Ref Currency
by Duo Data Utilities in Markets & finance
Look up a currency by its ISO 4217 alphabetic or numeric code: the official English name, minor-unit exponent, fund flag, the smallest cash denomination where it differs from the minor unit, the territories that use it, and historic codes on request. Returns the correct rounding increment for cash amounts, which is what a caller needs to render or settle a price. This route returns currency facts only and never an exchange rate.
https://api.duoleads.com/v1/ref/currency- Price
- $0.05
- per call in USDC
- Uptime
- 100%
- last 30 days
- Response time
- 144 ms
- 851 ms slowest 5%
- Last check
- Passed
- 3 h ago, next any minute now
Reliability
How to call it
GET https://api.duoleads.com/v1/ref/currency
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/ref/currency?code=EUR&include=territoriesParameters
| Parameter | Type | Required | Description |
|---|---|---|---|
code | string | No | ISO 4217 alpha-3 or 3-digit numeric code. |
country | string | No | ISO 3166-1 alpha-2; returns the currencies in use there. |
include | string | No | Comma-separated: territories, historic. Default none. |
Example response
The provider's example. We can't check it without paying. Shortened for display.
Example response, 61 lines
{
"data": {
"cash_minor_units": 2,
"cash_rounding": null,
"code": "EUR",
"found": true,
"is_fund": false,
"minor_units": 2,
"name": "Euro",
"numeric": "978",
"status": "current",
"territories": [
"AD",
"AT",
"AX",
"BE",
"BG",
"BL",
"CY",
"DE",
"EE",
"ES",
"FI",
"FR",
"GF",
"GP",
"GR",
"HR",
"IE",
"IT",
"LT",
"LU"
]
},
"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": "ISO 4217 currency and funds code lists, published by SIX Group as secretariat of the ISO 4217 Maintenance Agency (public data)",
"id": "iso-4217",
"licence": "Public data (owner decision 2026-09-29)",
"published": "2026-09-17",
"version": "SIX list one 2026-09-17, list three 2026-01-01"
},
{
"attribution": "Unicode CLDR, © Unicode, Inc.",
"id": "cldr-currency-data",
"licence": "Unicode-3.0",
"published": "2026-09-28",
"version": "48.2.2"
}
]
},
"ok": true,
"route": "/v1/ref/currency",
"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/ref/currency?code=EUR&include=territories'
# 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/ref/currency?code=EUR&include=territories' \
| 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%2Fref%2Fcurrency
const res = await pay("https://api.duoleads.com/v1/ref/currency?code=EUR&include=territories");
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/ref/currency?code=EUR&include=territories")
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 |
|---|---|---|---|---|
| 3 h ago | Passed | 402 | 907 ms | $0.05 |
| 7 h ago | Passed | 402 | 67 ms | $0.05 |
| 11 h ago | Passed | 402 | 143 ms | $0.05 |
| 15 h ago | Passed | 402 | 616 ms | $0.05 |
| 20 h ago | Passed | 402 | 242 ms | $0.05 |
Show 10 older checks
| 24 h ago | Passed | 402 | 538 ms | $0.05 |
| 28 h ago | Passed | 402 | 49 ms | $0.05 |
| 32 h ago | Passed | 402 | 127 ms | $0.05 |
| 36 h ago | Passed | 402 | 114 ms | $0.05 |
| 39 h ago | Passed | 402 | 158 ms | $0.05 |
| 43 h ago | Passed | 402 | 127 ms | $0.05 |
| 47 h ago | Passed | 402 | 183 ms | $0.05 |
| 2 days ago | Passed | 402 | 851 ms | $0.05 |
| 2 days ago | Passed | 402 | 186 ms | $0.05 |
| 2 days ago | Passed | 402 | 42 ms | $0.05 |