NO_COLOR

Last updated: 2026-02-09

An increasing number of command-line software programs output text withANSI colorescape codes by default.While some developers and users obviously prefer seeing these colors,some users don’t.Unfortunately, every new piece of software seems to have adifferent wayof disabling colored text output and some software has no way at all.

Accepting the futility of trying to reverse this trend, an informal standardwas proposed in 2017:

Command-line software which adds ANSI color to its output by default shouldcheck for aNO_COLOR environment variable that, when present and not an emptystring (regardless of its value), prevents the addition of ANSI color.

By adopting this standard, users that prefer to have plain, non-colored textoutput can exportNO_COLOR=1 to their shell’s environment and automaticallydisable color by default in all supported software.

If your software outputs color by default, please consider not doing so.If you insist, please implement this standard to make it easy for yourusers to disable color and then add your software to this list bysubmitting a pull request.

If your software does not output color by default, you do not need to botherwith this standard.

Example Implementation

#include <stdbool.h>#include <stdio.h>#include <stdlib.h>intmain(int argc, char *argv[]){char *no_color = getenv("NO_COLOR");bool color = true;if (no_color != NULL && no_color[0] != '\0')color = false;/* do getopt(3) and/or config-file parsing to possibly turn color back on */...}

Frequently Asked Questions

1. Why not just set$TERM todumb orxterm without color support?Or change all color definitions in the terminal to print the same color?

   The terminal is capable of color and should be able to print color when instructed.NO_COLOR is a hint to the software running in the terminal to suppress addition of color, not to the terminal to prevent any color from being shown.

   It is reasonable to configure certain software such as a text editor to use color or other ANSI attributes sparingly (such as the reverse attribute for a status bar) while still desiring that other software not add color unless configured to. It should be up to the user whether color is used, not the software author.

2. How should configuration files and command-line arguments be processedin the presence ofNO_COLOR?

   User-level configuration files and per-instance command-line arguments should override theNO_COLOR environment variable. A user should be able to exportNO_COLOR=1 in their shell configuration file as a default, but configure a specific program in its configuration file to specifically enable color.

   This also means that software thatcan add color but doesn’t by default does not need to care aboutNO_COLOR, because it will only ever be adding color when instructed to do so (as it should be).

3. Should the presence ofNO_COLOR disable other styling such as bold,underline, and italic?

   No. This standard only signals the user’s intention regarding adding ANSI color to text output.

Color libraries supportingNO_COLOR to disable default color output

Software using these libraries to output color inherently support disablingcolor by default viaNO_COLOR.

Software directly supportingNO_COLOR to disable color output by default

Disabling color in software not supportingNO_COLOR