ansi-colors

What is ansi-colors?

The ansi-colors npm package is a utility for styling strings in the terminal with ANSI escape codes. It allows developers to add color and style to text output in command-line applications.

What are ansi-colors's main functionalities?

Text Colors

Apply text color to strings. The example shows how to make text red.

"const colors = require('ansi-colors');\nconsole.log(colors.red('This is red text'));"

Background Colors

Apply background color to strings. The example shows how to give text a red background.

"const colors = require('ansi-colors');\nconsole.log(colors.bgRed('This has a red background'));"

Text Styles

Apply text styles like bold, italic, underline, etc. The example shows how to make text bold.

"const colors = require('ansi-colors');\nconsole.log(colors.bold('This is bold text'));"

Chaining Styles

Chain multiple styles together. The example shows text that is blue, bold, and underlined.

"const colors = require('ansi-colors');\nconsole.log(colors.blue.bold.underline('This is blue, bold, and underlined'));"

Custom Themes

Create custom themes by combining styles. The example defines a custom theme with styles for error and warning messages.

"const colors = require('ansi-colors');\nconst customTheme = {\n  error: colors.red.bold,\n  warning: colors.yellow.italic\n};\nconsole.log(customTheme.error('Error message'));\nconsole.log(customTheme.warning('Warning message'));"

Other packages similar to ansi-colors

chalk

Chalk is a popular package similar to ansi-colors that provides a chainable API for styling strings. It offers a more extensive API and additional features like template literal support.

kleur

Kleur is a lightweight alternative to ansi-colors, focusing on performance. It has a similar API but does not support older versions of Node.js.

colorette

Colorette is another lightweight package for coloring terminal text. It aims to be fast and simple, with a minimalistic API compared to ansi-colors.

README

ansi-colors

Easily add ANSI colors to your text and symbols in the terminal. A faster drop-in replacement for chalk, kleur and turbocolor (without the dependencies and rendering bugs).

Please consider following this project's author, Brian Woodward, and consider starring the project to show your :heart: and support.

Install

Install with npm:

$ npm install --save ansi-colors

Why use this?

ansi-colors is the fastest Node.js library for terminal styling. A more performant drop-in replacement for chalk, with no dependencies.

• Blazing fast - Fastest terminal styling library in node.js, 10-20x faster than chalk!

• Drop-in replacement for chalk.

• No dependencies (Chalk has 7 dependencies in its tree!)

• Safe - Does not modify the String.prototype like colors.

• Supports nested colors, and does not have the nested styling bug that is present in colorette, chalk, and kleur.

• Supports chained colors.

• Toggle color support on or off.

Usage

const c = require('ansi-colors');

console.log(c.red('This is a red string!'));
console.log(c.green('This is a red string!'));
console.log(c.cyan('This is a cyan string!'));
console.log(c.yellow('This is a yellow string!'));

Chained colors

console.log(c.bold.red('this is a bold red message'));
console.log(c.bold.yellow.italic('this is a bold yellow italicized message'));
console.log(c.green.bold.underline('this is a bold green underlined message'));

Nested colors

console.log(c.yellow(`foo ${c.red.bold('red')} bar ${c.cyan('cyan')} baz`));

Nested styling bug

ansi-colors does not have the nested styling bug found in colorette, chalk, and kleur.

const { bold, red } = require('ansi-styles');
console.log(bold(`foo ${red.dim('bar')} baz`));

const colorette = require('colorette');
console.log(colorette.bold(`foo ${colorette.red(colorette.dim('bar'))} baz`));

const kleur = require('kleur');
console.log(kleur.bold(`foo ${kleur.red.dim('bar')} baz`));

const chalk = require('chalk');
console.log(chalk.bold(`foo ${chalk.red.dim('bar')} baz`));

Results in the following

(sans icons and labels)

Toggle color support

Easily enable/disable colors.

const c = require('ansi-colors');

// disable colors manually
c.enabled = false;

// or use a library to automatically detect support
c.enabled = require('color-support').hasBasic;

console.log(c.red('I will only be colored red if the terminal supports colors'));

Strip ANSI codes

Use the .unstyle method to strip ANSI codes from a string.

console.log(c.unstyle(c.blue.bold('foo bar baz')));
//=> 'foo bar baz'

Available styles

Note that bright and bright-background colors are not always supported.

Colors	Background Colors	Bright Colors	Bright Background Colors
black	bgBlack	blackBright	bgBlackBright
red	bgRed	redBright	bgRedBright
green	bgGreen	greenBright	bgGreenBright
yellow	bgYellow	yellowBright	bgYellowBright
blue	bgBlue	blueBright	bgBlueBright
magenta	bgMagenta	magentaBright	bgMagentaBright
cyan	bgCyan	cyanBright	bgCyanBright
white	bgWhite	whiteBright	bgWhiteBright
gray
grey

(gray is the U.S. spelling, grey is more commonly used in the Canada and U.K.)

Style modifiers

• dim

• bold

• hidden

• italic

• underline

• inverse

• strikethrough

• reset

Aliases

Create custom aliases for styles.

const colors = require('ansi-colors');

colors.alias('primary', colors.yellow);
colors.alias('secondary', colors.bold);

console.log(colors.primary.secondary('Foo'));

Themes

A theme is an object of custom aliases.

const colors = require('ansi-colors');

colors.theme({
  danger: colors.red,
  dark: colors.dim.gray,
  disabled: colors.gray,
  em: colors.italic,
  heading: colors.bold.underline,
  info: colors.cyan,
  muted: colors.dim,
  primary: colors.blue,
  strong: colors.bold,
  success: colors.green,
  underline: colors.underline,
  warning: colors.yellow
});

// Now, we can use our custom styles alongside the built-in styles!
console.log(colors.danger.strong.em('Error!'));
console.log(colors.warning('Heads up!'));
console.log(colors.info('Did you know...'));
console.log(colors.success.bold('It worked!'));

Performance

Libraries tested

• ansi-colors v3.0.4
• chalk v2.4.1

Mac

MacBook Pro, Intel Core i7, 2.3 GHz, 16 GB.

Load time

Time it takes to load the first time require() is called:

• ansi-colors - 1.915ms
• chalk - 12.437ms

Benchmarks

# All Colors
  ansi-colors x 173,851 ops/sec ±0.42% (91 runs sampled)
  chalk x 9,944 ops/sec ±2.53% (81 runs sampled)))

# Chained colors
  ansi-colors x 20,791 ops/sec ±0.60% (88 runs sampled)
  chalk x 2,111 ops/sec ±2.34% (83 runs sampled)

# Nested colors
  ansi-colors x 59,304 ops/sec ±0.98% (92 runs sampled)
  chalk x 4,590 ops/sec ±2.08% (82 runs sampled)

Windows

Windows 10, Intel Core i7-7700k CPU @ 4.2 GHz, 32 GB

Load time

Time it takes to load the first time require() is called:

• ansi-colors - 1.494ms
• chalk - 11.523ms

Benchmarks

# All Colors
  ansi-colors x 193,088 ops/sec ±0.51% (95 runs sampled))
  chalk x 9,612 ops/sec ±3.31% (77 runs sampled)))

# Chained colors
  ansi-colors x 26,093 ops/sec ±1.13% (94 runs sampled)
  chalk x 2,267 ops/sec ±2.88% (80 runs sampled))

# Nested colors
  ansi-colors x 67,747 ops/sec ±0.49% (93 runs sampled)
  chalk x 4,446 ops/sec ±3.01% (82 runs sampled))

About

Contributing

Pull requests and stars are always welcome. For bugs and feature requests, please create an issue.

Running Tests

Running and reviewing unit tests is a great way to get familiarized with a library and its API. You can install dependencies and run tests with the following command:

$ npm install && npm test

Building docs

(This project's readme.md is generated by verb, please don't edit the readme directly. Any changes to the readme must be made in the .verb.md readme template.)

To generate the readme, run the following command:

$ npm install -g verbose/verb#dev verb-generate-readme && verb

Related projects

You might also be interested in these projects:

• ansi-wrap: Create ansi colors by passing the open and close codes. | homepage
• strip-color: Strip ANSI color codes from a string. No dependencies. | homepage

Contributors

Commits	Contributor
48	jonschlinkert
42	doowb
6	lukeed
2	Silic0nS0ldier
1	dwieeb
1	jorgebucaran
1	madhavarshney
1	chapterjason

Author

Brian Woodward

• GitHub Profile
• Twitter Profile
• LinkedIn Profile

License

Copyright © 2019, Brian Woodward. Released under the MIT License.

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This file was generated by verb-generate-readme, v0.8.0, on July 01, 2019.