A radius adjustable compass is provided to enable a user to adjust a radius easily and exactly. A radius adjustable compass comprises the following units. A pair of legs(100) are combined with the each other in a V shape. An elastic body(200) is installed to have force of restitution. A loop(300) placed in an arbitrary location of the legs is used for adjusting an interval of the legs. The elastic body is positioned between the legs. The legs have a groove(110) accommodating the loop in a position of contacting the loop.
展开▼
