Garmin Forerunner 255 vs 245: how the two running watches compare

2022-06-04 01:52:49 By : Ms. Nicole Jiang

The Forerunner 255 updates the popular 245 which has been around for more than three years now. It makes a great watch even better. The 255 has just appeared on Garmin’s website. But pretty much all of the info on the device was already known.

The new runners’ wrist-piece comes with some handy upgrades over its predecessor – along with a few different options for purchase. We have no doubt this watch will also prove to be a popular seller. It might not have all the bells and whistles of the high-end Forerunners, but it offers plenty for the money.

Essential reading: Top fitness trackers and health gadgets

Garmin Forerunner 255 vs 245 – which should you choose? Should you upgrade? Here’s how the two running watches compare.

Garmin Forerunner 255 and 245 come with the same overall general appearance. Both are circular in design, like the recent crop of all Forerunner watches. Both also sport five physical buttons, three on the left and two on the right.

But there are some very important design differences to be aware of which make the 255 stand out from the 245. For starters, you now get two size choices.

You can pick up the Forerunner 255 in a choice between a 45.6 x 45.6 x 12.9 mm case and a 41 x 41 x 12.4 mm case. The first has a 1.3 inch Transflective MIP display with 260 x 260 pixel resolution. The second has a 1.1 inch Transflective MIP with 218 x 218 pixels.

For comparison purposes, the Forerunner 245 only comes in a single 42.3 x 42.3 x 12.2 mm case size. This packs a 1.2 inch Transflective MIP screen with 240 x 240 pixel resolution. This means that Garmin has slightly increased the bezel size on the Forerunner 255s. Strange decision.

All of these are fairly lightweight timepieces. Unsurprisingly, the heaviest of the lot is the Forerunner 255 coming in at 49 grams. Both the Forerunner 255s and 245 come in at around 10 grams less.

The build remains unchanged. The case is made of fiber-reinforced polymer and this is attached to a removable silicone band. The display is protected by Corning Gorilla Glass 3. Also unchanged is the water resistance. At 5 ATM there is no need to improve it.

You do, however, get a different choice of colours. The 255 is offered in a choice between Slate Grey/Black, Dark Blue/Black for non-Music and Black, Stone White/Black for the Music edition. The 255s offers the same set of colours for the Music version and Light Grey/Black, Dusty Pink/Black for non-Music. Finally, the 245 Slate Gray and Berry options for the regular variant and Black, White and Aqua for the Music one.

Some important differences can be found under the hood, too. One of the important ones is the inclusion of a barometric altimeter on Forerunner 255 and 255s. This is an obvious omission from the 245. There’s also now a gyroscope.

Of course, the sensors have been upgraded. So you get the latest generation heart rate sensor (Gen 4 ELEVATE) on the 255 and 255s which is capable of more accurate measurements and spitting out raw HRV data.

Sattelite connectivity still has the capability to connect to GPS, GLONASS and GALILEO. But 255 and 255s have multi-frequency reception of global satellite systems. Which should ensure better accuracy even in narrow mountain valleys, urban canyons and other challenging conditions.

Battery life is another area of significant approvement. Both the 255 and 255s have nearly twice the battery of the 245 in smartwatch mode (14 days and 12 days). In other modes the gains are more modest. With GPS on, you can expect up to 30 hours on the 255 and with GPS and music about 6.5 hours.

Here’s a table illustrating all the important hardware details.

The Garmin 245 is a very popular runners watch. It might lack the multitude of sports modes of the higher end Forerunners, Fenix and Epix – but it still comes with everything you need to track your health, fitness and running adventures in great detail.

It has been about three years between these two versions of the watch. So it should come as no surprise that the 255 comes with some handy upgrades over the 245. In addition to the latest generation sensors and support for twice as many sports modes (including triathlon), it has with the following.

The Morning Report was first introduced with the Garmin Lily. But while that is one quite limited in what it can do, the one on Forerunner 255 spits out some more useful information. This includes sleep, recovery time, training status and HRV status immediately after waking up. It also provides you with your daily training recommendation. This can be customized according to one’s needs.

The HRV Status (HRV stands for heart rate variability) is a new metric that is being made available for the first time on the Forerunner 255 and 955. It has been a long time coming and something that Garmin should have included years ago. Presumably the latest generation heart rate sensor is finally accurate enough to be able to churn out this type of HRV data.

The metric is recorded while you sleep. In the morning you are able to see a screen showing your nightly average HRV, along with a 7 day average value. This is all compared against your baseline value captured over a longer period. The goal is to stay in the Green zone and avoid the Red zone.

The Race Widget is also something new. This is a view that can be accessed from your watch. What you’ll find there are race-related training tips, daily suggested workouts, weather forecast, along the estimated finish times based on the course and your training and fitness.

In combination with physiological measurements such as extended training status, acute stress, training effect and more, this should help you exercise well. It enables you to better analyze your training and make it more efficient.

The Forerunner 255 comes with a pre-installed widget for Running Power. This enables you to determine your running performance and other running efficiency values directly and in real time on the watch. Think of it as an alternative to using your heart rate when gauging your effort. Running Power takes into account all sorts of factors, such as elevation, to show how much energy you are using in real-time.

Unfortunately this is not the standalone solution many had hoped for. Instead, it needs a compatible accessory in order to work. This could be either a compatible chest strap or the Running Dynamics Pod. Think of it as an early step to full integration of Running Power in Garmin Forerunner watches.

When you exercise outdoors, the value of the altitude is usually not a very important information. Apart from the absolute altitude difference at beginning and end. What matters more are the multiple elevation gains or losses while you run or cycle up or down a track.

A barometric altimeter is much more precise for this type of information than GPS. This is why barometric altimeters are often used in sports watches. Presumably, the addition of Running Power on the 255 requires a barometric altimeter in order to function well.

Garmin is always looking to improve accuracy. As mentioned above, you can still tap into the three same sattelite systems – GPS, GLONASS and GALILEO. But with the 255 and 255s you have “Multi-Band” or Dual-frequency GNSS (Global Navigation Satellite System) capability. This is useful in challenging environments as it allows the device to detect (and reject) reflected satellite signals better than a single frequency receiver.

The Forerunner 955 also comes with this. This is in addition to Epix (Gen 2) Sapphire and Fenix 7 Sapphire Solar series. Garmin says dual-frequency systems can achieve accuracy within about +/- 2 meters or 6 feet under ideal conditions. Other watches have location accuracy of other models is within about +/- 3 meters or 10 feet under ideal conditions.

Probably not something to write home about, but the 255 and 255 come with an NFC chip. This allows you to use Garmin Pay for contactless purchasess. Useful if you don’t want to bring your wallet during a run. This feature is missing on the Forerunner 245 but is available on many other Garmin watches.

Here’s a recap of the main differences between the three when it comes to activity, sports tracking functionality and smart features between the Forerunner 255 and 245.

The Forerunner 255 is a great choice for someone who primarily runs. It comes with a few worthy upgrades over its predecessor.

The most obvious one is a choice in sizes. You can pick from a large and a small, from a music and non-music – so something for everyone there.

Other improvements come in the form of the latest generation heart rate sensor, a barometric altimeter, multi-frequncy GPS, HRV Status, Running Power, Morning Report, Race Widget, many more sports profiles and support for Garmin Pay. Quite a long list there. And let’s not forget the battery life – it has doubled.

Unless you are on a budget, the choice is obvious – go for the Forerunner 255. There’s only a $50 difference in price. The jump in specs might even prompt some owners of the 245 to sell their device to purchase the newer watch. Of course, the 245 will see an inevitable fall in price, so if you’re after a great deal you will surely be able to find one.

Check Garmin Forerunner 255 availability & price on Amazon | Garmin. Check Garmin Forerunner 245 availability & price on Amazon | Garmin. In certain countries, such as the UK, you can get 15% off on the Forerunner 255 by generating a coupon. Use the coupon on the sportsshoes website.

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I often exercise with an external heart rate monitor paired to my sports watch. As good as wrist based heart

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