Fixer

Exchange rates and currency conversion

Fixer is a widely-used foreign exchange rate API that provides real-time and historical exchange rates for 170 world currencies. Powered by data from the European Central Bank, it offers endpoints for latest rates, historical rates, currency conversion, time-series data, and fluctuation tracking. For OpenClaw agents, Fixer is a straightforward option for currency conversion tasks — converting SaaS pricing between USD and INR, tracking exchange rate movements, or generating currency reports. However, note that the free tier only supports HTTP (not HTTPS) and EUR as the base currency, which limits its usefulness without upgrading.

Tags: finance, currency

Category: Currency Exchange

Use Cases

  • Convert between currencies when discussing international SaaS pricing
  • Track daily exchange rate movements via cron and alert on significant changes
  • Generate historical currency rate charts for business planning

Tips

  • Cache exchange rates aggressively — they update only once daily on most plans
  • If you just need EUR-based rates, the free tier works fine with local base conversion math
  • Consider Open Exchange Rates or ECB data as free alternatives with fewer restrictions

Known Issues & Gotchas

  • Free tier is HTTP-only — no HTTPS, which is a dealbreaker for secure environments
  • EUR is the only base currency on free tier — you must convert manually for other bases
  • 100 requests/month on free is very restrictive for any automated workflow

Frequently Asked Questions

Why does the free tier only return EUR as the base?

Fixer's free plan locks the base currency to EUR. To use USD or any other base, you need at least the Basic paid plan. You can work around this by doing the math client-side.

Does Fixer support HTTPS on the free plan?

No. The free plan only supports HTTP, which is a security concern. HTTPS is available starting from the Basic plan at $14.99/month.

How does Fixer compare to Exchangerate.host?

Fixer is more established and reliable but has a restrictive free tier. Exchangerate.host offers a more generous free tier but has been adding restrictions recently. For paid use, Fixer's data quality is excellent.