kleur

The fastest Node.js library for formatting terminal text with ANSI colors~!

Features

No dependencies
Super &
Supports & colors
No String.prototype modifications
Conditional
Familiar

As of v3.0 the Chalk-style syntax (magical getter) is no longer used. If you need or require that syntax, consider using , which maintains chalk parity.

Install

$ npm install --save kleur

Usage

const { red, white, blue, bold } = require('kleur');

// basic usage
red('red text');

// chained methods
blue().bold().underline('howdy partner');

// nested methods
bold(`${ white().bgRed('[ERROR]') } ${ red().italic('Something happened')}`);

Chained Methods

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

Nested Methods

const { yellow, red, cyan } = require('kleur');

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

Conditional Support

Toggle color support as needed; kleur includes simple auto-detection which may not cover all cases.

const kleur = require('kleur');

// manually disable
kleur.enabled = false;

// or use another library to detect support
kleur.enabled = require('color-support').level;

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

API

Any kleur method returns a String when invoked with input; otherwise chaining is expected.

It's up to the developer to pass the output to destinations like console.log, process.stdout.write, etc.

Colors:

black — red — green — yellow — blue — magenta — cyan — white — gray — grey

Backgrounds:

bgBlack — bgRed — bgGreen — bgYellow — bgBlue — bgMagenta — bgCyan — bgWhite

Modifiers:

reset — bold — dim — italic* — underline — inverse — hidden — strikethrough*

* Not widely supported

Benchmarks

Using Node v10.13.0

Load time

chalk       :: 14.543ms
kleur       ::  0.474ms
ansi-colors ::  1.923ms

Performance

# All Colors
  ansi-colors  x 199,381 ops/sec ±1.04% (96 runs sampled)
  chalk        x  12,107 ops/sec ±2.07% (87 runs sampled)
  kleur        x 715,334 ops/sec ±0.30% (93 runs sampled)

# Stacked colors
  ansi-colors  x 24,494 ops/sec ±1.03% (93 runs sampled)
  chalk        x  2,650 ops/sec ±2.06% (85 runs sampled)
  kleur        x 75,798 ops/sec ±0.19% (97 runs sampled)

# Nested colors
  ansi-colors  x  77,766 ops/sec ±0.32% (94 runs sampled)
  chalk        x   5,596 ops/sec ±1.85% (86 runs sampled)
  kleur        x 137,660 ops/sec ±0.31% (93 runs sampled)

Credits

Beginning with kleur@3.0, the Chalk-style syntax (magical getter) has been replaced with function calls per key:

// Old:
c.red.bold.underline('old');

// New:
c.red().bold().underline('new');

As I work more with Rust, the newer syntax feels so much better & more natural!

If you prefer the old syntax, you may migrate to ansi-colors. Versions below kleur@3.0 have been deprecated.

License

Previouskind-of NextLast Call Webpack Plugin

Last updated 3 years ago

Was this helpful?

const { red, white, blue, bold } = require('kleur'); // basic usage red('red text'); // chained methods blue().bold().underline('howdy partner'); // nested methods bold(`${ white().bgRed('[ERROR]') } ${ red().italic('Something happened')}`);

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

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

const kleur = require('kleur'); // manually disable kleur.enabled = false; // or use another library to detect support kleur.enabled = require('color-support').level; console.log(kleur.red('I will only be colored red if the terminal supports colors'));

# All Colors ansi-colors x 199,381 ops/sec ±1.04% (96 runs sampled) chalk x 12,107 ops/sec ±2.07% (87 runs sampled) kleur x 715,334 ops/sec ±0.30% (93 runs sampled) # Stacked colors ansi-colors x 24,494 ops/sec ±1.03% (93 runs sampled) chalk x 2,650 ops/sec ±2.06% (85 runs sampled) kleur x 75,798 ops/sec ±0.19% (97 runs sampled) # Nested colors ansi-colors x 77,766 ops/sec ±0.32% (94 runs sampled) chalk x 5,596 ops/sec ±1.85% (86 runs sampled) kleur x 137,660 ops/sec ±0.31% (93 runs sampled)