Convert a tread-depth reading between 32nds and millimetres, then see remaining-life percent versus 2/32 legal and 4/32 wet — free, private, no signup.
Measure in a major groove, not on a wear bar.
6/32"
Depth (32nds)
4.76 mm
Depth (mm)
50%
Usable remaining
Good
Status
Depth relative to a typical new tire
Tread is still in a healthy range for everyday driving.
100% browser-based
Runs locally in this tab
No upload required
Your files never leave this device
Nothing is stored
Close the tab and the input is gone
Instant results
No queue and no server wait
Enter a gauge reading in 32nds (0–20) or millimetres (0–16). You get both units plus remaining life as a percentage between a typical new ~10/32 and the common U.S. legal minimum of 2/32. That is the conversion you want when a shop speaks 32nds and your gauge is metric.
Status uses the same scale: plenty of rubber, watch it, plan replacement, or at/under 2/32. A separate wet-weather cue around 4/32 (3 mm) reminds you that legal-dry and safe-in-rain are not the same. This is not a miles-to-go predictor from compound or driving style.
The formula is linear between typical new tread and the 2/32 legal floor. A tire that left the factory with 11/32 or a winter tire with deeper siping will not match this percent exactly — treat it as a standard passenger-tire scale, then look at the actual 32nds for the legal call.
No account and no upload. The number on the gauge never leaves this tab. Close the page and it is gone. Measure several spots around the tire; one groove can lie if the wear pattern is uneven. Nothing is stored on a server.
Use a depth gauge in the main grooves, inner, center, and outer. Ignore the raised wear bars if you are recording remaining rubber.
U.S. shops often use 32nds; metric gauges use mm. The other unit fills in automatically.
Good / monitor / replace-soon / unsafe follow depth versus ~10/32 new, ~4/32 wet, and 2/32 legal. Percent is the linear scale between new and legal min.
Inner-shoulder wear can be below legal while the center looks fine. Pair uneven readings with the wear-pattern tool.
Straight answers on privacy, limits, and how the workspace behaves.
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