How to Check and Measure Tire Tread Depth

Published on

May 2, 2025

man checks tire tread depth with quarter

Tires help support the weight of your vehicle, provide traction, and assist with steering and braking - all factors that underscore the importance of keeping them in good shape. But how do you know when they're not in good shape? In this post, we'll help you understand how to check and measure tire tread depth. Read on to learn more:

Understanding Why Tire Tread Depth Matters

Your tires are an important safety component of your vehicle, and the depth of your tire tread is perhaps the biggest factor. If your tire tread is at or below 2/32", it will impact how quickly your vehicle can stop. Tires with inadequate tread depth don't grip the road well - and it impacts more than just stopping distances. The lack of grip on the road can also make your vehicle more susceptible to hydroplaning from loss of traction, make driving more difficult in winter conditions, and even lead to steering issues.

If your tire tread depth is inadequate, contact your local GreatWater garage to learn about your tire replacement options today.

The Penny and Quarter Test: Simple At-Home Methods

Two of the most simple at-home methods for checking your tire tread depth are the penny test and the quarter test. Use a penny to test tread depth at 2/32" and a quarter to test tread depth at 4/32". Here's a look at how to perform each one:

Penny Test

Grab a penny and place it into your tire tread with Abe Lincoln's head face down. If part or all of Lincoln's head is covered, your tires are in good shape. However, if you can see his entire head, then your tires are worn to 2/32" and likely need replacement immediately.

Quarter Test

The quarter test is similar to the penny test, except it uses a quarter. Place it with George Washington's head facing down into the tread. If the tread covers the top of Washington's head, your tire tread is in good shape. However, if you can see Washington's head, your tires are likely worn to 4/32" and you should start planning for a set of new tires.

Using a Tread Depth Gauge for Accurate Measurements

You can use a tire tread depth tool to get more precise measurements. These tools can be purchased from any auto or hardware store. They're simple to use and will give you an accurate tread depth measurement. When using a tread depth gauge, be sure to take several measurements at multiple points on the tire and average out the readings to come to a determination.

When to Replace Your Tires Based on Tread Wear

According to the U.S. Department of Transportation, tires should be replaced when the tread depth reaches 2/32". Additionally, you should consider replacing your tires if they're over 6 years old, regardless of tread depth.