Abstract: An all-in-one combination layout tool is provided for marking center lines for spacing studs, marking rip lines, marking cut lines for roof rafters and staircase stringers, and other purposes. The tool comprises a rectangular base plate, an elongate locator bar with a rounded pivot corner, and two connectors to connect the locator bar to the base plate in a variety of configurations. The base plate includes multiple “pivot” points for pivotally connecting the locator bar, two strategically-placed arcuate slots for marking or making angle cuts, and two strategically placed parallel slots for configuring the tool to mark or make rip cuts. Angle markings are provided on two adjacent edges of the base plate, and 1/16-inch markings are provided on the opposite adjacent edges. The base plate is planar and has no enlarged flange or lip that would hinder its use in laying out staircase stringers.