Input/Output port configurations using multiplexers are described herein. An example computing system includes a multiplexer having a first input, a second input, and an output. The computing system also includes a first channel connecting the first input to a first host controller, the first host controller to transfer data at a first speed, and a second channel connecting the second input to a second host controller, the second host controller to transfer data at a second speed higher than the first speed. The example computing system further includes a third channel connecting the output to a port, the port to receive a connector of an electronic device, and a line selector to, based on a type of the electronic device connected to the port, configure the multiplexer to electrically couple the output to the first input or the second input.