Numeric keypads usually operate in two modes: when Num Lock is off, keys 8, 6, 2, 4 act like arrow keys and 7, 9, 3, 1 act like Home, PgUp, PgDn and End; when Num Lock is on, digits keys produce corresponding digits. On Apple Macintosh computers, which lack a Num Lock key, the numeric keypad always produces only numbers. The Num Lock key is replaced by the Clear key.

The arrangement of digits on numeric keypads is different from that of telephone Touch-Tone keypads, have the 1-2-3 keys on top and 7-8-9 keys on the third row, instead of the reverse used on a numeric keypad. It is thought that the layout was arranged this way for the early telephone keypads so that the addition of the alphabetical characters found on most telephones followed the digits numerically.[citation needed] This layout, which matches most modern calculators and cash registers, may be confusing for those who use one of these arrangements more often.

Numeric keypads are useful for entering long sequences of numbers quickly, for example in spreadsheets, financial/accounting programs, and calculators. Input in this style is similar to that of a calculator or adding machine.

## Measuring speed

Ten key speed is measured in Keystrokes per Hour (KPH). The minimum required speed for many data entry jobs is around 9000 KPH with good accuracy. A speed of 12,000 is considered excellent.[5]

## Chinese input methods

The numeric keypad is used by some systems for input of Chinese characters, for example CKC Chinese Input System and Q9 input method.

## Computer games

A 104-key PC US English QWERTY keyboard layout with the numeric keypad at the far right.

Numeric keypads are also used for playing some computer games where the player must control a character, for example roguelikes. Unlike arrow keys, the numeric keypad allows diagonal movement. For keyboards without a numeric keypad, some games provide alternative movement keys, such as classic Rogue's HJKL keys.

The numeric keypad can also be an alternative for navigation in computer gaming from the WASD keys. The mouse would be used in the left hand instead of the right.