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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/120
Addresses256
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:94de:ad00/120
First address
2c19:dd:d9:dd:c25:c25:94de:ad00
Last address
2c19:dd:d9:dd:c25:c25:94de:adff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:ad00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
d.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
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:94de:ad00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:ad00/1282c19:dd:d9:dd:c25:c25:94de:ad00
22c19:dd:d9:dd:c25:c25:94de:ad01/1282c19:dd:d9:dd:c25:c25:94de:ad01
32c19:dd:d9:dd:c25:c25:94de:ad02/1282c19:dd:d9:dd:c25:c25:94de:ad02
42c19:dd:d9:dd:c25:c25:94de:ad03/1282c19:dd:d9:dd:c25:c25:94de:ad03
52c19:dd:d9:dd:c25:c25:94de:ad04/1282c19:dd:d9:dd:c25:c25:94de:ad04
62c19:dd:d9:dd:c25:c25:94de:ad05/1282c19:dd:d9:dd:c25:c25:94de:ad05
72c19:dd:d9:dd:c25:c25:94de:ad06/1282c19:dd:d9:dd:c25:c25:94de:ad06
82c19:dd:d9:dd:c25:c25:94de:ad07/1282c19:dd:d9:dd:c25:c25:94de:ad07
92c19:dd:d9:dd:c25:c25:94de:ad08/1282c19:dd:d9:dd:c25:c25:94de:ad08
102c19:dd:d9:dd:c25:c25:94de:ad09/1282c19:dd:d9:dd:c25:c25:94de:ad09
112c19:dd:d9:dd:c25:c25:94de:ad0a/1282c19:dd:d9:dd:c25:c25:94de:ad0a
122c19:dd:d9:dd:c25:c25:94de:ad0b/1282c19:dd:d9:dd:c25:c25:94de:ad0b
132c19:dd:d9:dd:c25:c25:94de:ad0c/1282c19:dd:d9:dd:c25:c25:94de:ad0c
142c19:dd:d9:dd:c25:c25:94de:ad0d/1282c19:dd:d9:dd:c25:c25:94de:ad0d
152c19:dd:d9:dd:c25:c25:94de:ad0e/1282c19:dd:d9:dd:c25:c25:94de:ad0e
162c19:dd:d9:dd:c25:c25:94de:ad0f/1282c19:dd:d9:dd:c25:c25:94de:ad0f
172c19:dd:d9:dd:c25:c25:94de:ad10/1282c19:dd:d9:dd:c25:c25:94de:ad10
182c19:dd:d9:dd:c25:c25:94de:ad11/1282c19:dd:d9:dd:c25:c25:94de:ad11
192c19:dd:d9:dd:c25:c25:94de:ad12/1282c19:dd:d9:dd:c25:c25:94de:ad12
202c19:dd:d9:dd:c25:c25:94de:ad13/1282c19:dd:d9:dd:c25:c25:94de:ad13
212c19:dd:d9:dd:c25:c25:94de:ad14/1282c19:dd:d9:dd:c25:c25:94de:ad14
222c19:dd:d9:dd:c25:c25:94de:ad15/1282c19:dd:d9:dd:c25:c25:94de:ad15
232c19:dd:d9:dd:c25:c25:94de:ad16/1282c19:dd:d9:dd:c25:c25:94de:ad16
242c19:dd:d9:dd:c25:c25:94de:ad17/1282c19:dd:d9:dd:c25:c25:94de:ad17
252c19:dd:d9:dd:c25:c25:94de:ad18/1282c19:dd:d9:dd:c25:c25:94de:ad18
262c19:dd:d9:dd:c25:c25:94de:ad19/1282c19:dd:d9:dd:c25:c25:94de:ad19
272c19:dd:d9:dd:c25:c25:94de:ad1a/1282c19:dd:d9:dd:c25:c25:94de:ad1a
282c19:dd:d9:dd:c25:c25:94de:ad1b/1282c19:dd:d9:dd:c25:c25:94de:ad1b
292c19:dd:d9:dd:c25:c25:94de:ad1c/1282c19:dd:d9:dd:c25:c25:94de:ad1c
302c19:dd:d9:dd:c25:c25:94de:ad1d/1282c19:dd:d9:dd:c25:c25:94de:ad1d
312c19:dd:d9:dd:c25:c25:94de:ad1e/1282c19:dd:d9:dd:c25:c25:94de:ad1e
322c19:dd:d9:dd:c25:c25:94de:ad1f/1282c19:dd:d9:dd:c25:c25:94de:ad1f
332c19:dd:d9:dd:c25:c25:94de:ad20/1282c19:dd:d9:dd:c25:c25:94de:ad20
342c19:dd:d9:dd:c25:c25:94de:ad21/1282c19:dd:d9:dd:c25:c25:94de:ad21
352c19:dd:d9:dd:c25:c25:94de:ad22/1282c19:dd:d9:dd:c25:c25:94de:ad22
362c19:dd:d9:dd:c25:c25:94de:ad23/1282c19:dd:d9:dd:c25:c25:94de:ad23
372c19:dd:d9:dd:c25:c25:94de:ad24/1282c19:dd:d9:dd:c25:c25:94de:ad24
382c19:dd:d9:dd:c25:c25:94de:ad25/1282c19:dd:d9:dd:c25:c25:94de:ad25
392c19:dd:d9:dd:c25:c25:94de:ad26/1282c19:dd:d9:dd:c25:c25:94de:ad26
402c19:dd:d9:dd:c25:c25:94de:ad27/1282c19:dd:d9:dd:c25:c25:94de:ad27
412c19:dd:d9:dd:c25:c25:94de:ad28/1282c19:dd:d9:dd:c25:c25:94de:ad28
422c19:dd:d9:dd:c25:c25:94de:ad29/1282c19:dd:d9:dd:c25:c25:94de:ad29
432c19:dd:d9:dd:c25:c25:94de:ad2a/1282c19:dd:d9:dd:c25:c25:94de:ad2a
442c19:dd:d9:dd:c25:c25:94de:ad2b/1282c19:dd:d9:dd:c25:c25:94de:ad2b
452c19:dd:d9:dd:c25:c25:94de:ad2c/1282c19:dd:d9:dd:c25:c25:94de:ad2c
462c19:dd:d9:dd:c25:c25:94de:ad2d/1282c19:dd:d9:dd:c25:c25:94de:ad2d
472c19:dd:d9:dd:c25:c25:94de:ad2e/1282c19:dd:d9:dd:c25:c25:94de:ad2e
482c19:dd:d9:dd:c25:c25:94de:ad2f/1282c19:dd:d9:dd:c25:c25:94de:ad2f
492c19:dd:d9:dd:c25:c25:94de:ad30/1282c19:dd:d9:dd:c25:c25:94de:ad30
502c19:dd:d9:dd:c25:c25:94de:ad31/1282c19:dd:d9:dd:c25:c25:94de:ad31
512c19:dd:d9:dd:c25:c25:94de:ad32/1282c19:dd:d9:dd:c25:c25:94de:ad32
522c19:dd:d9:dd:c25:c25:94de:ad33/1282c19:dd:d9:dd:c25:c25:94de:ad33
532c19:dd:d9:dd:c25:c25:94de:ad34/1282c19:dd:d9:dd:c25:c25:94de:ad34
542c19:dd:d9:dd:c25:c25:94de:ad35/1282c19:dd:d9:dd:c25:c25:94de:ad35
552c19:dd:d9:dd:c25:c25:94de:ad36/1282c19:dd:d9:dd:c25:c25:94de:ad36
562c19:dd:d9:dd:c25:c25:94de:ad37/1282c19:dd:d9:dd:c25:c25:94de:ad37
572c19:dd:d9:dd:c25:c25:94de:ad38/1282c19:dd:d9:dd:c25:c25:94de:ad38
582c19:dd:d9:dd:c25:c25:94de:ad39/1282c19:dd:d9:dd:c25:c25:94de:ad39
592c19:dd:d9:dd:c25:c25:94de:ad3a/1282c19:dd:d9:dd:c25:c25:94de:ad3a
602c19:dd:d9:dd:c25:c25:94de:ad3b/1282c19:dd:d9:dd:c25:c25:94de:ad3b
612c19:dd:d9:dd:c25:c25:94de:ad3c/1282c19:dd:d9:dd:c25:c25:94de:ad3c
622c19:dd:d9:dd:c25:c25:94de:ad3d/1282c19:dd:d9:dd:c25:c25:94de:ad3d
632c19:dd:d9:dd:c25:c25:94de:ad3e/1282c19:dd:d9:dd:c25:c25:94de:ad3e
642c19:dd:d9:dd:c25:c25:94de:ad3f/1282c19:dd:d9:dd:c25:c25:94de:ad3f
652c19:dd:d9:dd:c25:c25:94de:ad40/1282c19:dd:d9:dd:c25:c25:94de:ad40
662c19:dd:d9:dd:c25:c25:94de:ad41/1282c19:dd:d9:dd:c25:c25:94de:ad41
672c19:dd:d9:dd:c25:c25:94de:ad42/1282c19:dd:d9:dd:c25:c25:94de:ad42
682c19:dd:d9:dd:c25:c25:94de:ad43/1282c19:dd:d9:dd:c25:c25:94de:ad43
692c19:dd:d9:dd:c25:c25:94de:ad44/1282c19:dd:d9:dd:c25:c25:94de:ad44
702c19:dd:d9:dd:c25:c25:94de:ad45/1282c19:dd:d9:dd:c25:c25:94de:ad45
712c19:dd:d9:dd:c25:c25:94de:ad46/1282c19:dd:d9:dd:c25:c25:94de:ad46
722c19:dd:d9:dd:c25:c25:94de:ad47/1282c19:dd:d9:dd:c25:c25:94de:ad47
732c19:dd:d9:dd:c25:c25:94de:ad48/1282c19:dd:d9:dd:c25:c25:94de:ad48
742c19:dd:d9:dd:c25:c25:94de:ad49/1282c19:dd:d9:dd:c25:c25:94de:ad49
752c19:dd:d9:dd:c25:c25:94de:ad4a/1282c19:dd:d9:dd:c25:c25:94de:ad4a
762c19:dd:d9:dd:c25:c25:94de:ad4b/1282c19:dd:d9:dd:c25:c25:94de:ad4b
772c19:dd:d9:dd:c25:c25:94de:ad4c/1282c19:dd:d9:dd:c25:c25:94de:ad4c
782c19:dd:d9:dd:c25:c25:94de:ad4d/1282c19:dd:d9:dd:c25:c25:94de:ad4d
792c19:dd:d9:dd:c25:c25:94de:ad4e/1282c19:dd:d9:dd:c25:c25:94de:ad4e
802c19:dd:d9:dd:c25:c25:94de:ad4f/1282c19:dd:d9:dd:c25:c25:94de:ad4f
812c19:dd:d9:dd:c25:c25:94de:ad50/1282c19:dd:d9:dd:c25:c25:94de:ad50
822c19:dd:d9:dd:c25:c25:94de:ad51/1282c19:dd:d9:dd:c25:c25:94de:ad51
832c19:dd:d9:dd:c25:c25:94de:ad52/1282c19:dd:d9:dd:c25:c25:94de:ad52
842c19:dd:d9:dd:c25:c25:94de:ad53/1282c19:dd:d9:dd:c25:c25:94de:ad53
852c19:dd:d9:dd:c25:c25:94de:ad54/1282c19:dd:d9:dd:c25:c25:94de:ad54
862c19:dd:d9:dd:c25:c25:94de:ad55/1282c19:dd:d9:dd:c25:c25:94de:ad55
872c19:dd:d9:dd:c25:c25:94de:ad56/1282c19:dd:d9:dd:c25:c25:94de:ad56
882c19:dd:d9:dd:c25:c25:94de:ad57/1282c19:dd:d9:dd:c25:c25:94de:ad57
892c19:dd:d9:dd:c25:c25:94de:ad58/1282c19:dd:d9:dd:c25:c25:94de:ad58
902c19:dd:d9:dd:c25:c25:94de:ad59/1282c19:dd:d9:dd:c25:c25:94de:ad59
912c19:dd:d9:dd:c25:c25:94de:ad5a/1282c19:dd:d9:dd:c25:c25:94de:ad5a
922c19:dd:d9:dd:c25:c25:94de:ad5b/1282c19:dd:d9:dd:c25:c25:94de:ad5b
932c19:dd:d9:dd:c25:c25:94de:ad5c/1282c19:dd:d9:dd:c25:c25:94de:ad5c
942c19:dd:d9:dd:c25:c25:94de:ad5d/1282c19:dd:d9:dd:c25:c25:94de:ad5d
952c19:dd:d9:dd:c25:c25:94de:ad5e/1282c19:dd:d9:dd:c25:c25:94de:ad5e
962c19:dd:d9:dd:c25:c25:94de:ad5f/1282c19:dd:d9:dd:c25:c25:94de:ad5f
972c19:dd:d9:dd:c25:c25:94de:ad60/1282c19:dd:d9:dd:c25:c25:94de:ad60
982c19:dd:d9:dd:c25:c25:94de:ad61/1282c19:dd:d9:dd:c25:c25:94de:ad61
992c19:dd:d9:dd:c25:c25:94de:ad62/1282c19:dd:d9:dd:c25:c25:94de:ad62
1002c19:dd:d9:dd:c25:c25:94de:ad63/1282c19:dd:d9:dd:c25:c25:94de:ad63
1012c19:dd:d9:dd:c25:c25:94de:ad64/1282c19:dd:d9:dd:c25:c25:94de:ad64
1022c19:dd:d9:dd:c25:c25:94de:ad65/1282c19:dd:d9:dd:c25:c25:94de:ad65
1032c19:dd:d9:dd:c25:c25:94de:ad66/1282c19:dd:d9:dd:c25:c25:94de:ad66
1042c19:dd:d9:dd:c25:c25:94de:ad67/1282c19:dd:d9:dd:c25:c25:94de:ad67
1052c19:dd:d9:dd:c25:c25:94de:ad68/1282c19:dd:d9:dd:c25:c25:94de:ad68
1062c19:dd:d9:dd:c25:c25:94de:ad69/1282c19:dd:d9:dd:c25:c25:94de:ad69
1072c19:dd:d9:dd:c25:c25:94de:ad6a/1282c19:dd:d9:dd:c25:c25:94de:ad6a
1082c19:dd:d9:dd:c25:c25:94de:ad6b/1282c19:dd:d9:dd:c25:c25:94de:ad6b
1092c19:dd:d9:dd:c25:c25:94de:ad6c/1282c19:dd:d9:dd:c25:c25:94de:ad6c
1102c19:dd:d9:dd:c25:c25:94de:ad6d/1282c19:dd:d9:dd:c25:c25:94de:ad6d
1112c19:dd:d9:dd:c25:c25:94de:ad6e/1282c19:dd:d9:dd:c25:c25:94de:ad6e
1122c19:dd:d9:dd:c25:c25:94de:ad6f/1282c19:dd:d9:dd:c25:c25:94de:ad6f
1132c19:dd:d9:dd:c25:c25:94de:ad70/1282c19:dd:d9:dd:c25:c25:94de:ad70
1142c19:dd:d9:dd:c25:c25:94de:ad71/1282c19:dd:d9:dd:c25:c25:94de:ad71
1152c19:dd:d9:dd:c25:c25:94de:ad72/1282c19:dd:d9:dd:c25:c25:94de:ad72
1162c19:dd:d9:dd:c25:c25:94de:ad73/1282c19:dd:d9:dd:c25:c25:94de:ad73
1172c19:dd:d9:dd:c25:c25:94de:ad74/1282c19:dd:d9:dd:c25:c25:94de:ad74
1182c19:dd:d9:dd:c25:c25:94de:ad75/1282c19:dd:d9:dd:c25:c25:94de:ad75
1192c19:dd:d9:dd:c25:c25:94de:ad76/1282c19:dd:d9:dd:c25:c25:94de:ad76
1202c19:dd:d9:dd:c25:c25:94de:ad77/1282c19:dd:d9:dd:c25:c25:94de:ad77
1212c19:dd:d9:dd:c25:c25:94de:ad78/1282c19:dd:d9:dd:c25:c25:94de:ad78
1222c19:dd:d9:dd:c25:c25:94de:ad79/1282c19:dd:d9:dd:c25:c25:94de:ad79
1232c19:dd:d9:dd:c25:c25:94de:ad7a/1282c19:dd:d9:dd:c25:c25:94de:ad7a
1242c19:dd:d9:dd:c25:c25:94de:ad7b/1282c19:dd:d9:dd:c25:c25:94de:ad7b
1252c19:dd:d9:dd:c25:c25:94de:ad7c/1282c19:dd:d9:dd:c25:c25:94de:ad7c
1262c19:dd:d9:dd:c25:c25:94de:ad7d/1282c19:dd:d9:dd:c25:c25:94de:ad7d
1272c19:dd:d9:dd:c25:c25:94de:ad7e/1282c19:dd:d9:dd:c25:c25:94de:ad7e
1282c19:dd:d9:dd:c25:c25:94de:ad7f/1282c19:dd:d9:dd:c25:c25:94de:ad7f
1292c19:dd:d9:dd:c25:c25:94de:ad80/1282c19:dd:d9:dd:c25:c25:94de:ad80
1302c19:dd:d9:dd:c25:c25:94de:ad81/1282c19:dd:d9:dd:c25:c25:94de:ad81
1312c19:dd:d9:dd:c25:c25:94de:ad82/1282c19:dd:d9:dd:c25:c25:94de:ad82
1322c19:dd:d9:dd:c25:c25:94de:ad83/1282c19:dd:d9:dd:c25:c25:94de:ad83
1332c19:dd:d9:dd:c25:c25:94de:ad84/1282c19:dd:d9:dd:c25:c25:94de:ad84
1342c19:dd:d9:dd:c25:c25:94de:ad85/1282c19:dd:d9:dd:c25:c25:94de:ad85
1352c19:dd:d9:dd:c25:c25:94de:ad86/1282c19:dd:d9:dd:c25:c25:94de:ad86
1362c19:dd:d9:dd:c25:c25:94de:ad87/1282c19:dd:d9:dd:c25:c25:94de:ad87
1372c19:dd:d9:dd:c25:c25:94de:ad88/1282c19:dd:d9:dd:c25:c25:94de:ad88
1382c19:dd:d9:dd:c25:c25:94de:ad89/1282c19:dd:d9:dd:c25:c25:94de:ad89
1392c19:dd:d9:dd:c25:c25:94de:ad8a/1282c19:dd:d9:dd:c25:c25:94de:ad8a
1402c19:dd:d9:dd:c25:c25:94de:ad8b/1282c19:dd:d9:dd:c25:c25:94de:ad8b
1412c19:dd:d9:dd:c25:c25:94de:ad8c/1282c19:dd:d9:dd:c25:c25:94de:ad8c
1422c19:dd:d9:dd:c25:c25:94de:ad8d/1282c19:dd:d9:dd:c25:c25:94de:ad8d
1432c19:dd:d9:dd:c25:c25:94de:ad8e/1282c19:dd:d9:dd:c25:c25:94de:ad8e
1442c19:dd:d9:dd:c25:c25:94de:ad8f/1282c19:dd:d9:dd:c25:c25:94de:ad8f
1452c19:dd:d9:dd:c25:c25:94de:ad90/1282c19:dd:d9:dd:c25:c25:94de:ad90
1462c19:dd:d9:dd:c25:c25:94de:ad91/1282c19:dd:d9:dd:c25:c25:94de:ad91
1472c19:dd:d9:dd:c25:c25:94de:ad92/1282c19:dd:d9:dd:c25:c25:94de:ad92
1482c19:dd:d9:dd:c25:c25:94de:ad93/1282c19:dd:d9:dd:c25:c25:94de:ad93
1492c19:dd:d9:dd:c25:c25:94de:ad94/1282c19:dd:d9:dd:c25:c25:94de:ad94
1502c19:dd:d9:dd:c25:c25:94de:ad95/1282c19:dd:d9:dd:c25:c25:94de:ad95
1512c19:dd:d9:dd:c25:c25:94de:ad96/1282c19:dd:d9:dd:c25:c25:94de:ad96
1522c19:dd:d9:dd:c25:c25:94de:ad97/1282c19:dd:d9:dd:c25:c25:94de:ad97
1532c19:dd:d9:dd:c25:c25:94de:ad98/1282c19:dd:d9:dd:c25:c25:94de:ad98
1542c19:dd:d9:dd:c25:c25:94de:ad99/1282c19:dd:d9:dd:c25:c25:94de:ad99
1552c19:dd:d9:dd:c25:c25:94de:ad9a/1282c19:dd:d9:dd:c25:c25:94de:ad9a
1562c19:dd:d9:dd:c25:c25:94de:ad9b/1282c19:dd:d9:dd:c25:c25:94de:ad9b
1572c19:dd:d9:dd:c25:c25:94de:ad9c/1282c19:dd:d9:dd:c25:c25:94de:ad9c
1582c19:dd:d9:dd:c25:c25:94de:ad9d/1282c19:dd:d9:dd:c25:c25:94de:ad9d
1592c19:dd:d9:dd:c25:c25:94de:ad9e/1282c19:dd:d9:dd:c25:c25:94de:ad9e
1602c19:dd:d9:dd:c25:c25:94de:ad9f/1282c19:dd:d9:dd:c25:c25:94de:ad9f
1612c19:dd:d9:dd:c25:c25:94de:ada0/1282c19:dd:d9:dd:c25:c25:94de:ada0
1622c19:dd:d9:dd:c25:c25:94de:ada1/1282c19:dd:d9:dd:c25:c25:94de:ada1
1632c19:dd:d9:dd:c25:c25:94de:ada2/1282c19:dd:d9:dd:c25:c25:94de:ada2
1642c19:dd:d9:dd:c25:c25:94de:ada3/1282c19:dd:d9:dd:c25:c25:94de:ada3
1652c19:dd:d9:dd:c25:c25:94de:ada4/1282c19:dd:d9:dd:c25:c25:94de:ada4
1662c19:dd:d9:dd:c25:c25:94de:ada5/1282c19:dd:d9:dd:c25:c25:94de:ada5
1672c19:dd:d9:dd:c25:c25:94de:ada6/1282c19:dd:d9:dd:c25:c25:94de:ada6
1682c19:dd:d9:dd:c25:c25:94de:ada7/1282c19:dd:d9:dd:c25:c25:94de:ada7
1692c19:dd:d9:dd:c25:c25:94de:ada8/1282c19:dd:d9:dd:c25:c25:94de:ada8
1702c19:dd:d9:dd:c25:c25:94de:ada9/1282c19:dd:d9:dd:c25:c25:94de:ada9
1712c19:dd:d9:dd:c25:c25:94de:adaa/1282c19:dd:d9:dd:c25:c25:94de:adaa
1722c19:dd:d9:dd:c25:c25:94de:adab/1282c19:dd:d9:dd:c25:c25:94de:adab
1732c19:dd:d9:dd:c25:c25:94de:adac/1282c19:dd:d9:dd:c25:c25:94de:adac
1742c19:dd:d9:dd:c25:c25:94de:adad/1282c19:dd:d9:dd:c25:c25:94de:adad
1752c19:dd:d9:dd:c25:c25:94de:adae/1282c19:dd:d9:dd:c25:c25:94de:adae
1762c19:dd:d9:dd:c25:c25:94de:adaf/1282c19:dd:d9:dd:c25:c25:94de:adaf
1772c19:dd:d9:dd:c25:c25:94de:adb0/1282c19:dd:d9:dd:c25:c25:94de:adb0
1782c19:dd:d9:dd:c25:c25:94de:adb1/1282c19:dd:d9:dd:c25:c25:94de:adb1
1792c19:dd:d9:dd:c25:c25:94de:adb2/1282c19:dd:d9:dd:c25:c25:94de:adb2
1802c19:dd:d9:dd:c25:c25:94de:adb3/1282c19:dd:d9:dd:c25:c25:94de:adb3
1812c19:dd:d9:dd:c25:c25:94de:adb4/1282c19:dd:d9:dd:c25:c25:94de:adb4
1822c19:dd:d9:dd:c25:c25:94de:adb5/1282c19:dd:d9:dd:c25:c25:94de:adb5
1832c19:dd:d9:dd:c25:c25:94de:adb6/1282c19:dd:d9:dd:c25:c25:94de:adb6
1842c19:dd:d9:dd:c25:c25:94de:adb7/1282c19:dd:d9:dd:c25:c25:94de:adb7
1852c19:dd:d9:dd:c25:c25:94de:adb8/1282c19:dd:d9:dd:c25:c25:94de:adb8
1862c19:dd:d9:dd:c25:c25:94de:adb9/1282c19:dd:d9:dd:c25:c25:94de:adb9
1872c19:dd:d9:dd:c25:c25:94de:adba/1282c19:dd:d9:dd:c25:c25:94de:adba
1882c19:dd:d9:dd:c25:c25:94de:adbb/1282c19:dd:d9:dd:c25:c25:94de:adbb
1892c19:dd:d9:dd:c25:c25:94de:adbc/1282c19:dd:d9:dd:c25:c25:94de:adbc
1902c19:dd:d9:dd:c25:c25:94de:adbd/1282c19:dd:d9:dd:c25:c25:94de:adbd
1912c19:dd:d9:dd:c25:c25:94de:adbe/1282c19:dd:d9:dd:c25:c25:94de:adbe
1922c19:dd:d9:dd:c25:c25:94de:adbf/1282c19:dd:d9:dd:c25:c25:94de:adbf
1932c19:dd:d9:dd:c25:c25:94de:adc0/1282c19:dd:d9:dd:c25:c25:94de:adc0
1942c19:dd:d9:dd:c25:c25:94de:adc1/1282c19:dd:d9:dd:c25:c25:94de:adc1
1952c19:dd:d9:dd:c25:c25:94de:adc2/1282c19:dd:d9:dd:c25:c25:94de:adc2
1962c19:dd:d9:dd:c25:c25:94de:adc3/1282c19:dd:d9:dd:c25:c25:94de:adc3
1972c19:dd:d9:dd:c25:c25:94de:adc4/1282c19:dd:d9:dd:c25:c25:94de:adc4
1982c19:dd:d9:dd:c25:c25:94de:adc5/1282c19:dd:d9:dd:c25:c25:94de:adc5
1992c19:dd:d9:dd:c25:c25:94de:adc6/1282c19:dd:d9:dd:c25:c25:94de:adc6
2002c19:dd:d9:dd:c25:c25:94de:adc7/1282c19:dd:d9:dd:c25:c25:94de:adc7
2012c19:dd:d9:dd:c25:c25:94de:adc8/1282c19:dd:d9:dd:c25:c25:94de:adc8
2022c19:dd:d9:dd:c25:c25:94de:adc9/1282c19:dd:d9:dd:c25:c25:94de:adc9
2032c19:dd:d9:dd:c25:c25:94de:adca/1282c19:dd:d9:dd:c25:c25:94de:adca
2042c19:dd:d9:dd:c25:c25:94de:adcb/1282c19:dd:d9:dd:c25:c25:94de:adcb
2052c19:dd:d9:dd:c25:c25:94de:adcc/1282c19:dd:d9:dd:c25:c25:94de:adcc
2062c19:dd:d9:dd:c25:c25:94de:adcd/1282c19:dd:d9:dd:c25:c25:94de:adcd
2072c19:dd:d9:dd:c25:c25:94de:adce/1282c19:dd:d9:dd:c25:c25:94de:adce
2082c19:dd:d9:dd:c25:c25:94de:adcf/1282c19:dd:d9:dd:c25:c25:94de:adcf
2092c19:dd:d9:dd:c25:c25:94de:add0/1282c19:dd:d9:dd:c25:c25:94de:add0
2102c19:dd:d9:dd:c25:c25:94de:add1/1282c19:dd:d9:dd:c25:c25:94de:add1
2112c19:dd:d9:dd:c25:c25:94de:add2/1282c19:dd:d9:dd:c25:c25:94de:add2
2122c19:dd:d9:dd:c25:c25:94de:add3/1282c19:dd:d9:dd:c25:c25:94de:add3
2132c19:dd:d9:dd:c25:c25:94de:add4/1282c19:dd:d9:dd:c25:c25:94de:add4
2142c19:dd:d9:dd:c25:c25:94de:add5/1282c19:dd:d9:dd:c25:c25:94de:add5
2152c19:dd:d9:dd:c25:c25:94de:add6/1282c19:dd:d9:dd:c25:c25:94de:add6
2162c19:dd:d9:dd:c25:c25:94de:add7/1282c19:dd:d9:dd:c25:c25:94de:add7
2172c19:dd:d9:dd:c25:c25:94de:add8/1282c19:dd:d9:dd:c25:c25:94de:add8
2182c19:dd:d9:dd:c25:c25:94de:add9/1282c19:dd:d9:dd:c25:c25:94de:add9
2192c19:dd:d9:dd:c25:c25:94de:adda/1282c19:dd:d9:dd:c25:c25:94de:adda
2202c19:dd:d9:dd:c25:c25:94de:addb/1282c19:dd:d9:dd:c25:c25:94de:addb
2212c19:dd:d9:dd:c25:c25:94de:addc/1282c19:dd:d9:dd:c25:c25:94de:addc
2222c19:dd:d9:dd:c25:c25:94de:addd/1282c19:dd:d9:dd:c25:c25:94de:addd
2232c19:dd:d9:dd:c25:c25:94de:adde/1282c19:dd:d9:dd:c25:c25:94de:adde
2242c19:dd:d9:dd:c25:c25:94de:addf/1282c19:dd:d9:dd:c25:c25:94de:addf
2252c19:dd:d9:dd:c25:c25:94de:ade0/1282c19:dd:d9:dd:c25:c25:94de:ade0
2262c19:dd:d9:dd:c25:c25:94de:ade1/1282c19:dd:d9:dd:c25:c25:94de:ade1
2272c19:dd:d9:dd:c25:c25:94de:ade2/1282c19:dd:d9:dd:c25:c25:94de:ade2
2282c19:dd:d9:dd:c25:c25:94de:ade3/1282c19:dd:d9:dd:c25:c25:94de:ade3
2292c19:dd:d9:dd:c25:c25:94de:ade4/1282c19:dd:d9:dd:c25:c25:94de:ade4
2302c19:dd:d9:dd:c25:c25:94de:ade5/1282c19:dd:d9:dd:c25:c25:94de:ade5
2312c19:dd:d9:dd:c25:c25:94de:ade6/1282c19:dd:d9:dd:c25:c25:94de:ade6
2322c19:dd:d9:dd:c25:c25:94de:ade7/1282c19:dd:d9:dd:c25:c25:94de:ade7
2332c19:dd:d9:dd:c25:c25:94de:ade8/1282c19:dd:d9:dd:c25:c25:94de:ade8
2342c19:dd:d9:dd:c25:c25:94de:ade9/1282c19:dd:d9:dd:c25:c25:94de:ade9
2352c19:dd:d9:dd:c25:c25:94de:adea/1282c19:dd:d9:dd:c25:c25:94de:adea
2362c19:dd:d9:dd:c25:c25:94de:adeb/1282c19:dd:d9:dd:c25:c25:94de:adeb
2372c19:dd:d9:dd:c25:c25:94de:adec/1282c19:dd:d9:dd:c25:c25:94de:adec
2382c19:dd:d9:dd:c25:c25:94de:aded/1282c19:dd:d9:dd:c25:c25:94de:aded
2392c19:dd:d9:dd:c25:c25:94de:adee/1282c19:dd:d9:dd:c25:c25:94de:adee
2402c19:dd:d9:dd:c25:c25:94de:adef/1282c19:dd:d9:dd:c25:c25:94de:adef
2412c19:dd:d9:dd:c25:c25:94de:adf0/1282c19:dd:d9:dd:c25:c25:94de:adf0
2422c19:dd:d9:dd:c25:c25:94de:adf1/1282c19:dd:d9:dd:c25:c25:94de:adf1
2432c19:dd:d9:dd:c25:c25:94de:adf2/1282c19:dd:d9:dd:c25:c25:94de:adf2
2442c19:dd:d9:dd:c25:c25:94de:adf3/1282c19:dd:d9:dd:c25:c25:94de:adf3
2452c19:dd:d9:dd:c25:c25:94de:adf4/1282c19:dd:d9:dd:c25:c25:94de:adf4
2462c19:dd:d9:dd:c25:c25:94de:adf5/1282c19:dd:d9:dd:c25:c25:94de:adf5
2472c19:dd:d9:dd:c25:c25:94de:adf6/1282c19:dd:d9:dd:c25:c25:94de:adf6
2482c19:dd:d9:dd:c25:c25:94de:adf7/1282c19:dd:d9:dd:c25:c25:94de:adf7
2492c19:dd:d9:dd:c25:c25:94de:adf8/1282c19:dd:d9:dd:c25:c25:94de:adf8
2502c19:dd:d9:dd:c25:c25:94de:adf9/1282c19:dd:d9:dd:c25:c25:94de:adf9
2512c19:dd:d9:dd:c25:c25:94de:adfa/1282c19:dd:d9:dd:c25:c25:94de:adfa
2522c19:dd:d9:dd:c25:c25:94de:adfb/1282c19:dd:d9:dd:c25:c25:94de:adfb
2532c19:dd:d9:dd:c25:c25:94de:adfc/1282c19:dd:d9:dd:c25:c25:94de:adfc
2542c19:dd:d9:dd:c25:c25:94de:adfd/1282c19:dd:d9:dd:c25:c25:94de:adfd
2552c19:dd:d9:dd:c25:c25:94de:adfe/1282c19:dd:d9:dd:c25:c25:94de:adfe
2562c19:dd:d9:dd:c25:c25:94de:adff/1282c19:dd:d9:dd:c25:c25:94de:adff

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.