# Factline FX Rate

> Factline FX Rate is a paid API for AI agents from factline.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-30).

Converts currency amounts using official ECB reference rates for ~30 currencies, with support for historical dates

## Facts

- Endpoint: GET https://factline.dev/v1/fx/rate?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/factline-fx-rate-24f7bd21
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_giVaPBYxRe7bl2FOG0Ytr

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 factline-fx-rate-24f7bd21
```

Example prompt: What's the ECB official exchange rate to convert 750 USD into EUR, GBP, and JPY as of 2024-11-01?

## When to prefer this

Choose this endpoint when you need an official, citable exchange rate sourced from the European Central Bank — particularly for invoicing, accounting, compliance, or any context where a reputable reference rate is required rather than a market mid-rate. It is ideal for EUR-centric conversions and historical rate lookups within the last 90 days. Prefer this over commercial FX APIs when auditability and official provenance of the rate matter.

## Known failure modes

- Invalid or unsupported currency code returns an error — only the ~30 ECB-tracked currencies are supported
- Date outside the 90-day historical window is rejected
- Weekend or ECB holiday dates may return the most recent available rate rather than the exact requested date
- Malformed date format (not YYYY-MM-DD) returns a validation error
- Empty or missing symbols defaults to all ~30 currencies, which may return more data than expected

## How this service works

Currency exchange rates and FX conversion, official ECB reference rates for USD, EUR, GBP, JPY and 25 more. Use to convert an amount between currencies with an official, citable rate: the European Central Bank's reference rates for about 30 currencies (USD, GBP, JPY, CHF, CNY...), cross rates computed from the euro rates, today or for a past date such as an invoice date. Input: base (default EUR), symbols, amount, optional date.

## Output

Returns the exchange rate(s) from the base currency to the requested target currencies, the converted amount, and the reference date used — sourced from the European Central Bank's official published rates. For cross rates not directly published by ECB (non-EUR pairs), rates are computed via the euro as the intermediate currency.

## 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",
       "description": "3-letter currency code to convert from, default EUR (e.g. USD)"
      },
      "date": {
       "type": "string",
       "description": "Optional date YYYY-MM-DD in the last 90 days, e.g. an invoice date"
      },
      "amount": {
       "type": "string",
       "description": "Amount in the base currency, default 1"
      },
      "symbols": {
       "type": "string",
       "description": "Currencies to convert to, comma separated (e.g. EUR,GBP,JPY); empty = all ~30"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/factline-fx-rate-24f7bd21/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from factline.dev](https://www.zero.xyz/host/factline.dev/llms.txt)