A power conversion device is configured to convert power-over-Ethernet (PoE) power to universal serial bus (USB) power to yield a USB charging port. The conversion device can conform to a number of modular and/or portable form factors, allowing existing Ethernet data ports to be easily converted to USB charging ports. Embodiments include a modular conversion device configured to mount in a window of an existing wall plate as a replacement for an unused Ethernet data port, and a portable conversion device that can be plugged into an existing Ethernet data port. The conversion device receives PoE power from the Ethernet network, converts the PoE power to an appropriate USB standard, and delivers the power to an integrated USB charging port.