CDK may refer to:
- Curses Development Kit, an open source library of ncurses widgets written by Mike Glover and Thomas Dickey.
- Curses Development Kit, an open source library of ncurses widgets developed by Vexus.
- Chemistry Development Kit, an open source chemical expert system for Chemoinformatics and Bioinformatics, written in Java.
- Cyclin-dependent kinase.
- George T. Lewis Airport, located in Cedar Key, Florida.
- The theoretical decay of the speed of light or C-decay.
- Can't Drift Kerny, written by T1zzzz