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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.

Network9.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
9.0.0.0
Broadcast address
9.255.255.255
First usable
9.0.0.1
Last usable
9.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 09000000 · Integer 150994944 to 167772159
Reverse DNS zone
9.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001001..00000000.00000000.000000009.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network00001001..00000000.00000000.000000009.0.0.0
Broadcast00001001..11111111.11111111.111111119.255.255.255
Split into smaller subnets/16
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

9.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
19.0.0.0/169.0.0.1 to 9.0.255.2549.0.255.25565,534
29.1.0.0/169.1.0.1 to 9.1.255.2549.1.255.25565,534
39.2.0.0/169.2.0.1 to 9.2.255.2549.2.255.25565,534
49.3.0.0/169.3.0.1 to 9.3.255.2549.3.255.25565,534
59.4.0.0/169.4.0.1 to 9.4.255.2549.4.255.25565,534
69.5.0.0/169.5.0.1 to 9.5.255.2549.5.255.25565,534
79.6.0.0/169.6.0.1 to 9.6.255.2549.6.255.25565,534
89.7.0.0/169.7.0.1 to 9.7.255.2549.7.255.25565,534
99.8.0.0/169.8.0.1 to 9.8.255.2549.8.255.25565,534
109.9.0.0/169.9.0.1 to 9.9.255.2549.9.255.25565,534
119.10.0.0/169.10.0.1 to 9.10.255.2549.10.255.25565,534
129.11.0.0/169.11.0.1 to 9.11.255.2549.11.255.25565,534
139.12.0.0/169.12.0.1 to 9.12.255.2549.12.255.25565,534
149.13.0.0/169.13.0.1 to 9.13.255.2549.13.255.25565,534
159.14.0.0/169.14.0.1 to 9.14.255.2549.14.255.25565,534
169.15.0.0/169.15.0.1 to 9.15.255.2549.15.255.25565,534
179.16.0.0/169.16.0.1 to 9.16.255.2549.16.255.25565,534
189.17.0.0/169.17.0.1 to 9.17.255.2549.17.255.25565,534
199.18.0.0/169.18.0.1 to 9.18.255.2549.18.255.25565,534
209.19.0.0/169.19.0.1 to 9.19.255.2549.19.255.25565,534
219.20.0.0/169.20.0.1 to 9.20.255.2549.20.255.25565,534
229.21.0.0/169.21.0.1 to 9.21.255.2549.21.255.25565,534
239.22.0.0/169.22.0.1 to 9.22.255.2549.22.255.25565,534
249.23.0.0/169.23.0.1 to 9.23.255.2549.23.255.25565,534
259.24.0.0/169.24.0.1 to 9.24.255.2549.24.255.25565,534
269.25.0.0/169.25.0.1 to 9.25.255.2549.25.255.25565,534
279.26.0.0/169.26.0.1 to 9.26.255.2549.26.255.25565,534
289.27.0.0/169.27.0.1 to 9.27.255.2549.27.255.25565,534
299.28.0.0/169.28.0.1 to 9.28.255.2549.28.255.25565,534
309.29.0.0/169.29.0.1 to 9.29.255.2549.29.255.25565,534
319.30.0.0/169.30.0.1 to 9.30.255.2549.30.255.25565,534
329.31.0.0/169.31.0.1 to 9.31.255.2549.31.255.25565,534
339.32.0.0/169.32.0.1 to 9.32.255.2549.32.255.25565,534
349.33.0.0/169.33.0.1 to 9.33.255.2549.33.255.25565,534
359.34.0.0/169.34.0.1 to 9.34.255.2549.34.255.25565,534
369.35.0.0/169.35.0.1 to 9.35.255.2549.35.255.25565,534
379.36.0.0/169.36.0.1 to 9.36.255.2549.36.255.25565,534
389.37.0.0/169.37.0.1 to 9.37.255.2549.37.255.25565,534
399.38.0.0/169.38.0.1 to 9.38.255.2549.38.255.25565,534
409.39.0.0/169.39.0.1 to 9.39.255.2549.39.255.25565,534
419.40.0.0/169.40.0.1 to 9.40.255.2549.40.255.25565,534
429.41.0.0/169.41.0.1 to 9.41.255.2549.41.255.25565,534
439.42.0.0/169.42.0.1 to 9.42.255.2549.42.255.25565,534
449.43.0.0/169.43.0.1 to 9.43.255.2549.43.255.25565,534
459.44.0.0/169.44.0.1 to 9.44.255.2549.44.255.25565,534
469.45.0.0/169.45.0.1 to 9.45.255.2549.45.255.25565,534
479.46.0.0/169.46.0.1 to 9.46.255.2549.46.255.25565,534
489.47.0.0/169.47.0.1 to 9.47.255.2549.47.255.25565,534
499.48.0.0/169.48.0.1 to 9.48.255.2549.48.255.25565,534
509.49.0.0/169.49.0.1 to 9.49.255.2549.49.255.25565,534
519.50.0.0/169.50.0.1 to 9.50.255.2549.50.255.25565,534
529.51.0.0/169.51.0.1 to 9.51.255.2549.51.255.25565,534
539.52.0.0/169.52.0.1 to 9.52.255.2549.52.255.25565,534
549.53.0.0/169.53.0.1 to 9.53.255.2549.53.255.25565,534
559.54.0.0/169.54.0.1 to 9.54.255.2549.54.255.25565,534
569.55.0.0/169.55.0.1 to 9.55.255.2549.55.255.25565,534
579.56.0.0/169.56.0.1 to 9.56.255.2549.56.255.25565,534
589.57.0.0/169.57.0.1 to 9.57.255.2549.57.255.25565,534
599.58.0.0/169.58.0.1 to 9.58.255.2549.58.255.25565,534
609.59.0.0/169.59.0.1 to 9.59.255.2549.59.255.25565,534
619.60.0.0/169.60.0.1 to 9.60.255.2549.60.255.25565,534
629.61.0.0/169.61.0.1 to 9.61.255.2549.61.255.25565,534
639.62.0.0/169.62.0.1 to 9.62.255.2549.62.255.25565,534
649.63.0.0/169.63.0.1 to 9.63.255.2549.63.255.25565,534
659.64.0.0/169.64.0.1 to 9.64.255.2549.64.255.25565,534
669.65.0.0/169.65.0.1 to 9.65.255.2549.65.255.25565,534
679.66.0.0/169.66.0.1 to 9.66.255.2549.66.255.25565,534
689.67.0.0/169.67.0.1 to 9.67.255.2549.67.255.25565,534
699.68.0.0/169.68.0.1 to 9.68.255.2549.68.255.25565,534
709.69.0.0/169.69.0.1 to 9.69.255.2549.69.255.25565,534
719.70.0.0/169.70.0.1 to 9.70.255.2549.70.255.25565,534
729.71.0.0/169.71.0.1 to 9.71.255.2549.71.255.25565,534
739.72.0.0/169.72.0.1 to 9.72.255.2549.72.255.25565,534
749.73.0.0/169.73.0.1 to 9.73.255.2549.73.255.25565,534
759.74.0.0/169.74.0.1 to 9.74.255.2549.74.255.25565,534
769.75.0.0/169.75.0.1 to 9.75.255.2549.75.255.25565,534
779.76.0.0/169.76.0.1 to 9.76.255.2549.76.255.25565,534
789.77.0.0/169.77.0.1 to 9.77.255.2549.77.255.25565,534
799.78.0.0/169.78.0.1 to 9.78.255.2549.78.255.25565,534
809.79.0.0/169.79.0.1 to 9.79.255.2549.79.255.25565,534
819.80.0.0/169.80.0.1 to 9.80.255.2549.80.255.25565,534
829.81.0.0/169.81.0.1 to 9.81.255.2549.81.255.25565,534
839.82.0.0/169.82.0.1 to 9.82.255.2549.82.255.25565,534
849.83.0.0/169.83.0.1 to 9.83.255.2549.83.255.25565,534
859.84.0.0/169.84.0.1 to 9.84.255.2549.84.255.25565,534
869.85.0.0/169.85.0.1 to 9.85.255.2549.85.255.25565,534
879.86.0.0/169.86.0.1 to 9.86.255.2549.86.255.25565,534
889.87.0.0/169.87.0.1 to 9.87.255.2549.87.255.25565,534
899.88.0.0/169.88.0.1 to 9.88.255.2549.88.255.25565,534
909.89.0.0/169.89.0.1 to 9.89.255.2549.89.255.25565,534
919.90.0.0/169.90.0.1 to 9.90.255.2549.90.255.25565,534
929.91.0.0/169.91.0.1 to 9.91.255.2549.91.255.25565,534
939.92.0.0/169.92.0.1 to 9.92.255.2549.92.255.25565,534
949.93.0.0/169.93.0.1 to 9.93.255.2549.93.255.25565,534
959.94.0.0/169.94.0.1 to 9.94.255.2549.94.255.25565,534
969.95.0.0/169.95.0.1 to 9.95.255.2549.95.255.25565,534
979.96.0.0/169.96.0.1 to 9.96.255.2549.96.255.25565,534
989.97.0.0/169.97.0.1 to 9.97.255.2549.97.255.25565,534
999.98.0.0/169.98.0.1 to 9.98.255.2549.98.255.25565,534
1009.99.0.0/169.99.0.1 to 9.99.255.2549.99.255.25565,534
1019.100.0.0/169.100.0.1 to 9.100.255.2549.100.255.25565,534
1029.101.0.0/169.101.0.1 to 9.101.255.2549.101.255.25565,534
1039.102.0.0/169.102.0.1 to 9.102.255.2549.102.255.25565,534
1049.103.0.0/169.103.0.1 to 9.103.255.2549.103.255.25565,534
1059.104.0.0/169.104.0.1 to 9.104.255.2549.104.255.25565,534
1069.105.0.0/169.105.0.1 to 9.105.255.2549.105.255.25565,534
1079.106.0.0/169.106.0.1 to 9.106.255.2549.106.255.25565,534
1089.107.0.0/169.107.0.1 to 9.107.255.2549.107.255.25565,534
1099.108.0.0/169.108.0.1 to 9.108.255.2549.108.255.25565,534
1109.109.0.0/169.109.0.1 to 9.109.255.2549.109.255.25565,534
1119.110.0.0/169.110.0.1 to 9.110.255.2549.110.255.25565,534
1129.111.0.0/169.111.0.1 to 9.111.255.2549.111.255.25565,534
1139.112.0.0/169.112.0.1 to 9.112.255.2549.112.255.25565,534
1149.113.0.0/169.113.0.1 to 9.113.255.2549.113.255.25565,534
1159.114.0.0/169.114.0.1 to 9.114.255.2549.114.255.25565,534
1169.115.0.0/169.115.0.1 to 9.115.255.2549.115.255.25565,534
1179.116.0.0/169.116.0.1 to 9.116.255.2549.116.255.25565,534
1189.117.0.0/169.117.0.1 to 9.117.255.2549.117.255.25565,534
1199.118.0.0/169.118.0.1 to 9.118.255.2549.118.255.25565,534
1209.119.0.0/169.119.0.1 to 9.119.255.2549.119.255.25565,534
1219.120.0.0/169.120.0.1 to 9.120.255.2549.120.255.25565,534
1229.121.0.0/169.121.0.1 to 9.121.255.2549.121.255.25565,534
1239.122.0.0/169.122.0.1 to 9.122.255.2549.122.255.25565,534
1249.123.0.0/169.123.0.1 to 9.123.255.2549.123.255.25565,534
1259.124.0.0/169.124.0.1 to 9.124.255.2549.124.255.25565,534
1269.125.0.0/169.125.0.1 to 9.125.255.2549.125.255.25565,534
1279.126.0.0/169.126.0.1 to 9.126.255.2549.126.255.25565,534
1289.127.0.0/169.127.0.1 to 9.127.255.2549.127.255.25565,534
1299.128.0.0/169.128.0.1 to 9.128.255.2549.128.255.25565,534
1309.129.0.0/169.129.0.1 to 9.129.255.2549.129.255.25565,534
1319.130.0.0/169.130.0.1 to 9.130.255.2549.130.255.25565,534
1329.131.0.0/169.131.0.1 to 9.131.255.2549.131.255.25565,534
1339.132.0.0/169.132.0.1 to 9.132.255.2549.132.255.25565,534
1349.133.0.0/169.133.0.1 to 9.133.255.2549.133.255.25565,534
1359.134.0.0/169.134.0.1 to 9.134.255.2549.134.255.25565,534
1369.135.0.0/169.135.0.1 to 9.135.255.2549.135.255.25565,534
1379.136.0.0/169.136.0.1 to 9.136.255.2549.136.255.25565,534
1389.137.0.0/169.137.0.1 to 9.137.255.2549.137.255.25565,534
1399.138.0.0/169.138.0.1 to 9.138.255.2549.138.255.25565,534
1409.139.0.0/169.139.0.1 to 9.139.255.2549.139.255.25565,534
1419.140.0.0/169.140.0.1 to 9.140.255.2549.140.255.25565,534
1429.141.0.0/169.141.0.1 to 9.141.255.2549.141.255.25565,534
1439.142.0.0/169.142.0.1 to 9.142.255.2549.142.255.25565,534
1449.143.0.0/169.143.0.1 to 9.143.255.2549.143.255.25565,534
1459.144.0.0/169.144.0.1 to 9.144.255.2549.144.255.25565,534
1469.145.0.0/169.145.0.1 to 9.145.255.2549.145.255.25565,534
1479.146.0.0/169.146.0.1 to 9.146.255.2549.146.255.25565,534
1489.147.0.0/169.147.0.1 to 9.147.255.2549.147.255.25565,534
1499.148.0.0/169.148.0.1 to 9.148.255.2549.148.255.25565,534
1509.149.0.0/169.149.0.1 to 9.149.255.2549.149.255.25565,534
1519.150.0.0/169.150.0.1 to 9.150.255.2549.150.255.25565,534
1529.151.0.0/169.151.0.1 to 9.151.255.2549.151.255.25565,534
1539.152.0.0/169.152.0.1 to 9.152.255.2549.152.255.25565,534
1549.153.0.0/169.153.0.1 to 9.153.255.2549.153.255.25565,534
1559.154.0.0/169.154.0.1 to 9.154.255.2549.154.255.25565,534
1569.155.0.0/169.155.0.1 to 9.155.255.2549.155.255.25565,534
1579.156.0.0/169.156.0.1 to 9.156.255.2549.156.255.25565,534
1589.157.0.0/169.157.0.1 to 9.157.255.2549.157.255.25565,534
1599.158.0.0/169.158.0.1 to 9.158.255.2549.158.255.25565,534
1609.159.0.0/169.159.0.1 to 9.159.255.2549.159.255.25565,534
1619.160.0.0/169.160.0.1 to 9.160.255.2549.160.255.25565,534
1629.161.0.0/169.161.0.1 to 9.161.255.2549.161.255.25565,534
1639.162.0.0/169.162.0.1 to 9.162.255.2549.162.255.25565,534
1649.163.0.0/169.163.0.1 to 9.163.255.2549.163.255.25565,534
1659.164.0.0/169.164.0.1 to 9.164.255.2549.164.255.25565,534
1669.165.0.0/169.165.0.1 to 9.165.255.2549.165.255.25565,534
1679.166.0.0/169.166.0.1 to 9.166.255.2549.166.255.25565,534
1689.167.0.0/169.167.0.1 to 9.167.255.2549.167.255.25565,534
1699.168.0.0/169.168.0.1 to 9.168.255.2549.168.255.25565,534
1709.169.0.0/169.169.0.1 to 9.169.255.2549.169.255.25565,534
1719.170.0.0/169.170.0.1 to 9.170.255.2549.170.255.25565,534
1729.171.0.0/169.171.0.1 to 9.171.255.2549.171.255.25565,534
1739.172.0.0/169.172.0.1 to 9.172.255.2549.172.255.25565,534
1749.173.0.0/169.173.0.1 to 9.173.255.2549.173.255.25565,534
1759.174.0.0/169.174.0.1 to 9.174.255.2549.174.255.25565,534
1769.175.0.0/169.175.0.1 to 9.175.255.2549.175.255.25565,534
1779.176.0.0/169.176.0.1 to 9.176.255.2549.176.255.25565,534
1789.177.0.0/169.177.0.1 to 9.177.255.2549.177.255.25565,534
1799.178.0.0/169.178.0.1 to 9.178.255.2549.178.255.25565,534
1809.179.0.0/169.179.0.1 to 9.179.255.2549.179.255.25565,534
1819.180.0.0/169.180.0.1 to 9.180.255.2549.180.255.25565,534
1829.181.0.0/169.181.0.1 to 9.181.255.2549.181.255.25565,534
1839.182.0.0/169.182.0.1 to 9.182.255.2549.182.255.25565,534
1849.183.0.0/169.183.0.1 to 9.183.255.2549.183.255.25565,534
1859.184.0.0/169.184.0.1 to 9.184.255.2549.184.255.25565,534
1869.185.0.0/169.185.0.1 to 9.185.255.2549.185.255.25565,534
1879.186.0.0/169.186.0.1 to 9.186.255.2549.186.255.25565,534
1889.187.0.0/169.187.0.1 to 9.187.255.2549.187.255.25565,534
1899.188.0.0/169.188.0.1 to 9.188.255.2549.188.255.25565,534
1909.189.0.0/169.189.0.1 to 9.189.255.2549.189.255.25565,534
1919.190.0.0/169.190.0.1 to 9.190.255.2549.190.255.25565,534
1929.191.0.0/169.191.0.1 to 9.191.255.2549.191.255.25565,534
1939.192.0.0/169.192.0.1 to 9.192.255.2549.192.255.25565,534
1949.193.0.0/169.193.0.1 to 9.193.255.2549.193.255.25565,534
1959.194.0.0/169.194.0.1 to 9.194.255.2549.194.255.25565,534
1969.195.0.0/169.195.0.1 to 9.195.255.2549.195.255.25565,534
1979.196.0.0/169.196.0.1 to 9.196.255.2549.196.255.25565,534
1989.197.0.0/169.197.0.1 to 9.197.255.2549.197.255.25565,534
1999.198.0.0/169.198.0.1 to 9.198.255.2549.198.255.25565,534
2009.199.0.0/169.199.0.1 to 9.199.255.2549.199.255.25565,534
2019.200.0.0/169.200.0.1 to 9.200.255.2549.200.255.25565,534
2029.201.0.0/169.201.0.1 to 9.201.255.2549.201.255.25565,534
2039.202.0.0/169.202.0.1 to 9.202.255.2549.202.255.25565,534
2049.203.0.0/169.203.0.1 to 9.203.255.2549.203.255.25565,534
2059.204.0.0/169.204.0.1 to 9.204.255.2549.204.255.25565,534
2069.205.0.0/169.205.0.1 to 9.205.255.2549.205.255.25565,534
2079.206.0.0/169.206.0.1 to 9.206.255.2549.206.255.25565,534
2089.207.0.0/169.207.0.1 to 9.207.255.2549.207.255.25565,534
2099.208.0.0/169.208.0.1 to 9.208.255.2549.208.255.25565,534
2109.209.0.0/169.209.0.1 to 9.209.255.2549.209.255.25565,534
2119.210.0.0/169.210.0.1 to 9.210.255.2549.210.255.25565,534
2129.211.0.0/169.211.0.1 to 9.211.255.2549.211.255.25565,534
2139.212.0.0/169.212.0.1 to 9.212.255.2549.212.255.25565,534
2149.213.0.0/169.213.0.1 to 9.213.255.2549.213.255.25565,534
2159.214.0.0/169.214.0.1 to 9.214.255.2549.214.255.25565,534
2169.215.0.0/169.215.0.1 to 9.215.255.2549.215.255.25565,534
2179.216.0.0/169.216.0.1 to 9.216.255.2549.216.255.25565,534
2189.217.0.0/169.217.0.1 to 9.217.255.2549.217.255.25565,534
2199.218.0.0/169.218.0.1 to 9.218.255.2549.218.255.25565,534
2209.219.0.0/169.219.0.1 to 9.219.255.2549.219.255.25565,534
2219.220.0.0/169.220.0.1 to 9.220.255.2549.220.255.25565,534
2229.221.0.0/169.221.0.1 to 9.221.255.2549.221.255.25565,534
2239.222.0.0/169.222.0.1 to 9.222.255.2549.222.255.25565,534
2249.223.0.0/169.223.0.1 to 9.223.255.2549.223.255.25565,534
2259.224.0.0/169.224.0.1 to 9.224.255.2549.224.255.25565,534
2269.225.0.0/169.225.0.1 to 9.225.255.2549.225.255.25565,534
2279.226.0.0/169.226.0.1 to 9.226.255.2549.226.255.25565,534
2289.227.0.0/169.227.0.1 to 9.227.255.2549.227.255.25565,534
2299.228.0.0/169.228.0.1 to 9.228.255.2549.228.255.25565,534
2309.229.0.0/169.229.0.1 to 9.229.255.2549.229.255.25565,534
2319.230.0.0/169.230.0.1 to 9.230.255.2549.230.255.25565,534
2329.231.0.0/169.231.0.1 to 9.231.255.2549.231.255.25565,534
2339.232.0.0/169.232.0.1 to 9.232.255.2549.232.255.25565,534
2349.233.0.0/169.233.0.1 to 9.233.255.2549.233.255.25565,534
2359.234.0.0/169.234.0.1 to 9.234.255.2549.234.255.25565,534
2369.235.0.0/169.235.0.1 to 9.235.255.2549.235.255.25565,534
2379.236.0.0/169.236.0.1 to 9.236.255.2549.236.255.25565,534
2389.237.0.0/169.237.0.1 to 9.237.255.2549.237.255.25565,534
2399.238.0.0/169.238.0.1 to 9.238.255.2549.238.255.25565,534
2409.239.0.0/169.239.0.1 to 9.239.255.2549.239.255.25565,534
2419.240.0.0/169.240.0.1 to 9.240.255.2549.240.255.25565,534
2429.241.0.0/169.241.0.1 to 9.241.255.2549.241.255.25565,534
2439.242.0.0/169.242.0.1 to 9.242.255.2549.242.255.25565,534
2449.243.0.0/169.243.0.1 to 9.243.255.2549.243.255.25565,534
2459.244.0.0/169.244.0.1 to 9.244.255.2549.244.255.25565,534
2469.245.0.0/169.245.0.1 to 9.245.255.2549.245.255.25565,534
2479.246.0.0/169.246.0.1 to 9.246.255.2549.246.255.25565,534
2489.247.0.0/169.247.0.1 to 9.247.255.2549.247.255.25565,534
2499.248.0.0/169.248.0.1 to 9.248.255.2549.248.255.25565,534
2509.249.0.0/169.249.0.1 to 9.249.255.2549.249.255.25565,534
2519.250.0.0/169.250.0.1 to 9.250.255.2549.250.255.25565,534
2529.251.0.0/169.251.0.1 to 9.251.255.2549.251.255.25565,534
2539.252.0.0/169.252.0.1 to 9.252.255.2549.252.255.25565,534
2549.253.0.0/169.253.0.1 to 9.253.255.2549.253.255.25565,534
2559.254.0.0/169.254.0.1 to 9.254.255.2549.254.255.25565,534
2569.255.0.0/169.255.0.1 to 9.255.255.2549.255.255.25565,534

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.