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.

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IP to CIDR result

69.171.232.0/24

lower

69.171.232.0

upper

69.171.232.255

subnet

255.255.255.0

broadcast

69.171.232.255

count

256

useable

254

1								2								3								4
1-8								9-16								17-24								25-32
69								171								232								0
0	1	0	0	0	1	0	1	1	0	1	0	1	0	1	1	1	1	1	0	1	0	0	0	0	0	0	0	0	0	0	0
/24

Log

2 IP's parsed from input
Creating CIDR '69.171.232.0/24' based upon input '69.171.232.1' and '69.171.232.255'