speed capacity. A South Florida summer, a loaded SUV and a tire a few psi low stack up against that rating.

The fix is the boring one. Check pressure monthly with a gauge, cold, and set it to the door placard, as NHTSA advises. Our guide to Florida heat and tires explains how heat affects pressure and aging.

Shopping by speed rating

1. Read the size, load index and speed rating from your door placard.
2. Filter tires that meet or exceed both numbers. You can shop by size and compare candidates side by side.
3. Keep all four tires on the same rating where you can.

Tires ship free to the 48 contiguous states and DC. Extreme Tires installs at its Sunrise shop or by mobile van in Miami-Dade, Broward and Palm Beach, and see installation for how that works.

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