These are some of the main points from this video from Firestone on tire pressure:

1.  Up to 2 billion gallons of gas can be saved nation-wide if we all drove with properly inflated tires.

2.  Check your tire pressure in the morning when they are cold.

3.  Properly inflated tires tend to last longer!

4.  Around one-fourth of motorists drive with under-inflated tires.

5.  You can check the correct pressure of your tires on the driver side door jam, owner's manual, or fuel-filler door.

6.  Check your tires about once month because they lose about a pound of air each month.

Again, as you can see from these facts, keeping an electric air pump handy can save you trips to the gas station air pump that cost 75 cents and can help you get in the habit of checking your tires on a more regular basis.

Fortunately, a 12v air compressor does not have to cost you a fortune as many come with a built-in car jump starter and portable ac power for under $100.

Also, remember that a tire air compressor will come with its own pressure gauge so you can measure the amount accurately while you pump.