Explain an EIP-712 typed-data signature before signing it
Explain an EIP-712 typed-data signature before signing it: x402/EIP-3009 payment authorizations, EIP-2612 permits, Permit2 and Seaport orders. Flags unlimited allowances, long validity and non-official tokens, and returns the exact hash to compare with your wallet.
Answeringour last check, 2026-09-29
1 of 1checks answered this week
327 msmedian answer time
$0.005listed price per call
$0.005price it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
POST https://api.vextorium.com/revisar-firma-pago
| Category | Market data |
|---|---|
| Provider host | api.vextorium.com |
| Networks | eip155:8453, solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp |
| Payment schemes | exact |
| Self-reported calls, 30 days | 1 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
| Day | Result | HTTP | Asked | Time |
|---|---|---|---|---|
| 2026-09-29 | valid payment request | 402 | $0.005 | 327 ms |
Example input (from the provider)
{
"body": {
"datos_firma": {
"domain": {
"chainId": 8453,
"name": "USD Coin",
"verifyingContract": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"version": "2"
},
"message": {
"from": "0x1111111111111111111111111111111111111111",
"nonce": "0xabababababababababababababababababababababababababababababababab",
"to": "0x2222222222222222222222222222222222222222",
"validAfter": "1790634093",
"validBefore": "1790634453",
"value": "10000"
},
"primaryType": "TransferWithAuthorization",
"types": {
"TransferWithAuthorization": [
{
"name": "from",
"type": "address"
},
{
"name": "to",
"type": "address"
},
{
"name": "value",
"type": "uint256"
},
{
"name": "validAfter",
"type": "uint256"
},
{
"name": "validBefore",
"type": "uint256"
},
{
"name": "nonce",
"type": "bytes32"
}
]
}
}
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"properties": {
"datos_firma": {
"description": "EIP-712 object as passed to eth_signTypedData_v4: domain, types, primaryType, message",
"type": "object"
}
},
"required": [
"datos_firma"
]
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"type": {
"const": "http",
"type": "string"
}
},
"required": [
"type",
"method",
"bodyType",
"body"
],
"type": "object"
},
"output": {
"properties": {
"example": {
"properties": {
"alertas": {
"items": {},
"type": [
"array",
"null"
]
},
"aplicacion": {
"type": [
"string",
"null"
]
},
"contrato_verificador": {
"type": [
"string",
"null"
]
},
"hash_a_firmar": {
"type": [
"string",
"null"
]
},
"hash_del_mensaje": {
"type": [
"string",
"null"
]
},
"nota": {
"type": [
"string",
"null"
]
},
"red": {
"type": [
"string",
"null"
]
},
"resumen": {
"properties": {
"accion": {
"type": [
"string",
"null"
]
},
"desde": {
"type": [
"string",
"null"
]
},
"importe": {
"type": [
"string",
"null"
]
},
"para": {
"type": [
"string",
"null"
]
},
"token": {
"type": [
"string",
"null"
]
},
"valido_desde": {
"type": [
"string",
"null"
]
},
"valido_hasta": {
"type": [
"string",
"null"
]
}
},
"type": [
"object",
"null"
]
},
"separador_de_dominio": {
"type": [
"string",
"null"
]
},
"tipo": {
"type": [
"string",
"null"
]
},
"veredicto": {
"type": [
"string",
"null"
]
}
},
"type": [
"object",
"null"
]
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}