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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:9e00/120
First address
2c19:dd:d9:dd:c25:c25:94de:9e00
Last address
2c19:dd:d9:dd:c25:c25:94de:9eff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:9e00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.9.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:9e00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:9e00/1282c19:dd:d9:dd:c25:c25:94de:9e00
22c19:dd:d9:dd:c25:c25:94de:9e01/1282c19:dd:d9:dd:c25:c25:94de:9e01
32c19:dd:d9:dd:c25:c25:94de:9e02/1282c19:dd:d9:dd:c25:c25:94de:9e02
42c19:dd:d9:dd:c25:c25:94de:9e03/1282c19:dd:d9:dd:c25:c25:94de:9e03
52c19:dd:d9:dd:c25:c25:94de:9e04/1282c19:dd:d9:dd:c25:c25:94de:9e04
62c19:dd:d9:dd:c25:c25:94de:9e05/1282c19:dd:d9:dd:c25:c25:94de:9e05
72c19:dd:d9:dd:c25:c25:94de:9e06/1282c19:dd:d9:dd:c25:c25:94de:9e06
82c19:dd:d9:dd:c25:c25:94de:9e07/1282c19:dd:d9:dd:c25:c25:94de:9e07
92c19:dd:d9:dd:c25:c25:94de:9e08/1282c19:dd:d9:dd:c25:c25:94de:9e08
102c19:dd:d9:dd:c25:c25:94de:9e09/1282c19:dd:d9:dd:c25:c25:94de:9e09
112c19:dd:d9:dd:c25:c25:94de:9e0a/1282c19:dd:d9:dd:c25:c25:94de:9e0a
122c19:dd:d9:dd:c25:c25:94de:9e0b/1282c19:dd:d9:dd:c25:c25:94de:9e0b
132c19:dd:d9:dd:c25:c25:94de:9e0c/1282c19:dd:d9:dd:c25:c25:94de:9e0c
142c19:dd:d9:dd:c25:c25:94de:9e0d/1282c19:dd:d9:dd:c25:c25:94de:9e0d
152c19:dd:d9:dd:c25:c25:94de:9e0e/1282c19:dd:d9:dd:c25:c25:94de:9e0e
162c19:dd:d9:dd:c25:c25:94de:9e0f/1282c19:dd:d9:dd:c25:c25:94de:9e0f
172c19:dd:d9:dd:c25:c25:94de:9e10/1282c19:dd:d9:dd:c25:c25:94de:9e10
182c19:dd:d9:dd:c25:c25:94de:9e11/1282c19:dd:d9:dd:c25:c25:94de:9e11
192c19:dd:d9:dd:c25:c25:94de:9e12/1282c19:dd:d9:dd:c25:c25:94de:9e12
202c19:dd:d9:dd:c25:c25:94de:9e13/1282c19:dd:d9:dd:c25:c25:94de:9e13
212c19:dd:d9:dd:c25:c25:94de:9e14/1282c19:dd:d9:dd:c25:c25:94de:9e14
222c19:dd:d9:dd:c25:c25:94de:9e15/1282c19:dd:d9:dd:c25:c25:94de:9e15
232c19:dd:d9:dd:c25:c25:94de:9e16/1282c19:dd:d9:dd:c25:c25:94de:9e16
242c19:dd:d9:dd:c25:c25:94de:9e17/1282c19:dd:d9:dd:c25:c25:94de:9e17
252c19:dd:d9:dd:c25:c25:94de:9e18/1282c19:dd:d9:dd:c25:c25:94de:9e18
262c19:dd:d9:dd:c25:c25:94de:9e19/1282c19:dd:d9:dd:c25:c25:94de:9e19
272c19:dd:d9:dd:c25:c25:94de:9e1a/1282c19:dd:d9:dd:c25:c25:94de:9e1a
282c19:dd:d9:dd:c25:c25:94de:9e1b/1282c19:dd:d9:dd:c25:c25:94de:9e1b
292c19:dd:d9:dd:c25:c25:94de:9e1c/1282c19:dd:d9:dd:c25:c25:94de:9e1c
302c19:dd:d9:dd:c25:c25:94de:9e1d/1282c19:dd:d9:dd:c25:c25:94de:9e1d
312c19:dd:d9:dd:c25:c25:94de:9e1e/1282c19:dd:d9:dd:c25:c25:94de:9e1e
322c19:dd:d9:dd:c25:c25:94de:9e1f/1282c19:dd:d9:dd:c25:c25:94de:9e1f
332c19:dd:d9:dd:c25:c25:94de:9e20/1282c19:dd:d9:dd:c25:c25:94de:9e20
342c19:dd:d9:dd:c25:c25:94de:9e21/1282c19:dd:d9:dd:c25:c25:94de:9e21
352c19:dd:d9:dd:c25:c25:94de:9e22/1282c19:dd:d9:dd:c25:c25:94de:9e22
362c19:dd:d9:dd:c25:c25:94de:9e23/1282c19:dd:d9:dd:c25:c25:94de:9e23
372c19:dd:d9:dd:c25:c25:94de:9e24/1282c19:dd:d9:dd:c25:c25:94de:9e24
382c19:dd:d9:dd:c25:c25:94de:9e25/1282c19:dd:d9:dd:c25:c25:94de:9e25
392c19:dd:d9:dd:c25:c25:94de:9e26/1282c19:dd:d9:dd:c25:c25:94de:9e26
402c19:dd:d9:dd:c25:c25:94de:9e27/1282c19:dd:d9:dd:c25:c25:94de:9e27
412c19:dd:d9:dd:c25:c25:94de:9e28/1282c19:dd:d9:dd:c25:c25:94de:9e28
422c19:dd:d9:dd:c25:c25:94de:9e29/1282c19:dd:d9:dd:c25:c25:94de:9e29
432c19:dd:d9:dd:c25:c25:94de:9e2a/1282c19:dd:d9:dd:c25:c25:94de:9e2a
442c19:dd:d9:dd:c25:c25:94de:9e2b/1282c19:dd:d9:dd:c25:c25:94de:9e2b
452c19:dd:d9:dd:c25:c25:94de:9e2c/1282c19:dd:d9:dd:c25:c25:94de:9e2c
462c19:dd:d9:dd:c25:c25:94de:9e2d/1282c19:dd:d9:dd:c25:c25:94de:9e2d
472c19:dd:d9:dd:c25:c25:94de:9e2e/1282c19:dd:d9:dd:c25:c25:94de:9e2e
482c19:dd:d9:dd:c25:c25:94de:9e2f/1282c19:dd:d9:dd:c25:c25:94de:9e2f
492c19:dd:d9:dd:c25:c25:94de:9e30/1282c19:dd:d9:dd:c25:c25:94de:9e30
502c19:dd:d9:dd:c25:c25:94de:9e31/1282c19:dd:d9:dd:c25:c25:94de:9e31
512c19:dd:d9:dd:c25:c25:94de:9e32/1282c19:dd:d9:dd:c25:c25:94de:9e32
522c19:dd:d9:dd:c25:c25:94de:9e33/1282c19:dd:d9:dd:c25:c25:94de:9e33
532c19:dd:d9:dd:c25:c25:94de:9e34/1282c19:dd:d9:dd:c25:c25:94de:9e34
542c19:dd:d9:dd:c25:c25:94de:9e35/1282c19:dd:d9:dd:c25:c25:94de:9e35
552c19:dd:d9:dd:c25:c25:94de:9e36/1282c19:dd:d9:dd:c25:c25:94de:9e36
562c19:dd:d9:dd:c25:c25:94de:9e37/1282c19:dd:d9:dd:c25:c25:94de:9e37
572c19:dd:d9:dd:c25:c25:94de:9e38/1282c19:dd:d9:dd:c25:c25:94de:9e38
582c19:dd:d9:dd:c25:c25:94de:9e39/1282c19:dd:d9:dd:c25:c25:94de:9e39
592c19:dd:d9:dd:c25:c25:94de:9e3a/1282c19:dd:d9:dd:c25:c25:94de:9e3a
602c19:dd:d9:dd:c25:c25:94de:9e3b/1282c19:dd:d9:dd:c25:c25:94de:9e3b
612c19:dd:d9:dd:c25:c25:94de:9e3c/1282c19:dd:d9:dd:c25:c25:94de:9e3c
622c19:dd:d9:dd:c25:c25:94de:9e3d/1282c19:dd:d9:dd:c25:c25:94de:9e3d
632c19:dd:d9:dd:c25:c25:94de:9e3e/1282c19:dd:d9:dd:c25:c25:94de:9e3e
642c19:dd:d9:dd:c25:c25:94de:9e3f/1282c19:dd:d9:dd:c25:c25:94de:9e3f
652c19:dd:d9:dd:c25:c25:94de:9e40/1282c19:dd:d9:dd:c25:c25:94de:9e40
662c19:dd:d9:dd:c25:c25:94de:9e41/1282c19:dd:d9:dd:c25:c25:94de:9e41
672c19:dd:d9:dd:c25:c25:94de:9e42/1282c19:dd:d9:dd:c25:c25:94de:9e42
682c19:dd:d9:dd:c25:c25:94de:9e43/1282c19:dd:d9:dd:c25:c25:94de:9e43
692c19:dd:d9:dd:c25:c25:94de:9e44/1282c19:dd:d9:dd:c25:c25:94de:9e44
702c19:dd:d9:dd:c25:c25:94de:9e45/1282c19:dd:d9:dd:c25:c25:94de:9e45
712c19:dd:d9:dd:c25:c25:94de:9e46/1282c19:dd:d9:dd:c25:c25:94de:9e46
722c19:dd:d9:dd:c25:c25:94de:9e47/1282c19:dd:d9:dd:c25:c25:94de:9e47
732c19:dd:d9:dd:c25:c25:94de:9e48/1282c19:dd:d9:dd:c25:c25:94de:9e48
742c19:dd:d9:dd:c25:c25:94de:9e49/1282c19:dd:d9:dd:c25:c25:94de:9e49
752c19:dd:d9:dd:c25:c25:94de:9e4a/1282c19:dd:d9:dd:c25:c25:94de:9e4a
762c19:dd:d9:dd:c25:c25:94de:9e4b/1282c19:dd:d9:dd:c25:c25:94de:9e4b
772c19:dd:d9:dd:c25:c25:94de:9e4c/1282c19:dd:d9:dd:c25:c25:94de:9e4c
782c19:dd:d9:dd:c25:c25:94de:9e4d/1282c19:dd:d9:dd:c25:c25:94de:9e4d
792c19:dd:d9:dd:c25:c25:94de:9e4e/1282c19:dd:d9:dd:c25:c25:94de:9e4e
802c19:dd:d9:dd:c25:c25:94de:9e4f/1282c19:dd:d9:dd:c25:c25:94de:9e4f
812c19:dd:d9:dd:c25:c25:94de:9e50/1282c19:dd:d9:dd:c25:c25:94de:9e50
822c19:dd:d9:dd:c25:c25:94de:9e51/1282c19:dd:d9:dd:c25:c25:94de:9e51
832c19:dd:d9:dd:c25:c25:94de:9e52/1282c19:dd:d9:dd:c25:c25:94de:9e52
842c19:dd:d9:dd:c25:c25:94de:9e53/1282c19:dd:d9:dd:c25:c25:94de:9e53
852c19:dd:d9:dd:c25:c25:94de:9e54/1282c19:dd:d9:dd:c25:c25:94de:9e54
862c19:dd:d9:dd:c25:c25:94de:9e55/1282c19:dd:d9:dd:c25:c25:94de:9e55
872c19:dd:d9:dd:c25:c25:94de:9e56/1282c19:dd:d9:dd:c25:c25:94de:9e56
882c19:dd:d9:dd:c25:c25:94de:9e57/1282c19:dd:d9:dd:c25:c25:94de:9e57
892c19:dd:d9:dd:c25:c25:94de:9e58/1282c19:dd:d9:dd:c25:c25:94de:9e58
902c19:dd:d9:dd:c25:c25:94de:9e59/1282c19:dd:d9:dd:c25:c25:94de:9e59
912c19:dd:d9:dd:c25:c25:94de:9e5a/1282c19:dd:d9:dd:c25:c25:94de:9e5a
922c19:dd:d9:dd:c25:c25:94de:9e5b/1282c19:dd:d9:dd:c25:c25:94de:9e5b
932c19:dd:d9:dd:c25:c25:94de:9e5c/1282c19:dd:d9:dd:c25:c25:94de:9e5c
942c19:dd:d9:dd:c25:c25:94de:9e5d/1282c19:dd:d9:dd:c25:c25:94de:9e5d
952c19:dd:d9:dd:c25:c25:94de:9e5e/1282c19:dd:d9:dd:c25:c25:94de:9e5e
962c19:dd:d9:dd:c25:c25:94de:9e5f/1282c19:dd:d9:dd:c25:c25:94de:9e5f
972c19:dd:d9:dd:c25:c25:94de:9e60/1282c19:dd:d9:dd:c25:c25:94de:9e60
982c19:dd:d9:dd:c25:c25:94de:9e61/1282c19:dd:d9:dd:c25:c25:94de:9e61
992c19:dd:d9:dd:c25:c25:94de:9e62/1282c19:dd:d9:dd:c25:c25:94de:9e62
1002c19:dd:d9:dd:c25:c25:94de:9e63/1282c19:dd:d9:dd:c25:c25:94de:9e63
1012c19:dd:d9:dd:c25:c25:94de:9e64/1282c19:dd:d9:dd:c25:c25:94de:9e64
1022c19:dd:d9:dd:c25:c25:94de:9e65/1282c19:dd:d9:dd:c25:c25:94de:9e65
1032c19:dd:d9:dd:c25:c25:94de:9e66/1282c19:dd:d9:dd:c25:c25:94de:9e66
1042c19:dd:d9:dd:c25:c25:94de:9e67/1282c19:dd:d9:dd:c25:c25:94de:9e67
1052c19:dd:d9:dd:c25:c25:94de:9e68/1282c19:dd:d9:dd:c25:c25:94de:9e68
1062c19:dd:d9:dd:c25:c25:94de:9e69/1282c19:dd:d9:dd:c25:c25:94de:9e69
1072c19:dd:d9:dd:c25:c25:94de:9e6a/1282c19:dd:d9:dd:c25:c25:94de:9e6a
1082c19:dd:d9:dd:c25:c25:94de:9e6b/1282c19:dd:d9:dd:c25:c25:94de:9e6b
1092c19:dd:d9:dd:c25:c25:94de:9e6c/1282c19:dd:d9:dd:c25:c25:94de:9e6c
1102c19:dd:d9:dd:c25:c25:94de:9e6d/1282c19:dd:d9:dd:c25:c25:94de:9e6d
1112c19:dd:d9:dd:c25:c25:94de:9e6e/1282c19:dd:d9:dd:c25:c25:94de:9e6e
1122c19:dd:d9:dd:c25:c25:94de:9e6f/1282c19:dd:d9:dd:c25:c25:94de:9e6f
1132c19:dd:d9:dd:c25:c25:94de:9e70/1282c19:dd:d9:dd:c25:c25:94de:9e70
1142c19:dd:d9:dd:c25:c25:94de:9e71/1282c19:dd:d9:dd:c25:c25:94de:9e71
1152c19:dd:d9:dd:c25:c25:94de:9e72/1282c19:dd:d9:dd:c25:c25:94de:9e72
1162c19:dd:d9:dd:c25:c25:94de:9e73/1282c19:dd:d9:dd:c25:c25:94de:9e73
1172c19:dd:d9:dd:c25:c25:94de:9e74/1282c19:dd:d9:dd:c25:c25:94de:9e74
1182c19:dd:d9:dd:c25:c25:94de:9e75/1282c19:dd:d9:dd:c25:c25:94de:9e75
1192c19:dd:d9:dd:c25:c25:94de:9e76/1282c19:dd:d9:dd:c25:c25:94de:9e76
1202c19:dd:d9:dd:c25:c25:94de:9e77/1282c19:dd:d9:dd:c25:c25:94de:9e77
1212c19:dd:d9:dd:c25:c25:94de:9e78/1282c19:dd:d9:dd:c25:c25:94de:9e78
1222c19:dd:d9:dd:c25:c25:94de:9e79/1282c19:dd:d9:dd:c25:c25:94de:9e79
1232c19:dd:d9:dd:c25:c25:94de:9e7a/1282c19:dd:d9:dd:c25:c25:94de:9e7a
1242c19:dd:d9:dd:c25:c25:94de:9e7b/1282c19:dd:d9:dd:c25:c25:94de:9e7b
1252c19:dd:d9:dd:c25:c25:94de:9e7c/1282c19:dd:d9:dd:c25:c25:94de:9e7c
1262c19:dd:d9:dd:c25:c25:94de:9e7d/1282c19:dd:d9:dd:c25:c25:94de:9e7d
1272c19:dd:d9:dd:c25:c25:94de:9e7e/1282c19:dd:d9:dd:c25:c25:94de:9e7e
1282c19:dd:d9:dd:c25:c25:94de:9e7f/1282c19:dd:d9:dd:c25:c25:94de:9e7f
1292c19:dd:d9:dd:c25:c25:94de:9e80/1282c19:dd:d9:dd:c25:c25:94de:9e80
1302c19:dd:d9:dd:c25:c25:94de:9e81/1282c19:dd:d9:dd:c25:c25:94de:9e81
1312c19:dd:d9:dd:c25:c25:94de:9e82/1282c19:dd:d9:dd:c25:c25:94de:9e82
1322c19:dd:d9:dd:c25:c25:94de:9e83/1282c19:dd:d9:dd:c25:c25:94de:9e83
1332c19:dd:d9:dd:c25:c25:94de:9e84/1282c19:dd:d9:dd:c25:c25:94de:9e84
1342c19:dd:d9:dd:c25:c25:94de:9e85/1282c19:dd:d9:dd:c25:c25:94de:9e85
1352c19:dd:d9:dd:c25:c25:94de:9e86/1282c19:dd:d9:dd:c25:c25:94de:9e86
1362c19:dd:d9:dd:c25:c25:94de:9e87/1282c19:dd:d9:dd:c25:c25:94de:9e87
1372c19:dd:d9:dd:c25:c25:94de:9e88/1282c19:dd:d9:dd:c25:c25:94de:9e88
1382c19:dd:d9:dd:c25:c25:94de:9e89/1282c19:dd:d9:dd:c25:c25:94de:9e89
1392c19:dd:d9:dd:c25:c25:94de:9e8a/1282c19:dd:d9:dd:c25:c25:94de:9e8a
1402c19:dd:d9:dd:c25:c25:94de:9e8b/1282c19:dd:d9:dd:c25:c25:94de:9e8b
1412c19:dd:d9:dd:c25:c25:94de:9e8c/1282c19:dd:d9:dd:c25:c25:94de:9e8c
1422c19:dd:d9:dd:c25:c25:94de:9e8d/1282c19:dd:d9:dd:c25:c25:94de:9e8d
1432c19:dd:d9:dd:c25:c25:94de:9e8e/1282c19:dd:d9:dd:c25:c25:94de:9e8e
1442c19:dd:d9:dd:c25:c25:94de:9e8f/1282c19:dd:d9:dd:c25:c25:94de:9e8f
1452c19:dd:d9:dd:c25:c25:94de:9e90/1282c19:dd:d9:dd:c25:c25:94de:9e90
1462c19:dd:d9:dd:c25:c25:94de:9e91/1282c19:dd:d9:dd:c25:c25:94de:9e91
1472c19:dd:d9:dd:c25:c25:94de:9e92/1282c19:dd:d9:dd:c25:c25:94de:9e92
1482c19:dd:d9:dd:c25:c25:94de:9e93/1282c19:dd:d9:dd:c25:c25:94de:9e93
1492c19:dd:d9:dd:c25:c25:94de:9e94/1282c19:dd:d9:dd:c25:c25:94de:9e94
1502c19:dd:d9:dd:c25:c25:94de:9e95/1282c19:dd:d9:dd:c25:c25:94de:9e95
1512c19:dd:d9:dd:c25:c25:94de:9e96/1282c19:dd:d9:dd:c25:c25:94de:9e96
1522c19:dd:d9:dd:c25:c25:94de:9e97/1282c19:dd:d9:dd:c25:c25:94de:9e97
1532c19:dd:d9:dd:c25:c25:94de:9e98/1282c19:dd:d9:dd:c25:c25:94de:9e98
1542c19:dd:d9:dd:c25:c25:94de:9e99/1282c19:dd:d9:dd:c25:c25:94de:9e99
1552c19:dd:d9:dd:c25:c25:94de:9e9a/1282c19:dd:d9:dd:c25:c25:94de:9e9a
1562c19:dd:d9:dd:c25:c25:94de:9e9b/1282c19:dd:d9:dd:c25:c25:94de:9e9b
1572c19:dd:d9:dd:c25:c25:94de:9e9c/1282c19:dd:d9:dd:c25:c25:94de:9e9c
1582c19:dd:d9:dd:c25:c25:94de:9e9d/1282c19:dd:d9:dd:c25:c25:94de:9e9d
1592c19:dd:d9:dd:c25:c25:94de:9e9e/1282c19:dd:d9:dd:c25:c25:94de:9e9e
1602c19:dd:d9:dd:c25:c25:94de:9e9f/1282c19:dd:d9:dd:c25:c25:94de:9e9f
1612c19:dd:d9:dd:c25:c25:94de:9ea0/1282c19:dd:d9:dd:c25:c25:94de:9ea0
1622c19:dd:d9:dd:c25:c25:94de:9ea1/1282c19:dd:d9:dd:c25:c25:94de:9ea1
1632c19:dd:d9:dd:c25:c25:94de:9ea2/1282c19:dd:d9:dd:c25:c25:94de:9ea2
1642c19:dd:d9:dd:c25:c25:94de:9ea3/1282c19:dd:d9:dd:c25:c25:94de:9ea3
1652c19:dd:d9:dd:c25:c25:94de:9ea4/1282c19:dd:d9:dd:c25:c25:94de:9ea4
1662c19:dd:d9:dd:c25:c25:94de:9ea5/1282c19:dd:d9:dd:c25:c25:94de:9ea5
1672c19:dd:d9:dd:c25:c25:94de:9ea6/1282c19:dd:d9:dd:c25:c25:94de:9ea6
1682c19:dd:d9:dd:c25:c25:94de:9ea7/1282c19:dd:d9:dd:c25:c25:94de:9ea7
1692c19:dd:d9:dd:c25:c25:94de:9ea8/1282c19:dd:d9:dd:c25:c25:94de:9ea8
1702c19:dd:d9:dd:c25:c25:94de:9ea9/1282c19:dd:d9:dd:c25:c25:94de:9ea9
1712c19:dd:d9:dd:c25:c25:94de:9eaa/1282c19:dd:d9:dd:c25:c25:94de:9eaa
1722c19:dd:d9:dd:c25:c25:94de:9eab/1282c19:dd:d9:dd:c25:c25:94de:9eab
1732c19:dd:d9:dd:c25:c25:94de:9eac/1282c19:dd:d9:dd:c25:c25:94de:9eac
1742c19:dd:d9:dd:c25:c25:94de:9ead/1282c19:dd:d9:dd:c25:c25:94de:9ead
1752c19:dd:d9:dd:c25:c25:94de:9eae/1282c19:dd:d9:dd:c25:c25:94de:9eae
1762c19:dd:d9:dd:c25:c25:94de:9eaf/1282c19:dd:d9:dd:c25:c25:94de:9eaf
1772c19:dd:d9:dd:c25:c25:94de:9eb0/1282c19:dd:d9:dd:c25:c25:94de:9eb0
1782c19:dd:d9:dd:c25:c25:94de:9eb1/1282c19:dd:d9:dd:c25:c25:94de:9eb1
1792c19:dd:d9:dd:c25:c25:94de:9eb2/1282c19:dd:d9:dd:c25:c25:94de:9eb2
1802c19:dd:d9:dd:c25:c25:94de:9eb3/1282c19:dd:d9:dd:c25:c25:94de:9eb3
1812c19:dd:d9:dd:c25:c25:94de:9eb4/1282c19:dd:d9:dd:c25:c25:94de:9eb4
1822c19:dd:d9:dd:c25:c25:94de:9eb5/1282c19:dd:d9:dd:c25:c25:94de:9eb5
1832c19:dd:d9:dd:c25:c25:94de:9eb6/1282c19:dd:d9:dd:c25:c25:94de:9eb6
1842c19:dd:d9:dd:c25:c25:94de:9eb7/1282c19:dd:d9:dd:c25:c25:94de:9eb7
1852c19:dd:d9:dd:c25:c25:94de:9eb8/1282c19:dd:d9:dd:c25:c25:94de:9eb8
1862c19:dd:d9:dd:c25:c25:94de:9eb9/1282c19:dd:d9:dd:c25:c25:94de:9eb9
1872c19:dd:d9:dd:c25:c25:94de:9eba/1282c19:dd:d9:dd:c25:c25:94de:9eba
1882c19:dd:d9:dd:c25:c25:94de:9ebb/1282c19:dd:d9:dd:c25:c25:94de:9ebb
1892c19:dd:d9:dd:c25:c25:94de:9ebc/1282c19:dd:d9:dd:c25:c25:94de:9ebc
1902c19:dd:d9:dd:c25:c25:94de:9ebd/1282c19:dd:d9:dd:c25:c25:94de:9ebd
1912c19:dd:d9:dd:c25:c25:94de:9ebe/1282c19:dd:d9:dd:c25:c25:94de:9ebe
1922c19:dd:d9:dd:c25:c25:94de:9ebf/1282c19:dd:d9:dd:c25:c25:94de:9ebf
1932c19:dd:d9:dd:c25:c25:94de:9ec0/1282c19:dd:d9:dd:c25:c25:94de:9ec0
1942c19:dd:d9:dd:c25:c25:94de:9ec1/1282c19:dd:d9:dd:c25:c25:94de:9ec1
1952c19:dd:d9:dd:c25:c25:94de:9ec2/1282c19:dd:d9:dd:c25:c25:94de:9ec2
1962c19:dd:d9:dd:c25:c25:94de:9ec3/1282c19:dd:d9:dd:c25:c25:94de:9ec3
1972c19:dd:d9:dd:c25:c25:94de:9ec4/1282c19:dd:d9:dd:c25:c25:94de:9ec4
1982c19:dd:d9:dd:c25:c25:94de:9ec5/1282c19:dd:d9:dd:c25:c25:94de:9ec5
1992c19:dd:d9:dd:c25:c25:94de:9ec6/1282c19:dd:d9:dd:c25:c25:94de:9ec6
2002c19:dd:d9:dd:c25:c25:94de:9ec7/1282c19:dd:d9:dd:c25:c25:94de:9ec7
2012c19:dd:d9:dd:c25:c25:94de:9ec8/1282c19:dd:d9:dd:c25:c25:94de:9ec8
2022c19:dd:d9:dd:c25:c25:94de:9ec9/1282c19:dd:d9:dd:c25:c25:94de:9ec9
2032c19:dd:d9:dd:c25:c25:94de:9eca/1282c19:dd:d9:dd:c25:c25:94de:9eca
2042c19:dd:d9:dd:c25:c25:94de:9ecb/1282c19:dd:d9:dd:c25:c25:94de:9ecb
2052c19:dd:d9:dd:c25:c25:94de:9ecc/1282c19:dd:d9:dd:c25:c25:94de:9ecc
2062c19:dd:d9:dd:c25:c25:94de:9ecd/1282c19:dd:d9:dd:c25:c25:94de:9ecd
2072c19:dd:d9:dd:c25:c25:94de:9ece/1282c19:dd:d9:dd:c25:c25:94de:9ece
2082c19:dd:d9:dd:c25:c25:94de:9ecf/1282c19:dd:d9:dd:c25:c25:94de:9ecf
2092c19:dd:d9:dd:c25:c25:94de:9ed0/1282c19:dd:d9:dd:c25:c25:94de:9ed0
2102c19:dd:d9:dd:c25:c25:94de:9ed1/1282c19:dd:d9:dd:c25:c25:94de:9ed1
2112c19:dd:d9:dd:c25:c25:94de:9ed2/1282c19:dd:d9:dd:c25:c25:94de:9ed2
2122c19:dd:d9:dd:c25:c25:94de:9ed3/1282c19:dd:d9:dd:c25:c25:94de:9ed3
2132c19:dd:d9:dd:c25:c25:94de:9ed4/1282c19:dd:d9:dd:c25:c25:94de:9ed4
2142c19:dd:d9:dd:c25:c25:94de:9ed5/1282c19:dd:d9:dd:c25:c25:94de:9ed5
2152c19:dd:d9:dd:c25:c25:94de:9ed6/1282c19:dd:d9:dd:c25:c25:94de:9ed6
2162c19:dd:d9:dd:c25:c25:94de:9ed7/1282c19:dd:d9:dd:c25:c25:94de:9ed7
2172c19:dd:d9:dd:c25:c25:94de:9ed8/1282c19:dd:d9:dd:c25:c25:94de:9ed8
2182c19:dd:d9:dd:c25:c25:94de:9ed9/1282c19:dd:d9:dd:c25:c25:94de:9ed9
2192c19:dd:d9:dd:c25:c25:94de:9eda/1282c19:dd:d9:dd:c25:c25:94de:9eda
2202c19:dd:d9:dd:c25:c25:94de:9edb/1282c19:dd:d9:dd:c25:c25:94de:9edb
2212c19:dd:d9:dd:c25:c25:94de:9edc/1282c19:dd:d9:dd:c25:c25:94de:9edc
2222c19:dd:d9:dd:c25:c25:94de:9edd/1282c19:dd:d9:dd:c25:c25:94de:9edd
2232c19:dd:d9:dd:c25:c25:94de:9ede/1282c19:dd:d9:dd:c25:c25:94de:9ede
2242c19:dd:d9:dd:c25:c25:94de:9edf/1282c19:dd:d9:dd:c25:c25:94de:9edf
2252c19:dd:d9:dd:c25:c25:94de:9ee0/1282c19:dd:d9:dd:c25:c25:94de:9ee0
2262c19:dd:d9:dd:c25:c25:94de:9ee1/1282c19:dd:d9:dd:c25:c25:94de:9ee1
2272c19:dd:d9:dd:c25:c25:94de:9ee2/1282c19:dd:d9:dd:c25:c25:94de:9ee2
2282c19:dd:d9:dd:c25:c25:94de:9ee3/1282c19:dd:d9:dd:c25:c25:94de:9ee3
2292c19:dd:d9:dd:c25:c25:94de:9ee4/1282c19:dd:d9:dd:c25:c25:94de:9ee4
2302c19:dd:d9:dd:c25:c25:94de:9ee5/1282c19:dd:d9:dd:c25:c25:94de:9ee5
2312c19:dd:d9:dd:c25:c25:94de:9ee6/1282c19:dd:d9:dd:c25:c25:94de:9ee6
2322c19:dd:d9:dd:c25:c25:94de:9ee7/1282c19:dd:d9:dd:c25:c25:94de:9ee7
2332c19:dd:d9:dd:c25:c25:94de:9ee8/1282c19:dd:d9:dd:c25:c25:94de:9ee8
2342c19:dd:d9:dd:c25:c25:94de:9ee9/1282c19:dd:d9:dd:c25:c25:94de:9ee9
2352c19:dd:d9:dd:c25:c25:94de:9eea/1282c19:dd:d9:dd:c25:c25:94de:9eea
2362c19:dd:d9:dd:c25:c25:94de:9eeb/1282c19:dd:d9:dd:c25:c25:94de:9eeb
2372c19:dd:d9:dd:c25:c25:94de:9eec/1282c19:dd:d9:dd:c25:c25:94de:9eec
2382c19:dd:d9:dd:c25:c25:94de:9eed/1282c19:dd:d9:dd:c25:c25:94de:9eed
2392c19:dd:d9:dd:c25:c25:94de:9eee/1282c19:dd:d9:dd:c25:c25:94de:9eee
2402c19:dd:d9:dd:c25:c25:94de:9eef/1282c19:dd:d9:dd:c25:c25:94de:9eef
2412c19:dd:d9:dd:c25:c25:94de:9ef0/1282c19:dd:d9:dd:c25:c25:94de:9ef0
2422c19:dd:d9:dd:c25:c25:94de:9ef1/1282c19:dd:d9:dd:c25:c25:94de:9ef1
2432c19:dd:d9:dd:c25:c25:94de:9ef2/1282c19:dd:d9:dd:c25:c25:94de:9ef2
2442c19:dd:d9:dd:c25:c25:94de:9ef3/1282c19:dd:d9:dd:c25:c25:94de:9ef3
2452c19:dd:d9:dd:c25:c25:94de:9ef4/1282c19:dd:d9:dd:c25:c25:94de:9ef4
2462c19:dd:d9:dd:c25:c25:94de:9ef5/1282c19:dd:d9:dd:c25:c25:94de:9ef5
2472c19:dd:d9:dd:c25:c25:94de:9ef6/1282c19:dd:d9:dd:c25:c25:94de:9ef6
2482c19:dd:d9:dd:c25:c25:94de:9ef7/1282c19:dd:d9:dd:c25:c25:94de:9ef7
2492c19:dd:d9:dd:c25:c25:94de:9ef8/1282c19:dd:d9:dd:c25:c25:94de:9ef8
2502c19:dd:d9:dd:c25:c25:94de:9ef9/1282c19:dd:d9:dd:c25:c25:94de:9ef9
2512c19:dd:d9:dd:c25:c25:94de:9efa/1282c19:dd:d9:dd:c25:c25:94de:9efa
2522c19:dd:d9:dd:c25:c25:94de:9efb/1282c19:dd:d9:dd:c25:c25:94de:9efb
2532c19:dd:d9:dd:c25:c25:94de:9efc/1282c19:dd:d9:dd:c25:c25:94de:9efc
2542c19:dd:d9:dd:c25:c25:94de:9efd/1282c19:dd:d9:dd:c25:c25:94de:9efd
2552c19:dd:d9:dd:c25:c25:94de:9efe/1282c19:dd:d9:dd:c25:c25:94de:9efe
2562c19:dd:d9:dd:c25:c25:94de:9eff/1282c19:dd:d9:dd:c25:c25:94de:9eff

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.