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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:c25:8003:a000/116
First address
2c19:dd:d9:dd:c25:c25:8003:a000
Last address
2c19:dd:d9:dd:c25:c25:8003:afff
Addresses
4,096
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:8003:a000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
a.3.0.0.8.5.2.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:c25:8003:a000/116 makes 4,096 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:8003:a000/1282c19:dd:d9:dd:c25:c25:8003:a000
22c19:dd:d9:dd:c25:c25:8003:a001/1282c19:dd:d9:dd:c25:c25:8003:a001
32c19:dd:d9:dd:c25:c25:8003:a002/1282c19:dd:d9:dd:c25:c25:8003:a002
42c19:dd:d9:dd:c25:c25:8003:a003/1282c19:dd:d9:dd:c25:c25:8003:a003
52c19:dd:d9:dd:c25:c25:8003:a004/1282c19:dd:d9:dd:c25:c25:8003:a004
62c19:dd:d9:dd:c25:c25:8003:a005/1282c19:dd:d9:dd:c25:c25:8003:a005
72c19:dd:d9:dd:c25:c25:8003:a006/1282c19:dd:d9:dd:c25:c25:8003:a006
82c19:dd:d9:dd:c25:c25:8003:a007/1282c19:dd:d9:dd:c25:c25:8003:a007
92c19:dd:d9:dd:c25:c25:8003:a008/1282c19:dd:d9:dd:c25:c25:8003:a008
102c19:dd:d9:dd:c25:c25:8003:a009/1282c19:dd:d9:dd:c25:c25:8003:a009
112c19:dd:d9:dd:c25:c25:8003:a00a/1282c19:dd:d9:dd:c25:c25:8003:a00a
122c19:dd:d9:dd:c25:c25:8003:a00b/1282c19:dd:d9:dd:c25:c25:8003:a00b
132c19:dd:d9:dd:c25:c25:8003:a00c/1282c19:dd:d9:dd:c25:c25:8003:a00c
142c19:dd:d9:dd:c25:c25:8003:a00d/1282c19:dd:d9:dd:c25:c25:8003:a00d
152c19:dd:d9:dd:c25:c25:8003:a00e/1282c19:dd:d9:dd:c25:c25:8003:a00e
162c19:dd:d9:dd:c25:c25:8003:a00f/1282c19:dd:d9:dd:c25:c25:8003:a00f
172c19:dd:d9:dd:c25:c25:8003:a010/1282c19:dd:d9:dd:c25:c25:8003:a010
182c19:dd:d9:dd:c25:c25:8003:a011/1282c19:dd:d9:dd:c25:c25:8003:a011
192c19:dd:d9:dd:c25:c25:8003:a012/1282c19:dd:d9:dd:c25:c25:8003:a012
202c19:dd:d9:dd:c25:c25:8003:a013/1282c19:dd:d9:dd:c25:c25:8003:a013
212c19:dd:d9:dd:c25:c25:8003:a014/1282c19:dd:d9:dd:c25:c25:8003:a014
222c19:dd:d9:dd:c25:c25:8003:a015/1282c19:dd:d9:dd:c25:c25:8003:a015
232c19:dd:d9:dd:c25:c25:8003:a016/1282c19:dd:d9:dd:c25:c25:8003:a016
242c19:dd:d9:dd:c25:c25:8003:a017/1282c19:dd:d9:dd:c25:c25:8003:a017
252c19:dd:d9:dd:c25:c25:8003:a018/1282c19:dd:d9:dd:c25:c25:8003:a018
262c19:dd:d9:dd:c25:c25:8003:a019/1282c19:dd:d9:dd:c25:c25:8003:a019
272c19:dd:d9:dd:c25:c25:8003:a01a/1282c19:dd:d9:dd:c25:c25:8003:a01a
282c19:dd:d9:dd:c25:c25:8003:a01b/1282c19:dd:d9:dd:c25:c25:8003:a01b
292c19:dd:d9:dd:c25:c25:8003:a01c/1282c19:dd:d9:dd:c25:c25:8003:a01c
302c19:dd:d9:dd:c25:c25:8003:a01d/1282c19:dd:d9:dd:c25:c25:8003:a01d
312c19:dd:d9:dd:c25:c25:8003:a01e/1282c19:dd:d9:dd:c25:c25:8003:a01e
322c19:dd:d9:dd:c25:c25:8003:a01f/1282c19:dd:d9:dd:c25:c25:8003:a01f
332c19:dd:d9:dd:c25:c25:8003:a020/1282c19:dd:d9:dd:c25:c25:8003:a020
342c19:dd:d9:dd:c25:c25:8003:a021/1282c19:dd:d9:dd:c25:c25:8003:a021
352c19:dd:d9:dd:c25:c25:8003:a022/1282c19:dd:d9:dd:c25:c25:8003:a022
362c19:dd:d9:dd:c25:c25:8003:a023/1282c19:dd:d9:dd:c25:c25:8003:a023
372c19:dd:d9:dd:c25:c25:8003:a024/1282c19:dd:d9:dd:c25:c25:8003:a024
382c19:dd:d9:dd:c25:c25:8003:a025/1282c19:dd:d9:dd:c25:c25:8003:a025
392c19:dd:d9:dd:c25:c25:8003:a026/1282c19:dd:d9:dd:c25:c25:8003:a026
402c19:dd:d9:dd:c25:c25:8003:a027/1282c19:dd:d9:dd:c25:c25:8003:a027
412c19:dd:d9:dd:c25:c25:8003:a028/1282c19:dd:d9:dd:c25:c25:8003:a028
422c19:dd:d9:dd:c25:c25:8003:a029/1282c19:dd:d9:dd:c25:c25:8003:a029
432c19:dd:d9:dd:c25:c25:8003:a02a/1282c19:dd:d9:dd:c25:c25:8003:a02a
442c19:dd:d9:dd:c25:c25:8003:a02b/1282c19:dd:d9:dd:c25:c25:8003:a02b
452c19:dd:d9:dd:c25:c25:8003:a02c/1282c19:dd:d9:dd:c25:c25:8003:a02c
462c19:dd:d9:dd:c25:c25:8003:a02d/1282c19:dd:d9:dd:c25:c25:8003:a02d
472c19:dd:d9:dd:c25:c25:8003:a02e/1282c19:dd:d9:dd:c25:c25:8003:a02e
482c19:dd:d9:dd:c25:c25:8003:a02f/1282c19:dd:d9:dd:c25:c25:8003:a02f
492c19:dd:d9:dd:c25:c25:8003:a030/1282c19:dd:d9:dd:c25:c25:8003:a030
502c19:dd:d9:dd:c25:c25:8003:a031/1282c19:dd:d9:dd:c25:c25:8003:a031
512c19:dd:d9:dd:c25:c25:8003:a032/1282c19:dd:d9:dd:c25:c25:8003:a032
522c19:dd:d9:dd:c25:c25:8003:a033/1282c19:dd:d9:dd:c25:c25:8003:a033
532c19:dd:d9:dd:c25:c25:8003:a034/1282c19:dd:d9:dd:c25:c25:8003:a034
542c19:dd:d9:dd:c25:c25:8003:a035/1282c19:dd:d9:dd:c25:c25:8003:a035
552c19:dd:d9:dd:c25:c25:8003:a036/1282c19:dd:d9:dd:c25:c25:8003:a036
562c19:dd:d9:dd:c25:c25:8003:a037/1282c19:dd:d9:dd:c25:c25:8003:a037
572c19:dd:d9:dd:c25:c25:8003:a038/1282c19:dd:d9:dd:c25:c25:8003:a038
582c19:dd:d9:dd:c25:c25:8003:a039/1282c19:dd:d9:dd:c25:c25:8003:a039
592c19:dd:d9:dd:c25:c25:8003:a03a/1282c19:dd:d9:dd:c25:c25:8003:a03a
602c19:dd:d9:dd:c25:c25:8003:a03b/1282c19:dd:d9:dd:c25:c25:8003:a03b
612c19:dd:d9:dd:c25:c25:8003:a03c/1282c19:dd:d9:dd:c25:c25:8003:a03c
622c19:dd:d9:dd:c25:c25:8003:a03d/1282c19:dd:d9:dd:c25:c25:8003:a03d
632c19:dd:d9:dd:c25:c25:8003:a03e/1282c19:dd:d9:dd:c25:c25:8003:a03e
642c19:dd:d9:dd:c25:c25:8003:a03f/1282c19:dd:d9:dd:c25:c25:8003:a03f
652c19:dd:d9:dd:c25:c25:8003:a040/1282c19:dd:d9:dd:c25:c25:8003:a040
662c19:dd:d9:dd:c25:c25:8003:a041/1282c19:dd:d9:dd:c25:c25:8003:a041
672c19:dd:d9:dd:c25:c25:8003:a042/1282c19:dd:d9:dd:c25:c25:8003:a042
682c19:dd:d9:dd:c25:c25:8003:a043/1282c19:dd:d9:dd:c25:c25:8003:a043
692c19:dd:d9:dd:c25:c25:8003:a044/1282c19:dd:d9:dd:c25:c25:8003:a044
702c19:dd:d9:dd:c25:c25:8003:a045/1282c19:dd:d9:dd:c25:c25:8003:a045
712c19:dd:d9:dd:c25:c25:8003:a046/1282c19:dd:d9:dd:c25:c25:8003:a046
722c19:dd:d9:dd:c25:c25:8003:a047/1282c19:dd:d9:dd:c25:c25:8003:a047
732c19:dd:d9:dd:c25:c25:8003:a048/1282c19:dd:d9:dd:c25:c25:8003:a048
742c19:dd:d9:dd:c25:c25:8003:a049/1282c19:dd:d9:dd:c25:c25:8003:a049
752c19:dd:d9:dd:c25:c25:8003:a04a/1282c19:dd:d9:dd:c25:c25:8003:a04a
762c19:dd:d9:dd:c25:c25:8003:a04b/1282c19:dd:d9:dd:c25:c25:8003:a04b
772c19:dd:d9:dd:c25:c25:8003:a04c/1282c19:dd:d9:dd:c25:c25:8003:a04c
782c19:dd:d9:dd:c25:c25:8003:a04d/1282c19:dd:d9:dd:c25:c25:8003:a04d
792c19:dd:d9:dd:c25:c25:8003:a04e/1282c19:dd:d9:dd:c25:c25:8003:a04e
802c19:dd:d9:dd:c25:c25:8003:a04f/1282c19:dd:d9:dd:c25:c25:8003:a04f
812c19:dd:d9:dd:c25:c25:8003:a050/1282c19:dd:d9:dd:c25:c25:8003:a050
822c19:dd:d9:dd:c25:c25:8003:a051/1282c19:dd:d9:dd:c25:c25:8003:a051
832c19:dd:d9:dd:c25:c25:8003:a052/1282c19:dd:d9:dd:c25:c25:8003:a052
842c19:dd:d9:dd:c25:c25:8003:a053/1282c19:dd:d9:dd:c25:c25:8003:a053
852c19:dd:d9:dd:c25:c25:8003:a054/1282c19:dd:d9:dd:c25:c25:8003:a054
862c19:dd:d9:dd:c25:c25:8003:a055/1282c19:dd:d9:dd:c25:c25:8003:a055
872c19:dd:d9:dd:c25:c25:8003:a056/1282c19:dd:d9:dd:c25:c25:8003:a056
882c19:dd:d9:dd:c25:c25:8003:a057/1282c19:dd:d9:dd:c25:c25:8003:a057
892c19:dd:d9:dd:c25:c25:8003:a058/1282c19:dd:d9:dd:c25:c25:8003:a058
902c19:dd:d9:dd:c25:c25:8003:a059/1282c19:dd:d9:dd:c25:c25:8003:a059
912c19:dd:d9:dd:c25:c25:8003:a05a/1282c19:dd:d9:dd:c25:c25:8003:a05a
922c19:dd:d9:dd:c25:c25:8003:a05b/1282c19:dd:d9:dd:c25:c25:8003:a05b
932c19:dd:d9:dd:c25:c25:8003:a05c/1282c19:dd:d9:dd:c25:c25:8003:a05c
942c19:dd:d9:dd:c25:c25:8003:a05d/1282c19:dd:d9:dd:c25:c25:8003:a05d
952c19:dd:d9:dd:c25:c25:8003:a05e/1282c19:dd:d9:dd:c25:c25:8003:a05e
962c19:dd:d9:dd:c25:c25:8003:a05f/1282c19:dd:d9:dd:c25:c25:8003:a05f
972c19:dd:d9:dd:c25:c25:8003:a060/1282c19:dd:d9:dd:c25:c25:8003:a060
982c19:dd:d9:dd:c25:c25:8003:a061/1282c19:dd:d9:dd:c25:c25:8003:a061
992c19:dd:d9:dd:c25:c25:8003:a062/1282c19:dd:d9:dd:c25:c25:8003:a062
1002c19:dd:d9:dd:c25:c25:8003:a063/1282c19:dd:d9:dd:c25:c25:8003:a063
1012c19:dd:d9:dd:c25:c25:8003:a064/1282c19:dd:d9:dd:c25:c25:8003:a064
1022c19:dd:d9:dd:c25:c25:8003:a065/1282c19:dd:d9:dd:c25:c25:8003:a065
1032c19:dd:d9:dd:c25:c25:8003:a066/1282c19:dd:d9:dd:c25:c25:8003:a066
1042c19:dd:d9:dd:c25:c25:8003:a067/1282c19:dd:d9:dd:c25:c25:8003:a067
1052c19:dd:d9:dd:c25:c25:8003:a068/1282c19:dd:d9:dd:c25:c25:8003:a068
1062c19:dd:d9:dd:c25:c25:8003:a069/1282c19:dd:d9:dd:c25:c25:8003:a069
1072c19:dd:d9:dd:c25:c25:8003:a06a/1282c19:dd:d9:dd:c25:c25:8003:a06a
1082c19:dd:d9:dd:c25:c25:8003:a06b/1282c19:dd:d9:dd:c25:c25:8003:a06b
1092c19:dd:d9:dd:c25:c25:8003:a06c/1282c19:dd:d9:dd:c25:c25:8003:a06c
1102c19:dd:d9:dd:c25:c25:8003:a06d/1282c19:dd:d9:dd:c25:c25:8003:a06d
1112c19:dd:d9:dd:c25:c25:8003:a06e/1282c19:dd:d9:dd:c25:c25:8003:a06e
1122c19:dd:d9:dd:c25:c25:8003:a06f/1282c19:dd:d9:dd:c25:c25:8003:a06f
1132c19:dd:d9:dd:c25:c25:8003:a070/1282c19:dd:d9:dd:c25:c25:8003:a070
1142c19:dd:d9:dd:c25:c25:8003:a071/1282c19:dd:d9:dd:c25:c25:8003:a071
1152c19:dd:d9:dd:c25:c25:8003:a072/1282c19:dd:d9:dd:c25:c25:8003:a072
1162c19:dd:d9:dd:c25:c25:8003:a073/1282c19:dd:d9:dd:c25:c25:8003:a073
1172c19:dd:d9:dd:c25:c25:8003:a074/1282c19:dd:d9:dd:c25:c25:8003:a074
1182c19:dd:d9:dd:c25:c25:8003:a075/1282c19:dd:d9:dd:c25:c25:8003:a075
1192c19:dd:d9:dd:c25:c25:8003:a076/1282c19:dd:d9:dd:c25:c25:8003:a076
1202c19:dd:d9:dd:c25:c25:8003:a077/1282c19:dd:d9:dd:c25:c25:8003:a077
1212c19:dd:d9:dd:c25:c25:8003:a078/1282c19:dd:d9:dd:c25:c25:8003:a078
1222c19:dd:d9:dd:c25:c25:8003:a079/1282c19:dd:d9:dd:c25:c25:8003:a079
1232c19:dd:d9:dd:c25:c25:8003:a07a/1282c19:dd:d9:dd:c25:c25:8003:a07a
1242c19:dd:d9:dd:c25:c25:8003:a07b/1282c19:dd:d9:dd:c25:c25:8003:a07b
1252c19:dd:d9:dd:c25:c25:8003:a07c/1282c19:dd:d9:dd:c25:c25:8003:a07c
1262c19:dd:d9:dd:c25:c25:8003:a07d/1282c19:dd:d9:dd:c25:c25:8003:a07d
1272c19:dd:d9:dd:c25:c25:8003:a07e/1282c19:dd:d9:dd:c25:c25:8003:a07e
1282c19:dd:d9:dd:c25:c25:8003:a07f/1282c19:dd:d9:dd:c25:c25:8003:a07f
1292c19:dd:d9:dd:c25:c25:8003:a080/1282c19:dd:d9:dd:c25:c25:8003:a080
1302c19:dd:d9:dd:c25:c25:8003:a081/1282c19:dd:d9:dd:c25:c25:8003:a081
1312c19:dd:d9:dd:c25:c25:8003:a082/1282c19:dd:d9:dd:c25:c25:8003:a082
1322c19:dd:d9:dd:c25:c25:8003:a083/1282c19:dd:d9:dd:c25:c25:8003:a083
1332c19:dd:d9:dd:c25:c25:8003:a084/1282c19:dd:d9:dd:c25:c25:8003:a084
1342c19:dd:d9:dd:c25:c25:8003:a085/1282c19:dd:d9:dd:c25:c25:8003:a085
1352c19:dd:d9:dd:c25:c25:8003:a086/1282c19:dd:d9:dd:c25:c25:8003:a086
1362c19:dd:d9:dd:c25:c25:8003:a087/1282c19:dd:d9:dd:c25:c25:8003:a087
1372c19:dd:d9:dd:c25:c25:8003:a088/1282c19:dd:d9:dd:c25:c25:8003:a088
1382c19:dd:d9:dd:c25:c25:8003:a089/1282c19:dd:d9:dd:c25:c25:8003:a089
1392c19:dd:d9:dd:c25:c25:8003:a08a/1282c19:dd:d9:dd:c25:c25:8003:a08a
1402c19:dd:d9:dd:c25:c25:8003:a08b/1282c19:dd:d9:dd:c25:c25:8003:a08b
1412c19:dd:d9:dd:c25:c25:8003:a08c/1282c19:dd:d9:dd:c25:c25:8003:a08c
1422c19:dd:d9:dd:c25:c25:8003:a08d/1282c19:dd:d9:dd:c25:c25:8003:a08d
1432c19:dd:d9:dd:c25:c25:8003:a08e/1282c19:dd:d9:dd:c25:c25:8003:a08e
1442c19:dd:d9:dd:c25:c25:8003:a08f/1282c19:dd:d9:dd:c25:c25:8003:a08f
1452c19:dd:d9:dd:c25:c25:8003:a090/1282c19:dd:d9:dd:c25:c25:8003:a090
1462c19:dd:d9:dd:c25:c25:8003:a091/1282c19:dd:d9:dd:c25:c25:8003:a091
1472c19:dd:d9:dd:c25:c25:8003:a092/1282c19:dd:d9:dd:c25:c25:8003:a092
1482c19:dd:d9:dd:c25:c25:8003:a093/1282c19:dd:d9:dd:c25:c25:8003:a093
1492c19:dd:d9:dd:c25:c25:8003:a094/1282c19:dd:d9:dd:c25:c25:8003:a094
1502c19:dd:d9:dd:c25:c25:8003:a095/1282c19:dd:d9:dd:c25:c25:8003:a095
1512c19:dd:d9:dd:c25:c25:8003:a096/1282c19:dd:d9:dd:c25:c25:8003:a096
1522c19:dd:d9:dd:c25:c25:8003:a097/1282c19:dd:d9:dd:c25:c25:8003:a097
1532c19:dd:d9:dd:c25:c25:8003:a098/1282c19:dd:d9:dd:c25:c25:8003:a098
1542c19:dd:d9:dd:c25:c25:8003:a099/1282c19:dd:d9:dd:c25:c25:8003:a099
1552c19:dd:d9:dd:c25:c25:8003:a09a/1282c19:dd:d9:dd:c25:c25:8003:a09a
1562c19:dd:d9:dd:c25:c25:8003:a09b/1282c19:dd:d9:dd:c25:c25:8003:a09b
1572c19:dd:d9:dd:c25:c25:8003:a09c/1282c19:dd:d9:dd:c25:c25:8003:a09c
1582c19:dd:d9:dd:c25:c25:8003:a09d/1282c19:dd:d9:dd:c25:c25:8003:a09d
1592c19:dd:d9:dd:c25:c25:8003:a09e/1282c19:dd:d9:dd:c25:c25:8003:a09e
1602c19:dd:d9:dd:c25:c25:8003:a09f/1282c19:dd:d9:dd:c25:c25:8003:a09f
1612c19:dd:d9:dd:c25:c25:8003:a0a0/1282c19:dd:d9:dd:c25:c25:8003:a0a0
1622c19:dd:d9:dd:c25:c25:8003:a0a1/1282c19:dd:d9:dd:c25:c25:8003:a0a1
1632c19:dd:d9:dd:c25:c25:8003:a0a2/1282c19:dd:d9:dd:c25:c25:8003:a0a2
1642c19:dd:d9:dd:c25:c25:8003:a0a3/1282c19:dd:d9:dd:c25:c25:8003:a0a3
1652c19:dd:d9:dd:c25:c25:8003:a0a4/1282c19:dd:d9:dd:c25:c25:8003:a0a4
1662c19:dd:d9:dd:c25:c25:8003:a0a5/1282c19:dd:d9:dd:c25:c25:8003:a0a5
1672c19:dd:d9:dd:c25:c25:8003:a0a6/1282c19:dd:d9:dd:c25:c25:8003:a0a6
1682c19:dd:d9:dd:c25:c25:8003:a0a7/1282c19:dd:d9:dd:c25:c25:8003:a0a7
1692c19:dd:d9:dd:c25:c25:8003:a0a8/1282c19:dd:d9:dd:c25:c25:8003:a0a8
1702c19:dd:d9:dd:c25:c25:8003:a0a9/1282c19:dd:d9:dd:c25:c25:8003:a0a9
1712c19:dd:d9:dd:c25:c25:8003:a0aa/1282c19:dd:d9:dd:c25:c25:8003:a0aa
1722c19:dd:d9:dd:c25:c25:8003:a0ab/1282c19:dd:d9:dd:c25:c25:8003:a0ab
1732c19:dd:d9:dd:c25:c25:8003:a0ac/1282c19:dd:d9:dd:c25:c25:8003:a0ac
1742c19:dd:d9:dd:c25:c25:8003:a0ad/1282c19:dd:d9:dd:c25:c25:8003:a0ad
1752c19:dd:d9:dd:c25:c25:8003:a0ae/1282c19:dd:d9:dd:c25:c25:8003:a0ae
1762c19:dd:d9:dd:c25:c25:8003:a0af/1282c19:dd:d9:dd:c25:c25:8003:a0af
1772c19:dd:d9:dd:c25:c25:8003:a0b0/1282c19:dd:d9:dd:c25:c25:8003:a0b0
1782c19:dd:d9:dd:c25:c25:8003:a0b1/1282c19:dd:d9:dd:c25:c25:8003:a0b1
1792c19:dd:d9:dd:c25:c25:8003:a0b2/1282c19:dd:d9:dd:c25:c25:8003:a0b2
1802c19:dd:d9:dd:c25:c25:8003:a0b3/1282c19:dd:d9:dd:c25:c25:8003:a0b3
1812c19:dd:d9:dd:c25:c25:8003:a0b4/1282c19:dd:d9:dd:c25:c25:8003:a0b4
1822c19:dd:d9:dd:c25:c25:8003:a0b5/1282c19:dd:d9:dd:c25:c25:8003:a0b5
1832c19:dd:d9:dd:c25:c25:8003:a0b6/1282c19:dd:d9:dd:c25:c25:8003:a0b6
1842c19:dd:d9:dd:c25:c25:8003:a0b7/1282c19:dd:d9:dd:c25:c25:8003:a0b7
1852c19:dd:d9:dd:c25:c25:8003:a0b8/1282c19:dd:d9:dd:c25:c25:8003:a0b8
1862c19:dd:d9:dd:c25:c25:8003:a0b9/1282c19:dd:d9:dd:c25:c25:8003:a0b9
1872c19:dd:d9:dd:c25:c25:8003:a0ba/1282c19:dd:d9:dd:c25:c25:8003:a0ba
1882c19:dd:d9:dd:c25:c25:8003:a0bb/1282c19:dd:d9:dd:c25:c25:8003:a0bb
1892c19:dd:d9:dd:c25:c25:8003:a0bc/1282c19:dd:d9:dd:c25:c25:8003:a0bc
1902c19:dd:d9:dd:c25:c25:8003:a0bd/1282c19:dd:d9:dd:c25:c25:8003:a0bd
1912c19:dd:d9:dd:c25:c25:8003:a0be/1282c19:dd:d9:dd:c25:c25:8003:a0be
1922c19:dd:d9:dd:c25:c25:8003:a0bf/1282c19:dd:d9:dd:c25:c25:8003:a0bf
1932c19:dd:d9:dd:c25:c25:8003:a0c0/1282c19:dd:d9:dd:c25:c25:8003:a0c0
1942c19:dd:d9:dd:c25:c25:8003:a0c1/1282c19:dd:d9:dd:c25:c25:8003:a0c1
1952c19:dd:d9:dd:c25:c25:8003:a0c2/1282c19:dd:d9:dd:c25:c25:8003:a0c2
1962c19:dd:d9:dd:c25:c25:8003:a0c3/1282c19:dd:d9:dd:c25:c25:8003:a0c3
1972c19:dd:d9:dd:c25:c25:8003:a0c4/1282c19:dd:d9:dd:c25:c25:8003:a0c4
1982c19:dd:d9:dd:c25:c25:8003:a0c5/1282c19:dd:d9:dd:c25:c25:8003:a0c5
1992c19:dd:d9:dd:c25:c25:8003:a0c6/1282c19:dd:d9:dd:c25:c25:8003:a0c6
2002c19:dd:d9:dd:c25:c25:8003:a0c7/1282c19:dd:d9:dd:c25:c25:8003:a0c7
2012c19:dd:d9:dd:c25:c25:8003:a0c8/1282c19:dd:d9:dd:c25:c25:8003:a0c8
2022c19:dd:d9:dd:c25:c25:8003:a0c9/1282c19:dd:d9:dd:c25:c25:8003:a0c9
2032c19:dd:d9:dd:c25:c25:8003:a0ca/1282c19:dd:d9:dd:c25:c25:8003:a0ca
2042c19:dd:d9:dd:c25:c25:8003:a0cb/1282c19:dd:d9:dd:c25:c25:8003:a0cb
2052c19:dd:d9:dd:c25:c25:8003:a0cc/1282c19:dd:d9:dd:c25:c25:8003:a0cc
2062c19:dd:d9:dd:c25:c25:8003:a0cd/1282c19:dd:d9:dd:c25:c25:8003:a0cd
2072c19:dd:d9:dd:c25:c25:8003:a0ce/1282c19:dd:d9:dd:c25:c25:8003:a0ce
2082c19:dd:d9:dd:c25:c25:8003:a0cf/1282c19:dd:d9:dd:c25:c25:8003:a0cf
2092c19:dd:d9:dd:c25:c25:8003:a0d0/1282c19:dd:d9:dd:c25:c25:8003:a0d0
2102c19:dd:d9:dd:c25:c25:8003:a0d1/1282c19:dd:d9:dd:c25:c25:8003:a0d1
2112c19:dd:d9:dd:c25:c25:8003:a0d2/1282c19:dd:d9:dd:c25:c25:8003:a0d2
2122c19:dd:d9:dd:c25:c25:8003:a0d3/1282c19:dd:d9:dd:c25:c25:8003:a0d3
2132c19:dd:d9:dd:c25:c25:8003:a0d4/1282c19:dd:d9:dd:c25:c25:8003:a0d4
2142c19:dd:d9:dd:c25:c25:8003:a0d5/1282c19:dd:d9:dd:c25:c25:8003:a0d5
2152c19:dd:d9:dd:c25:c25:8003:a0d6/1282c19:dd:d9:dd:c25:c25:8003:a0d6
2162c19:dd:d9:dd:c25:c25:8003:a0d7/1282c19:dd:d9:dd:c25:c25:8003:a0d7
2172c19:dd:d9:dd:c25:c25:8003:a0d8/1282c19:dd:d9:dd:c25:c25:8003:a0d8
2182c19:dd:d9:dd:c25:c25:8003:a0d9/1282c19:dd:d9:dd:c25:c25:8003:a0d9
2192c19:dd:d9:dd:c25:c25:8003:a0da/1282c19:dd:d9:dd:c25:c25:8003:a0da
2202c19:dd:d9:dd:c25:c25:8003:a0db/1282c19:dd:d9:dd:c25:c25:8003:a0db
2212c19:dd:d9:dd:c25:c25:8003:a0dc/1282c19:dd:d9:dd:c25:c25:8003:a0dc
2222c19:dd:d9:dd:c25:c25:8003:a0dd/1282c19:dd:d9:dd:c25:c25:8003:a0dd
2232c19:dd:d9:dd:c25:c25:8003:a0de/1282c19:dd:d9:dd:c25:c25:8003:a0de
2242c19:dd:d9:dd:c25:c25:8003:a0df/1282c19:dd:d9:dd:c25:c25:8003:a0df
2252c19:dd:d9:dd:c25:c25:8003:a0e0/1282c19:dd:d9:dd:c25:c25:8003:a0e0
2262c19:dd:d9:dd:c25:c25:8003:a0e1/1282c19:dd:d9:dd:c25:c25:8003:a0e1
2272c19:dd:d9:dd:c25:c25:8003:a0e2/1282c19:dd:d9:dd:c25:c25:8003:a0e2
2282c19:dd:d9:dd:c25:c25:8003:a0e3/1282c19:dd:d9:dd:c25:c25:8003:a0e3
2292c19:dd:d9:dd:c25:c25:8003:a0e4/1282c19:dd:d9:dd:c25:c25:8003:a0e4
2302c19:dd:d9:dd:c25:c25:8003:a0e5/1282c19:dd:d9:dd:c25:c25:8003:a0e5
2312c19:dd:d9:dd:c25:c25:8003:a0e6/1282c19:dd:d9:dd:c25:c25:8003:a0e6
2322c19:dd:d9:dd:c25:c25:8003:a0e7/1282c19:dd:d9:dd:c25:c25:8003:a0e7
2332c19:dd:d9:dd:c25:c25:8003:a0e8/1282c19:dd:d9:dd:c25:c25:8003:a0e8
2342c19:dd:d9:dd:c25:c25:8003:a0e9/1282c19:dd:d9:dd:c25:c25:8003:a0e9
2352c19:dd:d9:dd:c25:c25:8003:a0ea/1282c19:dd:d9:dd:c25:c25:8003:a0ea
2362c19:dd:d9:dd:c25:c25:8003:a0eb/1282c19:dd:d9:dd:c25:c25:8003:a0eb
2372c19:dd:d9:dd:c25:c25:8003:a0ec/1282c19:dd:d9:dd:c25:c25:8003:a0ec
2382c19:dd:d9:dd:c25:c25:8003:a0ed/1282c19:dd:d9:dd:c25:c25:8003:a0ed
2392c19:dd:d9:dd:c25:c25:8003:a0ee/1282c19:dd:d9:dd:c25:c25:8003:a0ee
2402c19:dd:d9:dd:c25:c25:8003:a0ef/1282c19:dd:d9:dd:c25:c25:8003:a0ef
2412c19:dd:d9:dd:c25:c25:8003:a0f0/1282c19:dd:d9:dd:c25:c25:8003:a0f0
2422c19:dd:d9:dd:c25:c25:8003:a0f1/1282c19:dd:d9:dd:c25:c25:8003:a0f1
2432c19:dd:d9:dd:c25:c25:8003:a0f2/1282c19:dd:d9:dd:c25:c25:8003:a0f2
2442c19:dd:d9:dd:c25:c25:8003:a0f3/1282c19:dd:d9:dd:c25:c25:8003:a0f3
2452c19:dd:d9:dd:c25:c25:8003:a0f4/1282c19:dd:d9:dd:c25:c25:8003:a0f4
2462c19:dd:d9:dd:c25:c25:8003:a0f5/1282c19:dd:d9:dd:c25:c25:8003:a0f5
2472c19:dd:d9:dd:c25:c25:8003:a0f6/1282c19:dd:d9:dd:c25:c25:8003:a0f6
2482c19:dd:d9:dd:c25:c25:8003:a0f7/1282c19:dd:d9:dd:c25:c25:8003:a0f7
2492c19:dd:d9:dd:c25:c25:8003:a0f8/1282c19:dd:d9:dd:c25:c25:8003:a0f8
2502c19:dd:d9:dd:c25:c25:8003:a0f9/1282c19:dd:d9:dd:c25:c25:8003:a0f9
2512c19:dd:d9:dd:c25:c25:8003:a0fa/1282c19:dd:d9:dd:c25:c25:8003:a0fa
2522c19:dd:d9:dd:c25:c25:8003:a0fb/1282c19:dd:d9:dd:c25:c25:8003:a0fb
2532c19:dd:d9:dd:c25:c25:8003:a0fc/1282c19:dd:d9:dd:c25:c25:8003:a0fc
2542c19:dd:d9:dd:c25:c25:8003:a0fd/1282c19:dd:d9:dd:c25:c25:8003:a0fd
2552c19:dd:d9:dd:c25:c25:8003:a0fe/1282c19:dd:d9:dd:c25:c25:8003:a0fe
2562c19:dd:d9:dd:c25:c25:8003:a0ff/1282c19:dd:d9:dd:c25:c25:8003:a0ff

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.