An H-rated tire is a tire generally found on sports sedans and coupes; it is rated for a maximum speed of 130 mph. The H speed rating sits between the T and V rating, which is unusual because the rest of the ratings are in American alphabetical order.
When the speed rating system was still in its beginning stages, the "H" stood for "high-performance," which is why it does not follow alphabetical order as of 2015. The tire speed rating system states how fast a tire is capable of traveling, although the recommended traveling speed is usually much lower. Speed tests are performed in controlled environments that rarely represent real driving conditions. The most common tire ratings are T, H, V, W and Z.
T-rated tires are most commonly used on minivans and sedans; they have a maximum speed rating of 118 mph. V-rated tires have a maximum top speed of 149 mph and are commonly found on sports cars. W-rated tires have a maximum speed of 168 and are also used on sports cars. Z-rated tires are always used on high-performance sports cars; the Z rating represents a maximum speed of more than 149 mph or 186 mph, depending on the tire.