The transconductance of a MOSFET is an important design parameter for CMOS design. This parameter and the threshold voltage form a pair of parameters that almost all CMOS design is based on. Signal Processing Group Inc. released a javascript calculator to calculate this parameter for quick CMOS design that can be trimmed to a final design using some nth order simulator. Hand calculations lay the foundation for design and providing a starting point for the designer. Please visit the SPG website for more options and information.