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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:ed00/120
First address
2c19:dd:d9:dd:c25:c25:94de:ed00
Last address
2c19:dd:d9:dd:c25:c25:94de:edff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:ed00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
d.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
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:94de:ed00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:ed00/1282c19:dd:d9:dd:c25:c25:94de:ed00
22c19:dd:d9:dd:c25:c25:94de:ed01/1282c19:dd:d9:dd:c25:c25:94de:ed01
32c19:dd:d9:dd:c25:c25:94de:ed02/1282c19:dd:d9:dd:c25:c25:94de:ed02
42c19:dd:d9:dd:c25:c25:94de:ed03/1282c19:dd:d9:dd:c25:c25:94de:ed03
52c19:dd:d9:dd:c25:c25:94de:ed04/1282c19:dd:d9:dd:c25:c25:94de:ed04
62c19:dd:d9:dd:c25:c25:94de:ed05/1282c19:dd:d9:dd:c25:c25:94de:ed05
72c19:dd:d9:dd:c25:c25:94de:ed06/1282c19:dd:d9:dd:c25:c25:94de:ed06
82c19:dd:d9:dd:c25:c25:94de:ed07/1282c19:dd:d9:dd:c25:c25:94de:ed07
92c19:dd:d9:dd:c25:c25:94de:ed08/1282c19:dd:d9:dd:c25:c25:94de:ed08
102c19:dd:d9:dd:c25:c25:94de:ed09/1282c19:dd:d9:dd:c25:c25:94de:ed09
112c19:dd:d9:dd:c25:c25:94de:ed0a/1282c19:dd:d9:dd:c25:c25:94de:ed0a
122c19:dd:d9:dd:c25:c25:94de:ed0b/1282c19:dd:d9:dd:c25:c25:94de:ed0b
132c19:dd:d9:dd:c25:c25:94de:ed0c/1282c19:dd:d9:dd:c25:c25:94de:ed0c
142c19:dd:d9:dd:c25:c25:94de:ed0d/1282c19:dd:d9:dd:c25:c25:94de:ed0d
152c19:dd:d9:dd:c25:c25:94de:ed0e/1282c19:dd:d9:dd:c25:c25:94de:ed0e
162c19:dd:d9:dd:c25:c25:94de:ed0f/1282c19:dd:d9:dd:c25:c25:94de:ed0f
172c19:dd:d9:dd:c25:c25:94de:ed10/1282c19:dd:d9:dd:c25:c25:94de:ed10
182c19:dd:d9:dd:c25:c25:94de:ed11/1282c19:dd:d9:dd:c25:c25:94de:ed11
192c19:dd:d9:dd:c25:c25:94de:ed12/1282c19:dd:d9:dd:c25:c25:94de:ed12
202c19:dd:d9:dd:c25:c25:94de:ed13/1282c19:dd:d9:dd:c25:c25:94de:ed13
212c19:dd:d9:dd:c25:c25:94de:ed14/1282c19:dd:d9:dd:c25:c25:94de:ed14
222c19:dd:d9:dd:c25:c25:94de:ed15/1282c19:dd:d9:dd:c25:c25:94de:ed15
232c19:dd:d9:dd:c25:c25:94de:ed16/1282c19:dd:d9:dd:c25:c25:94de:ed16
242c19:dd:d9:dd:c25:c25:94de:ed17/1282c19:dd:d9:dd:c25:c25:94de:ed17
252c19:dd:d9:dd:c25:c25:94de:ed18/1282c19:dd:d9:dd:c25:c25:94de:ed18
262c19:dd:d9:dd:c25:c25:94de:ed19/1282c19:dd:d9:dd:c25:c25:94de:ed19
272c19:dd:d9:dd:c25:c25:94de:ed1a/1282c19:dd:d9:dd:c25:c25:94de:ed1a
282c19:dd:d9:dd:c25:c25:94de:ed1b/1282c19:dd:d9:dd:c25:c25:94de:ed1b
292c19:dd:d9:dd:c25:c25:94de:ed1c/1282c19:dd:d9:dd:c25:c25:94de:ed1c
302c19:dd:d9:dd:c25:c25:94de:ed1d/1282c19:dd:d9:dd:c25:c25:94de:ed1d
312c19:dd:d9:dd:c25:c25:94de:ed1e/1282c19:dd:d9:dd:c25:c25:94de:ed1e
322c19:dd:d9:dd:c25:c25:94de:ed1f/1282c19:dd:d9:dd:c25:c25:94de:ed1f
332c19:dd:d9:dd:c25:c25:94de:ed20/1282c19:dd:d9:dd:c25:c25:94de:ed20
342c19:dd:d9:dd:c25:c25:94de:ed21/1282c19:dd:d9:dd:c25:c25:94de:ed21
352c19:dd:d9:dd:c25:c25:94de:ed22/1282c19:dd:d9:dd:c25:c25:94de:ed22
362c19:dd:d9:dd:c25:c25:94de:ed23/1282c19:dd:d9:dd:c25:c25:94de:ed23
372c19:dd:d9:dd:c25:c25:94de:ed24/1282c19:dd:d9:dd:c25:c25:94de:ed24
382c19:dd:d9:dd:c25:c25:94de:ed25/1282c19:dd:d9:dd:c25:c25:94de:ed25
392c19:dd:d9:dd:c25:c25:94de:ed26/1282c19:dd:d9:dd:c25:c25:94de:ed26
402c19:dd:d9:dd:c25:c25:94de:ed27/1282c19:dd:d9:dd:c25:c25:94de:ed27
412c19:dd:d9:dd:c25:c25:94de:ed28/1282c19:dd:d9:dd:c25:c25:94de:ed28
422c19:dd:d9:dd:c25:c25:94de:ed29/1282c19:dd:d9:dd:c25:c25:94de:ed29
432c19:dd:d9:dd:c25:c25:94de:ed2a/1282c19:dd:d9:dd:c25:c25:94de:ed2a
442c19:dd:d9:dd:c25:c25:94de:ed2b/1282c19:dd:d9:dd:c25:c25:94de:ed2b
452c19:dd:d9:dd:c25:c25:94de:ed2c/1282c19:dd:d9:dd:c25:c25:94de:ed2c
462c19:dd:d9:dd:c25:c25:94de:ed2d/1282c19:dd:d9:dd:c25:c25:94de:ed2d
472c19:dd:d9:dd:c25:c25:94de:ed2e/1282c19:dd:d9:dd:c25:c25:94de:ed2e
482c19:dd:d9:dd:c25:c25:94de:ed2f/1282c19:dd:d9:dd:c25:c25:94de:ed2f
492c19:dd:d9:dd:c25:c25:94de:ed30/1282c19:dd:d9:dd:c25:c25:94de:ed30
502c19:dd:d9:dd:c25:c25:94de:ed31/1282c19:dd:d9:dd:c25:c25:94de:ed31
512c19:dd:d9:dd:c25:c25:94de:ed32/1282c19:dd:d9:dd:c25:c25:94de:ed32
522c19:dd:d9:dd:c25:c25:94de:ed33/1282c19:dd:d9:dd:c25:c25:94de:ed33
532c19:dd:d9:dd:c25:c25:94de:ed34/1282c19:dd:d9:dd:c25:c25:94de:ed34
542c19:dd:d9:dd:c25:c25:94de:ed35/1282c19:dd:d9:dd:c25:c25:94de:ed35
552c19:dd:d9:dd:c25:c25:94de:ed36/1282c19:dd:d9:dd:c25:c25:94de:ed36
562c19:dd:d9:dd:c25:c25:94de:ed37/1282c19:dd:d9:dd:c25:c25:94de:ed37
572c19:dd:d9:dd:c25:c25:94de:ed38/1282c19:dd:d9:dd:c25:c25:94de:ed38
582c19:dd:d9:dd:c25:c25:94de:ed39/1282c19:dd:d9:dd:c25:c25:94de:ed39
592c19:dd:d9:dd:c25:c25:94de:ed3a/1282c19:dd:d9:dd:c25:c25:94de:ed3a
602c19:dd:d9:dd:c25:c25:94de:ed3b/1282c19:dd:d9:dd:c25:c25:94de:ed3b
612c19:dd:d9:dd:c25:c25:94de:ed3c/1282c19:dd:d9:dd:c25:c25:94de:ed3c
622c19:dd:d9:dd:c25:c25:94de:ed3d/1282c19:dd:d9:dd:c25:c25:94de:ed3d
632c19:dd:d9:dd:c25:c25:94de:ed3e/1282c19:dd:d9:dd:c25:c25:94de:ed3e
642c19:dd:d9:dd:c25:c25:94de:ed3f/1282c19:dd:d9:dd:c25:c25:94de:ed3f
652c19:dd:d9:dd:c25:c25:94de:ed40/1282c19:dd:d9:dd:c25:c25:94de:ed40
662c19:dd:d9:dd:c25:c25:94de:ed41/1282c19:dd:d9:dd:c25:c25:94de:ed41
672c19:dd:d9:dd:c25:c25:94de:ed42/1282c19:dd:d9:dd:c25:c25:94de:ed42
682c19:dd:d9:dd:c25:c25:94de:ed43/1282c19:dd:d9:dd:c25:c25:94de:ed43
692c19:dd:d9:dd:c25:c25:94de:ed44/1282c19:dd:d9:dd:c25:c25:94de:ed44
702c19:dd:d9:dd:c25:c25:94de:ed45/1282c19:dd:d9:dd:c25:c25:94de:ed45
712c19:dd:d9:dd:c25:c25:94de:ed46/1282c19:dd:d9:dd:c25:c25:94de:ed46
722c19:dd:d9:dd:c25:c25:94de:ed47/1282c19:dd:d9:dd:c25:c25:94de:ed47
732c19:dd:d9:dd:c25:c25:94de:ed48/1282c19:dd:d9:dd:c25:c25:94de:ed48
742c19:dd:d9:dd:c25:c25:94de:ed49/1282c19:dd:d9:dd:c25:c25:94de:ed49
752c19:dd:d9:dd:c25:c25:94de:ed4a/1282c19:dd:d9:dd:c25:c25:94de:ed4a
762c19:dd:d9:dd:c25:c25:94de:ed4b/1282c19:dd:d9:dd:c25:c25:94de:ed4b
772c19:dd:d9:dd:c25:c25:94de:ed4c/1282c19:dd:d9:dd:c25:c25:94de:ed4c
782c19:dd:d9:dd:c25:c25:94de:ed4d/1282c19:dd:d9:dd:c25:c25:94de:ed4d
792c19:dd:d9:dd:c25:c25:94de:ed4e/1282c19:dd:d9:dd:c25:c25:94de:ed4e
802c19:dd:d9:dd:c25:c25:94de:ed4f/1282c19:dd:d9:dd:c25:c25:94de:ed4f
812c19:dd:d9:dd:c25:c25:94de:ed50/1282c19:dd:d9:dd:c25:c25:94de:ed50
822c19:dd:d9:dd:c25:c25:94de:ed51/1282c19:dd:d9:dd:c25:c25:94de:ed51
832c19:dd:d9:dd:c25:c25:94de:ed52/1282c19:dd:d9:dd:c25:c25:94de:ed52
842c19:dd:d9:dd:c25:c25:94de:ed53/1282c19:dd:d9:dd:c25:c25:94de:ed53
852c19:dd:d9:dd:c25:c25:94de:ed54/1282c19:dd:d9:dd:c25:c25:94de:ed54
862c19:dd:d9:dd:c25:c25:94de:ed55/1282c19:dd:d9:dd:c25:c25:94de:ed55
872c19:dd:d9:dd:c25:c25:94de:ed56/1282c19:dd:d9:dd:c25:c25:94de:ed56
882c19:dd:d9:dd:c25:c25:94de:ed57/1282c19:dd:d9:dd:c25:c25:94de:ed57
892c19:dd:d9:dd:c25:c25:94de:ed58/1282c19:dd:d9:dd:c25:c25:94de:ed58
902c19:dd:d9:dd:c25:c25:94de:ed59/1282c19:dd:d9:dd:c25:c25:94de:ed59
912c19:dd:d9:dd:c25:c25:94de:ed5a/1282c19:dd:d9:dd:c25:c25:94de:ed5a
922c19:dd:d9:dd:c25:c25:94de:ed5b/1282c19:dd:d9:dd:c25:c25:94de:ed5b
932c19:dd:d9:dd:c25:c25:94de:ed5c/1282c19:dd:d9:dd:c25:c25:94de:ed5c
942c19:dd:d9:dd:c25:c25:94de:ed5d/1282c19:dd:d9:dd:c25:c25:94de:ed5d
952c19:dd:d9:dd:c25:c25:94de:ed5e/1282c19:dd:d9:dd:c25:c25:94de:ed5e
962c19:dd:d9:dd:c25:c25:94de:ed5f/1282c19:dd:d9:dd:c25:c25:94de:ed5f
972c19:dd:d9:dd:c25:c25:94de:ed60/1282c19:dd:d9:dd:c25:c25:94de:ed60
982c19:dd:d9:dd:c25:c25:94de:ed61/1282c19:dd:d9:dd:c25:c25:94de:ed61
992c19:dd:d9:dd:c25:c25:94de:ed62/1282c19:dd:d9:dd:c25:c25:94de:ed62
1002c19:dd:d9:dd:c25:c25:94de:ed63/1282c19:dd:d9:dd:c25:c25:94de:ed63
1012c19:dd:d9:dd:c25:c25:94de:ed64/1282c19:dd:d9:dd:c25:c25:94de:ed64
1022c19:dd:d9:dd:c25:c25:94de:ed65/1282c19:dd:d9:dd:c25:c25:94de:ed65
1032c19:dd:d9:dd:c25:c25:94de:ed66/1282c19:dd:d9:dd:c25:c25:94de:ed66
1042c19:dd:d9:dd:c25:c25:94de:ed67/1282c19:dd:d9:dd:c25:c25:94de:ed67
1052c19:dd:d9:dd:c25:c25:94de:ed68/1282c19:dd:d9:dd:c25:c25:94de:ed68
1062c19:dd:d9:dd:c25:c25:94de:ed69/1282c19:dd:d9:dd:c25:c25:94de:ed69
1072c19:dd:d9:dd:c25:c25:94de:ed6a/1282c19:dd:d9:dd:c25:c25:94de:ed6a
1082c19:dd:d9:dd:c25:c25:94de:ed6b/1282c19:dd:d9:dd:c25:c25:94de:ed6b
1092c19:dd:d9:dd:c25:c25:94de:ed6c/1282c19:dd:d9:dd:c25:c25:94de:ed6c
1102c19:dd:d9:dd:c25:c25:94de:ed6d/1282c19:dd:d9:dd:c25:c25:94de:ed6d
1112c19:dd:d9:dd:c25:c25:94de:ed6e/1282c19:dd:d9:dd:c25:c25:94de:ed6e
1122c19:dd:d9:dd:c25:c25:94de:ed6f/1282c19:dd:d9:dd:c25:c25:94de:ed6f
1132c19:dd:d9:dd:c25:c25:94de:ed70/1282c19:dd:d9:dd:c25:c25:94de:ed70
1142c19:dd:d9:dd:c25:c25:94de:ed71/1282c19:dd:d9:dd:c25:c25:94de:ed71
1152c19:dd:d9:dd:c25:c25:94de:ed72/1282c19:dd:d9:dd:c25:c25:94de:ed72
1162c19:dd:d9:dd:c25:c25:94de:ed73/1282c19:dd:d9:dd:c25:c25:94de:ed73
1172c19:dd:d9:dd:c25:c25:94de:ed74/1282c19:dd:d9:dd:c25:c25:94de:ed74
1182c19:dd:d9:dd:c25:c25:94de:ed75/1282c19:dd:d9:dd:c25:c25:94de:ed75
1192c19:dd:d9:dd:c25:c25:94de:ed76/1282c19:dd:d9:dd:c25:c25:94de:ed76
1202c19:dd:d9:dd:c25:c25:94de:ed77/1282c19:dd:d9:dd:c25:c25:94de:ed77
1212c19:dd:d9:dd:c25:c25:94de:ed78/1282c19:dd:d9:dd:c25:c25:94de:ed78
1222c19:dd:d9:dd:c25:c25:94de:ed79/1282c19:dd:d9:dd:c25:c25:94de:ed79
1232c19:dd:d9:dd:c25:c25:94de:ed7a/1282c19:dd:d9:dd:c25:c25:94de:ed7a
1242c19:dd:d9:dd:c25:c25:94de:ed7b/1282c19:dd:d9:dd:c25:c25:94de:ed7b
1252c19:dd:d9:dd:c25:c25:94de:ed7c/1282c19:dd:d9:dd:c25:c25:94de:ed7c
1262c19:dd:d9:dd:c25:c25:94de:ed7d/1282c19:dd:d9:dd:c25:c25:94de:ed7d
1272c19:dd:d9:dd:c25:c25:94de:ed7e/1282c19:dd:d9:dd:c25:c25:94de:ed7e
1282c19:dd:d9:dd:c25:c25:94de:ed7f/1282c19:dd:d9:dd:c25:c25:94de:ed7f
1292c19:dd:d9:dd:c25:c25:94de:ed80/1282c19:dd:d9:dd:c25:c25:94de:ed80
1302c19:dd:d9:dd:c25:c25:94de:ed81/1282c19:dd:d9:dd:c25:c25:94de:ed81
1312c19:dd:d9:dd:c25:c25:94de:ed82/1282c19:dd:d9:dd:c25:c25:94de:ed82
1322c19:dd:d9:dd:c25:c25:94de:ed83/1282c19:dd:d9:dd:c25:c25:94de:ed83
1332c19:dd:d9:dd:c25:c25:94de:ed84/1282c19:dd:d9:dd:c25:c25:94de:ed84
1342c19:dd:d9:dd:c25:c25:94de:ed85/1282c19:dd:d9:dd:c25:c25:94de:ed85
1352c19:dd:d9:dd:c25:c25:94de:ed86/1282c19:dd:d9:dd:c25:c25:94de:ed86
1362c19:dd:d9:dd:c25:c25:94de:ed87/1282c19:dd:d9:dd:c25:c25:94de:ed87
1372c19:dd:d9:dd:c25:c25:94de:ed88/1282c19:dd:d9:dd:c25:c25:94de:ed88
1382c19:dd:d9:dd:c25:c25:94de:ed89/1282c19:dd:d9:dd:c25:c25:94de:ed89
1392c19:dd:d9:dd:c25:c25:94de:ed8a/1282c19:dd:d9:dd:c25:c25:94de:ed8a
1402c19:dd:d9:dd:c25:c25:94de:ed8b/1282c19:dd:d9:dd:c25:c25:94de:ed8b
1412c19:dd:d9:dd:c25:c25:94de:ed8c/1282c19:dd:d9:dd:c25:c25:94de:ed8c
1422c19:dd:d9:dd:c25:c25:94de:ed8d/1282c19:dd:d9:dd:c25:c25:94de:ed8d
1432c19:dd:d9:dd:c25:c25:94de:ed8e/1282c19:dd:d9:dd:c25:c25:94de:ed8e
1442c19:dd:d9:dd:c25:c25:94de:ed8f/1282c19:dd:d9:dd:c25:c25:94de:ed8f
1452c19:dd:d9:dd:c25:c25:94de:ed90/1282c19:dd:d9:dd:c25:c25:94de:ed90
1462c19:dd:d9:dd:c25:c25:94de:ed91/1282c19:dd:d9:dd:c25:c25:94de:ed91
1472c19:dd:d9:dd:c25:c25:94de:ed92/1282c19:dd:d9:dd:c25:c25:94de:ed92
1482c19:dd:d9:dd:c25:c25:94de:ed93/1282c19:dd:d9:dd:c25:c25:94de:ed93
1492c19:dd:d9:dd:c25:c25:94de:ed94/1282c19:dd:d9:dd:c25:c25:94de:ed94
1502c19:dd:d9:dd:c25:c25:94de:ed95/1282c19:dd:d9:dd:c25:c25:94de:ed95
1512c19:dd:d9:dd:c25:c25:94de:ed96/1282c19:dd:d9:dd:c25:c25:94de:ed96
1522c19:dd:d9:dd:c25:c25:94de:ed97/1282c19:dd:d9:dd:c25:c25:94de:ed97
1532c19:dd:d9:dd:c25:c25:94de:ed98/1282c19:dd:d9:dd:c25:c25:94de:ed98
1542c19:dd:d9:dd:c25:c25:94de:ed99/1282c19:dd:d9:dd:c25:c25:94de:ed99
1552c19:dd:d9:dd:c25:c25:94de:ed9a/1282c19:dd:d9:dd:c25:c25:94de:ed9a
1562c19:dd:d9:dd:c25:c25:94de:ed9b/1282c19:dd:d9:dd:c25:c25:94de:ed9b
1572c19:dd:d9:dd:c25:c25:94de:ed9c/1282c19:dd:d9:dd:c25:c25:94de:ed9c
1582c19:dd:d9:dd:c25:c25:94de:ed9d/1282c19:dd:d9:dd:c25:c25:94de:ed9d
1592c19:dd:d9:dd:c25:c25:94de:ed9e/1282c19:dd:d9:dd:c25:c25:94de:ed9e
1602c19:dd:d9:dd:c25:c25:94de:ed9f/1282c19:dd:d9:dd:c25:c25:94de:ed9f
1612c19:dd:d9:dd:c25:c25:94de:eda0/1282c19:dd:d9:dd:c25:c25:94de:eda0
1622c19:dd:d9:dd:c25:c25:94de:eda1/1282c19:dd:d9:dd:c25:c25:94de:eda1
1632c19:dd:d9:dd:c25:c25:94de:eda2/1282c19:dd:d9:dd:c25:c25:94de:eda2
1642c19:dd:d9:dd:c25:c25:94de:eda3/1282c19:dd:d9:dd:c25:c25:94de:eda3
1652c19:dd:d9:dd:c25:c25:94de:eda4/1282c19:dd:d9:dd:c25:c25:94de:eda4
1662c19:dd:d9:dd:c25:c25:94de:eda5/1282c19:dd:d9:dd:c25:c25:94de:eda5
1672c19:dd:d9:dd:c25:c25:94de:eda6/1282c19:dd:d9:dd:c25:c25:94de:eda6
1682c19:dd:d9:dd:c25:c25:94de:eda7/1282c19:dd:d9:dd:c25:c25:94de:eda7
1692c19:dd:d9:dd:c25:c25:94de:eda8/1282c19:dd:d9:dd:c25:c25:94de:eda8
1702c19:dd:d9:dd:c25:c25:94de:eda9/1282c19:dd:d9:dd:c25:c25:94de:eda9
1712c19:dd:d9:dd:c25:c25:94de:edaa/1282c19:dd:d9:dd:c25:c25:94de:edaa
1722c19:dd:d9:dd:c25:c25:94de:edab/1282c19:dd:d9:dd:c25:c25:94de:edab
1732c19:dd:d9:dd:c25:c25:94de:edac/1282c19:dd:d9:dd:c25:c25:94de:edac
1742c19:dd:d9:dd:c25:c25:94de:edad/1282c19:dd:d9:dd:c25:c25:94de:edad
1752c19:dd:d9:dd:c25:c25:94de:edae/1282c19:dd:d9:dd:c25:c25:94de:edae
1762c19:dd:d9:dd:c25:c25:94de:edaf/1282c19:dd:d9:dd:c25:c25:94de:edaf
1772c19:dd:d9:dd:c25:c25:94de:edb0/1282c19:dd:d9:dd:c25:c25:94de:edb0
1782c19:dd:d9:dd:c25:c25:94de:edb1/1282c19:dd:d9:dd:c25:c25:94de:edb1
1792c19:dd:d9:dd:c25:c25:94de:edb2/1282c19:dd:d9:dd:c25:c25:94de:edb2
1802c19:dd:d9:dd:c25:c25:94de:edb3/1282c19:dd:d9:dd:c25:c25:94de:edb3
1812c19:dd:d9:dd:c25:c25:94de:edb4/1282c19:dd:d9:dd:c25:c25:94de:edb4
1822c19:dd:d9:dd:c25:c25:94de:edb5/1282c19:dd:d9:dd:c25:c25:94de:edb5
1832c19:dd:d9:dd:c25:c25:94de:edb6/1282c19:dd:d9:dd:c25:c25:94de:edb6
1842c19:dd:d9:dd:c25:c25:94de:edb7/1282c19:dd:d9:dd:c25:c25:94de:edb7
1852c19:dd:d9:dd:c25:c25:94de:edb8/1282c19:dd:d9:dd:c25:c25:94de:edb8
1862c19:dd:d9:dd:c25:c25:94de:edb9/1282c19:dd:d9:dd:c25:c25:94de:edb9
1872c19:dd:d9:dd:c25:c25:94de:edba/1282c19:dd:d9:dd:c25:c25:94de:edba
1882c19:dd:d9:dd:c25:c25:94de:edbb/1282c19:dd:d9:dd:c25:c25:94de:edbb
1892c19:dd:d9:dd:c25:c25:94de:edbc/1282c19:dd:d9:dd:c25:c25:94de:edbc
1902c19:dd:d9:dd:c25:c25:94de:edbd/1282c19:dd:d9:dd:c25:c25:94de:edbd
1912c19:dd:d9:dd:c25:c25:94de:edbe/1282c19:dd:d9:dd:c25:c25:94de:edbe
1922c19:dd:d9:dd:c25:c25:94de:edbf/1282c19:dd:d9:dd:c25:c25:94de:edbf
1932c19:dd:d9:dd:c25:c25:94de:edc0/1282c19:dd:d9:dd:c25:c25:94de:edc0
1942c19:dd:d9:dd:c25:c25:94de:edc1/1282c19:dd:d9:dd:c25:c25:94de:edc1
1952c19:dd:d9:dd:c25:c25:94de:edc2/1282c19:dd:d9:dd:c25:c25:94de:edc2
1962c19:dd:d9:dd:c25:c25:94de:edc3/1282c19:dd:d9:dd:c25:c25:94de:edc3
1972c19:dd:d9:dd:c25:c25:94de:edc4/1282c19:dd:d9:dd:c25:c25:94de:edc4
1982c19:dd:d9:dd:c25:c25:94de:edc5/1282c19:dd:d9:dd:c25:c25:94de:edc5
1992c19:dd:d9:dd:c25:c25:94de:edc6/1282c19:dd:d9:dd:c25:c25:94de:edc6
2002c19:dd:d9:dd:c25:c25:94de:edc7/1282c19:dd:d9:dd:c25:c25:94de:edc7
2012c19:dd:d9:dd:c25:c25:94de:edc8/1282c19:dd:d9:dd:c25:c25:94de:edc8
2022c19:dd:d9:dd:c25:c25:94de:edc9/1282c19:dd:d9:dd:c25:c25:94de:edc9
2032c19:dd:d9:dd:c25:c25:94de:edca/1282c19:dd:d9:dd:c25:c25:94de:edca
2042c19:dd:d9:dd:c25:c25:94de:edcb/1282c19:dd:d9:dd:c25:c25:94de:edcb
2052c19:dd:d9:dd:c25:c25:94de:edcc/1282c19:dd:d9:dd:c25:c25:94de:edcc
2062c19:dd:d9:dd:c25:c25:94de:edcd/1282c19:dd:d9:dd:c25:c25:94de:edcd
2072c19:dd:d9:dd:c25:c25:94de:edce/1282c19:dd:d9:dd:c25:c25:94de:edce
2082c19:dd:d9:dd:c25:c25:94de:edcf/1282c19:dd:d9:dd:c25:c25:94de:edcf
2092c19:dd:d9:dd:c25:c25:94de:edd0/1282c19:dd:d9:dd:c25:c25:94de:edd0
2102c19:dd:d9:dd:c25:c25:94de:edd1/1282c19:dd:d9:dd:c25:c25:94de:edd1
2112c19:dd:d9:dd:c25:c25:94de:edd2/1282c19:dd:d9:dd:c25:c25:94de:edd2
2122c19:dd:d9:dd:c25:c25:94de:edd3/1282c19:dd:d9:dd:c25:c25:94de:edd3
2132c19:dd:d9:dd:c25:c25:94de:edd4/1282c19:dd:d9:dd:c25:c25:94de:edd4
2142c19:dd:d9:dd:c25:c25:94de:edd5/1282c19:dd:d9:dd:c25:c25:94de:edd5
2152c19:dd:d9:dd:c25:c25:94de:edd6/1282c19:dd:d9:dd:c25:c25:94de:edd6
2162c19:dd:d9:dd:c25:c25:94de:edd7/1282c19:dd:d9:dd:c25:c25:94de:edd7
2172c19:dd:d9:dd:c25:c25:94de:edd8/1282c19:dd:d9:dd:c25:c25:94de:edd8
2182c19:dd:d9:dd:c25:c25:94de:edd9/1282c19:dd:d9:dd:c25:c25:94de:edd9
2192c19:dd:d9:dd:c25:c25:94de:edda/1282c19:dd:d9:dd:c25:c25:94de:edda
2202c19:dd:d9:dd:c25:c25:94de:eddb/1282c19:dd:d9:dd:c25:c25:94de:eddb
2212c19:dd:d9:dd:c25:c25:94de:eddc/1282c19:dd:d9:dd:c25:c25:94de:eddc
2222c19:dd:d9:dd:c25:c25:94de:eddd/1282c19:dd:d9:dd:c25:c25:94de:eddd
2232c19:dd:d9:dd:c25:c25:94de:edde/1282c19:dd:d9:dd:c25:c25:94de:edde
2242c19:dd:d9:dd:c25:c25:94de:eddf/1282c19:dd:d9:dd:c25:c25:94de:eddf
2252c19:dd:d9:dd:c25:c25:94de:ede0/1282c19:dd:d9:dd:c25:c25:94de:ede0
2262c19:dd:d9:dd:c25:c25:94de:ede1/1282c19:dd:d9:dd:c25:c25:94de:ede1
2272c19:dd:d9:dd:c25:c25:94de:ede2/1282c19:dd:d9:dd:c25:c25:94de:ede2
2282c19:dd:d9:dd:c25:c25:94de:ede3/1282c19:dd:d9:dd:c25:c25:94de:ede3
2292c19:dd:d9:dd:c25:c25:94de:ede4/1282c19:dd:d9:dd:c25:c25:94de:ede4
2302c19:dd:d9:dd:c25:c25:94de:ede5/1282c19:dd:d9:dd:c25:c25:94de:ede5
2312c19:dd:d9:dd:c25:c25:94de:ede6/1282c19:dd:d9:dd:c25:c25:94de:ede6
2322c19:dd:d9:dd:c25:c25:94de:ede7/1282c19:dd:d9:dd:c25:c25:94de:ede7
2332c19:dd:d9:dd:c25:c25:94de:ede8/1282c19:dd:d9:dd:c25:c25:94de:ede8
2342c19:dd:d9:dd:c25:c25:94de:ede9/1282c19:dd:d9:dd:c25:c25:94de:ede9
2352c19:dd:d9:dd:c25:c25:94de:edea/1282c19:dd:d9:dd:c25:c25:94de:edea
2362c19:dd:d9:dd:c25:c25:94de:edeb/1282c19:dd:d9:dd:c25:c25:94de:edeb
2372c19:dd:d9:dd:c25:c25:94de:edec/1282c19:dd:d9:dd:c25:c25:94de:edec
2382c19:dd:d9:dd:c25:c25:94de:eded/1282c19:dd:d9:dd:c25:c25:94de:eded
2392c19:dd:d9:dd:c25:c25:94de:edee/1282c19:dd:d9:dd:c25:c25:94de:edee
2402c19:dd:d9:dd:c25:c25:94de:edef/1282c19:dd:d9:dd:c25:c25:94de:edef
2412c19:dd:d9:dd:c25:c25:94de:edf0/1282c19:dd:d9:dd:c25:c25:94de:edf0
2422c19:dd:d9:dd:c25:c25:94de:edf1/1282c19:dd:d9:dd:c25:c25:94de:edf1
2432c19:dd:d9:dd:c25:c25:94de:edf2/1282c19:dd:d9:dd:c25:c25:94de:edf2
2442c19:dd:d9:dd:c25:c25:94de:edf3/1282c19:dd:d9:dd:c25:c25:94de:edf3
2452c19:dd:d9:dd:c25:c25:94de:edf4/1282c19:dd:d9:dd:c25:c25:94de:edf4
2462c19:dd:d9:dd:c25:c25:94de:edf5/1282c19:dd:d9:dd:c25:c25:94de:edf5
2472c19:dd:d9:dd:c25:c25:94de:edf6/1282c19:dd:d9:dd:c25:c25:94de:edf6
2482c19:dd:d9:dd:c25:c25:94de:edf7/1282c19:dd:d9:dd:c25:c25:94de:edf7
2492c19:dd:d9:dd:c25:c25:94de:edf8/1282c19:dd:d9:dd:c25:c25:94de:edf8
2502c19:dd:d9:dd:c25:c25:94de:edf9/1282c19:dd:d9:dd:c25:c25:94de:edf9
2512c19:dd:d9:dd:c25:c25:94de:edfa/1282c19:dd:d9:dd:c25:c25:94de:edfa
2522c19:dd:d9:dd:c25:c25:94de:edfb/1282c19:dd:d9:dd:c25:c25:94de:edfb
2532c19:dd:d9:dd:c25:c25:94de:edfc/1282c19:dd:d9:dd:c25:c25:94de:edfc
2542c19:dd:d9:dd:c25:c25:94de:edfd/1282c19:dd:d9:dd:c25:c25:94de:edfd
2552c19:dd:d9:dd:c25:c25:94de:edfe/1282c19:dd:d9:dd:c25:c25:94de:edfe
2562c19:dd:d9:dd:c25:c25:94de:edff/1282c19:dd:d9:dd:c25:c25:94de:edff

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.