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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:d9:dd:c25:c25:94de:aa00/119
First address
2c19:dd:d9:dd:c25:c25:94de:aa00
Last address
2c19:dd:d9:dd:c25:c25:94de:abff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:aa00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
a.a.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
b.a.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
/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:d9:dd:c25:c25:94de:aa00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:aa00/1272c19:dd:d9:dd:c25:c25:94de:aa01
22c19:dd:d9:dd:c25:c25:94de:aa02/1272c19:dd:d9:dd:c25:c25:94de:aa03
32c19:dd:d9:dd:c25:c25:94de:aa04/1272c19:dd:d9:dd:c25:c25:94de:aa05
42c19:dd:d9:dd:c25:c25:94de:aa06/1272c19:dd:d9:dd:c25:c25:94de:aa07
52c19:dd:d9:dd:c25:c25:94de:aa08/1272c19:dd:d9:dd:c25:c25:94de:aa09
62c19:dd:d9:dd:c25:c25:94de:aa0a/1272c19:dd:d9:dd:c25:c25:94de:aa0b
72c19:dd:d9:dd:c25:c25:94de:aa0c/1272c19:dd:d9:dd:c25:c25:94de:aa0d
82c19:dd:d9:dd:c25:c25:94de:aa0e/1272c19:dd:d9:dd:c25:c25:94de:aa0f
92c19:dd:d9:dd:c25:c25:94de:aa10/1272c19:dd:d9:dd:c25:c25:94de:aa11
102c19:dd:d9:dd:c25:c25:94de:aa12/1272c19:dd:d9:dd:c25:c25:94de:aa13
112c19:dd:d9:dd:c25:c25:94de:aa14/1272c19:dd:d9:dd:c25:c25:94de:aa15
122c19:dd:d9:dd:c25:c25:94de:aa16/1272c19:dd:d9:dd:c25:c25:94de:aa17
132c19:dd:d9:dd:c25:c25:94de:aa18/1272c19:dd:d9:dd:c25:c25:94de:aa19
142c19:dd:d9:dd:c25:c25:94de:aa1a/1272c19:dd:d9:dd:c25:c25:94de:aa1b
152c19:dd:d9:dd:c25:c25:94de:aa1c/1272c19:dd:d9:dd:c25:c25:94de:aa1d
162c19:dd:d9:dd:c25:c25:94de:aa1e/1272c19:dd:d9:dd:c25:c25:94de:aa1f
172c19:dd:d9:dd:c25:c25:94de:aa20/1272c19:dd:d9:dd:c25:c25:94de:aa21
182c19:dd:d9:dd:c25:c25:94de:aa22/1272c19:dd:d9:dd:c25:c25:94de:aa23
192c19:dd:d9:dd:c25:c25:94de:aa24/1272c19:dd:d9:dd:c25:c25:94de:aa25
202c19:dd:d9:dd:c25:c25:94de:aa26/1272c19:dd:d9:dd:c25:c25:94de:aa27
212c19:dd:d9:dd:c25:c25:94de:aa28/1272c19:dd:d9:dd:c25:c25:94de:aa29
222c19:dd:d9:dd:c25:c25:94de:aa2a/1272c19:dd:d9:dd:c25:c25:94de:aa2b
232c19:dd:d9:dd:c25:c25:94de:aa2c/1272c19:dd:d9:dd:c25:c25:94de:aa2d
242c19:dd:d9:dd:c25:c25:94de:aa2e/1272c19:dd:d9:dd:c25:c25:94de:aa2f
252c19:dd:d9:dd:c25:c25:94de:aa30/1272c19:dd:d9:dd:c25:c25:94de:aa31
262c19:dd:d9:dd:c25:c25:94de:aa32/1272c19:dd:d9:dd:c25:c25:94de:aa33
272c19:dd:d9:dd:c25:c25:94de:aa34/1272c19:dd:d9:dd:c25:c25:94de:aa35
282c19:dd:d9:dd:c25:c25:94de:aa36/1272c19:dd:d9:dd:c25:c25:94de:aa37
292c19:dd:d9:dd:c25:c25:94de:aa38/1272c19:dd:d9:dd:c25:c25:94de:aa39
302c19:dd:d9:dd:c25:c25:94de:aa3a/1272c19:dd:d9:dd:c25:c25:94de:aa3b
312c19:dd:d9:dd:c25:c25:94de:aa3c/1272c19:dd:d9:dd:c25:c25:94de:aa3d
322c19:dd:d9:dd:c25:c25:94de:aa3e/1272c19:dd:d9:dd:c25:c25:94de:aa3f
332c19:dd:d9:dd:c25:c25:94de:aa40/1272c19:dd:d9:dd:c25:c25:94de:aa41
342c19:dd:d9:dd:c25:c25:94de:aa42/1272c19:dd:d9:dd:c25:c25:94de:aa43
352c19:dd:d9:dd:c25:c25:94de:aa44/1272c19:dd:d9:dd:c25:c25:94de:aa45
362c19:dd:d9:dd:c25:c25:94de:aa46/1272c19:dd:d9:dd:c25:c25:94de:aa47
372c19:dd:d9:dd:c25:c25:94de:aa48/1272c19:dd:d9:dd:c25:c25:94de:aa49
382c19:dd:d9:dd:c25:c25:94de:aa4a/1272c19:dd:d9:dd:c25:c25:94de:aa4b
392c19:dd:d9:dd:c25:c25:94de:aa4c/1272c19:dd:d9:dd:c25:c25:94de:aa4d
402c19:dd:d9:dd:c25:c25:94de:aa4e/1272c19:dd:d9:dd:c25:c25:94de:aa4f
412c19:dd:d9:dd:c25:c25:94de:aa50/1272c19:dd:d9:dd:c25:c25:94de:aa51
422c19:dd:d9:dd:c25:c25:94de:aa52/1272c19:dd:d9:dd:c25:c25:94de:aa53
432c19:dd:d9:dd:c25:c25:94de:aa54/1272c19:dd:d9:dd:c25:c25:94de:aa55
442c19:dd:d9:dd:c25:c25:94de:aa56/1272c19:dd:d9:dd:c25:c25:94de:aa57
452c19:dd:d9:dd:c25:c25:94de:aa58/1272c19:dd:d9:dd:c25:c25:94de:aa59
462c19:dd:d9:dd:c25:c25:94de:aa5a/1272c19:dd:d9:dd:c25:c25:94de:aa5b
472c19:dd:d9:dd:c25:c25:94de:aa5c/1272c19:dd:d9:dd:c25:c25:94de:aa5d
482c19:dd:d9:dd:c25:c25:94de:aa5e/1272c19:dd:d9:dd:c25:c25:94de:aa5f
492c19:dd:d9:dd:c25:c25:94de:aa60/1272c19:dd:d9:dd:c25:c25:94de:aa61
502c19:dd:d9:dd:c25:c25:94de:aa62/1272c19:dd:d9:dd:c25:c25:94de:aa63
512c19:dd:d9:dd:c25:c25:94de:aa64/1272c19:dd:d9:dd:c25:c25:94de:aa65
522c19:dd:d9:dd:c25:c25:94de:aa66/1272c19:dd:d9:dd:c25:c25:94de:aa67
532c19:dd:d9:dd:c25:c25:94de:aa68/1272c19:dd:d9:dd:c25:c25:94de:aa69
542c19:dd:d9:dd:c25:c25:94de:aa6a/1272c19:dd:d9:dd:c25:c25:94de:aa6b
552c19:dd:d9:dd:c25:c25:94de:aa6c/1272c19:dd:d9:dd:c25:c25:94de:aa6d
562c19:dd:d9:dd:c25:c25:94de:aa6e/1272c19:dd:d9:dd:c25:c25:94de:aa6f
572c19:dd:d9:dd:c25:c25:94de:aa70/1272c19:dd:d9:dd:c25:c25:94de:aa71
582c19:dd:d9:dd:c25:c25:94de:aa72/1272c19:dd:d9:dd:c25:c25:94de:aa73
592c19:dd:d9:dd:c25:c25:94de:aa74/1272c19:dd:d9:dd:c25:c25:94de:aa75
602c19:dd:d9:dd:c25:c25:94de:aa76/1272c19:dd:d9:dd:c25:c25:94de:aa77
612c19:dd:d9:dd:c25:c25:94de:aa78/1272c19:dd:d9:dd:c25:c25:94de:aa79
622c19:dd:d9:dd:c25:c25:94de:aa7a/1272c19:dd:d9:dd:c25:c25:94de:aa7b
632c19:dd:d9:dd:c25:c25:94de:aa7c/1272c19:dd:d9:dd:c25:c25:94de:aa7d
642c19:dd:d9:dd:c25:c25:94de:aa7e/1272c19:dd:d9:dd:c25:c25:94de:aa7f
652c19:dd:d9:dd:c25:c25:94de:aa80/1272c19:dd:d9:dd:c25:c25:94de:aa81
662c19:dd:d9:dd:c25:c25:94de:aa82/1272c19:dd:d9:dd:c25:c25:94de:aa83
672c19:dd:d9:dd:c25:c25:94de:aa84/1272c19:dd:d9:dd:c25:c25:94de:aa85
682c19:dd:d9:dd:c25:c25:94de:aa86/1272c19:dd:d9:dd:c25:c25:94de:aa87
692c19:dd:d9:dd:c25:c25:94de:aa88/1272c19:dd:d9:dd:c25:c25:94de:aa89
702c19:dd:d9:dd:c25:c25:94de:aa8a/1272c19:dd:d9:dd:c25:c25:94de:aa8b
712c19:dd:d9:dd:c25:c25:94de:aa8c/1272c19:dd:d9:dd:c25:c25:94de:aa8d
722c19:dd:d9:dd:c25:c25:94de:aa8e/1272c19:dd:d9:dd:c25:c25:94de:aa8f
732c19:dd:d9:dd:c25:c25:94de:aa90/1272c19:dd:d9:dd:c25:c25:94de:aa91
742c19:dd:d9:dd:c25:c25:94de:aa92/1272c19:dd:d9:dd:c25:c25:94de:aa93
752c19:dd:d9:dd:c25:c25:94de:aa94/1272c19:dd:d9:dd:c25:c25:94de:aa95
762c19:dd:d9:dd:c25:c25:94de:aa96/1272c19:dd:d9:dd:c25:c25:94de:aa97
772c19:dd:d9:dd:c25:c25:94de:aa98/1272c19:dd:d9:dd:c25:c25:94de:aa99
782c19:dd:d9:dd:c25:c25:94de:aa9a/1272c19:dd:d9:dd:c25:c25:94de:aa9b
792c19:dd:d9:dd:c25:c25:94de:aa9c/1272c19:dd:d9:dd:c25:c25:94de:aa9d
802c19:dd:d9:dd:c25:c25:94de:aa9e/1272c19:dd:d9:dd:c25:c25:94de:aa9f
812c19:dd:d9:dd:c25:c25:94de:aaa0/1272c19:dd:d9:dd:c25:c25:94de:aaa1
822c19:dd:d9:dd:c25:c25:94de:aaa2/1272c19:dd:d9:dd:c25:c25:94de:aaa3
832c19:dd:d9:dd:c25:c25:94de:aaa4/1272c19:dd:d9:dd:c25:c25:94de:aaa5
842c19:dd:d9:dd:c25:c25:94de:aaa6/1272c19:dd:d9:dd:c25:c25:94de:aaa7
852c19:dd:d9:dd:c25:c25:94de:aaa8/1272c19:dd:d9:dd:c25:c25:94de:aaa9
862c19:dd:d9:dd:c25:c25:94de:aaaa/1272c19:dd:d9:dd:c25:c25:94de:aaab
872c19:dd:d9:dd:c25:c25:94de:aaac/1272c19:dd:d9:dd:c25:c25:94de:aaad
882c19:dd:d9:dd:c25:c25:94de:aaae/1272c19:dd:d9:dd:c25:c25:94de:aaaf
892c19:dd:d9:dd:c25:c25:94de:aab0/1272c19:dd:d9:dd:c25:c25:94de:aab1
902c19:dd:d9:dd:c25:c25:94de:aab2/1272c19:dd:d9:dd:c25:c25:94de:aab3
912c19:dd:d9:dd:c25:c25:94de:aab4/1272c19:dd:d9:dd:c25:c25:94de:aab5
922c19:dd:d9:dd:c25:c25:94de:aab6/1272c19:dd:d9:dd:c25:c25:94de:aab7
932c19:dd:d9:dd:c25:c25:94de:aab8/1272c19:dd:d9:dd:c25:c25:94de:aab9
942c19:dd:d9:dd:c25:c25:94de:aaba/1272c19:dd:d9:dd:c25:c25:94de:aabb
952c19:dd:d9:dd:c25:c25:94de:aabc/1272c19:dd:d9:dd:c25:c25:94de:aabd
962c19:dd:d9:dd:c25:c25:94de:aabe/1272c19:dd:d9:dd:c25:c25:94de:aabf
972c19:dd:d9:dd:c25:c25:94de:aac0/1272c19:dd:d9:dd:c25:c25:94de:aac1
982c19:dd:d9:dd:c25:c25:94de:aac2/1272c19:dd:d9:dd:c25:c25:94de:aac3
992c19:dd:d9:dd:c25:c25:94de:aac4/1272c19:dd:d9:dd:c25:c25:94de:aac5
1002c19:dd:d9:dd:c25:c25:94de:aac6/1272c19:dd:d9:dd:c25:c25:94de:aac7
1012c19:dd:d9:dd:c25:c25:94de:aac8/1272c19:dd:d9:dd:c25:c25:94de:aac9
1022c19:dd:d9:dd:c25:c25:94de:aaca/1272c19:dd:d9:dd:c25:c25:94de:aacb
1032c19:dd:d9:dd:c25:c25:94de:aacc/1272c19:dd:d9:dd:c25:c25:94de:aacd
1042c19:dd:d9:dd:c25:c25:94de:aace/1272c19:dd:d9:dd:c25:c25:94de:aacf
1052c19:dd:d9:dd:c25:c25:94de:aad0/1272c19:dd:d9:dd:c25:c25:94de:aad1
1062c19:dd:d9:dd:c25:c25:94de:aad2/1272c19:dd:d9:dd:c25:c25:94de:aad3
1072c19:dd:d9:dd:c25:c25:94de:aad4/1272c19:dd:d9:dd:c25:c25:94de:aad5
1082c19:dd:d9:dd:c25:c25:94de:aad6/1272c19:dd:d9:dd:c25:c25:94de:aad7
1092c19:dd:d9:dd:c25:c25:94de:aad8/1272c19:dd:d9:dd:c25:c25:94de:aad9
1102c19:dd:d9:dd:c25:c25:94de:aada/1272c19:dd:d9:dd:c25:c25:94de:aadb
1112c19:dd:d9:dd:c25:c25:94de:aadc/1272c19:dd:d9:dd:c25:c25:94de:aadd
1122c19:dd:d9:dd:c25:c25:94de:aade/1272c19:dd:d9:dd:c25:c25:94de:aadf
1132c19:dd:d9:dd:c25:c25:94de:aae0/1272c19:dd:d9:dd:c25:c25:94de:aae1
1142c19:dd:d9:dd:c25:c25:94de:aae2/1272c19:dd:d9:dd:c25:c25:94de:aae3
1152c19:dd:d9:dd:c25:c25:94de:aae4/1272c19:dd:d9:dd:c25:c25:94de:aae5
1162c19:dd:d9:dd:c25:c25:94de:aae6/1272c19:dd:d9:dd:c25:c25:94de:aae7
1172c19:dd:d9:dd:c25:c25:94de:aae8/1272c19:dd:d9:dd:c25:c25:94de:aae9
1182c19:dd:d9:dd:c25:c25:94de:aaea/1272c19:dd:d9:dd:c25:c25:94de:aaeb
1192c19:dd:d9:dd:c25:c25:94de:aaec/1272c19:dd:d9:dd:c25:c25:94de:aaed
1202c19:dd:d9:dd:c25:c25:94de:aaee/1272c19:dd:d9:dd:c25:c25:94de:aaef
1212c19:dd:d9:dd:c25:c25:94de:aaf0/1272c19:dd:d9:dd:c25:c25:94de:aaf1
1222c19:dd:d9:dd:c25:c25:94de:aaf2/1272c19:dd:d9:dd:c25:c25:94de:aaf3
1232c19:dd:d9:dd:c25:c25:94de:aaf4/1272c19:dd:d9:dd:c25:c25:94de:aaf5
1242c19:dd:d9:dd:c25:c25:94de:aaf6/1272c19:dd:d9:dd:c25:c25:94de:aaf7
1252c19:dd:d9:dd:c25:c25:94de:aaf8/1272c19:dd:d9:dd:c25:c25:94de:aaf9
1262c19:dd:d9:dd:c25:c25:94de:aafa/1272c19:dd:d9:dd:c25:c25:94de:aafb
1272c19:dd:d9:dd:c25:c25:94de:aafc/1272c19:dd:d9:dd:c25:c25:94de:aafd
1282c19:dd:d9:dd:c25:c25:94de:aafe/1272c19:dd:d9:dd:c25:c25:94de:aaff
1292c19:dd:d9:dd:c25:c25:94de:ab00/1272c19:dd:d9:dd:c25:c25:94de:ab01
1302c19:dd:d9:dd:c25:c25:94de:ab02/1272c19:dd:d9:dd:c25:c25:94de:ab03
1312c19:dd:d9:dd:c25:c25:94de:ab04/1272c19:dd:d9:dd:c25:c25:94de:ab05
1322c19:dd:d9:dd:c25:c25:94de:ab06/1272c19:dd:d9:dd:c25:c25:94de:ab07
1332c19:dd:d9:dd:c25:c25:94de:ab08/1272c19:dd:d9:dd:c25:c25:94de:ab09
1342c19:dd:d9:dd:c25:c25:94de:ab0a/1272c19:dd:d9:dd:c25:c25:94de:ab0b
1352c19:dd:d9:dd:c25:c25:94de:ab0c/1272c19:dd:d9:dd:c25:c25:94de:ab0d
1362c19:dd:d9:dd:c25:c25:94de:ab0e/1272c19:dd:d9:dd:c25:c25:94de:ab0f
1372c19:dd:d9:dd:c25:c25:94de:ab10/1272c19:dd:d9:dd:c25:c25:94de:ab11
1382c19:dd:d9:dd:c25:c25:94de:ab12/1272c19:dd:d9:dd:c25:c25:94de:ab13
1392c19:dd:d9:dd:c25:c25:94de:ab14/1272c19:dd:d9:dd:c25:c25:94de:ab15
1402c19:dd:d9:dd:c25:c25:94de:ab16/1272c19:dd:d9:dd:c25:c25:94de:ab17
1412c19:dd:d9:dd:c25:c25:94de:ab18/1272c19:dd:d9:dd:c25:c25:94de:ab19
1422c19:dd:d9:dd:c25:c25:94de:ab1a/1272c19:dd:d9:dd:c25:c25:94de:ab1b
1432c19:dd:d9:dd:c25:c25:94de:ab1c/1272c19:dd:d9:dd:c25:c25:94de:ab1d
1442c19:dd:d9:dd:c25:c25:94de:ab1e/1272c19:dd:d9:dd:c25:c25:94de:ab1f
1452c19:dd:d9:dd:c25:c25:94de:ab20/1272c19:dd:d9:dd:c25:c25:94de:ab21
1462c19:dd:d9:dd:c25:c25:94de:ab22/1272c19:dd:d9:dd:c25:c25:94de:ab23
1472c19:dd:d9:dd:c25:c25:94de:ab24/1272c19:dd:d9:dd:c25:c25:94de:ab25
1482c19:dd:d9:dd:c25:c25:94de:ab26/1272c19:dd:d9:dd:c25:c25:94de:ab27
1492c19:dd:d9:dd:c25:c25:94de:ab28/1272c19:dd:d9:dd:c25:c25:94de:ab29
1502c19:dd:d9:dd:c25:c25:94de:ab2a/1272c19:dd:d9:dd:c25:c25:94de:ab2b
1512c19:dd:d9:dd:c25:c25:94de:ab2c/1272c19:dd:d9:dd:c25:c25:94de:ab2d
1522c19:dd:d9:dd:c25:c25:94de:ab2e/1272c19:dd:d9:dd:c25:c25:94de:ab2f
1532c19:dd:d9:dd:c25:c25:94de:ab30/1272c19:dd:d9:dd:c25:c25:94de:ab31
1542c19:dd:d9:dd:c25:c25:94de:ab32/1272c19:dd:d9:dd:c25:c25:94de:ab33
1552c19:dd:d9:dd:c25:c25:94de:ab34/1272c19:dd:d9:dd:c25:c25:94de:ab35
1562c19:dd:d9:dd:c25:c25:94de:ab36/1272c19:dd:d9:dd:c25:c25:94de:ab37
1572c19:dd:d9:dd:c25:c25:94de:ab38/1272c19:dd:d9:dd:c25:c25:94de:ab39
1582c19:dd:d9:dd:c25:c25:94de:ab3a/1272c19:dd:d9:dd:c25:c25:94de:ab3b
1592c19:dd:d9:dd:c25:c25:94de:ab3c/1272c19:dd:d9:dd:c25:c25:94de:ab3d
1602c19:dd:d9:dd:c25:c25:94de:ab3e/1272c19:dd:d9:dd:c25:c25:94de:ab3f
1612c19:dd:d9:dd:c25:c25:94de:ab40/1272c19:dd:d9:dd:c25:c25:94de:ab41
1622c19:dd:d9:dd:c25:c25:94de:ab42/1272c19:dd:d9:dd:c25:c25:94de:ab43
1632c19:dd:d9:dd:c25:c25:94de:ab44/1272c19:dd:d9:dd:c25:c25:94de:ab45
1642c19:dd:d9:dd:c25:c25:94de:ab46/1272c19:dd:d9:dd:c25:c25:94de:ab47
1652c19:dd:d9:dd:c25:c25:94de:ab48/1272c19:dd:d9:dd:c25:c25:94de:ab49
1662c19:dd:d9:dd:c25:c25:94de:ab4a/1272c19:dd:d9:dd:c25:c25:94de:ab4b
1672c19:dd:d9:dd:c25:c25:94de:ab4c/1272c19:dd:d9:dd:c25:c25:94de:ab4d
1682c19:dd:d9:dd:c25:c25:94de:ab4e/1272c19:dd:d9:dd:c25:c25:94de:ab4f
1692c19:dd:d9:dd:c25:c25:94de:ab50/1272c19:dd:d9:dd:c25:c25:94de:ab51
1702c19:dd:d9:dd:c25:c25:94de:ab52/1272c19:dd:d9:dd:c25:c25:94de:ab53
1712c19:dd:d9:dd:c25:c25:94de:ab54/1272c19:dd:d9:dd:c25:c25:94de:ab55
1722c19:dd:d9:dd:c25:c25:94de:ab56/1272c19:dd:d9:dd:c25:c25:94de:ab57
1732c19:dd:d9:dd:c25:c25:94de:ab58/1272c19:dd:d9:dd:c25:c25:94de:ab59
1742c19:dd:d9:dd:c25:c25:94de:ab5a/1272c19:dd:d9:dd:c25:c25:94de:ab5b
1752c19:dd:d9:dd:c25:c25:94de:ab5c/1272c19:dd:d9:dd:c25:c25:94de:ab5d
1762c19:dd:d9:dd:c25:c25:94de:ab5e/1272c19:dd:d9:dd:c25:c25:94de:ab5f
1772c19:dd:d9:dd:c25:c25:94de:ab60/1272c19:dd:d9:dd:c25:c25:94de:ab61
1782c19:dd:d9:dd:c25:c25:94de:ab62/1272c19:dd:d9:dd:c25:c25:94de:ab63
1792c19:dd:d9:dd:c25:c25:94de:ab64/1272c19:dd:d9:dd:c25:c25:94de:ab65
1802c19:dd:d9:dd:c25:c25:94de:ab66/1272c19:dd:d9:dd:c25:c25:94de:ab67
1812c19:dd:d9:dd:c25:c25:94de:ab68/1272c19:dd:d9:dd:c25:c25:94de:ab69
1822c19:dd:d9:dd:c25:c25:94de:ab6a/1272c19:dd:d9:dd:c25:c25:94de:ab6b
1832c19:dd:d9:dd:c25:c25:94de:ab6c/1272c19:dd:d9:dd:c25:c25:94de:ab6d
1842c19:dd:d9:dd:c25:c25:94de:ab6e/1272c19:dd:d9:dd:c25:c25:94de:ab6f
1852c19:dd:d9:dd:c25:c25:94de:ab70/1272c19:dd:d9:dd:c25:c25:94de:ab71
1862c19:dd:d9:dd:c25:c25:94de:ab72/1272c19:dd:d9:dd:c25:c25:94de:ab73
1872c19:dd:d9:dd:c25:c25:94de:ab74/1272c19:dd:d9:dd:c25:c25:94de:ab75
1882c19:dd:d9:dd:c25:c25:94de:ab76/1272c19:dd:d9:dd:c25:c25:94de:ab77
1892c19:dd:d9:dd:c25:c25:94de:ab78/1272c19:dd:d9:dd:c25:c25:94de:ab79
1902c19:dd:d9:dd:c25:c25:94de:ab7a/1272c19:dd:d9:dd:c25:c25:94de:ab7b
1912c19:dd:d9:dd:c25:c25:94de:ab7c/1272c19:dd:d9:dd:c25:c25:94de:ab7d
1922c19:dd:d9:dd:c25:c25:94de:ab7e/1272c19:dd:d9:dd:c25:c25:94de:ab7f
1932c19:dd:d9:dd:c25:c25:94de:ab80/1272c19:dd:d9:dd:c25:c25:94de:ab81
1942c19:dd:d9:dd:c25:c25:94de:ab82/1272c19:dd:d9:dd:c25:c25:94de:ab83
1952c19:dd:d9:dd:c25:c25:94de:ab84/1272c19:dd:d9:dd:c25:c25:94de:ab85
1962c19:dd:d9:dd:c25:c25:94de:ab86/1272c19:dd:d9:dd:c25:c25:94de:ab87
1972c19:dd:d9:dd:c25:c25:94de:ab88/1272c19:dd:d9:dd:c25:c25:94de:ab89
1982c19:dd:d9:dd:c25:c25:94de:ab8a/1272c19:dd:d9:dd:c25:c25:94de:ab8b
1992c19:dd:d9:dd:c25:c25:94de:ab8c/1272c19:dd:d9:dd:c25:c25:94de:ab8d
2002c19:dd:d9:dd:c25:c25:94de:ab8e/1272c19:dd:d9:dd:c25:c25:94de:ab8f
2012c19:dd:d9:dd:c25:c25:94de:ab90/1272c19:dd:d9:dd:c25:c25:94de:ab91
2022c19:dd:d9:dd:c25:c25:94de:ab92/1272c19:dd:d9:dd:c25:c25:94de:ab93
2032c19:dd:d9:dd:c25:c25:94de:ab94/1272c19:dd:d9:dd:c25:c25:94de:ab95
2042c19:dd:d9:dd:c25:c25:94de:ab96/1272c19:dd:d9:dd:c25:c25:94de:ab97
2052c19:dd:d9:dd:c25:c25:94de:ab98/1272c19:dd:d9:dd:c25:c25:94de:ab99
2062c19:dd:d9:dd:c25:c25:94de:ab9a/1272c19:dd:d9:dd:c25:c25:94de:ab9b
2072c19:dd:d9:dd:c25:c25:94de:ab9c/1272c19:dd:d9:dd:c25:c25:94de:ab9d
2082c19:dd:d9:dd:c25:c25:94de:ab9e/1272c19:dd:d9:dd:c25:c25:94de:ab9f
2092c19:dd:d9:dd:c25:c25:94de:aba0/1272c19:dd:d9:dd:c25:c25:94de:aba1
2102c19:dd:d9:dd:c25:c25:94de:aba2/1272c19:dd:d9:dd:c25:c25:94de:aba3
2112c19:dd:d9:dd:c25:c25:94de:aba4/1272c19:dd:d9:dd:c25:c25:94de:aba5
2122c19:dd:d9:dd:c25:c25:94de:aba6/1272c19:dd:d9:dd:c25:c25:94de:aba7
2132c19:dd:d9:dd:c25:c25:94de:aba8/1272c19:dd:d9:dd:c25:c25:94de:aba9
2142c19:dd:d9:dd:c25:c25:94de:abaa/1272c19:dd:d9:dd:c25:c25:94de:abab
2152c19:dd:d9:dd:c25:c25:94de:abac/1272c19:dd:d9:dd:c25:c25:94de:abad
2162c19:dd:d9:dd:c25:c25:94de:abae/1272c19:dd:d9:dd:c25:c25:94de:abaf
2172c19:dd:d9:dd:c25:c25:94de:abb0/1272c19:dd:d9:dd:c25:c25:94de:abb1
2182c19:dd:d9:dd:c25:c25:94de:abb2/1272c19:dd:d9:dd:c25:c25:94de:abb3
2192c19:dd:d9:dd:c25:c25:94de:abb4/1272c19:dd:d9:dd:c25:c25:94de:abb5
2202c19:dd:d9:dd:c25:c25:94de:abb6/1272c19:dd:d9:dd:c25:c25:94de:abb7
2212c19:dd:d9:dd:c25:c25:94de:abb8/1272c19:dd:d9:dd:c25:c25:94de:abb9
2222c19:dd:d9:dd:c25:c25:94de:abba/1272c19:dd:d9:dd:c25:c25:94de:abbb
2232c19:dd:d9:dd:c25:c25:94de:abbc/1272c19:dd:d9:dd:c25:c25:94de:abbd
2242c19:dd:d9:dd:c25:c25:94de:abbe/1272c19:dd:d9:dd:c25:c25:94de:abbf
2252c19:dd:d9:dd:c25:c25:94de:abc0/1272c19:dd:d9:dd:c25:c25:94de:abc1
2262c19:dd:d9:dd:c25:c25:94de:abc2/1272c19:dd:d9:dd:c25:c25:94de:abc3
2272c19:dd:d9:dd:c25:c25:94de:abc4/1272c19:dd:d9:dd:c25:c25:94de:abc5
2282c19:dd:d9:dd:c25:c25:94de:abc6/1272c19:dd:d9:dd:c25:c25:94de:abc7
2292c19:dd:d9:dd:c25:c25:94de:abc8/1272c19:dd:d9:dd:c25:c25:94de:abc9
2302c19:dd:d9:dd:c25:c25:94de:abca/1272c19:dd:d9:dd:c25:c25:94de:abcb
2312c19:dd:d9:dd:c25:c25:94de:abcc/1272c19:dd:d9:dd:c25:c25:94de:abcd
2322c19:dd:d9:dd:c25:c25:94de:abce/1272c19:dd:d9:dd:c25:c25:94de:abcf
2332c19:dd:d9:dd:c25:c25:94de:abd0/1272c19:dd:d9:dd:c25:c25:94de:abd1
2342c19:dd:d9:dd:c25:c25:94de:abd2/1272c19:dd:d9:dd:c25:c25:94de:abd3
2352c19:dd:d9:dd:c25:c25:94de:abd4/1272c19:dd:d9:dd:c25:c25:94de:abd5
2362c19:dd:d9:dd:c25:c25:94de:abd6/1272c19:dd:d9:dd:c25:c25:94de:abd7
2372c19:dd:d9:dd:c25:c25:94de:abd8/1272c19:dd:d9:dd:c25:c25:94de:abd9
2382c19:dd:d9:dd:c25:c25:94de:abda/1272c19:dd:d9:dd:c25:c25:94de:abdb
2392c19:dd:d9:dd:c25:c25:94de:abdc/1272c19:dd:d9:dd:c25:c25:94de:abdd
2402c19:dd:d9:dd:c25:c25:94de:abde/1272c19:dd:d9:dd:c25:c25:94de:abdf
2412c19:dd:d9:dd:c25:c25:94de:abe0/1272c19:dd:d9:dd:c25:c25:94de:abe1
2422c19:dd:d9:dd:c25:c25:94de:abe2/1272c19:dd:d9:dd:c25:c25:94de:abe3
2432c19:dd:d9:dd:c25:c25:94de:abe4/1272c19:dd:d9:dd:c25:c25:94de:abe5
2442c19:dd:d9:dd:c25:c25:94de:abe6/1272c19:dd:d9:dd:c25:c25:94de:abe7
2452c19:dd:d9:dd:c25:c25:94de:abe8/1272c19:dd:d9:dd:c25:c25:94de:abe9
2462c19:dd:d9:dd:c25:c25:94de:abea/1272c19:dd:d9:dd:c25:c25:94de:abeb
2472c19:dd:d9:dd:c25:c25:94de:abec/1272c19:dd:d9:dd:c25:c25:94de:abed
2482c19:dd:d9:dd:c25:c25:94de:abee/1272c19:dd:d9:dd:c25:c25:94de:abef
2492c19:dd:d9:dd:c25:c25:94de:abf0/1272c19:dd:d9:dd:c25:c25:94de:abf1
2502c19:dd:d9:dd:c25:c25:94de:abf2/1272c19:dd:d9:dd:c25:c25:94de:abf3
2512c19:dd:d9:dd:c25:c25:94de:abf4/1272c19:dd:d9:dd:c25:c25:94de:abf5
2522c19:dd:d9:dd:c25:c25:94de:abf6/1272c19:dd:d9:dd:c25:c25:94de:abf7
2532c19:dd:d9:dd:c25:c25:94de:abf8/1272c19:dd:d9:dd:c25:c25:94de:abf9
2542c19:dd:d9:dd:c25:c25:94de:abfa/1272c19:dd:d9:dd:c25:c25:94de:abfb
2552c19:dd:d9:dd:c25:c25:94de:abfc/1272c19:dd:d9:dd:c25:c25:94de:abfd
2562c19:dd:d9:dd:c25:c25:94de:abfe/1272c19:dd:d9:dd:c25:c25:94de:abff

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.