SLX is a compressed file that stores data in XML and uses Unicode UTF-8 encoding, generated using MathWorks Simulink. SLX files contain simulation data used by scientist and engineers around the world. MathWorks Simulink software is used by such companies as Huawei or Fujitsu.

SLX format was developed in 2012 to replace older MDL format. Simulink designed its MathWorks software for efficiency and user-friendliness bu offering such features ad smart editing system, work schedules, and real-time modeling.