How to clear the local DNS cache in Mac operating system?

Step 1: Choose ‘Applications’, click ‘Utilities’, and find ‘Terminal’

Step 2: Enter the following command based on your Mac OS version

For 'El Capitan' to 'Mojave' versions: 
    sudo killall -HUP mDNSResponder

For 'Big Sur' versions: sudo dscacheutil -flushcache; 
            sudo killall -HUP mDNSResponder

Step 3: After these commands we might be asked for Mac Password, enter it.