A stepwise and stepless adjustable square for use in carpentry, comprising: a stock; a blade rotatable relative to the stock around an axis of rotation; a first alignment structure adapted to rotate rigidly with the stock around the axis of rotation; a second alignment structure complementary to the first alignment structure and adapted to rotate rigidly with the blade around the axis of rotation; a spring device which in conjunction with a spring expansion-restricting element of the adjustable square is adapted to axially press the second alignment structure towards the first alignment structure, wherein the spring expansion-restricting element is rigidly connected to the first alignment structure; and a knob operatively connected to the first alignment structure and movable between a first position and a second position, wherein in the first position the first alignment structure and the second alignment structure at certain angles between the stock and the blade align and engage such that a force of the spring device is reduced compared to the force at angles where the first and second alignment structures do not align for stepwise adjustment, and wherein in the second position the first alignment structure is moved axially away from the second alignment structure such that the first and second alignment structures are separated from each other and such that the spring device due to the likewise moved spring expansion-restricting element is compressed and urges a first surface associated with the blade into frictional engagement or into stronger frictional engagement with a second surface associated with the stock for stepless adjustment. a stock; a blade rotatable relative to the stock around an axis of rotation; a first alignment structure adapted to rotate rigidly with the stock around the axis of rotation; a second alignment structure complementary to the first alignment structure and adapted to rotate rigidly with the blade around the axis of rotation; a spring device which in conjunction with a spring expansion-restricting element of the adjustable square is adapted to axially press the second alignment structure towards the first alignment structure, wherein the spring expansion-restricting element is rigidly connected to the first alignment structure; and a knob operatively connected to the first alignment structure and movable between a first position and a second position, wherein in the first position the first alignment structure and the second alignment structure at certain angles between the stock and the blade align and engage such that a force of the spring device is reduced compared to the force at angles where the first and second alignment structures do not align for stepwise adjustment, and wherein in the second position the first alignment structure is moved axially away from the second alignment structure such that the first and second alignment structures are separated from each other and such that the spring device due to the likewise moved spring expansion-restricting element is compressed and urges a first surface associated with the blade into frictional engagement or into stronger frictional engagement with a second surface associated with the stock for stepless adjustment.