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In Windows there is a program called Keyboard Jedi that shows what keys are pressed on the keyboard.

Is there an equivalent for Linux?

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11 Answers 11

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Others have mentioned xev, which is good when you're running X11. When you're at the console, however, showkey is what you want.

And if you’re at an SSH session or a real terminal, you can use /usr/lib/ncurses/examples/demo_altkeys (available in Debian in the ncurses-examples package).

Note that xev for "a" gives 38, while showkey for "a" gives 30, because xev reports scancodes, whereas showkey by default reports keycodes.

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  • 5
    Neither work in SSH terminal. Commented Nov 8, 2015 at 11:23
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    @ChristianHujer, -X -Y means X11 forwarding (stackoverflow.com/questions/13425820/…). There is no X11 server on my machine (I use PuTTY), so xev doesn't apply, and showkey gives Couldn't get a file descriptor referring to the console. Commented Jan 10, 2017 at 12:15
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    to work around showkey giving the error about not getting a file descriptor (like in comment by @anatolytechtonik ), try sudo showkey Commented Mar 27, 2017 at 22:38
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    @Johann xev reports scancodes whereas showkey by default reports keycodes. sudo showkey -s reports scancodes. Commented Oct 17, 2017 at 9:01
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    Only showkey -a works over an SSH PTY or a serial terminal (/dev/ttyS_n_). It's sensible, as the scancode/keycode/emission byte sequence is handled on the client end, in the TTY emulator (or hardware, if you're a fan of Retrocomputing.SO). You put these sequences into .inputrc for e.g. bash, and other readline-happy stuff. The remote X stuff works differently: [e.g., Windows-based] X server has access to your raw keyboard (Windows reserves some chords, tho), and sends scancodes. Over ssh -Y or TCP, all the same. There's also the terminfo DB (demo_altkeys), but this margin is too narr.. Commented Jun 6, 2021 at 20:22
90

Also screenkey, a screencast tool that displays keys being pressed on-screen.

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    I tried this and it didn't show me keys like volume up/down. Commented Nov 30, 2015 at 12:39
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    For me, this shows both brightness and volume adjustments. Great little program overall! Commented Dec 1, 2016 at 13:34
  • The version in Debian Stretch repositories is ancient (and Stretch is stable for only, idk, 2 months maybe?). Use the Github version to get some settings.
    – Luc
    Commented Oct 3, 2017 at 23:27
  • Repo was migrated to Gitlab.
    – rkta
    Commented Jul 16, 2019 at 17:59
45
 chris@retina:~$ xinput list
 ⎡ Virtual core pointer                     id=2    [master pointer  (3)]
 ⎜   ↳ Virtual core XTEST pointer               id=4    [slave  pointer  (2)]
 ⎜   ↳ bcm5974                                  id=13   [slave  pointer  (2)]
 ⎜   ↳ Logitech Unifying Device. Wireless PID:1028  id=9    [slave  pointer  (2)]
 ⎣ Virtual core keyboard                    id=3    [master keyboard (2)]
     ↳ Virtual core XTEST keyboard              id=5    [slave  keyboard (3)]
     ↳ Power Button                             id=6    [slave  keyboard (3)]
     ↳ Power Button                             id=7    [slave  keyboard (3)]
     ↳ Sleep Button                             id=8    [slave  keyboard (3)]
     ↳ FaceTime HD Camera (Built-in)            id=11   [slave  keyboard (3)]
     ↳ Apple Inc. Apple Internal Keyboard / Trackpad    id=12   [slave  keyboard (3)]
     ↳ daskeyboard                              id=10   [slave  keyboard (3)]
     ↳ daskeyboard                              id=14   [slave  keyboard (3)]
 chris@retina:~$ xinput test 14
 key release 36 
 key press   43 
 hkey release 43 
 key press   26 
 ekey release 26 
 key press   46 
 lkey release 46 
 key press   46 
 lkey release 46 
 key press   32 
 okey release 32 
 key press   37 
 key press   54 
 ^C
 chris@retina:~$ 
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    xev failed to show me Mx Anywhere 2 mouse buttons, this method displayed correct button.
    – user351764
    Commented Jul 9, 2017 at 13:43
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There is the xev program for graphic mode - see the man page of xev.

On Ubuntu/Debian it is packed into the x11-utils package.

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  • Using this at the command line and pushing the key that I thought wasn't working, made the key start working. Wild, I'll take it! Commented Nov 7, 2019 at 22:28
  • Add it displays timing information (in contrast to showkey). Commented Jan 15, 2020 at 8:41
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The better command that I know for this functionality is showkey, with parameter -a.

You could try, and Ctrl + D to exit:

showkey -a
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    showkey is already mentioned in the earlier answers. Commented May 30, 2015 at 18:55
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    But the addition -a is useful, showing how to use the command. But should be a comment then. Commented Sep 26, 2015 at 7:59
  • sudo showkey -a works with ssh too. Commented Oct 17, 2017 at 8:50
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    Can you add to your answer why "-a" is better? Thanks in advance. Commented Jan 12, 2020 at 22:22
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    Without the -a option I was getting the error: Couldn't get a file descriptor referring to the console when using this over ah SSH connection.
    – awatts
    Commented Jan 14, 2021 at 11:19
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If you are looking for something that graphically shows you what key is pressed currently (perhaps for the corner of a screencast), key-mon might be the ticket.

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  • If you can find the increasingly difficult-to-find Python 2.x and PyGTK (GTK+ 2.x) dependencies, I'd recommend key-mon as the nicest-looking option for screencasts. (I'd try my hand at porting to Python 3.x and GTK+ 3.x, but I have too much else on my plate that's more urgently needed.)
    – ssokolow
    Commented Jan 25, 2020 at 8:43
  • key-mon is pretty cumbersome to install unfortunately, code hasn't been updated/maintained in over 8 years and dependencies aren't easy to find as @ssokolow mentioned. The only alternative is screenkey which is also a bit weird but does work.
    – SidOfc
    Commented May 21, 2020 at 13:42
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You can also use evtest. In some situations, it is better than xev as it shows keys even when a key is already captured.

To install under Ubuntu/Linux Mint, do

sudo apt-get install evtest

to run sudo evtest and pick a device number.

Example output:

$ sudo evtest
No device specified, trying to scan all of /dev/input/event*
Available devices:
/dev/input/event0:    Lid Switch
/dev/input/event1:    Power Button
/dev/input/event2:    Power Button
/dev/input/event3:    AT Translated Set 2 keyboard
/dev/input/event4:    ETPS/2 Elantech Touchpad
/dev/input/event5:    Logitech Logitech G930 Headset
/dev/input/event6:    Video Bus
/dev/input/event7:    HDA Intel HDMI HDMI/DP,pcm=8
/dev/input/event8:    HDA Intel HDMI HDMI/DP,pcm=7
/dev/input/event9:    HDA Intel HDMI HDMI/DP,pcm=3
/dev/input/event10:    HDA Intel PCH Headphone
/dev/input/event11:    HDA Intel PCH Mic
/dev/input/event12:    WebCam SC-10HDP12B24N
/dev/input/event13:    ELAN Touchscreen
Select the device event number [0-13]: 5
Input driver version is 1.0.1
Input device ID: bus 0x3 vendor 0x46d product 0xa1f version 0x101
Input device name: "Logitech Logitech G930 Headset"
Supported events:
  Event type 0 (EV_SYN)
  Event type 1 (EV_KEY)
    Event code 114 (KEY_VOLUMEDOWN)
    Event code 115 (KEY_VOLUMEUP)
    Event code 163 (KEY_NEXTSONG)
    Event code 164 (KEY_PLAYPAUSE)
    Event code 165 (KEY_PREVIOUSSONG)
    Event code 256 (BTN_0)
    Event code 257 (BTN_1)
    Event code 258 (BTN_2)
    Event code 259 (BTN_3)
    Event code 260 (BTN_4)
    Event code 261 (BTN_5)
    Event code 262 (BTN_6)
    Event code 263 (BTN_7)
    Event code 264 (BTN_8)
    Event code 265 (BTN_9)
  Event type 4 (EV_MSC)
    Event code 4 (MSC_SCAN)
Properties:
Testing ... (interrupt to exit)
Event: time 1412585327.807585, type 4 (EV_MSC), code 4 (MSC_SCAN), value c00b5
Event: time 1412585327.807585, type 1 (EV_KEY), code 163 (KEY_NEXTSONG), value 1
Event: time 1412585327.807585, -------------- SYN_REPORT ------------
Event: time 1412585327.927557, type 4 (EV_MSC), code 4 (MSC_SCAN), value c00b5
Event: time 1412585327.927557, type 1 (EV_KEY), code 163 (KEY_NEXTSONG), value 0
Event: time 1412585327.927557, -------------- SYN_REPORT ------------
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    Doesn't work with SSH. Looks like there is no /dev/input at all there. Commented Nov 8, 2015 at 11:26
13

If you're at a shell prompt, you can press Ctrl-v then the key of interest to see what the output is. For example, on my system, pressing Ctrl-v then Right Arrow shows ^[[C which means Escape, Left Bracket, C.

As others have mentioned, xev is the way to go for X11.

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  • But "^[[C" is not a key. A terminal escape sequence, rather, maybe? Commented Jan 12, 2020 at 22:18
  • Indeed. It's Esc+[C. showkey -a would also show escape sequence for a pressed special key + codes for each element of an escape sequence. Commented Jun 27, 2020 at 20:22
  • Yes, it's an escape sequence that pressing Right Arrow produces on my system at the shell prompt in the terminal I'm using. Commented Jun 28, 2022 at 18:57
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You'd be wanting xev.

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xev | grep 'keycode'
    state 0x0, keycode 36 (keysym 0xff0d, Return), same_screen YES,
    state 0x0, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
    state 0x4, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
    state 0x0, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
    state 0x4, keycode 52 (keysym 0x7a, z), same_screen YES,
    state 0x4, keycode 37 (keysym 0xffe3, Control_L), same_screen YES,
    state 0x0, keycode 54 (keysym 0x63, c), same_screen YES,
    state 0x0, keycode 52 (keysym 0x7a, z), same_screen YES,
    state 0x0, keycode 54 (keysym 0x63, c), same_screen YES,
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    xev -event keyboard reports only keyboard events. Commented Oct 17, 2017 at 8:51
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If you only want to see a human-friendly-ish output of the key pressed, you can use this:

xev | sed -n 's/[ ]*state.* \([^ ]*\)).*/\1/p'

Note you'll get the keypress output on both keydown and keyup.

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