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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.

Network9.204.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
9.204.0.0
Broadcast address
9.207.255.255
First usable
9.204.0.1
Last usable
9.207.255.254
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 09CC0000 · Integer 164364288 to 164626431
Reverse DNS zones
204.9.in-addr.arpa
205.9.in-addr.arpa
206.9.in-addr.arpa
207.9.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
Address00001001.11001100.00000000.000000009.204.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00001001.11001100.00000000.000000009.204.0.0
Broadcast00001001.11001111.11111111.111111119.207.255.255
Split into smaller subnets/24
/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)

9.204.0.0/14 makes 1,024 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
19.204.0.0/249.204.0.1 to 9.204.0.2549.204.0.255254
29.204.1.0/249.204.1.1 to 9.204.1.2549.204.1.255254
39.204.2.0/249.204.2.1 to 9.204.2.2549.204.2.255254
49.204.3.0/249.204.3.1 to 9.204.3.2549.204.3.255254
59.204.4.0/249.204.4.1 to 9.204.4.2549.204.4.255254
69.204.5.0/249.204.5.1 to 9.204.5.2549.204.5.255254
79.204.6.0/249.204.6.1 to 9.204.6.2549.204.6.255254
89.204.7.0/249.204.7.1 to 9.204.7.2549.204.7.255254
99.204.8.0/249.204.8.1 to 9.204.8.2549.204.8.255254
109.204.9.0/249.204.9.1 to 9.204.9.2549.204.9.255254
119.204.10.0/249.204.10.1 to 9.204.10.2549.204.10.255254
129.204.11.0/249.204.11.1 to 9.204.11.2549.204.11.255254
139.204.12.0/249.204.12.1 to 9.204.12.2549.204.12.255254
149.204.13.0/249.204.13.1 to 9.204.13.2549.204.13.255254
159.204.14.0/249.204.14.1 to 9.204.14.2549.204.14.255254
169.204.15.0/249.204.15.1 to 9.204.15.2549.204.15.255254
179.204.16.0/249.204.16.1 to 9.204.16.2549.204.16.255254
189.204.17.0/249.204.17.1 to 9.204.17.2549.204.17.255254
199.204.18.0/249.204.18.1 to 9.204.18.2549.204.18.255254
209.204.19.0/249.204.19.1 to 9.204.19.2549.204.19.255254
219.204.20.0/249.204.20.1 to 9.204.20.2549.204.20.255254
229.204.21.0/249.204.21.1 to 9.204.21.2549.204.21.255254
239.204.22.0/249.204.22.1 to 9.204.22.2549.204.22.255254
249.204.23.0/249.204.23.1 to 9.204.23.2549.204.23.255254
259.204.24.0/249.204.24.1 to 9.204.24.2549.204.24.255254
269.204.25.0/249.204.25.1 to 9.204.25.2549.204.25.255254
279.204.26.0/249.204.26.1 to 9.204.26.2549.204.26.255254
289.204.27.0/249.204.27.1 to 9.204.27.2549.204.27.255254
299.204.28.0/249.204.28.1 to 9.204.28.2549.204.28.255254
309.204.29.0/249.204.29.1 to 9.204.29.2549.204.29.255254
319.204.30.0/249.204.30.1 to 9.204.30.2549.204.30.255254
329.204.31.0/249.204.31.1 to 9.204.31.2549.204.31.255254
339.204.32.0/249.204.32.1 to 9.204.32.2549.204.32.255254
349.204.33.0/249.204.33.1 to 9.204.33.2549.204.33.255254
359.204.34.0/249.204.34.1 to 9.204.34.2549.204.34.255254
369.204.35.0/249.204.35.1 to 9.204.35.2549.204.35.255254
379.204.36.0/249.204.36.1 to 9.204.36.2549.204.36.255254
389.204.37.0/249.204.37.1 to 9.204.37.2549.204.37.255254
399.204.38.0/249.204.38.1 to 9.204.38.2549.204.38.255254
409.204.39.0/249.204.39.1 to 9.204.39.2549.204.39.255254
419.204.40.0/249.204.40.1 to 9.204.40.2549.204.40.255254
429.204.41.0/249.204.41.1 to 9.204.41.2549.204.41.255254
439.204.42.0/249.204.42.1 to 9.204.42.2549.204.42.255254
449.204.43.0/249.204.43.1 to 9.204.43.2549.204.43.255254
459.204.44.0/249.204.44.1 to 9.204.44.2549.204.44.255254
469.204.45.0/249.204.45.1 to 9.204.45.2549.204.45.255254
479.204.46.0/249.204.46.1 to 9.204.46.2549.204.46.255254
489.204.47.0/249.204.47.1 to 9.204.47.2549.204.47.255254
499.204.48.0/249.204.48.1 to 9.204.48.2549.204.48.255254
509.204.49.0/249.204.49.1 to 9.204.49.2549.204.49.255254
519.204.50.0/249.204.50.1 to 9.204.50.2549.204.50.255254
529.204.51.0/249.204.51.1 to 9.204.51.2549.204.51.255254
539.204.52.0/249.204.52.1 to 9.204.52.2549.204.52.255254
549.204.53.0/249.204.53.1 to 9.204.53.2549.204.53.255254
559.204.54.0/249.204.54.1 to 9.204.54.2549.204.54.255254
569.204.55.0/249.204.55.1 to 9.204.55.2549.204.55.255254
579.204.56.0/249.204.56.1 to 9.204.56.2549.204.56.255254
589.204.57.0/249.204.57.1 to 9.204.57.2549.204.57.255254
599.204.58.0/249.204.58.1 to 9.204.58.2549.204.58.255254
609.204.59.0/249.204.59.1 to 9.204.59.2549.204.59.255254
619.204.60.0/249.204.60.1 to 9.204.60.2549.204.60.255254
629.204.61.0/249.204.61.1 to 9.204.61.2549.204.61.255254
639.204.62.0/249.204.62.1 to 9.204.62.2549.204.62.255254
649.204.63.0/249.204.63.1 to 9.204.63.2549.204.63.255254
659.204.64.0/249.204.64.1 to 9.204.64.2549.204.64.255254
669.204.65.0/249.204.65.1 to 9.204.65.2549.204.65.255254
679.204.66.0/249.204.66.1 to 9.204.66.2549.204.66.255254
689.204.67.0/249.204.67.1 to 9.204.67.2549.204.67.255254
699.204.68.0/249.204.68.1 to 9.204.68.2549.204.68.255254
709.204.69.0/249.204.69.1 to 9.204.69.2549.204.69.255254
719.204.70.0/249.204.70.1 to 9.204.70.2549.204.70.255254
729.204.71.0/249.204.71.1 to 9.204.71.2549.204.71.255254
739.204.72.0/249.204.72.1 to 9.204.72.2549.204.72.255254
749.204.73.0/249.204.73.1 to 9.204.73.2549.204.73.255254
759.204.74.0/249.204.74.1 to 9.204.74.2549.204.74.255254
769.204.75.0/249.204.75.1 to 9.204.75.2549.204.75.255254
779.204.76.0/249.204.76.1 to 9.204.76.2549.204.76.255254
789.204.77.0/249.204.77.1 to 9.204.77.2549.204.77.255254
799.204.78.0/249.204.78.1 to 9.204.78.2549.204.78.255254
809.204.79.0/249.204.79.1 to 9.204.79.2549.204.79.255254
819.204.80.0/249.204.80.1 to 9.204.80.2549.204.80.255254
829.204.81.0/249.204.81.1 to 9.204.81.2549.204.81.255254
839.204.82.0/249.204.82.1 to 9.204.82.2549.204.82.255254
849.204.83.0/249.204.83.1 to 9.204.83.2549.204.83.255254
859.204.84.0/249.204.84.1 to 9.204.84.2549.204.84.255254
869.204.85.0/249.204.85.1 to 9.204.85.2549.204.85.255254
879.204.86.0/249.204.86.1 to 9.204.86.2549.204.86.255254
889.204.87.0/249.204.87.1 to 9.204.87.2549.204.87.255254
899.204.88.0/249.204.88.1 to 9.204.88.2549.204.88.255254
909.204.89.0/249.204.89.1 to 9.204.89.2549.204.89.255254
919.204.90.0/249.204.90.1 to 9.204.90.2549.204.90.255254
929.204.91.0/249.204.91.1 to 9.204.91.2549.204.91.255254
939.204.92.0/249.204.92.1 to 9.204.92.2549.204.92.255254
949.204.93.0/249.204.93.1 to 9.204.93.2549.204.93.255254
959.204.94.0/249.204.94.1 to 9.204.94.2549.204.94.255254
969.204.95.0/249.204.95.1 to 9.204.95.2549.204.95.255254
979.204.96.0/249.204.96.1 to 9.204.96.2549.204.96.255254
989.204.97.0/249.204.97.1 to 9.204.97.2549.204.97.255254
999.204.98.0/249.204.98.1 to 9.204.98.2549.204.98.255254
1009.204.99.0/249.204.99.1 to 9.204.99.2549.204.99.255254
1019.204.100.0/249.204.100.1 to 9.204.100.2549.204.100.255254
1029.204.101.0/249.204.101.1 to 9.204.101.2549.204.101.255254
1039.204.102.0/249.204.102.1 to 9.204.102.2549.204.102.255254
1049.204.103.0/249.204.103.1 to 9.204.103.2549.204.103.255254
1059.204.104.0/249.204.104.1 to 9.204.104.2549.204.104.255254
1069.204.105.0/249.204.105.1 to 9.204.105.2549.204.105.255254
1079.204.106.0/249.204.106.1 to 9.204.106.2549.204.106.255254
1089.204.107.0/249.204.107.1 to 9.204.107.2549.204.107.255254
1099.204.108.0/249.204.108.1 to 9.204.108.2549.204.108.255254
1109.204.109.0/249.204.109.1 to 9.204.109.2549.204.109.255254
1119.204.110.0/249.204.110.1 to 9.204.110.2549.204.110.255254
1129.204.111.0/249.204.111.1 to 9.204.111.2549.204.111.255254
1139.204.112.0/249.204.112.1 to 9.204.112.2549.204.112.255254
1149.204.113.0/249.204.113.1 to 9.204.113.2549.204.113.255254
1159.204.114.0/249.204.114.1 to 9.204.114.2549.204.114.255254
1169.204.115.0/249.204.115.1 to 9.204.115.2549.204.115.255254
1179.204.116.0/249.204.116.1 to 9.204.116.2549.204.116.255254
1189.204.117.0/249.204.117.1 to 9.204.117.2549.204.117.255254
1199.204.118.0/249.204.118.1 to 9.204.118.2549.204.118.255254
1209.204.119.0/249.204.119.1 to 9.204.119.2549.204.119.255254
1219.204.120.0/249.204.120.1 to 9.204.120.2549.204.120.255254
1229.204.121.0/249.204.121.1 to 9.204.121.2549.204.121.255254
1239.204.122.0/249.204.122.1 to 9.204.122.2549.204.122.255254
1249.204.123.0/249.204.123.1 to 9.204.123.2549.204.123.255254
1259.204.124.0/249.204.124.1 to 9.204.124.2549.204.124.255254
1269.204.125.0/249.204.125.1 to 9.204.125.2549.204.125.255254
1279.204.126.0/249.204.126.1 to 9.204.126.2549.204.126.255254
1289.204.127.0/249.204.127.1 to 9.204.127.2549.204.127.255254
1299.204.128.0/249.204.128.1 to 9.204.128.2549.204.128.255254
1309.204.129.0/249.204.129.1 to 9.204.129.2549.204.129.255254
1319.204.130.0/249.204.130.1 to 9.204.130.2549.204.130.255254
1329.204.131.0/249.204.131.1 to 9.204.131.2549.204.131.255254
1339.204.132.0/249.204.132.1 to 9.204.132.2549.204.132.255254
1349.204.133.0/249.204.133.1 to 9.204.133.2549.204.133.255254
1359.204.134.0/249.204.134.1 to 9.204.134.2549.204.134.255254
1369.204.135.0/249.204.135.1 to 9.204.135.2549.204.135.255254
1379.204.136.0/249.204.136.1 to 9.204.136.2549.204.136.255254
1389.204.137.0/249.204.137.1 to 9.204.137.2549.204.137.255254
1399.204.138.0/249.204.138.1 to 9.204.138.2549.204.138.255254
1409.204.139.0/249.204.139.1 to 9.204.139.2549.204.139.255254
1419.204.140.0/249.204.140.1 to 9.204.140.2549.204.140.255254
1429.204.141.0/249.204.141.1 to 9.204.141.2549.204.141.255254
1439.204.142.0/249.204.142.1 to 9.204.142.2549.204.142.255254
1449.204.143.0/249.204.143.1 to 9.204.143.2549.204.143.255254
1459.204.144.0/249.204.144.1 to 9.204.144.2549.204.144.255254
1469.204.145.0/249.204.145.1 to 9.204.145.2549.204.145.255254
1479.204.146.0/249.204.146.1 to 9.204.146.2549.204.146.255254
1489.204.147.0/249.204.147.1 to 9.204.147.2549.204.147.255254
1499.204.148.0/249.204.148.1 to 9.204.148.2549.204.148.255254
1509.204.149.0/249.204.149.1 to 9.204.149.2549.204.149.255254
1519.204.150.0/249.204.150.1 to 9.204.150.2549.204.150.255254
1529.204.151.0/249.204.151.1 to 9.204.151.2549.204.151.255254
1539.204.152.0/249.204.152.1 to 9.204.152.2549.204.152.255254
1549.204.153.0/249.204.153.1 to 9.204.153.2549.204.153.255254
1559.204.154.0/249.204.154.1 to 9.204.154.2549.204.154.255254
1569.204.155.0/249.204.155.1 to 9.204.155.2549.204.155.255254
1579.204.156.0/249.204.156.1 to 9.204.156.2549.204.156.255254
1589.204.157.0/249.204.157.1 to 9.204.157.2549.204.157.255254
1599.204.158.0/249.204.158.1 to 9.204.158.2549.204.158.255254
1609.204.159.0/249.204.159.1 to 9.204.159.2549.204.159.255254
1619.204.160.0/249.204.160.1 to 9.204.160.2549.204.160.255254
1629.204.161.0/249.204.161.1 to 9.204.161.2549.204.161.255254
1639.204.162.0/249.204.162.1 to 9.204.162.2549.204.162.255254
1649.204.163.0/249.204.163.1 to 9.204.163.2549.204.163.255254
1659.204.164.0/249.204.164.1 to 9.204.164.2549.204.164.255254
1669.204.165.0/249.204.165.1 to 9.204.165.2549.204.165.255254
1679.204.166.0/249.204.166.1 to 9.204.166.2549.204.166.255254
1689.204.167.0/249.204.167.1 to 9.204.167.2549.204.167.255254
1699.204.168.0/249.204.168.1 to 9.204.168.2549.204.168.255254
1709.204.169.0/249.204.169.1 to 9.204.169.2549.204.169.255254
1719.204.170.0/249.204.170.1 to 9.204.170.2549.204.170.255254
1729.204.171.0/249.204.171.1 to 9.204.171.2549.204.171.255254
1739.204.172.0/249.204.172.1 to 9.204.172.2549.204.172.255254
1749.204.173.0/249.204.173.1 to 9.204.173.2549.204.173.255254
1759.204.174.0/249.204.174.1 to 9.204.174.2549.204.174.255254
1769.204.175.0/249.204.175.1 to 9.204.175.2549.204.175.255254
1779.204.176.0/249.204.176.1 to 9.204.176.2549.204.176.255254
1789.204.177.0/249.204.177.1 to 9.204.177.2549.204.177.255254
1799.204.178.0/249.204.178.1 to 9.204.178.2549.204.178.255254
1809.204.179.0/249.204.179.1 to 9.204.179.2549.204.179.255254
1819.204.180.0/249.204.180.1 to 9.204.180.2549.204.180.255254
1829.204.181.0/249.204.181.1 to 9.204.181.2549.204.181.255254
1839.204.182.0/249.204.182.1 to 9.204.182.2549.204.182.255254
1849.204.183.0/249.204.183.1 to 9.204.183.2549.204.183.255254
1859.204.184.0/249.204.184.1 to 9.204.184.2549.204.184.255254
1869.204.185.0/249.204.185.1 to 9.204.185.2549.204.185.255254
1879.204.186.0/249.204.186.1 to 9.204.186.2549.204.186.255254
1889.204.187.0/249.204.187.1 to 9.204.187.2549.204.187.255254
1899.204.188.0/249.204.188.1 to 9.204.188.2549.204.188.255254
1909.204.189.0/249.204.189.1 to 9.204.189.2549.204.189.255254
1919.204.190.0/249.204.190.1 to 9.204.190.2549.204.190.255254
1929.204.191.0/249.204.191.1 to 9.204.191.2549.204.191.255254
1939.204.192.0/249.204.192.1 to 9.204.192.2549.204.192.255254
1949.204.193.0/249.204.193.1 to 9.204.193.2549.204.193.255254
1959.204.194.0/249.204.194.1 to 9.204.194.2549.204.194.255254
1969.204.195.0/249.204.195.1 to 9.204.195.2549.204.195.255254
1979.204.196.0/249.204.196.1 to 9.204.196.2549.204.196.255254
1989.204.197.0/249.204.197.1 to 9.204.197.2549.204.197.255254
1999.204.198.0/249.204.198.1 to 9.204.198.2549.204.198.255254
2009.204.199.0/249.204.199.1 to 9.204.199.2549.204.199.255254
2019.204.200.0/249.204.200.1 to 9.204.200.2549.204.200.255254
2029.204.201.0/249.204.201.1 to 9.204.201.2549.204.201.255254
2039.204.202.0/249.204.202.1 to 9.204.202.2549.204.202.255254
2049.204.203.0/249.204.203.1 to 9.204.203.2549.204.203.255254
2059.204.204.0/249.204.204.1 to 9.204.204.2549.204.204.255254
2069.204.205.0/249.204.205.1 to 9.204.205.2549.204.205.255254
2079.204.206.0/249.204.206.1 to 9.204.206.2549.204.206.255254
2089.204.207.0/249.204.207.1 to 9.204.207.2549.204.207.255254
2099.204.208.0/249.204.208.1 to 9.204.208.2549.204.208.255254
2109.204.209.0/249.204.209.1 to 9.204.209.2549.204.209.255254
2119.204.210.0/249.204.210.1 to 9.204.210.2549.204.210.255254
2129.204.211.0/249.204.211.1 to 9.204.211.2549.204.211.255254
2139.204.212.0/249.204.212.1 to 9.204.212.2549.204.212.255254
2149.204.213.0/249.204.213.1 to 9.204.213.2549.204.213.255254
2159.204.214.0/249.204.214.1 to 9.204.214.2549.204.214.255254
2169.204.215.0/249.204.215.1 to 9.204.215.2549.204.215.255254
2179.204.216.0/249.204.216.1 to 9.204.216.2549.204.216.255254
2189.204.217.0/249.204.217.1 to 9.204.217.2549.204.217.255254
2199.204.218.0/249.204.218.1 to 9.204.218.2549.204.218.255254
2209.204.219.0/249.204.219.1 to 9.204.219.2549.204.219.255254
2219.204.220.0/249.204.220.1 to 9.204.220.2549.204.220.255254
2229.204.221.0/249.204.221.1 to 9.204.221.2549.204.221.255254
2239.204.222.0/249.204.222.1 to 9.204.222.2549.204.222.255254
2249.204.223.0/249.204.223.1 to 9.204.223.2549.204.223.255254
2259.204.224.0/249.204.224.1 to 9.204.224.2549.204.224.255254
2269.204.225.0/249.204.225.1 to 9.204.225.2549.204.225.255254
2279.204.226.0/249.204.226.1 to 9.204.226.2549.204.226.255254
2289.204.227.0/249.204.227.1 to 9.204.227.2549.204.227.255254
2299.204.228.0/249.204.228.1 to 9.204.228.2549.204.228.255254
2309.204.229.0/249.204.229.1 to 9.204.229.2549.204.229.255254
2319.204.230.0/249.204.230.1 to 9.204.230.2549.204.230.255254
2329.204.231.0/249.204.231.1 to 9.204.231.2549.204.231.255254
2339.204.232.0/249.204.232.1 to 9.204.232.2549.204.232.255254
2349.204.233.0/249.204.233.1 to 9.204.233.2549.204.233.255254
2359.204.234.0/249.204.234.1 to 9.204.234.2549.204.234.255254
2369.204.235.0/249.204.235.1 to 9.204.235.2549.204.235.255254
2379.204.236.0/249.204.236.1 to 9.204.236.2549.204.236.255254
2389.204.237.0/249.204.237.1 to 9.204.237.2549.204.237.255254
2399.204.238.0/249.204.238.1 to 9.204.238.2549.204.238.255254
2409.204.239.0/249.204.239.1 to 9.204.239.2549.204.239.255254
2419.204.240.0/249.204.240.1 to 9.204.240.2549.204.240.255254
2429.204.241.0/249.204.241.1 to 9.204.241.2549.204.241.255254
2439.204.242.0/249.204.242.1 to 9.204.242.2549.204.242.255254
2449.204.243.0/249.204.243.1 to 9.204.243.2549.204.243.255254
2459.204.244.0/249.204.244.1 to 9.204.244.2549.204.244.255254
2469.204.245.0/249.204.245.1 to 9.204.245.2549.204.245.255254
2479.204.246.0/249.204.246.1 to 9.204.246.2549.204.246.255254
2489.204.247.0/249.204.247.1 to 9.204.247.2549.204.247.255254
2499.204.248.0/249.204.248.1 to 9.204.248.2549.204.248.255254
2509.204.249.0/249.204.249.1 to 9.204.249.2549.204.249.255254
2519.204.250.0/249.204.250.1 to 9.204.250.2549.204.250.255254
2529.204.251.0/249.204.251.1 to 9.204.251.2549.204.251.255254
2539.204.252.0/249.204.252.1 to 9.204.252.2549.204.252.255254
2549.204.253.0/249.204.253.1 to 9.204.253.2549.204.253.255254
2559.204.254.0/249.204.254.1 to 9.204.254.2549.204.254.255254
2569.204.255.0/249.204.255.1 to 9.204.255.2549.204.255.255254

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.