Check tire pressure when the tires are cold, using a pressure gauge at a gas station or at home

The most accurate reading comes from tires that have not been driven on for at least three hours, or driven less than a mile at low speed. This is called a cold tire. Heat from driving raises pressure inside the tire, which would give you a false high reading. Early morning before you drive, or several hours after you park, is the best time to check.

You will need a tire pressure gauge. These cost between $5 and $15 and are sold at auto parts stores, gas stations, and online. Many gas stations have a free air pump with a built-in gauge at the pump itself. If you use the station's gauge, the reading is usually reliable enough for a routine check, though a handheld gauge you own will be more consistent over time.

Your vehicle's correct tire pressure is printed on a sticker inside the driver's door jamb, not on the tire itself. The number on the tire is the maximum pressure the tire can safely hold — a different thing. Write down the correct pressure before you head to check or fill your tires.

Key Takeaways

  • Check tire pressure when tires are cold — at least three hours after driving — for an accurate reading.
  • The correct pressure for your vehicle is on a sticker inside the driver's door jamb, not printed on the tire.
  • A handheld tire pressure gauge costs $5 to $15 and gives more consistent readings than a gas station pump gauge over time.
  • Remove the valve cap, press the gauge firmly onto the valve stem, and read the number that appears on the gauge display or dial.
  • Check all four tires and the spare if your vehicle has one; pressure can vary between tires.

Where to find the correct pressure for your vehicle

Open the driver's side door and look at the door jamb — the edge where the door closes. You will see a white or silver sticker with tire and loading information. This sticker lists the correct pressure in PSI (pounds per square inch) for the front tires and rear tires. Some vehicles have the same pressure front and rear; others differ by 2 to 4 PSI.

Write this number down or take a photo of the sticker before you go to check your tires. If the sticker is missing or unreadable, you can find the same information in your owner's manual, or call your vehicle's manufacturer with your vehicle identification number (VIN).

Do not use the pressure printed on the tire sidewall. That number is the maximum pressure the tire can hold, not the pressure your vehicle needs. Using the tire's maximum pressure instead of the manufacturer's recommended pressure will make your ride harsh and wear the tires unevenly.

How to use a handheld tire pressure gauge

A handheld gauge is small, portable, and works the same way whether it is digital or analog (dial). First, remove the plastic valve cap from the tire's valve stem — the small metal post sticking out of the wheel. Set the cap somewhere you will not lose it, like in your pocket or on the ground next to you.

Press the gauge firmly onto the valve stem. You should hear a brief hiss of air. Hold the gauge straight and steady for two to three seconds. On a digital gauge, a number will appear on a small screen. On an analog gauge, a needle will move along a dial or a small rod will pop out showing the pressure. Read the number and write it down.

Remove the gauge and replace the valve cap. Repeat this process for all four tires. Pressure often varies slightly between tires — front tires may read 32 PSI while rear tires read 35 PSI, for example. Write down all four readings so you know which tires need air and which are already at the correct level.

How to use a gas station air pump gauge

Most gas stations have an air pump near the fuel pumps. The pump usually has a built-in pressure gauge on the handle. Remove your valve caps and press the gauge onto the first tire's valve stem, just as you would with a handheld gauge. The gauge on the pump will show the pressure. Write down the reading and move to the next tire.

Gas station gauges are convenient and free, but they can be less accurate than a handheld gauge you own, especially if the pump is old or heavily used. If a reading seems very different from what you expect, or if you are checking pressure regularly, a handheld gauge is worth the small cost. You can keep it in your glove box and use it anytime.

What to do if pressure is too low or too high

If a tire reads lower than the manufacturer's recommended pressure, it needs air. You can add air at a gas station pump — most pumps have a hose with a trigger that lets you control how much air goes in. Attach the hose to the valve stem, squeeze the trigger in short bursts, and check the pressure every few seconds with the pump's gauge or your handheld gauge until you reach the correct PSI.

If a tire reads higher than recommended, you need to release some air. Most tire gauges have a small button or lever on the back that releases air when pressed. Hold this button against the valve stem for one or two seconds, then check the pressure again. It takes practice to release just the right amount, so check frequently.

If one tire is consistently low after you fill it, the tire may have a slow leak. A tire shop can inspect it for punctures or valve problems. Driving on an underinflated tire for long distances can damage the tire permanently and reduce fuel economy.

How often to check tire pressure

Most vehicle manufacturers recommend checking tire pressure once a month. Many people check it seasonally — in spring and fall — which catches major pressure changes caused by temperature swings. Cold weather lowers tire pressure; warm weather raises it. A tire that is correct in winter may be slightly high in summer.

Check pressure when ready if you notice your vehicle pulling to one side, a bumpy ride, or if a tire looks visibly flat. These are signs that one or more tires may be significantly underinflated. Also check after hitting a pothole or curb, since impact can damage a tire or valve stem.

Frequently Asked Questions

Can I check tire pressure right after driving?

You can, but the reading will be higher than the true cold pressure because heat from driving increases air pressure inside the tire. For the most accurate check, wait at least three hours after driving. If you must check when ready, note that the pressure will drop by 1 to 3 PSI once the tire cools.

What does PSI mean?

PSI stands for pounds per square inch. It is the unit used to measure air pressure in tires. Your vehicle's door jamb sticker will show the correct PSI for your tires — usually between 28 and 36 PSI for most cars.

Why does my tire pressure change with the seasons?

Air expands when warm and contracts when cold. A tire that reads 32 PSI in summer may read 29 or 30 PSI in winter, even if no air has leaked out. This is normal. Check pressure in both seasons and add air in winter if needed.

Is it bad to overinflate my tires?

Yes. Overinflated tires wear faster in the center, reduce traction, and make the ride harsher. They are also more prone to damage from potholes. Always inflate to the manufacturer's recommended pressure on your door jamb sticker, not the maximum pressure on the tire.

What if my gauge gives a different reading than the gas station pump?

Gauges can vary slightly, especially if one is old or worn. If readings differ by more than 2 PSI, your handheld gauge is probably more reliable. Gas station pumps are convenient but not always precise. If you check regularly, a handheld gauge is worth owning.