A rebalancing device for rebalancing of an underwater vehicle comprises at least one thruster and at least one storage space. The rebalancing device comprises control circuitry. The control circuitry is configured to receive sensor data comprising information relating to a depth and an attitude of the underwater vehicle, and thruster data comprising information relating to thrust and orientation of thrust of the at least one thruster. The control circuitry is further configured to determine a difference between a centre of gravity, CoG, of the underwater vehicle and a centre of buoyancy, CoB, of the underwater vehicle based on the sensor data and the thruster data, and to determine a difference between a gravitational force acting on the underwater vehicle and a buoyancy of the underwater vehicle based on the sensor data and the thruster data.