Basic DNS query via HTTP GET request.
host-t.com API is a free Development API that requires no API key, is served over HTTPS and does not support CORS, so it should be called from a server.
Details from host-t.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.
The host-t.com API is provided by DNS via HTTP (host-t.com).
Yes. The host-t.com 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.
No. The host-t.com API requires no authentication, so you can start making requests without signing up.
Not directly. The host-t.com API does not allow CORS, so call it from a server, serverless function or proxy instead of front-end JavaScript.
Yes. The host-t.com API is served over HTTPS, so it's safe to use in production.