Not sure how to read tyre ratings, codes and sizes? Confused between tyre speed rating, tyre age markings and load index of tyres? Check out the ultimate guide where we’ve compiled all the tyre markings used by tyre manufacturers. You will learn where on your tyre to find the size and date of manufacture or the information about the rim protector. You will also find out what the tyre load rating and tyre speed index are and what the M+S marking means.
Understanding tyre markings will let you choose the best tyres for your car and contribute to better driving experience. Once you know how to read tyre markings, it will be much easier for you to maintain your vehicle’s performance and safety.
Tyre markings explained (by category)
The most common tyre markings:
All tyre markings (alphabetically):
Additional information on tyre markings:
Tyre markings - video
The most common tyre markings:
Where is the tyre size marked?
The size is indicated on the side of each tyre. Look for markings such as 205/55 R16 91 V or 195/50 R15 82 T. Information on tyre size (and often on alternative tyre sizes) may be also found:
What do tyre markings mean?
195 - Tyre width expressed in millimetres.
50 - Percentage value indicating the ratio of the tyre sidewall height (the place where the size is marked) to its width. In this case, the value "50" means 50 percent of 195 mm, i.e. 97.5 mm.
R - Radial structure of the tyre.
15 - Installation diameter, which is also the diameter of the rim, measured in inches.
82 T - Load index with a value of 82 and speed index of Class T (meaning of indexes is presented below).
C - Tyres for commercial vehicles
Tyre Speed index
Tyre Speed index indicates the maximum speed at which you can drive on the tyre. You can find it on the side of the tyre, at the end of the size marking.
The most common tyre speed ratings:
Tyre load index is another important marking on the tyre. It indicates the maximum load a tyre can safely carry when driving at the maximum speed permitted. It is absolutely forbidden to use tyres with a lower load index than the one recommended for a particular car model.
For example, a tyre with a load index of 91 may be subject to a maximum load of 615 kg. If you multiply this value by the number of tyres installed in the car, you will get the result slightly higher than the permissible maximum weight of your car with a full load.
The most common tyre load indexes:
All tyre markings (alphabetically)
#
3PMSF (three-peak mountain snowflake) - Marking shown on winter tyres and all-season tyres.
B
BasePen - The tyre has electrostatic grounding (the groove that runs through the centre of the tread includes a silica blend, which avoids electrostatic charging).
BLT - Raised Black Letters.
BSW - Black Sidewall, marking letters are black.
C
COLD - Indication to measure the pressure on cold tyres.
D
DOT - Department of Transportation - tyre properties are consistent with all the safety standards of the U.S. Department of Transportation. Next to this marking, a 12-digit identification code or serial number is indicated. At the end of the DOT number, the tyre date code is shown.
Tyre date code - This is presented at the end of the DOT number. The photo shows a Matador tyre manufactured in week 42 of 2008. Information on the age of the tyre is also on the sidewall. Look for the tyre identification number, beginning with DOT. This is a sequence of 7 to 12 characters providing the information on the entire batch of tyres produced in the factory.
The last four digits of this code (usually circled) give information about the date of the tyre’s manufacture. For example, 4208, the first two digits indicate the week of manufacture, followed by two digits of the year, which means that the tyre was manufactured in week 42 of 2008.
DSST - RunFlat tyre offered by Dunlop.
E
ECE, e, E - stands for Economic Commission of Europe, which means compliance with European regulations
EMT - Extended Mobility Tyre, driving is possible even when the tyre pressure drops to zero
F
FP - Fringe Protector or RFP - Rim Fringe Protector; Dunlop uses MFS symbol.
FR - (Felgen Ripen), rim protection against mechanical damage. It is often seen in tyres with a 55 or lower profile. This depends on the manufacturer and on the type of tyre and its size. Examples of tyre size where the rim protection is installed include 205/45 R16, 195/50 R15, 205/55 R16 (there are some exceptions). It is rarely a feature of 145/65 R15 and 235/70 R16 (SUVs) size tyres. The FR marking is not placed on the side of the tyre.
I
INSIDE - Symbol used in asymmetric tyres; it indicates that the sidewall of the tyre is to be installed toward the inside of the car, facing the wheel hub. This side of the tyre should not be visible from outside the vehicle.
J
JLB - Jointless Band made of nylon.
L
LI - Load Index, indicating the maximum load capacity of the tyre.
LT - Light Truck, indication that the tyre is designed for 4x4 vehicles and light trucks (used in the US). It is placed under the size of the tyre.
M
MAX - Maximum pressure in the tyre.
M+S - Mud and Snow is used as a marking on winter, all-season and off-road tyres. It can also be found on tyres supplied from outside of Europe. This marking is only a manufacturer's declaration, it is not an official symbol confirming the properties of winter tyres.
MFS (Maximum Flange Shield) - Rim protector; some winter tyres have a rim protector. Its aim is to protect the edge of the rim from mechanical damage which may be caused by driving onto a curb or by colliding with small objects. There are different names used for this protector depending on the tyre manufacturer. Apart from MFS, the most common names include:
RFP - Rim Fringe Protector
FP - Fringe Protector
FR (Felgen Ripen) - Rim Protecting Ring
O
OWL - Outlined White Lettering.
OUTSIDE - Used on asymmetric tyres to indicate the tyre installation sides. “Outside” means that, when installed, the sidewall with this marking must be visible from the outside of the car.
P
P - Passenger; symbol placed in front of the tyre size marking. It indicates that the tyre is designed for passenger vehicles (used in the U.S.).
PAX - Zero-pressure Michelin tyre with a stable ring inside
PSP-Beta - The tyre is provided with tabs that reduce noise emission
R
R - Radial tyre
RBL - Recessed Black Lettering.
RETREAD – Retreaded tyre.
RF - Reinforced; it indicates a reinforced tyre with a higher load capacity. It has a similar meaning to the tyres with an XL symbol. Other markings of reinforced tyres include EXL, RFD, REF, REINF.
RFT - Run Flat Tyres, used by Bridgestone, Firestone and Pirelli.
RIM PROTECTOR - The tyre has solutions to protect the rim against damage.
This kind of protection prevents damage to the rim caused by impacts or abrasions, for example, against a curb
ROF - Run On Flat, marking used by Goodyear and Dunlop to indicate tyres that may continue operation after damage and loss of internal pressure.
ROTATION - Always presented with an arrow, it indicates the rolling direction, used on directional tyres.
Reinforced tyres have a special design that allows them to be used with a higher load
RSC - Run Flat System Component. It is used on tyres compatible with the Run Flat system used on BMW cars.
RWL - Raised White Lettering.
S
SST (Self Supporting Technology) - Run On Flat, tyres that may continue operation after a puncture, even when their internal pressure drops to zero.
SI - Speed Index, indicates the upper speed limit.
T
TL - Tubeless Tyre.
TT - Tube Type Tyre
TWI - Tread Wear Indicator. TWI is present at six locations on the tyre circumference (as a raised rubber strip inside tread grooves) and it indicates the limit of permitted tread wear. When the tread is worn to the level of TWI, it means that the tyre reached a legally required minimum depth of 1.6 mm. At this stage, you should consider replacing the tyre.
U
ULW - Ultra Light Weight tyre with aramid cords.
V
VR or ZR - Speed indexes included in the tyre marking. VR and ZR indicate that the tyre may be operated at full load up to the specified speed limits:
VR - up to 210 km/h,
ZR - up to 240 km/h.
For example: 225/45 ZR17 91 - means that the tyre may be operated at full load at speeds up to 240 km/h, whereas the maximum speed for the tyre is 270 km / h.
X
XL - Extra Load = RF, a reinforced tyre with higher load capacity.
Reinforced tyres have a special design that allows them to be used with a higher load
Z
ZP - Zero Pressure, a run flat tyre from Michelin.
Additional information on tyre markings
Tyre label
From 1st November 2012, each tyre produced after 30th June 2012 must be provided with a label that gives information about its basic performance. It includes 3 parameters:
- Rolling resistance, impact on fuel consumption and CO2 emissions
- Wet grip, which gives an overview of the general level of safety provided by the tyre.
- External noise level that affects the overall level of traffic noise.
The labels give you an overall view of the performance of the tyre, but they do not present many important parameters such as key performance of winter tyres. When buying tyres, do not rely only on their labels.
Tyre labels are similar to those placed on household appliances or electronics.
How to distinguish a winter tyre from a summer tyre?
Winter tyres have their sidewall marked with a M+S (Mud + Snow) and Three Peak Mountain Snowflake symbol. Sometimes the tyre has no "M+S" marking - there is only the snowflake symbol. This also means that the tyre is designed for the winter season.
It is slightly more difficult to distinguish between a winter tyre from an all-season model. Tyres of this type, available in Europe, usually have M+S marking with the snowflake symbol. The differences are visible on the tread. All-season tyres have a lower number of cuts and grooves than a typical winter tyre, but more than a summer tyre.
Some models have an asymmetric tread pattern: one half of the tread is responsible for tyre properties in the summer (summer tread with lower number of sipes) and the other half for winter performance.
The names of all-season models often include phrases suggesting good performance throughout the year, i.e. "All Season", "Quatrac", "Quadraxer", "4Seasons", "All Weather", etc. Some manufacturers also have their own individual markings for all-season tyres. Usually, it includes symbols allowing users to easily identify the tyre type.
However, be careful with tyres that have the M+S marking without the snowflake symbol. They may be products imported from the USA where most of the tyres are marked with M+S being in fact neither winter, nor all-season tyres.
In European conditions, all-season tyres have similar performance to winter tyres and they have a symbol of a mountain top with a snowflake. The M+S marking may be also present on tyres for 4x4/SUVs regardless of the season.
To sum up, the symbol of a mountain top with a snowflake means that the tyre will perform well in typical winter conditions.
UTQG markings
UTQG markings (Uniform Tyre Quality Grading) are mainly shown on tyres from the US market, but they are also found in Europe (a tyre model may be sold on both markets). Officially, they are not applicable in Europe, so manufacturers and retailers do not provide information about their meaning and values for individual models.
These markings are shown on the sidewall of the tyre as inscriptions with specified values:
TREADWEAR – Tread resistance to wear.
TRACTION – Grip of the tyre on a wet road.
TEMPERATURE – Tyre resistance to overheating
TREADWEAR
To explain treadwear better, let’s start with the concept of a reference tyre. It is a standardised model with parameters that correspond to the TREADWEAR 100 index. Tyres introduced to the market may be marked with a TREADWEAR index that is a multiple of 20 (60 - 80 - 100 - 120 - ... 200 ... 800).
How is the index assigned? A test is carried out under controlled conditions on a route with a distance of 6,400 miles (approx. 10,300 km) at Goodfellow Air Force Base in San Angelo, Texas. The tested tyre is mounted onto a special vehicle with tyres having a 100 index. Then the tyre wear is measured.
The measurement is carried out every 800 miles (1287 km) and the tyres are accordingly re-installed (on a rotational basis). Based on the measurement results, the tyres are marked with indexes: 60, 100, 200, or 400.
If the tyre gets an index of 60, its theoretical service life is equal to 60% of the service life of the reference tyre (index 100). As a result, a tyre with an index of 60 will wear almost two times faster than a tyre with an index of 100. In turn, a tyre with index 200 will wear down two times slower than the reference tyre, but two times faster than the tyres with index 400. A model with index 400 will be four times more durable than the reference product (index 100).
TRACTION
Traction in UTQG markings is expressed with letters. AA is the highest rating, followed by A and B, whereas C is the lowest value. This marking informs the driver about the ability of stopping the car on wet surfaces.
Determining the TRACTION parameter takes place on an asphalt or concrete track in strictly defined conditions. The test car accelerates to a speed of 65 km/h and then the brakes are activated. During the test the ABS system in the vehicle is turned off.
In Europe, the lowest acceptable value of TRACTION is A. If you prefer a dynamic and aggressive driving style, try to find tyres marked with AA index. Indexes B and C are only acceptable in the USA and it’s advisable not to have such tyres in Europe. It should also be noted that the TRACTION marking does not provide information about grip on dry roads, cornering or resistance to aquaplaning.
TEMPERATURE
The last of UTQG markings is TEMPERATURE - it specifies the resistance of the tyre to overheating generated while driving. When driving at high speeds, the tyre heats up intensely and that may shorten its operational life.
In order to assign the index (A, B or C, where A is the best value) a laboratory assessment is performed. It includes a series of tests. As resistance to overheating is closely related to speed, to be awarded with Index A, the tyre must withstand a 30-minute test at the speed of 115 miles/hour (185 km/h). Index B requires a 30-minute test at a speed of 100 miles/hour (160 km/h), whereas Index C requires this test at a speed of 85 miles/h (137 km/h),
TRACTION (grip) and TEMPERATURE (resistance to overheating) markings, in Europe should have the A value at least. The TREADWEAR marking (wear resistance) will help you to select tyres that have a longer service life.
If you want to base your choice on these markings, remember that the difference between a tyre with an index of 200 and 400 will be significant. UTQG markings should be considered as purely demonstrative. There is no obligation to use them in Europe, and the values are determined in the conditions of North America.
As you can see, every tyre has a number of markings that indicate different features and parameters. However, as they are unified and based on symbolics, it does not require a lot of effort to learn how to interpret them. And knowing how to read such information as the age, load index and speed rating on tyres as may turn out very helpful.