Bootstrap is an open-source toolkit for developing with HTML, CSS, and JS. Quickly prototype your ideas or build your entire app with our Sass variables and mixins, responsive grid system, extensive prebuilt components, and powerful plugins built on jQuery.

Our latest release, Bootstrap 5, focuses on improving v4’s codebase with as few major breaking changes as possible. We improved existing features and components, removed support for older browsers, dropped jQuery for regular JavaScript, and embraced more future-friendly technologies like CSS custom properties as part of our tooling.