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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:dd0:ec00:c25:c25:dd4e:f800/120
First address
2c19:dd:dd0:ec00:c25:c25:dd4e:f800
Last address
2c19:dd:dd0:ec00:c25:c25:dd4e:f8ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0dd0:ec00:0c25:0c25:dd4e:f800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.f.e.4.d.d.5.2.c.0.5.2.c.0.0.0.c.e.0.d.d.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:dd0:ec00:c25:c25:dd4e:f800/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:dd0:ec00:c25:c25:dd4e:f800/1282c19:dd:dd0:ec00:c25:c25:dd4e:f800
22c19:dd:dd0:ec00:c25:c25:dd4e:f801/1282c19:dd:dd0:ec00:c25:c25:dd4e:f801
32c19:dd:dd0:ec00:c25:c25:dd4e:f802/1282c19:dd:dd0:ec00:c25:c25:dd4e:f802
42c19:dd:dd0:ec00:c25:c25:dd4e:f803/1282c19:dd:dd0:ec00:c25:c25:dd4e:f803
52c19:dd:dd0:ec00:c25:c25:dd4e:f804/1282c19:dd:dd0:ec00:c25:c25:dd4e:f804
62c19:dd:dd0:ec00:c25:c25:dd4e:f805/1282c19:dd:dd0:ec00:c25:c25:dd4e:f805
72c19:dd:dd0:ec00:c25:c25:dd4e:f806/1282c19:dd:dd0:ec00:c25:c25:dd4e:f806
82c19:dd:dd0:ec00:c25:c25:dd4e:f807/1282c19:dd:dd0:ec00:c25:c25:dd4e:f807
92c19:dd:dd0:ec00:c25:c25:dd4e:f808/1282c19:dd:dd0:ec00:c25:c25:dd4e:f808
102c19:dd:dd0:ec00:c25:c25:dd4e:f809/1282c19:dd:dd0:ec00:c25:c25:dd4e:f809
112c19:dd:dd0:ec00:c25:c25:dd4e:f80a/1282c19:dd:dd0:ec00:c25:c25:dd4e:f80a
122c19:dd:dd0:ec00:c25:c25:dd4e:f80b/1282c19:dd:dd0:ec00:c25:c25:dd4e:f80b
132c19:dd:dd0:ec00:c25:c25:dd4e:f80c/1282c19:dd:dd0:ec00:c25:c25:dd4e:f80c
142c19:dd:dd0:ec00:c25:c25:dd4e:f80d/1282c19:dd:dd0:ec00:c25:c25:dd4e:f80d
152c19:dd:dd0:ec00:c25:c25:dd4e:f80e/1282c19:dd:dd0:ec00:c25:c25:dd4e:f80e
162c19:dd:dd0:ec00:c25:c25:dd4e:f80f/1282c19:dd:dd0:ec00:c25:c25:dd4e:f80f
172c19:dd:dd0:ec00:c25:c25:dd4e:f810/1282c19:dd:dd0:ec00:c25:c25:dd4e:f810
182c19:dd:dd0:ec00:c25:c25:dd4e:f811/1282c19:dd:dd0:ec00:c25:c25:dd4e:f811
192c19:dd:dd0:ec00:c25:c25:dd4e:f812/1282c19:dd:dd0:ec00:c25:c25:dd4e:f812
202c19:dd:dd0:ec00:c25:c25:dd4e:f813/1282c19:dd:dd0:ec00:c25:c25:dd4e:f813
212c19:dd:dd0:ec00:c25:c25:dd4e:f814/1282c19:dd:dd0:ec00:c25:c25:dd4e:f814
222c19:dd:dd0:ec00:c25:c25:dd4e:f815/1282c19:dd:dd0:ec00:c25:c25:dd4e:f815
232c19:dd:dd0:ec00:c25:c25:dd4e:f816/1282c19:dd:dd0:ec00:c25:c25:dd4e:f816
242c19:dd:dd0:ec00:c25:c25:dd4e:f817/1282c19:dd:dd0:ec00:c25:c25:dd4e:f817
252c19:dd:dd0:ec00:c25:c25:dd4e:f818/1282c19:dd:dd0:ec00:c25:c25:dd4e:f818
262c19:dd:dd0:ec00:c25:c25:dd4e:f819/1282c19:dd:dd0:ec00:c25:c25:dd4e:f819
272c19:dd:dd0:ec00:c25:c25:dd4e:f81a/1282c19:dd:dd0:ec00:c25:c25:dd4e:f81a
282c19:dd:dd0:ec00:c25:c25:dd4e:f81b/1282c19:dd:dd0:ec00:c25:c25:dd4e:f81b
292c19:dd:dd0:ec00:c25:c25:dd4e:f81c/1282c19:dd:dd0:ec00:c25:c25:dd4e:f81c
302c19:dd:dd0:ec00:c25:c25:dd4e:f81d/1282c19:dd:dd0:ec00:c25:c25:dd4e:f81d
312c19:dd:dd0:ec00:c25:c25:dd4e:f81e/1282c19:dd:dd0:ec00:c25:c25:dd4e:f81e
322c19:dd:dd0:ec00:c25:c25:dd4e:f81f/1282c19:dd:dd0:ec00:c25:c25:dd4e:f81f
332c19:dd:dd0:ec00:c25:c25:dd4e:f820/1282c19:dd:dd0:ec00:c25:c25:dd4e:f820
342c19:dd:dd0:ec00:c25:c25:dd4e:f821/1282c19:dd:dd0:ec00:c25:c25:dd4e:f821
352c19:dd:dd0:ec00:c25:c25:dd4e:f822/1282c19:dd:dd0:ec00:c25:c25:dd4e:f822
362c19:dd:dd0:ec00:c25:c25:dd4e:f823/1282c19:dd:dd0:ec00:c25:c25:dd4e:f823
372c19:dd:dd0:ec00:c25:c25:dd4e:f824/1282c19:dd:dd0:ec00:c25:c25:dd4e:f824
382c19:dd:dd0:ec00:c25:c25:dd4e:f825/1282c19:dd:dd0:ec00:c25:c25:dd4e:f825
392c19:dd:dd0:ec00:c25:c25:dd4e:f826/1282c19:dd:dd0:ec00:c25:c25:dd4e:f826
402c19:dd:dd0:ec00:c25:c25:dd4e:f827/1282c19:dd:dd0:ec00:c25:c25:dd4e:f827
412c19:dd:dd0:ec00:c25:c25:dd4e:f828/1282c19:dd:dd0:ec00:c25:c25:dd4e:f828
422c19:dd:dd0:ec00:c25:c25:dd4e:f829/1282c19:dd:dd0:ec00:c25:c25:dd4e:f829
432c19:dd:dd0:ec00:c25:c25:dd4e:f82a/1282c19:dd:dd0:ec00:c25:c25:dd4e:f82a
442c19:dd:dd0:ec00:c25:c25:dd4e:f82b/1282c19:dd:dd0:ec00:c25:c25:dd4e:f82b
452c19:dd:dd0:ec00:c25:c25:dd4e:f82c/1282c19:dd:dd0:ec00:c25:c25:dd4e:f82c
462c19:dd:dd0:ec00:c25:c25:dd4e:f82d/1282c19:dd:dd0:ec00:c25:c25:dd4e:f82d
472c19:dd:dd0:ec00:c25:c25:dd4e:f82e/1282c19:dd:dd0:ec00:c25:c25:dd4e:f82e
482c19:dd:dd0:ec00:c25:c25:dd4e:f82f/1282c19:dd:dd0:ec00:c25:c25:dd4e:f82f
492c19:dd:dd0:ec00:c25:c25:dd4e:f830/1282c19:dd:dd0:ec00:c25:c25:dd4e:f830
502c19:dd:dd0:ec00:c25:c25:dd4e:f831/1282c19:dd:dd0:ec00:c25:c25:dd4e:f831
512c19:dd:dd0:ec00:c25:c25:dd4e:f832/1282c19:dd:dd0:ec00:c25:c25:dd4e:f832
522c19:dd:dd0:ec00:c25:c25:dd4e:f833/1282c19:dd:dd0:ec00:c25:c25:dd4e:f833
532c19:dd:dd0:ec00:c25:c25:dd4e:f834/1282c19:dd:dd0:ec00:c25:c25:dd4e:f834
542c19:dd:dd0:ec00:c25:c25:dd4e:f835/1282c19:dd:dd0:ec00:c25:c25:dd4e:f835
552c19:dd:dd0:ec00:c25:c25:dd4e:f836/1282c19:dd:dd0:ec00:c25:c25:dd4e:f836
562c19:dd:dd0:ec00:c25:c25:dd4e:f837/1282c19:dd:dd0:ec00:c25:c25:dd4e:f837
572c19:dd:dd0:ec00:c25:c25:dd4e:f838/1282c19:dd:dd0:ec00:c25:c25:dd4e:f838
582c19:dd:dd0:ec00:c25:c25:dd4e:f839/1282c19:dd:dd0:ec00:c25:c25:dd4e:f839
592c19:dd:dd0:ec00:c25:c25:dd4e:f83a/1282c19:dd:dd0:ec00:c25:c25:dd4e:f83a
602c19:dd:dd0:ec00:c25:c25:dd4e:f83b/1282c19:dd:dd0:ec00:c25:c25:dd4e:f83b
612c19:dd:dd0:ec00:c25:c25:dd4e:f83c/1282c19:dd:dd0:ec00:c25:c25:dd4e:f83c
622c19:dd:dd0:ec00:c25:c25:dd4e:f83d/1282c19:dd:dd0:ec00:c25:c25:dd4e:f83d
632c19:dd:dd0:ec00:c25:c25:dd4e:f83e/1282c19:dd:dd0:ec00:c25:c25:dd4e:f83e
642c19:dd:dd0:ec00:c25:c25:dd4e:f83f/1282c19:dd:dd0:ec00:c25:c25:dd4e:f83f
652c19:dd:dd0:ec00:c25:c25:dd4e:f840/1282c19:dd:dd0:ec00:c25:c25:dd4e:f840
662c19:dd:dd0:ec00:c25:c25:dd4e:f841/1282c19:dd:dd0:ec00:c25:c25:dd4e:f841
672c19:dd:dd0:ec00:c25:c25:dd4e:f842/1282c19:dd:dd0:ec00:c25:c25:dd4e:f842
682c19:dd:dd0:ec00:c25:c25:dd4e:f843/1282c19:dd:dd0:ec00:c25:c25:dd4e:f843
692c19:dd:dd0:ec00:c25:c25:dd4e:f844/1282c19:dd:dd0:ec00:c25:c25:dd4e:f844
702c19:dd:dd0:ec00:c25:c25:dd4e:f845/1282c19:dd:dd0:ec00:c25:c25:dd4e:f845
712c19:dd:dd0:ec00:c25:c25:dd4e:f846/1282c19:dd:dd0:ec00:c25:c25:dd4e:f846
722c19:dd:dd0:ec00:c25:c25:dd4e:f847/1282c19:dd:dd0:ec00:c25:c25:dd4e:f847
732c19:dd:dd0:ec00:c25:c25:dd4e:f848/1282c19:dd:dd0:ec00:c25:c25:dd4e:f848
742c19:dd:dd0:ec00:c25:c25:dd4e:f849/1282c19:dd:dd0:ec00:c25:c25:dd4e:f849
752c19:dd:dd0:ec00:c25:c25:dd4e:f84a/1282c19:dd:dd0:ec00:c25:c25:dd4e:f84a
762c19:dd:dd0:ec00:c25:c25:dd4e:f84b/1282c19:dd:dd0:ec00:c25:c25:dd4e:f84b
772c19:dd:dd0:ec00:c25:c25:dd4e:f84c/1282c19:dd:dd0:ec00:c25:c25:dd4e:f84c
782c19:dd:dd0:ec00:c25:c25:dd4e:f84d/1282c19:dd:dd0:ec00:c25:c25:dd4e:f84d
792c19:dd:dd0:ec00:c25:c25:dd4e:f84e/1282c19:dd:dd0:ec00:c25:c25:dd4e:f84e
802c19:dd:dd0:ec00:c25:c25:dd4e:f84f/1282c19:dd:dd0:ec00:c25:c25:dd4e:f84f
812c19:dd:dd0:ec00:c25:c25:dd4e:f850/1282c19:dd:dd0:ec00:c25:c25:dd4e:f850
822c19:dd:dd0:ec00:c25:c25:dd4e:f851/1282c19:dd:dd0:ec00:c25:c25:dd4e:f851
832c19:dd:dd0:ec00:c25:c25:dd4e:f852/1282c19:dd:dd0:ec00:c25:c25:dd4e:f852
842c19:dd:dd0:ec00:c25:c25:dd4e:f853/1282c19:dd:dd0:ec00:c25:c25:dd4e:f853
852c19:dd:dd0:ec00:c25:c25:dd4e:f854/1282c19:dd:dd0:ec00:c25:c25:dd4e:f854
862c19:dd:dd0:ec00:c25:c25:dd4e:f855/1282c19:dd:dd0:ec00:c25:c25:dd4e:f855
872c19:dd:dd0:ec00:c25:c25:dd4e:f856/1282c19:dd:dd0:ec00:c25:c25:dd4e:f856
882c19:dd:dd0:ec00:c25:c25:dd4e:f857/1282c19:dd:dd0:ec00:c25:c25:dd4e:f857
892c19:dd:dd0:ec00:c25:c25:dd4e:f858/1282c19:dd:dd0:ec00:c25:c25:dd4e:f858
902c19:dd:dd0:ec00:c25:c25:dd4e:f859/1282c19:dd:dd0:ec00:c25:c25:dd4e:f859
912c19:dd:dd0:ec00:c25:c25:dd4e:f85a/1282c19:dd:dd0:ec00:c25:c25:dd4e:f85a
922c19:dd:dd0:ec00:c25:c25:dd4e:f85b/1282c19:dd:dd0:ec00:c25:c25:dd4e:f85b
932c19:dd:dd0:ec00:c25:c25:dd4e:f85c/1282c19:dd:dd0:ec00:c25:c25:dd4e:f85c
942c19:dd:dd0:ec00:c25:c25:dd4e:f85d/1282c19:dd:dd0:ec00:c25:c25:dd4e:f85d
952c19:dd:dd0:ec00:c25:c25:dd4e:f85e/1282c19:dd:dd0:ec00:c25:c25:dd4e:f85e
962c19:dd:dd0:ec00:c25:c25:dd4e:f85f/1282c19:dd:dd0:ec00:c25:c25:dd4e:f85f
972c19:dd:dd0:ec00:c25:c25:dd4e:f860/1282c19:dd:dd0:ec00:c25:c25:dd4e:f860
982c19:dd:dd0:ec00:c25:c25:dd4e:f861/1282c19:dd:dd0:ec00:c25:c25:dd4e:f861
992c19:dd:dd0:ec00:c25:c25:dd4e:f862/1282c19:dd:dd0:ec00:c25:c25:dd4e:f862
1002c19:dd:dd0:ec00:c25:c25:dd4e:f863/1282c19:dd:dd0:ec00:c25:c25:dd4e:f863
1012c19:dd:dd0:ec00:c25:c25:dd4e:f864/1282c19:dd:dd0:ec00:c25:c25:dd4e:f864
1022c19:dd:dd0:ec00:c25:c25:dd4e:f865/1282c19:dd:dd0:ec00:c25:c25:dd4e:f865
1032c19:dd:dd0:ec00:c25:c25:dd4e:f866/1282c19:dd:dd0:ec00:c25:c25:dd4e:f866
1042c19:dd:dd0:ec00:c25:c25:dd4e:f867/1282c19:dd:dd0:ec00:c25:c25:dd4e:f867
1052c19:dd:dd0:ec00:c25:c25:dd4e:f868/1282c19:dd:dd0:ec00:c25:c25:dd4e:f868
1062c19:dd:dd0:ec00:c25:c25:dd4e:f869/1282c19:dd:dd0:ec00:c25:c25:dd4e:f869
1072c19:dd:dd0:ec00:c25:c25:dd4e:f86a/1282c19:dd:dd0:ec00:c25:c25:dd4e:f86a
1082c19:dd:dd0:ec00:c25:c25:dd4e:f86b/1282c19:dd:dd0:ec00:c25:c25:dd4e:f86b
1092c19:dd:dd0:ec00:c25:c25:dd4e:f86c/1282c19:dd:dd0:ec00:c25:c25:dd4e:f86c
1102c19:dd:dd0:ec00:c25:c25:dd4e:f86d/1282c19:dd:dd0:ec00:c25:c25:dd4e:f86d
1112c19:dd:dd0:ec00:c25:c25:dd4e:f86e/1282c19:dd:dd0:ec00:c25:c25:dd4e:f86e
1122c19:dd:dd0:ec00:c25:c25:dd4e:f86f/1282c19:dd:dd0:ec00:c25:c25:dd4e:f86f
1132c19:dd:dd0:ec00:c25:c25:dd4e:f870/1282c19:dd:dd0:ec00:c25:c25:dd4e:f870
1142c19:dd:dd0:ec00:c25:c25:dd4e:f871/1282c19:dd:dd0:ec00:c25:c25:dd4e:f871
1152c19:dd:dd0:ec00:c25:c25:dd4e:f872/1282c19:dd:dd0:ec00:c25:c25:dd4e:f872
1162c19:dd:dd0:ec00:c25:c25:dd4e:f873/1282c19:dd:dd0:ec00:c25:c25:dd4e:f873
1172c19:dd:dd0:ec00:c25:c25:dd4e:f874/1282c19:dd:dd0:ec00:c25:c25:dd4e:f874
1182c19:dd:dd0:ec00:c25:c25:dd4e:f875/1282c19:dd:dd0:ec00:c25:c25:dd4e:f875
1192c19:dd:dd0:ec00:c25:c25:dd4e:f876/1282c19:dd:dd0:ec00:c25:c25:dd4e:f876
1202c19:dd:dd0:ec00:c25:c25:dd4e:f877/1282c19:dd:dd0:ec00:c25:c25:dd4e:f877
1212c19:dd:dd0:ec00:c25:c25:dd4e:f878/1282c19:dd:dd0:ec00:c25:c25:dd4e:f878
1222c19:dd:dd0:ec00:c25:c25:dd4e:f879/1282c19:dd:dd0:ec00:c25:c25:dd4e:f879
1232c19:dd:dd0:ec00:c25:c25:dd4e:f87a/1282c19:dd:dd0:ec00:c25:c25:dd4e:f87a
1242c19:dd:dd0:ec00:c25:c25:dd4e:f87b/1282c19:dd:dd0:ec00:c25:c25:dd4e:f87b
1252c19:dd:dd0:ec00:c25:c25:dd4e:f87c/1282c19:dd:dd0:ec00:c25:c25:dd4e:f87c
1262c19:dd:dd0:ec00:c25:c25:dd4e:f87d/1282c19:dd:dd0:ec00:c25:c25:dd4e:f87d
1272c19:dd:dd0:ec00:c25:c25:dd4e:f87e/1282c19:dd:dd0:ec00:c25:c25:dd4e:f87e
1282c19:dd:dd0:ec00:c25:c25:dd4e:f87f/1282c19:dd:dd0:ec00:c25:c25:dd4e:f87f
1292c19:dd:dd0:ec00:c25:c25:dd4e:f880/1282c19:dd:dd0:ec00:c25:c25:dd4e:f880
1302c19:dd:dd0:ec00:c25:c25:dd4e:f881/1282c19:dd:dd0:ec00:c25:c25:dd4e:f881
1312c19:dd:dd0:ec00:c25:c25:dd4e:f882/1282c19:dd:dd0:ec00:c25:c25:dd4e:f882
1322c19:dd:dd0:ec00:c25:c25:dd4e:f883/1282c19:dd:dd0:ec00:c25:c25:dd4e:f883
1332c19:dd:dd0:ec00:c25:c25:dd4e:f884/1282c19:dd:dd0:ec00:c25:c25:dd4e:f884
1342c19:dd:dd0:ec00:c25:c25:dd4e:f885/1282c19:dd:dd0:ec00:c25:c25:dd4e:f885
1352c19:dd:dd0:ec00:c25:c25:dd4e:f886/1282c19:dd:dd0:ec00:c25:c25:dd4e:f886
1362c19:dd:dd0:ec00:c25:c25:dd4e:f887/1282c19:dd:dd0:ec00:c25:c25:dd4e:f887
1372c19:dd:dd0:ec00:c25:c25:dd4e:f888/1282c19:dd:dd0:ec00:c25:c25:dd4e:f888
1382c19:dd:dd0:ec00:c25:c25:dd4e:f889/1282c19:dd:dd0:ec00:c25:c25:dd4e:f889
1392c19:dd:dd0:ec00:c25:c25:dd4e:f88a/1282c19:dd:dd0:ec00:c25:c25:dd4e:f88a
1402c19:dd:dd0:ec00:c25:c25:dd4e:f88b/1282c19:dd:dd0:ec00:c25:c25:dd4e:f88b
1412c19:dd:dd0:ec00:c25:c25:dd4e:f88c/1282c19:dd:dd0:ec00:c25:c25:dd4e:f88c
1422c19:dd:dd0:ec00:c25:c25:dd4e:f88d/1282c19:dd:dd0:ec00:c25:c25:dd4e:f88d
1432c19:dd:dd0:ec00:c25:c25:dd4e:f88e/1282c19:dd:dd0:ec00:c25:c25:dd4e:f88e
1442c19:dd:dd0:ec00:c25:c25:dd4e:f88f/1282c19:dd:dd0:ec00:c25:c25:dd4e:f88f
1452c19:dd:dd0:ec00:c25:c25:dd4e:f890/1282c19:dd:dd0:ec00:c25:c25:dd4e:f890
1462c19:dd:dd0:ec00:c25:c25:dd4e:f891/1282c19:dd:dd0:ec00:c25:c25:dd4e:f891
1472c19:dd:dd0:ec00:c25:c25:dd4e:f892/1282c19:dd:dd0:ec00:c25:c25:dd4e:f892
1482c19:dd:dd0:ec00:c25:c25:dd4e:f893/1282c19:dd:dd0:ec00:c25:c25:dd4e:f893
1492c19:dd:dd0:ec00:c25:c25:dd4e:f894/1282c19:dd:dd0:ec00:c25:c25:dd4e:f894
1502c19:dd:dd0:ec00:c25:c25:dd4e:f895/1282c19:dd:dd0:ec00:c25:c25:dd4e:f895
1512c19:dd:dd0:ec00:c25:c25:dd4e:f896/1282c19:dd:dd0:ec00:c25:c25:dd4e:f896
1522c19:dd:dd0:ec00:c25:c25:dd4e:f897/1282c19:dd:dd0:ec00:c25:c25:dd4e:f897
1532c19:dd:dd0:ec00:c25:c25:dd4e:f898/1282c19:dd:dd0:ec00:c25:c25:dd4e:f898
1542c19:dd:dd0:ec00:c25:c25:dd4e:f899/1282c19:dd:dd0:ec00:c25:c25:dd4e:f899
1552c19:dd:dd0:ec00:c25:c25:dd4e:f89a/1282c19:dd:dd0:ec00:c25:c25:dd4e:f89a
1562c19:dd:dd0:ec00:c25:c25:dd4e:f89b/1282c19:dd:dd0:ec00:c25:c25:dd4e:f89b
1572c19:dd:dd0:ec00:c25:c25:dd4e:f89c/1282c19:dd:dd0:ec00:c25:c25:dd4e:f89c
1582c19:dd:dd0:ec00:c25:c25:dd4e:f89d/1282c19:dd:dd0:ec00:c25:c25:dd4e:f89d
1592c19:dd:dd0:ec00:c25:c25:dd4e:f89e/1282c19:dd:dd0:ec00:c25:c25:dd4e:f89e
1602c19:dd:dd0:ec00:c25:c25:dd4e:f89f/1282c19:dd:dd0:ec00:c25:c25:dd4e:f89f
1612c19:dd:dd0:ec00:c25:c25:dd4e:f8a0/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8a0
1622c19:dd:dd0:ec00:c25:c25:dd4e:f8a1/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8a1
1632c19:dd:dd0:ec00:c25:c25:dd4e:f8a2/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8a2
1642c19:dd:dd0:ec00:c25:c25:dd4e:f8a3/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8a3
1652c19:dd:dd0:ec00:c25:c25:dd4e:f8a4/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8a4
1662c19:dd:dd0:ec00:c25:c25:dd4e:f8a5/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8a5
1672c19:dd:dd0:ec00:c25:c25:dd4e:f8a6/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8a6
1682c19:dd:dd0:ec00:c25:c25:dd4e:f8a7/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8a7
1692c19:dd:dd0:ec00:c25:c25:dd4e:f8a8/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8a8
1702c19:dd:dd0:ec00:c25:c25:dd4e:f8a9/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8a9
1712c19:dd:dd0:ec00:c25:c25:dd4e:f8aa/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8aa
1722c19:dd:dd0:ec00:c25:c25:dd4e:f8ab/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8ab
1732c19:dd:dd0:ec00:c25:c25:dd4e:f8ac/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8ac
1742c19:dd:dd0:ec00:c25:c25:dd4e:f8ad/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8ad
1752c19:dd:dd0:ec00:c25:c25:dd4e:f8ae/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8ae
1762c19:dd:dd0:ec00:c25:c25:dd4e:f8af/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8af
1772c19:dd:dd0:ec00:c25:c25:dd4e:f8b0/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8b0
1782c19:dd:dd0:ec00:c25:c25:dd4e:f8b1/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8b1
1792c19:dd:dd0:ec00:c25:c25:dd4e:f8b2/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8b2
1802c19:dd:dd0:ec00:c25:c25:dd4e:f8b3/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8b3
1812c19:dd:dd0:ec00:c25:c25:dd4e:f8b4/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8b4
1822c19:dd:dd0:ec00:c25:c25:dd4e:f8b5/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8b5
1832c19:dd:dd0:ec00:c25:c25:dd4e:f8b6/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8b6
1842c19:dd:dd0:ec00:c25:c25:dd4e:f8b7/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8b7
1852c19:dd:dd0:ec00:c25:c25:dd4e:f8b8/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8b8
1862c19:dd:dd0:ec00:c25:c25:dd4e:f8b9/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8b9
1872c19:dd:dd0:ec00:c25:c25:dd4e:f8ba/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8ba
1882c19:dd:dd0:ec00:c25:c25:dd4e:f8bb/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8bb
1892c19:dd:dd0:ec00:c25:c25:dd4e:f8bc/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8bc
1902c19:dd:dd0:ec00:c25:c25:dd4e:f8bd/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8bd
1912c19:dd:dd0:ec00:c25:c25:dd4e:f8be/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8be
1922c19:dd:dd0:ec00:c25:c25:dd4e:f8bf/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8bf
1932c19:dd:dd0:ec00:c25:c25:dd4e:f8c0/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8c0
1942c19:dd:dd0:ec00:c25:c25:dd4e:f8c1/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8c1
1952c19:dd:dd0:ec00:c25:c25:dd4e:f8c2/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8c2
1962c19:dd:dd0:ec00:c25:c25:dd4e:f8c3/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8c3
1972c19:dd:dd0:ec00:c25:c25:dd4e:f8c4/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8c4
1982c19:dd:dd0:ec00:c25:c25:dd4e:f8c5/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8c5
1992c19:dd:dd0:ec00:c25:c25:dd4e:f8c6/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8c6
2002c19:dd:dd0:ec00:c25:c25:dd4e:f8c7/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8c7
2012c19:dd:dd0:ec00:c25:c25:dd4e:f8c8/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8c8
2022c19:dd:dd0:ec00:c25:c25:dd4e:f8c9/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8c9
2032c19:dd:dd0:ec00:c25:c25:dd4e:f8ca/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8ca
2042c19:dd:dd0:ec00:c25:c25:dd4e:f8cb/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8cb
2052c19:dd:dd0:ec00:c25:c25:dd4e:f8cc/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8cc
2062c19:dd:dd0:ec00:c25:c25:dd4e:f8cd/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8cd
2072c19:dd:dd0:ec00:c25:c25:dd4e:f8ce/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8ce
2082c19:dd:dd0:ec00:c25:c25:dd4e:f8cf/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8cf
2092c19:dd:dd0:ec00:c25:c25:dd4e:f8d0/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8d0
2102c19:dd:dd0:ec00:c25:c25:dd4e:f8d1/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8d1
2112c19:dd:dd0:ec00:c25:c25:dd4e:f8d2/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8d2
2122c19:dd:dd0:ec00:c25:c25:dd4e:f8d3/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8d3
2132c19:dd:dd0:ec00:c25:c25:dd4e:f8d4/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8d4
2142c19:dd:dd0:ec00:c25:c25:dd4e:f8d5/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8d5
2152c19:dd:dd0:ec00:c25:c25:dd4e:f8d6/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8d6
2162c19:dd:dd0:ec00:c25:c25:dd4e:f8d7/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8d7
2172c19:dd:dd0:ec00:c25:c25:dd4e:f8d8/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8d8
2182c19:dd:dd0:ec00:c25:c25:dd4e:f8d9/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8d9
2192c19:dd:dd0:ec00:c25:c25:dd4e:f8da/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8da
2202c19:dd:dd0:ec00:c25:c25:dd4e:f8db/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8db
2212c19:dd:dd0:ec00:c25:c25:dd4e:f8dc/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8dc
2222c19:dd:dd0:ec00:c25:c25:dd4e:f8dd/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8dd
2232c19:dd:dd0:ec00:c25:c25:dd4e:f8de/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8de
2242c19:dd:dd0:ec00:c25:c25:dd4e:f8df/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8df
2252c19:dd:dd0:ec00:c25:c25:dd4e:f8e0/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8e0
2262c19:dd:dd0:ec00:c25:c25:dd4e:f8e1/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8e1
2272c19:dd:dd0:ec00:c25:c25:dd4e:f8e2/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8e2
2282c19:dd:dd0:ec00:c25:c25:dd4e:f8e3/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8e3
2292c19:dd:dd0:ec00:c25:c25:dd4e:f8e4/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8e4
2302c19:dd:dd0:ec00:c25:c25:dd4e:f8e5/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8e5
2312c19:dd:dd0:ec00:c25:c25:dd4e:f8e6/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8e6
2322c19:dd:dd0:ec00:c25:c25:dd4e:f8e7/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8e7
2332c19:dd:dd0:ec00:c25:c25:dd4e:f8e8/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8e8
2342c19:dd:dd0:ec00:c25:c25:dd4e:f8e9/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8e9
2352c19:dd:dd0:ec00:c25:c25:dd4e:f8ea/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8ea
2362c19:dd:dd0:ec00:c25:c25:dd4e:f8eb/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8eb
2372c19:dd:dd0:ec00:c25:c25:dd4e:f8ec/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8ec
2382c19:dd:dd0:ec00:c25:c25:dd4e:f8ed/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8ed
2392c19:dd:dd0:ec00:c25:c25:dd4e:f8ee/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8ee
2402c19:dd:dd0:ec00:c25:c25:dd4e:f8ef/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8ef
2412c19:dd:dd0:ec00:c25:c25:dd4e:f8f0/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8f0
2422c19:dd:dd0:ec00:c25:c25:dd4e:f8f1/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8f1
2432c19:dd:dd0:ec00:c25:c25:dd4e:f8f2/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8f2
2442c19:dd:dd0:ec00:c25:c25:dd4e:f8f3/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8f3
2452c19:dd:dd0:ec00:c25:c25:dd4e:f8f4/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8f4
2462c19:dd:dd0:ec00:c25:c25:dd4e:f8f5/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8f5
2472c19:dd:dd0:ec00:c25:c25:dd4e:f8f6/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8f6
2482c19:dd:dd0:ec00:c25:c25:dd4e:f8f7/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8f7
2492c19:dd:dd0:ec00:c25:c25:dd4e:f8f8/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8f8
2502c19:dd:dd0:ec00:c25:c25:dd4e:f8f9/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8f9
2512c19:dd:dd0:ec00:c25:c25:dd4e:f8fa/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8fa
2522c19:dd:dd0:ec00:c25:c25:dd4e:f8fb/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8fb
2532c19:dd:dd0:ec00:c25:c25:dd4e:f8fc/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8fc
2542c19:dd:dd0:ec00:c25:c25:dd4e:f8fd/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8fd
2552c19:dd:dd0:ec00:c25:c25:dd4e:f8fe/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8fe
2562c19:dd:dd0:ec00:c25:c25:dd4e:f8ff/1282c19:dd:dd0:ec00:c25:c25:dd4e:f8ff

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.