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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:ee00/119
First address
2c19:dd:d9:dd:c25:c25:94de:ee00
Last address
2c19:dd:d9:dd:c25:c25:94de:efff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:ee00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
e.e.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.e.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:ee00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:ee00/1272c19:dd:d9:dd:c25:c25:94de:ee01
22c19:dd:d9:dd:c25:c25:94de:ee02/1272c19:dd:d9:dd:c25:c25:94de:ee03
32c19:dd:d9:dd:c25:c25:94de:ee04/1272c19:dd:d9:dd:c25:c25:94de:ee05
42c19:dd:d9:dd:c25:c25:94de:ee06/1272c19:dd:d9:dd:c25:c25:94de:ee07
52c19:dd:d9:dd:c25:c25:94de:ee08/1272c19:dd:d9:dd:c25:c25:94de:ee09
62c19:dd:d9:dd:c25:c25:94de:ee0a/1272c19:dd:d9:dd:c25:c25:94de:ee0b
72c19:dd:d9:dd:c25:c25:94de:ee0c/1272c19:dd:d9:dd:c25:c25:94de:ee0d
82c19:dd:d9:dd:c25:c25:94de:ee0e/1272c19:dd:d9:dd:c25:c25:94de:ee0f
92c19:dd:d9:dd:c25:c25:94de:ee10/1272c19:dd:d9:dd:c25:c25:94de:ee11
102c19:dd:d9:dd:c25:c25:94de:ee12/1272c19:dd:d9:dd:c25:c25:94de:ee13
112c19:dd:d9:dd:c25:c25:94de:ee14/1272c19:dd:d9:dd:c25:c25:94de:ee15
122c19:dd:d9:dd:c25:c25:94de:ee16/1272c19:dd:d9:dd:c25:c25:94de:ee17
132c19:dd:d9:dd:c25:c25:94de:ee18/1272c19:dd:d9:dd:c25:c25:94de:ee19
142c19:dd:d9:dd:c25:c25:94de:ee1a/1272c19:dd:d9:dd:c25:c25:94de:ee1b
152c19:dd:d9:dd:c25:c25:94de:ee1c/1272c19:dd:d9:dd:c25:c25:94de:ee1d
162c19:dd:d9:dd:c25:c25:94de:ee1e/1272c19:dd:d9:dd:c25:c25:94de:ee1f
172c19:dd:d9:dd:c25:c25:94de:ee20/1272c19:dd:d9:dd:c25:c25:94de:ee21
182c19:dd:d9:dd:c25:c25:94de:ee22/1272c19:dd:d9:dd:c25:c25:94de:ee23
192c19:dd:d9:dd:c25:c25:94de:ee24/1272c19:dd:d9:dd:c25:c25:94de:ee25
202c19:dd:d9:dd:c25:c25:94de:ee26/1272c19:dd:d9:dd:c25:c25:94de:ee27
212c19:dd:d9:dd:c25:c25:94de:ee28/1272c19:dd:d9:dd:c25:c25:94de:ee29
222c19:dd:d9:dd:c25:c25:94de:ee2a/1272c19:dd:d9:dd:c25:c25:94de:ee2b
232c19:dd:d9:dd:c25:c25:94de:ee2c/1272c19:dd:d9:dd:c25:c25:94de:ee2d
242c19:dd:d9:dd:c25:c25:94de:ee2e/1272c19:dd:d9:dd:c25:c25:94de:ee2f
252c19:dd:d9:dd:c25:c25:94de:ee30/1272c19:dd:d9:dd:c25:c25:94de:ee31
262c19:dd:d9:dd:c25:c25:94de:ee32/1272c19:dd:d9:dd:c25:c25:94de:ee33
272c19:dd:d9:dd:c25:c25:94de:ee34/1272c19:dd:d9:dd:c25:c25:94de:ee35
282c19:dd:d9:dd:c25:c25:94de:ee36/1272c19:dd:d9:dd:c25:c25:94de:ee37
292c19:dd:d9:dd:c25:c25:94de:ee38/1272c19:dd:d9:dd:c25:c25:94de:ee39
302c19:dd:d9:dd:c25:c25:94de:ee3a/1272c19:dd:d9:dd:c25:c25:94de:ee3b
312c19:dd:d9:dd:c25:c25:94de:ee3c/1272c19:dd:d9:dd:c25:c25:94de:ee3d
322c19:dd:d9:dd:c25:c25:94de:ee3e/1272c19:dd:d9:dd:c25:c25:94de:ee3f
332c19:dd:d9:dd:c25:c25:94de:ee40/1272c19:dd:d9:dd:c25:c25:94de:ee41
342c19:dd:d9:dd:c25:c25:94de:ee42/1272c19:dd:d9:dd:c25:c25:94de:ee43
352c19:dd:d9:dd:c25:c25:94de:ee44/1272c19:dd:d9:dd:c25:c25:94de:ee45
362c19:dd:d9:dd:c25:c25:94de:ee46/1272c19:dd:d9:dd:c25:c25:94de:ee47
372c19:dd:d9:dd:c25:c25:94de:ee48/1272c19:dd:d9:dd:c25:c25:94de:ee49
382c19:dd:d9:dd:c25:c25:94de:ee4a/1272c19:dd:d9:dd:c25:c25:94de:ee4b
392c19:dd:d9:dd:c25:c25:94de:ee4c/1272c19:dd:d9:dd:c25:c25:94de:ee4d
402c19:dd:d9:dd:c25:c25:94de:ee4e/1272c19:dd:d9:dd:c25:c25:94de:ee4f
412c19:dd:d9:dd:c25:c25:94de:ee50/1272c19:dd:d9:dd:c25:c25:94de:ee51
422c19:dd:d9:dd:c25:c25:94de:ee52/1272c19:dd:d9:dd:c25:c25:94de:ee53
432c19:dd:d9:dd:c25:c25:94de:ee54/1272c19:dd:d9:dd:c25:c25:94de:ee55
442c19:dd:d9:dd:c25:c25:94de:ee56/1272c19:dd:d9:dd:c25:c25:94de:ee57
452c19:dd:d9:dd:c25:c25:94de:ee58/1272c19:dd:d9:dd:c25:c25:94de:ee59
462c19:dd:d9:dd:c25:c25:94de:ee5a/1272c19:dd:d9:dd:c25:c25:94de:ee5b
472c19:dd:d9:dd:c25:c25:94de:ee5c/1272c19:dd:d9:dd:c25:c25:94de:ee5d
482c19:dd:d9:dd:c25:c25:94de:ee5e/1272c19:dd:d9:dd:c25:c25:94de:ee5f
492c19:dd:d9:dd:c25:c25:94de:ee60/1272c19:dd:d9:dd:c25:c25:94de:ee61
502c19:dd:d9:dd:c25:c25:94de:ee62/1272c19:dd:d9:dd:c25:c25:94de:ee63
512c19:dd:d9:dd:c25:c25:94de:ee64/1272c19:dd:d9:dd:c25:c25:94de:ee65
522c19:dd:d9:dd:c25:c25:94de:ee66/1272c19:dd:d9:dd:c25:c25:94de:ee67
532c19:dd:d9:dd:c25:c25:94de:ee68/1272c19:dd:d9:dd:c25:c25:94de:ee69
542c19:dd:d9:dd:c25:c25:94de:ee6a/1272c19:dd:d9:dd:c25:c25:94de:ee6b
552c19:dd:d9:dd:c25:c25:94de:ee6c/1272c19:dd:d9:dd:c25:c25:94de:ee6d
562c19:dd:d9:dd:c25:c25:94de:ee6e/1272c19:dd:d9:dd:c25:c25:94de:ee6f
572c19:dd:d9:dd:c25:c25:94de:ee70/1272c19:dd:d9:dd:c25:c25:94de:ee71
582c19:dd:d9:dd:c25:c25:94de:ee72/1272c19:dd:d9:dd:c25:c25:94de:ee73
592c19:dd:d9:dd:c25:c25:94de:ee74/1272c19:dd:d9:dd:c25:c25:94de:ee75
602c19:dd:d9:dd:c25:c25:94de:ee76/1272c19:dd:d9:dd:c25:c25:94de:ee77
612c19:dd:d9:dd:c25:c25:94de:ee78/1272c19:dd:d9:dd:c25:c25:94de:ee79
622c19:dd:d9:dd:c25:c25:94de:ee7a/1272c19:dd:d9:dd:c25:c25:94de:ee7b
632c19:dd:d9:dd:c25:c25:94de:ee7c/1272c19:dd:d9:dd:c25:c25:94de:ee7d
642c19:dd:d9:dd:c25:c25:94de:ee7e/1272c19:dd:d9:dd:c25:c25:94de:ee7f
652c19:dd:d9:dd:c25:c25:94de:ee80/1272c19:dd:d9:dd:c25:c25:94de:ee81
662c19:dd:d9:dd:c25:c25:94de:ee82/1272c19:dd:d9:dd:c25:c25:94de:ee83
672c19:dd:d9:dd:c25:c25:94de:ee84/1272c19:dd:d9:dd:c25:c25:94de:ee85
682c19:dd:d9:dd:c25:c25:94de:ee86/1272c19:dd:d9:dd:c25:c25:94de:ee87
692c19:dd:d9:dd:c25:c25:94de:ee88/1272c19:dd:d9:dd:c25:c25:94de:ee89
702c19:dd:d9:dd:c25:c25:94de:ee8a/1272c19:dd:d9:dd:c25:c25:94de:ee8b
712c19:dd:d9:dd:c25:c25:94de:ee8c/1272c19:dd:d9:dd:c25:c25:94de:ee8d
722c19:dd:d9:dd:c25:c25:94de:ee8e/1272c19:dd:d9:dd:c25:c25:94de:ee8f
732c19:dd:d9:dd:c25:c25:94de:ee90/1272c19:dd:d9:dd:c25:c25:94de:ee91
742c19:dd:d9:dd:c25:c25:94de:ee92/1272c19:dd:d9:dd:c25:c25:94de:ee93
752c19:dd:d9:dd:c25:c25:94de:ee94/1272c19:dd:d9:dd:c25:c25:94de:ee95
762c19:dd:d9:dd:c25:c25:94de:ee96/1272c19:dd:d9:dd:c25:c25:94de:ee97
772c19:dd:d9:dd:c25:c25:94de:ee98/1272c19:dd:d9:dd:c25:c25:94de:ee99
782c19:dd:d9:dd:c25:c25:94de:ee9a/1272c19:dd:d9:dd:c25:c25:94de:ee9b
792c19:dd:d9:dd:c25:c25:94de:ee9c/1272c19:dd:d9:dd:c25:c25:94de:ee9d
802c19:dd:d9:dd:c25:c25:94de:ee9e/1272c19:dd:d9:dd:c25:c25:94de:ee9f
812c19:dd:d9:dd:c25:c25:94de:eea0/1272c19:dd:d9:dd:c25:c25:94de:eea1
822c19:dd:d9:dd:c25:c25:94de:eea2/1272c19:dd:d9:dd:c25:c25:94de:eea3
832c19:dd:d9:dd:c25:c25:94de:eea4/1272c19:dd:d9:dd:c25:c25:94de:eea5
842c19:dd:d9:dd:c25:c25:94de:eea6/1272c19:dd:d9:dd:c25:c25:94de:eea7
852c19:dd:d9:dd:c25:c25:94de:eea8/1272c19:dd:d9:dd:c25:c25:94de:eea9
862c19:dd:d9:dd:c25:c25:94de:eeaa/1272c19:dd:d9:dd:c25:c25:94de:eeab
872c19:dd:d9:dd:c25:c25:94de:eeac/1272c19:dd:d9:dd:c25:c25:94de:eead
882c19:dd:d9:dd:c25:c25:94de:eeae/1272c19:dd:d9:dd:c25:c25:94de:eeaf
892c19:dd:d9:dd:c25:c25:94de:eeb0/1272c19:dd:d9:dd:c25:c25:94de:eeb1
902c19:dd:d9:dd:c25:c25:94de:eeb2/1272c19:dd:d9:dd:c25:c25:94de:eeb3
912c19:dd:d9:dd:c25:c25:94de:eeb4/1272c19:dd:d9:dd:c25:c25:94de:eeb5
922c19:dd:d9:dd:c25:c25:94de:eeb6/1272c19:dd:d9:dd:c25:c25:94de:eeb7
932c19:dd:d9:dd:c25:c25:94de:eeb8/1272c19:dd:d9:dd:c25:c25:94de:eeb9
942c19:dd:d9:dd:c25:c25:94de:eeba/1272c19:dd:d9:dd:c25:c25:94de:eebb
952c19:dd:d9:dd:c25:c25:94de:eebc/1272c19:dd:d9:dd:c25:c25:94de:eebd
962c19:dd:d9:dd:c25:c25:94de:eebe/1272c19:dd:d9:dd:c25:c25:94de:eebf
972c19:dd:d9:dd:c25:c25:94de:eec0/1272c19:dd:d9:dd:c25:c25:94de:eec1
982c19:dd:d9:dd:c25:c25:94de:eec2/1272c19:dd:d9:dd:c25:c25:94de:eec3
992c19:dd:d9:dd:c25:c25:94de:eec4/1272c19:dd:d9:dd:c25:c25:94de:eec5
1002c19:dd:d9:dd:c25:c25:94de:eec6/1272c19:dd:d9:dd:c25:c25:94de:eec7
1012c19:dd:d9:dd:c25:c25:94de:eec8/1272c19:dd:d9:dd:c25:c25:94de:eec9
1022c19:dd:d9:dd:c25:c25:94de:eeca/1272c19:dd:d9:dd:c25:c25:94de:eecb
1032c19:dd:d9:dd:c25:c25:94de:eecc/1272c19:dd:d9:dd:c25:c25:94de:eecd
1042c19:dd:d9:dd:c25:c25:94de:eece/1272c19:dd:d9:dd:c25:c25:94de:eecf
1052c19:dd:d9:dd:c25:c25:94de:eed0/1272c19:dd:d9:dd:c25:c25:94de:eed1
1062c19:dd:d9:dd:c25:c25:94de:eed2/1272c19:dd:d9:dd:c25:c25:94de:eed3
1072c19:dd:d9:dd:c25:c25:94de:eed4/1272c19:dd:d9:dd:c25:c25:94de:eed5
1082c19:dd:d9:dd:c25:c25:94de:eed6/1272c19:dd:d9:dd:c25:c25:94de:eed7
1092c19:dd:d9:dd:c25:c25:94de:eed8/1272c19:dd:d9:dd:c25:c25:94de:eed9
1102c19:dd:d9:dd:c25:c25:94de:eeda/1272c19:dd:d9:dd:c25:c25:94de:eedb
1112c19:dd:d9:dd:c25:c25:94de:eedc/1272c19:dd:d9:dd:c25:c25:94de:eedd
1122c19:dd:d9:dd:c25:c25:94de:eede/1272c19:dd:d9:dd:c25:c25:94de:eedf
1132c19:dd:d9:dd:c25:c25:94de:eee0/1272c19:dd:d9:dd:c25:c25:94de:eee1
1142c19:dd:d9:dd:c25:c25:94de:eee2/1272c19:dd:d9:dd:c25:c25:94de:eee3
1152c19:dd:d9:dd:c25:c25:94de:eee4/1272c19:dd:d9:dd:c25:c25:94de:eee5
1162c19:dd:d9:dd:c25:c25:94de:eee6/1272c19:dd:d9:dd:c25:c25:94de:eee7
1172c19:dd:d9:dd:c25:c25:94de:eee8/1272c19:dd:d9:dd:c25:c25:94de:eee9
1182c19:dd:d9:dd:c25:c25:94de:eeea/1272c19:dd:d9:dd:c25:c25:94de:eeeb
1192c19:dd:d9:dd:c25:c25:94de:eeec/1272c19:dd:d9:dd:c25:c25:94de:eeed
1202c19:dd:d9:dd:c25:c25:94de:eeee/1272c19:dd:d9:dd:c25:c25:94de:eeef
1212c19:dd:d9:dd:c25:c25:94de:eef0/1272c19:dd:d9:dd:c25:c25:94de:eef1
1222c19:dd:d9:dd:c25:c25:94de:eef2/1272c19:dd:d9:dd:c25:c25:94de:eef3
1232c19:dd:d9:dd:c25:c25:94de:eef4/1272c19:dd:d9:dd:c25:c25:94de:eef5
1242c19:dd:d9:dd:c25:c25:94de:eef6/1272c19:dd:d9:dd:c25:c25:94de:eef7
1252c19:dd:d9:dd:c25:c25:94de:eef8/1272c19:dd:d9:dd:c25:c25:94de:eef9
1262c19:dd:d9:dd:c25:c25:94de:eefa/1272c19:dd:d9:dd:c25:c25:94de:eefb
1272c19:dd:d9:dd:c25:c25:94de:eefc/1272c19:dd:d9:dd:c25:c25:94de:eefd
1282c19:dd:d9:dd:c25:c25:94de:eefe/1272c19:dd:d9:dd:c25:c25:94de:eeff
1292c19:dd:d9:dd:c25:c25:94de:ef00/1272c19:dd:d9:dd:c25:c25:94de:ef01
1302c19:dd:d9:dd:c25:c25:94de:ef02/1272c19:dd:d9:dd:c25:c25:94de:ef03
1312c19:dd:d9:dd:c25:c25:94de:ef04/1272c19:dd:d9:dd:c25:c25:94de:ef05
1322c19:dd:d9:dd:c25:c25:94de:ef06/1272c19:dd:d9:dd:c25:c25:94de:ef07
1332c19:dd:d9:dd:c25:c25:94de:ef08/1272c19:dd:d9:dd:c25:c25:94de:ef09
1342c19:dd:d9:dd:c25:c25:94de:ef0a/1272c19:dd:d9:dd:c25:c25:94de:ef0b
1352c19:dd:d9:dd:c25:c25:94de:ef0c/1272c19:dd:d9:dd:c25:c25:94de:ef0d
1362c19:dd:d9:dd:c25:c25:94de:ef0e/1272c19:dd:d9:dd:c25:c25:94de:ef0f
1372c19:dd:d9:dd:c25:c25:94de:ef10/1272c19:dd:d9:dd:c25:c25:94de:ef11
1382c19:dd:d9:dd:c25:c25:94de:ef12/1272c19:dd:d9:dd:c25:c25:94de:ef13
1392c19:dd:d9:dd:c25:c25:94de:ef14/1272c19:dd:d9:dd:c25:c25:94de:ef15
1402c19:dd:d9:dd:c25:c25:94de:ef16/1272c19:dd:d9:dd:c25:c25:94de:ef17
1412c19:dd:d9:dd:c25:c25:94de:ef18/1272c19:dd:d9:dd:c25:c25:94de:ef19
1422c19:dd:d9:dd:c25:c25:94de:ef1a/1272c19:dd:d9:dd:c25:c25:94de:ef1b
1432c19:dd:d9:dd:c25:c25:94de:ef1c/1272c19:dd:d9:dd:c25:c25:94de:ef1d
1442c19:dd:d9:dd:c25:c25:94de:ef1e/1272c19:dd:d9:dd:c25:c25:94de:ef1f
1452c19:dd:d9:dd:c25:c25:94de:ef20/1272c19:dd:d9:dd:c25:c25:94de:ef21
1462c19:dd:d9:dd:c25:c25:94de:ef22/1272c19:dd:d9:dd:c25:c25:94de:ef23
1472c19:dd:d9:dd:c25:c25:94de:ef24/1272c19:dd:d9:dd:c25:c25:94de:ef25
1482c19:dd:d9:dd:c25:c25:94de:ef26/1272c19:dd:d9:dd:c25:c25:94de:ef27
1492c19:dd:d9:dd:c25:c25:94de:ef28/1272c19:dd:d9:dd:c25:c25:94de:ef29
1502c19:dd:d9:dd:c25:c25:94de:ef2a/1272c19:dd:d9:dd:c25:c25:94de:ef2b
1512c19:dd:d9:dd:c25:c25:94de:ef2c/1272c19:dd:d9:dd:c25:c25:94de:ef2d
1522c19:dd:d9:dd:c25:c25:94de:ef2e/1272c19:dd:d9:dd:c25:c25:94de:ef2f
1532c19:dd:d9:dd:c25:c25:94de:ef30/1272c19:dd:d9:dd:c25:c25:94de:ef31
1542c19:dd:d9:dd:c25:c25:94de:ef32/1272c19:dd:d9:dd:c25:c25:94de:ef33
1552c19:dd:d9:dd:c25:c25:94de:ef34/1272c19:dd:d9:dd:c25:c25:94de:ef35
1562c19:dd:d9:dd:c25:c25:94de:ef36/1272c19:dd:d9:dd:c25:c25:94de:ef37
1572c19:dd:d9:dd:c25:c25:94de:ef38/1272c19:dd:d9:dd:c25:c25:94de:ef39
1582c19:dd:d9:dd:c25:c25:94de:ef3a/1272c19:dd:d9:dd:c25:c25:94de:ef3b
1592c19:dd:d9:dd:c25:c25:94de:ef3c/1272c19:dd:d9:dd:c25:c25:94de:ef3d
1602c19:dd:d9:dd:c25:c25:94de:ef3e/1272c19:dd:d9:dd:c25:c25:94de:ef3f
1612c19:dd:d9:dd:c25:c25:94de:ef40/1272c19:dd:d9:dd:c25:c25:94de:ef41
1622c19:dd:d9:dd:c25:c25:94de:ef42/1272c19:dd:d9:dd:c25:c25:94de:ef43
1632c19:dd:d9:dd:c25:c25:94de:ef44/1272c19:dd:d9:dd:c25:c25:94de:ef45
1642c19:dd:d9:dd:c25:c25:94de:ef46/1272c19:dd:d9:dd:c25:c25:94de:ef47
1652c19:dd:d9:dd:c25:c25:94de:ef48/1272c19:dd:d9:dd:c25:c25:94de:ef49
1662c19:dd:d9:dd:c25:c25:94de:ef4a/1272c19:dd:d9:dd:c25:c25:94de:ef4b
1672c19:dd:d9:dd:c25:c25:94de:ef4c/1272c19:dd:d9:dd:c25:c25:94de:ef4d
1682c19:dd:d9:dd:c25:c25:94de:ef4e/1272c19:dd:d9:dd:c25:c25:94de:ef4f
1692c19:dd:d9:dd:c25:c25:94de:ef50/1272c19:dd:d9:dd:c25:c25:94de:ef51
1702c19:dd:d9:dd:c25:c25:94de:ef52/1272c19:dd:d9:dd:c25:c25:94de:ef53
1712c19:dd:d9:dd:c25:c25:94de:ef54/1272c19:dd:d9:dd:c25:c25:94de:ef55
1722c19:dd:d9:dd:c25:c25:94de:ef56/1272c19:dd:d9:dd:c25:c25:94de:ef57
1732c19:dd:d9:dd:c25:c25:94de:ef58/1272c19:dd:d9:dd:c25:c25:94de:ef59
1742c19:dd:d9:dd:c25:c25:94de:ef5a/1272c19:dd:d9:dd:c25:c25:94de:ef5b
1752c19:dd:d9:dd:c25:c25:94de:ef5c/1272c19:dd:d9:dd:c25:c25:94de:ef5d
1762c19:dd:d9:dd:c25:c25:94de:ef5e/1272c19:dd:d9:dd:c25:c25:94de:ef5f
1772c19:dd:d9:dd:c25:c25:94de:ef60/1272c19:dd:d9:dd:c25:c25:94de:ef61
1782c19:dd:d9:dd:c25:c25:94de:ef62/1272c19:dd:d9:dd:c25:c25:94de:ef63
1792c19:dd:d9:dd:c25:c25:94de:ef64/1272c19:dd:d9:dd:c25:c25:94de:ef65
1802c19:dd:d9:dd:c25:c25:94de:ef66/1272c19:dd:d9:dd:c25:c25:94de:ef67
1812c19:dd:d9:dd:c25:c25:94de:ef68/1272c19:dd:d9:dd:c25:c25:94de:ef69
1822c19:dd:d9:dd:c25:c25:94de:ef6a/1272c19:dd:d9:dd:c25:c25:94de:ef6b
1832c19:dd:d9:dd:c25:c25:94de:ef6c/1272c19:dd:d9:dd:c25:c25:94de:ef6d
1842c19:dd:d9:dd:c25:c25:94de:ef6e/1272c19:dd:d9:dd:c25:c25:94de:ef6f
1852c19:dd:d9:dd:c25:c25:94de:ef70/1272c19:dd:d9:dd:c25:c25:94de:ef71
1862c19:dd:d9:dd:c25:c25:94de:ef72/1272c19:dd:d9:dd:c25:c25:94de:ef73
1872c19:dd:d9:dd:c25:c25:94de:ef74/1272c19:dd:d9:dd:c25:c25:94de:ef75
1882c19:dd:d9:dd:c25:c25:94de:ef76/1272c19:dd:d9:dd:c25:c25:94de:ef77
1892c19:dd:d9:dd:c25:c25:94de:ef78/1272c19:dd:d9:dd:c25:c25:94de:ef79
1902c19:dd:d9:dd:c25:c25:94de:ef7a/1272c19:dd:d9:dd:c25:c25:94de:ef7b
1912c19:dd:d9:dd:c25:c25:94de:ef7c/1272c19:dd:d9:dd:c25:c25:94de:ef7d
1922c19:dd:d9:dd:c25:c25:94de:ef7e/1272c19:dd:d9:dd:c25:c25:94de:ef7f
1932c19:dd:d9:dd:c25:c25:94de:ef80/1272c19:dd:d9:dd:c25:c25:94de:ef81
1942c19:dd:d9:dd:c25:c25:94de:ef82/1272c19:dd:d9:dd:c25:c25:94de:ef83
1952c19:dd:d9:dd:c25:c25:94de:ef84/1272c19:dd:d9:dd:c25:c25:94de:ef85
1962c19:dd:d9:dd:c25:c25:94de:ef86/1272c19:dd:d9:dd:c25:c25:94de:ef87
1972c19:dd:d9:dd:c25:c25:94de:ef88/1272c19:dd:d9:dd:c25:c25:94de:ef89
1982c19:dd:d9:dd:c25:c25:94de:ef8a/1272c19:dd:d9:dd:c25:c25:94de:ef8b
1992c19:dd:d9:dd:c25:c25:94de:ef8c/1272c19:dd:d9:dd:c25:c25:94de:ef8d
2002c19:dd:d9:dd:c25:c25:94de:ef8e/1272c19:dd:d9:dd:c25:c25:94de:ef8f
2012c19:dd:d9:dd:c25:c25:94de:ef90/1272c19:dd:d9:dd:c25:c25:94de:ef91
2022c19:dd:d9:dd:c25:c25:94de:ef92/1272c19:dd:d9:dd:c25:c25:94de:ef93
2032c19:dd:d9:dd:c25:c25:94de:ef94/1272c19:dd:d9:dd:c25:c25:94de:ef95
2042c19:dd:d9:dd:c25:c25:94de:ef96/1272c19:dd:d9:dd:c25:c25:94de:ef97
2052c19:dd:d9:dd:c25:c25:94de:ef98/1272c19:dd:d9:dd:c25:c25:94de:ef99
2062c19:dd:d9:dd:c25:c25:94de:ef9a/1272c19:dd:d9:dd:c25:c25:94de:ef9b
2072c19:dd:d9:dd:c25:c25:94de:ef9c/1272c19:dd:d9:dd:c25:c25:94de:ef9d
2082c19:dd:d9:dd:c25:c25:94de:ef9e/1272c19:dd:d9:dd:c25:c25:94de:ef9f
2092c19:dd:d9:dd:c25:c25:94de:efa0/1272c19:dd:d9:dd:c25:c25:94de:efa1
2102c19:dd:d9:dd:c25:c25:94de:efa2/1272c19:dd:d9:dd:c25:c25:94de:efa3
2112c19:dd:d9:dd:c25:c25:94de:efa4/1272c19:dd:d9:dd:c25:c25:94de:efa5
2122c19:dd:d9:dd:c25:c25:94de:efa6/1272c19:dd:d9:dd:c25:c25:94de:efa7
2132c19:dd:d9:dd:c25:c25:94de:efa8/1272c19:dd:d9:dd:c25:c25:94de:efa9
2142c19:dd:d9:dd:c25:c25:94de:efaa/1272c19:dd:d9:dd:c25:c25:94de:efab
2152c19:dd:d9:dd:c25:c25:94de:efac/1272c19:dd:d9:dd:c25:c25:94de:efad
2162c19:dd:d9:dd:c25:c25:94de:efae/1272c19:dd:d9:dd:c25:c25:94de:efaf
2172c19:dd:d9:dd:c25:c25:94de:efb0/1272c19:dd:d9:dd:c25:c25:94de:efb1
2182c19:dd:d9:dd:c25:c25:94de:efb2/1272c19:dd:d9:dd:c25:c25:94de:efb3
2192c19:dd:d9:dd:c25:c25:94de:efb4/1272c19:dd:d9:dd:c25:c25:94de:efb5
2202c19:dd:d9:dd:c25:c25:94de:efb6/1272c19:dd:d9:dd:c25:c25:94de:efb7
2212c19:dd:d9:dd:c25:c25:94de:efb8/1272c19:dd:d9:dd:c25:c25:94de:efb9
2222c19:dd:d9:dd:c25:c25:94de:efba/1272c19:dd:d9:dd:c25:c25:94de:efbb
2232c19:dd:d9:dd:c25:c25:94de:efbc/1272c19:dd:d9:dd:c25:c25:94de:efbd
2242c19:dd:d9:dd:c25:c25:94de:efbe/1272c19:dd:d9:dd:c25:c25:94de:efbf
2252c19:dd:d9:dd:c25:c25:94de:efc0/1272c19:dd:d9:dd:c25:c25:94de:efc1
2262c19:dd:d9:dd:c25:c25:94de:efc2/1272c19:dd:d9:dd:c25:c25:94de:efc3
2272c19:dd:d9:dd:c25:c25:94de:efc4/1272c19:dd:d9:dd:c25:c25:94de:efc5
2282c19:dd:d9:dd:c25:c25:94de:efc6/1272c19:dd:d9:dd:c25:c25:94de:efc7
2292c19:dd:d9:dd:c25:c25:94de:efc8/1272c19:dd:d9:dd:c25:c25:94de:efc9
2302c19:dd:d9:dd:c25:c25:94de:efca/1272c19:dd:d9:dd:c25:c25:94de:efcb
2312c19:dd:d9:dd:c25:c25:94de:efcc/1272c19:dd:d9:dd:c25:c25:94de:efcd
2322c19:dd:d9:dd:c25:c25:94de:efce/1272c19:dd:d9:dd:c25:c25:94de:efcf
2332c19:dd:d9:dd:c25:c25:94de:efd0/1272c19:dd:d9:dd:c25:c25:94de:efd1
2342c19:dd:d9:dd:c25:c25:94de:efd2/1272c19:dd:d9:dd:c25:c25:94de:efd3
2352c19:dd:d9:dd:c25:c25:94de:efd4/1272c19:dd:d9:dd:c25:c25:94de:efd5
2362c19:dd:d9:dd:c25:c25:94de:efd6/1272c19:dd:d9:dd:c25:c25:94de:efd7
2372c19:dd:d9:dd:c25:c25:94de:efd8/1272c19:dd:d9:dd:c25:c25:94de:efd9
2382c19:dd:d9:dd:c25:c25:94de:efda/1272c19:dd:d9:dd:c25:c25:94de:efdb
2392c19:dd:d9:dd:c25:c25:94de:efdc/1272c19:dd:d9:dd:c25:c25:94de:efdd
2402c19:dd:d9:dd:c25:c25:94de:efde/1272c19:dd:d9:dd:c25:c25:94de:efdf
2412c19:dd:d9:dd:c25:c25:94de:efe0/1272c19:dd:d9:dd:c25:c25:94de:efe1
2422c19:dd:d9:dd:c25:c25:94de:efe2/1272c19:dd:d9:dd:c25:c25:94de:efe3
2432c19:dd:d9:dd:c25:c25:94de:efe4/1272c19:dd:d9:dd:c25:c25:94de:efe5
2442c19:dd:d9:dd:c25:c25:94de:efe6/1272c19:dd:d9:dd:c25:c25:94de:efe7
2452c19:dd:d9:dd:c25:c25:94de:efe8/1272c19:dd:d9:dd:c25:c25:94de:efe9
2462c19:dd:d9:dd:c25:c25:94de:efea/1272c19:dd:d9:dd:c25:c25:94de:efeb
2472c19:dd:d9:dd:c25:c25:94de:efec/1272c19:dd:d9:dd:c25:c25:94de:efed
2482c19:dd:d9:dd:c25:c25:94de:efee/1272c19:dd:d9:dd:c25:c25:94de:efef
2492c19:dd:d9:dd:c25:c25:94de:eff0/1272c19:dd:d9:dd:c25:c25:94de:eff1
2502c19:dd:d9:dd:c25:c25:94de:eff2/1272c19:dd:d9:dd:c25:c25:94de:eff3
2512c19:dd:d9:dd:c25:c25:94de:eff4/1272c19:dd:d9:dd:c25:c25:94de:eff5
2522c19:dd:d9:dd:c25:c25:94de:eff6/1272c19:dd:d9:dd:c25:c25:94de:eff7
2532c19:dd:d9:dd:c25:c25:94de:eff8/1272c19:dd:d9:dd:c25:c25:94de:eff9
2542c19:dd:d9:dd:c25:c25:94de:effa/1272c19:dd:d9:dd:c25:c25:94de:effb
2552c19:dd:d9:dd:c25:c25:94de:effc/1272c19:dd:d9:dd:c25:c25:94de:effd
2562c19:dd:d9:dd:c25:c25:94de:effe/1272c19:dd:d9:dd:c25:c25:94de:efff

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.