Most Xiaomi routers use 192.168.31.1 as their default IP address. Many also answer at http://miwifi.com.
Every Known Xiaomi Default IP Address
| Xiaomi Model | IP Address |
| CB0401 | 192.168.31.1 |
| Mi Router 4A Giga | 192.168.31.1 |
| Mi Router AX1800 | 192.168.31.1 |
| Mi Router AX6000 | 192.168.31.1 |
| Mi Router AX9000 | 192.168.1.1 |
| Mi WiFi Router 3 | 192.168.31.1 |
Find Your Router's IP Address
Run ipconfig on Windows and read Default Gateway, or check Router in your WiFi network's details. See How To Find Your Router's IP Address.
Change the Router's IP Address
Log in, go to Settings > LAN settings, change the router's IP address, and save. Then log back in at the new address.