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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:d915:8e00/120
First address
2c19:dd:d9:dd:c25:c25:d915:8e00
Last address
2c19:dd:d9:dd:c25:c25:d915:8eff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:8e00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.8.5.1.9.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:d915:8e00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:8e00/1282c19:dd:d9:dd:c25:c25:d915:8e00
22c19:dd:d9:dd:c25:c25:d915:8e01/1282c19:dd:d9:dd:c25:c25:d915:8e01
32c19:dd:d9:dd:c25:c25:d915:8e02/1282c19:dd:d9:dd:c25:c25:d915:8e02
42c19:dd:d9:dd:c25:c25:d915:8e03/1282c19:dd:d9:dd:c25:c25:d915:8e03
52c19:dd:d9:dd:c25:c25:d915:8e04/1282c19:dd:d9:dd:c25:c25:d915:8e04
62c19:dd:d9:dd:c25:c25:d915:8e05/1282c19:dd:d9:dd:c25:c25:d915:8e05
72c19:dd:d9:dd:c25:c25:d915:8e06/1282c19:dd:d9:dd:c25:c25:d915:8e06
82c19:dd:d9:dd:c25:c25:d915:8e07/1282c19:dd:d9:dd:c25:c25:d915:8e07
92c19:dd:d9:dd:c25:c25:d915:8e08/1282c19:dd:d9:dd:c25:c25:d915:8e08
102c19:dd:d9:dd:c25:c25:d915:8e09/1282c19:dd:d9:dd:c25:c25:d915:8e09
112c19:dd:d9:dd:c25:c25:d915:8e0a/1282c19:dd:d9:dd:c25:c25:d915:8e0a
122c19:dd:d9:dd:c25:c25:d915:8e0b/1282c19:dd:d9:dd:c25:c25:d915:8e0b
132c19:dd:d9:dd:c25:c25:d915:8e0c/1282c19:dd:d9:dd:c25:c25:d915:8e0c
142c19:dd:d9:dd:c25:c25:d915:8e0d/1282c19:dd:d9:dd:c25:c25:d915:8e0d
152c19:dd:d9:dd:c25:c25:d915:8e0e/1282c19:dd:d9:dd:c25:c25:d915:8e0e
162c19:dd:d9:dd:c25:c25:d915:8e0f/1282c19:dd:d9:dd:c25:c25:d915:8e0f
172c19:dd:d9:dd:c25:c25:d915:8e10/1282c19:dd:d9:dd:c25:c25:d915:8e10
182c19:dd:d9:dd:c25:c25:d915:8e11/1282c19:dd:d9:dd:c25:c25:d915:8e11
192c19:dd:d9:dd:c25:c25:d915:8e12/1282c19:dd:d9:dd:c25:c25:d915:8e12
202c19:dd:d9:dd:c25:c25:d915:8e13/1282c19:dd:d9:dd:c25:c25:d915:8e13
212c19:dd:d9:dd:c25:c25:d915:8e14/1282c19:dd:d9:dd:c25:c25:d915:8e14
222c19:dd:d9:dd:c25:c25:d915:8e15/1282c19:dd:d9:dd:c25:c25:d915:8e15
232c19:dd:d9:dd:c25:c25:d915:8e16/1282c19:dd:d9:dd:c25:c25:d915:8e16
242c19:dd:d9:dd:c25:c25:d915:8e17/1282c19:dd:d9:dd:c25:c25:d915:8e17
252c19:dd:d9:dd:c25:c25:d915:8e18/1282c19:dd:d9:dd:c25:c25:d915:8e18
262c19:dd:d9:dd:c25:c25:d915:8e19/1282c19:dd:d9:dd:c25:c25:d915:8e19
272c19:dd:d9:dd:c25:c25:d915:8e1a/1282c19:dd:d9:dd:c25:c25:d915:8e1a
282c19:dd:d9:dd:c25:c25:d915:8e1b/1282c19:dd:d9:dd:c25:c25:d915:8e1b
292c19:dd:d9:dd:c25:c25:d915:8e1c/1282c19:dd:d9:dd:c25:c25:d915:8e1c
302c19:dd:d9:dd:c25:c25:d915:8e1d/1282c19:dd:d9:dd:c25:c25:d915:8e1d
312c19:dd:d9:dd:c25:c25:d915:8e1e/1282c19:dd:d9:dd:c25:c25:d915:8e1e
322c19:dd:d9:dd:c25:c25:d915:8e1f/1282c19:dd:d9:dd:c25:c25:d915:8e1f
332c19:dd:d9:dd:c25:c25:d915:8e20/1282c19:dd:d9:dd:c25:c25:d915:8e20
342c19:dd:d9:dd:c25:c25:d915:8e21/1282c19:dd:d9:dd:c25:c25:d915:8e21
352c19:dd:d9:dd:c25:c25:d915:8e22/1282c19:dd:d9:dd:c25:c25:d915:8e22
362c19:dd:d9:dd:c25:c25:d915:8e23/1282c19:dd:d9:dd:c25:c25:d915:8e23
372c19:dd:d9:dd:c25:c25:d915:8e24/1282c19:dd:d9:dd:c25:c25:d915:8e24
382c19:dd:d9:dd:c25:c25:d915:8e25/1282c19:dd:d9:dd:c25:c25:d915:8e25
392c19:dd:d9:dd:c25:c25:d915:8e26/1282c19:dd:d9:dd:c25:c25:d915:8e26
402c19:dd:d9:dd:c25:c25:d915:8e27/1282c19:dd:d9:dd:c25:c25:d915:8e27
412c19:dd:d9:dd:c25:c25:d915:8e28/1282c19:dd:d9:dd:c25:c25:d915:8e28
422c19:dd:d9:dd:c25:c25:d915:8e29/1282c19:dd:d9:dd:c25:c25:d915:8e29
432c19:dd:d9:dd:c25:c25:d915:8e2a/1282c19:dd:d9:dd:c25:c25:d915:8e2a
442c19:dd:d9:dd:c25:c25:d915:8e2b/1282c19:dd:d9:dd:c25:c25:d915:8e2b
452c19:dd:d9:dd:c25:c25:d915:8e2c/1282c19:dd:d9:dd:c25:c25:d915:8e2c
462c19:dd:d9:dd:c25:c25:d915:8e2d/1282c19:dd:d9:dd:c25:c25:d915:8e2d
472c19:dd:d9:dd:c25:c25:d915:8e2e/1282c19:dd:d9:dd:c25:c25:d915:8e2e
482c19:dd:d9:dd:c25:c25:d915:8e2f/1282c19:dd:d9:dd:c25:c25:d915:8e2f
492c19:dd:d9:dd:c25:c25:d915:8e30/1282c19:dd:d9:dd:c25:c25:d915:8e30
502c19:dd:d9:dd:c25:c25:d915:8e31/1282c19:dd:d9:dd:c25:c25:d915:8e31
512c19:dd:d9:dd:c25:c25:d915:8e32/1282c19:dd:d9:dd:c25:c25:d915:8e32
522c19:dd:d9:dd:c25:c25:d915:8e33/1282c19:dd:d9:dd:c25:c25:d915:8e33
532c19:dd:d9:dd:c25:c25:d915:8e34/1282c19:dd:d9:dd:c25:c25:d915:8e34
542c19:dd:d9:dd:c25:c25:d915:8e35/1282c19:dd:d9:dd:c25:c25:d915:8e35
552c19:dd:d9:dd:c25:c25:d915:8e36/1282c19:dd:d9:dd:c25:c25:d915:8e36
562c19:dd:d9:dd:c25:c25:d915:8e37/1282c19:dd:d9:dd:c25:c25:d915:8e37
572c19:dd:d9:dd:c25:c25:d915:8e38/1282c19:dd:d9:dd:c25:c25:d915:8e38
582c19:dd:d9:dd:c25:c25:d915:8e39/1282c19:dd:d9:dd:c25:c25:d915:8e39
592c19:dd:d9:dd:c25:c25:d915:8e3a/1282c19:dd:d9:dd:c25:c25:d915:8e3a
602c19:dd:d9:dd:c25:c25:d915:8e3b/1282c19:dd:d9:dd:c25:c25:d915:8e3b
612c19:dd:d9:dd:c25:c25:d915:8e3c/1282c19:dd:d9:dd:c25:c25:d915:8e3c
622c19:dd:d9:dd:c25:c25:d915:8e3d/1282c19:dd:d9:dd:c25:c25:d915:8e3d
632c19:dd:d9:dd:c25:c25:d915:8e3e/1282c19:dd:d9:dd:c25:c25:d915:8e3e
642c19:dd:d9:dd:c25:c25:d915:8e3f/1282c19:dd:d9:dd:c25:c25:d915:8e3f
652c19:dd:d9:dd:c25:c25:d915:8e40/1282c19:dd:d9:dd:c25:c25:d915:8e40
662c19:dd:d9:dd:c25:c25:d915:8e41/1282c19:dd:d9:dd:c25:c25:d915:8e41
672c19:dd:d9:dd:c25:c25:d915:8e42/1282c19:dd:d9:dd:c25:c25:d915:8e42
682c19:dd:d9:dd:c25:c25:d915:8e43/1282c19:dd:d9:dd:c25:c25:d915:8e43
692c19:dd:d9:dd:c25:c25:d915:8e44/1282c19:dd:d9:dd:c25:c25:d915:8e44
702c19:dd:d9:dd:c25:c25:d915:8e45/1282c19:dd:d9:dd:c25:c25:d915:8e45
712c19:dd:d9:dd:c25:c25:d915:8e46/1282c19:dd:d9:dd:c25:c25:d915:8e46
722c19:dd:d9:dd:c25:c25:d915:8e47/1282c19:dd:d9:dd:c25:c25:d915:8e47
732c19:dd:d9:dd:c25:c25:d915:8e48/1282c19:dd:d9:dd:c25:c25:d915:8e48
742c19:dd:d9:dd:c25:c25:d915:8e49/1282c19:dd:d9:dd:c25:c25:d915:8e49
752c19:dd:d9:dd:c25:c25:d915:8e4a/1282c19:dd:d9:dd:c25:c25:d915:8e4a
762c19:dd:d9:dd:c25:c25:d915:8e4b/1282c19:dd:d9:dd:c25:c25:d915:8e4b
772c19:dd:d9:dd:c25:c25:d915:8e4c/1282c19:dd:d9:dd:c25:c25:d915:8e4c
782c19:dd:d9:dd:c25:c25:d915:8e4d/1282c19:dd:d9:dd:c25:c25:d915:8e4d
792c19:dd:d9:dd:c25:c25:d915:8e4e/1282c19:dd:d9:dd:c25:c25:d915:8e4e
802c19:dd:d9:dd:c25:c25:d915:8e4f/1282c19:dd:d9:dd:c25:c25:d915:8e4f
812c19:dd:d9:dd:c25:c25:d915:8e50/1282c19:dd:d9:dd:c25:c25:d915:8e50
822c19:dd:d9:dd:c25:c25:d915:8e51/1282c19:dd:d9:dd:c25:c25:d915:8e51
832c19:dd:d9:dd:c25:c25:d915:8e52/1282c19:dd:d9:dd:c25:c25:d915:8e52
842c19:dd:d9:dd:c25:c25:d915:8e53/1282c19:dd:d9:dd:c25:c25:d915:8e53
852c19:dd:d9:dd:c25:c25:d915:8e54/1282c19:dd:d9:dd:c25:c25:d915:8e54
862c19:dd:d9:dd:c25:c25:d915:8e55/1282c19:dd:d9:dd:c25:c25:d915:8e55
872c19:dd:d9:dd:c25:c25:d915:8e56/1282c19:dd:d9:dd:c25:c25:d915:8e56
882c19:dd:d9:dd:c25:c25:d915:8e57/1282c19:dd:d9:dd:c25:c25:d915:8e57
892c19:dd:d9:dd:c25:c25:d915:8e58/1282c19:dd:d9:dd:c25:c25:d915:8e58
902c19:dd:d9:dd:c25:c25:d915:8e59/1282c19:dd:d9:dd:c25:c25:d915:8e59
912c19:dd:d9:dd:c25:c25:d915:8e5a/1282c19:dd:d9:dd:c25:c25:d915:8e5a
922c19:dd:d9:dd:c25:c25:d915:8e5b/1282c19:dd:d9:dd:c25:c25:d915:8e5b
932c19:dd:d9:dd:c25:c25:d915:8e5c/1282c19:dd:d9:dd:c25:c25:d915:8e5c
942c19:dd:d9:dd:c25:c25:d915:8e5d/1282c19:dd:d9:dd:c25:c25:d915:8e5d
952c19:dd:d9:dd:c25:c25:d915:8e5e/1282c19:dd:d9:dd:c25:c25:d915:8e5e
962c19:dd:d9:dd:c25:c25:d915:8e5f/1282c19:dd:d9:dd:c25:c25:d915:8e5f
972c19:dd:d9:dd:c25:c25:d915:8e60/1282c19:dd:d9:dd:c25:c25:d915:8e60
982c19:dd:d9:dd:c25:c25:d915:8e61/1282c19:dd:d9:dd:c25:c25:d915:8e61
992c19:dd:d9:dd:c25:c25:d915:8e62/1282c19:dd:d9:dd:c25:c25:d915:8e62
1002c19:dd:d9:dd:c25:c25:d915:8e63/1282c19:dd:d9:dd:c25:c25:d915:8e63
1012c19:dd:d9:dd:c25:c25:d915:8e64/1282c19:dd:d9:dd:c25:c25:d915:8e64
1022c19:dd:d9:dd:c25:c25:d915:8e65/1282c19:dd:d9:dd:c25:c25:d915:8e65
1032c19:dd:d9:dd:c25:c25:d915:8e66/1282c19:dd:d9:dd:c25:c25:d915:8e66
1042c19:dd:d9:dd:c25:c25:d915:8e67/1282c19:dd:d9:dd:c25:c25:d915:8e67
1052c19:dd:d9:dd:c25:c25:d915:8e68/1282c19:dd:d9:dd:c25:c25:d915:8e68
1062c19:dd:d9:dd:c25:c25:d915:8e69/1282c19:dd:d9:dd:c25:c25:d915:8e69
1072c19:dd:d9:dd:c25:c25:d915:8e6a/1282c19:dd:d9:dd:c25:c25:d915:8e6a
1082c19:dd:d9:dd:c25:c25:d915:8e6b/1282c19:dd:d9:dd:c25:c25:d915:8e6b
1092c19:dd:d9:dd:c25:c25:d915:8e6c/1282c19:dd:d9:dd:c25:c25:d915:8e6c
1102c19:dd:d9:dd:c25:c25:d915:8e6d/1282c19:dd:d9:dd:c25:c25:d915:8e6d
1112c19:dd:d9:dd:c25:c25:d915:8e6e/1282c19:dd:d9:dd:c25:c25:d915:8e6e
1122c19:dd:d9:dd:c25:c25:d915:8e6f/1282c19:dd:d9:dd:c25:c25:d915:8e6f
1132c19:dd:d9:dd:c25:c25:d915:8e70/1282c19:dd:d9:dd:c25:c25:d915:8e70
1142c19:dd:d9:dd:c25:c25:d915:8e71/1282c19:dd:d9:dd:c25:c25:d915:8e71
1152c19:dd:d9:dd:c25:c25:d915:8e72/1282c19:dd:d9:dd:c25:c25:d915:8e72
1162c19:dd:d9:dd:c25:c25:d915:8e73/1282c19:dd:d9:dd:c25:c25:d915:8e73
1172c19:dd:d9:dd:c25:c25:d915:8e74/1282c19:dd:d9:dd:c25:c25:d915:8e74
1182c19:dd:d9:dd:c25:c25:d915:8e75/1282c19:dd:d9:dd:c25:c25:d915:8e75
1192c19:dd:d9:dd:c25:c25:d915:8e76/1282c19:dd:d9:dd:c25:c25:d915:8e76
1202c19:dd:d9:dd:c25:c25:d915:8e77/1282c19:dd:d9:dd:c25:c25:d915:8e77
1212c19:dd:d9:dd:c25:c25:d915:8e78/1282c19:dd:d9:dd:c25:c25:d915:8e78
1222c19:dd:d9:dd:c25:c25:d915:8e79/1282c19:dd:d9:dd:c25:c25:d915:8e79
1232c19:dd:d9:dd:c25:c25:d915:8e7a/1282c19:dd:d9:dd:c25:c25:d915:8e7a
1242c19:dd:d9:dd:c25:c25:d915:8e7b/1282c19:dd:d9:dd:c25:c25:d915:8e7b
1252c19:dd:d9:dd:c25:c25:d915:8e7c/1282c19:dd:d9:dd:c25:c25:d915:8e7c
1262c19:dd:d9:dd:c25:c25:d915:8e7d/1282c19:dd:d9:dd:c25:c25:d915:8e7d
1272c19:dd:d9:dd:c25:c25:d915:8e7e/1282c19:dd:d9:dd:c25:c25:d915:8e7e
1282c19:dd:d9:dd:c25:c25:d915:8e7f/1282c19:dd:d9:dd:c25:c25:d915:8e7f
1292c19:dd:d9:dd:c25:c25:d915:8e80/1282c19:dd:d9:dd:c25:c25:d915:8e80
1302c19:dd:d9:dd:c25:c25:d915:8e81/1282c19:dd:d9:dd:c25:c25:d915:8e81
1312c19:dd:d9:dd:c25:c25:d915:8e82/1282c19:dd:d9:dd:c25:c25:d915:8e82
1322c19:dd:d9:dd:c25:c25:d915:8e83/1282c19:dd:d9:dd:c25:c25:d915:8e83
1332c19:dd:d9:dd:c25:c25:d915:8e84/1282c19:dd:d9:dd:c25:c25:d915:8e84
1342c19:dd:d9:dd:c25:c25:d915:8e85/1282c19:dd:d9:dd:c25:c25:d915:8e85
1352c19:dd:d9:dd:c25:c25:d915:8e86/1282c19:dd:d9:dd:c25:c25:d915:8e86
1362c19:dd:d9:dd:c25:c25:d915:8e87/1282c19:dd:d9:dd:c25:c25:d915:8e87
1372c19:dd:d9:dd:c25:c25:d915:8e88/1282c19:dd:d9:dd:c25:c25:d915:8e88
1382c19:dd:d9:dd:c25:c25:d915:8e89/1282c19:dd:d9:dd:c25:c25:d915:8e89
1392c19:dd:d9:dd:c25:c25:d915:8e8a/1282c19:dd:d9:dd:c25:c25:d915:8e8a
1402c19:dd:d9:dd:c25:c25:d915:8e8b/1282c19:dd:d9:dd:c25:c25:d915:8e8b
1412c19:dd:d9:dd:c25:c25:d915:8e8c/1282c19:dd:d9:dd:c25:c25:d915:8e8c
1422c19:dd:d9:dd:c25:c25:d915:8e8d/1282c19:dd:d9:dd:c25:c25:d915:8e8d
1432c19:dd:d9:dd:c25:c25:d915:8e8e/1282c19:dd:d9:dd:c25:c25:d915:8e8e
1442c19:dd:d9:dd:c25:c25:d915:8e8f/1282c19:dd:d9:dd:c25:c25:d915:8e8f
1452c19:dd:d9:dd:c25:c25:d915:8e90/1282c19:dd:d9:dd:c25:c25:d915:8e90
1462c19:dd:d9:dd:c25:c25:d915:8e91/1282c19:dd:d9:dd:c25:c25:d915:8e91
1472c19:dd:d9:dd:c25:c25:d915:8e92/1282c19:dd:d9:dd:c25:c25:d915:8e92
1482c19:dd:d9:dd:c25:c25:d915:8e93/1282c19:dd:d9:dd:c25:c25:d915:8e93
1492c19:dd:d9:dd:c25:c25:d915:8e94/1282c19:dd:d9:dd:c25:c25:d915:8e94
1502c19:dd:d9:dd:c25:c25:d915:8e95/1282c19:dd:d9:dd:c25:c25:d915:8e95
1512c19:dd:d9:dd:c25:c25:d915:8e96/1282c19:dd:d9:dd:c25:c25:d915:8e96
1522c19:dd:d9:dd:c25:c25:d915:8e97/1282c19:dd:d9:dd:c25:c25:d915:8e97
1532c19:dd:d9:dd:c25:c25:d915:8e98/1282c19:dd:d9:dd:c25:c25:d915:8e98
1542c19:dd:d9:dd:c25:c25:d915:8e99/1282c19:dd:d9:dd:c25:c25:d915:8e99
1552c19:dd:d9:dd:c25:c25:d915:8e9a/1282c19:dd:d9:dd:c25:c25:d915:8e9a
1562c19:dd:d9:dd:c25:c25:d915:8e9b/1282c19:dd:d9:dd:c25:c25:d915:8e9b
1572c19:dd:d9:dd:c25:c25:d915:8e9c/1282c19:dd:d9:dd:c25:c25:d915:8e9c
1582c19:dd:d9:dd:c25:c25:d915:8e9d/1282c19:dd:d9:dd:c25:c25:d915:8e9d
1592c19:dd:d9:dd:c25:c25:d915:8e9e/1282c19:dd:d9:dd:c25:c25:d915:8e9e
1602c19:dd:d9:dd:c25:c25:d915:8e9f/1282c19:dd:d9:dd:c25:c25:d915:8e9f
1612c19:dd:d9:dd:c25:c25:d915:8ea0/1282c19:dd:d9:dd:c25:c25:d915:8ea0
1622c19:dd:d9:dd:c25:c25:d915:8ea1/1282c19:dd:d9:dd:c25:c25:d915:8ea1
1632c19:dd:d9:dd:c25:c25:d915:8ea2/1282c19:dd:d9:dd:c25:c25:d915:8ea2
1642c19:dd:d9:dd:c25:c25:d915:8ea3/1282c19:dd:d9:dd:c25:c25:d915:8ea3
1652c19:dd:d9:dd:c25:c25:d915:8ea4/1282c19:dd:d9:dd:c25:c25:d915:8ea4
1662c19:dd:d9:dd:c25:c25:d915:8ea5/1282c19:dd:d9:dd:c25:c25:d915:8ea5
1672c19:dd:d9:dd:c25:c25:d915:8ea6/1282c19:dd:d9:dd:c25:c25:d915:8ea6
1682c19:dd:d9:dd:c25:c25:d915:8ea7/1282c19:dd:d9:dd:c25:c25:d915:8ea7
1692c19:dd:d9:dd:c25:c25:d915:8ea8/1282c19:dd:d9:dd:c25:c25:d915:8ea8
1702c19:dd:d9:dd:c25:c25:d915:8ea9/1282c19:dd:d9:dd:c25:c25:d915:8ea9
1712c19:dd:d9:dd:c25:c25:d915:8eaa/1282c19:dd:d9:dd:c25:c25:d915:8eaa
1722c19:dd:d9:dd:c25:c25:d915:8eab/1282c19:dd:d9:dd:c25:c25:d915:8eab
1732c19:dd:d9:dd:c25:c25:d915:8eac/1282c19:dd:d9:dd:c25:c25:d915:8eac
1742c19:dd:d9:dd:c25:c25:d915:8ead/1282c19:dd:d9:dd:c25:c25:d915:8ead
1752c19:dd:d9:dd:c25:c25:d915:8eae/1282c19:dd:d9:dd:c25:c25:d915:8eae
1762c19:dd:d9:dd:c25:c25:d915:8eaf/1282c19:dd:d9:dd:c25:c25:d915:8eaf
1772c19:dd:d9:dd:c25:c25:d915:8eb0/1282c19:dd:d9:dd:c25:c25:d915:8eb0
1782c19:dd:d9:dd:c25:c25:d915:8eb1/1282c19:dd:d9:dd:c25:c25:d915:8eb1
1792c19:dd:d9:dd:c25:c25:d915:8eb2/1282c19:dd:d9:dd:c25:c25:d915:8eb2
1802c19:dd:d9:dd:c25:c25:d915:8eb3/1282c19:dd:d9:dd:c25:c25:d915:8eb3
1812c19:dd:d9:dd:c25:c25:d915:8eb4/1282c19:dd:d9:dd:c25:c25:d915:8eb4
1822c19:dd:d9:dd:c25:c25:d915:8eb5/1282c19:dd:d9:dd:c25:c25:d915:8eb5
1832c19:dd:d9:dd:c25:c25:d915:8eb6/1282c19:dd:d9:dd:c25:c25:d915:8eb6
1842c19:dd:d9:dd:c25:c25:d915:8eb7/1282c19:dd:d9:dd:c25:c25:d915:8eb7
1852c19:dd:d9:dd:c25:c25:d915:8eb8/1282c19:dd:d9:dd:c25:c25:d915:8eb8
1862c19:dd:d9:dd:c25:c25:d915:8eb9/1282c19:dd:d9:dd:c25:c25:d915:8eb9
1872c19:dd:d9:dd:c25:c25:d915:8eba/1282c19:dd:d9:dd:c25:c25:d915:8eba
1882c19:dd:d9:dd:c25:c25:d915:8ebb/1282c19:dd:d9:dd:c25:c25:d915:8ebb
1892c19:dd:d9:dd:c25:c25:d915:8ebc/1282c19:dd:d9:dd:c25:c25:d915:8ebc
1902c19:dd:d9:dd:c25:c25:d915:8ebd/1282c19:dd:d9:dd:c25:c25:d915:8ebd
1912c19:dd:d9:dd:c25:c25:d915:8ebe/1282c19:dd:d9:dd:c25:c25:d915:8ebe
1922c19:dd:d9:dd:c25:c25:d915:8ebf/1282c19:dd:d9:dd:c25:c25:d915:8ebf
1932c19:dd:d9:dd:c25:c25:d915:8ec0/1282c19:dd:d9:dd:c25:c25:d915:8ec0
1942c19:dd:d9:dd:c25:c25:d915:8ec1/1282c19:dd:d9:dd:c25:c25:d915:8ec1
1952c19:dd:d9:dd:c25:c25:d915:8ec2/1282c19:dd:d9:dd:c25:c25:d915:8ec2
1962c19:dd:d9:dd:c25:c25:d915:8ec3/1282c19:dd:d9:dd:c25:c25:d915:8ec3
1972c19:dd:d9:dd:c25:c25:d915:8ec4/1282c19:dd:d9:dd:c25:c25:d915:8ec4
1982c19:dd:d9:dd:c25:c25:d915:8ec5/1282c19:dd:d9:dd:c25:c25:d915:8ec5
1992c19:dd:d9:dd:c25:c25:d915:8ec6/1282c19:dd:d9:dd:c25:c25:d915:8ec6
2002c19:dd:d9:dd:c25:c25:d915:8ec7/1282c19:dd:d9:dd:c25:c25:d915:8ec7
2012c19:dd:d9:dd:c25:c25:d915:8ec8/1282c19:dd:d9:dd:c25:c25:d915:8ec8
2022c19:dd:d9:dd:c25:c25:d915:8ec9/1282c19:dd:d9:dd:c25:c25:d915:8ec9
2032c19:dd:d9:dd:c25:c25:d915:8eca/1282c19:dd:d9:dd:c25:c25:d915:8eca
2042c19:dd:d9:dd:c25:c25:d915:8ecb/1282c19:dd:d9:dd:c25:c25:d915:8ecb
2052c19:dd:d9:dd:c25:c25:d915:8ecc/1282c19:dd:d9:dd:c25:c25:d915:8ecc
2062c19:dd:d9:dd:c25:c25:d915:8ecd/1282c19:dd:d9:dd:c25:c25:d915:8ecd
2072c19:dd:d9:dd:c25:c25:d915:8ece/1282c19:dd:d9:dd:c25:c25:d915:8ece
2082c19:dd:d9:dd:c25:c25:d915:8ecf/1282c19:dd:d9:dd:c25:c25:d915:8ecf
2092c19:dd:d9:dd:c25:c25:d915:8ed0/1282c19:dd:d9:dd:c25:c25:d915:8ed0
2102c19:dd:d9:dd:c25:c25:d915:8ed1/1282c19:dd:d9:dd:c25:c25:d915:8ed1
2112c19:dd:d9:dd:c25:c25:d915:8ed2/1282c19:dd:d9:dd:c25:c25:d915:8ed2
2122c19:dd:d9:dd:c25:c25:d915:8ed3/1282c19:dd:d9:dd:c25:c25:d915:8ed3
2132c19:dd:d9:dd:c25:c25:d915:8ed4/1282c19:dd:d9:dd:c25:c25:d915:8ed4
2142c19:dd:d9:dd:c25:c25:d915:8ed5/1282c19:dd:d9:dd:c25:c25:d915:8ed5
2152c19:dd:d9:dd:c25:c25:d915:8ed6/1282c19:dd:d9:dd:c25:c25:d915:8ed6
2162c19:dd:d9:dd:c25:c25:d915:8ed7/1282c19:dd:d9:dd:c25:c25:d915:8ed7
2172c19:dd:d9:dd:c25:c25:d915:8ed8/1282c19:dd:d9:dd:c25:c25:d915:8ed8
2182c19:dd:d9:dd:c25:c25:d915:8ed9/1282c19:dd:d9:dd:c25:c25:d915:8ed9
2192c19:dd:d9:dd:c25:c25:d915:8eda/1282c19:dd:d9:dd:c25:c25:d915:8eda
2202c19:dd:d9:dd:c25:c25:d915:8edb/1282c19:dd:d9:dd:c25:c25:d915:8edb
2212c19:dd:d9:dd:c25:c25:d915:8edc/1282c19:dd:d9:dd:c25:c25:d915:8edc
2222c19:dd:d9:dd:c25:c25:d915:8edd/1282c19:dd:d9:dd:c25:c25:d915:8edd
2232c19:dd:d9:dd:c25:c25:d915:8ede/1282c19:dd:d9:dd:c25:c25:d915:8ede
2242c19:dd:d9:dd:c25:c25:d915:8edf/1282c19:dd:d9:dd:c25:c25:d915:8edf
2252c19:dd:d9:dd:c25:c25:d915:8ee0/1282c19:dd:d9:dd:c25:c25:d915:8ee0
2262c19:dd:d9:dd:c25:c25:d915:8ee1/1282c19:dd:d9:dd:c25:c25:d915:8ee1
2272c19:dd:d9:dd:c25:c25:d915:8ee2/1282c19:dd:d9:dd:c25:c25:d915:8ee2
2282c19:dd:d9:dd:c25:c25:d915:8ee3/1282c19:dd:d9:dd:c25:c25:d915:8ee3
2292c19:dd:d9:dd:c25:c25:d915:8ee4/1282c19:dd:d9:dd:c25:c25:d915:8ee4
2302c19:dd:d9:dd:c25:c25:d915:8ee5/1282c19:dd:d9:dd:c25:c25:d915:8ee5
2312c19:dd:d9:dd:c25:c25:d915:8ee6/1282c19:dd:d9:dd:c25:c25:d915:8ee6
2322c19:dd:d9:dd:c25:c25:d915:8ee7/1282c19:dd:d9:dd:c25:c25:d915:8ee7
2332c19:dd:d9:dd:c25:c25:d915:8ee8/1282c19:dd:d9:dd:c25:c25:d915:8ee8
2342c19:dd:d9:dd:c25:c25:d915:8ee9/1282c19:dd:d9:dd:c25:c25:d915:8ee9
2352c19:dd:d9:dd:c25:c25:d915:8eea/1282c19:dd:d9:dd:c25:c25:d915:8eea
2362c19:dd:d9:dd:c25:c25:d915:8eeb/1282c19:dd:d9:dd:c25:c25:d915:8eeb
2372c19:dd:d9:dd:c25:c25:d915:8eec/1282c19:dd:d9:dd:c25:c25:d915:8eec
2382c19:dd:d9:dd:c25:c25:d915:8eed/1282c19:dd:d9:dd:c25:c25:d915:8eed
2392c19:dd:d9:dd:c25:c25:d915:8eee/1282c19:dd:d9:dd:c25:c25:d915:8eee
2402c19:dd:d9:dd:c25:c25:d915:8eef/1282c19:dd:d9:dd:c25:c25:d915:8eef
2412c19:dd:d9:dd:c25:c25:d915:8ef0/1282c19:dd:d9:dd:c25:c25:d915:8ef0
2422c19:dd:d9:dd:c25:c25:d915:8ef1/1282c19:dd:d9:dd:c25:c25:d915:8ef1
2432c19:dd:d9:dd:c25:c25:d915:8ef2/1282c19:dd:d9:dd:c25:c25:d915:8ef2
2442c19:dd:d9:dd:c25:c25:d915:8ef3/1282c19:dd:d9:dd:c25:c25:d915:8ef3
2452c19:dd:d9:dd:c25:c25:d915:8ef4/1282c19:dd:d9:dd:c25:c25:d915:8ef4
2462c19:dd:d9:dd:c25:c25:d915:8ef5/1282c19:dd:d9:dd:c25:c25:d915:8ef5
2472c19:dd:d9:dd:c25:c25:d915:8ef6/1282c19:dd:d9:dd:c25:c25:d915:8ef6
2482c19:dd:d9:dd:c25:c25:d915:8ef7/1282c19:dd:d9:dd:c25:c25:d915:8ef7
2492c19:dd:d9:dd:c25:c25:d915:8ef8/1282c19:dd:d9:dd:c25:c25:d915:8ef8
2502c19:dd:d9:dd:c25:c25:d915:8ef9/1282c19:dd:d9:dd:c25:c25:d915:8ef9
2512c19:dd:d9:dd:c25:c25:d915:8efa/1282c19:dd:d9:dd:c25:c25:d915:8efa
2522c19:dd:d9:dd:c25:c25:d915:8efb/1282c19:dd:d9:dd:c25:c25:d915:8efb
2532c19:dd:d9:dd:c25:c25:d915:8efc/1282c19:dd:d9:dd:c25:c25:d915:8efc
2542c19:dd:d9:dd:c25:c25:d915:8efd/1282c19:dd:d9:dd:c25:c25:d915:8efd
2552c19:dd:d9:dd:c25:c25:d915:8efe/1282c19:dd:d9:dd:c25:c25:d915:8efe
2562c19:dd:d9:dd:c25:c25:d915:8eff/1282c19:dd:d9:dd:c25:c25:d915:8eff

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.