A fence jig is provided for assisting construction of privacy fences. The fence jig includes an elongated board that is the length of a fence post. Attached to that board is a post guide that fits on the fence post. First, second, and third flanges are attached to the board with dimensions that place gaps between the flanges where fence connectors should be located when the post guide rests on a fence post. The fence jig also provides reference edges and power saw cutting guides for accurately cutting fence panels.