An adjustable drill jig system for drilling holes in a workpiece includes a first T-shaped element having a stem and a crossbar; a first guide engaged with the stem, the first guide having a stop plate extending perpendicular to the stem; a double bracket having a first channel and a second channel, the first channel to engage with the crossbar; an extension ruler engaged with the second channel of the double bracket and extending away from the cross bar; and a second guide having a drill bushing; the second guide is to engage with the crossbar or the extension ruler for placement of the drill bushing; and the adjustable drill jib system allows for drilling one or more holes in the workpiece.