Garmin Forerunner 245 vs Forerunner 255 — which should you buy?

So you’re looking for a new running watch, and don’t know whether to add the Garmin Forerunner 245, or the newly released Forerunner 255 to your shopping cart. The Forerunner 255 is the updated version of the Forerunner 245, released in June 2022. Both watches are positioned as midrange running watches in the Garmin range, but which is the best Garmin watch, and which should you invest in? 

Below, we put the Forerunner 245 and the Forerunner 255 face-to-face to help you work out which is best for you and your training. If you’re a complete beginner looking for a more basic running watch, check out the Garmin Forerunner 55, which is the best entry-level running watch on our list. 

Garmin Forerunner 245 vs Forerunner 255: Price and availability

The Garmin Forerunner 255 comes in two different sizes — a 42mm (the Forerunner 255S) and a 46mm; both cost the same. The Forerunner 255 also comes with the option to store music, or not. The Forerunner 255 without music costs $349/£299, and the Forerunner 255 Music costs $399/£349. 

This is slightly more expensive than the Forerunner 245, which hit the market at $299 without music, and $349 with music. Yet following the launch of the Forerunner 255, the Forerunner 245 is likely to be in the sale, so if you are on a budget, now is a good time to invest in the cheaper watch. It's also worth looking at our Garmin coupon codes to see if you can save a little extra.

a photo of the Garmin Forerunner 245

(Image credit: Future/Tom's Guide)

Both watches are still readily available, however as Garmin will have stopped making the Forerunner 245, it won’t be around forever, so if you do have it in your basket, it’s worth checking out soon. 

Winner: Forerunner 245 — as you’ll read below, the Forerunner 255 has a number of features that make up for the $50 difference, but on price alone, the Forerunner 245 is the cheaper option. 

Garmin Forerunner 245 vs Forerunner 255: Specs at a glance 

Swipe to scroll horizontally
Garmin Forerunner 245 vs Forerunner 255
Header Cell - Column 0 Garmin Forerunner 245 Garmin Forerunner 255
Case sizes42 mm 42 mm and 46 mm
Display size30.4 mm27.3 mm / 33 mm
Battery life (smartwatch mode)7 days12 days (Forerunner 255S) / 14 days (Forerunner 255)
Battery life (GPS mode)24 hours without music/ 6 hours with music30 hours without music / 6.5 hours with music (Forerunner 255) or 26 hours without music / 5.5 hours with music (Forerunner 255S)
Built-in GPSYesYes
Heart rate Yes Yes
Garmin PayNoYes
Pulse OxYesYes
MusicYes (on Forerunner 245 Music)Yes (on Forerunner 255/255S Music)
Advanced performance metricsYesYes
Triathlon/mulitsport modesNoYes

Garmin Forerunner 245 vs Forerunner 255: Design and display 

The design and display on the two watches are very similar — both look almost identical on the wrist unless you opt for the Forerunner 255S, which is a lot smaller and neater. Both are controlled using five buttons — three on the left and two on the right. Neither have the touchscreens of the Fenix 7, Garmin Venu 2 Plus and Forerunner 955, but I’d argue that the lack of a touchscreen isn’t all that much of a loss, as the touchscreen is automatically turned off when you’re actually exercising using the watch. Plus, anyone who has ever tried to swipe with a sweaty finger on a touchscreen will know they’re not often worth the price tag.  

a photo of the Garmin Forerunner 245

(Image credit: Future/Tom's Guide)

Both the Forerunner 255S and the Forerunner 255 have a color MIP display that we found easy to read in all conditions, even in direct sunlight. The larger of the two watches also has a higher resolution than the Forerunner 245 — the Forerunner 255 has a 260 x 260 resolution compared to the Forerunner 245’s 240 x 240 pixel resolution. It’s not a difference you’d really notice unless staring at the two watches side-by-side, but the screen on the newer watch definitely looks a little brighter and more colorful. 

Garmin Forerunner 245 vs Garmin Forerunner 255

(Image credit: Future/Jane McGuire)

When it comes to customizing the display on the newer watch, however, things are slightly easier, as like with other newer Garmin watches, it can now all be done from the Garmin Connect app, as well as from the wrist. It’s not all that big a deal, but it does make things a lot easier. 

Verdict: Forerunner 255 — design-wise, the option to have a smaller watch on your wrist is a huge plus, especially for more petite runners. Display-wise, things are ever-so-slightly better on the newer watch. 

Garmin Forerunner 245 vs Forerunner 255: Battery life 

When comparing the battery life on the Forerunner 245 and the Forerunner 255, it’s easiest to think of the watches as three different models. The Forerunner 245 has a very similar battery life to the Forerunner 255S — 24 hours without music and six hours with music, and 26 hours without music and 5.5 hours with music respectively. In smartwatch mode, the Forerunner 245 will last 7 days, whereas the Forerunner 255 will last 12 days. 

average pace chart on the Garmin Forerunner 255

(Image credit: Future/Jane McGuire)

The Forerunner 255 will last 30 hours without music, and 6.5 hours with music. In smartwatch mode, it will last 14 days. 

Verdict: Forerunner 255 — sure, it’s not that dramatic a difference, but the battery life is definitely better on the newer watch. That said, if you do opt for the Forerunner 245, you’ll still be able to run without having to charge your watch for about a week (a huge improvement on the likes of the Apple Watch Series 7). 

Garmin Forerunner 245 vs Forerunner 255: Fitness and tracking features 

When it comes to the fitness tracking features, both watches will track everything you’d expect — indoor and outdoor runs, indoor and outdoor bike rides, swimming, cardio, elliptical sessions, and yoga. They’ll both also track your daily steps, heart rate, stress, sleep, and menstrual tracking. They also both use the same Garmin Connect app, which is a valuable tool and helps make it easy to see all of your health data in simple graphs and graphics. 

Both watches are able to tell you things like your VO2 max, your recommended recovery time after a run, and your body battery — a useful tool that looks at your activity levels, heart rate variability, and stress levels to help you see at a glance how prepared you are for a difficult workout. Both also have the PacePro feature, which stops you from starting a race too fast, and suggested workouts, as well as the LiveTrack and Incident Detection safety features. 

a photo of the heart rate chart on Garmin Forerunner 255

(Image credit: Future/Jane McGuire)

That said, the Forerunner 255 has some key upgrades — the watch has Garmin’s latest Elevate V4 sensor — the green light records heart rate, the red light records blood oxygen levels (referred to as Pulse Ox on the watch). This sensor is used to calculate breathing rate, HRV, and stress. It also has the Morning Report feature, which gives you a snapshot into how well you slept, how hard you’ve been training, and a look at the weather for the day ahead. 

Garmin Forerunner 245

(Image credit: Garmin)

Finally, the most significant difference when it comes to fitness tracking is the fact that the Forerunner 255 has the ability to track multisport activity profiles and triathlon. Until now, the ability to track brick sessions and triathlons has been reserved for more expensive watches in the Forerunner range. Garmin has also added the ‘Up Ahead’ feature (which allows you to see predefined markers such as aide stations and climbs in a race) and the race day specific performance prediction (which allows you to see if you’re getting faster or slower during a race) to the Forerunner 255.

Verdict: Garmin Forerunner 255 — The addition of multisport activity tracking on the mid-level watch is huge. Even if you think you’ll never use it, the fact you have the option to train for a multisport challenge is great.

Garmin Forerunner 245 vs Forerunner 255: Smartwatch features 

Smartwatch-wise, the two watches have pretty much the same features. Both are designed to be worn 24/7 and allow you to see smartphone notifications from your phone on the watch on the move, see weather updates, calendar reminders, and things like find my phone and find my watch. The music versions of both the Forerunner 245 and Forerunner 255 give you the ability to download up to 500 songs and playlists from Spotify or Deezer to the watch and leave your phone at home.

a photo of the Garmin Forerunner 255 home screen

(Image credit: Future/Jane McGuire)

The main difference from a smartwatch perspective is that the Forerunner 255 has the addition of Garmin Pay contactless payments, which allow you to keep your phone in your pocket when commuting. 

Verdict: Garmin Forerunner 255 — The addition of Garmin Pay is useful.  

Garmin Forerunner 245 vs Forerunner 255: Which should you buy? 

While both the Forerunner 245 and the Forerunner 255 are fantastic running watches, if you’re looking to upgrade your running watch, the Forerunner 255 is the better watch to have on your wrist. The Forerunner 255 is superior from a fitness tracking standpoint, with the option to track multisport profiles from your wrist, it’s also got a better battery life, and better trackers. 

That said, if you’re on a budget, or you’re convinced you’ll absolutely never do a duathlon or triathlon, you’re still getting a brilliant watch with the Forerunner 245, and it’s very likely to be on sale right now. At the time of writing, it’s only $20 or so more than the Forerunner 55 — here’s the Forerunner 55 vs the Forerunner 245 if you’re trying to decide between the two. 

Jane McGuire
Fitness editor

Jane McGuire is Tom's Guide's Fitness editor, which means she looks after everything fitness related - from running gear to yoga mats. An avid runner, Jane has tested and reviewed fitness products for the past five years, so knows what to look for when finding a good running watch or a pair of shorts with pockets big enough for your smartphone. When she's not pounding the pavements, you'll find Jane striding round the Surrey Hills, taking far too many photos of her puppy.