Garmin Forerunner 255S Music

Garmin Forerunner 255S Music is the ultimate compact triathlon watch

Garmin Forerunner 255S Music
Garmin Forerunner 255S Music review
(Image: © Future)

TechRadar Verdict

The Garmin Forerunner 255S Music packs in full triathlon tracking with a new heart rate monitor, the latest multi-band GNSS tracking plus onboard music support for offline Spotify. All of that is in one of the smallest watches out there making it comfortable for day and night wear. You won't get solar charging but for the price we wouldn't expect that.


  • +

    Full triathlon support

  • +

    Onboard music

  • +

    HRV tracked

  • +

    New heart rate and multi-band GNSS


  • -

    No real-time stamina

  • -

    No solar charging

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Two minute review

This is our full review of the Garmin Forerunner 255S Music. We’ve reviewed the top-end Garmin Forerunner 955 Solar already and were impressed, but can Garmin do the same at this lower price point? The short answer is yes. 

As the follow-up to the popular Garmin Forerunner 245, this 255S Music model takes that to a new level with triathlon support, onboard music storage and more. In fact this is a contender for best running watch outright, not just best Garmin watch.

One feature that jumps out is the size of this watch which is so compact you can truly train – and sleep track – without noticing you're wearing the watch. It does that while not scrimping on features or long-life battery performance with up to 30 hours of GPS tracking and over a week on standby.

The addition of Garmin's multi-band GPS abilities makes this a super accurate tracking device. Combined with the newly upgraded heart rate monitor you also have a wealth of helpful metrics to show how you're training. Training Readiness and Body Battery help tell you when you're ready to train again, so as to keep you progressing without pushing yourself too far at any point.

This supports recovery effectively, essential for everyone from casual park-runners to high-performance triathletes and ultra-runners. This is all supported by a battery that lasts well and loads of storage space for all your favorite music and routes.

For a near-do-it-all smartwatch that keeps the price low, this is a really attractive option.

Garmin Forerunner 255S Music: Price and availability

The Garmin Forerunner 255S Music is out now in the US, UK and Australia. The suggested retail price sits at $440/£350/AU$699. 

There is also the basic Forerunner 255 model which doesn't have that onboard music capability which can save you money priced at $375/£300/AU$629.

There are currently some Garmin promo codes that could help you save when you buy.

Garmin Forerunner 255S Music

(Image credit: Future)

 Garmin Forerunner 255S Music: Design 

Garmin Forerunner 255S Music: Design

  • Compact and comfortable to wear
  • Display is clear, but not battery-draining
  • This is the smaller 41mm size

The watch is compact and comfortable with a face that's suitable for most wrists and that super adjustable and comfy silicone strap. It's worth noting that the 255S Music comes in the smaller 41mm size while the 255 has a larger 46mm size, despite not offering the music feature.

Whichever option you go for, it's going to be underwater ready with 5ATM water resistance, making it fine for tracking swimming both for indoors and open water.

The display is built for use even in bright sunlight thanks to transflexive memory-in-pixel display which saves battery while being super clear. Resolution on the 255S' 1.1-inch display is decent at 218 x 218 pixels (1.3-inch and 260 x 260 on the 255) and the color helps with the clarity here. At under 49g on both models you barely notice you're wearing this watch.

Garmin Forerunner 255S Music

(Image credit: Future)

What you don't get is a touchscreen, but thanks to intuitive menus it works well with button presses – and also means you don't need to worry about accidental pressing, screens smudges, or issues controlling it in the water. The ability to personalize your screen layout is also helpful so you have quick access to what you use the most. Plus, having five buttons at your disposal makes jumping to what you need, quickly, as easy as it can be.

  • Design score: 4.5/5

Garmin Forerunner 255S Music

(Image credit: Future)

Garmin Forerunner 255S Music: Features

  • New triathlon tracking support
  • Heart rate variability is a big step up
  • Train and rest based on recovery rate

The Garmin Forerunner 255 comes as an upgrade to the 245, so what's new that makes this worth the extra expense? First and foremost it's the new triathlon tracking support, meaning you can now track swimming, cycling and running as one event, using lap timer taps to track your transition times too.

The upgraded heart rate monitor here means you can now track Heart Rate Variability (HRV) which is a hugely important metric for true analysis of how your body is fairing. It's the difference in the heart beats, showing rhythm where in this case the higher the number, the better you're doing. As such you can see if it's right for you to train or not based on your workouts up to that point.

Garmin Forerunner 255S Music

(Image credit: Future)

The Race Widget is a useful addition which lets you prep for a race day with a countdown clock, performance predictor and race day weather – all of which helps make suggestions for your workouts in the lead up.

The Morning Report is a great feature which will let you know about your sleep, the weather and your daily workout suggestion – like a personal trainer but with even more accurate data making it perfectly suited to you.

Garmin Forerunner 255S Music

(Image credit: Future)

There is a Native Running Power feature, which gives you real-time power output metrics as you run. The downside here is that you need an external sensor, like the Garmin HRM-Pro to take advantage of this feature.

The sleep score and body battery numbers are helpful as part of the suggested workouts feature, which did get me training when I may have otherwise rested – and vice versa, resting when I may have trained. That said, when you've had a bad night's sleep and this is telling you that, it really can feel less than helpful – dare I say annoying to have that shoved in your already bleary eyes at the start of the day.

All that said, it can be nice to wake up and be told that you need to have a rest day. I did find this a good "out" but equally found being told I should train felt a bit forced. So if you want a coach it's ideal, but if you like to feel free then it may be seen as constrictive. 

Garmin Forerunner 255S Music

(Image credit: Future)

While the list of metrics measured goes on and on some key points include 24/7 heart rate tracking, sleep tracking, stress tracking, VO2 max estimations, training status reports, smart notifications, weather reports, many many sports modes, step counter, blood oxygen measurements, Body Battery, and on and on. This is thanks to the IQ Store access which means you can add pretty much anything other Garmin watches can track if the mode is available to add.

  • Features score: 4.5/5

Garmin Forerunner 255S Music

(Image credit: Future)

Garmin Forerunner 255S Music: Performance

  • Amazing current-gen fitness tracking
  • Pinpoint accurate GPS
  • Good battery life

Garmin tracking is more accurate than ever right now and the 255S shows that with ease. Sure, wrist-based heart rate tracking is still not perfect but it's now at a level where you don't get that much more from wearing a dedicated chest strap. As such this was able to offer useful performance data live as well as post-training for analysis – which the Connect app helps visualize nicely. 

Garmin Forerunner 255S Music

(Image credit: Future)

GPS tracking is also pinpoint accurate now thanks to the addition of the GNSS support, although this does mean you're going to chew into the battery life faster. With up to 12 days on standby and 30 hours of GPS tracking (20 hours with GNSS) you rarely need to think about charging and it'll even manage to track your entire Iron Man tri if that's what you need. Sure it's not at the Garmin Enduro level, which has a mind-boggling time of 60 days. But at the size and with regular training I didn't charge it more than once a week.

Getting out running, cycling and swimming the tracking for heart rate was accurate but it's worth noting that the watch will use algorithms to smooth out the results. As such if you're doing HIIT type training there is less accuracy in the moment, or so it feels, with heart rate on the watch lagging a little behind a training machine tracking, for example. The end results in Connect will be accurate and clear, once it's done that algorithm smoothing, but live you may find a chest strap can get you even more clarity.

GPS acquisition was super fast, getting satellites and being ready to go within 10 to 20 seconds every time I stepped outside. Like with the heart rate monitoring I found when compared to the premium Fenix tracking, this did estimate differently in the first mile or two before levelling out. But even this was barely noticeable, just worth noting as for pinpoint accuracy paying more for the premium watches does make a difference – presuming your arm can carry the weight of a Fenix. For the variation in accuracy and the huge size difference I found the Forerunner a better option, especially for longer range triathlon training.

  • Features score: 5/5

Buy it if...

You want precise tracking

It's hard to imagine a watch in its price range that can better the 255s Music in GPS and fitness metric accuracy. If you want the best-in-class tracking, it's here. 

You don't want to take your phone on runs

The 255S Music allows you to load your own music or podcasts onto the watch and listen on the fly. It means no phones are needed in a pocket, arm or chest strap. 

Don't buy it if...

You want big battery life

Heavier-hitters like the Garmin Forerunner 955 Solar or Enduro can last far longer than this pocket rocket. 

You want a stylish lifestyle smartwatch

This is primarily a running tool, not an Apple Watch. Consider the Garmin Venu Sq 2 is you're looking for something more in that style. 

Also consider


Garmin Forerunner 55
An entry level Forerunner model that gets you lots of the smart running features, heart rate and GPS tracking as well as that fantastic Connect app support. The GPS and HR hardware isn't as advanced but you still get swimming tracking and it's less than half the price of the 255S Music.


Garmin Enduro
If you only want to charge your watch a handful of times a year rather than once a month, this is the watch for you. No music capabilities, but the Enduro is fully kitted out for all manner of endurance athletes. 

First reviewed August 2022

Luke Edwards

Luke is a freelance writer and editor with over two decades of experience covering tech, science and health. Among many others he writes across Future titles covering health tech, software and apps, VPNs, TV, audio, smart home, antivirus, broadband, smartphones, cars and plenty more. He also likes to climb mountains, swim outside and contort his body into silly positions while breathing as calmly as possible.