Garmin Forerunner 945 v Fenix 5: Garmin's sports watches compared

It's a sports watch showdown
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The Garmin Fenix 5 Plus and the Forerunner 945 couldn't look any different, but the two sports watches actually share a lot of similarities.

While the Fenix 6 is now on the scene, this is still relevant reading, as both the Fenix 5 and 6 are extremely similar devices, and there are plenty of deals to be had on the older generation.

But picking between these two devices is difficult. The Forerunner 945 packs in Fenix features and vice versa. They're two of the best watches we've run with, hit the trails with and got sweaty in the gym with. If you're weighing up which one might be the best fit for you, we're here to help.

Essential reading: Best Garmin watches to buy now

From design to battery life and those all important sports tracking features, here's the lowdown on how the Forerunner 945 compares to the outdoor watch beast that is the Fenix 5 Plus.

Read our full tests: Garmin Forerunner 945 review | Garmin Fenix 5 Plus review

Garmin Forerunner 945 v Fenix 5 Plus: Design

Garmin Forerunner 945 v Fenix 5: Garmin's sports watches compared

These two watches are really designed for two very different kinds of people. The Forerunner 945, like its predecessor the 935, is billed as Garmin's triathlon-friendly sports watch. The Fenix 5 Plus on the other hand is all about the outdoors. You can still track triathlons with it, but its bulkier, more durable frame is built to better withstand the elements.

Both the Fenix 5 Plus and the 945 feature 47mm cases and interchangeable straps, but the Fenix is around 1mm thicker. There's a weight difference too with the Fenix coming in at 86g and the 945 the lighter at just 50g. That's because you'll find a stainless steel or titanium bezel on the Fenix to add that extra layer of protection. These differences mean they will feel different to wear. The Fenix is by no means heavy, but if you want something more slimline, the 945 is the one to go for.

In the screen department, you're getting identical 1.2-inch, 240 x 240 resolution transflective colour displays. There is of course a smaller Fenix (5S Plus) and a larger model (Fenix 5X Plus), but all share the same screens. Garmin has opted against the kind of vibrant, colourful screens you'll find on smartwatches like the Apple Watch in favour of something that can offer good visibility in bright conditions and help prolong battery life so you're not charging it everyday.

Garmin Forerunner 945 v Fenix 5: Garmin's sports watches compared

If you're all about heart rate monitoring, Garmin packs all of its watches with its own Elevate optical sensor tech. The 945 though does include the latest generation Elevate setup, which should give you an overall slightly more reliable heart rate experience. Both support adding external heart rate chest straps and other additional sensors though if you don't trust what the wrist-based sensor is dishing out.

As is the standard with Garmin's watches, you're getting plenty of waterproofing here – so you can wear either in the shower and for pool and open water swimming. If you want to go a little deeper, the Fenix 5 Plus is safe to be submerged up to 100 metres while the 945 offers up to 50 metres. We imagine 50 metres should be sufficient for most who predominantly train in the water.

Garmin Forerunner 945 v Fenix 5 Plus: Sports tracking features

Garmin Forerunner 945 v Fenix 5: Garmin's sports watches compared

Garmin aims to offer a consistent experience across these two watches. So core sports tracking modes across both are running, cycling, swimming and golf. You've also got outdoor profiles for the likes of hiking, snowboarding and paddleboarding. Indoor workouts like rowing, stair stepping and treadmill running are covered along with an automatic rep counting feature for weight-based workouts. If you care about counting your steps and monitoring your sleep, these are both great at doubling as fitness trackers too. There's plenty of the same training and analytics features on both. Basically, you're well covered with both of these watches.

Read this: Pulse oximeters on wearables explained

On the sensor front, you've got GPS, GLONASS and Galileo satellite support for mapping your outdoor pursuits and useful outdoor sensors like a thermometer, compass and a barometric altimeter. The 945 includes the Pulse Ox sensor that is available on the pricier (and bigger) Fenix 5X Plus. That sensor is designed to offer richer sleep metrics, but also to offer useful insights for anyone that likes training at altitude. It uses an optical, light based tech to draw that information to hopefully keep you safer when you're hiking up a mountain or trail running at high elevation.

Garmin Forerunner 945 v Fenix 5: Garmin's sports watches compared

If you care about mapping, Garmin has brought the topographical maps that first debuted on the new Fenix range to the 945. That joins standard Garmin navigation features like Back to start, UltraTrac mode, TracBack and of course point-to-point navigation.

We've already spoken about heart rate sensors, with both offering identical features including working in heart rate zones, delivering heart rate alerts and the ability to conduct HRV stress tests, although you need a chest strap to do the latter. That chest strap can also unlock an additional feature on the 945 you don't get on the Fenix, and that's viewing your respiration rate. It's not a dealbreaker we imagine for most, but it's a nice piece of extra data to have during your workouts.

Garmin Forerunner 945 v Fenix 5 Plus: Smartwatch features

Garmin Forerunner 945 v Fenix 5: Garmin's sports watches compared

Garmin's smartwatch powers continue to improve and with both the 945 and the Fenix, you are pretty much getting the best of what it has to offer on this front.

Read this: Best Garmin watch faces to download

You're well covered on the connectivity bases with Wi-Fi, Bluetooth and ANT+ all in tow. Both will work with Android and iOS smartphones too though pairing up with an Android will let you respond and act on notification messages that land on your watch screen.

Along with that notification support you're getting a built-in music player and offline playlist support for Spotify and Deezer, which you can't do on something like the Apple Watch. You can also control music playing on your phone if you don't want to leave it behind, and view phone data on dedicated screens, including calendar appointments and the weather. If you care about payments, you're in luck here. Both come with Garmin Pay to unlock that functionality.

Support for Garmin's Connect IQ platform means you also have the ability to download additional apps, watch faces, data fields and widgets to make the devices better tailored to the activities you like to do.

Garmin Forerunner 945 v Fenix 5 Plus: Battery life

Garmin Forerunner 945 v Fenix 5: Garmin's sports watches compared

Garmin never scrimps on battery life and these two watches offer some of the most impressive battery performances we've seen on a sports watch. The 945 offers up to two weeks in smartwatch mode, up to 10 hours using GPS tracking and music features, and up to 36 hours just using GPS.

The Fenix 5 Plus in comparison offers up to 12 days in smartwatch mode, up to 18 hours in GPS tracking mode, 8 hours with GPS and music and up to 42 hours in UltraTrac mode. The 945 does also have that UltraTrac mode too if you're willing to sacrifice tracking accuracy for the ability to track your entire activity.

Our experience living with both watches is that they really can go the distance with their full gamut of features in use. We'd be inclined to say we were more impressed with the 945 in this department for its staying power, but we don't think either watch will disappoint.

Garmin Forerunner 945 v Fenix 5 Plus: Price

This will no doubt be a factor in your decision choosing between these two watches. With the 945, you're looking to pay , or for the Tri Bundle, which includes the additional heart rate monitor chest straps.

If we compare that to the standard Fenix 5 Plus, that comes in at . So they're not too dissimilar in pricing. If you compare to the top end Fenix 5X Plus, the price jumps up to and there's a bigger difference in how much you're going to have to pay. It's actually what you'd pay for the 945 with the additional chest straps.


First we'll say that we've enjoyed using both of these watches a lot. Both received excellent 9 out of 10 scores in our reviews and they both get our seal of approval. If you're trying to choose between the two, we think there's a few crucial factors to look at here.

Design is the first. If you plan to use your watch for rugged outdoor activities and you like the look of a big watch, the Fenix is the one to go for. Prefer keeping things more compact? Go for the 945. It's more sporty in look, but it's one of the most comfortable sports watches we've strapped on.

It's hard to separate them on sports tracking and training features, though you will get a few more richer training and analysis extras on the 945 simply because it's the newer device. Will these significantly impact on your experience? For most, probably not.

If you're looking for big battery life, we think the 945 is a slightly better performer, though there's not a lot between them. The 945 is our current running watch fave so that's the one we'd recommend, but the Fenix collection is definitely going to appeal to anyone looking for something with a more statement feel to it.


How we test

Michael Sawh


Michael Sawh has been covering the wearable tech industry since the very first Fitbit landed back in 2011. Previously the resident wearable tech expert at Trusted Reviews, he also marshaled the features section of

He also regularly contributed to T3 magazine when they needed someone to talk about fitness trackers, running watches, headphones, tablets, and phones.

Michael writes for GQ, Wired, Coach Mag, Metro, MSN, BBC Focus, Stuff, TechRadar and has made several appearances on the BBC Travel Show to talk all things tech. 

Michael is a lover of all things sports and fitness-tech related, clocking up over 15 marathons and has put in serious hours in the pool all in the name of testing every fitness wearable going. Expect to see him with a minimum of two wearables at any given time.

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