192.168.0.1 is a part of the private c class IP range of 192.168.0.0 - 192.168.255.255, which are reserved for private use within internal networks. IP addresses like 192.168.0.1 are private and therefore cannot be used to surf internet. These private IP addresses are usually assigned by internal network devices such as routers to communicate between the Local Area Network (LAN). 192.168.0.1 is particularly used as a gateway or admin IP to log into router's admin panel such as NETGEAR, TP-Link, D-Link.
Since 192.168.0.1 is part of reserved private IP addresses. It is only available to internal users inside a network and therefore a physcial address cannot be assigned to a private IP address. Read this article to find difference between Public and Private IP address.
First of all, to be able to connect to router's admin panel you make sure that you are connected to the concerned router either through wirelessly or ethernet cable. Secondly, make sure that the default gateway or admin URL of the concerned router device is 192.168.0.1. Only then you are able to connect to the admin panel. Once you have everything in order please follow the steps below:
Rest assured that there is no need of an active internet connection to log into router's admin panel. Howerver, if you are not able to log into router's admin panel using above IP address then you may try 192.168.1.1, 192.168.1.254 or 10.0.0.1.
Not all router devices login page is set to 192.168.0.1. Router admin panel login IP address is preassigned by device manufecturer and each manufacturer of router device may set different gateway IP. The best place to find correct router login IP address is to check router label.
Normally username: admin and password: admin is used for almost all WiFi router devices. Howerver, if your router had a different password and you have forgotten it then you have two options left to recover the router admin password. These two options are:
192.168.0.1 is part of private C class range which is reserved for private networks. Therefore, the ranges are never assigned to any private organizations and can be used by anyone within their private networks. To check complete details you can also perform IP WHOIS Lookup.