head to head · open source
Open WebUI vs Fullmoon
Open WebUI has 152,394 GitHub stars, 22,296 forks, 294 open issues and last shipped yesterday. Fullmoon has 2,266 stars, 220 forks, 45 open issues and last shipped 1.4 years ago. Open WebUI leads on adoption by 6,625% (152,394 vs 2,266 stars). Open WebUI is written in Python under a custom or non-standard licence; Fullmoon is written in Swift under MIT. Open WebUI has attracted 15% as many forks as stars, Fullmoon 10%. Open WebUI was the more recently maintained of the two, and both are self-hostable with no licence fee.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| Open WebUI | Fullmoon | |
|---|---|---|
| GitHub stars | ★ 152K | ★ 2.3K |
| License | Custom / other | MIT |
| Written in | Python | Swift |
| Last push | 2026-09-17 | 2025-05-05 |
| Forks | ⑂ 22K | ⑂ 220 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Open WebUI if
- You weight community size — 152K stars and counting
- You want the Custom / other license terms
- Your stack matches Python
- You value the larger contributor base for long-term maintenance
pick Fullmoon if
- You want the Fullmoon feature set and don't need the biggest community
- You prefer the MIT license terms
- Your stack matches Swift
- You evaluated both and Fullmoon fits your workflow better
About Open WebUI
Open WebUI is a self hosted, open source AI interface that unifies access to local and cloud based large language models. It runs entirely in a web browser and supports Ollama for local model hosting alongside any OpenAI compatible API, including services like LMStudio, GroqCloud, Mistral, and OpenRouter. Built in Python, it functions as a drop in replacement for proprietary AI platforms, giving users full control over their model infrastructure and data.
read the full Open WebUI overview →
About Fullmoon
Fullmoon is an iOS application for chatting with local large language models, built in Swift and released under the MIT license. It is optimized for Apple silicon and runs across iPhone, iPad, and Mac, with chat history stored locally on the device and a customizable interface. The project lives in the Apple ecosystem and depends on MLX Swift, Apple's array framework for machine learning research on Apple silicon.
read the full Fullmoon overview →
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Frequently asked questions
Is Open WebUI or Fullmoon more popular?
Open WebUI has 152,394 GitHub stars and Fullmoon has 2,266. Open WebUI has the larger community by that measure.
Are Open WebUI and Fullmoon free?
Both are open source. Open WebUI has no licence declared in this registry, and Fullmoon is licensed under MIT. Both are free to self-host.
What is the difference between Open WebUI and Fullmoon?
Open WebUI is written in Python and Fullmoon in Swift. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, Open WebUI or Fullmoon?
Choose Open WebUI if you want the larger community (152,394 stars) or its Custom / other licence terms. Choose Fullmoon if its feature set, stack or MIT licence fits better. Both are self-hostable.