# FX Reference Rates API – Latest Rates

> FX Reference Rates API – Latest Rates is a paid API for AI agents from fx-reference-rates.regnotes.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-30).

Returns the most recent ECB foreign exchange reference rates expressed in a requested base currency, optionally filtered to specific currency symbols.

## Facts

- Endpoint: GET https://fx-reference-rates.regnotes.workers.dev/v1/rates/latest?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fx-reference-rates-api-latest-rates-b37dab71
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_jRR02iCkE4Ko3w1ZUdC-_

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability fx-reference-rates-api-latest-rates-b37dab71
```

Example prompt: What are the latest ECB reference rates with USD as the base currency, showing EUR, JPY, and GBP?

## When to prefer this

Choose this endpoint when you need the latest available ECB official reference rates (as opposed to a specific historical date or a date range). It is ideal for real-time pricing, FX exposure checks, or currency conversion when only the most current rate matters. If you need rates for a specific past date or a time series, use the historical or date-specific sibling endpoints instead.

## Known failure modes

- Invalid base currency code (not matching ^[A-Z]{3}$ or not in supported list) returns an error
- Unsupported symbol codes in the symbols filter may be silently ignored or return an error
- ECB non-publication days (weekends/holidays) may return the most recent prior published rates
- Payment failure (insufficient USDC balance) returns 402 Payment Required
- Network timeout from the Cloudflare Worker edge node

## How this service works

Most recent ECB reference rates expressed in the requested base currency.

## Output

A JSON object containing the base currency code, the date the rates were published (as_of), and a map of currency codes to their exchange rate values relative to the base currency. Example: {"base":"USD","as_of":"2026-10-23","rates":{"EUR":0.893,"JPY":156.8,"CNY":6.67}}.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "base": {
       "type": "string",
       "pattern": "^[A-Z]{3}$",
       "description": "One of: AUD, BRL, CAD, CHF, CNY, CZK, DKK, EUR, GBP, HKD, HUF, IDR, ILS, INR, ISK, JPY, KRW, MXN, MYR, NOK, NZD, PHP, PLN, RON, SEK, SGD, THB, TRY, USD, ZAR"
      },
      "symbols": {
       "type": "string",
       "description": "Comma-separated ISO 4217 codes"
      }
     },
     "additionalProperties": false
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "base": "USD",
  "as_of": "2026-10-23",
  "rates": {
   "CNY": 6.67024,
   "EUR": 0.8934155,
   "JPY": 156.8034
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fx-reference-rates-api-latest-rates-b37dab71/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fx-reference-rates.regnotes.workers.dev](https://www.zero.xyz/host/fx-reference-rates.regnotes.workers.dev/llms.txt)