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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:ec00:eb00/120
First address
2c19:dd:d9:dd:c25:c25:ec00:eb00
Last address
2c19:dd:d9:dd:c25:c25:ec00:ebff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:ec00:eb00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
b.e.0.0.c.e.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:ec00:eb00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:ec00:eb00/1282c19:dd:d9:dd:c25:c25:ec00:eb00
22c19:dd:d9:dd:c25:c25:ec00:eb01/1282c19:dd:d9:dd:c25:c25:ec00:eb01
32c19:dd:d9:dd:c25:c25:ec00:eb02/1282c19:dd:d9:dd:c25:c25:ec00:eb02
42c19:dd:d9:dd:c25:c25:ec00:eb03/1282c19:dd:d9:dd:c25:c25:ec00:eb03
52c19:dd:d9:dd:c25:c25:ec00:eb04/1282c19:dd:d9:dd:c25:c25:ec00:eb04
62c19:dd:d9:dd:c25:c25:ec00:eb05/1282c19:dd:d9:dd:c25:c25:ec00:eb05
72c19:dd:d9:dd:c25:c25:ec00:eb06/1282c19:dd:d9:dd:c25:c25:ec00:eb06
82c19:dd:d9:dd:c25:c25:ec00:eb07/1282c19:dd:d9:dd:c25:c25:ec00:eb07
92c19:dd:d9:dd:c25:c25:ec00:eb08/1282c19:dd:d9:dd:c25:c25:ec00:eb08
102c19:dd:d9:dd:c25:c25:ec00:eb09/1282c19:dd:d9:dd:c25:c25:ec00:eb09
112c19:dd:d9:dd:c25:c25:ec00:eb0a/1282c19:dd:d9:dd:c25:c25:ec00:eb0a
122c19:dd:d9:dd:c25:c25:ec00:eb0b/1282c19:dd:d9:dd:c25:c25:ec00:eb0b
132c19:dd:d9:dd:c25:c25:ec00:eb0c/1282c19:dd:d9:dd:c25:c25:ec00:eb0c
142c19:dd:d9:dd:c25:c25:ec00:eb0d/1282c19:dd:d9:dd:c25:c25:ec00:eb0d
152c19:dd:d9:dd:c25:c25:ec00:eb0e/1282c19:dd:d9:dd:c25:c25:ec00:eb0e
162c19:dd:d9:dd:c25:c25:ec00:eb0f/1282c19:dd:d9:dd:c25:c25:ec00:eb0f
172c19:dd:d9:dd:c25:c25:ec00:eb10/1282c19:dd:d9:dd:c25:c25:ec00:eb10
182c19:dd:d9:dd:c25:c25:ec00:eb11/1282c19:dd:d9:dd:c25:c25:ec00:eb11
192c19:dd:d9:dd:c25:c25:ec00:eb12/1282c19:dd:d9:dd:c25:c25:ec00:eb12
202c19:dd:d9:dd:c25:c25:ec00:eb13/1282c19:dd:d9:dd:c25:c25:ec00:eb13
212c19:dd:d9:dd:c25:c25:ec00:eb14/1282c19:dd:d9:dd:c25:c25:ec00:eb14
222c19:dd:d9:dd:c25:c25:ec00:eb15/1282c19:dd:d9:dd:c25:c25:ec00:eb15
232c19:dd:d9:dd:c25:c25:ec00:eb16/1282c19:dd:d9:dd:c25:c25:ec00:eb16
242c19:dd:d9:dd:c25:c25:ec00:eb17/1282c19:dd:d9:dd:c25:c25:ec00:eb17
252c19:dd:d9:dd:c25:c25:ec00:eb18/1282c19:dd:d9:dd:c25:c25:ec00:eb18
262c19:dd:d9:dd:c25:c25:ec00:eb19/1282c19:dd:d9:dd:c25:c25:ec00:eb19
272c19:dd:d9:dd:c25:c25:ec00:eb1a/1282c19:dd:d9:dd:c25:c25:ec00:eb1a
282c19:dd:d9:dd:c25:c25:ec00:eb1b/1282c19:dd:d9:dd:c25:c25:ec00:eb1b
292c19:dd:d9:dd:c25:c25:ec00:eb1c/1282c19:dd:d9:dd:c25:c25:ec00:eb1c
302c19:dd:d9:dd:c25:c25:ec00:eb1d/1282c19:dd:d9:dd:c25:c25:ec00:eb1d
312c19:dd:d9:dd:c25:c25:ec00:eb1e/1282c19:dd:d9:dd:c25:c25:ec00:eb1e
322c19:dd:d9:dd:c25:c25:ec00:eb1f/1282c19:dd:d9:dd:c25:c25:ec00:eb1f
332c19:dd:d9:dd:c25:c25:ec00:eb20/1282c19:dd:d9:dd:c25:c25:ec00:eb20
342c19:dd:d9:dd:c25:c25:ec00:eb21/1282c19:dd:d9:dd:c25:c25:ec00:eb21
352c19:dd:d9:dd:c25:c25:ec00:eb22/1282c19:dd:d9:dd:c25:c25:ec00:eb22
362c19:dd:d9:dd:c25:c25:ec00:eb23/1282c19:dd:d9:dd:c25:c25:ec00:eb23
372c19:dd:d9:dd:c25:c25:ec00:eb24/1282c19:dd:d9:dd:c25:c25:ec00:eb24
382c19:dd:d9:dd:c25:c25:ec00:eb25/1282c19:dd:d9:dd:c25:c25:ec00:eb25
392c19:dd:d9:dd:c25:c25:ec00:eb26/1282c19:dd:d9:dd:c25:c25:ec00:eb26
402c19:dd:d9:dd:c25:c25:ec00:eb27/1282c19:dd:d9:dd:c25:c25:ec00:eb27
412c19:dd:d9:dd:c25:c25:ec00:eb28/1282c19:dd:d9:dd:c25:c25:ec00:eb28
422c19:dd:d9:dd:c25:c25:ec00:eb29/1282c19:dd:d9:dd:c25:c25:ec00:eb29
432c19:dd:d9:dd:c25:c25:ec00:eb2a/1282c19:dd:d9:dd:c25:c25:ec00:eb2a
442c19:dd:d9:dd:c25:c25:ec00:eb2b/1282c19:dd:d9:dd:c25:c25:ec00:eb2b
452c19:dd:d9:dd:c25:c25:ec00:eb2c/1282c19:dd:d9:dd:c25:c25:ec00:eb2c
462c19:dd:d9:dd:c25:c25:ec00:eb2d/1282c19:dd:d9:dd:c25:c25:ec00:eb2d
472c19:dd:d9:dd:c25:c25:ec00:eb2e/1282c19:dd:d9:dd:c25:c25:ec00:eb2e
482c19:dd:d9:dd:c25:c25:ec00:eb2f/1282c19:dd:d9:dd:c25:c25:ec00:eb2f
492c19:dd:d9:dd:c25:c25:ec00:eb30/1282c19:dd:d9:dd:c25:c25:ec00:eb30
502c19:dd:d9:dd:c25:c25:ec00:eb31/1282c19:dd:d9:dd:c25:c25:ec00:eb31
512c19:dd:d9:dd:c25:c25:ec00:eb32/1282c19:dd:d9:dd:c25:c25:ec00:eb32
522c19:dd:d9:dd:c25:c25:ec00:eb33/1282c19:dd:d9:dd:c25:c25:ec00:eb33
532c19:dd:d9:dd:c25:c25:ec00:eb34/1282c19:dd:d9:dd:c25:c25:ec00:eb34
542c19:dd:d9:dd:c25:c25:ec00:eb35/1282c19:dd:d9:dd:c25:c25:ec00:eb35
552c19:dd:d9:dd:c25:c25:ec00:eb36/1282c19:dd:d9:dd:c25:c25:ec00:eb36
562c19:dd:d9:dd:c25:c25:ec00:eb37/1282c19:dd:d9:dd:c25:c25:ec00:eb37
572c19:dd:d9:dd:c25:c25:ec00:eb38/1282c19:dd:d9:dd:c25:c25:ec00:eb38
582c19:dd:d9:dd:c25:c25:ec00:eb39/1282c19:dd:d9:dd:c25:c25:ec00:eb39
592c19:dd:d9:dd:c25:c25:ec00:eb3a/1282c19:dd:d9:dd:c25:c25:ec00:eb3a
602c19:dd:d9:dd:c25:c25:ec00:eb3b/1282c19:dd:d9:dd:c25:c25:ec00:eb3b
612c19:dd:d9:dd:c25:c25:ec00:eb3c/1282c19:dd:d9:dd:c25:c25:ec00:eb3c
622c19:dd:d9:dd:c25:c25:ec00:eb3d/1282c19:dd:d9:dd:c25:c25:ec00:eb3d
632c19:dd:d9:dd:c25:c25:ec00:eb3e/1282c19:dd:d9:dd:c25:c25:ec00:eb3e
642c19:dd:d9:dd:c25:c25:ec00:eb3f/1282c19:dd:d9:dd:c25:c25:ec00:eb3f
652c19:dd:d9:dd:c25:c25:ec00:eb40/1282c19:dd:d9:dd:c25:c25:ec00:eb40
662c19:dd:d9:dd:c25:c25:ec00:eb41/1282c19:dd:d9:dd:c25:c25:ec00:eb41
672c19:dd:d9:dd:c25:c25:ec00:eb42/1282c19:dd:d9:dd:c25:c25:ec00:eb42
682c19:dd:d9:dd:c25:c25:ec00:eb43/1282c19:dd:d9:dd:c25:c25:ec00:eb43
692c19:dd:d9:dd:c25:c25:ec00:eb44/1282c19:dd:d9:dd:c25:c25:ec00:eb44
702c19:dd:d9:dd:c25:c25:ec00:eb45/1282c19:dd:d9:dd:c25:c25:ec00:eb45
712c19:dd:d9:dd:c25:c25:ec00:eb46/1282c19:dd:d9:dd:c25:c25:ec00:eb46
722c19:dd:d9:dd:c25:c25:ec00:eb47/1282c19:dd:d9:dd:c25:c25:ec00:eb47
732c19:dd:d9:dd:c25:c25:ec00:eb48/1282c19:dd:d9:dd:c25:c25:ec00:eb48
742c19:dd:d9:dd:c25:c25:ec00:eb49/1282c19:dd:d9:dd:c25:c25:ec00:eb49
752c19:dd:d9:dd:c25:c25:ec00:eb4a/1282c19:dd:d9:dd:c25:c25:ec00:eb4a
762c19:dd:d9:dd:c25:c25:ec00:eb4b/1282c19:dd:d9:dd:c25:c25:ec00:eb4b
772c19:dd:d9:dd:c25:c25:ec00:eb4c/1282c19:dd:d9:dd:c25:c25:ec00:eb4c
782c19:dd:d9:dd:c25:c25:ec00:eb4d/1282c19:dd:d9:dd:c25:c25:ec00:eb4d
792c19:dd:d9:dd:c25:c25:ec00:eb4e/1282c19:dd:d9:dd:c25:c25:ec00:eb4e
802c19:dd:d9:dd:c25:c25:ec00:eb4f/1282c19:dd:d9:dd:c25:c25:ec00:eb4f
812c19:dd:d9:dd:c25:c25:ec00:eb50/1282c19:dd:d9:dd:c25:c25:ec00:eb50
822c19:dd:d9:dd:c25:c25:ec00:eb51/1282c19:dd:d9:dd:c25:c25:ec00:eb51
832c19:dd:d9:dd:c25:c25:ec00:eb52/1282c19:dd:d9:dd:c25:c25:ec00:eb52
842c19:dd:d9:dd:c25:c25:ec00:eb53/1282c19:dd:d9:dd:c25:c25:ec00:eb53
852c19:dd:d9:dd:c25:c25:ec00:eb54/1282c19:dd:d9:dd:c25:c25:ec00:eb54
862c19:dd:d9:dd:c25:c25:ec00:eb55/1282c19:dd:d9:dd:c25:c25:ec00:eb55
872c19:dd:d9:dd:c25:c25:ec00:eb56/1282c19:dd:d9:dd:c25:c25:ec00:eb56
882c19:dd:d9:dd:c25:c25:ec00:eb57/1282c19:dd:d9:dd:c25:c25:ec00:eb57
892c19:dd:d9:dd:c25:c25:ec00:eb58/1282c19:dd:d9:dd:c25:c25:ec00:eb58
902c19:dd:d9:dd:c25:c25:ec00:eb59/1282c19:dd:d9:dd:c25:c25:ec00:eb59
912c19:dd:d9:dd:c25:c25:ec00:eb5a/1282c19:dd:d9:dd:c25:c25:ec00:eb5a
922c19:dd:d9:dd:c25:c25:ec00:eb5b/1282c19:dd:d9:dd:c25:c25:ec00:eb5b
932c19:dd:d9:dd:c25:c25:ec00:eb5c/1282c19:dd:d9:dd:c25:c25:ec00:eb5c
942c19:dd:d9:dd:c25:c25:ec00:eb5d/1282c19:dd:d9:dd:c25:c25:ec00:eb5d
952c19:dd:d9:dd:c25:c25:ec00:eb5e/1282c19:dd:d9:dd:c25:c25:ec00:eb5e
962c19:dd:d9:dd:c25:c25:ec00:eb5f/1282c19:dd:d9:dd:c25:c25:ec00:eb5f
972c19:dd:d9:dd:c25:c25:ec00:eb60/1282c19:dd:d9:dd:c25:c25:ec00:eb60
982c19:dd:d9:dd:c25:c25:ec00:eb61/1282c19:dd:d9:dd:c25:c25:ec00:eb61
992c19:dd:d9:dd:c25:c25:ec00:eb62/1282c19:dd:d9:dd:c25:c25:ec00:eb62
1002c19:dd:d9:dd:c25:c25:ec00:eb63/1282c19:dd:d9:dd:c25:c25:ec00:eb63
1012c19:dd:d9:dd:c25:c25:ec00:eb64/1282c19:dd:d9:dd:c25:c25:ec00:eb64
1022c19:dd:d9:dd:c25:c25:ec00:eb65/1282c19:dd:d9:dd:c25:c25:ec00:eb65
1032c19:dd:d9:dd:c25:c25:ec00:eb66/1282c19:dd:d9:dd:c25:c25:ec00:eb66
1042c19:dd:d9:dd:c25:c25:ec00:eb67/1282c19:dd:d9:dd:c25:c25:ec00:eb67
1052c19:dd:d9:dd:c25:c25:ec00:eb68/1282c19:dd:d9:dd:c25:c25:ec00:eb68
1062c19:dd:d9:dd:c25:c25:ec00:eb69/1282c19:dd:d9:dd:c25:c25:ec00:eb69
1072c19:dd:d9:dd:c25:c25:ec00:eb6a/1282c19:dd:d9:dd:c25:c25:ec00:eb6a
1082c19:dd:d9:dd:c25:c25:ec00:eb6b/1282c19:dd:d9:dd:c25:c25:ec00:eb6b
1092c19:dd:d9:dd:c25:c25:ec00:eb6c/1282c19:dd:d9:dd:c25:c25:ec00:eb6c
1102c19:dd:d9:dd:c25:c25:ec00:eb6d/1282c19:dd:d9:dd:c25:c25:ec00:eb6d
1112c19:dd:d9:dd:c25:c25:ec00:eb6e/1282c19:dd:d9:dd:c25:c25:ec00:eb6e
1122c19:dd:d9:dd:c25:c25:ec00:eb6f/1282c19:dd:d9:dd:c25:c25:ec00:eb6f
1132c19:dd:d9:dd:c25:c25:ec00:eb70/1282c19:dd:d9:dd:c25:c25:ec00:eb70
1142c19:dd:d9:dd:c25:c25:ec00:eb71/1282c19:dd:d9:dd:c25:c25:ec00:eb71
1152c19:dd:d9:dd:c25:c25:ec00:eb72/1282c19:dd:d9:dd:c25:c25:ec00:eb72
1162c19:dd:d9:dd:c25:c25:ec00:eb73/1282c19:dd:d9:dd:c25:c25:ec00:eb73
1172c19:dd:d9:dd:c25:c25:ec00:eb74/1282c19:dd:d9:dd:c25:c25:ec00:eb74
1182c19:dd:d9:dd:c25:c25:ec00:eb75/1282c19:dd:d9:dd:c25:c25:ec00:eb75
1192c19:dd:d9:dd:c25:c25:ec00:eb76/1282c19:dd:d9:dd:c25:c25:ec00:eb76
1202c19:dd:d9:dd:c25:c25:ec00:eb77/1282c19:dd:d9:dd:c25:c25:ec00:eb77
1212c19:dd:d9:dd:c25:c25:ec00:eb78/1282c19:dd:d9:dd:c25:c25:ec00:eb78
1222c19:dd:d9:dd:c25:c25:ec00:eb79/1282c19:dd:d9:dd:c25:c25:ec00:eb79
1232c19:dd:d9:dd:c25:c25:ec00:eb7a/1282c19:dd:d9:dd:c25:c25:ec00:eb7a
1242c19:dd:d9:dd:c25:c25:ec00:eb7b/1282c19:dd:d9:dd:c25:c25:ec00:eb7b
1252c19:dd:d9:dd:c25:c25:ec00:eb7c/1282c19:dd:d9:dd:c25:c25:ec00:eb7c
1262c19:dd:d9:dd:c25:c25:ec00:eb7d/1282c19:dd:d9:dd:c25:c25:ec00:eb7d
1272c19:dd:d9:dd:c25:c25:ec00:eb7e/1282c19:dd:d9:dd:c25:c25:ec00:eb7e
1282c19:dd:d9:dd:c25:c25:ec00:eb7f/1282c19:dd:d9:dd:c25:c25:ec00:eb7f
1292c19:dd:d9:dd:c25:c25:ec00:eb80/1282c19:dd:d9:dd:c25:c25:ec00:eb80
1302c19:dd:d9:dd:c25:c25:ec00:eb81/1282c19:dd:d9:dd:c25:c25:ec00:eb81
1312c19:dd:d9:dd:c25:c25:ec00:eb82/1282c19:dd:d9:dd:c25:c25:ec00:eb82
1322c19:dd:d9:dd:c25:c25:ec00:eb83/1282c19:dd:d9:dd:c25:c25:ec00:eb83
1332c19:dd:d9:dd:c25:c25:ec00:eb84/1282c19:dd:d9:dd:c25:c25:ec00:eb84
1342c19:dd:d9:dd:c25:c25:ec00:eb85/1282c19:dd:d9:dd:c25:c25:ec00:eb85
1352c19:dd:d9:dd:c25:c25:ec00:eb86/1282c19:dd:d9:dd:c25:c25:ec00:eb86
1362c19:dd:d9:dd:c25:c25:ec00:eb87/1282c19:dd:d9:dd:c25:c25:ec00:eb87
1372c19:dd:d9:dd:c25:c25:ec00:eb88/1282c19:dd:d9:dd:c25:c25:ec00:eb88
1382c19:dd:d9:dd:c25:c25:ec00:eb89/1282c19:dd:d9:dd:c25:c25:ec00:eb89
1392c19:dd:d9:dd:c25:c25:ec00:eb8a/1282c19:dd:d9:dd:c25:c25:ec00:eb8a
1402c19:dd:d9:dd:c25:c25:ec00:eb8b/1282c19:dd:d9:dd:c25:c25:ec00:eb8b
1412c19:dd:d9:dd:c25:c25:ec00:eb8c/1282c19:dd:d9:dd:c25:c25:ec00:eb8c
1422c19:dd:d9:dd:c25:c25:ec00:eb8d/1282c19:dd:d9:dd:c25:c25:ec00:eb8d
1432c19:dd:d9:dd:c25:c25:ec00:eb8e/1282c19:dd:d9:dd:c25:c25:ec00:eb8e
1442c19:dd:d9:dd:c25:c25:ec00:eb8f/1282c19:dd:d9:dd:c25:c25:ec00:eb8f
1452c19:dd:d9:dd:c25:c25:ec00:eb90/1282c19:dd:d9:dd:c25:c25:ec00:eb90
1462c19:dd:d9:dd:c25:c25:ec00:eb91/1282c19:dd:d9:dd:c25:c25:ec00:eb91
1472c19:dd:d9:dd:c25:c25:ec00:eb92/1282c19:dd:d9:dd:c25:c25:ec00:eb92
1482c19:dd:d9:dd:c25:c25:ec00:eb93/1282c19:dd:d9:dd:c25:c25:ec00:eb93
1492c19:dd:d9:dd:c25:c25:ec00:eb94/1282c19:dd:d9:dd:c25:c25:ec00:eb94
1502c19:dd:d9:dd:c25:c25:ec00:eb95/1282c19:dd:d9:dd:c25:c25:ec00:eb95
1512c19:dd:d9:dd:c25:c25:ec00:eb96/1282c19:dd:d9:dd:c25:c25:ec00:eb96
1522c19:dd:d9:dd:c25:c25:ec00:eb97/1282c19:dd:d9:dd:c25:c25:ec00:eb97
1532c19:dd:d9:dd:c25:c25:ec00:eb98/1282c19:dd:d9:dd:c25:c25:ec00:eb98
1542c19:dd:d9:dd:c25:c25:ec00:eb99/1282c19:dd:d9:dd:c25:c25:ec00:eb99
1552c19:dd:d9:dd:c25:c25:ec00:eb9a/1282c19:dd:d9:dd:c25:c25:ec00:eb9a
1562c19:dd:d9:dd:c25:c25:ec00:eb9b/1282c19:dd:d9:dd:c25:c25:ec00:eb9b
1572c19:dd:d9:dd:c25:c25:ec00:eb9c/1282c19:dd:d9:dd:c25:c25:ec00:eb9c
1582c19:dd:d9:dd:c25:c25:ec00:eb9d/1282c19:dd:d9:dd:c25:c25:ec00:eb9d
1592c19:dd:d9:dd:c25:c25:ec00:eb9e/1282c19:dd:d9:dd:c25:c25:ec00:eb9e
1602c19:dd:d9:dd:c25:c25:ec00:eb9f/1282c19:dd:d9:dd:c25:c25:ec00:eb9f
1612c19:dd:d9:dd:c25:c25:ec00:eba0/1282c19:dd:d9:dd:c25:c25:ec00:eba0
1622c19:dd:d9:dd:c25:c25:ec00:eba1/1282c19:dd:d9:dd:c25:c25:ec00:eba1
1632c19:dd:d9:dd:c25:c25:ec00:eba2/1282c19:dd:d9:dd:c25:c25:ec00:eba2
1642c19:dd:d9:dd:c25:c25:ec00:eba3/1282c19:dd:d9:dd:c25:c25:ec00:eba3
1652c19:dd:d9:dd:c25:c25:ec00:eba4/1282c19:dd:d9:dd:c25:c25:ec00:eba4
1662c19:dd:d9:dd:c25:c25:ec00:eba5/1282c19:dd:d9:dd:c25:c25:ec00:eba5
1672c19:dd:d9:dd:c25:c25:ec00:eba6/1282c19:dd:d9:dd:c25:c25:ec00:eba6
1682c19:dd:d9:dd:c25:c25:ec00:eba7/1282c19:dd:d9:dd:c25:c25:ec00:eba7
1692c19:dd:d9:dd:c25:c25:ec00:eba8/1282c19:dd:d9:dd:c25:c25:ec00:eba8
1702c19:dd:d9:dd:c25:c25:ec00:eba9/1282c19:dd:d9:dd:c25:c25:ec00:eba9
1712c19:dd:d9:dd:c25:c25:ec00:ebaa/1282c19:dd:d9:dd:c25:c25:ec00:ebaa
1722c19:dd:d9:dd:c25:c25:ec00:ebab/1282c19:dd:d9:dd:c25:c25:ec00:ebab
1732c19:dd:d9:dd:c25:c25:ec00:ebac/1282c19:dd:d9:dd:c25:c25:ec00:ebac
1742c19:dd:d9:dd:c25:c25:ec00:ebad/1282c19:dd:d9:dd:c25:c25:ec00:ebad
1752c19:dd:d9:dd:c25:c25:ec00:ebae/1282c19:dd:d9:dd:c25:c25:ec00:ebae
1762c19:dd:d9:dd:c25:c25:ec00:ebaf/1282c19:dd:d9:dd:c25:c25:ec00:ebaf
1772c19:dd:d9:dd:c25:c25:ec00:ebb0/1282c19:dd:d9:dd:c25:c25:ec00:ebb0
1782c19:dd:d9:dd:c25:c25:ec00:ebb1/1282c19:dd:d9:dd:c25:c25:ec00:ebb1
1792c19:dd:d9:dd:c25:c25:ec00:ebb2/1282c19:dd:d9:dd:c25:c25:ec00:ebb2
1802c19:dd:d9:dd:c25:c25:ec00:ebb3/1282c19:dd:d9:dd:c25:c25:ec00:ebb3
1812c19:dd:d9:dd:c25:c25:ec00:ebb4/1282c19:dd:d9:dd:c25:c25:ec00:ebb4
1822c19:dd:d9:dd:c25:c25:ec00:ebb5/1282c19:dd:d9:dd:c25:c25:ec00:ebb5
1832c19:dd:d9:dd:c25:c25:ec00:ebb6/1282c19:dd:d9:dd:c25:c25:ec00:ebb6
1842c19:dd:d9:dd:c25:c25:ec00:ebb7/1282c19:dd:d9:dd:c25:c25:ec00:ebb7
1852c19:dd:d9:dd:c25:c25:ec00:ebb8/1282c19:dd:d9:dd:c25:c25:ec00:ebb8
1862c19:dd:d9:dd:c25:c25:ec00:ebb9/1282c19:dd:d9:dd:c25:c25:ec00:ebb9
1872c19:dd:d9:dd:c25:c25:ec00:ebba/1282c19:dd:d9:dd:c25:c25:ec00:ebba
1882c19:dd:d9:dd:c25:c25:ec00:ebbb/1282c19:dd:d9:dd:c25:c25:ec00:ebbb
1892c19:dd:d9:dd:c25:c25:ec00:ebbc/1282c19:dd:d9:dd:c25:c25:ec00:ebbc
1902c19:dd:d9:dd:c25:c25:ec00:ebbd/1282c19:dd:d9:dd:c25:c25:ec00:ebbd
1912c19:dd:d9:dd:c25:c25:ec00:ebbe/1282c19:dd:d9:dd:c25:c25:ec00:ebbe
1922c19:dd:d9:dd:c25:c25:ec00:ebbf/1282c19:dd:d9:dd:c25:c25:ec00:ebbf
1932c19:dd:d9:dd:c25:c25:ec00:ebc0/1282c19:dd:d9:dd:c25:c25:ec00:ebc0
1942c19:dd:d9:dd:c25:c25:ec00:ebc1/1282c19:dd:d9:dd:c25:c25:ec00:ebc1
1952c19:dd:d9:dd:c25:c25:ec00:ebc2/1282c19:dd:d9:dd:c25:c25:ec00:ebc2
1962c19:dd:d9:dd:c25:c25:ec00:ebc3/1282c19:dd:d9:dd:c25:c25:ec00:ebc3
1972c19:dd:d9:dd:c25:c25:ec00:ebc4/1282c19:dd:d9:dd:c25:c25:ec00:ebc4
1982c19:dd:d9:dd:c25:c25:ec00:ebc5/1282c19:dd:d9:dd:c25:c25:ec00:ebc5
1992c19:dd:d9:dd:c25:c25:ec00:ebc6/1282c19:dd:d9:dd:c25:c25:ec00:ebc6
2002c19:dd:d9:dd:c25:c25:ec00:ebc7/1282c19:dd:d9:dd:c25:c25:ec00:ebc7
2012c19:dd:d9:dd:c25:c25:ec00:ebc8/1282c19:dd:d9:dd:c25:c25:ec00:ebc8
2022c19:dd:d9:dd:c25:c25:ec00:ebc9/1282c19:dd:d9:dd:c25:c25:ec00:ebc9
2032c19:dd:d9:dd:c25:c25:ec00:ebca/1282c19:dd:d9:dd:c25:c25:ec00:ebca
2042c19:dd:d9:dd:c25:c25:ec00:ebcb/1282c19:dd:d9:dd:c25:c25:ec00:ebcb
2052c19:dd:d9:dd:c25:c25:ec00:ebcc/1282c19:dd:d9:dd:c25:c25:ec00:ebcc
2062c19:dd:d9:dd:c25:c25:ec00:ebcd/1282c19:dd:d9:dd:c25:c25:ec00:ebcd
2072c19:dd:d9:dd:c25:c25:ec00:ebce/1282c19:dd:d9:dd:c25:c25:ec00:ebce
2082c19:dd:d9:dd:c25:c25:ec00:ebcf/1282c19:dd:d9:dd:c25:c25:ec00:ebcf
2092c19:dd:d9:dd:c25:c25:ec00:ebd0/1282c19:dd:d9:dd:c25:c25:ec00:ebd0
2102c19:dd:d9:dd:c25:c25:ec00:ebd1/1282c19:dd:d9:dd:c25:c25:ec00:ebd1
2112c19:dd:d9:dd:c25:c25:ec00:ebd2/1282c19:dd:d9:dd:c25:c25:ec00:ebd2
2122c19:dd:d9:dd:c25:c25:ec00:ebd3/1282c19:dd:d9:dd:c25:c25:ec00:ebd3
2132c19:dd:d9:dd:c25:c25:ec00:ebd4/1282c19:dd:d9:dd:c25:c25:ec00:ebd4
2142c19:dd:d9:dd:c25:c25:ec00:ebd5/1282c19:dd:d9:dd:c25:c25:ec00:ebd5
2152c19:dd:d9:dd:c25:c25:ec00:ebd6/1282c19:dd:d9:dd:c25:c25:ec00:ebd6
2162c19:dd:d9:dd:c25:c25:ec00:ebd7/1282c19:dd:d9:dd:c25:c25:ec00:ebd7
2172c19:dd:d9:dd:c25:c25:ec00:ebd8/1282c19:dd:d9:dd:c25:c25:ec00:ebd8
2182c19:dd:d9:dd:c25:c25:ec00:ebd9/1282c19:dd:d9:dd:c25:c25:ec00:ebd9
2192c19:dd:d9:dd:c25:c25:ec00:ebda/1282c19:dd:d9:dd:c25:c25:ec00:ebda
2202c19:dd:d9:dd:c25:c25:ec00:ebdb/1282c19:dd:d9:dd:c25:c25:ec00:ebdb
2212c19:dd:d9:dd:c25:c25:ec00:ebdc/1282c19:dd:d9:dd:c25:c25:ec00:ebdc
2222c19:dd:d9:dd:c25:c25:ec00:ebdd/1282c19:dd:d9:dd:c25:c25:ec00:ebdd
2232c19:dd:d9:dd:c25:c25:ec00:ebde/1282c19:dd:d9:dd:c25:c25:ec00:ebde
2242c19:dd:d9:dd:c25:c25:ec00:ebdf/1282c19:dd:d9:dd:c25:c25:ec00:ebdf
2252c19:dd:d9:dd:c25:c25:ec00:ebe0/1282c19:dd:d9:dd:c25:c25:ec00:ebe0
2262c19:dd:d9:dd:c25:c25:ec00:ebe1/1282c19:dd:d9:dd:c25:c25:ec00:ebe1
2272c19:dd:d9:dd:c25:c25:ec00:ebe2/1282c19:dd:d9:dd:c25:c25:ec00:ebe2
2282c19:dd:d9:dd:c25:c25:ec00:ebe3/1282c19:dd:d9:dd:c25:c25:ec00:ebe3
2292c19:dd:d9:dd:c25:c25:ec00:ebe4/1282c19:dd:d9:dd:c25:c25:ec00:ebe4
2302c19:dd:d9:dd:c25:c25:ec00:ebe5/1282c19:dd:d9:dd:c25:c25:ec00:ebe5
2312c19:dd:d9:dd:c25:c25:ec00:ebe6/1282c19:dd:d9:dd:c25:c25:ec00:ebe6
2322c19:dd:d9:dd:c25:c25:ec00:ebe7/1282c19:dd:d9:dd:c25:c25:ec00:ebe7
2332c19:dd:d9:dd:c25:c25:ec00:ebe8/1282c19:dd:d9:dd:c25:c25:ec00:ebe8
2342c19:dd:d9:dd:c25:c25:ec00:ebe9/1282c19:dd:d9:dd:c25:c25:ec00:ebe9
2352c19:dd:d9:dd:c25:c25:ec00:ebea/1282c19:dd:d9:dd:c25:c25:ec00:ebea
2362c19:dd:d9:dd:c25:c25:ec00:ebeb/1282c19:dd:d9:dd:c25:c25:ec00:ebeb
2372c19:dd:d9:dd:c25:c25:ec00:ebec/1282c19:dd:d9:dd:c25:c25:ec00:ebec
2382c19:dd:d9:dd:c25:c25:ec00:ebed/1282c19:dd:d9:dd:c25:c25:ec00:ebed
2392c19:dd:d9:dd:c25:c25:ec00:ebee/1282c19:dd:d9:dd:c25:c25:ec00:ebee
2402c19:dd:d9:dd:c25:c25:ec00:ebef/1282c19:dd:d9:dd:c25:c25:ec00:ebef
2412c19:dd:d9:dd:c25:c25:ec00:ebf0/1282c19:dd:d9:dd:c25:c25:ec00:ebf0
2422c19:dd:d9:dd:c25:c25:ec00:ebf1/1282c19:dd:d9:dd:c25:c25:ec00:ebf1
2432c19:dd:d9:dd:c25:c25:ec00:ebf2/1282c19:dd:d9:dd:c25:c25:ec00:ebf2
2442c19:dd:d9:dd:c25:c25:ec00:ebf3/1282c19:dd:d9:dd:c25:c25:ec00:ebf3
2452c19:dd:d9:dd:c25:c25:ec00:ebf4/1282c19:dd:d9:dd:c25:c25:ec00:ebf4
2462c19:dd:d9:dd:c25:c25:ec00:ebf5/1282c19:dd:d9:dd:c25:c25:ec00:ebf5
2472c19:dd:d9:dd:c25:c25:ec00:ebf6/1282c19:dd:d9:dd:c25:c25:ec00:ebf6
2482c19:dd:d9:dd:c25:c25:ec00:ebf7/1282c19:dd:d9:dd:c25:c25:ec00:ebf7
2492c19:dd:d9:dd:c25:c25:ec00:ebf8/1282c19:dd:d9:dd:c25:c25:ec00:ebf8
2502c19:dd:d9:dd:c25:c25:ec00:ebf9/1282c19:dd:d9:dd:c25:c25:ec00:ebf9
2512c19:dd:d9:dd:c25:c25:ec00:ebfa/1282c19:dd:d9:dd:c25:c25:ec00:ebfa
2522c19:dd:d9:dd:c25:c25:ec00:ebfb/1282c19:dd:d9:dd:c25:c25:ec00:ebfb
2532c19:dd:d9:dd:c25:c25:ec00:ebfc/1282c19:dd:d9:dd:c25:c25:ec00:ebfc
2542c19:dd:d9:dd:c25:c25:ec00:ebfd/1282c19:dd:d9:dd:c25:c25:ec00:ebfd
2552c19:dd:d9:dd:c25:c25:ec00:ebfe/1282c19:dd:d9:dd:c25:c25:ec00:ebfe
2562c19:dd:d9:dd:c25:c25:ec00:ebff/1282c19:dd:d9:dd:c25:c25:ec00:ebff

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.