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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:dd0:ec00:c25:c25:ddbf:d900/120
First address
2c19:dd:dd0:ec00:c25:c25:ddbf:d900
Last address
2c19:dd:dd0:ec00:c25:c25:ddbf:d9ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0dd0:ec00:0c25:0c25:ddbf:d900
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.d.f.b.d.d.5.2.c.0.5.2.c.0.0.0.c.e.0.d.d.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:dd0:ec00:c25:c25:ddbf:d900/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:dd0:ec00:c25:c25:ddbf:d900/1282c19:dd:dd0:ec00:c25:c25:ddbf:d900
22c19:dd:dd0:ec00:c25:c25:ddbf:d901/1282c19:dd:dd0:ec00:c25:c25:ddbf:d901
32c19:dd:dd0:ec00:c25:c25:ddbf:d902/1282c19:dd:dd0:ec00:c25:c25:ddbf:d902
42c19:dd:dd0:ec00:c25:c25:ddbf:d903/1282c19:dd:dd0:ec00:c25:c25:ddbf:d903
52c19:dd:dd0:ec00:c25:c25:ddbf:d904/1282c19:dd:dd0:ec00:c25:c25:ddbf:d904
62c19:dd:dd0:ec00:c25:c25:ddbf:d905/1282c19:dd:dd0:ec00:c25:c25:ddbf:d905
72c19:dd:dd0:ec00:c25:c25:ddbf:d906/1282c19:dd:dd0:ec00:c25:c25:ddbf:d906
82c19:dd:dd0:ec00:c25:c25:ddbf:d907/1282c19:dd:dd0:ec00:c25:c25:ddbf:d907
92c19:dd:dd0:ec00:c25:c25:ddbf:d908/1282c19:dd:dd0:ec00:c25:c25:ddbf:d908
102c19:dd:dd0:ec00:c25:c25:ddbf:d909/1282c19:dd:dd0:ec00:c25:c25:ddbf:d909
112c19:dd:dd0:ec00:c25:c25:ddbf:d90a/1282c19:dd:dd0:ec00:c25:c25:ddbf:d90a
122c19:dd:dd0:ec00:c25:c25:ddbf:d90b/1282c19:dd:dd0:ec00:c25:c25:ddbf:d90b
132c19:dd:dd0:ec00:c25:c25:ddbf:d90c/1282c19:dd:dd0:ec00:c25:c25:ddbf:d90c
142c19:dd:dd0:ec00:c25:c25:ddbf:d90d/1282c19:dd:dd0:ec00:c25:c25:ddbf:d90d
152c19:dd:dd0:ec00:c25:c25:ddbf:d90e/1282c19:dd:dd0:ec00:c25:c25:ddbf:d90e
162c19:dd:dd0:ec00:c25:c25:ddbf:d90f/1282c19:dd:dd0:ec00:c25:c25:ddbf:d90f
172c19:dd:dd0:ec00:c25:c25:ddbf:d910/1282c19:dd:dd0:ec00:c25:c25:ddbf:d910
182c19:dd:dd0:ec00:c25:c25:ddbf:d911/1282c19:dd:dd0:ec00:c25:c25:ddbf:d911
192c19:dd:dd0:ec00:c25:c25:ddbf:d912/1282c19:dd:dd0:ec00:c25:c25:ddbf:d912
202c19:dd:dd0:ec00:c25:c25:ddbf:d913/1282c19:dd:dd0:ec00:c25:c25:ddbf:d913
212c19:dd:dd0:ec00:c25:c25:ddbf:d914/1282c19:dd:dd0:ec00:c25:c25:ddbf:d914
222c19:dd:dd0:ec00:c25:c25:ddbf:d915/1282c19:dd:dd0:ec00:c25:c25:ddbf:d915
232c19:dd:dd0:ec00:c25:c25:ddbf:d916/1282c19:dd:dd0:ec00:c25:c25:ddbf:d916
242c19:dd:dd0:ec00:c25:c25:ddbf:d917/1282c19:dd:dd0:ec00:c25:c25:ddbf:d917
252c19:dd:dd0:ec00:c25:c25:ddbf:d918/1282c19:dd:dd0:ec00:c25:c25:ddbf:d918
262c19:dd:dd0:ec00:c25:c25:ddbf:d919/1282c19:dd:dd0:ec00:c25:c25:ddbf:d919
272c19:dd:dd0:ec00:c25:c25:ddbf:d91a/1282c19:dd:dd0:ec00:c25:c25:ddbf:d91a
282c19:dd:dd0:ec00:c25:c25:ddbf:d91b/1282c19:dd:dd0:ec00:c25:c25:ddbf:d91b
292c19:dd:dd0:ec00:c25:c25:ddbf:d91c/1282c19:dd:dd0:ec00:c25:c25:ddbf:d91c
302c19:dd:dd0:ec00:c25:c25:ddbf:d91d/1282c19:dd:dd0:ec00:c25:c25:ddbf:d91d
312c19:dd:dd0:ec00:c25:c25:ddbf:d91e/1282c19:dd:dd0:ec00:c25:c25:ddbf:d91e
322c19:dd:dd0:ec00:c25:c25:ddbf:d91f/1282c19:dd:dd0:ec00:c25:c25:ddbf:d91f
332c19:dd:dd0:ec00:c25:c25:ddbf:d920/1282c19:dd:dd0:ec00:c25:c25:ddbf:d920
342c19:dd:dd0:ec00:c25:c25:ddbf:d921/1282c19:dd:dd0:ec00:c25:c25:ddbf:d921
352c19:dd:dd0:ec00:c25:c25:ddbf:d922/1282c19:dd:dd0:ec00:c25:c25:ddbf:d922
362c19:dd:dd0:ec00:c25:c25:ddbf:d923/1282c19:dd:dd0:ec00:c25:c25:ddbf:d923
372c19:dd:dd0:ec00:c25:c25:ddbf:d924/1282c19:dd:dd0:ec00:c25:c25:ddbf:d924
382c19:dd:dd0:ec00:c25:c25:ddbf:d925/1282c19:dd:dd0:ec00:c25:c25:ddbf:d925
392c19:dd:dd0:ec00:c25:c25:ddbf:d926/1282c19:dd:dd0:ec00:c25:c25:ddbf:d926
402c19:dd:dd0:ec00:c25:c25:ddbf:d927/1282c19:dd:dd0:ec00:c25:c25:ddbf:d927
412c19:dd:dd0:ec00:c25:c25:ddbf:d928/1282c19:dd:dd0:ec00:c25:c25:ddbf:d928
422c19:dd:dd0:ec00:c25:c25:ddbf:d929/1282c19:dd:dd0:ec00:c25:c25:ddbf:d929
432c19:dd:dd0:ec00:c25:c25:ddbf:d92a/1282c19:dd:dd0:ec00:c25:c25:ddbf:d92a
442c19:dd:dd0:ec00:c25:c25:ddbf:d92b/1282c19:dd:dd0:ec00:c25:c25:ddbf:d92b
452c19:dd:dd0:ec00:c25:c25:ddbf:d92c/1282c19:dd:dd0:ec00:c25:c25:ddbf:d92c
462c19:dd:dd0:ec00:c25:c25:ddbf:d92d/1282c19:dd:dd0:ec00:c25:c25:ddbf:d92d
472c19:dd:dd0:ec00:c25:c25:ddbf:d92e/1282c19:dd:dd0:ec00:c25:c25:ddbf:d92e
482c19:dd:dd0:ec00:c25:c25:ddbf:d92f/1282c19:dd:dd0:ec00:c25:c25:ddbf:d92f
492c19:dd:dd0:ec00:c25:c25:ddbf:d930/1282c19:dd:dd0:ec00:c25:c25:ddbf:d930
502c19:dd:dd0:ec00:c25:c25:ddbf:d931/1282c19:dd:dd0:ec00:c25:c25:ddbf:d931
512c19:dd:dd0:ec00:c25:c25:ddbf:d932/1282c19:dd:dd0:ec00:c25:c25:ddbf:d932
522c19:dd:dd0:ec00:c25:c25:ddbf:d933/1282c19:dd:dd0:ec00:c25:c25:ddbf:d933
532c19:dd:dd0:ec00:c25:c25:ddbf:d934/1282c19:dd:dd0:ec00:c25:c25:ddbf:d934
542c19:dd:dd0:ec00:c25:c25:ddbf:d935/1282c19:dd:dd0:ec00:c25:c25:ddbf:d935
552c19:dd:dd0:ec00:c25:c25:ddbf:d936/1282c19:dd:dd0:ec00:c25:c25:ddbf:d936
562c19:dd:dd0:ec00:c25:c25:ddbf:d937/1282c19:dd:dd0:ec00:c25:c25:ddbf:d937
572c19:dd:dd0:ec00:c25:c25:ddbf:d938/1282c19:dd:dd0:ec00:c25:c25:ddbf:d938
582c19:dd:dd0:ec00:c25:c25:ddbf:d939/1282c19:dd:dd0:ec00:c25:c25:ddbf:d939
592c19:dd:dd0:ec00:c25:c25:ddbf:d93a/1282c19:dd:dd0:ec00:c25:c25:ddbf:d93a
602c19:dd:dd0:ec00:c25:c25:ddbf:d93b/1282c19:dd:dd0:ec00:c25:c25:ddbf:d93b
612c19:dd:dd0:ec00:c25:c25:ddbf:d93c/1282c19:dd:dd0:ec00:c25:c25:ddbf:d93c
622c19:dd:dd0:ec00:c25:c25:ddbf:d93d/1282c19:dd:dd0:ec00:c25:c25:ddbf:d93d
632c19:dd:dd0:ec00:c25:c25:ddbf:d93e/1282c19:dd:dd0:ec00:c25:c25:ddbf:d93e
642c19:dd:dd0:ec00:c25:c25:ddbf:d93f/1282c19:dd:dd0:ec00:c25:c25:ddbf:d93f
652c19:dd:dd0:ec00:c25:c25:ddbf:d940/1282c19:dd:dd0:ec00:c25:c25:ddbf:d940
662c19:dd:dd0:ec00:c25:c25:ddbf:d941/1282c19:dd:dd0:ec00:c25:c25:ddbf:d941
672c19:dd:dd0:ec00:c25:c25:ddbf:d942/1282c19:dd:dd0:ec00:c25:c25:ddbf:d942
682c19:dd:dd0:ec00:c25:c25:ddbf:d943/1282c19:dd:dd0:ec00:c25:c25:ddbf:d943
692c19:dd:dd0:ec00:c25:c25:ddbf:d944/1282c19:dd:dd0:ec00:c25:c25:ddbf:d944
702c19:dd:dd0:ec00:c25:c25:ddbf:d945/1282c19:dd:dd0:ec00:c25:c25:ddbf:d945
712c19:dd:dd0:ec00:c25:c25:ddbf:d946/1282c19:dd:dd0:ec00:c25:c25:ddbf:d946
722c19:dd:dd0:ec00:c25:c25:ddbf:d947/1282c19:dd:dd0:ec00:c25:c25:ddbf:d947
732c19:dd:dd0:ec00:c25:c25:ddbf:d948/1282c19:dd:dd0:ec00:c25:c25:ddbf:d948
742c19:dd:dd0:ec00:c25:c25:ddbf:d949/1282c19:dd:dd0:ec00:c25:c25:ddbf:d949
752c19:dd:dd0:ec00:c25:c25:ddbf:d94a/1282c19:dd:dd0:ec00:c25:c25:ddbf:d94a
762c19:dd:dd0:ec00:c25:c25:ddbf:d94b/1282c19:dd:dd0:ec00:c25:c25:ddbf:d94b
772c19:dd:dd0:ec00:c25:c25:ddbf:d94c/1282c19:dd:dd0:ec00:c25:c25:ddbf:d94c
782c19:dd:dd0:ec00:c25:c25:ddbf:d94d/1282c19:dd:dd0:ec00:c25:c25:ddbf:d94d
792c19:dd:dd0:ec00:c25:c25:ddbf:d94e/1282c19:dd:dd0:ec00:c25:c25:ddbf:d94e
802c19:dd:dd0:ec00:c25:c25:ddbf:d94f/1282c19:dd:dd0:ec00:c25:c25:ddbf:d94f
812c19:dd:dd0:ec00:c25:c25:ddbf:d950/1282c19:dd:dd0:ec00:c25:c25:ddbf:d950
822c19:dd:dd0:ec00:c25:c25:ddbf:d951/1282c19:dd:dd0:ec00:c25:c25:ddbf:d951
832c19:dd:dd0:ec00:c25:c25:ddbf:d952/1282c19:dd:dd0:ec00:c25:c25:ddbf:d952
842c19:dd:dd0:ec00:c25:c25:ddbf:d953/1282c19:dd:dd0:ec00:c25:c25:ddbf:d953
852c19:dd:dd0:ec00:c25:c25:ddbf:d954/1282c19:dd:dd0:ec00:c25:c25:ddbf:d954
862c19:dd:dd0:ec00:c25:c25:ddbf:d955/1282c19:dd:dd0:ec00:c25:c25:ddbf:d955
872c19:dd:dd0:ec00:c25:c25:ddbf:d956/1282c19:dd:dd0:ec00:c25:c25:ddbf:d956
882c19:dd:dd0:ec00:c25:c25:ddbf:d957/1282c19:dd:dd0:ec00:c25:c25:ddbf:d957
892c19:dd:dd0:ec00:c25:c25:ddbf:d958/1282c19:dd:dd0:ec00:c25:c25:ddbf:d958
902c19:dd:dd0:ec00:c25:c25:ddbf:d959/1282c19:dd:dd0:ec00:c25:c25:ddbf:d959
912c19:dd:dd0:ec00:c25:c25:ddbf:d95a/1282c19:dd:dd0:ec00:c25:c25:ddbf:d95a
922c19:dd:dd0:ec00:c25:c25:ddbf:d95b/1282c19:dd:dd0:ec00:c25:c25:ddbf:d95b
932c19:dd:dd0:ec00:c25:c25:ddbf:d95c/1282c19:dd:dd0:ec00:c25:c25:ddbf:d95c
942c19:dd:dd0:ec00:c25:c25:ddbf:d95d/1282c19:dd:dd0:ec00:c25:c25:ddbf:d95d
952c19:dd:dd0:ec00:c25:c25:ddbf:d95e/1282c19:dd:dd0:ec00:c25:c25:ddbf:d95e
962c19:dd:dd0:ec00:c25:c25:ddbf:d95f/1282c19:dd:dd0:ec00:c25:c25:ddbf:d95f
972c19:dd:dd0:ec00:c25:c25:ddbf:d960/1282c19:dd:dd0:ec00:c25:c25:ddbf:d960
982c19:dd:dd0:ec00:c25:c25:ddbf:d961/1282c19:dd:dd0:ec00:c25:c25:ddbf:d961
992c19:dd:dd0:ec00:c25:c25:ddbf:d962/1282c19:dd:dd0:ec00:c25:c25:ddbf:d962
1002c19:dd:dd0:ec00:c25:c25:ddbf:d963/1282c19:dd:dd0:ec00:c25:c25:ddbf:d963
1012c19:dd:dd0:ec00:c25:c25:ddbf:d964/1282c19:dd:dd0:ec00:c25:c25:ddbf:d964
1022c19:dd:dd0:ec00:c25:c25:ddbf:d965/1282c19:dd:dd0:ec00:c25:c25:ddbf:d965
1032c19:dd:dd0:ec00:c25:c25:ddbf:d966/1282c19:dd:dd0:ec00:c25:c25:ddbf:d966
1042c19:dd:dd0:ec00:c25:c25:ddbf:d967/1282c19:dd:dd0:ec00:c25:c25:ddbf:d967
1052c19:dd:dd0:ec00:c25:c25:ddbf:d968/1282c19:dd:dd0:ec00:c25:c25:ddbf:d968
1062c19:dd:dd0:ec00:c25:c25:ddbf:d969/1282c19:dd:dd0:ec00:c25:c25:ddbf:d969
1072c19:dd:dd0:ec00:c25:c25:ddbf:d96a/1282c19:dd:dd0:ec00:c25:c25:ddbf:d96a
1082c19:dd:dd0:ec00:c25:c25:ddbf:d96b/1282c19:dd:dd0:ec00:c25:c25:ddbf:d96b
1092c19:dd:dd0:ec00:c25:c25:ddbf:d96c/1282c19:dd:dd0:ec00:c25:c25:ddbf:d96c
1102c19:dd:dd0:ec00:c25:c25:ddbf:d96d/1282c19:dd:dd0:ec00:c25:c25:ddbf:d96d
1112c19:dd:dd0:ec00:c25:c25:ddbf:d96e/1282c19:dd:dd0:ec00:c25:c25:ddbf:d96e
1122c19:dd:dd0:ec00:c25:c25:ddbf:d96f/1282c19:dd:dd0:ec00:c25:c25:ddbf:d96f
1132c19:dd:dd0:ec00:c25:c25:ddbf:d970/1282c19:dd:dd0:ec00:c25:c25:ddbf:d970
1142c19:dd:dd0:ec00:c25:c25:ddbf:d971/1282c19:dd:dd0:ec00:c25:c25:ddbf:d971
1152c19:dd:dd0:ec00:c25:c25:ddbf:d972/1282c19:dd:dd0:ec00:c25:c25:ddbf:d972
1162c19:dd:dd0:ec00:c25:c25:ddbf:d973/1282c19:dd:dd0:ec00:c25:c25:ddbf:d973
1172c19:dd:dd0:ec00:c25:c25:ddbf:d974/1282c19:dd:dd0:ec00:c25:c25:ddbf:d974
1182c19:dd:dd0:ec00:c25:c25:ddbf:d975/1282c19:dd:dd0:ec00:c25:c25:ddbf:d975
1192c19:dd:dd0:ec00:c25:c25:ddbf:d976/1282c19:dd:dd0:ec00:c25:c25:ddbf:d976
1202c19:dd:dd0:ec00:c25:c25:ddbf:d977/1282c19:dd:dd0:ec00:c25:c25:ddbf:d977
1212c19:dd:dd0:ec00:c25:c25:ddbf:d978/1282c19:dd:dd0:ec00:c25:c25:ddbf:d978
1222c19:dd:dd0:ec00:c25:c25:ddbf:d979/1282c19:dd:dd0:ec00:c25:c25:ddbf:d979
1232c19:dd:dd0:ec00:c25:c25:ddbf:d97a/1282c19:dd:dd0:ec00:c25:c25:ddbf:d97a
1242c19:dd:dd0:ec00:c25:c25:ddbf:d97b/1282c19:dd:dd0:ec00:c25:c25:ddbf:d97b
1252c19:dd:dd0:ec00:c25:c25:ddbf:d97c/1282c19:dd:dd0:ec00:c25:c25:ddbf:d97c
1262c19:dd:dd0:ec00:c25:c25:ddbf:d97d/1282c19:dd:dd0:ec00:c25:c25:ddbf:d97d
1272c19:dd:dd0:ec00:c25:c25:ddbf:d97e/1282c19:dd:dd0:ec00:c25:c25:ddbf:d97e
1282c19:dd:dd0:ec00:c25:c25:ddbf:d97f/1282c19:dd:dd0:ec00:c25:c25:ddbf:d97f
1292c19:dd:dd0:ec00:c25:c25:ddbf:d980/1282c19:dd:dd0:ec00:c25:c25:ddbf:d980
1302c19:dd:dd0:ec00:c25:c25:ddbf:d981/1282c19:dd:dd0:ec00:c25:c25:ddbf:d981
1312c19:dd:dd0:ec00:c25:c25:ddbf:d982/1282c19:dd:dd0:ec00:c25:c25:ddbf:d982
1322c19:dd:dd0:ec00:c25:c25:ddbf:d983/1282c19:dd:dd0:ec00:c25:c25:ddbf:d983
1332c19:dd:dd0:ec00:c25:c25:ddbf:d984/1282c19:dd:dd0:ec00:c25:c25:ddbf:d984
1342c19:dd:dd0:ec00:c25:c25:ddbf:d985/1282c19:dd:dd0:ec00:c25:c25:ddbf:d985
1352c19:dd:dd0:ec00:c25:c25:ddbf:d986/1282c19:dd:dd0:ec00:c25:c25:ddbf:d986
1362c19:dd:dd0:ec00:c25:c25:ddbf:d987/1282c19:dd:dd0:ec00:c25:c25:ddbf:d987
1372c19:dd:dd0:ec00:c25:c25:ddbf:d988/1282c19:dd:dd0:ec00:c25:c25:ddbf:d988
1382c19:dd:dd0:ec00:c25:c25:ddbf:d989/1282c19:dd:dd0:ec00:c25:c25:ddbf:d989
1392c19:dd:dd0:ec00:c25:c25:ddbf:d98a/1282c19:dd:dd0:ec00:c25:c25:ddbf:d98a
1402c19:dd:dd0:ec00:c25:c25:ddbf:d98b/1282c19:dd:dd0:ec00:c25:c25:ddbf:d98b
1412c19:dd:dd0:ec00:c25:c25:ddbf:d98c/1282c19:dd:dd0:ec00:c25:c25:ddbf:d98c
1422c19:dd:dd0:ec00:c25:c25:ddbf:d98d/1282c19:dd:dd0:ec00:c25:c25:ddbf:d98d
1432c19:dd:dd0:ec00:c25:c25:ddbf:d98e/1282c19:dd:dd0:ec00:c25:c25:ddbf:d98e
1442c19:dd:dd0:ec00:c25:c25:ddbf:d98f/1282c19:dd:dd0:ec00:c25:c25:ddbf:d98f
1452c19:dd:dd0:ec00:c25:c25:ddbf:d990/1282c19:dd:dd0:ec00:c25:c25:ddbf:d990
1462c19:dd:dd0:ec00:c25:c25:ddbf:d991/1282c19:dd:dd0:ec00:c25:c25:ddbf:d991
1472c19:dd:dd0:ec00:c25:c25:ddbf:d992/1282c19:dd:dd0:ec00:c25:c25:ddbf:d992
1482c19:dd:dd0:ec00:c25:c25:ddbf:d993/1282c19:dd:dd0:ec00:c25:c25:ddbf:d993
1492c19:dd:dd0:ec00:c25:c25:ddbf:d994/1282c19:dd:dd0:ec00:c25:c25:ddbf:d994
1502c19:dd:dd0:ec00:c25:c25:ddbf:d995/1282c19:dd:dd0:ec00:c25:c25:ddbf:d995
1512c19:dd:dd0:ec00:c25:c25:ddbf:d996/1282c19:dd:dd0:ec00:c25:c25:ddbf:d996
1522c19:dd:dd0:ec00:c25:c25:ddbf:d997/1282c19:dd:dd0:ec00:c25:c25:ddbf:d997
1532c19:dd:dd0:ec00:c25:c25:ddbf:d998/1282c19:dd:dd0:ec00:c25:c25:ddbf:d998
1542c19:dd:dd0:ec00:c25:c25:ddbf:d999/1282c19:dd:dd0:ec00:c25:c25:ddbf:d999
1552c19:dd:dd0:ec00:c25:c25:ddbf:d99a/1282c19:dd:dd0:ec00:c25:c25:ddbf:d99a
1562c19:dd:dd0:ec00:c25:c25:ddbf:d99b/1282c19:dd:dd0:ec00:c25:c25:ddbf:d99b
1572c19:dd:dd0:ec00:c25:c25:ddbf:d99c/1282c19:dd:dd0:ec00:c25:c25:ddbf:d99c
1582c19:dd:dd0:ec00:c25:c25:ddbf:d99d/1282c19:dd:dd0:ec00:c25:c25:ddbf:d99d
1592c19:dd:dd0:ec00:c25:c25:ddbf:d99e/1282c19:dd:dd0:ec00:c25:c25:ddbf:d99e
1602c19:dd:dd0:ec00:c25:c25:ddbf:d99f/1282c19:dd:dd0:ec00:c25:c25:ddbf:d99f
1612c19:dd:dd0:ec00:c25:c25:ddbf:d9a0/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9a0
1622c19:dd:dd0:ec00:c25:c25:ddbf:d9a1/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9a1
1632c19:dd:dd0:ec00:c25:c25:ddbf:d9a2/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9a2
1642c19:dd:dd0:ec00:c25:c25:ddbf:d9a3/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9a3
1652c19:dd:dd0:ec00:c25:c25:ddbf:d9a4/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9a4
1662c19:dd:dd0:ec00:c25:c25:ddbf:d9a5/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9a5
1672c19:dd:dd0:ec00:c25:c25:ddbf:d9a6/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9a6
1682c19:dd:dd0:ec00:c25:c25:ddbf:d9a7/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9a7
1692c19:dd:dd0:ec00:c25:c25:ddbf:d9a8/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9a8
1702c19:dd:dd0:ec00:c25:c25:ddbf:d9a9/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9a9
1712c19:dd:dd0:ec00:c25:c25:ddbf:d9aa/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9aa
1722c19:dd:dd0:ec00:c25:c25:ddbf:d9ab/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9ab
1732c19:dd:dd0:ec00:c25:c25:ddbf:d9ac/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9ac
1742c19:dd:dd0:ec00:c25:c25:ddbf:d9ad/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9ad
1752c19:dd:dd0:ec00:c25:c25:ddbf:d9ae/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9ae
1762c19:dd:dd0:ec00:c25:c25:ddbf:d9af/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9af
1772c19:dd:dd0:ec00:c25:c25:ddbf:d9b0/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9b0
1782c19:dd:dd0:ec00:c25:c25:ddbf:d9b1/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9b1
1792c19:dd:dd0:ec00:c25:c25:ddbf:d9b2/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9b2
1802c19:dd:dd0:ec00:c25:c25:ddbf:d9b3/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9b3
1812c19:dd:dd0:ec00:c25:c25:ddbf:d9b4/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9b4
1822c19:dd:dd0:ec00:c25:c25:ddbf:d9b5/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9b5
1832c19:dd:dd0:ec00:c25:c25:ddbf:d9b6/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9b6
1842c19:dd:dd0:ec00:c25:c25:ddbf:d9b7/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9b7
1852c19:dd:dd0:ec00:c25:c25:ddbf:d9b8/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9b8
1862c19:dd:dd0:ec00:c25:c25:ddbf:d9b9/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9b9
1872c19:dd:dd0:ec00:c25:c25:ddbf:d9ba/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9ba
1882c19:dd:dd0:ec00:c25:c25:ddbf:d9bb/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9bb
1892c19:dd:dd0:ec00:c25:c25:ddbf:d9bc/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9bc
1902c19:dd:dd0:ec00:c25:c25:ddbf:d9bd/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9bd
1912c19:dd:dd0:ec00:c25:c25:ddbf:d9be/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9be
1922c19:dd:dd0:ec00:c25:c25:ddbf:d9bf/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9bf
1932c19:dd:dd0:ec00:c25:c25:ddbf:d9c0/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9c0
1942c19:dd:dd0:ec00:c25:c25:ddbf:d9c1/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9c1
1952c19:dd:dd0:ec00:c25:c25:ddbf:d9c2/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9c2
1962c19:dd:dd0:ec00:c25:c25:ddbf:d9c3/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9c3
1972c19:dd:dd0:ec00:c25:c25:ddbf:d9c4/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9c4
1982c19:dd:dd0:ec00:c25:c25:ddbf:d9c5/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9c5
1992c19:dd:dd0:ec00:c25:c25:ddbf:d9c6/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9c6
2002c19:dd:dd0:ec00:c25:c25:ddbf:d9c7/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9c7
2012c19:dd:dd0:ec00:c25:c25:ddbf:d9c8/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9c8
2022c19:dd:dd0:ec00:c25:c25:ddbf:d9c9/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9c9
2032c19:dd:dd0:ec00:c25:c25:ddbf:d9ca/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9ca
2042c19:dd:dd0:ec00:c25:c25:ddbf:d9cb/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9cb
2052c19:dd:dd0:ec00:c25:c25:ddbf:d9cc/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9cc
2062c19:dd:dd0:ec00:c25:c25:ddbf:d9cd/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9cd
2072c19:dd:dd0:ec00:c25:c25:ddbf:d9ce/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9ce
2082c19:dd:dd0:ec00:c25:c25:ddbf:d9cf/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9cf
2092c19:dd:dd0:ec00:c25:c25:ddbf:d9d0/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9d0
2102c19:dd:dd0:ec00:c25:c25:ddbf:d9d1/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9d1
2112c19:dd:dd0:ec00:c25:c25:ddbf:d9d2/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9d2
2122c19:dd:dd0:ec00:c25:c25:ddbf:d9d3/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9d3
2132c19:dd:dd0:ec00:c25:c25:ddbf:d9d4/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9d4
2142c19:dd:dd0:ec00:c25:c25:ddbf:d9d5/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9d5
2152c19:dd:dd0:ec00:c25:c25:ddbf:d9d6/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9d6
2162c19:dd:dd0:ec00:c25:c25:ddbf:d9d7/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9d7
2172c19:dd:dd0:ec00:c25:c25:ddbf:d9d8/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9d8
2182c19:dd:dd0:ec00:c25:c25:ddbf:d9d9/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9d9
2192c19:dd:dd0:ec00:c25:c25:ddbf:d9da/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9da
2202c19:dd:dd0:ec00:c25:c25:ddbf:d9db/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9db
2212c19:dd:dd0:ec00:c25:c25:ddbf:d9dc/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9dc
2222c19:dd:dd0:ec00:c25:c25:ddbf:d9dd/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9dd
2232c19:dd:dd0:ec00:c25:c25:ddbf:d9de/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9de
2242c19:dd:dd0:ec00:c25:c25:ddbf:d9df/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9df
2252c19:dd:dd0:ec00:c25:c25:ddbf:d9e0/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9e0
2262c19:dd:dd0:ec00:c25:c25:ddbf:d9e1/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9e1
2272c19:dd:dd0:ec00:c25:c25:ddbf:d9e2/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9e2
2282c19:dd:dd0:ec00:c25:c25:ddbf:d9e3/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9e3
2292c19:dd:dd0:ec00:c25:c25:ddbf:d9e4/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9e4
2302c19:dd:dd0:ec00:c25:c25:ddbf:d9e5/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9e5
2312c19:dd:dd0:ec00:c25:c25:ddbf:d9e6/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9e6
2322c19:dd:dd0:ec00:c25:c25:ddbf:d9e7/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9e7
2332c19:dd:dd0:ec00:c25:c25:ddbf:d9e8/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9e8
2342c19:dd:dd0:ec00:c25:c25:ddbf:d9e9/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9e9
2352c19:dd:dd0:ec00:c25:c25:ddbf:d9ea/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9ea
2362c19:dd:dd0:ec00:c25:c25:ddbf:d9eb/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9eb
2372c19:dd:dd0:ec00:c25:c25:ddbf:d9ec/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9ec
2382c19:dd:dd0:ec00:c25:c25:ddbf:d9ed/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9ed
2392c19:dd:dd0:ec00:c25:c25:ddbf:d9ee/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9ee
2402c19:dd:dd0:ec00:c25:c25:ddbf:d9ef/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9ef
2412c19:dd:dd0:ec00:c25:c25:ddbf:d9f0/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9f0
2422c19:dd:dd0:ec00:c25:c25:ddbf:d9f1/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9f1
2432c19:dd:dd0:ec00:c25:c25:ddbf:d9f2/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9f2
2442c19:dd:dd0:ec00:c25:c25:ddbf:d9f3/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9f3
2452c19:dd:dd0:ec00:c25:c25:ddbf:d9f4/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9f4
2462c19:dd:dd0:ec00:c25:c25:ddbf:d9f5/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9f5
2472c19:dd:dd0:ec00:c25:c25:ddbf:d9f6/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9f6
2482c19:dd:dd0:ec00:c25:c25:ddbf:d9f7/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9f7
2492c19:dd:dd0:ec00:c25:c25:ddbf:d9f8/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9f8
2502c19:dd:dd0:ec00:c25:c25:ddbf:d9f9/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9f9
2512c19:dd:dd0:ec00:c25:c25:ddbf:d9fa/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9fa
2522c19:dd:dd0:ec00:c25:c25:ddbf:d9fb/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9fb
2532c19:dd:dd0:ec00:c25:c25:ddbf:d9fc/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9fc
2542c19:dd:dd0:ec00:c25:c25:ddbf:d9fd/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9fd
2552c19:dd:dd0:ec00:c25:c25:ddbf:d9fe/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9fe
2562c19:dd:dd0:ec00:c25:c25:ddbf:d9ff/1282c19:dd:dd0:ec00:c25:c25:ddbf:d9ff

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.