Instant IBAN and SWIFT number validation across the globe.
Bank Data API is a free Finance API that requires apiKey authentication, is served over HTTPS and has unconfirmed CORS support.
Instant IBAN and SWIFT number validation across the globe.
Details from apilayer.com.

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Geocode an address, validate an email, track a flight or pull stock data with one account, one dashboard and one API key.
Which US business banking providers accept founders by country of residence, with sources
The Bank Data API is provided by APILayer (apilayer.com). Instant IBAN and SWIFT number validation across the globe.
Yes. The Bank Data API is listed in the Finance category of the public-apis directory, which only includes APIs that are free or have a free tier. Check its documentation for rate limits and paid plans.
Yes. The Bank Data API uses apiKey authentication, so you need to register for credentials before making requests.
CORS support for the Bank Data API is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
Yes. The Bank Data API is served over HTTPS, so it's safe to use in production.