Check your tire pressure with a gauge — it takes one minute per tire
You need a tire pressure gauge, which costs $5 to $15 and fits in your glove box. Remove the valve cap from one tire, press the gauge onto the valve stem until it clicks or seals, and read the number. That number is your tire's current pressure in pounds per square inch (PSI). Do this for all four tires, then compare each reading to the pressure listed on a sticker inside your driver's side door jamb — not the number on the tire sidewall, which is the maximum pressure, not the target.
The whole process takes about five minutes. You do not need an air compressor to check pressure, only to add air if a tire is low. Many gas stations have free air pumps, though some now charge. Tire shops and car dealerships check pressure for free.
Check your pressure when the tires are cold — meaning the car has been parked for at least three hours or you have driven less than a mile at low speed. Driving heats the tires and raises the pressure reading by 3 to 5 PSI, which will give you a false high number. Early morning before driving is the best time.
Key Takeaways
- A tire pressure gauge is a small, inexpensive tool you can buy at any auto parts store and keep in your car permanently.
- The correct pressure for your car is printed on a sticker inside your driver's door jamb, not on the tire itself.
- Check pressure when tires are cold — after the car has sat for at least three hours — to get an accurate reading.
- If a tire reads 3 PSI or more below the target, add air at a gas station pump or tire shop before driving.
Where to find the correct pressure for your car
Open your 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 information printed on it. This sticker lists the correct pressure for your front tires and rear tires separately, because they are often different. The sticker also shows the tire size and load rating, but you only need the pressure numbers right now.
If the sticker is missing or unreadable, you can find the same information in your owner's manual or on the manufacturer's website using your vehicle's year, make, and model. Some cars also have the pressure printed inside the fuel door or on the back of the spare tire cover.
Do not use the number printed on the tire sidewall. That number is the maximum pressure the tire can safely hold, not the pressure your car needs. Using the sidewall number will overinflate your tires and cause uneven wear and a rougher ride.
Types of tire pressure gauges and how to use each one
Stick gauges are the cheapest and most common. Press the gauge onto the valve stem until you hear a click or feel it seal. A small rod will pop out from the bottom of the gauge showing the pressure in PSI. Read the number where the rod stops. These cost $3 to $8 and work reliably, though the rod can stick if you do not clean it regularly.
Digital gauges have a small screen that displays the pressure number. You press them onto the valve stem the same way, and the reading appears in one to two seconds. They are easier to read than stick gauges, especially in low light, and cost $10 to $20. Batteries last several years.
Dial gauges have a round face with a needle, like a clock. They are durable and do not need batteries, but the needle can drift out of accuracy over time. They cost $8 to $15. Press the gauge onto the valve stem and read where the needle points.
All three types work the same way: remove the valve cap, press firmly onto the stem, and read the pressure. If the gauge does not seal properly, you will hear air leaking out. Reposition and try again. Some gauges have a small lever or trigger that helps you grip and seal them — use it if your gauge has one.
What to do if a tire is low
If a tire reads 3 PSI or more below the target pressure, add air before driving. A tire that is 5 PSI low will reduce fuel economy, cause uneven wear, and make the steering feel less responsive. A tire that is 10 PSI low can overheat and fail, especially on a long drive or in hot weather.
Drive to a gas station with an air pump. Most pumps are free, though some charge 50 cents to $2 per use. Unscrew the valve cap, press the pump nozzle onto the valve stem, and hold it in place. The pump will fill the tire automatically or you will need to press a lever — check the pump's instructions. Stop every few seconds to check the pressure with your gauge so you do not overfill. Once the tire reaches the target pressure, remove the nozzle and screw the valve cap back on.
If you do not have a gauge with you at the pump, most gas station pumps have a built-in gauge on the nozzle. It is less accurate than a handheld gauge, but it will tell you whether the tire is close to the target. When you get home, check again with your own gauge to confirm.
If a tire is only 1 to 2 PSI low, you can usually wait until your next scheduled maintenance to add air. Pressure naturally drops about 1 PSI per month in normal conditions, so a small dip is not urgent. If a tire loses 5 PSI or more in a week, there may be a slow leak — have a tire shop inspect it.
How often to check tire pressure
Check your tire pressure once a month as part of routine maintenance. Many people check it when they fill up with gas, which is a good habit. You should also check before a long road trip, especially if the weather has been very hot or cold, because temperature changes affect pressure.
Cold weather lowers tire pressure. For every 10 degrees Fahrenheit the temperature drops, tire pressure falls about 1 PSI. If your tires were at the correct pressure in fall, they may be 3 to 4 PSI low by winter. Hot weather raises pressure, so a tire that was fine in spring may be 2 to 3 PSI high by summer.
Many newer cars have a tire pressure monitoring system (TPMS) that alerts you on the dashboard when a tire is significantly low — usually 25% below the target. This warning is helpful, but it does not replace regular checking. The TPMS light means a tire has already lost enough pressure to affect performance, so you should have already caught it with a monthly check.
Common mistakes when checking tire pressure
The most common mistake is checking pressure when tires are warm. If you drive to a tire shop or gas station and check when ready, the reading will be 3 to 5 PSI higher than it actually is. This leads you to think the tire is fine when it may actually be low. Always check after the car has been parked for at least three hours.
Another mistake is comparing your tire pressure to the number on the tire sidewall instead of the door jamb sticker. The sidewall number is the maximum safe pressure, not the target. Using it will overinflate your tires, which causes the center of the tread to wear faster than the edges and makes the ride harsh.
Some people forget to replace the valve cap after checking or filling. The cap keeps dirt and moisture out of the valve stem. Without it, the stem can corrode and develop a slow leak. Always screw the cap back on.
Finally, do not assume all four tires need the same pressure. Many cars have different target pressures for the front and rear — check the door jamb sticker to see if yours does. If you add the wrong pressure to a tire, it will wear unevenly and affect handling.
Frequently Asked Questions
Can I check tire pressure without a gauge?
No. You cannot tell if a tire is low just by looking at it or pressing on it with your hand. A tire can be 10 PSI low and still look normal. You need a gauge to know the actual pressure. Gauges are cheap and last for years, so buy one and keep it in your car.
What if my tire pressure is too high?
If a tire reads more than 2 PSI above the target, let some air out. Press the small pin inside the valve stem with a tool or the back of your gauge to release air. Check the pressure every few seconds so you do not let out too much. It is easier to add air than to remove it, so go slowly.
Do I need to check the spare tire?
Yes. Check your spare tire at least twice a year. A spare that is low will not hold up a car safely if you need it. The correct pressure for a spare is usually printed on the tire itself or in your owner's manual — it may be different from the pressure for regular tires.
Why does my tire pressure warning light stay on even after I add air?
The TPMS sensor in the tire may need time to update, or the tire may have a slow leak that loses pressure again after you fill it. Drive for a few minutes to let the sensor update. If the light stays on after that, have a tire shop check for a leak or a faulty sensor.
Can cold weather cause a tire to go flat?
Cold weather lowers pressure but does not cause a flat tire. A tire that is 10 PSI low in winter is still holding air — it just needs to be refilled. A flat tire means the tire has lost almost all its air, usually because of a puncture or a faulty valve stem. If a tire goes flat, do not drive on it.