maximum length url in web

Is Google [^]broken at your place?
It gave me About 169,000,000 results in 0.48 seconds.

Short answer - de facto limit of 2000 characters

If you keep URLs under 2000 characters, they'll work in virtually any combination of client and server software.

Longer answer - first, the standards...

RFC 2616[^] (Hypertext Transfer Protocol HTTP/1.1) section 3.2.1 says

The HTTP protocol does not place any a priori limit on the length of
a URI. Servers MUST be able to handle the URI of any resource they serve, and SHOULD be able to handle URIs of unbounded length if they provide GET-based forms that could generate such URIs. A server SHOULD return 414 (Request-URI Too Long) status if a URI is longer than the server can handle (see section 10.4.15).