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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:e004:f000/116
First address
2c19:dd:d9:dd:c25:c25:e004:f000
Last address
2c19:dd:d9:dd:c25:c25:e004:ffff
Addresses
4,096
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:e004:f000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
f.4.0.0.e.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/128
/117 (2)/118 (4)/119 (8)/120 (16)/124 (256)/127 (2,048)/128 (4,096)

2c19:dd:d9:dd:c25:c25:e004:f000/116 makes 4,096 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:e004:f000/1282c19:dd:d9:dd:c25:c25:e004:f000
22c19:dd:d9:dd:c25:c25:e004:f001/1282c19:dd:d9:dd:c25:c25:e004:f001
32c19:dd:d9:dd:c25:c25:e004:f002/1282c19:dd:d9:dd:c25:c25:e004:f002
42c19:dd:d9:dd:c25:c25:e004:f003/1282c19:dd:d9:dd:c25:c25:e004:f003
52c19:dd:d9:dd:c25:c25:e004:f004/1282c19:dd:d9:dd:c25:c25:e004:f004
62c19:dd:d9:dd:c25:c25:e004:f005/1282c19:dd:d9:dd:c25:c25:e004:f005
72c19:dd:d9:dd:c25:c25:e004:f006/1282c19:dd:d9:dd:c25:c25:e004:f006
82c19:dd:d9:dd:c25:c25:e004:f007/1282c19:dd:d9:dd:c25:c25:e004:f007
92c19:dd:d9:dd:c25:c25:e004:f008/1282c19:dd:d9:dd:c25:c25:e004:f008
102c19:dd:d9:dd:c25:c25:e004:f009/1282c19:dd:d9:dd:c25:c25:e004:f009
112c19:dd:d9:dd:c25:c25:e004:f00a/1282c19:dd:d9:dd:c25:c25:e004:f00a
122c19:dd:d9:dd:c25:c25:e004:f00b/1282c19:dd:d9:dd:c25:c25:e004:f00b
132c19:dd:d9:dd:c25:c25:e004:f00c/1282c19:dd:d9:dd:c25:c25:e004:f00c
142c19:dd:d9:dd:c25:c25:e004:f00d/1282c19:dd:d9:dd:c25:c25:e004:f00d
152c19:dd:d9:dd:c25:c25:e004:f00e/1282c19:dd:d9:dd:c25:c25:e004:f00e
162c19:dd:d9:dd:c25:c25:e004:f00f/1282c19:dd:d9:dd:c25:c25:e004:f00f
172c19:dd:d9:dd:c25:c25:e004:f010/1282c19:dd:d9:dd:c25:c25:e004:f010
182c19:dd:d9:dd:c25:c25:e004:f011/1282c19:dd:d9:dd:c25:c25:e004:f011
192c19:dd:d9:dd:c25:c25:e004:f012/1282c19:dd:d9:dd:c25:c25:e004:f012
202c19:dd:d9:dd:c25:c25:e004:f013/1282c19:dd:d9:dd:c25:c25:e004:f013
212c19:dd:d9:dd:c25:c25:e004:f014/1282c19:dd:d9:dd:c25:c25:e004:f014
222c19:dd:d9:dd:c25:c25:e004:f015/1282c19:dd:d9:dd:c25:c25:e004:f015
232c19:dd:d9:dd:c25:c25:e004:f016/1282c19:dd:d9:dd:c25:c25:e004:f016
242c19:dd:d9:dd:c25:c25:e004:f017/1282c19:dd:d9:dd:c25:c25:e004:f017
252c19:dd:d9:dd:c25:c25:e004:f018/1282c19:dd:d9:dd:c25:c25:e004:f018
262c19:dd:d9:dd:c25:c25:e004:f019/1282c19:dd:d9:dd:c25:c25:e004:f019
272c19:dd:d9:dd:c25:c25:e004:f01a/1282c19:dd:d9:dd:c25:c25:e004:f01a
282c19:dd:d9:dd:c25:c25:e004:f01b/1282c19:dd:d9:dd:c25:c25:e004:f01b
292c19:dd:d9:dd:c25:c25:e004:f01c/1282c19:dd:d9:dd:c25:c25:e004:f01c
302c19:dd:d9:dd:c25:c25:e004:f01d/1282c19:dd:d9:dd:c25:c25:e004:f01d
312c19:dd:d9:dd:c25:c25:e004:f01e/1282c19:dd:d9:dd:c25:c25:e004:f01e
322c19:dd:d9:dd:c25:c25:e004:f01f/1282c19:dd:d9:dd:c25:c25:e004:f01f
332c19:dd:d9:dd:c25:c25:e004:f020/1282c19:dd:d9:dd:c25:c25:e004:f020
342c19:dd:d9:dd:c25:c25:e004:f021/1282c19:dd:d9:dd:c25:c25:e004:f021
352c19:dd:d9:dd:c25:c25:e004:f022/1282c19:dd:d9:dd:c25:c25:e004:f022
362c19:dd:d9:dd:c25:c25:e004:f023/1282c19:dd:d9:dd:c25:c25:e004:f023
372c19:dd:d9:dd:c25:c25:e004:f024/1282c19:dd:d9:dd:c25:c25:e004:f024
382c19:dd:d9:dd:c25:c25:e004:f025/1282c19:dd:d9:dd:c25:c25:e004:f025
392c19:dd:d9:dd:c25:c25:e004:f026/1282c19:dd:d9:dd:c25:c25:e004:f026
402c19:dd:d9:dd:c25:c25:e004:f027/1282c19:dd:d9:dd:c25:c25:e004:f027
412c19:dd:d9:dd:c25:c25:e004:f028/1282c19:dd:d9:dd:c25:c25:e004:f028
422c19:dd:d9:dd:c25:c25:e004:f029/1282c19:dd:d9:dd:c25:c25:e004:f029
432c19:dd:d9:dd:c25:c25:e004:f02a/1282c19:dd:d9:dd:c25:c25:e004:f02a
442c19:dd:d9:dd:c25:c25:e004:f02b/1282c19:dd:d9:dd:c25:c25:e004:f02b
452c19:dd:d9:dd:c25:c25:e004:f02c/1282c19:dd:d9:dd:c25:c25:e004:f02c
462c19:dd:d9:dd:c25:c25:e004:f02d/1282c19:dd:d9:dd:c25:c25:e004:f02d
472c19:dd:d9:dd:c25:c25:e004:f02e/1282c19:dd:d9:dd:c25:c25:e004:f02e
482c19:dd:d9:dd:c25:c25:e004:f02f/1282c19:dd:d9:dd:c25:c25:e004:f02f
492c19:dd:d9:dd:c25:c25:e004:f030/1282c19:dd:d9:dd:c25:c25:e004:f030
502c19:dd:d9:dd:c25:c25:e004:f031/1282c19:dd:d9:dd:c25:c25:e004:f031
512c19:dd:d9:dd:c25:c25:e004:f032/1282c19:dd:d9:dd:c25:c25:e004:f032
522c19:dd:d9:dd:c25:c25:e004:f033/1282c19:dd:d9:dd:c25:c25:e004:f033
532c19:dd:d9:dd:c25:c25:e004:f034/1282c19:dd:d9:dd:c25:c25:e004:f034
542c19:dd:d9:dd:c25:c25:e004:f035/1282c19:dd:d9:dd:c25:c25:e004:f035
552c19:dd:d9:dd:c25:c25:e004:f036/1282c19:dd:d9:dd:c25:c25:e004:f036
562c19:dd:d9:dd:c25:c25:e004:f037/1282c19:dd:d9:dd:c25:c25:e004:f037
572c19:dd:d9:dd:c25:c25:e004:f038/1282c19:dd:d9:dd:c25:c25:e004:f038
582c19:dd:d9:dd:c25:c25:e004:f039/1282c19:dd:d9:dd:c25:c25:e004:f039
592c19:dd:d9:dd:c25:c25:e004:f03a/1282c19:dd:d9:dd:c25:c25:e004:f03a
602c19:dd:d9:dd:c25:c25:e004:f03b/1282c19:dd:d9:dd:c25:c25:e004:f03b
612c19:dd:d9:dd:c25:c25:e004:f03c/1282c19:dd:d9:dd:c25:c25:e004:f03c
622c19:dd:d9:dd:c25:c25:e004:f03d/1282c19:dd:d9:dd:c25:c25:e004:f03d
632c19:dd:d9:dd:c25:c25:e004:f03e/1282c19:dd:d9:dd:c25:c25:e004:f03e
642c19:dd:d9:dd:c25:c25:e004:f03f/1282c19:dd:d9:dd:c25:c25:e004:f03f
652c19:dd:d9:dd:c25:c25:e004:f040/1282c19:dd:d9:dd:c25:c25:e004:f040
662c19:dd:d9:dd:c25:c25:e004:f041/1282c19:dd:d9:dd:c25:c25:e004:f041
672c19:dd:d9:dd:c25:c25:e004:f042/1282c19:dd:d9:dd:c25:c25:e004:f042
682c19:dd:d9:dd:c25:c25:e004:f043/1282c19:dd:d9:dd:c25:c25:e004:f043
692c19:dd:d9:dd:c25:c25:e004:f044/1282c19:dd:d9:dd:c25:c25:e004:f044
702c19:dd:d9:dd:c25:c25:e004:f045/1282c19:dd:d9:dd:c25:c25:e004:f045
712c19:dd:d9:dd:c25:c25:e004:f046/1282c19:dd:d9:dd:c25:c25:e004:f046
722c19:dd:d9:dd:c25:c25:e004:f047/1282c19:dd:d9:dd:c25:c25:e004:f047
732c19:dd:d9:dd:c25:c25:e004:f048/1282c19:dd:d9:dd:c25:c25:e004:f048
742c19:dd:d9:dd:c25:c25:e004:f049/1282c19:dd:d9:dd:c25:c25:e004:f049
752c19:dd:d9:dd:c25:c25:e004:f04a/1282c19:dd:d9:dd:c25:c25:e004:f04a
762c19:dd:d9:dd:c25:c25:e004:f04b/1282c19:dd:d9:dd:c25:c25:e004:f04b
772c19:dd:d9:dd:c25:c25:e004:f04c/1282c19:dd:d9:dd:c25:c25:e004:f04c
782c19:dd:d9:dd:c25:c25:e004:f04d/1282c19:dd:d9:dd:c25:c25:e004:f04d
792c19:dd:d9:dd:c25:c25:e004:f04e/1282c19:dd:d9:dd:c25:c25:e004:f04e
802c19:dd:d9:dd:c25:c25:e004:f04f/1282c19:dd:d9:dd:c25:c25:e004:f04f
812c19:dd:d9:dd:c25:c25:e004:f050/1282c19:dd:d9:dd:c25:c25:e004:f050
822c19:dd:d9:dd:c25:c25:e004:f051/1282c19:dd:d9:dd:c25:c25:e004:f051
832c19:dd:d9:dd:c25:c25:e004:f052/1282c19:dd:d9:dd:c25:c25:e004:f052
842c19:dd:d9:dd:c25:c25:e004:f053/1282c19:dd:d9:dd:c25:c25:e004:f053
852c19:dd:d9:dd:c25:c25:e004:f054/1282c19:dd:d9:dd:c25:c25:e004:f054
862c19:dd:d9:dd:c25:c25:e004:f055/1282c19:dd:d9:dd:c25:c25:e004:f055
872c19:dd:d9:dd:c25:c25:e004:f056/1282c19:dd:d9:dd:c25:c25:e004:f056
882c19:dd:d9:dd:c25:c25:e004:f057/1282c19:dd:d9:dd:c25:c25:e004:f057
892c19:dd:d9:dd:c25:c25:e004:f058/1282c19:dd:d9:dd:c25:c25:e004:f058
902c19:dd:d9:dd:c25:c25:e004:f059/1282c19:dd:d9:dd:c25:c25:e004:f059
912c19:dd:d9:dd:c25:c25:e004:f05a/1282c19:dd:d9:dd:c25:c25:e004:f05a
922c19:dd:d9:dd:c25:c25:e004:f05b/1282c19:dd:d9:dd:c25:c25:e004:f05b
932c19:dd:d9:dd:c25:c25:e004:f05c/1282c19:dd:d9:dd:c25:c25:e004:f05c
942c19:dd:d9:dd:c25:c25:e004:f05d/1282c19:dd:d9:dd:c25:c25:e004:f05d
952c19:dd:d9:dd:c25:c25:e004:f05e/1282c19:dd:d9:dd:c25:c25:e004:f05e
962c19:dd:d9:dd:c25:c25:e004:f05f/1282c19:dd:d9:dd:c25:c25:e004:f05f
972c19:dd:d9:dd:c25:c25:e004:f060/1282c19:dd:d9:dd:c25:c25:e004:f060
982c19:dd:d9:dd:c25:c25:e004:f061/1282c19:dd:d9:dd:c25:c25:e004:f061
992c19:dd:d9:dd:c25:c25:e004:f062/1282c19:dd:d9:dd:c25:c25:e004:f062
1002c19:dd:d9:dd:c25:c25:e004:f063/1282c19:dd:d9:dd:c25:c25:e004:f063
1012c19:dd:d9:dd:c25:c25:e004:f064/1282c19:dd:d9:dd:c25:c25:e004:f064
1022c19:dd:d9:dd:c25:c25:e004:f065/1282c19:dd:d9:dd:c25:c25:e004:f065
1032c19:dd:d9:dd:c25:c25:e004:f066/1282c19:dd:d9:dd:c25:c25:e004:f066
1042c19:dd:d9:dd:c25:c25:e004:f067/1282c19:dd:d9:dd:c25:c25:e004:f067
1052c19:dd:d9:dd:c25:c25:e004:f068/1282c19:dd:d9:dd:c25:c25:e004:f068
1062c19:dd:d9:dd:c25:c25:e004:f069/1282c19:dd:d9:dd:c25:c25:e004:f069
1072c19:dd:d9:dd:c25:c25:e004:f06a/1282c19:dd:d9:dd:c25:c25:e004:f06a
1082c19:dd:d9:dd:c25:c25:e004:f06b/1282c19:dd:d9:dd:c25:c25:e004:f06b
1092c19:dd:d9:dd:c25:c25:e004:f06c/1282c19:dd:d9:dd:c25:c25:e004:f06c
1102c19:dd:d9:dd:c25:c25:e004:f06d/1282c19:dd:d9:dd:c25:c25:e004:f06d
1112c19:dd:d9:dd:c25:c25:e004:f06e/1282c19:dd:d9:dd:c25:c25:e004:f06e
1122c19:dd:d9:dd:c25:c25:e004:f06f/1282c19:dd:d9:dd:c25:c25:e004:f06f
1132c19:dd:d9:dd:c25:c25:e004:f070/1282c19:dd:d9:dd:c25:c25:e004:f070
1142c19:dd:d9:dd:c25:c25:e004:f071/1282c19:dd:d9:dd:c25:c25:e004:f071
1152c19:dd:d9:dd:c25:c25:e004:f072/1282c19:dd:d9:dd:c25:c25:e004:f072
1162c19:dd:d9:dd:c25:c25:e004:f073/1282c19:dd:d9:dd:c25:c25:e004:f073
1172c19:dd:d9:dd:c25:c25:e004:f074/1282c19:dd:d9:dd:c25:c25:e004:f074
1182c19:dd:d9:dd:c25:c25:e004:f075/1282c19:dd:d9:dd:c25:c25:e004:f075
1192c19:dd:d9:dd:c25:c25:e004:f076/1282c19:dd:d9:dd:c25:c25:e004:f076
1202c19:dd:d9:dd:c25:c25:e004:f077/1282c19:dd:d9:dd:c25:c25:e004:f077
1212c19:dd:d9:dd:c25:c25:e004:f078/1282c19:dd:d9:dd:c25:c25:e004:f078
1222c19:dd:d9:dd:c25:c25:e004:f079/1282c19:dd:d9:dd:c25:c25:e004:f079
1232c19:dd:d9:dd:c25:c25:e004:f07a/1282c19:dd:d9:dd:c25:c25:e004:f07a
1242c19:dd:d9:dd:c25:c25:e004:f07b/1282c19:dd:d9:dd:c25:c25:e004:f07b
1252c19:dd:d9:dd:c25:c25:e004:f07c/1282c19:dd:d9:dd:c25:c25:e004:f07c
1262c19:dd:d9:dd:c25:c25:e004:f07d/1282c19:dd:d9:dd:c25:c25:e004:f07d
1272c19:dd:d9:dd:c25:c25:e004:f07e/1282c19:dd:d9:dd:c25:c25:e004:f07e
1282c19:dd:d9:dd:c25:c25:e004:f07f/1282c19:dd:d9:dd:c25:c25:e004:f07f
1292c19:dd:d9:dd:c25:c25:e004:f080/1282c19:dd:d9:dd:c25:c25:e004:f080
1302c19:dd:d9:dd:c25:c25:e004:f081/1282c19:dd:d9:dd:c25:c25:e004:f081
1312c19:dd:d9:dd:c25:c25:e004:f082/1282c19:dd:d9:dd:c25:c25:e004:f082
1322c19:dd:d9:dd:c25:c25:e004:f083/1282c19:dd:d9:dd:c25:c25:e004:f083
1332c19:dd:d9:dd:c25:c25:e004:f084/1282c19:dd:d9:dd:c25:c25:e004:f084
1342c19:dd:d9:dd:c25:c25:e004:f085/1282c19:dd:d9:dd:c25:c25:e004:f085
1352c19:dd:d9:dd:c25:c25:e004:f086/1282c19:dd:d9:dd:c25:c25:e004:f086
1362c19:dd:d9:dd:c25:c25:e004:f087/1282c19:dd:d9:dd:c25:c25:e004:f087
1372c19:dd:d9:dd:c25:c25:e004:f088/1282c19:dd:d9:dd:c25:c25:e004:f088
1382c19:dd:d9:dd:c25:c25:e004:f089/1282c19:dd:d9:dd:c25:c25:e004:f089
1392c19:dd:d9:dd:c25:c25:e004:f08a/1282c19:dd:d9:dd:c25:c25:e004:f08a
1402c19:dd:d9:dd:c25:c25:e004:f08b/1282c19:dd:d9:dd:c25:c25:e004:f08b
1412c19:dd:d9:dd:c25:c25:e004:f08c/1282c19:dd:d9:dd:c25:c25:e004:f08c
1422c19:dd:d9:dd:c25:c25:e004:f08d/1282c19:dd:d9:dd:c25:c25:e004:f08d
1432c19:dd:d9:dd:c25:c25:e004:f08e/1282c19:dd:d9:dd:c25:c25:e004:f08e
1442c19:dd:d9:dd:c25:c25:e004:f08f/1282c19:dd:d9:dd:c25:c25:e004:f08f
1452c19:dd:d9:dd:c25:c25:e004:f090/1282c19:dd:d9:dd:c25:c25:e004:f090
1462c19:dd:d9:dd:c25:c25:e004:f091/1282c19:dd:d9:dd:c25:c25:e004:f091
1472c19:dd:d9:dd:c25:c25:e004:f092/1282c19:dd:d9:dd:c25:c25:e004:f092
1482c19:dd:d9:dd:c25:c25:e004:f093/1282c19:dd:d9:dd:c25:c25:e004:f093
1492c19:dd:d9:dd:c25:c25:e004:f094/1282c19:dd:d9:dd:c25:c25:e004:f094
1502c19:dd:d9:dd:c25:c25:e004:f095/1282c19:dd:d9:dd:c25:c25:e004:f095
1512c19:dd:d9:dd:c25:c25:e004:f096/1282c19:dd:d9:dd:c25:c25:e004:f096
1522c19:dd:d9:dd:c25:c25:e004:f097/1282c19:dd:d9:dd:c25:c25:e004:f097
1532c19:dd:d9:dd:c25:c25:e004:f098/1282c19:dd:d9:dd:c25:c25:e004:f098
1542c19:dd:d9:dd:c25:c25:e004:f099/1282c19:dd:d9:dd:c25:c25:e004:f099
1552c19:dd:d9:dd:c25:c25:e004:f09a/1282c19:dd:d9:dd:c25:c25:e004:f09a
1562c19:dd:d9:dd:c25:c25:e004:f09b/1282c19:dd:d9:dd:c25:c25:e004:f09b
1572c19:dd:d9:dd:c25:c25:e004:f09c/1282c19:dd:d9:dd:c25:c25:e004:f09c
1582c19:dd:d9:dd:c25:c25:e004:f09d/1282c19:dd:d9:dd:c25:c25:e004:f09d
1592c19:dd:d9:dd:c25:c25:e004:f09e/1282c19:dd:d9:dd:c25:c25:e004:f09e
1602c19:dd:d9:dd:c25:c25:e004:f09f/1282c19:dd:d9:dd:c25:c25:e004:f09f
1612c19:dd:d9:dd:c25:c25:e004:f0a0/1282c19:dd:d9:dd:c25:c25:e004:f0a0
1622c19:dd:d9:dd:c25:c25:e004:f0a1/1282c19:dd:d9:dd:c25:c25:e004:f0a1
1632c19:dd:d9:dd:c25:c25:e004:f0a2/1282c19:dd:d9:dd:c25:c25:e004:f0a2
1642c19:dd:d9:dd:c25:c25:e004:f0a3/1282c19:dd:d9:dd:c25:c25:e004:f0a3
1652c19:dd:d9:dd:c25:c25:e004:f0a4/1282c19:dd:d9:dd:c25:c25:e004:f0a4
1662c19:dd:d9:dd:c25:c25:e004:f0a5/1282c19:dd:d9:dd:c25:c25:e004:f0a5
1672c19:dd:d9:dd:c25:c25:e004:f0a6/1282c19:dd:d9:dd:c25:c25:e004:f0a6
1682c19:dd:d9:dd:c25:c25:e004:f0a7/1282c19:dd:d9:dd:c25:c25:e004:f0a7
1692c19:dd:d9:dd:c25:c25:e004:f0a8/1282c19:dd:d9:dd:c25:c25:e004:f0a8
1702c19:dd:d9:dd:c25:c25:e004:f0a9/1282c19:dd:d9:dd:c25:c25:e004:f0a9
1712c19:dd:d9:dd:c25:c25:e004:f0aa/1282c19:dd:d9:dd:c25:c25:e004:f0aa
1722c19:dd:d9:dd:c25:c25:e004:f0ab/1282c19:dd:d9:dd:c25:c25:e004:f0ab
1732c19:dd:d9:dd:c25:c25:e004:f0ac/1282c19:dd:d9:dd:c25:c25:e004:f0ac
1742c19:dd:d9:dd:c25:c25:e004:f0ad/1282c19:dd:d9:dd:c25:c25:e004:f0ad
1752c19:dd:d9:dd:c25:c25:e004:f0ae/1282c19:dd:d9:dd:c25:c25:e004:f0ae
1762c19:dd:d9:dd:c25:c25:e004:f0af/1282c19:dd:d9:dd:c25:c25:e004:f0af
1772c19:dd:d9:dd:c25:c25:e004:f0b0/1282c19:dd:d9:dd:c25:c25:e004:f0b0
1782c19:dd:d9:dd:c25:c25:e004:f0b1/1282c19:dd:d9:dd:c25:c25:e004:f0b1
1792c19:dd:d9:dd:c25:c25:e004:f0b2/1282c19:dd:d9:dd:c25:c25:e004:f0b2
1802c19:dd:d9:dd:c25:c25:e004:f0b3/1282c19:dd:d9:dd:c25:c25:e004:f0b3
1812c19:dd:d9:dd:c25:c25:e004:f0b4/1282c19:dd:d9:dd:c25:c25:e004:f0b4
1822c19:dd:d9:dd:c25:c25:e004:f0b5/1282c19:dd:d9:dd:c25:c25:e004:f0b5
1832c19:dd:d9:dd:c25:c25:e004:f0b6/1282c19:dd:d9:dd:c25:c25:e004:f0b6
1842c19:dd:d9:dd:c25:c25:e004:f0b7/1282c19:dd:d9:dd:c25:c25:e004:f0b7
1852c19:dd:d9:dd:c25:c25:e004:f0b8/1282c19:dd:d9:dd:c25:c25:e004:f0b8
1862c19:dd:d9:dd:c25:c25:e004:f0b9/1282c19:dd:d9:dd:c25:c25:e004:f0b9
1872c19:dd:d9:dd:c25:c25:e004:f0ba/1282c19:dd:d9:dd:c25:c25:e004:f0ba
1882c19:dd:d9:dd:c25:c25:e004:f0bb/1282c19:dd:d9:dd:c25:c25:e004:f0bb
1892c19:dd:d9:dd:c25:c25:e004:f0bc/1282c19:dd:d9:dd:c25:c25:e004:f0bc
1902c19:dd:d9:dd:c25:c25:e004:f0bd/1282c19:dd:d9:dd:c25:c25:e004:f0bd
1912c19:dd:d9:dd:c25:c25:e004:f0be/1282c19:dd:d9:dd:c25:c25:e004:f0be
1922c19:dd:d9:dd:c25:c25:e004:f0bf/1282c19:dd:d9:dd:c25:c25:e004:f0bf
1932c19:dd:d9:dd:c25:c25:e004:f0c0/1282c19:dd:d9:dd:c25:c25:e004:f0c0
1942c19:dd:d9:dd:c25:c25:e004:f0c1/1282c19:dd:d9:dd:c25:c25:e004:f0c1
1952c19:dd:d9:dd:c25:c25:e004:f0c2/1282c19:dd:d9:dd:c25:c25:e004:f0c2
1962c19:dd:d9:dd:c25:c25:e004:f0c3/1282c19:dd:d9:dd:c25:c25:e004:f0c3
1972c19:dd:d9:dd:c25:c25:e004:f0c4/1282c19:dd:d9:dd:c25:c25:e004:f0c4
1982c19:dd:d9:dd:c25:c25:e004:f0c5/1282c19:dd:d9:dd:c25:c25:e004:f0c5
1992c19:dd:d9:dd:c25:c25:e004:f0c6/1282c19:dd:d9:dd:c25:c25:e004:f0c6
2002c19:dd:d9:dd:c25:c25:e004:f0c7/1282c19:dd:d9:dd:c25:c25:e004:f0c7
2012c19:dd:d9:dd:c25:c25:e004:f0c8/1282c19:dd:d9:dd:c25:c25:e004:f0c8
2022c19:dd:d9:dd:c25:c25:e004:f0c9/1282c19:dd:d9:dd:c25:c25:e004:f0c9
2032c19:dd:d9:dd:c25:c25:e004:f0ca/1282c19:dd:d9:dd:c25:c25:e004:f0ca
2042c19:dd:d9:dd:c25:c25:e004:f0cb/1282c19:dd:d9:dd:c25:c25:e004:f0cb
2052c19:dd:d9:dd:c25:c25:e004:f0cc/1282c19:dd:d9:dd:c25:c25:e004:f0cc
2062c19:dd:d9:dd:c25:c25:e004:f0cd/1282c19:dd:d9:dd:c25:c25:e004:f0cd
2072c19:dd:d9:dd:c25:c25:e004:f0ce/1282c19:dd:d9:dd:c25:c25:e004:f0ce
2082c19:dd:d9:dd:c25:c25:e004:f0cf/1282c19:dd:d9:dd:c25:c25:e004:f0cf
2092c19:dd:d9:dd:c25:c25:e004:f0d0/1282c19:dd:d9:dd:c25:c25:e004:f0d0
2102c19:dd:d9:dd:c25:c25:e004:f0d1/1282c19:dd:d9:dd:c25:c25:e004:f0d1
2112c19:dd:d9:dd:c25:c25:e004:f0d2/1282c19:dd:d9:dd:c25:c25:e004:f0d2
2122c19:dd:d9:dd:c25:c25:e004:f0d3/1282c19:dd:d9:dd:c25:c25:e004:f0d3
2132c19:dd:d9:dd:c25:c25:e004:f0d4/1282c19:dd:d9:dd:c25:c25:e004:f0d4
2142c19:dd:d9:dd:c25:c25:e004:f0d5/1282c19:dd:d9:dd:c25:c25:e004:f0d5
2152c19:dd:d9:dd:c25:c25:e004:f0d6/1282c19:dd:d9:dd:c25:c25:e004:f0d6
2162c19:dd:d9:dd:c25:c25:e004:f0d7/1282c19:dd:d9:dd:c25:c25:e004:f0d7
2172c19:dd:d9:dd:c25:c25:e004:f0d8/1282c19:dd:d9:dd:c25:c25:e004:f0d8
2182c19:dd:d9:dd:c25:c25:e004:f0d9/1282c19:dd:d9:dd:c25:c25:e004:f0d9
2192c19:dd:d9:dd:c25:c25:e004:f0da/1282c19:dd:d9:dd:c25:c25:e004:f0da
2202c19:dd:d9:dd:c25:c25:e004:f0db/1282c19:dd:d9:dd:c25:c25:e004:f0db
2212c19:dd:d9:dd:c25:c25:e004:f0dc/1282c19:dd:d9:dd:c25:c25:e004:f0dc
2222c19:dd:d9:dd:c25:c25:e004:f0dd/1282c19:dd:d9:dd:c25:c25:e004:f0dd
2232c19:dd:d9:dd:c25:c25:e004:f0de/1282c19:dd:d9:dd:c25:c25:e004:f0de
2242c19:dd:d9:dd:c25:c25:e004:f0df/1282c19:dd:d9:dd:c25:c25:e004:f0df
2252c19:dd:d9:dd:c25:c25:e004:f0e0/1282c19:dd:d9:dd:c25:c25:e004:f0e0
2262c19:dd:d9:dd:c25:c25:e004:f0e1/1282c19:dd:d9:dd:c25:c25:e004:f0e1
2272c19:dd:d9:dd:c25:c25:e004:f0e2/1282c19:dd:d9:dd:c25:c25:e004:f0e2
2282c19:dd:d9:dd:c25:c25:e004:f0e3/1282c19:dd:d9:dd:c25:c25:e004:f0e3
2292c19:dd:d9:dd:c25:c25:e004:f0e4/1282c19:dd:d9:dd:c25:c25:e004:f0e4
2302c19:dd:d9:dd:c25:c25:e004:f0e5/1282c19:dd:d9:dd:c25:c25:e004:f0e5
2312c19:dd:d9:dd:c25:c25:e004:f0e6/1282c19:dd:d9:dd:c25:c25:e004:f0e6
2322c19:dd:d9:dd:c25:c25:e004:f0e7/1282c19:dd:d9:dd:c25:c25:e004:f0e7
2332c19:dd:d9:dd:c25:c25:e004:f0e8/1282c19:dd:d9:dd:c25:c25:e004:f0e8
2342c19:dd:d9:dd:c25:c25:e004:f0e9/1282c19:dd:d9:dd:c25:c25:e004:f0e9
2352c19:dd:d9:dd:c25:c25:e004:f0ea/1282c19:dd:d9:dd:c25:c25:e004:f0ea
2362c19:dd:d9:dd:c25:c25:e004:f0eb/1282c19:dd:d9:dd:c25:c25:e004:f0eb
2372c19:dd:d9:dd:c25:c25:e004:f0ec/1282c19:dd:d9:dd:c25:c25:e004:f0ec
2382c19:dd:d9:dd:c25:c25:e004:f0ed/1282c19:dd:d9:dd:c25:c25:e004:f0ed
2392c19:dd:d9:dd:c25:c25:e004:f0ee/1282c19:dd:d9:dd:c25:c25:e004:f0ee
2402c19:dd:d9:dd:c25:c25:e004:f0ef/1282c19:dd:d9:dd:c25:c25:e004:f0ef
2412c19:dd:d9:dd:c25:c25:e004:f0f0/1282c19:dd:d9:dd:c25:c25:e004:f0f0
2422c19:dd:d9:dd:c25:c25:e004:f0f1/1282c19:dd:d9:dd:c25:c25:e004:f0f1
2432c19:dd:d9:dd:c25:c25:e004:f0f2/1282c19:dd:d9:dd:c25:c25:e004:f0f2
2442c19:dd:d9:dd:c25:c25:e004:f0f3/1282c19:dd:d9:dd:c25:c25:e004:f0f3
2452c19:dd:d9:dd:c25:c25:e004:f0f4/1282c19:dd:d9:dd:c25:c25:e004:f0f4
2462c19:dd:d9:dd:c25:c25:e004:f0f5/1282c19:dd:d9:dd:c25:c25:e004:f0f5
2472c19:dd:d9:dd:c25:c25:e004:f0f6/1282c19:dd:d9:dd:c25:c25:e004:f0f6
2482c19:dd:d9:dd:c25:c25:e004:f0f7/1282c19:dd:d9:dd:c25:c25:e004:f0f7
2492c19:dd:d9:dd:c25:c25:e004:f0f8/1282c19:dd:d9:dd:c25:c25:e004:f0f8
2502c19:dd:d9:dd:c25:c25:e004:f0f9/1282c19:dd:d9:dd:c25:c25:e004:f0f9
2512c19:dd:d9:dd:c25:c25:e004:f0fa/1282c19:dd:d9:dd:c25:c25:e004:f0fa
2522c19:dd:d9:dd:c25:c25:e004:f0fb/1282c19:dd:d9:dd:c25:c25:e004:f0fb
2532c19:dd:d9:dd:c25:c25:e004:f0fc/1282c19:dd:d9:dd:c25:c25:e004:f0fc
2542c19:dd:d9:dd:c25:c25:e004:f0fd/1282c19:dd:d9:dd:c25:c25:e004:f0fd
2552c19:dd:d9:dd:c25:c25:e004:f0fe/1282c19:dd:d9:dd:c25:c25:e004:f0fe
2562c19:dd:d9:dd:c25:c25:e004:f0ff/1282c19:dd:d9:dd:c25:c25:e004:f0ff

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.