About Bootstrap
Bootstrap is a free and open-source CSS framework directed at responsive, mobile-first front-end web development. It contains CSS and JavaScript-based design templates for typography, forms, buttons, navigation, and other interface components.
How many people use Bootstrap
GitHub · npm- #1
Flutter179k - #2
Bootstrap175k - #3
shadcn/ui123k - #4
Ant Design99k - #5
MUI99k - #6Tailwind CSS97k
- #7
Storybook91k
#2 of 71 UI frameworks we have counts for (of 85) · bars are GitHub stars across these neighbours; the category leader is Flutter at 179k · as of September 7, 2026
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Bootstrap#2 of 71 UI frameworks
Flutter#1 of 71 UI frameworks
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Implied technologies
Detecting Bootstrap implies these are in the stack too - a report lists them alongside it.
How we audit Bootstrap
We measure the detected version against Bootstrap's release history and grade the surrounding stack with a Lighthouse-grade quality audit. Weak or outdated links weigh more - one risky dependency can pull the whole score down.
How the score worksMore technologies in UI frameworks
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Technology definitions from a community-maintained catalogue, licensed GPL-3.0. Attribution and source.