CIDR and subnet calculator

IP to CIDR - simple

Input lower and upper IP (either IPv4 or IPv6) of the range - the tool will calculate best matching CIDR range. Subnet will be included in result.



IP to CIDR - advanced

Input at least two IP's (IPv4 and/or IPv6), domainnames or CIDR ranges to include - the tool will calculate best matching CIDR ranges. Subnet will be included in result. Seperate by space, tab, newline or comma.


IPv4 max network prefix:

IPv6 max network prefix:

Reverse - CIDR to IP + subnet

Input one or more CIDR ranges to get info of IP addresses and subnet.


CIDR to IP result

2405:2000::/31


CIDR
2405:2000::/31

This CIDR range reference a lot of IP's - be cautious about using this, in a security context.

lower IP
2405:2000::


upper IP
2405:2001:ffff:ffff:ffff:ffff:ffff:ffff


subnet
ffff:fffe::


broadcast
2405:2001:ffff:ffff:ffff:ffff:ffff:ffff


count
1,6E+29



byte no: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
bit no:

 1-8

 9-16

 17-24

 25-32

 33-40

 41-48

 49-56

 57-64

 65-72

 73-80

 81-88

 89-96

 97-104

 105-112

 113-120

 121-128
value: 24 05 20 00 00 00 00 00 00 00 00 00 00 00 00 00
bit pattern:
0
0
1
0
0
1
0
0
0
0
0
0
0
1
0
1
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
prefix:
/31
 

Log

  • Parseing '2405:2000::/31' into 1,6E+29 IP's