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

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

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.