Time to Surface – Deco Planner
Trimix, nitrox dive calculator
About
This technical dive planner calculates staged decompression for dives up to 56 meters. It supports multiple bottom gases and one deco bottle, offering detailed gas planning, runtime tracking, and contingency solutions. The app also accounts for repetitive dives and provides a printable wetnote layout.
What's New in Time to Surface
1.8.2
October 28, 2026
Your settings and your last dive setup follow you to your other devices through iCloud. When a newer setup arrives from another device, the plan page offers it with one tap and never changes what you are looking at on its own. Metric or imperial is one choice for Time to Surface and Turn Pressure: change it in one and the other follows. Names you remove from the team list on Send for signatures stay removed on your other devices. An older edit made offline never replaces a newer one, for briefs, plans, signatures, your sites and your divers. A diver changed on two devices keeps both changes, such as a new name on one and a new SCR on the other. A diver's SCR history is now a chart with a scale, dates and a point for each measurement.
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FAQ
What is the maximum depth Time to Surface can plan for?
Time to Surface can plan staged decompression for dives from 15 meters up to 51 meters. For depths deeper than 51 meters, up to 56 meters, it will plan and warn rather than refuse, as gas density becomes a limiting factor before oxygen toxicity at these depths.
What types of gases does Time to Surface support?
The app supports six different bottom gases, including EAN32, triox 30/30, EAN28, air, 21/35, and 18/45. It also accommodates one decompression gas, either EAN50 or oxygen, in various cylinder sizes (AL80, AL50, or AL40).
Can Time to Surface plan for repetitive dives?
Yes, Time to Surface can plan for repetitive dives. You can save previous dive plans and input the surface interval before the current dive. The app then calculates the impact of nitrogen and helium crossover and CNS decay on your decompression profile.
Does Time to Surface offer contingency planning?
Yes, the app provides contingency planning. It can recalculate dive plans if you lose your deco bottle, add five minutes to your bottom time, or go three meters deeper. If your planned cylinders cannot support a contingency, the app will indicate this.
What dive model does Time to Surface use?
Time to Surface uses the Bühlmann ZH-L16C model. Users can adjust the gradient factors, with a default setting of 20/85. The app also allows for adjustable ppO2 limits and descent rates for customized planning.
How does Time to Surface handle the last part of the dive?
The app plans the final 6 meters of ascent at a rate of 1 meter per minute. It also offers an optional 'Pragmatic Decompression' mode that linearizes stops between 21m and 9m for a simpler in-water profile, though the unadjusted profile is generally more conservative.
Is Time to Surface available on multiple devices?
Based on the provided data, Time to Surface is currently supported on iPhones. Information regarding Android or other platform availability is not specified.
How often is Time to Surface updated?
The latest version of Time to Surface is 1.5, which was last updated on September 19, 2026. The release date for this version was September 1, 2026, indicating relatively frequent updates.
