Why you should trust us

I've been a dog owner for most of my life, from growing up with mutts to adopting my current pup, Jerry, in January 2015. Having a 45-pound pit bull in the house has given me a lot of practical experience. Thankfully he's not an escape artist, and the one time he did get out, I found him waiting patiently in the front yard.

I've also been professionally reviewing gadgets for more than six years, including authoring Wirecutter's guide to the best Bluetooth trackers, a somewhat similar category.

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. These trackers are mainly for people who know their pet is likely to get out and get lost, rather than the average pet owner. You might also like a pet tracker if you have an outdoor pet (a cat, most likely) and you'd prefer to keep tabs on its adventures throughout the day.

Because these trackers use GPS, they are much more accurate than Bluetooth trackers, which communicate their location only if they're within Bluetooth range of your phone, or if someone else running on the same tracker ecosystem happens to wander past.

Some of these trackers also monitor your pet's activity, much like a fitness tracker a person might wear. That's a fine feature to have, and something you may find useful, but we focused solely on the tracking aspect.

How we picked

The GPS pet trackers we tested. Photo: Michael Hession

Few GPS pet trackers are available right now, and the collection of models actually worth testing is even smaller. After combing through sites like Amazon and Chewy, and looking for reviews of such devices, we found a handful worth considering. From there, we dismissed trackers that relied on T-Mobile's 2G network rather than AT&T's 3G network (they all work on older-generation GSM networks). While data speed isn't a primary concern with these devices, T-Mobile's network is simply smaller than AT&T's—when you're dealing with an issue like finding your pet, you want the largest possible network. We eliminated another tracker based on its high initial cost and low owner ratings. That left us with four models to test.

How we tested

Our faithful testing pup, Jerry. Photo: Nick Guy

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 how large each tracker was, how easy it was to attach securely to a dog's collar, and if it had any power controls to worry about. Then we went through the setup process with each model, ensuring there were no major hurdles in getting it to work.

But because the primary concern with GPS pet trackers is whether they're effective at letting you find your pets, that's where we focused our testing efforts. All the trackers we tested supported some sort of "safe zone," based on maintaining a connection to a particular Wi-Fi network or base station, or staying within a defined area. When the trackers are in this zone, they don't activate their GPS radio, saving significant battery life. We tested to see how long each tracker lasted on a charge while inside a safe zone, which revealed the best-case-scenario figure—how long the battery will last when your pet doesn't leave the house.

To see how quickly and accurately each tracker was able to update its location, we sent the trackers on a 35-mile bike ride in upstate New York, periodically checking where the trackers were during the trip. At the end of the ride, we also noted the remaining battery life, gaining an idea of how long a tracker may last on an escaped pet.

The Paby (left), Tractive (center), and Whistle (right) apps. Screenshots: Nick Guy

Finally, we wandered around Manhattan to five different locations with the trackers in tow. At each stop, we turned off Bluetooth and Wi-Fi on our test phone (to make sure the trackers weren't making a direct connection with the phone, but rather relying on their 3G and GPS radios to communicate their position). We recorded both how accurate each tracker's reported locations were and how quickly each tracker's companion smartphone app updated.

Our pick: Whistle 3 GPS Pet Tracker & Activity Monitor

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 your phone. It lasts longer on a charge than any of the other contenders we tried, its hardware design is the best by a long shot, and its smartphone software is equally well thought out.

The most important aspect of any of these trackers is the ability to find your pet's location, and to do so quickly and repeatedly, since it might be on the move. While the Whistle 3 didn't stand head and shoulders above the rest of the pack in this regard, it did tie for the best. Throughout our tests, we were able to get the tracker's location within 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. But as with pulling up Maps on your phone, the accuracy can shift due to cell phone coverage, large buildings, and other factors outside of your control. We especially 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 we left the Whistle 3 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 had 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.

In our bike-ride test, the Whistle 3 performed as well as the three other trackers in location reporting, but it again bested the competition in battery life. We removed all four from their charging stations at 8:21 a.m., and at 8:00 p.m. the Whistle 3 reported 78 percent of full charge, with the next-closest competitor (the Tractive) at 65 percent. Having a longer-lasting battery is important, because it means you have to charge the device less frequently and you have a longer window to find your pet if it gets lost. There's also the combination of the two: Unlike with a smartphone, where you can wait to charge your handset until it's almost dead, you have to recharge a tracker well before the battery is low so you have time to find your wandering pet.

The Whistle 3 also has the best physical design of any pet tracker we tested. It's the lightest we tested at just under an ounce, which for a small cat could make a real difference in comfort. At 1.4 inches wide by 1.2 inches tall, it's not too obtrusive. Whistle says the tracker is designed for pets heavier than 8 pounds, and while we don't think small animals will have issues with the weight of the tracker, its bulk may prove more frustrating for a toy dog or a cat. The collar mount has a sturdy band that holds it securely—even on small collars—though Whistle recommends a collar at least 1 inch wide. (We had something of a hard time getting the band off to put the mount on the collar, but we'd rather have it be a little difficult to put on and take off if that means it's less likely to fall off.) The Whistle 3 itself then securely snaps into the mount with a twist. It 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 take purposefully or accidentally. The Whistle 3 is also rated IP67, meaning it's dust-tight and can survive being immersed in up to a meter of water. If your dog gets out and swims through a river, the Whistle 3 will still work.

The band that holds the Whistle 3's mount to the collar is sturdy and not particularly easy to remove, which is a good thing. Photo: Michael Hession

The Whistle 3's charging base uses the same attachment system to hold the tracker in place, save for the button to release it. We like this secure mount, especially compared with competing trackers that can easily dislodge from their chargers or be ambiguous about their charging state.

Whistle's app (for iOS and Android) is among the easiest to use. At the forefront is the most important thing: your pet's location. A tray at the bottom of the screen displays the current battery life, the distance from home, and when the location last updated. When your pet is lost, the app offers an option to update the location manually right on the map, as well as a tracking mode that updates the location every 90 seconds. The app also has an activity panel that tracks how much exercise your pet has gotten, as well as a screen that lets you set up additional safe zones or alter the original zone.

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. That's more expensive than the plans for some other trackers, which means that some pricier models are actually a bit less expensive to own over, say, two years, but considering the Whistle 3's performance, we think it's worth it.

Few sites review pet trackers, but the Whistle 3 is the recipient of PCMag's Editors' Choice designation for its "strong combination of performance and price," with the publication citing long battery life and great hardware.

Flaws but not dealbreakers

Like all GPS pet trackers, the Whistle 3 is limited by its battery life and its access to a cellular network. If your pet gets out when the battery happens to be low, or in an area with poor AT&T coverage, your chances of finding Fido decrease greatly. None of these trackers, not even the Whistle 3, can claim to be a panacea for pet escapes. Consider one as an extra line of defense that may help you in a worst-case scenario.

All the trackers we tested are also pretty chunky, meaning they might not be a great fit for cats or toy dogs who may not tolerate having such a (comparatively) big device around the neck. Whistle recommends its trackers for pets 8 pounds and larger.

Despite its name, the Whistle is totally silent. Unlike with the Link AKC and Paby trackers we tested, or Bluetooth trackers, you can't use the app to trigger a sound to help you find your pet hiding in the underbrush.

Two Wirecutter writers testing the Whistle 3 found the setup process to be a hassle, with the app crashing multiple times. Eventually, each tester was able to complete the steps and was happy with the actual service provided, but some people may be turned off by this initial interaction.

In one of our test locations in Manhattan, the Whistle 3 was unable to update its location. We don't know the exact reason it didn't update, but we had no issues in subsequent trials. Other trackers had more severe or more prolonged service interruptions in our testing, as we note in the Competition section.

What about a Tile or other Bluetooth tracker?

A Bluetooth tracker may seem appealing for pet tracking. A Tile Mate, for example, costs less than half the price of even the cheapest of these GPS pet trackers, and you don't have to pay an ongoing subscription fee. Battery life is roughly a year, not days. A Tile is smaller than any of the pet trackers we tested, and the Tile app provides an experience similar to that of the Whistle app. If you're in an urban area with a decent number of other Tile owners, the tracking can be fairly accurate.

The problem is that a Tile or other Bluetooth tracker would help you find your pet only if you're very close to your pet, or if someone else who uses that brand of tracker—and thus is part of that tracker's crowd-finding system—is very close. And with the latter, there's usually a delay before you get a notification, at which point your pet may be long gone. At best, the crowd-finding feature of a Bluetooth tracker can give you an idea of the general area your pet is (or was) in.

A Bluetooth tracker may work in the right scenario. But if you're concerned about finding an escaped pet, we think the peace of mind a GPS tracker offers is worth the extra cost, as substantial as it may be.

What to look forward to

Whistle released two new GPS pet trackers: the Whistle Go and Whistle Go Explore. The Whistle Go's battery lasts for up to 10 days, while the Whistle Go Explore can run for up to 20 days. Both versions offer live tracking, as opposed to the Whistle 3's 60-second interval. We'll update this guide with our results when we've finished testing.

The competition

The Paby 3G GPS Pet Tracker & Activity Monitor was our runner-up pick, but it's since been discontinued. It was fast and accurate at telling you your pet's location, but its battery didn't last nearly as long as our top pick's. Its design also looked cheaper and felt more plasticky.

The Link AKC Smart Collar is perhaps the nicest looking of the tracker models we tested, but unfortunately that's all it has going for it. With this model's American Kennel Club branding, we expected better performance, but we ended up disappointed. The Link AKC is the most expensive tracker that requires a service plan, currently coming in at about $100 more than the competition before you factor in the $10 monthly fee (one- or two-year plans offer a cheaper rate). Part of this cost is surely due to the leather dog collar included in the kit. The collar is available in four sizes, and the company will replace the collar for free if your dog grows out of it. The tracker itself is also the largest we tested, and Link AKC representatives told us it's specifically for use with dogs weighing 15 pounds or more. Cats need not apply.

In our battery testing, the Link AKC collar was dead within two days on a home Wi-Fi network. Rather than showing the percentage charge left, the app shows battery level in one-quarter increments, which isn't very useful. During our bike-ride test, the Link AKC collar simply didn't pick up a signal, so at no point could we track where it was or compare its tracking against the others. And because of the lack of a granular battery indicator, we couldn't tell exactly how much battery remained at the end, but it was in the red, suggesting it had less than 25 percent. (Link AKC recommends charging the collar every night alongside your phone on the included base station, but given our results, we're not sure even a full charge would be enough to make it through a "lost day"—not to mention if your pet is lost for longer (or if your dog runs off in the middle of the night). PCMag had a better experience with the Link AKC collar, going so far as to say the device "comes so close to being a dream tracker in many ways." But even if the tracking had worked perfectly, the size, price, and battery life put this one out of the competition. (As we were preparing this guide for publication, the company informed us of an upcoming firmware update with "improved Bluetooth connectivity and faster, more accurate GPS tracking." But, again, the issues we noted are too problematic for us to recommend this tracker, even if the improvements are significant.)

The Tractive GPS Pet Tracker was unreliable in our tests. During our bike ride, it didn't update for several hours, and we found that it took longer to provide its location than the other trackers while travelling through Manhattan. And because it offers no option to update the position manually, you're at the whim of when the app chooses (or is able) to do so. The Tractive also has the least secure-feeling clip, a plastic bracket that feels like it could get knocked off pretty easily.

We considered testing the Nuzzle pet activity and GPS tracker. It's the only tracker that doesn't require a monthly service plan, but that cost is front-loaded into the price of the device itself, which is the most expensive of any we found. The current review scores on Amazon are also significantly lower than those of any other tracker we considered, with a majority giving the Nuzzle only one star. At this writing, the Nuzzle has gone out of stock on Amazon and the price has shot up even higher, which in our experience usually isn't a good sign; it is still available at its official retail price from Nuzzle's website.

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

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