According to the US Department of Transportation, improperly inflated tires waste about 5 million gallons PER DAY. That’s 2 billion gallons per year; the GAO estimates a more conservative number: 1.2 billion gallons. Still, that’s a lot of gallons.

Digital pressure meters are cheap and easy to use. Here’s how to check and fill up your tires.

Properly inflated tires are something that drivers can do *now* to save the fuel *now* rather than waiting for any new alternative modes, destinations, or infrastructure.