Checking your tire pressure is arguably the best thing you can do for your vehicle. But there are so many different pressure gauges, how do they all work?

We’ve all heard about how we should regularly check the air in our tires, especially before going on a long trip, right? The fact is, your car will run better and you will get more life out of your tires if they’re at the right pressure. But with all the different gauge options out there it can be difficult to know how they work. In this article, we’ll go over the different types of gauges out there and how to read them before providing a step-by-step guide on how to check the air pressure in your tires.

Reading a tire pressure gauge will depend on the type of gauge it is, but they’re all easy to use. Depending on what kind you’re using, you will read the tire pressure based on the position of the measuring stick, the needle position, or just reading the digital readout.

I’ve worked in an automotive shop for the better part of the decade and work on cars as a hobby in addition to that. Through the years, I’ve used just about every tire pressure gauge imaginable and know how they work. Through my hands-on experience as well as research on the topic, I’ve compiled the guide below to teach you everything you need to know about tire pressure gauges and how to check your own pressure.

How To Read a Tire Pressure Gauge



What is a Tire Pressure Gauge and How Does it Work?

Checking the tire pressure in your car is one of the easiest ways to make sure your vehicle can run as efficiently as possible. Keeping your tires at the right pressure helps them last longer while also providing the ideal combination of a comfortable ride while still being as fuel-efficient as possible. But if you’ve never checked the tire pressure in your tires yourself, you might be wondering how it works.

Enter the tire pressure gauge.

A simple device in principle, a tire pressure gauge is designed to do exactly what it sounds like — measure the air pressure in your tires. Super easy to use and small enough to fit in your glove box, purse, or even your pocket, they are a great tool to have for anyone with a car. For all tire pressure gauges, they are designed to simply attach to the valve stem of the tire/wheel combination and report a pressure reading of how much air is inside, measured in pounds per square inch (psi).

Vehicles will have unique air pressure guidelines from the manufacturer that you can find posted on a placard along the door jam of the driver’s door or placed on the inside of the driver’s door itself. The numbers that you see on the placard, typically between 32-35 psi for most vehicles, are what you want to compare the readings to that you get from your tire pressure gauge. If your tires are lower than what the placard says, then you want to add air; if they’re higher, remove air.

But how do tire pressure gauges work and how do you read them? There are a few different styles on the market that you can use. So let’s take a quick look at each one to get a better idea of how they’re used, and then we’ll go over a step-by-step guide to checking your tire pressure.

Stick Tire Pressure Gauge

Likely the most common thing that people picture when they think of a tire gauge is the stick gauge or pencil gauge. This is the narrow silver-colored tube that has a measuring stick on the inside with psi readings that you’ve likely seen in movies and TV shows. They’re very quick and easy to use. With a stick or pencil gauge, just push the gauge down on the valve stem and the measuring stick inside will move out from the device. On the stick, you’ll see psi readings, and the line where the stick stops is the corresponding pressure inside the tire.

Analog Tire Pressure Gauge

Another fairly common tire pressure gauge is the classic analog gauge. An analog gauge is another mechanical device that shows a physical reading of the tire pressure, just like the stick gauge. But with an analog gauge, the readout will be on a circular pressure gauge with a needle pointing to the pressure. Just wait for the needle to stabilize and see where it’s pointed, that value will correspond to the pressure of the tire.

Digital Tire Pressure Gauge

In this day and age of technology, it only makes sense that there is a digital version of the tire pressure gauge to make it even easier to read than ever before. Digital gauges come in a few different shapes and sizes but they’re all super simple to use. Most will require you to press a button to turn it on before putting it on the tire so that it can calibrate with the outside air. Once ready, just push the digital gauge onto the valve stem as before and it will spit out a number right on its display that you can read. It doesn’t get any easier!

How to Check The Air in Your Tires Using a Pressure Gauge

Now that you have an idea of what a tire pressure gauge is and how they work in general, let’s go over the basic steps involved in checking your tire pressure. It’s a simple process that is super important for the life of your tires and to make sure your vehicle is as safe as possible to drive. And once you learn how to check the pressure once, it’s like riding a bike; you won’t soon forget!

So without further adieu, here’s a step-by-step guide on how to check your tire pressure:

  1. Remove Valve Stem Cap: The valve stem is the rubber or metal stem protruding through the wheel that allows you to add or remove air from the tire. They will have a cap on them to prevent corrosion from the elements. Carefully remove this cap to access the valve stem. It should twist off, but if it’s corroded on there, don’t use pliers as they will likely break the valve stem.
  2. Use the Gauge on the Valve Stem: If you look inside the valve stem, you might notice a little plunger. When that’s pressed, air is able to flow in or out of the stem. With your tire pressure gauge in hand, gently but firmly press it down onto the valve stem. It will usually make a very brief sound like air is coming out before it seals almost immediately, this is normal.
  3. Wait for the Pressure Reading: The reading that you’re looking for will depend on the type of gauge that you’re using, as mentioned up above. For an electronic gauge, you may need to press a button for the gauge to take the reading and display it. On an analog gauge, you will have to wait for the needle or dial to stabilize. And with a stick gauge, you will just have to see how far it pushes the stick out.
  4. Adjust Tire Pressure as Needed: Once you have the tire pressure reading, you can compare it to what the pressure is supposed to be set at. You can find this information on a little placard inside the driver’s door, as mentioned above. Always go by this placard, not the pressure you see on the tire. The pressure printed on the tire is the maximum pressure for that tire, not what it should actually be set at.
  5. Put the Valve Stem Cap Back on: Once you’re finished checking the pressure (and adjusting it if you choose to), carefully put the valve stem cap back on. Before you do, take a quick look inside the cap to see if the o-ring is still seated at the top. If not, you’ll want to grab a new cap to keep the stem protected from the elements. But don’t worry, they’re very cheap.

That’s all there is to it. Once you understand the process and do it a few times, it is super simple to do your entire vehicle in just a couple of minutes at the most. For how easy it is, it’s one of the best time investments you can make when it comes to keeping your vehicle properly maintained and in tip-top shape!


Charles Redding

Charles Redding

I've spent many years selling cars, working with auto detailers, mechanics, dealership service teams, quoting and researching car insurance, modding my own cars, and much more.

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