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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:c25:c25:dd:dd:dd:2a00/119
First address
2c19:dd:c25:c25:dd:dd:dd:2a00
Last address
2c19:dd:c25:c25:dd:dd:dd:2bff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:0c25:00dd:00dd:00dd:2a00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
a.2.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
b.2.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.0.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/127
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:c25:c25:dd:dd:dd:2a00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:c25:c25:dd:dd:dd:2a00/1272c19:dd:c25:c25:dd:dd:dd:2a01
22c19:dd:c25:c25:dd:dd:dd:2a02/1272c19:dd:c25:c25:dd:dd:dd:2a03
32c19:dd:c25:c25:dd:dd:dd:2a04/1272c19:dd:c25:c25:dd:dd:dd:2a05
42c19:dd:c25:c25:dd:dd:dd:2a06/1272c19:dd:c25:c25:dd:dd:dd:2a07
52c19:dd:c25:c25:dd:dd:dd:2a08/1272c19:dd:c25:c25:dd:dd:dd:2a09
62c19:dd:c25:c25:dd:dd:dd:2a0a/1272c19:dd:c25:c25:dd:dd:dd:2a0b
72c19:dd:c25:c25:dd:dd:dd:2a0c/1272c19:dd:c25:c25:dd:dd:dd:2a0d
82c19:dd:c25:c25:dd:dd:dd:2a0e/1272c19:dd:c25:c25:dd:dd:dd:2a0f
92c19:dd:c25:c25:dd:dd:dd:2a10/1272c19:dd:c25:c25:dd:dd:dd:2a11
102c19:dd:c25:c25:dd:dd:dd:2a12/1272c19:dd:c25:c25:dd:dd:dd:2a13
112c19:dd:c25:c25:dd:dd:dd:2a14/1272c19:dd:c25:c25:dd:dd:dd:2a15
122c19:dd:c25:c25:dd:dd:dd:2a16/1272c19:dd:c25:c25:dd:dd:dd:2a17
132c19:dd:c25:c25:dd:dd:dd:2a18/1272c19:dd:c25:c25:dd:dd:dd:2a19
142c19:dd:c25:c25:dd:dd:dd:2a1a/1272c19:dd:c25:c25:dd:dd:dd:2a1b
152c19:dd:c25:c25:dd:dd:dd:2a1c/1272c19:dd:c25:c25:dd:dd:dd:2a1d
162c19:dd:c25:c25:dd:dd:dd:2a1e/1272c19:dd:c25:c25:dd:dd:dd:2a1f
172c19:dd:c25:c25:dd:dd:dd:2a20/1272c19:dd:c25:c25:dd:dd:dd:2a21
182c19:dd:c25:c25:dd:dd:dd:2a22/1272c19:dd:c25:c25:dd:dd:dd:2a23
192c19:dd:c25:c25:dd:dd:dd:2a24/1272c19:dd:c25:c25:dd:dd:dd:2a25
202c19:dd:c25:c25:dd:dd:dd:2a26/1272c19:dd:c25:c25:dd:dd:dd:2a27
212c19:dd:c25:c25:dd:dd:dd:2a28/1272c19:dd:c25:c25:dd:dd:dd:2a29
222c19:dd:c25:c25:dd:dd:dd:2a2a/1272c19:dd:c25:c25:dd:dd:dd:2a2b
232c19:dd:c25:c25:dd:dd:dd:2a2c/1272c19:dd:c25:c25:dd:dd:dd:2a2d
242c19:dd:c25:c25:dd:dd:dd:2a2e/1272c19:dd:c25:c25:dd:dd:dd:2a2f
252c19:dd:c25:c25:dd:dd:dd:2a30/1272c19:dd:c25:c25:dd:dd:dd:2a31
262c19:dd:c25:c25:dd:dd:dd:2a32/1272c19:dd:c25:c25:dd:dd:dd:2a33
272c19:dd:c25:c25:dd:dd:dd:2a34/1272c19:dd:c25:c25:dd:dd:dd:2a35
282c19:dd:c25:c25:dd:dd:dd:2a36/1272c19:dd:c25:c25:dd:dd:dd:2a37
292c19:dd:c25:c25:dd:dd:dd:2a38/1272c19:dd:c25:c25:dd:dd:dd:2a39
302c19:dd:c25:c25:dd:dd:dd:2a3a/1272c19:dd:c25:c25:dd:dd:dd:2a3b
312c19:dd:c25:c25:dd:dd:dd:2a3c/1272c19:dd:c25:c25:dd:dd:dd:2a3d
322c19:dd:c25:c25:dd:dd:dd:2a3e/1272c19:dd:c25:c25:dd:dd:dd:2a3f
332c19:dd:c25:c25:dd:dd:dd:2a40/1272c19:dd:c25:c25:dd:dd:dd:2a41
342c19:dd:c25:c25:dd:dd:dd:2a42/1272c19:dd:c25:c25:dd:dd:dd:2a43
352c19:dd:c25:c25:dd:dd:dd:2a44/1272c19:dd:c25:c25:dd:dd:dd:2a45
362c19:dd:c25:c25:dd:dd:dd:2a46/1272c19:dd:c25:c25:dd:dd:dd:2a47
372c19:dd:c25:c25:dd:dd:dd:2a48/1272c19:dd:c25:c25:dd:dd:dd:2a49
382c19:dd:c25:c25:dd:dd:dd:2a4a/1272c19:dd:c25:c25:dd:dd:dd:2a4b
392c19:dd:c25:c25:dd:dd:dd:2a4c/1272c19:dd:c25:c25:dd:dd:dd:2a4d
402c19:dd:c25:c25:dd:dd:dd:2a4e/1272c19:dd:c25:c25:dd:dd:dd:2a4f
412c19:dd:c25:c25:dd:dd:dd:2a50/1272c19:dd:c25:c25:dd:dd:dd:2a51
422c19:dd:c25:c25:dd:dd:dd:2a52/1272c19:dd:c25:c25:dd:dd:dd:2a53
432c19:dd:c25:c25:dd:dd:dd:2a54/1272c19:dd:c25:c25:dd:dd:dd:2a55
442c19:dd:c25:c25:dd:dd:dd:2a56/1272c19:dd:c25:c25:dd:dd:dd:2a57
452c19:dd:c25:c25:dd:dd:dd:2a58/1272c19:dd:c25:c25:dd:dd:dd:2a59
462c19:dd:c25:c25:dd:dd:dd:2a5a/1272c19:dd:c25:c25:dd:dd:dd:2a5b
472c19:dd:c25:c25:dd:dd:dd:2a5c/1272c19:dd:c25:c25:dd:dd:dd:2a5d
482c19:dd:c25:c25:dd:dd:dd:2a5e/1272c19:dd:c25:c25:dd:dd:dd:2a5f
492c19:dd:c25:c25:dd:dd:dd:2a60/1272c19:dd:c25:c25:dd:dd:dd:2a61
502c19:dd:c25:c25:dd:dd:dd:2a62/1272c19:dd:c25:c25:dd:dd:dd:2a63
512c19:dd:c25:c25:dd:dd:dd:2a64/1272c19:dd:c25:c25:dd:dd:dd:2a65
522c19:dd:c25:c25:dd:dd:dd:2a66/1272c19:dd:c25:c25:dd:dd:dd:2a67
532c19:dd:c25:c25:dd:dd:dd:2a68/1272c19:dd:c25:c25:dd:dd:dd:2a69
542c19:dd:c25:c25:dd:dd:dd:2a6a/1272c19:dd:c25:c25:dd:dd:dd:2a6b
552c19:dd:c25:c25:dd:dd:dd:2a6c/1272c19:dd:c25:c25:dd:dd:dd:2a6d
562c19:dd:c25:c25:dd:dd:dd:2a6e/1272c19:dd:c25:c25:dd:dd:dd:2a6f
572c19:dd:c25:c25:dd:dd:dd:2a70/1272c19:dd:c25:c25:dd:dd:dd:2a71
582c19:dd:c25:c25:dd:dd:dd:2a72/1272c19:dd:c25:c25:dd:dd:dd:2a73
592c19:dd:c25:c25:dd:dd:dd:2a74/1272c19:dd:c25:c25:dd:dd:dd:2a75
602c19:dd:c25:c25:dd:dd:dd:2a76/1272c19:dd:c25:c25:dd:dd:dd:2a77
612c19:dd:c25:c25:dd:dd:dd:2a78/1272c19:dd:c25:c25:dd:dd:dd:2a79
622c19:dd:c25:c25:dd:dd:dd:2a7a/1272c19:dd:c25:c25:dd:dd:dd:2a7b
632c19:dd:c25:c25:dd:dd:dd:2a7c/1272c19:dd:c25:c25:dd:dd:dd:2a7d
642c19:dd:c25:c25:dd:dd:dd:2a7e/1272c19:dd:c25:c25:dd:dd:dd:2a7f
652c19:dd:c25:c25:dd:dd:dd:2a80/1272c19:dd:c25:c25:dd:dd:dd:2a81
662c19:dd:c25:c25:dd:dd:dd:2a82/1272c19:dd:c25:c25:dd:dd:dd:2a83
672c19:dd:c25:c25:dd:dd:dd:2a84/1272c19:dd:c25:c25:dd:dd:dd:2a85
682c19:dd:c25:c25:dd:dd:dd:2a86/1272c19:dd:c25:c25:dd:dd:dd:2a87
692c19:dd:c25:c25:dd:dd:dd:2a88/1272c19:dd:c25:c25:dd:dd:dd:2a89
702c19:dd:c25:c25:dd:dd:dd:2a8a/1272c19:dd:c25:c25:dd:dd:dd:2a8b
712c19:dd:c25:c25:dd:dd:dd:2a8c/1272c19:dd:c25:c25:dd:dd:dd:2a8d
722c19:dd:c25:c25:dd:dd:dd:2a8e/1272c19:dd:c25:c25:dd:dd:dd:2a8f
732c19:dd:c25:c25:dd:dd:dd:2a90/1272c19:dd:c25:c25:dd:dd:dd:2a91
742c19:dd:c25:c25:dd:dd:dd:2a92/1272c19:dd:c25:c25:dd:dd:dd:2a93
752c19:dd:c25:c25:dd:dd:dd:2a94/1272c19:dd:c25:c25:dd:dd:dd:2a95
762c19:dd:c25:c25:dd:dd:dd:2a96/1272c19:dd:c25:c25:dd:dd:dd:2a97
772c19:dd:c25:c25:dd:dd:dd:2a98/1272c19:dd:c25:c25:dd:dd:dd:2a99
782c19:dd:c25:c25:dd:dd:dd:2a9a/1272c19:dd:c25:c25:dd:dd:dd:2a9b
792c19:dd:c25:c25:dd:dd:dd:2a9c/1272c19:dd:c25:c25:dd:dd:dd:2a9d
802c19:dd:c25:c25:dd:dd:dd:2a9e/1272c19:dd:c25:c25:dd:dd:dd:2a9f
812c19:dd:c25:c25:dd:dd:dd:2aa0/1272c19:dd:c25:c25:dd:dd:dd:2aa1
822c19:dd:c25:c25:dd:dd:dd:2aa2/1272c19:dd:c25:c25:dd:dd:dd:2aa3
832c19:dd:c25:c25:dd:dd:dd:2aa4/1272c19:dd:c25:c25:dd:dd:dd:2aa5
842c19:dd:c25:c25:dd:dd:dd:2aa6/1272c19:dd:c25:c25:dd:dd:dd:2aa7
852c19:dd:c25:c25:dd:dd:dd:2aa8/1272c19:dd:c25:c25:dd:dd:dd:2aa9
862c19:dd:c25:c25:dd:dd:dd:2aaa/1272c19:dd:c25:c25:dd:dd:dd:2aab
872c19:dd:c25:c25:dd:dd:dd:2aac/1272c19:dd:c25:c25:dd:dd:dd:2aad
882c19:dd:c25:c25:dd:dd:dd:2aae/1272c19:dd:c25:c25:dd:dd:dd:2aaf
892c19:dd:c25:c25:dd:dd:dd:2ab0/1272c19:dd:c25:c25:dd:dd:dd:2ab1
902c19:dd:c25:c25:dd:dd:dd:2ab2/1272c19:dd:c25:c25:dd:dd:dd:2ab3
912c19:dd:c25:c25:dd:dd:dd:2ab4/1272c19:dd:c25:c25:dd:dd:dd:2ab5
922c19:dd:c25:c25:dd:dd:dd:2ab6/1272c19:dd:c25:c25:dd:dd:dd:2ab7
932c19:dd:c25:c25:dd:dd:dd:2ab8/1272c19:dd:c25:c25:dd:dd:dd:2ab9
942c19:dd:c25:c25:dd:dd:dd:2aba/1272c19:dd:c25:c25:dd:dd:dd:2abb
952c19:dd:c25:c25:dd:dd:dd:2abc/1272c19:dd:c25:c25:dd:dd:dd:2abd
962c19:dd:c25:c25:dd:dd:dd:2abe/1272c19:dd:c25:c25:dd:dd:dd:2abf
972c19:dd:c25:c25:dd:dd:dd:2ac0/1272c19:dd:c25:c25:dd:dd:dd:2ac1
982c19:dd:c25:c25:dd:dd:dd:2ac2/1272c19:dd:c25:c25:dd:dd:dd:2ac3
992c19:dd:c25:c25:dd:dd:dd:2ac4/1272c19:dd:c25:c25:dd:dd:dd:2ac5
1002c19:dd:c25:c25:dd:dd:dd:2ac6/1272c19:dd:c25:c25:dd:dd:dd:2ac7
1012c19:dd:c25:c25:dd:dd:dd:2ac8/1272c19:dd:c25:c25:dd:dd:dd:2ac9
1022c19:dd:c25:c25:dd:dd:dd:2aca/1272c19:dd:c25:c25:dd:dd:dd:2acb
1032c19:dd:c25:c25:dd:dd:dd:2acc/1272c19:dd:c25:c25:dd:dd:dd:2acd
1042c19:dd:c25:c25:dd:dd:dd:2ace/1272c19:dd:c25:c25:dd:dd:dd:2acf
1052c19:dd:c25:c25:dd:dd:dd:2ad0/1272c19:dd:c25:c25:dd:dd:dd:2ad1
1062c19:dd:c25:c25:dd:dd:dd:2ad2/1272c19:dd:c25:c25:dd:dd:dd:2ad3
1072c19:dd:c25:c25:dd:dd:dd:2ad4/1272c19:dd:c25:c25:dd:dd:dd:2ad5
1082c19:dd:c25:c25:dd:dd:dd:2ad6/1272c19:dd:c25:c25:dd:dd:dd:2ad7
1092c19:dd:c25:c25:dd:dd:dd:2ad8/1272c19:dd:c25:c25:dd:dd:dd:2ad9
1102c19:dd:c25:c25:dd:dd:dd:2ada/1272c19:dd:c25:c25:dd:dd:dd:2adb
1112c19:dd:c25:c25:dd:dd:dd:2adc/1272c19:dd:c25:c25:dd:dd:dd:2add
1122c19:dd:c25:c25:dd:dd:dd:2ade/1272c19:dd:c25:c25:dd:dd:dd:2adf
1132c19:dd:c25:c25:dd:dd:dd:2ae0/1272c19:dd:c25:c25:dd:dd:dd:2ae1
1142c19:dd:c25:c25:dd:dd:dd:2ae2/1272c19:dd:c25:c25:dd:dd:dd:2ae3
1152c19:dd:c25:c25:dd:dd:dd:2ae4/1272c19:dd:c25:c25:dd:dd:dd:2ae5
1162c19:dd:c25:c25:dd:dd:dd:2ae6/1272c19:dd:c25:c25:dd:dd:dd:2ae7
1172c19:dd:c25:c25:dd:dd:dd:2ae8/1272c19:dd:c25:c25:dd:dd:dd:2ae9
1182c19:dd:c25:c25:dd:dd:dd:2aea/1272c19:dd:c25:c25:dd:dd:dd:2aeb
1192c19:dd:c25:c25:dd:dd:dd:2aec/1272c19:dd:c25:c25:dd:dd:dd:2aed
1202c19:dd:c25:c25:dd:dd:dd:2aee/1272c19:dd:c25:c25:dd:dd:dd:2aef
1212c19:dd:c25:c25:dd:dd:dd:2af0/1272c19:dd:c25:c25:dd:dd:dd:2af1
1222c19:dd:c25:c25:dd:dd:dd:2af2/1272c19:dd:c25:c25:dd:dd:dd:2af3
1232c19:dd:c25:c25:dd:dd:dd:2af4/1272c19:dd:c25:c25:dd:dd:dd:2af5
1242c19:dd:c25:c25:dd:dd:dd:2af6/1272c19:dd:c25:c25:dd:dd:dd:2af7
1252c19:dd:c25:c25:dd:dd:dd:2af8/1272c19:dd:c25:c25:dd:dd:dd:2af9
1262c19:dd:c25:c25:dd:dd:dd:2afa/1272c19:dd:c25:c25:dd:dd:dd:2afb
1272c19:dd:c25:c25:dd:dd:dd:2afc/1272c19:dd:c25:c25:dd:dd:dd:2afd
1282c19:dd:c25:c25:dd:dd:dd:2afe/1272c19:dd:c25:c25:dd:dd:dd:2aff
1292c19:dd:c25:c25:dd:dd:dd:2b00/1272c19:dd:c25:c25:dd:dd:dd:2b01
1302c19:dd:c25:c25:dd:dd:dd:2b02/1272c19:dd:c25:c25:dd:dd:dd:2b03
1312c19:dd:c25:c25:dd:dd:dd:2b04/1272c19:dd:c25:c25:dd:dd:dd:2b05
1322c19:dd:c25:c25:dd:dd:dd:2b06/1272c19:dd:c25:c25:dd:dd:dd:2b07
1332c19:dd:c25:c25:dd:dd:dd:2b08/1272c19:dd:c25:c25:dd:dd:dd:2b09
1342c19:dd:c25:c25:dd:dd:dd:2b0a/1272c19:dd:c25:c25:dd:dd:dd:2b0b
1352c19:dd:c25:c25:dd:dd:dd:2b0c/1272c19:dd:c25:c25:dd:dd:dd:2b0d
1362c19:dd:c25:c25:dd:dd:dd:2b0e/1272c19:dd:c25:c25:dd:dd:dd:2b0f
1372c19:dd:c25:c25:dd:dd:dd:2b10/1272c19:dd:c25:c25:dd:dd:dd:2b11
1382c19:dd:c25:c25:dd:dd:dd:2b12/1272c19:dd:c25:c25:dd:dd:dd:2b13
1392c19:dd:c25:c25:dd:dd:dd:2b14/1272c19:dd:c25:c25:dd:dd:dd:2b15
1402c19:dd:c25:c25:dd:dd:dd:2b16/1272c19:dd:c25:c25:dd:dd:dd:2b17
1412c19:dd:c25:c25:dd:dd:dd:2b18/1272c19:dd:c25:c25:dd:dd:dd:2b19
1422c19:dd:c25:c25:dd:dd:dd:2b1a/1272c19:dd:c25:c25:dd:dd:dd:2b1b
1432c19:dd:c25:c25:dd:dd:dd:2b1c/1272c19:dd:c25:c25:dd:dd:dd:2b1d
1442c19:dd:c25:c25:dd:dd:dd:2b1e/1272c19:dd:c25:c25:dd:dd:dd:2b1f
1452c19:dd:c25:c25:dd:dd:dd:2b20/1272c19:dd:c25:c25:dd:dd:dd:2b21
1462c19:dd:c25:c25:dd:dd:dd:2b22/1272c19:dd:c25:c25:dd:dd:dd:2b23
1472c19:dd:c25:c25:dd:dd:dd:2b24/1272c19:dd:c25:c25:dd:dd:dd:2b25
1482c19:dd:c25:c25:dd:dd:dd:2b26/1272c19:dd:c25:c25:dd:dd:dd:2b27
1492c19:dd:c25:c25:dd:dd:dd:2b28/1272c19:dd:c25:c25:dd:dd:dd:2b29
1502c19:dd:c25:c25:dd:dd:dd:2b2a/1272c19:dd:c25:c25:dd:dd:dd:2b2b
1512c19:dd:c25:c25:dd:dd:dd:2b2c/1272c19:dd:c25:c25:dd:dd:dd:2b2d
1522c19:dd:c25:c25:dd:dd:dd:2b2e/1272c19:dd:c25:c25:dd:dd:dd:2b2f
1532c19:dd:c25:c25:dd:dd:dd:2b30/1272c19:dd:c25:c25:dd:dd:dd:2b31
1542c19:dd:c25:c25:dd:dd:dd:2b32/1272c19:dd:c25:c25:dd:dd:dd:2b33
1552c19:dd:c25:c25:dd:dd:dd:2b34/1272c19:dd:c25:c25:dd:dd:dd:2b35
1562c19:dd:c25:c25:dd:dd:dd:2b36/1272c19:dd:c25:c25:dd:dd:dd:2b37
1572c19:dd:c25:c25:dd:dd:dd:2b38/1272c19:dd:c25:c25:dd:dd:dd:2b39
1582c19:dd:c25:c25:dd:dd:dd:2b3a/1272c19:dd:c25:c25:dd:dd:dd:2b3b
1592c19:dd:c25:c25:dd:dd:dd:2b3c/1272c19:dd:c25:c25:dd:dd:dd:2b3d
1602c19:dd:c25:c25:dd:dd:dd:2b3e/1272c19:dd:c25:c25:dd:dd:dd:2b3f
1612c19:dd:c25:c25:dd:dd:dd:2b40/1272c19:dd:c25:c25:dd:dd:dd:2b41
1622c19:dd:c25:c25:dd:dd:dd:2b42/1272c19:dd:c25:c25:dd:dd:dd:2b43
1632c19:dd:c25:c25:dd:dd:dd:2b44/1272c19:dd:c25:c25:dd:dd:dd:2b45
1642c19:dd:c25:c25:dd:dd:dd:2b46/1272c19:dd:c25:c25:dd:dd:dd:2b47
1652c19:dd:c25:c25:dd:dd:dd:2b48/1272c19:dd:c25:c25:dd:dd:dd:2b49
1662c19:dd:c25:c25:dd:dd:dd:2b4a/1272c19:dd:c25:c25:dd:dd:dd:2b4b
1672c19:dd:c25:c25:dd:dd:dd:2b4c/1272c19:dd:c25:c25:dd:dd:dd:2b4d
1682c19:dd:c25:c25:dd:dd:dd:2b4e/1272c19:dd:c25:c25:dd:dd:dd:2b4f
1692c19:dd:c25:c25:dd:dd:dd:2b50/1272c19:dd:c25:c25:dd:dd:dd:2b51
1702c19:dd:c25:c25:dd:dd:dd:2b52/1272c19:dd:c25:c25:dd:dd:dd:2b53
1712c19:dd:c25:c25:dd:dd:dd:2b54/1272c19:dd:c25:c25:dd:dd:dd:2b55
1722c19:dd:c25:c25:dd:dd:dd:2b56/1272c19:dd:c25:c25:dd:dd:dd:2b57
1732c19:dd:c25:c25:dd:dd:dd:2b58/1272c19:dd:c25:c25:dd:dd:dd:2b59
1742c19:dd:c25:c25:dd:dd:dd:2b5a/1272c19:dd:c25:c25:dd:dd:dd:2b5b
1752c19:dd:c25:c25:dd:dd:dd:2b5c/1272c19:dd:c25:c25:dd:dd:dd:2b5d
1762c19:dd:c25:c25:dd:dd:dd:2b5e/1272c19:dd:c25:c25:dd:dd:dd:2b5f
1772c19:dd:c25:c25:dd:dd:dd:2b60/1272c19:dd:c25:c25:dd:dd:dd:2b61
1782c19:dd:c25:c25:dd:dd:dd:2b62/1272c19:dd:c25:c25:dd:dd:dd:2b63
1792c19:dd:c25:c25:dd:dd:dd:2b64/1272c19:dd:c25:c25:dd:dd:dd:2b65
1802c19:dd:c25:c25:dd:dd:dd:2b66/1272c19:dd:c25:c25:dd:dd:dd:2b67
1812c19:dd:c25:c25:dd:dd:dd:2b68/1272c19:dd:c25:c25:dd:dd:dd:2b69
1822c19:dd:c25:c25:dd:dd:dd:2b6a/1272c19:dd:c25:c25:dd:dd:dd:2b6b
1832c19:dd:c25:c25:dd:dd:dd:2b6c/1272c19:dd:c25:c25:dd:dd:dd:2b6d
1842c19:dd:c25:c25:dd:dd:dd:2b6e/1272c19:dd:c25:c25:dd:dd:dd:2b6f
1852c19:dd:c25:c25:dd:dd:dd:2b70/1272c19:dd:c25:c25:dd:dd:dd:2b71
1862c19:dd:c25:c25:dd:dd:dd:2b72/1272c19:dd:c25:c25:dd:dd:dd:2b73
1872c19:dd:c25:c25:dd:dd:dd:2b74/1272c19:dd:c25:c25:dd:dd:dd:2b75
1882c19:dd:c25:c25:dd:dd:dd:2b76/1272c19:dd:c25:c25:dd:dd:dd:2b77
1892c19:dd:c25:c25:dd:dd:dd:2b78/1272c19:dd:c25:c25:dd:dd:dd:2b79
1902c19:dd:c25:c25:dd:dd:dd:2b7a/1272c19:dd:c25:c25:dd:dd:dd:2b7b
1912c19:dd:c25:c25:dd:dd:dd:2b7c/1272c19:dd:c25:c25:dd:dd:dd:2b7d
1922c19:dd:c25:c25:dd:dd:dd:2b7e/1272c19:dd:c25:c25:dd:dd:dd:2b7f
1932c19:dd:c25:c25:dd:dd:dd:2b80/1272c19:dd:c25:c25:dd:dd:dd:2b81
1942c19:dd:c25:c25:dd:dd:dd:2b82/1272c19:dd:c25:c25:dd:dd:dd:2b83
1952c19:dd:c25:c25:dd:dd:dd:2b84/1272c19:dd:c25:c25:dd:dd:dd:2b85
1962c19:dd:c25:c25:dd:dd:dd:2b86/1272c19:dd:c25:c25:dd:dd:dd:2b87
1972c19:dd:c25:c25:dd:dd:dd:2b88/1272c19:dd:c25:c25:dd:dd:dd:2b89
1982c19:dd:c25:c25:dd:dd:dd:2b8a/1272c19:dd:c25:c25:dd:dd:dd:2b8b
1992c19:dd:c25:c25:dd:dd:dd:2b8c/1272c19:dd:c25:c25:dd:dd:dd:2b8d
2002c19:dd:c25:c25:dd:dd:dd:2b8e/1272c19:dd:c25:c25:dd:dd:dd:2b8f
2012c19:dd:c25:c25:dd:dd:dd:2b90/1272c19:dd:c25:c25:dd:dd:dd:2b91
2022c19:dd:c25:c25:dd:dd:dd:2b92/1272c19:dd:c25:c25:dd:dd:dd:2b93
2032c19:dd:c25:c25:dd:dd:dd:2b94/1272c19:dd:c25:c25:dd:dd:dd:2b95
2042c19:dd:c25:c25:dd:dd:dd:2b96/1272c19:dd:c25:c25:dd:dd:dd:2b97
2052c19:dd:c25:c25:dd:dd:dd:2b98/1272c19:dd:c25:c25:dd:dd:dd:2b99
2062c19:dd:c25:c25:dd:dd:dd:2b9a/1272c19:dd:c25:c25:dd:dd:dd:2b9b
2072c19:dd:c25:c25:dd:dd:dd:2b9c/1272c19:dd:c25:c25:dd:dd:dd:2b9d
2082c19:dd:c25:c25:dd:dd:dd:2b9e/1272c19:dd:c25:c25:dd:dd:dd:2b9f
2092c19:dd:c25:c25:dd:dd:dd:2ba0/1272c19:dd:c25:c25:dd:dd:dd:2ba1
2102c19:dd:c25:c25:dd:dd:dd:2ba2/1272c19:dd:c25:c25:dd:dd:dd:2ba3
2112c19:dd:c25:c25:dd:dd:dd:2ba4/1272c19:dd:c25:c25:dd:dd:dd:2ba5
2122c19:dd:c25:c25:dd:dd:dd:2ba6/1272c19:dd:c25:c25:dd:dd:dd:2ba7
2132c19:dd:c25:c25:dd:dd:dd:2ba8/1272c19:dd:c25:c25:dd:dd:dd:2ba9
2142c19:dd:c25:c25:dd:dd:dd:2baa/1272c19:dd:c25:c25:dd:dd:dd:2bab
2152c19:dd:c25:c25:dd:dd:dd:2bac/1272c19:dd:c25:c25:dd:dd:dd:2bad
2162c19:dd:c25:c25:dd:dd:dd:2bae/1272c19:dd:c25:c25:dd:dd:dd:2baf
2172c19:dd:c25:c25:dd:dd:dd:2bb0/1272c19:dd:c25:c25:dd:dd:dd:2bb1
2182c19:dd:c25:c25:dd:dd:dd:2bb2/1272c19:dd:c25:c25:dd:dd:dd:2bb3
2192c19:dd:c25:c25:dd:dd:dd:2bb4/1272c19:dd:c25:c25:dd:dd:dd:2bb5
2202c19:dd:c25:c25:dd:dd:dd:2bb6/1272c19:dd:c25:c25:dd:dd:dd:2bb7
2212c19:dd:c25:c25:dd:dd:dd:2bb8/1272c19:dd:c25:c25:dd:dd:dd:2bb9
2222c19:dd:c25:c25:dd:dd:dd:2bba/1272c19:dd:c25:c25:dd:dd:dd:2bbb
2232c19:dd:c25:c25:dd:dd:dd:2bbc/1272c19:dd:c25:c25:dd:dd:dd:2bbd
2242c19:dd:c25:c25:dd:dd:dd:2bbe/1272c19:dd:c25:c25:dd:dd:dd:2bbf
2252c19:dd:c25:c25:dd:dd:dd:2bc0/1272c19:dd:c25:c25:dd:dd:dd:2bc1
2262c19:dd:c25:c25:dd:dd:dd:2bc2/1272c19:dd:c25:c25:dd:dd:dd:2bc3
2272c19:dd:c25:c25:dd:dd:dd:2bc4/1272c19:dd:c25:c25:dd:dd:dd:2bc5
2282c19:dd:c25:c25:dd:dd:dd:2bc6/1272c19:dd:c25:c25:dd:dd:dd:2bc7
2292c19:dd:c25:c25:dd:dd:dd:2bc8/1272c19:dd:c25:c25:dd:dd:dd:2bc9
2302c19:dd:c25:c25:dd:dd:dd:2bca/1272c19:dd:c25:c25:dd:dd:dd:2bcb
2312c19:dd:c25:c25:dd:dd:dd:2bcc/1272c19:dd:c25:c25:dd:dd:dd:2bcd
2322c19:dd:c25:c25:dd:dd:dd:2bce/1272c19:dd:c25:c25:dd:dd:dd:2bcf
2332c19:dd:c25:c25:dd:dd:dd:2bd0/1272c19:dd:c25:c25:dd:dd:dd:2bd1
2342c19:dd:c25:c25:dd:dd:dd:2bd2/1272c19:dd:c25:c25:dd:dd:dd:2bd3
2352c19:dd:c25:c25:dd:dd:dd:2bd4/1272c19:dd:c25:c25:dd:dd:dd:2bd5
2362c19:dd:c25:c25:dd:dd:dd:2bd6/1272c19:dd:c25:c25:dd:dd:dd:2bd7
2372c19:dd:c25:c25:dd:dd:dd:2bd8/1272c19:dd:c25:c25:dd:dd:dd:2bd9
2382c19:dd:c25:c25:dd:dd:dd:2bda/1272c19:dd:c25:c25:dd:dd:dd:2bdb
2392c19:dd:c25:c25:dd:dd:dd:2bdc/1272c19:dd:c25:c25:dd:dd:dd:2bdd
2402c19:dd:c25:c25:dd:dd:dd:2bde/1272c19:dd:c25:c25:dd:dd:dd:2bdf
2412c19:dd:c25:c25:dd:dd:dd:2be0/1272c19:dd:c25:c25:dd:dd:dd:2be1
2422c19:dd:c25:c25:dd:dd:dd:2be2/1272c19:dd:c25:c25:dd:dd:dd:2be3
2432c19:dd:c25:c25:dd:dd:dd:2be4/1272c19:dd:c25:c25:dd:dd:dd:2be5
2442c19:dd:c25:c25:dd:dd:dd:2be6/1272c19:dd:c25:c25:dd:dd:dd:2be7
2452c19:dd:c25:c25:dd:dd:dd:2be8/1272c19:dd:c25:c25:dd:dd:dd:2be9
2462c19:dd:c25:c25:dd:dd:dd:2bea/1272c19:dd:c25:c25:dd:dd:dd:2beb
2472c19:dd:c25:c25:dd:dd:dd:2bec/1272c19:dd:c25:c25:dd:dd:dd:2bed
2482c19:dd:c25:c25:dd:dd:dd:2bee/1272c19:dd:c25:c25:dd:dd:dd:2bef
2492c19:dd:c25:c25:dd:dd:dd:2bf0/1272c19:dd:c25:c25:dd:dd:dd:2bf1
2502c19:dd:c25:c25:dd:dd:dd:2bf2/1272c19:dd:c25:c25:dd:dd:dd:2bf3
2512c19:dd:c25:c25:dd:dd:dd:2bf4/1272c19:dd:c25:c25:dd:dd:dd:2bf5
2522c19:dd:c25:c25:dd:dd:dd:2bf6/1272c19:dd:c25:c25:dd:dd:dd:2bf7
2532c19:dd:c25:c25:dd:dd:dd:2bf8/1272c19:dd:c25:c25:dd:dd:dd:2bf9
2542c19:dd:c25:c25:dd:dd:dd:2bfa/1272c19:dd:c25:c25:dd:dd:dd:2bfb
2552c19:dd:c25:c25:dd:dd:dd:2bfc/1272c19:dd:c25:c25:dd:dd:dd:2bfd
2562c19:dd:c25:c25:dd:dd:dd:2bfe/1272c19:dd:c25:c25:dd:dd:dd:2bff

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.