7 releases (4 breaking)

0.5.1 Sep 7, 2021
0.5.0 Aug 17, 2021
0.4.0 Apr 9, 2018
0.3.1 Mar 31, 2018
0.1.0 Mar 19, 2018

#1349 in Command line utilities

38 downloads per month

MIT license


xcolor 🌈

Build Status Latest Version GitHub release dependency status License: MIT

Lightweight color picker for X11. Use mouse to select colors visible anywhere on the screen to get their RGB representation.


Using Cargo

xcolor can be installed using cargo:

cargo install xcolor

Building and running xcolor requires xcb and Xlib libraries to be present.

To get the latest development version of xcolor, you can direct cargo to install from the git repository:

cargo install --git 'https://github.com/Soft/xcolor.git'

Installing xcolor with cargo will not install its manual page or desktop file. To also install these additional files, invoke make install in the project directory. By default, the install script will place the files under /usr/local/ hierarchy.

Arch Linux

xcolor is available in the Arch User Repository. To install xcolor from AUR:

git clone https://aur.archlinux.org/xcolor.git
cd xcolor
makepkg -isr


Simply invoke the xcolor command to select a color. The selected color will be printed to the standard output.

xcolor 0.5.0
Samuel Laurén <samuel.lauren@iki.fi>:Callum Osmotherly <acheronfail@gmail.com>
Lightweight color picker for X11

    xcolor [OPTIONS]

    -h, --help       Prints help information
    -V, --version    Prints version information

    -c, --custom <FORMAT>                Custom output format
    -f, --format <NAME>                  Output format (defaults to hex) [possible values: hex, HEX, hex!, HEX!, plain,
    -P, --preview-size <PREVIEW_SIZE>    Size of preview, must be odd (defaults to 255)
    -S, --scale <SCALE>                  Scale of magnification (defaults to 8)
    -s, --selection <SELECTION>          Output to selection (defaults to clipboard) [possible values: primary,
                                         secondary, clipboard]

Saving to Selection

By default, the selected color is printed to the standard output. By specifying the -s flag, xcolor can be instructed to instead save the color to X11's selection. The selection to use can be specified as an argument. Possible selection values are clipboard (the default), primary, and secondary.

Because of the way selections work in X11, xcolor forks into background when -s mode is used. This behavior can be disabled by defining XCOLOR_FOREGROUND environment variable.

Color Preview

The -S or --scale flag controls the upscaling (or zoom) of the preview. By default it is set to 8 which indicates an 8x zoom level.

The -P or --preview-size flag controls the size of the preview in pixels. So that the preview always has a center pixel this number must be odd, if an even number is passed then it will be changed to the next odd number.


By default, the color values will be printed in lowercase hexadecimal format. The output format can be changed using the -f NAME switch. Supported format names are listed bellow:

Format Specifier Description Example Custom Format Equivalent
hex Lowercase hexadecimal (default) #ff00ff #%{02hr}%{02hg}%{02hb}
HEX Uppercase hexadecimal #00FF00 #%{02Hr}%{02Hg}%{02Hb}
hex! Compact lowercase hexadecimal1 #fff Not expressible
HEX! Compact uppercase hexadecimal1 #F0F Not expressible
rgb Decimal RGB rgb(255, 255, 255) rgb(%{r}, %{g}, %{b})
plain Decimal with semicolon separators 0;0;0 %{r};%{g};%{b}

1: The compact form refers to CSS three-letter color codes as specified by CSS Color Module Level 3. If the color is not expressible in three-letter form, the regular six-letter form will be used.

Custom Formats

The -f switch provides quick access to some commonly used formatting options. However, if custom output formatting is desired, this can be achieved using the -c FORMAT switch. The FORMAT parameter specifies a template for the output and supports a simple template language.

FORMAT templates can contain special expansions that are written inside %{...} blocks. These blocks will be expanded into color values according to the specifiers defined inside the block. Here are some examples of valid format strings and what they might translate to:

Format String Example Output
%{r}, %{g}, %{b} 255, 0, 100
Green: %{-4g} Green: ---7
#%{02hr}%{02hg}%{02hb} #00ff00
%{016Br} 0000000000000011

Expansion blocks in format strings always contain a channel specifier (r for red, g for green, and b for blue). Additionally, they can contain an optional number format specifier (h for lowercase hexadecimal, H for uppercase hexadecimal, o for octal, B for binary, and d for decimal) and an optional padding specifier consisting of a character to use for padding and the length the string should be padded to. We can use these rules to decode the above example string:

    | |||
    | ||`- Channel (red)
    | |`-- Number format specifier (binary)
    | `--- Padding length (16)
    `----- Character to use for padding (0)

In the output, we get the contents of the red color channel formatted in binary and padded with zeroes to be sixteen characters long.


Bugs & Issues should be reported at GitHub.


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