A device for balancing a turbomachine rotor having a driver rotor and a driven rotor is provided. The device comprises a base that is coaxially fixable to the turbomachine rotor and configured to transfer torque from the driver rotor to the driven rotor. The device also comprises at least three balancing tools arranged on the base, each balancing tool (i) defining a respective balancing direction along a radial direction of the base and (ii) comprising: a weight moveable along the respective balancing direction, and a motor configured to move the weight along the respective balancing direction to balance the rotor.