How Can I Perform a DNS Lookup from Client-Side JavaScript?

DNS Lookup in Client-Side JavaScript

Performing a DNS lookup from the client-side using JavaScript has its limitations due to browser security restrictions. Pure JavaScript does not allow direct access to the underlying operating system's DNS resolution capabilities.

However, there are workarounds to achieve this functionality. One approach involves utilizing a server-side proxy that acts as a middleman between the client and the DNS server.

Another method, as suggested in the given answer, leverages JSONP (JSON with Padding) to obtain the client's IP address from a remote web service. This approach involves creating a callback function on the client side and sending an HTTP request to a JSONP endpoint that returns the client's IP address wrapped in a JSON object.

This workaround allows the client to access the server-side information without directly querying the DNS server from the client's machine. However, it requires the use of a third-party service and may not be optimal for all scenarios.

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