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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:c25:c25d:dd:dd:dd:7b00/120
First address
2c19:dd:c25:c25d:dd:dd:dd:7b00
Last address
2c19:dd:c25:c25d:dd:dd:dd:7bff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:7b00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
b.7.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.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:c25:c25d:dd:dd:dd:7b00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:7b00/1282c19:dd:c25:c25d:dd:dd:dd:7b00
22c19:dd:c25:c25d:dd:dd:dd:7b01/1282c19:dd:c25:c25d:dd:dd:dd:7b01
32c19:dd:c25:c25d:dd:dd:dd:7b02/1282c19:dd:c25:c25d:dd:dd:dd:7b02
42c19:dd:c25:c25d:dd:dd:dd:7b03/1282c19:dd:c25:c25d:dd:dd:dd:7b03
52c19:dd:c25:c25d:dd:dd:dd:7b04/1282c19:dd:c25:c25d:dd:dd:dd:7b04
62c19:dd:c25:c25d:dd:dd:dd:7b05/1282c19:dd:c25:c25d:dd:dd:dd:7b05
72c19:dd:c25:c25d:dd:dd:dd:7b06/1282c19:dd:c25:c25d:dd:dd:dd:7b06
82c19:dd:c25:c25d:dd:dd:dd:7b07/1282c19:dd:c25:c25d:dd:dd:dd:7b07
92c19:dd:c25:c25d:dd:dd:dd:7b08/1282c19:dd:c25:c25d:dd:dd:dd:7b08
102c19:dd:c25:c25d:dd:dd:dd:7b09/1282c19:dd:c25:c25d:dd:dd:dd:7b09
112c19:dd:c25:c25d:dd:dd:dd:7b0a/1282c19:dd:c25:c25d:dd:dd:dd:7b0a
122c19:dd:c25:c25d:dd:dd:dd:7b0b/1282c19:dd:c25:c25d:dd:dd:dd:7b0b
132c19:dd:c25:c25d:dd:dd:dd:7b0c/1282c19:dd:c25:c25d:dd:dd:dd:7b0c
142c19:dd:c25:c25d:dd:dd:dd:7b0d/1282c19:dd:c25:c25d:dd:dd:dd:7b0d
152c19:dd:c25:c25d:dd:dd:dd:7b0e/1282c19:dd:c25:c25d:dd:dd:dd:7b0e
162c19:dd:c25:c25d:dd:dd:dd:7b0f/1282c19:dd:c25:c25d:dd:dd:dd:7b0f
172c19:dd:c25:c25d:dd:dd:dd:7b10/1282c19:dd:c25:c25d:dd:dd:dd:7b10
182c19:dd:c25:c25d:dd:dd:dd:7b11/1282c19:dd:c25:c25d:dd:dd:dd:7b11
192c19:dd:c25:c25d:dd:dd:dd:7b12/1282c19:dd:c25:c25d:dd:dd:dd:7b12
202c19:dd:c25:c25d:dd:dd:dd:7b13/1282c19:dd:c25:c25d:dd:dd:dd:7b13
212c19:dd:c25:c25d:dd:dd:dd:7b14/1282c19:dd:c25:c25d:dd:dd:dd:7b14
222c19:dd:c25:c25d:dd:dd:dd:7b15/1282c19:dd:c25:c25d:dd:dd:dd:7b15
232c19:dd:c25:c25d:dd:dd:dd:7b16/1282c19:dd:c25:c25d:dd:dd:dd:7b16
242c19:dd:c25:c25d:dd:dd:dd:7b17/1282c19:dd:c25:c25d:dd:dd:dd:7b17
252c19:dd:c25:c25d:dd:dd:dd:7b18/1282c19:dd:c25:c25d:dd:dd:dd:7b18
262c19:dd:c25:c25d:dd:dd:dd:7b19/1282c19:dd:c25:c25d:dd:dd:dd:7b19
272c19:dd:c25:c25d:dd:dd:dd:7b1a/1282c19:dd:c25:c25d:dd:dd:dd:7b1a
282c19:dd:c25:c25d:dd:dd:dd:7b1b/1282c19:dd:c25:c25d:dd:dd:dd:7b1b
292c19:dd:c25:c25d:dd:dd:dd:7b1c/1282c19:dd:c25:c25d:dd:dd:dd:7b1c
302c19:dd:c25:c25d:dd:dd:dd:7b1d/1282c19:dd:c25:c25d:dd:dd:dd:7b1d
312c19:dd:c25:c25d:dd:dd:dd:7b1e/1282c19:dd:c25:c25d:dd:dd:dd:7b1e
322c19:dd:c25:c25d:dd:dd:dd:7b1f/1282c19:dd:c25:c25d:dd:dd:dd:7b1f
332c19:dd:c25:c25d:dd:dd:dd:7b20/1282c19:dd:c25:c25d:dd:dd:dd:7b20
342c19:dd:c25:c25d:dd:dd:dd:7b21/1282c19:dd:c25:c25d:dd:dd:dd:7b21
352c19:dd:c25:c25d:dd:dd:dd:7b22/1282c19:dd:c25:c25d:dd:dd:dd:7b22
362c19:dd:c25:c25d:dd:dd:dd:7b23/1282c19:dd:c25:c25d:dd:dd:dd:7b23
372c19:dd:c25:c25d:dd:dd:dd:7b24/1282c19:dd:c25:c25d:dd:dd:dd:7b24
382c19:dd:c25:c25d:dd:dd:dd:7b25/1282c19:dd:c25:c25d:dd:dd:dd:7b25
392c19:dd:c25:c25d:dd:dd:dd:7b26/1282c19:dd:c25:c25d:dd:dd:dd:7b26
402c19:dd:c25:c25d:dd:dd:dd:7b27/1282c19:dd:c25:c25d:dd:dd:dd:7b27
412c19:dd:c25:c25d:dd:dd:dd:7b28/1282c19:dd:c25:c25d:dd:dd:dd:7b28
422c19:dd:c25:c25d:dd:dd:dd:7b29/1282c19:dd:c25:c25d:dd:dd:dd:7b29
432c19:dd:c25:c25d:dd:dd:dd:7b2a/1282c19:dd:c25:c25d:dd:dd:dd:7b2a
442c19:dd:c25:c25d:dd:dd:dd:7b2b/1282c19:dd:c25:c25d:dd:dd:dd:7b2b
452c19:dd:c25:c25d:dd:dd:dd:7b2c/1282c19:dd:c25:c25d:dd:dd:dd:7b2c
462c19:dd:c25:c25d:dd:dd:dd:7b2d/1282c19:dd:c25:c25d:dd:dd:dd:7b2d
472c19:dd:c25:c25d:dd:dd:dd:7b2e/1282c19:dd:c25:c25d:dd:dd:dd:7b2e
482c19:dd:c25:c25d:dd:dd:dd:7b2f/1282c19:dd:c25:c25d:dd:dd:dd:7b2f
492c19:dd:c25:c25d:dd:dd:dd:7b30/1282c19:dd:c25:c25d:dd:dd:dd:7b30
502c19:dd:c25:c25d:dd:dd:dd:7b31/1282c19:dd:c25:c25d:dd:dd:dd:7b31
512c19:dd:c25:c25d:dd:dd:dd:7b32/1282c19:dd:c25:c25d:dd:dd:dd:7b32
522c19:dd:c25:c25d:dd:dd:dd:7b33/1282c19:dd:c25:c25d:dd:dd:dd:7b33
532c19:dd:c25:c25d:dd:dd:dd:7b34/1282c19:dd:c25:c25d:dd:dd:dd:7b34
542c19:dd:c25:c25d:dd:dd:dd:7b35/1282c19:dd:c25:c25d:dd:dd:dd:7b35
552c19:dd:c25:c25d:dd:dd:dd:7b36/1282c19:dd:c25:c25d:dd:dd:dd:7b36
562c19:dd:c25:c25d:dd:dd:dd:7b37/1282c19:dd:c25:c25d:dd:dd:dd:7b37
572c19:dd:c25:c25d:dd:dd:dd:7b38/1282c19:dd:c25:c25d:dd:dd:dd:7b38
582c19:dd:c25:c25d:dd:dd:dd:7b39/1282c19:dd:c25:c25d:dd:dd:dd:7b39
592c19:dd:c25:c25d:dd:dd:dd:7b3a/1282c19:dd:c25:c25d:dd:dd:dd:7b3a
602c19:dd:c25:c25d:dd:dd:dd:7b3b/1282c19:dd:c25:c25d:dd:dd:dd:7b3b
612c19:dd:c25:c25d:dd:dd:dd:7b3c/1282c19:dd:c25:c25d:dd:dd:dd:7b3c
622c19:dd:c25:c25d:dd:dd:dd:7b3d/1282c19:dd:c25:c25d:dd:dd:dd:7b3d
632c19:dd:c25:c25d:dd:dd:dd:7b3e/1282c19:dd:c25:c25d:dd:dd:dd:7b3e
642c19:dd:c25:c25d:dd:dd:dd:7b3f/1282c19:dd:c25:c25d:dd:dd:dd:7b3f
652c19:dd:c25:c25d:dd:dd:dd:7b40/1282c19:dd:c25:c25d:dd:dd:dd:7b40
662c19:dd:c25:c25d:dd:dd:dd:7b41/1282c19:dd:c25:c25d:dd:dd:dd:7b41
672c19:dd:c25:c25d:dd:dd:dd:7b42/1282c19:dd:c25:c25d:dd:dd:dd:7b42
682c19:dd:c25:c25d:dd:dd:dd:7b43/1282c19:dd:c25:c25d:dd:dd:dd:7b43
692c19:dd:c25:c25d:dd:dd:dd:7b44/1282c19:dd:c25:c25d:dd:dd:dd:7b44
702c19:dd:c25:c25d:dd:dd:dd:7b45/1282c19:dd:c25:c25d:dd:dd:dd:7b45
712c19:dd:c25:c25d:dd:dd:dd:7b46/1282c19:dd:c25:c25d:dd:dd:dd:7b46
722c19:dd:c25:c25d:dd:dd:dd:7b47/1282c19:dd:c25:c25d:dd:dd:dd:7b47
732c19:dd:c25:c25d:dd:dd:dd:7b48/1282c19:dd:c25:c25d:dd:dd:dd:7b48
742c19:dd:c25:c25d:dd:dd:dd:7b49/1282c19:dd:c25:c25d:dd:dd:dd:7b49
752c19:dd:c25:c25d:dd:dd:dd:7b4a/1282c19:dd:c25:c25d:dd:dd:dd:7b4a
762c19:dd:c25:c25d:dd:dd:dd:7b4b/1282c19:dd:c25:c25d:dd:dd:dd:7b4b
772c19:dd:c25:c25d:dd:dd:dd:7b4c/1282c19:dd:c25:c25d:dd:dd:dd:7b4c
782c19:dd:c25:c25d:dd:dd:dd:7b4d/1282c19:dd:c25:c25d:dd:dd:dd:7b4d
792c19:dd:c25:c25d:dd:dd:dd:7b4e/1282c19:dd:c25:c25d:dd:dd:dd:7b4e
802c19:dd:c25:c25d:dd:dd:dd:7b4f/1282c19:dd:c25:c25d:dd:dd:dd:7b4f
812c19:dd:c25:c25d:dd:dd:dd:7b50/1282c19:dd:c25:c25d:dd:dd:dd:7b50
822c19:dd:c25:c25d:dd:dd:dd:7b51/1282c19:dd:c25:c25d:dd:dd:dd:7b51
832c19:dd:c25:c25d:dd:dd:dd:7b52/1282c19:dd:c25:c25d:dd:dd:dd:7b52
842c19:dd:c25:c25d:dd:dd:dd:7b53/1282c19:dd:c25:c25d:dd:dd:dd:7b53
852c19:dd:c25:c25d:dd:dd:dd:7b54/1282c19:dd:c25:c25d:dd:dd:dd:7b54
862c19:dd:c25:c25d:dd:dd:dd:7b55/1282c19:dd:c25:c25d:dd:dd:dd:7b55
872c19:dd:c25:c25d:dd:dd:dd:7b56/1282c19:dd:c25:c25d:dd:dd:dd:7b56
882c19:dd:c25:c25d:dd:dd:dd:7b57/1282c19:dd:c25:c25d:dd:dd:dd:7b57
892c19:dd:c25:c25d:dd:dd:dd:7b58/1282c19:dd:c25:c25d:dd:dd:dd:7b58
902c19:dd:c25:c25d:dd:dd:dd:7b59/1282c19:dd:c25:c25d:dd:dd:dd:7b59
912c19:dd:c25:c25d:dd:dd:dd:7b5a/1282c19:dd:c25:c25d:dd:dd:dd:7b5a
922c19:dd:c25:c25d:dd:dd:dd:7b5b/1282c19:dd:c25:c25d:dd:dd:dd:7b5b
932c19:dd:c25:c25d:dd:dd:dd:7b5c/1282c19:dd:c25:c25d:dd:dd:dd:7b5c
942c19:dd:c25:c25d:dd:dd:dd:7b5d/1282c19:dd:c25:c25d:dd:dd:dd:7b5d
952c19:dd:c25:c25d:dd:dd:dd:7b5e/1282c19:dd:c25:c25d:dd:dd:dd:7b5e
962c19:dd:c25:c25d:dd:dd:dd:7b5f/1282c19:dd:c25:c25d:dd:dd:dd:7b5f
972c19:dd:c25:c25d:dd:dd:dd:7b60/1282c19:dd:c25:c25d:dd:dd:dd:7b60
982c19:dd:c25:c25d:dd:dd:dd:7b61/1282c19:dd:c25:c25d:dd:dd:dd:7b61
992c19:dd:c25:c25d:dd:dd:dd:7b62/1282c19:dd:c25:c25d:dd:dd:dd:7b62
1002c19:dd:c25:c25d:dd:dd:dd:7b63/1282c19:dd:c25:c25d:dd:dd:dd:7b63
1012c19:dd:c25:c25d:dd:dd:dd:7b64/1282c19:dd:c25:c25d:dd:dd:dd:7b64
1022c19:dd:c25:c25d:dd:dd:dd:7b65/1282c19:dd:c25:c25d:dd:dd:dd:7b65
1032c19:dd:c25:c25d:dd:dd:dd:7b66/1282c19:dd:c25:c25d:dd:dd:dd:7b66
1042c19:dd:c25:c25d:dd:dd:dd:7b67/1282c19:dd:c25:c25d:dd:dd:dd:7b67
1052c19:dd:c25:c25d:dd:dd:dd:7b68/1282c19:dd:c25:c25d:dd:dd:dd:7b68
1062c19:dd:c25:c25d:dd:dd:dd:7b69/1282c19:dd:c25:c25d:dd:dd:dd:7b69
1072c19:dd:c25:c25d:dd:dd:dd:7b6a/1282c19:dd:c25:c25d:dd:dd:dd:7b6a
1082c19:dd:c25:c25d:dd:dd:dd:7b6b/1282c19:dd:c25:c25d:dd:dd:dd:7b6b
1092c19:dd:c25:c25d:dd:dd:dd:7b6c/1282c19:dd:c25:c25d:dd:dd:dd:7b6c
1102c19:dd:c25:c25d:dd:dd:dd:7b6d/1282c19:dd:c25:c25d:dd:dd:dd:7b6d
1112c19:dd:c25:c25d:dd:dd:dd:7b6e/1282c19:dd:c25:c25d:dd:dd:dd:7b6e
1122c19:dd:c25:c25d:dd:dd:dd:7b6f/1282c19:dd:c25:c25d:dd:dd:dd:7b6f
1132c19:dd:c25:c25d:dd:dd:dd:7b70/1282c19:dd:c25:c25d:dd:dd:dd:7b70
1142c19:dd:c25:c25d:dd:dd:dd:7b71/1282c19:dd:c25:c25d:dd:dd:dd:7b71
1152c19:dd:c25:c25d:dd:dd:dd:7b72/1282c19:dd:c25:c25d:dd:dd:dd:7b72
1162c19:dd:c25:c25d:dd:dd:dd:7b73/1282c19:dd:c25:c25d:dd:dd:dd:7b73
1172c19:dd:c25:c25d:dd:dd:dd:7b74/1282c19:dd:c25:c25d:dd:dd:dd:7b74
1182c19:dd:c25:c25d:dd:dd:dd:7b75/1282c19:dd:c25:c25d:dd:dd:dd:7b75
1192c19:dd:c25:c25d:dd:dd:dd:7b76/1282c19:dd:c25:c25d:dd:dd:dd:7b76
1202c19:dd:c25:c25d:dd:dd:dd:7b77/1282c19:dd:c25:c25d:dd:dd:dd:7b77
1212c19:dd:c25:c25d:dd:dd:dd:7b78/1282c19:dd:c25:c25d:dd:dd:dd:7b78
1222c19:dd:c25:c25d:dd:dd:dd:7b79/1282c19:dd:c25:c25d:dd:dd:dd:7b79
1232c19:dd:c25:c25d:dd:dd:dd:7b7a/1282c19:dd:c25:c25d:dd:dd:dd:7b7a
1242c19:dd:c25:c25d:dd:dd:dd:7b7b/1282c19:dd:c25:c25d:dd:dd:dd:7b7b
1252c19:dd:c25:c25d:dd:dd:dd:7b7c/1282c19:dd:c25:c25d:dd:dd:dd:7b7c
1262c19:dd:c25:c25d:dd:dd:dd:7b7d/1282c19:dd:c25:c25d:dd:dd:dd:7b7d
1272c19:dd:c25:c25d:dd:dd:dd:7b7e/1282c19:dd:c25:c25d:dd:dd:dd:7b7e
1282c19:dd:c25:c25d:dd:dd:dd:7b7f/1282c19:dd:c25:c25d:dd:dd:dd:7b7f
1292c19:dd:c25:c25d:dd:dd:dd:7b80/1282c19:dd:c25:c25d:dd:dd:dd:7b80
1302c19:dd:c25:c25d:dd:dd:dd:7b81/1282c19:dd:c25:c25d:dd:dd:dd:7b81
1312c19:dd:c25:c25d:dd:dd:dd:7b82/1282c19:dd:c25:c25d:dd:dd:dd:7b82
1322c19:dd:c25:c25d:dd:dd:dd:7b83/1282c19:dd:c25:c25d:dd:dd:dd:7b83
1332c19:dd:c25:c25d:dd:dd:dd:7b84/1282c19:dd:c25:c25d:dd:dd:dd:7b84
1342c19:dd:c25:c25d:dd:dd:dd:7b85/1282c19:dd:c25:c25d:dd:dd:dd:7b85
1352c19:dd:c25:c25d:dd:dd:dd:7b86/1282c19:dd:c25:c25d:dd:dd:dd:7b86
1362c19:dd:c25:c25d:dd:dd:dd:7b87/1282c19:dd:c25:c25d:dd:dd:dd:7b87
1372c19:dd:c25:c25d:dd:dd:dd:7b88/1282c19:dd:c25:c25d:dd:dd:dd:7b88
1382c19:dd:c25:c25d:dd:dd:dd:7b89/1282c19:dd:c25:c25d:dd:dd:dd:7b89
1392c19:dd:c25:c25d:dd:dd:dd:7b8a/1282c19:dd:c25:c25d:dd:dd:dd:7b8a
1402c19:dd:c25:c25d:dd:dd:dd:7b8b/1282c19:dd:c25:c25d:dd:dd:dd:7b8b
1412c19:dd:c25:c25d:dd:dd:dd:7b8c/1282c19:dd:c25:c25d:dd:dd:dd:7b8c
1422c19:dd:c25:c25d:dd:dd:dd:7b8d/1282c19:dd:c25:c25d:dd:dd:dd:7b8d
1432c19:dd:c25:c25d:dd:dd:dd:7b8e/1282c19:dd:c25:c25d:dd:dd:dd:7b8e
1442c19:dd:c25:c25d:dd:dd:dd:7b8f/1282c19:dd:c25:c25d:dd:dd:dd:7b8f
1452c19:dd:c25:c25d:dd:dd:dd:7b90/1282c19:dd:c25:c25d:dd:dd:dd:7b90
1462c19:dd:c25:c25d:dd:dd:dd:7b91/1282c19:dd:c25:c25d:dd:dd:dd:7b91
1472c19:dd:c25:c25d:dd:dd:dd:7b92/1282c19:dd:c25:c25d:dd:dd:dd:7b92
1482c19:dd:c25:c25d:dd:dd:dd:7b93/1282c19:dd:c25:c25d:dd:dd:dd:7b93
1492c19:dd:c25:c25d:dd:dd:dd:7b94/1282c19:dd:c25:c25d:dd:dd:dd:7b94
1502c19:dd:c25:c25d:dd:dd:dd:7b95/1282c19:dd:c25:c25d:dd:dd:dd:7b95
1512c19:dd:c25:c25d:dd:dd:dd:7b96/1282c19:dd:c25:c25d:dd:dd:dd:7b96
1522c19:dd:c25:c25d:dd:dd:dd:7b97/1282c19:dd:c25:c25d:dd:dd:dd:7b97
1532c19:dd:c25:c25d:dd:dd:dd:7b98/1282c19:dd:c25:c25d:dd:dd:dd:7b98
1542c19:dd:c25:c25d:dd:dd:dd:7b99/1282c19:dd:c25:c25d:dd:dd:dd:7b99
1552c19:dd:c25:c25d:dd:dd:dd:7b9a/1282c19:dd:c25:c25d:dd:dd:dd:7b9a
1562c19:dd:c25:c25d:dd:dd:dd:7b9b/1282c19:dd:c25:c25d:dd:dd:dd:7b9b
1572c19:dd:c25:c25d:dd:dd:dd:7b9c/1282c19:dd:c25:c25d:dd:dd:dd:7b9c
1582c19:dd:c25:c25d:dd:dd:dd:7b9d/1282c19:dd:c25:c25d:dd:dd:dd:7b9d
1592c19:dd:c25:c25d:dd:dd:dd:7b9e/1282c19:dd:c25:c25d:dd:dd:dd:7b9e
1602c19:dd:c25:c25d:dd:dd:dd:7b9f/1282c19:dd:c25:c25d:dd:dd:dd:7b9f
1612c19:dd:c25:c25d:dd:dd:dd:7ba0/1282c19:dd:c25:c25d:dd:dd:dd:7ba0
1622c19:dd:c25:c25d:dd:dd:dd:7ba1/1282c19:dd:c25:c25d:dd:dd:dd:7ba1
1632c19:dd:c25:c25d:dd:dd:dd:7ba2/1282c19:dd:c25:c25d:dd:dd:dd:7ba2
1642c19:dd:c25:c25d:dd:dd:dd:7ba3/1282c19:dd:c25:c25d:dd:dd:dd:7ba3
1652c19:dd:c25:c25d:dd:dd:dd:7ba4/1282c19:dd:c25:c25d:dd:dd:dd:7ba4
1662c19:dd:c25:c25d:dd:dd:dd:7ba5/1282c19:dd:c25:c25d:dd:dd:dd:7ba5
1672c19:dd:c25:c25d:dd:dd:dd:7ba6/1282c19:dd:c25:c25d:dd:dd:dd:7ba6
1682c19:dd:c25:c25d:dd:dd:dd:7ba7/1282c19:dd:c25:c25d:dd:dd:dd:7ba7
1692c19:dd:c25:c25d:dd:dd:dd:7ba8/1282c19:dd:c25:c25d:dd:dd:dd:7ba8
1702c19:dd:c25:c25d:dd:dd:dd:7ba9/1282c19:dd:c25:c25d:dd:dd:dd:7ba9
1712c19:dd:c25:c25d:dd:dd:dd:7baa/1282c19:dd:c25:c25d:dd:dd:dd:7baa
1722c19:dd:c25:c25d:dd:dd:dd:7bab/1282c19:dd:c25:c25d:dd:dd:dd:7bab
1732c19:dd:c25:c25d:dd:dd:dd:7bac/1282c19:dd:c25:c25d:dd:dd:dd:7bac
1742c19:dd:c25:c25d:dd:dd:dd:7bad/1282c19:dd:c25:c25d:dd:dd:dd:7bad
1752c19:dd:c25:c25d:dd:dd:dd:7bae/1282c19:dd:c25:c25d:dd:dd:dd:7bae
1762c19:dd:c25:c25d:dd:dd:dd:7baf/1282c19:dd:c25:c25d:dd:dd:dd:7baf
1772c19:dd:c25:c25d:dd:dd:dd:7bb0/1282c19:dd:c25:c25d:dd:dd:dd:7bb0
1782c19:dd:c25:c25d:dd:dd:dd:7bb1/1282c19:dd:c25:c25d:dd:dd:dd:7bb1
1792c19:dd:c25:c25d:dd:dd:dd:7bb2/1282c19:dd:c25:c25d:dd:dd:dd:7bb2
1802c19:dd:c25:c25d:dd:dd:dd:7bb3/1282c19:dd:c25:c25d:dd:dd:dd:7bb3
1812c19:dd:c25:c25d:dd:dd:dd:7bb4/1282c19:dd:c25:c25d:dd:dd:dd:7bb4
1822c19:dd:c25:c25d:dd:dd:dd:7bb5/1282c19:dd:c25:c25d:dd:dd:dd:7bb5
1832c19:dd:c25:c25d:dd:dd:dd:7bb6/1282c19:dd:c25:c25d:dd:dd:dd:7bb6
1842c19:dd:c25:c25d:dd:dd:dd:7bb7/1282c19:dd:c25:c25d:dd:dd:dd:7bb7
1852c19:dd:c25:c25d:dd:dd:dd:7bb8/1282c19:dd:c25:c25d:dd:dd:dd:7bb8
1862c19:dd:c25:c25d:dd:dd:dd:7bb9/1282c19:dd:c25:c25d:dd:dd:dd:7bb9
1872c19:dd:c25:c25d:dd:dd:dd:7bba/1282c19:dd:c25:c25d:dd:dd:dd:7bba
1882c19:dd:c25:c25d:dd:dd:dd:7bbb/1282c19:dd:c25:c25d:dd:dd:dd:7bbb
1892c19:dd:c25:c25d:dd:dd:dd:7bbc/1282c19:dd:c25:c25d:dd:dd:dd:7bbc
1902c19:dd:c25:c25d:dd:dd:dd:7bbd/1282c19:dd:c25:c25d:dd:dd:dd:7bbd
1912c19:dd:c25:c25d:dd:dd:dd:7bbe/1282c19:dd:c25:c25d:dd:dd:dd:7bbe
1922c19:dd:c25:c25d:dd:dd:dd:7bbf/1282c19:dd:c25:c25d:dd:dd:dd:7bbf
1932c19:dd:c25:c25d:dd:dd:dd:7bc0/1282c19:dd:c25:c25d:dd:dd:dd:7bc0
1942c19:dd:c25:c25d:dd:dd:dd:7bc1/1282c19:dd:c25:c25d:dd:dd:dd:7bc1
1952c19:dd:c25:c25d:dd:dd:dd:7bc2/1282c19:dd:c25:c25d:dd:dd:dd:7bc2
1962c19:dd:c25:c25d:dd:dd:dd:7bc3/1282c19:dd:c25:c25d:dd:dd:dd:7bc3
1972c19:dd:c25:c25d:dd:dd:dd:7bc4/1282c19:dd:c25:c25d:dd:dd:dd:7bc4
1982c19:dd:c25:c25d:dd:dd:dd:7bc5/1282c19:dd:c25:c25d:dd:dd:dd:7bc5
1992c19:dd:c25:c25d:dd:dd:dd:7bc6/1282c19:dd:c25:c25d:dd:dd:dd:7bc6
2002c19:dd:c25:c25d:dd:dd:dd:7bc7/1282c19:dd:c25:c25d:dd:dd:dd:7bc7
2012c19:dd:c25:c25d:dd:dd:dd:7bc8/1282c19:dd:c25:c25d:dd:dd:dd:7bc8
2022c19:dd:c25:c25d:dd:dd:dd:7bc9/1282c19:dd:c25:c25d:dd:dd:dd:7bc9
2032c19:dd:c25:c25d:dd:dd:dd:7bca/1282c19:dd:c25:c25d:dd:dd:dd:7bca
2042c19:dd:c25:c25d:dd:dd:dd:7bcb/1282c19:dd:c25:c25d:dd:dd:dd:7bcb
2052c19:dd:c25:c25d:dd:dd:dd:7bcc/1282c19:dd:c25:c25d:dd:dd:dd:7bcc
2062c19:dd:c25:c25d:dd:dd:dd:7bcd/1282c19:dd:c25:c25d:dd:dd:dd:7bcd
2072c19:dd:c25:c25d:dd:dd:dd:7bce/1282c19:dd:c25:c25d:dd:dd:dd:7bce
2082c19:dd:c25:c25d:dd:dd:dd:7bcf/1282c19:dd:c25:c25d:dd:dd:dd:7bcf
2092c19:dd:c25:c25d:dd:dd:dd:7bd0/1282c19:dd:c25:c25d:dd:dd:dd:7bd0
2102c19:dd:c25:c25d:dd:dd:dd:7bd1/1282c19:dd:c25:c25d:dd:dd:dd:7bd1
2112c19:dd:c25:c25d:dd:dd:dd:7bd2/1282c19:dd:c25:c25d:dd:dd:dd:7bd2
2122c19:dd:c25:c25d:dd:dd:dd:7bd3/1282c19:dd:c25:c25d:dd:dd:dd:7bd3
2132c19:dd:c25:c25d:dd:dd:dd:7bd4/1282c19:dd:c25:c25d:dd:dd:dd:7bd4
2142c19:dd:c25:c25d:dd:dd:dd:7bd5/1282c19:dd:c25:c25d:dd:dd:dd:7bd5
2152c19:dd:c25:c25d:dd:dd:dd:7bd6/1282c19:dd:c25:c25d:dd:dd:dd:7bd6
2162c19:dd:c25:c25d:dd:dd:dd:7bd7/1282c19:dd:c25:c25d:dd:dd:dd:7bd7
2172c19:dd:c25:c25d:dd:dd:dd:7bd8/1282c19:dd:c25:c25d:dd:dd:dd:7bd8
2182c19:dd:c25:c25d:dd:dd:dd:7bd9/1282c19:dd:c25:c25d:dd:dd:dd:7bd9
2192c19:dd:c25:c25d:dd:dd:dd:7bda/1282c19:dd:c25:c25d:dd:dd:dd:7bda
2202c19:dd:c25:c25d:dd:dd:dd:7bdb/1282c19:dd:c25:c25d:dd:dd:dd:7bdb
2212c19:dd:c25:c25d:dd:dd:dd:7bdc/1282c19:dd:c25:c25d:dd:dd:dd:7bdc
2222c19:dd:c25:c25d:dd:dd:dd:7bdd/1282c19:dd:c25:c25d:dd:dd:dd:7bdd
2232c19:dd:c25:c25d:dd:dd:dd:7bde/1282c19:dd:c25:c25d:dd:dd:dd:7bde
2242c19:dd:c25:c25d:dd:dd:dd:7bdf/1282c19:dd:c25:c25d:dd:dd:dd:7bdf
2252c19:dd:c25:c25d:dd:dd:dd:7be0/1282c19:dd:c25:c25d:dd:dd:dd:7be0
2262c19:dd:c25:c25d:dd:dd:dd:7be1/1282c19:dd:c25:c25d:dd:dd:dd:7be1
2272c19:dd:c25:c25d:dd:dd:dd:7be2/1282c19:dd:c25:c25d:dd:dd:dd:7be2
2282c19:dd:c25:c25d:dd:dd:dd:7be3/1282c19:dd:c25:c25d:dd:dd:dd:7be3
2292c19:dd:c25:c25d:dd:dd:dd:7be4/1282c19:dd:c25:c25d:dd:dd:dd:7be4
2302c19:dd:c25:c25d:dd:dd:dd:7be5/1282c19:dd:c25:c25d:dd:dd:dd:7be5
2312c19:dd:c25:c25d:dd:dd:dd:7be6/1282c19:dd:c25:c25d:dd:dd:dd:7be6
2322c19:dd:c25:c25d:dd:dd:dd:7be7/1282c19:dd:c25:c25d:dd:dd:dd:7be7
2332c19:dd:c25:c25d:dd:dd:dd:7be8/1282c19:dd:c25:c25d:dd:dd:dd:7be8
2342c19:dd:c25:c25d:dd:dd:dd:7be9/1282c19:dd:c25:c25d:dd:dd:dd:7be9
2352c19:dd:c25:c25d:dd:dd:dd:7bea/1282c19:dd:c25:c25d:dd:dd:dd:7bea
2362c19:dd:c25:c25d:dd:dd:dd:7beb/1282c19:dd:c25:c25d:dd:dd:dd:7beb
2372c19:dd:c25:c25d:dd:dd:dd:7bec/1282c19:dd:c25:c25d:dd:dd:dd:7bec
2382c19:dd:c25:c25d:dd:dd:dd:7bed/1282c19:dd:c25:c25d:dd:dd:dd:7bed
2392c19:dd:c25:c25d:dd:dd:dd:7bee/1282c19:dd:c25:c25d:dd:dd:dd:7bee
2402c19:dd:c25:c25d:dd:dd:dd:7bef/1282c19:dd:c25:c25d:dd:dd:dd:7bef
2412c19:dd:c25:c25d:dd:dd:dd:7bf0/1282c19:dd:c25:c25d:dd:dd:dd:7bf0
2422c19:dd:c25:c25d:dd:dd:dd:7bf1/1282c19:dd:c25:c25d:dd:dd:dd:7bf1
2432c19:dd:c25:c25d:dd:dd:dd:7bf2/1282c19:dd:c25:c25d:dd:dd:dd:7bf2
2442c19:dd:c25:c25d:dd:dd:dd:7bf3/1282c19:dd:c25:c25d:dd:dd:dd:7bf3
2452c19:dd:c25:c25d:dd:dd:dd:7bf4/1282c19:dd:c25:c25d:dd:dd:dd:7bf4
2462c19:dd:c25:c25d:dd:dd:dd:7bf5/1282c19:dd:c25:c25d:dd:dd:dd:7bf5
2472c19:dd:c25:c25d:dd:dd:dd:7bf6/1282c19:dd:c25:c25d:dd:dd:dd:7bf6
2482c19:dd:c25:c25d:dd:dd:dd:7bf7/1282c19:dd:c25:c25d:dd:dd:dd:7bf7
2492c19:dd:c25:c25d:dd:dd:dd:7bf8/1282c19:dd:c25:c25d:dd:dd:dd:7bf8
2502c19:dd:c25:c25d:dd:dd:dd:7bf9/1282c19:dd:c25:c25d:dd:dd:dd:7bf9
2512c19:dd:c25:c25d:dd:dd:dd:7bfa/1282c19:dd:c25:c25d:dd:dd:dd:7bfa
2522c19:dd:c25:c25d:dd:dd:dd:7bfb/1282c19:dd:c25:c25d:dd:dd:dd:7bfb
2532c19:dd:c25:c25d:dd:dd:dd:7bfc/1282c19:dd:c25:c25d:dd:dd:dd:7bfc
2542c19:dd:c25:c25d:dd:dd:dd:7bfd/1282c19:dd:c25:c25d:dd:dd:dd:7bfd
2552c19:dd:c25:c25d:dd:dd:dd:7bfe/1282c19:dd:c25:c25d:dd:dd:dd:7bfe
2562c19:dd:c25:c25d:dd:dd:dd:7bff/1282c19:dd:c25:c25d:dd:dd:dd:7bff

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.