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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:c25d:dd:dd:dd:8a00/119
First address
2c19:dd:c25:c25d:dd:dd:dd:8a00
Last address
2c19:dd:c25:c25d:dd:dd:dd:8bff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:8a00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
a.8.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
b.8.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.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:c25d:dd:dd:dd:8a00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:8a00/1272c19:dd:c25:c25d:dd:dd:dd:8a01
22c19:dd:c25:c25d:dd:dd:dd:8a02/1272c19:dd:c25:c25d:dd:dd:dd:8a03
32c19:dd:c25:c25d:dd:dd:dd:8a04/1272c19:dd:c25:c25d:dd:dd:dd:8a05
42c19:dd:c25:c25d:dd:dd:dd:8a06/1272c19:dd:c25:c25d:dd:dd:dd:8a07
52c19:dd:c25:c25d:dd:dd:dd:8a08/1272c19:dd:c25:c25d:dd:dd:dd:8a09
62c19:dd:c25:c25d:dd:dd:dd:8a0a/1272c19:dd:c25:c25d:dd:dd:dd:8a0b
72c19:dd:c25:c25d:dd:dd:dd:8a0c/1272c19:dd:c25:c25d:dd:dd:dd:8a0d
82c19:dd:c25:c25d:dd:dd:dd:8a0e/1272c19:dd:c25:c25d:dd:dd:dd:8a0f
92c19:dd:c25:c25d:dd:dd:dd:8a10/1272c19:dd:c25:c25d:dd:dd:dd:8a11
102c19:dd:c25:c25d:dd:dd:dd:8a12/1272c19:dd:c25:c25d:dd:dd:dd:8a13
112c19:dd:c25:c25d:dd:dd:dd:8a14/1272c19:dd:c25:c25d:dd:dd:dd:8a15
122c19:dd:c25:c25d:dd:dd:dd:8a16/1272c19:dd:c25:c25d:dd:dd:dd:8a17
132c19:dd:c25:c25d:dd:dd:dd:8a18/1272c19:dd:c25:c25d:dd:dd:dd:8a19
142c19:dd:c25:c25d:dd:dd:dd:8a1a/1272c19:dd:c25:c25d:dd:dd:dd:8a1b
152c19:dd:c25:c25d:dd:dd:dd:8a1c/1272c19:dd:c25:c25d:dd:dd:dd:8a1d
162c19:dd:c25:c25d:dd:dd:dd:8a1e/1272c19:dd:c25:c25d:dd:dd:dd:8a1f
172c19:dd:c25:c25d:dd:dd:dd:8a20/1272c19:dd:c25:c25d:dd:dd:dd:8a21
182c19:dd:c25:c25d:dd:dd:dd:8a22/1272c19:dd:c25:c25d:dd:dd:dd:8a23
192c19:dd:c25:c25d:dd:dd:dd:8a24/1272c19:dd:c25:c25d:dd:dd:dd:8a25
202c19:dd:c25:c25d:dd:dd:dd:8a26/1272c19:dd:c25:c25d:dd:dd:dd:8a27
212c19:dd:c25:c25d:dd:dd:dd:8a28/1272c19:dd:c25:c25d:dd:dd:dd:8a29
222c19:dd:c25:c25d:dd:dd:dd:8a2a/1272c19:dd:c25:c25d:dd:dd:dd:8a2b
232c19:dd:c25:c25d:dd:dd:dd:8a2c/1272c19:dd:c25:c25d:dd:dd:dd:8a2d
242c19:dd:c25:c25d:dd:dd:dd:8a2e/1272c19:dd:c25:c25d:dd:dd:dd:8a2f
252c19:dd:c25:c25d:dd:dd:dd:8a30/1272c19:dd:c25:c25d:dd:dd:dd:8a31
262c19:dd:c25:c25d:dd:dd:dd:8a32/1272c19:dd:c25:c25d:dd:dd:dd:8a33
272c19:dd:c25:c25d:dd:dd:dd:8a34/1272c19:dd:c25:c25d:dd:dd:dd:8a35
282c19:dd:c25:c25d:dd:dd:dd:8a36/1272c19:dd:c25:c25d:dd:dd:dd:8a37
292c19:dd:c25:c25d:dd:dd:dd:8a38/1272c19:dd:c25:c25d:dd:dd:dd:8a39
302c19:dd:c25:c25d:dd:dd:dd:8a3a/1272c19:dd:c25:c25d:dd:dd:dd:8a3b
312c19:dd:c25:c25d:dd:dd:dd:8a3c/1272c19:dd:c25:c25d:dd:dd:dd:8a3d
322c19:dd:c25:c25d:dd:dd:dd:8a3e/1272c19:dd:c25:c25d:dd:dd:dd:8a3f
332c19:dd:c25:c25d:dd:dd:dd:8a40/1272c19:dd:c25:c25d:dd:dd:dd:8a41
342c19:dd:c25:c25d:dd:dd:dd:8a42/1272c19:dd:c25:c25d:dd:dd:dd:8a43
352c19:dd:c25:c25d:dd:dd:dd:8a44/1272c19:dd:c25:c25d:dd:dd:dd:8a45
362c19:dd:c25:c25d:dd:dd:dd:8a46/1272c19:dd:c25:c25d:dd:dd:dd:8a47
372c19:dd:c25:c25d:dd:dd:dd:8a48/1272c19:dd:c25:c25d:dd:dd:dd:8a49
382c19:dd:c25:c25d:dd:dd:dd:8a4a/1272c19:dd:c25:c25d:dd:dd:dd:8a4b
392c19:dd:c25:c25d:dd:dd:dd:8a4c/1272c19:dd:c25:c25d:dd:dd:dd:8a4d
402c19:dd:c25:c25d:dd:dd:dd:8a4e/1272c19:dd:c25:c25d:dd:dd:dd:8a4f
412c19:dd:c25:c25d:dd:dd:dd:8a50/1272c19:dd:c25:c25d:dd:dd:dd:8a51
422c19:dd:c25:c25d:dd:dd:dd:8a52/1272c19:dd:c25:c25d:dd:dd:dd:8a53
432c19:dd:c25:c25d:dd:dd:dd:8a54/1272c19:dd:c25:c25d:dd:dd:dd:8a55
442c19:dd:c25:c25d:dd:dd:dd:8a56/1272c19:dd:c25:c25d:dd:dd:dd:8a57
452c19:dd:c25:c25d:dd:dd:dd:8a58/1272c19:dd:c25:c25d:dd:dd:dd:8a59
462c19:dd:c25:c25d:dd:dd:dd:8a5a/1272c19:dd:c25:c25d:dd:dd:dd:8a5b
472c19:dd:c25:c25d:dd:dd:dd:8a5c/1272c19:dd:c25:c25d:dd:dd:dd:8a5d
482c19:dd:c25:c25d:dd:dd:dd:8a5e/1272c19:dd:c25:c25d:dd:dd:dd:8a5f
492c19:dd:c25:c25d:dd:dd:dd:8a60/1272c19:dd:c25:c25d:dd:dd:dd:8a61
502c19:dd:c25:c25d:dd:dd:dd:8a62/1272c19:dd:c25:c25d:dd:dd:dd:8a63
512c19:dd:c25:c25d:dd:dd:dd:8a64/1272c19:dd:c25:c25d:dd:dd:dd:8a65
522c19:dd:c25:c25d:dd:dd:dd:8a66/1272c19:dd:c25:c25d:dd:dd:dd:8a67
532c19:dd:c25:c25d:dd:dd:dd:8a68/1272c19:dd:c25:c25d:dd:dd:dd:8a69
542c19:dd:c25:c25d:dd:dd:dd:8a6a/1272c19:dd:c25:c25d:dd:dd:dd:8a6b
552c19:dd:c25:c25d:dd:dd:dd:8a6c/1272c19:dd:c25:c25d:dd:dd:dd:8a6d
562c19:dd:c25:c25d:dd:dd:dd:8a6e/1272c19:dd:c25:c25d:dd:dd:dd:8a6f
572c19:dd:c25:c25d:dd:dd:dd:8a70/1272c19:dd:c25:c25d:dd:dd:dd:8a71
582c19:dd:c25:c25d:dd:dd:dd:8a72/1272c19:dd:c25:c25d:dd:dd:dd:8a73
592c19:dd:c25:c25d:dd:dd:dd:8a74/1272c19:dd:c25:c25d:dd:dd:dd:8a75
602c19:dd:c25:c25d:dd:dd:dd:8a76/1272c19:dd:c25:c25d:dd:dd:dd:8a77
612c19:dd:c25:c25d:dd:dd:dd:8a78/1272c19:dd:c25:c25d:dd:dd:dd:8a79
622c19:dd:c25:c25d:dd:dd:dd:8a7a/1272c19:dd:c25:c25d:dd:dd:dd:8a7b
632c19:dd:c25:c25d:dd:dd:dd:8a7c/1272c19:dd:c25:c25d:dd:dd:dd:8a7d
642c19:dd:c25:c25d:dd:dd:dd:8a7e/1272c19:dd:c25:c25d:dd:dd:dd:8a7f
652c19:dd:c25:c25d:dd:dd:dd:8a80/1272c19:dd:c25:c25d:dd:dd:dd:8a81
662c19:dd:c25:c25d:dd:dd:dd:8a82/1272c19:dd:c25:c25d:dd:dd:dd:8a83
672c19:dd:c25:c25d:dd:dd:dd:8a84/1272c19:dd:c25:c25d:dd:dd:dd:8a85
682c19:dd:c25:c25d:dd:dd:dd:8a86/1272c19:dd:c25:c25d:dd:dd:dd:8a87
692c19:dd:c25:c25d:dd:dd:dd:8a88/1272c19:dd:c25:c25d:dd:dd:dd:8a89
702c19:dd:c25:c25d:dd:dd:dd:8a8a/1272c19:dd:c25:c25d:dd:dd:dd:8a8b
712c19:dd:c25:c25d:dd:dd:dd:8a8c/1272c19:dd:c25:c25d:dd:dd:dd:8a8d
722c19:dd:c25:c25d:dd:dd:dd:8a8e/1272c19:dd:c25:c25d:dd:dd:dd:8a8f
732c19:dd:c25:c25d:dd:dd:dd:8a90/1272c19:dd:c25:c25d:dd:dd:dd:8a91
742c19:dd:c25:c25d:dd:dd:dd:8a92/1272c19:dd:c25:c25d:dd:dd:dd:8a93
752c19:dd:c25:c25d:dd:dd:dd:8a94/1272c19:dd:c25:c25d:dd:dd:dd:8a95
762c19:dd:c25:c25d:dd:dd:dd:8a96/1272c19:dd:c25:c25d:dd:dd:dd:8a97
772c19:dd:c25:c25d:dd:dd:dd:8a98/1272c19:dd:c25:c25d:dd:dd:dd:8a99
782c19:dd:c25:c25d:dd:dd:dd:8a9a/1272c19:dd:c25:c25d:dd:dd:dd:8a9b
792c19:dd:c25:c25d:dd:dd:dd:8a9c/1272c19:dd:c25:c25d:dd:dd:dd:8a9d
802c19:dd:c25:c25d:dd:dd:dd:8a9e/1272c19:dd:c25:c25d:dd:dd:dd:8a9f
812c19:dd:c25:c25d:dd:dd:dd:8aa0/1272c19:dd:c25:c25d:dd:dd:dd:8aa1
822c19:dd:c25:c25d:dd:dd:dd:8aa2/1272c19:dd:c25:c25d:dd:dd:dd:8aa3
832c19:dd:c25:c25d:dd:dd:dd:8aa4/1272c19:dd:c25:c25d:dd:dd:dd:8aa5
842c19:dd:c25:c25d:dd:dd:dd:8aa6/1272c19:dd:c25:c25d:dd:dd:dd:8aa7
852c19:dd:c25:c25d:dd:dd:dd:8aa8/1272c19:dd:c25:c25d:dd:dd:dd:8aa9
862c19:dd:c25:c25d:dd:dd:dd:8aaa/1272c19:dd:c25:c25d:dd:dd:dd:8aab
872c19:dd:c25:c25d:dd:dd:dd:8aac/1272c19:dd:c25:c25d:dd:dd:dd:8aad
882c19:dd:c25:c25d:dd:dd:dd:8aae/1272c19:dd:c25:c25d:dd:dd:dd:8aaf
892c19:dd:c25:c25d:dd:dd:dd:8ab0/1272c19:dd:c25:c25d:dd:dd:dd:8ab1
902c19:dd:c25:c25d:dd:dd:dd:8ab2/1272c19:dd:c25:c25d:dd:dd:dd:8ab3
912c19:dd:c25:c25d:dd:dd:dd:8ab4/1272c19:dd:c25:c25d:dd:dd:dd:8ab5
922c19:dd:c25:c25d:dd:dd:dd:8ab6/1272c19:dd:c25:c25d:dd:dd:dd:8ab7
932c19:dd:c25:c25d:dd:dd:dd:8ab8/1272c19:dd:c25:c25d:dd:dd:dd:8ab9
942c19:dd:c25:c25d:dd:dd:dd:8aba/1272c19:dd:c25:c25d:dd:dd:dd:8abb
952c19:dd:c25:c25d:dd:dd:dd:8abc/1272c19:dd:c25:c25d:dd:dd:dd:8abd
962c19:dd:c25:c25d:dd:dd:dd:8abe/1272c19:dd:c25:c25d:dd:dd:dd:8abf
972c19:dd:c25:c25d:dd:dd:dd:8ac0/1272c19:dd:c25:c25d:dd:dd:dd:8ac1
982c19:dd:c25:c25d:dd:dd:dd:8ac2/1272c19:dd:c25:c25d:dd:dd:dd:8ac3
992c19:dd:c25:c25d:dd:dd:dd:8ac4/1272c19:dd:c25:c25d:dd:dd:dd:8ac5
1002c19:dd:c25:c25d:dd:dd:dd:8ac6/1272c19:dd:c25:c25d:dd:dd:dd:8ac7
1012c19:dd:c25:c25d:dd:dd:dd:8ac8/1272c19:dd:c25:c25d:dd:dd:dd:8ac9
1022c19:dd:c25:c25d:dd:dd:dd:8aca/1272c19:dd:c25:c25d:dd:dd:dd:8acb
1032c19:dd:c25:c25d:dd:dd:dd:8acc/1272c19:dd:c25:c25d:dd:dd:dd:8acd
1042c19:dd:c25:c25d:dd:dd:dd:8ace/1272c19:dd:c25:c25d:dd:dd:dd:8acf
1052c19:dd:c25:c25d:dd:dd:dd:8ad0/1272c19:dd:c25:c25d:dd:dd:dd:8ad1
1062c19:dd:c25:c25d:dd:dd:dd:8ad2/1272c19:dd:c25:c25d:dd:dd:dd:8ad3
1072c19:dd:c25:c25d:dd:dd:dd:8ad4/1272c19:dd:c25:c25d:dd:dd:dd:8ad5
1082c19:dd:c25:c25d:dd:dd:dd:8ad6/1272c19:dd:c25:c25d:dd:dd:dd:8ad7
1092c19:dd:c25:c25d:dd:dd:dd:8ad8/1272c19:dd:c25:c25d:dd:dd:dd:8ad9
1102c19:dd:c25:c25d:dd:dd:dd:8ada/1272c19:dd:c25:c25d:dd:dd:dd:8adb
1112c19:dd:c25:c25d:dd:dd:dd:8adc/1272c19:dd:c25:c25d:dd:dd:dd:8add
1122c19:dd:c25:c25d:dd:dd:dd:8ade/1272c19:dd:c25:c25d:dd:dd:dd:8adf
1132c19:dd:c25:c25d:dd:dd:dd:8ae0/1272c19:dd:c25:c25d:dd:dd:dd:8ae1
1142c19:dd:c25:c25d:dd:dd:dd:8ae2/1272c19:dd:c25:c25d:dd:dd:dd:8ae3
1152c19:dd:c25:c25d:dd:dd:dd:8ae4/1272c19:dd:c25:c25d:dd:dd:dd:8ae5
1162c19:dd:c25:c25d:dd:dd:dd:8ae6/1272c19:dd:c25:c25d:dd:dd:dd:8ae7
1172c19:dd:c25:c25d:dd:dd:dd:8ae8/1272c19:dd:c25:c25d:dd:dd:dd:8ae9
1182c19:dd:c25:c25d:dd:dd:dd:8aea/1272c19:dd:c25:c25d:dd:dd:dd:8aeb
1192c19:dd:c25:c25d:dd:dd:dd:8aec/1272c19:dd:c25:c25d:dd:dd:dd:8aed
1202c19:dd:c25:c25d:dd:dd:dd:8aee/1272c19:dd:c25:c25d:dd:dd:dd:8aef
1212c19:dd:c25:c25d:dd:dd:dd:8af0/1272c19:dd:c25:c25d:dd:dd:dd:8af1
1222c19:dd:c25:c25d:dd:dd:dd:8af2/1272c19:dd:c25:c25d:dd:dd:dd:8af3
1232c19:dd:c25:c25d:dd:dd:dd:8af4/1272c19:dd:c25:c25d:dd:dd:dd:8af5
1242c19:dd:c25:c25d:dd:dd:dd:8af6/1272c19:dd:c25:c25d:dd:dd:dd:8af7
1252c19:dd:c25:c25d:dd:dd:dd:8af8/1272c19:dd:c25:c25d:dd:dd:dd:8af9
1262c19:dd:c25:c25d:dd:dd:dd:8afa/1272c19:dd:c25:c25d:dd:dd:dd:8afb
1272c19:dd:c25:c25d:dd:dd:dd:8afc/1272c19:dd:c25:c25d:dd:dd:dd:8afd
1282c19:dd:c25:c25d:dd:dd:dd:8afe/1272c19:dd:c25:c25d:dd:dd:dd:8aff
1292c19:dd:c25:c25d:dd:dd:dd:8b00/1272c19:dd:c25:c25d:dd:dd:dd:8b01
1302c19:dd:c25:c25d:dd:dd:dd:8b02/1272c19:dd:c25:c25d:dd:dd:dd:8b03
1312c19:dd:c25:c25d:dd:dd:dd:8b04/1272c19:dd:c25:c25d:dd:dd:dd:8b05
1322c19:dd:c25:c25d:dd:dd:dd:8b06/1272c19:dd:c25:c25d:dd:dd:dd:8b07
1332c19:dd:c25:c25d:dd:dd:dd:8b08/1272c19:dd:c25:c25d:dd:dd:dd:8b09
1342c19:dd:c25:c25d:dd:dd:dd:8b0a/1272c19:dd:c25:c25d:dd:dd:dd:8b0b
1352c19:dd:c25:c25d:dd:dd:dd:8b0c/1272c19:dd:c25:c25d:dd:dd:dd:8b0d
1362c19:dd:c25:c25d:dd:dd:dd:8b0e/1272c19:dd:c25:c25d:dd:dd:dd:8b0f
1372c19:dd:c25:c25d:dd:dd:dd:8b10/1272c19:dd:c25:c25d:dd:dd:dd:8b11
1382c19:dd:c25:c25d:dd:dd:dd:8b12/1272c19:dd:c25:c25d:dd:dd:dd:8b13
1392c19:dd:c25:c25d:dd:dd:dd:8b14/1272c19:dd:c25:c25d:dd:dd:dd:8b15
1402c19:dd:c25:c25d:dd:dd:dd:8b16/1272c19:dd:c25:c25d:dd:dd:dd:8b17
1412c19:dd:c25:c25d:dd:dd:dd:8b18/1272c19:dd:c25:c25d:dd:dd:dd:8b19
1422c19:dd:c25:c25d:dd:dd:dd:8b1a/1272c19:dd:c25:c25d:dd:dd:dd:8b1b
1432c19:dd:c25:c25d:dd:dd:dd:8b1c/1272c19:dd:c25:c25d:dd:dd:dd:8b1d
1442c19:dd:c25:c25d:dd:dd:dd:8b1e/1272c19:dd:c25:c25d:dd:dd:dd:8b1f
1452c19:dd:c25:c25d:dd:dd:dd:8b20/1272c19:dd:c25:c25d:dd:dd:dd:8b21
1462c19:dd:c25:c25d:dd:dd:dd:8b22/1272c19:dd:c25:c25d:dd:dd:dd:8b23
1472c19:dd:c25:c25d:dd:dd:dd:8b24/1272c19:dd:c25:c25d:dd:dd:dd:8b25
1482c19:dd:c25:c25d:dd:dd:dd:8b26/1272c19:dd:c25:c25d:dd:dd:dd:8b27
1492c19:dd:c25:c25d:dd:dd:dd:8b28/1272c19:dd:c25:c25d:dd:dd:dd:8b29
1502c19:dd:c25:c25d:dd:dd:dd:8b2a/1272c19:dd:c25:c25d:dd:dd:dd:8b2b
1512c19:dd:c25:c25d:dd:dd:dd:8b2c/1272c19:dd:c25:c25d:dd:dd:dd:8b2d
1522c19:dd:c25:c25d:dd:dd:dd:8b2e/1272c19:dd:c25:c25d:dd:dd:dd:8b2f
1532c19:dd:c25:c25d:dd:dd:dd:8b30/1272c19:dd:c25:c25d:dd:dd:dd:8b31
1542c19:dd:c25:c25d:dd:dd:dd:8b32/1272c19:dd:c25:c25d:dd:dd:dd:8b33
1552c19:dd:c25:c25d:dd:dd:dd:8b34/1272c19:dd:c25:c25d:dd:dd:dd:8b35
1562c19:dd:c25:c25d:dd:dd:dd:8b36/1272c19:dd:c25:c25d:dd:dd:dd:8b37
1572c19:dd:c25:c25d:dd:dd:dd:8b38/1272c19:dd:c25:c25d:dd:dd:dd:8b39
1582c19:dd:c25:c25d:dd:dd:dd:8b3a/1272c19:dd:c25:c25d:dd:dd:dd:8b3b
1592c19:dd:c25:c25d:dd:dd:dd:8b3c/1272c19:dd:c25:c25d:dd:dd:dd:8b3d
1602c19:dd:c25:c25d:dd:dd:dd:8b3e/1272c19:dd:c25:c25d:dd:dd:dd:8b3f
1612c19:dd:c25:c25d:dd:dd:dd:8b40/1272c19:dd:c25:c25d:dd:dd:dd:8b41
1622c19:dd:c25:c25d:dd:dd:dd:8b42/1272c19:dd:c25:c25d:dd:dd:dd:8b43
1632c19:dd:c25:c25d:dd:dd:dd:8b44/1272c19:dd:c25:c25d:dd:dd:dd:8b45
1642c19:dd:c25:c25d:dd:dd:dd:8b46/1272c19:dd:c25:c25d:dd:dd:dd:8b47
1652c19:dd:c25:c25d:dd:dd:dd:8b48/1272c19:dd:c25:c25d:dd:dd:dd:8b49
1662c19:dd:c25:c25d:dd:dd:dd:8b4a/1272c19:dd:c25:c25d:dd:dd:dd:8b4b
1672c19:dd:c25:c25d:dd:dd:dd:8b4c/1272c19:dd:c25:c25d:dd:dd:dd:8b4d
1682c19:dd:c25:c25d:dd:dd:dd:8b4e/1272c19:dd:c25:c25d:dd:dd:dd:8b4f
1692c19:dd:c25:c25d:dd:dd:dd:8b50/1272c19:dd:c25:c25d:dd:dd:dd:8b51
1702c19:dd:c25:c25d:dd:dd:dd:8b52/1272c19:dd:c25:c25d:dd:dd:dd:8b53
1712c19:dd:c25:c25d:dd:dd:dd:8b54/1272c19:dd:c25:c25d:dd:dd:dd:8b55
1722c19:dd:c25:c25d:dd:dd:dd:8b56/1272c19:dd:c25:c25d:dd:dd:dd:8b57
1732c19:dd:c25:c25d:dd:dd:dd:8b58/1272c19:dd:c25:c25d:dd:dd:dd:8b59
1742c19:dd:c25:c25d:dd:dd:dd:8b5a/1272c19:dd:c25:c25d:dd:dd:dd:8b5b
1752c19:dd:c25:c25d:dd:dd:dd:8b5c/1272c19:dd:c25:c25d:dd:dd:dd:8b5d
1762c19:dd:c25:c25d:dd:dd:dd:8b5e/1272c19:dd:c25:c25d:dd:dd:dd:8b5f
1772c19:dd:c25:c25d:dd:dd:dd:8b60/1272c19:dd:c25:c25d:dd:dd:dd:8b61
1782c19:dd:c25:c25d:dd:dd:dd:8b62/1272c19:dd:c25:c25d:dd:dd:dd:8b63
1792c19:dd:c25:c25d:dd:dd:dd:8b64/1272c19:dd:c25:c25d:dd:dd:dd:8b65
1802c19:dd:c25:c25d:dd:dd:dd:8b66/1272c19:dd:c25:c25d:dd:dd:dd:8b67
1812c19:dd:c25:c25d:dd:dd:dd:8b68/1272c19:dd:c25:c25d:dd:dd:dd:8b69
1822c19:dd:c25:c25d:dd:dd:dd:8b6a/1272c19:dd:c25:c25d:dd:dd:dd:8b6b
1832c19:dd:c25:c25d:dd:dd:dd:8b6c/1272c19:dd:c25:c25d:dd:dd:dd:8b6d
1842c19:dd:c25:c25d:dd:dd:dd:8b6e/1272c19:dd:c25:c25d:dd:dd:dd:8b6f
1852c19:dd:c25:c25d:dd:dd:dd:8b70/1272c19:dd:c25:c25d:dd:dd:dd:8b71
1862c19:dd:c25:c25d:dd:dd:dd:8b72/1272c19:dd:c25:c25d:dd:dd:dd:8b73
1872c19:dd:c25:c25d:dd:dd:dd:8b74/1272c19:dd:c25:c25d:dd:dd:dd:8b75
1882c19:dd:c25:c25d:dd:dd:dd:8b76/1272c19:dd:c25:c25d:dd:dd:dd:8b77
1892c19:dd:c25:c25d:dd:dd:dd:8b78/1272c19:dd:c25:c25d:dd:dd:dd:8b79
1902c19:dd:c25:c25d:dd:dd:dd:8b7a/1272c19:dd:c25:c25d:dd:dd:dd:8b7b
1912c19:dd:c25:c25d:dd:dd:dd:8b7c/1272c19:dd:c25:c25d:dd:dd:dd:8b7d
1922c19:dd:c25:c25d:dd:dd:dd:8b7e/1272c19:dd:c25:c25d:dd:dd:dd:8b7f
1932c19:dd:c25:c25d:dd:dd:dd:8b80/1272c19:dd:c25:c25d:dd:dd:dd:8b81
1942c19:dd:c25:c25d:dd:dd:dd:8b82/1272c19:dd:c25:c25d:dd:dd:dd:8b83
1952c19:dd:c25:c25d:dd:dd:dd:8b84/1272c19:dd:c25:c25d:dd:dd:dd:8b85
1962c19:dd:c25:c25d:dd:dd:dd:8b86/1272c19:dd:c25:c25d:dd:dd:dd:8b87
1972c19:dd:c25:c25d:dd:dd:dd:8b88/1272c19:dd:c25:c25d:dd:dd:dd:8b89
1982c19:dd:c25:c25d:dd:dd:dd:8b8a/1272c19:dd:c25:c25d:dd:dd:dd:8b8b
1992c19:dd:c25:c25d:dd:dd:dd:8b8c/1272c19:dd:c25:c25d:dd:dd:dd:8b8d
2002c19:dd:c25:c25d:dd:dd:dd:8b8e/1272c19:dd:c25:c25d:dd:dd:dd:8b8f
2012c19:dd:c25:c25d:dd:dd:dd:8b90/1272c19:dd:c25:c25d:dd:dd:dd:8b91
2022c19:dd:c25:c25d:dd:dd:dd:8b92/1272c19:dd:c25:c25d:dd:dd:dd:8b93
2032c19:dd:c25:c25d:dd:dd:dd:8b94/1272c19:dd:c25:c25d:dd:dd:dd:8b95
2042c19:dd:c25:c25d:dd:dd:dd:8b96/1272c19:dd:c25:c25d:dd:dd:dd:8b97
2052c19:dd:c25:c25d:dd:dd:dd:8b98/1272c19:dd:c25:c25d:dd:dd:dd:8b99
2062c19:dd:c25:c25d:dd:dd:dd:8b9a/1272c19:dd:c25:c25d:dd:dd:dd:8b9b
2072c19:dd:c25:c25d:dd:dd:dd:8b9c/1272c19:dd:c25:c25d:dd:dd:dd:8b9d
2082c19:dd:c25:c25d:dd:dd:dd:8b9e/1272c19:dd:c25:c25d:dd:dd:dd:8b9f
2092c19:dd:c25:c25d:dd:dd:dd:8ba0/1272c19:dd:c25:c25d:dd:dd:dd:8ba1
2102c19:dd:c25:c25d:dd:dd:dd:8ba2/1272c19:dd:c25:c25d:dd:dd:dd:8ba3
2112c19:dd:c25:c25d:dd:dd:dd:8ba4/1272c19:dd:c25:c25d:dd:dd:dd:8ba5
2122c19:dd:c25:c25d:dd:dd:dd:8ba6/1272c19:dd:c25:c25d:dd:dd:dd:8ba7
2132c19:dd:c25:c25d:dd:dd:dd:8ba8/1272c19:dd:c25:c25d:dd:dd:dd:8ba9
2142c19:dd:c25:c25d:dd:dd:dd:8baa/1272c19:dd:c25:c25d:dd:dd:dd:8bab
2152c19:dd:c25:c25d:dd:dd:dd:8bac/1272c19:dd:c25:c25d:dd:dd:dd:8bad
2162c19:dd:c25:c25d:dd:dd:dd:8bae/1272c19:dd:c25:c25d:dd:dd:dd:8baf
2172c19:dd:c25:c25d:dd:dd:dd:8bb0/1272c19:dd:c25:c25d:dd:dd:dd:8bb1
2182c19:dd:c25:c25d:dd:dd:dd:8bb2/1272c19:dd:c25:c25d:dd:dd:dd:8bb3
2192c19:dd:c25:c25d:dd:dd:dd:8bb4/1272c19:dd:c25:c25d:dd:dd:dd:8bb5
2202c19:dd:c25:c25d:dd:dd:dd:8bb6/1272c19:dd:c25:c25d:dd:dd:dd:8bb7
2212c19:dd:c25:c25d:dd:dd:dd:8bb8/1272c19:dd:c25:c25d:dd:dd:dd:8bb9
2222c19:dd:c25:c25d:dd:dd:dd:8bba/1272c19:dd:c25:c25d:dd:dd:dd:8bbb
2232c19:dd:c25:c25d:dd:dd:dd:8bbc/1272c19:dd:c25:c25d:dd:dd:dd:8bbd
2242c19:dd:c25:c25d:dd:dd:dd:8bbe/1272c19:dd:c25:c25d:dd:dd:dd:8bbf
2252c19:dd:c25:c25d:dd:dd:dd:8bc0/1272c19:dd:c25:c25d:dd:dd:dd:8bc1
2262c19:dd:c25:c25d:dd:dd:dd:8bc2/1272c19:dd:c25:c25d:dd:dd:dd:8bc3
2272c19:dd:c25:c25d:dd:dd:dd:8bc4/1272c19:dd:c25:c25d:dd:dd:dd:8bc5
2282c19:dd:c25:c25d:dd:dd:dd:8bc6/1272c19:dd:c25:c25d:dd:dd:dd:8bc7
2292c19:dd:c25:c25d:dd:dd:dd:8bc8/1272c19:dd:c25:c25d:dd:dd:dd:8bc9
2302c19:dd:c25:c25d:dd:dd:dd:8bca/1272c19:dd:c25:c25d:dd:dd:dd:8bcb
2312c19:dd:c25:c25d:dd:dd:dd:8bcc/1272c19:dd:c25:c25d:dd:dd:dd:8bcd
2322c19:dd:c25:c25d:dd:dd:dd:8bce/1272c19:dd:c25:c25d:dd:dd:dd:8bcf
2332c19:dd:c25:c25d:dd:dd:dd:8bd0/1272c19:dd:c25:c25d:dd:dd:dd:8bd1
2342c19:dd:c25:c25d:dd:dd:dd:8bd2/1272c19:dd:c25:c25d:dd:dd:dd:8bd3
2352c19:dd:c25:c25d:dd:dd:dd:8bd4/1272c19:dd:c25:c25d:dd:dd:dd:8bd5
2362c19:dd:c25:c25d:dd:dd:dd:8bd6/1272c19:dd:c25:c25d:dd:dd:dd:8bd7
2372c19:dd:c25:c25d:dd:dd:dd:8bd8/1272c19:dd:c25:c25d:dd:dd:dd:8bd9
2382c19:dd:c25:c25d:dd:dd:dd:8bda/1272c19:dd:c25:c25d:dd:dd:dd:8bdb
2392c19:dd:c25:c25d:dd:dd:dd:8bdc/1272c19:dd:c25:c25d:dd:dd:dd:8bdd
2402c19:dd:c25:c25d:dd:dd:dd:8bde/1272c19:dd:c25:c25d:dd:dd:dd:8bdf
2412c19:dd:c25:c25d:dd:dd:dd:8be0/1272c19:dd:c25:c25d:dd:dd:dd:8be1
2422c19:dd:c25:c25d:dd:dd:dd:8be2/1272c19:dd:c25:c25d:dd:dd:dd:8be3
2432c19:dd:c25:c25d:dd:dd:dd:8be4/1272c19:dd:c25:c25d:dd:dd:dd:8be5
2442c19:dd:c25:c25d:dd:dd:dd:8be6/1272c19:dd:c25:c25d:dd:dd:dd:8be7
2452c19:dd:c25:c25d:dd:dd:dd:8be8/1272c19:dd:c25:c25d:dd:dd:dd:8be9
2462c19:dd:c25:c25d:dd:dd:dd:8bea/1272c19:dd:c25:c25d:dd:dd:dd:8beb
2472c19:dd:c25:c25d:dd:dd:dd:8bec/1272c19:dd:c25:c25d:dd:dd:dd:8bed
2482c19:dd:c25:c25d:dd:dd:dd:8bee/1272c19:dd:c25:c25d:dd:dd:dd:8bef
2492c19:dd:c25:c25d:dd:dd:dd:8bf0/1272c19:dd:c25:c25d:dd:dd:dd:8bf1
2502c19:dd:c25:c25d:dd:dd:dd:8bf2/1272c19:dd:c25:c25d:dd:dd:dd:8bf3
2512c19:dd:c25:c25d:dd:dd:dd:8bf4/1272c19:dd:c25:c25d:dd:dd:dd:8bf5
2522c19:dd:c25:c25d:dd:dd:dd:8bf6/1272c19:dd:c25:c25d:dd:dd:dd:8bf7
2532c19:dd:c25:c25d:dd:dd:dd:8bf8/1272c19:dd:c25:c25d:dd:dd:dd:8bf9
2542c19:dd:c25:c25d:dd:dd:dd:8bfa/1272c19:dd:c25:c25d:dd:dd:dd:8bfb
2552c19:dd:c25:c25d:dd:dd:dd:8bfc/1272c19:dd:c25:c25d:dd:dd:dd:8bfd
2562c19:dd:c25:c25d:dd:dd:dd:8bfe/1272c19:dd:c25:c25d:dd:dd:dd:8bff

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.