Who this is for

A GPS pet tracker, like most emergency gear, is something you hope you never have to use. The device uses an embedded GPS transponder as well as cellular data signals to communicate your pet's location at a given time. The idea is that if your pet escapes, you'll receive a notification via an app, have the ability to track its location in real time, and be safely reunited.

How we picked and tested

The GPS pet trackers we tested. Photo: Michael Hession

A good pet tracker should be easy to set up and must stay on your pet, so we started by evaluating the hardware itself. We looked at each tracker's size and how securely it attaches to a collar. We also examined any power controls present on the collars and tested battery life in both the "safe zone" and in the real world. In the safe zone, the collar's GPS radio is deactivated, significantly saving battery life. The safe zone is determined by maintaining a connection to a particular Wi-Fi network or base station, or by staying within a defined area.

To track accuracy, we sent the trackers on a 35-mile bike ride in upstate New York, periodically checking the trackers' status and reported location. We also visited five locations in Manhattan to test both how accurate each tracker's reported locations were and how quickly each tracker's companion smartphone app updated. To read more about our test procedures, please see our full guide.

Our pick

Photo: Nick Guy

If you're concerned about your pet getting away and you want a tool to help you more easily find it, the best option is the Whistle 3 GPS Pet Tracker & Activity Monitor. This tracker is as accurate as any model we tested, quickly transmitting its GPS signal back to our phone. It lasts longer on a charge than any of the other contenders we tried, its hardware design is the best by far, and its smartphone software is equally well-thought-out.

Throughout our tests, we were able to get the Whistle 3's location in a matter of seconds, and that reported location was always close enough to the actual location that we'd be able to find our pet easily. We like that the Whistle 3's smartphone app shows you not only where the tracker is but also where you are in relation to it, which is handy if you're trying to find your pet in an unfamiliar area. The app also has a button to refresh the location manually, something other trackers' apps lack.

Where the Whistle 3 most sets itself apart from other models is in battery life. When left undisturbed inside a home Wi-Fi safe zone, it didn't just last longer than any other tracker—it even surpassed the amount of time we allotted for the test. Thirteen days into the test, and six days after the next-longest battery gave out, the Whistle 3's battery was still at 69 percent.

The Whistle 3 won't come off unless you hold down a spring-loaded button and twist a quarter turn, an action your opposable-thumb-lacking companion is unlikely to purposefully or accidentally take. The Whistle 3 is also rated IP67, meaning it's dust-tight and can survive being immersed in up to a meter of water.

Like most competing trackers, the Whistle 3 requires a 3G service plan. You can choose to pay $10 a month with no commitment, or save by paying for a year ($100) or even two ($170) in advance.

Runner-up

Photo: Nick Guy

We think you should go with the Whistle 3, but if for some reason you can't, the Paby 3G GPS Pet Tracker & Activity Monitor is the next-best alternative. It updated faster and was more accurate in our tests than other trackers, and we greatly appreciate that its companion smartphone app indicates when it last updated the tracker's location, so you know if you have current information. The hardware also feels more secure on a pet's collar than other models do. But compared with the Whistle, the battery doesn't last as long, and the charger isn't nearly as good.

Vaguely shaped like a bow tie, the Paby tracker is small enough that it fits on most dog or cat collars, attaching with a strong band. You have to use a tiny screwdriver to replace the band if it ever breaks, but the tool is included in the box. And by "box," we mean the collapsible water bowl the tracker comes packaged in—a very cool and wholly practical design choice.

The Paby's charger is its biggest failure. The magnetic pad has an extremely weak magnet, and it rests right up against the aforementioned rubber band, so the charger can too easily pop off, resulting in an uncharged tracker. That's especially a problem with this tracker because it has pretty poor battery life: It lasted only four days in our safe-zone test, and was down to 53 percent at the end of our bike-ride test.

This guide may have been updated by Wirecutter. To see the current recommendation, please go here.

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