# SpruceID Sign-In with Ethereum (SIWE) API

**Canonical:** https://apis.io/apis/spruceid/spruceid-sign-in-with-ethereum-siwe-api/  
**Provider:** SpruceID — https://apis.io/providers/spruceid/  
**Base URL:** https://oidc.spruceid.com  
**Documentation:** https://eips.ethereum.org/EIPS/eip-4361

SpruceID Sign-In with Ethereum (SIWE) API is one of 10 APIs that [SpruceID](https://apis.io/providers/spruceid/) publishes on the [APIs.io](https://apis.io/) network. Tagged areas include Authentication, Sign-In with Ethereum, SIWE, OpenID Connect, and Ethereum. The published artifact set on APIs.io includes API documentation and a GitHub repository.

Sign-In with Ethereum (SIWE) enables Ethereum accounts to authenticate with off-chain services by signing a standardized message format (EIP-4361). SpruceID's SIWE library provides client and server implementations in TypeScript for integrating Ethereum wallet-based authentication into web applications. The SIWE-OIDC component wraps SIWE in an OpenID Connect Identity Provider, enabling drop-in integration with OAuth 2.0 and OIDC flows. Supported wallets include MetaMask, Coinbase Wallet, and any WalletConnect-compatible wallet. ENS domain resolution is included for human-readable usernames.

## Machine-readable artifacts (5)

- **Documentation** — https://spruceid.dev/docs/
- **GitHubRepository** — https://github.com/spruceid/siwe
- **GitHubRepository** — https://github.com/spruceid/siwe-oidc
- **NPMPackage** — https://www.npmjs.com/package/siwe
- **APIsJSON** — https://raw.githubusercontent.com/api-evangelist/spruceid/refs/heads/main/apis.yml

## Other SpruceID APIs (9)

- [SpruceID SSI Core Library API](https://apis.io/apis/spruceid/spruceid-ssi-core-library-api/)
- [SpruceID OID4VCI Credential Issuance API](https://apis.io/apis/spruceid/spruceid-oid4vci-credential-issuance-api/)
- [SpruceID OID4VP Verifiable Presentations API](https://apis.io/apis/spruceid/spruceid-oid4vp-verifiable-presentations-api/)
- [SpruceID isomdl Mobile Driver's License API](https://apis.io/apis/spruceid/spruceid-isomdl-mobile-drivers-license-api/)
- [SpruceID Credentials API](https://apis.io/apis/spruceid/spruceid-credentials-api/)
- [SpruceID Health API](https://apis.io/apis/spruceid/spruceid-health-api/)
- [SpruceID Identifiers API](https://apis.io/apis/spruceid/spruceid-identifiers-api/)
- [SpruceID Presentations API](https://apis.io/apis/spruceid/spruceid-presentations-api/)
- [SpruceID Status API](https://apis.io/apis/spruceid/spruceid-status-api/)

## Tags

Authentication, Sign-In with Ethereum, SIWE, OpenID Connect, Ethereum, Blockchain Identity

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/apis/spruceid/spruceid-sign-in-with-ethereum-siwe-api/). The API's provider profile, Kin Score and agent-readiness rating are at https://apis.io/providers/spruceid/.