​Garmin Forerunner 45 review

This stripped back watch belies its low price
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Garmin Forerunner 45
By Garmin
The Garmin Forerunner 45 is a brilliant budget watch that offers more detail and better performance than anything else in its price bracket. You’d struggle to pick up ageing generations of rival watches for less, and Garmin has relentlessly added top-end features across its lineup, with this Forerunner benefitting hugely. It’s slim, comfortable and fairly good looking to boot. For 90% of runners who aren't bordering ultra marathon distances, it comes highly recommended.

  • Slim and light
  • Packed with features
  • VO2 Max
  • Shortish battery life
  • Low resolution screen
  • Optical HR not perfect

Garmin’s back with the Forerunner 45 – the new entry level running watch for those who want a dedicated GPS tracker but are less concerned about Olympian levels of biometric data.

The Forerunner 45 clocks in at , which, as Garmin’s lowest priced entry, might not seem hugely affordable, but still ranks among the lowest cost running watches on the market. It goes head-to-head with devices like the Polar Ignite and Fitbit Ionic – both with its diminutive size and powerful features – and is a worthy alternative to the powerful Forerunner 245 just without the advanced data,

Essential reading: Best Garmin sports watches

Garmin is trickling down features across its range and you get more for your money than ever before: heart rate, smartwatch notifications – even VO2 Max is all here.

But how does it all work – and is it the right running watch for you? We’ve been running with the Garmin Forerunner 45 for a few weeks, and have been hugely impressed. Here’s why.

Garmin Forerunner 45: Design

​Garmin Forerunner 45 review

The first thing to note is how slim the Forerunner 45 is. It’s a new 42mm case, but it’s seriously svelte. In comparison to the boxy Forerunner 35 it replaces, it’s night and day in terms of styling. And it weighs just 32g, so it’s hardly noticeable on the wrist. That’s not something many Garmins can boast.

If you want to go even smaller, there's also the Garmin Forerunner 45S, which shrinks the design down to a 39mm case. It's still the same price and you're getting all of the same features too.

The standard Garmin five-button setup is here, with backlight control and menu up/down on the left, and the menu and back buttons to the right. It’s easy to control – or, maybe because Garmin has used the same OS and controls for so long now, it’s second nature.

The screen is colour – just. It’s the same low-power, 208 x 208 LCD you’ll find on every other watch, which does the job of being clear and readable at all times. It’s basic, but it does the job. It’s no Apple Watch, though, let’s be clear on that.

There’s a silicon strap – available in orange and black – which clips with a buckle and a loop. We did find the loop a little fiddly, and it often slipped round to leave the strap flapping around. A minor irritation.

Read this: Cheap Garmin deals

Garmin Forerunner 45: Features

​Garmin Forerunner 45 review

We’re going to talk about sports tracking in the section below, so, as we run down features, let’s just say it’ll track your run.

However, there are a few extras on board. The Garmin Forerunner 45 boasts smartwatch style notifications – so you’ll receive calls, WhatsApps, SMS, Facebook notifications, Candy Crush reminders, all to your watch. If you like that sort of thing.

Then there are fitness tracking elements, too, which make a bit more sense on a watch that’s this discreet and comfortable. You’ll get steps, calories, active minutes for the week, as well as heart rate, stress levels and body battery – a metric that tracks how ready you are for your next training session.

The heart rate elements are quite strong, and as well as tracking your heart rate over a four-hour period, the Forerunner 45 will also log resting heart rate over the last seven days. What’s more, there’s an abnormal heart rate alarm too – which defaults to 100bpm while you’re at rest.

While not able to access the full gamut of Connect IQ apps – which offers more premium Garmin watches new sports modes – you can download and select new watch faces from the online store, which is pretty nice.

Garmin Forerunner 45: Sports tracking

​Garmin Forerunner 45 review

Now onto the real deal: GPS sports tracking. The Forerunner 45 is primarily a running watch, which we’ll focus on here. But there are modes for running and cycling (which use the GPS to track distance), and indoor track, treadmill, elliptical, cardio and yoga.

Don’t get too excited, there aren’t incredible new metrics never seen before on a wearable device – you just get time, heart rate and zones, and estimated distances where appropriate.

So, running. The first thing is how long the GPS takes to lock on. We’ve not been made to wait ages, thanks to a wide range of satellite support, including Russian GLONASS.

Data screens

​Garmin Forerunner 45 review

The feedback you get during a workout is much more minimal than on more advanced Garmin watches. You only get two screens of data – one of pace/time/distance and the other with heart rate/heart rate zone/calories.

However, you can create custom data screens and add cadence, lap times and lap distances. You'll want to use that if you're taking your Forerunner 45 to the track – as current lap data isn't shown by default.

And while budget Garmin watches have often stripped back on the advanced metrics, there are some surprise additions on the Forerunner 45. After a run, you get a heads up on your current VO2 Max level – which is really welcome for someone who’s spent time with high-end watches, and it’s one of our favourite running stats.

There’s no VO2 Max screen as you’ll find on other, more expensive Garmins, but it populates the performance tab in Garmin Connect, so you can check there for details.

Forerunner 45: Heart rate accuracy

​Garmin Forerunner 45 review

HR comparison: Forerunner 45 (top) vs Fenix 5 Plus and chest strap

The Forerunner 45 uses the Garmin Elevate optical sensor, and, as such, there’s no real surprise that heart rate accuracy is decent for runners – but with limitations.

On several runs it was locked to heart rate strap, producing identical data. You can see from the graphic above that the two runs were almost identical apart from hill sprints which exposed the limitations of the optical sensor.

Sudden bursts of HIIT left the 45's sensor for dead. Starting at 116bpm (mid-run) and sprinting uphill to Max HR the optical sensor stuttered slowly to 160bpm and got stuck there – while the chest strap rose to 180 and returned back.

It’s not a problem that's exclusive to Garmin – it's pretty standard. But you’ll need to be aware of it if your training is HIIT-focused.

That’s not to say that the Garmin is incapable of reaching Max HR. When running up the dreaded Crystal Palace Hill, both sensors clocked 170bpm and glued together for the whole run, simultaneously recording a push to the top where bpm rose to 185 (you can see just before the marker on the above charts).

The gradual increases you’d find in a race or training run are more than adequately tracked – but explosive HITT from a standing start, well, there isn’t a wrist-based optical sensor out there that can handle that, and the Forerunner 45 is no different.

The Forerunner 45 can connect to ANT+ chest straps, so there’s no reason to avoid – just pick up a strap for your HIIT sessions.

Forerunner 45: Garmin Connect and battery life

As you’d expect, the Forerunner 45 feeds into Garmin Connect to store your data. This isn’t the place to really discuss the merits of the platform, but it’s a great spot for collecting running and sports data as well as fitness tracking.

Garmin Connect is still a bit of beast, but if you love getting into the detail, there’s a lot to like. And you’re not just limited to Garmin Connect, either. Our Garmin account is locked to Strava, which we prefer for viewing data and is a much more social experience.

In terms of battery life, the slimmer case makes a big impact, in comparison to the likes of the Fenix 5 Plus and Forerunner 945. Garmin states a week of battery life with 13 hours of GPS, and that seems spot on from our extended testing period.

How we test

James Stables


James is the co-founder of Wareable, and he has been a technology journalist for 15 years.

He started his career at Future Publishing, James became the features editor of T3 Magazine and T3.com and was a regular contributor to TechRadar – before leaving Future Publishing to found Wareable in 2014.

James has been at the helm of Wareable since 2014 and has become one of the leading experts in wearable technologies globally. He has reviewed, tested, and covered pretty much every wearable on the market, and is passionate about the evolving industry, and wearables helping people achieve healthier and happier lives.

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