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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Network85.64.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
85.64.0.0
Broadcast address
85.67.255.255
First usable
85.64.0.1
Last usable
85.67.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
A (default /8)
As numbers
Hex 55400000 · Integer 1430257664 to 1430519807
Reverse DNS zones
64.85.in-addr.arpa
65.85.in-addr.arpa
66.85.in-addr.arpa
67.85.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01010101.01000000.00000000.0000000085.64.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01010101.01000000.00000000.0000000085.64.0.0
Broadcast01010101.01000011.11111111.1111111185.67.255.255
Split into smaller subnets/22
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

85.64.0.0/14 makes 256 subnets of /22.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
185.64.0.0/2285.64.0.1 to 85.64.3.25485.64.3.2551,022
285.64.4.0/2285.64.4.1 to 85.64.7.25485.64.7.2551,022
385.64.8.0/2285.64.8.1 to 85.64.11.25485.64.11.2551,022
485.64.12.0/2285.64.12.1 to 85.64.15.25485.64.15.2551,022
585.64.16.0/2285.64.16.1 to 85.64.19.25485.64.19.2551,022
685.64.20.0/2285.64.20.1 to 85.64.23.25485.64.23.2551,022
785.64.24.0/2285.64.24.1 to 85.64.27.25485.64.27.2551,022
885.64.28.0/2285.64.28.1 to 85.64.31.25485.64.31.2551,022
985.64.32.0/2285.64.32.1 to 85.64.35.25485.64.35.2551,022
1085.64.36.0/2285.64.36.1 to 85.64.39.25485.64.39.2551,022
1185.64.40.0/2285.64.40.1 to 85.64.43.25485.64.43.2551,022
1285.64.44.0/2285.64.44.1 to 85.64.47.25485.64.47.2551,022
1385.64.48.0/2285.64.48.1 to 85.64.51.25485.64.51.2551,022
1485.64.52.0/2285.64.52.1 to 85.64.55.25485.64.55.2551,022
1585.64.56.0/2285.64.56.1 to 85.64.59.25485.64.59.2551,022
1685.64.60.0/2285.64.60.1 to 85.64.63.25485.64.63.2551,022
1785.64.64.0/2285.64.64.1 to 85.64.67.25485.64.67.2551,022
1885.64.68.0/2285.64.68.1 to 85.64.71.25485.64.71.2551,022
1985.64.72.0/2285.64.72.1 to 85.64.75.25485.64.75.2551,022
2085.64.76.0/2285.64.76.1 to 85.64.79.25485.64.79.2551,022
2185.64.80.0/2285.64.80.1 to 85.64.83.25485.64.83.2551,022
2285.64.84.0/2285.64.84.1 to 85.64.87.25485.64.87.2551,022
2385.64.88.0/2285.64.88.1 to 85.64.91.25485.64.91.2551,022
2485.64.92.0/2285.64.92.1 to 85.64.95.25485.64.95.2551,022
2585.64.96.0/2285.64.96.1 to 85.64.99.25485.64.99.2551,022
2685.64.100.0/2285.64.100.1 to 85.64.103.25485.64.103.2551,022
2785.64.104.0/2285.64.104.1 to 85.64.107.25485.64.107.2551,022
2885.64.108.0/2285.64.108.1 to 85.64.111.25485.64.111.2551,022
2985.64.112.0/2285.64.112.1 to 85.64.115.25485.64.115.2551,022
3085.64.116.0/2285.64.116.1 to 85.64.119.25485.64.119.2551,022
3185.64.120.0/2285.64.120.1 to 85.64.123.25485.64.123.2551,022
3285.64.124.0/2285.64.124.1 to 85.64.127.25485.64.127.2551,022
3385.64.128.0/2285.64.128.1 to 85.64.131.25485.64.131.2551,022
3485.64.132.0/2285.64.132.1 to 85.64.135.25485.64.135.2551,022
3585.64.136.0/2285.64.136.1 to 85.64.139.25485.64.139.2551,022
3685.64.140.0/2285.64.140.1 to 85.64.143.25485.64.143.2551,022
3785.64.144.0/2285.64.144.1 to 85.64.147.25485.64.147.2551,022
3885.64.148.0/2285.64.148.1 to 85.64.151.25485.64.151.2551,022
3985.64.152.0/2285.64.152.1 to 85.64.155.25485.64.155.2551,022
4085.64.156.0/2285.64.156.1 to 85.64.159.25485.64.159.2551,022
4185.64.160.0/2285.64.160.1 to 85.64.163.25485.64.163.2551,022
4285.64.164.0/2285.64.164.1 to 85.64.167.25485.64.167.2551,022
4385.64.168.0/2285.64.168.1 to 85.64.171.25485.64.171.2551,022
4485.64.172.0/2285.64.172.1 to 85.64.175.25485.64.175.2551,022
4585.64.176.0/2285.64.176.1 to 85.64.179.25485.64.179.2551,022
4685.64.180.0/2285.64.180.1 to 85.64.183.25485.64.183.2551,022
4785.64.184.0/2285.64.184.1 to 85.64.187.25485.64.187.2551,022
4885.64.188.0/2285.64.188.1 to 85.64.191.25485.64.191.2551,022
4985.64.192.0/2285.64.192.1 to 85.64.195.25485.64.195.2551,022
5085.64.196.0/2285.64.196.1 to 85.64.199.25485.64.199.2551,022
5185.64.200.0/2285.64.200.1 to 85.64.203.25485.64.203.2551,022
5285.64.204.0/2285.64.204.1 to 85.64.207.25485.64.207.2551,022
5385.64.208.0/2285.64.208.1 to 85.64.211.25485.64.211.2551,022
5485.64.212.0/2285.64.212.1 to 85.64.215.25485.64.215.2551,022
5585.64.216.0/2285.64.216.1 to 85.64.219.25485.64.219.2551,022
5685.64.220.0/2285.64.220.1 to 85.64.223.25485.64.223.2551,022
5785.64.224.0/2285.64.224.1 to 85.64.227.25485.64.227.2551,022
5885.64.228.0/2285.64.228.1 to 85.64.231.25485.64.231.2551,022
5985.64.232.0/2285.64.232.1 to 85.64.235.25485.64.235.2551,022
6085.64.236.0/2285.64.236.1 to 85.64.239.25485.64.239.2551,022
6185.64.240.0/2285.64.240.1 to 85.64.243.25485.64.243.2551,022
6285.64.244.0/2285.64.244.1 to 85.64.247.25485.64.247.2551,022
6385.64.248.0/2285.64.248.1 to 85.64.251.25485.64.251.2551,022
6485.64.252.0/2285.64.252.1 to 85.64.255.25485.64.255.2551,022
6585.65.0.0/2285.65.0.1 to 85.65.3.25485.65.3.2551,022
6685.65.4.0/2285.65.4.1 to 85.65.7.25485.65.7.2551,022
6785.65.8.0/2285.65.8.1 to 85.65.11.25485.65.11.2551,022
6885.65.12.0/2285.65.12.1 to 85.65.15.25485.65.15.2551,022
6985.65.16.0/2285.65.16.1 to 85.65.19.25485.65.19.2551,022
7085.65.20.0/2285.65.20.1 to 85.65.23.25485.65.23.2551,022
7185.65.24.0/2285.65.24.1 to 85.65.27.25485.65.27.2551,022
7285.65.28.0/2285.65.28.1 to 85.65.31.25485.65.31.2551,022
7385.65.32.0/2285.65.32.1 to 85.65.35.25485.65.35.2551,022
7485.65.36.0/2285.65.36.1 to 85.65.39.25485.65.39.2551,022
7585.65.40.0/2285.65.40.1 to 85.65.43.25485.65.43.2551,022
7685.65.44.0/2285.65.44.1 to 85.65.47.25485.65.47.2551,022
7785.65.48.0/2285.65.48.1 to 85.65.51.25485.65.51.2551,022
7885.65.52.0/2285.65.52.1 to 85.65.55.25485.65.55.2551,022
7985.65.56.0/2285.65.56.1 to 85.65.59.25485.65.59.2551,022
8085.65.60.0/2285.65.60.1 to 85.65.63.25485.65.63.2551,022
8185.65.64.0/2285.65.64.1 to 85.65.67.25485.65.67.2551,022
8285.65.68.0/2285.65.68.1 to 85.65.71.25485.65.71.2551,022
8385.65.72.0/2285.65.72.1 to 85.65.75.25485.65.75.2551,022
8485.65.76.0/2285.65.76.1 to 85.65.79.25485.65.79.2551,022
8585.65.80.0/2285.65.80.1 to 85.65.83.25485.65.83.2551,022
8685.65.84.0/2285.65.84.1 to 85.65.87.25485.65.87.2551,022
8785.65.88.0/2285.65.88.1 to 85.65.91.25485.65.91.2551,022
8885.65.92.0/2285.65.92.1 to 85.65.95.25485.65.95.2551,022
8985.65.96.0/2285.65.96.1 to 85.65.99.25485.65.99.2551,022
9085.65.100.0/2285.65.100.1 to 85.65.103.25485.65.103.2551,022
9185.65.104.0/2285.65.104.1 to 85.65.107.25485.65.107.2551,022
9285.65.108.0/2285.65.108.1 to 85.65.111.25485.65.111.2551,022
9385.65.112.0/2285.65.112.1 to 85.65.115.25485.65.115.2551,022
9485.65.116.0/2285.65.116.1 to 85.65.119.25485.65.119.2551,022
9585.65.120.0/2285.65.120.1 to 85.65.123.25485.65.123.2551,022
9685.65.124.0/2285.65.124.1 to 85.65.127.25485.65.127.2551,022
9785.65.128.0/2285.65.128.1 to 85.65.131.25485.65.131.2551,022
9885.65.132.0/2285.65.132.1 to 85.65.135.25485.65.135.2551,022
9985.65.136.0/2285.65.136.1 to 85.65.139.25485.65.139.2551,022
10085.65.140.0/2285.65.140.1 to 85.65.143.25485.65.143.2551,022
10185.65.144.0/2285.65.144.1 to 85.65.147.25485.65.147.2551,022
10285.65.148.0/2285.65.148.1 to 85.65.151.25485.65.151.2551,022
10385.65.152.0/2285.65.152.1 to 85.65.155.25485.65.155.2551,022
10485.65.156.0/2285.65.156.1 to 85.65.159.25485.65.159.2551,022
10585.65.160.0/2285.65.160.1 to 85.65.163.25485.65.163.2551,022
10685.65.164.0/2285.65.164.1 to 85.65.167.25485.65.167.2551,022
10785.65.168.0/2285.65.168.1 to 85.65.171.25485.65.171.2551,022
10885.65.172.0/2285.65.172.1 to 85.65.175.25485.65.175.2551,022
10985.65.176.0/2285.65.176.1 to 85.65.179.25485.65.179.2551,022
11085.65.180.0/2285.65.180.1 to 85.65.183.25485.65.183.2551,022
11185.65.184.0/2285.65.184.1 to 85.65.187.25485.65.187.2551,022
11285.65.188.0/2285.65.188.1 to 85.65.191.25485.65.191.2551,022
11385.65.192.0/2285.65.192.1 to 85.65.195.25485.65.195.2551,022
11485.65.196.0/2285.65.196.1 to 85.65.199.25485.65.199.2551,022
11585.65.200.0/2285.65.200.1 to 85.65.203.25485.65.203.2551,022
11685.65.204.0/2285.65.204.1 to 85.65.207.25485.65.207.2551,022
11785.65.208.0/2285.65.208.1 to 85.65.211.25485.65.211.2551,022
11885.65.212.0/2285.65.212.1 to 85.65.215.25485.65.215.2551,022
11985.65.216.0/2285.65.216.1 to 85.65.219.25485.65.219.2551,022
12085.65.220.0/2285.65.220.1 to 85.65.223.25485.65.223.2551,022
12185.65.224.0/2285.65.224.1 to 85.65.227.25485.65.227.2551,022
12285.65.228.0/2285.65.228.1 to 85.65.231.25485.65.231.2551,022
12385.65.232.0/2285.65.232.1 to 85.65.235.25485.65.235.2551,022
12485.65.236.0/2285.65.236.1 to 85.65.239.25485.65.239.2551,022
12585.65.240.0/2285.65.240.1 to 85.65.243.25485.65.243.2551,022
12685.65.244.0/2285.65.244.1 to 85.65.247.25485.65.247.2551,022
12785.65.248.0/2285.65.248.1 to 85.65.251.25485.65.251.2551,022
12885.65.252.0/2285.65.252.1 to 85.65.255.25485.65.255.2551,022
12985.66.0.0/2285.66.0.1 to 85.66.3.25485.66.3.2551,022
13085.66.4.0/2285.66.4.1 to 85.66.7.25485.66.7.2551,022
13185.66.8.0/2285.66.8.1 to 85.66.11.25485.66.11.2551,022
13285.66.12.0/2285.66.12.1 to 85.66.15.25485.66.15.2551,022
13385.66.16.0/2285.66.16.1 to 85.66.19.25485.66.19.2551,022
13485.66.20.0/2285.66.20.1 to 85.66.23.25485.66.23.2551,022
13585.66.24.0/2285.66.24.1 to 85.66.27.25485.66.27.2551,022
13685.66.28.0/2285.66.28.1 to 85.66.31.25485.66.31.2551,022
13785.66.32.0/2285.66.32.1 to 85.66.35.25485.66.35.2551,022
13885.66.36.0/2285.66.36.1 to 85.66.39.25485.66.39.2551,022
13985.66.40.0/2285.66.40.1 to 85.66.43.25485.66.43.2551,022
14085.66.44.0/2285.66.44.1 to 85.66.47.25485.66.47.2551,022
14185.66.48.0/2285.66.48.1 to 85.66.51.25485.66.51.2551,022
14285.66.52.0/2285.66.52.1 to 85.66.55.25485.66.55.2551,022
14385.66.56.0/2285.66.56.1 to 85.66.59.25485.66.59.2551,022
14485.66.60.0/2285.66.60.1 to 85.66.63.25485.66.63.2551,022
14585.66.64.0/2285.66.64.1 to 85.66.67.25485.66.67.2551,022
14685.66.68.0/2285.66.68.1 to 85.66.71.25485.66.71.2551,022
14785.66.72.0/2285.66.72.1 to 85.66.75.25485.66.75.2551,022
14885.66.76.0/2285.66.76.1 to 85.66.79.25485.66.79.2551,022
14985.66.80.0/2285.66.80.1 to 85.66.83.25485.66.83.2551,022
15085.66.84.0/2285.66.84.1 to 85.66.87.25485.66.87.2551,022
15185.66.88.0/2285.66.88.1 to 85.66.91.25485.66.91.2551,022
15285.66.92.0/2285.66.92.1 to 85.66.95.25485.66.95.2551,022
15385.66.96.0/2285.66.96.1 to 85.66.99.25485.66.99.2551,022
15485.66.100.0/2285.66.100.1 to 85.66.103.25485.66.103.2551,022
15585.66.104.0/2285.66.104.1 to 85.66.107.25485.66.107.2551,022
15685.66.108.0/2285.66.108.1 to 85.66.111.25485.66.111.2551,022
15785.66.112.0/2285.66.112.1 to 85.66.115.25485.66.115.2551,022
15885.66.116.0/2285.66.116.1 to 85.66.119.25485.66.119.2551,022
15985.66.120.0/2285.66.120.1 to 85.66.123.25485.66.123.2551,022
16085.66.124.0/2285.66.124.1 to 85.66.127.25485.66.127.2551,022
16185.66.128.0/2285.66.128.1 to 85.66.131.25485.66.131.2551,022
16285.66.132.0/2285.66.132.1 to 85.66.135.25485.66.135.2551,022
16385.66.136.0/2285.66.136.1 to 85.66.139.25485.66.139.2551,022
16485.66.140.0/2285.66.140.1 to 85.66.143.25485.66.143.2551,022
16585.66.144.0/2285.66.144.1 to 85.66.147.25485.66.147.2551,022
16685.66.148.0/2285.66.148.1 to 85.66.151.25485.66.151.2551,022
16785.66.152.0/2285.66.152.1 to 85.66.155.25485.66.155.2551,022
16885.66.156.0/2285.66.156.1 to 85.66.159.25485.66.159.2551,022
16985.66.160.0/2285.66.160.1 to 85.66.163.25485.66.163.2551,022
17085.66.164.0/2285.66.164.1 to 85.66.167.25485.66.167.2551,022
17185.66.168.0/2285.66.168.1 to 85.66.171.25485.66.171.2551,022
17285.66.172.0/2285.66.172.1 to 85.66.175.25485.66.175.2551,022
17385.66.176.0/2285.66.176.1 to 85.66.179.25485.66.179.2551,022
17485.66.180.0/2285.66.180.1 to 85.66.183.25485.66.183.2551,022
17585.66.184.0/2285.66.184.1 to 85.66.187.25485.66.187.2551,022
17685.66.188.0/2285.66.188.1 to 85.66.191.25485.66.191.2551,022
17785.66.192.0/2285.66.192.1 to 85.66.195.25485.66.195.2551,022
17885.66.196.0/2285.66.196.1 to 85.66.199.25485.66.199.2551,022
17985.66.200.0/2285.66.200.1 to 85.66.203.25485.66.203.2551,022
18085.66.204.0/2285.66.204.1 to 85.66.207.25485.66.207.2551,022
18185.66.208.0/2285.66.208.1 to 85.66.211.25485.66.211.2551,022
18285.66.212.0/2285.66.212.1 to 85.66.215.25485.66.215.2551,022
18385.66.216.0/2285.66.216.1 to 85.66.219.25485.66.219.2551,022
18485.66.220.0/2285.66.220.1 to 85.66.223.25485.66.223.2551,022
18585.66.224.0/2285.66.224.1 to 85.66.227.25485.66.227.2551,022
18685.66.228.0/2285.66.228.1 to 85.66.231.25485.66.231.2551,022
18785.66.232.0/2285.66.232.1 to 85.66.235.25485.66.235.2551,022
18885.66.236.0/2285.66.236.1 to 85.66.239.25485.66.239.2551,022
18985.66.240.0/2285.66.240.1 to 85.66.243.25485.66.243.2551,022
19085.66.244.0/2285.66.244.1 to 85.66.247.25485.66.247.2551,022
19185.66.248.0/2285.66.248.1 to 85.66.251.25485.66.251.2551,022
19285.66.252.0/2285.66.252.1 to 85.66.255.25485.66.255.2551,022
19385.67.0.0/2285.67.0.1 to 85.67.3.25485.67.3.2551,022
19485.67.4.0/2285.67.4.1 to 85.67.7.25485.67.7.2551,022
19585.67.8.0/2285.67.8.1 to 85.67.11.25485.67.11.2551,022
19685.67.12.0/2285.67.12.1 to 85.67.15.25485.67.15.2551,022
19785.67.16.0/2285.67.16.1 to 85.67.19.25485.67.19.2551,022
19885.67.20.0/2285.67.20.1 to 85.67.23.25485.67.23.2551,022
19985.67.24.0/2285.67.24.1 to 85.67.27.25485.67.27.2551,022
20085.67.28.0/2285.67.28.1 to 85.67.31.25485.67.31.2551,022
20185.67.32.0/2285.67.32.1 to 85.67.35.25485.67.35.2551,022
20285.67.36.0/2285.67.36.1 to 85.67.39.25485.67.39.2551,022
20385.67.40.0/2285.67.40.1 to 85.67.43.25485.67.43.2551,022
20485.67.44.0/2285.67.44.1 to 85.67.47.25485.67.47.2551,022
20585.67.48.0/2285.67.48.1 to 85.67.51.25485.67.51.2551,022
20685.67.52.0/2285.67.52.1 to 85.67.55.25485.67.55.2551,022
20785.67.56.0/2285.67.56.1 to 85.67.59.25485.67.59.2551,022
20885.67.60.0/2285.67.60.1 to 85.67.63.25485.67.63.2551,022
20985.67.64.0/2285.67.64.1 to 85.67.67.25485.67.67.2551,022
21085.67.68.0/2285.67.68.1 to 85.67.71.25485.67.71.2551,022
21185.67.72.0/2285.67.72.1 to 85.67.75.25485.67.75.2551,022
21285.67.76.0/2285.67.76.1 to 85.67.79.25485.67.79.2551,022
21385.67.80.0/2285.67.80.1 to 85.67.83.25485.67.83.2551,022
21485.67.84.0/2285.67.84.1 to 85.67.87.25485.67.87.2551,022
21585.67.88.0/2285.67.88.1 to 85.67.91.25485.67.91.2551,022
21685.67.92.0/2285.67.92.1 to 85.67.95.25485.67.95.2551,022
21785.67.96.0/2285.67.96.1 to 85.67.99.25485.67.99.2551,022
21885.67.100.0/2285.67.100.1 to 85.67.103.25485.67.103.2551,022
21985.67.104.0/2285.67.104.1 to 85.67.107.25485.67.107.2551,022
22085.67.108.0/2285.67.108.1 to 85.67.111.25485.67.111.2551,022
22185.67.112.0/2285.67.112.1 to 85.67.115.25485.67.115.2551,022
22285.67.116.0/2285.67.116.1 to 85.67.119.25485.67.119.2551,022
22385.67.120.0/2285.67.120.1 to 85.67.123.25485.67.123.2551,022
22485.67.124.0/2285.67.124.1 to 85.67.127.25485.67.127.2551,022
22585.67.128.0/2285.67.128.1 to 85.67.131.25485.67.131.2551,022
22685.67.132.0/2285.67.132.1 to 85.67.135.25485.67.135.2551,022
22785.67.136.0/2285.67.136.1 to 85.67.139.25485.67.139.2551,022
22885.67.140.0/2285.67.140.1 to 85.67.143.25485.67.143.2551,022
22985.67.144.0/2285.67.144.1 to 85.67.147.25485.67.147.2551,022
23085.67.148.0/2285.67.148.1 to 85.67.151.25485.67.151.2551,022
23185.67.152.0/2285.67.152.1 to 85.67.155.25485.67.155.2551,022
23285.67.156.0/2285.67.156.1 to 85.67.159.25485.67.159.2551,022
23385.67.160.0/2285.67.160.1 to 85.67.163.25485.67.163.2551,022
23485.67.164.0/2285.67.164.1 to 85.67.167.25485.67.167.2551,022
23585.67.168.0/2285.67.168.1 to 85.67.171.25485.67.171.2551,022
23685.67.172.0/2285.67.172.1 to 85.67.175.25485.67.175.2551,022
23785.67.176.0/2285.67.176.1 to 85.67.179.25485.67.179.2551,022
23885.67.180.0/2285.67.180.1 to 85.67.183.25485.67.183.2551,022
23985.67.184.0/2285.67.184.1 to 85.67.187.25485.67.187.2551,022
24085.67.188.0/2285.67.188.1 to 85.67.191.25485.67.191.2551,022
24185.67.192.0/2285.67.192.1 to 85.67.195.25485.67.195.2551,022
24285.67.196.0/2285.67.196.1 to 85.67.199.25485.67.199.2551,022
24385.67.200.0/2285.67.200.1 to 85.67.203.25485.67.203.2551,022
24485.67.204.0/2285.67.204.1 to 85.67.207.25485.67.207.2551,022
24585.67.208.0/2285.67.208.1 to 85.67.211.25485.67.211.2551,022
24685.67.212.0/2285.67.212.1 to 85.67.215.25485.67.215.2551,022
24785.67.216.0/2285.67.216.1 to 85.67.219.25485.67.219.2551,022
24885.67.220.0/2285.67.220.1 to 85.67.223.25485.67.223.2551,022
24985.67.224.0/2285.67.224.1 to 85.67.227.25485.67.227.2551,022
25085.67.228.0/2285.67.228.1 to 85.67.231.25485.67.231.2551,022
25185.67.232.0/2285.67.232.1 to 85.67.235.25485.67.235.2551,022
25285.67.236.0/2285.67.236.1 to 85.67.239.25485.67.239.2551,022
25385.67.240.0/2285.67.240.1 to 85.67.243.25485.67.243.2551,022
25485.67.244.0/2285.67.244.1 to 85.67.247.25485.67.247.2551,022
25585.67.248.0/2285.67.248.1 to 85.67.251.25485.67.251.2551,022
25685.67.252.0/2285.67.252.1 to 85.67.255.25485.67.255.2551,022

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.