Start with the decision that changes the outcome
Safe tread depth depends on conditions, but the practical question is whether the tire still has enough tread to manage wet roads, braking, and hydroplaning risk confidently.
Legal minimums and real-world safety are not always the same conversation. Drivers usually benefit from acting before the tire reaches the absolute last acceptable point.
How to narrow the field quickly
Measure the center and shoulders, look for uneven wear, and treat wet-road performance as part of the decision instead of only focusing on the legal line.
Best next move
When the tread is approaching the end of its useful life, compare live replacement options by exact size so the next move stays simple.