Free Open Exchange Rate API — No API Key Required

A free, keyless exchange rate endpoint for tutorials, prototypes and small sites. Live mid-market rates for 150+ currencies, CORS enabled, no signup — just keep the attribution link.

Free Open Exchange Rate API

A keyless, signup-free endpoint with the same live mid-market rates as the full AllRatesToday API. Built for tutorials, classroom projects, prototypes and small sites — your first code block just works.

The deal is simple: the open endpoint is free for everyone, and in return we ask that any page or project using it shows a visible attribution link:

<a href="https://allratestoday.com">Rates by AllRatesToday</a>

That one link is what keeps the open endpoint free.

The endpoint

curl "https://allratestoday.com/api/rate?source=USD&target=EUR"

Response:

{ "rate": 0.864566, "source": "refinitiv" }

No API key, no signup — works immediately
150+ currencies — any ISO 4217 pair via source and target
Live mid-market rates — same data source as the paid tiers
CORS enabled (Access-Control-Allow-Origin: *) — call it straight from the browser

Quick examples

JavaScript

// Works in the browser too — the endpoint sends CORS headers.
const res = await fetch(
  'https://allratestoday.com/api/rate?source=USD&target=EUR'
);
const { rate } = await res.json();
console.log(`1 USD = ${rate} EUR`);

Python

import requests

r = requests.get(
    "https://allratestoday.com/api/rate",
    params={"source": "USD", "target": "EUR"},
)
print(f"1 USD = {r.json()['rate']} EUR")

Want a ready-made UI instead? The embeddable currency converter widget uses this same endpoint and needs no key either.

Fair use

The open endpoint is a shared community resource. It's perfect for tutorials, demos, open-source samples, and low-traffic sites. There's no hard published quota, but sustained heavy traffic may be throttled to keep it fast for everyone. Cache responses where you can — rates don't change every second.

When to get a (free) API key

If your project grows, register for a free key — no credit card — and you get dedicated quota, usage stats in your dashboard, plus the full API: authenticated rates, historical data, and the complete reference. Paid tiers add higher limits — see pricing.

Attribution examples

Anywhere visible on the page or project is fine — footer, about page, or README:

HTML: <a href="https://allratestoday.com">Rates by AllRatesToday</a>
Markdown: Rates by [AllRatesToday](https://allratestoday.com)
Plain text (apps, slides): Exchange rates by AllRatesToday — allratestoday.com