QSFP loopback adapter modules are used for testing QSFP ports on system boards and QSFP switches. The electrical loopback provides a cost effective method for QSFP port testing. Transmitting data from the host is electrically routed (internally to the loopback module) to the receiving data outputs and back to the host. Since the QSFP loopback module does not contain laser diodes or photodiodes, it provides a very cost-effective way to test QSFP ports.