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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:c25a:d00a:f900/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:f900
Last address
2c19:dd:d9:dd:c25:c25a:d00a:f9ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:f900
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.f.a.0.0.d.a.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:c25a:d00a:f900/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:f900/1282c19:dd:d9:dd:c25:c25a:d00a:f900
22c19:dd:d9:dd:c25:c25a:d00a:f901/1282c19:dd:d9:dd:c25:c25a:d00a:f901
32c19:dd:d9:dd:c25:c25a:d00a:f902/1282c19:dd:d9:dd:c25:c25a:d00a:f902
42c19:dd:d9:dd:c25:c25a:d00a:f903/1282c19:dd:d9:dd:c25:c25a:d00a:f903
52c19:dd:d9:dd:c25:c25a:d00a:f904/1282c19:dd:d9:dd:c25:c25a:d00a:f904
62c19:dd:d9:dd:c25:c25a:d00a:f905/1282c19:dd:d9:dd:c25:c25a:d00a:f905
72c19:dd:d9:dd:c25:c25a:d00a:f906/1282c19:dd:d9:dd:c25:c25a:d00a:f906
82c19:dd:d9:dd:c25:c25a:d00a:f907/1282c19:dd:d9:dd:c25:c25a:d00a:f907
92c19:dd:d9:dd:c25:c25a:d00a:f908/1282c19:dd:d9:dd:c25:c25a:d00a:f908
102c19:dd:d9:dd:c25:c25a:d00a:f909/1282c19:dd:d9:dd:c25:c25a:d00a:f909
112c19:dd:d9:dd:c25:c25a:d00a:f90a/1282c19:dd:d9:dd:c25:c25a:d00a:f90a
122c19:dd:d9:dd:c25:c25a:d00a:f90b/1282c19:dd:d9:dd:c25:c25a:d00a:f90b
132c19:dd:d9:dd:c25:c25a:d00a:f90c/1282c19:dd:d9:dd:c25:c25a:d00a:f90c
142c19:dd:d9:dd:c25:c25a:d00a:f90d/1282c19:dd:d9:dd:c25:c25a:d00a:f90d
152c19:dd:d9:dd:c25:c25a:d00a:f90e/1282c19:dd:d9:dd:c25:c25a:d00a:f90e
162c19:dd:d9:dd:c25:c25a:d00a:f90f/1282c19:dd:d9:dd:c25:c25a:d00a:f90f
172c19:dd:d9:dd:c25:c25a:d00a:f910/1282c19:dd:d9:dd:c25:c25a:d00a:f910
182c19:dd:d9:dd:c25:c25a:d00a:f911/1282c19:dd:d9:dd:c25:c25a:d00a:f911
192c19:dd:d9:dd:c25:c25a:d00a:f912/1282c19:dd:d9:dd:c25:c25a:d00a:f912
202c19:dd:d9:dd:c25:c25a:d00a:f913/1282c19:dd:d9:dd:c25:c25a:d00a:f913
212c19:dd:d9:dd:c25:c25a:d00a:f914/1282c19:dd:d9:dd:c25:c25a:d00a:f914
222c19:dd:d9:dd:c25:c25a:d00a:f915/1282c19:dd:d9:dd:c25:c25a:d00a:f915
232c19:dd:d9:dd:c25:c25a:d00a:f916/1282c19:dd:d9:dd:c25:c25a:d00a:f916
242c19:dd:d9:dd:c25:c25a:d00a:f917/1282c19:dd:d9:dd:c25:c25a:d00a:f917
252c19:dd:d9:dd:c25:c25a:d00a:f918/1282c19:dd:d9:dd:c25:c25a:d00a:f918
262c19:dd:d9:dd:c25:c25a:d00a:f919/1282c19:dd:d9:dd:c25:c25a:d00a:f919
272c19:dd:d9:dd:c25:c25a:d00a:f91a/1282c19:dd:d9:dd:c25:c25a:d00a:f91a
282c19:dd:d9:dd:c25:c25a:d00a:f91b/1282c19:dd:d9:dd:c25:c25a:d00a:f91b
292c19:dd:d9:dd:c25:c25a:d00a:f91c/1282c19:dd:d9:dd:c25:c25a:d00a:f91c
302c19:dd:d9:dd:c25:c25a:d00a:f91d/1282c19:dd:d9:dd:c25:c25a:d00a:f91d
312c19:dd:d9:dd:c25:c25a:d00a:f91e/1282c19:dd:d9:dd:c25:c25a:d00a:f91e
322c19:dd:d9:dd:c25:c25a:d00a:f91f/1282c19:dd:d9:dd:c25:c25a:d00a:f91f
332c19:dd:d9:dd:c25:c25a:d00a:f920/1282c19:dd:d9:dd:c25:c25a:d00a:f920
342c19:dd:d9:dd:c25:c25a:d00a:f921/1282c19:dd:d9:dd:c25:c25a:d00a:f921
352c19:dd:d9:dd:c25:c25a:d00a:f922/1282c19:dd:d9:dd:c25:c25a:d00a:f922
362c19:dd:d9:dd:c25:c25a:d00a:f923/1282c19:dd:d9:dd:c25:c25a:d00a:f923
372c19:dd:d9:dd:c25:c25a:d00a:f924/1282c19:dd:d9:dd:c25:c25a:d00a:f924
382c19:dd:d9:dd:c25:c25a:d00a:f925/1282c19:dd:d9:dd:c25:c25a:d00a:f925
392c19:dd:d9:dd:c25:c25a:d00a:f926/1282c19:dd:d9:dd:c25:c25a:d00a:f926
402c19:dd:d9:dd:c25:c25a:d00a:f927/1282c19:dd:d9:dd:c25:c25a:d00a:f927
412c19:dd:d9:dd:c25:c25a:d00a:f928/1282c19:dd:d9:dd:c25:c25a:d00a:f928
422c19:dd:d9:dd:c25:c25a:d00a:f929/1282c19:dd:d9:dd:c25:c25a:d00a:f929
432c19:dd:d9:dd:c25:c25a:d00a:f92a/1282c19:dd:d9:dd:c25:c25a:d00a:f92a
442c19:dd:d9:dd:c25:c25a:d00a:f92b/1282c19:dd:d9:dd:c25:c25a:d00a:f92b
452c19:dd:d9:dd:c25:c25a:d00a:f92c/1282c19:dd:d9:dd:c25:c25a:d00a:f92c
462c19:dd:d9:dd:c25:c25a:d00a:f92d/1282c19:dd:d9:dd:c25:c25a:d00a:f92d
472c19:dd:d9:dd:c25:c25a:d00a:f92e/1282c19:dd:d9:dd:c25:c25a:d00a:f92e
482c19:dd:d9:dd:c25:c25a:d00a:f92f/1282c19:dd:d9:dd:c25:c25a:d00a:f92f
492c19:dd:d9:dd:c25:c25a:d00a:f930/1282c19:dd:d9:dd:c25:c25a:d00a:f930
502c19:dd:d9:dd:c25:c25a:d00a:f931/1282c19:dd:d9:dd:c25:c25a:d00a:f931
512c19:dd:d9:dd:c25:c25a:d00a:f932/1282c19:dd:d9:dd:c25:c25a:d00a:f932
522c19:dd:d9:dd:c25:c25a:d00a:f933/1282c19:dd:d9:dd:c25:c25a:d00a:f933
532c19:dd:d9:dd:c25:c25a:d00a:f934/1282c19:dd:d9:dd:c25:c25a:d00a:f934
542c19:dd:d9:dd:c25:c25a:d00a:f935/1282c19:dd:d9:dd:c25:c25a:d00a:f935
552c19:dd:d9:dd:c25:c25a:d00a:f936/1282c19:dd:d9:dd:c25:c25a:d00a:f936
562c19:dd:d9:dd:c25:c25a:d00a:f937/1282c19:dd:d9:dd:c25:c25a:d00a:f937
572c19:dd:d9:dd:c25:c25a:d00a:f938/1282c19:dd:d9:dd:c25:c25a:d00a:f938
582c19:dd:d9:dd:c25:c25a:d00a:f939/1282c19:dd:d9:dd:c25:c25a:d00a:f939
592c19:dd:d9:dd:c25:c25a:d00a:f93a/1282c19:dd:d9:dd:c25:c25a:d00a:f93a
602c19:dd:d9:dd:c25:c25a:d00a:f93b/1282c19:dd:d9:dd:c25:c25a:d00a:f93b
612c19:dd:d9:dd:c25:c25a:d00a:f93c/1282c19:dd:d9:dd:c25:c25a:d00a:f93c
622c19:dd:d9:dd:c25:c25a:d00a:f93d/1282c19:dd:d9:dd:c25:c25a:d00a:f93d
632c19:dd:d9:dd:c25:c25a:d00a:f93e/1282c19:dd:d9:dd:c25:c25a:d00a:f93e
642c19:dd:d9:dd:c25:c25a:d00a:f93f/1282c19:dd:d9:dd:c25:c25a:d00a:f93f
652c19:dd:d9:dd:c25:c25a:d00a:f940/1282c19:dd:d9:dd:c25:c25a:d00a:f940
662c19:dd:d9:dd:c25:c25a:d00a:f941/1282c19:dd:d9:dd:c25:c25a:d00a:f941
672c19:dd:d9:dd:c25:c25a:d00a:f942/1282c19:dd:d9:dd:c25:c25a:d00a:f942
682c19:dd:d9:dd:c25:c25a:d00a:f943/1282c19:dd:d9:dd:c25:c25a:d00a:f943
692c19:dd:d9:dd:c25:c25a:d00a:f944/1282c19:dd:d9:dd:c25:c25a:d00a:f944
702c19:dd:d9:dd:c25:c25a:d00a:f945/1282c19:dd:d9:dd:c25:c25a:d00a:f945
712c19:dd:d9:dd:c25:c25a:d00a:f946/1282c19:dd:d9:dd:c25:c25a:d00a:f946
722c19:dd:d9:dd:c25:c25a:d00a:f947/1282c19:dd:d9:dd:c25:c25a:d00a:f947
732c19:dd:d9:dd:c25:c25a:d00a:f948/1282c19:dd:d9:dd:c25:c25a:d00a:f948
742c19:dd:d9:dd:c25:c25a:d00a:f949/1282c19:dd:d9:dd:c25:c25a:d00a:f949
752c19:dd:d9:dd:c25:c25a:d00a:f94a/1282c19:dd:d9:dd:c25:c25a:d00a:f94a
762c19:dd:d9:dd:c25:c25a:d00a:f94b/1282c19:dd:d9:dd:c25:c25a:d00a:f94b
772c19:dd:d9:dd:c25:c25a:d00a:f94c/1282c19:dd:d9:dd:c25:c25a:d00a:f94c
782c19:dd:d9:dd:c25:c25a:d00a:f94d/1282c19:dd:d9:dd:c25:c25a:d00a:f94d
792c19:dd:d9:dd:c25:c25a:d00a:f94e/1282c19:dd:d9:dd:c25:c25a:d00a:f94e
802c19:dd:d9:dd:c25:c25a:d00a:f94f/1282c19:dd:d9:dd:c25:c25a:d00a:f94f
812c19:dd:d9:dd:c25:c25a:d00a:f950/1282c19:dd:d9:dd:c25:c25a:d00a:f950
822c19:dd:d9:dd:c25:c25a:d00a:f951/1282c19:dd:d9:dd:c25:c25a:d00a:f951
832c19:dd:d9:dd:c25:c25a:d00a:f952/1282c19:dd:d9:dd:c25:c25a:d00a:f952
842c19:dd:d9:dd:c25:c25a:d00a:f953/1282c19:dd:d9:dd:c25:c25a:d00a:f953
852c19:dd:d9:dd:c25:c25a:d00a:f954/1282c19:dd:d9:dd:c25:c25a:d00a:f954
862c19:dd:d9:dd:c25:c25a:d00a:f955/1282c19:dd:d9:dd:c25:c25a:d00a:f955
872c19:dd:d9:dd:c25:c25a:d00a:f956/1282c19:dd:d9:dd:c25:c25a:d00a:f956
882c19:dd:d9:dd:c25:c25a:d00a:f957/1282c19:dd:d9:dd:c25:c25a:d00a:f957
892c19:dd:d9:dd:c25:c25a:d00a:f958/1282c19:dd:d9:dd:c25:c25a:d00a:f958
902c19:dd:d9:dd:c25:c25a:d00a:f959/1282c19:dd:d9:dd:c25:c25a:d00a:f959
912c19:dd:d9:dd:c25:c25a:d00a:f95a/1282c19:dd:d9:dd:c25:c25a:d00a:f95a
922c19:dd:d9:dd:c25:c25a:d00a:f95b/1282c19:dd:d9:dd:c25:c25a:d00a:f95b
932c19:dd:d9:dd:c25:c25a:d00a:f95c/1282c19:dd:d9:dd:c25:c25a:d00a:f95c
942c19:dd:d9:dd:c25:c25a:d00a:f95d/1282c19:dd:d9:dd:c25:c25a:d00a:f95d
952c19:dd:d9:dd:c25:c25a:d00a:f95e/1282c19:dd:d9:dd:c25:c25a:d00a:f95e
962c19:dd:d9:dd:c25:c25a:d00a:f95f/1282c19:dd:d9:dd:c25:c25a:d00a:f95f
972c19:dd:d9:dd:c25:c25a:d00a:f960/1282c19:dd:d9:dd:c25:c25a:d00a:f960
982c19:dd:d9:dd:c25:c25a:d00a:f961/1282c19:dd:d9:dd:c25:c25a:d00a:f961
992c19:dd:d9:dd:c25:c25a:d00a:f962/1282c19:dd:d9:dd:c25:c25a:d00a:f962
1002c19:dd:d9:dd:c25:c25a:d00a:f963/1282c19:dd:d9:dd:c25:c25a:d00a:f963
1012c19:dd:d9:dd:c25:c25a:d00a:f964/1282c19:dd:d9:dd:c25:c25a:d00a:f964
1022c19:dd:d9:dd:c25:c25a:d00a:f965/1282c19:dd:d9:dd:c25:c25a:d00a:f965
1032c19:dd:d9:dd:c25:c25a:d00a:f966/1282c19:dd:d9:dd:c25:c25a:d00a:f966
1042c19:dd:d9:dd:c25:c25a:d00a:f967/1282c19:dd:d9:dd:c25:c25a:d00a:f967
1052c19:dd:d9:dd:c25:c25a:d00a:f968/1282c19:dd:d9:dd:c25:c25a:d00a:f968
1062c19:dd:d9:dd:c25:c25a:d00a:f969/1282c19:dd:d9:dd:c25:c25a:d00a:f969
1072c19:dd:d9:dd:c25:c25a:d00a:f96a/1282c19:dd:d9:dd:c25:c25a:d00a:f96a
1082c19:dd:d9:dd:c25:c25a:d00a:f96b/1282c19:dd:d9:dd:c25:c25a:d00a:f96b
1092c19:dd:d9:dd:c25:c25a:d00a:f96c/1282c19:dd:d9:dd:c25:c25a:d00a:f96c
1102c19:dd:d9:dd:c25:c25a:d00a:f96d/1282c19:dd:d9:dd:c25:c25a:d00a:f96d
1112c19:dd:d9:dd:c25:c25a:d00a:f96e/1282c19:dd:d9:dd:c25:c25a:d00a:f96e
1122c19:dd:d9:dd:c25:c25a:d00a:f96f/1282c19:dd:d9:dd:c25:c25a:d00a:f96f
1132c19:dd:d9:dd:c25:c25a:d00a:f970/1282c19:dd:d9:dd:c25:c25a:d00a:f970
1142c19:dd:d9:dd:c25:c25a:d00a:f971/1282c19:dd:d9:dd:c25:c25a:d00a:f971
1152c19:dd:d9:dd:c25:c25a:d00a:f972/1282c19:dd:d9:dd:c25:c25a:d00a:f972
1162c19:dd:d9:dd:c25:c25a:d00a:f973/1282c19:dd:d9:dd:c25:c25a:d00a:f973
1172c19:dd:d9:dd:c25:c25a:d00a:f974/1282c19:dd:d9:dd:c25:c25a:d00a:f974
1182c19:dd:d9:dd:c25:c25a:d00a:f975/1282c19:dd:d9:dd:c25:c25a:d00a:f975
1192c19:dd:d9:dd:c25:c25a:d00a:f976/1282c19:dd:d9:dd:c25:c25a:d00a:f976
1202c19:dd:d9:dd:c25:c25a:d00a:f977/1282c19:dd:d9:dd:c25:c25a:d00a:f977
1212c19:dd:d9:dd:c25:c25a:d00a:f978/1282c19:dd:d9:dd:c25:c25a:d00a:f978
1222c19:dd:d9:dd:c25:c25a:d00a:f979/1282c19:dd:d9:dd:c25:c25a:d00a:f979
1232c19:dd:d9:dd:c25:c25a:d00a:f97a/1282c19:dd:d9:dd:c25:c25a:d00a:f97a
1242c19:dd:d9:dd:c25:c25a:d00a:f97b/1282c19:dd:d9:dd:c25:c25a:d00a:f97b
1252c19:dd:d9:dd:c25:c25a:d00a:f97c/1282c19:dd:d9:dd:c25:c25a:d00a:f97c
1262c19:dd:d9:dd:c25:c25a:d00a:f97d/1282c19:dd:d9:dd:c25:c25a:d00a:f97d
1272c19:dd:d9:dd:c25:c25a:d00a:f97e/1282c19:dd:d9:dd:c25:c25a:d00a:f97e
1282c19:dd:d9:dd:c25:c25a:d00a:f97f/1282c19:dd:d9:dd:c25:c25a:d00a:f97f
1292c19:dd:d9:dd:c25:c25a:d00a:f980/1282c19:dd:d9:dd:c25:c25a:d00a:f980
1302c19:dd:d9:dd:c25:c25a:d00a:f981/1282c19:dd:d9:dd:c25:c25a:d00a:f981
1312c19:dd:d9:dd:c25:c25a:d00a:f982/1282c19:dd:d9:dd:c25:c25a:d00a:f982
1322c19:dd:d9:dd:c25:c25a:d00a:f983/1282c19:dd:d9:dd:c25:c25a:d00a:f983
1332c19:dd:d9:dd:c25:c25a:d00a:f984/1282c19:dd:d9:dd:c25:c25a:d00a:f984
1342c19:dd:d9:dd:c25:c25a:d00a:f985/1282c19:dd:d9:dd:c25:c25a:d00a:f985
1352c19:dd:d9:dd:c25:c25a:d00a:f986/1282c19:dd:d9:dd:c25:c25a:d00a:f986
1362c19:dd:d9:dd:c25:c25a:d00a:f987/1282c19:dd:d9:dd:c25:c25a:d00a:f987
1372c19:dd:d9:dd:c25:c25a:d00a:f988/1282c19:dd:d9:dd:c25:c25a:d00a:f988
1382c19:dd:d9:dd:c25:c25a:d00a:f989/1282c19:dd:d9:dd:c25:c25a:d00a:f989
1392c19:dd:d9:dd:c25:c25a:d00a:f98a/1282c19:dd:d9:dd:c25:c25a:d00a:f98a
1402c19:dd:d9:dd:c25:c25a:d00a:f98b/1282c19:dd:d9:dd:c25:c25a:d00a:f98b
1412c19:dd:d9:dd:c25:c25a:d00a:f98c/1282c19:dd:d9:dd:c25:c25a:d00a:f98c
1422c19:dd:d9:dd:c25:c25a:d00a:f98d/1282c19:dd:d9:dd:c25:c25a:d00a:f98d
1432c19:dd:d9:dd:c25:c25a:d00a:f98e/1282c19:dd:d9:dd:c25:c25a:d00a:f98e
1442c19:dd:d9:dd:c25:c25a:d00a:f98f/1282c19:dd:d9:dd:c25:c25a:d00a:f98f
1452c19:dd:d9:dd:c25:c25a:d00a:f990/1282c19:dd:d9:dd:c25:c25a:d00a:f990
1462c19:dd:d9:dd:c25:c25a:d00a:f991/1282c19:dd:d9:dd:c25:c25a:d00a:f991
1472c19:dd:d9:dd:c25:c25a:d00a:f992/1282c19:dd:d9:dd:c25:c25a:d00a:f992
1482c19:dd:d9:dd:c25:c25a:d00a:f993/1282c19:dd:d9:dd:c25:c25a:d00a:f993
1492c19:dd:d9:dd:c25:c25a:d00a:f994/1282c19:dd:d9:dd:c25:c25a:d00a:f994
1502c19:dd:d9:dd:c25:c25a:d00a:f995/1282c19:dd:d9:dd:c25:c25a:d00a:f995
1512c19:dd:d9:dd:c25:c25a:d00a:f996/1282c19:dd:d9:dd:c25:c25a:d00a:f996
1522c19:dd:d9:dd:c25:c25a:d00a:f997/1282c19:dd:d9:dd:c25:c25a:d00a:f997
1532c19:dd:d9:dd:c25:c25a:d00a:f998/1282c19:dd:d9:dd:c25:c25a:d00a:f998
1542c19:dd:d9:dd:c25:c25a:d00a:f999/1282c19:dd:d9:dd:c25:c25a:d00a:f999
1552c19:dd:d9:dd:c25:c25a:d00a:f99a/1282c19:dd:d9:dd:c25:c25a:d00a:f99a
1562c19:dd:d9:dd:c25:c25a:d00a:f99b/1282c19:dd:d9:dd:c25:c25a:d00a:f99b
1572c19:dd:d9:dd:c25:c25a:d00a:f99c/1282c19:dd:d9:dd:c25:c25a:d00a:f99c
1582c19:dd:d9:dd:c25:c25a:d00a:f99d/1282c19:dd:d9:dd:c25:c25a:d00a:f99d
1592c19:dd:d9:dd:c25:c25a:d00a:f99e/1282c19:dd:d9:dd:c25:c25a:d00a:f99e
1602c19:dd:d9:dd:c25:c25a:d00a:f99f/1282c19:dd:d9:dd:c25:c25a:d00a:f99f
1612c19:dd:d9:dd:c25:c25a:d00a:f9a0/1282c19:dd:d9:dd:c25:c25a:d00a:f9a0
1622c19:dd:d9:dd:c25:c25a:d00a:f9a1/1282c19:dd:d9:dd:c25:c25a:d00a:f9a1
1632c19:dd:d9:dd:c25:c25a:d00a:f9a2/1282c19:dd:d9:dd:c25:c25a:d00a:f9a2
1642c19:dd:d9:dd:c25:c25a:d00a:f9a3/1282c19:dd:d9:dd:c25:c25a:d00a:f9a3
1652c19:dd:d9:dd:c25:c25a:d00a:f9a4/1282c19:dd:d9:dd:c25:c25a:d00a:f9a4
1662c19:dd:d9:dd:c25:c25a:d00a:f9a5/1282c19:dd:d9:dd:c25:c25a:d00a:f9a5
1672c19:dd:d9:dd:c25:c25a:d00a:f9a6/1282c19:dd:d9:dd:c25:c25a:d00a:f9a6
1682c19:dd:d9:dd:c25:c25a:d00a:f9a7/1282c19:dd:d9:dd:c25:c25a:d00a:f9a7
1692c19:dd:d9:dd:c25:c25a:d00a:f9a8/1282c19:dd:d9:dd:c25:c25a:d00a:f9a8
1702c19:dd:d9:dd:c25:c25a:d00a:f9a9/1282c19:dd:d9:dd:c25:c25a:d00a:f9a9
1712c19:dd:d9:dd:c25:c25a:d00a:f9aa/1282c19:dd:d9:dd:c25:c25a:d00a:f9aa
1722c19:dd:d9:dd:c25:c25a:d00a:f9ab/1282c19:dd:d9:dd:c25:c25a:d00a:f9ab
1732c19:dd:d9:dd:c25:c25a:d00a:f9ac/1282c19:dd:d9:dd:c25:c25a:d00a:f9ac
1742c19:dd:d9:dd:c25:c25a:d00a:f9ad/1282c19:dd:d9:dd:c25:c25a:d00a:f9ad
1752c19:dd:d9:dd:c25:c25a:d00a:f9ae/1282c19:dd:d9:dd:c25:c25a:d00a:f9ae
1762c19:dd:d9:dd:c25:c25a:d00a:f9af/1282c19:dd:d9:dd:c25:c25a:d00a:f9af
1772c19:dd:d9:dd:c25:c25a:d00a:f9b0/1282c19:dd:d9:dd:c25:c25a:d00a:f9b0
1782c19:dd:d9:dd:c25:c25a:d00a:f9b1/1282c19:dd:d9:dd:c25:c25a:d00a:f9b1
1792c19:dd:d9:dd:c25:c25a:d00a:f9b2/1282c19:dd:d9:dd:c25:c25a:d00a:f9b2
1802c19:dd:d9:dd:c25:c25a:d00a:f9b3/1282c19:dd:d9:dd:c25:c25a:d00a:f9b3
1812c19:dd:d9:dd:c25:c25a:d00a:f9b4/1282c19:dd:d9:dd:c25:c25a:d00a:f9b4
1822c19:dd:d9:dd:c25:c25a:d00a:f9b5/1282c19:dd:d9:dd:c25:c25a:d00a:f9b5
1832c19:dd:d9:dd:c25:c25a:d00a:f9b6/1282c19:dd:d9:dd:c25:c25a:d00a:f9b6
1842c19:dd:d9:dd:c25:c25a:d00a:f9b7/1282c19:dd:d9:dd:c25:c25a:d00a:f9b7
1852c19:dd:d9:dd:c25:c25a:d00a:f9b8/1282c19:dd:d9:dd:c25:c25a:d00a:f9b8
1862c19:dd:d9:dd:c25:c25a:d00a:f9b9/1282c19:dd:d9:dd:c25:c25a:d00a:f9b9
1872c19:dd:d9:dd:c25:c25a:d00a:f9ba/1282c19:dd:d9:dd:c25:c25a:d00a:f9ba
1882c19:dd:d9:dd:c25:c25a:d00a:f9bb/1282c19:dd:d9:dd:c25:c25a:d00a:f9bb
1892c19:dd:d9:dd:c25:c25a:d00a:f9bc/1282c19:dd:d9:dd:c25:c25a:d00a:f9bc
1902c19:dd:d9:dd:c25:c25a:d00a:f9bd/1282c19:dd:d9:dd:c25:c25a:d00a:f9bd
1912c19:dd:d9:dd:c25:c25a:d00a:f9be/1282c19:dd:d9:dd:c25:c25a:d00a:f9be
1922c19:dd:d9:dd:c25:c25a:d00a:f9bf/1282c19:dd:d9:dd:c25:c25a:d00a:f9bf
1932c19:dd:d9:dd:c25:c25a:d00a:f9c0/1282c19:dd:d9:dd:c25:c25a:d00a:f9c0
1942c19:dd:d9:dd:c25:c25a:d00a:f9c1/1282c19:dd:d9:dd:c25:c25a:d00a:f9c1
1952c19:dd:d9:dd:c25:c25a:d00a:f9c2/1282c19:dd:d9:dd:c25:c25a:d00a:f9c2
1962c19:dd:d9:dd:c25:c25a:d00a:f9c3/1282c19:dd:d9:dd:c25:c25a:d00a:f9c3
1972c19:dd:d9:dd:c25:c25a:d00a:f9c4/1282c19:dd:d9:dd:c25:c25a:d00a:f9c4
1982c19:dd:d9:dd:c25:c25a:d00a:f9c5/1282c19:dd:d9:dd:c25:c25a:d00a:f9c5
1992c19:dd:d9:dd:c25:c25a:d00a:f9c6/1282c19:dd:d9:dd:c25:c25a:d00a:f9c6
2002c19:dd:d9:dd:c25:c25a:d00a:f9c7/1282c19:dd:d9:dd:c25:c25a:d00a:f9c7
2012c19:dd:d9:dd:c25:c25a:d00a:f9c8/1282c19:dd:d9:dd:c25:c25a:d00a:f9c8
2022c19:dd:d9:dd:c25:c25a:d00a:f9c9/1282c19:dd:d9:dd:c25:c25a:d00a:f9c9
2032c19:dd:d9:dd:c25:c25a:d00a:f9ca/1282c19:dd:d9:dd:c25:c25a:d00a:f9ca
2042c19:dd:d9:dd:c25:c25a:d00a:f9cb/1282c19:dd:d9:dd:c25:c25a:d00a:f9cb
2052c19:dd:d9:dd:c25:c25a:d00a:f9cc/1282c19:dd:d9:dd:c25:c25a:d00a:f9cc
2062c19:dd:d9:dd:c25:c25a:d00a:f9cd/1282c19:dd:d9:dd:c25:c25a:d00a:f9cd
2072c19:dd:d9:dd:c25:c25a:d00a:f9ce/1282c19:dd:d9:dd:c25:c25a:d00a:f9ce
2082c19:dd:d9:dd:c25:c25a:d00a:f9cf/1282c19:dd:d9:dd:c25:c25a:d00a:f9cf
2092c19:dd:d9:dd:c25:c25a:d00a:f9d0/1282c19:dd:d9:dd:c25:c25a:d00a:f9d0
2102c19:dd:d9:dd:c25:c25a:d00a:f9d1/1282c19:dd:d9:dd:c25:c25a:d00a:f9d1
2112c19:dd:d9:dd:c25:c25a:d00a:f9d2/1282c19:dd:d9:dd:c25:c25a:d00a:f9d2
2122c19:dd:d9:dd:c25:c25a:d00a:f9d3/1282c19:dd:d9:dd:c25:c25a:d00a:f9d3
2132c19:dd:d9:dd:c25:c25a:d00a:f9d4/1282c19:dd:d9:dd:c25:c25a:d00a:f9d4
2142c19:dd:d9:dd:c25:c25a:d00a:f9d5/1282c19:dd:d9:dd:c25:c25a:d00a:f9d5
2152c19:dd:d9:dd:c25:c25a:d00a:f9d6/1282c19:dd:d9:dd:c25:c25a:d00a:f9d6
2162c19:dd:d9:dd:c25:c25a:d00a:f9d7/1282c19:dd:d9:dd:c25:c25a:d00a:f9d7
2172c19:dd:d9:dd:c25:c25a:d00a:f9d8/1282c19:dd:d9:dd:c25:c25a:d00a:f9d8
2182c19:dd:d9:dd:c25:c25a:d00a:f9d9/1282c19:dd:d9:dd:c25:c25a:d00a:f9d9
2192c19:dd:d9:dd:c25:c25a:d00a:f9da/1282c19:dd:d9:dd:c25:c25a:d00a:f9da
2202c19:dd:d9:dd:c25:c25a:d00a:f9db/1282c19:dd:d9:dd:c25:c25a:d00a:f9db
2212c19:dd:d9:dd:c25:c25a:d00a:f9dc/1282c19:dd:d9:dd:c25:c25a:d00a:f9dc
2222c19:dd:d9:dd:c25:c25a:d00a:f9dd/1282c19:dd:d9:dd:c25:c25a:d00a:f9dd
2232c19:dd:d9:dd:c25:c25a:d00a:f9de/1282c19:dd:d9:dd:c25:c25a:d00a:f9de
2242c19:dd:d9:dd:c25:c25a:d00a:f9df/1282c19:dd:d9:dd:c25:c25a:d00a:f9df
2252c19:dd:d9:dd:c25:c25a:d00a:f9e0/1282c19:dd:d9:dd:c25:c25a:d00a:f9e0
2262c19:dd:d9:dd:c25:c25a:d00a:f9e1/1282c19:dd:d9:dd:c25:c25a:d00a:f9e1
2272c19:dd:d9:dd:c25:c25a:d00a:f9e2/1282c19:dd:d9:dd:c25:c25a:d00a:f9e2
2282c19:dd:d9:dd:c25:c25a:d00a:f9e3/1282c19:dd:d9:dd:c25:c25a:d00a:f9e3
2292c19:dd:d9:dd:c25:c25a:d00a:f9e4/1282c19:dd:d9:dd:c25:c25a:d00a:f9e4
2302c19:dd:d9:dd:c25:c25a:d00a:f9e5/1282c19:dd:d9:dd:c25:c25a:d00a:f9e5
2312c19:dd:d9:dd:c25:c25a:d00a:f9e6/1282c19:dd:d9:dd:c25:c25a:d00a:f9e6
2322c19:dd:d9:dd:c25:c25a:d00a:f9e7/1282c19:dd:d9:dd:c25:c25a:d00a:f9e7
2332c19:dd:d9:dd:c25:c25a:d00a:f9e8/1282c19:dd:d9:dd:c25:c25a:d00a:f9e8
2342c19:dd:d9:dd:c25:c25a:d00a:f9e9/1282c19:dd:d9:dd:c25:c25a:d00a:f9e9
2352c19:dd:d9:dd:c25:c25a:d00a:f9ea/1282c19:dd:d9:dd:c25:c25a:d00a:f9ea
2362c19:dd:d9:dd:c25:c25a:d00a:f9eb/1282c19:dd:d9:dd:c25:c25a:d00a:f9eb
2372c19:dd:d9:dd:c25:c25a:d00a:f9ec/1282c19:dd:d9:dd:c25:c25a:d00a:f9ec
2382c19:dd:d9:dd:c25:c25a:d00a:f9ed/1282c19:dd:d9:dd:c25:c25a:d00a:f9ed
2392c19:dd:d9:dd:c25:c25a:d00a:f9ee/1282c19:dd:d9:dd:c25:c25a:d00a:f9ee
2402c19:dd:d9:dd:c25:c25a:d00a:f9ef/1282c19:dd:d9:dd:c25:c25a:d00a:f9ef
2412c19:dd:d9:dd:c25:c25a:d00a:f9f0/1282c19:dd:d9:dd:c25:c25a:d00a:f9f0
2422c19:dd:d9:dd:c25:c25a:d00a:f9f1/1282c19:dd:d9:dd:c25:c25a:d00a:f9f1
2432c19:dd:d9:dd:c25:c25a:d00a:f9f2/1282c19:dd:d9:dd:c25:c25a:d00a:f9f2
2442c19:dd:d9:dd:c25:c25a:d00a:f9f3/1282c19:dd:d9:dd:c25:c25a:d00a:f9f3
2452c19:dd:d9:dd:c25:c25a:d00a:f9f4/1282c19:dd:d9:dd:c25:c25a:d00a:f9f4
2462c19:dd:d9:dd:c25:c25a:d00a:f9f5/1282c19:dd:d9:dd:c25:c25a:d00a:f9f5
2472c19:dd:d9:dd:c25:c25a:d00a:f9f6/1282c19:dd:d9:dd:c25:c25a:d00a:f9f6
2482c19:dd:d9:dd:c25:c25a:d00a:f9f7/1282c19:dd:d9:dd:c25:c25a:d00a:f9f7
2492c19:dd:d9:dd:c25:c25a:d00a:f9f8/1282c19:dd:d9:dd:c25:c25a:d00a:f9f8
2502c19:dd:d9:dd:c25:c25a:d00a:f9f9/1282c19:dd:d9:dd:c25:c25a:d00a:f9f9
2512c19:dd:d9:dd:c25:c25a:d00a:f9fa/1282c19:dd:d9:dd:c25:c25a:d00a:f9fa
2522c19:dd:d9:dd:c25:c25a:d00a:f9fb/1282c19:dd:d9:dd:c25:c25a:d00a:f9fb
2532c19:dd:d9:dd:c25:c25a:d00a:f9fc/1282c19:dd:d9:dd:c25:c25a:d00a:f9fc
2542c19:dd:d9:dd:c25:c25a:d00a:f9fd/1282c19:dd:d9:dd:c25:c25a:d00a:f9fd
2552c19:dd:d9:dd:c25:c25a:d00a:f9fe/1282c19:dd:d9:dd:c25:c25a:d00a:f9fe
2562c19:dd:d9:dd:c25:c25a:d00a:f9ff/1282c19:dd:d9:dd:c25:c25a:d00a:f9ff

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.