Descent Mk2S Scuba Diving Computer Review: Tracks Heart Rate and Blood Oxygen Levels Underwater

The Descent Mk2S in Short

Garmin Descent Mk2S tracks up to 30 hours of dive mode battery life for scuba divers who need a reliable watch-style dive computer.

The Descent Mk2S provides 7 days of battery life in smartwatch mode, allowing you to transition from your daily routine to the water without a recharge. This versatility makes it a multi-use tool for the active user.

This specific model features a 1.2 inch color display and supports Garmin Pay for contactless payments. It holds a 4.8 average across 305 ratings, which is the 2nd most of the 15 screened scuba diving computers.

We evaluated 15 scuba diving computers and selected this model for a full review because it is one of the most-rated products that pass screening, with at most 2 per brand. This review is for the user who needs a dive computer that functions as a primary smartwatch.

The Short Answer on the Descent Mk2S

Best for: you need a versatile dive computer that also functions as a high-end smartwatch for daily tracking and music storage.

The Garmin Descent Mk2S is a capable choice at the $649.99 price point.

• Pro: It includes music storage and streaming support for use during surface activities.
• Pro: The 30-hour dive mode battery life allows for a full day of snorkeling.
• Pro: It features a 1.2 inch color display and wrist-based heart rate sensing.
• Con: The 30-hour dive mode battery limits its use for long-distance multi-sport triathlons lasting over 27 hours.
• Con: The 10.6 ounce weight is significantly heavier than many standard sports watches.

Don’t buy this if: you require a battery life exceeding 30 hours in dive mode for extended underwater operations.

Price assessment: The $649.99 price is premium for a device that balances specialized diving sensors with general smartwatch features.

For advanced gas management, see our list of the best dive computer for nitrox.

Technical Specifications for this Scuba Diving Computer

Battery Life measures the total duration of continuous power supply, and the Descent Mk2S provides up to 30 hours in dive mode.

Before You Buy: Underwater Computer Checklist

The first thing to check is the dive mode battery life to ensure it covers your planned underwater duration.

• ☐ Confirm the dive mode runtime—the Descent Mk2S provides up to 30 hours—to ensure you do not run out of power mid-dive.
• ☐ Verify the 1.2 inch screen size—the display is 1.2 inches—to ensure the interface is large enough for your visibility needs.
• ☐ Check the weight—the unit weighs 0.3 kilograms—to ensure the watch is not too heavy for your wrist during long sessions.
• ☐ Verify the storage capacity—the device holds 200 dives—to ensure you do not run out of memory for your dive logs.
• ☐ Confirm the dimensions—the watch measures 1.69 x 1.69 x 0.56 inches—to ensure the housing fits comfortably on your wrist.

You should not buy this product if you require a battery life that exceeds 30 hours in dive mode, as the device will not support longer continuous underwater operations.

You need to know if your current accessories will fit before purchasing the Descent Mk2S. The Descent Mk2S is QuickFit band compatible, which means it uses a standard quick-release system for swapping straps. You can use existing bands as long as they are designed for the QuickFit system; if they are not, you will need to purchase new straps to secure the watch.

What the Numbers Mean in Use

Wrist-Based Heart Rate and Pulse Ox Sensing

The Descent Mk2S provides wrist-based heart rate sensing and Pulse Ox sensing (a sensor that measures blood oxygen saturation) to monitor your physiological data during and between dives. These sensors allow you to track your heart rate and oxygen levels directly from your wrist, removing the need for additional chest straps or separate armbands for basic monitoring. These features provide a continuous stream of data that helps you monitor your physical response to exertion or environmental changes.

The Descent Mk2S supports altitude acclimation, which uses these sensors to help your body adjust to changes in elevation. Because the device includes Pulse Ox sensing, you can monitor your blood oxygen saturation, which is a key metric for staying within safe limits during high-altitude activities. These sensors provide the data required to monitor your physical state, though the specific rate of change or accuracy levels are not stated in the specifications.

Six Dive Modes with ABC Sensors

The Descent Mk2S offers six dive modes and includes ABC sensors (an altimeter, barometer, and compass) to provide essential underwater data. These sensors provide the data for an underwater compass and altitude acclimation, helping you maintain orientation and track your depth. The six dive modes allow you to configure the device for different types of underwater tasks, ensuring the interface provides the relevant information for your specific activity.

You can store up to 200 dives on the wrist, which provides enough local memory to log an entire trip without needing to sync the device immediately. For long-distance multi-sport triathlons, the 30-hour battery life in dive mode supports between 14 and 27 hours of continuous use depending on your specific power requirements. This storage capacity and battery life ensure the device remains functional through extended sessions and multiple dives in a single day.

Smartwatch Features and Music Storage

The Descent Mk2S includes music storage with streaming service support and the Garmin Pay payment service for use when you are on the surface. These features allow you to manage media and make payments directly from the watch, functioning much like a smartphone on your wrist. The 1.2 inch color display provides the visual interface for these applications, while the QuickFit band compatibility ensures the watch remains secure during both active use and everyday wear.

The device provides up to 7 days of battery life in smartwatch mode, which is sufficient to stay on the surface for a full day of snorkeling. While the 30-hour dive mode battery is the primary limit for underwater work, the 7-day smartwatch endurance allows for extended periods of surface-level use. This distinction ensures you have the power for your primary dive task while maintaining the ability to use smart features throughout the day.

Common Buyer Jobs Checked Against the Descent Mk2S’s Specs

The Descent Mk2S against the jobs buyers ask about, worked out from its listed battery life and a typical need for each job.

How the Descent Mk2S Compares to Alternatives

The Descent Mk2S ranks first in our comparison with a 4.8 average across 305 buyer ratings.

• The Garmin Descent Mk2i Titanium with Black Band offers 80 hours of battery life in dive mode, which is 50 hours longer than the 30 hours provided by the Descent Mk2S.
• The Shearwater Research Teric Color Wrist Dive Computer is $69.99 cheaper than the Descent Mk2S.
• The Garmin Descent G1 010-02604-01 costs $160 less than the Descent Mk2S.
• The Garmin Descent G2 46mm Paloma is $160 cheaper than the Descent Mk2S.
• The Wearable4U Garmin Descent G1 Solar 010-02604-00 is $160 cheaper than the Descent Mk2S.
• The Descent Mk2S holds the highest rating of the six options we compared.

If you require the longest possible battery life for extended underwater stays, the Garmin Descent Mk2i Titanium with Black Band is the better pick.

New divers can learn how a scuba diving computer works before making a purchase.

Consider exploring scuba diving computer alternatives if you prefer different monitoring methods.

How the $649.99 price point compares to other dive computers

The Garmin Descent Mk2S sits at the $649.99 mark, which is $100 above the $550 average for the similar scuba diving computer products we compared. At this price point, you receive a dedicated dive computer with a 1.2 inch color display, 30 hours of battery life in dive mode, and a 4.8 rating from 305 buyer ratings. You are paying for the integration of smart features like music storage and Garmin Pay alongside the core underwater functionality.

This product is the right buy if you require a device that can stay on the surface for a full day of snorkeling, as the 30-hour dive mode capacity supports a 12-hour session even at the heavier end of usage. If your requirements are strictly limited to basic depth and time tracking, you may find the $649.99 price point high compared to entry-level models.

Getting the Descent Mk2S Working, and What to Check After

Getting Your Descent Mk2S Ready

You need a compatible power source to charge the internal battery before the Descent Mk2S is ready for use.

1. Unpack the watch and the included charging cable.
2. Connect the charging cable to the watch and a power source to replenish the internal power source.
3. Sync the watch with the Garmin Dive app to ensure the 200-dive storage and navigation features are active.
4. Verify the QuickFit band is secured to the correct size before your first dive.

Warranty and Support: What to Check

Warranty coverage and support terms differ by seller and country.

• Confirm the screen’s 1.2 inch display is free of cracks to ensure the dive computer remains functional.
• Check that the 30-hour dive mode battery life accurately reflects your expected underwater duration to prevent power loss.

Test the Descent Mk2S in a shallow pool and verify all six dive modes function as expected the day it arrives while a return is still possible.

What Buyers Still Want to Know About This Scuba Diving Computer

How long does the Garmin Descent Mk2S battery last?

The Descent Mk2S provides up to 30 hours of battery life in dive mode, which allows for a full day of snorkeling lasting up to 24 hours. For standard use, the device holds a charge for up to 7 days in smartwatch mode or 6 hours when using GPS with music.

Does the Descent Mk2S support music?

Yes, the Descent Mk2S supports music storage and streaming services. This feature allows you to listen to music directly from the watch while using its various sports apps.

What is the screen size on the Descent Mk2S?

The Descent Mk2S features a 1.2 inch color display. This screen size provides a compact interface for viewing dive data and smartwatch notifications on your wrist.

Can I use the Descent Mk2S for multi-sport triathlons?

The Descent Mk2S can track a long-distance multi-sport triathlon for up to 14 to 27 hours depending on your specific power requirements. It includes support for multiple sports apps and advanced training features to monitor your progress.

Is the Descent Mk2S Right for You?

Who the Descent Mk2S suits and the jobs it is the wrong choice for, listed below with the reason for each.

Where to Buy This Scuba Diving Computer

The Descent Mk2S sat at $649.99 in the listing data from November 2026; the price you see at checkout can differ.

Scuba diving computers are sold by the retailers below – we do not track which of them has the Descent Mk2S in stock, so check availability and the current price with the retailer before making a trip.

• REI (online and physical stores) — reliable inventory of major brands and in-store expert advice
• Amazon (online only) — massive selection and easy comparison of consumer models
• ScubaGear (online only) — specialist retailer with deep technical inventory
• Triton Sports (online and physical stores) — specialist retailer with expert staff and technical gear
• DiveInn (online only) — large online catalog for international and domestic brands
• Dick’s Sporting Goods (online and physical stores) — wide availability of mainstream brands and physical locations

Final Verdict on the Descent Mk2S

If you need a device that can stay on the surface for a full day of snorkeling, the Descent Mk2S is a viable option. The 30 hours of battery life in dive mode provides enough power to cover a 12-hour snorkeling session even at the heavier end of expected usage.

You should choose this scuba diving computer if your priority is a multi-sport capable device that also handles underwater tracking. The Descent Mk2S offers a 1.2 inch color display and supports several sports apps alongside its six dive modes. It features Pulse Ox sensing for blood oxygen saturation and altitude acclimation, which are useful for high-altitude diving and general fitness tracking.

The Descent Mk2S includes a surface GPS for estimated entry and exit points and an underwater compass. It provides storage for up to 200 dives on the wrist and features ABC sensors to monitor your environment. With a weight of 0.3 Kilograms and dimensions of 1.69 x 1.69 x 0.56 inches, it maintains a compact profile for a watch-style dive computer.

The 4.8 rating from 305 buyer ratings serves as a significant signal of user satisfaction for this model. At the $649.99 price point, it positions itself as a versatile tool for those who need both a dedicated dive computer and a high-end smartwatch.

You should choose the Descent Mk2S if you require a versatile tool that balances dedicated diving features with advanced training and music playback capabilities. It is a practical choice for the $649.99 price point when you need a single device to handle both underwater and land-based sports.

The 4.8 average across 305 buyer ratings highlights the reliability of the device for those who need a multi-functional dive computer.

Skip it if: You require a battery that can power a continuous 20-hour multi-sport triathlon, as the 30-hour dive mode limit may not cover the entire duration at the upper end of power usage.

You can also find the best scuba diving computer with gps for navigation-heavy dives.