Tire speed rating or the speed index/symbol specify the top speed at which the tire can carry a load corresponding to its load index, under service conditions specified by the manufacturer.

The speed rating is identified as a part of the tire size designation or the tire’s service description, together with the load index.

The speed rating system as it is used today was developed in Europe as a response to the need for classifying tires into standardized speeds. It describes the top speed for which a tire is certified.

Speed rating on tires is expressed by a letter from A to Z (the speed symbol), ranging from 5 km/h (3 mph) to above 300 km/h (186 mph). For e.g. the letter "T" defines the maximum speed limit at 190 kph/118mph (Please see the tire speed rating chart below).

"Z" Ratings

A tire rated with the letter "Z" in the tire size designation (i.e. P275/40ZR17 93W or 275/40ZR17 93Y) is the tire which have a maximum speed capability above 240 kph/149mph. Tires having a maximum speed capability above 300 km/h (186 mph) must have "Z" in the size designation and the service description must include Y in parenthesis (i.e. P275/40ZR17 (93Y)).

Tire speed ratings

Speed SymbolSpeed (kmh)Speed (mph)
E 70 43
F 80 50
G 90 56
J 100 62
K 110 68
L 120 75
M 130 81
N 140 87
P 150 94
Q 160 100
R 170 106
S 180 112
T 190 118
U 200 124
H 210 130
V 240 149
W ZR* 270 168
Y ZR* 300 186
(Y) ZR** Above 300 Above 186 (consult manufacturer)

* Tire manufacturer may or may not (is not obligated to) include a "Z" in the size designation.
** Tire manufacturer must include a "Z" in the size designation.

See the Load index chart.

Check out other charts: Tire size chart, Tire conversion chart.

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