Originally created by a designer and a developer at Twitter, Bootstrap has become one of the most popular front-end frameworks and open source projects in the world.

Bootstrap was created at Twitter in mid-2010 by @mdo and @fat. Prior to being an open-sourced framework, Bootstrap was known as Twitter Blueprint. A few months into development, Twitter held its first Hack Week and the project exploded as developers of all skill levels jumped in without any external guidance. It served as the style guide for internal tools development at the company for over a year before its public release, and continues to do so today.

Originally released on , we’ve since had over twenty releases, including two major rewrites with v2 and v3. With Bootstrap 2, we added responsive functionality to the entire framework as an optional stylesheet. Building on that with Bootstrap 3, we rewrote the library once more to make it responsive by default with a mobile first approach.


Bootstrap is maintained by the founding team and a small group of invaluable core contributors, with the massive support and involvement of our community.

Core team

Get involved with Bootstrap development by opening an issue or submitting a pull request. Read our contributing guidelines for information on how we develop.

Sass team

The official Sass port of Bootstrap was created and is maintained by this team. It became part of Bootstrap’s organization with v3.1.0. Read the Sass contributing guidelines for information on how the Sass port is developed.

Brand guidelines

Have a need for Bootstrap’s brand resources? Great! We have only a few guidelines we follow, and in turn ask you to follow as well. These guidelines were inspired by MailChimp’s Brand Assets.

Mark and logo

Use either the Bootstrap mark (a capital B) or the standard logo (just Bootstrap). It should always appear in Helvetica Neue Bold. Do not use the Twitter bird in association with Bootstrap.





The project and framework should always be referred to as Bootstrap. No Twitter before it, no capital s, and no abbreviations except for one, a capital B.



Twitter Bootstrap


Our docs and branding use a handful of primary colors to differentiate what is Bootstrap from what is in Bootstrap. In other words, if it’s purple, it’s representative of Bootstrap.