Id Iban Build
by Duo Data Utilities in Markets & finance
Construct an IBAN from a country code and the domestic account parts, computing the ISO 7064 mod-97-10 check digits. Takes either a single BBAN string or named parts (bank code, branch code, account number); digit fields are left-padded with zeros to the country's registered widths. Returns the IBAN in electronic and print formats with its bank, branch and account parts. Covers the 89 SWIFT registry countries. Named parts work only where they span the whole BBAN; otherwise pass the BBAN.
https://api.duoleads.com/v1/id/iban-build- Price
- $0.05
- per call in USDC
- Uptime
- 100%
- last 30 days
- Response time
- 152 ms
- 543 ms slowest 5%
- Last check
- Passed
- 4 h ago, next any minute now
Reliability
How to call it
GET https://api.duoleads.com/v1/id/iban-build
Each call costs $0.05 in USDC on Base, paid with the request over x402.
Run a free test callOne unpaid request, the way an agent sends it. You see the payment challenge it gets back. Nothing is charged.
Example request
From the listing.
GET https://api.duoleads.com/v1/id/iban-build?account=0417164300&bank=ABNA&country=NLParameters
| Parameter | Type | Required | Description |
|---|---|---|---|
account | string | No | Account number. Requires bank. |
bank | string | No | Bank code. Requires account. |
bban | string | No | The whole domestic account number (BBAN), alphanumeric. Use this or bank plus account. |
branch | string | No | Branch code, for countries whose layout has a branch field. |
country | string | Yes | ISO 3166-1 alpha-2 country code in the SWIFT IBAN registry, case-insensitive. |
Example response
The provider's example. We can't check it without paying.
Example response, 35 lines
{
"data": {
"bban": "ABNA0417164300",
"check_digits": "91",
"country": "NL",
"iban": "NL91ABNA0417164300",
"iban_print": "NL91 ABNA 0417 1643 00",
"length": 18,
"parts": {
"account": "0417164300",
"bank": "ABNA",
"branch": null
},
"valid": true
},
"meta": {
"computed_at": "2026-09-28T12:00:00.000Z",
"deterministic": true,
"disclaimer": "Factual output of a deterministic computation over public data. Provided as is, with no warranty of accuracy, completeness or availability. Not investment, financial, legal, tax, medical or any other professional advice, and not a recommendation. Verify before relying on it. Terms: https://api.duoleads.com/terms",
"price_usd": "0.05",
"request_id": "01K6B7Q4ZC8H3F2M9WXR5TYN0D",
"sources": [
{
"attribution": "IBAN registry via ibantools (MIT); field offsets via schwifty (MIT); underlying data: SWIFT IBAN Registry, public",
"id": "iban-registry",
"licence": "MIT",
"published": "2026-04-10",
"version": "ibantools 4.5.4, field layout schwifty 2026.7.3"
}
]
},
"ok": true,
"route": "/v1/id/iban-build",
"version": "1.0.0"
}Call it from code
The curl command shows the payment challenge. The JavaScript and Python versions pay and call, and never pay more than $0.05.
curl: see the payment challenge
# bash or zsh: see the payment challenge. Nothing is charged.
curl -sS -g -i 'https://api.duoleads.com/v1/id/iban-build?account=0417164300&bank=ABNA&country=NL'
# x402 v2 sends the challenge base64-encoded in the PAYMENT-REQUIRED header (v1 sends it in the body).
# To read the header:
curl -sS -g -o /dev/null -D - 'https://api.duoleads.com/v1/id/iban-build?account=0417164300&bank=ABNA&country=NL' \
| grep -i '^payment-required:' | cut -d' ' -f2 | tr -d '\r' | base64 --decodeJavaScript: pay and call
// npm i @x402/fetch @x402/evm viem
import { wrapFetchWithPayment, x402Client } from "@x402/fetch";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";
// Pays at most $0.05 per call.
const client = new x402Client().setSpendControls({ maxAmountPerPayment: "$0.05" });
registerExactEvmScheme(client, { signer: privateKeyToAccount(process.env.EVM_PRIVATE_KEY) });
const pay = wrapFetchWithPayment(fetch, client);
// Not sure it's safe to pay? ToolVet checks it first for $0.005. Pay for that from a separate
// client: this one is capped at $0.05 per payment. GET https://toolvet.app/api/v1/check?url=https%3A%2F%2Fapi.duoleads.com%2Fv1%2Fid%2Fiban-build
const res = await pay("https://api.duoleads.com/v1/id/iban-build?account=0417164300&bank=ABNA&country=NL");
console.log(res.status, await res.text());Python: pay and call
# pip install "x402[requests,evm]"
import os
from eth_account import Account
from x402 import x402ClientSync
from x402.http.clients import x402_requests
from x402.mechanisms.evm import EthAccountSigner
from x402.mechanisms.evm.exact.register import register_exact_evm_client
# Pays at most $0.05 per call.
client = x402ClientSync().set_spend_controls({"max_amount_per_payment": "$0.05"})
register_exact_evm_client(client, EthAccountSigner(Account.from_key(os.environ["EVM_PRIVATE_KEY"])))
with x402_requests(client) as session:
res = session.get("https://api.duoleads.com/v1/id/iban-build?account=0417164300&bank=ABNA&country=NL")
print(res.status_code, res.text)Security scan
No findings
We scan names, descriptions and tool definitions for hidden instructions and other prompt-injection patterns.
Recent checks
| When | Result | HTTP | Time | Price |
|---|---|---|---|---|
| 4 h ago | Passed | 402 | 90 ms | $0.05 |
| 8 h ago | Passed | 402 | 166 ms | $0.05 |
| 12 h ago | Passed | 402 | 152 ms | $0.05 |
| 16 h ago | Passed | 402 | 38 ms | $0.05 |
| 21 h ago | Passed | 402 | 543 ms | $0.05 |
Show 10 older checks
| 25 h ago | Passed | 402 | 282 ms | $0.05 |
| 29 h ago | Passed | 402 | 273 ms | $0.05 |
| 33 h ago | Passed | 402 | 198 ms | $0.05 |
| 37 h ago | Passed | 402 | 163 ms | $0.05 |
| 40 h ago | Passed | 402 | 124 ms | $0.05 |
| 44 h ago | Passed | 402 | 41 ms | $0.05 |
| 2 days ago | Passed | 402 | 546 ms | $0.05 |
| 2 days ago | Passed | 402 | 129 ms | $0.05 |
| 2 days ago | Passed | 402 | 46 ms | $0.05 |
| 2 days ago | Passed | 402 | 43 ms | $0.05 |