Open WebUI tech stack

Open WebUI is a self-hosted interface for local and cloud AI models. It runs on SvelteKit, FastAPI, SQLAlchemy, Socket.IO and 0 more, read from its public repo open-webui/open-webui.

A self-hosted AI chat interface with document retrieval, tools, and support for Ollama and OpenAI-compatible endpoints. Can run offline with local models; external model services incur their own costs. The reviewed license includes branding restrictions and enterprise terms are available.

AI · web · https://openwebui.com · 156,956 GitHub stars, Open WebUI License (branding restrictions) (2026-10-27)

Built with

Frontend

SvelteKit (package.json@33c1978d5bad: "@sveltejs/kit")

Backend

FastAPI (pyproject.toml@33c1978d5bad: fastapi==)
SQLAlchemy (pyproject.toml@33c1978d5bad: sqlalchemy)

Realtime

Socket.IO (pyproject.toml@33c1978d5bad: python-socketio)

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Open WebUI tech stack

Built with

Frontend

Backend

Realtime

What do I use to build this?And how much will it cost?What do you want to build?

What Are You Building?

Prices read from each vendor’s own pricing page

One placefor every stack decision.

Plan

Cost as you grow

Vendors

Audit

Billing

Showcase

Give your AI assistantaccess to Kong Reviews.

See what real productsare built on.

How services are ranked

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What's it built on?

What it runs on

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My Stacks

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Vendors

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Missing a Vendor?

Questions

Pick what works.Build what’s next.

What do I use to build this?
And how much will it cost?What do you want to build?

One place
for every stack decision.

Give your AI assistant
access to Kong Reviews.

See what real products
are built on.

Already built?
Start from what you run.

Pick what works.
Build what’s next.

Pick what works.
Build what’s next.