Apple Watch Ultra for Scuba Diving: What It Can and Can't Do

Can you scuba dive with an Apple Watch Ultra?

Yes, to 40 m (130 ft), if you are a trained recreational diver. That limit comes from Apple and applies to every Ultra model. Apple's user guide says Ultra models should only be used by trained divers for recreational dives of 40 m or less, with a buddy, and that the watch works as a dive computer only through a compatible third-party app. Apple Watch Series 10 and later can run those apps too, but only to 6 m (20 ft), which in practice means snorkeling.

So there are two pieces of software to understand. Apple's own Depth app shows depth, time and water temperature. A dive computer app adds the decompression model, alarms and planning. Apple names Oceanic+, made by Huish Outdoors, on its Ultra spec pages, so that is the app covered here, using Apple's and Oceanic's own documentation. For how any dive computer handles decompression, browse our dive computer and decompression guides.

What do the 100 m rating and EN 13319 actually mean?

They are two different tests, and neither is the divers' watch standard. Apple rates the Ultra line water resistant to 100 m under ISO 22810:2010 and calls it EN 13319 compliant. ISO 22810 is the general standard for water-resistant watches, and its own scope says divers' watches are covered by a separate standard, ISO 6425. Apple does not cite ISO 6425 for the Ultra.

EN 13319 is the European standard for diving depth gauges and combined depth and time measuring devices. It deals with how depth and dive time are measured. Information on decompression obligations is excluded from its scope, so compliance tells you nothing about the quality of any app's decompression advice.

The 100 m figure is a water-resistance rating, not a diving depth. For diving, the number that counts is 40 m. Apple says that below it some functions may stop working or work intermittently. Oceanic+ shows a red alarm once you pass it, then stops displaying no-decompression data, and Oceanic tells you to end the dive safely, switching to a backup computer if needed.

What does the built-in Depth app do?

It is a depth gauge with a timer and a thermometer. One screen shows the time, current and maximum depth, time underwater and water temperature. With Auto-Launch on, it starts when you pass 1 m for more than 5 seconds. It can also start from the Action button. A session ends once the watch has been out of the water for 10 minutes, and a descent inside those 10 minutes is added to the same dive.

Apple is explicit that Depth is not a dive computer: no decompression stop information, no gas analysis, no other recreational scuba functions. It keeps a dive summary on the watch for 7 days. The full history sits in the Fitness app on the iPhone, which also collects dives logged by third-party apps.

One rule catches divers who start a trip on Depth and move to a dive computer app later. Apple warns against switching to a different diving app within 48 hours of your last dive, because apps may not share dive data and can miscalculate tissue loading. Oceanic confirms that nitrogen from dives in Depth is not carried into Oceanic+. You cannot swap in the water either: Oceanic says you have to exit Depth at the surface first. Choose the app before the first dive of the trip and stay with it.

How Oceanic+ works as a dive computer

Oceanic+ runs the Bühlmann ZHL-16C decompression model with gradient factors, the family explained in our dive computer algorithms guide. Oceanic points out that its dedicated computers use its DSAT and Z+ models instead, so an older Oceanic unit may show different no-decompression times on the same dive.

Conservatism has three presets: 0 (the default and least conservative), +1 and +2. A fourth option sets custom gradient factors, which Oceanic recommends only with proper training. The FAQ does not list the gradient factor pairs behind the presets.

Underwater the touchscreen is locked. You scroll screens with the Digital Crown, and the Action button sets a compass heading and dismisses yellow warnings. Red alarms cannot be dismissed. What the app shows and enforces, according to Oceanic:

• No-decompression time, shown as 100+ above 100 minutes, plus a tissue bar graph that turns yellow near the limit.
• Decompression stops once you pass the limit, with the ceiling and a countdown on the variometer.
• Ascent rate on the variometer, which turns red above 9 m (30 ft) per minute.
• A 3-minute safety stop at 5 m (15 ft), lengthened after a missed stop or an ascent violation.
• Time to surface: ascent at 9 m per minute plus any decompression and the 3-minute stop.
• No-fly time of 12 hours after a single no-decompression dive, 18 hours after repetitive dives, 24 hours after decompression dives and 48 hours if a stop was missed. Oceanic says this follows DAN; our flying after diving post covers the guidance itself.

Which Oceanic+ features need a paid plan?

Scuba mode itself. The free Basic plan covers depth, time, compass, snorkel sessions and a gauge mode, but it has no scuba mode and no dive planner, and its logbook holds 12 entries before new ones overwrite the oldest. Decompression tracking on the watch requires the Scuba Diving plan, which also includes freediving.

One subscription covers all of your own devices: the Ultra, and an iPhone in Oceanic's dive housing, which is rated to 60 m (196 ft). A single watch cannot be shared between divers, because a dive computer tracks one person's tissue loading. If a paid plan lapses, Oceanic says your full logbook stays accessible for 12 months. Oceanic's plan page tells you to check the app for regional prices; the figures below are from the US App Store listing.

Does it support nitrox, gas switching or air integration?

Nitrox, yes. Air integration, no. Oceanic's feature page lists air or nitrox up to 40%, and the app asks you to confirm nitrox training before the setting becomes available. Oceanic calls a ppO2 of 1.4 the recognised standard for recreational diving.

Version 4.0, released in March 2026, added multi-gas management: up to three tanks, each with its own mix, MOD and a ppO2 limit between 1.4 and 1.6. Oceanic's FAQ says mixes up to 100% oxygen can be set and that the app never switches gas on its own, even when it suggests a better one. The same FAQ still says elsewhere that Dive Mode is limited to air or nitrox to 40%. Check which version is on your watch before you plan a gas switch around it. Trimix is not supported, and the 40 m limit stays in place whatever you breathe.

There is no link to a tank transmitter. Asked whether a wireless transmitter can be connected, Oceanic's answer is no. The watch cannot read your tank pressure or estimate remaining gas time, so the pressure gauge on your regulator stays essential.

How long does the battery last on a dive day?

Neither Apple nor Oceanic publishes a runtime for dive mode. Apple's battery figures describe a mixed day of normal use: up to 42 hours for the Ultra 3. That figure is measured with a set mix of time checks, notifications, workouts, sleep tracking and connectivity, listed in Apple's footnotes, and none includes diving.

Diving changes the load. Oceanic+ switches the display to always-on in dive mode, and a two- or three-dive day adds up to hours of it. Start each dive day with a charged watch and check the level between dives. Oceanic recommends rinsing the watch in fresh warm water and drying it completely before you charge it.

What is the Apple Watch Ultra not suitable for?

Anything outside recreational no-decompression diving on air or nitrox to 40 m. Apple's and Oceanic's documentation rule out the following:

• Dives deeper than 40 m (130 ft). Oceanic says to use a different backup device on any dive that goes below that depth.
• Trimix and technical diving. Dive Mode does not support trimix.
• Monitoring tank pressure. There is no transmitter support.
• Diving it as your only instrument. Apple's warning is to always carry a secondary depth gauge and timer or watch, as well as decompression tables such as the DECO 2000 table.
• Lending it to another diver, or swapping diving apps within 48 hours of a dive.
• Diving with a cracked display or back crystal. Apple says cracks can let water in under pressure, and water resistance diminishes over time.
• Untrained divers, and nitrox without a nitrox certification.
• Water colder than 0 °C (32 °F) or warmer than 40 °C (104 °F), the stated operating range.

Should it be your first or only dive computer?

It can be your first. It should not be your only instrument, because Apple itself tells you to carry a backup. Within its limits you get a Bühlmann computer with nitrox, conservatism settings, an ascent rate alarm and a logbook, on a watch you already wear every day.

The costs and trade-offs are different from a dedicated unit. The scuba plan is a recurring $79.99 a year in the US, or $4.99 a day for a single trip. The battery needs daily charging on a dive trip. There is no air integration. And the seals take everyday knocks between trips, which is why Apple offers a seal test for the Ultra. Run it through the same checklist as any other option in our first dive computer guide: readable screen, conservatism you understand, nitrox, and a plan for what happens if it stops working mid-dive.