What it does Sub2API is a self-hosted API gateway that takes a single subscription to Claude, OpenAI, Gemini, or similar services and turns it into distributable API keys for multiple users. It handles authentication, token-level billing, rate limiting, and request forwarding so teams can share access without sharing credentials.

The interesting bit The project is essentially a commercial-grade quota-management layer built specifically for the “subscription sharing” use case — a problem most AI tools ignore. It even bakes in payments (Stripe, Alipay, WeChat Pay) so you can run it as a small business, not just an internal proxy.

Key highlights

• Supports OAuth and API-key upstream accounts with sticky-session routing
• Token-level usage tracking and per-user concurrency limits
• Built-in payment system for self-service top-ups; no separate billing service needed
• Admin dashboard with iframe embedding for external tools (ticketing, etc.)
• Docker-ready stack: Go backend, Vue 3 frontend, PostgreSQL, Redis

Caveats

• The README is heavy on sponsor listings and light on technical architecture or deployment complexity
• Demo credentials are public and shared, so treat the live demo as a UI preview, not a security model
• The project warns that third-party sites using the Sub2API name may be unaffiliated — verify what you’re actually deploying

Verdict Worth a look if you’re running an AI-tool reseller business or need to split expensive subscriptions across a team with actual billing. Overkill for a single developer who just wants to share one Claude key with a friend.