Suunto Nautic S Review

The Suunto Nautic S is the compact sibling of the larger Nautic, designed for divers and freedivers who want advanced features in a wearable watch-style package. After seeing early units at dive shops and talking with recreational instructors who’ve been testing them, I can say this computer is generating serious interest as a potential Ocean alternative for divers who don’t need sports tracking. The standout features are that bright 1.4-inch AMOLED display in a proper watch format, the impressive 60-hour battery life, and Bühlmann 16 GF algorithm with multi-gas support including trimix. This is Suunto’s play for divers who want a dedicated dive computer that can also function as an everyday watch without all the sports bells and whistles.

What You’re Getting

The Nautic S package includes the computer with an elastic textile strap, USB charging cable, quick start guide, and warranty materials. Pricing sits at $499 USD for the computer alone, or roughly $799 with a Tank POD transmitter bundle. The computer weighs just 74 grams and features a 1.4-inch AMOLED display with 466 x 466 pixel resolution and sapphire crystal glass. It’s rated to 100 meters water resistance with a dive depth rating of 80 meters, which covers all recreational diving and entry-level technical diving. The rechargeable lithium-ion battery delivers up to 60 hours of dive time on a single charge. You get air, nitrox, multi-gas, gauge, and freediving modes with Suunto’s Bühlmann 16 GF algorithm. The computer supports wireless air integration with up to five Tank PODs and includes GPS, offline maps, digital compass, and weather data. The elastic textile strap is designed to fit over exposure suits and uses a quick-release mechanism that’s compatible with standard 22mm Suunto Ocean and outdoor straps.

Real-World Performance

Display and Visibility

The 1.4-inch AMOLED display is genuinely impressive for a watch-sized dive computer. It’s bright, sharp, and readable in all conditions from bright tropical sunlight to murky low-visibility diving. The sapphire crystal is genuinely scratch-resistant, which is a nice upgrade from acrylic glass on cheaper computers. Early testers mention the color display makes information processing much faster than monochrome screens, with depth, no-decompression time, and tank pressure instantly visible at a glance. The display size is larger than the Suunto D5 and comparable to the Ocean, making it feel premium for a watch-style computer. The interface uses three buttons that work well with gloves, though they’re not as oversized as the larger Nautic’s buttons.

Battery Life

The 60-hour dive time on a single charge is excellent for a watch-sized computer. For comparison, that’s double what most similarly-sized dive computers offer. One instructor testing a pre-release unit mentioned doing a full week of liveaboard diving, four dives per day, without needing to charge. For typical recreational divers doing weekend trips, you’re looking at weeks or even months between charges. The rechargeable battery eliminates the hassle of battery replacements, though you do need to remember the charging cable on dive trips. The battery performance puts it ahead of the Shearwater Tern TX and competitive with larger computers like the Perdix.

Bühlmann 16 GF Algorithm

The Nautic S runs Bühlmann 16 GF, which is a significant departure from Suunto’s historical reliance on proprietary RGBM algorithms. This puts it in line with Shearwater, Garmin, and other technical diving computers. You get customizable gradient factors with preset options of 30/70 (conservative), 40/85 (medium), or 45/95 (less conservative), plus the ability to dial in custom values. The computer displays GF99 and surface GF in real-time, which technical divers appreciate for managing ascent profiles. For recreational divers coming from older Suunto computers with RGBM, this means noticeably longer bottom times, especially on repetitive dives. Several early adopters on ScubaBoard mention the algorithm compatibility makes team diving much easier when buddies are using Shearwaters or other Bühlmann-based computers.

Multi-Gas and Technical Features

The Nautic S supports up to five gases including trimix, which is impressive technical capability in a watch-sized package. You get full decompression planning built into the device. For sidemount divers, it can display pressure from dual Tank PODs simultaneously with switch alerts. The computer handles gas switches during the dive and alerts you when a better gas is available. The dive planner shows expected decompression obligations, ceiling depths, and gas requirements. For a $499 computer, having trimix support with Bühlmann 16 GF and customizable gradient factors is genuinely competitive with computers costing twice as much.

Freediving Mode

The dedicated freediving mode is a nice addition that sets this apart from pure scuba computers. It includes surface interval timing, apnea alarms, and depth tracking. Freedivers who’ve tested it mention the display is easy to read during surface intervals and the watch format is more comfortable than larger wrist-mounted computers. This makes the Nautic S a genuine option for divers who split time between scuba and freediving, similar to the Ocean but without the sports tracking overhead.

GPS and Navigation Tools

The built-in GPS with offline maps is excellent for logging dive sites and tracking surface navigation. You can mark entry points, review your underwater route in the Suunto App, and share dive sites with buddies. The digital compass with tilt compensation works well underwater for basic navigation. The GPS is surface-only like most dive computers, but the ability to track where you’ve been and plan where you’re going adds real value for dive travel. The weather data, tide information, and sunrise/sunset times are helpful for planning dive days, especially in tidal areas or when planning dawn or dusk dives.

Comfort and Wearability

At 74 grams, the Nautic S is light enough for all-day wear as a regular watch. The elastic textile strap is designed to fit over wetsuits and drysuits with a simple pull-and-adjust system. Early feedback suggests the strap is comfortable and versatile, though some divers prefer switching to standard silicone straps for everyday wear using the quick-release mechanism. The watch profile is compact enough that it doesn’t catch on things during gear setup or overhead environments. Compared to the Suunto Ocean which weighs 92 grams, the 18-gram difference is noticeable for smaller wrists.

Stacking Up Against the Competition

At $499, the Nautic S sits in interesting territory. The Suunto Ocean ($900-1,100) offers the same dive features plus comprehensive sports tracking, heart rate monitoring, and smart notifications, but costs nearly double. The Shearwater Tern TX ($550-600) is the closest competitor, offering Bühlmann ZHL-16C without gradient factor customization and no GPS or offline maps. The Suunto D5 ($700-850) offers similar dive features but uses the older RGBM algorithm and has a smaller display. The Garmin Descent Mk2S ($1,000-1,200) adds extensive sports features but costs more than twice as much. For divers specifically wanting a dedicated dive computer with technical capability in watch format, the Nautic S offers compelling value. You’re getting trimix support, Bühlmann 16 GF with customizable gradient factors, GPS, and excellent battery life for half the price of the Ocean or Garmin competitors. The trade-off is no sports modes, no heart rate sensor, and no smart notifications.

Our Professional Opinion

The Nautic S hits a sweet spot that makes a lot of sense: dedicated dive computer with serious technical capability in a comfortable watch package at a reasonable price. The bright AMOLED display with sapphire crystal is genuinely premium. The 60-hour battery life eliminates charging anxiety on dive trips. Bühlmann 16 GF with customizable gradient factors addresses Suunto’s historical algorithm conservatism and enables team diving compatibility. The trimix support with full decompression planning in a $499 watch-sized computer is impressive. The GPS and offline maps add genuine utility for dive travel. On the flip side, this is a brand new model that just launched in December 2025, so long-term reliability is unproven. The lack of heart rate monitoring and sports modes means it’s purely a dive computer that happens to look like a watch, not a dual-purpose device like the Ocean. And while Suunto has improved, their customer service reputation still trails Shearwater in the diving community.

Final Recommendation

Buy the Suunto Nautic S if you want a dedicated dive computer with technical capability in a comfortable, wearable watch format at a competitive price. It’s ideal for recreational divers progressing into nitrox and multi-gas diving who want room to grow without spending $1,000+. The computer works perfectly for dive professionals who want a reliable, capable daily dive computer that can handle both recreational instruction and personal technical dives. It’s also excellent for divers who split time between scuba and freediving, as the dedicated freediving mode works well. The Bühlmann 16 GF algorithm makes it suitable for team diving with buddies on Shearwaters or other computers. Skip it if you want an all-in-one device with sports tracking, heart rate monitoring, and smart notifications; the Ocean delivers all that for $400 more and makes sense if you’ll actually use those features. Also pass if you prioritize brand reputation and established customer service, as Shearwater still holds the edge there. And if you’re purely recreational and won’t use multi-gas or technical features, simpler computers like the Suunto Zoop Novo or Mares Puck Pro offer better value for basic diving.