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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:4b00/120
First address
2c19:dd:d9:dd:c25:c25:94de:4b00
Last address
2c19:dd:d9:dd:c25:c25:94de:4bff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:4b00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
b.4.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:4b00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:4b00/1282c19:dd:d9:dd:c25:c25:94de:4b00
22c19:dd:d9:dd:c25:c25:94de:4b01/1282c19:dd:d9:dd:c25:c25:94de:4b01
32c19:dd:d9:dd:c25:c25:94de:4b02/1282c19:dd:d9:dd:c25:c25:94de:4b02
42c19:dd:d9:dd:c25:c25:94de:4b03/1282c19:dd:d9:dd:c25:c25:94de:4b03
52c19:dd:d9:dd:c25:c25:94de:4b04/1282c19:dd:d9:dd:c25:c25:94de:4b04
62c19:dd:d9:dd:c25:c25:94de:4b05/1282c19:dd:d9:dd:c25:c25:94de:4b05
72c19:dd:d9:dd:c25:c25:94de:4b06/1282c19:dd:d9:dd:c25:c25:94de:4b06
82c19:dd:d9:dd:c25:c25:94de:4b07/1282c19:dd:d9:dd:c25:c25:94de:4b07
92c19:dd:d9:dd:c25:c25:94de:4b08/1282c19:dd:d9:dd:c25:c25:94de:4b08
102c19:dd:d9:dd:c25:c25:94de:4b09/1282c19:dd:d9:dd:c25:c25:94de:4b09
112c19:dd:d9:dd:c25:c25:94de:4b0a/1282c19:dd:d9:dd:c25:c25:94de:4b0a
122c19:dd:d9:dd:c25:c25:94de:4b0b/1282c19:dd:d9:dd:c25:c25:94de:4b0b
132c19:dd:d9:dd:c25:c25:94de:4b0c/1282c19:dd:d9:dd:c25:c25:94de:4b0c
142c19:dd:d9:dd:c25:c25:94de:4b0d/1282c19:dd:d9:dd:c25:c25:94de:4b0d
152c19:dd:d9:dd:c25:c25:94de:4b0e/1282c19:dd:d9:dd:c25:c25:94de:4b0e
162c19:dd:d9:dd:c25:c25:94de:4b0f/1282c19:dd:d9:dd:c25:c25:94de:4b0f
172c19:dd:d9:dd:c25:c25:94de:4b10/1282c19:dd:d9:dd:c25:c25:94de:4b10
182c19:dd:d9:dd:c25:c25:94de:4b11/1282c19:dd:d9:dd:c25:c25:94de:4b11
192c19:dd:d9:dd:c25:c25:94de:4b12/1282c19:dd:d9:dd:c25:c25:94de:4b12
202c19:dd:d9:dd:c25:c25:94de:4b13/1282c19:dd:d9:dd:c25:c25:94de:4b13
212c19:dd:d9:dd:c25:c25:94de:4b14/1282c19:dd:d9:dd:c25:c25:94de:4b14
222c19:dd:d9:dd:c25:c25:94de:4b15/1282c19:dd:d9:dd:c25:c25:94de:4b15
232c19:dd:d9:dd:c25:c25:94de:4b16/1282c19:dd:d9:dd:c25:c25:94de:4b16
242c19:dd:d9:dd:c25:c25:94de:4b17/1282c19:dd:d9:dd:c25:c25:94de:4b17
252c19:dd:d9:dd:c25:c25:94de:4b18/1282c19:dd:d9:dd:c25:c25:94de:4b18
262c19:dd:d9:dd:c25:c25:94de:4b19/1282c19:dd:d9:dd:c25:c25:94de:4b19
272c19:dd:d9:dd:c25:c25:94de:4b1a/1282c19:dd:d9:dd:c25:c25:94de:4b1a
282c19:dd:d9:dd:c25:c25:94de:4b1b/1282c19:dd:d9:dd:c25:c25:94de:4b1b
292c19:dd:d9:dd:c25:c25:94de:4b1c/1282c19:dd:d9:dd:c25:c25:94de:4b1c
302c19:dd:d9:dd:c25:c25:94de:4b1d/1282c19:dd:d9:dd:c25:c25:94de:4b1d
312c19:dd:d9:dd:c25:c25:94de:4b1e/1282c19:dd:d9:dd:c25:c25:94de:4b1e
322c19:dd:d9:dd:c25:c25:94de:4b1f/1282c19:dd:d9:dd:c25:c25:94de:4b1f
332c19:dd:d9:dd:c25:c25:94de:4b20/1282c19:dd:d9:dd:c25:c25:94de:4b20
342c19:dd:d9:dd:c25:c25:94de:4b21/1282c19:dd:d9:dd:c25:c25:94de:4b21
352c19:dd:d9:dd:c25:c25:94de:4b22/1282c19:dd:d9:dd:c25:c25:94de:4b22
362c19:dd:d9:dd:c25:c25:94de:4b23/1282c19:dd:d9:dd:c25:c25:94de:4b23
372c19:dd:d9:dd:c25:c25:94de:4b24/1282c19:dd:d9:dd:c25:c25:94de:4b24
382c19:dd:d9:dd:c25:c25:94de:4b25/1282c19:dd:d9:dd:c25:c25:94de:4b25
392c19:dd:d9:dd:c25:c25:94de:4b26/1282c19:dd:d9:dd:c25:c25:94de:4b26
402c19:dd:d9:dd:c25:c25:94de:4b27/1282c19:dd:d9:dd:c25:c25:94de:4b27
412c19:dd:d9:dd:c25:c25:94de:4b28/1282c19:dd:d9:dd:c25:c25:94de:4b28
422c19:dd:d9:dd:c25:c25:94de:4b29/1282c19:dd:d9:dd:c25:c25:94de:4b29
432c19:dd:d9:dd:c25:c25:94de:4b2a/1282c19:dd:d9:dd:c25:c25:94de:4b2a
442c19:dd:d9:dd:c25:c25:94de:4b2b/1282c19:dd:d9:dd:c25:c25:94de:4b2b
452c19:dd:d9:dd:c25:c25:94de:4b2c/1282c19:dd:d9:dd:c25:c25:94de:4b2c
462c19:dd:d9:dd:c25:c25:94de:4b2d/1282c19:dd:d9:dd:c25:c25:94de:4b2d
472c19:dd:d9:dd:c25:c25:94de:4b2e/1282c19:dd:d9:dd:c25:c25:94de:4b2e
482c19:dd:d9:dd:c25:c25:94de:4b2f/1282c19:dd:d9:dd:c25:c25:94de:4b2f
492c19:dd:d9:dd:c25:c25:94de:4b30/1282c19:dd:d9:dd:c25:c25:94de:4b30
502c19:dd:d9:dd:c25:c25:94de:4b31/1282c19:dd:d9:dd:c25:c25:94de:4b31
512c19:dd:d9:dd:c25:c25:94de:4b32/1282c19:dd:d9:dd:c25:c25:94de:4b32
522c19:dd:d9:dd:c25:c25:94de:4b33/1282c19:dd:d9:dd:c25:c25:94de:4b33
532c19:dd:d9:dd:c25:c25:94de:4b34/1282c19:dd:d9:dd:c25:c25:94de:4b34
542c19:dd:d9:dd:c25:c25:94de:4b35/1282c19:dd:d9:dd:c25:c25:94de:4b35
552c19:dd:d9:dd:c25:c25:94de:4b36/1282c19:dd:d9:dd:c25:c25:94de:4b36
562c19:dd:d9:dd:c25:c25:94de:4b37/1282c19:dd:d9:dd:c25:c25:94de:4b37
572c19:dd:d9:dd:c25:c25:94de:4b38/1282c19:dd:d9:dd:c25:c25:94de:4b38
582c19:dd:d9:dd:c25:c25:94de:4b39/1282c19:dd:d9:dd:c25:c25:94de:4b39
592c19:dd:d9:dd:c25:c25:94de:4b3a/1282c19:dd:d9:dd:c25:c25:94de:4b3a
602c19:dd:d9:dd:c25:c25:94de:4b3b/1282c19:dd:d9:dd:c25:c25:94de:4b3b
612c19:dd:d9:dd:c25:c25:94de:4b3c/1282c19:dd:d9:dd:c25:c25:94de:4b3c
622c19:dd:d9:dd:c25:c25:94de:4b3d/1282c19:dd:d9:dd:c25:c25:94de:4b3d
632c19:dd:d9:dd:c25:c25:94de:4b3e/1282c19:dd:d9:dd:c25:c25:94de:4b3e
642c19:dd:d9:dd:c25:c25:94de:4b3f/1282c19:dd:d9:dd:c25:c25:94de:4b3f
652c19:dd:d9:dd:c25:c25:94de:4b40/1282c19:dd:d9:dd:c25:c25:94de:4b40
662c19:dd:d9:dd:c25:c25:94de:4b41/1282c19:dd:d9:dd:c25:c25:94de:4b41
672c19:dd:d9:dd:c25:c25:94de:4b42/1282c19:dd:d9:dd:c25:c25:94de:4b42
682c19:dd:d9:dd:c25:c25:94de:4b43/1282c19:dd:d9:dd:c25:c25:94de:4b43
692c19:dd:d9:dd:c25:c25:94de:4b44/1282c19:dd:d9:dd:c25:c25:94de:4b44
702c19:dd:d9:dd:c25:c25:94de:4b45/1282c19:dd:d9:dd:c25:c25:94de:4b45
712c19:dd:d9:dd:c25:c25:94de:4b46/1282c19:dd:d9:dd:c25:c25:94de:4b46
722c19:dd:d9:dd:c25:c25:94de:4b47/1282c19:dd:d9:dd:c25:c25:94de:4b47
732c19:dd:d9:dd:c25:c25:94de:4b48/1282c19:dd:d9:dd:c25:c25:94de:4b48
742c19:dd:d9:dd:c25:c25:94de:4b49/1282c19:dd:d9:dd:c25:c25:94de:4b49
752c19:dd:d9:dd:c25:c25:94de:4b4a/1282c19:dd:d9:dd:c25:c25:94de:4b4a
762c19:dd:d9:dd:c25:c25:94de:4b4b/1282c19:dd:d9:dd:c25:c25:94de:4b4b
772c19:dd:d9:dd:c25:c25:94de:4b4c/1282c19:dd:d9:dd:c25:c25:94de:4b4c
782c19:dd:d9:dd:c25:c25:94de:4b4d/1282c19:dd:d9:dd:c25:c25:94de:4b4d
792c19:dd:d9:dd:c25:c25:94de:4b4e/1282c19:dd:d9:dd:c25:c25:94de:4b4e
802c19:dd:d9:dd:c25:c25:94de:4b4f/1282c19:dd:d9:dd:c25:c25:94de:4b4f
812c19:dd:d9:dd:c25:c25:94de:4b50/1282c19:dd:d9:dd:c25:c25:94de:4b50
822c19:dd:d9:dd:c25:c25:94de:4b51/1282c19:dd:d9:dd:c25:c25:94de:4b51
832c19:dd:d9:dd:c25:c25:94de:4b52/1282c19:dd:d9:dd:c25:c25:94de:4b52
842c19:dd:d9:dd:c25:c25:94de:4b53/1282c19:dd:d9:dd:c25:c25:94de:4b53
852c19:dd:d9:dd:c25:c25:94de:4b54/1282c19:dd:d9:dd:c25:c25:94de:4b54
862c19:dd:d9:dd:c25:c25:94de:4b55/1282c19:dd:d9:dd:c25:c25:94de:4b55
872c19:dd:d9:dd:c25:c25:94de:4b56/1282c19:dd:d9:dd:c25:c25:94de:4b56
882c19:dd:d9:dd:c25:c25:94de:4b57/1282c19:dd:d9:dd:c25:c25:94de:4b57
892c19:dd:d9:dd:c25:c25:94de:4b58/1282c19:dd:d9:dd:c25:c25:94de:4b58
902c19:dd:d9:dd:c25:c25:94de:4b59/1282c19:dd:d9:dd:c25:c25:94de:4b59
912c19:dd:d9:dd:c25:c25:94de:4b5a/1282c19:dd:d9:dd:c25:c25:94de:4b5a
922c19:dd:d9:dd:c25:c25:94de:4b5b/1282c19:dd:d9:dd:c25:c25:94de:4b5b
932c19:dd:d9:dd:c25:c25:94de:4b5c/1282c19:dd:d9:dd:c25:c25:94de:4b5c
942c19:dd:d9:dd:c25:c25:94de:4b5d/1282c19:dd:d9:dd:c25:c25:94de:4b5d
952c19:dd:d9:dd:c25:c25:94de:4b5e/1282c19:dd:d9:dd:c25:c25:94de:4b5e
962c19:dd:d9:dd:c25:c25:94de:4b5f/1282c19:dd:d9:dd:c25:c25:94de:4b5f
972c19:dd:d9:dd:c25:c25:94de:4b60/1282c19:dd:d9:dd:c25:c25:94de:4b60
982c19:dd:d9:dd:c25:c25:94de:4b61/1282c19:dd:d9:dd:c25:c25:94de:4b61
992c19:dd:d9:dd:c25:c25:94de:4b62/1282c19:dd:d9:dd:c25:c25:94de:4b62
1002c19:dd:d9:dd:c25:c25:94de:4b63/1282c19:dd:d9:dd:c25:c25:94de:4b63
1012c19:dd:d9:dd:c25:c25:94de:4b64/1282c19:dd:d9:dd:c25:c25:94de:4b64
1022c19:dd:d9:dd:c25:c25:94de:4b65/1282c19:dd:d9:dd:c25:c25:94de:4b65
1032c19:dd:d9:dd:c25:c25:94de:4b66/1282c19:dd:d9:dd:c25:c25:94de:4b66
1042c19:dd:d9:dd:c25:c25:94de:4b67/1282c19:dd:d9:dd:c25:c25:94de:4b67
1052c19:dd:d9:dd:c25:c25:94de:4b68/1282c19:dd:d9:dd:c25:c25:94de:4b68
1062c19:dd:d9:dd:c25:c25:94de:4b69/1282c19:dd:d9:dd:c25:c25:94de:4b69
1072c19:dd:d9:dd:c25:c25:94de:4b6a/1282c19:dd:d9:dd:c25:c25:94de:4b6a
1082c19:dd:d9:dd:c25:c25:94de:4b6b/1282c19:dd:d9:dd:c25:c25:94de:4b6b
1092c19:dd:d9:dd:c25:c25:94de:4b6c/1282c19:dd:d9:dd:c25:c25:94de:4b6c
1102c19:dd:d9:dd:c25:c25:94de:4b6d/1282c19:dd:d9:dd:c25:c25:94de:4b6d
1112c19:dd:d9:dd:c25:c25:94de:4b6e/1282c19:dd:d9:dd:c25:c25:94de:4b6e
1122c19:dd:d9:dd:c25:c25:94de:4b6f/1282c19:dd:d9:dd:c25:c25:94de:4b6f
1132c19:dd:d9:dd:c25:c25:94de:4b70/1282c19:dd:d9:dd:c25:c25:94de:4b70
1142c19:dd:d9:dd:c25:c25:94de:4b71/1282c19:dd:d9:dd:c25:c25:94de:4b71
1152c19:dd:d9:dd:c25:c25:94de:4b72/1282c19:dd:d9:dd:c25:c25:94de:4b72
1162c19:dd:d9:dd:c25:c25:94de:4b73/1282c19:dd:d9:dd:c25:c25:94de:4b73
1172c19:dd:d9:dd:c25:c25:94de:4b74/1282c19:dd:d9:dd:c25:c25:94de:4b74
1182c19:dd:d9:dd:c25:c25:94de:4b75/1282c19:dd:d9:dd:c25:c25:94de:4b75
1192c19:dd:d9:dd:c25:c25:94de:4b76/1282c19:dd:d9:dd:c25:c25:94de:4b76
1202c19:dd:d9:dd:c25:c25:94de:4b77/1282c19:dd:d9:dd:c25:c25:94de:4b77
1212c19:dd:d9:dd:c25:c25:94de:4b78/1282c19:dd:d9:dd:c25:c25:94de:4b78
1222c19:dd:d9:dd:c25:c25:94de:4b79/1282c19:dd:d9:dd:c25:c25:94de:4b79
1232c19:dd:d9:dd:c25:c25:94de:4b7a/1282c19:dd:d9:dd:c25:c25:94de:4b7a
1242c19:dd:d9:dd:c25:c25:94de:4b7b/1282c19:dd:d9:dd:c25:c25:94de:4b7b
1252c19:dd:d9:dd:c25:c25:94de:4b7c/1282c19:dd:d9:dd:c25:c25:94de:4b7c
1262c19:dd:d9:dd:c25:c25:94de:4b7d/1282c19:dd:d9:dd:c25:c25:94de:4b7d
1272c19:dd:d9:dd:c25:c25:94de:4b7e/1282c19:dd:d9:dd:c25:c25:94de:4b7e
1282c19:dd:d9:dd:c25:c25:94de:4b7f/1282c19:dd:d9:dd:c25:c25:94de:4b7f
1292c19:dd:d9:dd:c25:c25:94de:4b80/1282c19:dd:d9:dd:c25:c25:94de:4b80
1302c19:dd:d9:dd:c25:c25:94de:4b81/1282c19:dd:d9:dd:c25:c25:94de:4b81
1312c19:dd:d9:dd:c25:c25:94de:4b82/1282c19:dd:d9:dd:c25:c25:94de:4b82
1322c19:dd:d9:dd:c25:c25:94de:4b83/1282c19:dd:d9:dd:c25:c25:94de:4b83
1332c19:dd:d9:dd:c25:c25:94de:4b84/1282c19:dd:d9:dd:c25:c25:94de:4b84
1342c19:dd:d9:dd:c25:c25:94de:4b85/1282c19:dd:d9:dd:c25:c25:94de:4b85
1352c19:dd:d9:dd:c25:c25:94de:4b86/1282c19:dd:d9:dd:c25:c25:94de:4b86
1362c19:dd:d9:dd:c25:c25:94de:4b87/1282c19:dd:d9:dd:c25:c25:94de:4b87
1372c19:dd:d9:dd:c25:c25:94de:4b88/1282c19:dd:d9:dd:c25:c25:94de:4b88
1382c19:dd:d9:dd:c25:c25:94de:4b89/1282c19:dd:d9:dd:c25:c25:94de:4b89
1392c19:dd:d9:dd:c25:c25:94de:4b8a/1282c19:dd:d9:dd:c25:c25:94de:4b8a
1402c19:dd:d9:dd:c25:c25:94de:4b8b/1282c19:dd:d9:dd:c25:c25:94de:4b8b
1412c19:dd:d9:dd:c25:c25:94de:4b8c/1282c19:dd:d9:dd:c25:c25:94de:4b8c
1422c19:dd:d9:dd:c25:c25:94de:4b8d/1282c19:dd:d9:dd:c25:c25:94de:4b8d
1432c19:dd:d9:dd:c25:c25:94de:4b8e/1282c19:dd:d9:dd:c25:c25:94de:4b8e
1442c19:dd:d9:dd:c25:c25:94de:4b8f/1282c19:dd:d9:dd:c25:c25:94de:4b8f
1452c19:dd:d9:dd:c25:c25:94de:4b90/1282c19:dd:d9:dd:c25:c25:94de:4b90
1462c19:dd:d9:dd:c25:c25:94de:4b91/1282c19:dd:d9:dd:c25:c25:94de:4b91
1472c19:dd:d9:dd:c25:c25:94de:4b92/1282c19:dd:d9:dd:c25:c25:94de:4b92
1482c19:dd:d9:dd:c25:c25:94de:4b93/1282c19:dd:d9:dd:c25:c25:94de:4b93
1492c19:dd:d9:dd:c25:c25:94de:4b94/1282c19:dd:d9:dd:c25:c25:94de:4b94
1502c19:dd:d9:dd:c25:c25:94de:4b95/1282c19:dd:d9:dd:c25:c25:94de:4b95
1512c19:dd:d9:dd:c25:c25:94de:4b96/1282c19:dd:d9:dd:c25:c25:94de:4b96
1522c19:dd:d9:dd:c25:c25:94de:4b97/1282c19:dd:d9:dd:c25:c25:94de:4b97
1532c19:dd:d9:dd:c25:c25:94de:4b98/1282c19:dd:d9:dd:c25:c25:94de:4b98
1542c19:dd:d9:dd:c25:c25:94de:4b99/1282c19:dd:d9:dd:c25:c25:94de:4b99
1552c19:dd:d9:dd:c25:c25:94de:4b9a/1282c19:dd:d9:dd:c25:c25:94de:4b9a
1562c19:dd:d9:dd:c25:c25:94de:4b9b/1282c19:dd:d9:dd:c25:c25:94de:4b9b
1572c19:dd:d9:dd:c25:c25:94de:4b9c/1282c19:dd:d9:dd:c25:c25:94de:4b9c
1582c19:dd:d9:dd:c25:c25:94de:4b9d/1282c19:dd:d9:dd:c25:c25:94de:4b9d
1592c19:dd:d9:dd:c25:c25:94de:4b9e/1282c19:dd:d9:dd:c25:c25:94de:4b9e
1602c19:dd:d9:dd:c25:c25:94de:4b9f/1282c19:dd:d9:dd:c25:c25:94de:4b9f
1612c19:dd:d9:dd:c25:c25:94de:4ba0/1282c19:dd:d9:dd:c25:c25:94de:4ba0
1622c19:dd:d9:dd:c25:c25:94de:4ba1/1282c19:dd:d9:dd:c25:c25:94de:4ba1
1632c19:dd:d9:dd:c25:c25:94de:4ba2/1282c19:dd:d9:dd:c25:c25:94de:4ba2
1642c19:dd:d9:dd:c25:c25:94de:4ba3/1282c19:dd:d9:dd:c25:c25:94de:4ba3
1652c19:dd:d9:dd:c25:c25:94de:4ba4/1282c19:dd:d9:dd:c25:c25:94de:4ba4
1662c19:dd:d9:dd:c25:c25:94de:4ba5/1282c19:dd:d9:dd:c25:c25:94de:4ba5
1672c19:dd:d9:dd:c25:c25:94de:4ba6/1282c19:dd:d9:dd:c25:c25:94de:4ba6
1682c19:dd:d9:dd:c25:c25:94de:4ba7/1282c19:dd:d9:dd:c25:c25:94de:4ba7
1692c19:dd:d9:dd:c25:c25:94de:4ba8/1282c19:dd:d9:dd:c25:c25:94de:4ba8
1702c19:dd:d9:dd:c25:c25:94de:4ba9/1282c19:dd:d9:dd:c25:c25:94de:4ba9
1712c19:dd:d9:dd:c25:c25:94de:4baa/1282c19:dd:d9:dd:c25:c25:94de:4baa
1722c19:dd:d9:dd:c25:c25:94de:4bab/1282c19:dd:d9:dd:c25:c25:94de:4bab
1732c19:dd:d9:dd:c25:c25:94de:4bac/1282c19:dd:d9:dd:c25:c25:94de:4bac
1742c19:dd:d9:dd:c25:c25:94de:4bad/1282c19:dd:d9:dd:c25:c25:94de:4bad
1752c19:dd:d9:dd:c25:c25:94de:4bae/1282c19:dd:d9:dd:c25:c25:94de:4bae
1762c19:dd:d9:dd:c25:c25:94de:4baf/1282c19:dd:d9:dd:c25:c25:94de:4baf
1772c19:dd:d9:dd:c25:c25:94de:4bb0/1282c19:dd:d9:dd:c25:c25:94de:4bb0
1782c19:dd:d9:dd:c25:c25:94de:4bb1/1282c19:dd:d9:dd:c25:c25:94de:4bb1
1792c19:dd:d9:dd:c25:c25:94de:4bb2/1282c19:dd:d9:dd:c25:c25:94de:4bb2
1802c19:dd:d9:dd:c25:c25:94de:4bb3/1282c19:dd:d9:dd:c25:c25:94de:4bb3
1812c19:dd:d9:dd:c25:c25:94de:4bb4/1282c19:dd:d9:dd:c25:c25:94de:4bb4
1822c19:dd:d9:dd:c25:c25:94de:4bb5/1282c19:dd:d9:dd:c25:c25:94de:4bb5
1832c19:dd:d9:dd:c25:c25:94de:4bb6/1282c19:dd:d9:dd:c25:c25:94de:4bb6
1842c19:dd:d9:dd:c25:c25:94de:4bb7/1282c19:dd:d9:dd:c25:c25:94de:4bb7
1852c19:dd:d9:dd:c25:c25:94de:4bb8/1282c19:dd:d9:dd:c25:c25:94de:4bb8
1862c19:dd:d9:dd:c25:c25:94de:4bb9/1282c19:dd:d9:dd:c25:c25:94de:4bb9
1872c19:dd:d9:dd:c25:c25:94de:4bba/1282c19:dd:d9:dd:c25:c25:94de:4bba
1882c19:dd:d9:dd:c25:c25:94de:4bbb/1282c19:dd:d9:dd:c25:c25:94de:4bbb
1892c19:dd:d9:dd:c25:c25:94de:4bbc/1282c19:dd:d9:dd:c25:c25:94de:4bbc
1902c19:dd:d9:dd:c25:c25:94de:4bbd/1282c19:dd:d9:dd:c25:c25:94de:4bbd
1912c19:dd:d9:dd:c25:c25:94de:4bbe/1282c19:dd:d9:dd:c25:c25:94de:4bbe
1922c19:dd:d9:dd:c25:c25:94de:4bbf/1282c19:dd:d9:dd:c25:c25:94de:4bbf
1932c19:dd:d9:dd:c25:c25:94de:4bc0/1282c19:dd:d9:dd:c25:c25:94de:4bc0
1942c19:dd:d9:dd:c25:c25:94de:4bc1/1282c19:dd:d9:dd:c25:c25:94de:4bc1
1952c19:dd:d9:dd:c25:c25:94de:4bc2/1282c19:dd:d9:dd:c25:c25:94de:4bc2
1962c19:dd:d9:dd:c25:c25:94de:4bc3/1282c19:dd:d9:dd:c25:c25:94de:4bc3
1972c19:dd:d9:dd:c25:c25:94de:4bc4/1282c19:dd:d9:dd:c25:c25:94de:4bc4
1982c19:dd:d9:dd:c25:c25:94de:4bc5/1282c19:dd:d9:dd:c25:c25:94de:4bc5
1992c19:dd:d9:dd:c25:c25:94de:4bc6/1282c19:dd:d9:dd:c25:c25:94de:4bc6
2002c19:dd:d9:dd:c25:c25:94de:4bc7/1282c19:dd:d9:dd:c25:c25:94de:4bc7
2012c19:dd:d9:dd:c25:c25:94de:4bc8/1282c19:dd:d9:dd:c25:c25:94de:4bc8
2022c19:dd:d9:dd:c25:c25:94de:4bc9/1282c19:dd:d9:dd:c25:c25:94de:4bc9
2032c19:dd:d9:dd:c25:c25:94de:4bca/1282c19:dd:d9:dd:c25:c25:94de:4bca
2042c19:dd:d9:dd:c25:c25:94de:4bcb/1282c19:dd:d9:dd:c25:c25:94de:4bcb
2052c19:dd:d9:dd:c25:c25:94de:4bcc/1282c19:dd:d9:dd:c25:c25:94de:4bcc
2062c19:dd:d9:dd:c25:c25:94de:4bcd/1282c19:dd:d9:dd:c25:c25:94de:4bcd
2072c19:dd:d9:dd:c25:c25:94de:4bce/1282c19:dd:d9:dd:c25:c25:94de:4bce
2082c19:dd:d9:dd:c25:c25:94de:4bcf/1282c19:dd:d9:dd:c25:c25:94de:4bcf
2092c19:dd:d9:dd:c25:c25:94de:4bd0/1282c19:dd:d9:dd:c25:c25:94de:4bd0
2102c19:dd:d9:dd:c25:c25:94de:4bd1/1282c19:dd:d9:dd:c25:c25:94de:4bd1
2112c19:dd:d9:dd:c25:c25:94de:4bd2/1282c19:dd:d9:dd:c25:c25:94de:4bd2
2122c19:dd:d9:dd:c25:c25:94de:4bd3/1282c19:dd:d9:dd:c25:c25:94de:4bd3
2132c19:dd:d9:dd:c25:c25:94de:4bd4/1282c19:dd:d9:dd:c25:c25:94de:4bd4
2142c19:dd:d9:dd:c25:c25:94de:4bd5/1282c19:dd:d9:dd:c25:c25:94de:4bd5
2152c19:dd:d9:dd:c25:c25:94de:4bd6/1282c19:dd:d9:dd:c25:c25:94de:4bd6
2162c19:dd:d9:dd:c25:c25:94de:4bd7/1282c19:dd:d9:dd:c25:c25:94de:4bd7
2172c19:dd:d9:dd:c25:c25:94de:4bd8/1282c19:dd:d9:dd:c25:c25:94de:4bd8
2182c19:dd:d9:dd:c25:c25:94de:4bd9/1282c19:dd:d9:dd:c25:c25:94de:4bd9
2192c19:dd:d9:dd:c25:c25:94de:4bda/1282c19:dd:d9:dd:c25:c25:94de:4bda
2202c19:dd:d9:dd:c25:c25:94de:4bdb/1282c19:dd:d9:dd:c25:c25:94de:4bdb
2212c19:dd:d9:dd:c25:c25:94de:4bdc/1282c19:dd:d9:dd:c25:c25:94de:4bdc
2222c19:dd:d9:dd:c25:c25:94de:4bdd/1282c19:dd:d9:dd:c25:c25:94de:4bdd
2232c19:dd:d9:dd:c25:c25:94de:4bde/1282c19:dd:d9:dd:c25:c25:94de:4bde
2242c19:dd:d9:dd:c25:c25:94de:4bdf/1282c19:dd:d9:dd:c25:c25:94de:4bdf
2252c19:dd:d9:dd:c25:c25:94de:4be0/1282c19:dd:d9:dd:c25:c25:94de:4be0
2262c19:dd:d9:dd:c25:c25:94de:4be1/1282c19:dd:d9:dd:c25:c25:94de:4be1
2272c19:dd:d9:dd:c25:c25:94de:4be2/1282c19:dd:d9:dd:c25:c25:94de:4be2
2282c19:dd:d9:dd:c25:c25:94de:4be3/1282c19:dd:d9:dd:c25:c25:94de:4be3
2292c19:dd:d9:dd:c25:c25:94de:4be4/1282c19:dd:d9:dd:c25:c25:94de:4be4
2302c19:dd:d9:dd:c25:c25:94de:4be5/1282c19:dd:d9:dd:c25:c25:94de:4be5
2312c19:dd:d9:dd:c25:c25:94de:4be6/1282c19:dd:d9:dd:c25:c25:94de:4be6
2322c19:dd:d9:dd:c25:c25:94de:4be7/1282c19:dd:d9:dd:c25:c25:94de:4be7
2332c19:dd:d9:dd:c25:c25:94de:4be8/1282c19:dd:d9:dd:c25:c25:94de:4be8
2342c19:dd:d9:dd:c25:c25:94de:4be9/1282c19:dd:d9:dd:c25:c25:94de:4be9
2352c19:dd:d9:dd:c25:c25:94de:4bea/1282c19:dd:d9:dd:c25:c25:94de:4bea
2362c19:dd:d9:dd:c25:c25:94de:4beb/1282c19:dd:d9:dd:c25:c25:94de:4beb
2372c19:dd:d9:dd:c25:c25:94de:4bec/1282c19:dd:d9:dd:c25:c25:94de:4bec
2382c19:dd:d9:dd:c25:c25:94de:4bed/1282c19:dd:d9:dd:c25:c25:94de:4bed
2392c19:dd:d9:dd:c25:c25:94de:4bee/1282c19:dd:d9:dd:c25:c25:94de:4bee
2402c19:dd:d9:dd:c25:c25:94de:4bef/1282c19:dd:d9:dd:c25:c25:94de:4bef
2412c19:dd:d9:dd:c25:c25:94de:4bf0/1282c19:dd:d9:dd:c25:c25:94de:4bf0
2422c19:dd:d9:dd:c25:c25:94de:4bf1/1282c19:dd:d9:dd:c25:c25:94de:4bf1
2432c19:dd:d9:dd:c25:c25:94de:4bf2/1282c19:dd:d9:dd:c25:c25:94de:4bf2
2442c19:dd:d9:dd:c25:c25:94de:4bf3/1282c19:dd:d9:dd:c25:c25:94de:4bf3
2452c19:dd:d9:dd:c25:c25:94de:4bf4/1282c19:dd:d9:dd:c25:c25:94de:4bf4
2462c19:dd:d9:dd:c25:c25:94de:4bf5/1282c19:dd:d9:dd:c25:c25:94de:4bf5
2472c19:dd:d9:dd:c25:c25:94de:4bf6/1282c19:dd:d9:dd:c25:c25:94de:4bf6
2482c19:dd:d9:dd:c25:c25:94de:4bf7/1282c19:dd:d9:dd:c25:c25:94de:4bf7
2492c19:dd:d9:dd:c25:c25:94de:4bf8/1282c19:dd:d9:dd:c25:c25:94de:4bf8
2502c19:dd:d9:dd:c25:c25:94de:4bf9/1282c19:dd:d9:dd:c25:c25:94de:4bf9
2512c19:dd:d9:dd:c25:c25:94de:4bfa/1282c19:dd:d9:dd:c25:c25:94de:4bfa
2522c19:dd:d9:dd:c25:c25:94de:4bfb/1282c19:dd:d9:dd:c25:c25:94de:4bfb
2532c19:dd:d9:dd:c25:c25:94de:4bfc/1282c19:dd:d9:dd:c25:c25:94de:4bfc
2542c19:dd:d9:dd:c25:c25:94de:4bfd/1282c19:dd:d9:dd:c25:c25:94de:4bfd
2552c19:dd:d9:dd:c25:c25:94de:4bfe/1282c19:dd:d9:dd:c25:c25:94de:4bfe
2562c19:dd:d9:dd:c25:c25:94de:4bff/1282c19:dd:d9:dd:c25:c25:94de:4bff

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.