This documents the new v2 API. For v1 docs, go here.

Frankfurter tracks daily exchange rates from 30+ central banks and official sources, covering 160 active currencies.

The public API lives at api.frankfurter.dev. No keys. Use anywhere. You can also self-host.

Rates

Fetch the latest exchange rates.

curl https://api.frankfurter.dev/v2/rates

Change the base currency with base. Filter target currencies with quote. 

curl https://api.frankfurter.dev/v2/rates?base=USD&quotes=EUR,GBP

Historical Rates

Look up rates for a specific date.

curl https://api.frankfurter.dev/v2/rates?date=1999-01-04

Time Series

Fetch rates over a period with from and to.

curl https://api.frankfurter.dev/v2/rates?from=2024-01-01&to=2024-01-05&quotes=USD

Tip: Narrowing down currencies keeps responses small. For large date ranges, request NDJSON to stream results line by line.

Grouping

Downsample a time series with group.

curl https://api.frankfurter.dev/v2/rates?from=2024-01-01&group=month

Filtering by Provider

Scope to specific providers with providers.

curl https://api.frankfurter.dev/v2/rates?providers=ECB

By default, rates are blended across all providers. Use providers to retrieve rates from a specific source.

CSV Output

Rates are also available as CSV. Append .csv to the path or set the Accept header to text/csv. 

curl https://api.frankfurter.dev/v2/rates.csv

NDJSON Output

For large responses, request NDJSON (newline-delimited JSON) by setting the Accept header to application/x-ndjson. Each line is one independent JSON object, useful for streaming large time series without buffering the entire response. 

curl -H "Accept: application/x-ndjson" \
  "https://api.frankfurter.dev/v2/rates?from=2024-01-01"

Rate

Get the rate for a single currency pair. Optionally add date or providers.

curl https://api.frankfurter.dev/v2/rate/EUR/USD

Currency

Get details and provider coverage for a single currency.

curl https://api.frankfurter.dev/v2/currency/EUR

Currencies

Get available currencies with provider coverage.

curl https://api.frankfurter.dev/v2/currencies

Providers

List the data sources behind the API.

curl https://api.frankfurter.dev/v2/providers

Conversion

Fetch the rate and convert in your own code. 

const API = "https://api.frankfurter.dev";

function convert(base, quote, amount) {
  const path = `/v2/rates?base=${base}&quotes=${quote}`;
  fetch(API + path)
    .then((r) => r.json())
    .then((data) => {
      const result = (amount * data[0].rate).toFixed(2);
      alert(`${amount} ${base} = ${result} ${quote}`);
    });
}

convert("EUR", "USD", 10);

Errors

The API returns standard HTTP status codes with a JSON body. 

{
  "message": "Could not find currency ABC"
}
400
Invalid parameter or malformed request.
404
Currency, rate, or resource not found.
422
Request understood but cannot be processed.

Self-Hosting

You can self-host with Docker. See the deploy guide for production setup and API key configuration.

FAQ

Is the API free for commercial use?
Yes, absolutely.
Does the API have any call limits?
There are no quotas. Requests are rate-limited to prevent abuse, but there are no monthly or daily caps. For high-volume use, consider caching responses or self-hosting.
Is the v1 API being retired?
No. The v1 API will continue to work. See the v1 documentation.
What is the privacy policy of the API?
The API itself does not collect personal data. However, the public app runs behind Cloudflare for performance, and Cloudflare will collect some basic information for analytics. This does not apply if you run the API privately.
Where can I report a bug or ask a question?
Open an issue to report a bug, request a feature, or suggest a new data source. Use Discussions to ask questions or share a library or tool you built with Frankfurter.
How accurate are the rates?
For compliance, filter by a specific provider to get official reference rates. For general use, the default blended rates work well, though the last decimal places may shift as new data comes in.
What happened to api.frankfurter.app?
This domain used to host the older, unversioned API. It now redirects to v1. The response is identical aside from the redirect hop. Please update to the current API.
Why is it called Frankfurter?
Frankfurt is home to the European Central Bank, the original data source of this project.