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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.

Network88.0.0.0/5
Usable hosts134,217,726
Subnet mask248.0.0.0
Addresses134,217,728
Network address
88.0.0.0
Broadcast address
95.255.255.255
First usable
88.0.0.1
Last usable
95.255.255.254
Usable hosts
134,217,726 (134,217,728 less the network and broadcast addresses)
Subnet mask
248.0.0.0
Wildcard mask
7.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/5
Type
Public public
Old class
A (default /8)
As numbers
Hex 58000000 · Integer 1476395008 to 1610612735
Reverse DNS zones
88.in-addr.arpa
89.in-addr.arpa
90.in-addr.arpa
91.in-addr.arpa
92.in-addr.arpa
93.in-addr.arpa
94.in-addr.arpa
95.in-addr.arpa
/5 is not on a 8-bit boundary, so it takes 8 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011000.00000000.00000000.0000000088.0.0.0
Subnet mask11111000.00000000.00000000.00000000248.0.0.0
Network01011000.00000000.00000000.0000000088.0.0.0
Broadcast01011111.11111111.11111111.1111111195.255.255.255
Split into smaller subnets/13
/6 (2)/7 (4)/8 (8)/9 (16)/10 (32)/11 (64)/12 (128)/13 (256)/14 (512)/15 (1,024)/16 (2,048)/17 (4,096)

88.0.0.0/5 makes 256 subnets of /13.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
188.0.0.0/1388.0.0.1 to 88.7.255.25488.7.255.255524,286
288.8.0.0/1388.8.0.1 to 88.15.255.25488.15.255.255524,286
388.16.0.0/1388.16.0.1 to 88.23.255.25488.23.255.255524,286
488.24.0.0/1388.24.0.1 to 88.31.255.25488.31.255.255524,286
588.32.0.0/1388.32.0.1 to 88.39.255.25488.39.255.255524,286
688.40.0.0/1388.40.0.1 to 88.47.255.25488.47.255.255524,286
788.48.0.0/1388.48.0.1 to 88.55.255.25488.55.255.255524,286
888.56.0.0/1388.56.0.1 to 88.63.255.25488.63.255.255524,286
988.64.0.0/1388.64.0.1 to 88.71.255.25488.71.255.255524,286
1088.72.0.0/1388.72.0.1 to 88.79.255.25488.79.255.255524,286
1188.80.0.0/1388.80.0.1 to 88.87.255.25488.87.255.255524,286
1288.88.0.0/1388.88.0.1 to 88.95.255.25488.95.255.255524,286
1388.96.0.0/1388.96.0.1 to 88.103.255.25488.103.255.255524,286
1488.104.0.0/1388.104.0.1 to 88.111.255.25488.111.255.255524,286
1588.112.0.0/1388.112.0.1 to 88.119.255.25488.119.255.255524,286
1688.120.0.0/1388.120.0.1 to 88.127.255.25488.127.255.255524,286
1788.128.0.0/1388.128.0.1 to 88.135.255.25488.135.255.255524,286
1888.136.0.0/1388.136.0.1 to 88.143.255.25488.143.255.255524,286
1988.144.0.0/1388.144.0.1 to 88.151.255.25488.151.255.255524,286
2088.152.0.0/1388.152.0.1 to 88.159.255.25488.159.255.255524,286
2188.160.0.0/1388.160.0.1 to 88.167.255.25488.167.255.255524,286
2288.168.0.0/1388.168.0.1 to 88.175.255.25488.175.255.255524,286
2388.176.0.0/1388.176.0.1 to 88.183.255.25488.183.255.255524,286
2488.184.0.0/1388.184.0.1 to 88.191.255.25488.191.255.255524,286
2588.192.0.0/1388.192.0.1 to 88.199.255.25488.199.255.255524,286
2688.200.0.0/1388.200.0.1 to 88.207.255.25488.207.255.255524,286
2788.208.0.0/1388.208.0.1 to 88.215.255.25488.215.255.255524,286
2888.216.0.0/1388.216.0.1 to 88.223.255.25488.223.255.255524,286
2988.224.0.0/1388.224.0.1 to 88.231.255.25488.231.255.255524,286
3088.232.0.0/1388.232.0.1 to 88.239.255.25488.239.255.255524,286
3188.240.0.0/1388.240.0.1 to 88.247.255.25488.247.255.255524,286
3288.248.0.0/1388.248.0.1 to 88.255.255.25488.255.255.255524,286
3389.0.0.0/1389.0.0.1 to 89.7.255.25489.7.255.255524,286
3489.8.0.0/1389.8.0.1 to 89.15.255.25489.15.255.255524,286
3589.16.0.0/1389.16.0.1 to 89.23.255.25489.23.255.255524,286
3689.24.0.0/1389.24.0.1 to 89.31.255.25489.31.255.255524,286
3789.32.0.0/1389.32.0.1 to 89.39.255.25489.39.255.255524,286
3889.40.0.0/1389.40.0.1 to 89.47.255.25489.47.255.255524,286
3989.48.0.0/1389.48.0.1 to 89.55.255.25489.55.255.255524,286
4089.56.0.0/1389.56.0.1 to 89.63.255.25489.63.255.255524,286
4189.64.0.0/1389.64.0.1 to 89.71.255.25489.71.255.255524,286
4289.72.0.0/1389.72.0.1 to 89.79.255.25489.79.255.255524,286
4389.80.0.0/1389.80.0.1 to 89.87.255.25489.87.255.255524,286
4489.88.0.0/1389.88.0.1 to 89.95.255.25489.95.255.255524,286
4589.96.0.0/1389.96.0.1 to 89.103.255.25489.103.255.255524,286
4689.104.0.0/1389.104.0.1 to 89.111.255.25489.111.255.255524,286
4789.112.0.0/1389.112.0.1 to 89.119.255.25489.119.255.255524,286
4889.120.0.0/1389.120.0.1 to 89.127.255.25489.127.255.255524,286
4989.128.0.0/1389.128.0.1 to 89.135.255.25489.135.255.255524,286
5089.136.0.0/1389.136.0.1 to 89.143.255.25489.143.255.255524,286
5189.144.0.0/1389.144.0.1 to 89.151.255.25489.151.255.255524,286
5289.152.0.0/1389.152.0.1 to 89.159.255.25489.159.255.255524,286
5389.160.0.0/1389.160.0.1 to 89.167.255.25489.167.255.255524,286
5489.168.0.0/1389.168.0.1 to 89.175.255.25489.175.255.255524,286
5589.176.0.0/1389.176.0.1 to 89.183.255.25489.183.255.255524,286
5689.184.0.0/1389.184.0.1 to 89.191.255.25489.191.255.255524,286
5789.192.0.0/1389.192.0.1 to 89.199.255.25489.199.255.255524,286
5889.200.0.0/1389.200.0.1 to 89.207.255.25489.207.255.255524,286
5989.208.0.0/1389.208.0.1 to 89.215.255.25489.215.255.255524,286
6089.216.0.0/1389.216.0.1 to 89.223.255.25489.223.255.255524,286
6189.224.0.0/1389.224.0.1 to 89.231.255.25489.231.255.255524,286
6289.232.0.0/1389.232.0.1 to 89.239.255.25489.239.255.255524,286
6389.240.0.0/1389.240.0.1 to 89.247.255.25489.247.255.255524,286
6489.248.0.0/1389.248.0.1 to 89.255.255.25489.255.255.255524,286
6590.0.0.0/1390.0.0.1 to 90.7.255.25490.7.255.255524,286
6690.8.0.0/1390.8.0.1 to 90.15.255.25490.15.255.255524,286
6790.16.0.0/1390.16.0.1 to 90.23.255.25490.23.255.255524,286
6890.24.0.0/1390.24.0.1 to 90.31.255.25490.31.255.255524,286
6990.32.0.0/1390.32.0.1 to 90.39.255.25490.39.255.255524,286
7090.40.0.0/1390.40.0.1 to 90.47.255.25490.47.255.255524,286
7190.48.0.0/1390.48.0.1 to 90.55.255.25490.55.255.255524,286
7290.56.0.0/1390.56.0.1 to 90.63.255.25490.63.255.255524,286
7390.64.0.0/1390.64.0.1 to 90.71.255.25490.71.255.255524,286
7490.72.0.0/1390.72.0.1 to 90.79.255.25490.79.255.255524,286
7590.80.0.0/1390.80.0.1 to 90.87.255.25490.87.255.255524,286
7690.88.0.0/1390.88.0.1 to 90.95.255.25490.95.255.255524,286
7790.96.0.0/1390.96.0.1 to 90.103.255.25490.103.255.255524,286
7890.104.0.0/1390.104.0.1 to 90.111.255.25490.111.255.255524,286
7990.112.0.0/1390.112.0.1 to 90.119.255.25490.119.255.255524,286
8090.120.0.0/1390.120.0.1 to 90.127.255.25490.127.255.255524,286
8190.128.0.0/1390.128.0.1 to 90.135.255.25490.135.255.255524,286
8290.136.0.0/1390.136.0.1 to 90.143.255.25490.143.255.255524,286
8390.144.0.0/1390.144.0.1 to 90.151.255.25490.151.255.255524,286
8490.152.0.0/1390.152.0.1 to 90.159.255.25490.159.255.255524,286
8590.160.0.0/1390.160.0.1 to 90.167.255.25490.167.255.255524,286
8690.168.0.0/1390.168.0.1 to 90.175.255.25490.175.255.255524,286
8790.176.0.0/1390.176.0.1 to 90.183.255.25490.183.255.255524,286
8890.184.0.0/1390.184.0.1 to 90.191.255.25490.191.255.255524,286
8990.192.0.0/1390.192.0.1 to 90.199.255.25490.199.255.255524,286
9090.200.0.0/1390.200.0.1 to 90.207.255.25490.207.255.255524,286
9190.208.0.0/1390.208.0.1 to 90.215.255.25490.215.255.255524,286
9290.216.0.0/1390.216.0.1 to 90.223.255.25490.223.255.255524,286
9390.224.0.0/1390.224.0.1 to 90.231.255.25490.231.255.255524,286
9490.232.0.0/1390.232.0.1 to 90.239.255.25490.239.255.255524,286
9590.240.0.0/1390.240.0.1 to 90.247.255.25490.247.255.255524,286
9690.248.0.0/1390.248.0.1 to 90.255.255.25490.255.255.255524,286
9791.0.0.0/1391.0.0.1 to 91.7.255.25491.7.255.255524,286
9891.8.0.0/1391.8.0.1 to 91.15.255.25491.15.255.255524,286
9991.16.0.0/1391.16.0.1 to 91.23.255.25491.23.255.255524,286
10091.24.0.0/1391.24.0.1 to 91.31.255.25491.31.255.255524,286
10191.32.0.0/1391.32.0.1 to 91.39.255.25491.39.255.255524,286
10291.40.0.0/1391.40.0.1 to 91.47.255.25491.47.255.255524,286
10391.48.0.0/1391.48.0.1 to 91.55.255.25491.55.255.255524,286
10491.56.0.0/1391.56.0.1 to 91.63.255.25491.63.255.255524,286
10591.64.0.0/1391.64.0.1 to 91.71.255.25491.71.255.255524,286
10691.72.0.0/1391.72.0.1 to 91.79.255.25491.79.255.255524,286
10791.80.0.0/1391.80.0.1 to 91.87.255.25491.87.255.255524,286
10891.88.0.0/1391.88.0.1 to 91.95.255.25491.95.255.255524,286
10991.96.0.0/1391.96.0.1 to 91.103.255.25491.103.255.255524,286
11091.104.0.0/1391.104.0.1 to 91.111.255.25491.111.255.255524,286
11191.112.0.0/1391.112.0.1 to 91.119.255.25491.119.255.255524,286
11291.120.0.0/1391.120.0.1 to 91.127.255.25491.127.255.255524,286
11391.128.0.0/1391.128.0.1 to 91.135.255.25491.135.255.255524,286
11491.136.0.0/1391.136.0.1 to 91.143.255.25491.143.255.255524,286
11591.144.0.0/1391.144.0.1 to 91.151.255.25491.151.255.255524,286
11691.152.0.0/1391.152.0.1 to 91.159.255.25491.159.255.255524,286
11791.160.0.0/1391.160.0.1 to 91.167.255.25491.167.255.255524,286
11891.168.0.0/1391.168.0.1 to 91.175.255.25491.175.255.255524,286
11991.176.0.0/1391.176.0.1 to 91.183.255.25491.183.255.255524,286
12091.184.0.0/1391.184.0.1 to 91.191.255.25491.191.255.255524,286
12191.192.0.0/1391.192.0.1 to 91.199.255.25491.199.255.255524,286
12291.200.0.0/1391.200.0.1 to 91.207.255.25491.207.255.255524,286
12391.208.0.0/1391.208.0.1 to 91.215.255.25491.215.255.255524,286
12491.216.0.0/1391.216.0.1 to 91.223.255.25491.223.255.255524,286
12591.224.0.0/1391.224.0.1 to 91.231.255.25491.231.255.255524,286
12691.232.0.0/1391.232.0.1 to 91.239.255.25491.239.255.255524,286
12791.240.0.0/1391.240.0.1 to 91.247.255.25491.247.255.255524,286
12891.248.0.0/1391.248.0.1 to 91.255.255.25491.255.255.255524,286
12992.0.0.0/1392.0.0.1 to 92.7.255.25492.7.255.255524,286
13092.8.0.0/1392.8.0.1 to 92.15.255.25492.15.255.255524,286
13192.16.0.0/1392.16.0.1 to 92.23.255.25492.23.255.255524,286
13292.24.0.0/1392.24.0.1 to 92.31.255.25492.31.255.255524,286
13392.32.0.0/1392.32.0.1 to 92.39.255.25492.39.255.255524,286
13492.40.0.0/1392.40.0.1 to 92.47.255.25492.47.255.255524,286
13592.48.0.0/1392.48.0.1 to 92.55.255.25492.55.255.255524,286
13692.56.0.0/1392.56.0.1 to 92.63.255.25492.63.255.255524,286
13792.64.0.0/1392.64.0.1 to 92.71.255.25492.71.255.255524,286
13892.72.0.0/1392.72.0.1 to 92.79.255.25492.79.255.255524,286
13992.80.0.0/1392.80.0.1 to 92.87.255.25492.87.255.255524,286
14092.88.0.0/1392.88.0.1 to 92.95.255.25492.95.255.255524,286
14192.96.0.0/1392.96.0.1 to 92.103.255.25492.103.255.255524,286
14292.104.0.0/1392.104.0.1 to 92.111.255.25492.111.255.255524,286
14392.112.0.0/1392.112.0.1 to 92.119.255.25492.119.255.255524,286
14492.120.0.0/1392.120.0.1 to 92.127.255.25492.127.255.255524,286
14592.128.0.0/1392.128.0.1 to 92.135.255.25492.135.255.255524,286
14692.136.0.0/1392.136.0.1 to 92.143.255.25492.143.255.255524,286
14792.144.0.0/1392.144.0.1 to 92.151.255.25492.151.255.255524,286
14892.152.0.0/1392.152.0.1 to 92.159.255.25492.159.255.255524,286
14992.160.0.0/1392.160.0.1 to 92.167.255.25492.167.255.255524,286
15092.168.0.0/1392.168.0.1 to 92.175.255.25492.175.255.255524,286
15192.176.0.0/1392.176.0.1 to 92.183.255.25492.183.255.255524,286
15292.184.0.0/1392.184.0.1 to 92.191.255.25492.191.255.255524,286
15392.192.0.0/1392.192.0.1 to 92.199.255.25492.199.255.255524,286
15492.200.0.0/1392.200.0.1 to 92.207.255.25492.207.255.255524,286
15592.208.0.0/1392.208.0.1 to 92.215.255.25492.215.255.255524,286
15692.216.0.0/1392.216.0.1 to 92.223.255.25492.223.255.255524,286
15792.224.0.0/1392.224.0.1 to 92.231.255.25492.231.255.255524,286
15892.232.0.0/1392.232.0.1 to 92.239.255.25492.239.255.255524,286
15992.240.0.0/1392.240.0.1 to 92.247.255.25492.247.255.255524,286
16092.248.0.0/1392.248.0.1 to 92.255.255.25492.255.255.255524,286
16193.0.0.0/1393.0.0.1 to 93.7.255.25493.7.255.255524,286
16293.8.0.0/1393.8.0.1 to 93.15.255.25493.15.255.255524,286
16393.16.0.0/1393.16.0.1 to 93.23.255.25493.23.255.255524,286
16493.24.0.0/1393.24.0.1 to 93.31.255.25493.31.255.255524,286
16593.32.0.0/1393.32.0.1 to 93.39.255.25493.39.255.255524,286
16693.40.0.0/1393.40.0.1 to 93.47.255.25493.47.255.255524,286
16793.48.0.0/1393.48.0.1 to 93.55.255.25493.55.255.255524,286
16893.56.0.0/1393.56.0.1 to 93.63.255.25493.63.255.255524,286
16993.64.0.0/1393.64.0.1 to 93.71.255.25493.71.255.255524,286
17093.72.0.0/1393.72.0.1 to 93.79.255.25493.79.255.255524,286
17193.80.0.0/1393.80.0.1 to 93.87.255.25493.87.255.255524,286
17293.88.0.0/1393.88.0.1 to 93.95.255.25493.95.255.255524,286
17393.96.0.0/1393.96.0.1 to 93.103.255.25493.103.255.255524,286
17493.104.0.0/1393.104.0.1 to 93.111.255.25493.111.255.255524,286
17593.112.0.0/1393.112.0.1 to 93.119.255.25493.119.255.255524,286
17693.120.0.0/1393.120.0.1 to 93.127.255.25493.127.255.255524,286
17793.128.0.0/1393.128.0.1 to 93.135.255.25493.135.255.255524,286
17893.136.0.0/1393.136.0.1 to 93.143.255.25493.143.255.255524,286
17993.144.0.0/1393.144.0.1 to 93.151.255.25493.151.255.255524,286
18093.152.0.0/1393.152.0.1 to 93.159.255.25493.159.255.255524,286
18193.160.0.0/1393.160.0.1 to 93.167.255.25493.167.255.255524,286
18293.168.0.0/1393.168.0.1 to 93.175.255.25493.175.255.255524,286
18393.176.0.0/1393.176.0.1 to 93.183.255.25493.183.255.255524,286
18493.184.0.0/1393.184.0.1 to 93.191.255.25493.191.255.255524,286
18593.192.0.0/1393.192.0.1 to 93.199.255.25493.199.255.255524,286
18693.200.0.0/1393.200.0.1 to 93.207.255.25493.207.255.255524,286
18793.208.0.0/1393.208.0.1 to 93.215.255.25493.215.255.255524,286
18893.216.0.0/1393.216.0.1 to 93.223.255.25493.223.255.255524,286
18993.224.0.0/1393.224.0.1 to 93.231.255.25493.231.255.255524,286
19093.232.0.0/1393.232.0.1 to 93.239.255.25493.239.255.255524,286
19193.240.0.0/1393.240.0.1 to 93.247.255.25493.247.255.255524,286
19293.248.0.0/1393.248.0.1 to 93.255.255.25493.255.255.255524,286
19394.0.0.0/1394.0.0.1 to 94.7.255.25494.7.255.255524,286
19494.8.0.0/1394.8.0.1 to 94.15.255.25494.15.255.255524,286
19594.16.0.0/1394.16.0.1 to 94.23.255.25494.23.255.255524,286
19694.24.0.0/1394.24.0.1 to 94.31.255.25494.31.255.255524,286
19794.32.0.0/1394.32.0.1 to 94.39.255.25494.39.255.255524,286
19894.40.0.0/1394.40.0.1 to 94.47.255.25494.47.255.255524,286
19994.48.0.0/1394.48.0.1 to 94.55.255.25494.55.255.255524,286
20094.56.0.0/1394.56.0.1 to 94.63.255.25494.63.255.255524,286
20194.64.0.0/1394.64.0.1 to 94.71.255.25494.71.255.255524,286
20294.72.0.0/1394.72.0.1 to 94.79.255.25494.79.255.255524,286
20394.80.0.0/1394.80.0.1 to 94.87.255.25494.87.255.255524,286
20494.88.0.0/1394.88.0.1 to 94.95.255.25494.95.255.255524,286
20594.96.0.0/1394.96.0.1 to 94.103.255.25494.103.255.255524,286
20694.104.0.0/1394.104.0.1 to 94.111.255.25494.111.255.255524,286
20794.112.0.0/1394.112.0.1 to 94.119.255.25494.119.255.255524,286
20894.120.0.0/1394.120.0.1 to 94.127.255.25494.127.255.255524,286
20994.128.0.0/1394.128.0.1 to 94.135.255.25494.135.255.255524,286
21094.136.0.0/1394.136.0.1 to 94.143.255.25494.143.255.255524,286
21194.144.0.0/1394.144.0.1 to 94.151.255.25494.151.255.255524,286
21294.152.0.0/1394.152.0.1 to 94.159.255.25494.159.255.255524,286
21394.160.0.0/1394.160.0.1 to 94.167.255.25494.167.255.255524,286
21494.168.0.0/1394.168.0.1 to 94.175.255.25494.175.255.255524,286
21594.176.0.0/1394.176.0.1 to 94.183.255.25494.183.255.255524,286
21694.184.0.0/1394.184.0.1 to 94.191.255.25494.191.255.255524,286
21794.192.0.0/1394.192.0.1 to 94.199.255.25494.199.255.255524,286
21894.200.0.0/1394.200.0.1 to 94.207.255.25494.207.255.255524,286
21994.208.0.0/1394.208.0.1 to 94.215.255.25494.215.255.255524,286
22094.216.0.0/1394.216.0.1 to 94.223.255.25494.223.255.255524,286
22194.224.0.0/1394.224.0.1 to 94.231.255.25494.231.255.255524,286
22294.232.0.0/1394.232.0.1 to 94.239.255.25494.239.255.255524,286
22394.240.0.0/1394.240.0.1 to 94.247.255.25494.247.255.255524,286
22494.248.0.0/1394.248.0.1 to 94.255.255.25494.255.255.255524,286
22595.0.0.0/1395.0.0.1 to 95.7.255.25495.7.255.255524,286
22695.8.0.0/1395.8.0.1 to 95.15.255.25495.15.255.255524,286
22795.16.0.0/1395.16.0.1 to 95.23.255.25495.23.255.255524,286
22895.24.0.0/1395.24.0.1 to 95.31.255.25495.31.255.255524,286
22995.32.0.0/1395.32.0.1 to 95.39.255.25495.39.255.255524,286
23095.40.0.0/1395.40.0.1 to 95.47.255.25495.47.255.255524,286
23195.48.0.0/1395.48.0.1 to 95.55.255.25495.55.255.255524,286
23295.56.0.0/1395.56.0.1 to 95.63.255.25495.63.255.255524,286
23395.64.0.0/1395.64.0.1 to 95.71.255.25495.71.255.255524,286
23495.72.0.0/1395.72.0.1 to 95.79.255.25495.79.255.255524,286
23595.80.0.0/1395.80.0.1 to 95.87.255.25495.87.255.255524,286
23695.88.0.0/1395.88.0.1 to 95.95.255.25495.95.255.255524,286
23795.96.0.0/1395.96.0.1 to 95.103.255.25495.103.255.255524,286
23895.104.0.0/1395.104.0.1 to 95.111.255.25495.111.255.255524,286
23995.112.0.0/1395.112.0.1 to 95.119.255.25495.119.255.255524,286
24095.120.0.0/1395.120.0.1 to 95.127.255.25495.127.255.255524,286
24195.128.0.0/1395.128.0.1 to 95.135.255.25495.135.255.255524,286
24295.136.0.0/1395.136.0.1 to 95.143.255.25495.143.255.255524,286
24395.144.0.0/1395.144.0.1 to 95.151.255.25495.151.255.255524,286
24495.152.0.0/1395.152.0.1 to 95.159.255.25495.159.255.255524,286
24595.160.0.0/1395.160.0.1 to 95.167.255.25495.167.255.255524,286
24695.168.0.0/1395.168.0.1 to 95.175.255.25495.175.255.255524,286
24795.176.0.0/1395.176.0.1 to 95.183.255.25495.183.255.255524,286
24895.184.0.0/1395.184.0.1 to 95.191.255.25495.191.255.255524,286
24995.192.0.0/1395.192.0.1 to 95.199.255.25495.199.255.255524,286
25095.200.0.0/1395.200.0.1 to 95.207.255.25495.207.255.255524,286
25195.208.0.0/1395.208.0.1 to 95.215.255.25495.215.255.255524,286
25295.216.0.0/1395.216.0.1 to 95.223.255.25495.223.255.255524,286
25395.224.0.0/1395.224.0.1 to 95.231.255.25495.231.255.255524,286
25495.232.0.0/1395.232.0.1 to 95.239.255.25495.239.255.255524,286
25595.240.0.0/1395.240.0.1 to 95.247.255.25495.247.255.255524,286
25695.248.0.0/1395.248.0.1 to 95.255.255.25495.255.255.255524,286

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.