A toolkit providing simple and flexible HTML, CSS, and JS for popular UI components and interactions.
Ranked in these QuestionsQuestion Ranking
Pro Consistency across browsers
Pro Responsive design philosophy
Bootstrap is developed to be instantly compatible with all sizes of screens, so you don't have to worry about which device the user is accessing your site from. Yet if you prefer, you can disable responsiveness of Bootstrap.
Pro Well documented
Pro Designed to get a site running quickly
Bootstrap is designed to get a site up and running quickly. Each of it's components is pre-configured to help with getting a site up and running quickly.
Bootstrap can be customized in a variety of ways. Either by overriding the default CSS styles with new CSS styles or by editing the
.scss Bootstrap files.
Pro A wide variety of themes available
Pro Great community
Bootstrap is very popular and has a large community. As a result of this it is much easier to find help with anything you might need. This also gives you a treasure trove of prebuilt components to use and add to your site.
Pro One of the most popular ones
Ranked on GitHub as the most starred CSS repository.
Pro Supports responsive embeds
Allows easily adding responsiveness to
Pro Custom builds
Pro Great documentation
Con Large file size out of the box
Bootstrap has an out-of-the box filesize of ~276K, which is pretty large considering it's just CSS. Most of those styles aren't even used in 90% of web pages built with Bootstrap. By only including the required styles it can be trimmed by 70%-75%.
Con Websites can start to look the same
If the initial Bootstrap colors and styles are not changed or edited, different websites start looking the same even if they have nothing to do with each other and they are made by different developers.
Con Too many classes
Bootstrap's over-reliance on HTML classes for styling can get very messy very quickly. There's also an overabundance of DOM elements which have a lot of classes and are more often than not nested inside DOM elements with even more classes. This gets problematic down the line because the maintainability of the project gets harder when the project starts to get large.