Both of these Forerunners are aimed at the kind of runners and sports lovers that are starting to get a bit more serious about the metrics they want to see - but also probably don't (or can't) spend big on a top end Garmin like the Forerunner 945 or the Fenix 5.
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Whether you're thinking about making the upgrade from 235 to 245, or you simply want to know which one should be your first running watch, we've lived with both to help make that decision easier for you.
From design to smartwatch features, we compare the two Forerunners to help you choose.
Garmin Forerunner 245 v Forerunner 235: Design
Like most wearable companies, Garmin's aim is to put its cutting-edge tech into smaller and lighter watch designs. So it's perhaps no surprise to find out that in the 245 you're getting a watch that sits slightly smaller on the wrist than its predecessor. The 245 features a 42mm case, while the 235 has a larger 45mm case. The 235 is actually slimmer than the 245, but it's hardly noticeable.
The circular screens are essentially the same size and use the same transflective display technology to offer strong visibility without sapping battery life. The resolution has been bumped up a notch on the newer 245, however. Both use interchangeable watch bands (the 20mm kind) and you're getting the same 5ATM (up to 50 metres) waterproof rating so you can take them swimming.
Around the back of the watches is where you'll find Garmin's Elevate heart rate sensors. With the 235 being the older of the two, you're getting the first generation of that heart rate tech while the 245 uses the latest sensor. We found the 235 wasn't the greatest performer for high-intensity heart rate workouts, while things are bit more reliable with the 245. But you do have the option with either to pair an external heart rate monitor chest strap should you want to ensure the highest fidelity available.
Ultimately, these are two very sporty-looking watches with plastic bezels and silicone bands. If you want more color options, then the 245 is the one to go for, but you do have that option to change the bands on both if you want an extra splash of color. If you're after something with a more stylish exterior then you'll need to look at the pricier Forerunner 645. We'd be inclined to opt for the smaller 245, but there's certainly not a lot wrong with the 235 in the design department.
Garmin Forerunner 245 v Forerunner 235: Sports tracking features
So, what can you track with these two watches? Let's start with the newer 245. Core modes are running, cycling and swimming (pool only). You're also getting the ability to track indoor activities like indoor rowing, and there's automatic rep counting for strength training, though based on our experience, the latter is not great. You're also getting 24/7 activity tracking with stress tracking and Garmin's new Body Battery feature included, which you don't get on the 235.
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The 245 has additional sensors which unlock features for outdoor lovers, like the onboard compass that offers navigation features including Garmin's TracBack feature and leaving a bread crumb trail in real time. There's also the new Pulse Ox sensor, which offers richer metrics for sleep and when you're working out in elevated terrain.
The 235, on the other hand, focuses on running and cycling tracking and offers more limited navigation features. You don't have the option to add advanced running metrics like you can on the 245, although that does require the additional Running Dynamics Pod to do that. You do though get GPS and GLONASS sensors to ensure tracking accuracy is up to scratch, as well as the accelerometer sensor for tracking indoor activities and the onboard fitness features.
Beyond sports tracking, you're also getting a raft of training-centric features here too. It's generally the same across the aboard aside from the Training Status, Load and Effect insights you do get on the 245. These insights are drawn from your workouts to give you a better idea of your current state of fitness and help determine whether you're in good shape to take on your next workout.
If you're very much focused on tracking and tracking alone, then the 235 will certainly serve you well. It does the basics right and still gives you some of those more advanced metrics. But the 245 does take that up a notch. For those thinking more seriously about training and would appreciate the extra navigation features, the 245 is the one that's going to appeal.
Garmin Forerunner 245 v Forerunner 235: Smartwatch features
Garmin realises that people want more smartwatch features and slowly but surely it's been rolling out more of that functionality across its watch range.
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The 235 launched in 2015, but even then the Android and iPhone-friendly watch was capable of letting you view notifications, calendar appointments and weather forecasts. It will also let you control music being played on your smartphone and does have Connect IQ support, so you can download additional apps, widgets, watch faces and data fields.
The 245 does all of that too but does add one big feature: a built-in music player. That means you can load on your own music to the watch and playlists from supported streaming services like Spotify and Deezer. Those features are available on the 245 Music model, which is more expensive than the standard 245 (more on that below).
If you really want those music features, there is only one option to go for. Aside from that, you'll be getting largely the same experience here.
Garmin Forerunner 245 v Forerunner 235: Battery life and price
You'll be glad to hear that battery life is big deal for Garmin on all of its watches and that doesn't change with the 235 and the 245.
How far that battery takes you depends on what features you tap into on a daily basis. The 245 promises up to 7 days in smartwatch mode and 24 hours in GPS mode. The 235 offers 9 days in smartwatch mode but just 11 hours in GPS mode.
As we said, features like music playback and heart rate monitoring will dent battery life, especially with music streaming on the 245. For a week's worth of training, you should be good with either of these watches.
In terms of pricing, the 235 comes in at ¬£199.99, but it can be found for less on retailer sites like Amazon. The 245 comes in two different models; the standard and music editions. The standard 245 will set you back ¬£249.99. When you add music into the equation, that does jump up significantly to ¬£299.99.
So we've outlined the key differences and similarities between these two Forerunners. We'll conclude by saying you shouldn't disregard the 235 simply because it's the older device. It's still a solid performer and if you can get it for less than its usual ¬£199.99 price, it's a really good option for someone that's starting to get a serious about their sports tracking.
The 245, on the other hand, offers more the smartwatch features that Garmin has introduced to its Forerunner range over the last 12-18 months and is the better looking watch to wear. It offers a nice mix of smart and sports features, and it's a good option if you're not ready to step and spend big. If you don't care about the music too, go for the standard 245 and you'll still get yourself one of the best watches out there.