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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:ec00:c25:c25e:dd:ddea:e00/119
First address
2c19:dd:ec00:c25:c25e:dd:ddea:e00
Last address
2c19:dd:ec00:c25:c25e:dd:ddea:fff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:ec00:0c25:c25e:00dd:ddea:0e00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
e.0.a.e.d.d.d.d.0.0.e.5.2.c.5.2.c.0.0.0.c.e.d.d.0.0.9.1.c.2.ip6.arpa
f.0.a.e.d.d.d.d.0.0.e.5.2.c.5.2.c.0.0.0.c.e.d.d.0.0.9.1.c.2.ip6.arpa
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/128
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:ec00:c25:c25e:dd:ddea:e00/119 makes 512 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:ec00:c25:c25e:dd:ddea:e00/1282c19:dd:ec00:c25:c25e:dd:ddea:e00
22c19:dd:ec00:c25:c25e:dd:ddea:e01/1282c19:dd:ec00:c25:c25e:dd:ddea:e01
32c19:dd:ec00:c25:c25e:dd:ddea:e02/1282c19:dd:ec00:c25:c25e:dd:ddea:e02
42c19:dd:ec00:c25:c25e:dd:ddea:e03/1282c19:dd:ec00:c25:c25e:dd:ddea:e03
52c19:dd:ec00:c25:c25e:dd:ddea:e04/1282c19:dd:ec00:c25:c25e:dd:ddea:e04
62c19:dd:ec00:c25:c25e:dd:ddea:e05/1282c19:dd:ec00:c25:c25e:dd:ddea:e05
72c19:dd:ec00:c25:c25e:dd:ddea:e06/1282c19:dd:ec00:c25:c25e:dd:ddea:e06
82c19:dd:ec00:c25:c25e:dd:ddea:e07/1282c19:dd:ec00:c25:c25e:dd:ddea:e07
92c19:dd:ec00:c25:c25e:dd:ddea:e08/1282c19:dd:ec00:c25:c25e:dd:ddea:e08
102c19:dd:ec00:c25:c25e:dd:ddea:e09/1282c19:dd:ec00:c25:c25e:dd:ddea:e09
112c19:dd:ec00:c25:c25e:dd:ddea:e0a/1282c19:dd:ec00:c25:c25e:dd:ddea:e0a
122c19:dd:ec00:c25:c25e:dd:ddea:e0b/1282c19:dd:ec00:c25:c25e:dd:ddea:e0b
132c19:dd:ec00:c25:c25e:dd:ddea:e0c/1282c19:dd:ec00:c25:c25e:dd:ddea:e0c
142c19:dd:ec00:c25:c25e:dd:ddea:e0d/1282c19:dd:ec00:c25:c25e:dd:ddea:e0d
152c19:dd:ec00:c25:c25e:dd:ddea:e0e/1282c19:dd:ec00:c25:c25e:dd:ddea:e0e
162c19:dd:ec00:c25:c25e:dd:ddea:e0f/1282c19:dd:ec00:c25:c25e:dd:ddea:e0f
172c19:dd:ec00:c25:c25e:dd:ddea:e10/1282c19:dd:ec00:c25:c25e:dd:ddea:e10
182c19:dd:ec00:c25:c25e:dd:ddea:e11/1282c19:dd:ec00:c25:c25e:dd:ddea:e11
192c19:dd:ec00:c25:c25e:dd:ddea:e12/1282c19:dd:ec00:c25:c25e:dd:ddea:e12
202c19:dd:ec00:c25:c25e:dd:ddea:e13/1282c19:dd:ec00:c25:c25e:dd:ddea:e13
212c19:dd:ec00:c25:c25e:dd:ddea:e14/1282c19:dd:ec00:c25:c25e:dd:ddea:e14
222c19:dd:ec00:c25:c25e:dd:ddea:e15/1282c19:dd:ec00:c25:c25e:dd:ddea:e15
232c19:dd:ec00:c25:c25e:dd:ddea:e16/1282c19:dd:ec00:c25:c25e:dd:ddea:e16
242c19:dd:ec00:c25:c25e:dd:ddea:e17/1282c19:dd:ec00:c25:c25e:dd:ddea:e17
252c19:dd:ec00:c25:c25e:dd:ddea:e18/1282c19:dd:ec00:c25:c25e:dd:ddea:e18
262c19:dd:ec00:c25:c25e:dd:ddea:e19/1282c19:dd:ec00:c25:c25e:dd:ddea:e19
272c19:dd:ec00:c25:c25e:dd:ddea:e1a/1282c19:dd:ec00:c25:c25e:dd:ddea:e1a
282c19:dd:ec00:c25:c25e:dd:ddea:e1b/1282c19:dd:ec00:c25:c25e:dd:ddea:e1b
292c19:dd:ec00:c25:c25e:dd:ddea:e1c/1282c19:dd:ec00:c25:c25e:dd:ddea:e1c
302c19:dd:ec00:c25:c25e:dd:ddea:e1d/1282c19:dd:ec00:c25:c25e:dd:ddea:e1d
312c19:dd:ec00:c25:c25e:dd:ddea:e1e/1282c19:dd:ec00:c25:c25e:dd:ddea:e1e
322c19:dd:ec00:c25:c25e:dd:ddea:e1f/1282c19:dd:ec00:c25:c25e:dd:ddea:e1f
332c19:dd:ec00:c25:c25e:dd:ddea:e20/1282c19:dd:ec00:c25:c25e:dd:ddea:e20
342c19:dd:ec00:c25:c25e:dd:ddea:e21/1282c19:dd:ec00:c25:c25e:dd:ddea:e21
352c19:dd:ec00:c25:c25e:dd:ddea:e22/1282c19:dd:ec00:c25:c25e:dd:ddea:e22
362c19:dd:ec00:c25:c25e:dd:ddea:e23/1282c19:dd:ec00:c25:c25e:dd:ddea:e23
372c19:dd:ec00:c25:c25e:dd:ddea:e24/1282c19:dd:ec00:c25:c25e:dd:ddea:e24
382c19:dd:ec00:c25:c25e:dd:ddea:e25/1282c19:dd:ec00:c25:c25e:dd:ddea:e25
392c19:dd:ec00:c25:c25e:dd:ddea:e26/1282c19:dd:ec00:c25:c25e:dd:ddea:e26
402c19:dd:ec00:c25:c25e:dd:ddea:e27/1282c19:dd:ec00:c25:c25e:dd:ddea:e27
412c19:dd:ec00:c25:c25e:dd:ddea:e28/1282c19:dd:ec00:c25:c25e:dd:ddea:e28
422c19:dd:ec00:c25:c25e:dd:ddea:e29/1282c19:dd:ec00:c25:c25e:dd:ddea:e29
432c19:dd:ec00:c25:c25e:dd:ddea:e2a/1282c19:dd:ec00:c25:c25e:dd:ddea:e2a
442c19:dd:ec00:c25:c25e:dd:ddea:e2b/1282c19:dd:ec00:c25:c25e:dd:ddea:e2b
452c19:dd:ec00:c25:c25e:dd:ddea:e2c/1282c19:dd:ec00:c25:c25e:dd:ddea:e2c
462c19:dd:ec00:c25:c25e:dd:ddea:e2d/1282c19:dd:ec00:c25:c25e:dd:ddea:e2d
472c19:dd:ec00:c25:c25e:dd:ddea:e2e/1282c19:dd:ec00:c25:c25e:dd:ddea:e2e
482c19:dd:ec00:c25:c25e:dd:ddea:e2f/1282c19:dd:ec00:c25:c25e:dd:ddea:e2f
492c19:dd:ec00:c25:c25e:dd:ddea:e30/1282c19:dd:ec00:c25:c25e:dd:ddea:e30
502c19:dd:ec00:c25:c25e:dd:ddea:e31/1282c19:dd:ec00:c25:c25e:dd:ddea:e31
512c19:dd:ec00:c25:c25e:dd:ddea:e32/1282c19:dd:ec00:c25:c25e:dd:ddea:e32
522c19:dd:ec00:c25:c25e:dd:ddea:e33/1282c19:dd:ec00:c25:c25e:dd:ddea:e33
532c19:dd:ec00:c25:c25e:dd:ddea:e34/1282c19:dd:ec00:c25:c25e:dd:ddea:e34
542c19:dd:ec00:c25:c25e:dd:ddea:e35/1282c19:dd:ec00:c25:c25e:dd:ddea:e35
552c19:dd:ec00:c25:c25e:dd:ddea:e36/1282c19:dd:ec00:c25:c25e:dd:ddea:e36
562c19:dd:ec00:c25:c25e:dd:ddea:e37/1282c19:dd:ec00:c25:c25e:dd:ddea:e37
572c19:dd:ec00:c25:c25e:dd:ddea:e38/1282c19:dd:ec00:c25:c25e:dd:ddea:e38
582c19:dd:ec00:c25:c25e:dd:ddea:e39/1282c19:dd:ec00:c25:c25e:dd:ddea:e39
592c19:dd:ec00:c25:c25e:dd:ddea:e3a/1282c19:dd:ec00:c25:c25e:dd:ddea:e3a
602c19:dd:ec00:c25:c25e:dd:ddea:e3b/1282c19:dd:ec00:c25:c25e:dd:ddea:e3b
612c19:dd:ec00:c25:c25e:dd:ddea:e3c/1282c19:dd:ec00:c25:c25e:dd:ddea:e3c
622c19:dd:ec00:c25:c25e:dd:ddea:e3d/1282c19:dd:ec00:c25:c25e:dd:ddea:e3d
632c19:dd:ec00:c25:c25e:dd:ddea:e3e/1282c19:dd:ec00:c25:c25e:dd:ddea:e3e
642c19:dd:ec00:c25:c25e:dd:ddea:e3f/1282c19:dd:ec00:c25:c25e:dd:ddea:e3f
652c19:dd:ec00:c25:c25e:dd:ddea:e40/1282c19:dd:ec00:c25:c25e:dd:ddea:e40
662c19:dd:ec00:c25:c25e:dd:ddea:e41/1282c19:dd:ec00:c25:c25e:dd:ddea:e41
672c19:dd:ec00:c25:c25e:dd:ddea:e42/1282c19:dd:ec00:c25:c25e:dd:ddea:e42
682c19:dd:ec00:c25:c25e:dd:ddea:e43/1282c19:dd:ec00:c25:c25e:dd:ddea:e43
692c19:dd:ec00:c25:c25e:dd:ddea:e44/1282c19:dd:ec00:c25:c25e:dd:ddea:e44
702c19:dd:ec00:c25:c25e:dd:ddea:e45/1282c19:dd:ec00:c25:c25e:dd:ddea:e45
712c19:dd:ec00:c25:c25e:dd:ddea:e46/1282c19:dd:ec00:c25:c25e:dd:ddea:e46
722c19:dd:ec00:c25:c25e:dd:ddea:e47/1282c19:dd:ec00:c25:c25e:dd:ddea:e47
732c19:dd:ec00:c25:c25e:dd:ddea:e48/1282c19:dd:ec00:c25:c25e:dd:ddea:e48
742c19:dd:ec00:c25:c25e:dd:ddea:e49/1282c19:dd:ec00:c25:c25e:dd:ddea:e49
752c19:dd:ec00:c25:c25e:dd:ddea:e4a/1282c19:dd:ec00:c25:c25e:dd:ddea:e4a
762c19:dd:ec00:c25:c25e:dd:ddea:e4b/1282c19:dd:ec00:c25:c25e:dd:ddea:e4b
772c19:dd:ec00:c25:c25e:dd:ddea:e4c/1282c19:dd:ec00:c25:c25e:dd:ddea:e4c
782c19:dd:ec00:c25:c25e:dd:ddea:e4d/1282c19:dd:ec00:c25:c25e:dd:ddea:e4d
792c19:dd:ec00:c25:c25e:dd:ddea:e4e/1282c19:dd:ec00:c25:c25e:dd:ddea:e4e
802c19:dd:ec00:c25:c25e:dd:ddea:e4f/1282c19:dd:ec00:c25:c25e:dd:ddea:e4f
812c19:dd:ec00:c25:c25e:dd:ddea:e50/1282c19:dd:ec00:c25:c25e:dd:ddea:e50
822c19:dd:ec00:c25:c25e:dd:ddea:e51/1282c19:dd:ec00:c25:c25e:dd:ddea:e51
832c19:dd:ec00:c25:c25e:dd:ddea:e52/1282c19:dd:ec00:c25:c25e:dd:ddea:e52
842c19:dd:ec00:c25:c25e:dd:ddea:e53/1282c19:dd:ec00:c25:c25e:dd:ddea:e53
852c19:dd:ec00:c25:c25e:dd:ddea:e54/1282c19:dd:ec00:c25:c25e:dd:ddea:e54
862c19:dd:ec00:c25:c25e:dd:ddea:e55/1282c19:dd:ec00:c25:c25e:dd:ddea:e55
872c19:dd:ec00:c25:c25e:dd:ddea:e56/1282c19:dd:ec00:c25:c25e:dd:ddea:e56
882c19:dd:ec00:c25:c25e:dd:ddea:e57/1282c19:dd:ec00:c25:c25e:dd:ddea:e57
892c19:dd:ec00:c25:c25e:dd:ddea:e58/1282c19:dd:ec00:c25:c25e:dd:ddea:e58
902c19:dd:ec00:c25:c25e:dd:ddea:e59/1282c19:dd:ec00:c25:c25e:dd:ddea:e59
912c19:dd:ec00:c25:c25e:dd:ddea:e5a/1282c19:dd:ec00:c25:c25e:dd:ddea:e5a
922c19:dd:ec00:c25:c25e:dd:ddea:e5b/1282c19:dd:ec00:c25:c25e:dd:ddea:e5b
932c19:dd:ec00:c25:c25e:dd:ddea:e5c/1282c19:dd:ec00:c25:c25e:dd:ddea:e5c
942c19:dd:ec00:c25:c25e:dd:ddea:e5d/1282c19:dd:ec00:c25:c25e:dd:ddea:e5d
952c19:dd:ec00:c25:c25e:dd:ddea:e5e/1282c19:dd:ec00:c25:c25e:dd:ddea:e5e
962c19:dd:ec00:c25:c25e:dd:ddea:e5f/1282c19:dd:ec00:c25:c25e:dd:ddea:e5f
972c19:dd:ec00:c25:c25e:dd:ddea:e60/1282c19:dd:ec00:c25:c25e:dd:ddea:e60
982c19:dd:ec00:c25:c25e:dd:ddea:e61/1282c19:dd:ec00:c25:c25e:dd:ddea:e61
992c19:dd:ec00:c25:c25e:dd:ddea:e62/1282c19:dd:ec00:c25:c25e:dd:ddea:e62
1002c19:dd:ec00:c25:c25e:dd:ddea:e63/1282c19:dd:ec00:c25:c25e:dd:ddea:e63
1012c19:dd:ec00:c25:c25e:dd:ddea:e64/1282c19:dd:ec00:c25:c25e:dd:ddea:e64
1022c19:dd:ec00:c25:c25e:dd:ddea:e65/1282c19:dd:ec00:c25:c25e:dd:ddea:e65
1032c19:dd:ec00:c25:c25e:dd:ddea:e66/1282c19:dd:ec00:c25:c25e:dd:ddea:e66
1042c19:dd:ec00:c25:c25e:dd:ddea:e67/1282c19:dd:ec00:c25:c25e:dd:ddea:e67
1052c19:dd:ec00:c25:c25e:dd:ddea:e68/1282c19:dd:ec00:c25:c25e:dd:ddea:e68
1062c19:dd:ec00:c25:c25e:dd:ddea:e69/1282c19:dd:ec00:c25:c25e:dd:ddea:e69
1072c19:dd:ec00:c25:c25e:dd:ddea:e6a/1282c19:dd:ec00:c25:c25e:dd:ddea:e6a
1082c19:dd:ec00:c25:c25e:dd:ddea:e6b/1282c19:dd:ec00:c25:c25e:dd:ddea:e6b
1092c19:dd:ec00:c25:c25e:dd:ddea:e6c/1282c19:dd:ec00:c25:c25e:dd:ddea:e6c
1102c19:dd:ec00:c25:c25e:dd:ddea:e6d/1282c19:dd:ec00:c25:c25e:dd:ddea:e6d
1112c19:dd:ec00:c25:c25e:dd:ddea:e6e/1282c19:dd:ec00:c25:c25e:dd:ddea:e6e
1122c19:dd:ec00:c25:c25e:dd:ddea:e6f/1282c19:dd:ec00:c25:c25e:dd:ddea:e6f
1132c19:dd:ec00:c25:c25e:dd:ddea:e70/1282c19:dd:ec00:c25:c25e:dd:ddea:e70
1142c19:dd:ec00:c25:c25e:dd:ddea:e71/1282c19:dd:ec00:c25:c25e:dd:ddea:e71
1152c19:dd:ec00:c25:c25e:dd:ddea:e72/1282c19:dd:ec00:c25:c25e:dd:ddea:e72
1162c19:dd:ec00:c25:c25e:dd:ddea:e73/1282c19:dd:ec00:c25:c25e:dd:ddea:e73
1172c19:dd:ec00:c25:c25e:dd:ddea:e74/1282c19:dd:ec00:c25:c25e:dd:ddea:e74
1182c19:dd:ec00:c25:c25e:dd:ddea:e75/1282c19:dd:ec00:c25:c25e:dd:ddea:e75
1192c19:dd:ec00:c25:c25e:dd:ddea:e76/1282c19:dd:ec00:c25:c25e:dd:ddea:e76
1202c19:dd:ec00:c25:c25e:dd:ddea:e77/1282c19:dd:ec00:c25:c25e:dd:ddea:e77
1212c19:dd:ec00:c25:c25e:dd:ddea:e78/1282c19:dd:ec00:c25:c25e:dd:ddea:e78
1222c19:dd:ec00:c25:c25e:dd:ddea:e79/1282c19:dd:ec00:c25:c25e:dd:ddea:e79
1232c19:dd:ec00:c25:c25e:dd:ddea:e7a/1282c19:dd:ec00:c25:c25e:dd:ddea:e7a
1242c19:dd:ec00:c25:c25e:dd:ddea:e7b/1282c19:dd:ec00:c25:c25e:dd:ddea:e7b
1252c19:dd:ec00:c25:c25e:dd:ddea:e7c/1282c19:dd:ec00:c25:c25e:dd:ddea:e7c
1262c19:dd:ec00:c25:c25e:dd:ddea:e7d/1282c19:dd:ec00:c25:c25e:dd:ddea:e7d
1272c19:dd:ec00:c25:c25e:dd:ddea:e7e/1282c19:dd:ec00:c25:c25e:dd:ddea:e7e
1282c19:dd:ec00:c25:c25e:dd:ddea:e7f/1282c19:dd:ec00:c25:c25e:dd:ddea:e7f
1292c19:dd:ec00:c25:c25e:dd:ddea:e80/1282c19:dd:ec00:c25:c25e:dd:ddea:e80
1302c19:dd:ec00:c25:c25e:dd:ddea:e81/1282c19:dd:ec00:c25:c25e:dd:ddea:e81
1312c19:dd:ec00:c25:c25e:dd:ddea:e82/1282c19:dd:ec00:c25:c25e:dd:ddea:e82
1322c19:dd:ec00:c25:c25e:dd:ddea:e83/1282c19:dd:ec00:c25:c25e:dd:ddea:e83
1332c19:dd:ec00:c25:c25e:dd:ddea:e84/1282c19:dd:ec00:c25:c25e:dd:ddea:e84
1342c19:dd:ec00:c25:c25e:dd:ddea:e85/1282c19:dd:ec00:c25:c25e:dd:ddea:e85
1352c19:dd:ec00:c25:c25e:dd:ddea:e86/1282c19:dd:ec00:c25:c25e:dd:ddea:e86
1362c19:dd:ec00:c25:c25e:dd:ddea:e87/1282c19:dd:ec00:c25:c25e:dd:ddea:e87
1372c19:dd:ec00:c25:c25e:dd:ddea:e88/1282c19:dd:ec00:c25:c25e:dd:ddea:e88
1382c19:dd:ec00:c25:c25e:dd:ddea:e89/1282c19:dd:ec00:c25:c25e:dd:ddea:e89
1392c19:dd:ec00:c25:c25e:dd:ddea:e8a/1282c19:dd:ec00:c25:c25e:dd:ddea:e8a
1402c19:dd:ec00:c25:c25e:dd:ddea:e8b/1282c19:dd:ec00:c25:c25e:dd:ddea:e8b
1412c19:dd:ec00:c25:c25e:dd:ddea:e8c/1282c19:dd:ec00:c25:c25e:dd:ddea:e8c
1422c19:dd:ec00:c25:c25e:dd:ddea:e8d/1282c19:dd:ec00:c25:c25e:dd:ddea:e8d
1432c19:dd:ec00:c25:c25e:dd:ddea:e8e/1282c19:dd:ec00:c25:c25e:dd:ddea:e8e
1442c19:dd:ec00:c25:c25e:dd:ddea:e8f/1282c19:dd:ec00:c25:c25e:dd:ddea:e8f
1452c19:dd:ec00:c25:c25e:dd:ddea:e90/1282c19:dd:ec00:c25:c25e:dd:ddea:e90
1462c19:dd:ec00:c25:c25e:dd:ddea:e91/1282c19:dd:ec00:c25:c25e:dd:ddea:e91
1472c19:dd:ec00:c25:c25e:dd:ddea:e92/1282c19:dd:ec00:c25:c25e:dd:ddea:e92
1482c19:dd:ec00:c25:c25e:dd:ddea:e93/1282c19:dd:ec00:c25:c25e:dd:ddea:e93
1492c19:dd:ec00:c25:c25e:dd:ddea:e94/1282c19:dd:ec00:c25:c25e:dd:ddea:e94
1502c19:dd:ec00:c25:c25e:dd:ddea:e95/1282c19:dd:ec00:c25:c25e:dd:ddea:e95
1512c19:dd:ec00:c25:c25e:dd:ddea:e96/1282c19:dd:ec00:c25:c25e:dd:ddea:e96
1522c19:dd:ec00:c25:c25e:dd:ddea:e97/1282c19:dd:ec00:c25:c25e:dd:ddea:e97
1532c19:dd:ec00:c25:c25e:dd:ddea:e98/1282c19:dd:ec00:c25:c25e:dd:ddea:e98
1542c19:dd:ec00:c25:c25e:dd:ddea:e99/1282c19:dd:ec00:c25:c25e:dd:ddea:e99
1552c19:dd:ec00:c25:c25e:dd:ddea:e9a/1282c19:dd:ec00:c25:c25e:dd:ddea:e9a
1562c19:dd:ec00:c25:c25e:dd:ddea:e9b/1282c19:dd:ec00:c25:c25e:dd:ddea:e9b
1572c19:dd:ec00:c25:c25e:dd:ddea:e9c/1282c19:dd:ec00:c25:c25e:dd:ddea:e9c
1582c19:dd:ec00:c25:c25e:dd:ddea:e9d/1282c19:dd:ec00:c25:c25e:dd:ddea:e9d
1592c19:dd:ec00:c25:c25e:dd:ddea:e9e/1282c19:dd:ec00:c25:c25e:dd:ddea:e9e
1602c19:dd:ec00:c25:c25e:dd:ddea:e9f/1282c19:dd:ec00:c25:c25e:dd:ddea:e9f
1612c19:dd:ec00:c25:c25e:dd:ddea:ea0/1282c19:dd:ec00:c25:c25e:dd:ddea:ea0
1622c19:dd:ec00:c25:c25e:dd:ddea:ea1/1282c19:dd:ec00:c25:c25e:dd:ddea:ea1
1632c19:dd:ec00:c25:c25e:dd:ddea:ea2/1282c19:dd:ec00:c25:c25e:dd:ddea:ea2
1642c19:dd:ec00:c25:c25e:dd:ddea:ea3/1282c19:dd:ec00:c25:c25e:dd:ddea:ea3
1652c19:dd:ec00:c25:c25e:dd:ddea:ea4/1282c19:dd:ec00:c25:c25e:dd:ddea:ea4
1662c19:dd:ec00:c25:c25e:dd:ddea:ea5/1282c19:dd:ec00:c25:c25e:dd:ddea:ea5
1672c19:dd:ec00:c25:c25e:dd:ddea:ea6/1282c19:dd:ec00:c25:c25e:dd:ddea:ea6
1682c19:dd:ec00:c25:c25e:dd:ddea:ea7/1282c19:dd:ec00:c25:c25e:dd:ddea:ea7
1692c19:dd:ec00:c25:c25e:dd:ddea:ea8/1282c19:dd:ec00:c25:c25e:dd:ddea:ea8
1702c19:dd:ec00:c25:c25e:dd:ddea:ea9/1282c19:dd:ec00:c25:c25e:dd:ddea:ea9
1712c19:dd:ec00:c25:c25e:dd:ddea:eaa/1282c19:dd:ec00:c25:c25e:dd:ddea:eaa
1722c19:dd:ec00:c25:c25e:dd:ddea:eab/1282c19:dd:ec00:c25:c25e:dd:ddea:eab
1732c19:dd:ec00:c25:c25e:dd:ddea:eac/1282c19:dd:ec00:c25:c25e:dd:ddea:eac
1742c19:dd:ec00:c25:c25e:dd:ddea:ead/1282c19:dd:ec00:c25:c25e:dd:ddea:ead
1752c19:dd:ec00:c25:c25e:dd:ddea:eae/1282c19:dd:ec00:c25:c25e:dd:ddea:eae
1762c19:dd:ec00:c25:c25e:dd:ddea:eaf/1282c19:dd:ec00:c25:c25e:dd:ddea:eaf
1772c19:dd:ec00:c25:c25e:dd:ddea:eb0/1282c19:dd:ec00:c25:c25e:dd:ddea:eb0
1782c19:dd:ec00:c25:c25e:dd:ddea:eb1/1282c19:dd:ec00:c25:c25e:dd:ddea:eb1
1792c19:dd:ec00:c25:c25e:dd:ddea:eb2/1282c19:dd:ec00:c25:c25e:dd:ddea:eb2
1802c19:dd:ec00:c25:c25e:dd:ddea:eb3/1282c19:dd:ec00:c25:c25e:dd:ddea:eb3
1812c19:dd:ec00:c25:c25e:dd:ddea:eb4/1282c19:dd:ec00:c25:c25e:dd:ddea:eb4
1822c19:dd:ec00:c25:c25e:dd:ddea:eb5/1282c19:dd:ec00:c25:c25e:dd:ddea:eb5
1832c19:dd:ec00:c25:c25e:dd:ddea:eb6/1282c19:dd:ec00:c25:c25e:dd:ddea:eb6
1842c19:dd:ec00:c25:c25e:dd:ddea:eb7/1282c19:dd:ec00:c25:c25e:dd:ddea:eb7
1852c19:dd:ec00:c25:c25e:dd:ddea:eb8/1282c19:dd:ec00:c25:c25e:dd:ddea:eb8
1862c19:dd:ec00:c25:c25e:dd:ddea:eb9/1282c19:dd:ec00:c25:c25e:dd:ddea:eb9
1872c19:dd:ec00:c25:c25e:dd:ddea:eba/1282c19:dd:ec00:c25:c25e:dd:ddea:eba
1882c19:dd:ec00:c25:c25e:dd:ddea:ebb/1282c19:dd:ec00:c25:c25e:dd:ddea:ebb
1892c19:dd:ec00:c25:c25e:dd:ddea:ebc/1282c19:dd:ec00:c25:c25e:dd:ddea:ebc
1902c19:dd:ec00:c25:c25e:dd:ddea:ebd/1282c19:dd:ec00:c25:c25e:dd:ddea:ebd
1912c19:dd:ec00:c25:c25e:dd:ddea:ebe/1282c19:dd:ec00:c25:c25e:dd:ddea:ebe
1922c19:dd:ec00:c25:c25e:dd:ddea:ebf/1282c19:dd:ec00:c25:c25e:dd:ddea:ebf
1932c19:dd:ec00:c25:c25e:dd:ddea:ec0/1282c19:dd:ec00:c25:c25e:dd:ddea:ec0
1942c19:dd:ec00:c25:c25e:dd:ddea:ec1/1282c19:dd:ec00:c25:c25e:dd:ddea:ec1
1952c19:dd:ec00:c25:c25e:dd:ddea:ec2/1282c19:dd:ec00:c25:c25e:dd:ddea:ec2
1962c19:dd:ec00:c25:c25e:dd:ddea:ec3/1282c19:dd:ec00:c25:c25e:dd:ddea:ec3
1972c19:dd:ec00:c25:c25e:dd:ddea:ec4/1282c19:dd:ec00:c25:c25e:dd:ddea:ec4
1982c19:dd:ec00:c25:c25e:dd:ddea:ec5/1282c19:dd:ec00:c25:c25e:dd:ddea:ec5
1992c19:dd:ec00:c25:c25e:dd:ddea:ec6/1282c19:dd:ec00:c25:c25e:dd:ddea:ec6
2002c19:dd:ec00:c25:c25e:dd:ddea:ec7/1282c19:dd:ec00:c25:c25e:dd:ddea:ec7
2012c19:dd:ec00:c25:c25e:dd:ddea:ec8/1282c19:dd:ec00:c25:c25e:dd:ddea:ec8
2022c19:dd:ec00:c25:c25e:dd:ddea:ec9/1282c19:dd:ec00:c25:c25e:dd:ddea:ec9
2032c19:dd:ec00:c25:c25e:dd:ddea:eca/1282c19:dd:ec00:c25:c25e:dd:ddea:eca
2042c19:dd:ec00:c25:c25e:dd:ddea:ecb/1282c19:dd:ec00:c25:c25e:dd:ddea:ecb
2052c19:dd:ec00:c25:c25e:dd:ddea:ecc/1282c19:dd:ec00:c25:c25e:dd:ddea:ecc
2062c19:dd:ec00:c25:c25e:dd:ddea:ecd/1282c19:dd:ec00:c25:c25e:dd:ddea:ecd
2072c19:dd:ec00:c25:c25e:dd:ddea:ece/1282c19:dd:ec00:c25:c25e:dd:ddea:ece
2082c19:dd:ec00:c25:c25e:dd:ddea:ecf/1282c19:dd:ec00:c25:c25e:dd:ddea:ecf
2092c19:dd:ec00:c25:c25e:dd:ddea:ed0/1282c19:dd:ec00:c25:c25e:dd:ddea:ed0
2102c19:dd:ec00:c25:c25e:dd:ddea:ed1/1282c19:dd:ec00:c25:c25e:dd:ddea:ed1
2112c19:dd:ec00:c25:c25e:dd:ddea:ed2/1282c19:dd:ec00:c25:c25e:dd:ddea:ed2
2122c19:dd:ec00:c25:c25e:dd:ddea:ed3/1282c19:dd:ec00:c25:c25e:dd:ddea:ed3
2132c19:dd:ec00:c25:c25e:dd:ddea:ed4/1282c19:dd:ec00:c25:c25e:dd:ddea:ed4
2142c19:dd:ec00:c25:c25e:dd:ddea:ed5/1282c19:dd:ec00:c25:c25e:dd:ddea:ed5
2152c19:dd:ec00:c25:c25e:dd:ddea:ed6/1282c19:dd:ec00:c25:c25e:dd:ddea:ed6
2162c19:dd:ec00:c25:c25e:dd:ddea:ed7/1282c19:dd:ec00:c25:c25e:dd:ddea:ed7
2172c19:dd:ec00:c25:c25e:dd:ddea:ed8/1282c19:dd:ec00:c25:c25e:dd:ddea:ed8
2182c19:dd:ec00:c25:c25e:dd:ddea:ed9/1282c19:dd:ec00:c25:c25e:dd:ddea:ed9
2192c19:dd:ec00:c25:c25e:dd:ddea:eda/1282c19:dd:ec00:c25:c25e:dd:ddea:eda
2202c19:dd:ec00:c25:c25e:dd:ddea:edb/1282c19:dd:ec00:c25:c25e:dd:ddea:edb
2212c19:dd:ec00:c25:c25e:dd:ddea:edc/1282c19:dd:ec00:c25:c25e:dd:ddea:edc
2222c19:dd:ec00:c25:c25e:dd:ddea:edd/1282c19:dd:ec00:c25:c25e:dd:ddea:edd
2232c19:dd:ec00:c25:c25e:dd:ddea:ede/1282c19:dd:ec00:c25:c25e:dd:ddea:ede
2242c19:dd:ec00:c25:c25e:dd:ddea:edf/1282c19:dd:ec00:c25:c25e:dd:ddea:edf
2252c19:dd:ec00:c25:c25e:dd:ddea:ee0/1282c19:dd:ec00:c25:c25e:dd:ddea:ee0
2262c19:dd:ec00:c25:c25e:dd:ddea:ee1/1282c19:dd:ec00:c25:c25e:dd:ddea:ee1
2272c19:dd:ec00:c25:c25e:dd:ddea:ee2/1282c19:dd:ec00:c25:c25e:dd:ddea:ee2
2282c19:dd:ec00:c25:c25e:dd:ddea:ee3/1282c19:dd:ec00:c25:c25e:dd:ddea:ee3
2292c19:dd:ec00:c25:c25e:dd:ddea:ee4/1282c19:dd:ec00:c25:c25e:dd:ddea:ee4
2302c19:dd:ec00:c25:c25e:dd:ddea:ee5/1282c19:dd:ec00:c25:c25e:dd:ddea:ee5
2312c19:dd:ec00:c25:c25e:dd:ddea:ee6/1282c19:dd:ec00:c25:c25e:dd:ddea:ee6
2322c19:dd:ec00:c25:c25e:dd:ddea:ee7/1282c19:dd:ec00:c25:c25e:dd:ddea:ee7
2332c19:dd:ec00:c25:c25e:dd:ddea:ee8/1282c19:dd:ec00:c25:c25e:dd:ddea:ee8
2342c19:dd:ec00:c25:c25e:dd:ddea:ee9/1282c19:dd:ec00:c25:c25e:dd:ddea:ee9
2352c19:dd:ec00:c25:c25e:dd:ddea:eea/1282c19:dd:ec00:c25:c25e:dd:ddea:eea
2362c19:dd:ec00:c25:c25e:dd:ddea:eeb/1282c19:dd:ec00:c25:c25e:dd:ddea:eeb
2372c19:dd:ec00:c25:c25e:dd:ddea:eec/1282c19:dd:ec00:c25:c25e:dd:ddea:eec
2382c19:dd:ec00:c25:c25e:dd:ddea:eed/1282c19:dd:ec00:c25:c25e:dd:ddea:eed
2392c19:dd:ec00:c25:c25e:dd:ddea:eee/1282c19:dd:ec00:c25:c25e:dd:ddea:eee
2402c19:dd:ec00:c25:c25e:dd:ddea:eef/1282c19:dd:ec00:c25:c25e:dd:ddea:eef
2412c19:dd:ec00:c25:c25e:dd:ddea:ef0/1282c19:dd:ec00:c25:c25e:dd:ddea:ef0
2422c19:dd:ec00:c25:c25e:dd:ddea:ef1/1282c19:dd:ec00:c25:c25e:dd:ddea:ef1
2432c19:dd:ec00:c25:c25e:dd:ddea:ef2/1282c19:dd:ec00:c25:c25e:dd:ddea:ef2
2442c19:dd:ec00:c25:c25e:dd:ddea:ef3/1282c19:dd:ec00:c25:c25e:dd:ddea:ef3
2452c19:dd:ec00:c25:c25e:dd:ddea:ef4/1282c19:dd:ec00:c25:c25e:dd:ddea:ef4
2462c19:dd:ec00:c25:c25e:dd:ddea:ef5/1282c19:dd:ec00:c25:c25e:dd:ddea:ef5
2472c19:dd:ec00:c25:c25e:dd:ddea:ef6/1282c19:dd:ec00:c25:c25e:dd:ddea:ef6
2482c19:dd:ec00:c25:c25e:dd:ddea:ef7/1282c19:dd:ec00:c25:c25e:dd:ddea:ef7
2492c19:dd:ec00:c25:c25e:dd:ddea:ef8/1282c19:dd:ec00:c25:c25e:dd:ddea:ef8
2502c19:dd:ec00:c25:c25e:dd:ddea:ef9/1282c19:dd:ec00:c25:c25e:dd:ddea:ef9
2512c19:dd:ec00:c25:c25e:dd:ddea:efa/1282c19:dd:ec00:c25:c25e:dd:ddea:efa
2522c19:dd:ec00:c25:c25e:dd:ddea:efb/1282c19:dd:ec00:c25:c25e:dd:ddea:efb
2532c19:dd:ec00:c25:c25e:dd:ddea:efc/1282c19:dd:ec00:c25:c25e:dd:ddea:efc
2542c19:dd:ec00:c25:c25e:dd:ddea:efd/1282c19:dd:ec00:c25:c25e:dd:ddea:efd
2552c19:dd:ec00:c25:c25e:dd:ddea:efe/1282c19:dd:ec00:c25:c25e:dd:ddea:efe
2562c19:dd:ec00:c25:c25e:dd:ddea:eff/1282c19:dd:ec00:c25:c25e:dd:ddea:eff

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.