Quick Answer
- A speed rating is the letter after the load index. 104Y means load index 104 (1,985 lb, 900 kg per tire) and speed rating Y (186 mph, 300 km/h).
- Michelin describes it as the maximum speed a tire can carry its maximum load at under specified test conditions. It is not a recommended driving speed.
- Fit tires that meet or exceed the speed rating on your vehicle placard or in the owner's manual.
Type the load index and speed letter from the sidewall (for example 104Y), or a full size such as 185/55R16 87V.
Speed rating Y
186 mph
300 km/h
Load index 104
1,985 lb
900 kg per tire
Rated speed
The maximum speed the tire can carry its maximum load at under test conditions (Michelin).
A speed rating is a laboratory result, not a recommended driving speed. Use the rating in your owner's manual or on the tire placard.
Get a plain-English explanation of your results and what they mean for your vehicle.
Tire Speed Rating Chart
Symbols F to T from the Continental 2025 Truck, Bus and Trailer Product Data Guide; U, H, V, W and Y from Bridgestone and Michelin.
| Speed rating | mph | km/h |
|---|---|---|
| F | 50 | 80 |
| G | 56 | 90 |
| J | 62 | 100 |
| K | 68 | 110 |
| L | 75 | 120 |
| M | 81 | 130 |
| N | 87 | 140 |
| P | 93 | 150 |
| Q | 99 | 160 |
| R | 106 | 170 |
| S | 112 | 180 |
| T | 118 | 190 |
| U | 124 | 200 |
| H | 130 | 210 |
| V | 149 | 240 |
| W | 168 | 270 |
| Y | 186 | 300 |
Common Tire Ratings Decoded
Load index and speed symbol values from the tables above. Load is the capacity per tire.
| Rating | Load index | Load per tire | Speed symbol | Rated speed |
|---|---|---|---|---|
| 91V | 91 | 1,355 lb / 615 kg | V | 149 mph / 240 km/h |
| 94H | 94 | 1,475 lb / 670 kg | H | 130 mph / 210 km/h |
| 104Y | 104 | 1,985 lb / 900 kg | Y | 186 mph / 300 km/h |
| 93Y | 93 | 1,435 lb / 650 kg | Y | 186 mph / 300 km/h |
| 96V | 96 | 1,565 lb / 710 kg | V | 149 mph / 240 km/h |
| 100Q | 100 | 1,765 lb / 800 kg | Q | 99 mph / 160 km/h |
| 108Q | 108 | 2,205 lb / 1000 kg | Q | 99 mph / 160 km/h |
| 118R | 118 | 2,910 lb / 1320 kg | R | 106 mph / 170 km/h |
| 126Q | 126 | 3,750 lb / 1700 kg | Q | 99 mph / 160 km/h |
For the full load table see the load index calculator.
Speed to Speed Rating: km/h and mph
The lowest speed symbol whose rated speed is at least the speed shown. A comparison with the chart, not advice to drive that fast.
| km/h | mph (calculated) | Lowest covering symbol |
|---|---|---|
| 100 | 62.1 | J (100 km/h) |
| 120 | 74.6 | L (120 km/h) |
| 130 | 80.8 | M (130 km/h) |
| 140 | 87.0 | N (140 km/h) |
| 160 | 99.4 | Q (160 km/h) |
| 170 | 105.6 | R (170 km/h) |
| 180 | 111.8 | S (180 km/h) |
| 200 | 124.3 | U (200 km/h) |
| 210 | 130.5 | H (210 km/h) |
| 240 | 149.1 | V (240 km/h) |
| 250 | 155.3 | W (270 km/h) |
| 280 | 174.0 | Y (300 km/h) |
What Michelin and Bridgestone Say About Speed Ratings
| Source | Statement (paraphrased) |
|---|---|
| Michelin USA, Tire Load Rating & Speed Rating Explained | The speed rating is a letter showing the maximum speed a tire can carry its maximum load at under specified conditions, printed next to the load rating (91V: load 91, speed V). Replacement tires should meet or exceed the vehicle maker's speed rating; a higher rating may be fitted. |
| Michelin USA | A lower speed rating is not recommended unless the tires carry the 3-Peak Mountain Snowflake symbol, and then the vehicle must not be driven above the tire's maximum rated speed. |
| Bridgestone | A speed rating is not a recommended travel speed. It does not apply to tires that have been damaged, altered, under-inflated, overloaded or repaired, and real capability can be lower because of inflation, wear, vehicle condition and how long a speed is held. |
| Bridgestone | A Z in the size description represents either more than 149 mph (240 km/h) or more than 186 mph (300 km/h) depending on the tire. Contact the maker for any Z-rated tire. Choose the speed rating the vehicle maker specifies and keep all four tires the same. |
Reading 104Y
104 is the load index (1,985 lb or 900 kg per tire at the maximum pressure) and Y is the speed symbol (186 mph or 300 km/h).
mph and km/h
Speeds convert at 1 mile = 1.609344 km. Rated speeds in the chart are the published values, so the mph shown is the published mph rather than a rounded conversion.
Symbol order
Letters do not run alphabetically. H sits between U and V: S 112 mph, T 118, U 124, H 130, V 149, W 168, Y 186.
Dual load indices
Some commercial sizes print two indices, for example 102/100R. The calculator shows both from the load index table; the tire maker's literature explains which applies.
The other sidewall grades are on the UTQG explainer.
How to Read a Tire Speed Rating
- 1Find the service description on the tire sidewall, for example 104Y, just after the size.
- 2Type it into the Decode tab to get the rated speed in mph and km/h and the load per tire.
- 3To check a speed, open the Speed to Rating tab, enter the speed and unit and read the lowest symbol that covers it.
- 4Compare the result with the placard or owner's manual rating for your vehicle.