SidewallRef

Printable sheets · Sidewall marking sheet

Sidewall marking sheet

One sheet naming every marking on a sidewall: the size and its parts, the service type prefixes, the DOT code segments, the winter symbols and the load range letter.

About 1 page printed. Every figure on this sheet is free to read on the sidewall marking reference, with its sources.

What the sheet looks like

Real rows from the sheet, rendered for everyone, so the layout can be judged before buying.

Sample rows: service type prefixes
PrefixMeans
PP-metric (passenger)
noneEuro-metric (no prefix)
LTLT-metric (light truck)
STST (special trailer)
TT (temporary spare)
CC (commercial or van)

Sidewall marking sheet

Four digits, since 2000: the first two are the week of the year (01 to 53) and the last two are the year. 2519 is the 25th week of 2019. 0824 is the 8th week of 2024.

Service type prefixes
PrefixMeansIn one line
PP-metric (passenger)A passenger car tire rated against the North American Tire and Rim Association tables.
noneEuro-metric (no prefix)No letter at all. The tire is rated against the European tyre and rim organisation tables.
LTLT-metric (light truck)Built for light truck duty, and rated for it without any derating.
STST (special trailer)For trailer axles only. Not for a vehicle that steers or drives.
TT (temporary spare)The space saver spare. Restricted speed and restricted distance.
CC (commercial or van)A commercial van tire. The C sits after the rim diameter, not before the width.
DOT identification number
SegmentLengthSays
DOT3 lettersThe tire is certified to United States federal motor vehicle safety standards. Without it the tire is not legal for road use in the US.
Plant code2 or 3 charactersThe factory that built the tire. Two characters historically; a third was permitted from April 2015, so both lengths are in circulation.
Size code2 charactersThe manufacturer's own code for the size. It is not standardised - each manufacturer assigns these itself, so the same two characters mean different sizes at different brands.
Type codeup to 4 characters, optionalOptional manufacturer code for the tire line, used for internal tracking. Carries no consumer meaning and is absent on some tires.
Date code4 digits (3 before 2000)Week and year of manufacture. This is the part that tells you the tire's age, and the only part of the code most people ever need.

M+S, M&S or M/S means mud and snow, and it is awarded on TREAD GEOMETRY alone. No tire is driven on snow to earn it and no performance is measured. Most all season tires carry it. It is a description of a tread pattern, not a winter capability.

The three peak mountain snowflake is earned by testing. The tire has to deliver at least 110 percent of a reference tire's traction on medium packed snow, which is a 10 percent margin over the baseline, before it may carry the symbol. That is a real threshold, and it is why the symbol and M+S are not interchangeable.

This is geometry, not fitment approval. It says what a size measures, never whether it fits a vehicle.

SidewallRef · sidewall reference · figures cross-checked against the sources listed on /markings/

What stays free

Every size page, the size decoder, the comparison tool, the load index table, the speed symbol table and every marking reference stay free forever, with no account and no limit.

Where these figures come from

Published values here were read from 17 independent sources:

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.