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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.

Network9.252.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
9.252.0.0
Broadcast address
9.255.255.255
First usable
9.252.0.1
Last usable
9.255.255.254
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 09FC0000 · Integer 167510016 to 167772159
Reverse DNS zones
252.9.in-addr.arpa
253.9.in-addr.arpa
254.9.in-addr.arpa
255.9.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
Address00001001.11111100.00000000.000000009.252.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00001001.11111100.00000000.000000009.252.0.0
Broadcast00001001.11111111.11111111.111111119.255.255.255
Split into smaller subnets/26
/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)

9.252.0.0/14 makes 4,096 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
19.252.0.0/269.252.0.1 to 9.252.0.629.252.0.6362
29.252.0.64/269.252.0.65 to 9.252.0.1269.252.0.12762
39.252.0.128/269.252.0.129 to 9.252.0.1909.252.0.19162
49.252.0.192/269.252.0.193 to 9.252.0.2549.252.0.25562
59.252.1.0/269.252.1.1 to 9.252.1.629.252.1.6362
69.252.1.64/269.252.1.65 to 9.252.1.1269.252.1.12762
79.252.1.128/269.252.1.129 to 9.252.1.1909.252.1.19162
89.252.1.192/269.252.1.193 to 9.252.1.2549.252.1.25562
99.252.2.0/269.252.2.1 to 9.252.2.629.252.2.6362
109.252.2.64/269.252.2.65 to 9.252.2.1269.252.2.12762
119.252.2.128/269.252.2.129 to 9.252.2.1909.252.2.19162
129.252.2.192/269.252.2.193 to 9.252.2.2549.252.2.25562
139.252.3.0/269.252.3.1 to 9.252.3.629.252.3.6362
149.252.3.64/269.252.3.65 to 9.252.3.1269.252.3.12762
159.252.3.128/269.252.3.129 to 9.252.3.1909.252.3.19162
169.252.3.192/269.252.3.193 to 9.252.3.2549.252.3.25562
179.252.4.0/269.252.4.1 to 9.252.4.629.252.4.6362
189.252.4.64/269.252.4.65 to 9.252.4.1269.252.4.12762
199.252.4.128/269.252.4.129 to 9.252.4.1909.252.4.19162
209.252.4.192/269.252.4.193 to 9.252.4.2549.252.4.25562
219.252.5.0/269.252.5.1 to 9.252.5.629.252.5.6362
229.252.5.64/269.252.5.65 to 9.252.5.1269.252.5.12762
239.252.5.128/269.252.5.129 to 9.252.5.1909.252.5.19162
249.252.5.192/269.252.5.193 to 9.252.5.2549.252.5.25562
259.252.6.0/269.252.6.1 to 9.252.6.629.252.6.6362
269.252.6.64/269.252.6.65 to 9.252.6.1269.252.6.12762
279.252.6.128/269.252.6.129 to 9.252.6.1909.252.6.19162
289.252.6.192/269.252.6.193 to 9.252.6.2549.252.6.25562
299.252.7.0/269.252.7.1 to 9.252.7.629.252.7.6362
309.252.7.64/269.252.7.65 to 9.252.7.1269.252.7.12762
319.252.7.128/269.252.7.129 to 9.252.7.1909.252.7.19162
329.252.7.192/269.252.7.193 to 9.252.7.2549.252.7.25562
339.252.8.0/269.252.8.1 to 9.252.8.629.252.8.6362
349.252.8.64/269.252.8.65 to 9.252.8.1269.252.8.12762
359.252.8.128/269.252.8.129 to 9.252.8.1909.252.8.19162
369.252.8.192/269.252.8.193 to 9.252.8.2549.252.8.25562
379.252.9.0/269.252.9.1 to 9.252.9.629.252.9.6362
389.252.9.64/269.252.9.65 to 9.252.9.1269.252.9.12762
399.252.9.128/269.252.9.129 to 9.252.9.1909.252.9.19162
409.252.9.192/269.252.9.193 to 9.252.9.2549.252.9.25562
419.252.10.0/269.252.10.1 to 9.252.10.629.252.10.6362
429.252.10.64/269.252.10.65 to 9.252.10.1269.252.10.12762
439.252.10.128/269.252.10.129 to 9.252.10.1909.252.10.19162
449.252.10.192/269.252.10.193 to 9.252.10.2549.252.10.25562
459.252.11.0/269.252.11.1 to 9.252.11.629.252.11.6362
469.252.11.64/269.252.11.65 to 9.252.11.1269.252.11.12762
479.252.11.128/269.252.11.129 to 9.252.11.1909.252.11.19162
489.252.11.192/269.252.11.193 to 9.252.11.2549.252.11.25562
499.252.12.0/269.252.12.1 to 9.252.12.629.252.12.6362
509.252.12.64/269.252.12.65 to 9.252.12.1269.252.12.12762
519.252.12.128/269.252.12.129 to 9.252.12.1909.252.12.19162
529.252.12.192/269.252.12.193 to 9.252.12.2549.252.12.25562
539.252.13.0/269.252.13.1 to 9.252.13.629.252.13.6362
549.252.13.64/269.252.13.65 to 9.252.13.1269.252.13.12762
559.252.13.128/269.252.13.129 to 9.252.13.1909.252.13.19162
569.252.13.192/269.252.13.193 to 9.252.13.2549.252.13.25562
579.252.14.0/269.252.14.1 to 9.252.14.629.252.14.6362
589.252.14.64/269.252.14.65 to 9.252.14.1269.252.14.12762
599.252.14.128/269.252.14.129 to 9.252.14.1909.252.14.19162
609.252.14.192/269.252.14.193 to 9.252.14.2549.252.14.25562
619.252.15.0/269.252.15.1 to 9.252.15.629.252.15.6362
629.252.15.64/269.252.15.65 to 9.252.15.1269.252.15.12762
639.252.15.128/269.252.15.129 to 9.252.15.1909.252.15.19162
649.252.15.192/269.252.15.193 to 9.252.15.2549.252.15.25562
659.252.16.0/269.252.16.1 to 9.252.16.629.252.16.6362
669.252.16.64/269.252.16.65 to 9.252.16.1269.252.16.12762
679.252.16.128/269.252.16.129 to 9.252.16.1909.252.16.19162
689.252.16.192/269.252.16.193 to 9.252.16.2549.252.16.25562
699.252.17.0/269.252.17.1 to 9.252.17.629.252.17.6362
709.252.17.64/269.252.17.65 to 9.252.17.1269.252.17.12762
719.252.17.128/269.252.17.129 to 9.252.17.1909.252.17.19162
729.252.17.192/269.252.17.193 to 9.252.17.2549.252.17.25562
739.252.18.0/269.252.18.1 to 9.252.18.629.252.18.6362
749.252.18.64/269.252.18.65 to 9.252.18.1269.252.18.12762
759.252.18.128/269.252.18.129 to 9.252.18.1909.252.18.19162
769.252.18.192/269.252.18.193 to 9.252.18.2549.252.18.25562
779.252.19.0/269.252.19.1 to 9.252.19.629.252.19.6362
789.252.19.64/269.252.19.65 to 9.252.19.1269.252.19.12762
799.252.19.128/269.252.19.129 to 9.252.19.1909.252.19.19162
809.252.19.192/269.252.19.193 to 9.252.19.2549.252.19.25562
819.252.20.0/269.252.20.1 to 9.252.20.629.252.20.6362
829.252.20.64/269.252.20.65 to 9.252.20.1269.252.20.12762
839.252.20.128/269.252.20.129 to 9.252.20.1909.252.20.19162
849.252.20.192/269.252.20.193 to 9.252.20.2549.252.20.25562
859.252.21.0/269.252.21.1 to 9.252.21.629.252.21.6362
869.252.21.64/269.252.21.65 to 9.252.21.1269.252.21.12762
879.252.21.128/269.252.21.129 to 9.252.21.1909.252.21.19162
889.252.21.192/269.252.21.193 to 9.252.21.2549.252.21.25562
899.252.22.0/269.252.22.1 to 9.252.22.629.252.22.6362
909.252.22.64/269.252.22.65 to 9.252.22.1269.252.22.12762
919.252.22.128/269.252.22.129 to 9.252.22.1909.252.22.19162
929.252.22.192/269.252.22.193 to 9.252.22.2549.252.22.25562
939.252.23.0/269.252.23.1 to 9.252.23.629.252.23.6362
949.252.23.64/269.252.23.65 to 9.252.23.1269.252.23.12762
959.252.23.128/269.252.23.129 to 9.252.23.1909.252.23.19162
969.252.23.192/269.252.23.193 to 9.252.23.2549.252.23.25562
979.252.24.0/269.252.24.1 to 9.252.24.629.252.24.6362
989.252.24.64/269.252.24.65 to 9.252.24.1269.252.24.12762
999.252.24.128/269.252.24.129 to 9.252.24.1909.252.24.19162
1009.252.24.192/269.252.24.193 to 9.252.24.2549.252.24.25562
1019.252.25.0/269.252.25.1 to 9.252.25.629.252.25.6362
1029.252.25.64/269.252.25.65 to 9.252.25.1269.252.25.12762
1039.252.25.128/269.252.25.129 to 9.252.25.1909.252.25.19162
1049.252.25.192/269.252.25.193 to 9.252.25.2549.252.25.25562
1059.252.26.0/269.252.26.1 to 9.252.26.629.252.26.6362
1069.252.26.64/269.252.26.65 to 9.252.26.1269.252.26.12762
1079.252.26.128/269.252.26.129 to 9.252.26.1909.252.26.19162
1089.252.26.192/269.252.26.193 to 9.252.26.2549.252.26.25562
1099.252.27.0/269.252.27.1 to 9.252.27.629.252.27.6362
1109.252.27.64/269.252.27.65 to 9.252.27.1269.252.27.12762
1119.252.27.128/269.252.27.129 to 9.252.27.1909.252.27.19162
1129.252.27.192/269.252.27.193 to 9.252.27.2549.252.27.25562
1139.252.28.0/269.252.28.1 to 9.252.28.629.252.28.6362
1149.252.28.64/269.252.28.65 to 9.252.28.1269.252.28.12762
1159.252.28.128/269.252.28.129 to 9.252.28.1909.252.28.19162
1169.252.28.192/269.252.28.193 to 9.252.28.2549.252.28.25562
1179.252.29.0/269.252.29.1 to 9.252.29.629.252.29.6362
1189.252.29.64/269.252.29.65 to 9.252.29.1269.252.29.12762
1199.252.29.128/269.252.29.129 to 9.252.29.1909.252.29.19162
1209.252.29.192/269.252.29.193 to 9.252.29.2549.252.29.25562
1219.252.30.0/269.252.30.1 to 9.252.30.629.252.30.6362
1229.252.30.64/269.252.30.65 to 9.252.30.1269.252.30.12762
1239.252.30.128/269.252.30.129 to 9.252.30.1909.252.30.19162
1249.252.30.192/269.252.30.193 to 9.252.30.2549.252.30.25562
1259.252.31.0/269.252.31.1 to 9.252.31.629.252.31.6362
1269.252.31.64/269.252.31.65 to 9.252.31.1269.252.31.12762
1279.252.31.128/269.252.31.129 to 9.252.31.1909.252.31.19162
1289.252.31.192/269.252.31.193 to 9.252.31.2549.252.31.25562
1299.252.32.0/269.252.32.1 to 9.252.32.629.252.32.6362
1309.252.32.64/269.252.32.65 to 9.252.32.1269.252.32.12762
1319.252.32.128/269.252.32.129 to 9.252.32.1909.252.32.19162
1329.252.32.192/269.252.32.193 to 9.252.32.2549.252.32.25562
1339.252.33.0/269.252.33.1 to 9.252.33.629.252.33.6362
1349.252.33.64/269.252.33.65 to 9.252.33.1269.252.33.12762
1359.252.33.128/269.252.33.129 to 9.252.33.1909.252.33.19162
1369.252.33.192/269.252.33.193 to 9.252.33.2549.252.33.25562
1379.252.34.0/269.252.34.1 to 9.252.34.629.252.34.6362
1389.252.34.64/269.252.34.65 to 9.252.34.1269.252.34.12762
1399.252.34.128/269.252.34.129 to 9.252.34.1909.252.34.19162
1409.252.34.192/269.252.34.193 to 9.252.34.2549.252.34.25562
1419.252.35.0/269.252.35.1 to 9.252.35.629.252.35.6362
1429.252.35.64/269.252.35.65 to 9.252.35.1269.252.35.12762
1439.252.35.128/269.252.35.129 to 9.252.35.1909.252.35.19162
1449.252.35.192/269.252.35.193 to 9.252.35.2549.252.35.25562
1459.252.36.0/269.252.36.1 to 9.252.36.629.252.36.6362
1469.252.36.64/269.252.36.65 to 9.252.36.1269.252.36.12762
1479.252.36.128/269.252.36.129 to 9.252.36.1909.252.36.19162
1489.252.36.192/269.252.36.193 to 9.252.36.2549.252.36.25562
1499.252.37.0/269.252.37.1 to 9.252.37.629.252.37.6362
1509.252.37.64/269.252.37.65 to 9.252.37.1269.252.37.12762
1519.252.37.128/269.252.37.129 to 9.252.37.1909.252.37.19162
1529.252.37.192/269.252.37.193 to 9.252.37.2549.252.37.25562
1539.252.38.0/269.252.38.1 to 9.252.38.629.252.38.6362
1549.252.38.64/269.252.38.65 to 9.252.38.1269.252.38.12762
1559.252.38.128/269.252.38.129 to 9.252.38.1909.252.38.19162
1569.252.38.192/269.252.38.193 to 9.252.38.2549.252.38.25562
1579.252.39.0/269.252.39.1 to 9.252.39.629.252.39.6362
1589.252.39.64/269.252.39.65 to 9.252.39.1269.252.39.12762
1599.252.39.128/269.252.39.129 to 9.252.39.1909.252.39.19162
1609.252.39.192/269.252.39.193 to 9.252.39.2549.252.39.25562
1619.252.40.0/269.252.40.1 to 9.252.40.629.252.40.6362
1629.252.40.64/269.252.40.65 to 9.252.40.1269.252.40.12762
1639.252.40.128/269.252.40.129 to 9.252.40.1909.252.40.19162
1649.252.40.192/269.252.40.193 to 9.252.40.2549.252.40.25562
1659.252.41.0/269.252.41.1 to 9.252.41.629.252.41.6362
1669.252.41.64/269.252.41.65 to 9.252.41.1269.252.41.12762
1679.252.41.128/269.252.41.129 to 9.252.41.1909.252.41.19162
1689.252.41.192/269.252.41.193 to 9.252.41.2549.252.41.25562
1699.252.42.0/269.252.42.1 to 9.252.42.629.252.42.6362
1709.252.42.64/269.252.42.65 to 9.252.42.1269.252.42.12762
1719.252.42.128/269.252.42.129 to 9.252.42.1909.252.42.19162
1729.252.42.192/269.252.42.193 to 9.252.42.2549.252.42.25562
1739.252.43.0/269.252.43.1 to 9.252.43.629.252.43.6362
1749.252.43.64/269.252.43.65 to 9.252.43.1269.252.43.12762
1759.252.43.128/269.252.43.129 to 9.252.43.1909.252.43.19162
1769.252.43.192/269.252.43.193 to 9.252.43.2549.252.43.25562
1779.252.44.0/269.252.44.1 to 9.252.44.629.252.44.6362
1789.252.44.64/269.252.44.65 to 9.252.44.1269.252.44.12762
1799.252.44.128/269.252.44.129 to 9.252.44.1909.252.44.19162
1809.252.44.192/269.252.44.193 to 9.252.44.2549.252.44.25562
1819.252.45.0/269.252.45.1 to 9.252.45.629.252.45.6362
1829.252.45.64/269.252.45.65 to 9.252.45.1269.252.45.12762
1839.252.45.128/269.252.45.129 to 9.252.45.1909.252.45.19162
1849.252.45.192/269.252.45.193 to 9.252.45.2549.252.45.25562
1859.252.46.0/269.252.46.1 to 9.252.46.629.252.46.6362
1869.252.46.64/269.252.46.65 to 9.252.46.1269.252.46.12762
1879.252.46.128/269.252.46.129 to 9.252.46.1909.252.46.19162
1889.252.46.192/269.252.46.193 to 9.252.46.2549.252.46.25562
1899.252.47.0/269.252.47.1 to 9.252.47.629.252.47.6362
1909.252.47.64/269.252.47.65 to 9.252.47.1269.252.47.12762
1919.252.47.128/269.252.47.129 to 9.252.47.1909.252.47.19162
1929.252.47.192/269.252.47.193 to 9.252.47.2549.252.47.25562
1939.252.48.0/269.252.48.1 to 9.252.48.629.252.48.6362
1949.252.48.64/269.252.48.65 to 9.252.48.1269.252.48.12762
1959.252.48.128/269.252.48.129 to 9.252.48.1909.252.48.19162
1969.252.48.192/269.252.48.193 to 9.252.48.2549.252.48.25562
1979.252.49.0/269.252.49.1 to 9.252.49.629.252.49.6362
1989.252.49.64/269.252.49.65 to 9.252.49.1269.252.49.12762
1999.252.49.128/269.252.49.129 to 9.252.49.1909.252.49.19162
2009.252.49.192/269.252.49.193 to 9.252.49.2549.252.49.25562
2019.252.50.0/269.252.50.1 to 9.252.50.629.252.50.6362
2029.252.50.64/269.252.50.65 to 9.252.50.1269.252.50.12762
2039.252.50.128/269.252.50.129 to 9.252.50.1909.252.50.19162
2049.252.50.192/269.252.50.193 to 9.252.50.2549.252.50.25562
2059.252.51.0/269.252.51.1 to 9.252.51.629.252.51.6362
2069.252.51.64/269.252.51.65 to 9.252.51.1269.252.51.12762
2079.252.51.128/269.252.51.129 to 9.252.51.1909.252.51.19162
2089.252.51.192/269.252.51.193 to 9.252.51.2549.252.51.25562
2099.252.52.0/269.252.52.1 to 9.252.52.629.252.52.6362
2109.252.52.64/269.252.52.65 to 9.252.52.1269.252.52.12762
2119.252.52.128/269.252.52.129 to 9.252.52.1909.252.52.19162
2129.252.52.192/269.252.52.193 to 9.252.52.2549.252.52.25562
2139.252.53.0/269.252.53.1 to 9.252.53.629.252.53.6362
2149.252.53.64/269.252.53.65 to 9.252.53.1269.252.53.12762
2159.252.53.128/269.252.53.129 to 9.252.53.1909.252.53.19162
2169.252.53.192/269.252.53.193 to 9.252.53.2549.252.53.25562
2179.252.54.0/269.252.54.1 to 9.252.54.629.252.54.6362
2189.252.54.64/269.252.54.65 to 9.252.54.1269.252.54.12762
2199.252.54.128/269.252.54.129 to 9.252.54.1909.252.54.19162
2209.252.54.192/269.252.54.193 to 9.252.54.2549.252.54.25562
2219.252.55.0/269.252.55.1 to 9.252.55.629.252.55.6362
2229.252.55.64/269.252.55.65 to 9.252.55.1269.252.55.12762
2239.252.55.128/269.252.55.129 to 9.252.55.1909.252.55.19162
2249.252.55.192/269.252.55.193 to 9.252.55.2549.252.55.25562
2259.252.56.0/269.252.56.1 to 9.252.56.629.252.56.6362
2269.252.56.64/269.252.56.65 to 9.252.56.1269.252.56.12762
2279.252.56.128/269.252.56.129 to 9.252.56.1909.252.56.19162
2289.252.56.192/269.252.56.193 to 9.252.56.2549.252.56.25562
2299.252.57.0/269.252.57.1 to 9.252.57.629.252.57.6362
2309.252.57.64/269.252.57.65 to 9.252.57.1269.252.57.12762
2319.252.57.128/269.252.57.129 to 9.252.57.1909.252.57.19162
2329.252.57.192/269.252.57.193 to 9.252.57.2549.252.57.25562
2339.252.58.0/269.252.58.1 to 9.252.58.629.252.58.6362
2349.252.58.64/269.252.58.65 to 9.252.58.1269.252.58.12762
2359.252.58.128/269.252.58.129 to 9.252.58.1909.252.58.19162
2369.252.58.192/269.252.58.193 to 9.252.58.2549.252.58.25562
2379.252.59.0/269.252.59.1 to 9.252.59.629.252.59.6362
2389.252.59.64/269.252.59.65 to 9.252.59.1269.252.59.12762
2399.252.59.128/269.252.59.129 to 9.252.59.1909.252.59.19162
2409.252.59.192/269.252.59.193 to 9.252.59.2549.252.59.25562
2419.252.60.0/269.252.60.1 to 9.252.60.629.252.60.6362
2429.252.60.64/269.252.60.65 to 9.252.60.1269.252.60.12762
2439.252.60.128/269.252.60.129 to 9.252.60.1909.252.60.19162
2449.252.60.192/269.252.60.193 to 9.252.60.2549.252.60.25562
2459.252.61.0/269.252.61.1 to 9.252.61.629.252.61.6362
2469.252.61.64/269.252.61.65 to 9.252.61.1269.252.61.12762
2479.252.61.128/269.252.61.129 to 9.252.61.1909.252.61.19162
2489.252.61.192/269.252.61.193 to 9.252.61.2549.252.61.25562
2499.252.62.0/269.252.62.1 to 9.252.62.629.252.62.6362
2509.252.62.64/269.252.62.65 to 9.252.62.1269.252.62.12762
2519.252.62.128/269.252.62.129 to 9.252.62.1909.252.62.19162
2529.252.62.192/269.252.62.193 to 9.252.62.2549.252.62.25562
2539.252.63.0/269.252.63.1 to 9.252.63.629.252.63.6362
2549.252.63.64/269.252.63.65 to 9.252.63.1269.252.63.12762
2559.252.63.128/269.252.63.129 to 9.252.63.1909.252.63.19162
2569.252.63.192/269.252.63.193 to 9.252.63.2549.252.63.25562

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.