Tire Tread Depth Checker
Enter your tread depth to get a safety rating, estimated miles remaining, and stopping distance comparison.
Tread Depth Reference Chart
| Depth (32nds) | Depth (mm) | Rating | Action |
|---|
Wear Pattern Diagnosis
Center Wear
Worn down the middle of the tread — tire is overinflated. Reduce to door jamb specification.
Edge Wear (both sides)
Both edges worn, center intact — tire is underinflated. Inflate to correct PSI immediately.
One-Side Edge Wear
Only one shoulder worn — alignment or camber problem. Have alignment checked.
Cupping / Scalloping
Dips or cups around the tread — worn or damaged shock absorbers or struts. Have suspension inspected.
The Penny Test and Quarter Test
Insert a penny into a tread groove with Lincoln's head pointing down. If you can see all of Lincoln's head, the tread is at 2/32" or less — replace immediately. For the quarter test, use Washington's head the same way: if you see all of his head, tread is at 4/32" or less — start shopping for new tires.
Why Tread Depth Matters in Rain
Tread grooves channel water away from the contact patch. At 2/32" tread depth, wet stopping distances are about 43% longer than a new tire (NHTSA data). At highway speed, that's the difference between stopping in time and a collision. Tires worn to 2/32" can hydroplane at speeds as low as 35 mph on wet roads.
When to Rotate Tires
Rotate tires every 5,000–7,500 miles. Uneven tread wear across axles is the main sign rotations have been neglected. Front tires on FWD vehicles wear 2–3x faster than rear tires due to steering and drive forces. Regular rotation extends total tire life by up to 20,000 miles.