Coros Pace 3 Vs. Garmin Forerunner 255: A Runner’s Real-World Comparison

As a runner who’s spent countless miles testing gear, I’ve strapped on both the Coros Pace 3 and Garmin Forerunner 255 to see how they stack up. My goal? To help you decide which watch best fits your running life, whether you’re chasing a 5K PR or tackling an ultra.

This article breaks down their features, performance, and quirks through my own experience, with a detailed comparison of pros and cons. By the end, you’ll know which watch suits your needs and why.

A Brief Comparison Table

My Journey With These Watches

I’ve been running for over a decade, from city streets to mountain trails, and I’ve learned that a good running watch is like a trusted training partner. It needs to keep up, give reliable data, and not feel like a brick on my wrist.

When I got my hands on the Coros Pace 3 and Garmin Forerunner 255, I was excited to put them through their paces. I wore them on opposite wrists for weeks—yes, I looked like a total gear nerd—to compare everything from GPS accuracy to comfort during sweaty long runs.

Here’s what I found.

Design And Build: Comfort Meets Durability

• Coros Pace 3

The Coros Pace 3 feels like it was made for runners who hate feeling weighed down.

At just 30 grams with the nylon strap, it’s one of the lightest GPS watches I’ve ever worn.

I barely noticed it during a 20-mile trail run, which is saying something when you’re dodging roots and rocks.

The 1.2-inch Always-On Memory LCD touchscreen is crisp enough to read mid-run, even in bright sunlight, and the nylon fiberglass blend case feels tougher than its predecessor, the Pace 2. I’ve accidentally bashed it against a doorframe, and it didn’t show a scratch.

The Pace 3’s control system is simple: two buttons, one being a digital crown that doubles as a scroll wheel. I found it intuitive for navigating menus, though the touchscreen can be a bit finicky when my fingers are sweaty.

The 5 ATM water resistance means it’s fine for swimming or getting caught in a downpour, which I tested during a rainy 10K. My only gripe? The design is sleek but a bit plain—think functional athletic gear, not a fashion statement.

• Garmin Forerunner 255

The Garmin Forerunner 255 comes in two sizes: the 46mm (49 grams) and the 255S (41mm, 39 grams). I tested the smaller 255S, and while it’s heavier than the Pace 3, it still felt comfortable on my wrist during long runs.

The 1.1-inch MIP display (1.3-inch on the larger model) is clear but lacks a touchscreen, relying on five buttons for navigation. At first, I found the buttons a bit “squishy,” as some reviewers noted, requiring a firmer press than I expected.

After a week, I got the hang of it, but I missed the touchscreen for quick menu hops.

The Forerunner 255 uses Corning Gorilla Glass 3 for the lens, which held up well against minor scrapes during trail runs. The silicone strap is soft and stayed secure, even when soaked with sweat or pool water (it’s also 5 ATM rated).

Color options like powder gray and light pink add a bit of flair, but the overall look is still sporty, not something I’d wear to a fancy dinner.

Pros And Cons: Design and Build

Coros Pace 3 Pros:

• Ultra-light at 30 grams, perfect for long runs.
• Durable nylon fiberglass construction.
• Touchscreen adds convenience for casual use.

Coros Pace 3 Cons:

• Plain design might not appeal to style-conscious runners.
• Touchscreen can be less responsive when wet.

Garmin Forerunner 255 Pros:

• Two size options cater to different wrist sizes.
• Gorilla Glass 3 lens resists scratches.
• Comfortable silicone strap for all-day wear.

Garmin Forerunner 255 Cons:

• Heavier than the Pace 3 (39-49 grams).
• No touchscreen; button navigation feels dated.
• Buttons require a learning period for precise presses.

Performance And Accuracy: Tracking Your Runs

• GPS and Heart Rate Accuracy

Both watches boast advanced GPS tech, but they approach it differently.

The Coros Pace 3 uses dual-band GPS and connects to five satellite systems (GPS, GLONASS, Galileo, Beidou, QZSS).

I tested it in dense urban areas and forested trails, and it locked onto satellites faster than the Garmin, often in under 10 seconds.

The distance tracked during a 10K race was spot-on at 10.03 km, compared to a verified course.

However, I noticed slight inaccuracies in track running—my mapped position was sometimes a lane off, though the total distance remained accurate.

The Garmin Forerunner 255 also uses multi-band GPS with SatIQ technology, which switches between GPS modes based on signal strength to save battery. In my tests, it was marginally more accurate in challenging environments like city canyons, with smoother GPS tracks that hugged the actual path.

During the same 10K race, it logged 10.02 km, nearly identical to the Pace 3. Heart rate tracking on both was solid when compared to a Polar H10 chest strap, though the Garmin occasionally outperformed the Coros during high-intensity intervals, with fewer spikes or drops.

• Battery Life

Battery life is where the Coros Pace 3 shines. It claims up to 24 days in smartwatch mode and 38 hours in standard GPS mode (15 hours with dual-band). In my testing, it lasted 20 days with daily runs of about an hour, using standard GPS and occasional HRV tracking.

For an ultra-marathoner, this is a game-changer—no need to charge mid-race.

The Forerunner 255 offers 14 days (46mm) or 12 days (255S) in smartwatch mode and 30 hours (46mm) or 26 hours (255S) in GPS mode. I got about 10 days with similar usage, which is still impressive but doesn’t match the Pace 3.

The SatIQ mode helped stretch battery life slightly during mixed urban and trail runs.

Pros And Cons: Performance And Accuracy

Coros Pace 3 Pros:

• Exceptional battery life (24 days smartwatch, 38 hours GPS).
• Fast satellite acquisition.
• Reliable heart rate and distance tracking.

Coros Pace 3 Cons:

• Slight GPS inaccuracies on tracks.
• Dual-band GPS drains battery faster.

Garmin Forerunner 255 Pros:

• Highly accurate GPS with SatIQ for efficiency.
• Consistent heart rate tracking, especially during intervals.
• Smooth GPS tracks in challenging environments.

Garmin Forerunner 255 Cons:

• Shorter battery life compared to Pace 3.
• Slower satellite lock-on in some scenarios.

Training Features: Tools For Improvement

• Coros Pace 3

The Coros Pace 3 is packed with training tools via its EvoLab platform.

I loved the race predictor, which estimated my marathon time based on recent runs—it was scarily accurate for my last race.

The watch offers metrics like running performance, training load, and fatigue level, which helped me avoid overtraining during a half-marathon buildup.

Its multisport mode is a boon for triathletes, seamlessly transitioning between swim, bike, and run.

You can also build custom routes in the Coros app, which I used for a trail run with breadcrumb navigation. The app’s training plans are fully viewable, unlike Garmin’s, which only show a week at a time.

However, the Pace 3 lacks some of Garmin’s advanced metrics, like Body Battery or stress tracking. I missed these during recovery days when I wanted a holistic view of my readiness.

• Garmin Forerunner 255

The Forerunner 255 is a training powerhouse. Its PacePro feature creates pacing plans based on elevation and goal times, which I found invaluable for a hilly 10K. It also offers Training Status, HRV, and VO2 max estimates, giving a comprehensive picture of fitness and recovery.

During a tempo run, the Training Effect metric showed how my workout impacted aerobic and anaerobic fitness, which helped me tweak my sessions. The Garmin Connect app is polished, with detailed analytics and integration with platforms like Strava.

However, setting up training plans from the phone was more convenient than Coros, but I wished I could preview the full plan.

Pros and Cons: Training Features

Coros Pace 3 Pros:

• EvoLab provides detailed running metrics.
• Multisport mode for triathletes.
• Full training plan visibility in the app.

Coros Pace 3 Cons:

• Lacks lifestyle metrics like stress or Body Battery.
• Fewer activity-specific profiles than Garmin.

Garmin Forerunner 255 Pros:

• PacePro and Training Effect for advanced training.
• Comprehensive health metrics (HRV, VO2 max, stress).
• Robust app ecosystem with third-party integration.

Garmin Forerunner 255 Cons:

• Limited training plan visibility.
• No multisport mode (available on higher-end models).

Smart Features: Beyond the Run

• Coros Pace 3

The Pace 3 keeps smart features minimal but functional. It supports notifications, weather forecasts, and music storage (4GB for MP3s). I found the music feature clunky—you have to drag and drop MP3s via a computer, which feels like a throwback to the early 2000s.

Breadcrumb navigation is handy for trail runs, but it’s basic compared to full maps on pricier watches. The Coros app is straightforward, syncing data quickly over Wi-Fi, but it lacks the depth of Garmin’s ecosystem.

• Garmin Forerunner 255

The Forerunner 255 (Music version) is a smarter watch. It supports Spotify, Deezer, and Amazon Music, letting you sync playlists wirelessly. I loved queuing up a podcast during a long run without needing my phone.

Garmin Pay adds contactless payments, which I used for a post-run coffee.

The Connect IQ store offers watch faces and apps, though I found many watch faces uninspiring. Notifications and calendar syncing are seamless, making it feel more like a smartwatch than the Pace 3.

Pros and Cons: Smart Features

Coros Pace 3 Pros:

• Basic notifications and weather work well.
• Wi-Fi syncing is fast and reliable.
• Music storage included at no extra cost.

Coros Pace 3 Cons:

• Music requires manual MP3 uploads.
• Limited smartwatch features compared to Garmin.

Garmin Forerunner 255 Pros:

• Robust music streaming with Spotify and podcasts.
• Garmin Pay and Connect IQ enhance functionality.
• More lifestyle-oriented features.

Garmin Forerunner 255 Cons:

• Music version costs $50 extra.
• Watch faces lack creativity.

User Experience: Real Runs, Real Insights

Wearing both watches simultaneously gave me a clear sense of their strengths.

On a 15-mile trail run, the Pace 3’s lightweight design and long battery life were unbeatable.

I didn’t worry about it dying, even with dual-band GPS on.

The crown made scrolling through data screens easy, but I wished for more lifestyle metrics to gauge recovery.

The Forerunner 255 excelled in urban settings, where its GPS tracks were spot-on, and the PacePro feature kept me on pace during a half-marathon.

The button-only navigation took some getting used to, but the wealth of training data made it worth it. For social runners, Garmin’s community features, like challenges, added a fun competitive edge.

Price and Value: Bang for Your Buck

At $229, the Coros Pace 3 is a steal for its features. The two-year warranty adds peace of mind, and Coros’s history of software updates means it’ll stay relevant longer.

The Forerunner 255, at $349 ($399 for Music), is pricier but offers more advanced training tools and smart features.

During sales, the price gap narrows (I’ve seen the 255 drop to $249), making it a tougher call. If budget is key, the Pace 3 delivers incredible value. If you want a more complete package, the Garmin justifies its cost.

Which Should You Choose?

After weeks of testing, I lean toward the Coros Pace 3 for its unbeatable battery life, lightweight design, and affordability. It’s perfect for runners focused on performance metrics and long-distance training, especially if you don’t need extensive smart features.

However, the Garmin Forerunner 255 wins for its robust training tools, smarter ecosystem, and versatility across activities. If you value lifestyle features or plan to use advanced metrics like PacePro, the Garmin is worth the extra cash, especially on sale.

Ultimately, your choice depends on your priorities. Are you a minimalist runner who wants a reliable, long-lasting watch? Go Coros. Do you crave data depth and smartwatch perks? Garmin’s your pick. Whichever you choose, both will elevate your training.

Frequently Asked Questions (FAQ)

Conclusion: Your Run, Your Choice

You’re out there pounding the pavement or hitting the trails, and you need a watch that matches your vibe. I’ve run with both the Coros Pace 3 and Garmin Forerunner 255, and they’re both fantastic in their own ways.

The Pace 3 is your lightweight, budget-friendly endurance champ, while the Forerunner 255 is the data nerd’s dream with smartwatch flair. Think about what you value most—battery life or ecosystem, simplicity or features—and pick the one that’ll push you to your next PR.

Happy running!