gstinapi
Verify Indian GST numbers (GSTIN): legal name, status, address and return filing history; free tier
Post to and update maintenance and incidents on your status page through an HTTP REST API.
Instatus API is a free Business API that requires apiKey authentication, is served over HTTPS and has unconfirmed CORS support.
The Instatus REST API at api.instatus.com: authenticate with a bearer token and manage status pages, components, incidents, maintenances, subscribers and more.
Details from instatus.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.
Verify Indian GST numbers (GSTIN): legal name, status, address and return filing history; free tier
Parse and validate received e-invoices: XRechnung, ZUGFeRD, Peppol, FatturaPA, KSeF
The Instatus API is provided by Instatus Help (instatus.com). The Instatus REST API at api.instatus.com: authenticate with a bearer token and manage status pages, components, incidents, maintenances, subscribers and more.
Yes. The Instatus API is listed in the Business 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 Instatus API uses apiKey authentication, so you need to register for credentials before making requests.
CORS support for the Instatus API is unknown. Test a request from the browser, and fall back to a server-side call if it is blocked.
Yes. The Instatus API is served over HTTPS, so it's safe to use in production.