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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:94de:ce00/119
First address
2c19:dd:d9:dd:c25:c25:94de:ce00
Last address
2c19:dd:d9:dd:c25:c25:94de:cfff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:ce00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
e.c.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
f.c.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/127
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:94de:ce00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:ce00/1272c19:dd:d9:dd:c25:c25:94de:ce01
22c19:dd:d9:dd:c25:c25:94de:ce02/1272c19:dd:d9:dd:c25:c25:94de:ce03
32c19:dd:d9:dd:c25:c25:94de:ce04/1272c19:dd:d9:dd:c25:c25:94de:ce05
42c19:dd:d9:dd:c25:c25:94de:ce06/1272c19:dd:d9:dd:c25:c25:94de:ce07
52c19:dd:d9:dd:c25:c25:94de:ce08/1272c19:dd:d9:dd:c25:c25:94de:ce09
62c19:dd:d9:dd:c25:c25:94de:ce0a/1272c19:dd:d9:dd:c25:c25:94de:ce0b
72c19:dd:d9:dd:c25:c25:94de:ce0c/1272c19:dd:d9:dd:c25:c25:94de:ce0d
82c19:dd:d9:dd:c25:c25:94de:ce0e/1272c19:dd:d9:dd:c25:c25:94de:ce0f
92c19:dd:d9:dd:c25:c25:94de:ce10/1272c19:dd:d9:dd:c25:c25:94de:ce11
102c19:dd:d9:dd:c25:c25:94de:ce12/1272c19:dd:d9:dd:c25:c25:94de:ce13
112c19:dd:d9:dd:c25:c25:94de:ce14/1272c19:dd:d9:dd:c25:c25:94de:ce15
122c19:dd:d9:dd:c25:c25:94de:ce16/1272c19:dd:d9:dd:c25:c25:94de:ce17
132c19:dd:d9:dd:c25:c25:94de:ce18/1272c19:dd:d9:dd:c25:c25:94de:ce19
142c19:dd:d9:dd:c25:c25:94de:ce1a/1272c19:dd:d9:dd:c25:c25:94de:ce1b
152c19:dd:d9:dd:c25:c25:94de:ce1c/1272c19:dd:d9:dd:c25:c25:94de:ce1d
162c19:dd:d9:dd:c25:c25:94de:ce1e/1272c19:dd:d9:dd:c25:c25:94de:ce1f
172c19:dd:d9:dd:c25:c25:94de:ce20/1272c19:dd:d9:dd:c25:c25:94de:ce21
182c19:dd:d9:dd:c25:c25:94de:ce22/1272c19:dd:d9:dd:c25:c25:94de:ce23
192c19:dd:d9:dd:c25:c25:94de:ce24/1272c19:dd:d9:dd:c25:c25:94de:ce25
202c19:dd:d9:dd:c25:c25:94de:ce26/1272c19:dd:d9:dd:c25:c25:94de:ce27
212c19:dd:d9:dd:c25:c25:94de:ce28/1272c19:dd:d9:dd:c25:c25:94de:ce29
222c19:dd:d9:dd:c25:c25:94de:ce2a/1272c19:dd:d9:dd:c25:c25:94de:ce2b
232c19:dd:d9:dd:c25:c25:94de:ce2c/1272c19:dd:d9:dd:c25:c25:94de:ce2d
242c19:dd:d9:dd:c25:c25:94de:ce2e/1272c19:dd:d9:dd:c25:c25:94de:ce2f
252c19:dd:d9:dd:c25:c25:94de:ce30/1272c19:dd:d9:dd:c25:c25:94de:ce31
262c19:dd:d9:dd:c25:c25:94de:ce32/1272c19:dd:d9:dd:c25:c25:94de:ce33
272c19:dd:d9:dd:c25:c25:94de:ce34/1272c19:dd:d9:dd:c25:c25:94de:ce35
282c19:dd:d9:dd:c25:c25:94de:ce36/1272c19:dd:d9:dd:c25:c25:94de:ce37
292c19:dd:d9:dd:c25:c25:94de:ce38/1272c19:dd:d9:dd:c25:c25:94de:ce39
302c19:dd:d9:dd:c25:c25:94de:ce3a/1272c19:dd:d9:dd:c25:c25:94de:ce3b
312c19:dd:d9:dd:c25:c25:94de:ce3c/1272c19:dd:d9:dd:c25:c25:94de:ce3d
322c19:dd:d9:dd:c25:c25:94de:ce3e/1272c19:dd:d9:dd:c25:c25:94de:ce3f
332c19:dd:d9:dd:c25:c25:94de:ce40/1272c19:dd:d9:dd:c25:c25:94de:ce41
342c19:dd:d9:dd:c25:c25:94de:ce42/1272c19:dd:d9:dd:c25:c25:94de:ce43
352c19:dd:d9:dd:c25:c25:94de:ce44/1272c19:dd:d9:dd:c25:c25:94de:ce45
362c19:dd:d9:dd:c25:c25:94de:ce46/1272c19:dd:d9:dd:c25:c25:94de:ce47
372c19:dd:d9:dd:c25:c25:94de:ce48/1272c19:dd:d9:dd:c25:c25:94de:ce49
382c19:dd:d9:dd:c25:c25:94de:ce4a/1272c19:dd:d9:dd:c25:c25:94de:ce4b
392c19:dd:d9:dd:c25:c25:94de:ce4c/1272c19:dd:d9:dd:c25:c25:94de:ce4d
402c19:dd:d9:dd:c25:c25:94de:ce4e/1272c19:dd:d9:dd:c25:c25:94de:ce4f
412c19:dd:d9:dd:c25:c25:94de:ce50/1272c19:dd:d9:dd:c25:c25:94de:ce51
422c19:dd:d9:dd:c25:c25:94de:ce52/1272c19:dd:d9:dd:c25:c25:94de:ce53
432c19:dd:d9:dd:c25:c25:94de:ce54/1272c19:dd:d9:dd:c25:c25:94de:ce55
442c19:dd:d9:dd:c25:c25:94de:ce56/1272c19:dd:d9:dd:c25:c25:94de:ce57
452c19:dd:d9:dd:c25:c25:94de:ce58/1272c19:dd:d9:dd:c25:c25:94de:ce59
462c19:dd:d9:dd:c25:c25:94de:ce5a/1272c19:dd:d9:dd:c25:c25:94de:ce5b
472c19:dd:d9:dd:c25:c25:94de:ce5c/1272c19:dd:d9:dd:c25:c25:94de:ce5d
482c19:dd:d9:dd:c25:c25:94de:ce5e/1272c19:dd:d9:dd:c25:c25:94de:ce5f
492c19:dd:d9:dd:c25:c25:94de:ce60/1272c19:dd:d9:dd:c25:c25:94de:ce61
502c19:dd:d9:dd:c25:c25:94de:ce62/1272c19:dd:d9:dd:c25:c25:94de:ce63
512c19:dd:d9:dd:c25:c25:94de:ce64/1272c19:dd:d9:dd:c25:c25:94de:ce65
522c19:dd:d9:dd:c25:c25:94de:ce66/1272c19:dd:d9:dd:c25:c25:94de:ce67
532c19:dd:d9:dd:c25:c25:94de:ce68/1272c19:dd:d9:dd:c25:c25:94de:ce69
542c19:dd:d9:dd:c25:c25:94de:ce6a/1272c19:dd:d9:dd:c25:c25:94de:ce6b
552c19:dd:d9:dd:c25:c25:94de:ce6c/1272c19:dd:d9:dd:c25:c25:94de:ce6d
562c19:dd:d9:dd:c25:c25:94de:ce6e/1272c19:dd:d9:dd:c25:c25:94de:ce6f
572c19:dd:d9:dd:c25:c25:94de:ce70/1272c19:dd:d9:dd:c25:c25:94de:ce71
582c19:dd:d9:dd:c25:c25:94de:ce72/1272c19:dd:d9:dd:c25:c25:94de:ce73
592c19:dd:d9:dd:c25:c25:94de:ce74/1272c19:dd:d9:dd:c25:c25:94de:ce75
602c19:dd:d9:dd:c25:c25:94de:ce76/1272c19:dd:d9:dd:c25:c25:94de:ce77
612c19:dd:d9:dd:c25:c25:94de:ce78/1272c19:dd:d9:dd:c25:c25:94de:ce79
622c19:dd:d9:dd:c25:c25:94de:ce7a/1272c19:dd:d9:dd:c25:c25:94de:ce7b
632c19:dd:d9:dd:c25:c25:94de:ce7c/1272c19:dd:d9:dd:c25:c25:94de:ce7d
642c19:dd:d9:dd:c25:c25:94de:ce7e/1272c19:dd:d9:dd:c25:c25:94de:ce7f
652c19:dd:d9:dd:c25:c25:94de:ce80/1272c19:dd:d9:dd:c25:c25:94de:ce81
662c19:dd:d9:dd:c25:c25:94de:ce82/1272c19:dd:d9:dd:c25:c25:94de:ce83
672c19:dd:d9:dd:c25:c25:94de:ce84/1272c19:dd:d9:dd:c25:c25:94de:ce85
682c19:dd:d9:dd:c25:c25:94de:ce86/1272c19:dd:d9:dd:c25:c25:94de:ce87
692c19:dd:d9:dd:c25:c25:94de:ce88/1272c19:dd:d9:dd:c25:c25:94de:ce89
702c19:dd:d9:dd:c25:c25:94de:ce8a/1272c19:dd:d9:dd:c25:c25:94de:ce8b
712c19:dd:d9:dd:c25:c25:94de:ce8c/1272c19:dd:d9:dd:c25:c25:94de:ce8d
722c19:dd:d9:dd:c25:c25:94de:ce8e/1272c19:dd:d9:dd:c25:c25:94de:ce8f
732c19:dd:d9:dd:c25:c25:94de:ce90/1272c19:dd:d9:dd:c25:c25:94de:ce91
742c19:dd:d9:dd:c25:c25:94de:ce92/1272c19:dd:d9:dd:c25:c25:94de:ce93
752c19:dd:d9:dd:c25:c25:94de:ce94/1272c19:dd:d9:dd:c25:c25:94de:ce95
762c19:dd:d9:dd:c25:c25:94de:ce96/1272c19:dd:d9:dd:c25:c25:94de:ce97
772c19:dd:d9:dd:c25:c25:94de:ce98/1272c19:dd:d9:dd:c25:c25:94de:ce99
782c19:dd:d9:dd:c25:c25:94de:ce9a/1272c19:dd:d9:dd:c25:c25:94de:ce9b
792c19:dd:d9:dd:c25:c25:94de:ce9c/1272c19:dd:d9:dd:c25:c25:94de:ce9d
802c19:dd:d9:dd:c25:c25:94de:ce9e/1272c19:dd:d9:dd:c25:c25:94de:ce9f
812c19:dd:d9:dd:c25:c25:94de:cea0/1272c19:dd:d9:dd:c25:c25:94de:cea1
822c19:dd:d9:dd:c25:c25:94de:cea2/1272c19:dd:d9:dd:c25:c25:94de:cea3
832c19:dd:d9:dd:c25:c25:94de:cea4/1272c19:dd:d9:dd:c25:c25:94de:cea5
842c19:dd:d9:dd:c25:c25:94de:cea6/1272c19:dd:d9:dd:c25:c25:94de:cea7
852c19:dd:d9:dd:c25:c25:94de:cea8/1272c19:dd:d9:dd:c25:c25:94de:cea9
862c19:dd:d9:dd:c25:c25:94de:ceaa/1272c19:dd:d9:dd:c25:c25:94de:ceab
872c19:dd:d9:dd:c25:c25:94de:ceac/1272c19:dd:d9:dd:c25:c25:94de:cead
882c19:dd:d9:dd:c25:c25:94de:ceae/1272c19:dd:d9:dd:c25:c25:94de:ceaf
892c19:dd:d9:dd:c25:c25:94de:ceb0/1272c19:dd:d9:dd:c25:c25:94de:ceb1
902c19:dd:d9:dd:c25:c25:94de:ceb2/1272c19:dd:d9:dd:c25:c25:94de:ceb3
912c19:dd:d9:dd:c25:c25:94de:ceb4/1272c19:dd:d9:dd:c25:c25:94de:ceb5
922c19:dd:d9:dd:c25:c25:94de:ceb6/1272c19:dd:d9:dd:c25:c25:94de:ceb7
932c19:dd:d9:dd:c25:c25:94de:ceb8/1272c19:dd:d9:dd:c25:c25:94de:ceb9
942c19:dd:d9:dd:c25:c25:94de:ceba/1272c19:dd:d9:dd:c25:c25:94de:cebb
952c19:dd:d9:dd:c25:c25:94de:cebc/1272c19:dd:d9:dd:c25:c25:94de:cebd
962c19:dd:d9:dd:c25:c25:94de:cebe/1272c19:dd:d9:dd:c25:c25:94de:cebf
972c19:dd:d9:dd:c25:c25:94de:cec0/1272c19:dd:d9:dd:c25:c25:94de:cec1
982c19:dd:d9:dd:c25:c25:94de:cec2/1272c19:dd:d9:dd:c25:c25:94de:cec3
992c19:dd:d9:dd:c25:c25:94de:cec4/1272c19:dd:d9:dd:c25:c25:94de:cec5
1002c19:dd:d9:dd:c25:c25:94de:cec6/1272c19:dd:d9:dd:c25:c25:94de:cec7
1012c19:dd:d9:dd:c25:c25:94de:cec8/1272c19:dd:d9:dd:c25:c25:94de:cec9
1022c19:dd:d9:dd:c25:c25:94de:ceca/1272c19:dd:d9:dd:c25:c25:94de:cecb
1032c19:dd:d9:dd:c25:c25:94de:cecc/1272c19:dd:d9:dd:c25:c25:94de:cecd
1042c19:dd:d9:dd:c25:c25:94de:cece/1272c19:dd:d9:dd:c25:c25:94de:cecf
1052c19:dd:d9:dd:c25:c25:94de:ced0/1272c19:dd:d9:dd:c25:c25:94de:ced1
1062c19:dd:d9:dd:c25:c25:94de:ced2/1272c19:dd:d9:dd:c25:c25:94de:ced3
1072c19:dd:d9:dd:c25:c25:94de:ced4/1272c19:dd:d9:dd:c25:c25:94de:ced5
1082c19:dd:d9:dd:c25:c25:94de:ced6/1272c19:dd:d9:dd:c25:c25:94de:ced7
1092c19:dd:d9:dd:c25:c25:94de:ced8/1272c19:dd:d9:dd:c25:c25:94de:ced9
1102c19:dd:d9:dd:c25:c25:94de:ceda/1272c19:dd:d9:dd:c25:c25:94de:cedb
1112c19:dd:d9:dd:c25:c25:94de:cedc/1272c19:dd:d9:dd:c25:c25:94de:cedd
1122c19:dd:d9:dd:c25:c25:94de:cede/1272c19:dd:d9:dd:c25:c25:94de:cedf
1132c19:dd:d9:dd:c25:c25:94de:cee0/1272c19:dd:d9:dd:c25:c25:94de:cee1
1142c19:dd:d9:dd:c25:c25:94de:cee2/1272c19:dd:d9:dd:c25:c25:94de:cee3
1152c19:dd:d9:dd:c25:c25:94de:cee4/1272c19:dd:d9:dd:c25:c25:94de:cee5
1162c19:dd:d9:dd:c25:c25:94de:cee6/1272c19:dd:d9:dd:c25:c25:94de:cee7
1172c19:dd:d9:dd:c25:c25:94de:cee8/1272c19:dd:d9:dd:c25:c25:94de:cee9
1182c19:dd:d9:dd:c25:c25:94de:ceea/1272c19:dd:d9:dd:c25:c25:94de:ceeb
1192c19:dd:d9:dd:c25:c25:94de:ceec/1272c19:dd:d9:dd:c25:c25:94de:ceed
1202c19:dd:d9:dd:c25:c25:94de:ceee/1272c19:dd:d9:dd:c25:c25:94de:ceef
1212c19:dd:d9:dd:c25:c25:94de:cef0/1272c19:dd:d9:dd:c25:c25:94de:cef1
1222c19:dd:d9:dd:c25:c25:94de:cef2/1272c19:dd:d9:dd:c25:c25:94de:cef3
1232c19:dd:d9:dd:c25:c25:94de:cef4/1272c19:dd:d9:dd:c25:c25:94de:cef5
1242c19:dd:d9:dd:c25:c25:94de:cef6/1272c19:dd:d9:dd:c25:c25:94de:cef7
1252c19:dd:d9:dd:c25:c25:94de:cef8/1272c19:dd:d9:dd:c25:c25:94de:cef9
1262c19:dd:d9:dd:c25:c25:94de:cefa/1272c19:dd:d9:dd:c25:c25:94de:cefb
1272c19:dd:d9:dd:c25:c25:94de:cefc/1272c19:dd:d9:dd:c25:c25:94de:cefd
1282c19:dd:d9:dd:c25:c25:94de:cefe/1272c19:dd:d9:dd:c25:c25:94de:ceff
1292c19:dd:d9:dd:c25:c25:94de:cf00/1272c19:dd:d9:dd:c25:c25:94de:cf01
1302c19:dd:d9:dd:c25:c25:94de:cf02/1272c19:dd:d9:dd:c25:c25:94de:cf03
1312c19:dd:d9:dd:c25:c25:94de:cf04/1272c19:dd:d9:dd:c25:c25:94de:cf05
1322c19:dd:d9:dd:c25:c25:94de:cf06/1272c19:dd:d9:dd:c25:c25:94de:cf07
1332c19:dd:d9:dd:c25:c25:94de:cf08/1272c19:dd:d9:dd:c25:c25:94de:cf09
1342c19:dd:d9:dd:c25:c25:94de:cf0a/1272c19:dd:d9:dd:c25:c25:94de:cf0b
1352c19:dd:d9:dd:c25:c25:94de:cf0c/1272c19:dd:d9:dd:c25:c25:94de:cf0d
1362c19:dd:d9:dd:c25:c25:94de:cf0e/1272c19:dd:d9:dd:c25:c25:94de:cf0f
1372c19:dd:d9:dd:c25:c25:94de:cf10/1272c19:dd:d9:dd:c25:c25:94de:cf11
1382c19:dd:d9:dd:c25:c25:94de:cf12/1272c19:dd:d9:dd:c25:c25:94de:cf13
1392c19:dd:d9:dd:c25:c25:94de:cf14/1272c19:dd:d9:dd:c25:c25:94de:cf15
1402c19:dd:d9:dd:c25:c25:94de:cf16/1272c19:dd:d9:dd:c25:c25:94de:cf17
1412c19:dd:d9:dd:c25:c25:94de:cf18/1272c19:dd:d9:dd:c25:c25:94de:cf19
1422c19:dd:d9:dd:c25:c25:94de:cf1a/1272c19:dd:d9:dd:c25:c25:94de:cf1b
1432c19:dd:d9:dd:c25:c25:94de:cf1c/1272c19:dd:d9:dd:c25:c25:94de:cf1d
1442c19:dd:d9:dd:c25:c25:94de:cf1e/1272c19:dd:d9:dd:c25:c25:94de:cf1f
1452c19:dd:d9:dd:c25:c25:94de:cf20/1272c19:dd:d9:dd:c25:c25:94de:cf21
1462c19:dd:d9:dd:c25:c25:94de:cf22/1272c19:dd:d9:dd:c25:c25:94de:cf23
1472c19:dd:d9:dd:c25:c25:94de:cf24/1272c19:dd:d9:dd:c25:c25:94de:cf25
1482c19:dd:d9:dd:c25:c25:94de:cf26/1272c19:dd:d9:dd:c25:c25:94de:cf27
1492c19:dd:d9:dd:c25:c25:94de:cf28/1272c19:dd:d9:dd:c25:c25:94de:cf29
1502c19:dd:d9:dd:c25:c25:94de:cf2a/1272c19:dd:d9:dd:c25:c25:94de:cf2b
1512c19:dd:d9:dd:c25:c25:94de:cf2c/1272c19:dd:d9:dd:c25:c25:94de:cf2d
1522c19:dd:d9:dd:c25:c25:94de:cf2e/1272c19:dd:d9:dd:c25:c25:94de:cf2f
1532c19:dd:d9:dd:c25:c25:94de:cf30/1272c19:dd:d9:dd:c25:c25:94de:cf31
1542c19:dd:d9:dd:c25:c25:94de:cf32/1272c19:dd:d9:dd:c25:c25:94de:cf33
1552c19:dd:d9:dd:c25:c25:94de:cf34/1272c19:dd:d9:dd:c25:c25:94de:cf35
1562c19:dd:d9:dd:c25:c25:94de:cf36/1272c19:dd:d9:dd:c25:c25:94de:cf37
1572c19:dd:d9:dd:c25:c25:94de:cf38/1272c19:dd:d9:dd:c25:c25:94de:cf39
1582c19:dd:d9:dd:c25:c25:94de:cf3a/1272c19:dd:d9:dd:c25:c25:94de:cf3b
1592c19:dd:d9:dd:c25:c25:94de:cf3c/1272c19:dd:d9:dd:c25:c25:94de:cf3d
1602c19:dd:d9:dd:c25:c25:94de:cf3e/1272c19:dd:d9:dd:c25:c25:94de:cf3f
1612c19:dd:d9:dd:c25:c25:94de:cf40/1272c19:dd:d9:dd:c25:c25:94de:cf41
1622c19:dd:d9:dd:c25:c25:94de:cf42/1272c19:dd:d9:dd:c25:c25:94de:cf43
1632c19:dd:d9:dd:c25:c25:94de:cf44/1272c19:dd:d9:dd:c25:c25:94de:cf45
1642c19:dd:d9:dd:c25:c25:94de:cf46/1272c19:dd:d9:dd:c25:c25:94de:cf47
1652c19:dd:d9:dd:c25:c25:94de:cf48/1272c19:dd:d9:dd:c25:c25:94de:cf49
1662c19:dd:d9:dd:c25:c25:94de:cf4a/1272c19:dd:d9:dd:c25:c25:94de:cf4b
1672c19:dd:d9:dd:c25:c25:94de:cf4c/1272c19:dd:d9:dd:c25:c25:94de:cf4d
1682c19:dd:d9:dd:c25:c25:94de:cf4e/1272c19:dd:d9:dd:c25:c25:94de:cf4f
1692c19:dd:d9:dd:c25:c25:94de:cf50/1272c19:dd:d9:dd:c25:c25:94de:cf51
1702c19:dd:d9:dd:c25:c25:94de:cf52/1272c19:dd:d9:dd:c25:c25:94de:cf53
1712c19:dd:d9:dd:c25:c25:94de:cf54/1272c19:dd:d9:dd:c25:c25:94de:cf55
1722c19:dd:d9:dd:c25:c25:94de:cf56/1272c19:dd:d9:dd:c25:c25:94de:cf57
1732c19:dd:d9:dd:c25:c25:94de:cf58/1272c19:dd:d9:dd:c25:c25:94de:cf59
1742c19:dd:d9:dd:c25:c25:94de:cf5a/1272c19:dd:d9:dd:c25:c25:94de:cf5b
1752c19:dd:d9:dd:c25:c25:94de:cf5c/1272c19:dd:d9:dd:c25:c25:94de:cf5d
1762c19:dd:d9:dd:c25:c25:94de:cf5e/1272c19:dd:d9:dd:c25:c25:94de:cf5f
1772c19:dd:d9:dd:c25:c25:94de:cf60/1272c19:dd:d9:dd:c25:c25:94de:cf61
1782c19:dd:d9:dd:c25:c25:94de:cf62/1272c19:dd:d9:dd:c25:c25:94de:cf63
1792c19:dd:d9:dd:c25:c25:94de:cf64/1272c19:dd:d9:dd:c25:c25:94de:cf65
1802c19:dd:d9:dd:c25:c25:94de:cf66/1272c19:dd:d9:dd:c25:c25:94de:cf67
1812c19:dd:d9:dd:c25:c25:94de:cf68/1272c19:dd:d9:dd:c25:c25:94de:cf69
1822c19:dd:d9:dd:c25:c25:94de:cf6a/1272c19:dd:d9:dd:c25:c25:94de:cf6b
1832c19:dd:d9:dd:c25:c25:94de:cf6c/1272c19:dd:d9:dd:c25:c25:94de:cf6d
1842c19:dd:d9:dd:c25:c25:94de:cf6e/1272c19:dd:d9:dd:c25:c25:94de:cf6f
1852c19:dd:d9:dd:c25:c25:94de:cf70/1272c19:dd:d9:dd:c25:c25:94de:cf71
1862c19:dd:d9:dd:c25:c25:94de:cf72/1272c19:dd:d9:dd:c25:c25:94de:cf73
1872c19:dd:d9:dd:c25:c25:94de:cf74/1272c19:dd:d9:dd:c25:c25:94de:cf75
1882c19:dd:d9:dd:c25:c25:94de:cf76/1272c19:dd:d9:dd:c25:c25:94de:cf77
1892c19:dd:d9:dd:c25:c25:94de:cf78/1272c19:dd:d9:dd:c25:c25:94de:cf79
1902c19:dd:d9:dd:c25:c25:94de:cf7a/1272c19:dd:d9:dd:c25:c25:94de:cf7b
1912c19:dd:d9:dd:c25:c25:94de:cf7c/1272c19:dd:d9:dd:c25:c25:94de:cf7d
1922c19:dd:d9:dd:c25:c25:94de:cf7e/1272c19:dd:d9:dd:c25:c25:94de:cf7f
1932c19:dd:d9:dd:c25:c25:94de:cf80/1272c19:dd:d9:dd:c25:c25:94de:cf81
1942c19:dd:d9:dd:c25:c25:94de:cf82/1272c19:dd:d9:dd:c25:c25:94de:cf83
1952c19:dd:d9:dd:c25:c25:94de:cf84/1272c19:dd:d9:dd:c25:c25:94de:cf85
1962c19:dd:d9:dd:c25:c25:94de:cf86/1272c19:dd:d9:dd:c25:c25:94de:cf87
1972c19:dd:d9:dd:c25:c25:94de:cf88/1272c19:dd:d9:dd:c25:c25:94de:cf89
1982c19:dd:d9:dd:c25:c25:94de:cf8a/1272c19:dd:d9:dd:c25:c25:94de:cf8b
1992c19:dd:d9:dd:c25:c25:94de:cf8c/1272c19:dd:d9:dd:c25:c25:94de:cf8d
2002c19:dd:d9:dd:c25:c25:94de:cf8e/1272c19:dd:d9:dd:c25:c25:94de:cf8f
2012c19:dd:d9:dd:c25:c25:94de:cf90/1272c19:dd:d9:dd:c25:c25:94de:cf91
2022c19:dd:d9:dd:c25:c25:94de:cf92/1272c19:dd:d9:dd:c25:c25:94de:cf93
2032c19:dd:d9:dd:c25:c25:94de:cf94/1272c19:dd:d9:dd:c25:c25:94de:cf95
2042c19:dd:d9:dd:c25:c25:94de:cf96/1272c19:dd:d9:dd:c25:c25:94de:cf97
2052c19:dd:d9:dd:c25:c25:94de:cf98/1272c19:dd:d9:dd:c25:c25:94de:cf99
2062c19:dd:d9:dd:c25:c25:94de:cf9a/1272c19:dd:d9:dd:c25:c25:94de:cf9b
2072c19:dd:d9:dd:c25:c25:94de:cf9c/1272c19:dd:d9:dd:c25:c25:94de:cf9d
2082c19:dd:d9:dd:c25:c25:94de:cf9e/1272c19:dd:d9:dd:c25:c25:94de:cf9f
2092c19:dd:d9:dd:c25:c25:94de:cfa0/1272c19:dd:d9:dd:c25:c25:94de:cfa1
2102c19:dd:d9:dd:c25:c25:94de:cfa2/1272c19:dd:d9:dd:c25:c25:94de:cfa3
2112c19:dd:d9:dd:c25:c25:94de:cfa4/1272c19:dd:d9:dd:c25:c25:94de:cfa5
2122c19:dd:d9:dd:c25:c25:94de:cfa6/1272c19:dd:d9:dd:c25:c25:94de:cfa7
2132c19:dd:d9:dd:c25:c25:94de:cfa8/1272c19:dd:d9:dd:c25:c25:94de:cfa9
2142c19:dd:d9:dd:c25:c25:94de:cfaa/1272c19:dd:d9:dd:c25:c25:94de:cfab
2152c19:dd:d9:dd:c25:c25:94de:cfac/1272c19:dd:d9:dd:c25:c25:94de:cfad
2162c19:dd:d9:dd:c25:c25:94de:cfae/1272c19:dd:d9:dd:c25:c25:94de:cfaf
2172c19:dd:d9:dd:c25:c25:94de:cfb0/1272c19:dd:d9:dd:c25:c25:94de:cfb1
2182c19:dd:d9:dd:c25:c25:94de:cfb2/1272c19:dd:d9:dd:c25:c25:94de:cfb3
2192c19:dd:d9:dd:c25:c25:94de:cfb4/1272c19:dd:d9:dd:c25:c25:94de:cfb5
2202c19:dd:d9:dd:c25:c25:94de:cfb6/1272c19:dd:d9:dd:c25:c25:94de:cfb7
2212c19:dd:d9:dd:c25:c25:94de:cfb8/1272c19:dd:d9:dd:c25:c25:94de:cfb9
2222c19:dd:d9:dd:c25:c25:94de:cfba/1272c19:dd:d9:dd:c25:c25:94de:cfbb
2232c19:dd:d9:dd:c25:c25:94de:cfbc/1272c19:dd:d9:dd:c25:c25:94de:cfbd
2242c19:dd:d9:dd:c25:c25:94de:cfbe/1272c19:dd:d9:dd:c25:c25:94de:cfbf
2252c19:dd:d9:dd:c25:c25:94de:cfc0/1272c19:dd:d9:dd:c25:c25:94de:cfc1
2262c19:dd:d9:dd:c25:c25:94de:cfc2/1272c19:dd:d9:dd:c25:c25:94de:cfc3
2272c19:dd:d9:dd:c25:c25:94de:cfc4/1272c19:dd:d9:dd:c25:c25:94de:cfc5
2282c19:dd:d9:dd:c25:c25:94de:cfc6/1272c19:dd:d9:dd:c25:c25:94de:cfc7
2292c19:dd:d9:dd:c25:c25:94de:cfc8/1272c19:dd:d9:dd:c25:c25:94de:cfc9
2302c19:dd:d9:dd:c25:c25:94de:cfca/1272c19:dd:d9:dd:c25:c25:94de:cfcb
2312c19:dd:d9:dd:c25:c25:94de:cfcc/1272c19:dd:d9:dd:c25:c25:94de:cfcd
2322c19:dd:d9:dd:c25:c25:94de:cfce/1272c19:dd:d9:dd:c25:c25:94de:cfcf
2332c19:dd:d9:dd:c25:c25:94de:cfd0/1272c19:dd:d9:dd:c25:c25:94de:cfd1
2342c19:dd:d9:dd:c25:c25:94de:cfd2/1272c19:dd:d9:dd:c25:c25:94de:cfd3
2352c19:dd:d9:dd:c25:c25:94de:cfd4/1272c19:dd:d9:dd:c25:c25:94de:cfd5
2362c19:dd:d9:dd:c25:c25:94de:cfd6/1272c19:dd:d9:dd:c25:c25:94de:cfd7
2372c19:dd:d9:dd:c25:c25:94de:cfd8/1272c19:dd:d9:dd:c25:c25:94de:cfd9
2382c19:dd:d9:dd:c25:c25:94de:cfda/1272c19:dd:d9:dd:c25:c25:94de:cfdb
2392c19:dd:d9:dd:c25:c25:94de:cfdc/1272c19:dd:d9:dd:c25:c25:94de:cfdd
2402c19:dd:d9:dd:c25:c25:94de:cfde/1272c19:dd:d9:dd:c25:c25:94de:cfdf
2412c19:dd:d9:dd:c25:c25:94de:cfe0/1272c19:dd:d9:dd:c25:c25:94de:cfe1
2422c19:dd:d9:dd:c25:c25:94de:cfe2/1272c19:dd:d9:dd:c25:c25:94de:cfe3
2432c19:dd:d9:dd:c25:c25:94de:cfe4/1272c19:dd:d9:dd:c25:c25:94de:cfe5
2442c19:dd:d9:dd:c25:c25:94de:cfe6/1272c19:dd:d9:dd:c25:c25:94de:cfe7
2452c19:dd:d9:dd:c25:c25:94de:cfe8/1272c19:dd:d9:dd:c25:c25:94de:cfe9
2462c19:dd:d9:dd:c25:c25:94de:cfea/1272c19:dd:d9:dd:c25:c25:94de:cfeb
2472c19:dd:d9:dd:c25:c25:94de:cfec/1272c19:dd:d9:dd:c25:c25:94de:cfed
2482c19:dd:d9:dd:c25:c25:94de:cfee/1272c19:dd:d9:dd:c25:c25:94de:cfef
2492c19:dd:d9:dd:c25:c25:94de:cff0/1272c19:dd:d9:dd:c25:c25:94de:cff1
2502c19:dd:d9:dd:c25:c25:94de:cff2/1272c19:dd:d9:dd:c25:c25:94de:cff3
2512c19:dd:d9:dd:c25:c25:94de:cff4/1272c19:dd:d9:dd:c25:c25:94de:cff5
2522c19:dd:d9:dd:c25:c25:94de:cff6/1272c19:dd:d9:dd:c25:c25:94de:cff7
2532c19:dd:d9:dd:c25:c25:94de:cff8/1272c19:dd:d9:dd:c25:c25:94de:cff9
2542c19:dd:d9:dd:c25:c25:94de:cffa/1272c19:dd:d9:dd:c25:c25:94de:cffb
2552c19:dd:d9:dd:c25:c25:94de:cffc/1272c19:dd:d9:dd:c25:c25:94de:cffd
2562c19:dd:d9:dd:c25:c25:94de:cffe/1272c19:dd:d9:dd:c25:c25:94de:cfff

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.