TS 中文文档


Terminal string styling done right



Sindre Sorhus' open source work is supported by the community on GitHub Sponsors

Special thanks to:             Strapi is the leading open-source headless CMS.       It’s 100% JavaScript, fully customizable, and developer-first.    

Highlights


Expressive API
Highly performant
No dependencies
Ability to nest styles
256/Truecolor color support
Auto-detects color support
Doesn't extend String.prototype
Clean and focused
Actively maintained
Used by ~86,000 packages as of October 4, 2022

Install


  1. ``` shell
  2. npm install chalk
  3. ```

IMPORTANT:Chalk 5 is ESM. If you want to use Chalk with TypeScript or a build tool, you will probably want to use Chalk 4 for now. Read more.

Usage


  1. ``` js
  2. import chalk from 'chalk';

  4. console.log(chalk.blue('Hello world!'));
  5. ```

Chalk comes with an easy to use composable API where you just chain and nest the styles you want.

  1. ``` js
  2. import chalk from 'chalk';

  4. const log = console.log;

  6. // Combine styled and normal strings
  7. log(chalk.blue('Hello') + ' World' + chalk.red('!'));

  9. // Compose multiple styles using the chainable API
  10. log(chalk.blue.bgRed.bold('Hello world!'));

  12. // Pass in multiple arguments
  13. log(chalk.blue('Hello', 'World!', 'Foo', 'bar', 'biz', 'baz'));

  15. // Nest styles
  16. log(chalk.red('Hello', chalk.underline.bgBlue('world') + '!'));

  18. // Nest styles of the same type even (color, underline, background)
  19. log(chalk.green(
  20. 'I am a green line ' +
  21. chalk.blue.underline.bold('with a blue substring') +
  22. ' that becomes green again!'
  23. ));

  25. // ES2015 template literal
  26. log(`
  27. CPU: ${chalk.red('90%')}
  28. RAM: ${chalk.green('40%')}
  29. DISK: ${chalk.yellow('70%')}
  30. `);

  32. // Use RGB colors in terminal emulators that support it.
  33. log(chalk.rgb(123, 45, 67).underline('Underlined reddish color'));
  34. log(chalk.hex('#DEADED').bold('Bold gray!'));
  35. ```

Easily define your own themes:

  1. ``` js
  2. import chalk from 'chalk';

  4. const error = chalk.bold.red;
  5. const warning = chalk.hex('#FFA500'); // Orange color

  7. console.log(error('Error!'));
  8. console.log(warning('Warning!'));
  9. ```

Take advantage of console.log string substitution :

  1. ``` js
  2. import chalk from 'chalk';

  4. const name = 'Sindre';
  5. console.log(chalk.green('Hello %s'), name);
  6. //=> 'Hello Sindre'
  7. ```

API


chalk.<style>.<style>...


Example: chalk.red.bold.underline('Hello', 'world');

Chain styles and call the last one as a method with a string argument. Order doesn't matter, and later styles take precedent in case of a conflict. This simply means that chalk.red.yellow.green is equivalent to chalk.green.

Multiple arguments will be separated by space.

chalk.level


Specifies the level of color support.

Color support is automatically detected, but you can override it by setting the level property. You should however only do this in your own code as it applies globally to all Chalk consumers.

If you need to change this in a reusable module, create a new instance:

  1. ``` js
  2. import {Chalk} from 'chalk';

  4. const customChalk = new Chalk({level: 0});
  5. ```

Level Description
:--- :---
0 All colors disabled
1 Basic color support (16 colors)
2 256 color support
3 Truecolor support (16 million colors)

supportsColor


Detect whether the terminal supports color. Used internally and handled for you, but exposed for convenience.

Can be overridden by the user with the flags --color and --no-color. For situations where using --color is not possible, use the environment variable FORCE_COLOR=1 (level 1), FORCE_COLOR=2 (level 2), or FORCE_COLOR=3 (level 3) to forcefully enable color, or FORCE_COLOR=0 to forcefully disable. The use of FORCE_COLOR overrides all other color support checks.

Explicit 256/Truecolor mode can be enabled using the --color=256 and --color=16m flags, respectively.

chalkStderr and supportsColorStderr


chalkStderr contains a separate instance configured with color support detected for stderr stream instead of stdout. Override rules from supportsColor apply to this too. supportsColorStderr is exposed for convenience.

modifierNames, foregroundColorNames, backgroundColorNames, and colorNames


All supported style strings are exposed as an array of strings for convenience. colorNames is the combination of foregroundColorNames and backgroundColorNames.

This can be useful if you wrap Chalk and need to validate input:

  1. ``` js
  2. import {modifierNames, foregroundColorNames} from 'chalk';

  4. console.log(modifierNames.includes('bold'));
  5. //=> true

  7. console.log(foregroundColorNames.includes('pink'));
  8. //=> false
  9. ```

Styles


Modifiers


reset - Reset the current style.
bold - Make the text bold.
dim - Make the text have lower opacity.
italic - Make the text italic. (Not widely supported)
underline - Put a horizontal line below the text. (Not widely supported)
overline - Put a horizontal line above the text. (Not widely supported)
inverse - Invert background and foreground colors.
hidden - Print the text but make it invisible.
strikethrough - Puts a horizontal line through the center of the text. (Not widely supported)
visible - Print the text only when Chalk has a color level above zero. Can be useful for things that are purely cosmetic.

Colors


black
red
green
yellow
blue
magenta
cyan
white
blackBright (alias: gray, grey )
redBright
greenBright
yellowBright
blueBright
magentaBright
cyanBright
whiteBright

Background colors


bgBlack
bgRed
bgGreen
bgYellow
bgBlue
bgMagenta
bgCyan
bgWhite
bgBlackBright (alias: bgGray, bgGrey )
bgRedBright
bgGreenBright
bgYellowBright
bgBlueBright
bgMagentaBright
bgCyanBright
bgWhiteBright

256 and Truecolor color support


Chalk supports 256 colors and Truecolor (16 million colors) on supported terminal apps.

Colors are downsampled from 16 million RGB values to an ANSI color format that is supported by the terminal emulator (or by specifying {level: n} as a Chalk option). For example, Chalk configured to run at level 1 (basic color support) will downsample an RGB value of #FF0000 (red) to 31 (ANSI escape for red).

Examples:

chalk.hex('#DEADED').underline('Hello, world!')
chalk.rgb(15, 100, 204).inverse('Hello!')

Background versions of these models are prefixed with bg and the first level of the module capitalized (e.g. hex for foreground colors and bgHex for background colors).

chalk.bgHex('#DEADED').underline('Hello, world!')
chalk.bgRgb(15, 100, 204).inverse('Hello!')

The following color models can be used:

rgb - Example: chalk.rgb(255, 136, 0).bold('Orange!')
hex - Example: chalk.hex('#FF8800').bold('Orange!')
ansi256 - Example: chalk.bgAnsi256(194)('Honeydew, more or less')

Browser support


Since Chrome 69, ANSI escape codes are natively supported in the developer console.

Windows


If you're on Windows, do yourself a favor and use Windows Terminal instead of cmd.exe.

Origin story


colors.js used to be the most popular string styling module, but it has serious deficiencies like extending String.prototype which causes all kinds of problems and the package is unmaintained. Although there are other packages, they either do too much or not enough. Chalk is a clean and focused alternative.

Related


chalk-template - Tagged template literals support for this module
chalk-cli - CLI for this module
ansi-styles - ANSI escape codes for styling strings in the terminal
supports-color - Detect whether a terminal supports color
strip-ansi - Strip ANSI escape codes
strip-ansi-stream - Strip ANSI escape codes from a stream
has-ansi - Check if a string has ANSI escape codes
ansi-regex - Regular expression for matching ANSI escape codes
wrap-ansi - Wordwrap a string with ANSI escape codes
slice-ansi - Slice a string with ANSI escape codes
color-convert - Converts colors between different models
chalk-animation - Animate strings in the terminal
gradient-string - Apply color gradients to strings
chalk-pipe - Create chalk style schemes with simpler style strings
terminal-link - Create clickable links in the terminal

Maintainers


Sindre Sorhus
Josh Junon