Garmin Forerunner 945 review

Professional analysis for any stat-obsessed athlete, with an intuitive user interface and great battery life

Garmin Forerunner 945
(Image credit: Emma Silversides)
Cycling Weekly Verdict

Garmin's Forerunner 945 is designed for those who want to get the very best out of themselves across a range of activities. It makes professional analysis of training and recovery accessible to users, and guides them to optimise performances based on personal data. Recharge is rapid and battery life is impressive. Both the watch and app are intuitive and reliable. With a range of extra functions, such as offline music and contactless payments, it's difficult not to get excited about this watch. This is an outstanding bit of kit that is undoubtedly worth every penny/cent of its £499.99/$599.99… don’t people spend hundreds per year on personal trainers? Here’s one that will be on your wrist 24/7.

Reasons to buy
  • +

    Long battery life

  • +

    Quick recharge

  • +

    Seamless syncing with app

  • +

    Intuitive interface

  • +

    Accurate sensors

Reasons to avoid
  • -

    So much functionality that it might not be used to its full potential

  • -

    Will need to buy extras if you are to use it to its full potential on the bike

You can trust Cycling Weekly. Our team of experts put in hard miles testing cycling tech and will always share honest, unbiased advice to help you choose. Find out more about how we test.

If your physical pursuits are varied off the bike, as well as on it, the Garmin Forerunner 945 GPS smartwatch is an investment that you won’t regret; it’s a coach and analytical computer at once.

It can track a whole host of activities: it would genuinely take months to exploit all the activity profiles available and explore the analysis of each in depth. 

The Forerunner 945 was first released over two years ago and has undergone some minor refinements since then. For me, it's no surprise that a new model hasn't been released; this one ticks every box and does what it does exceptionally well.

Garmin Forerunner 945: what's in the box

The main body of the Forerunner 945 is a combination of a 'fibre-reinforced polymer' case and Corning Gorilla Glass DX lens. Despite plenty of rough handling, the watch face isn’t showing signs of wear - I’ve been using it uninterrupted for two months.  

The silicone strap, which is hinged at the watch face, is perfectly flexible and very comfortable. It’s designed to a fit wrists with a circumference of 130-220 mm. The whole thing weighs in at 50g.

There is a spare loop in the box. I swapped it for the one on the strap quite quickly. It has a tab on it (that the one on the strap doesn’t) to prevent it from slipping; the tab sits in any one of the holes on the watch strap.

The USB charging cable is 0.5m. Garmin sell spare 0.5m and 1m cables.

Charging and battery life

The Forerunner 945 would consistently go from flat to full in 75 minutes on a mains charger; it took a little longer from my computer. There is a battery icon at the top of the watch face with a graphical capacity, but no percentage. You can see this with a prolonged press of the ‘up’ button.

The battery life obviously depends heavily on what you ask of the watch. If you simply use it as a smart watch – with no demands on music or GPS for activities – it can last two weeks. I have been averaging a charge every 6-7 days. That’s with at least one session a day of cycling or running, so between 8 and 12 hours of activity. If you use both music and GPS, you’ll be charging much more frequently.

Core features

The default watch face is what you see in the photos. Unsurprisingly, if you don’t like it you can customise it, changing the data fields too or even creating your own face via the Connect IQ Store.

The watch tracks users’ day-to-day activity, so steps, stairs, heart rate, sleep and pulse ox. You can scroll through all this at any time and use all the widgets to get deeper insights. There are even more apps and widgets on the Connect IQ Store if what’s there doesn’t satiate you.

All of this data syncs with the app (or website) and you can view it there too. You really won’t be left wanting for any piece of day-to-day data. If you are used to a third-party training or healthcare platform, it’s possible to share your data with them.


(Image credit: Emma Silversides)

The sleep tracking metrics are no less comprehensive than any other field, although I am personally sceptical about the accuracy of any device’s capability here. I've been concurrently testing another smart watch and they can disagree wildly about the quantity and quality of sleep from one night to the next. 

The Forerunner 945 constantly tracks heart rate (every second) and syncs this with the app. While the overall accuracy has been good, there are some minor issues on the bike – more on that later. I'd say it's just like the sleep data – it’s a great guide, particularly for identifying over-training and tiredness, thus susceptibility to illness, but don't consider it set in stone.

Sleep data

(Image credit: Emma Silversides)

On the back of the watch, next to the green lights (which track heart rate), there’s a red light tracking pulse oximetry. It’s a pretty useless statistic for most mere mortals existing at sea level. If you are training at altitude, it’ll have its uses.

Like all smart watches, the Forerunner 945 will allow you to receive notifications. You can configure everything about them on the watch, including having notifications off during activities, and viewing via gesture or a button press for privacy reasons.

Getting sporty

Any keen cyclist or runner will be bathing in stats from the 945, and there’s a variety of disciplines within these sports - MTB, eBike, Cyclocross, Gravel Bike, Bike Commute and Bike Tour are just a few of the cycling ones. Other sports don’t get overlooked, they just get fewer metrics. So if you do any of the following, you can track a least some element of your performance using the profiles: Pool Swimming, Open Water Swimming, Hiking, Climbing, Skiing, Snowboarding, XC skiing, SUP, Rowing, Kayaking, Bouldering… this list goes on. The watch boasts some impressive features and analysis for golf too… sorry, I haven’t tested those.

The 945 can be used with wireless ANT‍+ or Bluetooth sensors. This covers a whole range of accessories – speed and cadence sensors, power meters, Shimano Di2 shifters, Varia lights and radars, tempe and footpods (of more interest to runners). It’s possible to connect multiple sensors at the same time, so if you have several bikes with different sensors it’s no problem, the watch automatically picks them up when they switch on. They are saved across the entire device, so not unique to one sporting profile. In the two months of testing, I’ve never once had a single issue with connectivity.

For any activity, you can customise the pages in that sporting profile. There are heaps of options for arrangements of (between one and six) data fields per page, and as many pages as you want. Standard screens exist for things like music, elevation, virtual partner and maps. I found three fields sufficient, but that’s personal preference in terms of ease to read and relevance for any particular session. 

In reality, none of this needs to be set up immediately; the Garmin is good to go out of the box and very intuitive to use. The buttons are subtly labelled too, I’ve loved this for familiarising myself with the watch. I’m concurrently testing a similar smart watch from another manufacturer and it really makes you realise how little things like this can make life easier.

The screen contrast is good; I never once felt like I was straining to read numbers in any light conditions. If running in the dark, the screen lights up when you lift your wrist to view the watch face.

I’d say at this point that, for cycling, it’s a really essential to buy the mount or the quick release kit. I didn’t get either to test so created an alternative, you simply can’t glance at the watch face, or easily and safely toggle screens with it on your wrist, particularly in winter gear. This inevitably means that if you want to track your heart rate, you’ll need a chest strap too.

Having the sensor on the wrist is surprisingly accurate. I had inevitable breaks in monitoring while cycling due to movement (accessing pockets, all-out sprints…), but not as many as I would have expected and never for long. I'd say I was testing in the 'worst case scenario' too; always in thick, long sleeves and gloves which can lift and/or shift the position of the watch.

Although I wouldn't count myself as a runner, I am currently starting to build back up follow a long period out of the sport. Right now, sessions involve a mix of walking and running, but the Forerunner 945 has offered great motivation. It'll flash up with performance percentage gains and the usual PB notifications on at the end of sessions – providing a welcome sense of progress.


Once you’ve finished and saved a session, the Forerunner gives immediate feedback with several pages of stats and lap breakdowns. It breaks down training benefits and suggests recovery. You can see here the data from one of my rehab runs, then some from a rainy endurance ride. 

All of this is synced automatically to the Connect App – via Bluetooth or WiFi – with it available to view there too. Likewise for third-party applications – I've been using both Strava and Training Peaks and the transfers have always been quick and haven't once failed. 

Feedback and advice

With all of the data that is being collected, Garmin is forming a picture of you as an athlete, producing continual analysis and advice. For instance, it's telling me that I'm gaining fitness with a stabilised load that's providing a good balance across my training zones.

All of this is available in the app too – some of it is less colourful and arguably not quite so easy to find – but that said, it can be easier to interpret. The time lines are definitely more palatable when viewed in the app. The bottom line is that comprehensive details is available at your finger tips.

It's possible to be guided by Garmin with training session suggestions. These will come up when you select the activity, before starting it. So if you want to plan training for the following day, it is possible. 

If you want more than basic guidance, you can make use of Garmin Coach to get adaptive training plans that feature guidance from expert coaches and free training plans that adapt to you and your goals. Workouts sync to your watch.