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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:6c00/120
First address
2c19:dd:d9:dd:c25:c25:94de:6c00
Last address
2c19:dd:d9:dd:c25:c25:94de:6cff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:6c00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
c.6.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:6c00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:6c00/1282c19:dd:d9:dd:c25:c25:94de:6c00
22c19:dd:d9:dd:c25:c25:94de:6c01/1282c19:dd:d9:dd:c25:c25:94de:6c01
32c19:dd:d9:dd:c25:c25:94de:6c02/1282c19:dd:d9:dd:c25:c25:94de:6c02
42c19:dd:d9:dd:c25:c25:94de:6c03/1282c19:dd:d9:dd:c25:c25:94de:6c03
52c19:dd:d9:dd:c25:c25:94de:6c04/1282c19:dd:d9:dd:c25:c25:94de:6c04
62c19:dd:d9:dd:c25:c25:94de:6c05/1282c19:dd:d9:dd:c25:c25:94de:6c05
72c19:dd:d9:dd:c25:c25:94de:6c06/1282c19:dd:d9:dd:c25:c25:94de:6c06
82c19:dd:d9:dd:c25:c25:94de:6c07/1282c19:dd:d9:dd:c25:c25:94de:6c07
92c19:dd:d9:dd:c25:c25:94de:6c08/1282c19:dd:d9:dd:c25:c25:94de:6c08
102c19:dd:d9:dd:c25:c25:94de:6c09/1282c19:dd:d9:dd:c25:c25:94de:6c09
112c19:dd:d9:dd:c25:c25:94de:6c0a/1282c19:dd:d9:dd:c25:c25:94de:6c0a
122c19:dd:d9:dd:c25:c25:94de:6c0b/1282c19:dd:d9:dd:c25:c25:94de:6c0b
132c19:dd:d9:dd:c25:c25:94de:6c0c/1282c19:dd:d9:dd:c25:c25:94de:6c0c
142c19:dd:d9:dd:c25:c25:94de:6c0d/1282c19:dd:d9:dd:c25:c25:94de:6c0d
152c19:dd:d9:dd:c25:c25:94de:6c0e/1282c19:dd:d9:dd:c25:c25:94de:6c0e
162c19:dd:d9:dd:c25:c25:94de:6c0f/1282c19:dd:d9:dd:c25:c25:94de:6c0f
172c19:dd:d9:dd:c25:c25:94de:6c10/1282c19:dd:d9:dd:c25:c25:94de:6c10
182c19:dd:d9:dd:c25:c25:94de:6c11/1282c19:dd:d9:dd:c25:c25:94de:6c11
192c19:dd:d9:dd:c25:c25:94de:6c12/1282c19:dd:d9:dd:c25:c25:94de:6c12
202c19:dd:d9:dd:c25:c25:94de:6c13/1282c19:dd:d9:dd:c25:c25:94de:6c13
212c19:dd:d9:dd:c25:c25:94de:6c14/1282c19:dd:d9:dd:c25:c25:94de:6c14
222c19:dd:d9:dd:c25:c25:94de:6c15/1282c19:dd:d9:dd:c25:c25:94de:6c15
232c19:dd:d9:dd:c25:c25:94de:6c16/1282c19:dd:d9:dd:c25:c25:94de:6c16
242c19:dd:d9:dd:c25:c25:94de:6c17/1282c19:dd:d9:dd:c25:c25:94de:6c17
252c19:dd:d9:dd:c25:c25:94de:6c18/1282c19:dd:d9:dd:c25:c25:94de:6c18
262c19:dd:d9:dd:c25:c25:94de:6c19/1282c19:dd:d9:dd:c25:c25:94de:6c19
272c19:dd:d9:dd:c25:c25:94de:6c1a/1282c19:dd:d9:dd:c25:c25:94de:6c1a
282c19:dd:d9:dd:c25:c25:94de:6c1b/1282c19:dd:d9:dd:c25:c25:94de:6c1b
292c19:dd:d9:dd:c25:c25:94de:6c1c/1282c19:dd:d9:dd:c25:c25:94de:6c1c
302c19:dd:d9:dd:c25:c25:94de:6c1d/1282c19:dd:d9:dd:c25:c25:94de:6c1d
312c19:dd:d9:dd:c25:c25:94de:6c1e/1282c19:dd:d9:dd:c25:c25:94de:6c1e
322c19:dd:d9:dd:c25:c25:94de:6c1f/1282c19:dd:d9:dd:c25:c25:94de:6c1f
332c19:dd:d9:dd:c25:c25:94de:6c20/1282c19:dd:d9:dd:c25:c25:94de:6c20
342c19:dd:d9:dd:c25:c25:94de:6c21/1282c19:dd:d9:dd:c25:c25:94de:6c21
352c19:dd:d9:dd:c25:c25:94de:6c22/1282c19:dd:d9:dd:c25:c25:94de:6c22
362c19:dd:d9:dd:c25:c25:94de:6c23/1282c19:dd:d9:dd:c25:c25:94de:6c23
372c19:dd:d9:dd:c25:c25:94de:6c24/1282c19:dd:d9:dd:c25:c25:94de:6c24
382c19:dd:d9:dd:c25:c25:94de:6c25/1282c19:dd:d9:dd:c25:c25:94de:6c25
392c19:dd:d9:dd:c25:c25:94de:6c26/1282c19:dd:d9:dd:c25:c25:94de:6c26
402c19:dd:d9:dd:c25:c25:94de:6c27/1282c19:dd:d9:dd:c25:c25:94de:6c27
412c19:dd:d9:dd:c25:c25:94de:6c28/1282c19:dd:d9:dd:c25:c25:94de:6c28
422c19:dd:d9:dd:c25:c25:94de:6c29/1282c19:dd:d9:dd:c25:c25:94de:6c29
432c19:dd:d9:dd:c25:c25:94de:6c2a/1282c19:dd:d9:dd:c25:c25:94de:6c2a
442c19:dd:d9:dd:c25:c25:94de:6c2b/1282c19:dd:d9:dd:c25:c25:94de:6c2b
452c19:dd:d9:dd:c25:c25:94de:6c2c/1282c19:dd:d9:dd:c25:c25:94de:6c2c
462c19:dd:d9:dd:c25:c25:94de:6c2d/1282c19:dd:d9:dd:c25:c25:94de:6c2d
472c19:dd:d9:dd:c25:c25:94de:6c2e/1282c19:dd:d9:dd:c25:c25:94de:6c2e
482c19:dd:d9:dd:c25:c25:94de:6c2f/1282c19:dd:d9:dd:c25:c25:94de:6c2f
492c19:dd:d9:dd:c25:c25:94de:6c30/1282c19:dd:d9:dd:c25:c25:94de:6c30
502c19:dd:d9:dd:c25:c25:94de:6c31/1282c19:dd:d9:dd:c25:c25:94de:6c31
512c19:dd:d9:dd:c25:c25:94de:6c32/1282c19:dd:d9:dd:c25:c25:94de:6c32
522c19:dd:d9:dd:c25:c25:94de:6c33/1282c19:dd:d9:dd:c25:c25:94de:6c33
532c19:dd:d9:dd:c25:c25:94de:6c34/1282c19:dd:d9:dd:c25:c25:94de:6c34
542c19:dd:d9:dd:c25:c25:94de:6c35/1282c19:dd:d9:dd:c25:c25:94de:6c35
552c19:dd:d9:dd:c25:c25:94de:6c36/1282c19:dd:d9:dd:c25:c25:94de:6c36
562c19:dd:d9:dd:c25:c25:94de:6c37/1282c19:dd:d9:dd:c25:c25:94de:6c37
572c19:dd:d9:dd:c25:c25:94de:6c38/1282c19:dd:d9:dd:c25:c25:94de:6c38
582c19:dd:d9:dd:c25:c25:94de:6c39/1282c19:dd:d9:dd:c25:c25:94de:6c39
592c19:dd:d9:dd:c25:c25:94de:6c3a/1282c19:dd:d9:dd:c25:c25:94de:6c3a
602c19:dd:d9:dd:c25:c25:94de:6c3b/1282c19:dd:d9:dd:c25:c25:94de:6c3b
612c19:dd:d9:dd:c25:c25:94de:6c3c/1282c19:dd:d9:dd:c25:c25:94de:6c3c
622c19:dd:d9:dd:c25:c25:94de:6c3d/1282c19:dd:d9:dd:c25:c25:94de:6c3d
632c19:dd:d9:dd:c25:c25:94de:6c3e/1282c19:dd:d9:dd:c25:c25:94de:6c3e
642c19:dd:d9:dd:c25:c25:94de:6c3f/1282c19:dd:d9:dd:c25:c25:94de:6c3f
652c19:dd:d9:dd:c25:c25:94de:6c40/1282c19:dd:d9:dd:c25:c25:94de:6c40
662c19:dd:d9:dd:c25:c25:94de:6c41/1282c19:dd:d9:dd:c25:c25:94de:6c41
672c19:dd:d9:dd:c25:c25:94de:6c42/1282c19:dd:d9:dd:c25:c25:94de:6c42
682c19:dd:d9:dd:c25:c25:94de:6c43/1282c19:dd:d9:dd:c25:c25:94de:6c43
692c19:dd:d9:dd:c25:c25:94de:6c44/1282c19:dd:d9:dd:c25:c25:94de:6c44
702c19:dd:d9:dd:c25:c25:94de:6c45/1282c19:dd:d9:dd:c25:c25:94de:6c45
712c19:dd:d9:dd:c25:c25:94de:6c46/1282c19:dd:d9:dd:c25:c25:94de:6c46
722c19:dd:d9:dd:c25:c25:94de:6c47/1282c19:dd:d9:dd:c25:c25:94de:6c47
732c19:dd:d9:dd:c25:c25:94de:6c48/1282c19:dd:d9:dd:c25:c25:94de:6c48
742c19:dd:d9:dd:c25:c25:94de:6c49/1282c19:dd:d9:dd:c25:c25:94de:6c49
752c19:dd:d9:dd:c25:c25:94de:6c4a/1282c19:dd:d9:dd:c25:c25:94de:6c4a
762c19:dd:d9:dd:c25:c25:94de:6c4b/1282c19:dd:d9:dd:c25:c25:94de:6c4b
772c19:dd:d9:dd:c25:c25:94de:6c4c/1282c19:dd:d9:dd:c25:c25:94de:6c4c
782c19:dd:d9:dd:c25:c25:94de:6c4d/1282c19:dd:d9:dd:c25:c25:94de:6c4d
792c19:dd:d9:dd:c25:c25:94de:6c4e/1282c19:dd:d9:dd:c25:c25:94de:6c4e
802c19:dd:d9:dd:c25:c25:94de:6c4f/1282c19:dd:d9:dd:c25:c25:94de:6c4f
812c19:dd:d9:dd:c25:c25:94de:6c50/1282c19:dd:d9:dd:c25:c25:94de:6c50
822c19:dd:d9:dd:c25:c25:94de:6c51/1282c19:dd:d9:dd:c25:c25:94de:6c51
832c19:dd:d9:dd:c25:c25:94de:6c52/1282c19:dd:d9:dd:c25:c25:94de:6c52
842c19:dd:d9:dd:c25:c25:94de:6c53/1282c19:dd:d9:dd:c25:c25:94de:6c53
852c19:dd:d9:dd:c25:c25:94de:6c54/1282c19:dd:d9:dd:c25:c25:94de:6c54
862c19:dd:d9:dd:c25:c25:94de:6c55/1282c19:dd:d9:dd:c25:c25:94de:6c55
872c19:dd:d9:dd:c25:c25:94de:6c56/1282c19:dd:d9:dd:c25:c25:94de:6c56
882c19:dd:d9:dd:c25:c25:94de:6c57/1282c19:dd:d9:dd:c25:c25:94de:6c57
892c19:dd:d9:dd:c25:c25:94de:6c58/1282c19:dd:d9:dd:c25:c25:94de:6c58
902c19:dd:d9:dd:c25:c25:94de:6c59/1282c19:dd:d9:dd:c25:c25:94de:6c59
912c19:dd:d9:dd:c25:c25:94de:6c5a/1282c19:dd:d9:dd:c25:c25:94de:6c5a
922c19:dd:d9:dd:c25:c25:94de:6c5b/1282c19:dd:d9:dd:c25:c25:94de:6c5b
932c19:dd:d9:dd:c25:c25:94de:6c5c/1282c19:dd:d9:dd:c25:c25:94de:6c5c
942c19:dd:d9:dd:c25:c25:94de:6c5d/1282c19:dd:d9:dd:c25:c25:94de:6c5d
952c19:dd:d9:dd:c25:c25:94de:6c5e/1282c19:dd:d9:dd:c25:c25:94de:6c5e
962c19:dd:d9:dd:c25:c25:94de:6c5f/1282c19:dd:d9:dd:c25:c25:94de:6c5f
972c19:dd:d9:dd:c25:c25:94de:6c60/1282c19:dd:d9:dd:c25:c25:94de:6c60
982c19:dd:d9:dd:c25:c25:94de:6c61/1282c19:dd:d9:dd:c25:c25:94de:6c61
992c19:dd:d9:dd:c25:c25:94de:6c62/1282c19:dd:d9:dd:c25:c25:94de:6c62
1002c19:dd:d9:dd:c25:c25:94de:6c63/1282c19:dd:d9:dd:c25:c25:94de:6c63
1012c19:dd:d9:dd:c25:c25:94de:6c64/1282c19:dd:d9:dd:c25:c25:94de:6c64
1022c19:dd:d9:dd:c25:c25:94de:6c65/1282c19:dd:d9:dd:c25:c25:94de:6c65
1032c19:dd:d9:dd:c25:c25:94de:6c66/1282c19:dd:d9:dd:c25:c25:94de:6c66
1042c19:dd:d9:dd:c25:c25:94de:6c67/1282c19:dd:d9:dd:c25:c25:94de:6c67
1052c19:dd:d9:dd:c25:c25:94de:6c68/1282c19:dd:d9:dd:c25:c25:94de:6c68
1062c19:dd:d9:dd:c25:c25:94de:6c69/1282c19:dd:d9:dd:c25:c25:94de:6c69
1072c19:dd:d9:dd:c25:c25:94de:6c6a/1282c19:dd:d9:dd:c25:c25:94de:6c6a
1082c19:dd:d9:dd:c25:c25:94de:6c6b/1282c19:dd:d9:dd:c25:c25:94de:6c6b
1092c19:dd:d9:dd:c25:c25:94de:6c6c/1282c19:dd:d9:dd:c25:c25:94de:6c6c
1102c19:dd:d9:dd:c25:c25:94de:6c6d/1282c19:dd:d9:dd:c25:c25:94de:6c6d
1112c19:dd:d9:dd:c25:c25:94de:6c6e/1282c19:dd:d9:dd:c25:c25:94de:6c6e
1122c19:dd:d9:dd:c25:c25:94de:6c6f/1282c19:dd:d9:dd:c25:c25:94de:6c6f
1132c19:dd:d9:dd:c25:c25:94de:6c70/1282c19:dd:d9:dd:c25:c25:94de:6c70
1142c19:dd:d9:dd:c25:c25:94de:6c71/1282c19:dd:d9:dd:c25:c25:94de:6c71
1152c19:dd:d9:dd:c25:c25:94de:6c72/1282c19:dd:d9:dd:c25:c25:94de:6c72
1162c19:dd:d9:dd:c25:c25:94de:6c73/1282c19:dd:d9:dd:c25:c25:94de:6c73
1172c19:dd:d9:dd:c25:c25:94de:6c74/1282c19:dd:d9:dd:c25:c25:94de:6c74
1182c19:dd:d9:dd:c25:c25:94de:6c75/1282c19:dd:d9:dd:c25:c25:94de:6c75
1192c19:dd:d9:dd:c25:c25:94de:6c76/1282c19:dd:d9:dd:c25:c25:94de:6c76
1202c19:dd:d9:dd:c25:c25:94de:6c77/1282c19:dd:d9:dd:c25:c25:94de:6c77
1212c19:dd:d9:dd:c25:c25:94de:6c78/1282c19:dd:d9:dd:c25:c25:94de:6c78
1222c19:dd:d9:dd:c25:c25:94de:6c79/1282c19:dd:d9:dd:c25:c25:94de:6c79
1232c19:dd:d9:dd:c25:c25:94de:6c7a/1282c19:dd:d9:dd:c25:c25:94de:6c7a
1242c19:dd:d9:dd:c25:c25:94de:6c7b/1282c19:dd:d9:dd:c25:c25:94de:6c7b
1252c19:dd:d9:dd:c25:c25:94de:6c7c/1282c19:dd:d9:dd:c25:c25:94de:6c7c
1262c19:dd:d9:dd:c25:c25:94de:6c7d/1282c19:dd:d9:dd:c25:c25:94de:6c7d
1272c19:dd:d9:dd:c25:c25:94de:6c7e/1282c19:dd:d9:dd:c25:c25:94de:6c7e
1282c19:dd:d9:dd:c25:c25:94de:6c7f/1282c19:dd:d9:dd:c25:c25:94de:6c7f
1292c19:dd:d9:dd:c25:c25:94de:6c80/1282c19:dd:d9:dd:c25:c25:94de:6c80
1302c19:dd:d9:dd:c25:c25:94de:6c81/1282c19:dd:d9:dd:c25:c25:94de:6c81
1312c19:dd:d9:dd:c25:c25:94de:6c82/1282c19:dd:d9:dd:c25:c25:94de:6c82
1322c19:dd:d9:dd:c25:c25:94de:6c83/1282c19:dd:d9:dd:c25:c25:94de:6c83
1332c19:dd:d9:dd:c25:c25:94de:6c84/1282c19:dd:d9:dd:c25:c25:94de:6c84
1342c19:dd:d9:dd:c25:c25:94de:6c85/1282c19:dd:d9:dd:c25:c25:94de:6c85
1352c19:dd:d9:dd:c25:c25:94de:6c86/1282c19:dd:d9:dd:c25:c25:94de:6c86
1362c19:dd:d9:dd:c25:c25:94de:6c87/1282c19:dd:d9:dd:c25:c25:94de:6c87
1372c19:dd:d9:dd:c25:c25:94de:6c88/1282c19:dd:d9:dd:c25:c25:94de:6c88
1382c19:dd:d9:dd:c25:c25:94de:6c89/1282c19:dd:d9:dd:c25:c25:94de:6c89
1392c19:dd:d9:dd:c25:c25:94de:6c8a/1282c19:dd:d9:dd:c25:c25:94de:6c8a
1402c19:dd:d9:dd:c25:c25:94de:6c8b/1282c19:dd:d9:dd:c25:c25:94de:6c8b
1412c19:dd:d9:dd:c25:c25:94de:6c8c/1282c19:dd:d9:dd:c25:c25:94de:6c8c
1422c19:dd:d9:dd:c25:c25:94de:6c8d/1282c19:dd:d9:dd:c25:c25:94de:6c8d
1432c19:dd:d9:dd:c25:c25:94de:6c8e/1282c19:dd:d9:dd:c25:c25:94de:6c8e
1442c19:dd:d9:dd:c25:c25:94de:6c8f/1282c19:dd:d9:dd:c25:c25:94de:6c8f
1452c19:dd:d9:dd:c25:c25:94de:6c90/1282c19:dd:d9:dd:c25:c25:94de:6c90
1462c19:dd:d9:dd:c25:c25:94de:6c91/1282c19:dd:d9:dd:c25:c25:94de:6c91
1472c19:dd:d9:dd:c25:c25:94de:6c92/1282c19:dd:d9:dd:c25:c25:94de:6c92
1482c19:dd:d9:dd:c25:c25:94de:6c93/1282c19:dd:d9:dd:c25:c25:94de:6c93
1492c19:dd:d9:dd:c25:c25:94de:6c94/1282c19:dd:d9:dd:c25:c25:94de:6c94
1502c19:dd:d9:dd:c25:c25:94de:6c95/1282c19:dd:d9:dd:c25:c25:94de:6c95
1512c19:dd:d9:dd:c25:c25:94de:6c96/1282c19:dd:d9:dd:c25:c25:94de:6c96
1522c19:dd:d9:dd:c25:c25:94de:6c97/1282c19:dd:d9:dd:c25:c25:94de:6c97
1532c19:dd:d9:dd:c25:c25:94de:6c98/1282c19:dd:d9:dd:c25:c25:94de:6c98
1542c19:dd:d9:dd:c25:c25:94de:6c99/1282c19:dd:d9:dd:c25:c25:94de:6c99
1552c19:dd:d9:dd:c25:c25:94de:6c9a/1282c19:dd:d9:dd:c25:c25:94de:6c9a
1562c19:dd:d9:dd:c25:c25:94de:6c9b/1282c19:dd:d9:dd:c25:c25:94de:6c9b
1572c19:dd:d9:dd:c25:c25:94de:6c9c/1282c19:dd:d9:dd:c25:c25:94de:6c9c
1582c19:dd:d9:dd:c25:c25:94de:6c9d/1282c19:dd:d9:dd:c25:c25:94de:6c9d
1592c19:dd:d9:dd:c25:c25:94de:6c9e/1282c19:dd:d9:dd:c25:c25:94de:6c9e
1602c19:dd:d9:dd:c25:c25:94de:6c9f/1282c19:dd:d9:dd:c25:c25:94de:6c9f
1612c19:dd:d9:dd:c25:c25:94de:6ca0/1282c19:dd:d9:dd:c25:c25:94de:6ca0
1622c19:dd:d9:dd:c25:c25:94de:6ca1/1282c19:dd:d9:dd:c25:c25:94de:6ca1
1632c19:dd:d9:dd:c25:c25:94de:6ca2/1282c19:dd:d9:dd:c25:c25:94de:6ca2
1642c19:dd:d9:dd:c25:c25:94de:6ca3/1282c19:dd:d9:dd:c25:c25:94de:6ca3
1652c19:dd:d9:dd:c25:c25:94de:6ca4/1282c19:dd:d9:dd:c25:c25:94de:6ca4
1662c19:dd:d9:dd:c25:c25:94de:6ca5/1282c19:dd:d9:dd:c25:c25:94de:6ca5
1672c19:dd:d9:dd:c25:c25:94de:6ca6/1282c19:dd:d9:dd:c25:c25:94de:6ca6
1682c19:dd:d9:dd:c25:c25:94de:6ca7/1282c19:dd:d9:dd:c25:c25:94de:6ca7
1692c19:dd:d9:dd:c25:c25:94de:6ca8/1282c19:dd:d9:dd:c25:c25:94de:6ca8
1702c19:dd:d9:dd:c25:c25:94de:6ca9/1282c19:dd:d9:dd:c25:c25:94de:6ca9
1712c19:dd:d9:dd:c25:c25:94de:6caa/1282c19:dd:d9:dd:c25:c25:94de:6caa
1722c19:dd:d9:dd:c25:c25:94de:6cab/1282c19:dd:d9:dd:c25:c25:94de:6cab
1732c19:dd:d9:dd:c25:c25:94de:6cac/1282c19:dd:d9:dd:c25:c25:94de:6cac
1742c19:dd:d9:dd:c25:c25:94de:6cad/1282c19:dd:d9:dd:c25:c25:94de:6cad
1752c19:dd:d9:dd:c25:c25:94de:6cae/1282c19:dd:d9:dd:c25:c25:94de:6cae
1762c19:dd:d9:dd:c25:c25:94de:6caf/1282c19:dd:d9:dd:c25:c25:94de:6caf
1772c19:dd:d9:dd:c25:c25:94de:6cb0/1282c19:dd:d9:dd:c25:c25:94de:6cb0
1782c19:dd:d9:dd:c25:c25:94de:6cb1/1282c19:dd:d9:dd:c25:c25:94de:6cb1
1792c19:dd:d9:dd:c25:c25:94de:6cb2/1282c19:dd:d9:dd:c25:c25:94de:6cb2
1802c19:dd:d9:dd:c25:c25:94de:6cb3/1282c19:dd:d9:dd:c25:c25:94de:6cb3
1812c19:dd:d9:dd:c25:c25:94de:6cb4/1282c19:dd:d9:dd:c25:c25:94de:6cb4
1822c19:dd:d9:dd:c25:c25:94de:6cb5/1282c19:dd:d9:dd:c25:c25:94de:6cb5
1832c19:dd:d9:dd:c25:c25:94de:6cb6/1282c19:dd:d9:dd:c25:c25:94de:6cb6
1842c19:dd:d9:dd:c25:c25:94de:6cb7/1282c19:dd:d9:dd:c25:c25:94de:6cb7
1852c19:dd:d9:dd:c25:c25:94de:6cb8/1282c19:dd:d9:dd:c25:c25:94de:6cb8
1862c19:dd:d9:dd:c25:c25:94de:6cb9/1282c19:dd:d9:dd:c25:c25:94de:6cb9
1872c19:dd:d9:dd:c25:c25:94de:6cba/1282c19:dd:d9:dd:c25:c25:94de:6cba
1882c19:dd:d9:dd:c25:c25:94de:6cbb/1282c19:dd:d9:dd:c25:c25:94de:6cbb
1892c19:dd:d9:dd:c25:c25:94de:6cbc/1282c19:dd:d9:dd:c25:c25:94de:6cbc
1902c19:dd:d9:dd:c25:c25:94de:6cbd/1282c19:dd:d9:dd:c25:c25:94de:6cbd
1912c19:dd:d9:dd:c25:c25:94de:6cbe/1282c19:dd:d9:dd:c25:c25:94de:6cbe
1922c19:dd:d9:dd:c25:c25:94de:6cbf/1282c19:dd:d9:dd:c25:c25:94de:6cbf
1932c19:dd:d9:dd:c25:c25:94de:6cc0/1282c19:dd:d9:dd:c25:c25:94de:6cc0
1942c19:dd:d9:dd:c25:c25:94de:6cc1/1282c19:dd:d9:dd:c25:c25:94de:6cc1
1952c19:dd:d9:dd:c25:c25:94de:6cc2/1282c19:dd:d9:dd:c25:c25:94de:6cc2
1962c19:dd:d9:dd:c25:c25:94de:6cc3/1282c19:dd:d9:dd:c25:c25:94de:6cc3
1972c19:dd:d9:dd:c25:c25:94de:6cc4/1282c19:dd:d9:dd:c25:c25:94de:6cc4
1982c19:dd:d9:dd:c25:c25:94de:6cc5/1282c19:dd:d9:dd:c25:c25:94de:6cc5
1992c19:dd:d9:dd:c25:c25:94de:6cc6/1282c19:dd:d9:dd:c25:c25:94de:6cc6
2002c19:dd:d9:dd:c25:c25:94de:6cc7/1282c19:dd:d9:dd:c25:c25:94de:6cc7
2012c19:dd:d9:dd:c25:c25:94de:6cc8/1282c19:dd:d9:dd:c25:c25:94de:6cc8
2022c19:dd:d9:dd:c25:c25:94de:6cc9/1282c19:dd:d9:dd:c25:c25:94de:6cc9
2032c19:dd:d9:dd:c25:c25:94de:6cca/1282c19:dd:d9:dd:c25:c25:94de:6cca
2042c19:dd:d9:dd:c25:c25:94de:6ccb/1282c19:dd:d9:dd:c25:c25:94de:6ccb
2052c19:dd:d9:dd:c25:c25:94de:6ccc/1282c19:dd:d9:dd:c25:c25:94de:6ccc
2062c19:dd:d9:dd:c25:c25:94de:6ccd/1282c19:dd:d9:dd:c25:c25:94de:6ccd
2072c19:dd:d9:dd:c25:c25:94de:6cce/1282c19:dd:d9:dd:c25:c25:94de:6cce
2082c19:dd:d9:dd:c25:c25:94de:6ccf/1282c19:dd:d9:dd:c25:c25:94de:6ccf
2092c19:dd:d9:dd:c25:c25:94de:6cd0/1282c19:dd:d9:dd:c25:c25:94de:6cd0
2102c19:dd:d9:dd:c25:c25:94de:6cd1/1282c19:dd:d9:dd:c25:c25:94de:6cd1
2112c19:dd:d9:dd:c25:c25:94de:6cd2/1282c19:dd:d9:dd:c25:c25:94de:6cd2
2122c19:dd:d9:dd:c25:c25:94de:6cd3/1282c19:dd:d9:dd:c25:c25:94de:6cd3
2132c19:dd:d9:dd:c25:c25:94de:6cd4/1282c19:dd:d9:dd:c25:c25:94de:6cd4
2142c19:dd:d9:dd:c25:c25:94de:6cd5/1282c19:dd:d9:dd:c25:c25:94de:6cd5
2152c19:dd:d9:dd:c25:c25:94de:6cd6/1282c19:dd:d9:dd:c25:c25:94de:6cd6
2162c19:dd:d9:dd:c25:c25:94de:6cd7/1282c19:dd:d9:dd:c25:c25:94de:6cd7
2172c19:dd:d9:dd:c25:c25:94de:6cd8/1282c19:dd:d9:dd:c25:c25:94de:6cd8
2182c19:dd:d9:dd:c25:c25:94de:6cd9/1282c19:dd:d9:dd:c25:c25:94de:6cd9
2192c19:dd:d9:dd:c25:c25:94de:6cda/1282c19:dd:d9:dd:c25:c25:94de:6cda
2202c19:dd:d9:dd:c25:c25:94de:6cdb/1282c19:dd:d9:dd:c25:c25:94de:6cdb
2212c19:dd:d9:dd:c25:c25:94de:6cdc/1282c19:dd:d9:dd:c25:c25:94de:6cdc
2222c19:dd:d9:dd:c25:c25:94de:6cdd/1282c19:dd:d9:dd:c25:c25:94de:6cdd
2232c19:dd:d9:dd:c25:c25:94de:6cde/1282c19:dd:d9:dd:c25:c25:94de:6cde
2242c19:dd:d9:dd:c25:c25:94de:6cdf/1282c19:dd:d9:dd:c25:c25:94de:6cdf
2252c19:dd:d9:dd:c25:c25:94de:6ce0/1282c19:dd:d9:dd:c25:c25:94de:6ce0
2262c19:dd:d9:dd:c25:c25:94de:6ce1/1282c19:dd:d9:dd:c25:c25:94de:6ce1
2272c19:dd:d9:dd:c25:c25:94de:6ce2/1282c19:dd:d9:dd:c25:c25:94de:6ce2
2282c19:dd:d9:dd:c25:c25:94de:6ce3/1282c19:dd:d9:dd:c25:c25:94de:6ce3
2292c19:dd:d9:dd:c25:c25:94de:6ce4/1282c19:dd:d9:dd:c25:c25:94de:6ce4
2302c19:dd:d9:dd:c25:c25:94de:6ce5/1282c19:dd:d9:dd:c25:c25:94de:6ce5
2312c19:dd:d9:dd:c25:c25:94de:6ce6/1282c19:dd:d9:dd:c25:c25:94de:6ce6
2322c19:dd:d9:dd:c25:c25:94de:6ce7/1282c19:dd:d9:dd:c25:c25:94de:6ce7
2332c19:dd:d9:dd:c25:c25:94de:6ce8/1282c19:dd:d9:dd:c25:c25:94de:6ce8
2342c19:dd:d9:dd:c25:c25:94de:6ce9/1282c19:dd:d9:dd:c25:c25:94de:6ce9
2352c19:dd:d9:dd:c25:c25:94de:6cea/1282c19:dd:d9:dd:c25:c25:94de:6cea
2362c19:dd:d9:dd:c25:c25:94de:6ceb/1282c19:dd:d9:dd:c25:c25:94de:6ceb
2372c19:dd:d9:dd:c25:c25:94de:6cec/1282c19:dd:d9:dd:c25:c25:94de:6cec
2382c19:dd:d9:dd:c25:c25:94de:6ced/1282c19:dd:d9:dd:c25:c25:94de:6ced
2392c19:dd:d9:dd:c25:c25:94de:6cee/1282c19:dd:d9:dd:c25:c25:94de:6cee
2402c19:dd:d9:dd:c25:c25:94de:6cef/1282c19:dd:d9:dd:c25:c25:94de:6cef
2412c19:dd:d9:dd:c25:c25:94de:6cf0/1282c19:dd:d9:dd:c25:c25:94de:6cf0
2422c19:dd:d9:dd:c25:c25:94de:6cf1/1282c19:dd:d9:dd:c25:c25:94de:6cf1
2432c19:dd:d9:dd:c25:c25:94de:6cf2/1282c19:dd:d9:dd:c25:c25:94de:6cf2
2442c19:dd:d9:dd:c25:c25:94de:6cf3/1282c19:dd:d9:dd:c25:c25:94de:6cf3
2452c19:dd:d9:dd:c25:c25:94de:6cf4/1282c19:dd:d9:dd:c25:c25:94de:6cf4
2462c19:dd:d9:dd:c25:c25:94de:6cf5/1282c19:dd:d9:dd:c25:c25:94de:6cf5
2472c19:dd:d9:dd:c25:c25:94de:6cf6/1282c19:dd:d9:dd:c25:c25:94de:6cf6
2482c19:dd:d9:dd:c25:c25:94de:6cf7/1282c19:dd:d9:dd:c25:c25:94de:6cf7
2492c19:dd:d9:dd:c25:c25:94de:6cf8/1282c19:dd:d9:dd:c25:c25:94de:6cf8
2502c19:dd:d9:dd:c25:c25:94de:6cf9/1282c19:dd:d9:dd:c25:c25:94de:6cf9
2512c19:dd:d9:dd:c25:c25:94de:6cfa/1282c19:dd:d9:dd:c25:c25:94de:6cfa
2522c19:dd:d9:dd:c25:c25:94de:6cfb/1282c19:dd:d9:dd:c25:c25:94de:6cfb
2532c19:dd:d9:dd:c25:c25:94de:6cfc/1282c19:dd:d9:dd:c25:c25:94de:6cfc
2542c19:dd:d9:dd:c25:c25:94de:6cfd/1282c19:dd:d9:dd:c25:c25:94de:6cfd
2552c19:dd:d9:dd:c25:c25:94de:6cfe/1282c19:dd:d9:dd:c25:c25:94de:6cfe
2562c19:dd:d9:dd:c25:c25:94de:6cff/1282c19:dd:d9:dd:c25:c25:94de:6cff

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.