Over the past six months, Garmin has substantially updated two of its marquee GPS training devices. In a previous article, I reviewed the new Forerunner 920XT—the next generation of the Forerunner 910XT. Here, I review the newly released Fēnix 3.

In effect, the Fēnix 3 is like a 920XT on steroids. Fundamentally different than the previous Fēnix models, the Fēnix 3 provides all the functionality of the 920XT plus the standard ABC (Altimeter, Barometer, Compass) watch features of the Fēnix line. This means multisport athletes now have another viable option to choose from—especially if you are a trail runner or someone otherwise looking for a device more suited to backcountry travel and mountain sports.
In terms of price, the Fēnix 3 retails for $500 vs. the 920XT’s $450 price tag. If you purchase either one with the HRM-Run heart rate chest strap, add another $50 to those prices. Despite the $50 difference between the two models, the added features of the Fēnix 3 may be well worth it depending upon how you plan to use the device.
New Generation

My first experience with the Fēnix line of devices came in 2012 when the original Fēnix was released. Although I was using the 910XT at the time for training, I was interested in finding an ABC watch that I could use for trail runs and everyday use. When I received my REI dividend that year, I decided to splurge on the original Fēnix. I struggled with the interface for several days and became increasingly frustrated with the fact that the clock—which was supposed to automatically set to the current time zone—wasn’t working. Garmin told me there was a bug that would eventually be addressed, but I wasn’t thrilled with the prospect of having to wait a few months to get the device to work as promised. So I gave up on it and returned it.
But with the recent revamping of the Fēnix 3 in the image of the Forerunner models, I was keen to give the latest generation a try. After comparing the Fēnix 3 side by side with the 920XT for a few weeks now, I can say that I am overwhelmingly enthusiastic about it. I review the Fēnix 3 below with an eye toward how it compares to the 920XT for curious multisport athletes trying to decide between the two.
ABC Watch
Let’s start with the main difference between the Fēnix 3 and 920XT. In addition to having all the features of the 920XT, the Fēnix 3 doubles as an ABC (Altimeter, Compass, Barometer) watch. This makes it useful for mountain running, backcountry travel, climbing, etc.

Altimeter. The altimeter will automatically calibrate with your GPS reading at the start of any activity, but you can change this to calibrate continuously. If you are at a point where you know the precise elevation, you can also calibrate it manually if you desire.
Barometer. The altimeter discussed above is a barometric altimeter, which means it uses a barometer to determine elevation. The 910XT and 920XT also use barometric altimeters to determine elevation readings rather than simply relying on GPS. Devices that only use GPS for elevation are much less accurate, although you can use the TrainingPeaks elevation correction function to account for that.
In any case, as an ABC watch, the Fēnix 3 provides you with a barometric reading. This can be useful for keeping an eye on incoming weather when out in the backcountry for long trail runs or climbing forays. A drop in atmospheric pressure signals a low pressure system moving in, which typically means a storm is on the way. Rising atmospheric pressure generally signals improving weather conditions.

To keep an eye on shifting weather, there’s no need to continually check the barometer. Simply turn on the “storm alert” and the watch will alert you when the barometer drops. By default, the storm alert is set to trigger when the rate exceeds 4 millibars per 3 hours; but you can adjust the setting as you like.
Compass. You can set the compass to true north, magnetic north or grid north. The compass, along with the barometer and altimeter, makes the Fēnix 3 especially useful for backcountry travel.
Navigation
Although the 920XT provides some basic navigational features, the Fēnix 3 goes beyond what the 920XT can do—as it should since it’s an ABC watch.
Both the 920XT and Fēnix 3 allow you to:
- Save locations
- Navigate back to saved locations
- Navigate back to the start of an activity
- Create courses on Garmin Connect that you can send to the device to navigate along
In addition, the Fēnix 3 allows you to enter a coordinate and navigate to it. The Fēnix 3 also provides Sight ‘N Go functionality, which allows you to pinpoint an object in the distance, lock in the direction, and navigate to it.
Temperature

Another nice advantage of the Fēnix 3 is that it measures temperature. Since the temperature sensor is in the watch, it will be impacted by body heat while you are wearing it.
For example, I placed the Fēnix 3 on a table in a room with an ambient temperature of 79 degrees Fahrenheit, and it gave a reading of 79 degrees. But then I placed it on my wrist and, after a few minutes, it gave a reading of 84 degrees.
To avoid this distortion due to your body heat, you can link the Fēnix 3 to a separate temperature sensor made by Garmin—the Tempe ($30 MSRP).
The Tempe sensor looks much like the foot pod sensor and I suppose you could even place the Tempe on your shoe like you would a foot pod. Or you could put it on a pack or jacket—somewhere away from your skin—to get a more accurate reading of the ambient temperature.
Note that the Garmin website does not list the 910XT or 920XT as compatible devices for the Tempe sensor, so the Fēnix 3 clearly has an advantage in being able to provide temperature readings—whether on its own or paired with the external sensor.
Everyday Watch
Another area where the Fēnix 3 really stands apart from the 920XT is in its stylishness as an everyday watch. Garmin also offers a sapphire version with a metal band ($600 MSRP) to enhance the fashionable look of the Fēnix 3 even more. But even the standard version looks great for daily wear compared to the 920XT.
The face of the Fēnix 3 is round like a traditional watch as opposed to the square face of the 920XT. The face can be customized for a variety of looks that include digital or analog, how the second hand displays, what (if any) colors are used for accent, etc. The 920XT can also be customized but to a lesser extent; and either model can be further customized by downloading additional watch faces from Garmin’s Connect IQ store (more on that below).
Alarm, Stopwatch, Timer
The everyday watch features of the Fēnix 3 include an easily accessible alarm, stopwatch, and countdown timer. Although the 920XT has an alarm, it lacks the basic stopwatch and countdown timer as standalone features. When it comes to the alarm on the watch, I’m a big fan of the vibration alert. This means I can wear the watch while sleeping with ear plugs and it will vibrate in the morning at my designated wakeup time. I much prefer the gentle nudge from the vibration to the sound of an alarm.
Sunrise/Sunset Times, Moon Phase
When you customize the watch face of the Fēnix 3, you can include the current sunrise/sunset times and moon phase. With the sunrise/sunset times, you can also set an alert to remind you how long until sunrise or sunset. For example, you might want to be reminded that you have an hour left before sunset when you’re out on a long trail run. Likewise, you could set the alert to sound a half hour before sunrise, acting as an alarm to wake you up when you need to get an alpine start.
Size, Profile, Weight

Although fashionable as an everyday watch, keep in mind that the Fēnix 3 is still much bigger than a normal watch. When wearing the Fēnix 3 with a long sleeve dress shirt, I am unable to button the cuffs. So that’s one area where my trusty sleek Timex Ironman watch still can’t be beat. By comparison, I can button the cuffs when wearing the 920XT but it’s still not possible to slide the sleeve over the device to check the time.
Also, when comparing the Fēnix 3 to the fit of the 920XT during activities, the thinner profile of the 920XT makes it conform better to the contours of the wrist. In other words, the 920XT has a more form fitting feel. This is aided by the lower weight of the 920XT (61 grams) vs. the Fēnix 3 (83 grams), according to my measurements, which amounts to a difference of 22 grams. These are all tradeoffs one must weigh when choosing between these two devices.
GPS / GLONASS
Central to any GPS device is the ability to record your location. Both the Fēnix 3 and 920XT provide similar GPS settings. By default, both devices use the Smart recording option, which extends the battery life. But you can also change the GPS setting to Every Second recording to provide more accuracy. The tradeoff is battery life.
If you want even more accuracy, you can turn on GLONASS in addition to GPS. GPS, of course, stands for Global Positioning System. It was developed by the US Department of Defense. The Russian Aerospace Defense Forces developed their own system termed GLONASS, or Global Navigation Satellite System. GLONASS is therefore an alternative space-based satellite navigation system to GPS. Both offer comparable coverage and precision, and using both GPS and GLONASS in tandem can add even more precision. But, again, there is a tradeoff with battery life.
Battery Life
Garmin claims a battery life of up to 24 hours for the 920XT and up to 20 hours for the Fēnix 3 in GPS training mode (presumably with Smart recording). If you simply use either device in watch mode, Garmin claims a battery life of up to four months for the 920XT and up to six weeks for the Fēnix 3. Of course, most people will use a combination of watch mode and training mode for the devices, and the frequency of recharging will depend upon how exactly you use the device.
The first week I used my Fēnix 3, it lasted nearly the whole week before depleting the battery. During that week, I kept it on all the time, using it as a watch with the daily alarm and activity tracker activated. I also used it to record about 6.5 hours of running. All but the first two hours of that running were with the Every Second GPS recording option. At the end of that week, I was out on a two hour run and the device beeped several times telling me the battery was low; but I made it home without it dying.
On another 2 hour test run, I took both the Fēnix 3 and 920XT fully charged and set to Every Second GPS recording with GLONASS. Both devices lost 18% of the battery over the course of the run on those settings. Extrapolated out, this means the battery would be drained in about 10 hours on those settings. Keep in mind these settings maximize accuracy, which requires more battery power. However, I didn’t notice an appreciable difference in accuracy in comparison to other runs I’ve done on that route without GLONASS and just Every Second GPS recording. Unless you’re on a curvy or undulating course, simply using GPS with Every Second recording may be all that is necessary.
I like the fact that both the Fēnix 3 and 920XT are designed to minimize battery drain by turning off the GPS when not training. This makes it possible to leave them on all the time and take advantage of the watch and other functions. This certainly wasn’t the case with the older 910XT, which needed to be turned off after every workout.
Training Features and Auto Climb

When it comes to using the Fēnix 3 as a training device, the features are identical to those of the 920XT. The only difference is that the interface, buttons, and menu layout are different. As with any training device, you will need to spend some time simply using the buttons and navigating the interface to gain familiarity with its unique characteristics. There are some things I prefer on the 920XT, such as the up/down scrolling buttons aligned on the right side with the start/stop and lap buttons clearly marked on the bottom. But there are some things I prefer on the Fēnix 3, such as the more intuitive menu layout and the easier to navigate interface. In the end, either interface will work for you once you gain familiarity with it. So if you are deciding between these two devices, I wouldn’t base your decision too much on the interface elements.
In my previous review of the 920XT, I discussed the Firstbeat calculations that underlie the VO2max estimator, race time predictor, training effect (TE) indicator, and recovery adviser. All these features are identical on the Fēnix 3, as is your ability to customize data screens, add activities, etc. But the Fēnix 3 does have another added bonus feature: Auto Climb.
When you turn on the Auto Climb feature, say, for a trail run, it will show you an additional data screen when you are going uphill. The Auto Climb feature is triggered by a certain ascent rate determined by you ahead of time (the default setting is 1800 feet / hour). This can be useful if you want to see, for example, your current elevation as you climb. As with all data screens, you can customize your climb screen.
Garmin Connect, Live Track, and Connect IQ

As mentioned in my previous review of the 920XT, a nice advantage of these new devices—both the Fēnix 3 and 920XT—is that you can set up Wi-Fi and Bluetooth connections.
The Wi-Fi capability means you can set your device to automatically upload data from a workout via Wi-Fi to Garmin Connect. If you use Training Peaks to log your workouts, you can then set up a sync between Garmin Connect and Training Peaks so that any workout data transferred from your device to Garmin Connect will also be transferred to Training Peaks.
The Bluetooth Smart Technology allows you to link your device to your Bluetooth Smart (a.k.a. Bluetooth 4.0) phone. Simply install the Garmin Connect Mobile app on your phone. From your phone, you can then sync your device with Garmin Connect and take advantage of the Live Track feature.

Live Track allows you to send updates from your device to a temporary webpage that you can share with people. To use Live Track, open up Garmin Connect on your phone, turn on Bluetooth, and connect your device. Then click on the Live Track tab on the Garmin Connect app. It will ask you to enter an email address of the person you want to invite to see your workout. You can add multiple emails or even post it to Facebook or Twitter. The person on the other end will receive an email with a link to a temporary page on the Garmin Connect website. Once you start your activity, that page will include a map of your current location and other data recorded by your device (e.g. time, distance, heart rate). The page will disappear once the activity is completed and your invitee closes their browser.
Keep in mind that to use Live Track you must connect your device to a phone with Bluetooth Smart technology; and your phone obviously needs a data plan since data will be sent through your phone to the Live Track webpage. All this, of course, also uses more battery power.
Like smart phones, these new smart training devices can also be customized with third-party apps. Garmin has set up an app store called Connect IQ where you can download apps, widgets, data fields, and watch faces. This means that as developers come up with more apps and such, you will be able to customize your device in myriad ways.
For example, I downloaded a weather widget for my Fēnix 3 that shows current weather information. The widget works fine and it’s nice to be able to scroll to a screen on the watch to check the weather. But it requires that the device be connected to your nearby phone via Bluetooth. In that case, why not simply look at a weather app on your phone? Especially since keeping your device connected to your phone via Bluetooth requires more battery power in both your device and phone? So some of the widgets and applications may have more of a neatness appeal than a true utility value at this point.
The Bottom Line
is that the Fēnix 3 is effectively a 920XT with the added ABC watch features in a different watch body. The main advantages of the Fēnix 3 are the ABC watch features, extra navigational capabilities, temperature sensor, and stylishness as an everyday watch. The main disadvantages are the increased weight (22 grams more than the 920XT) and slightly bulkier profile. I don’t consider the extra $50 in the cost of the Fēnix 3 a true disadvantage because the added features are worth the added cost.
Ultimately, which one of these devices you choose will come down to how you see yourself using the device and whether you need the ABC and other features of the Fēnix 3 for your pursuits. If you’re simply looking for a multisport training device and don’t need the ABC features, the 920XT would be a great choice. But if you want a device that can double as a more stylish everyday watch and/or be used for mountain running and backcountry navigation; then the Fēnix 3 could be for you.
Additional information:
- Garmin Fēnix 3 Owner’s Manual | Fēnix 3 website | purchase on Amazon
- Garmin 920XT Owner’s Manual | 920XT website | purchase on Amazon
- Comparison of the Fēnix 3, 920XT, and 910XT on the Garmin website
- Accessories: HRM-Run | Tempe
Disclosure statement: The Fēnix 3 and 920XT tested for this review were purchased independently. The author does not receive any incentive from Garmin to use its products.