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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:c25:94de:a900/120
First address
2c19:dd:d9:dd:c25:c25:94de:a900
Last address
2c19:dd:d9:dd:c25:c25:94de:a9ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:a900
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.a.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:94de:a900/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:a900/1282c19:dd:d9:dd:c25:c25:94de:a900
22c19:dd:d9:dd:c25:c25:94de:a901/1282c19:dd:d9:dd:c25:c25:94de:a901
32c19:dd:d9:dd:c25:c25:94de:a902/1282c19:dd:d9:dd:c25:c25:94de:a902
42c19:dd:d9:dd:c25:c25:94de:a903/1282c19:dd:d9:dd:c25:c25:94de:a903
52c19:dd:d9:dd:c25:c25:94de:a904/1282c19:dd:d9:dd:c25:c25:94de:a904
62c19:dd:d9:dd:c25:c25:94de:a905/1282c19:dd:d9:dd:c25:c25:94de:a905
72c19:dd:d9:dd:c25:c25:94de:a906/1282c19:dd:d9:dd:c25:c25:94de:a906
82c19:dd:d9:dd:c25:c25:94de:a907/1282c19:dd:d9:dd:c25:c25:94de:a907
92c19:dd:d9:dd:c25:c25:94de:a908/1282c19:dd:d9:dd:c25:c25:94de:a908
102c19:dd:d9:dd:c25:c25:94de:a909/1282c19:dd:d9:dd:c25:c25:94de:a909
112c19:dd:d9:dd:c25:c25:94de:a90a/1282c19:dd:d9:dd:c25:c25:94de:a90a
122c19:dd:d9:dd:c25:c25:94de:a90b/1282c19:dd:d9:dd:c25:c25:94de:a90b
132c19:dd:d9:dd:c25:c25:94de:a90c/1282c19:dd:d9:dd:c25:c25:94de:a90c
142c19:dd:d9:dd:c25:c25:94de:a90d/1282c19:dd:d9:dd:c25:c25:94de:a90d
152c19:dd:d9:dd:c25:c25:94de:a90e/1282c19:dd:d9:dd:c25:c25:94de:a90e
162c19:dd:d9:dd:c25:c25:94de:a90f/1282c19:dd:d9:dd:c25:c25:94de:a90f
172c19:dd:d9:dd:c25:c25:94de:a910/1282c19:dd:d9:dd:c25:c25:94de:a910
182c19:dd:d9:dd:c25:c25:94de:a911/1282c19:dd:d9:dd:c25:c25:94de:a911
192c19:dd:d9:dd:c25:c25:94de:a912/1282c19:dd:d9:dd:c25:c25:94de:a912
202c19:dd:d9:dd:c25:c25:94de:a913/1282c19:dd:d9:dd:c25:c25:94de:a913
212c19:dd:d9:dd:c25:c25:94de:a914/1282c19:dd:d9:dd:c25:c25:94de:a914
222c19:dd:d9:dd:c25:c25:94de:a915/1282c19:dd:d9:dd:c25:c25:94de:a915
232c19:dd:d9:dd:c25:c25:94de:a916/1282c19:dd:d9:dd:c25:c25:94de:a916
242c19:dd:d9:dd:c25:c25:94de:a917/1282c19:dd:d9:dd:c25:c25:94de:a917
252c19:dd:d9:dd:c25:c25:94de:a918/1282c19:dd:d9:dd:c25:c25:94de:a918
262c19:dd:d9:dd:c25:c25:94de:a919/1282c19:dd:d9:dd:c25:c25:94de:a919
272c19:dd:d9:dd:c25:c25:94de:a91a/1282c19:dd:d9:dd:c25:c25:94de:a91a
282c19:dd:d9:dd:c25:c25:94de:a91b/1282c19:dd:d9:dd:c25:c25:94de:a91b
292c19:dd:d9:dd:c25:c25:94de:a91c/1282c19:dd:d9:dd:c25:c25:94de:a91c
302c19:dd:d9:dd:c25:c25:94de:a91d/1282c19:dd:d9:dd:c25:c25:94de:a91d
312c19:dd:d9:dd:c25:c25:94de:a91e/1282c19:dd:d9:dd:c25:c25:94de:a91e
322c19:dd:d9:dd:c25:c25:94de:a91f/1282c19:dd:d9:dd:c25:c25:94de:a91f
332c19:dd:d9:dd:c25:c25:94de:a920/1282c19:dd:d9:dd:c25:c25:94de:a920
342c19:dd:d9:dd:c25:c25:94de:a921/1282c19:dd:d9:dd:c25:c25:94de:a921
352c19:dd:d9:dd:c25:c25:94de:a922/1282c19:dd:d9:dd:c25:c25:94de:a922
362c19:dd:d9:dd:c25:c25:94de:a923/1282c19:dd:d9:dd:c25:c25:94de:a923
372c19:dd:d9:dd:c25:c25:94de:a924/1282c19:dd:d9:dd:c25:c25:94de:a924
382c19:dd:d9:dd:c25:c25:94de:a925/1282c19:dd:d9:dd:c25:c25:94de:a925
392c19:dd:d9:dd:c25:c25:94de:a926/1282c19:dd:d9:dd:c25:c25:94de:a926
402c19:dd:d9:dd:c25:c25:94de:a927/1282c19:dd:d9:dd:c25:c25:94de:a927
412c19:dd:d9:dd:c25:c25:94de:a928/1282c19:dd:d9:dd:c25:c25:94de:a928
422c19:dd:d9:dd:c25:c25:94de:a929/1282c19:dd:d9:dd:c25:c25:94de:a929
432c19:dd:d9:dd:c25:c25:94de:a92a/1282c19:dd:d9:dd:c25:c25:94de:a92a
442c19:dd:d9:dd:c25:c25:94de:a92b/1282c19:dd:d9:dd:c25:c25:94de:a92b
452c19:dd:d9:dd:c25:c25:94de:a92c/1282c19:dd:d9:dd:c25:c25:94de:a92c
462c19:dd:d9:dd:c25:c25:94de:a92d/1282c19:dd:d9:dd:c25:c25:94de:a92d
472c19:dd:d9:dd:c25:c25:94de:a92e/1282c19:dd:d9:dd:c25:c25:94de:a92e
482c19:dd:d9:dd:c25:c25:94de:a92f/1282c19:dd:d9:dd:c25:c25:94de:a92f
492c19:dd:d9:dd:c25:c25:94de:a930/1282c19:dd:d9:dd:c25:c25:94de:a930
502c19:dd:d9:dd:c25:c25:94de:a931/1282c19:dd:d9:dd:c25:c25:94de:a931
512c19:dd:d9:dd:c25:c25:94de:a932/1282c19:dd:d9:dd:c25:c25:94de:a932
522c19:dd:d9:dd:c25:c25:94de:a933/1282c19:dd:d9:dd:c25:c25:94de:a933
532c19:dd:d9:dd:c25:c25:94de:a934/1282c19:dd:d9:dd:c25:c25:94de:a934
542c19:dd:d9:dd:c25:c25:94de:a935/1282c19:dd:d9:dd:c25:c25:94de:a935
552c19:dd:d9:dd:c25:c25:94de:a936/1282c19:dd:d9:dd:c25:c25:94de:a936
562c19:dd:d9:dd:c25:c25:94de:a937/1282c19:dd:d9:dd:c25:c25:94de:a937
572c19:dd:d9:dd:c25:c25:94de:a938/1282c19:dd:d9:dd:c25:c25:94de:a938
582c19:dd:d9:dd:c25:c25:94de:a939/1282c19:dd:d9:dd:c25:c25:94de:a939
592c19:dd:d9:dd:c25:c25:94de:a93a/1282c19:dd:d9:dd:c25:c25:94de:a93a
602c19:dd:d9:dd:c25:c25:94de:a93b/1282c19:dd:d9:dd:c25:c25:94de:a93b
612c19:dd:d9:dd:c25:c25:94de:a93c/1282c19:dd:d9:dd:c25:c25:94de:a93c
622c19:dd:d9:dd:c25:c25:94de:a93d/1282c19:dd:d9:dd:c25:c25:94de:a93d
632c19:dd:d9:dd:c25:c25:94de:a93e/1282c19:dd:d9:dd:c25:c25:94de:a93e
642c19:dd:d9:dd:c25:c25:94de:a93f/1282c19:dd:d9:dd:c25:c25:94de:a93f
652c19:dd:d9:dd:c25:c25:94de:a940/1282c19:dd:d9:dd:c25:c25:94de:a940
662c19:dd:d9:dd:c25:c25:94de:a941/1282c19:dd:d9:dd:c25:c25:94de:a941
672c19:dd:d9:dd:c25:c25:94de:a942/1282c19:dd:d9:dd:c25:c25:94de:a942
682c19:dd:d9:dd:c25:c25:94de:a943/1282c19:dd:d9:dd:c25:c25:94de:a943
692c19:dd:d9:dd:c25:c25:94de:a944/1282c19:dd:d9:dd:c25:c25:94de:a944
702c19:dd:d9:dd:c25:c25:94de:a945/1282c19:dd:d9:dd:c25:c25:94de:a945
712c19:dd:d9:dd:c25:c25:94de:a946/1282c19:dd:d9:dd:c25:c25:94de:a946
722c19:dd:d9:dd:c25:c25:94de:a947/1282c19:dd:d9:dd:c25:c25:94de:a947
732c19:dd:d9:dd:c25:c25:94de:a948/1282c19:dd:d9:dd:c25:c25:94de:a948
742c19:dd:d9:dd:c25:c25:94de:a949/1282c19:dd:d9:dd:c25:c25:94de:a949
752c19:dd:d9:dd:c25:c25:94de:a94a/1282c19:dd:d9:dd:c25:c25:94de:a94a
762c19:dd:d9:dd:c25:c25:94de:a94b/1282c19:dd:d9:dd:c25:c25:94de:a94b
772c19:dd:d9:dd:c25:c25:94de:a94c/1282c19:dd:d9:dd:c25:c25:94de:a94c
782c19:dd:d9:dd:c25:c25:94de:a94d/1282c19:dd:d9:dd:c25:c25:94de:a94d
792c19:dd:d9:dd:c25:c25:94de:a94e/1282c19:dd:d9:dd:c25:c25:94de:a94e
802c19:dd:d9:dd:c25:c25:94de:a94f/1282c19:dd:d9:dd:c25:c25:94de:a94f
812c19:dd:d9:dd:c25:c25:94de:a950/1282c19:dd:d9:dd:c25:c25:94de:a950
822c19:dd:d9:dd:c25:c25:94de:a951/1282c19:dd:d9:dd:c25:c25:94de:a951
832c19:dd:d9:dd:c25:c25:94de:a952/1282c19:dd:d9:dd:c25:c25:94de:a952
842c19:dd:d9:dd:c25:c25:94de:a953/1282c19:dd:d9:dd:c25:c25:94de:a953
852c19:dd:d9:dd:c25:c25:94de:a954/1282c19:dd:d9:dd:c25:c25:94de:a954
862c19:dd:d9:dd:c25:c25:94de:a955/1282c19:dd:d9:dd:c25:c25:94de:a955
872c19:dd:d9:dd:c25:c25:94de:a956/1282c19:dd:d9:dd:c25:c25:94de:a956
882c19:dd:d9:dd:c25:c25:94de:a957/1282c19:dd:d9:dd:c25:c25:94de:a957
892c19:dd:d9:dd:c25:c25:94de:a958/1282c19:dd:d9:dd:c25:c25:94de:a958
902c19:dd:d9:dd:c25:c25:94de:a959/1282c19:dd:d9:dd:c25:c25:94de:a959
912c19:dd:d9:dd:c25:c25:94de:a95a/1282c19:dd:d9:dd:c25:c25:94de:a95a
922c19:dd:d9:dd:c25:c25:94de:a95b/1282c19:dd:d9:dd:c25:c25:94de:a95b
932c19:dd:d9:dd:c25:c25:94de:a95c/1282c19:dd:d9:dd:c25:c25:94de:a95c
942c19:dd:d9:dd:c25:c25:94de:a95d/1282c19:dd:d9:dd:c25:c25:94de:a95d
952c19:dd:d9:dd:c25:c25:94de:a95e/1282c19:dd:d9:dd:c25:c25:94de:a95e
962c19:dd:d9:dd:c25:c25:94de:a95f/1282c19:dd:d9:dd:c25:c25:94de:a95f
972c19:dd:d9:dd:c25:c25:94de:a960/1282c19:dd:d9:dd:c25:c25:94de:a960
982c19:dd:d9:dd:c25:c25:94de:a961/1282c19:dd:d9:dd:c25:c25:94de:a961
992c19:dd:d9:dd:c25:c25:94de:a962/1282c19:dd:d9:dd:c25:c25:94de:a962
1002c19:dd:d9:dd:c25:c25:94de:a963/1282c19:dd:d9:dd:c25:c25:94de:a963
1012c19:dd:d9:dd:c25:c25:94de:a964/1282c19:dd:d9:dd:c25:c25:94de:a964
1022c19:dd:d9:dd:c25:c25:94de:a965/1282c19:dd:d9:dd:c25:c25:94de:a965
1032c19:dd:d9:dd:c25:c25:94de:a966/1282c19:dd:d9:dd:c25:c25:94de:a966
1042c19:dd:d9:dd:c25:c25:94de:a967/1282c19:dd:d9:dd:c25:c25:94de:a967
1052c19:dd:d9:dd:c25:c25:94de:a968/1282c19:dd:d9:dd:c25:c25:94de:a968
1062c19:dd:d9:dd:c25:c25:94de:a969/1282c19:dd:d9:dd:c25:c25:94de:a969
1072c19:dd:d9:dd:c25:c25:94de:a96a/1282c19:dd:d9:dd:c25:c25:94de:a96a
1082c19:dd:d9:dd:c25:c25:94de:a96b/1282c19:dd:d9:dd:c25:c25:94de:a96b
1092c19:dd:d9:dd:c25:c25:94de:a96c/1282c19:dd:d9:dd:c25:c25:94de:a96c
1102c19:dd:d9:dd:c25:c25:94de:a96d/1282c19:dd:d9:dd:c25:c25:94de:a96d
1112c19:dd:d9:dd:c25:c25:94de:a96e/1282c19:dd:d9:dd:c25:c25:94de:a96e
1122c19:dd:d9:dd:c25:c25:94de:a96f/1282c19:dd:d9:dd:c25:c25:94de:a96f
1132c19:dd:d9:dd:c25:c25:94de:a970/1282c19:dd:d9:dd:c25:c25:94de:a970
1142c19:dd:d9:dd:c25:c25:94de:a971/1282c19:dd:d9:dd:c25:c25:94de:a971
1152c19:dd:d9:dd:c25:c25:94de:a972/1282c19:dd:d9:dd:c25:c25:94de:a972
1162c19:dd:d9:dd:c25:c25:94de:a973/1282c19:dd:d9:dd:c25:c25:94de:a973
1172c19:dd:d9:dd:c25:c25:94de:a974/1282c19:dd:d9:dd:c25:c25:94de:a974
1182c19:dd:d9:dd:c25:c25:94de:a975/1282c19:dd:d9:dd:c25:c25:94de:a975
1192c19:dd:d9:dd:c25:c25:94de:a976/1282c19:dd:d9:dd:c25:c25:94de:a976
1202c19:dd:d9:dd:c25:c25:94de:a977/1282c19:dd:d9:dd:c25:c25:94de:a977
1212c19:dd:d9:dd:c25:c25:94de:a978/1282c19:dd:d9:dd:c25:c25:94de:a978
1222c19:dd:d9:dd:c25:c25:94de:a979/1282c19:dd:d9:dd:c25:c25:94de:a979
1232c19:dd:d9:dd:c25:c25:94de:a97a/1282c19:dd:d9:dd:c25:c25:94de:a97a
1242c19:dd:d9:dd:c25:c25:94de:a97b/1282c19:dd:d9:dd:c25:c25:94de:a97b
1252c19:dd:d9:dd:c25:c25:94de:a97c/1282c19:dd:d9:dd:c25:c25:94de:a97c
1262c19:dd:d9:dd:c25:c25:94de:a97d/1282c19:dd:d9:dd:c25:c25:94de:a97d
1272c19:dd:d9:dd:c25:c25:94de:a97e/1282c19:dd:d9:dd:c25:c25:94de:a97e
1282c19:dd:d9:dd:c25:c25:94de:a97f/1282c19:dd:d9:dd:c25:c25:94de:a97f
1292c19:dd:d9:dd:c25:c25:94de:a980/1282c19:dd:d9:dd:c25:c25:94de:a980
1302c19:dd:d9:dd:c25:c25:94de:a981/1282c19:dd:d9:dd:c25:c25:94de:a981
1312c19:dd:d9:dd:c25:c25:94de:a982/1282c19:dd:d9:dd:c25:c25:94de:a982
1322c19:dd:d9:dd:c25:c25:94de:a983/1282c19:dd:d9:dd:c25:c25:94de:a983
1332c19:dd:d9:dd:c25:c25:94de:a984/1282c19:dd:d9:dd:c25:c25:94de:a984
1342c19:dd:d9:dd:c25:c25:94de:a985/1282c19:dd:d9:dd:c25:c25:94de:a985
1352c19:dd:d9:dd:c25:c25:94de:a986/1282c19:dd:d9:dd:c25:c25:94de:a986
1362c19:dd:d9:dd:c25:c25:94de:a987/1282c19:dd:d9:dd:c25:c25:94de:a987
1372c19:dd:d9:dd:c25:c25:94de:a988/1282c19:dd:d9:dd:c25:c25:94de:a988
1382c19:dd:d9:dd:c25:c25:94de:a989/1282c19:dd:d9:dd:c25:c25:94de:a989
1392c19:dd:d9:dd:c25:c25:94de:a98a/1282c19:dd:d9:dd:c25:c25:94de:a98a
1402c19:dd:d9:dd:c25:c25:94de:a98b/1282c19:dd:d9:dd:c25:c25:94de:a98b
1412c19:dd:d9:dd:c25:c25:94de:a98c/1282c19:dd:d9:dd:c25:c25:94de:a98c
1422c19:dd:d9:dd:c25:c25:94de:a98d/1282c19:dd:d9:dd:c25:c25:94de:a98d
1432c19:dd:d9:dd:c25:c25:94de:a98e/1282c19:dd:d9:dd:c25:c25:94de:a98e
1442c19:dd:d9:dd:c25:c25:94de:a98f/1282c19:dd:d9:dd:c25:c25:94de:a98f
1452c19:dd:d9:dd:c25:c25:94de:a990/1282c19:dd:d9:dd:c25:c25:94de:a990
1462c19:dd:d9:dd:c25:c25:94de:a991/1282c19:dd:d9:dd:c25:c25:94de:a991
1472c19:dd:d9:dd:c25:c25:94de:a992/1282c19:dd:d9:dd:c25:c25:94de:a992
1482c19:dd:d9:dd:c25:c25:94de:a993/1282c19:dd:d9:dd:c25:c25:94de:a993
1492c19:dd:d9:dd:c25:c25:94de:a994/1282c19:dd:d9:dd:c25:c25:94de:a994
1502c19:dd:d9:dd:c25:c25:94de:a995/1282c19:dd:d9:dd:c25:c25:94de:a995
1512c19:dd:d9:dd:c25:c25:94de:a996/1282c19:dd:d9:dd:c25:c25:94de:a996
1522c19:dd:d9:dd:c25:c25:94de:a997/1282c19:dd:d9:dd:c25:c25:94de:a997
1532c19:dd:d9:dd:c25:c25:94de:a998/1282c19:dd:d9:dd:c25:c25:94de:a998
1542c19:dd:d9:dd:c25:c25:94de:a999/1282c19:dd:d9:dd:c25:c25:94de:a999
1552c19:dd:d9:dd:c25:c25:94de:a99a/1282c19:dd:d9:dd:c25:c25:94de:a99a
1562c19:dd:d9:dd:c25:c25:94de:a99b/1282c19:dd:d9:dd:c25:c25:94de:a99b
1572c19:dd:d9:dd:c25:c25:94de:a99c/1282c19:dd:d9:dd:c25:c25:94de:a99c
1582c19:dd:d9:dd:c25:c25:94de:a99d/1282c19:dd:d9:dd:c25:c25:94de:a99d
1592c19:dd:d9:dd:c25:c25:94de:a99e/1282c19:dd:d9:dd:c25:c25:94de:a99e
1602c19:dd:d9:dd:c25:c25:94de:a99f/1282c19:dd:d9:dd:c25:c25:94de:a99f
1612c19:dd:d9:dd:c25:c25:94de:a9a0/1282c19:dd:d9:dd:c25:c25:94de:a9a0
1622c19:dd:d9:dd:c25:c25:94de:a9a1/1282c19:dd:d9:dd:c25:c25:94de:a9a1
1632c19:dd:d9:dd:c25:c25:94de:a9a2/1282c19:dd:d9:dd:c25:c25:94de:a9a2
1642c19:dd:d9:dd:c25:c25:94de:a9a3/1282c19:dd:d9:dd:c25:c25:94de:a9a3
1652c19:dd:d9:dd:c25:c25:94de:a9a4/1282c19:dd:d9:dd:c25:c25:94de:a9a4
1662c19:dd:d9:dd:c25:c25:94de:a9a5/1282c19:dd:d9:dd:c25:c25:94de:a9a5
1672c19:dd:d9:dd:c25:c25:94de:a9a6/1282c19:dd:d9:dd:c25:c25:94de:a9a6
1682c19:dd:d9:dd:c25:c25:94de:a9a7/1282c19:dd:d9:dd:c25:c25:94de:a9a7
1692c19:dd:d9:dd:c25:c25:94de:a9a8/1282c19:dd:d9:dd:c25:c25:94de:a9a8
1702c19:dd:d9:dd:c25:c25:94de:a9a9/1282c19:dd:d9:dd:c25:c25:94de:a9a9
1712c19:dd:d9:dd:c25:c25:94de:a9aa/1282c19:dd:d9:dd:c25:c25:94de:a9aa
1722c19:dd:d9:dd:c25:c25:94de:a9ab/1282c19:dd:d9:dd:c25:c25:94de:a9ab
1732c19:dd:d9:dd:c25:c25:94de:a9ac/1282c19:dd:d9:dd:c25:c25:94de:a9ac
1742c19:dd:d9:dd:c25:c25:94de:a9ad/1282c19:dd:d9:dd:c25:c25:94de:a9ad
1752c19:dd:d9:dd:c25:c25:94de:a9ae/1282c19:dd:d9:dd:c25:c25:94de:a9ae
1762c19:dd:d9:dd:c25:c25:94de:a9af/1282c19:dd:d9:dd:c25:c25:94de:a9af
1772c19:dd:d9:dd:c25:c25:94de:a9b0/1282c19:dd:d9:dd:c25:c25:94de:a9b0
1782c19:dd:d9:dd:c25:c25:94de:a9b1/1282c19:dd:d9:dd:c25:c25:94de:a9b1
1792c19:dd:d9:dd:c25:c25:94de:a9b2/1282c19:dd:d9:dd:c25:c25:94de:a9b2
1802c19:dd:d9:dd:c25:c25:94de:a9b3/1282c19:dd:d9:dd:c25:c25:94de:a9b3
1812c19:dd:d9:dd:c25:c25:94de:a9b4/1282c19:dd:d9:dd:c25:c25:94de:a9b4
1822c19:dd:d9:dd:c25:c25:94de:a9b5/1282c19:dd:d9:dd:c25:c25:94de:a9b5
1832c19:dd:d9:dd:c25:c25:94de:a9b6/1282c19:dd:d9:dd:c25:c25:94de:a9b6
1842c19:dd:d9:dd:c25:c25:94de:a9b7/1282c19:dd:d9:dd:c25:c25:94de:a9b7
1852c19:dd:d9:dd:c25:c25:94de:a9b8/1282c19:dd:d9:dd:c25:c25:94de:a9b8
1862c19:dd:d9:dd:c25:c25:94de:a9b9/1282c19:dd:d9:dd:c25:c25:94de:a9b9
1872c19:dd:d9:dd:c25:c25:94de:a9ba/1282c19:dd:d9:dd:c25:c25:94de:a9ba
1882c19:dd:d9:dd:c25:c25:94de:a9bb/1282c19:dd:d9:dd:c25:c25:94de:a9bb
1892c19:dd:d9:dd:c25:c25:94de:a9bc/1282c19:dd:d9:dd:c25:c25:94de:a9bc
1902c19:dd:d9:dd:c25:c25:94de:a9bd/1282c19:dd:d9:dd:c25:c25:94de:a9bd
1912c19:dd:d9:dd:c25:c25:94de:a9be/1282c19:dd:d9:dd:c25:c25:94de:a9be
1922c19:dd:d9:dd:c25:c25:94de:a9bf/1282c19:dd:d9:dd:c25:c25:94de:a9bf
1932c19:dd:d9:dd:c25:c25:94de:a9c0/1282c19:dd:d9:dd:c25:c25:94de:a9c0
1942c19:dd:d9:dd:c25:c25:94de:a9c1/1282c19:dd:d9:dd:c25:c25:94de:a9c1
1952c19:dd:d9:dd:c25:c25:94de:a9c2/1282c19:dd:d9:dd:c25:c25:94de:a9c2
1962c19:dd:d9:dd:c25:c25:94de:a9c3/1282c19:dd:d9:dd:c25:c25:94de:a9c3
1972c19:dd:d9:dd:c25:c25:94de:a9c4/1282c19:dd:d9:dd:c25:c25:94de:a9c4
1982c19:dd:d9:dd:c25:c25:94de:a9c5/1282c19:dd:d9:dd:c25:c25:94de:a9c5
1992c19:dd:d9:dd:c25:c25:94de:a9c6/1282c19:dd:d9:dd:c25:c25:94de:a9c6
2002c19:dd:d9:dd:c25:c25:94de:a9c7/1282c19:dd:d9:dd:c25:c25:94de:a9c7
2012c19:dd:d9:dd:c25:c25:94de:a9c8/1282c19:dd:d9:dd:c25:c25:94de:a9c8
2022c19:dd:d9:dd:c25:c25:94de:a9c9/1282c19:dd:d9:dd:c25:c25:94de:a9c9
2032c19:dd:d9:dd:c25:c25:94de:a9ca/1282c19:dd:d9:dd:c25:c25:94de:a9ca
2042c19:dd:d9:dd:c25:c25:94de:a9cb/1282c19:dd:d9:dd:c25:c25:94de:a9cb
2052c19:dd:d9:dd:c25:c25:94de:a9cc/1282c19:dd:d9:dd:c25:c25:94de:a9cc
2062c19:dd:d9:dd:c25:c25:94de:a9cd/1282c19:dd:d9:dd:c25:c25:94de:a9cd
2072c19:dd:d9:dd:c25:c25:94de:a9ce/1282c19:dd:d9:dd:c25:c25:94de:a9ce
2082c19:dd:d9:dd:c25:c25:94de:a9cf/1282c19:dd:d9:dd:c25:c25:94de:a9cf
2092c19:dd:d9:dd:c25:c25:94de:a9d0/1282c19:dd:d9:dd:c25:c25:94de:a9d0
2102c19:dd:d9:dd:c25:c25:94de:a9d1/1282c19:dd:d9:dd:c25:c25:94de:a9d1
2112c19:dd:d9:dd:c25:c25:94de:a9d2/1282c19:dd:d9:dd:c25:c25:94de:a9d2
2122c19:dd:d9:dd:c25:c25:94de:a9d3/1282c19:dd:d9:dd:c25:c25:94de:a9d3
2132c19:dd:d9:dd:c25:c25:94de:a9d4/1282c19:dd:d9:dd:c25:c25:94de:a9d4
2142c19:dd:d9:dd:c25:c25:94de:a9d5/1282c19:dd:d9:dd:c25:c25:94de:a9d5
2152c19:dd:d9:dd:c25:c25:94de:a9d6/1282c19:dd:d9:dd:c25:c25:94de:a9d6
2162c19:dd:d9:dd:c25:c25:94de:a9d7/1282c19:dd:d9:dd:c25:c25:94de:a9d7
2172c19:dd:d9:dd:c25:c25:94de:a9d8/1282c19:dd:d9:dd:c25:c25:94de:a9d8
2182c19:dd:d9:dd:c25:c25:94de:a9d9/1282c19:dd:d9:dd:c25:c25:94de:a9d9
2192c19:dd:d9:dd:c25:c25:94de:a9da/1282c19:dd:d9:dd:c25:c25:94de:a9da
2202c19:dd:d9:dd:c25:c25:94de:a9db/1282c19:dd:d9:dd:c25:c25:94de:a9db
2212c19:dd:d9:dd:c25:c25:94de:a9dc/1282c19:dd:d9:dd:c25:c25:94de:a9dc
2222c19:dd:d9:dd:c25:c25:94de:a9dd/1282c19:dd:d9:dd:c25:c25:94de:a9dd
2232c19:dd:d9:dd:c25:c25:94de:a9de/1282c19:dd:d9:dd:c25:c25:94de:a9de
2242c19:dd:d9:dd:c25:c25:94de:a9df/1282c19:dd:d9:dd:c25:c25:94de:a9df
2252c19:dd:d9:dd:c25:c25:94de:a9e0/1282c19:dd:d9:dd:c25:c25:94de:a9e0
2262c19:dd:d9:dd:c25:c25:94de:a9e1/1282c19:dd:d9:dd:c25:c25:94de:a9e1
2272c19:dd:d9:dd:c25:c25:94de:a9e2/1282c19:dd:d9:dd:c25:c25:94de:a9e2
2282c19:dd:d9:dd:c25:c25:94de:a9e3/1282c19:dd:d9:dd:c25:c25:94de:a9e3
2292c19:dd:d9:dd:c25:c25:94de:a9e4/1282c19:dd:d9:dd:c25:c25:94de:a9e4
2302c19:dd:d9:dd:c25:c25:94de:a9e5/1282c19:dd:d9:dd:c25:c25:94de:a9e5
2312c19:dd:d9:dd:c25:c25:94de:a9e6/1282c19:dd:d9:dd:c25:c25:94de:a9e6
2322c19:dd:d9:dd:c25:c25:94de:a9e7/1282c19:dd:d9:dd:c25:c25:94de:a9e7
2332c19:dd:d9:dd:c25:c25:94de:a9e8/1282c19:dd:d9:dd:c25:c25:94de:a9e8
2342c19:dd:d9:dd:c25:c25:94de:a9e9/1282c19:dd:d9:dd:c25:c25:94de:a9e9
2352c19:dd:d9:dd:c25:c25:94de:a9ea/1282c19:dd:d9:dd:c25:c25:94de:a9ea
2362c19:dd:d9:dd:c25:c25:94de:a9eb/1282c19:dd:d9:dd:c25:c25:94de:a9eb
2372c19:dd:d9:dd:c25:c25:94de:a9ec/1282c19:dd:d9:dd:c25:c25:94de:a9ec
2382c19:dd:d9:dd:c25:c25:94de:a9ed/1282c19:dd:d9:dd:c25:c25:94de:a9ed
2392c19:dd:d9:dd:c25:c25:94de:a9ee/1282c19:dd:d9:dd:c25:c25:94de:a9ee
2402c19:dd:d9:dd:c25:c25:94de:a9ef/1282c19:dd:d9:dd:c25:c25:94de:a9ef
2412c19:dd:d9:dd:c25:c25:94de:a9f0/1282c19:dd:d9:dd:c25:c25:94de:a9f0
2422c19:dd:d9:dd:c25:c25:94de:a9f1/1282c19:dd:d9:dd:c25:c25:94de:a9f1
2432c19:dd:d9:dd:c25:c25:94de:a9f2/1282c19:dd:d9:dd:c25:c25:94de:a9f2
2442c19:dd:d9:dd:c25:c25:94de:a9f3/1282c19:dd:d9:dd:c25:c25:94de:a9f3
2452c19:dd:d9:dd:c25:c25:94de:a9f4/1282c19:dd:d9:dd:c25:c25:94de:a9f4
2462c19:dd:d9:dd:c25:c25:94de:a9f5/1282c19:dd:d9:dd:c25:c25:94de:a9f5
2472c19:dd:d9:dd:c25:c25:94de:a9f6/1282c19:dd:d9:dd:c25:c25:94de:a9f6
2482c19:dd:d9:dd:c25:c25:94de:a9f7/1282c19:dd:d9:dd:c25:c25:94de:a9f7
2492c19:dd:d9:dd:c25:c25:94de:a9f8/1282c19:dd:d9:dd:c25:c25:94de:a9f8
2502c19:dd:d9:dd:c25:c25:94de:a9f9/1282c19:dd:d9:dd:c25:c25:94de:a9f9
2512c19:dd:d9:dd:c25:c25:94de:a9fa/1282c19:dd:d9:dd:c25:c25:94de:a9fa
2522c19:dd:d9:dd:c25:c25:94de:a9fb/1282c19:dd:d9:dd:c25:c25:94de:a9fb
2532c19:dd:d9:dd:c25:c25:94de:a9fc/1282c19:dd:d9:dd:c25:c25:94de:a9fc
2542c19:dd:d9:dd:c25:c25:94de:a9fd/1282c19:dd:d9:dd:c25:c25:94de:a9fd
2552c19:dd:d9:dd:c25:c25:94de:a9fe/1282c19:dd:d9:dd:c25:c25:94de:a9fe
2562c19:dd:d9:dd:c25:c25:94de:a9ff/1282c19:dd:d9:dd:c25:c25:94de:a9ff

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.