Solidity ABI calldata encoder — encode canonical typed values for an EVM smart-contract fu
Solidity ABI calldata encoder — encode canonical typed values for an EVM smart-contract function call, with an optional selector and exact 256-bit integers.
5000 (raw units)
price
2
calls / 30d
1
unique payers
2026-09-15
updated
Provider
chain-tools.use.x402atlas.com · discovered, not yet claimed by its owner
Payment (x402 accepts[])
[
{
"scheme": "exact",
"network": "eip155:8453",
"payTo": "0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2",
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"amount": "5000",
"maxTimeoutSeconds": 300
},
{
"scheme": "exact",
"network": "eip155:137",
"payTo": "0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2",
"asset": "0x3c499c542cEF5E3811e1192ce70d8cC03d5c3359",
"amount": "5000",
"maxTimeoutSeconds": 300
},
{
"scheme": "exact",
"network": "eip155:42161",
"payTo": "0x8C128f1Ee62Bb5e47867CfbAe2ad89be325Df1b2",
"asset": "0xaf88d065e77c8cC2239327C5EDb3A432268e5831",
"amount": "5000",
"maxTimeoutSeconds": 300
}
]Output schema
{
"bazaar": {
"category": "utilities",
"info": {
"input": {
"body": {
"function": "transfer",
"include_selector": true,
"types": [
"address",
"uint256"
],
"values": [
"0x0000000000000000000000000000000000000001",
"1000"
]
},
"bodyType": "json",
"method": "POST",
"type": "http"
},
"output": {
"example": {
"algorithm_version": "solidity-abi-v1",
"data": "0xa9059cbb000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000003e8",
"function_signature": "transfer(address,uint256)",
"include_selector": true,
"operation": "abi-encode",
"payload": "0x000000000000000000000000000000000000000000000000000000000000000100000000000000000000000000000000000000000000000000000000000003e8",
"selector": "0xa9059cbb",
"types": [
"address",
"uint256"
],
"values": [
"0x0000000000000000000000000000000000000001",
"1000"
],
"warnings": []
},
"type": "json"
}
},
"schema": {
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {
"input": {
"additionalProperties": false,
"properties": {
"body": {
"additionalProperties": false,
"description": "One bounded standard Solidity ABI encoding request",
"oneOf": [
{
"properties": {
"include_selector": {
"const": true
}
},
"required": [
"function"
]
},
{
"not": {
"required": [
"function"
]
},
"properties": {
"include_selector": {
"const": false
}
}
}
],
"properties": {
"function": {
"description": "Function identifier required exactly when include_selector is true; never a full signature",
"pattern": "^[A-Za-z_][A-Za-z0-9_]*$",
"type": "string"
},
"include_selector": {
"description": "Whether to prepend the four-byte selector for function and canonical types",
"type": "boolean"
},
"types": {
"description": "Supported canonical Solidity ABI types; uint/int aliases normalize to 256-bit forms",
"items": {
"description": "One closed-grammar ABI type with maximum nesting depth four",
"type": "string"
},
"maxItems": 32,
"minItems": 0,
"type": "array"
},
"values": {
"description": "Positional JSON values exactly matching types; integers are decimal strings",
"items": {
"description": "Boolean, string, byte/address/integer string, or positional tuple/array value as required by its type"
},
"maxItems": 32,
"minItems": 0,
"type": "array"
}
},
"required": [
"types",
"values",
"include_selector"
],
"type": "object"
},
"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": {
"additionalProperties": false,
"properties": {
"_atlas": {
"additionalProperties": false,
"description": "Atlas documentation and related-route metadata added after deployment",
"properties": {
"docs": {
"description": "Documentation URL for this bridge",
"format": "uri",
"maxLength": 512,
"type": "string"
},
"related": {
"description": "Bounded related Atlas routes",
"items": {
"additionalProperties": false,
"description": "One related Atlas route",
"properties": {
"bridge": {
"description": "Related bridge name",
"maxLength": 64,
"type": "string"
},
"docs": {
"description": "Related bridge documentation URL",
"format": "uri",
"maxLength": 512,
"type": "string"
},
"summary": {
"description": "Short capability summary",
"maxLength": 256,
"type": "string"
},
"url": {
"description": "Related route URL",
"format": "uri",
"maxLength": 512,
"type": "string"
}
},
"required": [
"bridge",
"url",
"docs",
"summary"
],
"type": "object"
},
"maxItems": 3,
"type": "array"
}
},
"required": [
"docs"
],
"type": "object"
},
"algorithm_version": {
"const": "solidity-abi-v1",
"description": "Pinned Solidity ABI grammar and byte contract",
"type": "string"
},
"data": {
"description": "Complete encoded bytes, including selector when requested",
"pattern": "^0x(?:[0-9a-f]{2})*$",
"type": "string"
},
"function_signature": {
"description": "Canonical signature when selector included",
"type": "string"
},
"include_selector": {
"description": "Whether data begins with selector",
"type": "boolean"
},
"operation": {
"const": "abi-encode",
"description": "Stable route operation",
"type": "string"
},
"payload": {
"description": "Selector-free canonical ABI payload",
"pattern": "^0x(?:[0-9a-f]{2})*$",
"type": "string"
},
"selector": {
"description": "Four-byte selector when included",
"pattern": "^0x(?:[0-9a-f]{2})*$",
"type": "string"
},
"types": {
"description": "Canonical ABI types",
"items": {
"description": "Canonical Solidity ABI type",
"type": "string"
},
"type": "array"
},
"values": {
"description": "Normalized values in exact type order",
"items": {
"description": "Normalized exact JSON representation"
},
"type": "array"
},
"warnings": {
"description": "Always empty for deterministic offline computation",
"items": {
"description": "Warning",
"type": "string"
},
"maxItems": 0,
"type": "array"
}
},
"required": [
"operation",
"algorithm_version",
"types",
"values",
"include_selector",
"payload",
"data",
"warnings"
],
"type": "object"
},
"type": {
"type": "string"
}
},
"required": [
"type"
],
"type": "object"
}
},
"required": [
"input"
],
"type": "object"
},
"tags": [
"abi-encode",
"solidity-abi",
"evm",
"blockchain-development",
"offline-computation"
]
}
}Use it
curl
curl "https://chain-tools.use.x402atlas.com/evm/abi-encode" # -> 402 Payment Required, accepts[] lists how to pay # retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid
JavaScript
const res = await fetch("https://chain-tools.use.x402atlas.com/evm/abi-encode");
if (res.status === 402) {
const { accepts } = await res.json();
// pay one of accepts[] via an x402 client, then retry with the payment header
}Python
import httpx
res = httpx.get("https://chain-tools.use.x402atlas.com/evm/abi-encode")
if res.status_code == 402:
accepts = res.json()["accepts"]
# pay one of accepts[] via an x402 client, then retry with the payment headerMachine-readable
Everything on this page is also available as clean JSON at /resources/3460.json, and this resource appears in /discovery/resources and /discovery/search.