Frankfurter vs Tax Data
Same instrument, two spec sheets — measured, not claimed.
Frankfurter vs Tax Data: common questions
Which is more reliable, Frankfurter or Tax Data?
On our scheduled checks, Tax Data leads on measured uptime — Frankfurter at —% versus Tax Data at —% over 90 days. These are our own probe results, not provider claims; the uptime bars above show the day-by-day record for both.
Do Frankfurter and Tax Data need an API key?
Frankfurter needs no key, while Tax Data requires a free API key. If you want to start calling without signup, reach for Frankfurter first.
Can I call Frankfurter and Tax Data from the browser?
Yes — both Frankfurter and Tax Data send CORS headers over HTTPS, so front-end code can fetch either directly with no backend proxy. That makes them easy to swap in a client-side app while you compare responses.
Are Frankfurter and Tax Data free for commercial use?
Frankfurter allows commercial use on its free tier, and Tax Data has unclear commercial terms. We track service terms and the data license as separate fields — see the Commercial use and Data license rows above, and confirm both before shipping either in a paid product.