Print a 256-color test pattern in the terminal

Question

How do I print a 256-colour test pattern in my terminal?

I want to check that my terminal correctly supports 256 colours.

Solution 1

256-colour test pattern

For the above, you can use my bash code. ("Look Ma, no subprocesses!")

Or for a bash quicky:

for i in {0..255} ; do
    printf "\x1b[38;5;${i}m%3d " "${i}"
    if (( $i == 15 )) || (( $i > 15 )) && (( ($i-15) % 12 == 0 )); then
        echo;
    fi
done

---

24-bit / truecolour test pattern

See this question for the full spectrum :)

Solution 2

Install an application named colortest

and use the following commands to test the ASCII color graph

colortest-8   => Display color palette using 8 colors.
colortest-16  => Display color palette using 16 colors.
colortest-256 => Display color palette using 256 colors.

Comments

[lblasa]

Please do not crosspost (askubuntu.com/questions/821157/…).

[Tom Hale]

My understanding is that that is to prevent time being wasted answering a question already answered. It's entirely relevant to both sites... How to say which is more relevant?

[Emmanuel]

non Ubuntu related question should redirected here

[Tom Hale]

Yes - this is not limited to Ubuntu

[Julie Pelletier]

Not sure why you formatted it this way but at least it works and looks good.

[Tom Hale]

Suggestions for improvement?

[phg]

“Install an application named colortest”—this kind of begs the question. Where does that colortest package originate? It doesn’t appear to be in the Fedora or Arch repos.

[SHW]

Said application is available for ubuntu. For more info, refer this link vim.org/scripts/script.php?script_id=1349

[Emmanuel]

can try that one printf "%03d\e[48;5;${i}m \e[0m " $i;

[Tom Hale]

@Zach R I just did a quick google... What evidence do you have for you assertion it's not a built-in?

[Zach R]

``` $ bash -c 'which printf' /usr/bin/printf $ zsh -c 'which printf' printf: shell built-in command ```

[Zach R]

Apparently it is a builtin, per the Bash documentation. Bash just doesn't show builtins with "which". manpages.ubuntu.com/manpages/xenial/man7/bash-builtins.7.htm‌​l