Garmin has pulled back the curtain on the Forerunner 255 series - the much-rumoured upgrade to the company's mid-range running watch

Unlike the previous generation, the watch will be available in two case sizes this time around, though Garmin will still offer a separate version for offline music playback.

There's the 41mm Forerunner 255S and Forerunner 255S Music, as well as the 46mm Forerunner 255 and Forerunner 255 Music. Aside from the music feature and the case size, the only other real point of difference is the price - the standard models will both be $349.99 / £299.99 / €349.99, while the Music models cost $399.99 / £349.99 / €399.99.

So, what's actually new here? Well, the headline changes aren't as dramatic as the Garmin Forerunner 955 released alongside this series, but there's still plenty to dive into.

Perhaps the most interesting additions are in the software, with plenty of new tools being given to users to help them track their exercise. The 255 series will feature full triathlon support for the first time, with the ability to switch up tracking in races or brick workouts now available at the touch of a button. 

Like the Forerunner 955, there's now also a new race widget. This gives users at-a-glance information regarding race time prediction, weather and a countdown clock, with daily workout suggestions also changing based on how close the user is to a scheduled race.

This is in addition to Morning Report, which starts the user's day with weather information, a workout suggestion, a sleep tracking summary and the all-new HRV Status. This feature tracks heart rate variability during the user's sleep in order to glean more information for recovery insights. 

Away from exercise, support for Garmin Pay has now also finally arrived, while battery life appears to have been greatly improved from the Forerunner 245 series. 

Garmin suggests that 255 models should be able to reach around 14 days of life in smartwatch mode and 30 hours in GPS mode, which would be a big jump from the seven days in smartwatch mode and 24 hours in GPS mode available with the last generation. That GPS mode won't just be better on a battery front, either, with the new multi-band, multi-satellite GPS also likely to improve lock-on times and accuracy.

We're currently testing out the Forerunner 255S, and we'll be posting our full verdict in the coming weeks. 

Garmin Forerunner® 255S Music, Smaller GPS Running Smartwatch with Music, Advanced Insights, Long-Lasting Battery, Black

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