Two compact Race watches, one character apart. Suunto Race S arrived in 2024 as the smaller, lighter way into the Race family. Suunto Race 3S is its successor: a new-generation performance watch built for smarter training and trail running, in a case sized for smaller wrists.

Race 3S is the more capable watch. The real question is whether its upgrades change how you train, or whether Race S already covers everything you need.

Here is what changed, what carries over, and how to pick the right compact Race for your wrist.

At a Glance

The Short Answer: Which One Fits You?

Choose Suunto Race S if you:

• want the lighter, more affordable way into a compact Race watch
• run and train at distances that finish well inside 30 hours of GPS
• train mostly in everyday light, where a 600-nit screen reads clearly
• already own Race S and it covers everything you do

Choose Suunto Race 3S if you:

• want a 2,000-nit screen you can read at a glance in full sun, snow glare, or high-altitude light
• go long: big trail days, ultras, or back-to-back sessions between charges
• want Suunto AI Coach building and adapting your training plan
• want sapphire glass, the faster Apollo 510 processor, and an upgraded heart rate sensor
• want 64 GB of storage for maps, routes, and training data

Still weighing it up? The sections below take each difference in turn. And the features you rely on most, free offline maps and dual-band GPS, come with both watches.

Suunto Race 3S vs Race S: Full Comparison

Both watches share their software, their maps, and their core running tools. The gap opens up in six places: display, battery, build, processor, heart rate, and AI Coach.

Display: 2,000 Nits vs 600 Nits

This is the upgrade you notice first, and the one that matters most when the light turns harsh. Both watches use a crisp 1.32-inch AMOLED panel at 466 x 466, so text and maps look sharp on either wrist.

The difference is brightness. Race 3S delivers 2,000 nits, more than three times the 600 nits of Race S. On an exposed ridge at midday, across a snowfield, or under a hard noon sun, that is the gap between squinting at your pace and reading it mid-stride.

Race S stays clear in everyday conditions. Race 3S stays readable in the harshest light you train in.

Battery: Up to 38 Hours of Dual-Band GPS

For long-distance athletes, this can settle it. In its most accurate dual-band GPS mode, Race 3S runs for up to 38 hours, against up to 30 hours on Race S. That is 8 more hours of full-accuracy tracking, right where you need them: deep into a long mountain day.

In daily use, Race 3S lasts up to 12 days between charges, against up to 9 on Race S. Both watches offer further battery modes for longer, lower-power tracking.

The short version: if your longest efforts finish comfortably inside 30 hours, Race S has you covered. If you are training for ultras, stacking back-to-back big days, or simply want to charge less often, Race 3S gives you the headroom.

Build: Sapphire Glass and a Titanium Case

Both watches are built to train and race in any weather, with 5 ATM water resistance for swims, rain, and river crossings.

Race 3S steps up the materials. Its titanium case is topped with sapphire glass, where Race S uses Corning Gorilla Glass. Sapphire is exceptionally scratch-resistant, so if your watch trades knocks with rock, scree, and trekking poles, the screen stays clear for longer.

Race 3S weighs 56 g with strap, a few grams more than Race S in titanium at 53 g. Both are compact watches that sit comfortably on smaller wrists.

Processor: Apollo 510 vs Apollo 4 Plus

Race 3S runs on the new-generation Apollo 510 processor, a step up from the Apollo 4 Plus inside Race S. You feel it every time you swipe through screens, load a map, or start a workout: the watch responds faster and keeps pace while you move.

It is not the spec you will talk about. It is the one you will appreciate in every session.

Heart Rate: An Upgraded Optical Sensor

Race 3S carries an upgraded optical heart rate sensor with six LEDs and four photodiodes, against four LEDs and two photodiodes on Race S. More sensors mean a stronger signal, and that pays off exactly when wrist heart rate is hardest to read: intervals, tempo efforts, and the closing kilometres of a long run. Both watches also pair with a heart rate belt for chest-strap precision.

If wrist heart rate has let you down on hard sessions, this is a strong point in favour of Race 3S.

AI Coach: A Coach That Knows You

The most valuable upgrade on Race 3S is software. Race 3S debuts Suunto AI Coach, Suunto's new-generation coaching experience in the Suunto app.

It builds a personalised training plan around your goals, adapts it as your fitness and recovery change, and answers your training questions in plain language. Pair Race 3S with a heart rate belt and ZoneSense reads your true intensity, so your easy days stay easy and your hard days count.

Every Race 3S bought before the end of 2026 includes three months of Suunto AI Coach.

What Both Watches Share

Whichever you choose, you get the full Suunto Race experience. Both watches include:

• Free worldwide offline maps for confident navigation off-grid
• Dual-band GPS for accurate tracking in cities, forests, and mountains
• Climb Guidance and turn-by-turn navigation
• 5 ATM water resistance
• A full range of sport modes covering running, trail, cycling, swimming, and more
• Race tools including race pacing and finish-time estimates
• Around-the-clock heart rate, sleep, HRV, and recovery tracking
• Complete training analysis, free in the Suunto app

Same maps, same metrics, same analysis. The choice comes down to hardware and the newest coaching.

The Race Takeaway

Race 3S and Race S share the same software, the same free offline maps, and the same compact fit. What sets Race 3S apart is everything new: a 2,000-nit screen you can read in any light, up to 38 hours of dual-band GPS, sapphire glass, the Apollo 510 processor, an upgraded heart rate sensor, and Suunto AI Coach. If those upgrades match how you train, Race 3S is the clear pick. If not, Race S still delivers the core Race experience at a lighter weight and a lower price. Either way, you are wearing a real Race watch.

Explore Suunto Race 3S, the new-generation compact watch from Suunto.

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