How much tread depth is safe? The legal minimum is 2/32 inch, but the safer point to replace is 4/32 inch, because wet grip falls off well before the legal limit. A tire at 3/32 inch is legal but not safe in rain, so plan a replacement now, and check your tread with a gauge or the quarter test.
Tread depth is measured in 32nds of an inch, and the two numbers that matter are easy to mix up: legal is not the same as safe. Servik's tread_life tool turns a tread reading into a verdict. Give it your tread depth in 32nds of an inch — the one required input — plus your install and current mileages if you want a remaining-mileage range, and your ZIP code for nearby shops. Run it from /tools or ask in /chat. It returns ok, replace_soon, or replace_now against the 4/32-inch safer point and the 2/32-inch legal minimum.
A tread-depth gauge costs under $10 and gives an exact reading — it is the only method that tracks wear rate over time. With no tools, use the penny test for 2/32 inch (Lincoln's head fully visible means at or below the legal limit) or the quarter test for 4/32 inch (tread not reaching Washington's head means at or below the safer point). Wear bars molded at 2/32 inch mark the replacement point when tread wears level with them. Check monthly, at the same time as tire pressure.
Enter the depth in 32nds — for example, 3 for 3/32 inch. If you give both the mileage when the tires were installed and the current mileage, the tool adds a remaining-mileage range derived from your own wear, labeled an estimate to inspect to confirm, never a promise. A single reading alone never becomes a mileage promise.
We ran tread_life with a tread depth of 3/32 inch and no mileages. It returned the verdict "replace_soon" — replace soon, at or below the 4/32-inch safer point, and plan replacement now, especially for rain or snow driving. The numbers behind it: 1.0 thirty-second of an inch remaining above the 2/32-inch legal minimum, and 1.0 thirty-second below the 4/32-inch safer point. No mileage range was given, because no install mileage was supplied — the verdict uses depth thresholds only.
At 3/32 inch you have 1/32 inch of tread above the legal minimum. That is legal, but it is not a safe target: wet grip falls off well before the legal minimum, and the tool's guidance is to plan replacement now, especially for rain or snow driving. The tool's estimate uses only your reading and, when given, your own install and current mileages — Servik holds no tire-specific wear-rate table, so no mileage figure here is a promise, and a shop inspection confirms the verdict.
Use /get-quotes to compare local tire shops, or ask in /chat for ranked shops near your ZIP code. Tell the shop your tire size and your tread reading. Stock is not verified — call the shop to confirm your size is in stock before you go. Servik publishes no tire price: the tire itself is priced by the shop's quote.
tread_life gives no tire price — Servik publishes no tire price, and the tire itself is priced by the shop's quote. The cost to know is the inspection: a Virginia state safety inspection costs $12–$30 where regulated, and worn tires are a common failure item — a tire at or below the 2/32-inch legal minimum fails inspection in most states. A tread-depth gauge costs under $10 and is the cheapest way to catch wear before it becomes a failed inspection or a wet-road surprise.
Call a tire shop when tread_life says replace_soon or replace_now — at or below 4/32 inch, plan replacement now, especially for rain or snow driving; at or below 2/32 inch, replace immediately, because the tire is worn out, not a safe target. Also call if tread is uneven across tires or if wear bars are flush with the tread.
The safer point to replace is 4/32 inch. The legal minimum is 2/32 inch, but wet grip falls off well before that, so do not treat the legal limit as a safe target.
In most states, yes — the legal minimum is 2/32 inch, and 3/32 is 1/32 above it. But legal is not the same as safe: the tool's verdict at 3/32 is "replace_soon" because wet grip falls off well before the legal minimum. Plan replacement now, especially for rain or snow driving.
Only if you give it two readings at known mileages — the install mileage and the current mileage. A single reading, like the 3/32 example above, gives a verdict from depth thresholds only and no mileage range. Even with both mileages, the range is an estimate from your own wear, never a promise.
Hold a penny upside down in the tread: if you can see all of Lincoln's head, the tire is at or below the 2/32-inch legal limit. For the safer 4/32 point, use a quarter: if the tread does not reach Washington's head, you are at or below 4/32. A gauge under $10 is more exact than either coin test.
Local prices and pros for this job: How much does a state safety inspection cost in Richmond? → · your city (22 metros) →
Get free quotes from local pros → · Ask the Servik assistant →
Data by Servik — verified local pros from official license records and public sources. Cost figures are typical ranges, not quotes; a pro's written estimate is the real number.