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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:ae00/119
First address
2c19:dd:d9:dd:c25:c25:94de:ae00
Last address
2c19:dd:d9:dd:c25:c25:94de:afff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:ae00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
e.a.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.a.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:ae00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:ae00/1272c19:dd:d9:dd:c25:c25:94de:ae01
22c19:dd:d9:dd:c25:c25:94de:ae02/1272c19:dd:d9:dd:c25:c25:94de:ae03
32c19:dd:d9:dd:c25:c25:94de:ae04/1272c19:dd:d9:dd:c25:c25:94de:ae05
42c19:dd:d9:dd:c25:c25:94de:ae06/1272c19:dd:d9:dd:c25:c25:94de:ae07
52c19:dd:d9:dd:c25:c25:94de:ae08/1272c19:dd:d9:dd:c25:c25:94de:ae09
62c19:dd:d9:dd:c25:c25:94de:ae0a/1272c19:dd:d9:dd:c25:c25:94de:ae0b
72c19:dd:d9:dd:c25:c25:94de:ae0c/1272c19:dd:d9:dd:c25:c25:94de:ae0d
82c19:dd:d9:dd:c25:c25:94de:ae0e/1272c19:dd:d9:dd:c25:c25:94de:ae0f
92c19:dd:d9:dd:c25:c25:94de:ae10/1272c19:dd:d9:dd:c25:c25:94de:ae11
102c19:dd:d9:dd:c25:c25:94de:ae12/1272c19:dd:d9:dd:c25:c25:94de:ae13
112c19:dd:d9:dd:c25:c25:94de:ae14/1272c19:dd:d9:dd:c25:c25:94de:ae15
122c19:dd:d9:dd:c25:c25:94de:ae16/1272c19:dd:d9:dd:c25:c25:94de:ae17
132c19:dd:d9:dd:c25:c25:94de:ae18/1272c19:dd:d9:dd:c25:c25:94de:ae19
142c19:dd:d9:dd:c25:c25:94de:ae1a/1272c19:dd:d9:dd:c25:c25:94de:ae1b
152c19:dd:d9:dd:c25:c25:94de:ae1c/1272c19:dd:d9:dd:c25:c25:94de:ae1d
162c19:dd:d9:dd:c25:c25:94de:ae1e/1272c19:dd:d9:dd:c25:c25:94de:ae1f
172c19:dd:d9:dd:c25:c25:94de:ae20/1272c19:dd:d9:dd:c25:c25:94de:ae21
182c19:dd:d9:dd:c25:c25:94de:ae22/1272c19:dd:d9:dd:c25:c25:94de:ae23
192c19:dd:d9:dd:c25:c25:94de:ae24/1272c19:dd:d9:dd:c25:c25:94de:ae25
202c19:dd:d9:dd:c25:c25:94de:ae26/1272c19:dd:d9:dd:c25:c25:94de:ae27
212c19:dd:d9:dd:c25:c25:94de:ae28/1272c19:dd:d9:dd:c25:c25:94de:ae29
222c19:dd:d9:dd:c25:c25:94de:ae2a/1272c19:dd:d9:dd:c25:c25:94de:ae2b
232c19:dd:d9:dd:c25:c25:94de:ae2c/1272c19:dd:d9:dd:c25:c25:94de:ae2d
242c19:dd:d9:dd:c25:c25:94de:ae2e/1272c19:dd:d9:dd:c25:c25:94de:ae2f
252c19:dd:d9:dd:c25:c25:94de:ae30/1272c19:dd:d9:dd:c25:c25:94de:ae31
262c19:dd:d9:dd:c25:c25:94de:ae32/1272c19:dd:d9:dd:c25:c25:94de:ae33
272c19:dd:d9:dd:c25:c25:94de:ae34/1272c19:dd:d9:dd:c25:c25:94de:ae35
282c19:dd:d9:dd:c25:c25:94de:ae36/1272c19:dd:d9:dd:c25:c25:94de:ae37
292c19:dd:d9:dd:c25:c25:94de:ae38/1272c19:dd:d9:dd:c25:c25:94de:ae39
302c19:dd:d9:dd:c25:c25:94de:ae3a/1272c19:dd:d9:dd:c25:c25:94de:ae3b
312c19:dd:d9:dd:c25:c25:94de:ae3c/1272c19:dd:d9:dd:c25:c25:94de:ae3d
322c19:dd:d9:dd:c25:c25:94de:ae3e/1272c19:dd:d9:dd:c25:c25:94de:ae3f
332c19:dd:d9:dd:c25:c25:94de:ae40/1272c19:dd:d9:dd:c25:c25:94de:ae41
342c19:dd:d9:dd:c25:c25:94de:ae42/1272c19:dd:d9:dd:c25:c25:94de:ae43
352c19:dd:d9:dd:c25:c25:94de:ae44/1272c19:dd:d9:dd:c25:c25:94de:ae45
362c19:dd:d9:dd:c25:c25:94de:ae46/1272c19:dd:d9:dd:c25:c25:94de:ae47
372c19:dd:d9:dd:c25:c25:94de:ae48/1272c19:dd:d9:dd:c25:c25:94de:ae49
382c19:dd:d9:dd:c25:c25:94de:ae4a/1272c19:dd:d9:dd:c25:c25:94de:ae4b
392c19:dd:d9:dd:c25:c25:94de:ae4c/1272c19:dd:d9:dd:c25:c25:94de:ae4d
402c19:dd:d9:dd:c25:c25:94de:ae4e/1272c19:dd:d9:dd:c25:c25:94de:ae4f
412c19:dd:d9:dd:c25:c25:94de:ae50/1272c19:dd:d9:dd:c25:c25:94de:ae51
422c19:dd:d9:dd:c25:c25:94de:ae52/1272c19:dd:d9:dd:c25:c25:94de:ae53
432c19:dd:d9:dd:c25:c25:94de:ae54/1272c19:dd:d9:dd:c25:c25:94de:ae55
442c19:dd:d9:dd:c25:c25:94de:ae56/1272c19:dd:d9:dd:c25:c25:94de:ae57
452c19:dd:d9:dd:c25:c25:94de:ae58/1272c19:dd:d9:dd:c25:c25:94de:ae59
462c19:dd:d9:dd:c25:c25:94de:ae5a/1272c19:dd:d9:dd:c25:c25:94de:ae5b
472c19:dd:d9:dd:c25:c25:94de:ae5c/1272c19:dd:d9:dd:c25:c25:94de:ae5d
482c19:dd:d9:dd:c25:c25:94de:ae5e/1272c19:dd:d9:dd:c25:c25:94de:ae5f
492c19:dd:d9:dd:c25:c25:94de:ae60/1272c19:dd:d9:dd:c25:c25:94de:ae61
502c19:dd:d9:dd:c25:c25:94de:ae62/1272c19:dd:d9:dd:c25:c25:94de:ae63
512c19:dd:d9:dd:c25:c25:94de:ae64/1272c19:dd:d9:dd:c25:c25:94de:ae65
522c19:dd:d9:dd:c25:c25:94de:ae66/1272c19:dd:d9:dd:c25:c25:94de:ae67
532c19:dd:d9:dd:c25:c25:94de:ae68/1272c19:dd:d9:dd:c25:c25:94de:ae69
542c19:dd:d9:dd:c25:c25:94de:ae6a/1272c19:dd:d9:dd:c25:c25:94de:ae6b
552c19:dd:d9:dd:c25:c25:94de:ae6c/1272c19:dd:d9:dd:c25:c25:94de:ae6d
562c19:dd:d9:dd:c25:c25:94de:ae6e/1272c19:dd:d9:dd:c25:c25:94de:ae6f
572c19:dd:d9:dd:c25:c25:94de:ae70/1272c19:dd:d9:dd:c25:c25:94de:ae71
582c19:dd:d9:dd:c25:c25:94de:ae72/1272c19:dd:d9:dd:c25:c25:94de:ae73
592c19:dd:d9:dd:c25:c25:94de:ae74/1272c19:dd:d9:dd:c25:c25:94de:ae75
602c19:dd:d9:dd:c25:c25:94de:ae76/1272c19:dd:d9:dd:c25:c25:94de:ae77
612c19:dd:d9:dd:c25:c25:94de:ae78/1272c19:dd:d9:dd:c25:c25:94de:ae79
622c19:dd:d9:dd:c25:c25:94de:ae7a/1272c19:dd:d9:dd:c25:c25:94de:ae7b
632c19:dd:d9:dd:c25:c25:94de:ae7c/1272c19:dd:d9:dd:c25:c25:94de:ae7d
642c19:dd:d9:dd:c25:c25:94de:ae7e/1272c19:dd:d9:dd:c25:c25:94de:ae7f
652c19:dd:d9:dd:c25:c25:94de:ae80/1272c19:dd:d9:dd:c25:c25:94de:ae81
662c19:dd:d9:dd:c25:c25:94de:ae82/1272c19:dd:d9:dd:c25:c25:94de:ae83
672c19:dd:d9:dd:c25:c25:94de:ae84/1272c19:dd:d9:dd:c25:c25:94de:ae85
682c19:dd:d9:dd:c25:c25:94de:ae86/1272c19:dd:d9:dd:c25:c25:94de:ae87
692c19:dd:d9:dd:c25:c25:94de:ae88/1272c19:dd:d9:dd:c25:c25:94de:ae89
702c19:dd:d9:dd:c25:c25:94de:ae8a/1272c19:dd:d9:dd:c25:c25:94de:ae8b
712c19:dd:d9:dd:c25:c25:94de:ae8c/1272c19:dd:d9:dd:c25:c25:94de:ae8d
722c19:dd:d9:dd:c25:c25:94de:ae8e/1272c19:dd:d9:dd:c25:c25:94de:ae8f
732c19:dd:d9:dd:c25:c25:94de:ae90/1272c19:dd:d9:dd:c25:c25:94de:ae91
742c19:dd:d9:dd:c25:c25:94de:ae92/1272c19:dd:d9:dd:c25:c25:94de:ae93
752c19:dd:d9:dd:c25:c25:94de:ae94/1272c19:dd:d9:dd:c25:c25:94de:ae95
762c19:dd:d9:dd:c25:c25:94de:ae96/1272c19:dd:d9:dd:c25:c25:94de:ae97
772c19:dd:d9:dd:c25:c25:94de:ae98/1272c19:dd:d9:dd:c25:c25:94de:ae99
782c19:dd:d9:dd:c25:c25:94de:ae9a/1272c19:dd:d9:dd:c25:c25:94de:ae9b
792c19:dd:d9:dd:c25:c25:94de:ae9c/1272c19:dd:d9:dd:c25:c25:94de:ae9d
802c19:dd:d9:dd:c25:c25:94de:ae9e/1272c19:dd:d9:dd:c25:c25:94de:ae9f
812c19:dd:d9:dd:c25:c25:94de:aea0/1272c19:dd:d9:dd:c25:c25:94de:aea1
822c19:dd:d9:dd:c25:c25:94de:aea2/1272c19:dd:d9:dd:c25:c25:94de:aea3
832c19:dd:d9:dd:c25:c25:94de:aea4/1272c19:dd:d9:dd:c25:c25:94de:aea5
842c19:dd:d9:dd:c25:c25:94de:aea6/1272c19:dd:d9:dd:c25:c25:94de:aea7
852c19:dd:d9:dd:c25:c25:94de:aea8/1272c19:dd:d9:dd:c25:c25:94de:aea9
862c19:dd:d9:dd:c25:c25:94de:aeaa/1272c19:dd:d9:dd:c25:c25:94de:aeab
872c19:dd:d9:dd:c25:c25:94de:aeac/1272c19:dd:d9:dd:c25:c25:94de:aead
882c19:dd:d9:dd:c25:c25:94de:aeae/1272c19:dd:d9:dd:c25:c25:94de:aeaf
892c19:dd:d9:dd:c25:c25:94de:aeb0/1272c19:dd:d9:dd:c25:c25:94de:aeb1
902c19:dd:d9:dd:c25:c25:94de:aeb2/1272c19:dd:d9:dd:c25:c25:94de:aeb3
912c19:dd:d9:dd:c25:c25:94de:aeb4/1272c19:dd:d9:dd:c25:c25:94de:aeb5
922c19:dd:d9:dd:c25:c25:94de:aeb6/1272c19:dd:d9:dd:c25:c25:94de:aeb7
932c19:dd:d9:dd:c25:c25:94de:aeb8/1272c19:dd:d9:dd:c25:c25:94de:aeb9
942c19:dd:d9:dd:c25:c25:94de:aeba/1272c19:dd:d9:dd:c25:c25:94de:aebb
952c19:dd:d9:dd:c25:c25:94de:aebc/1272c19:dd:d9:dd:c25:c25:94de:aebd
962c19:dd:d9:dd:c25:c25:94de:aebe/1272c19:dd:d9:dd:c25:c25:94de:aebf
972c19:dd:d9:dd:c25:c25:94de:aec0/1272c19:dd:d9:dd:c25:c25:94de:aec1
982c19:dd:d9:dd:c25:c25:94de:aec2/1272c19:dd:d9:dd:c25:c25:94de:aec3
992c19:dd:d9:dd:c25:c25:94de:aec4/1272c19:dd:d9:dd:c25:c25:94de:aec5
1002c19:dd:d9:dd:c25:c25:94de:aec6/1272c19:dd:d9:dd:c25:c25:94de:aec7
1012c19:dd:d9:dd:c25:c25:94de:aec8/1272c19:dd:d9:dd:c25:c25:94de:aec9
1022c19:dd:d9:dd:c25:c25:94de:aeca/1272c19:dd:d9:dd:c25:c25:94de:aecb
1032c19:dd:d9:dd:c25:c25:94de:aecc/1272c19:dd:d9:dd:c25:c25:94de:aecd
1042c19:dd:d9:dd:c25:c25:94de:aece/1272c19:dd:d9:dd:c25:c25:94de:aecf
1052c19:dd:d9:dd:c25:c25:94de:aed0/1272c19:dd:d9:dd:c25:c25:94de:aed1
1062c19:dd:d9:dd:c25:c25:94de:aed2/1272c19:dd:d9:dd:c25:c25:94de:aed3
1072c19:dd:d9:dd:c25:c25:94de:aed4/1272c19:dd:d9:dd:c25:c25:94de:aed5
1082c19:dd:d9:dd:c25:c25:94de:aed6/1272c19:dd:d9:dd:c25:c25:94de:aed7
1092c19:dd:d9:dd:c25:c25:94de:aed8/1272c19:dd:d9:dd:c25:c25:94de:aed9
1102c19:dd:d9:dd:c25:c25:94de:aeda/1272c19:dd:d9:dd:c25:c25:94de:aedb
1112c19:dd:d9:dd:c25:c25:94de:aedc/1272c19:dd:d9:dd:c25:c25:94de:aedd
1122c19:dd:d9:dd:c25:c25:94de:aede/1272c19:dd:d9:dd:c25:c25:94de:aedf
1132c19:dd:d9:dd:c25:c25:94de:aee0/1272c19:dd:d9:dd:c25:c25:94de:aee1
1142c19:dd:d9:dd:c25:c25:94de:aee2/1272c19:dd:d9:dd:c25:c25:94de:aee3
1152c19:dd:d9:dd:c25:c25:94de:aee4/1272c19:dd:d9:dd:c25:c25:94de:aee5
1162c19:dd:d9:dd:c25:c25:94de:aee6/1272c19:dd:d9:dd:c25:c25:94de:aee7
1172c19:dd:d9:dd:c25:c25:94de:aee8/1272c19:dd:d9:dd:c25:c25:94de:aee9
1182c19:dd:d9:dd:c25:c25:94de:aeea/1272c19:dd:d9:dd:c25:c25:94de:aeeb
1192c19:dd:d9:dd:c25:c25:94de:aeec/1272c19:dd:d9:dd:c25:c25:94de:aeed
1202c19:dd:d9:dd:c25:c25:94de:aeee/1272c19:dd:d9:dd:c25:c25:94de:aeef
1212c19:dd:d9:dd:c25:c25:94de:aef0/1272c19:dd:d9:dd:c25:c25:94de:aef1
1222c19:dd:d9:dd:c25:c25:94de:aef2/1272c19:dd:d9:dd:c25:c25:94de:aef3
1232c19:dd:d9:dd:c25:c25:94de:aef4/1272c19:dd:d9:dd:c25:c25:94de:aef5
1242c19:dd:d9:dd:c25:c25:94de:aef6/1272c19:dd:d9:dd:c25:c25:94de:aef7
1252c19:dd:d9:dd:c25:c25:94de:aef8/1272c19:dd:d9:dd:c25:c25:94de:aef9
1262c19:dd:d9:dd:c25:c25:94de:aefa/1272c19:dd:d9:dd:c25:c25:94de:aefb
1272c19:dd:d9:dd:c25:c25:94de:aefc/1272c19:dd:d9:dd:c25:c25:94de:aefd
1282c19:dd:d9:dd:c25:c25:94de:aefe/1272c19:dd:d9:dd:c25:c25:94de:aeff
1292c19:dd:d9:dd:c25:c25:94de:af00/1272c19:dd:d9:dd:c25:c25:94de:af01
1302c19:dd:d9:dd:c25:c25:94de:af02/1272c19:dd:d9:dd:c25:c25:94de:af03
1312c19:dd:d9:dd:c25:c25:94de:af04/1272c19:dd:d9:dd:c25:c25:94de:af05
1322c19:dd:d9:dd:c25:c25:94de:af06/1272c19:dd:d9:dd:c25:c25:94de:af07
1332c19:dd:d9:dd:c25:c25:94de:af08/1272c19:dd:d9:dd:c25:c25:94de:af09
1342c19:dd:d9:dd:c25:c25:94de:af0a/1272c19:dd:d9:dd:c25:c25:94de:af0b
1352c19:dd:d9:dd:c25:c25:94de:af0c/1272c19:dd:d9:dd:c25:c25:94de:af0d
1362c19:dd:d9:dd:c25:c25:94de:af0e/1272c19:dd:d9:dd:c25:c25:94de:af0f
1372c19:dd:d9:dd:c25:c25:94de:af10/1272c19:dd:d9:dd:c25:c25:94de:af11
1382c19:dd:d9:dd:c25:c25:94de:af12/1272c19:dd:d9:dd:c25:c25:94de:af13
1392c19:dd:d9:dd:c25:c25:94de:af14/1272c19:dd:d9:dd:c25:c25:94de:af15
1402c19:dd:d9:dd:c25:c25:94de:af16/1272c19:dd:d9:dd:c25:c25:94de:af17
1412c19:dd:d9:dd:c25:c25:94de:af18/1272c19:dd:d9:dd:c25:c25:94de:af19
1422c19:dd:d9:dd:c25:c25:94de:af1a/1272c19:dd:d9:dd:c25:c25:94de:af1b
1432c19:dd:d9:dd:c25:c25:94de:af1c/1272c19:dd:d9:dd:c25:c25:94de:af1d
1442c19:dd:d9:dd:c25:c25:94de:af1e/1272c19:dd:d9:dd:c25:c25:94de:af1f
1452c19:dd:d9:dd:c25:c25:94de:af20/1272c19:dd:d9:dd:c25:c25:94de:af21
1462c19:dd:d9:dd:c25:c25:94de:af22/1272c19:dd:d9:dd:c25:c25:94de:af23
1472c19:dd:d9:dd:c25:c25:94de:af24/1272c19:dd:d9:dd:c25:c25:94de:af25
1482c19:dd:d9:dd:c25:c25:94de:af26/1272c19:dd:d9:dd:c25:c25:94de:af27
1492c19:dd:d9:dd:c25:c25:94de:af28/1272c19:dd:d9:dd:c25:c25:94de:af29
1502c19:dd:d9:dd:c25:c25:94de:af2a/1272c19:dd:d9:dd:c25:c25:94de:af2b
1512c19:dd:d9:dd:c25:c25:94de:af2c/1272c19:dd:d9:dd:c25:c25:94de:af2d
1522c19:dd:d9:dd:c25:c25:94de:af2e/1272c19:dd:d9:dd:c25:c25:94de:af2f
1532c19:dd:d9:dd:c25:c25:94de:af30/1272c19:dd:d9:dd:c25:c25:94de:af31
1542c19:dd:d9:dd:c25:c25:94de:af32/1272c19:dd:d9:dd:c25:c25:94de:af33
1552c19:dd:d9:dd:c25:c25:94de:af34/1272c19:dd:d9:dd:c25:c25:94de:af35
1562c19:dd:d9:dd:c25:c25:94de:af36/1272c19:dd:d9:dd:c25:c25:94de:af37
1572c19:dd:d9:dd:c25:c25:94de:af38/1272c19:dd:d9:dd:c25:c25:94de:af39
1582c19:dd:d9:dd:c25:c25:94de:af3a/1272c19:dd:d9:dd:c25:c25:94de:af3b
1592c19:dd:d9:dd:c25:c25:94de:af3c/1272c19:dd:d9:dd:c25:c25:94de:af3d
1602c19:dd:d9:dd:c25:c25:94de:af3e/1272c19:dd:d9:dd:c25:c25:94de:af3f
1612c19:dd:d9:dd:c25:c25:94de:af40/1272c19:dd:d9:dd:c25:c25:94de:af41
1622c19:dd:d9:dd:c25:c25:94de:af42/1272c19:dd:d9:dd:c25:c25:94de:af43
1632c19:dd:d9:dd:c25:c25:94de:af44/1272c19:dd:d9:dd:c25:c25:94de:af45
1642c19:dd:d9:dd:c25:c25:94de:af46/1272c19:dd:d9:dd:c25:c25:94de:af47
1652c19:dd:d9:dd:c25:c25:94de:af48/1272c19:dd:d9:dd:c25:c25:94de:af49
1662c19:dd:d9:dd:c25:c25:94de:af4a/1272c19:dd:d9:dd:c25:c25:94de:af4b
1672c19:dd:d9:dd:c25:c25:94de:af4c/1272c19:dd:d9:dd:c25:c25:94de:af4d
1682c19:dd:d9:dd:c25:c25:94de:af4e/1272c19:dd:d9:dd:c25:c25:94de:af4f
1692c19:dd:d9:dd:c25:c25:94de:af50/1272c19:dd:d9:dd:c25:c25:94de:af51
1702c19:dd:d9:dd:c25:c25:94de:af52/1272c19:dd:d9:dd:c25:c25:94de:af53
1712c19:dd:d9:dd:c25:c25:94de:af54/1272c19:dd:d9:dd:c25:c25:94de:af55
1722c19:dd:d9:dd:c25:c25:94de:af56/1272c19:dd:d9:dd:c25:c25:94de:af57
1732c19:dd:d9:dd:c25:c25:94de:af58/1272c19:dd:d9:dd:c25:c25:94de:af59
1742c19:dd:d9:dd:c25:c25:94de:af5a/1272c19:dd:d9:dd:c25:c25:94de:af5b
1752c19:dd:d9:dd:c25:c25:94de:af5c/1272c19:dd:d9:dd:c25:c25:94de:af5d
1762c19:dd:d9:dd:c25:c25:94de:af5e/1272c19:dd:d9:dd:c25:c25:94de:af5f
1772c19:dd:d9:dd:c25:c25:94de:af60/1272c19:dd:d9:dd:c25:c25:94de:af61
1782c19:dd:d9:dd:c25:c25:94de:af62/1272c19:dd:d9:dd:c25:c25:94de:af63
1792c19:dd:d9:dd:c25:c25:94de:af64/1272c19:dd:d9:dd:c25:c25:94de:af65
1802c19:dd:d9:dd:c25:c25:94de:af66/1272c19:dd:d9:dd:c25:c25:94de:af67
1812c19:dd:d9:dd:c25:c25:94de:af68/1272c19:dd:d9:dd:c25:c25:94de:af69
1822c19:dd:d9:dd:c25:c25:94de:af6a/1272c19:dd:d9:dd:c25:c25:94de:af6b
1832c19:dd:d9:dd:c25:c25:94de:af6c/1272c19:dd:d9:dd:c25:c25:94de:af6d
1842c19:dd:d9:dd:c25:c25:94de:af6e/1272c19:dd:d9:dd:c25:c25:94de:af6f
1852c19:dd:d9:dd:c25:c25:94de:af70/1272c19:dd:d9:dd:c25:c25:94de:af71
1862c19:dd:d9:dd:c25:c25:94de:af72/1272c19:dd:d9:dd:c25:c25:94de:af73
1872c19:dd:d9:dd:c25:c25:94de:af74/1272c19:dd:d9:dd:c25:c25:94de:af75
1882c19:dd:d9:dd:c25:c25:94de:af76/1272c19:dd:d9:dd:c25:c25:94de:af77
1892c19:dd:d9:dd:c25:c25:94de:af78/1272c19:dd:d9:dd:c25:c25:94de:af79
1902c19:dd:d9:dd:c25:c25:94de:af7a/1272c19:dd:d9:dd:c25:c25:94de:af7b
1912c19:dd:d9:dd:c25:c25:94de:af7c/1272c19:dd:d9:dd:c25:c25:94de:af7d
1922c19:dd:d9:dd:c25:c25:94de:af7e/1272c19:dd:d9:dd:c25:c25:94de:af7f
1932c19:dd:d9:dd:c25:c25:94de:af80/1272c19:dd:d9:dd:c25:c25:94de:af81
1942c19:dd:d9:dd:c25:c25:94de:af82/1272c19:dd:d9:dd:c25:c25:94de:af83
1952c19:dd:d9:dd:c25:c25:94de:af84/1272c19:dd:d9:dd:c25:c25:94de:af85
1962c19:dd:d9:dd:c25:c25:94de:af86/1272c19:dd:d9:dd:c25:c25:94de:af87
1972c19:dd:d9:dd:c25:c25:94de:af88/1272c19:dd:d9:dd:c25:c25:94de:af89
1982c19:dd:d9:dd:c25:c25:94de:af8a/1272c19:dd:d9:dd:c25:c25:94de:af8b
1992c19:dd:d9:dd:c25:c25:94de:af8c/1272c19:dd:d9:dd:c25:c25:94de:af8d
2002c19:dd:d9:dd:c25:c25:94de:af8e/1272c19:dd:d9:dd:c25:c25:94de:af8f
2012c19:dd:d9:dd:c25:c25:94de:af90/1272c19:dd:d9:dd:c25:c25:94de:af91
2022c19:dd:d9:dd:c25:c25:94de:af92/1272c19:dd:d9:dd:c25:c25:94de:af93
2032c19:dd:d9:dd:c25:c25:94de:af94/1272c19:dd:d9:dd:c25:c25:94de:af95
2042c19:dd:d9:dd:c25:c25:94de:af96/1272c19:dd:d9:dd:c25:c25:94de:af97
2052c19:dd:d9:dd:c25:c25:94de:af98/1272c19:dd:d9:dd:c25:c25:94de:af99
2062c19:dd:d9:dd:c25:c25:94de:af9a/1272c19:dd:d9:dd:c25:c25:94de:af9b
2072c19:dd:d9:dd:c25:c25:94de:af9c/1272c19:dd:d9:dd:c25:c25:94de:af9d
2082c19:dd:d9:dd:c25:c25:94de:af9e/1272c19:dd:d9:dd:c25:c25:94de:af9f
2092c19:dd:d9:dd:c25:c25:94de:afa0/1272c19:dd:d9:dd:c25:c25:94de:afa1
2102c19:dd:d9:dd:c25:c25:94de:afa2/1272c19:dd:d9:dd:c25:c25:94de:afa3
2112c19:dd:d9:dd:c25:c25:94de:afa4/1272c19:dd:d9:dd:c25:c25:94de:afa5
2122c19:dd:d9:dd:c25:c25:94de:afa6/1272c19:dd:d9:dd:c25:c25:94de:afa7
2132c19:dd:d9:dd:c25:c25:94de:afa8/1272c19:dd:d9:dd:c25:c25:94de:afa9
2142c19:dd:d9:dd:c25:c25:94de:afaa/1272c19:dd:d9:dd:c25:c25:94de:afab
2152c19:dd:d9:dd:c25:c25:94de:afac/1272c19:dd:d9:dd:c25:c25:94de:afad
2162c19:dd:d9:dd:c25:c25:94de:afae/1272c19:dd:d9:dd:c25:c25:94de:afaf
2172c19:dd:d9:dd:c25:c25:94de:afb0/1272c19:dd:d9:dd:c25:c25:94de:afb1
2182c19:dd:d9:dd:c25:c25:94de:afb2/1272c19:dd:d9:dd:c25:c25:94de:afb3
2192c19:dd:d9:dd:c25:c25:94de:afb4/1272c19:dd:d9:dd:c25:c25:94de:afb5
2202c19:dd:d9:dd:c25:c25:94de:afb6/1272c19:dd:d9:dd:c25:c25:94de:afb7
2212c19:dd:d9:dd:c25:c25:94de:afb8/1272c19:dd:d9:dd:c25:c25:94de:afb9
2222c19:dd:d9:dd:c25:c25:94de:afba/1272c19:dd:d9:dd:c25:c25:94de:afbb
2232c19:dd:d9:dd:c25:c25:94de:afbc/1272c19:dd:d9:dd:c25:c25:94de:afbd
2242c19:dd:d9:dd:c25:c25:94de:afbe/1272c19:dd:d9:dd:c25:c25:94de:afbf
2252c19:dd:d9:dd:c25:c25:94de:afc0/1272c19:dd:d9:dd:c25:c25:94de:afc1
2262c19:dd:d9:dd:c25:c25:94de:afc2/1272c19:dd:d9:dd:c25:c25:94de:afc3
2272c19:dd:d9:dd:c25:c25:94de:afc4/1272c19:dd:d9:dd:c25:c25:94de:afc5
2282c19:dd:d9:dd:c25:c25:94de:afc6/1272c19:dd:d9:dd:c25:c25:94de:afc7
2292c19:dd:d9:dd:c25:c25:94de:afc8/1272c19:dd:d9:dd:c25:c25:94de:afc9
2302c19:dd:d9:dd:c25:c25:94de:afca/1272c19:dd:d9:dd:c25:c25:94de:afcb
2312c19:dd:d9:dd:c25:c25:94de:afcc/1272c19:dd:d9:dd:c25:c25:94de:afcd
2322c19:dd:d9:dd:c25:c25:94de:afce/1272c19:dd:d9:dd:c25:c25:94de:afcf
2332c19:dd:d9:dd:c25:c25:94de:afd0/1272c19:dd:d9:dd:c25:c25:94de:afd1
2342c19:dd:d9:dd:c25:c25:94de:afd2/1272c19:dd:d9:dd:c25:c25:94de:afd3
2352c19:dd:d9:dd:c25:c25:94de:afd4/1272c19:dd:d9:dd:c25:c25:94de:afd5
2362c19:dd:d9:dd:c25:c25:94de:afd6/1272c19:dd:d9:dd:c25:c25:94de:afd7
2372c19:dd:d9:dd:c25:c25:94de:afd8/1272c19:dd:d9:dd:c25:c25:94de:afd9
2382c19:dd:d9:dd:c25:c25:94de:afda/1272c19:dd:d9:dd:c25:c25:94de:afdb
2392c19:dd:d9:dd:c25:c25:94de:afdc/1272c19:dd:d9:dd:c25:c25:94de:afdd
2402c19:dd:d9:dd:c25:c25:94de:afde/1272c19:dd:d9:dd:c25:c25:94de:afdf
2412c19:dd:d9:dd:c25:c25:94de:afe0/1272c19:dd:d9:dd:c25:c25:94de:afe1
2422c19:dd:d9:dd:c25:c25:94de:afe2/1272c19:dd:d9:dd:c25:c25:94de:afe3
2432c19:dd:d9:dd:c25:c25:94de:afe4/1272c19:dd:d9:dd:c25:c25:94de:afe5
2442c19:dd:d9:dd:c25:c25:94de:afe6/1272c19:dd:d9:dd:c25:c25:94de:afe7
2452c19:dd:d9:dd:c25:c25:94de:afe8/1272c19:dd:d9:dd:c25:c25:94de:afe9
2462c19:dd:d9:dd:c25:c25:94de:afea/1272c19:dd:d9:dd:c25:c25:94de:afeb
2472c19:dd:d9:dd:c25:c25:94de:afec/1272c19:dd:d9:dd:c25:c25:94de:afed
2482c19:dd:d9:dd:c25:c25:94de:afee/1272c19:dd:d9:dd:c25:c25:94de:afef
2492c19:dd:d9:dd:c25:c25:94de:aff0/1272c19:dd:d9:dd:c25:c25:94de:aff1
2502c19:dd:d9:dd:c25:c25:94de:aff2/1272c19:dd:d9:dd:c25:c25:94de:aff3
2512c19:dd:d9:dd:c25:c25:94de:aff4/1272c19:dd:d9:dd:c25:c25:94de:aff5
2522c19:dd:d9:dd:c25:c25:94de:aff6/1272c19:dd:d9:dd:c25:c25:94de:aff7
2532c19:dd:d9:dd:c25:c25:94de:aff8/1272c19:dd:d9:dd:c25:c25:94de:aff9
2542c19:dd:d9:dd:c25:c25:94de:affa/1272c19:dd:d9:dd:c25:c25:94de:affb
2552c19:dd:d9:dd:c25:c25:94de:affc/1272c19:dd:d9:dd:c25:c25:94de:affd
2562c19:dd:d9:dd:c25:c25:94de:affe/1272c19:dd:d9:dd:c25:c25:94de:afff

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.