Build an EVM transaction ready to sign (never signed or sent)
Build an EVM transaction ready to sign (never signed or sent): native transfer, ERC-20 transfer or ERC-20 approve, with to, data, value, nonce, chainId, estimated gas and current EIP-1559 fees, plus a simulation that warns if it would revert and the estimated cost.
Not tested: has real-world effectsour last check, 2026-10-04
0 of 0checks answered this week
n/amedian answer time
$0.004listed price per call
n/aprice it asked us
Paid test badge: not yet. The checks above are free: we call the tool without paying and read the payment request it sends back. The Verified badge needs paid calls whose answers match the promised output, and nobody can buy a badge.
Endpoint
POST https://api.vextorium.com/v1/build-transaction
| Category | Everything else |
|---|---|
| Provider host | api.vextorium.com |
| Networks | eip155:10, eip155:5042, eip155:8453, solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp |
| Payment schemes | exact |
| Self-reported calls, 30 days | 1 from 1 payers (the provider's figure, not ours) |
Our checks, last 30 days
We never call tools that send, buy, move money or file anything, not even without paying.
Example input (from the provider)
{
"body": {
"action": "token_transfer",
"amount": 1,
"for": "0x9b9B3F22BEBD1e3E528C2759a2ca34cD2e0184A1",
"network": "base",
"since": "0xd8dA6BF26964aF9D7eed9e03E53415D37aA96045",
"token": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
},
"bodyType": "json",
"method": "POST",
"type": "http"
}
Promised output schema (from the provider)
{
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"properties": {
"action": {
"enum": [
"native_transfer",
"token_transfer",
"approve_token"
],
"type": "string"
},
"amount": {
"type": "number"
},
"for": {
"type": "string"
},
"network": {
"type": "string"
},
"since": {
"type": "string"
},
"token": {
"type": "string"
}
},
"required": [
"since",
"action",
"for",
"amount"
]
},
"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": {
"action": {
"type": [
"string",
"null"
]
},
"decimals": {
"type": [
"number",
"null"
]
},
"estimated_cost_usd": {
"type": [
"number",
"null"
]
},
"estimated_gas": {
"type": [
"number",
"null"
]
},
"estimated_native_cost": {
"type": [
"number",
"null"
]
},
"network": {
"type": [
"string",
"null"
]
},
"note": {
"type": [
"string",
"null"
]
},
"simulation": {
"type": [
"string",
"null"
]
},
"token": {
"type": [
"string",
"null"
]
},
"transaction": {
"properties": {
"chainId": {
"type": [
"string",
"null"
]
},
"data": {
"type": [
"string",
"null"
]
},
"from": {
"type": [
"string",
"null"
]
},
"gas": {
"type": [
"string",
"null"
]
},
"maxFeePerGas": {
"type": [
"string",
"null"
]
},
"maxPriorityFeePerGas": {
"type": [
"string",
"null"
]
},
"nonce": {
"type": [
"string",
"null"
]
},
"to": {
"type": [
"string",
"null"
]
},
"type": {
"type": [
"string",
"null"
]
},
"value": {
"type": [
"string",
"null"
]
}
},
"type": [
"object",
"null"
]
}
},
"type": [
"object",
"null"
]
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
}