While your vehicle’s battery is essential to its operation, it’s also easy to forget about it—or at least take it for granted—when everything is running smoothly. Of course, that changes when your battery starts to show signs of weakness, or stops working altogether. But there’s no reason to be caught off guard by a dead battery when you can test it yourself. If you’ve never tested a car battery before, it may sound like a daunting task, but as Garrett Tortelli, a senior category manager at Batteries Plus, explains below, it’s a relatively simple—yet important—process. Here’s what you need to know.

Let’s start with the obvious: Regularly testing your car battery can help you avoid a situation where your battery dies and you’re stranded at home, work or somewhere else, says Tortelli. While there are signs that a car battery is failing, such as taking a long time to start, that’s not always the case.

Since you can’t rely on your car to let you know when the battery is low, it’s important to have it tested. “While an individual can easily test certain things on the car itself, home testing only goes so far,” Tortelli tells me. “Some tests, such as simulating an engine cranking, also known as a ‘load test,’ should be overseen by a professional with the proper tools and safety precautions.”

The easiest way to test your car battery at home is with a voltmeter or multimeter. As the name suggests, a voltmeter measures the voltage of a car battery. A multimeter also measures voltage, as well as resistance, continuity, and other things. The testing process Tortelli recommends only measures the voltage of the battery, so a voltmeter will suffice. Both of these tools are affordable and available at most hardware stores and auto parts stores, or online, like this AstroAI Multimeter ($12.99) or this KAIWEETS Multimeter ($15.99).