Mixxx
Mixxx is a free and open-source DJ software that offers a wide range of features, including beat matching, looping, effects, and sampling. It is available for Windows, macOS, and Linux.
Virtual DJ
Virtual DJ is a popular DJ software that offers both a free and a paid version. The free version includes many of the features found in the paid version, such as beat matching, looping, effects, and sampling. Virtual DJ is available for Windows, macOS, and Linux.
Audacity
Audacity is a free and open-source audio editor that can also be used for DJing. It offers basic DJing features such as beat matching, looping, and effects. Audacity is available for Windows, macOS, and Linux.
Traktor DJ 2
Traktor DJ 2 is a free DJ software from Native Instruments. It offers a limited set of features compared to the paid version of Traktor, but it is still a powerful and capable DJ software. Traktor DJ 2 is available for Windows and macOS.
Serato DJ Lite
Serato DJ Lite is a free DJ software from Serato. It offers basic DJing features such as beat matching, looping, and effects. Serato DJ Lite is available for Windows and macOS.
These are just a few of the many free DJ mixing professional software programs that are available online. With a bit of research, you can find the right software to meet your needs and budget.