Garmin Forerunner 245 vs. 255: Should You Upgrade?

The Forerunner 200 series is one of Garmin’s most popular lines of GPS watches, and while I don’t have industry sales data, I’m willing to bet they’re the most popular GPS watch models across the board.

The Forerunner 255 was released in June 2022 as the successor to the Forerunner 245 that was released in April 2019. The Forerunner 255 is a seriously impressive upgrade, and I’m a big fan despite having switched from Garmin to COROS in 2021.

In this post, I’ll go over the similarities and differences between the two models so you can decide which one is best for you. I was able to use a Forerunner 245 loaner for about a month and used a Forerunner 255S Music for three months before purchasing a lightly used one for further testing.

As context, I’m a distance runner who mostly trains for half and full marathons, but I’ve also dabbled in triathlons and trail running. I’m a GPS watch nerd and have tested 10+ Garmins and all the COROS watches, mostly via loaners or borrowing from friends. I started writing these reviews since I remember how hard it was to pick my first GPS watch, and I want to help you make a decision (check out the rest of my GPS watch comparisons).

This post contains affiliate links , meaning that I earn a small commission on any purchases through those links, at no extra cost to you. Your support allows me to keep writing reviews like this one 🙂

Things in Common: Forerunner 245 and 255

The Forerunner 245 and 255 have a lot of similar features. Here’s a quick refresher of what they have in common.

Fitness tracking for common activities: You’ll be able to track a wide variety of indoor and outdoor activities, including:

Running	Pool Swimming
Indoor + Outdoor Track Running	Strength
Treadmill Running	Cardio and Elliptical Training
Trail Running	Stair Stepping
Virtual Running	Indoor Rowing
Biking	Yoga
Indoor Biking

Everyday fitness stats: steps, floors climbed, heart rate, Pulse Ox, stress, sleep, menstrual tracking.

Training metrics: VO2 max, Recovery Time, Race Predictor, Training Status, Training Load, Training Effect, Body Battery (energy levels based on heart rate variability, stress, and activity).

Workout features: interval workouts, PacePro (helps you create and stick to a pacing plan), suggested workouts, Garmin Coach, breadcrumb navigation, and Audio Prompts.

Smartwatch features: weather, calendar, messages, find my phone, find my watch, Smart Lock (automatically unlock your phone when watch is in range).

Music functionality: download tracks to your watch or use Spotify Premium, Amazon Music, Deezer, or iHeartRadio. Available on the music version only.

Safety features: LiveTrack and Incident Detection, allowing loved ones to track you during your workouts and be alerted if an incident is detected (your watch must be connected to your phone to access these features)

While the watches have a lot in common, the Forerunner 255 offers even more as a newer watch. Let’s get into the differences between the two!

What’s New on the Forerunner 255

The Forerunner 255 is a major update to the Forerunner 200 series. Garmin has been introducing its more premium features to its entry-level and mid-tier watches. The Forerunner 55 is basically a “lite” version of the Forerunner 245, and the Forerunner 255 is essentially an improved Forerunner 745, which is part of Garmin’s triathlon watch series.

The first thing to know is that the Forerunner 255 comes in two sizes: the Forerunner 255S (pictured in this post) and the Forerunner 255. The FR255S was made for people with smaller wrists, so it has a thinner, shorter strap and weighs about 20% less than the FR255 (though it’s actually half a gram heavier than then FR245—that’s a 1% difference).

Keep in mind that while the FR255S weighs almost the same as the FR245, it actually has a slightly smaller screen size and resolution. Here’s how the three watches compare:

	Screen size	Resolution	Weight
FR255	1.3″	260 x 260	49g
FR255S	1.1″	218 x 218	39g
FR245	1.2″	240 x 240	38.5g

The band sizes are also different, with the FR255S having an 18mm band, the FR255 having a 22mm one, and the FR245 having a 20mm one.

So, if you’re looking for more size options, you may like the FR255. As someone with small wrists, I appreciate the thinner strap of the FR255S. It feels more comfortable to wear than the FR245.

One of the biggest upgrades to the Forerunner 255 are the All-Systems and Multi-band tracking modes. “All-Systems” lets the Forerunner 255 use any of the satellite systems (GPS, GLONASS, Galileo, BeiDou, QZSS) and switch between them based on the quality of their signals. This is the default setting for the watch. “Multi-Band” is the dual-frequency option that allows your watch to get L1 and L5 frequency signals, improving tracking accuracy.

The Forerunner 245 doesn’t have All-Systems or Multi-Band, but it does have access to GPS, GLONASS, and Galileo (you can use a combination of GPS plus one or the other). The FR245 is still accurate, so these additional tracking options may only make a big difference if you’re training a lot in cities with skyscrapers or remote areas with poor signal.

I will say though that the FR255S I’ve been testing has the most accurate tracking I’ve seen so far in a watch (in just All-Systems mode too, not even Multi-Band). When I look at the maps of my runs in the app, the route most closely follows the trail of where I actually ran compared to other units.

Another big perk is the improved battery life, which is twice as good in smartwatch mode on the Forerunner 255.

	FR255S	FR255
Smartwatch mode	Up to 14 days	Up to 12 days
GPS-Only GNSS mode	Up to 30 hours	Up to 26 hours
All-Systems GNSS mode with music	Up to 6.5 hours	Up to 6.5 hours
All-Systems GNSS mode	Up to 25 hours	Up to 20 hours
All-Systems GNSS mode plus Multi-Band	Up to 16 hours	Up to 13 hours

In comparison, the Forerunner 245 gets up to 24 hours in GPS mode, 6 hours in GPS mode with music, and 7 days in smartwatch mode.

One other major addition is the ability to track open water swimming and triathlon/multisport. This is what originally set the Forerunner 700 series apart from the 200 series. Now that the Forerunner 255 has open water swimming, we may never see a Forerunner 755.

Beyond that, there are these additional tracking profiles in the Forerunner 255: Ultra Running (lets you track your rest time), Mountain Biking, Floor Climbing, Pilates, Hiking, Skiing, Snowboarding, XC Classic Skiing, Stand Up Paddleboarding, and Rowing (outdoor).

The Forerunner 255 also has a barometric altimeter, while the Forerunner 245 had to use a GPS altimeter to estimate elevation stats. The barometric altimeter allows you to get real-time elevation readings and more accurate elevation stats in general. If you’re mainly a road runner though, you can always correct your elevation data after the fact in Strava.

For more in-depth recovery and training performance data, the Forerunner 255 measures heart rate variability (HRV) while you sleep. When you maintain a good balance between training and recovery, your HRV will be balanced. HRV is considered in the Training Status metric, which lets you know if you’re training too much, too little, or just enough.

A lifestyle upgrade is the addition of Garmin Pay, which allows you to make contactless payments with your watch. Most major banks and cards are compatible.

If racing is a big part of your exercise routine, you’ll like the new race widget, which offers you training tips, personalized daily suggested workouts, and finish time predictions based on the course, weather, and your training.

While the Forerunner 245 also has Race Predictor, you’ll be able to see how your predicted finish times have trended over time on the Forerunner 255.

To help you measure your running intensity, the Forerunner 255 also has wrist-based running power. Running power takes into account your pace, vertical oscillation, grade, and wind conditions to calculate the amount of power you’re applying to the ground as you run. This metric can help you better pace yourself.

Finally, the Forerunner 255 has a morning report, which summarizes your sleep, recovery, training, and HRV status when wake up. You can customize the report to add or subtract other features like Body Battery, weather, menstrual cycle, and more.

Should You Upgrade from the Forerunner 245?

Given the addition of open water swimming/triathlon, Garmin Pay, and improved tracking modes, the Forerunner 255 feels like an entirely different watch from the Forerunner 245. I’d say it’s one of the best-value out there right now, if not the best.

In fact, I liked the Forerunner 255S Music so much that I purchased a lightly used one on eBay for further testing after using a loaner for 3 months. I switched to COROS after my Garmin Vivoactive 3 Music died in April 2021 and figured I should own at least one functional Garmin and COROS as a GPS watch reviewer (I haven’t yet had a chance to compare the latest pool swim tracking and open water swim tracking).

If your Forerunner 245 isn’t doing everything you want it to, then it could be worth upgrading. But if it still does what you want, then stick with it (better for your wallet and the planet).

Is the Older Forerunner 245 Still Worth Buying?

The Forerunner 245 is still a really capable watch. It has Garmin’s more advanced training metrics, decent battery life, pool swimming, trail running, and safety features.

While I wouldn’t buy it at full retail price today, if you can find it for under $250 new or used, it’s great value. I’ve even seen it go for under $200 on secondhand platforms. As you’re getting closer to the $300 range for the Forerunner 245, it just feels too close to the price of the FR255, which has so many more features.

Of course, it ultimately comes down to what you need. If you won’t use the extra features, then it’s not worth the extra money, even if it’s a small amount. Just be honest with yourself about whether you might get FOMO if you go with the FR245 because upgrading later on will cost you more money in the long run.

Where to Buy the Forerunner 245 and 255

If this review helped you, it would mean a ton if you purchased through my affiliate links or codes. I also want to encourage you to buy secondhand or from small, local running stores if you can. I don’t get paid if you do that, so if you still want to show your appreciation financially, you’re welcome to buy me a virtual coffee.

Garmin

Forerunner 245
Forerunner 255

Amazon

Forerunner 245
Forerunner 255

Other retailers

Swappa (used electronics)
Mercari (used marketplace)
REI
eBay

If you have any questions, feel free to leave them in the comments. Also let us know what you decided on and why!

You may also like these posts:

Forerunner 255 vs. 745
Forerunner 55 vs. 255
Forerunner 55 vs. 245
Forerunner 255 vs. COROS APEX 2
Forerunner 255 vs. COROS PACE 2