Does your iPhone 6s randomly shut off before the battery is fully drained? Apple last week launched a repair program for this issue, and now it's easy to check if you're eligible for a free battery.

As MacRumors notes, Cupertino's new tool lets you enter your phone's serial number and find out if the company is willing to give you a new battery for free, before making a trip to the store. You can get your phone's serial number by tapping on Settings > General > About.

As Apple notes on the page, the problem affects "a very small number of iPhone 6s devices." While this is a battery issue, rest assured that Apple says it's "not a safety issue," so don't worry about any Galaxy Note 7-like explosions.

If you are eligible for a new battery, you can take your phone to an Apple retail store or one of the company's authorized service providers to get it fixed. Wireless carriers aren't participating in the program, so don't waste your time taking your phone there.

Before heading in for a fix, Apple recommends backing up your data to iTunes or iCloud, turning off the "Find my iPhone" feature, and erasing data and settings in Settings > General > Reset > Erase all Content and Settings.

Note that if your phone has another issue that interferes with a battery replacement—if the screen is cracked, for example—Apple won't replace the battery unless you agree to have that fault repaired as well, which won't be free.