A multiturn rotary encoder includes a singleturn code disk which is joined in rotatably fixed manner to a shaft and which has a code track that is scannable by a singleturn scanning unit to ascertain the absolute position within one revolution of the shaft, a multiturn unit for measuring revolution data which are suitable for ascertaining the number of revolutions performed by the shaft, and an evaluation unit which is connected to the multiturn unit via at least two digital interfaces for transmitting the revolution data. The revolution data include at least two data words which have a different rate of change during rotation of the shaft, the interface for transmitting the data word having the highest rate of change to the evaluation unit is a parallel interface, and the interface for transmitting the data word having the lowest rate of change to the evaluation unit is a serial interface.