Garmin Swim 2 vs Apple Watch Ultra: Best Swim Watch?

This is the Garmin's home turf — and it shows. The Swim 2 detects stroke style automatically — freestyle, backstroke, breaststroke, butterfly — and switches between them mid-session without you doing anything. Lap counting is accurate. SWOLF score (stroke efficiency metric) is tracked. Rest intervals are detected automatically. Drills mode is available. It's the most complete pool swimming data you can get from a wrist device at any price.

The Apple Watch Ultra tracks pool swimming well — but not at the same depth. Stroke detection exists but is less reliable, particularly for breaststroke and butterfly. Lap counting is accurate for freestyle. For recreational swimmers this is fine. For competitive swimmers or those following structured plans who want stroke-by-stroke data, the Garmin's granularity is noticeably better.

Here the Apple Watch Ultra pulls ahead. Its dual-frequency GPS is more accurate in challenging conditions — near tall buildings, under bridges, overcast skies. It also meets EN 13319 dive computer standards (rated to 100m), which means it handles genuine ocean and lake swimming pressures with no concerns.

The Garmin Swim 2's GPS is adequate for open water distance tracking but not exceptional. For casual open water swimmers, it's fine. For triathletes who want precise swim split data for race analysis, the Ultra's GPS accuracy is a meaningful upgrade.

Both watches use optical wrist-based heart rate sensors — a universal limitation for accuracy during active swimming. In practice, both give you a reasonable sense of effort zones rather than precise beat-by-beat data during active sets. Neither replaces a chest strap if you need accuracy for training zones.

Between the two, Garmin's algorithm for swimming has been refined over more product generations and tends to produce cleaner data. The difference is marginal in real use — don't choose between these watches based on heart rate accuracy alone.

The Garmin wins decisively. Seven days of regular use means you charge it once a week. During a typical swim session this doesn't matter — but in terms of overall ownership experience, not thinking about charging is genuinely valuable.

The Apple Watch Ultra lasts 36 hours in normal use (72 in low-power mode). For a 90-minute pool session, the battery difference is irrelevant. For multi-day open water events, training camps, or Ironman races, battery becomes a real constraint with the Ultra.

The Apple Watch Ultra supports offline music storage — sync Spotify, Apple Music, or other playlists before your session and play directly from the watch. Pair it with waterproof Bluetooth bone conduction headphones for a fully wireless swim music setup.

The Garmin Swim 2 has no music playback. Zero. If listening to music while swimming matters to you, pair it with a dedicated swimming MP3 player like the SONR Music for pool use — which is arguably a better audio experience than any watch-based solution anyway.

The Apple Watch Ultra is a full smartwatch — notifications, calls, payments, apps, Siri, navigation. If you want one device for swimming and the rest of your life, it does that well. The interface is polished and familiar to iPhone users.

The Garmin Swim 2 has basic smartwatch features — notifications, simple apps — but they're not the point. The interface is designed around workouts, not daily life. Most swimmers who own a Garmin Swim 2 also carry a separate phone for everything else. That's intentional.