How to Read the DOT Date Code on Your Tyres

A tyre with plenty of tread can still be too old to trust. Rubber ages whether the tyre is driven or not, and in the Australian sun it ages fast. The good news is that every tyre carries its own birth date stamped into the sidewall — the DOT date code — and once you know how to read it, checking a tyre’s age takes about ten seconds. This is essential before buying used tyres, using an old spare, or deciding whether a tyre is due for replacement.

What is the DOT date code?

DOT stands for the U.S. Department of Transportation, and the code is a manufacturing identifier moulded into the sidewall of virtually every tyre sold in Australia. The full string identifies the plant that made the tyre, its size and the manufacturer’s own codes — but the part you care about for age is the final four digits, which record when the tyre was built.

How do you read the four-digit date code?

Since the year 2000, the date has been a four-digit number in WWYY format:

• The first two digits are the week of the year, from 01 to 53.
• The last two digits are the year.

So a code ending in 2620 means week 26 of 2020 — roughly late June 2020. A code ending in 0824 means week 8 of 2024, around late February. That is all there is to it.

One warning: tyres made before the year 2000 used a three-digit code. If you ever find a three-digit date, the tyre is at least a quarter of a century old and should not be on a road vehicle. In practice, any tyre that old is unsafe regardless.

Where is the DOT code on the tyre?

Look on the sidewall, near the rim edge, for the letters DOT followed by a series of characters ending in the four-digit date. Here is the catch that trips people up: manufacturers are only required to show the full code, including the date, on one side of the tyre — and it is often the inner sidewall facing the vehicle. If you cannot find the date on the outward-facing side, check the back of the tyre. You may need to turn the steering to full lock to see the front tyres, or shine a torch behind the wheel. Learning to read a tyre sidewall in full makes the whole marking much easier to interpret.

Why does the tyre’s age matter?

Rubber degrades over time through oxidation and UV exposure, which is exactly why the date code matters more in Australia than in cooler climates. An old tyre can look perfect and still have hardened, cracked or weakened rubber. The date code lets you judge age independently of tread depth. It matters most when you are:

• Buying tyres. Even “new” tyres have a manufacture date — check you are not being sold old stock. It is doubly important with second-hand tyres, where age is often the real problem.
• Checking a spare. Spares sit unused for years. See how old is too old for an unused spare.
• Deciding on replacement. Many manufacturers and safety bodies advise reviewing tyres from around five years old and replacing by about ten years regardless of tread.

For the full picture, read should you replace tyres over five years old, do tyres expire, and how UV damage and dry rot shorten tyre life in the Australian sun. Age is just one of the signs it is time to replace tyres, and it works alongside reading the wear pattern.

Frequently asked questions

Where exactly is the DOT date code?

On the sidewall near the rim, after the letters DOT. The full date is often only on the inner sidewall facing the car, so check the back of the tyre if you cannot see it on the outside.

My tyre only has three digits after DOT — why?

Three-digit date codes were used on tyres made before 2000. Such a tyre is over 25 years old and must not be used on the road.

Does the date code tell me when to replace the tyre?

It tells you the age, which is one factor. As a guide, many makers suggest checking tyres from about five years and replacing by around ten years, but condition, tread and cracking all matter too. Confirm with a tyre professional.

Is a tyre’s manufacture date the same as its fitting date?

No. The DOT code is when the tyre was made, not when it was fitted. A tyre can sit in a warehouse for a long time, so always check the date even on brand-new tyres.

Replacement-age figures are general manufacturer guidance and vary by brand and conditions. Have older tyres inspected by a qualified fitter. Legal minimum tread depth in Australia is 1.5 mm in all principal grooves.

Sources: Pirelli – how to read the tyre DOT code; Tyroola Australia – locating the DOT code.