# Sign In with Farcaster (SIWF)

**Canonical:** https://apis.io/apis/farcaster/siwf/  
**Provider:** Farcaster — https://apis.io/providers/farcaster/  
**Base URL:** https://docs.farcaster.xyz/developers/siwf  
**Documentation:** https://docs.farcaster.xyz/developers/siwf

Sign In with Farcaster (SIWF) is one of 15 APIs that [Farcaster](https://apis.io/providers/farcaster/) publishes on the [APIs.io](https://apis.io/) network. Tagged areas include Authentication, SIWF, and Identity. The published artifact set on APIs.io includes API documentation.

Authentication flow that lets users sign in to third-party apps with their Farcaster identity, returning a verified FID and optional profile data. Backed by EIP-4361-style signed messages.

## Machine-readable artifacts (1)

- **Documentation** — https://docs.farcaster.xyz/developers/siwf

## Other Farcaster APIs (12)

- [Snapchain / Hub API](https://apis.io/apis/farcaster/snapchain/)
- [Farcaster Mini Apps SDK](https://apis.io/apis/farcaster/mini-apps-sdk/)
- [Farcaster AuthKit (React)](https://apis.io/apis/farcaster/auth-kit/)
- [Neynar Hosted Farcaster API](https://apis.io/apis/farcaster/neynar/)
- [Warpcast / Farcaster Client API](https://apis.io/apis/farcaster/warpcast-api/)
- [Farcaster Casts API](https://apis.io/apis/farcaster/farcaster-casts-api/)
- [Farcaster Events API](https://apis.io/apis/farcaster/farcaster-events-api/)
- [Farcaster Info API](https://apis.io/apis/farcaster/farcaster-info-api/)
- [Farcaster Links API](https://apis.io/apis/farcaster/farcaster-links-api/)
- [Farcaster OnChain API](https://apis.io/apis/farcaster/farcaster-onchain-api/)
- [Farcaster Reactions API](https://apis.io/apis/farcaster/farcaster-reactions-api/)
- [Farcaster Submit API](https://apis.io/apis/farcaster/farcaster-submit-api/)

## Tags

Authentication, SIWF, Identity

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/farcaster/siwf/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/farcaster/.