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The Penny Test for Tire Tread: How to Check If You Need New Tires

Put a penny in the tread with Lincoln’s head upside down. If you can see the top of his head, it’s time for new tires. Here’s NHTSA’s guidance.

By SHOP & SPOT EditorsLast reviewed Nov 9, 2026Research-based guide · 2 sources

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Close-up of a worn tire tread.

Photo: Pexels

This guide is for drivers checking their tires before winter, or deciding whether worn tires need replacing now.

Tread is what lets your tires grip on wet, slushy or snowy roads. A worn tire may look fine at a glance, so it’s worth a quick check with a coin.

The quick answer

NHTSA says tires are not safe and should be replaced when the tread is worn down to 2/32 of an inch.1 The penny test is a quick way to check: place a penny in the tread with Lincoln’s head upside down. If you can see the top of Lincoln’s head, it’s time to replace your tires.1

How to do the penny test

  1. Park on level ground and turn off the engine.
  2. Hold a penny with Lincoln’s head pointing down into the tread.
  3. Push it into one of the main grooves.
  4. If you can see all of Lincoln’s head, the tread is worn to about 2/32 inch or less.1
  5. Repeat in several spots on every tire: inside, center and outside grooves.

Our advice: tires often wear unevenly. One shallow spot counts, even if the rest looks fine.

Check tread monthly

NHTSA recommends checking tread monthly, along with tire pressure.1 Its winter checklist also says to check tread before the season starts.2 Many tires have built-in tread wear indicator bars across the grooves; when the tread is flush with those bars, the tire is worn out (our advice: look for them while you do the penny test).

Other reasons to replace a tire

Sign What NHTSA says
Age Some vehicle manufacturers recommend replacing tires that are six to 10 years old1
Spare used as a regular tire Don’t drive on a spare as a replacement for a worn tire, except in an emergency1
Low pressure Underinflated tires are hard to spot by eye; NHTSA recommends checking monthly with an accurate gauge1

Our advice: also replace a tire with bulges, cuts in the sidewall or exposed cords, and have a tire shop look at anything you’re unsure about.

Before winter

  • Do the penny test on all four tires.
  • Check pressure with a gauge; see our cold-weather tire pressure guide.
  • Note how old your tires are.
  • Plan replacement before the first snow, not after.

Sources & method

How we researched this

  • This is a research-based guide, not a hands-on product test.
  • Every measurement and safety figure is attributed to the source it comes from. Where we give our own advice, we say so.
  • We don’t rank or recommend specific products in this guide.

Sources

  1. Tires, National Highway Traffic Safety Administration. Accessed Nov 9, 2026.
  2. Winter Weather Driving Tips, National Highway Traffic Safety Administration. Accessed Nov 9, 2026.

Review history

  • Published Nov 9, 2026.