A removable die of a joining tool comprising a die head having an upper side, a bottom side and a die shaft extending from the bottom side and receivable and lockable in a die dome without rotation. The die shaft comprises: at least one first radial web forming an axial undercut on two sides by which the die shaft is lockable in the die dome by a linear inserting movement, at least one second exposed radial web, the radial length of which is adaptable to a diameter of the die dome to ensure a lateral guiding of the die shaft in the die dome and which is arranged between the die head and the first radial web, and an ejection surface by which the removable die can be moved out of the die dome and which is arranged at the free end of the die shaft opposite to the die head.