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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:d915:bc00/120
First address
2c19:dd:d9:dd:c25:c25:d915:bc00
Last address
2c19:dd:d9:dd:c25:c25:d915:bcff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:bc00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
c.b.5.1.9.d.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:d915:bc00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:bc00/1282c19:dd:d9:dd:c25:c25:d915:bc00
22c19:dd:d9:dd:c25:c25:d915:bc01/1282c19:dd:d9:dd:c25:c25:d915:bc01
32c19:dd:d9:dd:c25:c25:d915:bc02/1282c19:dd:d9:dd:c25:c25:d915:bc02
42c19:dd:d9:dd:c25:c25:d915:bc03/1282c19:dd:d9:dd:c25:c25:d915:bc03
52c19:dd:d9:dd:c25:c25:d915:bc04/1282c19:dd:d9:dd:c25:c25:d915:bc04
62c19:dd:d9:dd:c25:c25:d915:bc05/1282c19:dd:d9:dd:c25:c25:d915:bc05
72c19:dd:d9:dd:c25:c25:d915:bc06/1282c19:dd:d9:dd:c25:c25:d915:bc06
82c19:dd:d9:dd:c25:c25:d915:bc07/1282c19:dd:d9:dd:c25:c25:d915:bc07
92c19:dd:d9:dd:c25:c25:d915:bc08/1282c19:dd:d9:dd:c25:c25:d915:bc08
102c19:dd:d9:dd:c25:c25:d915:bc09/1282c19:dd:d9:dd:c25:c25:d915:bc09
112c19:dd:d9:dd:c25:c25:d915:bc0a/1282c19:dd:d9:dd:c25:c25:d915:bc0a
122c19:dd:d9:dd:c25:c25:d915:bc0b/1282c19:dd:d9:dd:c25:c25:d915:bc0b
132c19:dd:d9:dd:c25:c25:d915:bc0c/1282c19:dd:d9:dd:c25:c25:d915:bc0c
142c19:dd:d9:dd:c25:c25:d915:bc0d/1282c19:dd:d9:dd:c25:c25:d915:bc0d
152c19:dd:d9:dd:c25:c25:d915:bc0e/1282c19:dd:d9:dd:c25:c25:d915:bc0e
162c19:dd:d9:dd:c25:c25:d915:bc0f/1282c19:dd:d9:dd:c25:c25:d915:bc0f
172c19:dd:d9:dd:c25:c25:d915:bc10/1282c19:dd:d9:dd:c25:c25:d915:bc10
182c19:dd:d9:dd:c25:c25:d915:bc11/1282c19:dd:d9:dd:c25:c25:d915:bc11
192c19:dd:d9:dd:c25:c25:d915:bc12/1282c19:dd:d9:dd:c25:c25:d915:bc12
202c19:dd:d9:dd:c25:c25:d915:bc13/1282c19:dd:d9:dd:c25:c25:d915:bc13
212c19:dd:d9:dd:c25:c25:d915:bc14/1282c19:dd:d9:dd:c25:c25:d915:bc14
222c19:dd:d9:dd:c25:c25:d915:bc15/1282c19:dd:d9:dd:c25:c25:d915:bc15
232c19:dd:d9:dd:c25:c25:d915:bc16/1282c19:dd:d9:dd:c25:c25:d915:bc16
242c19:dd:d9:dd:c25:c25:d915:bc17/1282c19:dd:d9:dd:c25:c25:d915:bc17
252c19:dd:d9:dd:c25:c25:d915:bc18/1282c19:dd:d9:dd:c25:c25:d915:bc18
262c19:dd:d9:dd:c25:c25:d915:bc19/1282c19:dd:d9:dd:c25:c25:d915:bc19
272c19:dd:d9:dd:c25:c25:d915:bc1a/1282c19:dd:d9:dd:c25:c25:d915:bc1a
282c19:dd:d9:dd:c25:c25:d915:bc1b/1282c19:dd:d9:dd:c25:c25:d915:bc1b
292c19:dd:d9:dd:c25:c25:d915:bc1c/1282c19:dd:d9:dd:c25:c25:d915:bc1c
302c19:dd:d9:dd:c25:c25:d915:bc1d/1282c19:dd:d9:dd:c25:c25:d915:bc1d
312c19:dd:d9:dd:c25:c25:d915:bc1e/1282c19:dd:d9:dd:c25:c25:d915:bc1e
322c19:dd:d9:dd:c25:c25:d915:bc1f/1282c19:dd:d9:dd:c25:c25:d915:bc1f
332c19:dd:d9:dd:c25:c25:d915:bc20/1282c19:dd:d9:dd:c25:c25:d915:bc20
342c19:dd:d9:dd:c25:c25:d915:bc21/1282c19:dd:d9:dd:c25:c25:d915:bc21
352c19:dd:d9:dd:c25:c25:d915:bc22/1282c19:dd:d9:dd:c25:c25:d915:bc22
362c19:dd:d9:dd:c25:c25:d915:bc23/1282c19:dd:d9:dd:c25:c25:d915:bc23
372c19:dd:d9:dd:c25:c25:d915:bc24/1282c19:dd:d9:dd:c25:c25:d915:bc24
382c19:dd:d9:dd:c25:c25:d915:bc25/1282c19:dd:d9:dd:c25:c25:d915:bc25
392c19:dd:d9:dd:c25:c25:d915:bc26/1282c19:dd:d9:dd:c25:c25:d915:bc26
402c19:dd:d9:dd:c25:c25:d915:bc27/1282c19:dd:d9:dd:c25:c25:d915:bc27
412c19:dd:d9:dd:c25:c25:d915:bc28/1282c19:dd:d9:dd:c25:c25:d915:bc28
422c19:dd:d9:dd:c25:c25:d915:bc29/1282c19:dd:d9:dd:c25:c25:d915:bc29
432c19:dd:d9:dd:c25:c25:d915:bc2a/1282c19:dd:d9:dd:c25:c25:d915:bc2a
442c19:dd:d9:dd:c25:c25:d915:bc2b/1282c19:dd:d9:dd:c25:c25:d915:bc2b
452c19:dd:d9:dd:c25:c25:d915:bc2c/1282c19:dd:d9:dd:c25:c25:d915:bc2c
462c19:dd:d9:dd:c25:c25:d915:bc2d/1282c19:dd:d9:dd:c25:c25:d915:bc2d
472c19:dd:d9:dd:c25:c25:d915:bc2e/1282c19:dd:d9:dd:c25:c25:d915:bc2e
482c19:dd:d9:dd:c25:c25:d915:bc2f/1282c19:dd:d9:dd:c25:c25:d915:bc2f
492c19:dd:d9:dd:c25:c25:d915:bc30/1282c19:dd:d9:dd:c25:c25:d915:bc30
502c19:dd:d9:dd:c25:c25:d915:bc31/1282c19:dd:d9:dd:c25:c25:d915:bc31
512c19:dd:d9:dd:c25:c25:d915:bc32/1282c19:dd:d9:dd:c25:c25:d915:bc32
522c19:dd:d9:dd:c25:c25:d915:bc33/1282c19:dd:d9:dd:c25:c25:d915:bc33
532c19:dd:d9:dd:c25:c25:d915:bc34/1282c19:dd:d9:dd:c25:c25:d915:bc34
542c19:dd:d9:dd:c25:c25:d915:bc35/1282c19:dd:d9:dd:c25:c25:d915:bc35
552c19:dd:d9:dd:c25:c25:d915:bc36/1282c19:dd:d9:dd:c25:c25:d915:bc36
562c19:dd:d9:dd:c25:c25:d915:bc37/1282c19:dd:d9:dd:c25:c25:d915:bc37
572c19:dd:d9:dd:c25:c25:d915:bc38/1282c19:dd:d9:dd:c25:c25:d915:bc38
582c19:dd:d9:dd:c25:c25:d915:bc39/1282c19:dd:d9:dd:c25:c25:d915:bc39
592c19:dd:d9:dd:c25:c25:d915:bc3a/1282c19:dd:d9:dd:c25:c25:d915:bc3a
602c19:dd:d9:dd:c25:c25:d915:bc3b/1282c19:dd:d9:dd:c25:c25:d915:bc3b
612c19:dd:d9:dd:c25:c25:d915:bc3c/1282c19:dd:d9:dd:c25:c25:d915:bc3c
622c19:dd:d9:dd:c25:c25:d915:bc3d/1282c19:dd:d9:dd:c25:c25:d915:bc3d
632c19:dd:d9:dd:c25:c25:d915:bc3e/1282c19:dd:d9:dd:c25:c25:d915:bc3e
642c19:dd:d9:dd:c25:c25:d915:bc3f/1282c19:dd:d9:dd:c25:c25:d915:bc3f
652c19:dd:d9:dd:c25:c25:d915:bc40/1282c19:dd:d9:dd:c25:c25:d915:bc40
662c19:dd:d9:dd:c25:c25:d915:bc41/1282c19:dd:d9:dd:c25:c25:d915:bc41
672c19:dd:d9:dd:c25:c25:d915:bc42/1282c19:dd:d9:dd:c25:c25:d915:bc42
682c19:dd:d9:dd:c25:c25:d915:bc43/1282c19:dd:d9:dd:c25:c25:d915:bc43
692c19:dd:d9:dd:c25:c25:d915:bc44/1282c19:dd:d9:dd:c25:c25:d915:bc44
702c19:dd:d9:dd:c25:c25:d915:bc45/1282c19:dd:d9:dd:c25:c25:d915:bc45
712c19:dd:d9:dd:c25:c25:d915:bc46/1282c19:dd:d9:dd:c25:c25:d915:bc46
722c19:dd:d9:dd:c25:c25:d915:bc47/1282c19:dd:d9:dd:c25:c25:d915:bc47
732c19:dd:d9:dd:c25:c25:d915:bc48/1282c19:dd:d9:dd:c25:c25:d915:bc48
742c19:dd:d9:dd:c25:c25:d915:bc49/1282c19:dd:d9:dd:c25:c25:d915:bc49
752c19:dd:d9:dd:c25:c25:d915:bc4a/1282c19:dd:d9:dd:c25:c25:d915:bc4a
762c19:dd:d9:dd:c25:c25:d915:bc4b/1282c19:dd:d9:dd:c25:c25:d915:bc4b
772c19:dd:d9:dd:c25:c25:d915:bc4c/1282c19:dd:d9:dd:c25:c25:d915:bc4c
782c19:dd:d9:dd:c25:c25:d915:bc4d/1282c19:dd:d9:dd:c25:c25:d915:bc4d
792c19:dd:d9:dd:c25:c25:d915:bc4e/1282c19:dd:d9:dd:c25:c25:d915:bc4e
802c19:dd:d9:dd:c25:c25:d915:bc4f/1282c19:dd:d9:dd:c25:c25:d915:bc4f
812c19:dd:d9:dd:c25:c25:d915:bc50/1282c19:dd:d9:dd:c25:c25:d915:bc50
822c19:dd:d9:dd:c25:c25:d915:bc51/1282c19:dd:d9:dd:c25:c25:d915:bc51
832c19:dd:d9:dd:c25:c25:d915:bc52/1282c19:dd:d9:dd:c25:c25:d915:bc52
842c19:dd:d9:dd:c25:c25:d915:bc53/1282c19:dd:d9:dd:c25:c25:d915:bc53
852c19:dd:d9:dd:c25:c25:d915:bc54/1282c19:dd:d9:dd:c25:c25:d915:bc54
862c19:dd:d9:dd:c25:c25:d915:bc55/1282c19:dd:d9:dd:c25:c25:d915:bc55
872c19:dd:d9:dd:c25:c25:d915:bc56/1282c19:dd:d9:dd:c25:c25:d915:bc56
882c19:dd:d9:dd:c25:c25:d915:bc57/1282c19:dd:d9:dd:c25:c25:d915:bc57
892c19:dd:d9:dd:c25:c25:d915:bc58/1282c19:dd:d9:dd:c25:c25:d915:bc58
902c19:dd:d9:dd:c25:c25:d915:bc59/1282c19:dd:d9:dd:c25:c25:d915:bc59
912c19:dd:d9:dd:c25:c25:d915:bc5a/1282c19:dd:d9:dd:c25:c25:d915:bc5a
922c19:dd:d9:dd:c25:c25:d915:bc5b/1282c19:dd:d9:dd:c25:c25:d915:bc5b
932c19:dd:d9:dd:c25:c25:d915:bc5c/1282c19:dd:d9:dd:c25:c25:d915:bc5c
942c19:dd:d9:dd:c25:c25:d915:bc5d/1282c19:dd:d9:dd:c25:c25:d915:bc5d
952c19:dd:d9:dd:c25:c25:d915:bc5e/1282c19:dd:d9:dd:c25:c25:d915:bc5e
962c19:dd:d9:dd:c25:c25:d915:bc5f/1282c19:dd:d9:dd:c25:c25:d915:bc5f
972c19:dd:d9:dd:c25:c25:d915:bc60/1282c19:dd:d9:dd:c25:c25:d915:bc60
982c19:dd:d9:dd:c25:c25:d915:bc61/1282c19:dd:d9:dd:c25:c25:d915:bc61
992c19:dd:d9:dd:c25:c25:d915:bc62/1282c19:dd:d9:dd:c25:c25:d915:bc62
1002c19:dd:d9:dd:c25:c25:d915:bc63/1282c19:dd:d9:dd:c25:c25:d915:bc63
1012c19:dd:d9:dd:c25:c25:d915:bc64/1282c19:dd:d9:dd:c25:c25:d915:bc64
1022c19:dd:d9:dd:c25:c25:d915:bc65/1282c19:dd:d9:dd:c25:c25:d915:bc65
1032c19:dd:d9:dd:c25:c25:d915:bc66/1282c19:dd:d9:dd:c25:c25:d915:bc66
1042c19:dd:d9:dd:c25:c25:d915:bc67/1282c19:dd:d9:dd:c25:c25:d915:bc67
1052c19:dd:d9:dd:c25:c25:d915:bc68/1282c19:dd:d9:dd:c25:c25:d915:bc68
1062c19:dd:d9:dd:c25:c25:d915:bc69/1282c19:dd:d9:dd:c25:c25:d915:bc69
1072c19:dd:d9:dd:c25:c25:d915:bc6a/1282c19:dd:d9:dd:c25:c25:d915:bc6a
1082c19:dd:d9:dd:c25:c25:d915:bc6b/1282c19:dd:d9:dd:c25:c25:d915:bc6b
1092c19:dd:d9:dd:c25:c25:d915:bc6c/1282c19:dd:d9:dd:c25:c25:d915:bc6c
1102c19:dd:d9:dd:c25:c25:d915:bc6d/1282c19:dd:d9:dd:c25:c25:d915:bc6d
1112c19:dd:d9:dd:c25:c25:d915:bc6e/1282c19:dd:d9:dd:c25:c25:d915:bc6e
1122c19:dd:d9:dd:c25:c25:d915:bc6f/1282c19:dd:d9:dd:c25:c25:d915:bc6f
1132c19:dd:d9:dd:c25:c25:d915:bc70/1282c19:dd:d9:dd:c25:c25:d915:bc70
1142c19:dd:d9:dd:c25:c25:d915:bc71/1282c19:dd:d9:dd:c25:c25:d915:bc71
1152c19:dd:d9:dd:c25:c25:d915:bc72/1282c19:dd:d9:dd:c25:c25:d915:bc72
1162c19:dd:d9:dd:c25:c25:d915:bc73/1282c19:dd:d9:dd:c25:c25:d915:bc73
1172c19:dd:d9:dd:c25:c25:d915:bc74/1282c19:dd:d9:dd:c25:c25:d915:bc74
1182c19:dd:d9:dd:c25:c25:d915:bc75/1282c19:dd:d9:dd:c25:c25:d915:bc75
1192c19:dd:d9:dd:c25:c25:d915:bc76/1282c19:dd:d9:dd:c25:c25:d915:bc76
1202c19:dd:d9:dd:c25:c25:d915:bc77/1282c19:dd:d9:dd:c25:c25:d915:bc77
1212c19:dd:d9:dd:c25:c25:d915:bc78/1282c19:dd:d9:dd:c25:c25:d915:bc78
1222c19:dd:d9:dd:c25:c25:d915:bc79/1282c19:dd:d9:dd:c25:c25:d915:bc79
1232c19:dd:d9:dd:c25:c25:d915:bc7a/1282c19:dd:d9:dd:c25:c25:d915:bc7a
1242c19:dd:d9:dd:c25:c25:d915:bc7b/1282c19:dd:d9:dd:c25:c25:d915:bc7b
1252c19:dd:d9:dd:c25:c25:d915:bc7c/1282c19:dd:d9:dd:c25:c25:d915:bc7c
1262c19:dd:d9:dd:c25:c25:d915:bc7d/1282c19:dd:d9:dd:c25:c25:d915:bc7d
1272c19:dd:d9:dd:c25:c25:d915:bc7e/1282c19:dd:d9:dd:c25:c25:d915:bc7e
1282c19:dd:d9:dd:c25:c25:d915:bc7f/1282c19:dd:d9:dd:c25:c25:d915:bc7f
1292c19:dd:d9:dd:c25:c25:d915:bc80/1282c19:dd:d9:dd:c25:c25:d915:bc80
1302c19:dd:d9:dd:c25:c25:d915:bc81/1282c19:dd:d9:dd:c25:c25:d915:bc81
1312c19:dd:d9:dd:c25:c25:d915:bc82/1282c19:dd:d9:dd:c25:c25:d915:bc82
1322c19:dd:d9:dd:c25:c25:d915:bc83/1282c19:dd:d9:dd:c25:c25:d915:bc83
1332c19:dd:d9:dd:c25:c25:d915:bc84/1282c19:dd:d9:dd:c25:c25:d915:bc84
1342c19:dd:d9:dd:c25:c25:d915:bc85/1282c19:dd:d9:dd:c25:c25:d915:bc85
1352c19:dd:d9:dd:c25:c25:d915:bc86/1282c19:dd:d9:dd:c25:c25:d915:bc86
1362c19:dd:d9:dd:c25:c25:d915:bc87/1282c19:dd:d9:dd:c25:c25:d915:bc87
1372c19:dd:d9:dd:c25:c25:d915:bc88/1282c19:dd:d9:dd:c25:c25:d915:bc88
1382c19:dd:d9:dd:c25:c25:d915:bc89/1282c19:dd:d9:dd:c25:c25:d915:bc89
1392c19:dd:d9:dd:c25:c25:d915:bc8a/1282c19:dd:d9:dd:c25:c25:d915:bc8a
1402c19:dd:d9:dd:c25:c25:d915:bc8b/1282c19:dd:d9:dd:c25:c25:d915:bc8b
1412c19:dd:d9:dd:c25:c25:d915:bc8c/1282c19:dd:d9:dd:c25:c25:d915:bc8c
1422c19:dd:d9:dd:c25:c25:d915:bc8d/1282c19:dd:d9:dd:c25:c25:d915:bc8d
1432c19:dd:d9:dd:c25:c25:d915:bc8e/1282c19:dd:d9:dd:c25:c25:d915:bc8e
1442c19:dd:d9:dd:c25:c25:d915:bc8f/1282c19:dd:d9:dd:c25:c25:d915:bc8f
1452c19:dd:d9:dd:c25:c25:d915:bc90/1282c19:dd:d9:dd:c25:c25:d915:bc90
1462c19:dd:d9:dd:c25:c25:d915:bc91/1282c19:dd:d9:dd:c25:c25:d915:bc91
1472c19:dd:d9:dd:c25:c25:d915:bc92/1282c19:dd:d9:dd:c25:c25:d915:bc92
1482c19:dd:d9:dd:c25:c25:d915:bc93/1282c19:dd:d9:dd:c25:c25:d915:bc93
1492c19:dd:d9:dd:c25:c25:d915:bc94/1282c19:dd:d9:dd:c25:c25:d915:bc94
1502c19:dd:d9:dd:c25:c25:d915:bc95/1282c19:dd:d9:dd:c25:c25:d915:bc95
1512c19:dd:d9:dd:c25:c25:d915:bc96/1282c19:dd:d9:dd:c25:c25:d915:bc96
1522c19:dd:d9:dd:c25:c25:d915:bc97/1282c19:dd:d9:dd:c25:c25:d915:bc97
1532c19:dd:d9:dd:c25:c25:d915:bc98/1282c19:dd:d9:dd:c25:c25:d915:bc98
1542c19:dd:d9:dd:c25:c25:d915:bc99/1282c19:dd:d9:dd:c25:c25:d915:bc99
1552c19:dd:d9:dd:c25:c25:d915:bc9a/1282c19:dd:d9:dd:c25:c25:d915:bc9a
1562c19:dd:d9:dd:c25:c25:d915:bc9b/1282c19:dd:d9:dd:c25:c25:d915:bc9b
1572c19:dd:d9:dd:c25:c25:d915:bc9c/1282c19:dd:d9:dd:c25:c25:d915:bc9c
1582c19:dd:d9:dd:c25:c25:d915:bc9d/1282c19:dd:d9:dd:c25:c25:d915:bc9d
1592c19:dd:d9:dd:c25:c25:d915:bc9e/1282c19:dd:d9:dd:c25:c25:d915:bc9e
1602c19:dd:d9:dd:c25:c25:d915:bc9f/1282c19:dd:d9:dd:c25:c25:d915:bc9f
1612c19:dd:d9:dd:c25:c25:d915:bca0/1282c19:dd:d9:dd:c25:c25:d915:bca0
1622c19:dd:d9:dd:c25:c25:d915:bca1/1282c19:dd:d9:dd:c25:c25:d915:bca1
1632c19:dd:d9:dd:c25:c25:d915:bca2/1282c19:dd:d9:dd:c25:c25:d915:bca2
1642c19:dd:d9:dd:c25:c25:d915:bca3/1282c19:dd:d9:dd:c25:c25:d915:bca3
1652c19:dd:d9:dd:c25:c25:d915:bca4/1282c19:dd:d9:dd:c25:c25:d915:bca4
1662c19:dd:d9:dd:c25:c25:d915:bca5/1282c19:dd:d9:dd:c25:c25:d915:bca5
1672c19:dd:d9:dd:c25:c25:d915:bca6/1282c19:dd:d9:dd:c25:c25:d915:bca6
1682c19:dd:d9:dd:c25:c25:d915:bca7/1282c19:dd:d9:dd:c25:c25:d915:bca7
1692c19:dd:d9:dd:c25:c25:d915:bca8/1282c19:dd:d9:dd:c25:c25:d915:bca8
1702c19:dd:d9:dd:c25:c25:d915:bca9/1282c19:dd:d9:dd:c25:c25:d915:bca9
1712c19:dd:d9:dd:c25:c25:d915:bcaa/1282c19:dd:d9:dd:c25:c25:d915:bcaa
1722c19:dd:d9:dd:c25:c25:d915:bcab/1282c19:dd:d9:dd:c25:c25:d915:bcab
1732c19:dd:d9:dd:c25:c25:d915:bcac/1282c19:dd:d9:dd:c25:c25:d915:bcac
1742c19:dd:d9:dd:c25:c25:d915:bcad/1282c19:dd:d9:dd:c25:c25:d915:bcad
1752c19:dd:d9:dd:c25:c25:d915:bcae/1282c19:dd:d9:dd:c25:c25:d915:bcae
1762c19:dd:d9:dd:c25:c25:d915:bcaf/1282c19:dd:d9:dd:c25:c25:d915:bcaf
1772c19:dd:d9:dd:c25:c25:d915:bcb0/1282c19:dd:d9:dd:c25:c25:d915:bcb0
1782c19:dd:d9:dd:c25:c25:d915:bcb1/1282c19:dd:d9:dd:c25:c25:d915:bcb1
1792c19:dd:d9:dd:c25:c25:d915:bcb2/1282c19:dd:d9:dd:c25:c25:d915:bcb2
1802c19:dd:d9:dd:c25:c25:d915:bcb3/1282c19:dd:d9:dd:c25:c25:d915:bcb3
1812c19:dd:d9:dd:c25:c25:d915:bcb4/1282c19:dd:d9:dd:c25:c25:d915:bcb4
1822c19:dd:d9:dd:c25:c25:d915:bcb5/1282c19:dd:d9:dd:c25:c25:d915:bcb5
1832c19:dd:d9:dd:c25:c25:d915:bcb6/1282c19:dd:d9:dd:c25:c25:d915:bcb6
1842c19:dd:d9:dd:c25:c25:d915:bcb7/1282c19:dd:d9:dd:c25:c25:d915:bcb7
1852c19:dd:d9:dd:c25:c25:d915:bcb8/1282c19:dd:d9:dd:c25:c25:d915:bcb8
1862c19:dd:d9:dd:c25:c25:d915:bcb9/1282c19:dd:d9:dd:c25:c25:d915:bcb9
1872c19:dd:d9:dd:c25:c25:d915:bcba/1282c19:dd:d9:dd:c25:c25:d915:bcba
1882c19:dd:d9:dd:c25:c25:d915:bcbb/1282c19:dd:d9:dd:c25:c25:d915:bcbb
1892c19:dd:d9:dd:c25:c25:d915:bcbc/1282c19:dd:d9:dd:c25:c25:d915:bcbc
1902c19:dd:d9:dd:c25:c25:d915:bcbd/1282c19:dd:d9:dd:c25:c25:d915:bcbd
1912c19:dd:d9:dd:c25:c25:d915:bcbe/1282c19:dd:d9:dd:c25:c25:d915:bcbe
1922c19:dd:d9:dd:c25:c25:d915:bcbf/1282c19:dd:d9:dd:c25:c25:d915:bcbf
1932c19:dd:d9:dd:c25:c25:d915:bcc0/1282c19:dd:d9:dd:c25:c25:d915:bcc0
1942c19:dd:d9:dd:c25:c25:d915:bcc1/1282c19:dd:d9:dd:c25:c25:d915:bcc1
1952c19:dd:d9:dd:c25:c25:d915:bcc2/1282c19:dd:d9:dd:c25:c25:d915:bcc2
1962c19:dd:d9:dd:c25:c25:d915:bcc3/1282c19:dd:d9:dd:c25:c25:d915:bcc3
1972c19:dd:d9:dd:c25:c25:d915:bcc4/1282c19:dd:d9:dd:c25:c25:d915:bcc4
1982c19:dd:d9:dd:c25:c25:d915:bcc5/1282c19:dd:d9:dd:c25:c25:d915:bcc5
1992c19:dd:d9:dd:c25:c25:d915:bcc6/1282c19:dd:d9:dd:c25:c25:d915:bcc6
2002c19:dd:d9:dd:c25:c25:d915:bcc7/1282c19:dd:d9:dd:c25:c25:d915:bcc7
2012c19:dd:d9:dd:c25:c25:d915:bcc8/1282c19:dd:d9:dd:c25:c25:d915:bcc8
2022c19:dd:d9:dd:c25:c25:d915:bcc9/1282c19:dd:d9:dd:c25:c25:d915:bcc9
2032c19:dd:d9:dd:c25:c25:d915:bcca/1282c19:dd:d9:dd:c25:c25:d915:bcca
2042c19:dd:d9:dd:c25:c25:d915:bccb/1282c19:dd:d9:dd:c25:c25:d915:bccb
2052c19:dd:d9:dd:c25:c25:d915:bccc/1282c19:dd:d9:dd:c25:c25:d915:bccc
2062c19:dd:d9:dd:c25:c25:d915:bccd/1282c19:dd:d9:dd:c25:c25:d915:bccd
2072c19:dd:d9:dd:c25:c25:d915:bcce/1282c19:dd:d9:dd:c25:c25:d915:bcce
2082c19:dd:d9:dd:c25:c25:d915:bccf/1282c19:dd:d9:dd:c25:c25:d915:bccf
2092c19:dd:d9:dd:c25:c25:d915:bcd0/1282c19:dd:d9:dd:c25:c25:d915:bcd0
2102c19:dd:d9:dd:c25:c25:d915:bcd1/1282c19:dd:d9:dd:c25:c25:d915:bcd1
2112c19:dd:d9:dd:c25:c25:d915:bcd2/1282c19:dd:d9:dd:c25:c25:d915:bcd2
2122c19:dd:d9:dd:c25:c25:d915:bcd3/1282c19:dd:d9:dd:c25:c25:d915:bcd3
2132c19:dd:d9:dd:c25:c25:d915:bcd4/1282c19:dd:d9:dd:c25:c25:d915:bcd4
2142c19:dd:d9:dd:c25:c25:d915:bcd5/1282c19:dd:d9:dd:c25:c25:d915:bcd5
2152c19:dd:d9:dd:c25:c25:d915:bcd6/1282c19:dd:d9:dd:c25:c25:d915:bcd6
2162c19:dd:d9:dd:c25:c25:d915:bcd7/1282c19:dd:d9:dd:c25:c25:d915:bcd7
2172c19:dd:d9:dd:c25:c25:d915:bcd8/1282c19:dd:d9:dd:c25:c25:d915:bcd8
2182c19:dd:d9:dd:c25:c25:d915:bcd9/1282c19:dd:d9:dd:c25:c25:d915:bcd9
2192c19:dd:d9:dd:c25:c25:d915:bcda/1282c19:dd:d9:dd:c25:c25:d915:bcda
2202c19:dd:d9:dd:c25:c25:d915:bcdb/1282c19:dd:d9:dd:c25:c25:d915:bcdb
2212c19:dd:d9:dd:c25:c25:d915:bcdc/1282c19:dd:d9:dd:c25:c25:d915:bcdc
2222c19:dd:d9:dd:c25:c25:d915:bcdd/1282c19:dd:d9:dd:c25:c25:d915:bcdd
2232c19:dd:d9:dd:c25:c25:d915:bcde/1282c19:dd:d9:dd:c25:c25:d915:bcde
2242c19:dd:d9:dd:c25:c25:d915:bcdf/1282c19:dd:d9:dd:c25:c25:d915:bcdf
2252c19:dd:d9:dd:c25:c25:d915:bce0/1282c19:dd:d9:dd:c25:c25:d915:bce0
2262c19:dd:d9:dd:c25:c25:d915:bce1/1282c19:dd:d9:dd:c25:c25:d915:bce1
2272c19:dd:d9:dd:c25:c25:d915:bce2/1282c19:dd:d9:dd:c25:c25:d915:bce2
2282c19:dd:d9:dd:c25:c25:d915:bce3/1282c19:dd:d9:dd:c25:c25:d915:bce3
2292c19:dd:d9:dd:c25:c25:d915:bce4/1282c19:dd:d9:dd:c25:c25:d915:bce4
2302c19:dd:d9:dd:c25:c25:d915:bce5/1282c19:dd:d9:dd:c25:c25:d915:bce5
2312c19:dd:d9:dd:c25:c25:d915:bce6/1282c19:dd:d9:dd:c25:c25:d915:bce6
2322c19:dd:d9:dd:c25:c25:d915:bce7/1282c19:dd:d9:dd:c25:c25:d915:bce7
2332c19:dd:d9:dd:c25:c25:d915:bce8/1282c19:dd:d9:dd:c25:c25:d915:bce8
2342c19:dd:d9:dd:c25:c25:d915:bce9/1282c19:dd:d9:dd:c25:c25:d915:bce9
2352c19:dd:d9:dd:c25:c25:d915:bcea/1282c19:dd:d9:dd:c25:c25:d915:bcea
2362c19:dd:d9:dd:c25:c25:d915:bceb/1282c19:dd:d9:dd:c25:c25:d915:bceb
2372c19:dd:d9:dd:c25:c25:d915:bcec/1282c19:dd:d9:dd:c25:c25:d915:bcec
2382c19:dd:d9:dd:c25:c25:d915:bced/1282c19:dd:d9:dd:c25:c25:d915:bced
2392c19:dd:d9:dd:c25:c25:d915:bcee/1282c19:dd:d9:dd:c25:c25:d915:bcee
2402c19:dd:d9:dd:c25:c25:d915:bcef/1282c19:dd:d9:dd:c25:c25:d915:bcef
2412c19:dd:d9:dd:c25:c25:d915:bcf0/1282c19:dd:d9:dd:c25:c25:d915:bcf0
2422c19:dd:d9:dd:c25:c25:d915:bcf1/1282c19:dd:d9:dd:c25:c25:d915:bcf1
2432c19:dd:d9:dd:c25:c25:d915:bcf2/1282c19:dd:d9:dd:c25:c25:d915:bcf2
2442c19:dd:d9:dd:c25:c25:d915:bcf3/1282c19:dd:d9:dd:c25:c25:d915:bcf3
2452c19:dd:d9:dd:c25:c25:d915:bcf4/1282c19:dd:d9:dd:c25:c25:d915:bcf4
2462c19:dd:d9:dd:c25:c25:d915:bcf5/1282c19:dd:d9:dd:c25:c25:d915:bcf5
2472c19:dd:d9:dd:c25:c25:d915:bcf6/1282c19:dd:d9:dd:c25:c25:d915:bcf6
2482c19:dd:d9:dd:c25:c25:d915:bcf7/1282c19:dd:d9:dd:c25:c25:d915:bcf7
2492c19:dd:d9:dd:c25:c25:d915:bcf8/1282c19:dd:d9:dd:c25:c25:d915:bcf8
2502c19:dd:d9:dd:c25:c25:d915:bcf9/1282c19:dd:d9:dd:c25:c25:d915:bcf9
2512c19:dd:d9:dd:c25:c25:d915:bcfa/1282c19:dd:d9:dd:c25:c25:d915:bcfa
2522c19:dd:d9:dd:c25:c25:d915:bcfb/1282c19:dd:d9:dd:c25:c25:d915:bcfb
2532c19:dd:d9:dd:c25:c25:d915:bcfc/1282c19:dd:d9:dd:c25:c25:d915:bcfc
2542c19:dd:d9:dd:c25:c25:d915:bcfd/1282c19:dd:d9:dd:c25:c25:d915:bcfd
2552c19:dd:d9:dd:c25:c25:d915:bcfe/1282c19:dd:d9:dd:c25:c25:d915:bcfe
2562c19:dd:d9:dd:c25:c25:d915:bcff/1282c19:dd:d9:dd:c25:c25:d915:bcff

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.