A keyboard for one-handed data input is disclosed. The keyboard includes a primary keypad including a first set of keys. The primary keypad is defined by a first side and an opposed second side. The keyboard also includes an auxiliary keypad including a second set of keys, as well as an input selection pad with a multiple position switch. The switch is used to selectively map the keyboard to various input value sets. The auxiliary keypad is attached to the first side, while the input selection pad is attached to the second side. There is also a rest pad centrally mounted to the primary keypad.