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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:6a00/120
First address
2c19:dd:d9:dd:c25:c25:94de:6a00
Last address
2c19:dd:d9:dd:c25:c25:94de:6aff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:6a00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
a.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:6a00/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:6a00/1282c19:dd:d9:dd:c25:c25:94de:6a00
22c19:dd:d9:dd:c25:c25:94de:6a01/1282c19:dd:d9:dd:c25:c25:94de:6a01
32c19:dd:d9:dd:c25:c25:94de:6a02/1282c19:dd:d9:dd:c25:c25:94de:6a02
42c19:dd:d9:dd:c25:c25:94de:6a03/1282c19:dd:d9:dd:c25:c25:94de:6a03
52c19:dd:d9:dd:c25:c25:94de:6a04/1282c19:dd:d9:dd:c25:c25:94de:6a04
62c19:dd:d9:dd:c25:c25:94de:6a05/1282c19:dd:d9:dd:c25:c25:94de:6a05
72c19:dd:d9:dd:c25:c25:94de:6a06/1282c19:dd:d9:dd:c25:c25:94de:6a06
82c19:dd:d9:dd:c25:c25:94de:6a07/1282c19:dd:d9:dd:c25:c25:94de:6a07
92c19:dd:d9:dd:c25:c25:94de:6a08/1282c19:dd:d9:dd:c25:c25:94de:6a08
102c19:dd:d9:dd:c25:c25:94de:6a09/1282c19:dd:d9:dd:c25:c25:94de:6a09
112c19:dd:d9:dd:c25:c25:94de:6a0a/1282c19:dd:d9:dd:c25:c25:94de:6a0a
122c19:dd:d9:dd:c25:c25:94de:6a0b/1282c19:dd:d9:dd:c25:c25:94de:6a0b
132c19:dd:d9:dd:c25:c25:94de:6a0c/1282c19:dd:d9:dd:c25:c25:94de:6a0c
142c19:dd:d9:dd:c25:c25:94de:6a0d/1282c19:dd:d9:dd:c25:c25:94de:6a0d
152c19:dd:d9:dd:c25:c25:94de:6a0e/1282c19:dd:d9:dd:c25:c25:94de:6a0e
162c19:dd:d9:dd:c25:c25:94de:6a0f/1282c19:dd:d9:dd:c25:c25:94de:6a0f
172c19:dd:d9:dd:c25:c25:94de:6a10/1282c19:dd:d9:dd:c25:c25:94de:6a10
182c19:dd:d9:dd:c25:c25:94de:6a11/1282c19:dd:d9:dd:c25:c25:94de:6a11
192c19:dd:d9:dd:c25:c25:94de:6a12/1282c19:dd:d9:dd:c25:c25:94de:6a12
202c19:dd:d9:dd:c25:c25:94de:6a13/1282c19:dd:d9:dd:c25:c25:94de:6a13
212c19:dd:d9:dd:c25:c25:94de:6a14/1282c19:dd:d9:dd:c25:c25:94de:6a14
222c19:dd:d9:dd:c25:c25:94de:6a15/1282c19:dd:d9:dd:c25:c25:94de:6a15
232c19:dd:d9:dd:c25:c25:94de:6a16/1282c19:dd:d9:dd:c25:c25:94de:6a16
242c19:dd:d9:dd:c25:c25:94de:6a17/1282c19:dd:d9:dd:c25:c25:94de:6a17
252c19:dd:d9:dd:c25:c25:94de:6a18/1282c19:dd:d9:dd:c25:c25:94de:6a18
262c19:dd:d9:dd:c25:c25:94de:6a19/1282c19:dd:d9:dd:c25:c25:94de:6a19
272c19:dd:d9:dd:c25:c25:94de:6a1a/1282c19:dd:d9:dd:c25:c25:94de:6a1a
282c19:dd:d9:dd:c25:c25:94de:6a1b/1282c19:dd:d9:dd:c25:c25:94de:6a1b
292c19:dd:d9:dd:c25:c25:94de:6a1c/1282c19:dd:d9:dd:c25:c25:94de:6a1c
302c19:dd:d9:dd:c25:c25:94de:6a1d/1282c19:dd:d9:dd:c25:c25:94de:6a1d
312c19:dd:d9:dd:c25:c25:94de:6a1e/1282c19:dd:d9:dd:c25:c25:94de:6a1e
322c19:dd:d9:dd:c25:c25:94de:6a1f/1282c19:dd:d9:dd:c25:c25:94de:6a1f
332c19:dd:d9:dd:c25:c25:94de:6a20/1282c19:dd:d9:dd:c25:c25:94de:6a20
342c19:dd:d9:dd:c25:c25:94de:6a21/1282c19:dd:d9:dd:c25:c25:94de:6a21
352c19:dd:d9:dd:c25:c25:94de:6a22/1282c19:dd:d9:dd:c25:c25:94de:6a22
362c19:dd:d9:dd:c25:c25:94de:6a23/1282c19:dd:d9:dd:c25:c25:94de:6a23
372c19:dd:d9:dd:c25:c25:94de:6a24/1282c19:dd:d9:dd:c25:c25:94de:6a24
382c19:dd:d9:dd:c25:c25:94de:6a25/1282c19:dd:d9:dd:c25:c25:94de:6a25
392c19:dd:d9:dd:c25:c25:94de:6a26/1282c19:dd:d9:dd:c25:c25:94de:6a26
402c19:dd:d9:dd:c25:c25:94de:6a27/1282c19:dd:d9:dd:c25:c25:94de:6a27
412c19:dd:d9:dd:c25:c25:94de:6a28/1282c19:dd:d9:dd:c25:c25:94de:6a28
422c19:dd:d9:dd:c25:c25:94de:6a29/1282c19:dd:d9:dd:c25:c25:94de:6a29
432c19:dd:d9:dd:c25:c25:94de:6a2a/1282c19:dd:d9:dd:c25:c25:94de:6a2a
442c19:dd:d9:dd:c25:c25:94de:6a2b/1282c19:dd:d9:dd:c25:c25:94de:6a2b
452c19:dd:d9:dd:c25:c25:94de:6a2c/1282c19:dd:d9:dd:c25:c25:94de:6a2c
462c19:dd:d9:dd:c25:c25:94de:6a2d/1282c19:dd:d9:dd:c25:c25:94de:6a2d
472c19:dd:d9:dd:c25:c25:94de:6a2e/1282c19:dd:d9:dd:c25:c25:94de:6a2e
482c19:dd:d9:dd:c25:c25:94de:6a2f/1282c19:dd:d9:dd:c25:c25:94de:6a2f
492c19:dd:d9:dd:c25:c25:94de:6a30/1282c19:dd:d9:dd:c25:c25:94de:6a30
502c19:dd:d9:dd:c25:c25:94de:6a31/1282c19:dd:d9:dd:c25:c25:94de:6a31
512c19:dd:d9:dd:c25:c25:94de:6a32/1282c19:dd:d9:dd:c25:c25:94de:6a32
522c19:dd:d9:dd:c25:c25:94de:6a33/1282c19:dd:d9:dd:c25:c25:94de:6a33
532c19:dd:d9:dd:c25:c25:94de:6a34/1282c19:dd:d9:dd:c25:c25:94de:6a34
542c19:dd:d9:dd:c25:c25:94de:6a35/1282c19:dd:d9:dd:c25:c25:94de:6a35
552c19:dd:d9:dd:c25:c25:94de:6a36/1282c19:dd:d9:dd:c25:c25:94de:6a36
562c19:dd:d9:dd:c25:c25:94de:6a37/1282c19:dd:d9:dd:c25:c25:94de:6a37
572c19:dd:d9:dd:c25:c25:94de:6a38/1282c19:dd:d9:dd:c25:c25:94de:6a38
582c19:dd:d9:dd:c25:c25:94de:6a39/1282c19:dd:d9:dd:c25:c25:94de:6a39
592c19:dd:d9:dd:c25:c25:94de:6a3a/1282c19:dd:d9:dd:c25:c25:94de:6a3a
602c19:dd:d9:dd:c25:c25:94de:6a3b/1282c19:dd:d9:dd:c25:c25:94de:6a3b
612c19:dd:d9:dd:c25:c25:94de:6a3c/1282c19:dd:d9:dd:c25:c25:94de:6a3c
622c19:dd:d9:dd:c25:c25:94de:6a3d/1282c19:dd:d9:dd:c25:c25:94de:6a3d
632c19:dd:d9:dd:c25:c25:94de:6a3e/1282c19:dd:d9:dd:c25:c25:94de:6a3e
642c19:dd:d9:dd:c25:c25:94de:6a3f/1282c19:dd:d9:dd:c25:c25:94de:6a3f
652c19:dd:d9:dd:c25:c25:94de:6a40/1282c19:dd:d9:dd:c25:c25:94de:6a40
662c19:dd:d9:dd:c25:c25:94de:6a41/1282c19:dd:d9:dd:c25:c25:94de:6a41
672c19:dd:d9:dd:c25:c25:94de:6a42/1282c19:dd:d9:dd:c25:c25:94de:6a42
682c19:dd:d9:dd:c25:c25:94de:6a43/1282c19:dd:d9:dd:c25:c25:94de:6a43
692c19:dd:d9:dd:c25:c25:94de:6a44/1282c19:dd:d9:dd:c25:c25:94de:6a44
702c19:dd:d9:dd:c25:c25:94de:6a45/1282c19:dd:d9:dd:c25:c25:94de:6a45
712c19:dd:d9:dd:c25:c25:94de:6a46/1282c19:dd:d9:dd:c25:c25:94de:6a46
722c19:dd:d9:dd:c25:c25:94de:6a47/1282c19:dd:d9:dd:c25:c25:94de:6a47
732c19:dd:d9:dd:c25:c25:94de:6a48/1282c19:dd:d9:dd:c25:c25:94de:6a48
742c19:dd:d9:dd:c25:c25:94de:6a49/1282c19:dd:d9:dd:c25:c25:94de:6a49
752c19:dd:d9:dd:c25:c25:94de:6a4a/1282c19:dd:d9:dd:c25:c25:94de:6a4a
762c19:dd:d9:dd:c25:c25:94de:6a4b/1282c19:dd:d9:dd:c25:c25:94de:6a4b
772c19:dd:d9:dd:c25:c25:94de:6a4c/1282c19:dd:d9:dd:c25:c25:94de:6a4c
782c19:dd:d9:dd:c25:c25:94de:6a4d/1282c19:dd:d9:dd:c25:c25:94de:6a4d
792c19:dd:d9:dd:c25:c25:94de:6a4e/1282c19:dd:d9:dd:c25:c25:94de:6a4e
802c19:dd:d9:dd:c25:c25:94de:6a4f/1282c19:dd:d9:dd:c25:c25:94de:6a4f
812c19:dd:d9:dd:c25:c25:94de:6a50/1282c19:dd:d9:dd:c25:c25:94de:6a50
822c19:dd:d9:dd:c25:c25:94de:6a51/1282c19:dd:d9:dd:c25:c25:94de:6a51
832c19:dd:d9:dd:c25:c25:94de:6a52/1282c19:dd:d9:dd:c25:c25:94de:6a52
842c19:dd:d9:dd:c25:c25:94de:6a53/1282c19:dd:d9:dd:c25:c25:94de:6a53
852c19:dd:d9:dd:c25:c25:94de:6a54/1282c19:dd:d9:dd:c25:c25:94de:6a54
862c19:dd:d9:dd:c25:c25:94de:6a55/1282c19:dd:d9:dd:c25:c25:94de:6a55
872c19:dd:d9:dd:c25:c25:94de:6a56/1282c19:dd:d9:dd:c25:c25:94de:6a56
882c19:dd:d9:dd:c25:c25:94de:6a57/1282c19:dd:d9:dd:c25:c25:94de:6a57
892c19:dd:d9:dd:c25:c25:94de:6a58/1282c19:dd:d9:dd:c25:c25:94de:6a58
902c19:dd:d9:dd:c25:c25:94de:6a59/1282c19:dd:d9:dd:c25:c25:94de:6a59
912c19:dd:d9:dd:c25:c25:94de:6a5a/1282c19:dd:d9:dd:c25:c25:94de:6a5a
922c19:dd:d9:dd:c25:c25:94de:6a5b/1282c19:dd:d9:dd:c25:c25:94de:6a5b
932c19:dd:d9:dd:c25:c25:94de:6a5c/1282c19:dd:d9:dd:c25:c25:94de:6a5c
942c19:dd:d9:dd:c25:c25:94de:6a5d/1282c19:dd:d9:dd:c25:c25:94de:6a5d
952c19:dd:d9:dd:c25:c25:94de:6a5e/1282c19:dd:d9:dd:c25:c25:94de:6a5e
962c19:dd:d9:dd:c25:c25:94de:6a5f/1282c19:dd:d9:dd:c25:c25:94de:6a5f
972c19:dd:d9:dd:c25:c25:94de:6a60/1282c19:dd:d9:dd:c25:c25:94de:6a60
982c19:dd:d9:dd:c25:c25:94de:6a61/1282c19:dd:d9:dd:c25:c25:94de:6a61
992c19:dd:d9:dd:c25:c25:94de:6a62/1282c19:dd:d9:dd:c25:c25:94de:6a62
1002c19:dd:d9:dd:c25:c25:94de:6a63/1282c19:dd:d9:dd:c25:c25:94de:6a63
1012c19:dd:d9:dd:c25:c25:94de:6a64/1282c19:dd:d9:dd:c25:c25:94de:6a64
1022c19:dd:d9:dd:c25:c25:94de:6a65/1282c19:dd:d9:dd:c25:c25:94de:6a65
1032c19:dd:d9:dd:c25:c25:94de:6a66/1282c19:dd:d9:dd:c25:c25:94de:6a66
1042c19:dd:d9:dd:c25:c25:94de:6a67/1282c19:dd:d9:dd:c25:c25:94de:6a67
1052c19:dd:d9:dd:c25:c25:94de:6a68/1282c19:dd:d9:dd:c25:c25:94de:6a68
1062c19:dd:d9:dd:c25:c25:94de:6a69/1282c19:dd:d9:dd:c25:c25:94de:6a69
1072c19:dd:d9:dd:c25:c25:94de:6a6a/1282c19:dd:d9:dd:c25:c25:94de:6a6a
1082c19:dd:d9:dd:c25:c25:94de:6a6b/1282c19:dd:d9:dd:c25:c25:94de:6a6b
1092c19:dd:d9:dd:c25:c25:94de:6a6c/1282c19:dd:d9:dd:c25:c25:94de:6a6c
1102c19:dd:d9:dd:c25:c25:94de:6a6d/1282c19:dd:d9:dd:c25:c25:94de:6a6d
1112c19:dd:d9:dd:c25:c25:94de:6a6e/1282c19:dd:d9:dd:c25:c25:94de:6a6e
1122c19:dd:d9:dd:c25:c25:94de:6a6f/1282c19:dd:d9:dd:c25:c25:94de:6a6f
1132c19:dd:d9:dd:c25:c25:94de:6a70/1282c19:dd:d9:dd:c25:c25:94de:6a70
1142c19:dd:d9:dd:c25:c25:94de:6a71/1282c19:dd:d9:dd:c25:c25:94de:6a71
1152c19:dd:d9:dd:c25:c25:94de:6a72/1282c19:dd:d9:dd:c25:c25:94de:6a72
1162c19:dd:d9:dd:c25:c25:94de:6a73/1282c19:dd:d9:dd:c25:c25:94de:6a73
1172c19:dd:d9:dd:c25:c25:94de:6a74/1282c19:dd:d9:dd:c25:c25:94de:6a74
1182c19:dd:d9:dd:c25:c25:94de:6a75/1282c19:dd:d9:dd:c25:c25:94de:6a75
1192c19:dd:d9:dd:c25:c25:94de:6a76/1282c19:dd:d9:dd:c25:c25:94de:6a76
1202c19:dd:d9:dd:c25:c25:94de:6a77/1282c19:dd:d9:dd:c25:c25:94de:6a77
1212c19:dd:d9:dd:c25:c25:94de:6a78/1282c19:dd:d9:dd:c25:c25:94de:6a78
1222c19:dd:d9:dd:c25:c25:94de:6a79/1282c19:dd:d9:dd:c25:c25:94de:6a79
1232c19:dd:d9:dd:c25:c25:94de:6a7a/1282c19:dd:d9:dd:c25:c25:94de:6a7a
1242c19:dd:d9:dd:c25:c25:94de:6a7b/1282c19:dd:d9:dd:c25:c25:94de:6a7b
1252c19:dd:d9:dd:c25:c25:94de:6a7c/1282c19:dd:d9:dd:c25:c25:94de:6a7c
1262c19:dd:d9:dd:c25:c25:94de:6a7d/1282c19:dd:d9:dd:c25:c25:94de:6a7d
1272c19:dd:d9:dd:c25:c25:94de:6a7e/1282c19:dd:d9:dd:c25:c25:94de:6a7e
1282c19:dd:d9:dd:c25:c25:94de:6a7f/1282c19:dd:d9:dd:c25:c25:94de:6a7f
1292c19:dd:d9:dd:c25:c25:94de:6a80/1282c19:dd:d9:dd:c25:c25:94de:6a80
1302c19:dd:d9:dd:c25:c25:94de:6a81/1282c19:dd:d9:dd:c25:c25:94de:6a81
1312c19:dd:d9:dd:c25:c25:94de:6a82/1282c19:dd:d9:dd:c25:c25:94de:6a82
1322c19:dd:d9:dd:c25:c25:94de:6a83/1282c19:dd:d9:dd:c25:c25:94de:6a83
1332c19:dd:d9:dd:c25:c25:94de:6a84/1282c19:dd:d9:dd:c25:c25:94de:6a84
1342c19:dd:d9:dd:c25:c25:94de:6a85/1282c19:dd:d9:dd:c25:c25:94de:6a85
1352c19:dd:d9:dd:c25:c25:94de:6a86/1282c19:dd:d9:dd:c25:c25:94de:6a86
1362c19:dd:d9:dd:c25:c25:94de:6a87/1282c19:dd:d9:dd:c25:c25:94de:6a87
1372c19:dd:d9:dd:c25:c25:94de:6a88/1282c19:dd:d9:dd:c25:c25:94de:6a88
1382c19:dd:d9:dd:c25:c25:94de:6a89/1282c19:dd:d9:dd:c25:c25:94de:6a89
1392c19:dd:d9:dd:c25:c25:94de:6a8a/1282c19:dd:d9:dd:c25:c25:94de:6a8a
1402c19:dd:d9:dd:c25:c25:94de:6a8b/1282c19:dd:d9:dd:c25:c25:94de:6a8b
1412c19:dd:d9:dd:c25:c25:94de:6a8c/1282c19:dd:d9:dd:c25:c25:94de:6a8c
1422c19:dd:d9:dd:c25:c25:94de:6a8d/1282c19:dd:d9:dd:c25:c25:94de:6a8d
1432c19:dd:d9:dd:c25:c25:94de:6a8e/1282c19:dd:d9:dd:c25:c25:94de:6a8e
1442c19:dd:d9:dd:c25:c25:94de:6a8f/1282c19:dd:d9:dd:c25:c25:94de:6a8f
1452c19:dd:d9:dd:c25:c25:94de:6a90/1282c19:dd:d9:dd:c25:c25:94de:6a90
1462c19:dd:d9:dd:c25:c25:94de:6a91/1282c19:dd:d9:dd:c25:c25:94de:6a91
1472c19:dd:d9:dd:c25:c25:94de:6a92/1282c19:dd:d9:dd:c25:c25:94de:6a92
1482c19:dd:d9:dd:c25:c25:94de:6a93/1282c19:dd:d9:dd:c25:c25:94de:6a93
1492c19:dd:d9:dd:c25:c25:94de:6a94/1282c19:dd:d9:dd:c25:c25:94de:6a94
1502c19:dd:d9:dd:c25:c25:94de:6a95/1282c19:dd:d9:dd:c25:c25:94de:6a95
1512c19:dd:d9:dd:c25:c25:94de:6a96/1282c19:dd:d9:dd:c25:c25:94de:6a96
1522c19:dd:d9:dd:c25:c25:94de:6a97/1282c19:dd:d9:dd:c25:c25:94de:6a97
1532c19:dd:d9:dd:c25:c25:94de:6a98/1282c19:dd:d9:dd:c25:c25:94de:6a98
1542c19:dd:d9:dd:c25:c25:94de:6a99/1282c19:dd:d9:dd:c25:c25:94de:6a99
1552c19:dd:d9:dd:c25:c25:94de:6a9a/1282c19:dd:d9:dd:c25:c25:94de:6a9a
1562c19:dd:d9:dd:c25:c25:94de:6a9b/1282c19:dd:d9:dd:c25:c25:94de:6a9b
1572c19:dd:d9:dd:c25:c25:94de:6a9c/1282c19:dd:d9:dd:c25:c25:94de:6a9c
1582c19:dd:d9:dd:c25:c25:94de:6a9d/1282c19:dd:d9:dd:c25:c25:94de:6a9d
1592c19:dd:d9:dd:c25:c25:94de:6a9e/1282c19:dd:d9:dd:c25:c25:94de:6a9e
1602c19:dd:d9:dd:c25:c25:94de:6a9f/1282c19:dd:d9:dd:c25:c25:94de:6a9f
1612c19:dd:d9:dd:c25:c25:94de:6aa0/1282c19:dd:d9:dd:c25:c25:94de:6aa0
1622c19:dd:d9:dd:c25:c25:94de:6aa1/1282c19:dd:d9:dd:c25:c25:94de:6aa1
1632c19:dd:d9:dd:c25:c25:94de:6aa2/1282c19:dd:d9:dd:c25:c25:94de:6aa2
1642c19:dd:d9:dd:c25:c25:94de:6aa3/1282c19:dd:d9:dd:c25:c25:94de:6aa3
1652c19:dd:d9:dd:c25:c25:94de:6aa4/1282c19:dd:d9:dd:c25:c25:94de:6aa4
1662c19:dd:d9:dd:c25:c25:94de:6aa5/1282c19:dd:d9:dd:c25:c25:94de:6aa5
1672c19:dd:d9:dd:c25:c25:94de:6aa6/1282c19:dd:d9:dd:c25:c25:94de:6aa6
1682c19:dd:d9:dd:c25:c25:94de:6aa7/1282c19:dd:d9:dd:c25:c25:94de:6aa7
1692c19:dd:d9:dd:c25:c25:94de:6aa8/1282c19:dd:d9:dd:c25:c25:94de:6aa8
1702c19:dd:d9:dd:c25:c25:94de:6aa9/1282c19:dd:d9:dd:c25:c25:94de:6aa9
1712c19:dd:d9:dd:c25:c25:94de:6aaa/1282c19:dd:d9:dd:c25:c25:94de:6aaa
1722c19:dd:d9:dd:c25:c25:94de:6aab/1282c19:dd:d9:dd:c25:c25:94de:6aab
1732c19:dd:d9:dd:c25:c25:94de:6aac/1282c19:dd:d9:dd:c25:c25:94de:6aac
1742c19:dd:d9:dd:c25:c25:94de:6aad/1282c19:dd:d9:dd:c25:c25:94de:6aad
1752c19:dd:d9:dd:c25:c25:94de:6aae/1282c19:dd:d9:dd:c25:c25:94de:6aae
1762c19:dd:d9:dd:c25:c25:94de:6aaf/1282c19:dd:d9:dd:c25:c25:94de:6aaf
1772c19:dd:d9:dd:c25:c25:94de:6ab0/1282c19:dd:d9:dd:c25:c25:94de:6ab0
1782c19:dd:d9:dd:c25:c25:94de:6ab1/1282c19:dd:d9:dd:c25:c25:94de:6ab1
1792c19:dd:d9:dd:c25:c25:94de:6ab2/1282c19:dd:d9:dd:c25:c25:94de:6ab2
1802c19:dd:d9:dd:c25:c25:94de:6ab3/1282c19:dd:d9:dd:c25:c25:94de:6ab3
1812c19:dd:d9:dd:c25:c25:94de:6ab4/1282c19:dd:d9:dd:c25:c25:94de:6ab4
1822c19:dd:d9:dd:c25:c25:94de:6ab5/1282c19:dd:d9:dd:c25:c25:94de:6ab5
1832c19:dd:d9:dd:c25:c25:94de:6ab6/1282c19:dd:d9:dd:c25:c25:94de:6ab6
1842c19:dd:d9:dd:c25:c25:94de:6ab7/1282c19:dd:d9:dd:c25:c25:94de:6ab7
1852c19:dd:d9:dd:c25:c25:94de:6ab8/1282c19:dd:d9:dd:c25:c25:94de:6ab8
1862c19:dd:d9:dd:c25:c25:94de:6ab9/1282c19:dd:d9:dd:c25:c25:94de:6ab9
1872c19:dd:d9:dd:c25:c25:94de:6aba/1282c19:dd:d9:dd:c25:c25:94de:6aba
1882c19:dd:d9:dd:c25:c25:94de:6abb/1282c19:dd:d9:dd:c25:c25:94de:6abb
1892c19:dd:d9:dd:c25:c25:94de:6abc/1282c19:dd:d9:dd:c25:c25:94de:6abc
1902c19:dd:d9:dd:c25:c25:94de:6abd/1282c19:dd:d9:dd:c25:c25:94de:6abd
1912c19:dd:d9:dd:c25:c25:94de:6abe/1282c19:dd:d9:dd:c25:c25:94de:6abe
1922c19:dd:d9:dd:c25:c25:94de:6abf/1282c19:dd:d9:dd:c25:c25:94de:6abf
1932c19:dd:d9:dd:c25:c25:94de:6ac0/1282c19:dd:d9:dd:c25:c25:94de:6ac0
1942c19:dd:d9:dd:c25:c25:94de:6ac1/1282c19:dd:d9:dd:c25:c25:94de:6ac1
1952c19:dd:d9:dd:c25:c25:94de:6ac2/1282c19:dd:d9:dd:c25:c25:94de:6ac2
1962c19:dd:d9:dd:c25:c25:94de:6ac3/1282c19:dd:d9:dd:c25:c25:94de:6ac3
1972c19:dd:d9:dd:c25:c25:94de:6ac4/1282c19:dd:d9:dd:c25:c25:94de:6ac4
1982c19:dd:d9:dd:c25:c25:94de:6ac5/1282c19:dd:d9:dd:c25:c25:94de:6ac5
1992c19:dd:d9:dd:c25:c25:94de:6ac6/1282c19:dd:d9:dd:c25:c25:94de:6ac6
2002c19:dd:d9:dd:c25:c25:94de:6ac7/1282c19:dd:d9:dd:c25:c25:94de:6ac7
2012c19:dd:d9:dd:c25:c25:94de:6ac8/1282c19:dd:d9:dd:c25:c25:94de:6ac8
2022c19:dd:d9:dd:c25:c25:94de:6ac9/1282c19:dd:d9:dd:c25:c25:94de:6ac9
2032c19:dd:d9:dd:c25:c25:94de:6aca/1282c19:dd:d9:dd:c25:c25:94de:6aca
2042c19:dd:d9:dd:c25:c25:94de:6acb/1282c19:dd:d9:dd:c25:c25:94de:6acb
2052c19:dd:d9:dd:c25:c25:94de:6acc/1282c19:dd:d9:dd:c25:c25:94de:6acc
2062c19:dd:d9:dd:c25:c25:94de:6acd/1282c19:dd:d9:dd:c25:c25:94de:6acd
2072c19:dd:d9:dd:c25:c25:94de:6ace/1282c19:dd:d9:dd:c25:c25:94de:6ace
2082c19:dd:d9:dd:c25:c25:94de:6acf/1282c19:dd:d9:dd:c25:c25:94de:6acf
2092c19:dd:d9:dd:c25:c25:94de:6ad0/1282c19:dd:d9:dd:c25:c25:94de:6ad0
2102c19:dd:d9:dd:c25:c25:94de:6ad1/1282c19:dd:d9:dd:c25:c25:94de:6ad1
2112c19:dd:d9:dd:c25:c25:94de:6ad2/1282c19:dd:d9:dd:c25:c25:94de:6ad2
2122c19:dd:d9:dd:c25:c25:94de:6ad3/1282c19:dd:d9:dd:c25:c25:94de:6ad3
2132c19:dd:d9:dd:c25:c25:94de:6ad4/1282c19:dd:d9:dd:c25:c25:94de:6ad4
2142c19:dd:d9:dd:c25:c25:94de:6ad5/1282c19:dd:d9:dd:c25:c25:94de:6ad5
2152c19:dd:d9:dd:c25:c25:94de:6ad6/1282c19:dd:d9:dd:c25:c25:94de:6ad6
2162c19:dd:d9:dd:c25:c25:94de:6ad7/1282c19:dd:d9:dd:c25:c25:94de:6ad7
2172c19:dd:d9:dd:c25:c25:94de:6ad8/1282c19:dd:d9:dd:c25:c25:94de:6ad8
2182c19:dd:d9:dd:c25:c25:94de:6ad9/1282c19:dd:d9:dd:c25:c25:94de:6ad9
2192c19:dd:d9:dd:c25:c25:94de:6ada/1282c19:dd:d9:dd:c25:c25:94de:6ada
2202c19:dd:d9:dd:c25:c25:94de:6adb/1282c19:dd:d9:dd:c25:c25:94de:6adb
2212c19:dd:d9:dd:c25:c25:94de:6adc/1282c19:dd:d9:dd:c25:c25:94de:6adc
2222c19:dd:d9:dd:c25:c25:94de:6add/1282c19:dd:d9:dd:c25:c25:94de:6add
2232c19:dd:d9:dd:c25:c25:94de:6ade/1282c19:dd:d9:dd:c25:c25:94de:6ade
2242c19:dd:d9:dd:c25:c25:94de:6adf/1282c19:dd:d9:dd:c25:c25:94de:6adf
2252c19:dd:d9:dd:c25:c25:94de:6ae0/1282c19:dd:d9:dd:c25:c25:94de:6ae0
2262c19:dd:d9:dd:c25:c25:94de:6ae1/1282c19:dd:d9:dd:c25:c25:94de:6ae1
2272c19:dd:d9:dd:c25:c25:94de:6ae2/1282c19:dd:d9:dd:c25:c25:94de:6ae2
2282c19:dd:d9:dd:c25:c25:94de:6ae3/1282c19:dd:d9:dd:c25:c25:94de:6ae3
2292c19:dd:d9:dd:c25:c25:94de:6ae4/1282c19:dd:d9:dd:c25:c25:94de:6ae4
2302c19:dd:d9:dd:c25:c25:94de:6ae5/1282c19:dd:d9:dd:c25:c25:94de:6ae5
2312c19:dd:d9:dd:c25:c25:94de:6ae6/1282c19:dd:d9:dd:c25:c25:94de:6ae6
2322c19:dd:d9:dd:c25:c25:94de:6ae7/1282c19:dd:d9:dd:c25:c25:94de:6ae7
2332c19:dd:d9:dd:c25:c25:94de:6ae8/1282c19:dd:d9:dd:c25:c25:94de:6ae8
2342c19:dd:d9:dd:c25:c25:94de:6ae9/1282c19:dd:d9:dd:c25:c25:94de:6ae9
2352c19:dd:d9:dd:c25:c25:94de:6aea/1282c19:dd:d9:dd:c25:c25:94de:6aea
2362c19:dd:d9:dd:c25:c25:94de:6aeb/1282c19:dd:d9:dd:c25:c25:94de:6aeb
2372c19:dd:d9:dd:c25:c25:94de:6aec/1282c19:dd:d9:dd:c25:c25:94de:6aec
2382c19:dd:d9:dd:c25:c25:94de:6aed/1282c19:dd:d9:dd:c25:c25:94de:6aed
2392c19:dd:d9:dd:c25:c25:94de:6aee/1282c19:dd:d9:dd:c25:c25:94de:6aee
2402c19:dd:d9:dd:c25:c25:94de:6aef/1282c19:dd:d9:dd:c25:c25:94de:6aef
2412c19:dd:d9:dd:c25:c25:94de:6af0/1282c19:dd:d9:dd:c25:c25:94de:6af0
2422c19:dd:d9:dd:c25:c25:94de:6af1/1282c19:dd:d9:dd:c25:c25:94de:6af1
2432c19:dd:d9:dd:c25:c25:94de:6af2/1282c19:dd:d9:dd:c25:c25:94de:6af2
2442c19:dd:d9:dd:c25:c25:94de:6af3/1282c19:dd:d9:dd:c25:c25:94de:6af3
2452c19:dd:d9:dd:c25:c25:94de:6af4/1282c19:dd:d9:dd:c25:c25:94de:6af4
2462c19:dd:d9:dd:c25:c25:94de:6af5/1282c19:dd:d9:dd:c25:c25:94de:6af5
2472c19:dd:d9:dd:c25:c25:94de:6af6/1282c19:dd:d9:dd:c25:c25:94de:6af6
2482c19:dd:d9:dd:c25:c25:94de:6af7/1282c19:dd:d9:dd:c25:c25:94de:6af7
2492c19:dd:d9:dd:c25:c25:94de:6af8/1282c19:dd:d9:dd:c25:c25:94de:6af8
2502c19:dd:d9:dd:c25:c25:94de:6af9/1282c19:dd:d9:dd:c25:c25:94de:6af9
2512c19:dd:d9:dd:c25:c25:94de:6afa/1282c19:dd:d9:dd:c25:c25:94de:6afa
2522c19:dd:d9:dd:c25:c25:94de:6afb/1282c19:dd:d9:dd:c25:c25:94de:6afb
2532c19:dd:d9:dd:c25:c25:94de:6afc/1282c19:dd:d9:dd:c25:c25:94de:6afc
2542c19:dd:d9:dd:c25:c25:94de:6afd/1282c19:dd:d9:dd:c25:c25:94de:6afd
2552c19:dd:d9:dd:c25:c25:94de:6afe/1282c19:dd:d9:dd:c25:c25:94de:6afe
2562c19:dd:d9:dd:c25:c25:94de:6aff/1282c19:dd:d9:dd:c25:c25:94de:6aff

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.