Best GPS Watches for Ultrarunning & Trail Running in 2021

Ultrarunners have very specific requirements when it comes to choosing which GPS running watch to buy. Because of these requirements, and the fact that the 4 leading brands for this niche are Garmin, Suunto, Coros, and Polar, my list of the best GPS watches for ultrarunning is small. Whoever needed too much choice anyway? Listed below are the features that ultrarunning watches should ideally have, to make them worthy of being a long term investment:

1. a very long battery life to be able to track vast distances over many hours, sometimes even days. There’s nothing worse than having your watch die on you in the middle of an ultra race.
2. actionable features that help us know when to adjust our effort levels, like a heart rate monitor, for example. Being able to know exactly how much climbing/elevation gain you have accumulated, with an estimate of how much still remains is invaluable data to an ultra runner.
3. navigation features in case you get lost in the mountains and need to find your way back on course or back to safety. Also very important if you want to explore new trail routes, without having to carry a map.
4. good durability to withstand hours in the mountains during varying weather conditions, from rainstorms to the extreme cold but also environmental changes like river crossings, for example.
5. a comfortable fit for usage over many hours, especially important if you have small wrists and don’t want to be carrying a heavy weight around with you for hours on end.
6. a barometer to help us know our current elevation and when a potential lightning storm may be on its way so that we can take cover if necessary.
7. a good software platform for analyzing activity data and tracking our training performance over time.
8. the ability to play music, ready for when you need that pain-cave pick-me-up!

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1. Garmin Fenix 6 Series (6S, 6 & 6X – Pro & Sapphire Editions) [BEST OVERALL]

Before getting into the features of each individual variation of the Garmin Fenix 6 series (there are A LOT), I’d like to point out that the Garmin Fenix 6S Pro variant is the watch we rate as the best GPS watch for runners, due to its small size, impressive feature set, and good price point. The difference between the Fenix 6S and 6S Pro is that the Pro has additional features including Music, Maps, and WiFi.

Some may like to upgrade this setup further by opting to add the sapphire scratch-resistant lens to the 6S Pro Sapphire. The sapphire lens will undoubtedly increase the durability and lifespan of your Fenix watch because once a screen is overly scratched, it can be difficult to distinguish data that is displayed on the screen.

Garmin has made so many options available that it can be a bit daunting knowing which Fenix GPS watch to choose for running with, so I thought I’d quickly share my choice of setup which in my opinion makes this the best GPS watch for ultrarunning.

The Best GPS Watch For Trail Running – Garmin Fenix 6 series Key Features

Battery Life

There are differences in battery life which you should be aware of when choosing a watch from the Garmin Fenix 6 series. See below for each watch and its corresponding battery life in each of the available modes.

FENIX 6S – Smartwatch: Up to 9 days / GPS: Up to 25 hours / Max Battery GPS Mode: 50 hours / Expedition GPS Activity: 20 days / Battery Saver Watch Mode: 34 days

FENIX 6S PRO – Smartwatch: Up to 9 days / GPS: Up to 25 hours / GPS and Music: Up to 6 hours / Max Battery GPS Mode: 50 hours / Expedition GPS Activity: 20 days / Battery Saver Watch Mode: 34 days. – Because of its smaller case size (42mm), the Fenix 6S Pro is perfect for women or men with small-to-medium wrists who don’t plan on running for more than 25 hours in one go. A smaller/lighter GPS watch also means it will remain comfortable for much longer than a heavier alternative. See below to find the best price for the Garmin Fenix 6S Pro.

FENIX 6 PRO– Smartwatch: Up to 14 days / GPS: Up to 36 hours / GPS and Music: Up to 10 hours / Max Battery GPS Mode: 72 hours / Expedition GPS Activity: 28 days / Battery Saver Watch Mode: 48 days. – This is the mid-sized watch and arguably the most popular because of it. See below to find the best price for the Garmin Fenix 6 Pro.

FENIX 6X PRO – Smartwatch: Up to 21 days / GPS: Up to 60 hours / GPS and Music: Up to 15 hours / Max Battery GPS Mode: 120 hours / Expedition GPS Activity: 46 days / Battery Saver Watch Mode: 80 days.This is the watch for the most serious of athletes that want the best realtime training insights available. This is the larger watch but it has the best battery life. See below to find the best price for the Garmin Fenix 6X Pro.

HR Monitor

The on-wrist heart rate monitor is accurate and more comfortable than a chest strap. This even works underwater, so you can track your heart rate while swimming, now thats impressive.

Pulse OX Sensor

For altitude acclimation or sleep monitoring, a Pulse Ox2 sensor uses light beams at your wrist to gauge how well your body is absorbing oxygen. Super useful when running at altitude or when used as an extra indicator for current fitness levels. ALL Fenix GPS watches now include this as standard, awesome!

Navigation

The navigation features are excellent and in my opinion, the best in class. High resolution, color TOPO maps featuring trend line popularity routing to help you find and follow the best paths. This, in my opinion, is a fantastic feature that blows the competition away in terms of navigation. I love how easy it is to set up a course/route and then send it to the watch, ready for following during your run. Then when the route is displayed back to you on the watch, the detail is so incredible. I love to explore new routes/trails, so being able to see the trails lines on the watch map that you shouldn’t take, makes it so much easier to see the ones you should, hence reducing the chances of getting lost.

Durability

Rugged design especially if you opt to upgrade to a sapphire watch face. It will cost you an extra $100 but your watch face will be more resistant to scratches than other materials.

Altimeter, Barometer, Compass, and Actionable Features

For accurate altitude/elevation tracking and weather tracking. When following a programmed course, you can set a real-time ‘ghost’ competitor which shows a marker on the watch to motivate you to keep up with it, this can even be your fastest time running that route, very cool. When navigating a course you can also see the route profile with elevation gained and elevation remaining. I love this for being able to quickly visualize how much climbing I have left to crank out.

Water resistance

10 ATM (100m)

Music

You can store up to 2000 songs on the watch which means you won’t need your phone with you to play music.

Software

Garmin Connect is a fun platform to store your runs on. There’s a wealth of data stored there so you can stick to built-in training plans and compete against friends. It can be used to track daily steps, heart rate, and sleep data too, provided you wear the watch all day. I like to automatically send my runs to Strava though as I have used the platform for a long time and have many friends on there.

Those features are just some of the reasons why I rate the Garmin Fenix 6 Pro to be the best GPS watch for trail running.

Best deals for Garmin Fenix 6S Pro Running Watch

Best deals for Garmin Fenix 6 Pro Running Watch

Best deals for Garmin Fenix 6X Pro Running Watch

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2. Coros Apex – [EDITOR’S CHOICE & Most Affordable]

Coros is a lesser-known brand that is making serious waves in the trail running and Ultrarunning scene with the Coros Apex GPS Watch in particular [FULL REVIEW HERE]. The list of Coros pro athletes is impressive to say the least, including runners such as: Dom Grossman, Sally McRae, Timothy Olson, Cody Reed, Hayden Hawks, Camille Herron, Tim Tollefson, Adam Campbell, Paula Findlay, Magda Boulet, Jordi Gamito and Hillary Allen.

Weight: 50.8g/55.3g

Full GPS: 25/35hours

Price: $300/$350

The APEX is the only Coros watch to offer two different watch sizes, 42mm and 46mm. This is great news for those who want plenty of features but don’t want to wear a bulky watch due to small wrists.

The APEX tracks course, speed, time, pace – all the usuals, as well as elevation gain / loss, weather (via the built-in barometer) cadence, calories and heart rate. From this data the watch also calculates estimated fitness levels including VO2Max and lactate threshold, and the efficiency of your aerobic and anaerobic training activity.

I really like the simple clean look of the APEX because it means you can wear it to work without it standing out too much. It’s also great knowing that you have the power on your wrist to do those impromptu long runs when you need to though. There’s also a sapphire glass screen for everyday and extreme protection.

Watch Size: 42mm/46mm

Waterproof: 100m

The APEX is able to accurately determine your overall effort, broken down into stamina level (0-100) and training effect (0-6). This means COROS Trainer can notify you it’s time to rest up or to pick up your training. Based on the effort level and training history, you can then see an advised recovery window before you begin your next activity. This is available for Interval, Aerobic, and Anaerobic Training modes. Once you’ve finished your workout, the COROS App will give you a complete graphical analysis of your training including VO2 max, recovery advisor, threshold pace, last-7 days training load, personal fitness index and plenty more. Additionally, you can connect to your favorite 3rd party applications such as STRAVA and TrainingPeaks and automatically upload your workouts.

Battery Life for the 42mm size

Reg. use: 24days

Full GPS: 25hours

UltraMax: 80hours

Battery Life for the 46mm size

Reg. use: 30days

Full GPS: 35hours

UltraMax: 100hours

Routes can be uploaded and displayed on a grid as a bread crumb trail with real-time information on heading and elevation. It also gives you alerts to help you get back on course, should you go off track.

In UltraMax mode, the battery will last up to 100 hours using GPS. While using normal mode will yield up to 35 hours. This is easily enough for most ultramarathons.

Having an extremely competitive price-point, the choice of two lightweight watch sizes, a very impressive battery life, on-wrist HR, and many other features makes the Coros APEX our top pick for trail and ultrarunning.

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RELATED LINKS:

• Coros Apex Review: The Ultimate GPS Watch For Trail Runners?
• Coros GPS Watches Compared: Which one should you buy?

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3. Suunto 9 Baro

Suunto 9 Baro Key Features

Battery Life

25 hours of battery life with Performance mode, 40 with Endurance, and up to 120 hours with Ultra mode. The Suunto 9 Baro has great battery life and should be considered if you intend to run the middle of the pack ultra races of 100 miles or more.

HR Monitor

The Suunto 9 Baro also has an on-wrist heartrate monitor.

Navigation

Navigation is available but not as feature-rich as the Garmin Fenix 6 Pro series. I find myself often taking the wrong turn when running new routes because of the lack of detailed maps on the watch.

Durability

Rugged design with a sapphire watch face. Suunto really know how to make watches that last!

Barometer

For accurate altitude/elevation tracking and weather tracking.

Water resistance

100m

Music

No music available so you’ll have to rely on your mobile phone or music device. I prefer to save phone battery life for emergencies so will end up not listening to music during an ultramarathon unless my watch has the capability.

Software

Movescount is a pretty feature-rich although the options for visualizing data are not as comprehensive as Garmin Connect. I have noticed that transferring moves from the watch to the platform on a mobile device is slower than the Garmin equivalent. I notice more downtime with their servers too which means you cannot view your activity until the system comes online again. frustrating when you want to analyse that hard training run. Having said this, the platform is sufficient but I’d love to see more stability improvements.

Best deals for Suunto 9 Baro Running Watch

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4. Polar Grit X

The Polar Grit X is a watch that has almost all the features you could possibly want for trail running and ultrarunning, and for such a low price-point, you can see why it’s getting so much attention within the trail running community. If you’re not familiar with Polar, they’re a company who like to put a strong focus on heart rate training, which is important as your heart is the only real constant in knowing how fit you are at any given point in time. Our heart is our engine, and we are all unique, so it makes sense to train by heart rate as opposed to someone elses training plan, if you want to personally get better/stronger/faster.

Weight: 64g

Full GPS: 40 hours

Price: $429.95

Let’s start by mentioning some of the features that make this watch stand out, firstly you have a very long battery life of 40 hours (with GPS) which is extremely good for such a low price. Then you have a watch that looks good enough to be worn for everyday life too (not just running), and I love how much attention Polar puts on heart rate training. They go one step further by actively tracking your sleep, provided you wear it to bed at night.

Good quality sleep is key to fast recovery after running; Polar knows this, and it’s why they want to help you get deeper insights into how how heart responds after training while you sleep. With this data you can see how well you’re recovering after exercise, and with it, alter your training to help improve the quality of your sleep.

Some other great features include FuelWise which aims to help you know when the best time is to refuel during a run, because the Polar Grit X is smart enough to know what fuel you’re burning the most; whether it’s carbs, protein or fats. The other feature I really like is ‘Hill Splitter’ which gives detailed data about your performance on the uphill and downhill sections of your session – for anyone who enjoys getting climbing steep hills or mountains, this watch will make those efforts even more enjoyable to sweat for. Learn more about all the smart Polar Grit X features here.

Polar Grit X Key Features

Battery Life

The Polar Grit X has 40 hours of battery life in training mode (GPS and wrist-based heart rate) or up to 7 days in watch mode with continuous heart rate tracking. I like that there are multiple power save options available too. 40 hours is the sweet spot for many mid range ultra races.

Watch Size: 47mm

Waterproof: 100m

HR Monitor

The HR monitor on the Polar Grit X is very accurate.

Navigation

The only downside to this Polar Grit X in my opinion is the limited Navigation software/features. It is available but not as feature-rich as the Garmin Fenix 6 Pro series. You don’t really get a map on screen when following a route, instead, you get a line to follow with turn notifications which leaves margin for error in choosing the wrong route when navigating trails that may be close together.

To create routes you’ll have to step outside of the Polar environment and use another service called KOMOOT. This unfortunately leads to a bit of a clunky experience when you want to create and follow new trails. If you’re not interested in running/exploring new routes in areas you’re unfamiliar with, then this won’t be an issue for you.

Durability

The Polar Grit X has passed several MIL-STD-810G tests, including extreme temperatures, drop and humidity which makes it a very reliable tool to have with you when you’re in the mountains.

Barometer

For accurate incline, ascent, and altitude tracking.

Water resistance

100m

Music

No music available so you’ll have to rely on your mobile phone or music device. I prefer to save phone battery life for emergencies so will end up not listening to music during an ultramarathon unless my watch has the capability.

Software

The Polar Flow online software and smartphone app is actually really well constructed and easy to use. It’s a please to use to track your training in a nice visual manner.

Best deals for Polar Grit X Running Watch

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Suunto vs. Garmin vs. Coros watches for Ultrarunning Summary

In summary then, If you’re looking for an all-round performer that has feature-rich navigation, On-wrist HR + Pulse OX, a long battery life of up to 50 hours with GPS, and a very comprehensive online platform to store and analyze your activities then the Garmin 6S/6 Pro is my recommended choice. If on the other hand, you don’t think you need all those features, and would prefer a less expensive, rock-solid watch that has an impressive battery life and a simple interface, then the Suunto 9 Baro or the Coros Apex are both great choices.

I really hope you enjoyed reading this Best GPS Watches for Ultrarunning and Trail Running Buyer’s Guide. If you did, please give it a share, and if you have any questions at all, please leave it in the comments below, I love talking about running gadgets! 🙂