Garmin Fenix 8 review: a brilliantly built and fantastically featured GPS watch for adventurers who want it all (at a cost)

Garmin Fenix 8: first impressions 

The Fenix 8 was one of the most eagerly anticipated drops in Garmin watch history when it finally landed last summer, and that says a lot about the success of its predecessor. The Fenix 7 is already a top-tier GPS watch with tremendous battery life and great training tools for trail runners, and the Fenix 8 has taken that winning formula and added more navigation tools, the option of a crystal clear AMOLED display, voice commands and more smartwatch functions like the ability to take and make phone calls.

There are tons of options to pick from with this rugged watch that's purposely built to withstand the grime and bashing of your outdoor adventures. Choose between a 43mm, 47mm or 51mm case size and a bright AMOLED display or solar option which doesn't have as bright a display. There's also the Fenix E which has the AMOLED display but a stainless steel case and is missing a few of the features, such as the flashlight and dive buttons.

In design, this watch looks a lot like the 7, with five buttons to operate it: a Start/Stop and Back button on one side and Up, Down and Options on the other. It's a high profile watch, and by that we mean pretty bulky – enough that you'll find it annoying to wear with long sleeves.

As for features, there are so many it's hard to know what to talk about, so let's start with what's new. Both the heart rate sensor and GPS tracking have been updated for improved accuracy, and Dynamic Routing means backcountry runners and hikers can now access really nifty functions like being guided back to your starting point.

If you're following a preloaded route, the topographical maps are brilliantly clear, even on the smallest case, though we did find we sometimes had to open the Garmin Connect app to get it to refresh. Once you're out on the trail, the GPS is super sharp and responsive if you get off route.

If aquatic adventures are more your thing, the case is 40-meter dive-rated and has leakproof metal buttons and support for scuba and apnea dive activities, all tested to U.S. military standards for thermal, shock and water resistance.

Almost no matter what you're doing and how cold your hands are, it's easy to operate between the responsive touchscreen and voice commands and the interface is really intuitive for a watch that has so many options.

The battery life is said to be improved, with the official specs claiming up to 21 days in smartwatch mode (28 days with solar) and 67 hours in GPS only. Crucially though, it offers up to 48 hours if you're using it in All Satellite Mode which means greater accuracy but a faster drain on your battery, and it does have an energy saving mode. In our field tests, we had to charge it every five or six days when using it to track a run, hike, swim or yoga for typically at least 90 minutes a day.

There's a whole suite of data and performance tools you can pull from this watch, such as Training Readiness Score, Race Predictor, Running Lactate Threshold, Body Battery, Abnormal Heart Rate Alerts and of course, VO2 Max. It's impossible that you could ever use them all unless it's your full-time job, but also unlikely that you'll ever think of something it doesn't have.

The flashlight is the same as on the Fenix 7, operated by the double click of the Options button, and it's still one of the best features. It's bright enough for night running, plus the red light mode is just brilliant for not blinding your run club friends and getting dressed in the dark without annoying your partner.

All in, this is one of Garmin's best watches yet and a fun toy for those who love the outdoors with some excellent training tools, but there's no denying that many people will be priced out of this one. You're unlikely to not have a lot of fun with it, but it remains to be seen whether there's a a big enough market for those who want a truly rugged watch like this with so many smartwatch functions.

Garmin Fenix 8: in the field 

I've been testing the Garmin Fenix 8 for the past three weeks and during that time I've used it for six trail runs (two in remote mountainous terrain), one road run, three hikes, two pool swims and nine yoga classes. I've been wearing it on my right wrist and my Coros Pace 3 on my left wrist to see how the two compare in terms of metrics.

Here’s how it performed:

Design

I tested the 43mm case, which is the smallest size, but it is still surprisingly high profile. It's a big, bulky watch and takes up my entire wrist. I'm on the small side, sure, but not tiny so if you have more of a birdlike physique, I don't think you can wear this watch (try the Fenix 7S instead).

For the first couple of days I found I had a slight bruise on my wrist bone from wearing it. I got used to that, but I do find that this watch is a little awkward to wear and I wouldn't be able to sleep with it on, so I'm missing out on some of the training tools.

I've been testing it during winter, so when I'm trail running and hiking I typically have multiple layers on, all with long sleeves. The size of this watch means that clothes are both difficult to get on and off when wearing it, and also that it's exceptionally difficult to pull up my sleeve to check the map. For that reason, I've mostly resorted to pulling all my sleeves up over it and hiking or running with a cold right hand. I'm sure it's great for people who run in T-shirts in summer.

The flip side of that is that it's a really robust build. Not only can it withstand being dropped and bashed around, I don't find myself accidentally pressing buttons and pausing it when wrestling with my sleeves.

Features

This watch is brimming with features, having taken all the best ones from the rugged Fenix line and added more smartwatch features, so I'll just focus on the new ones and the ones I used the most. The GPS has been updated and had some new functions added, so as a mountain runner and hiker I was most excited to explore these.

I started off with the Back to Start function, which I think is genius for people like me who quite like to just hare off into the hills without a plan. To be on the safe side, I used it in a huge, meandering country park where I never seem to be able to create the same running route twice, but was sure I wouldn't end up too lost. Instead of trying to figure out my route or memorize my return, I just ran until I reached about 4k, then hit Back to Start and followed my watch the way I came. It's so easy.

The other big new update is the dive function, but since I'm not a diver I haven't been able to test this. That said, I did make sure to get into the pool for a couple of 1,000m swims and I noticed that the homescreen cycles through different data, so it wasn't always easy to see how far I'd swum without stopping. Ordinarily, I like to just swim without counting and check my watch every so often to see how far I've done. There may be a way to edit this, but it seems obvious to me that it should be a default. I noticed that when I finished, it prompted me to make sure I drained the speaker of water, which I thought was smart.

The voice command works great and means that I can just double press the Options button and say "start trail running" rather than having to scroll through the menu. I also found I really liked the touchscreen, something I had disabled on my Coros.

I'm not so interested in the smartwatch functions so I can't say I spent a lot of time taking phone calls on my watch, though I tested it out for journalistic purposes, and I also don't listen to music when I run so I didn't go through the process of adding Spotify and pairing my headphones, but this is something you can do.

As for training tools, there's practically an infinite suite now, many which you'll find on the 7. Because of the watch's large size, I wasn't able to sleep with it on for three nights, which is required to get a Training Readiness score and HRV (although in my interview with Michael Crawley, he explains that 24-hour use isn't actually required for accurate readings so I hope they rethink this). Anyway, I really like accessing the other metrics like VO2 Max, Hill Score and Running Lactate Threshold and I noticed these got updated as I logged more workouts.

Finally, even though it's available on the 7 and the Enduro, I need to mention the flashlight because it's just such a great feature. I was having issues with my headlamp on a night run and the flashlight function on this watch absolutely saved me. It's really bright (and adjustable) and is surprisingly good at lighting up the path even though it's on my wrist rather than a focused beam. It also means I always have a secondary light source for backup when I'm fiddling with my headlamp.

Best of all, when we stopped to enjoy the stars I could quickly turn it down to red light to avoid dazzling my friends. I also use the red light function regularly now when I get dressed in the dark for my 6:30am yoga class so I don't disturb my boyfriend and I'm going to be very sad to go back to a regular watch that doesn't have this.

Performance

This was my first time using a Garmin – I've been wearing the Coros Pace 3 for over a year, and I was a bit worried that it would be overly complicated to use when I saw it had five buttons compared to two on my Coros. However, as soon as I fired it up I got a handy graphic from Garmin showing me what each button does what and I was away. The touchscreen function helps, but I found the whole interface to be instantly intuitive, even if there are myriad options, which was a relief.

To test the updated GPS, I first used a preloaded map during an 11k night run in the Campsies, which are hills not too far from Glasgow where I live. These hills are well-traveled by hikers, but they're not known for great paths, so I was keen to see how my watch would handle them. Even though I'm familiar with the area, I downloaded the map from AllTrails to follow, a process which I found fairly painless, although it did require me doing it via my laptop and I'd prefer to be able to do it all on my phone.

Once I got going I could tell almost instantly that the GPS was spot-on, giving me an alert if I veered off route, which I did once or twice to avoid boggy areas. Next, I made sure to test this on a route I'd never hiked before, and it was a tricky enough route I don't think I'd have managed it without my watch, which kept me right the whole way.

Just out of interest, I also tried doing a Zone 2 trail run to see how well it worked. It was pretty straightforward, alerting me every time my heart rate got too high and then again when I was back in Zone 2. That part worked brilliantly, with the only real issue being that it's impossible to run in Zone 2, but that's another article.

The problem with this was that for my next run, which was a four-hour mountain run with a group, I just went back to Trail Running and hit start, not realizing that it had saved my previous options. The result was my watch beeped at me annoyingly every 30 seconds, even when I was eating lunch (surely if I was stationary it would know I wasn't trying to be in Zone 2?). I was the least popular person on the trail that day and although I accept it must have been user error, I think it would be better for it to default back to regular settings than assume you want to run in Zone 2 until you die, since I still haven't figured out how to turn it off.

One other slight quirk I noticed is that the map doesn't always update, so sometimes when I'm at home it thinks I'm still 40 miles away until I open the Garmin Connect app on my phone. That's not ordinarily a problem, but it could be if you were out in the wild and you lost your phone.

Garmin says the heart rate sensor has been updated too, which is the main reason I wore this watch in tandem with my Coros Pace 3 for every activity. After interviewing Crawley about GPS watches, and learning that his experiments sometimes showed different watches to be as much as 40bpm apart, I was expecting I might see a big difference between the two watches. However, in every activity the two watches were only about three beats per minute off, which I think is a good sign they're both pretty accurate.

Finally, battery life. This is a complicated thing to estimate because how long you get out of any watch all depends on which version you buy and how you use it. Basically, I used mine for an activity or two every day, usually for a minimum of 90 minutes, often with GPS, sometimes without (as in yoga) and sometimes with the battery-draining flashlight I love so much. What I discovered is that with this level of use, I had to charge every five or six days. That's a lot more frequently than my Coros, but miles better than an Apple Watch. If you wear yours for a more moderate 30 - 60 minutes five days a week, I reckon you'll get more like twice that, and if you're training for an ultra or doing a long distance hike, you'd better bring a portable charger.

Speaking of chargers, this one requires Garmin's proprietary plug charger, not a standard USB, which I don't own, but luckily I could charge it on my laptop.

Value

There's no denying that this is a phenomenally expensive watch. At $999 for the 43mm and $1,199 for the 51mm, it's even more than the Fenix 7, which we thought was expensive when it came out, and more in line with the Enduro 3. Will you get one of the best-performing smartwatches on the market for that price? Undoubtedly. But do you really need so much functionality? That's really up to you. I can't help but think the overlap between people who really love smartwatch functionality and rugged outdoors features might be small, but then again, there's a big market of people who just like great gadgets.

There is one workaround that's worth knowing about, and that's the Garmin Fenix E, which comes in 47mm only for $799. It has an AMOLED display but a stainless steel case, a shorter battery life, no flashlight and lacks the Dive-proof buttons.

Garmin Fenix 8: the bottom line 

After years of saying I'm not a Garmin person, it turns out I could be a Garmin person if there's a flashlight and excellent navigation thrown in. If you love adventuring in the backcountry, fancy gadgets with tons of tech and have a wad of cash burning a hole in your pocket, this watch is definitely for you, and clearly one of the best from Garmin yet, but it is big and bulky which can be a pain at times.

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