Abstract: Rip guide for tools comprising a guide member adapted to slide along an edge of a work piece such as a sheet of plywood.A slotted scale member having a guide end and a tool mounting end is adjustably mounted on the guide member.A saw mounting member is rotatably mounted on the tool mounting end of the scale member. The tool mounting member is adapted to be clamped to a conventional tool.The scale member has a transverse slot adjacent to its tool mounting end, the slot being adapted to receive a razor type knife for cutting plaster board parallel to the edge of the cutting piece.The scale member also has at least one hole adjacent to its tool mounting end to receive a marking member for marking the work piece parallel to the edge of the work piece.The scale member has a hole located a predetermined distance from the guide, the hole being adapted to receive a marker member for marking the work piece parallel to the edge of the work piece.