Web3 Authentication

Get SIWE challenge message

Get a single-use SIWE (Sign-In with Ethereum) challenge message for existing-wallet sign-in, wallet key management, or paid x402 access. The nonce expires after 10 minutes. A challenge does not create a Free account.

post/v1/auth/web3/challenge

Request

  • Base URL: https://api.0xarchive.io
  • URL: https://api.0xarchive.io/v1/auth/web3/challenge
  • Auth: none required

Request body

addressstring required

Ethereum wallet address

Example request

{
  "address": "0x742d35Cc6634C0532925a3b844Bc9e7595f2bD18"
}

Response

SIWE challenge message

messagestring

SIWE message to sign with personal_sign (EIP-191)

noncestring

Single-use nonce (expires after 10 minutes)

Changes

No recorded changes to this operation across all 1 revision of this API.