This Southwest App Tells You If Your Bag Fits in the Overhead Bin

Southwest just launched a cool new bag-sizing feature within its app, and TPG decided to test it out. Unlike its KLM counterpart, the bag sizer is available for any interested traveler, even without a booked flight.

The feature is accessible from the app's main menu button at the top left of the app screen. "Bag Sizer" is located toward the bottom of the menu underneath all the urgent information for booked reservations.

Once you fire up the feature, it offers a tutorial for first-time users. After your first try, the feature goes directly into camera mode to save you some time.

There's a very straightforward tutorial, similar to the ones offered by KLM and Kayak. You first scan the floor, then the bag so the app can assess the approximate size.

As with any good app, Southwest politely asks for camera access before launching the virtual sizer.

As with the last two virtual bag sizers TPG tested, we opted to test an AWAY carry-on suitcase, which is known to fit carry-on guidelines on virtually any carrier. If you happened to miss the tutorial the first time around, the app still offers helpful guidance at the bottom of the screen to walk you through the very simple process.

There's a playful disclaimer reminding travelers that Southwest employees are the final arbiters of carryon bag size - not the virtual app.

This was the most effective virtual screener I've tested yet – this one had no issue picking up on the suitcase's accurate size, and with relative speed, too.

Just a few seconds in, the bag was scanned and the Magical Sorting Hat Southwest app had made its sizing determination.

All in all, this was my favorite virtual bag-measuring feature yet. The system is quick, easy to use, and very intuitive and the functionality makes a lot of sense. Furthermore, I don't fly KLM often or utilize Kayak enough to justify keeping either app on my phone just for the sizing tool, whereas I use Southwest at least once a month on average. I'll definitely keep this function in my back pocket – literally – for my next trip.