Can the Geolocation of an IP be Guessed?
No, there is not. Blocks are moved, sold and sometimes mobile. Most base data comes from WHOIS databases and RIR databases, which are public. Refined data based on user data is added by some parties to make it more accurate, for example, gps, cell and wifi networks often are fixed locations and are sometimes submitted to profiling and advertising services when you use apps on mobile devices or shop online. This is also why the data can sometimes be very inaccurate; a fixed internet connection might have an IP from a block that is listed with the address of a regional ISP office instead of the service area where that block is used. This data usually gets updated when an ISP sells or moves or devides a block and updates the WHOIS data.