Abstract: An electronic calculator with a time display function which is operable in either a calculator mode, a clock mode or a world clock mode is disclosed. The calculator includes a calculator section for performing basic arithmetic calculations. An input unit is provided for supplying input data and country codes to the calculator section and a time unit signal generator is provided for supplying a time unit signal to the calculator section. The calculator section includes an arithmetic part for carrying out at least the four basic arithmetic calculations; a memory part for storing the output of the arithmetic part, a control part for controlling the arithmetic part and the memory part, and a common display for displaying the contents of the memory.