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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:dd0:ec00:900/120
First address
2c19:dd:d9:dd:c25:dd0:ec00:900
Last address
2c19:dd:d9:dd:c25:dd0:ec00:9ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0dd0:ec00:0900
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.0.0.0.c.e.0.d.d.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:dd0:ec00:900/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:dd0:ec00:900/1282c19:dd:d9:dd:c25:dd0:ec00:900
22c19:dd:d9:dd:c25:dd0:ec00:901/1282c19:dd:d9:dd:c25:dd0:ec00:901
32c19:dd:d9:dd:c25:dd0:ec00:902/1282c19:dd:d9:dd:c25:dd0:ec00:902
42c19:dd:d9:dd:c25:dd0:ec00:903/1282c19:dd:d9:dd:c25:dd0:ec00:903
52c19:dd:d9:dd:c25:dd0:ec00:904/1282c19:dd:d9:dd:c25:dd0:ec00:904
62c19:dd:d9:dd:c25:dd0:ec00:905/1282c19:dd:d9:dd:c25:dd0:ec00:905
72c19:dd:d9:dd:c25:dd0:ec00:906/1282c19:dd:d9:dd:c25:dd0:ec00:906
82c19:dd:d9:dd:c25:dd0:ec00:907/1282c19:dd:d9:dd:c25:dd0:ec00:907
92c19:dd:d9:dd:c25:dd0:ec00:908/1282c19:dd:d9:dd:c25:dd0:ec00:908
102c19:dd:d9:dd:c25:dd0:ec00:909/1282c19:dd:d9:dd:c25:dd0:ec00:909
112c19:dd:d9:dd:c25:dd0:ec00:90a/1282c19:dd:d9:dd:c25:dd0:ec00:90a
122c19:dd:d9:dd:c25:dd0:ec00:90b/1282c19:dd:d9:dd:c25:dd0:ec00:90b
132c19:dd:d9:dd:c25:dd0:ec00:90c/1282c19:dd:d9:dd:c25:dd0:ec00:90c
142c19:dd:d9:dd:c25:dd0:ec00:90d/1282c19:dd:d9:dd:c25:dd0:ec00:90d
152c19:dd:d9:dd:c25:dd0:ec00:90e/1282c19:dd:d9:dd:c25:dd0:ec00:90e
162c19:dd:d9:dd:c25:dd0:ec00:90f/1282c19:dd:d9:dd:c25:dd0:ec00:90f
172c19:dd:d9:dd:c25:dd0:ec00:910/1282c19:dd:d9:dd:c25:dd0:ec00:910
182c19:dd:d9:dd:c25:dd0:ec00:911/1282c19:dd:d9:dd:c25:dd0:ec00:911
192c19:dd:d9:dd:c25:dd0:ec00:912/1282c19:dd:d9:dd:c25:dd0:ec00:912
202c19:dd:d9:dd:c25:dd0:ec00:913/1282c19:dd:d9:dd:c25:dd0:ec00:913
212c19:dd:d9:dd:c25:dd0:ec00:914/1282c19:dd:d9:dd:c25:dd0:ec00:914
222c19:dd:d9:dd:c25:dd0:ec00:915/1282c19:dd:d9:dd:c25:dd0:ec00:915
232c19:dd:d9:dd:c25:dd0:ec00:916/1282c19:dd:d9:dd:c25:dd0:ec00:916
242c19:dd:d9:dd:c25:dd0:ec00:917/1282c19:dd:d9:dd:c25:dd0:ec00:917
252c19:dd:d9:dd:c25:dd0:ec00:918/1282c19:dd:d9:dd:c25:dd0:ec00:918
262c19:dd:d9:dd:c25:dd0:ec00:919/1282c19:dd:d9:dd:c25:dd0:ec00:919
272c19:dd:d9:dd:c25:dd0:ec00:91a/1282c19:dd:d9:dd:c25:dd0:ec00:91a
282c19:dd:d9:dd:c25:dd0:ec00:91b/1282c19:dd:d9:dd:c25:dd0:ec00:91b
292c19:dd:d9:dd:c25:dd0:ec00:91c/1282c19:dd:d9:dd:c25:dd0:ec00:91c
302c19:dd:d9:dd:c25:dd0:ec00:91d/1282c19:dd:d9:dd:c25:dd0:ec00:91d
312c19:dd:d9:dd:c25:dd0:ec00:91e/1282c19:dd:d9:dd:c25:dd0:ec00:91e
322c19:dd:d9:dd:c25:dd0:ec00:91f/1282c19:dd:d9:dd:c25:dd0:ec00:91f
332c19:dd:d9:dd:c25:dd0:ec00:920/1282c19:dd:d9:dd:c25:dd0:ec00:920
342c19:dd:d9:dd:c25:dd0:ec00:921/1282c19:dd:d9:dd:c25:dd0:ec00:921
352c19:dd:d9:dd:c25:dd0:ec00:922/1282c19:dd:d9:dd:c25:dd0:ec00:922
362c19:dd:d9:dd:c25:dd0:ec00:923/1282c19:dd:d9:dd:c25:dd0:ec00:923
372c19:dd:d9:dd:c25:dd0:ec00:924/1282c19:dd:d9:dd:c25:dd0:ec00:924
382c19:dd:d9:dd:c25:dd0:ec00:925/1282c19:dd:d9:dd:c25:dd0:ec00:925
392c19:dd:d9:dd:c25:dd0:ec00:926/1282c19:dd:d9:dd:c25:dd0:ec00:926
402c19:dd:d9:dd:c25:dd0:ec00:927/1282c19:dd:d9:dd:c25:dd0:ec00:927
412c19:dd:d9:dd:c25:dd0:ec00:928/1282c19:dd:d9:dd:c25:dd0:ec00:928
422c19:dd:d9:dd:c25:dd0:ec00:929/1282c19:dd:d9:dd:c25:dd0:ec00:929
432c19:dd:d9:dd:c25:dd0:ec00:92a/1282c19:dd:d9:dd:c25:dd0:ec00:92a
442c19:dd:d9:dd:c25:dd0:ec00:92b/1282c19:dd:d9:dd:c25:dd0:ec00:92b
452c19:dd:d9:dd:c25:dd0:ec00:92c/1282c19:dd:d9:dd:c25:dd0:ec00:92c
462c19:dd:d9:dd:c25:dd0:ec00:92d/1282c19:dd:d9:dd:c25:dd0:ec00:92d
472c19:dd:d9:dd:c25:dd0:ec00:92e/1282c19:dd:d9:dd:c25:dd0:ec00:92e
482c19:dd:d9:dd:c25:dd0:ec00:92f/1282c19:dd:d9:dd:c25:dd0:ec00:92f
492c19:dd:d9:dd:c25:dd0:ec00:930/1282c19:dd:d9:dd:c25:dd0:ec00:930
502c19:dd:d9:dd:c25:dd0:ec00:931/1282c19:dd:d9:dd:c25:dd0:ec00:931
512c19:dd:d9:dd:c25:dd0:ec00:932/1282c19:dd:d9:dd:c25:dd0:ec00:932
522c19:dd:d9:dd:c25:dd0:ec00:933/1282c19:dd:d9:dd:c25:dd0:ec00:933
532c19:dd:d9:dd:c25:dd0:ec00:934/1282c19:dd:d9:dd:c25:dd0:ec00:934
542c19:dd:d9:dd:c25:dd0:ec00:935/1282c19:dd:d9:dd:c25:dd0:ec00:935
552c19:dd:d9:dd:c25:dd0:ec00:936/1282c19:dd:d9:dd:c25:dd0:ec00:936
562c19:dd:d9:dd:c25:dd0:ec00:937/1282c19:dd:d9:dd:c25:dd0:ec00:937
572c19:dd:d9:dd:c25:dd0:ec00:938/1282c19:dd:d9:dd:c25:dd0:ec00:938
582c19:dd:d9:dd:c25:dd0:ec00:939/1282c19:dd:d9:dd:c25:dd0:ec00:939
592c19:dd:d9:dd:c25:dd0:ec00:93a/1282c19:dd:d9:dd:c25:dd0:ec00:93a
602c19:dd:d9:dd:c25:dd0:ec00:93b/1282c19:dd:d9:dd:c25:dd0:ec00:93b
612c19:dd:d9:dd:c25:dd0:ec00:93c/1282c19:dd:d9:dd:c25:dd0:ec00:93c
622c19:dd:d9:dd:c25:dd0:ec00:93d/1282c19:dd:d9:dd:c25:dd0:ec00:93d
632c19:dd:d9:dd:c25:dd0:ec00:93e/1282c19:dd:d9:dd:c25:dd0:ec00:93e
642c19:dd:d9:dd:c25:dd0:ec00:93f/1282c19:dd:d9:dd:c25:dd0:ec00:93f
652c19:dd:d9:dd:c25:dd0:ec00:940/1282c19:dd:d9:dd:c25:dd0:ec00:940
662c19:dd:d9:dd:c25:dd0:ec00:941/1282c19:dd:d9:dd:c25:dd0:ec00:941
672c19:dd:d9:dd:c25:dd0:ec00:942/1282c19:dd:d9:dd:c25:dd0:ec00:942
682c19:dd:d9:dd:c25:dd0:ec00:943/1282c19:dd:d9:dd:c25:dd0:ec00:943
692c19:dd:d9:dd:c25:dd0:ec00:944/1282c19:dd:d9:dd:c25:dd0:ec00:944
702c19:dd:d9:dd:c25:dd0:ec00:945/1282c19:dd:d9:dd:c25:dd0:ec00:945
712c19:dd:d9:dd:c25:dd0:ec00:946/1282c19:dd:d9:dd:c25:dd0:ec00:946
722c19:dd:d9:dd:c25:dd0:ec00:947/1282c19:dd:d9:dd:c25:dd0:ec00:947
732c19:dd:d9:dd:c25:dd0:ec00:948/1282c19:dd:d9:dd:c25:dd0:ec00:948
742c19:dd:d9:dd:c25:dd0:ec00:949/1282c19:dd:d9:dd:c25:dd0:ec00:949
752c19:dd:d9:dd:c25:dd0:ec00:94a/1282c19:dd:d9:dd:c25:dd0:ec00:94a
762c19:dd:d9:dd:c25:dd0:ec00:94b/1282c19:dd:d9:dd:c25:dd0:ec00:94b
772c19:dd:d9:dd:c25:dd0:ec00:94c/1282c19:dd:d9:dd:c25:dd0:ec00:94c
782c19:dd:d9:dd:c25:dd0:ec00:94d/1282c19:dd:d9:dd:c25:dd0:ec00:94d
792c19:dd:d9:dd:c25:dd0:ec00:94e/1282c19:dd:d9:dd:c25:dd0:ec00:94e
802c19:dd:d9:dd:c25:dd0:ec00:94f/1282c19:dd:d9:dd:c25:dd0:ec00:94f
812c19:dd:d9:dd:c25:dd0:ec00:950/1282c19:dd:d9:dd:c25:dd0:ec00:950
822c19:dd:d9:dd:c25:dd0:ec00:951/1282c19:dd:d9:dd:c25:dd0:ec00:951
832c19:dd:d9:dd:c25:dd0:ec00:952/1282c19:dd:d9:dd:c25:dd0:ec00:952
842c19:dd:d9:dd:c25:dd0:ec00:953/1282c19:dd:d9:dd:c25:dd0:ec00:953
852c19:dd:d9:dd:c25:dd0:ec00:954/1282c19:dd:d9:dd:c25:dd0:ec00:954
862c19:dd:d9:dd:c25:dd0:ec00:955/1282c19:dd:d9:dd:c25:dd0:ec00:955
872c19:dd:d9:dd:c25:dd0:ec00:956/1282c19:dd:d9:dd:c25:dd0:ec00:956
882c19:dd:d9:dd:c25:dd0:ec00:957/1282c19:dd:d9:dd:c25:dd0:ec00:957
892c19:dd:d9:dd:c25:dd0:ec00:958/1282c19:dd:d9:dd:c25:dd0:ec00:958
902c19:dd:d9:dd:c25:dd0:ec00:959/1282c19:dd:d9:dd:c25:dd0:ec00:959
912c19:dd:d9:dd:c25:dd0:ec00:95a/1282c19:dd:d9:dd:c25:dd0:ec00:95a
922c19:dd:d9:dd:c25:dd0:ec00:95b/1282c19:dd:d9:dd:c25:dd0:ec00:95b
932c19:dd:d9:dd:c25:dd0:ec00:95c/1282c19:dd:d9:dd:c25:dd0:ec00:95c
942c19:dd:d9:dd:c25:dd0:ec00:95d/1282c19:dd:d9:dd:c25:dd0:ec00:95d
952c19:dd:d9:dd:c25:dd0:ec00:95e/1282c19:dd:d9:dd:c25:dd0:ec00:95e
962c19:dd:d9:dd:c25:dd0:ec00:95f/1282c19:dd:d9:dd:c25:dd0:ec00:95f
972c19:dd:d9:dd:c25:dd0:ec00:960/1282c19:dd:d9:dd:c25:dd0:ec00:960
982c19:dd:d9:dd:c25:dd0:ec00:961/1282c19:dd:d9:dd:c25:dd0:ec00:961
992c19:dd:d9:dd:c25:dd0:ec00:962/1282c19:dd:d9:dd:c25:dd0:ec00:962
1002c19:dd:d9:dd:c25:dd0:ec00:963/1282c19:dd:d9:dd:c25:dd0:ec00:963
1012c19:dd:d9:dd:c25:dd0:ec00:964/1282c19:dd:d9:dd:c25:dd0:ec00:964
1022c19:dd:d9:dd:c25:dd0:ec00:965/1282c19:dd:d9:dd:c25:dd0:ec00:965
1032c19:dd:d9:dd:c25:dd0:ec00:966/1282c19:dd:d9:dd:c25:dd0:ec00:966
1042c19:dd:d9:dd:c25:dd0:ec00:967/1282c19:dd:d9:dd:c25:dd0:ec00:967
1052c19:dd:d9:dd:c25:dd0:ec00:968/1282c19:dd:d9:dd:c25:dd0:ec00:968
1062c19:dd:d9:dd:c25:dd0:ec00:969/1282c19:dd:d9:dd:c25:dd0:ec00:969
1072c19:dd:d9:dd:c25:dd0:ec00:96a/1282c19:dd:d9:dd:c25:dd0:ec00:96a
1082c19:dd:d9:dd:c25:dd0:ec00:96b/1282c19:dd:d9:dd:c25:dd0:ec00:96b
1092c19:dd:d9:dd:c25:dd0:ec00:96c/1282c19:dd:d9:dd:c25:dd0:ec00:96c
1102c19:dd:d9:dd:c25:dd0:ec00:96d/1282c19:dd:d9:dd:c25:dd0:ec00:96d
1112c19:dd:d9:dd:c25:dd0:ec00:96e/1282c19:dd:d9:dd:c25:dd0:ec00:96e
1122c19:dd:d9:dd:c25:dd0:ec00:96f/1282c19:dd:d9:dd:c25:dd0:ec00:96f
1132c19:dd:d9:dd:c25:dd0:ec00:970/1282c19:dd:d9:dd:c25:dd0:ec00:970
1142c19:dd:d9:dd:c25:dd0:ec00:971/1282c19:dd:d9:dd:c25:dd0:ec00:971
1152c19:dd:d9:dd:c25:dd0:ec00:972/1282c19:dd:d9:dd:c25:dd0:ec00:972
1162c19:dd:d9:dd:c25:dd0:ec00:973/1282c19:dd:d9:dd:c25:dd0:ec00:973
1172c19:dd:d9:dd:c25:dd0:ec00:974/1282c19:dd:d9:dd:c25:dd0:ec00:974
1182c19:dd:d9:dd:c25:dd0:ec00:975/1282c19:dd:d9:dd:c25:dd0:ec00:975
1192c19:dd:d9:dd:c25:dd0:ec00:976/1282c19:dd:d9:dd:c25:dd0:ec00:976
1202c19:dd:d9:dd:c25:dd0:ec00:977/1282c19:dd:d9:dd:c25:dd0:ec00:977
1212c19:dd:d9:dd:c25:dd0:ec00:978/1282c19:dd:d9:dd:c25:dd0:ec00:978
1222c19:dd:d9:dd:c25:dd0:ec00:979/1282c19:dd:d9:dd:c25:dd0:ec00:979
1232c19:dd:d9:dd:c25:dd0:ec00:97a/1282c19:dd:d9:dd:c25:dd0:ec00:97a
1242c19:dd:d9:dd:c25:dd0:ec00:97b/1282c19:dd:d9:dd:c25:dd0:ec00:97b
1252c19:dd:d9:dd:c25:dd0:ec00:97c/1282c19:dd:d9:dd:c25:dd0:ec00:97c
1262c19:dd:d9:dd:c25:dd0:ec00:97d/1282c19:dd:d9:dd:c25:dd0:ec00:97d
1272c19:dd:d9:dd:c25:dd0:ec00:97e/1282c19:dd:d9:dd:c25:dd0:ec00:97e
1282c19:dd:d9:dd:c25:dd0:ec00:97f/1282c19:dd:d9:dd:c25:dd0:ec00:97f
1292c19:dd:d9:dd:c25:dd0:ec00:980/1282c19:dd:d9:dd:c25:dd0:ec00:980
1302c19:dd:d9:dd:c25:dd0:ec00:981/1282c19:dd:d9:dd:c25:dd0:ec00:981
1312c19:dd:d9:dd:c25:dd0:ec00:982/1282c19:dd:d9:dd:c25:dd0:ec00:982
1322c19:dd:d9:dd:c25:dd0:ec00:983/1282c19:dd:d9:dd:c25:dd0:ec00:983
1332c19:dd:d9:dd:c25:dd0:ec00:984/1282c19:dd:d9:dd:c25:dd0:ec00:984
1342c19:dd:d9:dd:c25:dd0:ec00:985/1282c19:dd:d9:dd:c25:dd0:ec00:985
1352c19:dd:d9:dd:c25:dd0:ec00:986/1282c19:dd:d9:dd:c25:dd0:ec00:986
1362c19:dd:d9:dd:c25:dd0:ec00:987/1282c19:dd:d9:dd:c25:dd0:ec00:987
1372c19:dd:d9:dd:c25:dd0:ec00:988/1282c19:dd:d9:dd:c25:dd0:ec00:988
1382c19:dd:d9:dd:c25:dd0:ec00:989/1282c19:dd:d9:dd:c25:dd0:ec00:989
1392c19:dd:d9:dd:c25:dd0:ec00:98a/1282c19:dd:d9:dd:c25:dd0:ec00:98a
1402c19:dd:d9:dd:c25:dd0:ec00:98b/1282c19:dd:d9:dd:c25:dd0:ec00:98b
1412c19:dd:d9:dd:c25:dd0:ec00:98c/1282c19:dd:d9:dd:c25:dd0:ec00:98c
1422c19:dd:d9:dd:c25:dd0:ec00:98d/1282c19:dd:d9:dd:c25:dd0:ec00:98d
1432c19:dd:d9:dd:c25:dd0:ec00:98e/1282c19:dd:d9:dd:c25:dd0:ec00:98e
1442c19:dd:d9:dd:c25:dd0:ec00:98f/1282c19:dd:d9:dd:c25:dd0:ec00:98f
1452c19:dd:d9:dd:c25:dd0:ec00:990/1282c19:dd:d9:dd:c25:dd0:ec00:990
1462c19:dd:d9:dd:c25:dd0:ec00:991/1282c19:dd:d9:dd:c25:dd0:ec00:991
1472c19:dd:d9:dd:c25:dd0:ec00:992/1282c19:dd:d9:dd:c25:dd0:ec00:992
1482c19:dd:d9:dd:c25:dd0:ec00:993/1282c19:dd:d9:dd:c25:dd0:ec00:993
1492c19:dd:d9:dd:c25:dd0:ec00:994/1282c19:dd:d9:dd:c25:dd0:ec00:994
1502c19:dd:d9:dd:c25:dd0:ec00:995/1282c19:dd:d9:dd:c25:dd0:ec00:995
1512c19:dd:d9:dd:c25:dd0:ec00:996/1282c19:dd:d9:dd:c25:dd0:ec00:996
1522c19:dd:d9:dd:c25:dd0:ec00:997/1282c19:dd:d9:dd:c25:dd0:ec00:997
1532c19:dd:d9:dd:c25:dd0:ec00:998/1282c19:dd:d9:dd:c25:dd0:ec00:998
1542c19:dd:d9:dd:c25:dd0:ec00:999/1282c19:dd:d9:dd:c25:dd0:ec00:999
1552c19:dd:d9:dd:c25:dd0:ec00:99a/1282c19:dd:d9:dd:c25:dd0:ec00:99a
1562c19:dd:d9:dd:c25:dd0:ec00:99b/1282c19:dd:d9:dd:c25:dd0:ec00:99b
1572c19:dd:d9:dd:c25:dd0:ec00:99c/1282c19:dd:d9:dd:c25:dd0:ec00:99c
1582c19:dd:d9:dd:c25:dd0:ec00:99d/1282c19:dd:d9:dd:c25:dd0:ec00:99d
1592c19:dd:d9:dd:c25:dd0:ec00:99e/1282c19:dd:d9:dd:c25:dd0:ec00:99e
1602c19:dd:d9:dd:c25:dd0:ec00:99f/1282c19:dd:d9:dd:c25:dd0:ec00:99f
1612c19:dd:d9:dd:c25:dd0:ec00:9a0/1282c19:dd:d9:dd:c25:dd0:ec00:9a0
1622c19:dd:d9:dd:c25:dd0:ec00:9a1/1282c19:dd:d9:dd:c25:dd0:ec00:9a1
1632c19:dd:d9:dd:c25:dd0:ec00:9a2/1282c19:dd:d9:dd:c25:dd0:ec00:9a2
1642c19:dd:d9:dd:c25:dd0:ec00:9a3/1282c19:dd:d9:dd:c25:dd0:ec00:9a3
1652c19:dd:d9:dd:c25:dd0:ec00:9a4/1282c19:dd:d9:dd:c25:dd0:ec00:9a4
1662c19:dd:d9:dd:c25:dd0:ec00:9a5/1282c19:dd:d9:dd:c25:dd0:ec00:9a5
1672c19:dd:d9:dd:c25:dd0:ec00:9a6/1282c19:dd:d9:dd:c25:dd0:ec00:9a6
1682c19:dd:d9:dd:c25:dd0:ec00:9a7/1282c19:dd:d9:dd:c25:dd0:ec00:9a7
1692c19:dd:d9:dd:c25:dd0:ec00:9a8/1282c19:dd:d9:dd:c25:dd0:ec00:9a8
1702c19:dd:d9:dd:c25:dd0:ec00:9a9/1282c19:dd:d9:dd:c25:dd0:ec00:9a9
1712c19:dd:d9:dd:c25:dd0:ec00:9aa/1282c19:dd:d9:dd:c25:dd0:ec00:9aa
1722c19:dd:d9:dd:c25:dd0:ec00:9ab/1282c19:dd:d9:dd:c25:dd0:ec00:9ab
1732c19:dd:d9:dd:c25:dd0:ec00:9ac/1282c19:dd:d9:dd:c25:dd0:ec00:9ac
1742c19:dd:d9:dd:c25:dd0:ec00:9ad/1282c19:dd:d9:dd:c25:dd0:ec00:9ad
1752c19:dd:d9:dd:c25:dd0:ec00:9ae/1282c19:dd:d9:dd:c25:dd0:ec00:9ae
1762c19:dd:d9:dd:c25:dd0:ec00:9af/1282c19:dd:d9:dd:c25:dd0:ec00:9af
1772c19:dd:d9:dd:c25:dd0:ec00:9b0/1282c19:dd:d9:dd:c25:dd0:ec00:9b0
1782c19:dd:d9:dd:c25:dd0:ec00:9b1/1282c19:dd:d9:dd:c25:dd0:ec00:9b1
1792c19:dd:d9:dd:c25:dd0:ec00:9b2/1282c19:dd:d9:dd:c25:dd0:ec00:9b2
1802c19:dd:d9:dd:c25:dd0:ec00:9b3/1282c19:dd:d9:dd:c25:dd0:ec00:9b3
1812c19:dd:d9:dd:c25:dd0:ec00:9b4/1282c19:dd:d9:dd:c25:dd0:ec00:9b4
1822c19:dd:d9:dd:c25:dd0:ec00:9b5/1282c19:dd:d9:dd:c25:dd0:ec00:9b5
1832c19:dd:d9:dd:c25:dd0:ec00:9b6/1282c19:dd:d9:dd:c25:dd0:ec00:9b6
1842c19:dd:d9:dd:c25:dd0:ec00:9b7/1282c19:dd:d9:dd:c25:dd0:ec00:9b7
1852c19:dd:d9:dd:c25:dd0:ec00:9b8/1282c19:dd:d9:dd:c25:dd0:ec00:9b8
1862c19:dd:d9:dd:c25:dd0:ec00:9b9/1282c19:dd:d9:dd:c25:dd0:ec00:9b9
1872c19:dd:d9:dd:c25:dd0:ec00:9ba/1282c19:dd:d9:dd:c25:dd0:ec00:9ba
1882c19:dd:d9:dd:c25:dd0:ec00:9bb/1282c19:dd:d9:dd:c25:dd0:ec00:9bb
1892c19:dd:d9:dd:c25:dd0:ec00:9bc/1282c19:dd:d9:dd:c25:dd0:ec00:9bc
1902c19:dd:d9:dd:c25:dd0:ec00:9bd/1282c19:dd:d9:dd:c25:dd0:ec00:9bd
1912c19:dd:d9:dd:c25:dd0:ec00:9be/1282c19:dd:d9:dd:c25:dd0:ec00:9be
1922c19:dd:d9:dd:c25:dd0:ec00:9bf/1282c19:dd:d9:dd:c25:dd0:ec00:9bf
1932c19:dd:d9:dd:c25:dd0:ec00:9c0/1282c19:dd:d9:dd:c25:dd0:ec00:9c0
1942c19:dd:d9:dd:c25:dd0:ec00:9c1/1282c19:dd:d9:dd:c25:dd0:ec00:9c1
1952c19:dd:d9:dd:c25:dd0:ec00:9c2/1282c19:dd:d9:dd:c25:dd0:ec00:9c2
1962c19:dd:d9:dd:c25:dd0:ec00:9c3/1282c19:dd:d9:dd:c25:dd0:ec00:9c3
1972c19:dd:d9:dd:c25:dd0:ec00:9c4/1282c19:dd:d9:dd:c25:dd0:ec00:9c4
1982c19:dd:d9:dd:c25:dd0:ec00:9c5/1282c19:dd:d9:dd:c25:dd0:ec00:9c5
1992c19:dd:d9:dd:c25:dd0:ec00:9c6/1282c19:dd:d9:dd:c25:dd0:ec00:9c6
2002c19:dd:d9:dd:c25:dd0:ec00:9c7/1282c19:dd:d9:dd:c25:dd0:ec00:9c7
2012c19:dd:d9:dd:c25:dd0:ec00:9c8/1282c19:dd:d9:dd:c25:dd0:ec00:9c8
2022c19:dd:d9:dd:c25:dd0:ec00:9c9/1282c19:dd:d9:dd:c25:dd0:ec00:9c9
2032c19:dd:d9:dd:c25:dd0:ec00:9ca/1282c19:dd:d9:dd:c25:dd0:ec00:9ca
2042c19:dd:d9:dd:c25:dd0:ec00:9cb/1282c19:dd:d9:dd:c25:dd0:ec00:9cb
2052c19:dd:d9:dd:c25:dd0:ec00:9cc/1282c19:dd:d9:dd:c25:dd0:ec00:9cc
2062c19:dd:d9:dd:c25:dd0:ec00:9cd/1282c19:dd:d9:dd:c25:dd0:ec00:9cd
2072c19:dd:d9:dd:c25:dd0:ec00:9ce/1282c19:dd:d9:dd:c25:dd0:ec00:9ce
2082c19:dd:d9:dd:c25:dd0:ec00:9cf/1282c19:dd:d9:dd:c25:dd0:ec00:9cf
2092c19:dd:d9:dd:c25:dd0:ec00:9d0/1282c19:dd:d9:dd:c25:dd0:ec00:9d0
2102c19:dd:d9:dd:c25:dd0:ec00:9d1/1282c19:dd:d9:dd:c25:dd0:ec00:9d1
2112c19:dd:d9:dd:c25:dd0:ec00:9d2/1282c19:dd:d9:dd:c25:dd0:ec00:9d2
2122c19:dd:d9:dd:c25:dd0:ec00:9d3/1282c19:dd:d9:dd:c25:dd0:ec00:9d3
2132c19:dd:d9:dd:c25:dd0:ec00:9d4/1282c19:dd:d9:dd:c25:dd0:ec00:9d4
2142c19:dd:d9:dd:c25:dd0:ec00:9d5/1282c19:dd:d9:dd:c25:dd0:ec00:9d5
2152c19:dd:d9:dd:c25:dd0:ec00:9d6/1282c19:dd:d9:dd:c25:dd0:ec00:9d6
2162c19:dd:d9:dd:c25:dd0:ec00:9d7/1282c19:dd:d9:dd:c25:dd0:ec00:9d7
2172c19:dd:d9:dd:c25:dd0:ec00:9d8/1282c19:dd:d9:dd:c25:dd0:ec00:9d8
2182c19:dd:d9:dd:c25:dd0:ec00:9d9/1282c19:dd:d9:dd:c25:dd0:ec00:9d9
2192c19:dd:d9:dd:c25:dd0:ec00:9da/1282c19:dd:d9:dd:c25:dd0:ec00:9da
2202c19:dd:d9:dd:c25:dd0:ec00:9db/1282c19:dd:d9:dd:c25:dd0:ec00:9db
2212c19:dd:d9:dd:c25:dd0:ec00:9dc/1282c19:dd:d9:dd:c25:dd0:ec00:9dc
2222c19:dd:d9:dd:c25:dd0:ec00:9dd/1282c19:dd:d9:dd:c25:dd0:ec00:9dd
2232c19:dd:d9:dd:c25:dd0:ec00:9de/1282c19:dd:d9:dd:c25:dd0:ec00:9de
2242c19:dd:d9:dd:c25:dd0:ec00:9df/1282c19:dd:d9:dd:c25:dd0:ec00:9df
2252c19:dd:d9:dd:c25:dd0:ec00:9e0/1282c19:dd:d9:dd:c25:dd0:ec00:9e0
2262c19:dd:d9:dd:c25:dd0:ec00:9e1/1282c19:dd:d9:dd:c25:dd0:ec00:9e1
2272c19:dd:d9:dd:c25:dd0:ec00:9e2/1282c19:dd:d9:dd:c25:dd0:ec00:9e2
2282c19:dd:d9:dd:c25:dd0:ec00:9e3/1282c19:dd:d9:dd:c25:dd0:ec00:9e3
2292c19:dd:d9:dd:c25:dd0:ec00:9e4/1282c19:dd:d9:dd:c25:dd0:ec00:9e4
2302c19:dd:d9:dd:c25:dd0:ec00:9e5/1282c19:dd:d9:dd:c25:dd0:ec00:9e5
2312c19:dd:d9:dd:c25:dd0:ec00:9e6/1282c19:dd:d9:dd:c25:dd0:ec00:9e6
2322c19:dd:d9:dd:c25:dd0:ec00:9e7/1282c19:dd:d9:dd:c25:dd0:ec00:9e7
2332c19:dd:d9:dd:c25:dd0:ec00:9e8/1282c19:dd:d9:dd:c25:dd0:ec00:9e8
2342c19:dd:d9:dd:c25:dd0:ec00:9e9/1282c19:dd:d9:dd:c25:dd0:ec00:9e9
2352c19:dd:d9:dd:c25:dd0:ec00:9ea/1282c19:dd:d9:dd:c25:dd0:ec00:9ea
2362c19:dd:d9:dd:c25:dd0:ec00:9eb/1282c19:dd:d9:dd:c25:dd0:ec00:9eb
2372c19:dd:d9:dd:c25:dd0:ec00:9ec/1282c19:dd:d9:dd:c25:dd0:ec00:9ec
2382c19:dd:d9:dd:c25:dd0:ec00:9ed/1282c19:dd:d9:dd:c25:dd0:ec00:9ed
2392c19:dd:d9:dd:c25:dd0:ec00:9ee/1282c19:dd:d9:dd:c25:dd0:ec00:9ee
2402c19:dd:d9:dd:c25:dd0:ec00:9ef/1282c19:dd:d9:dd:c25:dd0:ec00:9ef
2412c19:dd:d9:dd:c25:dd0:ec00:9f0/1282c19:dd:d9:dd:c25:dd0:ec00:9f0
2422c19:dd:d9:dd:c25:dd0:ec00:9f1/1282c19:dd:d9:dd:c25:dd0:ec00:9f1
2432c19:dd:d9:dd:c25:dd0:ec00:9f2/1282c19:dd:d9:dd:c25:dd0:ec00:9f2
2442c19:dd:d9:dd:c25:dd0:ec00:9f3/1282c19:dd:d9:dd:c25:dd0:ec00:9f3
2452c19:dd:d9:dd:c25:dd0:ec00:9f4/1282c19:dd:d9:dd:c25:dd0:ec00:9f4
2462c19:dd:d9:dd:c25:dd0:ec00:9f5/1282c19:dd:d9:dd:c25:dd0:ec00:9f5
2472c19:dd:d9:dd:c25:dd0:ec00:9f6/1282c19:dd:d9:dd:c25:dd0:ec00:9f6
2482c19:dd:d9:dd:c25:dd0:ec00:9f7/1282c19:dd:d9:dd:c25:dd0:ec00:9f7
2492c19:dd:d9:dd:c25:dd0:ec00:9f8/1282c19:dd:d9:dd:c25:dd0:ec00:9f8
2502c19:dd:d9:dd:c25:dd0:ec00:9f9/1282c19:dd:d9:dd:c25:dd0:ec00:9f9
2512c19:dd:d9:dd:c25:dd0:ec00:9fa/1282c19:dd:d9:dd:c25:dd0:ec00:9fa
2522c19:dd:d9:dd:c25:dd0:ec00:9fb/1282c19:dd:d9:dd:c25:dd0:ec00:9fb
2532c19:dd:d9:dd:c25:dd0:ec00:9fc/1282c19:dd:d9:dd:c25:dd0:ec00:9fc
2542c19:dd:d9:dd:c25:dd0:ec00:9fd/1282c19:dd:d9:dd:c25:dd0:ec00:9fd
2552c19:dd:d9:dd:c25:dd0:ec00:9fe/1282c19:dd:d9:dd:c25:dd0:ec00:9fe
2562c19:dd:d9:dd:c25:dd0:ec00:9ff/1282c19:dd:d9:dd:c25:dd0:ec00:9ff

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.