The Penny Test: How to Measure Tread Depth with Penny

Think that your tire tread may be dangerously low?

Wonder if your tires need to be replaced?

At a time like this, tread depth is one an important factor in tire function that need to be considered.

In fact, there are a number of methods that can help you know whether it’s time to replace a tire.

Penny Test, however, is known as one of the simplest, most common ways to check tread depth.

It is popular for its simple routine since it requires nothing more than a penny and a few moments of your time.

Keep reading and you will find out what I mean by the “Penny Test” and how simple it is for you to measure your own existing tire tread levels.

In this article, first, it is necessary to know about tread depth. After that, we will move to the second part, which is about Penny Test – how to measure tread depth with a penny.

What Is Tread Depth

Tread depth is a vertical measurement between the top of the tread rubber to the bottom of the tire’s deepest grooves.

What Is Tread Depth

What is the tread depth of a new tire?

Tire tread depth is measured in 32nds of an inch in the United States. With new tires, the typical tread depth is 10/32” or 11/32”, and some truck, SUV and winter tires may have deeper tread depths than other models. The tread depth can tell you about your tires condition:

  • 6/32” Your tire’s tread depth is sufficient.
  • 5/32” If wet roads are a concern, consider replacing your tires.
  • 4/32” – 3/32” Seriously consider replacing your tires as soon as possible.
  • 2/32” Your tires are legally bald and need to be replaced.

What tread depth to replace tires?

It is recommended by The U.S. Department of Transportation that tires should be replaced when they reach 2/32”.

In most states, it is against the law to use tires with a tread depth less than 2/32.

However, according to most manufacturers, your tires should be replaced when the tread depth reaches 4/32” in the winter and 2/32″ in the summer.

Your tires are considered bald and a safety hazard if your tread depth wears to those levels.

Why tread depth is important

Why tread depth is important

Since life gets busier and busier, the tread depth of your tires can be easy to overlook when you’re more focused on where you’re going. However, when it comes to tire maintenance, proper tread depth is one of the most important ways to ensure your safety and performance.

With worn tires, it becomes less able to channel water and the risk of hydroplaning increases, especially at higher speeds. Grip loss on snowy or icy roads is also a concern since worn tread make your vehicle respond slowly in adverse weather conditions (rain, snow, ice,…). In addition, low tread tires are more susceptible to punctures and can also lose air pressure, which can lead to sudden blowouts. Furthermore, since punctures can cause tire failure, you can lose control of your vehicle, which is a particular problem at high speeds.

For all of those reasons above, you need to ensure that you have the right level of tread, and that your tires are still safe for you to be driving on. Tires with worn tread need to be replaced, and one of the first maintenance tricks that many car owners learn is the penny test.

The Penny Test – How it works

After understanding about tread depth and its importance, you could start figuring out whether you have the right level of tread.

Let’s dig deep into your pockets, your couch cushions or your piggy bank, grab a penny, and head out to your garage. It’s time for the penny test.

The penny test is fairly simple, however, many individuals do not know how to properly test their tires using a penny or what the results mean.

First, if you want to measure tire tread depth effectively, you need to know how to position the coin.

Place a penny (with Lincoln’s head upside down and facing you) between the tread ribs on your tire.

A good rhyming memory aid for you to use when trying to remember how the penny test works is “Head into the tread.”

The Penny Test - How it works

A “rib” is the raised portion of tread. The raised portion spans the circumference of your tire. Tire tread has several ribs.

The top of Lincoln’s head will disappear on a tire with adequate tread. If can see his chin, nose and eyes, that’s great. But you know your tire treads are too shallow and worn if you can also see the top of Lincoln’s head. If all of his head is visible, then it’s a sign that the tread has worn down too low and you have 2/32″ or less of tire tread remaining, it’s time to start shopping for new tires.

The Penny Test - How it works - 2


When using the penny tire test, DO NOT check a single tire. Try to check all four tires, remember to check various places around each tire and pay special attention to areas that look the most worn. 

Some areas of your tire will fail the penny test, but other areas, which are deeper, can pass the test. However, you should replace the tire when any areas fail the penny test, even if parts of your tread are deeper than 2/32”,

However, many drivers do not know that the penny test may not reflect all legal requirements for tread depth.

In fact, by the time you can see all of Lincoln’s head, your treads have worn low enough that your tires are in violation of safety laws and in need of immediate replacement.

Therefore, you can try other ways to check tire tread, such as using a tread depth gauge, the quarter test, and examining the treadwear indicator bar.

And finally, you should have your tires checked out by a licensed mechanic whenever you think your tires may be close to needing replacement.

When it comes to safety, tire tread is extremely important. Sometimes, you should also consider other ways to check your tread depth since Penny Test is not always the best solution.

However, Penny Test is still a good way to maintain your tires. It is also makes examining your tread depth quick and easy.

The Penny Test - How it works - 3


Check your tread depth with Penny Test regularly so you can plan ahead and get new tires right when you need them. It’s the easiest and most common method that every driver should know. I hope after you read this article, you can know more about this method and can use it to ensure your safety, as well as the longevity of your tires.

 Good luck with doing The Penny Test!

1 thought on “The Penny Test: How to Measure Tread Depth with Penny”

  1. Thanks so much. I don’t need to follow any complicated procedures to do this after reading your article. I can check the status of my car tires with a penny.


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