Nitrox MOD Calculator

MOD stands for Maximum Operating Depth. Use this tool to calculate safe depth limits for specific nitrox blends and partial pressures of oxygen (pO₂), and view a reference table for common blends.

Calculate Your MOD

Select your nitrox blend (22%–40%).

1.4 ATA is standard, 1.6 ATA is contingency only.

34 m

(112 feet)

* MOD = [(pO₂ / (O₂ fraction)) - 1] × 10
Always round down and follow agency guidelines.

Disclaimer: This calculator is a professional dive planning tool. Always verify calculations with dive computers and instructors.
Important: This is not a substitute for proper Nitrox training.

MOD Reference Table

Blend (% O₂)MOD at 1.4 ATA
(ft / m)
MOD at 1.6 ATA
(ft / m)
29126 ft (38 m)149 ft (45 m)
30121 ft (37 m)143 ft (43 m)
31116 ft (35 m)137 ft (42 m)
32111 ft (34 m)132 ft (40 m)
33107 ft (33 m)127 ft (39 m)
34103 ft (31 m)122 ft (37 m)
3599 ft (30 m)118 ft (36 m)
3695 ft (29 m)113 ft (35 m)
3792 ft (28 m)109 ft (33 m)
3889 ft (27 m)106 ft (32 m)
3985 ft (26 m)102 ft (31 m)
4082 ft (25 m)99 ft (30 m)

MODs below 29% exceed recreational depth limits of 130 ft (40 m).

How to Set Up Nitrox on Popular Dive Computers

Always consult your device manual and double-check your settings before diving. Tap a device for setup steps:

Note: Always refer to your manufacturer's manual for the most accurate and up-to-date instructions.

Further Training & Resources