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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/115
Addresses8,192
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:61ba:c000/115
First address
2c19:dd:d9:dd:c25:c25:61ba:c000
Last address
2c19:dd:d9:dd:c25:c25:61ba:dfff
Addresses
8,192
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:61ba:c000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
c.a.b.1.6.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
d.a.b.1.6.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
/115 is not on a 4-bit boundary, so it takes 2 /116 zones.
Split into smaller subnets/127
/116 (2)/117 (4)/118 (8)/119 (16)/120 (32)/124 (512)/127 (4,096)/128 (8,192)

2c19:dd:d9:dd:c25:c25:61ba:c000/115 makes 4,096 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:61ba:c000/1272c19:dd:d9:dd:c25:c25:61ba:c001
22c19:dd:d9:dd:c25:c25:61ba:c002/1272c19:dd:d9:dd:c25:c25:61ba:c003
32c19:dd:d9:dd:c25:c25:61ba:c004/1272c19:dd:d9:dd:c25:c25:61ba:c005
42c19:dd:d9:dd:c25:c25:61ba:c006/1272c19:dd:d9:dd:c25:c25:61ba:c007
52c19:dd:d9:dd:c25:c25:61ba:c008/1272c19:dd:d9:dd:c25:c25:61ba:c009
62c19:dd:d9:dd:c25:c25:61ba:c00a/1272c19:dd:d9:dd:c25:c25:61ba:c00b
72c19:dd:d9:dd:c25:c25:61ba:c00c/1272c19:dd:d9:dd:c25:c25:61ba:c00d
82c19:dd:d9:dd:c25:c25:61ba:c00e/1272c19:dd:d9:dd:c25:c25:61ba:c00f
92c19:dd:d9:dd:c25:c25:61ba:c010/1272c19:dd:d9:dd:c25:c25:61ba:c011
102c19:dd:d9:dd:c25:c25:61ba:c012/1272c19:dd:d9:dd:c25:c25:61ba:c013
112c19:dd:d9:dd:c25:c25:61ba:c014/1272c19:dd:d9:dd:c25:c25:61ba:c015
122c19:dd:d9:dd:c25:c25:61ba:c016/1272c19:dd:d9:dd:c25:c25:61ba:c017
132c19:dd:d9:dd:c25:c25:61ba:c018/1272c19:dd:d9:dd:c25:c25:61ba:c019
142c19:dd:d9:dd:c25:c25:61ba:c01a/1272c19:dd:d9:dd:c25:c25:61ba:c01b
152c19:dd:d9:dd:c25:c25:61ba:c01c/1272c19:dd:d9:dd:c25:c25:61ba:c01d
162c19:dd:d9:dd:c25:c25:61ba:c01e/1272c19:dd:d9:dd:c25:c25:61ba:c01f
172c19:dd:d9:dd:c25:c25:61ba:c020/1272c19:dd:d9:dd:c25:c25:61ba:c021
182c19:dd:d9:dd:c25:c25:61ba:c022/1272c19:dd:d9:dd:c25:c25:61ba:c023
192c19:dd:d9:dd:c25:c25:61ba:c024/1272c19:dd:d9:dd:c25:c25:61ba:c025
202c19:dd:d9:dd:c25:c25:61ba:c026/1272c19:dd:d9:dd:c25:c25:61ba:c027
212c19:dd:d9:dd:c25:c25:61ba:c028/1272c19:dd:d9:dd:c25:c25:61ba:c029
222c19:dd:d9:dd:c25:c25:61ba:c02a/1272c19:dd:d9:dd:c25:c25:61ba:c02b
232c19:dd:d9:dd:c25:c25:61ba:c02c/1272c19:dd:d9:dd:c25:c25:61ba:c02d
242c19:dd:d9:dd:c25:c25:61ba:c02e/1272c19:dd:d9:dd:c25:c25:61ba:c02f
252c19:dd:d9:dd:c25:c25:61ba:c030/1272c19:dd:d9:dd:c25:c25:61ba:c031
262c19:dd:d9:dd:c25:c25:61ba:c032/1272c19:dd:d9:dd:c25:c25:61ba:c033
272c19:dd:d9:dd:c25:c25:61ba:c034/1272c19:dd:d9:dd:c25:c25:61ba:c035
282c19:dd:d9:dd:c25:c25:61ba:c036/1272c19:dd:d9:dd:c25:c25:61ba:c037
292c19:dd:d9:dd:c25:c25:61ba:c038/1272c19:dd:d9:dd:c25:c25:61ba:c039
302c19:dd:d9:dd:c25:c25:61ba:c03a/1272c19:dd:d9:dd:c25:c25:61ba:c03b
312c19:dd:d9:dd:c25:c25:61ba:c03c/1272c19:dd:d9:dd:c25:c25:61ba:c03d
322c19:dd:d9:dd:c25:c25:61ba:c03e/1272c19:dd:d9:dd:c25:c25:61ba:c03f
332c19:dd:d9:dd:c25:c25:61ba:c040/1272c19:dd:d9:dd:c25:c25:61ba:c041
342c19:dd:d9:dd:c25:c25:61ba:c042/1272c19:dd:d9:dd:c25:c25:61ba:c043
352c19:dd:d9:dd:c25:c25:61ba:c044/1272c19:dd:d9:dd:c25:c25:61ba:c045
362c19:dd:d9:dd:c25:c25:61ba:c046/1272c19:dd:d9:dd:c25:c25:61ba:c047
372c19:dd:d9:dd:c25:c25:61ba:c048/1272c19:dd:d9:dd:c25:c25:61ba:c049
382c19:dd:d9:dd:c25:c25:61ba:c04a/1272c19:dd:d9:dd:c25:c25:61ba:c04b
392c19:dd:d9:dd:c25:c25:61ba:c04c/1272c19:dd:d9:dd:c25:c25:61ba:c04d
402c19:dd:d9:dd:c25:c25:61ba:c04e/1272c19:dd:d9:dd:c25:c25:61ba:c04f
412c19:dd:d9:dd:c25:c25:61ba:c050/1272c19:dd:d9:dd:c25:c25:61ba:c051
422c19:dd:d9:dd:c25:c25:61ba:c052/1272c19:dd:d9:dd:c25:c25:61ba:c053
432c19:dd:d9:dd:c25:c25:61ba:c054/1272c19:dd:d9:dd:c25:c25:61ba:c055
442c19:dd:d9:dd:c25:c25:61ba:c056/1272c19:dd:d9:dd:c25:c25:61ba:c057
452c19:dd:d9:dd:c25:c25:61ba:c058/1272c19:dd:d9:dd:c25:c25:61ba:c059
462c19:dd:d9:dd:c25:c25:61ba:c05a/1272c19:dd:d9:dd:c25:c25:61ba:c05b
472c19:dd:d9:dd:c25:c25:61ba:c05c/1272c19:dd:d9:dd:c25:c25:61ba:c05d
482c19:dd:d9:dd:c25:c25:61ba:c05e/1272c19:dd:d9:dd:c25:c25:61ba:c05f
492c19:dd:d9:dd:c25:c25:61ba:c060/1272c19:dd:d9:dd:c25:c25:61ba:c061
502c19:dd:d9:dd:c25:c25:61ba:c062/1272c19:dd:d9:dd:c25:c25:61ba:c063
512c19:dd:d9:dd:c25:c25:61ba:c064/1272c19:dd:d9:dd:c25:c25:61ba:c065
522c19:dd:d9:dd:c25:c25:61ba:c066/1272c19:dd:d9:dd:c25:c25:61ba:c067
532c19:dd:d9:dd:c25:c25:61ba:c068/1272c19:dd:d9:dd:c25:c25:61ba:c069
542c19:dd:d9:dd:c25:c25:61ba:c06a/1272c19:dd:d9:dd:c25:c25:61ba:c06b
552c19:dd:d9:dd:c25:c25:61ba:c06c/1272c19:dd:d9:dd:c25:c25:61ba:c06d
562c19:dd:d9:dd:c25:c25:61ba:c06e/1272c19:dd:d9:dd:c25:c25:61ba:c06f
572c19:dd:d9:dd:c25:c25:61ba:c070/1272c19:dd:d9:dd:c25:c25:61ba:c071
582c19:dd:d9:dd:c25:c25:61ba:c072/1272c19:dd:d9:dd:c25:c25:61ba:c073
592c19:dd:d9:dd:c25:c25:61ba:c074/1272c19:dd:d9:dd:c25:c25:61ba:c075
602c19:dd:d9:dd:c25:c25:61ba:c076/1272c19:dd:d9:dd:c25:c25:61ba:c077
612c19:dd:d9:dd:c25:c25:61ba:c078/1272c19:dd:d9:dd:c25:c25:61ba:c079
622c19:dd:d9:dd:c25:c25:61ba:c07a/1272c19:dd:d9:dd:c25:c25:61ba:c07b
632c19:dd:d9:dd:c25:c25:61ba:c07c/1272c19:dd:d9:dd:c25:c25:61ba:c07d
642c19:dd:d9:dd:c25:c25:61ba:c07e/1272c19:dd:d9:dd:c25:c25:61ba:c07f
652c19:dd:d9:dd:c25:c25:61ba:c080/1272c19:dd:d9:dd:c25:c25:61ba:c081
662c19:dd:d9:dd:c25:c25:61ba:c082/1272c19:dd:d9:dd:c25:c25:61ba:c083
672c19:dd:d9:dd:c25:c25:61ba:c084/1272c19:dd:d9:dd:c25:c25:61ba:c085
682c19:dd:d9:dd:c25:c25:61ba:c086/1272c19:dd:d9:dd:c25:c25:61ba:c087
692c19:dd:d9:dd:c25:c25:61ba:c088/1272c19:dd:d9:dd:c25:c25:61ba:c089
702c19:dd:d9:dd:c25:c25:61ba:c08a/1272c19:dd:d9:dd:c25:c25:61ba:c08b
712c19:dd:d9:dd:c25:c25:61ba:c08c/1272c19:dd:d9:dd:c25:c25:61ba:c08d
722c19:dd:d9:dd:c25:c25:61ba:c08e/1272c19:dd:d9:dd:c25:c25:61ba:c08f
732c19:dd:d9:dd:c25:c25:61ba:c090/1272c19:dd:d9:dd:c25:c25:61ba:c091
742c19:dd:d9:dd:c25:c25:61ba:c092/1272c19:dd:d9:dd:c25:c25:61ba:c093
752c19:dd:d9:dd:c25:c25:61ba:c094/1272c19:dd:d9:dd:c25:c25:61ba:c095
762c19:dd:d9:dd:c25:c25:61ba:c096/1272c19:dd:d9:dd:c25:c25:61ba:c097
772c19:dd:d9:dd:c25:c25:61ba:c098/1272c19:dd:d9:dd:c25:c25:61ba:c099
782c19:dd:d9:dd:c25:c25:61ba:c09a/1272c19:dd:d9:dd:c25:c25:61ba:c09b
792c19:dd:d9:dd:c25:c25:61ba:c09c/1272c19:dd:d9:dd:c25:c25:61ba:c09d
802c19:dd:d9:dd:c25:c25:61ba:c09e/1272c19:dd:d9:dd:c25:c25:61ba:c09f
812c19:dd:d9:dd:c25:c25:61ba:c0a0/1272c19:dd:d9:dd:c25:c25:61ba:c0a1
822c19:dd:d9:dd:c25:c25:61ba:c0a2/1272c19:dd:d9:dd:c25:c25:61ba:c0a3
832c19:dd:d9:dd:c25:c25:61ba:c0a4/1272c19:dd:d9:dd:c25:c25:61ba:c0a5
842c19:dd:d9:dd:c25:c25:61ba:c0a6/1272c19:dd:d9:dd:c25:c25:61ba:c0a7
852c19:dd:d9:dd:c25:c25:61ba:c0a8/1272c19:dd:d9:dd:c25:c25:61ba:c0a9
862c19:dd:d9:dd:c25:c25:61ba:c0aa/1272c19:dd:d9:dd:c25:c25:61ba:c0ab
872c19:dd:d9:dd:c25:c25:61ba:c0ac/1272c19:dd:d9:dd:c25:c25:61ba:c0ad
882c19:dd:d9:dd:c25:c25:61ba:c0ae/1272c19:dd:d9:dd:c25:c25:61ba:c0af
892c19:dd:d9:dd:c25:c25:61ba:c0b0/1272c19:dd:d9:dd:c25:c25:61ba:c0b1
902c19:dd:d9:dd:c25:c25:61ba:c0b2/1272c19:dd:d9:dd:c25:c25:61ba:c0b3
912c19:dd:d9:dd:c25:c25:61ba:c0b4/1272c19:dd:d9:dd:c25:c25:61ba:c0b5
922c19:dd:d9:dd:c25:c25:61ba:c0b6/1272c19:dd:d9:dd:c25:c25:61ba:c0b7
932c19:dd:d9:dd:c25:c25:61ba:c0b8/1272c19:dd:d9:dd:c25:c25:61ba:c0b9
942c19:dd:d9:dd:c25:c25:61ba:c0ba/1272c19:dd:d9:dd:c25:c25:61ba:c0bb
952c19:dd:d9:dd:c25:c25:61ba:c0bc/1272c19:dd:d9:dd:c25:c25:61ba:c0bd
962c19:dd:d9:dd:c25:c25:61ba:c0be/1272c19:dd:d9:dd:c25:c25:61ba:c0bf
972c19:dd:d9:dd:c25:c25:61ba:c0c0/1272c19:dd:d9:dd:c25:c25:61ba:c0c1
982c19:dd:d9:dd:c25:c25:61ba:c0c2/1272c19:dd:d9:dd:c25:c25:61ba:c0c3
992c19:dd:d9:dd:c25:c25:61ba:c0c4/1272c19:dd:d9:dd:c25:c25:61ba:c0c5
1002c19:dd:d9:dd:c25:c25:61ba:c0c6/1272c19:dd:d9:dd:c25:c25:61ba:c0c7
1012c19:dd:d9:dd:c25:c25:61ba:c0c8/1272c19:dd:d9:dd:c25:c25:61ba:c0c9
1022c19:dd:d9:dd:c25:c25:61ba:c0ca/1272c19:dd:d9:dd:c25:c25:61ba:c0cb
1032c19:dd:d9:dd:c25:c25:61ba:c0cc/1272c19:dd:d9:dd:c25:c25:61ba:c0cd
1042c19:dd:d9:dd:c25:c25:61ba:c0ce/1272c19:dd:d9:dd:c25:c25:61ba:c0cf
1052c19:dd:d9:dd:c25:c25:61ba:c0d0/1272c19:dd:d9:dd:c25:c25:61ba:c0d1
1062c19:dd:d9:dd:c25:c25:61ba:c0d2/1272c19:dd:d9:dd:c25:c25:61ba:c0d3
1072c19:dd:d9:dd:c25:c25:61ba:c0d4/1272c19:dd:d9:dd:c25:c25:61ba:c0d5
1082c19:dd:d9:dd:c25:c25:61ba:c0d6/1272c19:dd:d9:dd:c25:c25:61ba:c0d7
1092c19:dd:d9:dd:c25:c25:61ba:c0d8/1272c19:dd:d9:dd:c25:c25:61ba:c0d9
1102c19:dd:d9:dd:c25:c25:61ba:c0da/1272c19:dd:d9:dd:c25:c25:61ba:c0db
1112c19:dd:d9:dd:c25:c25:61ba:c0dc/1272c19:dd:d9:dd:c25:c25:61ba:c0dd
1122c19:dd:d9:dd:c25:c25:61ba:c0de/1272c19:dd:d9:dd:c25:c25:61ba:c0df
1132c19:dd:d9:dd:c25:c25:61ba:c0e0/1272c19:dd:d9:dd:c25:c25:61ba:c0e1
1142c19:dd:d9:dd:c25:c25:61ba:c0e2/1272c19:dd:d9:dd:c25:c25:61ba:c0e3
1152c19:dd:d9:dd:c25:c25:61ba:c0e4/1272c19:dd:d9:dd:c25:c25:61ba:c0e5
1162c19:dd:d9:dd:c25:c25:61ba:c0e6/1272c19:dd:d9:dd:c25:c25:61ba:c0e7
1172c19:dd:d9:dd:c25:c25:61ba:c0e8/1272c19:dd:d9:dd:c25:c25:61ba:c0e9
1182c19:dd:d9:dd:c25:c25:61ba:c0ea/1272c19:dd:d9:dd:c25:c25:61ba:c0eb
1192c19:dd:d9:dd:c25:c25:61ba:c0ec/1272c19:dd:d9:dd:c25:c25:61ba:c0ed
1202c19:dd:d9:dd:c25:c25:61ba:c0ee/1272c19:dd:d9:dd:c25:c25:61ba:c0ef
1212c19:dd:d9:dd:c25:c25:61ba:c0f0/1272c19:dd:d9:dd:c25:c25:61ba:c0f1
1222c19:dd:d9:dd:c25:c25:61ba:c0f2/1272c19:dd:d9:dd:c25:c25:61ba:c0f3
1232c19:dd:d9:dd:c25:c25:61ba:c0f4/1272c19:dd:d9:dd:c25:c25:61ba:c0f5
1242c19:dd:d9:dd:c25:c25:61ba:c0f6/1272c19:dd:d9:dd:c25:c25:61ba:c0f7
1252c19:dd:d9:dd:c25:c25:61ba:c0f8/1272c19:dd:d9:dd:c25:c25:61ba:c0f9
1262c19:dd:d9:dd:c25:c25:61ba:c0fa/1272c19:dd:d9:dd:c25:c25:61ba:c0fb
1272c19:dd:d9:dd:c25:c25:61ba:c0fc/1272c19:dd:d9:dd:c25:c25:61ba:c0fd
1282c19:dd:d9:dd:c25:c25:61ba:c0fe/1272c19:dd:d9:dd:c25:c25:61ba:c0ff
1292c19:dd:d9:dd:c25:c25:61ba:c100/1272c19:dd:d9:dd:c25:c25:61ba:c101
1302c19:dd:d9:dd:c25:c25:61ba:c102/1272c19:dd:d9:dd:c25:c25:61ba:c103
1312c19:dd:d9:dd:c25:c25:61ba:c104/1272c19:dd:d9:dd:c25:c25:61ba:c105
1322c19:dd:d9:dd:c25:c25:61ba:c106/1272c19:dd:d9:dd:c25:c25:61ba:c107
1332c19:dd:d9:dd:c25:c25:61ba:c108/1272c19:dd:d9:dd:c25:c25:61ba:c109
1342c19:dd:d9:dd:c25:c25:61ba:c10a/1272c19:dd:d9:dd:c25:c25:61ba:c10b
1352c19:dd:d9:dd:c25:c25:61ba:c10c/1272c19:dd:d9:dd:c25:c25:61ba:c10d
1362c19:dd:d9:dd:c25:c25:61ba:c10e/1272c19:dd:d9:dd:c25:c25:61ba:c10f
1372c19:dd:d9:dd:c25:c25:61ba:c110/1272c19:dd:d9:dd:c25:c25:61ba:c111
1382c19:dd:d9:dd:c25:c25:61ba:c112/1272c19:dd:d9:dd:c25:c25:61ba:c113
1392c19:dd:d9:dd:c25:c25:61ba:c114/1272c19:dd:d9:dd:c25:c25:61ba:c115
1402c19:dd:d9:dd:c25:c25:61ba:c116/1272c19:dd:d9:dd:c25:c25:61ba:c117
1412c19:dd:d9:dd:c25:c25:61ba:c118/1272c19:dd:d9:dd:c25:c25:61ba:c119
1422c19:dd:d9:dd:c25:c25:61ba:c11a/1272c19:dd:d9:dd:c25:c25:61ba:c11b
1432c19:dd:d9:dd:c25:c25:61ba:c11c/1272c19:dd:d9:dd:c25:c25:61ba:c11d
1442c19:dd:d9:dd:c25:c25:61ba:c11e/1272c19:dd:d9:dd:c25:c25:61ba:c11f
1452c19:dd:d9:dd:c25:c25:61ba:c120/1272c19:dd:d9:dd:c25:c25:61ba:c121
1462c19:dd:d9:dd:c25:c25:61ba:c122/1272c19:dd:d9:dd:c25:c25:61ba:c123
1472c19:dd:d9:dd:c25:c25:61ba:c124/1272c19:dd:d9:dd:c25:c25:61ba:c125
1482c19:dd:d9:dd:c25:c25:61ba:c126/1272c19:dd:d9:dd:c25:c25:61ba:c127
1492c19:dd:d9:dd:c25:c25:61ba:c128/1272c19:dd:d9:dd:c25:c25:61ba:c129
1502c19:dd:d9:dd:c25:c25:61ba:c12a/1272c19:dd:d9:dd:c25:c25:61ba:c12b
1512c19:dd:d9:dd:c25:c25:61ba:c12c/1272c19:dd:d9:dd:c25:c25:61ba:c12d
1522c19:dd:d9:dd:c25:c25:61ba:c12e/1272c19:dd:d9:dd:c25:c25:61ba:c12f
1532c19:dd:d9:dd:c25:c25:61ba:c130/1272c19:dd:d9:dd:c25:c25:61ba:c131
1542c19:dd:d9:dd:c25:c25:61ba:c132/1272c19:dd:d9:dd:c25:c25:61ba:c133
1552c19:dd:d9:dd:c25:c25:61ba:c134/1272c19:dd:d9:dd:c25:c25:61ba:c135
1562c19:dd:d9:dd:c25:c25:61ba:c136/1272c19:dd:d9:dd:c25:c25:61ba:c137
1572c19:dd:d9:dd:c25:c25:61ba:c138/1272c19:dd:d9:dd:c25:c25:61ba:c139
1582c19:dd:d9:dd:c25:c25:61ba:c13a/1272c19:dd:d9:dd:c25:c25:61ba:c13b
1592c19:dd:d9:dd:c25:c25:61ba:c13c/1272c19:dd:d9:dd:c25:c25:61ba:c13d
1602c19:dd:d9:dd:c25:c25:61ba:c13e/1272c19:dd:d9:dd:c25:c25:61ba:c13f
1612c19:dd:d9:dd:c25:c25:61ba:c140/1272c19:dd:d9:dd:c25:c25:61ba:c141
1622c19:dd:d9:dd:c25:c25:61ba:c142/1272c19:dd:d9:dd:c25:c25:61ba:c143
1632c19:dd:d9:dd:c25:c25:61ba:c144/1272c19:dd:d9:dd:c25:c25:61ba:c145
1642c19:dd:d9:dd:c25:c25:61ba:c146/1272c19:dd:d9:dd:c25:c25:61ba:c147
1652c19:dd:d9:dd:c25:c25:61ba:c148/1272c19:dd:d9:dd:c25:c25:61ba:c149
1662c19:dd:d9:dd:c25:c25:61ba:c14a/1272c19:dd:d9:dd:c25:c25:61ba:c14b
1672c19:dd:d9:dd:c25:c25:61ba:c14c/1272c19:dd:d9:dd:c25:c25:61ba:c14d
1682c19:dd:d9:dd:c25:c25:61ba:c14e/1272c19:dd:d9:dd:c25:c25:61ba:c14f
1692c19:dd:d9:dd:c25:c25:61ba:c150/1272c19:dd:d9:dd:c25:c25:61ba:c151
1702c19:dd:d9:dd:c25:c25:61ba:c152/1272c19:dd:d9:dd:c25:c25:61ba:c153
1712c19:dd:d9:dd:c25:c25:61ba:c154/1272c19:dd:d9:dd:c25:c25:61ba:c155
1722c19:dd:d9:dd:c25:c25:61ba:c156/1272c19:dd:d9:dd:c25:c25:61ba:c157
1732c19:dd:d9:dd:c25:c25:61ba:c158/1272c19:dd:d9:dd:c25:c25:61ba:c159
1742c19:dd:d9:dd:c25:c25:61ba:c15a/1272c19:dd:d9:dd:c25:c25:61ba:c15b
1752c19:dd:d9:dd:c25:c25:61ba:c15c/1272c19:dd:d9:dd:c25:c25:61ba:c15d
1762c19:dd:d9:dd:c25:c25:61ba:c15e/1272c19:dd:d9:dd:c25:c25:61ba:c15f
1772c19:dd:d9:dd:c25:c25:61ba:c160/1272c19:dd:d9:dd:c25:c25:61ba:c161
1782c19:dd:d9:dd:c25:c25:61ba:c162/1272c19:dd:d9:dd:c25:c25:61ba:c163
1792c19:dd:d9:dd:c25:c25:61ba:c164/1272c19:dd:d9:dd:c25:c25:61ba:c165
1802c19:dd:d9:dd:c25:c25:61ba:c166/1272c19:dd:d9:dd:c25:c25:61ba:c167
1812c19:dd:d9:dd:c25:c25:61ba:c168/1272c19:dd:d9:dd:c25:c25:61ba:c169
1822c19:dd:d9:dd:c25:c25:61ba:c16a/1272c19:dd:d9:dd:c25:c25:61ba:c16b
1832c19:dd:d9:dd:c25:c25:61ba:c16c/1272c19:dd:d9:dd:c25:c25:61ba:c16d
1842c19:dd:d9:dd:c25:c25:61ba:c16e/1272c19:dd:d9:dd:c25:c25:61ba:c16f
1852c19:dd:d9:dd:c25:c25:61ba:c170/1272c19:dd:d9:dd:c25:c25:61ba:c171
1862c19:dd:d9:dd:c25:c25:61ba:c172/1272c19:dd:d9:dd:c25:c25:61ba:c173
1872c19:dd:d9:dd:c25:c25:61ba:c174/1272c19:dd:d9:dd:c25:c25:61ba:c175
1882c19:dd:d9:dd:c25:c25:61ba:c176/1272c19:dd:d9:dd:c25:c25:61ba:c177
1892c19:dd:d9:dd:c25:c25:61ba:c178/1272c19:dd:d9:dd:c25:c25:61ba:c179
1902c19:dd:d9:dd:c25:c25:61ba:c17a/1272c19:dd:d9:dd:c25:c25:61ba:c17b
1912c19:dd:d9:dd:c25:c25:61ba:c17c/1272c19:dd:d9:dd:c25:c25:61ba:c17d
1922c19:dd:d9:dd:c25:c25:61ba:c17e/1272c19:dd:d9:dd:c25:c25:61ba:c17f
1932c19:dd:d9:dd:c25:c25:61ba:c180/1272c19:dd:d9:dd:c25:c25:61ba:c181
1942c19:dd:d9:dd:c25:c25:61ba:c182/1272c19:dd:d9:dd:c25:c25:61ba:c183
1952c19:dd:d9:dd:c25:c25:61ba:c184/1272c19:dd:d9:dd:c25:c25:61ba:c185
1962c19:dd:d9:dd:c25:c25:61ba:c186/1272c19:dd:d9:dd:c25:c25:61ba:c187
1972c19:dd:d9:dd:c25:c25:61ba:c188/1272c19:dd:d9:dd:c25:c25:61ba:c189
1982c19:dd:d9:dd:c25:c25:61ba:c18a/1272c19:dd:d9:dd:c25:c25:61ba:c18b
1992c19:dd:d9:dd:c25:c25:61ba:c18c/1272c19:dd:d9:dd:c25:c25:61ba:c18d
2002c19:dd:d9:dd:c25:c25:61ba:c18e/1272c19:dd:d9:dd:c25:c25:61ba:c18f
2012c19:dd:d9:dd:c25:c25:61ba:c190/1272c19:dd:d9:dd:c25:c25:61ba:c191
2022c19:dd:d9:dd:c25:c25:61ba:c192/1272c19:dd:d9:dd:c25:c25:61ba:c193
2032c19:dd:d9:dd:c25:c25:61ba:c194/1272c19:dd:d9:dd:c25:c25:61ba:c195
2042c19:dd:d9:dd:c25:c25:61ba:c196/1272c19:dd:d9:dd:c25:c25:61ba:c197
2052c19:dd:d9:dd:c25:c25:61ba:c198/1272c19:dd:d9:dd:c25:c25:61ba:c199
2062c19:dd:d9:dd:c25:c25:61ba:c19a/1272c19:dd:d9:dd:c25:c25:61ba:c19b
2072c19:dd:d9:dd:c25:c25:61ba:c19c/1272c19:dd:d9:dd:c25:c25:61ba:c19d
2082c19:dd:d9:dd:c25:c25:61ba:c19e/1272c19:dd:d9:dd:c25:c25:61ba:c19f
2092c19:dd:d9:dd:c25:c25:61ba:c1a0/1272c19:dd:d9:dd:c25:c25:61ba:c1a1
2102c19:dd:d9:dd:c25:c25:61ba:c1a2/1272c19:dd:d9:dd:c25:c25:61ba:c1a3
2112c19:dd:d9:dd:c25:c25:61ba:c1a4/1272c19:dd:d9:dd:c25:c25:61ba:c1a5
2122c19:dd:d9:dd:c25:c25:61ba:c1a6/1272c19:dd:d9:dd:c25:c25:61ba:c1a7
2132c19:dd:d9:dd:c25:c25:61ba:c1a8/1272c19:dd:d9:dd:c25:c25:61ba:c1a9
2142c19:dd:d9:dd:c25:c25:61ba:c1aa/1272c19:dd:d9:dd:c25:c25:61ba:c1ab
2152c19:dd:d9:dd:c25:c25:61ba:c1ac/1272c19:dd:d9:dd:c25:c25:61ba:c1ad
2162c19:dd:d9:dd:c25:c25:61ba:c1ae/1272c19:dd:d9:dd:c25:c25:61ba:c1af
2172c19:dd:d9:dd:c25:c25:61ba:c1b0/1272c19:dd:d9:dd:c25:c25:61ba:c1b1
2182c19:dd:d9:dd:c25:c25:61ba:c1b2/1272c19:dd:d9:dd:c25:c25:61ba:c1b3
2192c19:dd:d9:dd:c25:c25:61ba:c1b4/1272c19:dd:d9:dd:c25:c25:61ba:c1b5
2202c19:dd:d9:dd:c25:c25:61ba:c1b6/1272c19:dd:d9:dd:c25:c25:61ba:c1b7
2212c19:dd:d9:dd:c25:c25:61ba:c1b8/1272c19:dd:d9:dd:c25:c25:61ba:c1b9
2222c19:dd:d9:dd:c25:c25:61ba:c1ba/1272c19:dd:d9:dd:c25:c25:61ba:c1bb
2232c19:dd:d9:dd:c25:c25:61ba:c1bc/1272c19:dd:d9:dd:c25:c25:61ba:c1bd
2242c19:dd:d9:dd:c25:c25:61ba:c1be/1272c19:dd:d9:dd:c25:c25:61ba:c1bf
2252c19:dd:d9:dd:c25:c25:61ba:c1c0/1272c19:dd:d9:dd:c25:c25:61ba:c1c1
2262c19:dd:d9:dd:c25:c25:61ba:c1c2/1272c19:dd:d9:dd:c25:c25:61ba:c1c3
2272c19:dd:d9:dd:c25:c25:61ba:c1c4/1272c19:dd:d9:dd:c25:c25:61ba:c1c5
2282c19:dd:d9:dd:c25:c25:61ba:c1c6/1272c19:dd:d9:dd:c25:c25:61ba:c1c7
2292c19:dd:d9:dd:c25:c25:61ba:c1c8/1272c19:dd:d9:dd:c25:c25:61ba:c1c9
2302c19:dd:d9:dd:c25:c25:61ba:c1ca/1272c19:dd:d9:dd:c25:c25:61ba:c1cb
2312c19:dd:d9:dd:c25:c25:61ba:c1cc/1272c19:dd:d9:dd:c25:c25:61ba:c1cd
2322c19:dd:d9:dd:c25:c25:61ba:c1ce/1272c19:dd:d9:dd:c25:c25:61ba:c1cf
2332c19:dd:d9:dd:c25:c25:61ba:c1d0/1272c19:dd:d9:dd:c25:c25:61ba:c1d1
2342c19:dd:d9:dd:c25:c25:61ba:c1d2/1272c19:dd:d9:dd:c25:c25:61ba:c1d3
2352c19:dd:d9:dd:c25:c25:61ba:c1d4/1272c19:dd:d9:dd:c25:c25:61ba:c1d5
2362c19:dd:d9:dd:c25:c25:61ba:c1d6/1272c19:dd:d9:dd:c25:c25:61ba:c1d7
2372c19:dd:d9:dd:c25:c25:61ba:c1d8/1272c19:dd:d9:dd:c25:c25:61ba:c1d9
2382c19:dd:d9:dd:c25:c25:61ba:c1da/1272c19:dd:d9:dd:c25:c25:61ba:c1db
2392c19:dd:d9:dd:c25:c25:61ba:c1dc/1272c19:dd:d9:dd:c25:c25:61ba:c1dd
2402c19:dd:d9:dd:c25:c25:61ba:c1de/1272c19:dd:d9:dd:c25:c25:61ba:c1df
2412c19:dd:d9:dd:c25:c25:61ba:c1e0/1272c19:dd:d9:dd:c25:c25:61ba:c1e1
2422c19:dd:d9:dd:c25:c25:61ba:c1e2/1272c19:dd:d9:dd:c25:c25:61ba:c1e3
2432c19:dd:d9:dd:c25:c25:61ba:c1e4/1272c19:dd:d9:dd:c25:c25:61ba:c1e5
2442c19:dd:d9:dd:c25:c25:61ba:c1e6/1272c19:dd:d9:dd:c25:c25:61ba:c1e7
2452c19:dd:d9:dd:c25:c25:61ba:c1e8/1272c19:dd:d9:dd:c25:c25:61ba:c1e9
2462c19:dd:d9:dd:c25:c25:61ba:c1ea/1272c19:dd:d9:dd:c25:c25:61ba:c1eb
2472c19:dd:d9:dd:c25:c25:61ba:c1ec/1272c19:dd:d9:dd:c25:c25:61ba:c1ed
2482c19:dd:d9:dd:c25:c25:61ba:c1ee/1272c19:dd:d9:dd:c25:c25:61ba:c1ef
2492c19:dd:d9:dd:c25:c25:61ba:c1f0/1272c19:dd:d9:dd:c25:c25:61ba:c1f1
2502c19:dd:d9:dd:c25:c25:61ba:c1f2/1272c19:dd:d9:dd:c25:c25:61ba:c1f3
2512c19:dd:d9:dd:c25:c25:61ba:c1f4/1272c19:dd:d9:dd:c25:c25:61ba:c1f5
2522c19:dd:d9:dd:c25:c25:61ba:c1f6/1272c19:dd:d9:dd:c25:c25:61ba:c1f7
2532c19:dd:d9:dd:c25:c25:61ba:c1f8/1272c19:dd:d9:dd:c25:c25:61ba:c1f9
2542c19:dd:d9:dd:c25:c25:61ba:c1fa/1272c19:dd:d9:dd:c25:c25:61ba:c1fb
2552c19:dd:d9:dd:c25:c25:61ba:c1fc/1272c19:dd:d9:dd:c25:c25:61ba:c1fd
2562c19:dd:d9:dd:c25:c25:61ba:c1fe/1272c19:dd:d9:dd:c25:c25:61ba:c1ff

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.