How to read the code
In 225/55R17 97H, 225 is section width in millimeters, 55 is aspect ratio, R means radial construction, 17 is wheel diameter, 97 is load index, and H is speed rating.
Free mph and km/h lookup
Free Tire Speed Rating Chart
A tire speed rating chart maps the letter in a tire's service description to its standardized laboratory speed classification. Search every rating from A1 through Y and compare mph, km/h, common applications, and ZR guidance.
Example tire code
225/55R17 97H
Here, 97 is the load index and H is the speed rating. Both matter when selecting a replacement tire.
Search the rating chart
Search a symbol, speed, or typical application, then select a row for details.
Common
32 ratings shown
| Rating | mph | km/h | Typical use |
|---|---|---|---|
| 3 mph | 5 km/h | Industrial and agricultural | |
| 6 mph | 10 km/h | Industrial and agricultural | |
| 9 mph | 15 km/h | Industrial and agricultural | |
| 12 mph | 20 km/h | Industrial and agricultural | |
| 16 mph | 25 km/h | Industrial and agricultural | |
| 19 mph | 30 km/h | Industrial and agricultural | |
| 22 mph | 35 km/h | Industrial and agricultural | |
| 25 mph | 40 km/h | Industrial and agricultural | |
| 31 mph | 50 km/h | Specialty service | |
| 37 mph | 60 km/h | Specialty service | |
| 40 mph | 65 km/h | Specialty service | |
| 43 mph | 70 km/h | Specialty service | |
| 50 mph | 80 km/h | Specialty service | |
| 56 mph | 90 km/h | Specialty service | |
| 62 mph | 100 km/h | Specialty service | |
| 68 mph | 110 km/h | Light truck and specialty | |
| 75 mph | 120 km/h | Off-road and light truck | |
| 81 mph | 130 km/h | Temporary spare | |
| 87 mph | 140 km/h | Temporary spare | |
| 93 mph | 150 km/h | Light truck and specialty | |
| 99 mph | 160 km/h | Winter and light truck | |
| 106 mph | 170 km/h | Heavy-duty light truck | |
| 112 mph | 180 km/h | Family cars and vans | |
| 118 mph | 190 km/h | Family cars and vans | |
| 124 mph | 200 km/h | Sedans and coupes | |
| 130 mph | 210 km/h | Touring and sport sedans | |
| >130 mph | >210 km/h | Legacy high performance | |
| 149 mph | 240 km/h | Performance cars | |
| >149 mph | >240 km/h | High performance | |
| 168 mph | 270 km/h | High-performance cars | |
| 186 mph | 300 km/h | Ultra-high-performance cars | |
| >186 mph | >300 km/h | Ultra-high-performance cars |
Load and speed work together
A speed symbol assumes the tire is properly inflated and not overloaded. Match both the load index and speed rating to the vehicle placard and owner's manual.
Ratings are not road speeds
Laboratory ratings do not override speed limits or account for every load, repair, pressure, wear, weather, road, and vehicle condition. Follow the lowest applicable limit.
Tire speed rating FAQ
What is a tire speed rating?
A tire speed rating is a standardized laboratory classification showing the speed capability of a properly inflated, correctly loaded, undamaged tire under controlled test conditions.
Where is the speed rating on a tire?
It is usually the final letter in the service description after the load index. In 225/55R17 97H, 97 is the load index and H is the speed rating.
What is the difference between H and V tire ratings?
H is rated up to 130 mph (210 km/h), while V is rated up to 149 mph (240 km/h) under controlled test conditions. Always follow the vehicle maker's required rating.
What do ZR, W, Y, and (Y) mean?
ZR in the size designation indicates capability above 149 mph (240 km/h). The service description refines that: W is 168 mph, Y is 186 mph, and parenthesized (Y) indicates capability above 186 mph.
Can I replace a tire with a lower speed rating?
Do not choose a lower rating without guidance from the vehicle maker or a qualified tire professional. Replacement tires should meet the placard and owner's-manual requirements for speed and load.
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