Tread depth gauges

What to check before you buy

• Measure in several grooves, inside, middle and outside. Uneven wear points to alignment or pressure.
• No gauge at hand: the penny test. Lincoln's head down in a groove: if you see all of his head, there is 2/32 of an inch or less left.
• The small bars across the grooves are wear indicators: tread level with them is worn out.

Good to know

• Tires should be replaced when the tread is down to 2/32 of an inch.^1,2,3
• If you often drive on wet roads, consider new tires at about 4/32 of an inch.^3,4,5
• Most new car tires start with about 10/32 to 11/32 of an inch of tread.^3,6
• Quarter test: put a quarter upside down in a groove. If you can see the top of Washington's head, about 4/32 of an inch or less is left.^2,3,4
• Most US states treat 2/32 of an inch as the legal minimum tread depth.^4,6

How we checked this page

Checked on October 16, 2026. We kept a fact only when two independent sources agree, and each one is numbered to its sources below. We never write a price: the listings come straight from eBay and show what sellers ask. This page was written with an AI assistant and checked against the sources below.