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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:6900/120
First address
2c19:dd:d9:dd:c25:c25:94de:6900
Last address
2c19:dd:d9:dd:c25:c25:94de:69ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:6900
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.6.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:6900/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:6900/1282c19:dd:d9:dd:c25:c25:94de:6900
22c19:dd:d9:dd:c25:c25:94de:6901/1282c19:dd:d9:dd:c25:c25:94de:6901
32c19:dd:d9:dd:c25:c25:94de:6902/1282c19:dd:d9:dd:c25:c25:94de:6902
42c19:dd:d9:dd:c25:c25:94de:6903/1282c19:dd:d9:dd:c25:c25:94de:6903
52c19:dd:d9:dd:c25:c25:94de:6904/1282c19:dd:d9:dd:c25:c25:94de:6904
62c19:dd:d9:dd:c25:c25:94de:6905/1282c19:dd:d9:dd:c25:c25:94de:6905
72c19:dd:d9:dd:c25:c25:94de:6906/1282c19:dd:d9:dd:c25:c25:94de:6906
82c19:dd:d9:dd:c25:c25:94de:6907/1282c19:dd:d9:dd:c25:c25:94de:6907
92c19:dd:d9:dd:c25:c25:94de:6908/1282c19:dd:d9:dd:c25:c25:94de:6908
102c19:dd:d9:dd:c25:c25:94de:6909/1282c19:dd:d9:dd:c25:c25:94de:6909
112c19:dd:d9:dd:c25:c25:94de:690a/1282c19:dd:d9:dd:c25:c25:94de:690a
122c19:dd:d9:dd:c25:c25:94de:690b/1282c19:dd:d9:dd:c25:c25:94de:690b
132c19:dd:d9:dd:c25:c25:94de:690c/1282c19:dd:d9:dd:c25:c25:94de:690c
142c19:dd:d9:dd:c25:c25:94de:690d/1282c19:dd:d9:dd:c25:c25:94de:690d
152c19:dd:d9:dd:c25:c25:94de:690e/1282c19:dd:d9:dd:c25:c25:94de:690e
162c19:dd:d9:dd:c25:c25:94de:690f/1282c19:dd:d9:dd:c25:c25:94de:690f
172c19:dd:d9:dd:c25:c25:94de:6910/1282c19:dd:d9:dd:c25:c25:94de:6910
182c19:dd:d9:dd:c25:c25:94de:6911/1282c19:dd:d9:dd:c25:c25:94de:6911
192c19:dd:d9:dd:c25:c25:94de:6912/1282c19:dd:d9:dd:c25:c25:94de:6912
202c19:dd:d9:dd:c25:c25:94de:6913/1282c19:dd:d9:dd:c25:c25:94de:6913
212c19:dd:d9:dd:c25:c25:94de:6914/1282c19:dd:d9:dd:c25:c25:94de:6914
222c19:dd:d9:dd:c25:c25:94de:6915/1282c19:dd:d9:dd:c25:c25:94de:6915
232c19:dd:d9:dd:c25:c25:94de:6916/1282c19:dd:d9:dd:c25:c25:94de:6916
242c19:dd:d9:dd:c25:c25:94de:6917/1282c19:dd:d9:dd:c25:c25:94de:6917
252c19:dd:d9:dd:c25:c25:94de:6918/1282c19:dd:d9:dd:c25:c25:94de:6918
262c19:dd:d9:dd:c25:c25:94de:6919/1282c19:dd:d9:dd:c25:c25:94de:6919
272c19:dd:d9:dd:c25:c25:94de:691a/1282c19:dd:d9:dd:c25:c25:94de:691a
282c19:dd:d9:dd:c25:c25:94de:691b/1282c19:dd:d9:dd:c25:c25:94de:691b
292c19:dd:d9:dd:c25:c25:94de:691c/1282c19:dd:d9:dd:c25:c25:94de:691c
302c19:dd:d9:dd:c25:c25:94de:691d/1282c19:dd:d9:dd:c25:c25:94de:691d
312c19:dd:d9:dd:c25:c25:94de:691e/1282c19:dd:d9:dd:c25:c25:94de:691e
322c19:dd:d9:dd:c25:c25:94de:691f/1282c19:dd:d9:dd:c25:c25:94de:691f
332c19:dd:d9:dd:c25:c25:94de:6920/1282c19:dd:d9:dd:c25:c25:94de:6920
342c19:dd:d9:dd:c25:c25:94de:6921/1282c19:dd:d9:dd:c25:c25:94de:6921
352c19:dd:d9:dd:c25:c25:94de:6922/1282c19:dd:d9:dd:c25:c25:94de:6922
362c19:dd:d9:dd:c25:c25:94de:6923/1282c19:dd:d9:dd:c25:c25:94de:6923
372c19:dd:d9:dd:c25:c25:94de:6924/1282c19:dd:d9:dd:c25:c25:94de:6924
382c19:dd:d9:dd:c25:c25:94de:6925/1282c19:dd:d9:dd:c25:c25:94de:6925
392c19:dd:d9:dd:c25:c25:94de:6926/1282c19:dd:d9:dd:c25:c25:94de:6926
402c19:dd:d9:dd:c25:c25:94de:6927/1282c19:dd:d9:dd:c25:c25:94de:6927
412c19:dd:d9:dd:c25:c25:94de:6928/1282c19:dd:d9:dd:c25:c25:94de:6928
422c19:dd:d9:dd:c25:c25:94de:6929/1282c19:dd:d9:dd:c25:c25:94de:6929
432c19:dd:d9:dd:c25:c25:94de:692a/1282c19:dd:d9:dd:c25:c25:94de:692a
442c19:dd:d9:dd:c25:c25:94de:692b/1282c19:dd:d9:dd:c25:c25:94de:692b
452c19:dd:d9:dd:c25:c25:94de:692c/1282c19:dd:d9:dd:c25:c25:94de:692c
462c19:dd:d9:dd:c25:c25:94de:692d/1282c19:dd:d9:dd:c25:c25:94de:692d
472c19:dd:d9:dd:c25:c25:94de:692e/1282c19:dd:d9:dd:c25:c25:94de:692e
482c19:dd:d9:dd:c25:c25:94de:692f/1282c19:dd:d9:dd:c25:c25:94de:692f
492c19:dd:d9:dd:c25:c25:94de:6930/1282c19:dd:d9:dd:c25:c25:94de:6930
502c19:dd:d9:dd:c25:c25:94de:6931/1282c19:dd:d9:dd:c25:c25:94de:6931
512c19:dd:d9:dd:c25:c25:94de:6932/1282c19:dd:d9:dd:c25:c25:94de:6932
522c19:dd:d9:dd:c25:c25:94de:6933/1282c19:dd:d9:dd:c25:c25:94de:6933
532c19:dd:d9:dd:c25:c25:94de:6934/1282c19:dd:d9:dd:c25:c25:94de:6934
542c19:dd:d9:dd:c25:c25:94de:6935/1282c19:dd:d9:dd:c25:c25:94de:6935
552c19:dd:d9:dd:c25:c25:94de:6936/1282c19:dd:d9:dd:c25:c25:94de:6936
562c19:dd:d9:dd:c25:c25:94de:6937/1282c19:dd:d9:dd:c25:c25:94de:6937
572c19:dd:d9:dd:c25:c25:94de:6938/1282c19:dd:d9:dd:c25:c25:94de:6938
582c19:dd:d9:dd:c25:c25:94de:6939/1282c19:dd:d9:dd:c25:c25:94de:6939
592c19:dd:d9:dd:c25:c25:94de:693a/1282c19:dd:d9:dd:c25:c25:94de:693a
602c19:dd:d9:dd:c25:c25:94de:693b/1282c19:dd:d9:dd:c25:c25:94de:693b
612c19:dd:d9:dd:c25:c25:94de:693c/1282c19:dd:d9:dd:c25:c25:94de:693c
622c19:dd:d9:dd:c25:c25:94de:693d/1282c19:dd:d9:dd:c25:c25:94de:693d
632c19:dd:d9:dd:c25:c25:94de:693e/1282c19:dd:d9:dd:c25:c25:94de:693e
642c19:dd:d9:dd:c25:c25:94de:693f/1282c19:dd:d9:dd:c25:c25:94de:693f
652c19:dd:d9:dd:c25:c25:94de:6940/1282c19:dd:d9:dd:c25:c25:94de:6940
662c19:dd:d9:dd:c25:c25:94de:6941/1282c19:dd:d9:dd:c25:c25:94de:6941
672c19:dd:d9:dd:c25:c25:94de:6942/1282c19:dd:d9:dd:c25:c25:94de:6942
682c19:dd:d9:dd:c25:c25:94de:6943/1282c19:dd:d9:dd:c25:c25:94de:6943
692c19:dd:d9:dd:c25:c25:94de:6944/1282c19:dd:d9:dd:c25:c25:94de:6944
702c19:dd:d9:dd:c25:c25:94de:6945/1282c19:dd:d9:dd:c25:c25:94de:6945
712c19:dd:d9:dd:c25:c25:94de:6946/1282c19:dd:d9:dd:c25:c25:94de:6946
722c19:dd:d9:dd:c25:c25:94de:6947/1282c19:dd:d9:dd:c25:c25:94de:6947
732c19:dd:d9:dd:c25:c25:94de:6948/1282c19:dd:d9:dd:c25:c25:94de:6948
742c19:dd:d9:dd:c25:c25:94de:6949/1282c19:dd:d9:dd:c25:c25:94de:6949
752c19:dd:d9:dd:c25:c25:94de:694a/1282c19:dd:d9:dd:c25:c25:94de:694a
762c19:dd:d9:dd:c25:c25:94de:694b/1282c19:dd:d9:dd:c25:c25:94de:694b
772c19:dd:d9:dd:c25:c25:94de:694c/1282c19:dd:d9:dd:c25:c25:94de:694c
782c19:dd:d9:dd:c25:c25:94de:694d/1282c19:dd:d9:dd:c25:c25:94de:694d
792c19:dd:d9:dd:c25:c25:94de:694e/1282c19:dd:d9:dd:c25:c25:94de:694e
802c19:dd:d9:dd:c25:c25:94de:694f/1282c19:dd:d9:dd:c25:c25:94de:694f
812c19:dd:d9:dd:c25:c25:94de:6950/1282c19:dd:d9:dd:c25:c25:94de:6950
822c19:dd:d9:dd:c25:c25:94de:6951/1282c19:dd:d9:dd:c25:c25:94de:6951
832c19:dd:d9:dd:c25:c25:94de:6952/1282c19:dd:d9:dd:c25:c25:94de:6952
842c19:dd:d9:dd:c25:c25:94de:6953/1282c19:dd:d9:dd:c25:c25:94de:6953
852c19:dd:d9:dd:c25:c25:94de:6954/1282c19:dd:d9:dd:c25:c25:94de:6954
862c19:dd:d9:dd:c25:c25:94de:6955/1282c19:dd:d9:dd:c25:c25:94de:6955
872c19:dd:d9:dd:c25:c25:94de:6956/1282c19:dd:d9:dd:c25:c25:94de:6956
882c19:dd:d9:dd:c25:c25:94de:6957/1282c19:dd:d9:dd:c25:c25:94de:6957
892c19:dd:d9:dd:c25:c25:94de:6958/1282c19:dd:d9:dd:c25:c25:94de:6958
902c19:dd:d9:dd:c25:c25:94de:6959/1282c19:dd:d9:dd:c25:c25:94de:6959
912c19:dd:d9:dd:c25:c25:94de:695a/1282c19:dd:d9:dd:c25:c25:94de:695a
922c19:dd:d9:dd:c25:c25:94de:695b/1282c19:dd:d9:dd:c25:c25:94de:695b
932c19:dd:d9:dd:c25:c25:94de:695c/1282c19:dd:d9:dd:c25:c25:94de:695c
942c19:dd:d9:dd:c25:c25:94de:695d/1282c19:dd:d9:dd:c25:c25:94de:695d
952c19:dd:d9:dd:c25:c25:94de:695e/1282c19:dd:d9:dd:c25:c25:94de:695e
962c19:dd:d9:dd:c25:c25:94de:695f/1282c19:dd:d9:dd:c25:c25:94de:695f
972c19:dd:d9:dd:c25:c25:94de:6960/1282c19:dd:d9:dd:c25:c25:94de:6960
982c19:dd:d9:dd:c25:c25:94de:6961/1282c19:dd:d9:dd:c25:c25:94de:6961
992c19:dd:d9:dd:c25:c25:94de:6962/1282c19:dd:d9:dd:c25:c25:94de:6962
1002c19:dd:d9:dd:c25:c25:94de:6963/1282c19:dd:d9:dd:c25:c25:94de:6963
1012c19:dd:d9:dd:c25:c25:94de:6964/1282c19:dd:d9:dd:c25:c25:94de:6964
1022c19:dd:d9:dd:c25:c25:94de:6965/1282c19:dd:d9:dd:c25:c25:94de:6965
1032c19:dd:d9:dd:c25:c25:94de:6966/1282c19:dd:d9:dd:c25:c25:94de:6966
1042c19:dd:d9:dd:c25:c25:94de:6967/1282c19:dd:d9:dd:c25:c25:94de:6967
1052c19:dd:d9:dd:c25:c25:94de:6968/1282c19:dd:d9:dd:c25:c25:94de:6968
1062c19:dd:d9:dd:c25:c25:94de:6969/1282c19:dd:d9:dd:c25:c25:94de:6969
1072c19:dd:d9:dd:c25:c25:94de:696a/1282c19:dd:d9:dd:c25:c25:94de:696a
1082c19:dd:d9:dd:c25:c25:94de:696b/1282c19:dd:d9:dd:c25:c25:94de:696b
1092c19:dd:d9:dd:c25:c25:94de:696c/1282c19:dd:d9:dd:c25:c25:94de:696c
1102c19:dd:d9:dd:c25:c25:94de:696d/1282c19:dd:d9:dd:c25:c25:94de:696d
1112c19:dd:d9:dd:c25:c25:94de:696e/1282c19:dd:d9:dd:c25:c25:94de:696e
1122c19:dd:d9:dd:c25:c25:94de:696f/1282c19:dd:d9:dd:c25:c25:94de:696f
1132c19:dd:d9:dd:c25:c25:94de:6970/1282c19:dd:d9:dd:c25:c25:94de:6970
1142c19:dd:d9:dd:c25:c25:94de:6971/1282c19:dd:d9:dd:c25:c25:94de:6971
1152c19:dd:d9:dd:c25:c25:94de:6972/1282c19:dd:d9:dd:c25:c25:94de:6972
1162c19:dd:d9:dd:c25:c25:94de:6973/1282c19:dd:d9:dd:c25:c25:94de:6973
1172c19:dd:d9:dd:c25:c25:94de:6974/1282c19:dd:d9:dd:c25:c25:94de:6974
1182c19:dd:d9:dd:c25:c25:94de:6975/1282c19:dd:d9:dd:c25:c25:94de:6975
1192c19:dd:d9:dd:c25:c25:94de:6976/1282c19:dd:d9:dd:c25:c25:94de:6976
1202c19:dd:d9:dd:c25:c25:94de:6977/1282c19:dd:d9:dd:c25:c25:94de:6977
1212c19:dd:d9:dd:c25:c25:94de:6978/1282c19:dd:d9:dd:c25:c25:94de:6978
1222c19:dd:d9:dd:c25:c25:94de:6979/1282c19:dd:d9:dd:c25:c25:94de:6979
1232c19:dd:d9:dd:c25:c25:94de:697a/1282c19:dd:d9:dd:c25:c25:94de:697a
1242c19:dd:d9:dd:c25:c25:94de:697b/1282c19:dd:d9:dd:c25:c25:94de:697b
1252c19:dd:d9:dd:c25:c25:94de:697c/1282c19:dd:d9:dd:c25:c25:94de:697c
1262c19:dd:d9:dd:c25:c25:94de:697d/1282c19:dd:d9:dd:c25:c25:94de:697d
1272c19:dd:d9:dd:c25:c25:94de:697e/1282c19:dd:d9:dd:c25:c25:94de:697e
1282c19:dd:d9:dd:c25:c25:94de:697f/1282c19:dd:d9:dd:c25:c25:94de:697f
1292c19:dd:d9:dd:c25:c25:94de:6980/1282c19:dd:d9:dd:c25:c25:94de:6980
1302c19:dd:d9:dd:c25:c25:94de:6981/1282c19:dd:d9:dd:c25:c25:94de:6981
1312c19:dd:d9:dd:c25:c25:94de:6982/1282c19:dd:d9:dd:c25:c25:94de:6982
1322c19:dd:d9:dd:c25:c25:94de:6983/1282c19:dd:d9:dd:c25:c25:94de:6983
1332c19:dd:d9:dd:c25:c25:94de:6984/1282c19:dd:d9:dd:c25:c25:94de:6984
1342c19:dd:d9:dd:c25:c25:94de:6985/1282c19:dd:d9:dd:c25:c25:94de:6985
1352c19:dd:d9:dd:c25:c25:94de:6986/1282c19:dd:d9:dd:c25:c25:94de:6986
1362c19:dd:d9:dd:c25:c25:94de:6987/1282c19:dd:d9:dd:c25:c25:94de:6987
1372c19:dd:d9:dd:c25:c25:94de:6988/1282c19:dd:d9:dd:c25:c25:94de:6988
1382c19:dd:d9:dd:c25:c25:94de:6989/1282c19:dd:d9:dd:c25:c25:94de:6989
1392c19:dd:d9:dd:c25:c25:94de:698a/1282c19:dd:d9:dd:c25:c25:94de:698a
1402c19:dd:d9:dd:c25:c25:94de:698b/1282c19:dd:d9:dd:c25:c25:94de:698b
1412c19:dd:d9:dd:c25:c25:94de:698c/1282c19:dd:d9:dd:c25:c25:94de:698c
1422c19:dd:d9:dd:c25:c25:94de:698d/1282c19:dd:d9:dd:c25:c25:94de:698d
1432c19:dd:d9:dd:c25:c25:94de:698e/1282c19:dd:d9:dd:c25:c25:94de:698e
1442c19:dd:d9:dd:c25:c25:94de:698f/1282c19:dd:d9:dd:c25:c25:94de:698f
1452c19:dd:d9:dd:c25:c25:94de:6990/1282c19:dd:d9:dd:c25:c25:94de:6990
1462c19:dd:d9:dd:c25:c25:94de:6991/1282c19:dd:d9:dd:c25:c25:94de:6991
1472c19:dd:d9:dd:c25:c25:94de:6992/1282c19:dd:d9:dd:c25:c25:94de:6992
1482c19:dd:d9:dd:c25:c25:94de:6993/1282c19:dd:d9:dd:c25:c25:94de:6993
1492c19:dd:d9:dd:c25:c25:94de:6994/1282c19:dd:d9:dd:c25:c25:94de:6994
1502c19:dd:d9:dd:c25:c25:94de:6995/1282c19:dd:d9:dd:c25:c25:94de:6995
1512c19:dd:d9:dd:c25:c25:94de:6996/1282c19:dd:d9:dd:c25:c25:94de:6996
1522c19:dd:d9:dd:c25:c25:94de:6997/1282c19:dd:d9:dd:c25:c25:94de:6997
1532c19:dd:d9:dd:c25:c25:94de:6998/1282c19:dd:d9:dd:c25:c25:94de:6998
1542c19:dd:d9:dd:c25:c25:94de:6999/1282c19:dd:d9:dd:c25:c25:94de:6999
1552c19:dd:d9:dd:c25:c25:94de:699a/1282c19:dd:d9:dd:c25:c25:94de:699a
1562c19:dd:d9:dd:c25:c25:94de:699b/1282c19:dd:d9:dd:c25:c25:94de:699b
1572c19:dd:d9:dd:c25:c25:94de:699c/1282c19:dd:d9:dd:c25:c25:94de:699c
1582c19:dd:d9:dd:c25:c25:94de:699d/1282c19:dd:d9:dd:c25:c25:94de:699d
1592c19:dd:d9:dd:c25:c25:94de:699e/1282c19:dd:d9:dd:c25:c25:94de:699e
1602c19:dd:d9:dd:c25:c25:94de:699f/1282c19:dd:d9:dd:c25:c25:94de:699f
1612c19:dd:d9:dd:c25:c25:94de:69a0/1282c19:dd:d9:dd:c25:c25:94de:69a0
1622c19:dd:d9:dd:c25:c25:94de:69a1/1282c19:dd:d9:dd:c25:c25:94de:69a1
1632c19:dd:d9:dd:c25:c25:94de:69a2/1282c19:dd:d9:dd:c25:c25:94de:69a2
1642c19:dd:d9:dd:c25:c25:94de:69a3/1282c19:dd:d9:dd:c25:c25:94de:69a3
1652c19:dd:d9:dd:c25:c25:94de:69a4/1282c19:dd:d9:dd:c25:c25:94de:69a4
1662c19:dd:d9:dd:c25:c25:94de:69a5/1282c19:dd:d9:dd:c25:c25:94de:69a5
1672c19:dd:d9:dd:c25:c25:94de:69a6/1282c19:dd:d9:dd:c25:c25:94de:69a6
1682c19:dd:d9:dd:c25:c25:94de:69a7/1282c19:dd:d9:dd:c25:c25:94de:69a7
1692c19:dd:d9:dd:c25:c25:94de:69a8/1282c19:dd:d9:dd:c25:c25:94de:69a8
1702c19:dd:d9:dd:c25:c25:94de:69a9/1282c19:dd:d9:dd:c25:c25:94de:69a9
1712c19:dd:d9:dd:c25:c25:94de:69aa/1282c19:dd:d9:dd:c25:c25:94de:69aa
1722c19:dd:d9:dd:c25:c25:94de:69ab/1282c19:dd:d9:dd:c25:c25:94de:69ab
1732c19:dd:d9:dd:c25:c25:94de:69ac/1282c19:dd:d9:dd:c25:c25:94de:69ac
1742c19:dd:d9:dd:c25:c25:94de:69ad/1282c19:dd:d9:dd:c25:c25:94de:69ad
1752c19:dd:d9:dd:c25:c25:94de:69ae/1282c19:dd:d9:dd:c25:c25:94de:69ae
1762c19:dd:d9:dd:c25:c25:94de:69af/1282c19:dd:d9:dd:c25:c25:94de:69af
1772c19:dd:d9:dd:c25:c25:94de:69b0/1282c19:dd:d9:dd:c25:c25:94de:69b0
1782c19:dd:d9:dd:c25:c25:94de:69b1/1282c19:dd:d9:dd:c25:c25:94de:69b1
1792c19:dd:d9:dd:c25:c25:94de:69b2/1282c19:dd:d9:dd:c25:c25:94de:69b2
1802c19:dd:d9:dd:c25:c25:94de:69b3/1282c19:dd:d9:dd:c25:c25:94de:69b3
1812c19:dd:d9:dd:c25:c25:94de:69b4/1282c19:dd:d9:dd:c25:c25:94de:69b4
1822c19:dd:d9:dd:c25:c25:94de:69b5/1282c19:dd:d9:dd:c25:c25:94de:69b5
1832c19:dd:d9:dd:c25:c25:94de:69b6/1282c19:dd:d9:dd:c25:c25:94de:69b6
1842c19:dd:d9:dd:c25:c25:94de:69b7/1282c19:dd:d9:dd:c25:c25:94de:69b7
1852c19:dd:d9:dd:c25:c25:94de:69b8/1282c19:dd:d9:dd:c25:c25:94de:69b8
1862c19:dd:d9:dd:c25:c25:94de:69b9/1282c19:dd:d9:dd:c25:c25:94de:69b9
1872c19:dd:d9:dd:c25:c25:94de:69ba/1282c19:dd:d9:dd:c25:c25:94de:69ba
1882c19:dd:d9:dd:c25:c25:94de:69bb/1282c19:dd:d9:dd:c25:c25:94de:69bb
1892c19:dd:d9:dd:c25:c25:94de:69bc/1282c19:dd:d9:dd:c25:c25:94de:69bc
1902c19:dd:d9:dd:c25:c25:94de:69bd/1282c19:dd:d9:dd:c25:c25:94de:69bd
1912c19:dd:d9:dd:c25:c25:94de:69be/1282c19:dd:d9:dd:c25:c25:94de:69be
1922c19:dd:d9:dd:c25:c25:94de:69bf/1282c19:dd:d9:dd:c25:c25:94de:69bf
1932c19:dd:d9:dd:c25:c25:94de:69c0/1282c19:dd:d9:dd:c25:c25:94de:69c0
1942c19:dd:d9:dd:c25:c25:94de:69c1/1282c19:dd:d9:dd:c25:c25:94de:69c1
1952c19:dd:d9:dd:c25:c25:94de:69c2/1282c19:dd:d9:dd:c25:c25:94de:69c2
1962c19:dd:d9:dd:c25:c25:94de:69c3/1282c19:dd:d9:dd:c25:c25:94de:69c3
1972c19:dd:d9:dd:c25:c25:94de:69c4/1282c19:dd:d9:dd:c25:c25:94de:69c4
1982c19:dd:d9:dd:c25:c25:94de:69c5/1282c19:dd:d9:dd:c25:c25:94de:69c5
1992c19:dd:d9:dd:c25:c25:94de:69c6/1282c19:dd:d9:dd:c25:c25:94de:69c6
2002c19:dd:d9:dd:c25:c25:94de:69c7/1282c19:dd:d9:dd:c25:c25:94de:69c7
2012c19:dd:d9:dd:c25:c25:94de:69c8/1282c19:dd:d9:dd:c25:c25:94de:69c8
2022c19:dd:d9:dd:c25:c25:94de:69c9/1282c19:dd:d9:dd:c25:c25:94de:69c9
2032c19:dd:d9:dd:c25:c25:94de:69ca/1282c19:dd:d9:dd:c25:c25:94de:69ca
2042c19:dd:d9:dd:c25:c25:94de:69cb/1282c19:dd:d9:dd:c25:c25:94de:69cb
2052c19:dd:d9:dd:c25:c25:94de:69cc/1282c19:dd:d9:dd:c25:c25:94de:69cc
2062c19:dd:d9:dd:c25:c25:94de:69cd/1282c19:dd:d9:dd:c25:c25:94de:69cd
2072c19:dd:d9:dd:c25:c25:94de:69ce/1282c19:dd:d9:dd:c25:c25:94de:69ce
2082c19:dd:d9:dd:c25:c25:94de:69cf/1282c19:dd:d9:dd:c25:c25:94de:69cf
2092c19:dd:d9:dd:c25:c25:94de:69d0/1282c19:dd:d9:dd:c25:c25:94de:69d0
2102c19:dd:d9:dd:c25:c25:94de:69d1/1282c19:dd:d9:dd:c25:c25:94de:69d1
2112c19:dd:d9:dd:c25:c25:94de:69d2/1282c19:dd:d9:dd:c25:c25:94de:69d2
2122c19:dd:d9:dd:c25:c25:94de:69d3/1282c19:dd:d9:dd:c25:c25:94de:69d3
2132c19:dd:d9:dd:c25:c25:94de:69d4/1282c19:dd:d9:dd:c25:c25:94de:69d4
2142c19:dd:d9:dd:c25:c25:94de:69d5/1282c19:dd:d9:dd:c25:c25:94de:69d5
2152c19:dd:d9:dd:c25:c25:94de:69d6/1282c19:dd:d9:dd:c25:c25:94de:69d6
2162c19:dd:d9:dd:c25:c25:94de:69d7/1282c19:dd:d9:dd:c25:c25:94de:69d7
2172c19:dd:d9:dd:c25:c25:94de:69d8/1282c19:dd:d9:dd:c25:c25:94de:69d8
2182c19:dd:d9:dd:c25:c25:94de:69d9/1282c19:dd:d9:dd:c25:c25:94de:69d9
2192c19:dd:d9:dd:c25:c25:94de:69da/1282c19:dd:d9:dd:c25:c25:94de:69da
2202c19:dd:d9:dd:c25:c25:94de:69db/1282c19:dd:d9:dd:c25:c25:94de:69db
2212c19:dd:d9:dd:c25:c25:94de:69dc/1282c19:dd:d9:dd:c25:c25:94de:69dc
2222c19:dd:d9:dd:c25:c25:94de:69dd/1282c19:dd:d9:dd:c25:c25:94de:69dd
2232c19:dd:d9:dd:c25:c25:94de:69de/1282c19:dd:d9:dd:c25:c25:94de:69de
2242c19:dd:d9:dd:c25:c25:94de:69df/1282c19:dd:d9:dd:c25:c25:94de:69df
2252c19:dd:d9:dd:c25:c25:94de:69e0/1282c19:dd:d9:dd:c25:c25:94de:69e0
2262c19:dd:d9:dd:c25:c25:94de:69e1/1282c19:dd:d9:dd:c25:c25:94de:69e1
2272c19:dd:d9:dd:c25:c25:94de:69e2/1282c19:dd:d9:dd:c25:c25:94de:69e2
2282c19:dd:d9:dd:c25:c25:94de:69e3/1282c19:dd:d9:dd:c25:c25:94de:69e3
2292c19:dd:d9:dd:c25:c25:94de:69e4/1282c19:dd:d9:dd:c25:c25:94de:69e4
2302c19:dd:d9:dd:c25:c25:94de:69e5/1282c19:dd:d9:dd:c25:c25:94de:69e5
2312c19:dd:d9:dd:c25:c25:94de:69e6/1282c19:dd:d9:dd:c25:c25:94de:69e6
2322c19:dd:d9:dd:c25:c25:94de:69e7/1282c19:dd:d9:dd:c25:c25:94de:69e7
2332c19:dd:d9:dd:c25:c25:94de:69e8/1282c19:dd:d9:dd:c25:c25:94de:69e8
2342c19:dd:d9:dd:c25:c25:94de:69e9/1282c19:dd:d9:dd:c25:c25:94de:69e9
2352c19:dd:d9:dd:c25:c25:94de:69ea/1282c19:dd:d9:dd:c25:c25:94de:69ea
2362c19:dd:d9:dd:c25:c25:94de:69eb/1282c19:dd:d9:dd:c25:c25:94de:69eb
2372c19:dd:d9:dd:c25:c25:94de:69ec/1282c19:dd:d9:dd:c25:c25:94de:69ec
2382c19:dd:d9:dd:c25:c25:94de:69ed/1282c19:dd:d9:dd:c25:c25:94de:69ed
2392c19:dd:d9:dd:c25:c25:94de:69ee/1282c19:dd:d9:dd:c25:c25:94de:69ee
2402c19:dd:d9:dd:c25:c25:94de:69ef/1282c19:dd:d9:dd:c25:c25:94de:69ef
2412c19:dd:d9:dd:c25:c25:94de:69f0/1282c19:dd:d9:dd:c25:c25:94de:69f0
2422c19:dd:d9:dd:c25:c25:94de:69f1/1282c19:dd:d9:dd:c25:c25:94de:69f1
2432c19:dd:d9:dd:c25:c25:94de:69f2/1282c19:dd:d9:dd:c25:c25:94de:69f2
2442c19:dd:d9:dd:c25:c25:94de:69f3/1282c19:dd:d9:dd:c25:c25:94de:69f3
2452c19:dd:d9:dd:c25:c25:94de:69f4/1282c19:dd:d9:dd:c25:c25:94de:69f4
2462c19:dd:d9:dd:c25:c25:94de:69f5/1282c19:dd:d9:dd:c25:c25:94de:69f5
2472c19:dd:d9:dd:c25:c25:94de:69f6/1282c19:dd:d9:dd:c25:c25:94de:69f6
2482c19:dd:d9:dd:c25:c25:94de:69f7/1282c19:dd:d9:dd:c25:c25:94de:69f7
2492c19:dd:d9:dd:c25:c25:94de:69f8/1282c19:dd:d9:dd:c25:c25:94de:69f8
2502c19:dd:d9:dd:c25:c25:94de:69f9/1282c19:dd:d9:dd:c25:c25:94de:69f9
2512c19:dd:d9:dd:c25:c25:94de:69fa/1282c19:dd:d9:dd:c25:c25:94de:69fa
2522c19:dd:d9:dd:c25:c25:94de:69fb/1282c19:dd:d9:dd:c25:c25:94de:69fb
2532c19:dd:d9:dd:c25:c25:94de:69fc/1282c19:dd:d9:dd:c25:c25:94de:69fc
2542c19:dd:d9:dd:c25:c25:94de:69fd/1282c19:dd:d9:dd:c25:c25:94de:69fd
2552c19:dd:d9:dd:c25:c25:94de:69fe/1282c19:dd:d9:dd:c25:c25:94de:69fe
2562c19:dd:d9:dd:c25:c25:94de:69ff/1282c19:dd:d9:dd:c25:c25:94de:69ff

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.