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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:c25c:a00a:2e00/120
First address
2c19:dd:d9:dd:c25:c25c:a00a:2e00
Last address
2c19:dd:d9:dd:c25:c25c:a00a:2eff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25c:a00a:2e00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.2.a.0.0.a.c.5.2.c.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:c25c:a00a:2e00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25c:a00a:2e00/1282c19:dd:d9:dd:c25:c25c:a00a:2e00
22c19:dd:d9:dd:c25:c25c:a00a:2e01/1282c19:dd:d9:dd:c25:c25c:a00a:2e01
32c19:dd:d9:dd:c25:c25c:a00a:2e02/1282c19:dd:d9:dd:c25:c25c:a00a:2e02
42c19:dd:d9:dd:c25:c25c:a00a:2e03/1282c19:dd:d9:dd:c25:c25c:a00a:2e03
52c19:dd:d9:dd:c25:c25c:a00a:2e04/1282c19:dd:d9:dd:c25:c25c:a00a:2e04
62c19:dd:d9:dd:c25:c25c:a00a:2e05/1282c19:dd:d9:dd:c25:c25c:a00a:2e05
72c19:dd:d9:dd:c25:c25c:a00a:2e06/1282c19:dd:d9:dd:c25:c25c:a00a:2e06
82c19:dd:d9:dd:c25:c25c:a00a:2e07/1282c19:dd:d9:dd:c25:c25c:a00a:2e07
92c19:dd:d9:dd:c25:c25c:a00a:2e08/1282c19:dd:d9:dd:c25:c25c:a00a:2e08
102c19:dd:d9:dd:c25:c25c:a00a:2e09/1282c19:dd:d9:dd:c25:c25c:a00a:2e09
112c19:dd:d9:dd:c25:c25c:a00a:2e0a/1282c19:dd:d9:dd:c25:c25c:a00a:2e0a
122c19:dd:d9:dd:c25:c25c:a00a:2e0b/1282c19:dd:d9:dd:c25:c25c:a00a:2e0b
132c19:dd:d9:dd:c25:c25c:a00a:2e0c/1282c19:dd:d9:dd:c25:c25c:a00a:2e0c
142c19:dd:d9:dd:c25:c25c:a00a:2e0d/1282c19:dd:d9:dd:c25:c25c:a00a:2e0d
152c19:dd:d9:dd:c25:c25c:a00a:2e0e/1282c19:dd:d9:dd:c25:c25c:a00a:2e0e
162c19:dd:d9:dd:c25:c25c:a00a:2e0f/1282c19:dd:d9:dd:c25:c25c:a00a:2e0f
172c19:dd:d9:dd:c25:c25c:a00a:2e10/1282c19:dd:d9:dd:c25:c25c:a00a:2e10
182c19:dd:d9:dd:c25:c25c:a00a:2e11/1282c19:dd:d9:dd:c25:c25c:a00a:2e11
192c19:dd:d9:dd:c25:c25c:a00a:2e12/1282c19:dd:d9:dd:c25:c25c:a00a:2e12
202c19:dd:d9:dd:c25:c25c:a00a:2e13/1282c19:dd:d9:dd:c25:c25c:a00a:2e13
212c19:dd:d9:dd:c25:c25c:a00a:2e14/1282c19:dd:d9:dd:c25:c25c:a00a:2e14
222c19:dd:d9:dd:c25:c25c:a00a:2e15/1282c19:dd:d9:dd:c25:c25c:a00a:2e15
232c19:dd:d9:dd:c25:c25c:a00a:2e16/1282c19:dd:d9:dd:c25:c25c:a00a:2e16
242c19:dd:d9:dd:c25:c25c:a00a:2e17/1282c19:dd:d9:dd:c25:c25c:a00a:2e17
252c19:dd:d9:dd:c25:c25c:a00a:2e18/1282c19:dd:d9:dd:c25:c25c:a00a:2e18
262c19:dd:d9:dd:c25:c25c:a00a:2e19/1282c19:dd:d9:dd:c25:c25c:a00a:2e19
272c19:dd:d9:dd:c25:c25c:a00a:2e1a/1282c19:dd:d9:dd:c25:c25c:a00a:2e1a
282c19:dd:d9:dd:c25:c25c:a00a:2e1b/1282c19:dd:d9:dd:c25:c25c:a00a:2e1b
292c19:dd:d9:dd:c25:c25c:a00a:2e1c/1282c19:dd:d9:dd:c25:c25c:a00a:2e1c
302c19:dd:d9:dd:c25:c25c:a00a:2e1d/1282c19:dd:d9:dd:c25:c25c:a00a:2e1d
312c19:dd:d9:dd:c25:c25c:a00a:2e1e/1282c19:dd:d9:dd:c25:c25c:a00a:2e1e
322c19:dd:d9:dd:c25:c25c:a00a:2e1f/1282c19:dd:d9:dd:c25:c25c:a00a:2e1f
332c19:dd:d9:dd:c25:c25c:a00a:2e20/1282c19:dd:d9:dd:c25:c25c:a00a:2e20
342c19:dd:d9:dd:c25:c25c:a00a:2e21/1282c19:dd:d9:dd:c25:c25c:a00a:2e21
352c19:dd:d9:dd:c25:c25c:a00a:2e22/1282c19:dd:d9:dd:c25:c25c:a00a:2e22
362c19:dd:d9:dd:c25:c25c:a00a:2e23/1282c19:dd:d9:dd:c25:c25c:a00a:2e23
372c19:dd:d9:dd:c25:c25c:a00a:2e24/1282c19:dd:d9:dd:c25:c25c:a00a:2e24
382c19:dd:d9:dd:c25:c25c:a00a:2e25/1282c19:dd:d9:dd:c25:c25c:a00a:2e25
392c19:dd:d9:dd:c25:c25c:a00a:2e26/1282c19:dd:d9:dd:c25:c25c:a00a:2e26
402c19:dd:d9:dd:c25:c25c:a00a:2e27/1282c19:dd:d9:dd:c25:c25c:a00a:2e27
412c19:dd:d9:dd:c25:c25c:a00a:2e28/1282c19:dd:d9:dd:c25:c25c:a00a:2e28
422c19:dd:d9:dd:c25:c25c:a00a:2e29/1282c19:dd:d9:dd:c25:c25c:a00a:2e29
432c19:dd:d9:dd:c25:c25c:a00a:2e2a/1282c19:dd:d9:dd:c25:c25c:a00a:2e2a
442c19:dd:d9:dd:c25:c25c:a00a:2e2b/1282c19:dd:d9:dd:c25:c25c:a00a:2e2b
452c19:dd:d9:dd:c25:c25c:a00a:2e2c/1282c19:dd:d9:dd:c25:c25c:a00a:2e2c
462c19:dd:d9:dd:c25:c25c:a00a:2e2d/1282c19:dd:d9:dd:c25:c25c:a00a:2e2d
472c19:dd:d9:dd:c25:c25c:a00a:2e2e/1282c19:dd:d9:dd:c25:c25c:a00a:2e2e
482c19:dd:d9:dd:c25:c25c:a00a:2e2f/1282c19:dd:d9:dd:c25:c25c:a00a:2e2f
492c19:dd:d9:dd:c25:c25c:a00a:2e30/1282c19:dd:d9:dd:c25:c25c:a00a:2e30
502c19:dd:d9:dd:c25:c25c:a00a:2e31/1282c19:dd:d9:dd:c25:c25c:a00a:2e31
512c19:dd:d9:dd:c25:c25c:a00a:2e32/1282c19:dd:d9:dd:c25:c25c:a00a:2e32
522c19:dd:d9:dd:c25:c25c:a00a:2e33/1282c19:dd:d9:dd:c25:c25c:a00a:2e33
532c19:dd:d9:dd:c25:c25c:a00a:2e34/1282c19:dd:d9:dd:c25:c25c:a00a:2e34
542c19:dd:d9:dd:c25:c25c:a00a:2e35/1282c19:dd:d9:dd:c25:c25c:a00a:2e35
552c19:dd:d9:dd:c25:c25c:a00a:2e36/1282c19:dd:d9:dd:c25:c25c:a00a:2e36
562c19:dd:d9:dd:c25:c25c:a00a:2e37/1282c19:dd:d9:dd:c25:c25c:a00a:2e37
572c19:dd:d9:dd:c25:c25c:a00a:2e38/1282c19:dd:d9:dd:c25:c25c:a00a:2e38
582c19:dd:d9:dd:c25:c25c:a00a:2e39/1282c19:dd:d9:dd:c25:c25c:a00a:2e39
592c19:dd:d9:dd:c25:c25c:a00a:2e3a/1282c19:dd:d9:dd:c25:c25c:a00a:2e3a
602c19:dd:d9:dd:c25:c25c:a00a:2e3b/1282c19:dd:d9:dd:c25:c25c:a00a:2e3b
612c19:dd:d9:dd:c25:c25c:a00a:2e3c/1282c19:dd:d9:dd:c25:c25c:a00a:2e3c
622c19:dd:d9:dd:c25:c25c:a00a:2e3d/1282c19:dd:d9:dd:c25:c25c:a00a:2e3d
632c19:dd:d9:dd:c25:c25c:a00a:2e3e/1282c19:dd:d9:dd:c25:c25c:a00a:2e3e
642c19:dd:d9:dd:c25:c25c:a00a:2e3f/1282c19:dd:d9:dd:c25:c25c:a00a:2e3f
652c19:dd:d9:dd:c25:c25c:a00a:2e40/1282c19:dd:d9:dd:c25:c25c:a00a:2e40
662c19:dd:d9:dd:c25:c25c:a00a:2e41/1282c19:dd:d9:dd:c25:c25c:a00a:2e41
672c19:dd:d9:dd:c25:c25c:a00a:2e42/1282c19:dd:d9:dd:c25:c25c:a00a:2e42
682c19:dd:d9:dd:c25:c25c:a00a:2e43/1282c19:dd:d9:dd:c25:c25c:a00a:2e43
692c19:dd:d9:dd:c25:c25c:a00a:2e44/1282c19:dd:d9:dd:c25:c25c:a00a:2e44
702c19:dd:d9:dd:c25:c25c:a00a:2e45/1282c19:dd:d9:dd:c25:c25c:a00a:2e45
712c19:dd:d9:dd:c25:c25c:a00a:2e46/1282c19:dd:d9:dd:c25:c25c:a00a:2e46
722c19:dd:d9:dd:c25:c25c:a00a:2e47/1282c19:dd:d9:dd:c25:c25c:a00a:2e47
732c19:dd:d9:dd:c25:c25c:a00a:2e48/1282c19:dd:d9:dd:c25:c25c:a00a:2e48
742c19:dd:d9:dd:c25:c25c:a00a:2e49/1282c19:dd:d9:dd:c25:c25c:a00a:2e49
752c19:dd:d9:dd:c25:c25c:a00a:2e4a/1282c19:dd:d9:dd:c25:c25c:a00a:2e4a
762c19:dd:d9:dd:c25:c25c:a00a:2e4b/1282c19:dd:d9:dd:c25:c25c:a00a:2e4b
772c19:dd:d9:dd:c25:c25c:a00a:2e4c/1282c19:dd:d9:dd:c25:c25c:a00a:2e4c
782c19:dd:d9:dd:c25:c25c:a00a:2e4d/1282c19:dd:d9:dd:c25:c25c:a00a:2e4d
792c19:dd:d9:dd:c25:c25c:a00a:2e4e/1282c19:dd:d9:dd:c25:c25c:a00a:2e4e
802c19:dd:d9:dd:c25:c25c:a00a:2e4f/1282c19:dd:d9:dd:c25:c25c:a00a:2e4f
812c19:dd:d9:dd:c25:c25c:a00a:2e50/1282c19:dd:d9:dd:c25:c25c:a00a:2e50
822c19:dd:d9:dd:c25:c25c:a00a:2e51/1282c19:dd:d9:dd:c25:c25c:a00a:2e51
832c19:dd:d9:dd:c25:c25c:a00a:2e52/1282c19:dd:d9:dd:c25:c25c:a00a:2e52
842c19:dd:d9:dd:c25:c25c:a00a:2e53/1282c19:dd:d9:dd:c25:c25c:a00a:2e53
852c19:dd:d9:dd:c25:c25c:a00a:2e54/1282c19:dd:d9:dd:c25:c25c:a00a:2e54
862c19:dd:d9:dd:c25:c25c:a00a:2e55/1282c19:dd:d9:dd:c25:c25c:a00a:2e55
872c19:dd:d9:dd:c25:c25c:a00a:2e56/1282c19:dd:d9:dd:c25:c25c:a00a:2e56
882c19:dd:d9:dd:c25:c25c:a00a:2e57/1282c19:dd:d9:dd:c25:c25c:a00a:2e57
892c19:dd:d9:dd:c25:c25c:a00a:2e58/1282c19:dd:d9:dd:c25:c25c:a00a:2e58
902c19:dd:d9:dd:c25:c25c:a00a:2e59/1282c19:dd:d9:dd:c25:c25c:a00a:2e59
912c19:dd:d9:dd:c25:c25c:a00a:2e5a/1282c19:dd:d9:dd:c25:c25c:a00a:2e5a
922c19:dd:d9:dd:c25:c25c:a00a:2e5b/1282c19:dd:d9:dd:c25:c25c:a00a:2e5b
932c19:dd:d9:dd:c25:c25c:a00a:2e5c/1282c19:dd:d9:dd:c25:c25c:a00a:2e5c
942c19:dd:d9:dd:c25:c25c:a00a:2e5d/1282c19:dd:d9:dd:c25:c25c:a00a:2e5d
952c19:dd:d9:dd:c25:c25c:a00a:2e5e/1282c19:dd:d9:dd:c25:c25c:a00a:2e5e
962c19:dd:d9:dd:c25:c25c:a00a:2e5f/1282c19:dd:d9:dd:c25:c25c:a00a:2e5f
972c19:dd:d9:dd:c25:c25c:a00a:2e60/1282c19:dd:d9:dd:c25:c25c:a00a:2e60
982c19:dd:d9:dd:c25:c25c:a00a:2e61/1282c19:dd:d9:dd:c25:c25c:a00a:2e61
992c19:dd:d9:dd:c25:c25c:a00a:2e62/1282c19:dd:d9:dd:c25:c25c:a00a:2e62
1002c19:dd:d9:dd:c25:c25c:a00a:2e63/1282c19:dd:d9:dd:c25:c25c:a00a:2e63
1012c19:dd:d9:dd:c25:c25c:a00a:2e64/1282c19:dd:d9:dd:c25:c25c:a00a:2e64
1022c19:dd:d9:dd:c25:c25c:a00a:2e65/1282c19:dd:d9:dd:c25:c25c:a00a:2e65
1032c19:dd:d9:dd:c25:c25c:a00a:2e66/1282c19:dd:d9:dd:c25:c25c:a00a:2e66
1042c19:dd:d9:dd:c25:c25c:a00a:2e67/1282c19:dd:d9:dd:c25:c25c:a00a:2e67
1052c19:dd:d9:dd:c25:c25c:a00a:2e68/1282c19:dd:d9:dd:c25:c25c:a00a:2e68
1062c19:dd:d9:dd:c25:c25c:a00a:2e69/1282c19:dd:d9:dd:c25:c25c:a00a:2e69
1072c19:dd:d9:dd:c25:c25c:a00a:2e6a/1282c19:dd:d9:dd:c25:c25c:a00a:2e6a
1082c19:dd:d9:dd:c25:c25c:a00a:2e6b/1282c19:dd:d9:dd:c25:c25c:a00a:2e6b
1092c19:dd:d9:dd:c25:c25c:a00a:2e6c/1282c19:dd:d9:dd:c25:c25c:a00a:2e6c
1102c19:dd:d9:dd:c25:c25c:a00a:2e6d/1282c19:dd:d9:dd:c25:c25c:a00a:2e6d
1112c19:dd:d9:dd:c25:c25c:a00a:2e6e/1282c19:dd:d9:dd:c25:c25c:a00a:2e6e
1122c19:dd:d9:dd:c25:c25c:a00a:2e6f/1282c19:dd:d9:dd:c25:c25c:a00a:2e6f
1132c19:dd:d9:dd:c25:c25c:a00a:2e70/1282c19:dd:d9:dd:c25:c25c:a00a:2e70
1142c19:dd:d9:dd:c25:c25c:a00a:2e71/1282c19:dd:d9:dd:c25:c25c:a00a:2e71
1152c19:dd:d9:dd:c25:c25c:a00a:2e72/1282c19:dd:d9:dd:c25:c25c:a00a:2e72
1162c19:dd:d9:dd:c25:c25c:a00a:2e73/1282c19:dd:d9:dd:c25:c25c:a00a:2e73
1172c19:dd:d9:dd:c25:c25c:a00a:2e74/1282c19:dd:d9:dd:c25:c25c:a00a:2e74
1182c19:dd:d9:dd:c25:c25c:a00a:2e75/1282c19:dd:d9:dd:c25:c25c:a00a:2e75
1192c19:dd:d9:dd:c25:c25c:a00a:2e76/1282c19:dd:d9:dd:c25:c25c:a00a:2e76
1202c19:dd:d9:dd:c25:c25c:a00a:2e77/1282c19:dd:d9:dd:c25:c25c:a00a:2e77
1212c19:dd:d9:dd:c25:c25c:a00a:2e78/1282c19:dd:d9:dd:c25:c25c:a00a:2e78
1222c19:dd:d9:dd:c25:c25c:a00a:2e79/1282c19:dd:d9:dd:c25:c25c:a00a:2e79
1232c19:dd:d9:dd:c25:c25c:a00a:2e7a/1282c19:dd:d9:dd:c25:c25c:a00a:2e7a
1242c19:dd:d9:dd:c25:c25c:a00a:2e7b/1282c19:dd:d9:dd:c25:c25c:a00a:2e7b
1252c19:dd:d9:dd:c25:c25c:a00a:2e7c/1282c19:dd:d9:dd:c25:c25c:a00a:2e7c
1262c19:dd:d9:dd:c25:c25c:a00a:2e7d/1282c19:dd:d9:dd:c25:c25c:a00a:2e7d
1272c19:dd:d9:dd:c25:c25c:a00a:2e7e/1282c19:dd:d9:dd:c25:c25c:a00a:2e7e
1282c19:dd:d9:dd:c25:c25c:a00a:2e7f/1282c19:dd:d9:dd:c25:c25c:a00a:2e7f
1292c19:dd:d9:dd:c25:c25c:a00a:2e80/1282c19:dd:d9:dd:c25:c25c:a00a:2e80
1302c19:dd:d9:dd:c25:c25c:a00a:2e81/1282c19:dd:d9:dd:c25:c25c:a00a:2e81
1312c19:dd:d9:dd:c25:c25c:a00a:2e82/1282c19:dd:d9:dd:c25:c25c:a00a:2e82
1322c19:dd:d9:dd:c25:c25c:a00a:2e83/1282c19:dd:d9:dd:c25:c25c:a00a:2e83
1332c19:dd:d9:dd:c25:c25c:a00a:2e84/1282c19:dd:d9:dd:c25:c25c:a00a:2e84
1342c19:dd:d9:dd:c25:c25c:a00a:2e85/1282c19:dd:d9:dd:c25:c25c:a00a:2e85
1352c19:dd:d9:dd:c25:c25c:a00a:2e86/1282c19:dd:d9:dd:c25:c25c:a00a:2e86
1362c19:dd:d9:dd:c25:c25c:a00a:2e87/1282c19:dd:d9:dd:c25:c25c:a00a:2e87
1372c19:dd:d9:dd:c25:c25c:a00a:2e88/1282c19:dd:d9:dd:c25:c25c:a00a:2e88
1382c19:dd:d9:dd:c25:c25c:a00a:2e89/1282c19:dd:d9:dd:c25:c25c:a00a:2e89
1392c19:dd:d9:dd:c25:c25c:a00a:2e8a/1282c19:dd:d9:dd:c25:c25c:a00a:2e8a
1402c19:dd:d9:dd:c25:c25c:a00a:2e8b/1282c19:dd:d9:dd:c25:c25c:a00a:2e8b
1412c19:dd:d9:dd:c25:c25c:a00a:2e8c/1282c19:dd:d9:dd:c25:c25c:a00a:2e8c
1422c19:dd:d9:dd:c25:c25c:a00a:2e8d/1282c19:dd:d9:dd:c25:c25c:a00a:2e8d
1432c19:dd:d9:dd:c25:c25c:a00a:2e8e/1282c19:dd:d9:dd:c25:c25c:a00a:2e8e
1442c19:dd:d9:dd:c25:c25c:a00a:2e8f/1282c19:dd:d9:dd:c25:c25c:a00a:2e8f
1452c19:dd:d9:dd:c25:c25c:a00a:2e90/1282c19:dd:d9:dd:c25:c25c:a00a:2e90
1462c19:dd:d9:dd:c25:c25c:a00a:2e91/1282c19:dd:d9:dd:c25:c25c:a00a:2e91
1472c19:dd:d9:dd:c25:c25c:a00a:2e92/1282c19:dd:d9:dd:c25:c25c:a00a:2e92
1482c19:dd:d9:dd:c25:c25c:a00a:2e93/1282c19:dd:d9:dd:c25:c25c:a00a:2e93
1492c19:dd:d9:dd:c25:c25c:a00a:2e94/1282c19:dd:d9:dd:c25:c25c:a00a:2e94
1502c19:dd:d9:dd:c25:c25c:a00a:2e95/1282c19:dd:d9:dd:c25:c25c:a00a:2e95
1512c19:dd:d9:dd:c25:c25c:a00a:2e96/1282c19:dd:d9:dd:c25:c25c:a00a:2e96
1522c19:dd:d9:dd:c25:c25c:a00a:2e97/1282c19:dd:d9:dd:c25:c25c:a00a:2e97
1532c19:dd:d9:dd:c25:c25c:a00a:2e98/1282c19:dd:d9:dd:c25:c25c:a00a:2e98
1542c19:dd:d9:dd:c25:c25c:a00a:2e99/1282c19:dd:d9:dd:c25:c25c:a00a:2e99
1552c19:dd:d9:dd:c25:c25c:a00a:2e9a/1282c19:dd:d9:dd:c25:c25c:a00a:2e9a
1562c19:dd:d9:dd:c25:c25c:a00a:2e9b/1282c19:dd:d9:dd:c25:c25c:a00a:2e9b
1572c19:dd:d9:dd:c25:c25c:a00a:2e9c/1282c19:dd:d9:dd:c25:c25c:a00a:2e9c
1582c19:dd:d9:dd:c25:c25c:a00a:2e9d/1282c19:dd:d9:dd:c25:c25c:a00a:2e9d
1592c19:dd:d9:dd:c25:c25c:a00a:2e9e/1282c19:dd:d9:dd:c25:c25c:a00a:2e9e
1602c19:dd:d9:dd:c25:c25c:a00a:2e9f/1282c19:dd:d9:dd:c25:c25c:a00a:2e9f
1612c19:dd:d9:dd:c25:c25c:a00a:2ea0/1282c19:dd:d9:dd:c25:c25c:a00a:2ea0
1622c19:dd:d9:dd:c25:c25c:a00a:2ea1/1282c19:dd:d9:dd:c25:c25c:a00a:2ea1
1632c19:dd:d9:dd:c25:c25c:a00a:2ea2/1282c19:dd:d9:dd:c25:c25c:a00a:2ea2
1642c19:dd:d9:dd:c25:c25c:a00a:2ea3/1282c19:dd:d9:dd:c25:c25c:a00a:2ea3
1652c19:dd:d9:dd:c25:c25c:a00a:2ea4/1282c19:dd:d9:dd:c25:c25c:a00a:2ea4
1662c19:dd:d9:dd:c25:c25c:a00a:2ea5/1282c19:dd:d9:dd:c25:c25c:a00a:2ea5
1672c19:dd:d9:dd:c25:c25c:a00a:2ea6/1282c19:dd:d9:dd:c25:c25c:a00a:2ea6
1682c19:dd:d9:dd:c25:c25c:a00a:2ea7/1282c19:dd:d9:dd:c25:c25c:a00a:2ea7
1692c19:dd:d9:dd:c25:c25c:a00a:2ea8/1282c19:dd:d9:dd:c25:c25c:a00a:2ea8
1702c19:dd:d9:dd:c25:c25c:a00a:2ea9/1282c19:dd:d9:dd:c25:c25c:a00a:2ea9
1712c19:dd:d9:dd:c25:c25c:a00a:2eaa/1282c19:dd:d9:dd:c25:c25c:a00a:2eaa
1722c19:dd:d9:dd:c25:c25c:a00a:2eab/1282c19:dd:d9:dd:c25:c25c:a00a:2eab
1732c19:dd:d9:dd:c25:c25c:a00a:2eac/1282c19:dd:d9:dd:c25:c25c:a00a:2eac
1742c19:dd:d9:dd:c25:c25c:a00a:2ead/1282c19:dd:d9:dd:c25:c25c:a00a:2ead
1752c19:dd:d9:dd:c25:c25c:a00a:2eae/1282c19:dd:d9:dd:c25:c25c:a00a:2eae
1762c19:dd:d9:dd:c25:c25c:a00a:2eaf/1282c19:dd:d9:dd:c25:c25c:a00a:2eaf
1772c19:dd:d9:dd:c25:c25c:a00a:2eb0/1282c19:dd:d9:dd:c25:c25c:a00a:2eb0
1782c19:dd:d9:dd:c25:c25c:a00a:2eb1/1282c19:dd:d9:dd:c25:c25c:a00a:2eb1
1792c19:dd:d9:dd:c25:c25c:a00a:2eb2/1282c19:dd:d9:dd:c25:c25c:a00a:2eb2
1802c19:dd:d9:dd:c25:c25c:a00a:2eb3/1282c19:dd:d9:dd:c25:c25c:a00a:2eb3
1812c19:dd:d9:dd:c25:c25c:a00a:2eb4/1282c19:dd:d9:dd:c25:c25c:a00a:2eb4
1822c19:dd:d9:dd:c25:c25c:a00a:2eb5/1282c19:dd:d9:dd:c25:c25c:a00a:2eb5
1832c19:dd:d9:dd:c25:c25c:a00a:2eb6/1282c19:dd:d9:dd:c25:c25c:a00a:2eb6
1842c19:dd:d9:dd:c25:c25c:a00a:2eb7/1282c19:dd:d9:dd:c25:c25c:a00a:2eb7
1852c19:dd:d9:dd:c25:c25c:a00a:2eb8/1282c19:dd:d9:dd:c25:c25c:a00a:2eb8
1862c19:dd:d9:dd:c25:c25c:a00a:2eb9/1282c19:dd:d9:dd:c25:c25c:a00a:2eb9
1872c19:dd:d9:dd:c25:c25c:a00a:2eba/1282c19:dd:d9:dd:c25:c25c:a00a:2eba
1882c19:dd:d9:dd:c25:c25c:a00a:2ebb/1282c19:dd:d9:dd:c25:c25c:a00a:2ebb
1892c19:dd:d9:dd:c25:c25c:a00a:2ebc/1282c19:dd:d9:dd:c25:c25c:a00a:2ebc
1902c19:dd:d9:dd:c25:c25c:a00a:2ebd/1282c19:dd:d9:dd:c25:c25c:a00a:2ebd
1912c19:dd:d9:dd:c25:c25c:a00a:2ebe/1282c19:dd:d9:dd:c25:c25c:a00a:2ebe
1922c19:dd:d9:dd:c25:c25c:a00a:2ebf/1282c19:dd:d9:dd:c25:c25c:a00a:2ebf
1932c19:dd:d9:dd:c25:c25c:a00a:2ec0/1282c19:dd:d9:dd:c25:c25c:a00a:2ec0
1942c19:dd:d9:dd:c25:c25c:a00a:2ec1/1282c19:dd:d9:dd:c25:c25c:a00a:2ec1
1952c19:dd:d9:dd:c25:c25c:a00a:2ec2/1282c19:dd:d9:dd:c25:c25c:a00a:2ec2
1962c19:dd:d9:dd:c25:c25c:a00a:2ec3/1282c19:dd:d9:dd:c25:c25c:a00a:2ec3
1972c19:dd:d9:dd:c25:c25c:a00a:2ec4/1282c19:dd:d9:dd:c25:c25c:a00a:2ec4
1982c19:dd:d9:dd:c25:c25c:a00a:2ec5/1282c19:dd:d9:dd:c25:c25c:a00a:2ec5
1992c19:dd:d9:dd:c25:c25c:a00a:2ec6/1282c19:dd:d9:dd:c25:c25c:a00a:2ec6
2002c19:dd:d9:dd:c25:c25c:a00a:2ec7/1282c19:dd:d9:dd:c25:c25c:a00a:2ec7
2012c19:dd:d9:dd:c25:c25c:a00a:2ec8/1282c19:dd:d9:dd:c25:c25c:a00a:2ec8
2022c19:dd:d9:dd:c25:c25c:a00a:2ec9/1282c19:dd:d9:dd:c25:c25c:a00a:2ec9
2032c19:dd:d9:dd:c25:c25c:a00a:2eca/1282c19:dd:d9:dd:c25:c25c:a00a:2eca
2042c19:dd:d9:dd:c25:c25c:a00a:2ecb/1282c19:dd:d9:dd:c25:c25c:a00a:2ecb
2052c19:dd:d9:dd:c25:c25c:a00a:2ecc/1282c19:dd:d9:dd:c25:c25c:a00a:2ecc
2062c19:dd:d9:dd:c25:c25c:a00a:2ecd/1282c19:dd:d9:dd:c25:c25c:a00a:2ecd
2072c19:dd:d9:dd:c25:c25c:a00a:2ece/1282c19:dd:d9:dd:c25:c25c:a00a:2ece
2082c19:dd:d9:dd:c25:c25c:a00a:2ecf/1282c19:dd:d9:dd:c25:c25c:a00a:2ecf
2092c19:dd:d9:dd:c25:c25c:a00a:2ed0/1282c19:dd:d9:dd:c25:c25c:a00a:2ed0
2102c19:dd:d9:dd:c25:c25c:a00a:2ed1/1282c19:dd:d9:dd:c25:c25c:a00a:2ed1
2112c19:dd:d9:dd:c25:c25c:a00a:2ed2/1282c19:dd:d9:dd:c25:c25c:a00a:2ed2
2122c19:dd:d9:dd:c25:c25c:a00a:2ed3/1282c19:dd:d9:dd:c25:c25c:a00a:2ed3
2132c19:dd:d9:dd:c25:c25c:a00a:2ed4/1282c19:dd:d9:dd:c25:c25c:a00a:2ed4
2142c19:dd:d9:dd:c25:c25c:a00a:2ed5/1282c19:dd:d9:dd:c25:c25c:a00a:2ed5
2152c19:dd:d9:dd:c25:c25c:a00a:2ed6/1282c19:dd:d9:dd:c25:c25c:a00a:2ed6
2162c19:dd:d9:dd:c25:c25c:a00a:2ed7/1282c19:dd:d9:dd:c25:c25c:a00a:2ed7
2172c19:dd:d9:dd:c25:c25c:a00a:2ed8/1282c19:dd:d9:dd:c25:c25c:a00a:2ed8
2182c19:dd:d9:dd:c25:c25c:a00a:2ed9/1282c19:dd:d9:dd:c25:c25c:a00a:2ed9
2192c19:dd:d9:dd:c25:c25c:a00a:2eda/1282c19:dd:d9:dd:c25:c25c:a00a:2eda
2202c19:dd:d9:dd:c25:c25c:a00a:2edb/1282c19:dd:d9:dd:c25:c25c:a00a:2edb
2212c19:dd:d9:dd:c25:c25c:a00a:2edc/1282c19:dd:d9:dd:c25:c25c:a00a:2edc
2222c19:dd:d9:dd:c25:c25c:a00a:2edd/1282c19:dd:d9:dd:c25:c25c:a00a:2edd
2232c19:dd:d9:dd:c25:c25c:a00a:2ede/1282c19:dd:d9:dd:c25:c25c:a00a:2ede
2242c19:dd:d9:dd:c25:c25c:a00a:2edf/1282c19:dd:d9:dd:c25:c25c:a00a:2edf
2252c19:dd:d9:dd:c25:c25c:a00a:2ee0/1282c19:dd:d9:dd:c25:c25c:a00a:2ee0
2262c19:dd:d9:dd:c25:c25c:a00a:2ee1/1282c19:dd:d9:dd:c25:c25c:a00a:2ee1
2272c19:dd:d9:dd:c25:c25c:a00a:2ee2/1282c19:dd:d9:dd:c25:c25c:a00a:2ee2
2282c19:dd:d9:dd:c25:c25c:a00a:2ee3/1282c19:dd:d9:dd:c25:c25c:a00a:2ee3
2292c19:dd:d9:dd:c25:c25c:a00a:2ee4/1282c19:dd:d9:dd:c25:c25c:a00a:2ee4
2302c19:dd:d9:dd:c25:c25c:a00a:2ee5/1282c19:dd:d9:dd:c25:c25c:a00a:2ee5
2312c19:dd:d9:dd:c25:c25c:a00a:2ee6/1282c19:dd:d9:dd:c25:c25c:a00a:2ee6
2322c19:dd:d9:dd:c25:c25c:a00a:2ee7/1282c19:dd:d9:dd:c25:c25c:a00a:2ee7
2332c19:dd:d9:dd:c25:c25c:a00a:2ee8/1282c19:dd:d9:dd:c25:c25c:a00a:2ee8
2342c19:dd:d9:dd:c25:c25c:a00a:2ee9/1282c19:dd:d9:dd:c25:c25c:a00a:2ee9
2352c19:dd:d9:dd:c25:c25c:a00a:2eea/1282c19:dd:d9:dd:c25:c25c:a00a:2eea
2362c19:dd:d9:dd:c25:c25c:a00a:2eeb/1282c19:dd:d9:dd:c25:c25c:a00a:2eeb
2372c19:dd:d9:dd:c25:c25c:a00a:2eec/1282c19:dd:d9:dd:c25:c25c:a00a:2eec
2382c19:dd:d9:dd:c25:c25c:a00a:2eed/1282c19:dd:d9:dd:c25:c25c:a00a:2eed
2392c19:dd:d9:dd:c25:c25c:a00a:2eee/1282c19:dd:d9:dd:c25:c25c:a00a:2eee
2402c19:dd:d9:dd:c25:c25c:a00a:2eef/1282c19:dd:d9:dd:c25:c25c:a00a:2eef
2412c19:dd:d9:dd:c25:c25c:a00a:2ef0/1282c19:dd:d9:dd:c25:c25c:a00a:2ef0
2422c19:dd:d9:dd:c25:c25c:a00a:2ef1/1282c19:dd:d9:dd:c25:c25c:a00a:2ef1
2432c19:dd:d9:dd:c25:c25c:a00a:2ef2/1282c19:dd:d9:dd:c25:c25c:a00a:2ef2
2442c19:dd:d9:dd:c25:c25c:a00a:2ef3/1282c19:dd:d9:dd:c25:c25c:a00a:2ef3
2452c19:dd:d9:dd:c25:c25c:a00a:2ef4/1282c19:dd:d9:dd:c25:c25c:a00a:2ef4
2462c19:dd:d9:dd:c25:c25c:a00a:2ef5/1282c19:dd:d9:dd:c25:c25c:a00a:2ef5
2472c19:dd:d9:dd:c25:c25c:a00a:2ef6/1282c19:dd:d9:dd:c25:c25c:a00a:2ef6
2482c19:dd:d9:dd:c25:c25c:a00a:2ef7/1282c19:dd:d9:dd:c25:c25c:a00a:2ef7
2492c19:dd:d9:dd:c25:c25c:a00a:2ef8/1282c19:dd:d9:dd:c25:c25c:a00a:2ef8
2502c19:dd:d9:dd:c25:c25c:a00a:2ef9/1282c19:dd:d9:dd:c25:c25c:a00a:2ef9
2512c19:dd:d9:dd:c25:c25c:a00a:2efa/1282c19:dd:d9:dd:c25:c25c:a00a:2efa
2522c19:dd:d9:dd:c25:c25c:a00a:2efb/1282c19:dd:d9:dd:c25:c25c:a00a:2efb
2532c19:dd:d9:dd:c25:c25c:a00a:2efc/1282c19:dd:d9:dd:c25:c25c:a00a:2efc
2542c19:dd:d9:dd:c25:c25c:a00a:2efd/1282c19:dd:d9:dd:c25:c25c:a00a:2efd
2552c19:dd:d9:dd:c25:c25c:a00a:2efe/1282c19:dd:d9:dd:c25:c25c:a00a:2efe
2562c19:dd:d9:dd:c25:c25c:a00a:2eff/1282c19:dd:d9:dd:c25:c25c:a00a:2eff

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.