host-t.com
Basic DNS query via HTTP GET request

Domains Data API for Developers.
Host.io API is a free Development API that requires apiKey authentication, is served over HTTPS and supports CORS, so it can be called from the browser.
Details from host.io.

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Basic DNS query via HTTP GET request
The Host.io API is provided by host.io (host.io).
Yes. The Host.io API is listed in the Development 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 Host.io API uses apiKey authentication, so you need to register for credentials before making requests.
Yes. The Host.io API supports CORS, so front-end JavaScript can call it directly.
Yes. The Host.io API is served over HTTPS, so it's safe to use in production.