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Home/Categories/Web Development/21st.dev
icon of 21st.dev

21st.dev

Open source alternative to Tailwind UI, Vercel v0 and Supernova

  • 2.2K stars
  • MIT
  • Active this week
  • Last commit today

Last verified Oct 21, 2026

21st.dev is an open source community registry of production-ready React Tailwind UI components built on shadcn/ui conventions, installable via CLI. MIT licensed with no subscription required.

Visit websiteGitHub2.2K stars
image of 21st.dev
TL;DR

21st.dev is a community registry of React and Tailwind UI components built around shadcn-style copy-and-paste workflows. It replaces paid component marketplaces and private UI snippets for developers who want production-ready interface blocks without a subscription. MIT licensed repository.

Read the full breakdownHide the full breakdownWho it is for, how it works, trade-offs and the FAQ
who it's for

Who 21st.dev is for#

Frontend teams accelerating product UI

Use 21st.dev to find starting components for product screens without buying a paid UI kit or adding a locked package.

Skip if:

Your organization requires a single governed design system package with centralized versioning.

Founders building polished MVPs

Use 21st.dev when you need usable React UI blocks quickly and are comfortable adapting copied Tailwind code.

Skip if:

You need a no-code site builder or finished marketing template instead of application components.

the problem

The problem it solves#

Frontend teams lose time rebuilding common product UI: dashboards, forms, pricing pages, auth screens, and interaction patterns. Paid UI kits can speed this up, but they often hide code behind licenses, design-tool bundles, or subscription access.

The practical problem is ownership. Developers want components they can inspect, copy into the codebase, adapt to their design system, and keep without depending on a vendor package.

how 21st.dev solves it

How it solves it#

Copy-and-paste component registry

Provides UI components that developers can bring into their own React and Tailwind projects instead of installing a black-box component dependency.

shadcn-style workflow

Fits the familiar modern component pattern where source code lands in the app, so teams can edit styles, behavior, and accessibility details directly.

Community-sourced UI blocks

Collects interface blocks from a broader community, giving developers more starting points than a single internal snippet folder.

strengths · trade-offs

Strengths and trade-offs#

Strengths

  • Code ownership over package dependencyCopying components into the app lets teams adapt the implementation and avoid waiting on a third-party package for every visual or behavior change.
  • Good fit for Tailwind teamsThe registry targets React and Tailwind conventions, so it fits teams already using utility-first styling and app-owned component files.

Trade-offs

  • -You maintain copied codeOnce a component is copied into an app, updates, bug fixes, and accessibility reviews become the team's responsibility. That is the tradeoff for ownership.
tech stack · detected from GitHub

What it's built on#

Languages
JavaScriptTypeScript
Frameworks
Next.jsReactshadcn/uiTailwind CSS
frequently asked

FAQ#

What is 21st.dev?

21st.dev is a registry of React and Tailwind UI components for developers who want copy-and-paste component code.

Is 21st.dev a component library?

21st.dev behaves more like a component registry than a traditional package-only library. Developers copy component source into their apps and adapt it.

Who should use 21st.dev?

21st.dev fits React and Tailwind teams that want reusable UI starting points without paying for a proprietary component marketplace.

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