Refprop 91 [extra Quality] Free -

NIST does not offer the full version of REFPROP 9.1 or its successor, REFPROP 10, for free. The software requires a paid license to support ongoing research and database maintenance.

Have you found a legitimately free alternative to REFPROP? Share your experience in the comments below (or on engineering forums like Eng-Tips). But do not ask for cracks – we do not allow piracy. Stay safe and engineer responsibly.

While the full version of REFPROP 9.1 is a paid resource, NIST offers a student version known as REFPROP Mini . refprop 91 free

Is this for an or commercial product design ?

The current standard release (Version 10) costs $325.00 for a single-user license. NIST does not offer the full version of REFPROP 9

RefProp (REFPROP) is a property-reference program from NIST for calculating thermophysical and transport properties of pure fluids and mixtures (gases and liquids) using advanced equations of state and mixture models. REFPROP 9.1 refers to a specific past release of that software.

Many universities and educational institutions have site licenses. If you are a student or a professor, you likely have access to REFPROP through your university’s software portal at no cost to you personally. Check with your IT department or engineering library before attempting to find unauthorized versions online. Share your experience in the comments below (or

Both Mini-REFPROP and CoolProp offer Excel add-ins. Once installed, you can call functions directly inside spreadsheet cells (e.g., =PropsSI("D", "T", 298.15, "P", 101325, "Water") ) to automate your engineering calculations without manual data entry. Summary of Options Fluid Selection Best Use Case Comprehensive (100+ fluids + mixtures) Commercial engineering & research Mini-REFPROP Limited (Water, CO2, Methane, etc.) Academic learning & basic tasks NIST WebBook Broad (Browser-based tables) Quick data lookup CoolProp Free / Open-Source Comprehensive (120+ fluids + mixtures) Coding, automation, & Excel work

While searching for "REFPROP 9.1 free" often leads to unofficial or trial versions, it is important to distinguish between the full commercial software and the legitimate free options provided by (National Institute of Standards and Technology). The Reality of "Free" REFPROP 9.1