What can the OVM Dive Mixer calculate?

The mixer calculates donor-to-target tank pressure transfer, top-off blend results, and trimix fill pressures.

Can I use this as a trimix blending calculator?

Yes. The trimix tool helps estimate required O2, He, and air pressures to reach a target blend and final pressure.

Is the dive gas mixer free to use online?

Yes. OVM Dive Mixer is free and available online as part of OVM Dive Planner.

Free Dive Gas Mixer: Trimix, Nitrox & Tank Fill Calculator

Dive Gas Mixer and Fill Calculator

Use this dive gas mixing calculator to estimate tank pressure transfer, top-off blend outcomes, and trimix fill steps. It is designed for divers who need quick gas planning support for nitrox, trimix, and routine cylinder blending workflows.

Tank Fill Calculator (Boost)

Calculate the final pressure when filling from a donor tank to a target tank.

Donor Tank Volume (L): Donor Tank Pressure (bar): Target Tank Volume (L): Target Tank Starting Pressure (bar):

Top-Off Blend Calculator

Calculate the resulting gas mix composition after topping off with a different gas.

Starting Mix

O₂ (%): He (%): Starting Pressure (bar):

Top-Off Gas

O₂ (%): He (%):

Final Pressure (bar):

Trimix Mix Calculator

Calculate the required pressures for O₂, He, and air to achieve a target trimix starting from an initial mix.

Target Mix

Desired O₂ (%): Desired He (%): Target Final Pressure (bar):

Current Mix (Starting Point)

Current Pressure (bar): Current O₂ (%): Current He (%):

Gas Mixing FAQ

How do I calculate tank fill from a donor cylinder?

Use the Tank Fill tab and enter donor volume, donor pressure, target volume, and target starting pressure.

Can I estimate final nitrox after top-off?

Yes. In Top-Off Blend, enter starting mix, top-off gas mix, and final pressure to see resulting O2, He, and N2 percentages.

Can this page help with trimix blending sequence?

Yes. The Trimix Mix Calculator outputs required O2 and He additions and the remaining air top-off to target pressure.