Reachat

Reachat is free and open source. It is a ReactJS UI library for building chat interfaces on top of large language models, so you are not hand-coding message lists, input boxes and rich content from scratch.

As a chat UI library for developers, Reachat aims at one job: getting a working LLM front end into your app quickly.

The components are highly customizable, which matters if your product has its own look and you do not want a generic chat widget.

Reachat supports rich media and multiple AI models, and it slots into an existing ReactJS project without a rebuild.

That cuts development time on the interface layer, the part most teams would rather not spend weeks on.

You need to be comfortable with ReactJS, since this is a library and not a no-code builder.

Connecting Reachat to a specific backend may take extra configuration, and the documentation may feel thin once you move into advanced use cases.

Expect to read some source code.

Because the price is zero, trying it on a prototype costs you only time.