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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/120
Addresses256
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25b:d00a:c900/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:c900
Last address
2c19:dd:d9:dd:c25:c25b:d00a:c9ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:c900
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.c.a.0.0.d.b.5.2.c.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
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25b:d00a:c900/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:c900/1282c19:dd:d9:dd:c25:c25b:d00a:c900
22c19:dd:d9:dd:c25:c25b:d00a:c901/1282c19:dd:d9:dd:c25:c25b:d00a:c901
32c19:dd:d9:dd:c25:c25b:d00a:c902/1282c19:dd:d9:dd:c25:c25b:d00a:c902
42c19:dd:d9:dd:c25:c25b:d00a:c903/1282c19:dd:d9:dd:c25:c25b:d00a:c903
52c19:dd:d9:dd:c25:c25b:d00a:c904/1282c19:dd:d9:dd:c25:c25b:d00a:c904
62c19:dd:d9:dd:c25:c25b:d00a:c905/1282c19:dd:d9:dd:c25:c25b:d00a:c905
72c19:dd:d9:dd:c25:c25b:d00a:c906/1282c19:dd:d9:dd:c25:c25b:d00a:c906
82c19:dd:d9:dd:c25:c25b:d00a:c907/1282c19:dd:d9:dd:c25:c25b:d00a:c907
92c19:dd:d9:dd:c25:c25b:d00a:c908/1282c19:dd:d9:dd:c25:c25b:d00a:c908
102c19:dd:d9:dd:c25:c25b:d00a:c909/1282c19:dd:d9:dd:c25:c25b:d00a:c909
112c19:dd:d9:dd:c25:c25b:d00a:c90a/1282c19:dd:d9:dd:c25:c25b:d00a:c90a
122c19:dd:d9:dd:c25:c25b:d00a:c90b/1282c19:dd:d9:dd:c25:c25b:d00a:c90b
132c19:dd:d9:dd:c25:c25b:d00a:c90c/1282c19:dd:d9:dd:c25:c25b:d00a:c90c
142c19:dd:d9:dd:c25:c25b:d00a:c90d/1282c19:dd:d9:dd:c25:c25b:d00a:c90d
152c19:dd:d9:dd:c25:c25b:d00a:c90e/1282c19:dd:d9:dd:c25:c25b:d00a:c90e
162c19:dd:d9:dd:c25:c25b:d00a:c90f/1282c19:dd:d9:dd:c25:c25b:d00a:c90f
172c19:dd:d9:dd:c25:c25b:d00a:c910/1282c19:dd:d9:dd:c25:c25b:d00a:c910
182c19:dd:d9:dd:c25:c25b:d00a:c911/1282c19:dd:d9:dd:c25:c25b:d00a:c911
192c19:dd:d9:dd:c25:c25b:d00a:c912/1282c19:dd:d9:dd:c25:c25b:d00a:c912
202c19:dd:d9:dd:c25:c25b:d00a:c913/1282c19:dd:d9:dd:c25:c25b:d00a:c913
212c19:dd:d9:dd:c25:c25b:d00a:c914/1282c19:dd:d9:dd:c25:c25b:d00a:c914
222c19:dd:d9:dd:c25:c25b:d00a:c915/1282c19:dd:d9:dd:c25:c25b:d00a:c915
232c19:dd:d9:dd:c25:c25b:d00a:c916/1282c19:dd:d9:dd:c25:c25b:d00a:c916
242c19:dd:d9:dd:c25:c25b:d00a:c917/1282c19:dd:d9:dd:c25:c25b:d00a:c917
252c19:dd:d9:dd:c25:c25b:d00a:c918/1282c19:dd:d9:dd:c25:c25b:d00a:c918
262c19:dd:d9:dd:c25:c25b:d00a:c919/1282c19:dd:d9:dd:c25:c25b:d00a:c919
272c19:dd:d9:dd:c25:c25b:d00a:c91a/1282c19:dd:d9:dd:c25:c25b:d00a:c91a
282c19:dd:d9:dd:c25:c25b:d00a:c91b/1282c19:dd:d9:dd:c25:c25b:d00a:c91b
292c19:dd:d9:dd:c25:c25b:d00a:c91c/1282c19:dd:d9:dd:c25:c25b:d00a:c91c
302c19:dd:d9:dd:c25:c25b:d00a:c91d/1282c19:dd:d9:dd:c25:c25b:d00a:c91d
312c19:dd:d9:dd:c25:c25b:d00a:c91e/1282c19:dd:d9:dd:c25:c25b:d00a:c91e
322c19:dd:d9:dd:c25:c25b:d00a:c91f/1282c19:dd:d9:dd:c25:c25b:d00a:c91f
332c19:dd:d9:dd:c25:c25b:d00a:c920/1282c19:dd:d9:dd:c25:c25b:d00a:c920
342c19:dd:d9:dd:c25:c25b:d00a:c921/1282c19:dd:d9:dd:c25:c25b:d00a:c921
352c19:dd:d9:dd:c25:c25b:d00a:c922/1282c19:dd:d9:dd:c25:c25b:d00a:c922
362c19:dd:d9:dd:c25:c25b:d00a:c923/1282c19:dd:d9:dd:c25:c25b:d00a:c923
372c19:dd:d9:dd:c25:c25b:d00a:c924/1282c19:dd:d9:dd:c25:c25b:d00a:c924
382c19:dd:d9:dd:c25:c25b:d00a:c925/1282c19:dd:d9:dd:c25:c25b:d00a:c925
392c19:dd:d9:dd:c25:c25b:d00a:c926/1282c19:dd:d9:dd:c25:c25b:d00a:c926
402c19:dd:d9:dd:c25:c25b:d00a:c927/1282c19:dd:d9:dd:c25:c25b:d00a:c927
412c19:dd:d9:dd:c25:c25b:d00a:c928/1282c19:dd:d9:dd:c25:c25b:d00a:c928
422c19:dd:d9:dd:c25:c25b:d00a:c929/1282c19:dd:d9:dd:c25:c25b:d00a:c929
432c19:dd:d9:dd:c25:c25b:d00a:c92a/1282c19:dd:d9:dd:c25:c25b:d00a:c92a
442c19:dd:d9:dd:c25:c25b:d00a:c92b/1282c19:dd:d9:dd:c25:c25b:d00a:c92b
452c19:dd:d9:dd:c25:c25b:d00a:c92c/1282c19:dd:d9:dd:c25:c25b:d00a:c92c
462c19:dd:d9:dd:c25:c25b:d00a:c92d/1282c19:dd:d9:dd:c25:c25b:d00a:c92d
472c19:dd:d9:dd:c25:c25b:d00a:c92e/1282c19:dd:d9:dd:c25:c25b:d00a:c92e
482c19:dd:d9:dd:c25:c25b:d00a:c92f/1282c19:dd:d9:dd:c25:c25b:d00a:c92f
492c19:dd:d9:dd:c25:c25b:d00a:c930/1282c19:dd:d9:dd:c25:c25b:d00a:c930
502c19:dd:d9:dd:c25:c25b:d00a:c931/1282c19:dd:d9:dd:c25:c25b:d00a:c931
512c19:dd:d9:dd:c25:c25b:d00a:c932/1282c19:dd:d9:dd:c25:c25b:d00a:c932
522c19:dd:d9:dd:c25:c25b:d00a:c933/1282c19:dd:d9:dd:c25:c25b:d00a:c933
532c19:dd:d9:dd:c25:c25b:d00a:c934/1282c19:dd:d9:dd:c25:c25b:d00a:c934
542c19:dd:d9:dd:c25:c25b:d00a:c935/1282c19:dd:d9:dd:c25:c25b:d00a:c935
552c19:dd:d9:dd:c25:c25b:d00a:c936/1282c19:dd:d9:dd:c25:c25b:d00a:c936
562c19:dd:d9:dd:c25:c25b:d00a:c937/1282c19:dd:d9:dd:c25:c25b:d00a:c937
572c19:dd:d9:dd:c25:c25b:d00a:c938/1282c19:dd:d9:dd:c25:c25b:d00a:c938
582c19:dd:d9:dd:c25:c25b:d00a:c939/1282c19:dd:d9:dd:c25:c25b:d00a:c939
592c19:dd:d9:dd:c25:c25b:d00a:c93a/1282c19:dd:d9:dd:c25:c25b:d00a:c93a
602c19:dd:d9:dd:c25:c25b:d00a:c93b/1282c19:dd:d9:dd:c25:c25b:d00a:c93b
612c19:dd:d9:dd:c25:c25b:d00a:c93c/1282c19:dd:d9:dd:c25:c25b:d00a:c93c
622c19:dd:d9:dd:c25:c25b:d00a:c93d/1282c19:dd:d9:dd:c25:c25b:d00a:c93d
632c19:dd:d9:dd:c25:c25b:d00a:c93e/1282c19:dd:d9:dd:c25:c25b:d00a:c93e
642c19:dd:d9:dd:c25:c25b:d00a:c93f/1282c19:dd:d9:dd:c25:c25b:d00a:c93f
652c19:dd:d9:dd:c25:c25b:d00a:c940/1282c19:dd:d9:dd:c25:c25b:d00a:c940
662c19:dd:d9:dd:c25:c25b:d00a:c941/1282c19:dd:d9:dd:c25:c25b:d00a:c941
672c19:dd:d9:dd:c25:c25b:d00a:c942/1282c19:dd:d9:dd:c25:c25b:d00a:c942
682c19:dd:d9:dd:c25:c25b:d00a:c943/1282c19:dd:d9:dd:c25:c25b:d00a:c943
692c19:dd:d9:dd:c25:c25b:d00a:c944/1282c19:dd:d9:dd:c25:c25b:d00a:c944
702c19:dd:d9:dd:c25:c25b:d00a:c945/1282c19:dd:d9:dd:c25:c25b:d00a:c945
712c19:dd:d9:dd:c25:c25b:d00a:c946/1282c19:dd:d9:dd:c25:c25b:d00a:c946
722c19:dd:d9:dd:c25:c25b:d00a:c947/1282c19:dd:d9:dd:c25:c25b:d00a:c947
732c19:dd:d9:dd:c25:c25b:d00a:c948/1282c19:dd:d9:dd:c25:c25b:d00a:c948
742c19:dd:d9:dd:c25:c25b:d00a:c949/1282c19:dd:d9:dd:c25:c25b:d00a:c949
752c19:dd:d9:dd:c25:c25b:d00a:c94a/1282c19:dd:d9:dd:c25:c25b:d00a:c94a
762c19:dd:d9:dd:c25:c25b:d00a:c94b/1282c19:dd:d9:dd:c25:c25b:d00a:c94b
772c19:dd:d9:dd:c25:c25b:d00a:c94c/1282c19:dd:d9:dd:c25:c25b:d00a:c94c
782c19:dd:d9:dd:c25:c25b:d00a:c94d/1282c19:dd:d9:dd:c25:c25b:d00a:c94d
792c19:dd:d9:dd:c25:c25b:d00a:c94e/1282c19:dd:d9:dd:c25:c25b:d00a:c94e
802c19:dd:d9:dd:c25:c25b:d00a:c94f/1282c19:dd:d9:dd:c25:c25b:d00a:c94f
812c19:dd:d9:dd:c25:c25b:d00a:c950/1282c19:dd:d9:dd:c25:c25b:d00a:c950
822c19:dd:d9:dd:c25:c25b:d00a:c951/1282c19:dd:d9:dd:c25:c25b:d00a:c951
832c19:dd:d9:dd:c25:c25b:d00a:c952/1282c19:dd:d9:dd:c25:c25b:d00a:c952
842c19:dd:d9:dd:c25:c25b:d00a:c953/1282c19:dd:d9:dd:c25:c25b:d00a:c953
852c19:dd:d9:dd:c25:c25b:d00a:c954/1282c19:dd:d9:dd:c25:c25b:d00a:c954
862c19:dd:d9:dd:c25:c25b:d00a:c955/1282c19:dd:d9:dd:c25:c25b:d00a:c955
872c19:dd:d9:dd:c25:c25b:d00a:c956/1282c19:dd:d9:dd:c25:c25b:d00a:c956
882c19:dd:d9:dd:c25:c25b:d00a:c957/1282c19:dd:d9:dd:c25:c25b:d00a:c957
892c19:dd:d9:dd:c25:c25b:d00a:c958/1282c19:dd:d9:dd:c25:c25b:d00a:c958
902c19:dd:d9:dd:c25:c25b:d00a:c959/1282c19:dd:d9:dd:c25:c25b:d00a:c959
912c19:dd:d9:dd:c25:c25b:d00a:c95a/1282c19:dd:d9:dd:c25:c25b:d00a:c95a
922c19:dd:d9:dd:c25:c25b:d00a:c95b/1282c19:dd:d9:dd:c25:c25b:d00a:c95b
932c19:dd:d9:dd:c25:c25b:d00a:c95c/1282c19:dd:d9:dd:c25:c25b:d00a:c95c
942c19:dd:d9:dd:c25:c25b:d00a:c95d/1282c19:dd:d9:dd:c25:c25b:d00a:c95d
952c19:dd:d9:dd:c25:c25b:d00a:c95e/1282c19:dd:d9:dd:c25:c25b:d00a:c95e
962c19:dd:d9:dd:c25:c25b:d00a:c95f/1282c19:dd:d9:dd:c25:c25b:d00a:c95f
972c19:dd:d9:dd:c25:c25b:d00a:c960/1282c19:dd:d9:dd:c25:c25b:d00a:c960
982c19:dd:d9:dd:c25:c25b:d00a:c961/1282c19:dd:d9:dd:c25:c25b:d00a:c961
992c19:dd:d9:dd:c25:c25b:d00a:c962/1282c19:dd:d9:dd:c25:c25b:d00a:c962
1002c19:dd:d9:dd:c25:c25b:d00a:c963/1282c19:dd:d9:dd:c25:c25b:d00a:c963
1012c19:dd:d9:dd:c25:c25b:d00a:c964/1282c19:dd:d9:dd:c25:c25b:d00a:c964
1022c19:dd:d9:dd:c25:c25b:d00a:c965/1282c19:dd:d9:dd:c25:c25b:d00a:c965
1032c19:dd:d9:dd:c25:c25b:d00a:c966/1282c19:dd:d9:dd:c25:c25b:d00a:c966
1042c19:dd:d9:dd:c25:c25b:d00a:c967/1282c19:dd:d9:dd:c25:c25b:d00a:c967
1052c19:dd:d9:dd:c25:c25b:d00a:c968/1282c19:dd:d9:dd:c25:c25b:d00a:c968
1062c19:dd:d9:dd:c25:c25b:d00a:c969/1282c19:dd:d9:dd:c25:c25b:d00a:c969
1072c19:dd:d9:dd:c25:c25b:d00a:c96a/1282c19:dd:d9:dd:c25:c25b:d00a:c96a
1082c19:dd:d9:dd:c25:c25b:d00a:c96b/1282c19:dd:d9:dd:c25:c25b:d00a:c96b
1092c19:dd:d9:dd:c25:c25b:d00a:c96c/1282c19:dd:d9:dd:c25:c25b:d00a:c96c
1102c19:dd:d9:dd:c25:c25b:d00a:c96d/1282c19:dd:d9:dd:c25:c25b:d00a:c96d
1112c19:dd:d9:dd:c25:c25b:d00a:c96e/1282c19:dd:d9:dd:c25:c25b:d00a:c96e
1122c19:dd:d9:dd:c25:c25b:d00a:c96f/1282c19:dd:d9:dd:c25:c25b:d00a:c96f
1132c19:dd:d9:dd:c25:c25b:d00a:c970/1282c19:dd:d9:dd:c25:c25b:d00a:c970
1142c19:dd:d9:dd:c25:c25b:d00a:c971/1282c19:dd:d9:dd:c25:c25b:d00a:c971
1152c19:dd:d9:dd:c25:c25b:d00a:c972/1282c19:dd:d9:dd:c25:c25b:d00a:c972
1162c19:dd:d9:dd:c25:c25b:d00a:c973/1282c19:dd:d9:dd:c25:c25b:d00a:c973
1172c19:dd:d9:dd:c25:c25b:d00a:c974/1282c19:dd:d9:dd:c25:c25b:d00a:c974
1182c19:dd:d9:dd:c25:c25b:d00a:c975/1282c19:dd:d9:dd:c25:c25b:d00a:c975
1192c19:dd:d9:dd:c25:c25b:d00a:c976/1282c19:dd:d9:dd:c25:c25b:d00a:c976
1202c19:dd:d9:dd:c25:c25b:d00a:c977/1282c19:dd:d9:dd:c25:c25b:d00a:c977
1212c19:dd:d9:dd:c25:c25b:d00a:c978/1282c19:dd:d9:dd:c25:c25b:d00a:c978
1222c19:dd:d9:dd:c25:c25b:d00a:c979/1282c19:dd:d9:dd:c25:c25b:d00a:c979
1232c19:dd:d9:dd:c25:c25b:d00a:c97a/1282c19:dd:d9:dd:c25:c25b:d00a:c97a
1242c19:dd:d9:dd:c25:c25b:d00a:c97b/1282c19:dd:d9:dd:c25:c25b:d00a:c97b
1252c19:dd:d9:dd:c25:c25b:d00a:c97c/1282c19:dd:d9:dd:c25:c25b:d00a:c97c
1262c19:dd:d9:dd:c25:c25b:d00a:c97d/1282c19:dd:d9:dd:c25:c25b:d00a:c97d
1272c19:dd:d9:dd:c25:c25b:d00a:c97e/1282c19:dd:d9:dd:c25:c25b:d00a:c97e
1282c19:dd:d9:dd:c25:c25b:d00a:c97f/1282c19:dd:d9:dd:c25:c25b:d00a:c97f
1292c19:dd:d9:dd:c25:c25b:d00a:c980/1282c19:dd:d9:dd:c25:c25b:d00a:c980
1302c19:dd:d9:dd:c25:c25b:d00a:c981/1282c19:dd:d9:dd:c25:c25b:d00a:c981
1312c19:dd:d9:dd:c25:c25b:d00a:c982/1282c19:dd:d9:dd:c25:c25b:d00a:c982
1322c19:dd:d9:dd:c25:c25b:d00a:c983/1282c19:dd:d9:dd:c25:c25b:d00a:c983
1332c19:dd:d9:dd:c25:c25b:d00a:c984/1282c19:dd:d9:dd:c25:c25b:d00a:c984
1342c19:dd:d9:dd:c25:c25b:d00a:c985/1282c19:dd:d9:dd:c25:c25b:d00a:c985
1352c19:dd:d9:dd:c25:c25b:d00a:c986/1282c19:dd:d9:dd:c25:c25b:d00a:c986
1362c19:dd:d9:dd:c25:c25b:d00a:c987/1282c19:dd:d9:dd:c25:c25b:d00a:c987
1372c19:dd:d9:dd:c25:c25b:d00a:c988/1282c19:dd:d9:dd:c25:c25b:d00a:c988
1382c19:dd:d9:dd:c25:c25b:d00a:c989/1282c19:dd:d9:dd:c25:c25b:d00a:c989
1392c19:dd:d9:dd:c25:c25b:d00a:c98a/1282c19:dd:d9:dd:c25:c25b:d00a:c98a
1402c19:dd:d9:dd:c25:c25b:d00a:c98b/1282c19:dd:d9:dd:c25:c25b:d00a:c98b
1412c19:dd:d9:dd:c25:c25b:d00a:c98c/1282c19:dd:d9:dd:c25:c25b:d00a:c98c
1422c19:dd:d9:dd:c25:c25b:d00a:c98d/1282c19:dd:d9:dd:c25:c25b:d00a:c98d
1432c19:dd:d9:dd:c25:c25b:d00a:c98e/1282c19:dd:d9:dd:c25:c25b:d00a:c98e
1442c19:dd:d9:dd:c25:c25b:d00a:c98f/1282c19:dd:d9:dd:c25:c25b:d00a:c98f
1452c19:dd:d9:dd:c25:c25b:d00a:c990/1282c19:dd:d9:dd:c25:c25b:d00a:c990
1462c19:dd:d9:dd:c25:c25b:d00a:c991/1282c19:dd:d9:dd:c25:c25b:d00a:c991
1472c19:dd:d9:dd:c25:c25b:d00a:c992/1282c19:dd:d9:dd:c25:c25b:d00a:c992
1482c19:dd:d9:dd:c25:c25b:d00a:c993/1282c19:dd:d9:dd:c25:c25b:d00a:c993
1492c19:dd:d9:dd:c25:c25b:d00a:c994/1282c19:dd:d9:dd:c25:c25b:d00a:c994
1502c19:dd:d9:dd:c25:c25b:d00a:c995/1282c19:dd:d9:dd:c25:c25b:d00a:c995
1512c19:dd:d9:dd:c25:c25b:d00a:c996/1282c19:dd:d9:dd:c25:c25b:d00a:c996
1522c19:dd:d9:dd:c25:c25b:d00a:c997/1282c19:dd:d9:dd:c25:c25b:d00a:c997
1532c19:dd:d9:dd:c25:c25b:d00a:c998/1282c19:dd:d9:dd:c25:c25b:d00a:c998
1542c19:dd:d9:dd:c25:c25b:d00a:c999/1282c19:dd:d9:dd:c25:c25b:d00a:c999
1552c19:dd:d9:dd:c25:c25b:d00a:c99a/1282c19:dd:d9:dd:c25:c25b:d00a:c99a
1562c19:dd:d9:dd:c25:c25b:d00a:c99b/1282c19:dd:d9:dd:c25:c25b:d00a:c99b
1572c19:dd:d9:dd:c25:c25b:d00a:c99c/1282c19:dd:d9:dd:c25:c25b:d00a:c99c
1582c19:dd:d9:dd:c25:c25b:d00a:c99d/1282c19:dd:d9:dd:c25:c25b:d00a:c99d
1592c19:dd:d9:dd:c25:c25b:d00a:c99e/1282c19:dd:d9:dd:c25:c25b:d00a:c99e
1602c19:dd:d9:dd:c25:c25b:d00a:c99f/1282c19:dd:d9:dd:c25:c25b:d00a:c99f
1612c19:dd:d9:dd:c25:c25b:d00a:c9a0/1282c19:dd:d9:dd:c25:c25b:d00a:c9a0
1622c19:dd:d9:dd:c25:c25b:d00a:c9a1/1282c19:dd:d9:dd:c25:c25b:d00a:c9a1
1632c19:dd:d9:dd:c25:c25b:d00a:c9a2/1282c19:dd:d9:dd:c25:c25b:d00a:c9a2
1642c19:dd:d9:dd:c25:c25b:d00a:c9a3/1282c19:dd:d9:dd:c25:c25b:d00a:c9a3
1652c19:dd:d9:dd:c25:c25b:d00a:c9a4/1282c19:dd:d9:dd:c25:c25b:d00a:c9a4
1662c19:dd:d9:dd:c25:c25b:d00a:c9a5/1282c19:dd:d9:dd:c25:c25b:d00a:c9a5
1672c19:dd:d9:dd:c25:c25b:d00a:c9a6/1282c19:dd:d9:dd:c25:c25b:d00a:c9a6
1682c19:dd:d9:dd:c25:c25b:d00a:c9a7/1282c19:dd:d9:dd:c25:c25b:d00a:c9a7
1692c19:dd:d9:dd:c25:c25b:d00a:c9a8/1282c19:dd:d9:dd:c25:c25b:d00a:c9a8
1702c19:dd:d9:dd:c25:c25b:d00a:c9a9/1282c19:dd:d9:dd:c25:c25b:d00a:c9a9
1712c19:dd:d9:dd:c25:c25b:d00a:c9aa/1282c19:dd:d9:dd:c25:c25b:d00a:c9aa
1722c19:dd:d9:dd:c25:c25b:d00a:c9ab/1282c19:dd:d9:dd:c25:c25b:d00a:c9ab
1732c19:dd:d9:dd:c25:c25b:d00a:c9ac/1282c19:dd:d9:dd:c25:c25b:d00a:c9ac
1742c19:dd:d9:dd:c25:c25b:d00a:c9ad/1282c19:dd:d9:dd:c25:c25b:d00a:c9ad
1752c19:dd:d9:dd:c25:c25b:d00a:c9ae/1282c19:dd:d9:dd:c25:c25b:d00a:c9ae
1762c19:dd:d9:dd:c25:c25b:d00a:c9af/1282c19:dd:d9:dd:c25:c25b:d00a:c9af
1772c19:dd:d9:dd:c25:c25b:d00a:c9b0/1282c19:dd:d9:dd:c25:c25b:d00a:c9b0
1782c19:dd:d9:dd:c25:c25b:d00a:c9b1/1282c19:dd:d9:dd:c25:c25b:d00a:c9b1
1792c19:dd:d9:dd:c25:c25b:d00a:c9b2/1282c19:dd:d9:dd:c25:c25b:d00a:c9b2
1802c19:dd:d9:dd:c25:c25b:d00a:c9b3/1282c19:dd:d9:dd:c25:c25b:d00a:c9b3
1812c19:dd:d9:dd:c25:c25b:d00a:c9b4/1282c19:dd:d9:dd:c25:c25b:d00a:c9b4
1822c19:dd:d9:dd:c25:c25b:d00a:c9b5/1282c19:dd:d9:dd:c25:c25b:d00a:c9b5
1832c19:dd:d9:dd:c25:c25b:d00a:c9b6/1282c19:dd:d9:dd:c25:c25b:d00a:c9b6
1842c19:dd:d9:dd:c25:c25b:d00a:c9b7/1282c19:dd:d9:dd:c25:c25b:d00a:c9b7
1852c19:dd:d9:dd:c25:c25b:d00a:c9b8/1282c19:dd:d9:dd:c25:c25b:d00a:c9b8
1862c19:dd:d9:dd:c25:c25b:d00a:c9b9/1282c19:dd:d9:dd:c25:c25b:d00a:c9b9
1872c19:dd:d9:dd:c25:c25b:d00a:c9ba/1282c19:dd:d9:dd:c25:c25b:d00a:c9ba
1882c19:dd:d9:dd:c25:c25b:d00a:c9bb/1282c19:dd:d9:dd:c25:c25b:d00a:c9bb
1892c19:dd:d9:dd:c25:c25b:d00a:c9bc/1282c19:dd:d9:dd:c25:c25b:d00a:c9bc
1902c19:dd:d9:dd:c25:c25b:d00a:c9bd/1282c19:dd:d9:dd:c25:c25b:d00a:c9bd
1912c19:dd:d9:dd:c25:c25b:d00a:c9be/1282c19:dd:d9:dd:c25:c25b:d00a:c9be
1922c19:dd:d9:dd:c25:c25b:d00a:c9bf/1282c19:dd:d9:dd:c25:c25b:d00a:c9bf
1932c19:dd:d9:dd:c25:c25b:d00a:c9c0/1282c19:dd:d9:dd:c25:c25b:d00a:c9c0
1942c19:dd:d9:dd:c25:c25b:d00a:c9c1/1282c19:dd:d9:dd:c25:c25b:d00a:c9c1
1952c19:dd:d9:dd:c25:c25b:d00a:c9c2/1282c19:dd:d9:dd:c25:c25b:d00a:c9c2
1962c19:dd:d9:dd:c25:c25b:d00a:c9c3/1282c19:dd:d9:dd:c25:c25b:d00a:c9c3
1972c19:dd:d9:dd:c25:c25b:d00a:c9c4/1282c19:dd:d9:dd:c25:c25b:d00a:c9c4
1982c19:dd:d9:dd:c25:c25b:d00a:c9c5/1282c19:dd:d9:dd:c25:c25b:d00a:c9c5
1992c19:dd:d9:dd:c25:c25b:d00a:c9c6/1282c19:dd:d9:dd:c25:c25b:d00a:c9c6
2002c19:dd:d9:dd:c25:c25b:d00a:c9c7/1282c19:dd:d9:dd:c25:c25b:d00a:c9c7
2012c19:dd:d9:dd:c25:c25b:d00a:c9c8/1282c19:dd:d9:dd:c25:c25b:d00a:c9c8
2022c19:dd:d9:dd:c25:c25b:d00a:c9c9/1282c19:dd:d9:dd:c25:c25b:d00a:c9c9
2032c19:dd:d9:dd:c25:c25b:d00a:c9ca/1282c19:dd:d9:dd:c25:c25b:d00a:c9ca
2042c19:dd:d9:dd:c25:c25b:d00a:c9cb/1282c19:dd:d9:dd:c25:c25b:d00a:c9cb
2052c19:dd:d9:dd:c25:c25b:d00a:c9cc/1282c19:dd:d9:dd:c25:c25b:d00a:c9cc
2062c19:dd:d9:dd:c25:c25b:d00a:c9cd/1282c19:dd:d9:dd:c25:c25b:d00a:c9cd
2072c19:dd:d9:dd:c25:c25b:d00a:c9ce/1282c19:dd:d9:dd:c25:c25b:d00a:c9ce
2082c19:dd:d9:dd:c25:c25b:d00a:c9cf/1282c19:dd:d9:dd:c25:c25b:d00a:c9cf
2092c19:dd:d9:dd:c25:c25b:d00a:c9d0/1282c19:dd:d9:dd:c25:c25b:d00a:c9d0
2102c19:dd:d9:dd:c25:c25b:d00a:c9d1/1282c19:dd:d9:dd:c25:c25b:d00a:c9d1
2112c19:dd:d9:dd:c25:c25b:d00a:c9d2/1282c19:dd:d9:dd:c25:c25b:d00a:c9d2
2122c19:dd:d9:dd:c25:c25b:d00a:c9d3/1282c19:dd:d9:dd:c25:c25b:d00a:c9d3
2132c19:dd:d9:dd:c25:c25b:d00a:c9d4/1282c19:dd:d9:dd:c25:c25b:d00a:c9d4
2142c19:dd:d9:dd:c25:c25b:d00a:c9d5/1282c19:dd:d9:dd:c25:c25b:d00a:c9d5
2152c19:dd:d9:dd:c25:c25b:d00a:c9d6/1282c19:dd:d9:dd:c25:c25b:d00a:c9d6
2162c19:dd:d9:dd:c25:c25b:d00a:c9d7/1282c19:dd:d9:dd:c25:c25b:d00a:c9d7
2172c19:dd:d9:dd:c25:c25b:d00a:c9d8/1282c19:dd:d9:dd:c25:c25b:d00a:c9d8
2182c19:dd:d9:dd:c25:c25b:d00a:c9d9/1282c19:dd:d9:dd:c25:c25b:d00a:c9d9
2192c19:dd:d9:dd:c25:c25b:d00a:c9da/1282c19:dd:d9:dd:c25:c25b:d00a:c9da
2202c19:dd:d9:dd:c25:c25b:d00a:c9db/1282c19:dd:d9:dd:c25:c25b:d00a:c9db
2212c19:dd:d9:dd:c25:c25b:d00a:c9dc/1282c19:dd:d9:dd:c25:c25b:d00a:c9dc
2222c19:dd:d9:dd:c25:c25b:d00a:c9dd/1282c19:dd:d9:dd:c25:c25b:d00a:c9dd
2232c19:dd:d9:dd:c25:c25b:d00a:c9de/1282c19:dd:d9:dd:c25:c25b:d00a:c9de
2242c19:dd:d9:dd:c25:c25b:d00a:c9df/1282c19:dd:d9:dd:c25:c25b:d00a:c9df
2252c19:dd:d9:dd:c25:c25b:d00a:c9e0/1282c19:dd:d9:dd:c25:c25b:d00a:c9e0
2262c19:dd:d9:dd:c25:c25b:d00a:c9e1/1282c19:dd:d9:dd:c25:c25b:d00a:c9e1
2272c19:dd:d9:dd:c25:c25b:d00a:c9e2/1282c19:dd:d9:dd:c25:c25b:d00a:c9e2
2282c19:dd:d9:dd:c25:c25b:d00a:c9e3/1282c19:dd:d9:dd:c25:c25b:d00a:c9e3
2292c19:dd:d9:dd:c25:c25b:d00a:c9e4/1282c19:dd:d9:dd:c25:c25b:d00a:c9e4
2302c19:dd:d9:dd:c25:c25b:d00a:c9e5/1282c19:dd:d9:dd:c25:c25b:d00a:c9e5
2312c19:dd:d9:dd:c25:c25b:d00a:c9e6/1282c19:dd:d9:dd:c25:c25b:d00a:c9e6
2322c19:dd:d9:dd:c25:c25b:d00a:c9e7/1282c19:dd:d9:dd:c25:c25b:d00a:c9e7
2332c19:dd:d9:dd:c25:c25b:d00a:c9e8/1282c19:dd:d9:dd:c25:c25b:d00a:c9e8
2342c19:dd:d9:dd:c25:c25b:d00a:c9e9/1282c19:dd:d9:dd:c25:c25b:d00a:c9e9
2352c19:dd:d9:dd:c25:c25b:d00a:c9ea/1282c19:dd:d9:dd:c25:c25b:d00a:c9ea
2362c19:dd:d9:dd:c25:c25b:d00a:c9eb/1282c19:dd:d9:dd:c25:c25b:d00a:c9eb
2372c19:dd:d9:dd:c25:c25b:d00a:c9ec/1282c19:dd:d9:dd:c25:c25b:d00a:c9ec
2382c19:dd:d9:dd:c25:c25b:d00a:c9ed/1282c19:dd:d9:dd:c25:c25b:d00a:c9ed
2392c19:dd:d9:dd:c25:c25b:d00a:c9ee/1282c19:dd:d9:dd:c25:c25b:d00a:c9ee
2402c19:dd:d9:dd:c25:c25b:d00a:c9ef/1282c19:dd:d9:dd:c25:c25b:d00a:c9ef
2412c19:dd:d9:dd:c25:c25b:d00a:c9f0/1282c19:dd:d9:dd:c25:c25b:d00a:c9f0
2422c19:dd:d9:dd:c25:c25b:d00a:c9f1/1282c19:dd:d9:dd:c25:c25b:d00a:c9f1
2432c19:dd:d9:dd:c25:c25b:d00a:c9f2/1282c19:dd:d9:dd:c25:c25b:d00a:c9f2
2442c19:dd:d9:dd:c25:c25b:d00a:c9f3/1282c19:dd:d9:dd:c25:c25b:d00a:c9f3
2452c19:dd:d9:dd:c25:c25b:d00a:c9f4/1282c19:dd:d9:dd:c25:c25b:d00a:c9f4
2462c19:dd:d9:dd:c25:c25b:d00a:c9f5/1282c19:dd:d9:dd:c25:c25b:d00a:c9f5
2472c19:dd:d9:dd:c25:c25b:d00a:c9f6/1282c19:dd:d9:dd:c25:c25b:d00a:c9f6
2482c19:dd:d9:dd:c25:c25b:d00a:c9f7/1282c19:dd:d9:dd:c25:c25b:d00a:c9f7
2492c19:dd:d9:dd:c25:c25b:d00a:c9f8/1282c19:dd:d9:dd:c25:c25b:d00a:c9f8
2502c19:dd:d9:dd:c25:c25b:d00a:c9f9/1282c19:dd:d9:dd:c25:c25b:d00a:c9f9
2512c19:dd:d9:dd:c25:c25b:d00a:c9fa/1282c19:dd:d9:dd:c25:c25b:d00a:c9fa
2522c19:dd:d9:dd:c25:c25b:d00a:c9fb/1282c19:dd:d9:dd:c25:c25b:d00a:c9fb
2532c19:dd:d9:dd:c25:c25b:d00a:c9fc/1282c19:dd:d9:dd:c25:c25b:d00a:c9fc
2542c19:dd:d9:dd:c25:c25b:d00a:c9fd/1282c19:dd:d9:dd:c25:c25b:d00a:c9fd
2552c19:dd:d9:dd:c25:c25b:d00a:c9fe/1282c19:dd:d9:dd:c25:c25b:d00a:c9fe
2562c19:dd:d9:dd:c25:c25b:d00a:c9ff/1282c19:dd:d9:dd:c25:c25b:d00a:c9ff

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.