The #1 psychrometric chart software tool in the world used by 20,000+ engineers.
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HVAC noise prediction and acoustical analysis.
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Commercial and residential HVAC load calculations.
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... and many more desktop apps. Click here for the entire list.

Bob Hanna founded Hands Down Software in 1987 and developed the current Windows version of HDPsyChart in the mid-1990s. Since then, over 20,000+ engineers, manufacturers, data center managers, and building owners have relied on this software for their psychrometric calculations.

In the Spring of 2024, Carmel Software acquired Hands Down along with the psychrometric chart, HVAC acoustical analysis, HVAC load calculations, clean room design and other software tools. Click here for details on that acquisition.