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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/116
Addresses4,096
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:a005:f000/116
First address
2c19:dd:d9:dd:c25:c25:a005:f000
Last address
2c19:dd:d9:dd:c25:c25:a005:ffff
Addresses
4,096
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:a005:f000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
f.5.0.0.a.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
Split into smaller subnets/127
/117 (2)/118 (4)/119 (8)/120 (16)/124 (256)/127 (2,048)/128 (4,096)

2c19:dd:d9:dd:c25:c25:a005:f000/116 makes 2,048 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:a005:f000/1272c19:dd:d9:dd:c25:c25:a005:f001
22c19:dd:d9:dd:c25:c25:a005:f002/1272c19:dd:d9:dd:c25:c25:a005:f003
32c19:dd:d9:dd:c25:c25:a005:f004/1272c19:dd:d9:dd:c25:c25:a005:f005
42c19:dd:d9:dd:c25:c25:a005:f006/1272c19:dd:d9:dd:c25:c25:a005:f007
52c19:dd:d9:dd:c25:c25:a005:f008/1272c19:dd:d9:dd:c25:c25:a005:f009
62c19:dd:d9:dd:c25:c25:a005:f00a/1272c19:dd:d9:dd:c25:c25:a005:f00b
72c19:dd:d9:dd:c25:c25:a005:f00c/1272c19:dd:d9:dd:c25:c25:a005:f00d
82c19:dd:d9:dd:c25:c25:a005:f00e/1272c19:dd:d9:dd:c25:c25:a005:f00f
92c19:dd:d9:dd:c25:c25:a005:f010/1272c19:dd:d9:dd:c25:c25:a005:f011
102c19:dd:d9:dd:c25:c25:a005:f012/1272c19:dd:d9:dd:c25:c25:a005:f013
112c19:dd:d9:dd:c25:c25:a005:f014/1272c19:dd:d9:dd:c25:c25:a005:f015
122c19:dd:d9:dd:c25:c25:a005:f016/1272c19:dd:d9:dd:c25:c25:a005:f017
132c19:dd:d9:dd:c25:c25:a005:f018/1272c19:dd:d9:dd:c25:c25:a005:f019
142c19:dd:d9:dd:c25:c25:a005:f01a/1272c19:dd:d9:dd:c25:c25:a005:f01b
152c19:dd:d9:dd:c25:c25:a005:f01c/1272c19:dd:d9:dd:c25:c25:a005:f01d
162c19:dd:d9:dd:c25:c25:a005:f01e/1272c19:dd:d9:dd:c25:c25:a005:f01f
172c19:dd:d9:dd:c25:c25:a005:f020/1272c19:dd:d9:dd:c25:c25:a005:f021
182c19:dd:d9:dd:c25:c25:a005:f022/1272c19:dd:d9:dd:c25:c25:a005:f023
192c19:dd:d9:dd:c25:c25:a005:f024/1272c19:dd:d9:dd:c25:c25:a005:f025
202c19:dd:d9:dd:c25:c25:a005:f026/1272c19:dd:d9:dd:c25:c25:a005:f027
212c19:dd:d9:dd:c25:c25:a005:f028/1272c19:dd:d9:dd:c25:c25:a005:f029
222c19:dd:d9:dd:c25:c25:a005:f02a/1272c19:dd:d9:dd:c25:c25:a005:f02b
232c19:dd:d9:dd:c25:c25:a005:f02c/1272c19:dd:d9:dd:c25:c25:a005:f02d
242c19:dd:d9:dd:c25:c25:a005:f02e/1272c19:dd:d9:dd:c25:c25:a005:f02f
252c19:dd:d9:dd:c25:c25:a005:f030/1272c19:dd:d9:dd:c25:c25:a005:f031
262c19:dd:d9:dd:c25:c25:a005:f032/1272c19:dd:d9:dd:c25:c25:a005:f033
272c19:dd:d9:dd:c25:c25:a005:f034/1272c19:dd:d9:dd:c25:c25:a005:f035
282c19:dd:d9:dd:c25:c25:a005:f036/1272c19:dd:d9:dd:c25:c25:a005:f037
292c19:dd:d9:dd:c25:c25:a005:f038/1272c19:dd:d9:dd:c25:c25:a005:f039
302c19:dd:d9:dd:c25:c25:a005:f03a/1272c19:dd:d9:dd:c25:c25:a005:f03b
312c19:dd:d9:dd:c25:c25:a005:f03c/1272c19:dd:d9:dd:c25:c25:a005:f03d
322c19:dd:d9:dd:c25:c25:a005:f03e/1272c19:dd:d9:dd:c25:c25:a005:f03f
332c19:dd:d9:dd:c25:c25:a005:f040/1272c19:dd:d9:dd:c25:c25:a005:f041
342c19:dd:d9:dd:c25:c25:a005:f042/1272c19:dd:d9:dd:c25:c25:a005:f043
352c19:dd:d9:dd:c25:c25:a005:f044/1272c19:dd:d9:dd:c25:c25:a005:f045
362c19:dd:d9:dd:c25:c25:a005:f046/1272c19:dd:d9:dd:c25:c25:a005:f047
372c19:dd:d9:dd:c25:c25:a005:f048/1272c19:dd:d9:dd:c25:c25:a005:f049
382c19:dd:d9:dd:c25:c25:a005:f04a/1272c19:dd:d9:dd:c25:c25:a005:f04b
392c19:dd:d9:dd:c25:c25:a005:f04c/1272c19:dd:d9:dd:c25:c25:a005:f04d
402c19:dd:d9:dd:c25:c25:a005:f04e/1272c19:dd:d9:dd:c25:c25:a005:f04f
412c19:dd:d9:dd:c25:c25:a005:f050/1272c19:dd:d9:dd:c25:c25:a005:f051
422c19:dd:d9:dd:c25:c25:a005:f052/1272c19:dd:d9:dd:c25:c25:a005:f053
432c19:dd:d9:dd:c25:c25:a005:f054/1272c19:dd:d9:dd:c25:c25:a005:f055
442c19:dd:d9:dd:c25:c25:a005:f056/1272c19:dd:d9:dd:c25:c25:a005:f057
452c19:dd:d9:dd:c25:c25:a005:f058/1272c19:dd:d9:dd:c25:c25:a005:f059
462c19:dd:d9:dd:c25:c25:a005:f05a/1272c19:dd:d9:dd:c25:c25:a005:f05b
472c19:dd:d9:dd:c25:c25:a005:f05c/1272c19:dd:d9:dd:c25:c25:a005:f05d
482c19:dd:d9:dd:c25:c25:a005:f05e/1272c19:dd:d9:dd:c25:c25:a005:f05f
492c19:dd:d9:dd:c25:c25:a005:f060/1272c19:dd:d9:dd:c25:c25:a005:f061
502c19:dd:d9:dd:c25:c25:a005:f062/1272c19:dd:d9:dd:c25:c25:a005:f063
512c19:dd:d9:dd:c25:c25:a005:f064/1272c19:dd:d9:dd:c25:c25:a005:f065
522c19:dd:d9:dd:c25:c25:a005:f066/1272c19:dd:d9:dd:c25:c25:a005:f067
532c19:dd:d9:dd:c25:c25:a005:f068/1272c19:dd:d9:dd:c25:c25:a005:f069
542c19:dd:d9:dd:c25:c25:a005:f06a/1272c19:dd:d9:dd:c25:c25:a005:f06b
552c19:dd:d9:dd:c25:c25:a005:f06c/1272c19:dd:d9:dd:c25:c25:a005:f06d
562c19:dd:d9:dd:c25:c25:a005:f06e/1272c19:dd:d9:dd:c25:c25:a005:f06f
572c19:dd:d9:dd:c25:c25:a005:f070/1272c19:dd:d9:dd:c25:c25:a005:f071
582c19:dd:d9:dd:c25:c25:a005:f072/1272c19:dd:d9:dd:c25:c25:a005:f073
592c19:dd:d9:dd:c25:c25:a005:f074/1272c19:dd:d9:dd:c25:c25:a005:f075
602c19:dd:d9:dd:c25:c25:a005:f076/1272c19:dd:d9:dd:c25:c25:a005:f077
612c19:dd:d9:dd:c25:c25:a005:f078/1272c19:dd:d9:dd:c25:c25:a005:f079
622c19:dd:d9:dd:c25:c25:a005:f07a/1272c19:dd:d9:dd:c25:c25:a005:f07b
632c19:dd:d9:dd:c25:c25:a005:f07c/1272c19:dd:d9:dd:c25:c25:a005:f07d
642c19:dd:d9:dd:c25:c25:a005:f07e/1272c19:dd:d9:dd:c25:c25:a005:f07f
652c19:dd:d9:dd:c25:c25:a005:f080/1272c19:dd:d9:dd:c25:c25:a005:f081
662c19:dd:d9:dd:c25:c25:a005:f082/1272c19:dd:d9:dd:c25:c25:a005:f083
672c19:dd:d9:dd:c25:c25:a005:f084/1272c19:dd:d9:dd:c25:c25:a005:f085
682c19:dd:d9:dd:c25:c25:a005:f086/1272c19:dd:d9:dd:c25:c25:a005:f087
692c19:dd:d9:dd:c25:c25:a005:f088/1272c19:dd:d9:dd:c25:c25:a005:f089
702c19:dd:d9:dd:c25:c25:a005:f08a/1272c19:dd:d9:dd:c25:c25:a005:f08b
712c19:dd:d9:dd:c25:c25:a005:f08c/1272c19:dd:d9:dd:c25:c25:a005:f08d
722c19:dd:d9:dd:c25:c25:a005:f08e/1272c19:dd:d9:dd:c25:c25:a005:f08f
732c19:dd:d9:dd:c25:c25:a005:f090/1272c19:dd:d9:dd:c25:c25:a005:f091
742c19:dd:d9:dd:c25:c25:a005:f092/1272c19:dd:d9:dd:c25:c25:a005:f093
752c19:dd:d9:dd:c25:c25:a005:f094/1272c19:dd:d9:dd:c25:c25:a005:f095
762c19:dd:d9:dd:c25:c25:a005:f096/1272c19:dd:d9:dd:c25:c25:a005:f097
772c19:dd:d9:dd:c25:c25:a005:f098/1272c19:dd:d9:dd:c25:c25:a005:f099
782c19:dd:d9:dd:c25:c25:a005:f09a/1272c19:dd:d9:dd:c25:c25:a005:f09b
792c19:dd:d9:dd:c25:c25:a005:f09c/1272c19:dd:d9:dd:c25:c25:a005:f09d
802c19:dd:d9:dd:c25:c25:a005:f09e/1272c19:dd:d9:dd:c25:c25:a005:f09f
812c19:dd:d9:dd:c25:c25:a005:f0a0/1272c19:dd:d9:dd:c25:c25:a005:f0a1
822c19:dd:d9:dd:c25:c25:a005:f0a2/1272c19:dd:d9:dd:c25:c25:a005:f0a3
832c19:dd:d9:dd:c25:c25:a005:f0a4/1272c19:dd:d9:dd:c25:c25:a005:f0a5
842c19:dd:d9:dd:c25:c25:a005:f0a6/1272c19:dd:d9:dd:c25:c25:a005:f0a7
852c19:dd:d9:dd:c25:c25:a005:f0a8/1272c19:dd:d9:dd:c25:c25:a005:f0a9
862c19:dd:d9:dd:c25:c25:a005:f0aa/1272c19:dd:d9:dd:c25:c25:a005:f0ab
872c19:dd:d9:dd:c25:c25:a005:f0ac/1272c19:dd:d9:dd:c25:c25:a005:f0ad
882c19:dd:d9:dd:c25:c25:a005:f0ae/1272c19:dd:d9:dd:c25:c25:a005:f0af
892c19:dd:d9:dd:c25:c25:a005:f0b0/1272c19:dd:d9:dd:c25:c25:a005:f0b1
902c19:dd:d9:dd:c25:c25:a005:f0b2/1272c19:dd:d9:dd:c25:c25:a005:f0b3
912c19:dd:d9:dd:c25:c25:a005:f0b4/1272c19:dd:d9:dd:c25:c25:a005:f0b5
922c19:dd:d9:dd:c25:c25:a005:f0b6/1272c19:dd:d9:dd:c25:c25:a005:f0b7
932c19:dd:d9:dd:c25:c25:a005:f0b8/1272c19:dd:d9:dd:c25:c25:a005:f0b9
942c19:dd:d9:dd:c25:c25:a005:f0ba/1272c19:dd:d9:dd:c25:c25:a005:f0bb
952c19:dd:d9:dd:c25:c25:a005:f0bc/1272c19:dd:d9:dd:c25:c25:a005:f0bd
962c19:dd:d9:dd:c25:c25:a005:f0be/1272c19:dd:d9:dd:c25:c25:a005:f0bf
972c19:dd:d9:dd:c25:c25:a005:f0c0/1272c19:dd:d9:dd:c25:c25:a005:f0c1
982c19:dd:d9:dd:c25:c25:a005:f0c2/1272c19:dd:d9:dd:c25:c25:a005:f0c3
992c19:dd:d9:dd:c25:c25:a005:f0c4/1272c19:dd:d9:dd:c25:c25:a005:f0c5
1002c19:dd:d9:dd:c25:c25:a005:f0c6/1272c19:dd:d9:dd:c25:c25:a005:f0c7
1012c19:dd:d9:dd:c25:c25:a005:f0c8/1272c19:dd:d9:dd:c25:c25:a005:f0c9
1022c19:dd:d9:dd:c25:c25:a005:f0ca/1272c19:dd:d9:dd:c25:c25:a005:f0cb
1032c19:dd:d9:dd:c25:c25:a005:f0cc/1272c19:dd:d9:dd:c25:c25:a005:f0cd
1042c19:dd:d9:dd:c25:c25:a005:f0ce/1272c19:dd:d9:dd:c25:c25:a005:f0cf
1052c19:dd:d9:dd:c25:c25:a005:f0d0/1272c19:dd:d9:dd:c25:c25:a005:f0d1
1062c19:dd:d9:dd:c25:c25:a005:f0d2/1272c19:dd:d9:dd:c25:c25:a005:f0d3
1072c19:dd:d9:dd:c25:c25:a005:f0d4/1272c19:dd:d9:dd:c25:c25:a005:f0d5
1082c19:dd:d9:dd:c25:c25:a005:f0d6/1272c19:dd:d9:dd:c25:c25:a005:f0d7
1092c19:dd:d9:dd:c25:c25:a005:f0d8/1272c19:dd:d9:dd:c25:c25:a005:f0d9
1102c19:dd:d9:dd:c25:c25:a005:f0da/1272c19:dd:d9:dd:c25:c25:a005:f0db
1112c19:dd:d9:dd:c25:c25:a005:f0dc/1272c19:dd:d9:dd:c25:c25:a005:f0dd
1122c19:dd:d9:dd:c25:c25:a005:f0de/1272c19:dd:d9:dd:c25:c25:a005:f0df
1132c19:dd:d9:dd:c25:c25:a005:f0e0/1272c19:dd:d9:dd:c25:c25:a005:f0e1
1142c19:dd:d9:dd:c25:c25:a005:f0e2/1272c19:dd:d9:dd:c25:c25:a005:f0e3
1152c19:dd:d9:dd:c25:c25:a005:f0e4/1272c19:dd:d9:dd:c25:c25:a005:f0e5
1162c19:dd:d9:dd:c25:c25:a005:f0e6/1272c19:dd:d9:dd:c25:c25:a005:f0e7
1172c19:dd:d9:dd:c25:c25:a005:f0e8/1272c19:dd:d9:dd:c25:c25:a005:f0e9
1182c19:dd:d9:dd:c25:c25:a005:f0ea/1272c19:dd:d9:dd:c25:c25:a005:f0eb
1192c19:dd:d9:dd:c25:c25:a005:f0ec/1272c19:dd:d9:dd:c25:c25:a005:f0ed
1202c19:dd:d9:dd:c25:c25:a005:f0ee/1272c19:dd:d9:dd:c25:c25:a005:f0ef
1212c19:dd:d9:dd:c25:c25:a005:f0f0/1272c19:dd:d9:dd:c25:c25:a005:f0f1
1222c19:dd:d9:dd:c25:c25:a005:f0f2/1272c19:dd:d9:dd:c25:c25:a005:f0f3
1232c19:dd:d9:dd:c25:c25:a005:f0f4/1272c19:dd:d9:dd:c25:c25:a005:f0f5
1242c19:dd:d9:dd:c25:c25:a005:f0f6/1272c19:dd:d9:dd:c25:c25:a005:f0f7
1252c19:dd:d9:dd:c25:c25:a005:f0f8/1272c19:dd:d9:dd:c25:c25:a005:f0f9
1262c19:dd:d9:dd:c25:c25:a005:f0fa/1272c19:dd:d9:dd:c25:c25:a005:f0fb
1272c19:dd:d9:dd:c25:c25:a005:f0fc/1272c19:dd:d9:dd:c25:c25:a005:f0fd
1282c19:dd:d9:dd:c25:c25:a005:f0fe/1272c19:dd:d9:dd:c25:c25:a005:f0ff
1292c19:dd:d9:dd:c25:c25:a005:f100/1272c19:dd:d9:dd:c25:c25:a005:f101
1302c19:dd:d9:dd:c25:c25:a005:f102/1272c19:dd:d9:dd:c25:c25:a005:f103
1312c19:dd:d9:dd:c25:c25:a005:f104/1272c19:dd:d9:dd:c25:c25:a005:f105
1322c19:dd:d9:dd:c25:c25:a005:f106/1272c19:dd:d9:dd:c25:c25:a005:f107
1332c19:dd:d9:dd:c25:c25:a005:f108/1272c19:dd:d9:dd:c25:c25:a005:f109
1342c19:dd:d9:dd:c25:c25:a005:f10a/1272c19:dd:d9:dd:c25:c25:a005:f10b
1352c19:dd:d9:dd:c25:c25:a005:f10c/1272c19:dd:d9:dd:c25:c25:a005:f10d
1362c19:dd:d9:dd:c25:c25:a005:f10e/1272c19:dd:d9:dd:c25:c25:a005:f10f
1372c19:dd:d9:dd:c25:c25:a005:f110/1272c19:dd:d9:dd:c25:c25:a005:f111
1382c19:dd:d9:dd:c25:c25:a005:f112/1272c19:dd:d9:dd:c25:c25:a005:f113
1392c19:dd:d9:dd:c25:c25:a005:f114/1272c19:dd:d9:dd:c25:c25:a005:f115
1402c19:dd:d9:dd:c25:c25:a005:f116/1272c19:dd:d9:dd:c25:c25:a005:f117
1412c19:dd:d9:dd:c25:c25:a005:f118/1272c19:dd:d9:dd:c25:c25:a005:f119
1422c19:dd:d9:dd:c25:c25:a005:f11a/1272c19:dd:d9:dd:c25:c25:a005:f11b
1432c19:dd:d9:dd:c25:c25:a005:f11c/1272c19:dd:d9:dd:c25:c25:a005:f11d
1442c19:dd:d9:dd:c25:c25:a005:f11e/1272c19:dd:d9:dd:c25:c25:a005:f11f
1452c19:dd:d9:dd:c25:c25:a005:f120/1272c19:dd:d9:dd:c25:c25:a005:f121
1462c19:dd:d9:dd:c25:c25:a005:f122/1272c19:dd:d9:dd:c25:c25:a005:f123
1472c19:dd:d9:dd:c25:c25:a005:f124/1272c19:dd:d9:dd:c25:c25:a005:f125
1482c19:dd:d9:dd:c25:c25:a005:f126/1272c19:dd:d9:dd:c25:c25:a005:f127
1492c19:dd:d9:dd:c25:c25:a005:f128/1272c19:dd:d9:dd:c25:c25:a005:f129
1502c19:dd:d9:dd:c25:c25:a005:f12a/1272c19:dd:d9:dd:c25:c25:a005:f12b
1512c19:dd:d9:dd:c25:c25:a005:f12c/1272c19:dd:d9:dd:c25:c25:a005:f12d
1522c19:dd:d9:dd:c25:c25:a005:f12e/1272c19:dd:d9:dd:c25:c25:a005:f12f
1532c19:dd:d9:dd:c25:c25:a005:f130/1272c19:dd:d9:dd:c25:c25:a005:f131
1542c19:dd:d9:dd:c25:c25:a005:f132/1272c19:dd:d9:dd:c25:c25:a005:f133
1552c19:dd:d9:dd:c25:c25:a005:f134/1272c19:dd:d9:dd:c25:c25:a005:f135
1562c19:dd:d9:dd:c25:c25:a005:f136/1272c19:dd:d9:dd:c25:c25:a005:f137
1572c19:dd:d9:dd:c25:c25:a005:f138/1272c19:dd:d9:dd:c25:c25:a005:f139
1582c19:dd:d9:dd:c25:c25:a005:f13a/1272c19:dd:d9:dd:c25:c25:a005:f13b
1592c19:dd:d9:dd:c25:c25:a005:f13c/1272c19:dd:d9:dd:c25:c25:a005:f13d
1602c19:dd:d9:dd:c25:c25:a005:f13e/1272c19:dd:d9:dd:c25:c25:a005:f13f
1612c19:dd:d9:dd:c25:c25:a005:f140/1272c19:dd:d9:dd:c25:c25:a005:f141
1622c19:dd:d9:dd:c25:c25:a005:f142/1272c19:dd:d9:dd:c25:c25:a005:f143
1632c19:dd:d9:dd:c25:c25:a005:f144/1272c19:dd:d9:dd:c25:c25:a005:f145
1642c19:dd:d9:dd:c25:c25:a005:f146/1272c19:dd:d9:dd:c25:c25:a005:f147
1652c19:dd:d9:dd:c25:c25:a005:f148/1272c19:dd:d9:dd:c25:c25:a005:f149
1662c19:dd:d9:dd:c25:c25:a005:f14a/1272c19:dd:d9:dd:c25:c25:a005:f14b
1672c19:dd:d9:dd:c25:c25:a005:f14c/1272c19:dd:d9:dd:c25:c25:a005:f14d
1682c19:dd:d9:dd:c25:c25:a005:f14e/1272c19:dd:d9:dd:c25:c25:a005:f14f
1692c19:dd:d9:dd:c25:c25:a005:f150/1272c19:dd:d9:dd:c25:c25:a005:f151
1702c19:dd:d9:dd:c25:c25:a005:f152/1272c19:dd:d9:dd:c25:c25:a005:f153
1712c19:dd:d9:dd:c25:c25:a005:f154/1272c19:dd:d9:dd:c25:c25:a005:f155
1722c19:dd:d9:dd:c25:c25:a005:f156/1272c19:dd:d9:dd:c25:c25:a005:f157
1732c19:dd:d9:dd:c25:c25:a005:f158/1272c19:dd:d9:dd:c25:c25:a005:f159
1742c19:dd:d9:dd:c25:c25:a005:f15a/1272c19:dd:d9:dd:c25:c25:a005:f15b
1752c19:dd:d9:dd:c25:c25:a005:f15c/1272c19:dd:d9:dd:c25:c25:a005:f15d
1762c19:dd:d9:dd:c25:c25:a005:f15e/1272c19:dd:d9:dd:c25:c25:a005:f15f
1772c19:dd:d9:dd:c25:c25:a005:f160/1272c19:dd:d9:dd:c25:c25:a005:f161
1782c19:dd:d9:dd:c25:c25:a005:f162/1272c19:dd:d9:dd:c25:c25:a005:f163
1792c19:dd:d9:dd:c25:c25:a005:f164/1272c19:dd:d9:dd:c25:c25:a005:f165
1802c19:dd:d9:dd:c25:c25:a005:f166/1272c19:dd:d9:dd:c25:c25:a005:f167
1812c19:dd:d9:dd:c25:c25:a005:f168/1272c19:dd:d9:dd:c25:c25:a005:f169
1822c19:dd:d9:dd:c25:c25:a005:f16a/1272c19:dd:d9:dd:c25:c25:a005:f16b
1832c19:dd:d9:dd:c25:c25:a005:f16c/1272c19:dd:d9:dd:c25:c25:a005:f16d
1842c19:dd:d9:dd:c25:c25:a005:f16e/1272c19:dd:d9:dd:c25:c25:a005:f16f
1852c19:dd:d9:dd:c25:c25:a005:f170/1272c19:dd:d9:dd:c25:c25:a005:f171
1862c19:dd:d9:dd:c25:c25:a005:f172/1272c19:dd:d9:dd:c25:c25:a005:f173
1872c19:dd:d9:dd:c25:c25:a005:f174/1272c19:dd:d9:dd:c25:c25:a005:f175
1882c19:dd:d9:dd:c25:c25:a005:f176/1272c19:dd:d9:dd:c25:c25:a005:f177
1892c19:dd:d9:dd:c25:c25:a005:f178/1272c19:dd:d9:dd:c25:c25:a005:f179
1902c19:dd:d9:dd:c25:c25:a005:f17a/1272c19:dd:d9:dd:c25:c25:a005:f17b
1912c19:dd:d9:dd:c25:c25:a005:f17c/1272c19:dd:d9:dd:c25:c25:a005:f17d
1922c19:dd:d9:dd:c25:c25:a005:f17e/1272c19:dd:d9:dd:c25:c25:a005:f17f
1932c19:dd:d9:dd:c25:c25:a005:f180/1272c19:dd:d9:dd:c25:c25:a005:f181
1942c19:dd:d9:dd:c25:c25:a005:f182/1272c19:dd:d9:dd:c25:c25:a005:f183
1952c19:dd:d9:dd:c25:c25:a005:f184/1272c19:dd:d9:dd:c25:c25:a005:f185
1962c19:dd:d9:dd:c25:c25:a005:f186/1272c19:dd:d9:dd:c25:c25:a005:f187
1972c19:dd:d9:dd:c25:c25:a005:f188/1272c19:dd:d9:dd:c25:c25:a005:f189
1982c19:dd:d9:dd:c25:c25:a005:f18a/1272c19:dd:d9:dd:c25:c25:a005:f18b
1992c19:dd:d9:dd:c25:c25:a005:f18c/1272c19:dd:d9:dd:c25:c25:a005:f18d
2002c19:dd:d9:dd:c25:c25:a005:f18e/1272c19:dd:d9:dd:c25:c25:a005:f18f
2012c19:dd:d9:dd:c25:c25:a005:f190/1272c19:dd:d9:dd:c25:c25:a005:f191
2022c19:dd:d9:dd:c25:c25:a005:f192/1272c19:dd:d9:dd:c25:c25:a005:f193
2032c19:dd:d9:dd:c25:c25:a005:f194/1272c19:dd:d9:dd:c25:c25:a005:f195
2042c19:dd:d9:dd:c25:c25:a005:f196/1272c19:dd:d9:dd:c25:c25:a005:f197
2052c19:dd:d9:dd:c25:c25:a005:f198/1272c19:dd:d9:dd:c25:c25:a005:f199
2062c19:dd:d9:dd:c25:c25:a005:f19a/1272c19:dd:d9:dd:c25:c25:a005:f19b
2072c19:dd:d9:dd:c25:c25:a005:f19c/1272c19:dd:d9:dd:c25:c25:a005:f19d
2082c19:dd:d9:dd:c25:c25:a005:f19e/1272c19:dd:d9:dd:c25:c25:a005:f19f
2092c19:dd:d9:dd:c25:c25:a005:f1a0/1272c19:dd:d9:dd:c25:c25:a005:f1a1
2102c19:dd:d9:dd:c25:c25:a005:f1a2/1272c19:dd:d9:dd:c25:c25:a005:f1a3
2112c19:dd:d9:dd:c25:c25:a005:f1a4/1272c19:dd:d9:dd:c25:c25:a005:f1a5
2122c19:dd:d9:dd:c25:c25:a005:f1a6/1272c19:dd:d9:dd:c25:c25:a005:f1a7
2132c19:dd:d9:dd:c25:c25:a005:f1a8/1272c19:dd:d9:dd:c25:c25:a005:f1a9
2142c19:dd:d9:dd:c25:c25:a005:f1aa/1272c19:dd:d9:dd:c25:c25:a005:f1ab
2152c19:dd:d9:dd:c25:c25:a005:f1ac/1272c19:dd:d9:dd:c25:c25:a005:f1ad
2162c19:dd:d9:dd:c25:c25:a005:f1ae/1272c19:dd:d9:dd:c25:c25:a005:f1af
2172c19:dd:d9:dd:c25:c25:a005:f1b0/1272c19:dd:d9:dd:c25:c25:a005:f1b1
2182c19:dd:d9:dd:c25:c25:a005:f1b2/1272c19:dd:d9:dd:c25:c25:a005:f1b3
2192c19:dd:d9:dd:c25:c25:a005:f1b4/1272c19:dd:d9:dd:c25:c25:a005:f1b5
2202c19:dd:d9:dd:c25:c25:a005:f1b6/1272c19:dd:d9:dd:c25:c25:a005:f1b7
2212c19:dd:d9:dd:c25:c25:a005:f1b8/1272c19:dd:d9:dd:c25:c25:a005:f1b9
2222c19:dd:d9:dd:c25:c25:a005:f1ba/1272c19:dd:d9:dd:c25:c25:a005:f1bb
2232c19:dd:d9:dd:c25:c25:a005:f1bc/1272c19:dd:d9:dd:c25:c25:a005:f1bd
2242c19:dd:d9:dd:c25:c25:a005:f1be/1272c19:dd:d9:dd:c25:c25:a005:f1bf
2252c19:dd:d9:dd:c25:c25:a005:f1c0/1272c19:dd:d9:dd:c25:c25:a005:f1c1
2262c19:dd:d9:dd:c25:c25:a005:f1c2/1272c19:dd:d9:dd:c25:c25:a005:f1c3
2272c19:dd:d9:dd:c25:c25:a005:f1c4/1272c19:dd:d9:dd:c25:c25:a005:f1c5
2282c19:dd:d9:dd:c25:c25:a005:f1c6/1272c19:dd:d9:dd:c25:c25:a005:f1c7
2292c19:dd:d9:dd:c25:c25:a005:f1c8/1272c19:dd:d9:dd:c25:c25:a005:f1c9
2302c19:dd:d9:dd:c25:c25:a005:f1ca/1272c19:dd:d9:dd:c25:c25:a005:f1cb
2312c19:dd:d9:dd:c25:c25:a005:f1cc/1272c19:dd:d9:dd:c25:c25:a005:f1cd
2322c19:dd:d9:dd:c25:c25:a005:f1ce/1272c19:dd:d9:dd:c25:c25:a005:f1cf
2332c19:dd:d9:dd:c25:c25:a005:f1d0/1272c19:dd:d9:dd:c25:c25:a005:f1d1
2342c19:dd:d9:dd:c25:c25:a005:f1d2/1272c19:dd:d9:dd:c25:c25:a005:f1d3
2352c19:dd:d9:dd:c25:c25:a005:f1d4/1272c19:dd:d9:dd:c25:c25:a005:f1d5
2362c19:dd:d9:dd:c25:c25:a005:f1d6/1272c19:dd:d9:dd:c25:c25:a005:f1d7
2372c19:dd:d9:dd:c25:c25:a005:f1d8/1272c19:dd:d9:dd:c25:c25:a005:f1d9
2382c19:dd:d9:dd:c25:c25:a005:f1da/1272c19:dd:d9:dd:c25:c25:a005:f1db
2392c19:dd:d9:dd:c25:c25:a005:f1dc/1272c19:dd:d9:dd:c25:c25:a005:f1dd
2402c19:dd:d9:dd:c25:c25:a005:f1de/1272c19:dd:d9:dd:c25:c25:a005:f1df
2412c19:dd:d9:dd:c25:c25:a005:f1e0/1272c19:dd:d9:dd:c25:c25:a005:f1e1
2422c19:dd:d9:dd:c25:c25:a005:f1e2/1272c19:dd:d9:dd:c25:c25:a005:f1e3
2432c19:dd:d9:dd:c25:c25:a005:f1e4/1272c19:dd:d9:dd:c25:c25:a005:f1e5
2442c19:dd:d9:dd:c25:c25:a005:f1e6/1272c19:dd:d9:dd:c25:c25:a005:f1e7
2452c19:dd:d9:dd:c25:c25:a005:f1e8/1272c19:dd:d9:dd:c25:c25:a005:f1e9
2462c19:dd:d9:dd:c25:c25:a005:f1ea/1272c19:dd:d9:dd:c25:c25:a005:f1eb
2472c19:dd:d9:dd:c25:c25:a005:f1ec/1272c19:dd:d9:dd:c25:c25:a005:f1ed
2482c19:dd:d9:dd:c25:c25:a005:f1ee/1272c19:dd:d9:dd:c25:c25:a005:f1ef
2492c19:dd:d9:dd:c25:c25:a005:f1f0/1272c19:dd:d9:dd:c25:c25:a005:f1f1
2502c19:dd:d9:dd:c25:c25:a005:f1f2/1272c19:dd:d9:dd:c25:c25:a005:f1f3
2512c19:dd:d9:dd:c25:c25:a005:f1f4/1272c19:dd:d9:dd:c25:c25:a005:f1f5
2522c19:dd:d9:dd:c25:c25:a005:f1f6/1272c19:dd:d9:dd:c25:c25:a005:f1f7
2532c19:dd:d9:dd:c25:c25:a005:f1f8/1272c19:dd:d9:dd:c25:c25:a005:f1f9
2542c19:dd:d9:dd:c25:c25:a005:f1fa/1272c19:dd:d9:dd:c25:c25:a005:f1fb
2552c19:dd:d9:dd:c25:c25:a005:f1fc/1272c19:dd:d9:dd:c25:c25:a005:f1fd
2562c19:dd:d9:dd:c25:c25:a005:f1fe/1272c19:dd:d9:dd:c25:c25:a005:f1ff

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.