How To Measure Tire Tread Depth

To the question – how to measure tread depth? – there is a simple answer. You can measure the tread depth of your tires with a euro coin. Alternatively, you can use a mechanical or digital tread depth gauge. The tire wear indicator also provides information about the wear of the tires.

Why Measure Tread Depth?

The question is not only: How to measure tread depth? But also: Why? Whether winter tires, summer tires, motorcycles, or cars – measuring tread depth is child’s play. All the better, because the tire tread is the be-all and end-all when it comes to safety. If the tread is worn down, there is a corresponding lack of grip. This can be fatal, especially in winter or on a wet road. Keyword: aquaplaning. But even on dry and paved roads, the braking distance is longer if the grooves are missing.

The Optimal Tread Depth Of Winter Tires And Summer Tires – How To Measure Tread Depth?

The legislator precisely prescribes the minimum tread depth of car tires. If you want to know exactly: According to § 36 Paragraph 2 of the StVZO, only tires with a tread depth of at least 1.6 mm are allowed on the road. Failure to comply can result in hefty fines or, in the worst case, loss of control of the vehicle. It is therefore doubly worthwhile to check your tread depth regularly. It is even better to have a tread depth of at least 3 mm for summer tires and even 4 mm for winter tires. For comparison: a new tire has a tread depth of 8-9 mm.

Measure Tread Depth In Winter

How To Measure Tread Depth? – The Right Place

How to measure tread depth: It is best to measure the tread depth in the center of the tread, because this is where the tire mainly rests on the road. However, the four wheels do not always wear evenly. That’s why it’s advisable to measure at different points. Did you know? In the event of a police check, it is always the most worn spot that counts. If the tread falls below 1.6 mm in even a single spot, replace the tire immediately!

Small Excursion: Replace Unevenly Worn Tires Individually?

Tires never wear evenly. If lowering springs or a sports suspension are involved, for example, uneven wear is almost predictable. But even without tuning, the problem can hardly be avoided. An axle change is a good prevention, but once the tread is gone, even the best prophylaxis won’t help.

But can I replace individual tires or do I have to replace all four right away? For cost reasons, the former would of course be more practical. If you are unlucky, however, this will lead to the vehicle breaking free and thus to an increased risk of an accident. Specialists, therefore, recommend: Replace tires only axle by axle! In other words, the two tires on the front axles must have an almost identical tread. However, this does not necessarily have to match that on the rear axle. It is also important to always fit the wheels with a deeper profile on the rear axle.

How To Measure Tread Depth? – The Tools

This is where the tools come into play. But don’t worry. You have various options for finding out the tread depth of your tires. For a better overview, we distinguish between manual and automatic measuring devices below. How to measure tread depth? Here’s how!

Manual Gauges

How To Measure Tread Depth? – Euro Coin

The 1-euro coin: Probably the easiest and fastest way to find out the tread depth. The golden edge of the coin measures exactly 3 mm. Simply hold the coin in a tread groove and you can see whether the tread is still sufficient. Alternatively, a 2-euro coin with a 4-mm edge will do for winter tires.

tread depth with euro coin

How To Measure Tread Depth? – Mechanical Tread Depth Gauge

If you don’t trust the tip with the coin and prefer a professional approach, you can use a tread depth gauge from a specialist dealer. The use is self-explanatory. Hold the measuring stick in the tire tread and then read off the value. Et Voilà! Alternatively, of course, you can use a good old ruler or folding rule.

Digital Tread Depth Gauge – How To Measure Tread Depth?

But this can be done even more precisely: with a digital measuring device. In principle, this works in the same way as its mechanical counterpart. The difference lies in the display. The devices usually have an LCD that conveniently shows you the tread depth digitally.

How To Measure Tread Depth? – Automatic Measuring Devices

Laser Triangulation

Real professionals in traffic monitoring or workshops use laser triangulation to measure tread depth. The vehicle rolls over a measuring device installed on the floor, which then automatically determines the tread depth to the millimeter. The device also detects faulty camber and track settings.

Find Out Tread Depth Without Tools? – How To Measure Tread Depth?

But you can easily find out whether your tires are still running at minimum tread depth without any technical equipment. Have you ever heard of tread-wear indicators – TWI for short? Tread-wear indicators are small ridges distributed in the main tread grooves in the center of the tread. If the bars are on the same level as the tread, you know: A new tire is needed!

tire wear indicator image

What To Do To Make My Tires Live Longer?

How to measure tread depth? The question is now answered. Finally. But what if the rubber is wearing down at record speed? Unfortunately, wear is unavoidable because your car’s tires are under constant stress. Even while your Audi A4 or VW Golf is sitting unused in the garage, the weight of the body is acting on the tires. Nevertheless, there are a few tips to extend the life of the material:

  • Observe optimum tire pressure
  • Regularly check tire geometry
  • Continuously inspect wheels for damage
  • Store unused summer and winter tires according to instructions

Make Tire Last Longer

And of course, measure the tread depth at regular intervals! But even if you heed all the advice, wear is, as I said, quite natural. This means that even with sufficient tread depth, drivers should retire tires after at least eight years. This is not only our advice but also that of the ADAC.

Old tires are retired? You can get new summer tires, winter tires, or complete wheels in our store. Including alloy rims, of course. To find out if the alloy rims fit your car, just have a look at our 3D rim configurator! You can order the matching lock during the ordering process.

Jonathan Tim
Jonathan Tim
A bicycle geek since early childhood spent his twenties as a mechanic in bike shops. His passions include flatland BMX, unicycles, cycle touring, mountain biking, and road riding.