The search for —NIST’s industry-standard Reference Fluid Thermodynamic and Transport Properties database—is common among engineering students, researchers, and HVAC professionals. However, because this is a proprietary software developed by the National Institute of Standards and Technology (NIST), finding a "free" version comes with significant caveats.
If your project mandates official NIST data, you must purchase a legal license for the current version (REFPROP 10). refprop 91 free
Go to coolprop.org/downloads/ Step 2: Download the "CoolProp for Windows (Standalone GUI)." This is an .exe file that looks and feels similar to REFPROP’s interface. Step 3: Install it (no admin rights needed, no malware). Step 4: Select a fluid – say, "Water" or "R134a." Step 5: Input temperature and pressure. CoolProp returns density, enthalpy, entropy, viscosity, and thermal conductivity. Step 6 (Advanced): For mixtures, use the Python interface: from CoolProp.CoolProp import PropsSI and PropsSI('H','T',300,'P',101325,'R32&R125') Go to coolprop
, with upgrades from older versions (like 9.x) costing around Version Status : Version 9.1 has been officially superseded by Version 10 CoolProp returns density