Tire Tread Depth Checker
Enter your measured tread depth to instantly see whether your tires are safe for dry, wet, or winter driving, and whether they're approaching the legal replacement limit.
Check your tread depth
Measure tread depth with a gauge or use the coin test, then enter the value below.
Monitor, Replace Soon
6/32" is marginal for wet roads. Plan replacement.
How to measure tire tread depth
The most accurate method is a tread depth gauge (available at auto parts stores for under $5). Insert the probe into the main tread groove and read the depth. Measure at three points across the tire width and use the shallowest reading. Alternatively, use the coin test: insert a US quarter upside-down, if you can see the top of Washington's head, your tread is below 4/32" and replacement should be planned. If you can see Lincoln's head on a penny, you are at 2/32", the legal minimum.
Tips for success
- Thresholds at a glance: 10–11/32" new; 8–9/32" good; 6–7/32" adequate dry/marginal wet; 4–5/32" plan replacement; 3/32" replace soon; 2/32" legal minimum; under 2/32" unsafe.
- Measure at three points across the tire width and use the shallowest reading, edge wear often hides on the inside edge.
- Thresholds assume all-season tires. High-performance summer tires may be unsafe at depths that are acceptable for all-season tires.
- Uneven wear (center, edge, or cupping) warrants inspection regardless of average depth, it usually signals inflation or alignment issues.
- Rotate every 5,000–7,500 miles to even out wear and squeeze more life from each set.
How tread depth affects stopping distance
- A tire at 4/32" tread requires approximately 100 feet more stopping distance on wet pavement at 60 mph than a tire at 10/32".
- At 2/32" (legal minimum), stopping distance increases by up to 50% in wet conditions compared to new tires.
- The risk of hydroplaning increases dramatically below 4/32" at highway speeds.
- For winter/snow driving, tires with less than 6/32" tread provide significantly reduced traction on snow and ice.
FAQ
What is the legal minimum tread depth in the US?
In most US states, the legal minimum tread depth is 2/32 of an inch (1.6 mm). Some states have a higher minimum for snow tires used in winter conditions. Driving on tires below the legal minimum can result in a traffic violation and, more importantly, significantly increases your risk of accident in wet or adverse conditions.
When should I replace my tires for winter driving?
Safety organizations and tire manufacturers generally recommend replacing winter tires at 6/32" (4.8 mm) rather than waiting for the legal minimum. Below 6/32", winter tire performance on snow and ice drops noticeably. All-season tires should ideally be replaced before winter use if they are below 4/32".
What causes uneven tread wear?
Uneven wear patterns indicate mechanical issues: center wear suggests overinflation; edge wear suggests underinflation; one-sided wear suggests camber misalignment; cupping (high/low spots) suggests worn shocks or struts. These issues should be diagnosed and corrected before or alongside tire replacement, otherwise new tires will wear prematurely too.
Can I mix tires with different tread depths on the same vehicle?
Mixing tires with very different tread depths can affect handling, especially on AWD vehicles where it can damage the drivetrain. As a general rule, keep tread depth variation across all four tires to within 2/32". On AWD vehicles, some manufacturers require all four tires to be within 1/32" of each other, check your owner's manual.
How do I use the penny test vs. the quarter test?
The penny test (Lincoln head down) checks for 2/32" (the legal minimum). The quarter test (Washington head down) checks for 4/32" (the recommended replacement threshold) for wet roads. If Lincoln's head is visible, replace immediately. If Washington's head is visible but not Lincoln's, plan replacement soon, especially before winter or a long road trip in rain.