Dissolved Oxygen Saturation
Calculate the saturation concentration of dissolved oxygen in water based on temperature and salinity, and determine the percent saturation of a measured DO sample.
Dissolved Oxygen Saturation
intermediateCalculate DO saturation concentration and percent saturation
Formula
DO_sat = f(temp, salinity)
Scenario A
How It Works
Dissolved oxygen solubility decreases with increasing temperature and salinity. This calculator uses the APHA (American Public Health Association) empirical formula to compute saturation concentration.
DO_sat = 14.652 − 0.41022T + 0.007991T² − 0.000077774T³ − S × 0.006
% Saturation = Measured DO / DO_sat × 100
Example
Freshwater at 20°C has a DO saturation of ~9.1 mg/L. If you measure 7.0 mg/L:
DO_sat(20°C, 0 PSU) = 9.1 mg/L
% Saturation = 7.0/9.1 × 100 = 76.9%
Frequently Asked Questions
What is a healthy DO level for aquatic life?
For most fish, DO should be above 5 mg/L or >80% saturation. Levels below 3 mg/L stress fish, and below 2 mg/L is lethal for most species.
Why does salinity affect DO?
Dissolved salts occupy space in water, reducing the available volume for oxygen molecules. Seawater at 35 PSU holds about 20% less oxygen than freshwater at the same temperature.
Save Configuration Snapshot
Save current parameters to your dashboard for instant one-click reloading.
About This Calculator & Guide
About the Dissolved Oxygen Saturation Calculator
The Dissolved Oxygen Saturation Calculator is a specialized online utility designed to help you calculate dissolved oxygen saturation concentration and percent saturation based on water temperature and salinity. free online do calculator. It performs calculations in real-time to provide immediate, reliable estimates for study, work, or daily tasks.
How to Use
Simply enter your parameters in the input fields of the calculator widget above. The tool evaluates the inputs instantly and displays the results in real-time. You can modify any value to check alternate scenarios and compare figures dynamically.
Data Privacy & Safety
All calculations are executed locally within your web browser. No inputs are sent to our servers or stored externally, ensuring your personal and financial details remain completely private and secure.
FAQ
Frequently Asked Questions
What does the Dissolved Oxygen Saturation Calculator do?+
Calculate dissolved oxygen saturation concentration and percent saturation based on water temperature and salinity. Free online DO calculator. It is designed for quick everyday use and gives clear results without requiring a sign in.
Is the Dissolved Oxygen Saturation Calculator free to use?+
Yes. The Dissolved Oxygen Saturation Calculator is free to use online and works directly in your browser.
Can I use the Dissolved Oxygen Saturation Calculator on mobile?+
Yes. The calculator layout is responsive, so you can use it on phones, tablets, laptops, and desktop screens.