While (and the newer version 10.0) is a paid product from NIST, they do offer a free alternative called mini-REFPROP . This sample version is designed primarily as a teaching tool for students learning thermodynamics.
Unlocking Fluid Properties: Is There a Free Version of REFPROP?
If you're convinced that CoolProp is the right path for you, here’s how to get started and where to find other free resources. refprop 91 free
NIST software is protected by copyright law. Using an unauthorized copy in a commercial environment or academic publication can lead to steep fines, legal action, and the retraction of research papers. Legitimate Ways to Access REFPROP
REFPROP | NIST - National Institute of Standards and Technology While (and the newer version 10
While the desire for free access to this powerful tool is understandable, downloading cracked or "free" versions of REFPROP 9.1 poses severe risks. Why Is REFPROP Not Free?
Released in 2013, is a sophisticated database and computer program designed for Windows. It holds critically evaluated mathematical models that represent the most accurate available data for industrial applications. Key features of version 9.1 included: If you're convinced that CoolProp is the right
REFPROP (Reference Fluid Thermodynamic and Transport Properties) is a critical software database developed by the National Institute of Standards and Technology (NIST) . It is the gold standard for engineers and researchers who need accurate thermodynamic properties—such as density, viscosity, enthalpy, and vapor pressure—for pure fluids and mixtures.
CoolProp is an open-source, free, C++ library that provides property data similar to REFPROP. It is a highly respected alternative that supports numerous languages (Python, Excel, MATLAB, etc.) and uses similar high-accuracy equations of state. Why You Should Use the Current Version (10)
EES is a commercial engineering tool that includes a fluid property library similar to REFPROP. The version allows you to solve small problems and access most fluid properties, though the number of data points is limited.
💡 For high-stakes engineering, rely on a licensed copy or use CoolProp as a reliable, free, and legal substitute. If you’re interested, I can help you: Set up CoolProp in Excel or Python Find the official NIST purchase page Compare RefProp vs. CoolProp for your specific project