Abstract: The character input device (5) (i) determines an input candidate that is a character string to be inputted at an input position on a basis of a character string before the input position, (ii) causes a display screen to display a candidate selection key to which the determined input candidate is assigned in such a manner as to allow a user to select the candidate selection key, and (iii) when the displayed candidate selection key is selected, inputs at the input position the character string of the input candidate assigned to the selected candidate selection key, the character input device including a first candidate determination section (38) for assigning a Caps key to the candidate selection key, a second candidate determination section (39) for assigning a Done key to the candidate selection key, and an editing candidate determination section (40) for assigning a Clear key to the candidate selection key. This allows determining an input candidate with high probability.