Encode a contract call: give a function signature and a JSON array of arguments,...
https://saylorinnovations.com/api/chain/encode-callOverview
Encode a contract call: give a function signature and a JSON array of arguments, get calldata and the 4-byte selector. Computed locally, no node needed.
Protocol
x402
Price
$0.01
Payment Asset
USD Coin
Payment Network
eip155:8453
Category
uncategorized
Provider
Saylor Innovations Data Desk
Source
bazaar
Indexed
2026-10-21 04:24:46
Health
Status
healthy
Latency (p50)
373ms
Uptime (30d)
100.0%
Reliability Score
95/100
Last Checked
2026-10-28 16:17:12
Last Healthy
2026-10-28 16:17:12
Consecutive Failures
0
x402 Payment Validation
Payment Requirements
Valid
Asset Verified
Known USDC
Facilitator
—
Input Schema
{
"method": "GET",
"queryParams": {
"args": "[\"0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045\",\"1000000\"]",
"signature": "transfer(address,uint256)"
},
"type": "http"
}
Output Schema
{
"example": {
"argument_types": [
"address",
"uint256"
],
"calldata": "0xa9059cbb000000000000000000000000d8da6bf26964af9d7eed9e03e53415d37aa9604500000000000000000000000000000000000000000000000000000000000f4240",
"calldata_bytes": 68,
"note": "Computed locally. Use calldata as the data field of a transaction, or as the data parameter of /api/chain/call to read from a contract.",
"selector": "0xa9059cbb",
"signature": "transfer(address,uint256)",
"source": "Computed locally (viem ABI encoding)"
},
"type": "json"
}
Recent Health Checks
| Time | Status | HTTP | Latency | Error |
|---|---|---|---|---|
| 2026-10-28 16:17:12 | healthy | 402 | 450ms | |
| 2026-10-28 15:24:25 | healthy | 402 | 753ms | |
| 2026-10-28 14:18:57 | healthy | 402 | 2503ms | |
| 2026-10-28 07:03:13 | healthy | 402 | 251ms | |
| 2026-10-28 05:40:16 | healthy | 402 | 475ms | |
| 2026-10-28 04:42:40 | healthy | 402 | 339ms | |
| 2026-10-28 03:48:38 | healthy | 402 | 330ms | |
| 2026-10-28 02:49:01 | healthy | 402 | 373ms | |
| 2026-10-28 01:44:34 | healthy | 402 | 282ms | |
| 2026-10-28 00:38:17 | healthy | 402 | 310ms | |
| 2026-10-27 23:41:53 | healthy | 402 | 307ms | |
| 2026-10-27 22:55:41 | healthy | 402 | 408ms | |
| 2026-10-27 21:45:02 | healthy | 402 | 527ms | |
| 2026-10-27 20:30:18 | healthy | 402 | 313ms | |
| 2026-10-27 19:25:01 | healthy | 402 | 392ms | |
| 2026-10-26 11:19:36 | healthy | 402 | 2847ms | |
| 2026-10-25 22:38:01 | healthy | 402 | 287ms |