The deciding difference is operational: LiteLLM can run on infrastructure you control, OpenRouter cannot. If that constraint is real for you, it settles the choice before anything else is considered.
One API key, several hundred models, automatic failover.
Self-hosted proxy that speaks one API to 100+ providers, with keys and budgets.
Give every agent its own virtual key so you can attribute and cap spend per surface.
| OpenRouter | LiteLLM | |
|---|---|---|
| Licence | Proprietary | Open source |
| Pricing | usage based | open source |
| Self-hostable | No | Yes |
| Languages | TypeScript, Python | Python, TypeScript |
| Install | — | pip install 'litellm[proxy]' |
| Keys required | OPENROUTER_API_KEY | None |
The deciding difference is operational: LiteLLM can run on infrastructure you control, OpenRouter cannot. If that constraint is real for you, it settles the choice before anything else is considered. OpenRouter: One API key, several hundred models, automatic failover. LiteLLM: Self-hosted proxy that speaks one API to 100+ providers, with keys and budgets.
OpenRouter is a hosted service only. LiteLLM can run on your own infrastructure.
OpenRouter is proprietary (usage based). LiteLLM is open source (open source).
Every page here answers to Accept: text/markdown and returns the same content at roughly a tenth the tokens. No separate site, no toggle — same URL.
curl -s -H "Accept: text/markdown" https://newagent.build/compare/openrouter-vs-litellm