Japanese version and translation details.

Carpalx optimizes keyboard layouts to create ones that require less effort and significantly reduced carpal strain!

Download keyboard layouts, or run the code yourself to explore new layouts.

X11 layouts are available! Many thanks to Sven Hallberg for providing X11 configuration for Carpalx layouts. Richard Gomes contributed an archive of these files for KDE/Gnome users.

Love your coworkers? Switch them to QWKRFY layout or a fully optimized QGMLWY layout.

Hate your coworkers? Switch them to TNWMLC layout. It's the only keyboard layout that has its own fashion line.

Have ideas? Tell me.

12/feb/14 - Added evaluation of the abKey layout. Its alphabetic layout makes no attempt at ergonomics. Detailed statistics are available.

QWERTY Layout

This page introduces how the typing effort model is used to measure the typing effort of a specific keyboard layout. I also introduce the concept of model parameter sets - specific combinations of model parameters that apply different weights to components of the model.

QWERTY - by default

The majority of keyboards in English-speaking countries are arranged according to the QWERTY keyboard layout. Patented in 1868 by Christopher Sholes, this layout was designed to limit the speed of the typewriter operator to avoid the typebars from intertwining. If you ever used a manual typewriter, in which each key is linked to a lever bearing the corresponding character (a typebar), you have likely experienced the mechanical limitation of the design. Jamming on the keys is fun, but not productive if you need to get words on a page.

A small fraction of users have the comfort of using a Dvorak layout. Although many QWERTY users have heard of the Dvorak alternative and, in principle, appreciate the benefits of this layout, few have made the switch. The lack of adoption of Dvorak is due to the inherent difficulty and frustration in retraining muscle memory.

Figure 1 | The QWERTY keyboard layout describes the key arrangement on the majority of English keyboards. The purpose of this layout was originally to limit typing speed on mechanical typewriters. QWERTY is not only counterproductive but arguably harmful to people who spend their days at a keyboard. This layout should be deprecated.

QWERTY - typing effort

Typing effort is broken down into three components: base effort (finger distance), penalties (hand, row and finger penalties) and stroke path (relative position of successive key strokes). The table below breaks down the typing effort for the QWERTY layout. The model parameters were chosen to make QWERTY effort components each 1.000, for easy comparison with other layouts.

QWERTY typing effort - english corpus
model keyboard total effortrel% effort contributionsrel%
base penalties path
mod_01 qwerty 3.000

1.00033.3
1.00033.3
R0.408
F0.408
1.00033.3

The colored bars in the table represent in absolute and relative terms the total effort and individual effort contributions from base, penalty and path components. Below is an explanatory legend.

Both the absolute and relative values of the efforts in this table depend on the choice of model parameters. The values aren't therefore interesting by themselves, until you compared them with values for other layouts, such as Dvorak or optimized QWERTY. Comparison of efforts for different layouts can be made only for the same parameter set model.

The breakdown of the penalty components deserves some mention. You will notice that the sum of the penalty components (row and finger effort) is not equal to the total penalty. This is due to the non-linear nature of the penalty definition. There are cross-terms in the definition of the penalty effort component, which causes the total penalty value to be larger than the sum of its individual components. In other words, if we add the row penalty (calculated in the absence of finger penalty) to the finger penalty (calculated in the absence of row penalty), their sum will be smaller than the total penalty (calculated with row and finger penalties enabled).

Migrating from QWERTY

qwerty to dvorak

QWERTY is not an optimal layout (many argue it is not even a good layout) and there are compelling reasons to migrate away from QWERTY. Currently typists have two popular options: Dvorak and Colemak. The typing effort reduction in moving to Dvorak is 30%. Each effort component for Dvorak is lower. The finger component of the penalty is higher, due to Dvorak's increased use of the pinky (18% of keystrokes vs 10% on QWERTY are done by the pinky), which can be seen by a +56% increase in the finger penalty over QWERTY. If you have very weak pinkies, Dvorak may not be for you.

Dvorak certainly does a good job in lowering the base effort &mdash this is the component of effort that measures finger travel distance &mdash by moving frequently used keys, such as vowels, to home row. Because Dvorak vowels are serviced by the same hand, hand-alternation is increased (one-character hand run is 62% for Dvorak and 51% for QWERTY), a desirable property of an efficient layout.

QWERTY vs Dvorak typing effort - english corpus
model keyboard total effortrel% effort contributionsrel%
base penalties path
mod_01 qwerty 3.000

1.00033.3
1.00033.3
R0.408
F0.408
1.00033.3

dvorak 2.098 (-30.1)

0.39718.9 (-60.3)
0.93744.7 (-6.3)
R0.171 (-58.1)
F0.638 (+56.4)
0.76536.5 (-23.5)

qwerty to colemak

The Colemak effort has an even lower effort than Dvorak and it achieves this by further lowering all three components of the effort. It significantly decreases the penalty component seen in Dvorak. Thus, although Colemak's finger penalty is still higher than QWERTY (again, through the increased use of the pinky), but overall penalty is lower by 24%.

QWERTY vs Colemak typing effort - english corpus
model keyboard total effortrel% effort contributionsrel%
base penalties path
mod_01 qwerty 3.000

1.00033.3
1.00033.3
R0.408
F0.408
1.00033.3

colemak 1.842 (-38.6)

0.34418.7 (-65.6)
0.76341.4 (-23.7)
R0.158 (-61.3)
F0.487 (+19.4)
0.73539.9 (-26.5)

qwerty to qwkr**

If a committment to Dvorak seems too radical, you can adopt a partially modified layout which mitigates the major problems of QWERTY. This layout was identified by performing 5 key swaps on QWERTY that resulted in the largest reduction of typing effort. This layout belongs to the QWKR** layout family, which rival Dvorak. QWKR** layouts embody some the virtues of Dvorak without the radical adjustment to most key locations.

QWERTY - detailed statistics

In addition to evaluating components of typing effort (base, penalties and stroke path), Carpalx evaluates a keyboard for its finger, hand, and row usage frequency and runs (details).

Below is a table that details characteristics of typing an English training set on a QWERTY keyboard. It is noteworthy that QWERTY has a very high top-row usage frequency - 51% of the keystrokes use the top row and only 34% use the home row. QWERTY heavily favours the left hand, with a hand asymmetry of left-right=0.15. The weaker pinky and ring fingers make up 32% of the keystrokes, making QWERTY inefficient at using the stronger index and middle fingers.

The cumulative run distributions are best analyzed when compared with another keyboard layout such as Dvorak.

carpalx effort optimization keyboard name statistics effort
rowh rowb hand asym finger freq cumulative run distribution mod_01
none QWERTY standard
QWERTYUIOP[]\
ASDFGHJKL;'
ZXCVBNM,./
0.34 0.15 0.15 0.10 0.21 0.27 0.42
1 2 3 4 5 6 7 8 9
rhl 0.42 0.69 0.83 0.91 0.95 0.97 0.99 0.99 1
rhr 0.61 0.83 0.94 0.98 0.99 1 1 1 1
rh 0.51 0.76 0.88 0.94 0.97 0.98 0.99 1 1
rrt 0.55 0.78 0.91 0.96 0.98 0.99 1 1 1
rrh 0.68 0.91 0.97 0.99 1 1 1 1 1
rrb 0.94 1 1 1 1 1 1 1 1
rr 0.68 0.88 0.95 0.98 0.99 1 1 1 1
rf 0.89 0.99 1 1 1 1 1 1 1
rj 0.68 0.83 0.94 0.96 0.99 0.99 1 1 1
3

QWERTY - word difficulty

Using the typing effort model described in Carpalx - Typing Effort, I ranked 6-12 character words by their corresponding effort (effort is normalized to word length) using a dictionary of 480,000 words (/usr/share/dict/words, Red Hat 4 Enterprise). Below is a table that shows sets of words representing effort percentiles.

QWERTY MOD_01 ENGLISH Word Efforts
average effort percentile wordeffort
7.2 hardest pazazz8.2 pazazzes8.1 tazzas7.9 zaqaziq7.5 pizzazzes7.5 pizzazz7.4 bezazzes7.3 azazel7.2 zaqqum7.1 gozzan7.1 bezazz7.1 mazzard7.1 hazzan7.1 pizazzy7.0 pizazzes7.0 razzed7.0 piazzas7.0 razzes6.9 pappox6.9 pizzas6.9 ezzard6.8 poppas6.8 cozzes6.8 cazzie6.8 razzer6.8
3.9 90% acrotomous3.9 ammonolysis3.9 antilopine3.9 cocteau3.9 overcommand3.9 parthenopean3.9 pentanol3.9 pointes3.9 pretaped3.9 trappistes3.9 unprovised3.9
3.6 80% armipotent3.6 champine3.6 chemotropism3.6 dextrogyre3.6 mangroves3.6 pentacosane3.6 piquancies3.6 subtenure3.6 tormentress3.6 trentonian3.6 unproviding3.6
3.4 70% brainerd3.4 brethel3.4 metamale3.4 nephelometer3.4 nicostratus3.4 overwrited3.4 pathways3.4 petrogenic3.4 rayonne3.4 scabies3.4 unbegotten3.4
3.3 60% anthranil3.3 athonite3.3 declensional3.3 dirtbird3.3 kipling3.3 missample3.3 nephrogenous3.3 obsequiosity3.3 outfaced3.3 preached3.3 unrepugnant3.3
3.2 50% bachelorhood3.2 embordering3.2 hemelytra3.2 ingent3.2 limnery3.2 octosyllabic3.2 pignorative3.2 sumphishly3.2 unclinched3.2 undermined3.2 urinated3.2
3.0 40% accusers3.0 clincher3.0 disoperation3.0 drachen3.0 handcraft3.0 horripilant3.0 leegte3.0 mercantilely3.0 phyllite3.0 samaritans3.0 sillock3.0
2.9 30% actuarial2.9 chapelled2.9 haurient2.9 lepisosteus2.9 letgame2.9 mesognathous2.9 racketeers2.9 redbelly2.9 sepulchred2.9 tensileness2.9 unroyalist2.9
2.7 20% chorussed2.7 epistolise2.7 epistolist2.7 fluxer2.7 gooseflower2.7 hydrotype2.7 lasslorn2.7 micelles2.7 religionless2.7 schanz2.7 selene2.7
2.5 10% alleges2.5 cedarkey2.5 ciderist2.5 drearies2.5 farron2.5 graford2.5 neodadaism2.5 niderings2.5 refuting2.5 turkestan2.5 unvulgarise2.5
0.9 easiest fiddly0.8 jiffle0.8 diddly0.8 dekker0.9 dukker0.9 kajdan0.9 dukkha0.9 duffle0.9 hadjis0.9 fluffy0.9 kakkak1.0 kiddle1.0 siddhi1.0 duffie1.0 fiddle1.0 fuddle1.0 fuffle1.0 fliffus1.0 ejidal1.0 koffka1.0 diddle1.0 duddle1.0 duffau1.0 khadis1.0 duffles1.0 kiddie1.0