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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:bc19:2d00/120
First address
2c19:dd:d9:dd:c25:c25:bc19:2d00
Last address
2c19:dd:d9:dd:c25:c25:bc19:2dff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:bc19:2d00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
d.2.9.1.c.b.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:bc19:2d00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:bc19:2d00/1282c19:dd:d9:dd:c25:c25:bc19:2d00
22c19:dd:d9:dd:c25:c25:bc19:2d01/1282c19:dd:d9:dd:c25:c25:bc19:2d01
32c19:dd:d9:dd:c25:c25:bc19:2d02/1282c19:dd:d9:dd:c25:c25:bc19:2d02
42c19:dd:d9:dd:c25:c25:bc19:2d03/1282c19:dd:d9:dd:c25:c25:bc19:2d03
52c19:dd:d9:dd:c25:c25:bc19:2d04/1282c19:dd:d9:dd:c25:c25:bc19:2d04
62c19:dd:d9:dd:c25:c25:bc19:2d05/1282c19:dd:d9:dd:c25:c25:bc19:2d05
72c19:dd:d9:dd:c25:c25:bc19:2d06/1282c19:dd:d9:dd:c25:c25:bc19:2d06
82c19:dd:d9:dd:c25:c25:bc19:2d07/1282c19:dd:d9:dd:c25:c25:bc19:2d07
92c19:dd:d9:dd:c25:c25:bc19:2d08/1282c19:dd:d9:dd:c25:c25:bc19:2d08
102c19:dd:d9:dd:c25:c25:bc19:2d09/1282c19:dd:d9:dd:c25:c25:bc19:2d09
112c19:dd:d9:dd:c25:c25:bc19:2d0a/1282c19:dd:d9:dd:c25:c25:bc19:2d0a
122c19:dd:d9:dd:c25:c25:bc19:2d0b/1282c19:dd:d9:dd:c25:c25:bc19:2d0b
132c19:dd:d9:dd:c25:c25:bc19:2d0c/1282c19:dd:d9:dd:c25:c25:bc19:2d0c
142c19:dd:d9:dd:c25:c25:bc19:2d0d/1282c19:dd:d9:dd:c25:c25:bc19:2d0d
152c19:dd:d9:dd:c25:c25:bc19:2d0e/1282c19:dd:d9:dd:c25:c25:bc19:2d0e
162c19:dd:d9:dd:c25:c25:bc19:2d0f/1282c19:dd:d9:dd:c25:c25:bc19:2d0f
172c19:dd:d9:dd:c25:c25:bc19:2d10/1282c19:dd:d9:dd:c25:c25:bc19:2d10
182c19:dd:d9:dd:c25:c25:bc19:2d11/1282c19:dd:d9:dd:c25:c25:bc19:2d11
192c19:dd:d9:dd:c25:c25:bc19:2d12/1282c19:dd:d9:dd:c25:c25:bc19:2d12
202c19:dd:d9:dd:c25:c25:bc19:2d13/1282c19:dd:d9:dd:c25:c25:bc19:2d13
212c19:dd:d9:dd:c25:c25:bc19:2d14/1282c19:dd:d9:dd:c25:c25:bc19:2d14
222c19:dd:d9:dd:c25:c25:bc19:2d15/1282c19:dd:d9:dd:c25:c25:bc19:2d15
232c19:dd:d9:dd:c25:c25:bc19:2d16/1282c19:dd:d9:dd:c25:c25:bc19:2d16
242c19:dd:d9:dd:c25:c25:bc19:2d17/1282c19:dd:d9:dd:c25:c25:bc19:2d17
252c19:dd:d9:dd:c25:c25:bc19:2d18/1282c19:dd:d9:dd:c25:c25:bc19:2d18
262c19:dd:d9:dd:c25:c25:bc19:2d19/1282c19:dd:d9:dd:c25:c25:bc19:2d19
272c19:dd:d9:dd:c25:c25:bc19:2d1a/1282c19:dd:d9:dd:c25:c25:bc19:2d1a
282c19:dd:d9:dd:c25:c25:bc19:2d1b/1282c19:dd:d9:dd:c25:c25:bc19:2d1b
292c19:dd:d9:dd:c25:c25:bc19:2d1c/1282c19:dd:d9:dd:c25:c25:bc19:2d1c
302c19:dd:d9:dd:c25:c25:bc19:2d1d/1282c19:dd:d9:dd:c25:c25:bc19:2d1d
312c19:dd:d9:dd:c25:c25:bc19:2d1e/1282c19:dd:d9:dd:c25:c25:bc19:2d1e
322c19:dd:d9:dd:c25:c25:bc19:2d1f/1282c19:dd:d9:dd:c25:c25:bc19:2d1f
332c19:dd:d9:dd:c25:c25:bc19:2d20/1282c19:dd:d9:dd:c25:c25:bc19:2d20
342c19:dd:d9:dd:c25:c25:bc19:2d21/1282c19:dd:d9:dd:c25:c25:bc19:2d21
352c19:dd:d9:dd:c25:c25:bc19:2d22/1282c19:dd:d9:dd:c25:c25:bc19:2d22
362c19:dd:d9:dd:c25:c25:bc19:2d23/1282c19:dd:d9:dd:c25:c25:bc19:2d23
372c19:dd:d9:dd:c25:c25:bc19:2d24/1282c19:dd:d9:dd:c25:c25:bc19:2d24
382c19:dd:d9:dd:c25:c25:bc19:2d25/1282c19:dd:d9:dd:c25:c25:bc19:2d25
392c19:dd:d9:dd:c25:c25:bc19:2d26/1282c19:dd:d9:dd:c25:c25:bc19:2d26
402c19:dd:d9:dd:c25:c25:bc19:2d27/1282c19:dd:d9:dd:c25:c25:bc19:2d27
412c19:dd:d9:dd:c25:c25:bc19:2d28/1282c19:dd:d9:dd:c25:c25:bc19:2d28
422c19:dd:d9:dd:c25:c25:bc19:2d29/1282c19:dd:d9:dd:c25:c25:bc19:2d29
432c19:dd:d9:dd:c25:c25:bc19:2d2a/1282c19:dd:d9:dd:c25:c25:bc19:2d2a
442c19:dd:d9:dd:c25:c25:bc19:2d2b/1282c19:dd:d9:dd:c25:c25:bc19:2d2b
452c19:dd:d9:dd:c25:c25:bc19:2d2c/1282c19:dd:d9:dd:c25:c25:bc19:2d2c
462c19:dd:d9:dd:c25:c25:bc19:2d2d/1282c19:dd:d9:dd:c25:c25:bc19:2d2d
472c19:dd:d9:dd:c25:c25:bc19:2d2e/1282c19:dd:d9:dd:c25:c25:bc19:2d2e
482c19:dd:d9:dd:c25:c25:bc19:2d2f/1282c19:dd:d9:dd:c25:c25:bc19:2d2f
492c19:dd:d9:dd:c25:c25:bc19:2d30/1282c19:dd:d9:dd:c25:c25:bc19:2d30
502c19:dd:d9:dd:c25:c25:bc19:2d31/1282c19:dd:d9:dd:c25:c25:bc19:2d31
512c19:dd:d9:dd:c25:c25:bc19:2d32/1282c19:dd:d9:dd:c25:c25:bc19:2d32
522c19:dd:d9:dd:c25:c25:bc19:2d33/1282c19:dd:d9:dd:c25:c25:bc19:2d33
532c19:dd:d9:dd:c25:c25:bc19:2d34/1282c19:dd:d9:dd:c25:c25:bc19:2d34
542c19:dd:d9:dd:c25:c25:bc19:2d35/1282c19:dd:d9:dd:c25:c25:bc19:2d35
552c19:dd:d9:dd:c25:c25:bc19:2d36/1282c19:dd:d9:dd:c25:c25:bc19:2d36
562c19:dd:d9:dd:c25:c25:bc19:2d37/1282c19:dd:d9:dd:c25:c25:bc19:2d37
572c19:dd:d9:dd:c25:c25:bc19:2d38/1282c19:dd:d9:dd:c25:c25:bc19:2d38
582c19:dd:d9:dd:c25:c25:bc19:2d39/1282c19:dd:d9:dd:c25:c25:bc19:2d39
592c19:dd:d9:dd:c25:c25:bc19:2d3a/1282c19:dd:d9:dd:c25:c25:bc19:2d3a
602c19:dd:d9:dd:c25:c25:bc19:2d3b/1282c19:dd:d9:dd:c25:c25:bc19:2d3b
612c19:dd:d9:dd:c25:c25:bc19:2d3c/1282c19:dd:d9:dd:c25:c25:bc19:2d3c
622c19:dd:d9:dd:c25:c25:bc19:2d3d/1282c19:dd:d9:dd:c25:c25:bc19:2d3d
632c19:dd:d9:dd:c25:c25:bc19:2d3e/1282c19:dd:d9:dd:c25:c25:bc19:2d3e
642c19:dd:d9:dd:c25:c25:bc19:2d3f/1282c19:dd:d9:dd:c25:c25:bc19:2d3f
652c19:dd:d9:dd:c25:c25:bc19:2d40/1282c19:dd:d9:dd:c25:c25:bc19:2d40
662c19:dd:d9:dd:c25:c25:bc19:2d41/1282c19:dd:d9:dd:c25:c25:bc19:2d41
672c19:dd:d9:dd:c25:c25:bc19:2d42/1282c19:dd:d9:dd:c25:c25:bc19:2d42
682c19:dd:d9:dd:c25:c25:bc19:2d43/1282c19:dd:d9:dd:c25:c25:bc19:2d43
692c19:dd:d9:dd:c25:c25:bc19:2d44/1282c19:dd:d9:dd:c25:c25:bc19:2d44
702c19:dd:d9:dd:c25:c25:bc19:2d45/1282c19:dd:d9:dd:c25:c25:bc19:2d45
712c19:dd:d9:dd:c25:c25:bc19:2d46/1282c19:dd:d9:dd:c25:c25:bc19:2d46
722c19:dd:d9:dd:c25:c25:bc19:2d47/1282c19:dd:d9:dd:c25:c25:bc19:2d47
732c19:dd:d9:dd:c25:c25:bc19:2d48/1282c19:dd:d9:dd:c25:c25:bc19:2d48
742c19:dd:d9:dd:c25:c25:bc19:2d49/1282c19:dd:d9:dd:c25:c25:bc19:2d49
752c19:dd:d9:dd:c25:c25:bc19:2d4a/1282c19:dd:d9:dd:c25:c25:bc19:2d4a
762c19:dd:d9:dd:c25:c25:bc19:2d4b/1282c19:dd:d9:dd:c25:c25:bc19:2d4b
772c19:dd:d9:dd:c25:c25:bc19:2d4c/1282c19:dd:d9:dd:c25:c25:bc19:2d4c
782c19:dd:d9:dd:c25:c25:bc19:2d4d/1282c19:dd:d9:dd:c25:c25:bc19:2d4d
792c19:dd:d9:dd:c25:c25:bc19:2d4e/1282c19:dd:d9:dd:c25:c25:bc19:2d4e
802c19:dd:d9:dd:c25:c25:bc19:2d4f/1282c19:dd:d9:dd:c25:c25:bc19:2d4f
812c19:dd:d9:dd:c25:c25:bc19:2d50/1282c19:dd:d9:dd:c25:c25:bc19:2d50
822c19:dd:d9:dd:c25:c25:bc19:2d51/1282c19:dd:d9:dd:c25:c25:bc19:2d51
832c19:dd:d9:dd:c25:c25:bc19:2d52/1282c19:dd:d9:dd:c25:c25:bc19:2d52
842c19:dd:d9:dd:c25:c25:bc19:2d53/1282c19:dd:d9:dd:c25:c25:bc19:2d53
852c19:dd:d9:dd:c25:c25:bc19:2d54/1282c19:dd:d9:dd:c25:c25:bc19:2d54
862c19:dd:d9:dd:c25:c25:bc19:2d55/1282c19:dd:d9:dd:c25:c25:bc19:2d55
872c19:dd:d9:dd:c25:c25:bc19:2d56/1282c19:dd:d9:dd:c25:c25:bc19:2d56
882c19:dd:d9:dd:c25:c25:bc19:2d57/1282c19:dd:d9:dd:c25:c25:bc19:2d57
892c19:dd:d9:dd:c25:c25:bc19:2d58/1282c19:dd:d9:dd:c25:c25:bc19:2d58
902c19:dd:d9:dd:c25:c25:bc19:2d59/1282c19:dd:d9:dd:c25:c25:bc19:2d59
912c19:dd:d9:dd:c25:c25:bc19:2d5a/1282c19:dd:d9:dd:c25:c25:bc19:2d5a
922c19:dd:d9:dd:c25:c25:bc19:2d5b/1282c19:dd:d9:dd:c25:c25:bc19:2d5b
932c19:dd:d9:dd:c25:c25:bc19:2d5c/1282c19:dd:d9:dd:c25:c25:bc19:2d5c
942c19:dd:d9:dd:c25:c25:bc19:2d5d/1282c19:dd:d9:dd:c25:c25:bc19:2d5d
952c19:dd:d9:dd:c25:c25:bc19:2d5e/1282c19:dd:d9:dd:c25:c25:bc19:2d5e
962c19:dd:d9:dd:c25:c25:bc19:2d5f/1282c19:dd:d9:dd:c25:c25:bc19:2d5f
972c19:dd:d9:dd:c25:c25:bc19:2d60/1282c19:dd:d9:dd:c25:c25:bc19:2d60
982c19:dd:d9:dd:c25:c25:bc19:2d61/1282c19:dd:d9:dd:c25:c25:bc19:2d61
992c19:dd:d9:dd:c25:c25:bc19:2d62/1282c19:dd:d9:dd:c25:c25:bc19:2d62
1002c19:dd:d9:dd:c25:c25:bc19:2d63/1282c19:dd:d9:dd:c25:c25:bc19:2d63
1012c19:dd:d9:dd:c25:c25:bc19:2d64/1282c19:dd:d9:dd:c25:c25:bc19:2d64
1022c19:dd:d9:dd:c25:c25:bc19:2d65/1282c19:dd:d9:dd:c25:c25:bc19:2d65
1032c19:dd:d9:dd:c25:c25:bc19:2d66/1282c19:dd:d9:dd:c25:c25:bc19:2d66
1042c19:dd:d9:dd:c25:c25:bc19:2d67/1282c19:dd:d9:dd:c25:c25:bc19:2d67
1052c19:dd:d9:dd:c25:c25:bc19:2d68/1282c19:dd:d9:dd:c25:c25:bc19:2d68
1062c19:dd:d9:dd:c25:c25:bc19:2d69/1282c19:dd:d9:dd:c25:c25:bc19:2d69
1072c19:dd:d9:dd:c25:c25:bc19:2d6a/1282c19:dd:d9:dd:c25:c25:bc19:2d6a
1082c19:dd:d9:dd:c25:c25:bc19:2d6b/1282c19:dd:d9:dd:c25:c25:bc19:2d6b
1092c19:dd:d9:dd:c25:c25:bc19:2d6c/1282c19:dd:d9:dd:c25:c25:bc19:2d6c
1102c19:dd:d9:dd:c25:c25:bc19:2d6d/1282c19:dd:d9:dd:c25:c25:bc19:2d6d
1112c19:dd:d9:dd:c25:c25:bc19:2d6e/1282c19:dd:d9:dd:c25:c25:bc19:2d6e
1122c19:dd:d9:dd:c25:c25:bc19:2d6f/1282c19:dd:d9:dd:c25:c25:bc19:2d6f
1132c19:dd:d9:dd:c25:c25:bc19:2d70/1282c19:dd:d9:dd:c25:c25:bc19:2d70
1142c19:dd:d9:dd:c25:c25:bc19:2d71/1282c19:dd:d9:dd:c25:c25:bc19:2d71
1152c19:dd:d9:dd:c25:c25:bc19:2d72/1282c19:dd:d9:dd:c25:c25:bc19:2d72
1162c19:dd:d9:dd:c25:c25:bc19:2d73/1282c19:dd:d9:dd:c25:c25:bc19:2d73
1172c19:dd:d9:dd:c25:c25:bc19:2d74/1282c19:dd:d9:dd:c25:c25:bc19:2d74
1182c19:dd:d9:dd:c25:c25:bc19:2d75/1282c19:dd:d9:dd:c25:c25:bc19:2d75
1192c19:dd:d9:dd:c25:c25:bc19:2d76/1282c19:dd:d9:dd:c25:c25:bc19:2d76
1202c19:dd:d9:dd:c25:c25:bc19:2d77/1282c19:dd:d9:dd:c25:c25:bc19:2d77
1212c19:dd:d9:dd:c25:c25:bc19:2d78/1282c19:dd:d9:dd:c25:c25:bc19:2d78
1222c19:dd:d9:dd:c25:c25:bc19:2d79/1282c19:dd:d9:dd:c25:c25:bc19:2d79
1232c19:dd:d9:dd:c25:c25:bc19:2d7a/1282c19:dd:d9:dd:c25:c25:bc19:2d7a
1242c19:dd:d9:dd:c25:c25:bc19:2d7b/1282c19:dd:d9:dd:c25:c25:bc19:2d7b
1252c19:dd:d9:dd:c25:c25:bc19:2d7c/1282c19:dd:d9:dd:c25:c25:bc19:2d7c
1262c19:dd:d9:dd:c25:c25:bc19:2d7d/1282c19:dd:d9:dd:c25:c25:bc19:2d7d
1272c19:dd:d9:dd:c25:c25:bc19:2d7e/1282c19:dd:d9:dd:c25:c25:bc19:2d7e
1282c19:dd:d9:dd:c25:c25:bc19:2d7f/1282c19:dd:d9:dd:c25:c25:bc19:2d7f
1292c19:dd:d9:dd:c25:c25:bc19:2d80/1282c19:dd:d9:dd:c25:c25:bc19:2d80
1302c19:dd:d9:dd:c25:c25:bc19:2d81/1282c19:dd:d9:dd:c25:c25:bc19:2d81
1312c19:dd:d9:dd:c25:c25:bc19:2d82/1282c19:dd:d9:dd:c25:c25:bc19:2d82
1322c19:dd:d9:dd:c25:c25:bc19:2d83/1282c19:dd:d9:dd:c25:c25:bc19:2d83
1332c19:dd:d9:dd:c25:c25:bc19:2d84/1282c19:dd:d9:dd:c25:c25:bc19:2d84
1342c19:dd:d9:dd:c25:c25:bc19:2d85/1282c19:dd:d9:dd:c25:c25:bc19:2d85
1352c19:dd:d9:dd:c25:c25:bc19:2d86/1282c19:dd:d9:dd:c25:c25:bc19:2d86
1362c19:dd:d9:dd:c25:c25:bc19:2d87/1282c19:dd:d9:dd:c25:c25:bc19:2d87
1372c19:dd:d9:dd:c25:c25:bc19:2d88/1282c19:dd:d9:dd:c25:c25:bc19:2d88
1382c19:dd:d9:dd:c25:c25:bc19:2d89/1282c19:dd:d9:dd:c25:c25:bc19:2d89
1392c19:dd:d9:dd:c25:c25:bc19:2d8a/1282c19:dd:d9:dd:c25:c25:bc19:2d8a
1402c19:dd:d9:dd:c25:c25:bc19:2d8b/1282c19:dd:d9:dd:c25:c25:bc19:2d8b
1412c19:dd:d9:dd:c25:c25:bc19:2d8c/1282c19:dd:d9:dd:c25:c25:bc19:2d8c
1422c19:dd:d9:dd:c25:c25:bc19:2d8d/1282c19:dd:d9:dd:c25:c25:bc19:2d8d
1432c19:dd:d9:dd:c25:c25:bc19:2d8e/1282c19:dd:d9:dd:c25:c25:bc19:2d8e
1442c19:dd:d9:dd:c25:c25:bc19:2d8f/1282c19:dd:d9:dd:c25:c25:bc19:2d8f
1452c19:dd:d9:dd:c25:c25:bc19:2d90/1282c19:dd:d9:dd:c25:c25:bc19:2d90
1462c19:dd:d9:dd:c25:c25:bc19:2d91/1282c19:dd:d9:dd:c25:c25:bc19:2d91
1472c19:dd:d9:dd:c25:c25:bc19:2d92/1282c19:dd:d9:dd:c25:c25:bc19:2d92
1482c19:dd:d9:dd:c25:c25:bc19:2d93/1282c19:dd:d9:dd:c25:c25:bc19:2d93
1492c19:dd:d9:dd:c25:c25:bc19:2d94/1282c19:dd:d9:dd:c25:c25:bc19:2d94
1502c19:dd:d9:dd:c25:c25:bc19:2d95/1282c19:dd:d9:dd:c25:c25:bc19:2d95
1512c19:dd:d9:dd:c25:c25:bc19:2d96/1282c19:dd:d9:dd:c25:c25:bc19:2d96
1522c19:dd:d9:dd:c25:c25:bc19:2d97/1282c19:dd:d9:dd:c25:c25:bc19:2d97
1532c19:dd:d9:dd:c25:c25:bc19:2d98/1282c19:dd:d9:dd:c25:c25:bc19:2d98
1542c19:dd:d9:dd:c25:c25:bc19:2d99/1282c19:dd:d9:dd:c25:c25:bc19:2d99
1552c19:dd:d9:dd:c25:c25:bc19:2d9a/1282c19:dd:d9:dd:c25:c25:bc19:2d9a
1562c19:dd:d9:dd:c25:c25:bc19:2d9b/1282c19:dd:d9:dd:c25:c25:bc19:2d9b
1572c19:dd:d9:dd:c25:c25:bc19:2d9c/1282c19:dd:d9:dd:c25:c25:bc19:2d9c
1582c19:dd:d9:dd:c25:c25:bc19:2d9d/1282c19:dd:d9:dd:c25:c25:bc19:2d9d
1592c19:dd:d9:dd:c25:c25:bc19:2d9e/1282c19:dd:d9:dd:c25:c25:bc19:2d9e
1602c19:dd:d9:dd:c25:c25:bc19:2d9f/1282c19:dd:d9:dd:c25:c25:bc19:2d9f
1612c19:dd:d9:dd:c25:c25:bc19:2da0/1282c19:dd:d9:dd:c25:c25:bc19:2da0
1622c19:dd:d9:dd:c25:c25:bc19:2da1/1282c19:dd:d9:dd:c25:c25:bc19:2da1
1632c19:dd:d9:dd:c25:c25:bc19:2da2/1282c19:dd:d9:dd:c25:c25:bc19:2da2
1642c19:dd:d9:dd:c25:c25:bc19:2da3/1282c19:dd:d9:dd:c25:c25:bc19:2da3
1652c19:dd:d9:dd:c25:c25:bc19:2da4/1282c19:dd:d9:dd:c25:c25:bc19:2da4
1662c19:dd:d9:dd:c25:c25:bc19:2da5/1282c19:dd:d9:dd:c25:c25:bc19:2da5
1672c19:dd:d9:dd:c25:c25:bc19:2da6/1282c19:dd:d9:dd:c25:c25:bc19:2da6
1682c19:dd:d9:dd:c25:c25:bc19:2da7/1282c19:dd:d9:dd:c25:c25:bc19:2da7
1692c19:dd:d9:dd:c25:c25:bc19:2da8/1282c19:dd:d9:dd:c25:c25:bc19:2da8
1702c19:dd:d9:dd:c25:c25:bc19:2da9/1282c19:dd:d9:dd:c25:c25:bc19:2da9
1712c19:dd:d9:dd:c25:c25:bc19:2daa/1282c19:dd:d9:dd:c25:c25:bc19:2daa
1722c19:dd:d9:dd:c25:c25:bc19:2dab/1282c19:dd:d9:dd:c25:c25:bc19:2dab
1732c19:dd:d9:dd:c25:c25:bc19:2dac/1282c19:dd:d9:dd:c25:c25:bc19:2dac
1742c19:dd:d9:dd:c25:c25:bc19:2dad/1282c19:dd:d9:dd:c25:c25:bc19:2dad
1752c19:dd:d9:dd:c25:c25:bc19:2dae/1282c19:dd:d9:dd:c25:c25:bc19:2dae
1762c19:dd:d9:dd:c25:c25:bc19:2daf/1282c19:dd:d9:dd:c25:c25:bc19:2daf
1772c19:dd:d9:dd:c25:c25:bc19:2db0/1282c19:dd:d9:dd:c25:c25:bc19:2db0
1782c19:dd:d9:dd:c25:c25:bc19:2db1/1282c19:dd:d9:dd:c25:c25:bc19:2db1
1792c19:dd:d9:dd:c25:c25:bc19:2db2/1282c19:dd:d9:dd:c25:c25:bc19:2db2
1802c19:dd:d9:dd:c25:c25:bc19:2db3/1282c19:dd:d9:dd:c25:c25:bc19:2db3
1812c19:dd:d9:dd:c25:c25:bc19:2db4/1282c19:dd:d9:dd:c25:c25:bc19:2db4
1822c19:dd:d9:dd:c25:c25:bc19:2db5/1282c19:dd:d9:dd:c25:c25:bc19:2db5
1832c19:dd:d9:dd:c25:c25:bc19:2db6/1282c19:dd:d9:dd:c25:c25:bc19:2db6
1842c19:dd:d9:dd:c25:c25:bc19:2db7/1282c19:dd:d9:dd:c25:c25:bc19:2db7
1852c19:dd:d9:dd:c25:c25:bc19:2db8/1282c19:dd:d9:dd:c25:c25:bc19:2db8
1862c19:dd:d9:dd:c25:c25:bc19:2db9/1282c19:dd:d9:dd:c25:c25:bc19:2db9
1872c19:dd:d9:dd:c25:c25:bc19:2dba/1282c19:dd:d9:dd:c25:c25:bc19:2dba
1882c19:dd:d9:dd:c25:c25:bc19:2dbb/1282c19:dd:d9:dd:c25:c25:bc19:2dbb
1892c19:dd:d9:dd:c25:c25:bc19:2dbc/1282c19:dd:d9:dd:c25:c25:bc19:2dbc
1902c19:dd:d9:dd:c25:c25:bc19:2dbd/1282c19:dd:d9:dd:c25:c25:bc19:2dbd
1912c19:dd:d9:dd:c25:c25:bc19:2dbe/1282c19:dd:d9:dd:c25:c25:bc19:2dbe
1922c19:dd:d9:dd:c25:c25:bc19:2dbf/1282c19:dd:d9:dd:c25:c25:bc19:2dbf
1932c19:dd:d9:dd:c25:c25:bc19:2dc0/1282c19:dd:d9:dd:c25:c25:bc19:2dc0
1942c19:dd:d9:dd:c25:c25:bc19:2dc1/1282c19:dd:d9:dd:c25:c25:bc19:2dc1
1952c19:dd:d9:dd:c25:c25:bc19:2dc2/1282c19:dd:d9:dd:c25:c25:bc19:2dc2
1962c19:dd:d9:dd:c25:c25:bc19:2dc3/1282c19:dd:d9:dd:c25:c25:bc19:2dc3
1972c19:dd:d9:dd:c25:c25:bc19:2dc4/1282c19:dd:d9:dd:c25:c25:bc19:2dc4
1982c19:dd:d9:dd:c25:c25:bc19:2dc5/1282c19:dd:d9:dd:c25:c25:bc19:2dc5
1992c19:dd:d9:dd:c25:c25:bc19:2dc6/1282c19:dd:d9:dd:c25:c25:bc19:2dc6
2002c19:dd:d9:dd:c25:c25:bc19:2dc7/1282c19:dd:d9:dd:c25:c25:bc19:2dc7
2012c19:dd:d9:dd:c25:c25:bc19:2dc8/1282c19:dd:d9:dd:c25:c25:bc19:2dc8
2022c19:dd:d9:dd:c25:c25:bc19:2dc9/1282c19:dd:d9:dd:c25:c25:bc19:2dc9
2032c19:dd:d9:dd:c25:c25:bc19:2dca/1282c19:dd:d9:dd:c25:c25:bc19:2dca
2042c19:dd:d9:dd:c25:c25:bc19:2dcb/1282c19:dd:d9:dd:c25:c25:bc19:2dcb
2052c19:dd:d9:dd:c25:c25:bc19:2dcc/1282c19:dd:d9:dd:c25:c25:bc19:2dcc
2062c19:dd:d9:dd:c25:c25:bc19:2dcd/1282c19:dd:d9:dd:c25:c25:bc19:2dcd
2072c19:dd:d9:dd:c25:c25:bc19:2dce/1282c19:dd:d9:dd:c25:c25:bc19:2dce
2082c19:dd:d9:dd:c25:c25:bc19:2dcf/1282c19:dd:d9:dd:c25:c25:bc19:2dcf
2092c19:dd:d9:dd:c25:c25:bc19:2dd0/1282c19:dd:d9:dd:c25:c25:bc19:2dd0
2102c19:dd:d9:dd:c25:c25:bc19:2dd1/1282c19:dd:d9:dd:c25:c25:bc19:2dd1
2112c19:dd:d9:dd:c25:c25:bc19:2dd2/1282c19:dd:d9:dd:c25:c25:bc19:2dd2
2122c19:dd:d9:dd:c25:c25:bc19:2dd3/1282c19:dd:d9:dd:c25:c25:bc19:2dd3
2132c19:dd:d9:dd:c25:c25:bc19:2dd4/1282c19:dd:d9:dd:c25:c25:bc19:2dd4
2142c19:dd:d9:dd:c25:c25:bc19:2dd5/1282c19:dd:d9:dd:c25:c25:bc19:2dd5
2152c19:dd:d9:dd:c25:c25:bc19:2dd6/1282c19:dd:d9:dd:c25:c25:bc19:2dd6
2162c19:dd:d9:dd:c25:c25:bc19:2dd7/1282c19:dd:d9:dd:c25:c25:bc19:2dd7
2172c19:dd:d9:dd:c25:c25:bc19:2dd8/1282c19:dd:d9:dd:c25:c25:bc19:2dd8
2182c19:dd:d9:dd:c25:c25:bc19:2dd9/1282c19:dd:d9:dd:c25:c25:bc19:2dd9
2192c19:dd:d9:dd:c25:c25:bc19:2dda/1282c19:dd:d9:dd:c25:c25:bc19:2dda
2202c19:dd:d9:dd:c25:c25:bc19:2ddb/1282c19:dd:d9:dd:c25:c25:bc19:2ddb
2212c19:dd:d9:dd:c25:c25:bc19:2ddc/1282c19:dd:d9:dd:c25:c25:bc19:2ddc
2222c19:dd:d9:dd:c25:c25:bc19:2ddd/1282c19:dd:d9:dd:c25:c25:bc19:2ddd
2232c19:dd:d9:dd:c25:c25:bc19:2dde/1282c19:dd:d9:dd:c25:c25:bc19:2dde
2242c19:dd:d9:dd:c25:c25:bc19:2ddf/1282c19:dd:d9:dd:c25:c25:bc19:2ddf
2252c19:dd:d9:dd:c25:c25:bc19:2de0/1282c19:dd:d9:dd:c25:c25:bc19:2de0
2262c19:dd:d9:dd:c25:c25:bc19:2de1/1282c19:dd:d9:dd:c25:c25:bc19:2de1
2272c19:dd:d9:dd:c25:c25:bc19:2de2/1282c19:dd:d9:dd:c25:c25:bc19:2de2
2282c19:dd:d9:dd:c25:c25:bc19:2de3/1282c19:dd:d9:dd:c25:c25:bc19:2de3
2292c19:dd:d9:dd:c25:c25:bc19:2de4/1282c19:dd:d9:dd:c25:c25:bc19:2de4
2302c19:dd:d9:dd:c25:c25:bc19:2de5/1282c19:dd:d9:dd:c25:c25:bc19:2de5
2312c19:dd:d9:dd:c25:c25:bc19:2de6/1282c19:dd:d9:dd:c25:c25:bc19:2de6
2322c19:dd:d9:dd:c25:c25:bc19:2de7/1282c19:dd:d9:dd:c25:c25:bc19:2de7
2332c19:dd:d9:dd:c25:c25:bc19:2de8/1282c19:dd:d9:dd:c25:c25:bc19:2de8
2342c19:dd:d9:dd:c25:c25:bc19:2de9/1282c19:dd:d9:dd:c25:c25:bc19:2de9
2352c19:dd:d9:dd:c25:c25:bc19:2dea/1282c19:dd:d9:dd:c25:c25:bc19:2dea
2362c19:dd:d9:dd:c25:c25:bc19:2deb/1282c19:dd:d9:dd:c25:c25:bc19:2deb
2372c19:dd:d9:dd:c25:c25:bc19:2dec/1282c19:dd:d9:dd:c25:c25:bc19:2dec
2382c19:dd:d9:dd:c25:c25:bc19:2ded/1282c19:dd:d9:dd:c25:c25:bc19:2ded
2392c19:dd:d9:dd:c25:c25:bc19:2dee/1282c19:dd:d9:dd:c25:c25:bc19:2dee
2402c19:dd:d9:dd:c25:c25:bc19:2def/1282c19:dd:d9:dd:c25:c25:bc19:2def
2412c19:dd:d9:dd:c25:c25:bc19:2df0/1282c19:dd:d9:dd:c25:c25:bc19:2df0
2422c19:dd:d9:dd:c25:c25:bc19:2df1/1282c19:dd:d9:dd:c25:c25:bc19:2df1
2432c19:dd:d9:dd:c25:c25:bc19:2df2/1282c19:dd:d9:dd:c25:c25:bc19:2df2
2442c19:dd:d9:dd:c25:c25:bc19:2df3/1282c19:dd:d9:dd:c25:c25:bc19:2df3
2452c19:dd:d9:dd:c25:c25:bc19:2df4/1282c19:dd:d9:dd:c25:c25:bc19:2df4
2462c19:dd:d9:dd:c25:c25:bc19:2df5/1282c19:dd:d9:dd:c25:c25:bc19:2df5
2472c19:dd:d9:dd:c25:c25:bc19:2df6/1282c19:dd:d9:dd:c25:c25:bc19:2df6
2482c19:dd:d9:dd:c25:c25:bc19:2df7/1282c19:dd:d9:dd:c25:c25:bc19:2df7
2492c19:dd:d9:dd:c25:c25:bc19:2df8/1282c19:dd:d9:dd:c25:c25:bc19:2df8
2502c19:dd:d9:dd:c25:c25:bc19:2df9/1282c19:dd:d9:dd:c25:c25:bc19:2df9
2512c19:dd:d9:dd:c25:c25:bc19:2dfa/1282c19:dd:d9:dd:c25:c25:bc19:2dfa
2522c19:dd:d9:dd:c25:c25:bc19:2dfb/1282c19:dd:d9:dd:c25:c25:bc19:2dfb
2532c19:dd:d9:dd:c25:c25:bc19:2dfc/1282c19:dd:d9:dd:c25:c25:bc19:2dfc
2542c19:dd:d9:dd:c25:c25:bc19:2dfd/1282c19:dd:d9:dd:c25:c25:bc19:2dfd
2552c19:dd:d9:dd:c25:c25:bc19:2dfe/1282c19:dd:d9:dd:c25:c25:bc19:2dfe
2562c19:dd:d9:dd:c25:c25:bc19:2dff/1282c19:dd:d9:dd:c25:c25:bc19:2dff

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.