Frankfurter
$0.01/call
Currency exchange rates and conversion using ECB data
Connect Frankfurter tools
Cursor
Claude Code
Claude Desktop
Windsurf
VS Code
Cline
Roo Code
ChatGPT
Gemini CLI
Amazon Q
Goose
Augment
n8n
API / cURL
AI SDK
TypeScript SDK
{
"mcpServers": {
"frankfurter": {
"url": "https://frankfurter.mcp.xpay.sh/mcp?key=YOUR_API_KEY"
}
}
}Or connect all tools
Access all tools (including Frankfurter) through a single MCP connection.
{
"mcpServers": {
"xpay": {
"url": "https://mcp.xpay.sh/mcp?key=YOUR_API_KEY"
}
}
}Agent Discovery
Machine-readable catalogs for LLM agents and automation.
curl https://xpay.tools/llms.txt
curl https://xpay.tools/agents.txt
curl https://xpay.tools/skill.md
Pricing
Pay per tool call. No subscriptions.
6 Frankfurter tools availableAbout Frankfurter
Frankfurter on xpay — ECB-grade FX rates with one MCP call
Frankfurter is an open-source FX rates API backed by the European Central Bank reference rates, with no API key required and no rate-limit gymnastics. It's the API you reach for when you need accurate-enough exchange rates without negotiating a contract with a paid FX vendor.
xpay wraps Frankfurter as MCP tools at $0.01 per call. You can call it directly from Claude Code, Cursor, VS Code, Windsurf, or Cline — your agent picks the tool, passes a date and currency pair, and gets back the rate.
What you can do
- Latest rates — current ECB reference rate for any currency vs. EUR or any base.
- Historical rates — single-day rates from 1999 onwards, or time-series across a date range.
- Conversion — pass amount + from + to and get the converted value at a chosen date.
When Frankfurter is right
- You need end-of-day reference rates for invoicing, accounting, reporting, settlements.
- You want historical FX time series for backtesting or financial dashboards.
- You're building an agent that occasionally needs FX context — e.g. "convert $1,200 USD to JPY at 2024-06-01."
- You want zero ongoing cost at low volume — $5 free credit covers ~500 calls.
When to use something else
- Real-time intraday FX (sub-day granularity) — Frankfurter is daily reference rates, not live. Use a market-data vendor.
- Crypto pairs — Frankfurter tracks fiat. For crypto see the dome / coingecko-style providers on xpay.
- Forward rates / volatility — not available; this is a spot reference API.
Why not just call frankfurter.app directly?
You can — Frankfurter is free. xpay adds value when:
- Your agent already runs in an MCP client. Frankfurter becomes one of dozens of providers your agent can pick autonomously.
- You want one bill across Frankfurter, FX vendors, market data, and other API providers on xpay.
- You want stability. xpay caches and falls back gracefully if Frankfurter has a hiccup.
- You're testing. $0.01/call is a rounding error vs. building HTTP plumbing for a one-off FX lookup.
Frequently Asked Questions
Frankfurter is a free open-source FX rates API backed by European Central Bank reference rates. It exposes latest, historical, and conversion endpoints — no API key required.
Frankfurter on xpay costs $0.01 per call. Frankfurter itself is free; xpay's value is the MCP wrapper, agent integration, unified billing across providers, and reliability. New accounts get $5 in free credits.
Frankfurter supports all currencies that the European Central Bank publishes reference rates for: USD, GBP, JPY, CHF, AUD, CAD, CNY, INR, BRL, ZAR, and ~30 more. Crypto pairs are not supported.
Daily ECB reference rates from January 4, 1999. You can request a single date or a time-series across a date range.
No. Frankfurter publishes ECB reference rates, which are end-of-day fixings (~16:00 CET on business days). For intraday or live rates you need a market-data vendor — Frankfurter is for accounting, reporting, and analytical use cases.
You need an xpay account (Google or email login, $5 free credit, no card). Frankfurter itself requires no signup, but to use it via the xpay MCP server you authenticate once with your xpay key.