An assembly for measuring torque and/or axial load for capping heads includes a containing body torque and/or load sensor housed within the body, and an interface that connects a capping head to the body. The interface is coupled to the torque/load sensor to transfer torque applied on the interface to the torque sensor and/or to transfer load applied on the interface to the load sensor. The interface has a first part fixedly constrained to the capping head such that the first part is brought into rotation and/or translation by the capping head, and a second part coupled to the torque sensor for transferring a torque thereto and/or to the load sensor for transferring a load thereto. The torque and/or load are applied by the first part to the second part and the first part transfers a torque to the second part in the absence of a reciprocal contact.