Recursively flatten an array or arrays. This is the fastest implementation of array flatten.
Switch branches/tags
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Failed to load latest commit information.
benchmark add libs to benchmarks Apr 14, 2017
.editorconfig run update, lint Apr 14, 2017
.eslintrc.json run `update` Jul 5, 2017
.gitattributes lint Mar 11, 2015
.gitignore run `update` Jul 5, 2017
.travis.yml run `update` Jul 5, 2017 add libs to benchmarks Apr 14, 2017
LICENSE run `update` Jul 5, 2017 run verb to generate readme Jul 5, 2017
appveyor.yml adds appveyor Apr 14, 2017
bower.json 1.0.3 Apr 17, 2017
index.js run `update` Jul 5, 2017
package.json 1.1.0 Jul 5, 2017
test.js run `update` Jul 5, 2017

arr-flatten NPM version NPM monthly downloads NPM total downloads Linux Build Status Windows Build Status

Recursively flatten an array or arrays.


Install with npm:

$ npm install --save arr-flatten


Install with bower

$ bower install arr-flatten --save


var flatten = require('arr-flatten');

flatten(['a', ['b', ['c']], 'd', ['e']]);
//=> ['a', 'b', 'c', 'd', 'e']

Why another flatten utility?

I wanted the fastest implementation I could find, with implementation choices that should work for 95% of use cases, but no cruft to cover the other 5%.


Related projects

  • arr-filter: Faster alternative to javascript's native filter method. | homepage
  • arr-union: Combines a list of arrays, returning a single array with unique values, using strict equality… more | homepage
  • array-each: Loop over each item in an array and call the given function on every element. | homepage
  • array-unique: Remove duplicate values from an array. Fastest ES5 implementation. | homepage


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


Commits Contributor
20 jonschlinkert
1 lukeed

Building docs

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

To generate the readme, run the following command:

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

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


Jon Schlinkert


Copyright © 2017, Jon Schlinkert. Released under the MIT License.

This file was generated by verb-generate-readme, v0.6.0, on July 05, 2017.