Live Science Verdict
The Garmin Fenix 6X Pro Solar is an all-round fitness and health tracking powerhouse, but the solar power doesn't add much and it's seriously hefty
Incredible array of exercise tracking
Constant feature upgrades
Solar power isn't worth the cost for most
Bulky and heavy on the wrist
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The Garmin Fenix 6X Pro Solar represents the best that Garmin can put in a fitness watch, and adds in the power of juicing up through the sun's rays.
That solar panel is a new addition to Garmin's lineup, designed to help those struggling to get through a multi-day ultra-marathon eke out a few moments more battery life - but underneath the intriguing new features is a powerful watch with extensive exercise tracking.
Software: Garmin OS
Compatibility: iOS, Android
Battery life: 21 days standby
Display and size: 35mm transflective display
Water resistance:10 ATM
Heart rate: Yes
Sleep tracker: Yes
Step count: Yes
The Fenix range is often the place Garmin debuts its new software features, and the 6X Pro Solar (which has been on the market for a few months now) has received multiple upgrades to its functionality in that time. It's capable of tracking your steps, sleep, and heart rate, as well as learning how you recover from high-intensity exercise to give you a tailored plan for getting the best out of your workouts.
In terms of the workouts you can track on the Garmin Fenix 6X Pro Solar, you can expect to find pretty much anything you want on here - from running to kayaking, from parachuting to bouldering, it's all available to be tracked. This sheer variety makes it one of the best fitness trackers around.
Garmin sees the Fenix range as its 'all-action' range, meaning more protection against the elements. With that more rugged design and extensive feature set, you'll need to be ready to pay a pretty penny to own this Garmin timepiece - it launched at $1149/£849 RRP, although has since come down in price slightly.
This high-end Fenix is also an accomplished smartwatch, bringing with it enhanced smartphone connectivity as well as onboard music players that mean you can dispense with your phone if you need some disconnect time while working out.
In short, if you're looking for a do-it-all watch, Garmin promises that this is it - but while it can pretty much do everything, can it do it well?
Garmin Fenix 6X Pro Solar review: Design and display
- Large frame to keep watch safe during rugged activity
- Bright and visible display in all conditions
- Easy-to-find buttons all around the edges
Let's not beat around the bush here: if you're looking for a sleek watch, the Garmin Fenix 6X Pro Solar is not it. It's got a huge frame and added heft thanks to the metals used in construction - so while it'll feel heavy the first time you strap it on, you also instantly know you can fall down a rocky waterfall and your watch (at least) will survive.
The display is a large 35mm transflective screen, with 280x280 resolution - what that means is that each pixel can reflect the sunlight very well, so in bright conditions, all your data is incredibly legible, as well as being very battery efficient too.
What's also impressive is the backlight - it fires when keys are pressed, but when running at night it intuitively knows when you're raising your wrist to see pace or distance. The screen also includes a transparent solar layer on top of the hardened glass for additional battery power, but it doesn't seem to affect the visibility of the data at all.
There are five buttons flanking the display to help you start or stop the device without needing to look, as well as trigger laps or move through menus - these can be coded to perform other functions with a long press too, which really gives you a lot of choice under the finger, and you'll quickly learn the patterns with your fingers to make starting workouts or firing up the music player seamless.
Garmin Fenix 6X Pro Solar review: Set up and usability
- Convoluted, but useful, set up
- Menus require some learning to use effectively
- Decent enough range of customisation
Setting up the Garmin Fenix 6X Pro Solar relies on Garmin Connect, a smartphone or tablet app that's incredibly well-stocked with features. However, setup can be a little on the tricky side - once you've established the connection by selecting the watch from the list, you'll be asked a fair few questions about your daily habits and connectivity preferences.
Once in, you're treated to reams of data about your activity during the day, as well as options to set up workouts, add credit or debit cards for payment on the go or connect to Wi-Fi for music syncing.
Like being OK with the heft of the Garmin Fenix 6X Pro Solar, you'll have to want a watch that lets you do a huge amount, but are on board with needing some time investment to learn where everything is.
As mentioned above, working your way through the watch is something you'll need to learn - things like setting your favorite workouts, adding a navigation course or monitoring your daily stress levels are all a couple of clicks away from a certain menu or mode.
But if you're prepared to invest the time to study the locations of all these, you'll get a lot back from the Fenix, such are the features on board.
Garmin Fenix 6X Pro Solar review: Features
- Huge array of health tracking features
- Onboard, offline Spotify playback is a big win
- Useful smartwatch functionality through the day
The Garmin Fenix 6X Pro Solar is, as we've outlined a few times already, a watch that can do it all - whether it's tracking nearly every aspect of health daily, or keeping you entertained during a pretty heavy run session, it'll be there by your side.
Given the size of this watch, you'll need to be prepared to wear it 24/7 to get the full effect of the health tracking, but it's worth it. Each feature has a good level of detail - for instance, your sleep score gives a detailed breakdown of exactly how you slept, when you woke, how long you spent in each phase and gives you tips on how to improve.
Compare this to the Apple Watch, which basically just tells you how long you slept for, and it's a gulf in difference.
We particularly liked the body battery feature, which monitors the variance in your heart rhythms (HRV) over the course of the day and can tell you how much energy you've got left, giving you the confidence to go and work out while also telling you when it's time to settle onto the sofa and recharge.
Once you spend a few weeks with these insights, the picture of how your sleep affects your resting heart rate, whether certain workouts tax you more, and how your body generally recovers becomes clear and allows you to set your own fitness agenda.
The Garmin Fenix 6X Pro Solar also uses this HRV to tell you how well you're performing on a workout - when you've exercised for a few minutes, the watch will ping with a condition score, telling you whether you're rested and ready to go or whether you're a bit depleted in energy.
While we regularly ignored this if we had a session planned (without much issue, it has to be said), it does give huge motivation to attack a workout with gusto when you hear you're rested.
One thing we'd advise is getting a chest-based heart rate monitor - some people have reported the inbuilt heart rate monitor of the Garmin Fenix 6X Pro Solar is fine, but we found that the chest strap offered more accuracy and didn't incorrectly tell us that the heart rate was soaring on an easy run, for instance.
A new feature Garmin has recently added is tailored sessions, giving recommended workouts at the start of each day depending on your recovery - you then score your performance at the end to fine-tune the accuracy of these. We like this feature when we're feeling lazy - it's like a motivating trainer on your wrist that just tells you what to do to improve.
The Garmin Fenix 6X Pro Solar packs a huge number of satellite tracking options beyond GPS, and we found the accuracy of our runs to be excellent. You can load pre-built courses into the watch (and Garmin will help you build these, based on where others run regularly) and see the directions clearly on the large display.
There are too many workout types to list here, such is the range on offer from Garmin - whether it's cycling, swimming, running, yoga, weight lifting, parachuting, boating and more, it's supported, as well as more detailed things like trail running too so you know you're getting your run properly tracked.
The battery life compared to many smartwatches is very long on the Garmin Fenix 6X Pro Solar, coming in at 21 days on standby if you don't use the onboard music player or fire up the GPS. We found we could easily go for seven different runs over the course of a week without needing to top up the charge, meaning you can get around 8-10 hours of GPS-tracked workouts at least.
Then there's the small element of the solar power glass - this is harder to test unless you're in the desert, but we did get a few days of full sunshine to try it with.
We'd say that unless you're planning on running across the desert, it's not worth picking up the solar model of the 6X - it's more costly and, at best, it mildly slows the rate of battery loss (or stops it completely if you just leave the watch lying in the fierce sun, not doing much else).
We wouldn't say it's a novelty, but it'll be a few years before solar glass is at the efficiency and cost it needs to be a real boon and be seen on mainstream running watches.
Should you buy the Garmin Fenix 6X Pro Solar?
If you want one of the best fitness watches out there, with money (and size) no object, the Garmin Fenix 6X Pro Solar is an easy recommendation. It can track so many exercises that we felt guilty for never taking it snowboarding or hiking more often, and the health tracking features really do add insights into your day.
You can easily look at one of the cheaper watches in the Fenix 6 range if you don't need the solar glass or onboard maps, but if you fancy an investment in your health, with a great companion app delivering regular and useful insights, then this is a great choice.
If this product isn't for you
You might want your fitness smartwatch to be more smart than fitness, and that's certainly where the Apple Watch Series 6 fits. It comes with excellent notifications, a pleasant vibration to grab your attention, and is well integrated with Apple's new Fitness+ service, which offers a huge variety of workouts to keep you entertained.
It offers far less battery life - you'll need to charge this every day or two - and lacks the deep fitness capability of the Fenix, but if you're an iPhone user you'll really enjoy this one.
Offering a very similar feature set to the Garmin Fenix 6X Pro Solar, the Garmin Forerunner 945 is a sleeker model for those that like the power of a high-end fitness tracker, but don't mind a little less battery.
It has a similar level of exercises to track and can function well as a triathlon model - plus packs good features to help keep you calm through breathing exercises too.
If you're looking at the cheaper end of the scale, the Fitbit Charge 5 offers a wealth of workout choices as well as a simple, clean interface and a good range of heart rate monitoring capabilities - with more to come in future software updates.
It lacks buttons and has a more limited feature set - no music playback control, for instance - but is a neat marriage of smartwatch and fitness tracker.
Gareth has been part of the consumer technology world in a career spanning three decades. He started life as a staff writer on the fledgling TechRadar, and has grown with the site (primarily as phones, tablets and wearables editor) until becoming Global Editor in Chief in 2018. Gareth has written over 4,000 articles for TechRadar, has contributed expert insight to a number of other publications, chaired panels on zeitgeist technologies, presented at the Gadget Show Live as well as representing the brand on TV and radio for multiple channels including Sky, BBC, ITV and Al-Jazeera.