21st
ActiveUI building blocks for the agentic internet
What it does
21st.dev is the largest React component registry for AI applications, used by 2M developers We provide the building blocks to create agent-powered apps: UI components, agent templates.
Its site says now · captured 2026-08-23
React Components, Templates & Themes — 12,000+ Crafted UI | 21st | 21st
12,000+ hand-crafted React and Tailwind CSS components, templates, and shadcn themes by real design engineers. Preview live, install with one command — for you and your AI agent.
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