Anthropic (Claude)
Overview
Open WebUI supports Anthropic's Claude models natively through their OpenAI-compatible endpoint. Just plug in your API key and start chatting — no middleware, no pipes, no extra setup required.
Open WebUI includes a built-in compatibility layer that automatically detects Anthropic URLs, handles model discovery, and translates requests. Chat completions, streaming, and tool calling all work correctly out of the box.
Anthropic states that their OpenAI-compatible API is intended for evaluation and testing, not production workloads. In practice, everything — including tool calling — works as intended, but be aware of this official stance. For full Claude-native features (PDF processing, citations, extended thinking, prompt caching), Anthropic recommends their native /v1/messages API, which can be accessed via a pipe function or a proxy like LiteLLM.
Step 1: Get Your API Key
- Go to console.anthropic.com.
- Create an account or sign in.
- Navigate to API Keys and generate a new key.
Step 2: Add the Connection in Open WebUI
- Open Open WebUI in your browser.
- Go to ⚙️ Admin Settings → Connections → OpenAI.
- Click ➕ Add Connection.
- Enter the following:
| Setting | Value |
|---|---|
| URL | https://api.anthropic.com/v1 |
| API Key | Your Anthropic API key |
- Click Save.
The URL field will suggest common provider endpoints as you type — just select the Anthropic URL from the dropdown.
Step 3: Start Chatting!
That's it! Open WebUI automatically detects the Anthropic endpoint and fetches available models. Select a Claude model from the model dropdown and you're good to go.
Streaming, multi-turn conversations, and tool calling all work seamlessly.
If you want only specific models to appear, you can add model IDs to the Model IDs (Filter) allowlist in the connection settings. Common model IDs:
| Model | ID |
|---|---|
| Claude Opus 4.6 | claude-opus-4-6 |
| Claude Sonnet 4.6 | claude-sonnet-4-6 |
| Claude Haiku 4.5 | claude-haiku-4-5 |
Check Anthropic's model documentation for the latest available model IDs.
Managing Your Connection
You can enable or disable your Anthropic connection at any time using the toggle switch next to the connection entry. This lets you temporarily deactivate a provider without deleting the connection or losing your configuration.
Learn More
- OpenAI-Compatible Providers — Protocol design philosophy and setup for other providers.
- Pipe Functions — Use Anthropic's native API with full feature support via a pipe function.