What does a (Y) speed rating mean?

(Y) means the tire was tested ABOVE 300 km/h (186 mph). No ceiling is published in the marking itself; where a maximum exists, the tire manufacturer states it. This is not the same as a plain Y, which is a rating AT that speed.

Is (Y) a fast enough rating for me?

That is set by the vehicle, not by the tire. The placard in the driver's door jamb states the speed rating the vehicle was built around, and a replacement should meet or exceed it. Local law may also require it. This site reproduces the published table and approves nothing.

Where does (Y) sit in the table?

Y (300 km/h (186 mph)) is directly below it. It is the highest symbol in the published table. The table is not alphabetical: H sits between U and V because H was once the top rating and the letters above it were added later.

(Y) speed rating

A tire marked (Y) was tested above 300 km/h (above 186 mph). The brackets are the whole point of the marking.

A speed symbol is the maximum speed the tire is rated for when it is correctly inflated, undamaged, in sound condition, and carrying no more than the load its load index allows. It is a rating, not a recommendation, and it never overrides the speed limit where you are driving.

Tested above: 300 km/h
Tested above: 186 mph
Sources: 5

Worth knowing about (Y)

Open ended. The tire was tested above 300 km/h and no ceiling is published in the marking. Where a maximum exists, the tire manufacturer states it.

Brackets change the meaning

Brackets around the speed symbol, as in 285/35ZR19 (99Y), mean the tire was tested ABOVE that symbol's speed, not at it. The brackets sometimes wrap the whole service description and sometimes only the letter; the meaning is the same either way. Brackets are not a rounding mark and not decoration, and reading (Y) as Y understates the tire.

Where (Y) sits

Speed symbols either side of (Y)
Symbol	km/h	mph
Y	300	186
(Y)	above 300	above 186

See the whole table, in speed order and alphabetically.

Questions about the (Y) rating

What does a (Y) speed rating mean?: (Y) means the tire was tested ABOVE 300 km/h (186 mph). No ceiling is published in the marking itself; where a maximum exists, the tire manufacturer states it. This is not the same as a plain Y, which is a rating AT that speed.
Is (Y) a fast enough rating for me?: That is set by the vehicle, not by the tire. The placard in the driver's door jamb states the speed rating the vehicle was built around, and a replacement should meet or exceed it. Local law may also require it. This site reproduces the published table and approves nothing.
Where does (Y) sit in the table?: Y (300 km/h (186 mph)) is directly below it. It is the highest symbol in the published table. The table is not alphabetical: H sits between U and V because H was once the top rating and the letters above it were added later.

Where these figures come from

Computed on this page, not looked up. Each figure and the arithmetic behind it:

Miles per hour miles per hour = kilometres per hour x 0.621371192237, rounded to the nearest mile per hour

Published values here were read from 5 independent sources:

Speed Ratings - CJ Tire, undated reference chart (read 2026-08-27)
Speed symbols A1 to Y in km/h and mph, plus Z, (W) and (Y)
Tire Speed Rating Chart (A1 to Y) - Your Auto Vision, 2026 revision (read 2026-08-27)
Speed symbols A1 to Y in km/h and mph, plus Z, ZR and (Y)
Tire Speed Rating Chart - Santa Ana Wheel, undated reference article (read 2026-08-27)
Speed symbols L to Y in km/h and mph, plus (Y) and the ZR designation
Load Index & Weight Ratings - rimlist, undated reference article (read 2026-08-27)
Speed symbols L to Y in km/h and mph, plus (Y) and ZR
How to Read Speed Rating, Load Index and Service Descriptions - HP Wizard, reproduces Tire Rack tire tech information (read 2026-08-27)
Speed symbols L to Y in km/h and mph; ZR and bracketed symbols with worked sidewall examples

These are independent publishers, not independent measurements. Each one reproduces a table originally set by a standards body, so agreement between them shows a value was transcribed correctly, not that the underlying table is right. Where a figure is safety relevant, check it against the tire manufacturer's own data before relying on it.