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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.

Prefix/116
Addresses4,096
/64 networksPart of one
Network
2c19:dd:c25:c25d:dd:dd:dd:8000/116
First address
2c19:dd:c25:c25d:dd:dd:dd:8000
Last address
2c19:dd:c25:c25d:dd:dd:dd:8fff
Addresses
4,096
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:8000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/127
/117 (2)/118 (4)/119 (8)/120 (16)/124 (256)/127 (2,048)/128 (4,096)

2c19:dd:c25:c25d:dd:dd:dd:8000/116 makes 2,048 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:8000/1272c19:dd:c25:c25d:dd:dd:dd:8001
22c19:dd:c25:c25d:dd:dd:dd:8002/1272c19:dd:c25:c25d:dd:dd:dd:8003
32c19:dd:c25:c25d:dd:dd:dd:8004/1272c19:dd:c25:c25d:dd:dd:dd:8005
42c19:dd:c25:c25d:dd:dd:dd:8006/1272c19:dd:c25:c25d:dd:dd:dd:8007
52c19:dd:c25:c25d:dd:dd:dd:8008/1272c19:dd:c25:c25d:dd:dd:dd:8009
62c19:dd:c25:c25d:dd:dd:dd:800a/1272c19:dd:c25:c25d:dd:dd:dd:800b
72c19:dd:c25:c25d:dd:dd:dd:800c/1272c19:dd:c25:c25d:dd:dd:dd:800d
82c19:dd:c25:c25d:dd:dd:dd:800e/1272c19:dd:c25:c25d:dd:dd:dd:800f
92c19:dd:c25:c25d:dd:dd:dd:8010/1272c19:dd:c25:c25d:dd:dd:dd:8011
102c19:dd:c25:c25d:dd:dd:dd:8012/1272c19:dd:c25:c25d:dd:dd:dd:8013
112c19:dd:c25:c25d:dd:dd:dd:8014/1272c19:dd:c25:c25d:dd:dd:dd:8015
122c19:dd:c25:c25d:dd:dd:dd:8016/1272c19:dd:c25:c25d:dd:dd:dd:8017
132c19:dd:c25:c25d:dd:dd:dd:8018/1272c19:dd:c25:c25d:dd:dd:dd:8019
142c19:dd:c25:c25d:dd:dd:dd:801a/1272c19:dd:c25:c25d:dd:dd:dd:801b
152c19:dd:c25:c25d:dd:dd:dd:801c/1272c19:dd:c25:c25d:dd:dd:dd:801d
162c19:dd:c25:c25d:dd:dd:dd:801e/1272c19:dd:c25:c25d:dd:dd:dd:801f
172c19:dd:c25:c25d:dd:dd:dd:8020/1272c19:dd:c25:c25d:dd:dd:dd:8021
182c19:dd:c25:c25d:dd:dd:dd:8022/1272c19:dd:c25:c25d:dd:dd:dd:8023
192c19:dd:c25:c25d:dd:dd:dd:8024/1272c19:dd:c25:c25d:dd:dd:dd:8025
202c19:dd:c25:c25d:dd:dd:dd:8026/1272c19:dd:c25:c25d:dd:dd:dd:8027
212c19:dd:c25:c25d:dd:dd:dd:8028/1272c19:dd:c25:c25d:dd:dd:dd:8029
222c19:dd:c25:c25d:dd:dd:dd:802a/1272c19:dd:c25:c25d:dd:dd:dd:802b
232c19:dd:c25:c25d:dd:dd:dd:802c/1272c19:dd:c25:c25d:dd:dd:dd:802d
242c19:dd:c25:c25d:dd:dd:dd:802e/1272c19:dd:c25:c25d:dd:dd:dd:802f
252c19:dd:c25:c25d:dd:dd:dd:8030/1272c19:dd:c25:c25d:dd:dd:dd:8031
262c19:dd:c25:c25d:dd:dd:dd:8032/1272c19:dd:c25:c25d:dd:dd:dd:8033
272c19:dd:c25:c25d:dd:dd:dd:8034/1272c19:dd:c25:c25d:dd:dd:dd:8035
282c19:dd:c25:c25d:dd:dd:dd:8036/1272c19:dd:c25:c25d:dd:dd:dd:8037
292c19:dd:c25:c25d:dd:dd:dd:8038/1272c19:dd:c25:c25d:dd:dd:dd:8039
302c19:dd:c25:c25d:dd:dd:dd:803a/1272c19:dd:c25:c25d:dd:dd:dd:803b
312c19:dd:c25:c25d:dd:dd:dd:803c/1272c19:dd:c25:c25d:dd:dd:dd:803d
322c19:dd:c25:c25d:dd:dd:dd:803e/1272c19:dd:c25:c25d:dd:dd:dd:803f
332c19:dd:c25:c25d:dd:dd:dd:8040/1272c19:dd:c25:c25d:dd:dd:dd:8041
342c19:dd:c25:c25d:dd:dd:dd:8042/1272c19:dd:c25:c25d:dd:dd:dd:8043
352c19:dd:c25:c25d:dd:dd:dd:8044/1272c19:dd:c25:c25d:dd:dd:dd:8045
362c19:dd:c25:c25d:dd:dd:dd:8046/1272c19:dd:c25:c25d:dd:dd:dd:8047
372c19:dd:c25:c25d:dd:dd:dd:8048/1272c19:dd:c25:c25d:dd:dd:dd:8049
382c19:dd:c25:c25d:dd:dd:dd:804a/1272c19:dd:c25:c25d:dd:dd:dd:804b
392c19:dd:c25:c25d:dd:dd:dd:804c/1272c19:dd:c25:c25d:dd:dd:dd:804d
402c19:dd:c25:c25d:dd:dd:dd:804e/1272c19:dd:c25:c25d:dd:dd:dd:804f
412c19:dd:c25:c25d:dd:dd:dd:8050/1272c19:dd:c25:c25d:dd:dd:dd:8051
422c19:dd:c25:c25d:dd:dd:dd:8052/1272c19:dd:c25:c25d:dd:dd:dd:8053
432c19:dd:c25:c25d:dd:dd:dd:8054/1272c19:dd:c25:c25d:dd:dd:dd:8055
442c19:dd:c25:c25d:dd:dd:dd:8056/1272c19:dd:c25:c25d:dd:dd:dd:8057
452c19:dd:c25:c25d:dd:dd:dd:8058/1272c19:dd:c25:c25d:dd:dd:dd:8059
462c19:dd:c25:c25d:dd:dd:dd:805a/1272c19:dd:c25:c25d:dd:dd:dd:805b
472c19:dd:c25:c25d:dd:dd:dd:805c/1272c19:dd:c25:c25d:dd:dd:dd:805d
482c19:dd:c25:c25d:dd:dd:dd:805e/1272c19:dd:c25:c25d:dd:dd:dd:805f
492c19:dd:c25:c25d:dd:dd:dd:8060/1272c19:dd:c25:c25d:dd:dd:dd:8061
502c19:dd:c25:c25d:dd:dd:dd:8062/1272c19:dd:c25:c25d:dd:dd:dd:8063
512c19:dd:c25:c25d:dd:dd:dd:8064/1272c19:dd:c25:c25d:dd:dd:dd:8065
522c19:dd:c25:c25d:dd:dd:dd:8066/1272c19:dd:c25:c25d:dd:dd:dd:8067
532c19:dd:c25:c25d:dd:dd:dd:8068/1272c19:dd:c25:c25d:dd:dd:dd:8069
542c19:dd:c25:c25d:dd:dd:dd:806a/1272c19:dd:c25:c25d:dd:dd:dd:806b
552c19:dd:c25:c25d:dd:dd:dd:806c/1272c19:dd:c25:c25d:dd:dd:dd:806d
562c19:dd:c25:c25d:dd:dd:dd:806e/1272c19:dd:c25:c25d:dd:dd:dd:806f
572c19:dd:c25:c25d:dd:dd:dd:8070/1272c19:dd:c25:c25d:dd:dd:dd:8071
582c19:dd:c25:c25d:dd:dd:dd:8072/1272c19:dd:c25:c25d:dd:dd:dd:8073
592c19:dd:c25:c25d:dd:dd:dd:8074/1272c19:dd:c25:c25d:dd:dd:dd:8075
602c19:dd:c25:c25d:dd:dd:dd:8076/1272c19:dd:c25:c25d:dd:dd:dd:8077
612c19:dd:c25:c25d:dd:dd:dd:8078/1272c19:dd:c25:c25d:dd:dd:dd:8079
622c19:dd:c25:c25d:dd:dd:dd:807a/1272c19:dd:c25:c25d:dd:dd:dd:807b
632c19:dd:c25:c25d:dd:dd:dd:807c/1272c19:dd:c25:c25d:dd:dd:dd:807d
642c19:dd:c25:c25d:dd:dd:dd:807e/1272c19:dd:c25:c25d:dd:dd:dd:807f
652c19:dd:c25:c25d:dd:dd:dd:8080/1272c19:dd:c25:c25d:dd:dd:dd:8081
662c19:dd:c25:c25d:dd:dd:dd:8082/1272c19:dd:c25:c25d:dd:dd:dd:8083
672c19:dd:c25:c25d:dd:dd:dd:8084/1272c19:dd:c25:c25d:dd:dd:dd:8085
682c19:dd:c25:c25d:dd:dd:dd:8086/1272c19:dd:c25:c25d:dd:dd:dd:8087
692c19:dd:c25:c25d:dd:dd:dd:8088/1272c19:dd:c25:c25d:dd:dd:dd:8089
702c19:dd:c25:c25d:dd:dd:dd:808a/1272c19:dd:c25:c25d:dd:dd:dd:808b
712c19:dd:c25:c25d:dd:dd:dd:808c/1272c19:dd:c25:c25d:dd:dd:dd:808d
722c19:dd:c25:c25d:dd:dd:dd:808e/1272c19:dd:c25:c25d:dd:dd:dd:808f
732c19:dd:c25:c25d:dd:dd:dd:8090/1272c19:dd:c25:c25d:dd:dd:dd:8091
742c19:dd:c25:c25d:dd:dd:dd:8092/1272c19:dd:c25:c25d:dd:dd:dd:8093
752c19:dd:c25:c25d:dd:dd:dd:8094/1272c19:dd:c25:c25d:dd:dd:dd:8095
762c19:dd:c25:c25d:dd:dd:dd:8096/1272c19:dd:c25:c25d:dd:dd:dd:8097
772c19:dd:c25:c25d:dd:dd:dd:8098/1272c19:dd:c25:c25d:dd:dd:dd:8099
782c19:dd:c25:c25d:dd:dd:dd:809a/1272c19:dd:c25:c25d:dd:dd:dd:809b
792c19:dd:c25:c25d:dd:dd:dd:809c/1272c19:dd:c25:c25d:dd:dd:dd:809d
802c19:dd:c25:c25d:dd:dd:dd:809e/1272c19:dd:c25:c25d:dd:dd:dd:809f
812c19:dd:c25:c25d:dd:dd:dd:80a0/1272c19:dd:c25:c25d:dd:dd:dd:80a1
822c19:dd:c25:c25d:dd:dd:dd:80a2/1272c19:dd:c25:c25d:dd:dd:dd:80a3
832c19:dd:c25:c25d:dd:dd:dd:80a4/1272c19:dd:c25:c25d:dd:dd:dd:80a5
842c19:dd:c25:c25d:dd:dd:dd:80a6/1272c19:dd:c25:c25d:dd:dd:dd:80a7
852c19:dd:c25:c25d:dd:dd:dd:80a8/1272c19:dd:c25:c25d:dd:dd:dd:80a9
862c19:dd:c25:c25d:dd:dd:dd:80aa/1272c19:dd:c25:c25d:dd:dd:dd:80ab
872c19:dd:c25:c25d:dd:dd:dd:80ac/1272c19:dd:c25:c25d:dd:dd:dd:80ad
882c19:dd:c25:c25d:dd:dd:dd:80ae/1272c19:dd:c25:c25d:dd:dd:dd:80af
892c19:dd:c25:c25d:dd:dd:dd:80b0/1272c19:dd:c25:c25d:dd:dd:dd:80b1
902c19:dd:c25:c25d:dd:dd:dd:80b2/1272c19:dd:c25:c25d:dd:dd:dd:80b3
912c19:dd:c25:c25d:dd:dd:dd:80b4/1272c19:dd:c25:c25d:dd:dd:dd:80b5
922c19:dd:c25:c25d:dd:dd:dd:80b6/1272c19:dd:c25:c25d:dd:dd:dd:80b7
932c19:dd:c25:c25d:dd:dd:dd:80b8/1272c19:dd:c25:c25d:dd:dd:dd:80b9
942c19:dd:c25:c25d:dd:dd:dd:80ba/1272c19:dd:c25:c25d:dd:dd:dd:80bb
952c19:dd:c25:c25d:dd:dd:dd:80bc/1272c19:dd:c25:c25d:dd:dd:dd:80bd
962c19:dd:c25:c25d:dd:dd:dd:80be/1272c19:dd:c25:c25d:dd:dd:dd:80bf
972c19:dd:c25:c25d:dd:dd:dd:80c0/1272c19:dd:c25:c25d:dd:dd:dd:80c1
982c19:dd:c25:c25d:dd:dd:dd:80c2/1272c19:dd:c25:c25d:dd:dd:dd:80c3
992c19:dd:c25:c25d:dd:dd:dd:80c4/1272c19:dd:c25:c25d:dd:dd:dd:80c5
1002c19:dd:c25:c25d:dd:dd:dd:80c6/1272c19:dd:c25:c25d:dd:dd:dd:80c7
1012c19:dd:c25:c25d:dd:dd:dd:80c8/1272c19:dd:c25:c25d:dd:dd:dd:80c9
1022c19:dd:c25:c25d:dd:dd:dd:80ca/1272c19:dd:c25:c25d:dd:dd:dd:80cb
1032c19:dd:c25:c25d:dd:dd:dd:80cc/1272c19:dd:c25:c25d:dd:dd:dd:80cd
1042c19:dd:c25:c25d:dd:dd:dd:80ce/1272c19:dd:c25:c25d:dd:dd:dd:80cf
1052c19:dd:c25:c25d:dd:dd:dd:80d0/1272c19:dd:c25:c25d:dd:dd:dd:80d1
1062c19:dd:c25:c25d:dd:dd:dd:80d2/1272c19:dd:c25:c25d:dd:dd:dd:80d3
1072c19:dd:c25:c25d:dd:dd:dd:80d4/1272c19:dd:c25:c25d:dd:dd:dd:80d5
1082c19:dd:c25:c25d:dd:dd:dd:80d6/1272c19:dd:c25:c25d:dd:dd:dd:80d7
1092c19:dd:c25:c25d:dd:dd:dd:80d8/1272c19:dd:c25:c25d:dd:dd:dd:80d9
1102c19:dd:c25:c25d:dd:dd:dd:80da/1272c19:dd:c25:c25d:dd:dd:dd:80db
1112c19:dd:c25:c25d:dd:dd:dd:80dc/1272c19:dd:c25:c25d:dd:dd:dd:80dd
1122c19:dd:c25:c25d:dd:dd:dd:80de/1272c19:dd:c25:c25d:dd:dd:dd:80df
1132c19:dd:c25:c25d:dd:dd:dd:80e0/1272c19:dd:c25:c25d:dd:dd:dd:80e1
1142c19:dd:c25:c25d:dd:dd:dd:80e2/1272c19:dd:c25:c25d:dd:dd:dd:80e3
1152c19:dd:c25:c25d:dd:dd:dd:80e4/1272c19:dd:c25:c25d:dd:dd:dd:80e5
1162c19:dd:c25:c25d:dd:dd:dd:80e6/1272c19:dd:c25:c25d:dd:dd:dd:80e7
1172c19:dd:c25:c25d:dd:dd:dd:80e8/1272c19:dd:c25:c25d:dd:dd:dd:80e9
1182c19:dd:c25:c25d:dd:dd:dd:80ea/1272c19:dd:c25:c25d:dd:dd:dd:80eb
1192c19:dd:c25:c25d:dd:dd:dd:80ec/1272c19:dd:c25:c25d:dd:dd:dd:80ed
1202c19:dd:c25:c25d:dd:dd:dd:80ee/1272c19:dd:c25:c25d:dd:dd:dd:80ef
1212c19:dd:c25:c25d:dd:dd:dd:80f0/1272c19:dd:c25:c25d:dd:dd:dd:80f1
1222c19:dd:c25:c25d:dd:dd:dd:80f2/1272c19:dd:c25:c25d:dd:dd:dd:80f3
1232c19:dd:c25:c25d:dd:dd:dd:80f4/1272c19:dd:c25:c25d:dd:dd:dd:80f5
1242c19:dd:c25:c25d:dd:dd:dd:80f6/1272c19:dd:c25:c25d:dd:dd:dd:80f7
1252c19:dd:c25:c25d:dd:dd:dd:80f8/1272c19:dd:c25:c25d:dd:dd:dd:80f9
1262c19:dd:c25:c25d:dd:dd:dd:80fa/1272c19:dd:c25:c25d:dd:dd:dd:80fb
1272c19:dd:c25:c25d:dd:dd:dd:80fc/1272c19:dd:c25:c25d:dd:dd:dd:80fd
1282c19:dd:c25:c25d:dd:dd:dd:80fe/1272c19:dd:c25:c25d:dd:dd:dd:80ff
1292c19:dd:c25:c25d:dd:dd:dd:8100/1272c19:dd:c25:c25d:dd:dd:dd:8101
1302c19:dd:c25:c25d:dd:dd:dd:8102/1272c19:dd:c25:c25d:dd:dd:dd:8103
1312c19:dd:c25:c25d:dd:dd:dd:8104/1272c19:dd:c25:c25d:dd:dd:dd:8105
1322c19:dd:c25:c25d:dd:dd:dd:8106/1272c19:dd:c25:c25d:dd:dd:dd:8107
1332c19:dd:c25:c25d:dd:dd:dd:8108/1272c19:dd:c25:c25d:dd:dd:dd:8109
1342c19:dd:c25:c25d:dd:dd:dd:810a/1272c19:dd:c25:c25d:dd:dd:dd:810b
1352c19:dd:c25:c25d:dd:dd:dd:810c/1272c19:dd:c25:c25d:dd:dd:dd:810d
1362c19:dd:c25:c25d:dd:dd:dd:810e/1272c19:dd:c25:c25d:dd:dd:dd:810f
1372c19:dd:c25:c25d:dd:dd:dd:8110/1272c19:dd:c25:c25d:dd:dd:dd:8111
1382c19:dd:c25:c25d:dd:dd:dd:8112/1272c19:dd:c25:c25d:dd:dd:dd:8113
1392c19:dd:c25:c25d:dd:dd:dd:8114/1272c19:dd:c25:c25d:dd:dd:dd:8115
1402c19:dd:c25:c25d:dd:dd:dd:8116/1272c19:dd:c25:c25d:dd:dd:dd:8117
1412c19:dd:c25:c25d:dd:dd:dd:8118/1272c19:dd:c25:c25d:dd:dd:dd:8119
1422c19:dd:c25:c25d:dd:dd:dd:811a/1272c19:dd:c25:c25d:dd:dd:dd:811b
1432c19:dd:c25:c25d:dd:dd:dd:811c/1272c19:dd:c25:c25d:dd:dd:dd:811d
1442c19:dd:c25:c25d:dd:dd:dd:811e/1272c19:dd:c25:c25d:dd:dd:dd:811f
1452c19:dd:c25:c25d:dd:dd:dd:8120/1272c19:dd:c25:c25d:dd:dd:dd:8121
1462c19:dd:c25:c25d:dd:dd:dd:8122/1272c19:dd:c25:c25d:dd:dd:dd:8123
1472c19:dd:c25:c25d:dd:dd:dd:8124/1272c19:dd:c25:c25d:dd:dd:dd:8125
1482c19:dd:c25:c25d:dd:dd:dd:8126/1272c19:dd:c25:c25d:dd:dd:dd:8127
1492c19:dd:c25:c25d:dd:dd:dd:8128/1272c19:dd:c25:c25d:dd:dd:dd:8129
1502c19:dd:c25:c25d:dd:dd:dd:812a/1272c19:dd:c25:c25d:dd:dd:dd:812b
1512c19:dd:c25:c25d:dd:dd:dd:812c/1272c19:dd:c25:c25d:dd:dd:dd:812d
1522c19:dd:c25:c25d:dd:dd:dd:812e/1272c19:dd:c25:c25d:dd:dd:dd:812f
1532c19:dd:c25:c25d:dd:dd:dd:8130/1272c19:dd:c25:c25d:dd:dd:dd:8131
1542c19:dd:c25:c25d:dd:dd:dd:8132/1272c19:dd:c25:c25d:dd:dd:dd:8133
1552c19:dd:c25:c25d:dd:dd:dd:8134/1272c19:dd:c25:c25d:dd:dd:dd:8135
1562c19:dd:c25:c25d:dd:dd:dd:8136/1272c19:dd:c25:c25d:dd:dd:dd:8137
1572c19:dd:c25:c25d:dd:dd:dd:8138/1272c19:dd:c25:c25d:dd:dd:dd:8139
1582c19:dd:c25:c25d:dd:dd:dd:813a/1272c19:dd:c25:c25d:dd:dd:dd:813b
1592c19:dd:c25:c25d:dd:dd:dd:813c/1272c19:dd:c25:c25d:dd:dd:dd:813d
1602c19:dd:c25:c25d:dd:dd:dd:813e/1272c19:dd:c25:c25d:dd:dd:dd:813f
1612c19:dd:c25:c25d:dd:dd:dd:8140/1272c19:dd:c25:c25d:dd:dd:dd:8141
1622c19:dd:c25:c25d:dd:dd:dd:8142/1272c19:dd:c25:c25d:dd:dd:dd:8143
1632c19:dd:c25:c25d:dd:dd:dd:8144/1272c19:dd:c25:c25d:dd:dd:dd:8145
1642c19:dd:c25:c25d:dd:dd:dd:8146/1272c19:dd:c25:c25d:dd:dd:dd:8147
1652c19:dd:c25:c25d:dd:dd:dd:8148/1272c19:dd:c25:c25d:dd:dd:dd:8149
1662c19:dd:c25:c25d:dd:dd:dd:814a/1272c19:dd:c25:c25d:dd:dd:dd:814b
1672c19:dd:c25:c25d:dd:dd:dd:814c/1272c19:dd:c25:c25d:dd:dd:dd:814d
1682c19:dd:c25:c25d:dd:dd:dd:814e/1272c19:dd:c25:c25d:dd:dd:dd:814f
1692c19:dd:c25:c25d:dd:dd:dd:8150/1272c19:dd:c25:c25d:dd:dd:dd:8151
1702c19:dd:c25:c25d:dd:dd:dd:8152/1272c19:dd:c25:c25d:dd:dd:dd:8153
1712c19:dd:c25:c25d:dd:dd:dd:8154/1272c19:dd:c25:c25d:dd:dd:dd:8155
1722c19:dd:c25:c25d:dd:dd:dd:8156/1272c19:dd:c25:c25d:dd:dd:dd:8157
1732c19:dd:c25:c25d:dd:dd:dd:8158/1272c19:dd:c25:c25d:dd:dd:dd:8159
1742c19:dd:c25:c25d:dd:dd:dd:815a/1272c19:dd:c25:c25d:dd:dd:dd:815b
1752c19:dd:c25:c25d:dd:dd:dd:815c/1272c19:dd:c25:c25d:dd:dd:dd:815d
1762c19:dd:c25:c25d:dd:dd:dd:815e/1272c19:dd:c25:c25d:dd:dd:dd:815f
1772c19:dd:c25:c25d:dd:dd:dd:8160/1272c19:dd:c25:c25d:dd:dd:dd:8161
1782c19:dd:c25:c25d:dd:dd:dd:8162/1272c19:dd:c25:c25d:dd:dd:dd:8163
1792c19:dd:c25:c25d:dd:dd:dd:8164/1272c19:dd:c25:c25d:dd:dd:dd:8165
1802c19:dd:c25:c25d:dd:dd:dd:8166/1272c19:dd:c25:c25d:dd:dd:dd:8167
1812c19:dd:c25:c25d:dd:dd:dd:8168/1272c19:dd:c25:c25d:dd:dd:dd:8169
1822c19:dd:c25:c25d:dd:dd:dd:816a/1272c19:dd:c25:c25d:dd:dd:dd:816b
1832c19:dd:c25:c25d:dd:dd:dd:816c/1272c19:dd:c25:c25d:dd:dd:dd:816d
1842c19:dd:c25:c25d:dd:dd:dd:816e/1272c19:dd:c25:c25d:dd:dd:dd:816f
1852c19:dd:c25:c25d:dd:dd:dd:8170/1272c19:dd:c25:c25d:dd:dd:dd:8171
1862c19:dd:c25:c25d:dd:dd:dd:8172/1272c19:dd:c25:c25d:dd:dd:dd:8173
1872c19:dd:c25:c25d:dd:dd:dd:8174/1272c19:dd:c25:c25d:dd:dd:dd:8175
1882c19:dd:c25:c25d:dd:dd:dd:8176/1272c19:dd:c25:c25d:dd:dd:dd:8177
1892c19:dd:c25:c25d:dd:dd:dd:8178/1272c19:dd:c25:c25d:dd:dd:dd:8179
1902c19:dd:c25:c25d:dd:dd:dd:817a/1272c19:dd:c25:c25d:dd:dd:dd:817b
1912c19:dd:c25:c25d:dd:dd:dd:817c/1272c19:dd:c25:c25d:dd:dd:dd:817d
1922c19:dd:c25:c25d:dd:dd:dd:817e/1272c19:dd:c25:c25d:dd:dd:dd:817f
1932c19:dd:c25:c25d:dd:dd:dd:8180/1272c19:dd:c25:c25d:dd:dd:dd:8181
1942c19:dd:c25:c25d:dd:dd:dd:8182/1272c19:dd:c25:c25d:dd:dd:dd:8183
1952c19:dd:c25:c25d:dd:dd:dd:8184/1272c19:dd:c25:c25d:dd:dd:dd:8185
1962c19:dd:c25:c25d:dd:dd:dd:8186/1272c19:dd:c25:c25d:dd:dd:dd:8187
1972c19:dd:c25:c25d:dd:dd:dd:8188/1272c19:dd:c25:c25d:dd:dd:dd:8189
1982c19:dd:c25:c25d:dd:dd:dd:818a/1272c19:dd:c25:c25d:dd:dd:dd:818b
1992c19:dd:c25:c25d:dd:dd:dd:818c/1272c19:dd:c25:c25d:dd:dd:dd:818d
2002c19:dd:c25:c25d:dd:dd:dd:818e/1272c19:dd:c25:c25d:dd:dd:dd:818f
2012c19:dd:c25:c25d:dd:dd:dd:8190/1272c19:dd:c25:c25d:dd:dd:dd:8191
2022c19:dd:c25:c25d:dd:dd:dd:8192/1272c19:dd:c25:c25d:dd:dd:dd:8193
2032c19:dd:c25:c25d:dd:dd:dd:8194/1272c19:dd:c25:c25d:dd:dd:dd:8195
2042c19:dd:c25:c25d:dd:dd:dd:8196/1272c19:dd:c25:c25d:dd:dd:dd:8197
2052c19:dd:c25:c25d:dd:dd:dd:8198/1272c19:dd:c25:c25d:dd:dd:dd:8199
2062c19:dd:c25:c25d:dd:dd:dd:819a/1272c19:dd:c25:c25d:dd:dd:dd:819b
2072c19:dd:c25:c25d:dd:dd:dd:819c/1272c19:dd:c25:c25d:dd:dd:dd:819d
2082c19:dd:c25:c25d:dd:dd:dd:819e/1272c19:dd:c25:c25d:dd:dd:dd:819f
2092c19:dd:c25:c25d:dd:dd:dd:81a0/1272c19:dd:c25:c25d:dd:dd:dd:81a1
2102c19:dd:c25:c25d:dd:dd:dd:81a2/1272c19:dd:c25:c25d:dd:dd:dd:81a3
2112c19:dd:c25:c25d:dd:dd:dd:81a4/1272c19:dd:c25:c25d:dd:dd:dd:81a5
2122c19:dd:c25:c25d:dd:dd:dd:81a6/1272c19:dd:c25:c25d:dd:dd:dd:81a7
2132c19:dd:c25:c25d:dd:dd:dd:81a8/1272c19:dd:c25:c25d:dd:dd:dd:81a9
2142c19:dd:c25:c25d:dd:dd:dd:81aa/1272c19:dd:c25:c25d:dd:dd:dd:81ab
2152c19:dd:c25:c25d:dd:dd:dd:81ac/1272c19:dd:c25:c25d:dd:dd:dd:81ad
2162c19:dd:c25:c25d:dd:dd:dd:81ae/1272c19:dd:c25:c25d:dd:dd:dd:81af
2172c19:dd:c25:c25d:dd:dd:dd:81b0/1272c19:dd:c25:c25d:dd:dd:dd:81b1
2182c19:dd:c25:c25d:dd:dd:dd:81b2/1272c19:dd:c25:c25d:dd:dd:dd:81b3
2192c19:dd:c25:c25d:dd:dd:dd:81b4/1272c19:dd:c25:c25d:dd:dd:dd:81b5
2202c19:dd:c25:c25d:dd:dd:dd:81b6/1272c19:dd:c25:c25d:dd:dd:dd:81b7
2212c19:dd:c25:c25d:dd:dd:dd:81b8/1272c19:dd:c25:c25d:dd:dd:dd:81b9
2222c19:dd:c25:c25d:dd:dd:dd:81ba/1272c19:dd:c25:c25d:dd:dd:dd:81bb
2232c19:dd:c25:c25d:dd:dd:dd:81bc/1272c19:dd:c25:c25d:dd:dd:dd:81bd
2242c19:dd:c25:c25d:dd:dd:dd:81be/1272c19:dd:c25:c25d:dd:dd:dd:81bf
2252c19:dd:c25:c25d:dd:dd:dd:81c0/1272c19:dd:c25:c25d:dd:dd:dd:81c1
2262c19:dd:c25:c25d:dd:dd:dd:81c2/1272c19:dd:c25:c25d:dd:dd:dd:81c3
2272c19:dd:c25:c25d:dd:dd:dd:81c4/1272c19:dd:c25:c25d:dd:dd:dd:81c5
2282c19:dd:c25:c25d:dd:dd:dd:81c6/1272c19:dd:c25:c25d:dd:dd:dd:81c7
2292c19:dd:c25:c25d:dd:dd:dd:81c8/1272c19:dd:c25:c25d:dd:dd:dd:81c9
2302c19:dd:c25:c25d:dd:dd:dd:81ca/1272c19:dd:c25:c25d:dd:dd:dd:81cb
2312c19:dd:c25:c25d:dd:dd:dd:81cc/1272c19:dd:c25:c25d:dd:dd:dd:81cd
2322c19:dd:c25:c25d:dd:dd:dd:81ce/1272c19:dd:c25:c25d:dd:dd:dd:81cf
2332c19:dd:c25:c25d:dd:dd:dd:81d0/1272c19:dd:c25:c25d:dd:dd:dd:81d1
2342c19:dd:c25:c25d:dd:dd:dd:81d2/1272c19:dd:c25:c25d:dd:dd:dd:81d3
2352c19:dd:c25:c25d:dd:dd:dd:81d4/1272c19:dd:c25:c25d:dd:dd:dd:81d5
2362c19:dd:c25:c25d:dd:dd:dd:81d6/1272c19:dd:c25:c25d:dd:dd:dd:81d7
2372c19:dd:c25:c25d:dd:dd:dd:81d8/1272c19:dd:c25:c25d:dd:dd:dd:81d9
2382c19:dd:c25:c25d:dd:dd:dd:81da/1272c19:dd:c25:c25d:dd:dd:dd:81db
2392c19:dd:c25:c25d:dd:dd:dd:81dc/1272c19:dd:c25:c25d:dd:dd:dd:81dd
2402c19:dd:c25:c25d:dd:dd:dd:81de/1272c19:dd:c25:c25d:dd:dd:dd:81df
2412c19:dd:c25:c25d:dd:dd:dd:81e0/1272c19:dd:c25:c25d:dd:dd:dd:81e1
2422c19:dd:c25:c25d:dd:dd:dd:81e2/1272c19:dd:c25:c25d:dd:dd:dd:81e3
2432c19:dd:c25:c25d:dd:dd:dd:81e4/1272c19:dd:c25:c25d:dd:dd:dd:81e5
2442c19:dd:c25:c25d:dd:dd:dd:81e6/1272c19:dd:c25:c25d:dd:dd:dd:81e7
2452c19:dd:c25:c25d:dd:dd:dd:81e8/1272c19:dd:c25:c25d:dd:dd:dd:81e9
2462c19:dd:c25:c25d:dd:dd:dd:81ea/1272c19:dd:c25:c25d:dd:dd:dd:81eb
2472c19:dd:c25:c25d:dd:dd:dd:81ec/1272c19:dd:c25:c25d:dd:dd:dd:81ed
2482c19:dd:c25:c25d:dd:dd:dd:81ee/1272c19:dd:c25:c25d:dd:dd:dd:81ef
2492c19:dd:c25:c25d:dd:dd:dd:81f0/1272c19:dd:c25:c25d:dd:dd:dd:81f1
2502c19:dd:c25:c25d:dd:dd:dd:81f2/1272c19:dd:c25:c25d:dd:dd:dd:81f3
2512c19:dd:c25:c25d:dd:dd:dd:81f4/1272c19:dd:c25:c25d:dd:dd:dd:81f5
2522c19:dd:c25:c25d:dd:dd:dd:81f6/1272c19:dd:c25:c25d:dd:dd:dd:81f7
2532c19:dd:c25:c25d:dd:dd:dd:81f8/1272c19:dd:c25:c25d:dd:dd:dd:81f9
2542c19:dd:c25:c25d:dd:dd:dd:81fa/1272c19:dd:c25:c25d:dd:dd:dd:81fb
2552c19:dd:c25:c25d:dd:dd:dd:81fc/1272c19:dd:c25:c25d:dd:dd:dd:81fd
2562c19:dd:c25:c25d:dd:dd:dd:81fe/1272c19:dd:c25:c25d:dd:dd:dd:81ff

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.