Share API access without sharing keys

Presign is an open-source service that generates secure, time-limited presigned URLs for any HTTP API. It lets you share API access with teammates, scripts, or applications without exposing your API keys. Keys are AES-256 encrypted at rest, and URLs use HMAC-SHA256 signatures.

You store your API key in Presign (encrypted with AES-256), then generate a presigned URL with specific permissions: allowed HTTP methods, URL path patterns, and an expiration time. The URL is signed with HMAC-SHA256 using your signing secret. When someone uses the URL, Presign verifies the signature and proxies the request to the API.

Yes. Presign offers a free tier with 3 API connections and 1,000 requests per month. No credit card required. Pro and Enterprise plans are available for teams needing more capacity.

Presign works with any HTTP API. The API Store includes preconfigured providers like OpenAI, Anthropic, Groq, and more. You can also add any custom API by providing its base URL.

Yes. API keys are encrypted with AES-256 at rest and never leave the server. Presigned URLs use HMAC-SHA256 signatures and can be restricted by HTTP method, path pattern, and expiration time. The service runs on Cloudflare Workers at the edge.

Unlike traditional API gateways, Presign focuses specifically on presigned URL generation. URLs are self-contained with their permissions encoded in the signature — no session state, no token refresh, no SDK required. Recipients just use a plain URL.