OpenUI

Open Standard for Generative UI

OpenUI

Open Standard for Generative UI

Copied. Paste in your terminal to install.
Without
I need a hotel with a modern design in Paris
With OpenUI
I need a hotel with a modern design in Paris
Without
I need a hotel with a modern design in Paris
With OpenUI
I need a hotel with a modern design in Paris

Loved by 50,000+ developers from

OpenUI Open Source

Make your AI apps and agentsrespond with Interactive UI, Charts, Tables, Forms, Dashboards

Works with the tools you already use.

Works with any model, any frontend framework, and any design system or component library you already use.

  • Your model

    Closed or open, hosted or running on your own machine.

    OpenAI, Anthropic, Gemini, DeepSeek, xAI, Mistral, Qwen, Ollama

  • Your agents

    Add it to your existing agent code. No rewrite needed.

    Vercel AI SDK, LangChain, LangGraph, Convex, Cloudflare, CrewAI, n8n, Haystack

  • Your components

    Bring your own design system and component library.

    OpenUI Design system, shadcn/ui, Material UI, Ant Design, Radix UI, Chakra UI, Mantine, daisyUI

  • Your framework

    Works in the web framework you build with today.

    React, Next.js, Vue, Svelte, Angular, Nuxt, Remix, Astro

Faster answers,
fewer tokens.

3xfaster generation
67%fewer tokens

OpenUI Lang generates up to 3x faster and uses 67% fewer tokens than JSON-based UI formats. Fewer tokens means every generation finishes sooner and costs less.

OpenUI Gateway

OpenUI in production

Make agent responses more reliable in production. Gateway catches and repairs invalid output before users see it.

Keep your existing SDK

Chat Completions and Responses endpoints work with existing SDKs.

Repair before users see it

Fix invalid output as it streams, before it reaches users.

Stay online through outages

Gateway switches providers if one fails, keeping the same model.

Use existing LLM spend

Use your existing model provider credentials and commitments.

Trusted by thousands of developers

10,890 stars7M+ downloads across all packages

Frequently asked questions

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Join our Discord.

What should I use to build a Generative UI app?

Start with OpenUI and OpenUI Gateway. One command scaffolds a working app: npx @openuidev/cli@latest create.

Gateway gives you free models to build with, and repairs invalid output so broken UI doesn't reach users. The same setup carries into production.

How can I set up my coding agent to use OpenUI?

Run npx @openuidev/cli@latest setup-agent in your project. It adds OpenUI instructions to AGENTS.md, or creates the file, so Codex, Cursor, Claude Code, and other coding agents know how to build with OpenUI.

Run it again any time to refresh the instructions. Projects created with npx @openuidev/cli@latest create already include them.

What is OpenUI Lang?

OpenUI Lang is a compact, streaming-first language that LLMs write to build interfaces from your own components.

It is not JSON. Each line defines one component, such as root = Stack([header, chart]), so the interface renders while the response is still streaming.

Across the same 46 interfaces in our benchmark, OpenUI Lang averaged 1,362 output tokens per screen: 58% fewer than json-render and 52% fewer than A2UI, both JSON formats.

Is OpenUI only for chat?

No. OpenUI renders whatever interface a response describes: dashboards, forms, tables, charts, and complete application screens, not only messages in a chat thread.

The same response renders through React, Vue, Svelte, React Native, email, or a plain script tag.

Is OpenUI free and open source?

Yes. OpenUI is fully open source and works with your own components and design system.

Do I need both Gateway and Observability?

No. They work independently.

We recommend using both. Gateway makes generated UI more reliable. Observability shows what users experienced and whether it worked.

How is Thesys related to OpenUI?

Thesys is the company behind OpenUI, much like Vercel is the company behind Next.js.

Thesys maintains the open-source OpenUI framework and operates OpenUI Cloud.