Your IP address:
Provider:
...

For example: 3.137.218.215

/
Input
Address: 18.208.0.0
Netmask: 255.248.0.0 = 13
Inversion mask: 0.7.255.255
Binary: 00010010.11010000.00000000.00000000
Reserved: No
Result
Network: 18.208.0.0/13 (Class A)
First IP: 18.208.0.1
Last IP: 18.215.255.254
Broadcast: 18.215.255.255
Network range: 18.208.0.0 - 18.215.255.255
Number of hosts: 524286
Number of IP addresses: 524288