CopilotKit vs OpenUI
Which should you use? A side-by-side look at what each one does, who it suits, what it costs, how hard it is to set up, and where each falls short.
Open source · MIT
A TypeScript toolkit for building chat and generative UI on top of AI agents in web, mobile, and chat apps.
Open source · MIT
Open standard and toolkit for AI models to generate and stream live user interfaces.
The short answer
Choose CopilotKit if you need…
- Developers adding an AI assistant or agent interface to a React or Next.js app
- Teams who want one agent backend to serve a web app, a mobile app, and Slack or Teams
- Projects that need agents to ask users for confirmation or edits before continuing
- Developers building chat interfaces that render custom UI components from tool calls
Choose OpenUI if you need…
- Developers adding AI-generated charts, forms, or tables to a web app
- Teams building chat assistants or copilots that answer with interactive UI
- React developers who want prebuilt chat layouts and component libraries
- Developers using LangChain or LangGraph agents that stream through AG-UI
Side-by-side
| CopilotKit | OpenUI | |
|---|---|---|
| Type | Library | Framework |
| Price | Free and open source | Free and open source |
| Licence | MIT | MIT |
| GitHub stars | 38.5k | 14.7k |
| Setup difficulty | Intermediate | Intermediate |
| How you get it | Install with a package manager | Install with a package manager |
| Main language | TypeScript | TypeScript |
| Last code update | 4 days ago | 4 days ago |
What each one is
CopilotKit
CopilotKit is an SDK for building applications where AI agents interact with users through a interface. It provides pieces such as a chat UI, shared state between agents and components, generative UI that agents can render at runtime, and human-in-the-loop prompts that pause an agent for user input. The README says the same agent can be served to React, Angular, Vue, React Native, and Slack or Microsoft Teams. The project is maintained by the company behind the AG-UI Protocol.
OpenUI
OpenUI is a framework for building interfaces that an AI model generates on the fly. It defines a compact language, OpenUI Lang, that a model streams as it writes, and a renderer that turns that stream into live UI in React, Vue, Svelte, or Angular. You define a set of components, and OpenUI builds the instructions that tell the model which components it may use.
Best for
CopilotKit
- Developers adding an AI assistant or agent interface to a React or Next.js app
- Teams who want one agent backend to serve a web app, a mobile app, and Slack or Teams
- Projects that need agents to ask users for confirmation or edits before continuing
- Developers building chat interfaces that render custom UI components from tool calls
OpenUI
- Developers adding AI-generated charts, forms, or tables to a web app
- Teams building chat assistants or copilots that answer with interactive UI
- React developers who want prebuilt chat layouts and component libraries
- Developers using LangChain or LangGraph agents that stream through AG-UI
Strengths
CopilotKit
- Covers several frontends (React, Angular, Vue, React Native) and chat channels from one agent backend, per the README
- Built on the AG-UI Protocol, which the README says is adopted by several large framework vendors
- Permissive MIT license with an active repository and a large star count
OpenUI
- MIT licensed and open source, with a published package set for several frontends
- Claims up to 67% fewer tokens than JSON for the same output (a figure from the README, not independently verified here)
- Streams output progressively, so the UI updates as the model writes
Not ideal for
CopilotKit
- Non-developers looking for a ready-made app; the README targets people writing code
- Projects that do not use JavaScript or TypeScript frontends, since the listed frameworks are JS-based
- Teams who want a fully self-contained product without integrating an agent framework of their own
OpenUI
- People who only need a plain chatbot with text replies, since the project is built around generated UI
- Teams not using a supported frontend (React, Vue, Svelte, Angular) without extra integration work
- Anyone who needs a fully proven production track record, since the README does not describe production deployments
Trade-offs
CopilotKit
- The README is partly a marketing overview; several features (Channels for Discord/WhatsApp, Vue quickstart) are listed as coming soon or only partly supported
- Some advanced features (rich threads, memories, analytics) belong to a separate hosted or self-hosted product called CopilotKit Intelligence, which may have its own plans
- Setup depends on your agent framework and frontend stack, so the learning curve is non-trivial
OpenUI
- The README is a broad overview; detailed API docs live on the external docs site
- Many packages and integrations make the right starting point unclear for newcomers
- Output quality depends on the model and on how well the component library is defined
Getting started
CopilotKit
Set up with your coding agent (run from your project root)
npx --yes copilotkit@latest onboard startInstall agent skills for your coding agent
npx copilotkit@latest skills installOpenUI
Scaffold a new chat app
npx @openuidev/cli@latest create --name genui-chat-appFrequently asked questions
What is the difference between CopilotKit and OpenUI?
CopilotKit: A TypeScript toolkit for building chat and generative UI on top of AI agents in web, mobile, and chat apps. OpenUI: Open standard and toolkit for AI models to generate and stream live user interfaces. CopilotKit suits developers adding an ai assistant or agent interface to a react or next.js app, while OpenUI suits developers adding ai-generated charts, forms, or tables to a web app.
Are CopilotKit and OpenUI free?
CopilotKit: Free and open source. OpenUI: Free and open source.
Is CopilotKit or OpenUI more popular?
CopilotKit has more GitHub stars (38.5k) than OpenUI (14.7k). Popularity isn't the same as fit — check which one matches your use case above.
What are other alternatives to CopilotKit and OpenUI?
Other options people compare them with include LangGraph, assistant-ui, Tambo, PageIndex, OpenAI Agents SDK.
Keep comparing
Built from our catalogue entries for both products: open-source details come from each project's README (AI-assisted, refreshed weekly) and GitHub data; AI-tool details are editorial. Spotted something wrong? Let us know from either product's page.