New tires start around 10–11/32" of tread; Ontario's legal minimum is 1.5 mm (about 2/32"), but that is a bald tire — plan to replace around 4/32" if you drive in the rain, and around 6/32" for winter tires, which lose their deep-snow bite by then. A toonie in the groove gives you a quick read at home, and Taylor Tire measures tread and pressure free any time.
The numbers that matter
Tread depth is measured in 32nds of an inch. A new all-season tire starts around 10–11/32"; winter tires often start deeper, around 12/32". From there, three thresholds matter:
- 2/32" (1.5 mm) — Ontario's legal minimum for passenger vehicles. This is a bald tire: almost no ability to channel water, very long wet stops. Every tire also has built-in wear bars — small rubber ridges running across the grooves at exactly 2/32". Tread flush with the bars means the tire is legally worn out.
- 4/32" — the practical floor for wet driving. Braking distance in the rain degrades sharply below this, long before the tire is "illegal". If you drive year-round in GTA weather, this is the number to plan around.
- 6/32" — where winter tires lose their deep-snow bite. The tall blocks and sipes that grip snow are mostly gone by then, even though plenty of rubber remains for summer use.
Check tread monthly and before any road trip — and check all four tires, in more than one groove. Or skip the guesswork: we measure tread and pressure free, no appointment needed.
What uneven wear is telling you
How the tread wears matters as much as how much is left. Run your hand across the tire and compare the shoulders to the centre:
- Both edges worn, centre fine — chronic underinflation. The tire folds inward and rides on its shoulders.
- Centre worn, edges fine — overinflation. The tire balloons and rides on its middle.
- One side worn — alignment is off. Worth fixing before it eats the new set too; see our guide on alignment with new tires.
- Front tires wearing much faster than rear — normal on front-wheel-drive cars, and exactly what regular rotation evens out.
Catch a pattern early and the fix is cheap — air, a rotation, an alignment. Catch it late and it is a new pair of tires.
Tread is not the whole story — tires age too
Rubber hardens with age, so an old tire grips worse even with deep tread — a common surprise on low-mileage cars and long-stored winter sets. Every tire carries a DOT date code on the sidewall: the last four digits are the week and year it was made (for example 3523 = week 35 of 2023). If your tires are pushing six years or more, or the sidewall shows fine cracking, have them looked at — we read the date code as part of the free check. Not sure where to find it? Our guide to reading the sidewall walks through every marking.
The toonie test, step by step
- Grab a toonie and find the main grooves — the deep channels running around the tire.
- Insert the toonie into a groove, bear side facing you, bear's paws pointing down.
- If the tread reaches the bear's paws, the tire is roughly half worn or better — keep driving, keep checking monthly.
- If you can see all of the silver outer ring, the tread is down near the limit — time to replace. The toonie is only an approximation: a tread depth gauge, or our free check at the counter, gives you the real number.
Common questions
Is 4/32" enough tread for winter driving?
Not really. Winter tires lose most of their deep-snow traction around 6/32" — the tall blocks and sipes that bite into snow are largely gone. At 4/32" a winter tire is legal, but it is no longer doing its winter job. Plan the replacement before the season, not mid-January.
How accurate is the toonie test?
It is a quick approximation — good enough to tell "plenty left" from "getting low", not good enough to make the final call. A tread depth gauge reads to the exact 32nd, and our free tread check does the same in under a minute.
How often should I check my tread?
Once a month, and always before a road trip. Check all four tires in more than one groove, and glance at the wear pattern while you are there — uneven wear caught early is a cheap fix.
My tread is fine but the tires are old — do I still need to replace them?
Possibly. Rubber hardens over time, so grip fades even with deep tread. If the DOT date code puts the tires at six years or more, or you see fine cracks in the sidewall, bring them in — we check age and condition free along with the tread.
Questions about your own car? Bring it to the counter — straight answers, all-in prices, same-day when the schedule allows.
Updated 2026-08-11 · Taylor Tire, Markham