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Computer keyboard designed with ergonomic considerations

An ergonomic keyboard is a computer keyboard designed with ergonomic considerations to minimize muscle strain, fatigue, and other problems.

The common QWERTY keyboard layout is credited to the mechanical typewriter designed by C. Latham Sholes and patented in 1878; research indicates the layout may have been influenced by telegraph operators. The offset in the columns between rows was designed to accommodate the physical links between each key and the internal mechanisms of the typewriter; as typing duties transitioned to electric (motorized) typewriters and then computers, the layout was retained to ease the transition for users that had already been trained to type. However, the legacy mechanical layout has numerous idiosyncrasies, including the staggered column layout, which can force the user into uncomfortable, repetitive movements and postures. Several potential solutions have been proposed since at least 1926. Ergonomic keyboards, in essence, are created with the aim of minimizing discomfort in users' wrists and reducing unnecessary finger movements by rearranging or repositioning the keys. For instance, typing on a conventional keyboard layout can force the user into shoulder elevation, wrist ulnar deviation, and head rotation. A more detailed study was published in 1972 by Kroemer, suggesting that an adjustable split keyboard may reduce user pain. During the 1970s, several studies were published suggesting that data entry operators were at risk of developing musculoskeletal injuries. On the other hand, adjustable split keyboards sometimes intimidate potential users, who may fear they may exacerbate or become more susceptible to repetitive strain injuries; fixed split keyboards like the Microsoft Natural have sold well in comparison. The angled split keyboard (sometimes referred to as a Klockenburg keyboard) is similar to a split keyboard, but the middle is tented up so that the index fingers are higher than the little fingers while typing. Key Ovation makes the Goldtouch ergonomic keyboard which is an adjustable angled split keyboard. On some ergonomic keyboards, the tenting angle is increased to 90° so the user types with their hands perpendicular to the ground, thumbs up, similar to the hand position adopted by accordion players.

Because electric typewriters and computer keyboards no longer need to accommodate a mechanical linkage, the keys can be set in vertical columns without staggering, minimizing lateral finger movements when moving between rows. This vertical layout rearranges the keys into linear columns. If the rows remain aligned horizontally, the resulting ortholinear layout puts the keys on an orthogonal grid. Other designs use vertical columns with staggered rows to compensate for the difference in finger lengths. A keyboard with vertical columns can require an adjustment period as the user retrains their finger movements. ErgoDox (adjustable split, staggered rows), ZSA Moonlander, and Zergotech Freedom (adjustable split, semi staggered rows) keyboards.

The preceding split and vertical column keyboards arranged each key cluster onto a single flat plane. Contoured or dished surface keyboards like the Maltron (1977) or the newer Kinesis Advantage line (1992+) are fixed split keyboards with tenting that place the keys into two curved depressions set approximately at shoulder width. The function keys, navigation keys, and modifiers such as , , etc. are set between the key groups for use with the thumbs. For these keyboards, the resulting bowl like key surfaces are intended to minimize and make consistent the finger extension required to strike keys away from the home row. In general, contoured keyboards also incorporate a vertical column layout with staggered rows for each hand. In this configuration, minimal movement of arms and wrists is required. Some keyboards combine vertical key columns and contoured surfaces with fully adjustable (independent) split key clusters. Examples include the Kinesis Advantage 360, Dactyl Manuform, and MoErgo Glove80. With a relatively small market, many are custom built or sold as kits to be assembled by the user, with extensive customization options.

Handheld ergonomic keyboards are designed to be held like a game controller, and can be used as such, instead of laid out flat on top of a table surface. They allow the user the ability to move around a room or to lean back on a chair while also being able to type in front or away from the computer. Some variations of handheld ergonomic keyboards also include a trackball mouse that allow mouse movement and typing included in one handheld device.

A few ergonomic keyboards do not have the typical one key per letter, such as a keyer or a keyless ergonomic keyboard. For example, DataHand eliminates the need for any wrist motion or finger extension; each finger has five separate switches triggered by buttons or paddles. Advances in speech recognition have made it possible to eliminate the use of a keyboard altogether, particularly on smaller devices that lack traditional keyboard interfaces.

It is widely claimed that an ergonomic keyboard may reduce muscle strain and reduce risk of carpal tunnel syndrome or other kinds of repetitive strain injury. With respect to "split" keyboards, quality studies that demonstrate injury reductions are lacking, with the exception of physically split keyboards which have "sharply angled keyboard faces". There is evidence, however, that such keyboards are not well tolerated. Narrow studies examining hand position at rest neglect many other possible factors. For example, one should be aware that the effect of “ergonomic” keyboards is to change the musculoskeletal region exposed to risk, instead of eliminating hazardous postures.