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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:e900/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:e900
Last address
2c19:dd:d9:dd:c25:c25a:d00a:e9ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:e900
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.e.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:e900/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:e900/1282c19:dd:d9:dd:c25:c25a:d00a:e900
22c19:dd:d9:dd:c25:c25a:d00a:e901/1282c19:dd:d9:dd:c25:c25a:d00a:e901
32c19:dd:d9:dd:c25:c25a:d00a:e902/1282c19:dd:d9:dd:c25:c25a:d00a:e902
42c19:dd:d9:dd:c25:c25a:d00a:e903/1282c19:dd:d9:dd:c25:c25a:d00a:e903
52c19:dd:d9:dd:c25:c25a:d00a:e904/1282c19:dd:d9:dd:c25:c25a:d00a:e904
62c19:dd:d9:dd:c25:c25a:d00a:e905/1282c19:dd:d9:dd:c25:c25a:d00a:e905
72c19:dd:d9:dd:c25:c25a:d00a:e906/1282c19:dd:d9:dd:c25:c25a:d00a:e906
82c19:dd:d9:dd:c25:c25a:d00a:e907/1282c19:dd:d9:dd:c25:c25a:d00a:e907
92c19:dd:d9:dd:c25:c25a:d00a:e908/1282c19:dd:d9:dd:c25:c25a:d00a:e908
102c19:dd:d9:dd:c25:c25a:d00a:e909/1282c19:dd:d9:dd:c25:c25a:d00a:e909
112c19:dd:d9:dd:c25:c25a:d00a:e90a/1282c19:dd:d9:dd:c25:c25a:d00a:e90a
122c19:dd:d9:dd:c25:c25a:d00a:e90b/1282c19:dd:d9:dd:c25:c25a:d00a:e90b
132c19:dd:d9:dd:c25:c25a:d00a:e90c/1282c19:dd:d9:dd:c25:c25a:d00a:e90c
142c19:dd:d9:dd:c25:c25a:d00a:e90d/1282c19:dd:d9:dd:c25:c25a:d00a:e90d
152c19:dd:d9:dd:c25:c25a:d00a:e90e/1282c19:dd:d9:dd:c25:c25a:d00a:e90e
162c19:dd:d9:dd:c25:c25a:d00a:e90f/1282c19:dd:d9:dd:c25:c25a:d00a:e90f
172c19:dd:d9:dd:c25:c25a:d00a:e910/1282c19:dd:d9:dd:c25:c25a:d00a:e910
182c19:dd:d9:dd:c25:c25a:d00a:e911/1282c19:dd:d9:dd:c25:c25a:d00a:e911
192c19:dd:d9:dd:c25:c25a:d00a:e912/1282c19:dd:d9:dd:c25:c25a:d00a:e912
202c19:dd:d9:dd:c25:c25a:d00a:e913/1282c19:dd:d9:dd:c25:c25a:d00a:e913
212c19:dd:d9:dd:c25:c25a:d00a:e914/1282c19:dd:d9:dd:c25:c25a:d00a:e914
222c19:dd:d9:dd:c25:c25a:d00a:e915/1282c19:dd:d9:dd:c25:c25a:d00a:e915
232c19:dd:d9:dd:c25:c25a:d00a:e916/1282c19:dd:d9:dd:c25:c25a:d00a:e916
242c19:dd:d9:dd:c25:c25a:d00a:e917/1282c19:dd:d9:dd:c25:c25a:d00a:e917
252c19:dd:d9:dd:c25:c25a:d00a:e918/1282c19:dd:d9:dd:c25:c25a:d00a:e918
262c19:dd:d9:dd:c25:c25a:d00a:e919/1282c19:dd:d9:dd:c25:c25a:d00a:e919
272c19:dd:d9:dd:c25:c25a:d00a:e91a/1282c19:dd:d9:dd:c25:c25a:d00a:e91a
282c19:dd:d9:dd:c25:c25a:d00a:e91b/1282c19:dd:d9:dd:c25:c25a:d00a:e91b
292c19:dd:d9:dd:c25:c25a:d00a:e91c/1282c19:dd:d9:dd:c25:c25a:d00a:e91c
302c19:dd:d9:dd:c25:c25a:d00a:e91d/1282c19:dd:d9:dd:c25:c25a:d00a:e91d
312c19:dd:d9:dd:c25:c25a:d00a:e91e/1282c19:dd:d9:dd:c25:c25a:d00a:e91e
322c19:dd:d9:dd:c25:c25a:d00a:e91f/1282c19:dd:d9:dd:c25:c25a:d00a:e91f
332c19:dd:d9:dd:c25:c25a:d00a:e920/1282c19:dd:d9:dd:c25:c25a:d00a:e920
342c19:dd:d9:dd:c25:c25a:d00a:e921/1282c19:dd:d9:dd:c25:c25a:d00a:e921
352c19:dd:d9:dd:c25:c25a:d00a:e922/1282c19:dd:d9:dd:c25:c25a:d00a:e922
362c19:dd:d9:dd:c25:c25a:d00a:e923/1282c19:dd:d9:dd:c25:c25a:d00a:e923
372c19:dd:d9:dd:c25:c25a:d00a:e924/1282c19:dd:d9:dd:c25:c25a:d00a:e924
382c19:dd:d9:dd:c25:c25a:d00a:e925/1282c19:dd:d9:dd:c25:c25a:d00a:e925
392c19:dd:d9:dd:c25:c25a:d00a:e926/1282c19:dd:d9:dd:c25:c25a:d00a:e926
402c19:dd:d9:dd:c25:c25a:d00a:e927/1282c19:dd:d9:dd:c25:c25a:d00a:e927
412c19:dd:d9:dd:c25:c25a:d00a:e928/1282c19:dd:d9:dd:c25:c25a:d00a:e928
422c19:dd:d9:dd:c25:c25a:d00a:e929/1282c19:dd:d9:dd:c25:c25a:d00a:e929
432c19:dd:d9:dd:c25:c25a:d00a:e92a/1282c19:dd:d9:dd:c25:c25a:d00a:e92a
442c19:dd:d9:dd:c25:c25a:d00a:e92b/1282c19:dd:d9:dd:c25:c25a:d00a:e92b
452c19:dd:d9:dd:c25:c25a:d00a:e92c/1282c19:dd:d9:dd:c25:c25a:d00a:e92c
462c19:dd:d9:dd:c25:c25a:d00a:e92d/1282c19:dd:d9:dd:c25:c25a:d00a:e92d
472c19:dd:d9:dd:c25:c25a:d00a:e92e/1282c19:dd:d9:dd:c25:c25a:d00a:e92e
482c19:dd:d9:dd:c25:c25a:d00a:e92f/1282c19:dd:d9:dd:c25:c25a:d00a:e92f
492c19:dd:d9:dd:c25:c25a:d00a:e930/1282c19:dd:d9:dd:c25:c25a:d00a:e930
502c19:dd:d9:dd:c25:c25a:d00a:e931/1282c19:dd:d9:dd:c25:c25a:d00a:e931
512c19:dd:d9:dd:c25:c25a:d00a:e932/1282c19:dd:d9:dd:c25:c25a:d00a:e932
522c19:dd:d9:dd:c25:c25a:d00a:e933/1282c19:dd:d9:dd:c25:c25a:d00a:e933
532c19:dd:d9:dd:c25:c25a:d00a:e934/1282c19:dd:d9:dd:c25:c25a:d00a:e934
542c19:dd:d9:dd:c25:c25a:d00a:e935/1282c19:dd:d9:dd:c25:c25a:d00a:e935
552c19:dd:d9:dd:c25:c25a:d00a:e936/1282c19:dd:d9:dd:c25:c25a:d00a:e936
562c19:dd:d9:dd:c25:c25a:d00a:e937/1282c19:dd:d9:dd:c25:c25a:d00a:e937
572c19:dd:d9:dd:c25:c25a:d00a:e938/1282c19:dd:d9:dd:c25:c25a:d00a:e938
582c19:dd:d9:dd:c25:c25a:d00a:e939/1282c19:dd:d9:dd:c25:c25a:d00a:e939
592c19:dd:d9:dd:c25:c25a:d00a:e93a/1282c19:dd:d9:dd:c25:c25a:d00a:e93a
602c19:dd:d9:dd:c25:c25a:d00a:e93b/1282c19:dd:d9:dd:c25:c25a:d00a:e93b
612c19:dd:d9:dd:c25:c25a:d00a:e93c/1282c19:dd:d9:dd:c25:c25a:d00a:e93c
622c19:dd:d9:dd:c25:c25a:d00a:e93d/1282c19:dd:d9:dd:c25:c25a:d00a:e93d
632c19:dd:d9:dd:c25:c25a:d00a:e93e/1282c19:dd:d9:dd:c25:c25a:d00a:e93e
642c19:dd:d9:dd:c25:c25a:d00a:e93f/1282c19:dd:d9:dd:c25:c25a:d00a:e93f
652c19:dd:d9:dd:c25:c25a:d00a:e940/1282c19:dd:d9:dd:c25:c25a:d00a:e940
662c19:dd:d9:dd:c25:c25a:d00a:e941/1282c19:dd:d9:dd:c25:c25a:d00a:e941
672c19:dd:d9:dd:c25:c25a:d00a:e942/1282c19:dd:d9:dd:c25:c25a:d00a:e942
682c19:dd:d9:dd:c25:c25a:d00a:e943/1282c19:dd:d9:dd:c25:c25a:d00a:e943
692c19:dd:d9:dd:c25:c25a:d00a:e944/1282c19:dd:d9:dd:c25:c25a:d00a:e944
702c19:dd:d9:dd:c25:c25a:d00a:e945/1282c19:dd:d9:dd:c25:c25a:d00a:e945
712c19:dd:d9:dd:c25:c25a:d00a:e946/1282c19:dd:d9:dd:c25:c25a:d00a:e946
722c19:dd:d9:dd:c25:c25a:d00a:e947/1282c19:dd:d9:dd:c25:c25a:d00a:e947
732c19:dd:d9:dd:c25:c25a:d00a:e948/1282c19:dd:d9:dd:c25:c25a:d00a:e948
742c19:dd:d9:dd:c25:c25a:d00a:e949/1282c19:dd:d9:dd:c25:c25a:d00a:e949
752c19:dd:d9:dd:c25:c25a:d00a:e94a/1282c19:dd:d9:dd:c25:c25a:d00a:e94a
762c19:dd:d9:dd:c25:c25a:d00a:e94b/1282c19:dd:d9:dd:c25:c25a:d00a:e94b
772c19:dd:d9:dd:c25:c25a:d00a:e94c/1282c19:dd:d9:dd:c25:c25a:d00a:e94c
782c19:dd:d9:dd:c25:c25a:d00a:e94d/1282c19:dd:d9:dd:c25:c25a:d00a:e94d
792c19:dd:d9:dd:c25:c25a:d00a:e94e/1282c19:dd:d9:dd:c25:c25a:d00a:e94e
802c19:dd:d9:dd:c25:c25a:d00a:e94f/1282c19:dd:d9:dd:c25:c25a:d00a:e94f
812c19:dd:d9:dd:c25:c25a:d00a:e950/1282c19:dd:d9:dd:c25:c25a:d00a:e950
822c19:dd:d9:dd:c25:c25a:d00a:e951/1282c19:dd:d9:dd:c25:c25a:d00a:e951
832c19:dd:d9:dd:c25:c25a:d00a:e952/1282c19:dd:d9:dd:c25:c25a:d00a:e952
842c19:dd:d9:dd:c25:c25a:d00a:e953/1282c19:dd:d9:dd:c25:c25a:d00a:e953
852c19:dd:d9:dd:c25:c25a:d00a:e954/1282c19:dd:d9:dd:c25:c25a:d00a:e954
862c19:dd:d9:dd:c25:c25a:d00a:e955/1282c19:dd:d9:dd:c25:c25a:d00a:e955
872c19:dd:d9:dd:c25:c25a:d00a:e956/1282c19:dd:d9:dd:c25:c25a:d00a:e956
882c19:dd:d9:dd:c25:c25a:d00a:e957/1282c19:dd:d9:dd:c25:c25a:d00a:e957
892c19:dd:d9:dd:c25:c25a:d00a:e958/1282c19:dd:d9:dd:c25:c25a:d00a:e958
902c19:dd:d9:dd:c25:c25a:d00a:e959/1282c19:dd:d9:dd:c25:c25a:d00a:e959
912c19:dd:d9:dd:c25:c25a:d00a:e95a/1282c19:dd:d9:dd:c25:c25a:d00a:e95a
922c19:dd:d9:dd:c25:c25a:d00a:e95b/1282c19:dd:d9:dd:c25:c25a:d00a:e95b
932c19:dd:d9:dd:c25:c25a:d00a:e95c/1282c19:dd:d9:dd:c25:c25a:d00a:e95c
942c19:dd:d9:dd:c25:c25a:d00a:e95d/1282c19:dd:d9:dd:c25:c25a:d00a:e95d
952c19:dd:d9:dd:c25:c25a:d00a:e95e/1282c19:dd:d9:dd:c25:c25a:d00a:e95e
962c19:dd:d9:dd:c25:c25a:d00a:e95f/1282c19:dd:d9:dd:c25:c25a:d00a:e95f
972c19:dd:d9:dd:c25:c25a:d00a:e960/1282c19:dd:d9:dd:c25:c25a:d00a:e960
982c19:dd:d9:dd:c25:c25a:d00a:e961/1282c19:dd:d9:dd:c25:c25a:d00a:e961
992c19:dd:d9:dd:c25:c25a:d00a:e962/1282c19:dd:d9:dd:c25:c25a:d00a:e962
1002c19:dd:d9:dd:c25:c25a:d00a:e963/1282c19:dd:d9:dd:c25:c25a:d00a:e963
1012c19:dd:d9:dd:c25:c25a:d00a:e964/1282c19:dd:d9:dd:c25:c25a:d00a:e964
1022c19:dd:d9:dd:c25:c25a:d00a:e965/1282c19:dd:d9:dd:c25:c25a:d00a:e965
1032c19:dd:d9:dd:c25:c25a:d00a:e966/1282c19:dd:d9:dd:c25:c25a:d00a:e966
1042c19:dd:d9:dd:c25:c25a:d00a:e967/1282c19:dd:d9:dd:c25:c25a:d00a:e967
1052c19:dd:d9:dd:c25:c25a:d00a:e968/1282c19:dd:d9:dd:c25:c25a:d00a:e968
1062c19:dd:d9:dd:c25:c25a:d00a:e969/1282c19:dd:d9:dd:c25:c25a:d00a:e969
1072c19:dd:d9:dd:c25:c25a:d00a:e96a/1282c19:dd:d9:dd:c25:c25a:d00a:e96a
1082c19:dd:d9:dd:c25:c25a:d00a:e96b/1282c19:dd:d9:dd:c25:c25a:d00a:e96b
1092c19:dd:d9:dd:c25:c25a:d00a:e96c/1282c19:dd:d9:dd:c25:c25a:d00a:e96c
1102c19:dd:d9:dd:c25:c25a:d00a:e96d/1282c19:dd:d9:dd:c25:c25a:d00a:e96d
1112c19:dd:d9:dd:c25:c25a:d00a:e96e/1282c19:dd:d9:dd:c25:c25a:d00a:e96e
1122c19:dd:d9:dd:c25:c25a:d00a:e96f/1282c19:dd:d9:dd:c25:c25a:d00a:e96f
1132c19:dd:d9:dd:c25:c25a:d00a:e970/1282c19:dd:d9:dd:c25:c25a:d00a:e970
1142c19:dd:d9:dd:c25:c25a:d00a:e971/1282c19:dd:d9:dd:c25:c25a:d00a:e971
1152c19:dd:d9:dd:c25:c25a:d00a:e972/1282c19:dd:d9:dd:c25:c25a:d00a:e972
1162c19:dd:d9:dd:c25:c25a:d00a:e973/1282c19:dd:d9:dd:c25:c25a:d00a:e973
1172c19:dd:d9:dd:c25:c25a:d00a:e974/1282c19:dd:d9:dd:c25:c25a:d00a:e974
1182c19:dd:d9:dd:c25:c25a:d00a:e975/1282c19:dd:d9:dd:c25:c25a:d00a:e975
1192c19:dd:d9:dd:c25:c25a:d00a:e976/1282c19:dd:d9:dd:c25:c25a:d00a:e976
1202c19:dd:d9:dd:c25:c25a:d00a:e977/1282c19:dd:d9:dd:c25:c25a:d00a:e977
1212c19:dd:d9:dd:c25:c25a:d00a:e978/1282c19:dd:d9:dd:c25:c25a:d00a:e978
1222c19:dd:d9:dd:c25:c25a:d00a:e979/1282c19:dd:d9:dd:c25:c25a:d00a:e979
1232c19:dd:d9:dd:c25:c25a:d00a:e97a/1282c19:dd:d9:dd:c25:c25a:d00a:e97a
1242c19:dd:d9:dd:c25:c25a:d00a:e97b/1282c19:dd:d9:dd:c25:c25a:d00a:e97b
1252c19:dd:d9:dd:c25:c25a:d00a:e97c/1282c19:dd:d9:dd:c25:c25a:d00a:e97c
1262c19:dd:d9:dd:c25:c25a:d00a:e97d/1282c19:dd:d9:dd:c25:c25a:d00a:e97d
1272c19:dd:d9:dd:c25:c25a:d00a:e97e/1282c19:dd:d9:dd:c25:c25a:d00a:e97e
1282c19:dd:d9:dd:c25:c25a:d00a:e97f/1282c19:dd:d9:dd:c25:c25a:d00a:e97f
1292c19:dd:d9:dd:c25:c25a:d00a:e980/1282c19:dd:d9:dd:c25:c25a:d00a:e980
1302c19:dd:d9:dd:c25:c25a:d00a:e981/1282c19:dd:d9:dd:c25:c25a:d00a:e981
1312c19:dd:d9:dd:c25:c25a:d00a:e982/1282c19:dd:d9:dd:c25:c25a:d00a:e982
1322c19:dd:d9:dd:c25:c25a:d00a:e983/1282c19:dd:d9:dd:c25:c25a:d00a:e983
1332c19:dd:d9:dd:c25:c25a:d00a:e984/1282c19:dd:d9:dd:c25:c25a:d00a:e984
1342c19:dd:d9:dd:c25:c25a:d00a:e985/1282c19:dd:d9:dd:c25:c25a:d00a:e985
1352c19:dd:d9:dd:c25:c25a:d00a:e986/1282c19:dd:d9:dd:c25:c25a:d00a:e986
1362c19:dd:d9:dd:c25:c25a:d00a:e987/1282c19:dd:d9:dd:c25:c25a:d00a:e987
1372c19:dd:d9:dd:c25:c25a:d00a:e988/1282c19:dd:d9:dd:c25:c25a:d00a:e988
1382c19:dd:d9:dd:c25:c25a:d00a:e989/1282c19:dd:d9:dd:c25:c25a:d00a:e989
1392c19:dd:d9:dd:c25:c25a:d00a:e98a/1282c19:dd:d9:dd:c25:c25a:d00a:e98a
1402c19:dd:d9:dd:c25:c25a:d00a:e98b/1282c19:dd:d9:dd:c25:c25a:d00a:e98b
1412c19:dd:d9:dd:c25:c25a:d00a:e98c/1282c19:dd:d9:dd:c25:c25a:d00a:e98c
1422c19:dd:d9:dd:c25:c25a:d00a:e98d/1282c19:dd:d9:dd:c25:c25a:d00a:e98d
1432c19:dd:d9:dd:c25:c25a:d00a:e98e/1282c19:dd:d9:dd:c25:c25a:d00a:e98e
1442c19:dd:d9:dd:c25:c25a:d00a:e98f/1282c19:dd:d9:dd:c25:c25a:d00a:e98f
1452c19:dd:d9:dd:c25:c25a:d00a:e990/1282c19:dd:d9:dd:c25:c25a:d00a:e990
1462c19:dd:d9:dd:c25:c25a:d00a:e991/1282c19:dd:d9:dd:c25:c25a:d00a:e991
1472c19:dd:d9:dd:c25:c25a:d00a:e992/1282c19:dd:d9:dd:c25:c25a:d00a:e992
1482c19:dd:d9:dd:c25:c25a:d00a:e993/1282c19:dd:d9:dd:c25:c25a:d00a:e993
1492c19:dd:d9:dd:c25:c25a:d00a:e994/1282c19:dd:d9:dd:c25:c25a:d00a:e994
1502c19:dd:d9:dd:c25:c25a:d00a:e995/1282c19:dd:d9:dd:c25:c25a:d00a:e995
1512c19:dd:d9:dd:c25:c25a:d00a:e996/1282c19:dd:d9:dd:c25:c25a:d00a:e996
1522c19:dd:d9:dd:c25:c25a:d00a:e997/1282c19:dd:d9:dd:c25:c25a:d00a:e997
1532c19:dd:d9:dd:c25:c25a:d00a:e998/1282c19:dd:d9:dd:c25:c25a:d00a:e998
1542c19:dd:d9:dd:c25:c25a:d00a:e999/1282c19:dd:d9:dd:c25:c25a:d00a:e999
1552c19:dd:d9:dd:c25:c25a:d00a:e99a/1282c19:dd:d9:dd:c25:c25a:d00a:e99a
1562c19:dd:d9:dd:c25:c25a:d00a:e99b/1282c19:dd:d9:dd:c25:c25a:d00a:e99b
1572c19:dd:d9:dd:c25:c25a:d00a:e99c/1282c19:dd:d9:dd:c25:c25a:d00a:e99c
1582c19:dd:d9:dd:c25:c25a:d00a:e99d/1282c19:dd:d9:dd:c25:c25a:d00a:e99d
1592c19:dd:d9:dd:c25:c25a:d00a:e99e/1282c19:dd:d9:dd:c25:c25a:d00a:e99e
1602c19:dd:d9:dd:c25:c25a:d00a:e99f/1282c19:dd:d9:dd:c25:c25a:d00a:e99f
1612c19:dd:d9:dd:c25:c25a:d00a:e9a0/1282c19:dd:d9:dd:c25:c25a:d00a:e9a0
1622c19:dd:d9:dd:c25:c25a:d00a:e9a1/1282c19:dd:d9:dd:c25:c25a:d00a:e9a1
1632c19:dd:d9:dd:c25:c25a:d00a:e9a2/1282c19:dd:d9:dd:c25:c25a:d00a:e9a2
1642c19:dd:d9:dd:c25:c25a:d00a:e9a3/1282c19:dd:d9:dd:c25:c25a:d00a:e9a3
1652c19:dd:d9:dd:c25:c25a:d00a:e9a4/1282c19:dd:d9:dd:c25:c25a:d00a:e9a4
1662c19:dd:d9:dd:c25:c25a:d00a:e9a5/1282c19:dd:d9:dd:c25:c25a:d00a:e9a5
1672c19:dd:d9:dd:c25:c25a:d00a:e9a6/1282c19:dd:d9:dd:c25:c25a:d00a:e9a6
1682c19:dd:d9:dd:c25:c25a:d00a:e9a7/1282c19:dd:d9:dd:c25:c25a:d00a:e9a7
1692c19:dd:d9:dd:c25:c25a:d00a:e9a8/1282c19:dd:d9:dd:c25:c25a:d00a:e9a8
1702c19:dd:d9:dd:c25:c25a:d00a:e9a9/1282c19:dd:d9:dd:c25:c25a:d00a:e9a9
1712c19:dd:d9:dd:c25:c25a:d00a:e9aa/1282c19:dd:d9:dd:c25:c25a:d00a:e9aa
1722c19:dd:d9:dd:c25:c25a:d00a:e9ab/1282c19:dd:d9:dd:c25:c25a:d00a:e9ab
1732c19:dd:d9:dd:c25:c25a:d00a:e9ac/1282c19:dd:d9:dd:c25:c25a:d00a:e9ac
1742c19:dd:d9:dd:c25:c25a:d00a:e9ad/1282c19:dd:d9:dd:c25:c25a:d00a:e9ad
1752c19:dd:d9:dd:c25:c25a:d00a:e9ae/1282c19:dd:d9:dd:c25:c25a:d00a:e9ae
1762c19:dd:d9:dd:c25:c25a:d00a:e9af/1282c19:dd:d9:dd:c25:c25a:d00a:e9af
1772c19:dd:d9:dd:c25:c25a:d00a:e9b0/1282c19:dd:d9:dd:c25:c25a:d00a:e9b0
1782c19:dd:d9:dd:c25:c25a:d00a:e9b1/1282c19:dd:d9:dd:c25:c25a:d00a:e9b1
1792c19:dd:d9:dd:c25:c25a:d00a:e9b2/1282c19:dd:d9:dd:c25:c25a:d00a:e9b2
1802c19:dd:d9:dd:c25:c25a:d00a:e9b3/1282c19:dd:d9:dd:c25:c25a:d00a:e9b3
1812c19:dd:d9:dd:c25:c25a:d00a:e9b4/1282c19:dd:d9:dd:c25:c25a:d00a:e9b4
1822c19:dd:d9:dd:c25:c25a:d00a:e9b5/1282c19:dd:d9:dd:c25:c25a:d00a:e9b5
1832c19:dd:d9:dd:c25:c25a:d00a:e9b6/1282c19:dd:d9:dd:c25:c25a:d00a:e9b6
1842c19:dd:d9:dd:c25:c25a:d00a:e9b7/1282c19:dd:d9:dd:c25:c25a:d00a:e9b7
1852c19:dd:d9:dd:c25:c25a:d00a:e9b8/1282c19:dd:d9:dd:c25:c25a:d00a:e9b8
1862c19:dd:d9:dd:c25:c25a:d00a:e9b9/1282c19:dd:d9:dd:c25:c25a:d00a:e9b9
1872c19:dd:d9:dd:c25:c25a:d00a:e9ba/1282c19:dd:d9:dd:c25:c25a:d00a:e9ba
1882c19:dd:d9:dd:c25:c25a:d00a:e9bb/1282c19:dd:d9:dd:c25:c25a:d00a:e9bb
1892c19:dd:d9:dd:c25:c25a:d00a:e9bc/1282c19:dd:d9:dd:c25:c25a:d00a:e9bc
1902c19:dd:d9:dd:c25:c25a:d00a:e9bd/1282c19:dd:d9:dd:c25:c25a:d00a:e9bd
1912c19:dd:d9:dd:c25:c25a:d00a:e9be/1282c19:dd:d9:dd:c25:c25a:d00a:e9be
1922c19:dd:d9:dd:c25:c25a:d00a:e9bf/1282c19:dd:d9:dd:c25:c25a:d00a:e9bf
1932c19:dd:d9:dd:c25:c25a:d00a:e9c0/1282c19:dd:d9:dd:c25:c25a:d00a:e9c0
1942c19:dd:d9:dd:c25:c25a:d00a:e9c1/1282c19:dd:d9:dd:c25:c25a:d00a:e9c1
1952c19:dd:d9:dd:c25:c25a:d00a:e9c2/1282c19:dd:d9:dd:c25:c25a:d00a:e9c2
1962c19:dd:d9:dd:c25:c25a:d00a:e9c3/1282c19:dd:d9:dd:c25:c25a:d00a:e9c3
1972c19:dd:d9:dd:c25:c25a:d00a:e9c4/1282c19:dd:d9:dd:c25:c25a:d00a:e9c4
1982c19:dd:d9:dd:c25:c25a:d00a:e9c5/1282c19:dd:d9:dd:c25:c25a:d00a:e9c5
1992c19:dd:d9:dd:c25:c25a:d00a:e9c6/1282c19:dd:d9:dd:c25:c25a:d00a:e9c6
2002c19:dd:d9:dd:c25:c25a:d00a:e9c7/1282c19:dd:d9:dd:c25:c25a:d00a:e9c7
2012c19:dd:d9:dd:c25:c25a:d00a:e9c8/1282c19:dd:d9:dd:c25:c25a:d00a:e9c8
2022c19:dd:d9:dd:c25:c25a:d00a:e9c9/1282c19:dd:d9:dd:c25:c25a:d00a:e9c9
2032c19:dd:d9:dd:c25:c25a:d00a:e9ca/1282c19:dd:d9:dd:c25:c25a:d00a:e9ca
2042c19:dd:d9:dd:c25:c25a:d00a:e9cb/1282c19:dd:d9:dd:c25:c25a:d00a:e9cb
2052c19:dd:d9:dd:c25:c25a:d00a:e9cc/1282c19:dd:d9:dd:c25:c25a:d00a:e9cc
2062c19:dd:d9:dd:c25:c25a:d00a:e9cd/1282c19:dd:d9:dd:c25:c25a:d00a:e9cd
2072c19:dd:d9:dd:c25:c25a:d00a:e9ce/1282c19:dd:d9:dd:c25:c25a:d00a:e9ce
2082c19:dd:d9:dd:c25:c25a:d00a:e9cf/1282c19:dd:d9:dd:c25:c25a:d00a:e9cf
2092c19:dd:d9:dd:c25:c25a:d00a:e9d0/1282c19:dd:d9:dd:c25:c25a:d00a:e9d0
2102c19:dd:d9:dd:c25:c25a:d00a:e9d1/1282c19:dd:d9:dd:c25:c25a:d00a:e9d1
2112c19:dd:d9:dd:c25:c25a:d00a:e9d2/1282c19:dd:d9:dd:c25:c25a:d00a:e9d2
2122c19:dd:d9:dd:c25:c25a:d00a:e9d3/1282c19:dd:d9:dd:c25:c25a:d00a:e9d3
2132c19:dd:d9:dd:c25:c25a:d00a:e9d4/1282c19:dd:d9:dd:c25:c25a:d00a:e9d4
2142c19:dd:d9:dd:c25:c25a:d00a:e9d5/1282c19:dd:d9:dd:c25:c25a:d00a:e9d5
2152c19:dd:d9:dd:c25:c25a:d00a:e9d6/1282c19:dd:d9:dd:c25:c25a:d00a:e9d6
2162c19:dd:d9:dd:c25:c25a:d00a:e9d7/1282c19:dd:d9:dd:c25:c25a:d00a:e9d7
2172c19:dd:d9:dd:c25:c25a:d00a:e9d8/1282c19:dd:d9:dd:c25:c25a:d00a:e9d8
2182c19:dd:d9:dd:c25:c25a:d00a:e9d9/1282c19:dd:d9:dd:c25:c25a:d00a:e9d9
2192c19:dd:d9:dd:c25:c25a:d00a:e9da/1282c19:dd:d9:dd:c25:c25a:d00a:e9da
2202c19:dd:d9:dd:c25:c25a:d00a:e9db/1282c19:dd:d9:dd:c25:c25a:d00a:e9db
2212c19:dd:d9:dd:c25:c25a:d00a:e9dc/1282c19:dd:d9:dd:c25:c25a:d00a:e9dc
2222c19:dd:d9:dd:c25:c25a:d00a:e9dd/1282c19:dd:d9:dd:c25:c25a:d00a:e9dd
2232c19:dd:d9:dd:c25:c25a:d00a:e9de/1282c19:dd:d9:dd:c25:c25a:d00a:e9de
2242c19:dd:d9:dd:c25:c25a:d00a:e9df/1282c19:dd:d9:dd:c25:c25a:d00a:e9df
2252c19:dd:d9:dd:c25:c25a:d00a:e9e0/1282c19:dd:d9:dd:c25:c25a:d00a:e9e0
2262c19:dd:d9:dd:c25:c25a:d00a:e9e1/1282c19:dd:d9:dd:c25:c25a:d00a:e9e1
2272c19:dd:d9:dd:c25:c25a:d00a:e9e2/1282c19:dd:d9:dd:c25:c25a:d00a:e9e2
2282c19:dd:d9:dd:c25:c25a:d00a:e9e3/1282c19:dd:d9:dd:c25:c25a:d00a:e9e3
2292c19:dd:d9:dd:c25:c25a:d00a:e9e4/1282c19:dd:d9:dd:c25:c25a:d00a:e9e4
2302c19:dd:d9:dd:c25:c25a:d00a:e9e5/1282c19:dd:d9:dd:c25:c25a:d00a:e9e5
2312c19:dd:d9:dd:c25:c25a:d00a:e9e6/1282c19:dd:d9:dd:c25:c25a:d00a:e9e6
2322c19:dd:d9:dd:c25:c25a:d00a:e9e7/1282c19:dd:d9:dd:c25:c25a:d00a:e9e7
2332c19:dd:d9:dd:c25:c25a:d00a:e9e8/1282c19:dd:d9:dd:c25:c25a:d00a:e9e8
2342c19:dd:d9:dd:c25:c25a:d00a:e9e9/1282c19:dd:d9:dd:c25:c25a:d00a:e9e9
2352c19:dd:d9:dd:c25:c25a:d00a:e9ea/1282c19:dd:d9:dd:c25:c25a:d00a:e9ea
2362c19:dd:d9:dd:c25:c25a:d00a:e9eb/1282c19:dd:d9:dd:c25:c25a:d00a:e9eb
2372c19:dd:d9:dd:c25:c25a:d00a:e9ec/1282c19:dd:d9:dd:c25:c25a:d00a:e9ec
2382c19:dd:d9:dd:c25:c25a:d00a:e9ed/1282c19:dd:d9:dd:c25:c25a:d00a:e9ed
2392c19:dd:d9:dd:c25:c25a:d00a:e9ee/1282c19:dd:d9:dd:c25:c25a:d00a:e9ee
2402c19:dd:d9:dd:c25:c25a:d00a:e9ef/1282c19:dd:d9:dd:c25:c25a:d00a:e9ef
2412c19:dd:d9:dd:c25:c25a:d00a:e9f0/1282c19:dd:d9:dd:c25:c25a:d00a:e9f0
2422c19:dd:d9:dd:c25:c25a:d00a:e9f1/1282c19:dd:d9:dd:c25:c25a:d00a:e9f1
2432c19:dd:d9:dd:c25:c25a:d00a:e9f2/1282c19:dd:d9:dd:c25:c25a:d00a:e9f2
2442c19:dd:d9:dd:c25:c25a:d00a:e9f3/1282c19:dd:d9:dd:c25:c25a:d00a:e9f3
2452c19:dd:d9:dd:c25:c25a:d00a:e9f4/1282c19:dd:d9:dd:c25:c25a:d00a:e9f4
2462c19:dd:d9:dd:c25:c25a:d00a:e9f5/1282c19:dd:d9:dd:c25:c25a:d00a:e9f5
2472c19:dd:d9:dd:c25:c25a:d00a:e9f6/1282c19:dd:d9:dd:c25:c25a:d00a:e9f6
2482c19:dd:d9:dd:c25:c25a:d00a:e9f7/1282c19:dd:d9:dd:c25:c25a:d00a:e9f7
2492c19:dd:d9:dd:c25:c25a:d00a:e9f8/1282c19:dd:d9:dd:c25:c25a:d00a:e9f8
2502c19:dd:d9:dd:c25:c25a:d00a:e9f9/1282c19:dd:d9:dd:c25:c25a:d00a:e9f9
2512c19:dd:d9:dd:c25:c25a:d00a:e9fa/1282c19:dd:d9:dd:c25:c25a:d00a:e9fa
2522c19:dd:d9:dd:c25:c25a:d00a:e9fb/1282c19:dd:d9:dd:c25:c25a:d00a:e9fb
2532c19:dd:d9:dd:c25:c25a:d00a:e9fc/1282c19:dd:d9:dd:c25:c25a:d00a:e9fc
2542c19:dd:d9:dd:c25:c25a:d00a:e9fd/1282c19:dd:d9:dd:c25:c25a:d00a:e9fd
2552c19:dd:d9:dd:c25:c25a:d00a:e9fe/1282c19:dd:d9:dd:c25:c25a:d00a:e9fe
2562c19:dd:d9:dd:c25:c25a:d00a:e9ff/1282c19:dd:d9:dd:c25:c25a:d00a:e9ff

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.