# DTS Gas Guru — CCR & Trimix Gas Calculator > Technical diving calculator for gas mixes, MOD, END, and EAD. (iPhone/iPad app by William Goodman.) - Source: https://appshunter.io/ios/app/dts-gas-guru/id6761082629 (this page in markdown: same URL + `.md`) - Developer: [William Goodman](https://appshunter.io/developer/1887704117) - Category: Utilities, Sports - Price: $4.99 - Age rating: 4+ - Requires: iOS 15.6 · 4 MB - Languages: American English - Released: 2026-03-26 - Data updated: 2026-09-03 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/dts-gas-guru/id6761082629/reviews.md ## What is DTS Gas Guru? The DTS Gas Guru is a professional technical diving tool built for CCR and open circuit divers. Designed for real-world diving, Gas Guru delivers fast and accurate calculations for Best Mix, MOD, END, EAD, gas density, and gas mixing with costing — all in one clean, reliable interface. Whether you're planning deep trimix dives, analysing gas mixes, or checking safe operating limits, Gas Guru helps you make confident decisions underwater, built on the same dive-physics engine that powers DTS Dive To Survive. WHAT'S IN THE TOOLKIT • Best Mix — ideal O2/He blend for your target depth, PO2, and END (OC + CCR diluent) • Gas Check — verify a fill against your PO2 limit or CCR setpoint, with MOD, END and density • Mixer — Nitrox and Trimix blending, top-up planning, "what if" scenarios, decant calculations • Density — gas density at depth against caution and critical thresholds, with adjustable water temp factored in • Turn Pressure — quick turn-pressure calculations • Min Gas — minimum gas reserve calculations SAVE AND SYNC YOUR MIXES Create a free account to sync your saved gas mixes across all your devices. Your data is end-to-end encrypted before it leaves your device. Gas Guru works fully offline; an account is only needed for cloud sync. CLEAN, FOCUSED, NO ADS No clutter, no ads, no distractions — just the numbers you need before you get in the water. DESIGNED FOR • Technical divers • CCR divers • Trimix divers • Dive professionals and instructors Built from real-world diving experience — not just theory — Gas Guru provides practical tools you can rely on when it matters most. Plan it. Trust it. Dive it. ## Key features - MOD, END, EAD calculations - Best Mix calculator - Gas density with temperature adjustment - Gas mixing with adjustable O₂ purity - CCR diluent analysis - Trimix and Nitrox support ## Recent user reviews (2 of 2) All indexed reviews: https://appshunter.io/ios/app/dts-gas-guru/id6761082629/reviews.md ### 5/5 — Great little gas planning app *2026-03-29* This a smashing little utility for planning and mixing OC and CCR gases. All the information needed in one place including PPO2, END and temperature variable Gas Density. Calculate your best mix based on these criteria and then use the app to mix it. All this in an intuitive, easy to use, modern interface. **Developer response:** Thank you so much for your review! im very happy that you like it and im happy to listen to any suggestions for improvement. Safe Diving ### 5/5 — Black Water Tek Gas Guru *2026-03-29* This app just solved all the problems I never knew I had🤿 Game changer. **Developer response:** Fantastic ! Thank you so much for your review. Im happy to hear that its of use to you !! ## Frequently asked questions about DTS Gas Guru ### What is DTS Gas Guru used for? DTS Gas Guru is a professional technical diving tool that provides fast and accurate calculations for dive planning, gas analysis, and determining safe operating limits for CCR and open circuit divers. ### What types of dives does DTS Gas Guru support? DTS Gas Guru supports Trimix and Nitrox dives, making it versatile for various technical diving scenarios. ### How accurate are the calculations in DTS Gas Guru? The app is designed for real-world diving and delivers fast, accurate calculations, including a Best Mix calculator that avoids rounding errors. ### Is DTS Gas Guru available on Android? DTS Gas Guru is currently supported on iPhone and iPad devices. ### How much does DTS Gas Guru cost? DTS Gas Guru is a paid application, priced at $4.99. ### When was DTS Gas Guru last updated? The latest version, Gas Guru 1.7, was last updated on May 3, 2026. ### What is the age rating for DTS Gas Guru? DTS Gas Guru has an age rating of 4+, making it suitable for a wide range of users. ### Does DTS Gas Guru have ads? No, DTS Gas Guru does not contain advertisements. ## Version history (last 5 releases) ### Gas Guru v2.3.3 — 2026-08-28 This update collects everything since 2.1.0, including two fixes reported by customers. DECIMALS WORK ON EVERY KEYBOARD If your phone's number pad types a comma rather than a full stop, decimals silently did nothing — you could not enter an analysed 31,4% O2, a fill pressure, a cylinder size or a limit. Both separators are now accepted everywhere in the app. FILL TO ANY PRESSURE The "fill to" fields carried a 50 bar floor that rewrote what you typed as you typed it, so a 20 or 40 bar stage could not be entered at all. The floor is gone. Stage, travel and bailout bottles fill to whatever you ask for. BLENDING DOES NOT VENT GAS IT DOES NOT NEED Fill recipes could prescribe a bleed on a cylinder that only needed topping up — in one reported case three bar of nitrox vented to move the mix two tenths of a percent, and in another a bleed of a tenth of a bar for a mix that analyses the same either way. Once a recipe reaches the mix you ordered, it now keeps your gas. Where no recipe reaches it, accuracy still comes first. NEW: SEMI-CLOSED (SCR) LOOP GAS CALCULATOR Inspired loop O2, PO2, loop drop from supply, MOD and loop density, for both constant mass flow (CMF) and passive addition (PSCR) — they are different equations and are dangerous at opposite ends of a dive, so the architecture is chosen explicitly and never assumed. It is a gas calculator, not a dive planner: it does not produce a decompression schedule or a bailout plan. Where the loop falls below a breathable fraction, it says so rather than reporting a clamped number as a real one. ONE MIX LIBRARY A saved gas used to be filed under a role, so the same 21/35 had to be saved separately to be usable as a bottom mix, a bailout and a diluent. The library is now just a list of gases, and every tool offers all of it. CLEARER FIRST RUN The welcome guide now describes Gas Guru's own tools rather than the DTS dive planner's screens, and the safety notice covers what a gas calculator actually carries: every figure here is a calculation, not a measurement. Plus readability fixes across the tools, including the SCR loop-type control, where the second option could be pushed off the edge of the screen on a phone. Always analyse a cylinder before you breathe it, and label it with what the analyser reads. ### Gas Guru v2.1.0 — 2026-08-09 Gas mixing is substantially improved. Fill steps are now whole bars you can stop a valve on, every plan shows the mix you will actually get rather than the one you asked for, and a blend that cannot be made says so instead of printing a recipe. Bleeds are planned and priced, with the fill pressure that would avoid them. Sign in and gas mix sync now work reliably. An account stays optional: the calculator works in full without one. Also: refreshed header, smaller download, various fixes. ### Gas Guru v2.0.3 — 2026-07-30 Gas mixing - Nitrox now blends the full 21-100% O2 range: EAN50, EAN80 and pure O2 - MOD and density corrected for high-O2 deco mixes - New cylinder picker with a twin toggle for any cylinder Planning - Your PO2 limits now drive every MOD shown - Labels print the PO2 the MOD was figured at - Salinity: Fresh, EN13319, Salt (matches Shearwater) - CCR setpoint switches at target depth, then low SP to surface - Deco switch time now affects the schedule - Corrected Simple Thirds turn pressure ### Gas Guru 2.0.2 — 2026-07-23 What's New in 2.0.2 Gas Mixer: Nitrox blending now supports the full 21–100% O₂ range, so you can mix EAN50, EAN80, and pure O₂ deco gases directly (previously capped at 40%) Fixed MOD and gas density readings for high-oxygen deco mixes CCR diluent recommendations are now correctly capped at 21% O₂ Turn Pressure: Simple Thirds and Cave Thirds now use their correct, distinct calculations Fixed cylinder label placement in Best Mix and Gas Check Renamed "Dive Monitor" to "O₂ Toxicity Tracking" for clarity Sign-in is no longer required to use the app — create a free account only if you want cloud sync General bug fixes and stability improvements ### 2.0.1 — 2026-07-17 Fixed: changing the app language now translates the full gas calculator toolkit (Best Mix, Gas Check, Mixer, Turn Pressure, Min Gas, SCR) — previously only the menu translated. Fixed: Gas Cost calculator now supports all currencies correctly, including larger-denomination currencies like Rupiah and Yen. Improved: Mixer result panels (Nitrox, Trimix, Top Up, What If) now consistently show MOD at your configured END limit and MOD at PO₂ 1.4, instead of a single ambiguous MOD figure. Restored the original launch screen color. General bug fixes and stability improvements. ## Related topics [dts gas guru](https://appshunter.io/ios/topics/dts-gas-guru) · [gas guru](https://appshunter.io/ios/topics/gas-guru) --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-09-03.*