A method for calculating a crane capacity for a crane having a variable position counterweight at a locked position includes determining a boom combination and determining a maximum capacity at a hook position for the boom combination. A maximum target value for an operating condition dependent on a balance of the crane is determined. An indication of the locked counterweight position is received. At least one new target value for the operating condition dependent on the balance of the crane between the variable position counterweight at the locked counterweight position is established. A new capacity of the crane is calculated by decrementing the maximum capacity of the crane proportionally to a difference in the maximum target value and the at least one new target value. Cranes and crane control systems may employ this method.