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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:c25b:d00a:c800/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:c800
Last address
2c19:dd:d9:dd:c25:c25b:d00a:c8ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:c800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.c.a.0.0.d.b.5.2.c.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25b:d00a:c800/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:c800/1282c19:dd:d9:dd:c25:c25b:d00a:c800
22c19:dd:d9:dd:c25:c25b:d00a:c801/1282c19:dd:d9:dd:c25:c25b:d00a:c801
32c19:dd:d9:dd:c25:c25b:d00a:c802/1282c19:dd:d9:dd:c25:c25b:d00a:c802
42c19:dd:d9:dd:c25:c25b:d00a:c803/1282c19:dd:d9:dd:c25:c25b:d00a:c803
52c19:dd:d9:dd:c25:c25b:d00a:c804/1282c19:dd:d9:dd:c25:c25b:d00a:c804
62c19:dd:d9:dd:c25:c25b:d00a:c805/1282c19:dd:d9:dd:c25:c25b:d00a:c805
72c19:dd:d9:dd:c25:c25b:d00a:c806/1282c19:dd:d9:dd:c25:c25b:d00a:c806
82c19:dd:d9:dd:c25:c25b:d00a:c807/1282c19:dd:d9:dd:c25:c25b:d00a:c807
92c19:dd:d9:dd:c25:c25b:d00a:c808/1282c19:dd:d9:dd:c25:c25b:d00a:c808
102c19:dd:d9:dd:c25:c25b:d00a:c809/1282c19:dd:d9:dd:c25:c25b:d00a:c809
112c19:dd:d9:dd:c25:c25b:d00a:c80a/1282c19:dd:d9:dd:c25:c25b:d00a:c80a
122c19:dd:d9:dd:c25:c25b:d00a:c80b/1282c19:dd:d9:dd:c25:c25b:d00a:c80b
132c19:dd:d9:dd:c25:c25b:d00a:c80c/1282c19:dd:d9:dd:c25:c25b:d00a:c80c
142c19:dd:d9:dd:c25:c25b:d00a:c80d/1282c19:dd:d9:dd:c25:c25b:d00a:c80d
152c19:dd:d9:dd:c25:c25b:d00a:c80e/1282c19:dd:d9:dd:c25:c25b:d00a:c80e
162c19:dd:d9:dd:c25:c25b:d00a:c80f/1282c19:dd:d9:dd:c25:c25b:d00a:c80f
172c19:dd:d9:dd:c25:c25b:d00a:c810/1282c19:dd:d9:dd:c25:c25b:d00a:c810
182c19:dd:d9:dd:c25:c25b:d00a:c811/1282c19:dd:d9:dd:c25:c25b:d00a:c811
192c19:dd:d9:dd:c25:c25b:d00a:c812/1282c19:dd:d9:dd:c25:c25b:d00a:c812
202c19:dd:d9:dd:c25:c25b:d00a:c813/1282c19:dd:d9:dd:c25:c25b:d00a:c813
212c19:dd:d9:dd:c25:c25b:d00a:c814/1282c19:dd:d9:dd:c25:c25b:d00a:c814
222c19:dd:d9:dd:c25:c25b:d00a:c815/1282c19:dd:d9:dd:c25:c25b:d00a:c815
232c19:dd:d9:dd:c25:c25b:d00a:c816/1282c19:dd:d9:dd:c25:c25b:d00a:c816
242c19:dd:d9:dd:c25:c25b:d00a:c817/1282c19:dd:d9:dd:c25:c25b:d00a:c817
252c19:dd:d9:dd:c25:c25b:d00a:c818/1282c19:dd:d9:dd:c25:c25b:d00a:c818
262c19:dd:d9:dd:c25:c25b:d00a:c819/1282c19:dd:d9:dd:c25:c25b:d00a:c819
272c19:dd:d9:dd:c25:c25b:d00a:c81a/1282c19:dd:d9:dd:c25:c25b:d00a:c81a
282c19:dd:d9:dd:c25:c25b:d00a:c81b/1282c19:dd:d9:dd:c25:c25b:d00a:c81b
292c19:dd:d9:dd:c25:c25b:d00a:c81c/1282c19:dd:d9:dd:c25:c25b:d00a:c81c
302c19:dd:d9:dd:c25:c25b:d00a:c81d/1282c19:dd:d9:dd:c25:c25b:d00a:c81d
312c19:dd:d9:dd:c25:c25b:d00a:c81e/1282c19:dd:d9:dd:c25:c25b:d00a:c81e
322c19:dd:d9:dd:c25:c25b:d00a:c81f/1282c19:dd:d9:dd:c25:c25b:d00a:c81f
332c19:dd:d9:dd:c25:c25b:d00a:c820/1282c19:dd:d9:dd:c25:c25b:d00a:c820
342c19:dd:d9:dd:c25:c25b:d00a:c821/1282c19:dd:d9:dd:c25:c25b:d00a:c821
352c19:dd:d9:dd:c25:c25b:d00a:c822/1282c19:dd:d9:dd:c25:c25b:d00a:c822
362c19:dd:d9:dd:c25:c25b:d00a:c823/1282c19:dd:d9:dd:c25:c25b:d00a:c823
372c19:dd:d9:dd:c25:c25b:d00a:c824/1282c19:dd:d9:dd:c25:c25b:d00a:c824
382c19:dd:d9:dd:c25:c25b:d00a:c825/1282c19:dd:d9:dd:c25:c25b:d00a:c825
392c19:dd:d9:dd:c25:c25b:d00a:c826/1282c19:dd:d9:dd:c25:c25b:d00a:c826
402c19:dd:d9:dd:c25:c25b:d00a:c827/1282c19:dd:d9:dd:c25:c25b:d00a:c827
412c19:dd:d9:dd:c25:c25b:d00a:c828/1282c19:dd:d9:dd:c25:c25b:d00a:c828
422c19:dd:d9:dd:c25:c25b:d00a:c829/1282c19:dd:d9:dd:c25:c25b:d00a:c829
432c19:dd:d9:dd:c25:c25b:d00a:c82a/1282c19:dd:d9:dd:c25:c25b:d00a:c82a
442c19:dd:d9:dd:c25:c25b:d00a:c82b/1282c19:dd:d9:dd:c25:c25b:d00a:c82b
452c19:dd:d9:dd:c25:c25b:d00a:c82c/1282c19:dd:d9:dd:c25:c25b:d00a:c82c
462c19:dd:d9:dd:c25:c25b:d00a:c82d/1282c19:dd:d9:dd:c25:c25b:d00a:c82d
472c19:dd:d9:dd:c25:c25b:d00a:c82e/1282c19:dd:d9:dd:c25:c25b:d00a:c82e
482c19:dd:d9:dd:c25:c25b:d00a:c82f/1282c19:dd:d9:dd:c25:c25b:d00a:c82f
492c19:dd:d9:dd:c25:c25b:d00a:c830/1282c19:dd:d9:dd:c25:c25b:d00a:c830
502c19:dd:d9:dd:c25:c25b:d00a:c831/1282c19:dd:d9:dd:c25:c25b:d00a:c831
512c19:dd:d9:dd:c25:c25b:d00a:c832/1282c19:dd:d9:dd:c25:c25b:d00a:c832
522c19:dd:d9:dd:c25:c25b:d00a:c833/1282c19:dd:d9:dd:c25:c25b:d00a:c833
532c19:dd:d9:dd:c25:c25b:d00a:c834/1282c19:dd:d9:dd:c25:c25b:d00a:c834
542c19:dd:d9:dd:c25:c25b:d00a:c835/1282c19:dd:d9:dd:c25:c25b:d00a:c835
552c19:dd:d9:dd:c25:c25b:d00a:c836/1282c19:dd:d9:dd:c25:c25b:d00a:c836
562c19:dd:d9:dd:c25:c25b:d00a:c837/1282c19:dd:d9:dd:c25:c25b:d00a:c837
572c19:dd:d9:dd:c25:c25b:d00a:c838/1282c19:dd:d9:dd:c25:c25b:d00a:c838
582c19:dd:d9:dd:c25:c25b:d00a:c839/1282c19:dd:d9:dd:c25:c25b:d00a:c839
592c19:dd:d9:dd:c25:c25b:d00a:c83a/1282c19:dd:d9:dd:c25:c25b:d00a:c83a
602c19:dd:d9:dd:c25:c25b:d00a:c83b/1282c19:dd:d9:dd:c25:c25b:d00a:c83b
612c19:dd:d9:dd:c25:c25b:d00a:c83c/1282c19:dd:d9:dd:c25:c25b:d00a:c83c
622c19:dd:d9:dd:c25:c25b:d00a:c83d/1282c19:dd:d9:dd:c25:c25b:d00a:c83d
632c19:dd:d9:dd:c25:c25b:d00a:c83e/1282c19:dd:d9:dd:c25:c25b:d00a:c83e
642c19:dd:d9:dd:c25:c25b:d00a:c83f/1282c19:dd:d9:dd:c25:c25b:d00a:c83f
652c19:dd:d9:dd:c25:c25b:d00a:c840/1282c19:dd:d9:dd:c25:c25b:d00a:c840
662c19:dd:d9:dd:c25:c25b:d00a:c841/1282c19:dd:d9:dd:c25:c25b:d00a:c841
672c19:dd:d9:dd:c25:c25b:d00a:c842/1282c19:dd:d9:dd:c25:c25b:d00a:c842
682c19:dd:d9:dd:c25:c25b:d00a:c843/1282c19:dd:d9:dd:c25:c25b:d00a:c843
692c19:dd:d9:dd:c25:c25b:d00a:c844/1282c19:dd:d9:dd:c25:c25b:d00a:c844
702c19:dd:d9:dd:c25:c25b:d00a:c845/1282c19:dd:d9:dd:c25:c25b:d00a:c845
712c19:dd:d9:dd:c25:c25b:d00a:c846/1282c19:dd:d9:dd:c25:c25b:d00a:c846
722c19:dd:d9:dd:c25:c25b:d00a:c847/1282c19:dd:d9:dd:c25:c25b:d00a:c847
732c19:dd:d9:dd:c25:c25b:d00a:c848/1282c19:dd:d9:dd:c25:c25b:d00a:c848
742c19:dd:d9:dd:c25:c25b:d00a:c849/1282c19:dd:d9:dd:c25:c25b:d00a:c849
752c19:dd:d9:dd:c25:c25b:d00a:c84a/1282c19:dd:d9:dd:c25:c25b:d00a:c84a
762c19:dd:d9:dd:c25:c25b:d00a:c84b/1282c19:dd:d9:dd:c25:c25b:d00a:c84b
772c19:dd:d9:dd:c25:c25b:d00a:c84c/1282c19:dd:d9:dd:c25:c25b:d00a:c84c
782c19:dd:d9:dd:c25:c25b:d00a:c84d/1282c19:dd:d9:dd:c25:c25b:d00a:c84d
792c19:dd:d9:dd:c25:c25b:d00a:c84e/1282c19:dd:d9:dd:c25:c25b:d00a:c84e
802c19:dd:d9:dd:c25:c25b:d00a:c84f/1282c19:dd:d9:dd:c25:c25b:d00a:c84f
812c19:dd:d9:dd:c25:c25b:d00a:c850/1282c19:dd:d9:dd:c25:c25b:d00a:c850
822c19:dd:d9:dd:c25:c25b:d00a:c851/1282c19:dd:d9:dd:c25:c25b:d00a:c851
832c19:dd:d9:dd:c25:c25b:d00a:c852/1282c19:dd:d9:dd:c25:c25b:d00a:c852
842c19:dd:d9:dd:c25:c25b:d00a:c853/1282c19:dd:d9:dd:c25:c25b:d00a:c853
852c19:dd:d9:dd:c25:c25b:d00a:c854/1282c19:dd:d9:dd:c25:c25b:d00a:c854
862c19:dd:d9:dd:c25:c25b:d00a:c855/1282c19:dd:d9:dd:c25:c25b:d00a:c855
872c19:dd:d9:dd:c25:c25b:d00a:c856/1282c19:dd:d9:dd:c25:c25b:d00a:c856
882c19:dd:d9:dd:c25:c25b:d00a:c857/1282c19:dd:d9:dd:c25:c25b:d00a:c857
892c19:dd:d9:dd:c25:c25b:d00a:c858/1282c19:dd:d9:dd:c25:c25b:d00a:c858
902c19:dd:d9:dd:c25:c25b:d00a:c859/1282c19:dd:d9:dd:c25:c25b:d00a:c859
912c19:dd:d9:dd:c25:c25b:d00a:c85a/1282c19:dd:d9:dd:c25:c25b:d00a:c85a
922c19:dd:d9:dd:c25:c25b:d00a:c85b/1282c19:dd:d9:dd:c25:c25b:d00a:c85b
932c19:dd:d9:dd:c25:c25b:d00a:c85c/1282c19:dd:d9:dd:c25:c25b:d00a:c85c
942c19:dd:d9:dd:c25:c25b:d00a:c85d/1282c19:dd:d9:dd:c25:c25b:d00a:c85d
952c19:dd:d9:dd:c25:c25b:d00a:c85e/1282c19:dd:d9:dd:c25:c25b:d00a:c85e
962c19:dd:d9:dd:c25:c25b:d00a:c85f/1282c19:dd:d9:dd:c25:c25b:d00a:c85f
972c19:dd:d9:dd:c25:c25b:d00a:c860/1282c19:dd:d9:dd:c25:c25b:d00a:c860
982c19:dd:d9:dd:c25:c25b:d00a:c861/1282c19:dd:d9:dd:c25:c25b:d00a:c861
992c19:dd:d9:dd:c25:c25b:d00a:c862/1282c19:dd:d9:dd:c25:c25b:d00a:c862
1002c19:dd:d9:dd:c25:c25b:d00a:c863/1282c19:dd:d9:dd:c25:c25b:d00a:c863
1012c19:dd:d9:dd:c25:c25b:d00a:c864/1282c19:dd:d9:dd:c25:c25b:d00a:c864
1022c19:dd:d9:dd:c25:c25b:d00a:c865/1282c19:dd:d9:dd:c25:c25b:d00a:c865
1032c19:dd:d9:dd:c25:c25b:d00a:c866/1282c19:dd:d9:dd:c25:c25b:d00a:c866
1042c19:dd:d9:dd:c25:c25b:d00a:c867/1282c19:dd:d9:dd:c25:c25b:d00a:c867
1052c19:dd:d9:dd:c25:c25b:d00a:c868/1282c19:dd:d9:dd:c25:c25b:d00a:c868
1062c19:dd:d9:dd:c25:c25b:d00a:c869/1282c19:dd:d9:dd:c25:c25b:d00a:c869
1072c19:dd:d9:dd:c25:c25b:d00a:c86a/1282c19:dd:d9:dd:c25:c25b:d00a:c86a
1082c19:dd:d9:dd:c25:c25b:d00a:c86b/1282c19:dd:d9:dd:c25:c25b:d00a:c86b
1092c19:dd:d9:dd:c25:c25b:d00a:c86c/1282c19:dd:d9:dd:c25:c25b:d00a:c86c
1102c19:dd:d9:dd:c25:c25b:d00a:c86d/1282c19:dd:d9:dd:c25:c25b:d00a:c86d
1112c19:dd:d9:dd:c25:c25b:d00a:c86e/1282c19:dd:d9:dd:c25:c25b:d00a:c86e
1122c19:dd:d9:dd:c25:c25b:d00a:c86f/1282c19:dd:d9:dd:c25:c25b:d00a:c86f
1132c19:dd:d9:dd:c25:c25b:d00a:c870/1282c19:dd:d9:dd:c25:c25b:d00a:c870
1142c19:dd:d9:dd:c25:c25b:d00a:c871/1282c19:dd:d9:dd:c25:c25b:d00a:c871
1152c19:dd:d9:dd:c25:c25b:d00a:c872/1282c19:dd:d9:dd:c25:c25b:d00a:c872
1162c19:dd:d9:dd:c25:c25b:d00a:c873/1282c19:dd:d9:dd:c25:c25b:d00a:c873
1172c19:dd:d9:dd:c25:c25b:d00a:c874/1282c19:dd:d9:dd:c25:c25b:d00a:c874
1182c19:dd:d9:dd:c25:c25b:d00a:c875/1282c19:dd:d9:dd:c25:c25b:d00a:c875
1192c19:dd:d9:dd:c25:c25b:d00a:c876/1282c19:dd:d9:dd:c25:c25b:d00a:c876
1202c19:dd:d9:dd:c25:c25b:d00a:c877/1282c19:dd:d9:dd:c25:c25b:d00a:c877
1212c19:dd:d9:dd:c25:c25b:d00a:c878/1282c19:dd:d9:dd:c25:c25b:d00a:c878
1222c19:dd:d9:dd:c25:c25b:d00a:c879/1282c19:dd:d9:dd:c25:c25b:d00a:c879
1232c19:dd:d9:dd:c25:c25b:d00a:c87a/1282c19:dd:d9:dd:c25:c25b:d00a:c87a
1242c19:dd:d9:dd:c25:c25b:d00a:c87b/1282c19:dd:d9:dd:c25:c25b:d00a:c87b
1252c19:dd:d9:dd:c25:c25b:d00a:c87c/1282c19:dd:d9:dd:c25:c25b:d00a:c87c
1262c19:dd:d9:dd:c25:c25b:d00a:c87d/1282c19:dd:d9:dd:c25:c25b:d00a:c87d
1272c19:dd:d9:dd:c25:c25b:d00a:c87e/1282c19:dd:d9:dd:c25:c25b:d00a:c87e
1282c19:dd:d9:dd:c25:c25b:d00a:c87f/1282c19:dd:d9:dd:c25:c25b:d00a:c87f
1292c19:dd:d9:dd:c25:c25b:d00a:c880/1282c19:dd:d9:dd:c25:c25b:d00a:c880
1302c19:dd:d9:dd:c25:c25b:d00a:c881/1282c19:dd:d9:dd:c25:c25b:d00a:c881
1312c19:dd:d9:dd:c25:c25b:d00a:c882/1282c19:dd:d9:dd:c25:c25b:d00a:c882
1322c19:dd:d9:dd:c25:c25b:d00a:c883/1282c19:dd:d9:dd:c25:c25b:d00a:c883
1332c19:dd:d9:dd:c25:c25b:d00a:c884/1282c19:dd:d9:dd:c25:c25b:d00a:c884
1342c19:dd:d9:dd:c25:c25b:d00a:c885/1282c19:dd:d9:dd:c25:c25b:d00a:c885
1352c19:dd:d9:dd:c25:c25b:d00a:c886/1282c19:dd:d9:dd:c25:c25b:d00a:c886
1362c19:dd:d9:dd:c25:c25b:d00a:c887/1282c19:dd:d9:dd:c25:c25b:d00a:c887
1372c19:dd:d9:dd:c25:c25b:d00a:c888/1282c19:dd:d9:dd:c25:c25b:d00a:c888
1382c19:dd:d9:dd:c25:c25b:d00a:c889/1282c19:dd:d9:dd:c25:c25b:d00a:c889
1392c19:dd:d9:dd:c25:c25b:d00a:c88a/1282c19:dd:d9:dd:c25:c25b:d00a:c88a
1402c19:dd:d9:dd:c25:c25b:d00a:c88b/1282c19:dd:d9:dd:c25:c25b:d00a:c88b
1412c19:dd:d9:dd:c25:c25b:d00a:c88c/1282c19:dd:d9:dd:c25:c25b:d00a:c88c
1422c19:dd:d9:dd:c25:c25b:d00a:c88d/1282c19:dd:d9:dd:c25:c25b:d00a:c88d
1432c19:dd:d9:dd:c25:c25b:d00a:c88e/1282c19:dd:d9:dd:c25:c25b:d00a:c88e
1442c19:dd:d9:dd:c25:c25b:d00a:c88f/1282c19:dd:d9:dd:c25:c25b:d00a:c88f
1452c19:dd:d9:dd:c25:c25b:d00a:c890/1282c19:dd:d9:dd:c25:c25b:d00a:c890
1462c19:dd:d9:dd:c25:c25b:d00a:c891/1282c19:dd:d9:dd:c25:c25b:d00a:c891
1472c19:dd:d9:dd:c25:c25b:d00a:c892/1282c19:dd:d9:dd:c25:c25b:d00a:c892
1482c19:dd:d9:dd:c25:c25b:d00a:c893/1282c19:dd:d9:dd:c25:c25b:d00a:c893
1492c19:dd:d9:dd:c25:c25b:d00a:c894/1282c19:dd:d9:dd:c25:c25b:d00a:c894
1502c19:dd:d9:dd:c25:c25b:d00a:c895/1282c19:dd:d9:dd:c25:c25b:d00a:c895
1512c19:dd:d9:dd:c25:c25b:d00a:c896/1282c19:dd:d9:dd:c25:c25b:d00a:c896
1522c19:dd:d9:dd:c25:c25b:d00a:c897/1282c19:dd:d9:dd:c25:c25b:d00a:c897
1532c19:dd:d9:dd:c25:c25b:d00a:c898/1282c19:dd:d9:dd:c25:c25b:d00a:c898
1542c19:dd:d9:dd:c25:c25b:d00a:c899/1282c19:dd:d9:dd:c25:c25b:d00a:c899
1552c19:dd:d9:dd:c25:c25b:d00a:c89a/1282c19:dd:d9:dd:c25:c25b:d00a:c89a
1562c19:dd:d9:dd:c25:c25b:d00a:c89b/1282c19:dd:d9:dd:c25:c25b:d00a:c89b
1572c19:dd:d9:dd:c25:c25b:d00a:c89c/1282c19:dd:d9:dd:c25:c25b:d00a:c89c
1582c19:dd:d9:dd:c25:c25b:d00a:c89d/1282c19:dd:d9:dd:c25:c25b:d00a:c89d
1592c19:dd:d9:dd:c25:c25b:d00a:c89e/1282c19:dd:d9:dd:c25:c25b:d00a:c89e
1602c19:dd:d9:dd:c25:c25b:d00a:c89f/1282c19:dd:d9:dd:c25:c25b:d00a:c89f
1612c19:dd:d9:dd:c25:c25b:d00a:c8a0/1282c19:dd:d9:dd:c25:c25b:d00a:c8a0
1622c19:dd:d9:dd:c25:c25b:d00a:c8a1/1282c19:dd:d9:dd:c25:c25b:d00a:c8a1
1632c19:dd:d9:dd:c25:c25b:d00a:c8a2/1282c19:dd:d9:dd:c25:c25b:d00a:c8a2
1642c19:dd:d9:dd:c25:c25b:d00a:c8a3/1282c19:dd:d9:dd:c25:c25b:d00a:c8a3
1652c19:dd:d9:dd:c25:c25b:d00a:c8a4/1282c19:dd:d9:dd:c25:c25b:d00a:c8a4
1662c19:dd:d9:dd:c25:c25b:d00a:c8a5/1282c19:dd:d9:dd:c25:c25b:d00a:c8a5
1672c19:dd:d9:dd:c25:c25b:d00a:c8a6/1282c19:dd:d9:dd:c25:c25b:d00a:c8a6
1682c19:dd:d9:dd:c25:c25b:d00a:c8a7/1282c19:dd:d9:dd:c25:c25b:d00a:c8a7
1692c19:dd:d9:dd:c25:c25b:d00a:c8a8/1282c19:dd:d9:dd:c25:c25b:d00a:c8a8
1702c19:dd:d9:dd:c25:c25b:d00a:c8a9/1282c19:dd:d9:dd:c25:c25b:d00a:c8a9
1712c19:dd:d9:dd:c25:c25b:d00a:c8aa/1282c19:dd:d9:dd:c25:c25b:d00a:c8aa
1722c19:dd:d9:dd:c25:c25b:d00a:c8ab/1282c19:dd:d9:dd:c25:c25b:d00a:c8ab
1732c19:dd:d9:dd:c25:c25b:d00a:c8ac/1282c19:dd:d9:dd:c25:c25b:d00a:c8ac
1742c19:dd:d9:dd:c25:c25b:d00a:c8ad/1282c19:dd:d9:dd:c25:c25b:d00a:c8ad
1752c19:dd:d9:dd:c25:c25b:d00a:c8ae/1282c19:dd:d9:dd:c25:c25b:d00a:c8ae
1762c19:dd:d9:dd:c25:c25b:d00a:c8af/1282c19:dd:d9:dd:c25:c25b:d00a:c8af
1772c19:dd:d9:dd:c25:c25b:d00a:c8b0/1282c19:dd:d9:dd:c25:c25b:d00a:c8b0
1782c19:dd:d9:dd:c25:c25b:d00a:c8b1/1282c19:dd:d9:dd:c25:c25b:d00a:c8b1
1792c19:dd:d9:dd:c25:c25b:d00a:c8b2/1282c19:dd:d9:dd:c25:c25b:d00a:c8b2
1802c19:dd:d9:dd:c25:c25b:d00a:c8b3/1282c19:dd:d9:dd:c25:c25b:d00a:c8b3
1812c19:dd:d9:dd:c25:c25b:d00a:c8b4/1282c19:dd:d9:dd:c25:c25b:d00a:c8b4
1822c19:dd:d9:dd:c25:c25b:d00a:c8b5/1282c19:dd:d9:dd:c25:c25b:d00a:c8b5
1832c19:dd:d9:dd:c25:c25b:d00a:c8b6/1282c19:dd:d9:dd:c25:c25b:d00a:c8b6
1842c19:dd:d9:dd:c25:c25b:d00a:c8b7/1282c19:dd:d9:dd:c25:c25b:d00a:c8b7
1852c19:dd:d9:dd:c25:c25b:d00a:c8b8/1282c19:dd:d9:dd:c25:c25b:d00a:c8b8
1862c19:dd:d9:dd:c25:c25b:d00a:c8b9/1282c19:dd:d9:dd:c25:c25b:d00a:c8b9
1872c19:dd:d9:dd:c25:c25b:d00a:c8ba/1282c19:dd:d9:dd:c25:c25b:d00a:c8ba
1882c19:dd:d9:dd:c25:c25b:d00a:c8bb/1282c19:dd:d9:dd:c25:c25b:d00a:c8bb
1892c19:dd:d9:dd:c25:c25b:d00a:c8bc/1282c19:dd:d9:dd:c25:c25b:d00a:c8bc
1902c19:dd:d9:dd:c25:c25b:d00a:c8bd/1282c19:dd:d9:dd:c25:c25b:d00a:c8bd
1912c19:dd:d9:dd:c25:c25b:d00a:c8be/1282c19:dd:d9:dd:c25:c25b:d00a:c8be
1922c19:dd:d9:dd:c25:c25b:d00a:c8bf/1282c19:dd:d9:dd:c25:c25b:d00a:c8bf
1932c19:dd:d9:dd:c25:c25b:d00a:c8c0/1282c19:dd:d9:dd:c25:c25b:d00a:c8c0
1942c19:dd:d9:dd:c25:c25b:d00a:c8c1/1282c19:dd:d9:dd:c25:c25b:d00a:c8c1
1952c19:dd:d9:dd:c25:c25b:d00a:c8c2/1282c19:dd:d9:dd:c25:c25b:d00a:c8c2
1962c19:dd:d9:dd:c25:c25b:d00a:c8c3/1282c19:dd:d9:dd:c25:c25b:d00a:c8c3
1972c19:dd:d9:dd:c25:c25b:d00a:c8c4/1282c19:dd:d9:dd:c25:c25b:d00a:c8c4
1982c19:dd:d9:dd:c25:c25b:d00a:c8c5/1282c19:dd:d9:dd:c25:c25b:d00a:c8c5
1992c19:dd:d9:dd:c25:c25b:d00a:c8c6/1282c19:dd:d9:dd:c25:c25b:d00a:c8c6
2002c19:dd:d9:dd:c25:c25b:d00a:c8c7/1282c19:dd:d9:dd:c25:c25b:d00a:c8c7
2012c19:dd:d9:dd:c25:c25b:d00a:c8c8/1282c19:dd:d9:dd:c25:c25b:d00a:c8c8
2022c19:dd:d9:dd:c25:c25b:d00a:c8c9/1282c19:dd:d9:dd:c25:c25b:d00a:c8c9
2032c19:dd:d9:dd:c25:c25b:d00a:c8ca/1282c19:dd:d9:dd:c25:c25b:d00a:c8ca
2042c19:dd:d9:dd:c25:c25b:d00a:c8cb/1282c19:dd:d9:dd:c25:c25b:d00a:c8cb
2052c19:dd:d9:dd:c25:c25b:d00a:c8cc/1282c19:dd:d9:dd:c25:c25b:d00a:c8cc
2062c19:dd:d9:dd:c25:c25b:d00a:c8cd/1282c19:dd:d9:dd:c25:c25b:d00a:c8cd
2072c19:dd:d9:dd:c25:c25b:d00a:c8ce/1282c19:dd:d9:dd:c25:c25b:d00a:c8ce
2082c19:dd:d9:dd:c25:c25b:d00a:c8cf/1282c19:dd:d9:dd:c25:c25b:d00a:c8cf
2092c19:dd:d9:dd:c25:c25b:d00a:c8d0/1282c19:dd:d9:dd:c25:c25b:d00a:c8d0
2102c19:dd:d9:dd:c25:c25b:d00a:c8d1/1282c19:dd:d9:dd:c25:c25b:d00a:c8d1
2112c19:dd:d9:dd:c25:c25b:d00a:c8d2/1282c19:dd:d9:dd:c25:c25b:d00a:c8d2
2122c19:dd:d9:dd:c25:c25b:d00a:c8d3/1282c19:dd:d9:dd:c25:c25b:d00a:c8d3
2132c19:dd:d9:dd:c25:c25b:d00a:c8d4/1282c19:dd:d9:dd:c25:c25b:d00a:c8d4
2142c19:dd:d9:dd:c25:c25b:d00a:c8d5/1282c19:dd:d9:dd:c25:c25b:d00a:c8d5
2152c19:dd:d9:dd:c25:c25b:d00a:c8d6/1282c19:dd:d9:dd:c25:c25b:d00a:c8d6
2162c19:dd:d9:dd:c25:c25b:d00a:c8d7/1282c19:dd:d9:dd:c25:c25b:d00a:c8d7
2172c19:dd:d9:dd:c25:c25b:d00a:c8d8/1282c19:dd:d9:dd:c25:c25b:d00a:c8d8
2182c19:dd:d9:dd:c25:c25b:d00a:c8d9/1282c19:dd:d9:dd:c25:c25b:d00a:c8d9
2192c19:dd:d9:dd:c25:c25b:d00a:c8da/1282c19:dd:d9:dd:c25:c25b:d00a:c8da
2202c19:dd:d9:dd:c25:c25b:d00a:c8db/1282c19:dd:d9:dd:c25:c25b:d00a:c8db
2212c19:dd:d9:dd:c25:c25b:d00a:c8dc/1282c19:dd:d9:dd:c25:c25b:d00a:c8dc
2222c19:dd:d9:dd:c25:c25b:d00a:c8dd/1282c19:dd:d9:dd:c25:c25b:d00a:c8dd
2232c19:dd:d9:dd:c25:c25b:d00a:c8de/1282c19:dd:d9:dd:c25:c25b:d00a:c8de
2242c19:dd:d9:dd:c25:c25b:d00a:c8df/1282c19:dd:d9:dd:c25:c25b:d00a:c8df
2252c19:dd:d9:dd:c25:c25b:d00a:c8e0/1282c19:dd:d9:dd:c25:c25b:d00a:c8e0
2262c19:dd:d9:dd:c25:c25b:d00a:c8e1/1282c19:dd:d9:dd:c25:c25b:d00a:c8e1
2272c19:dd:d9:dd:c25:c25b:d00a:c8e2/1282c19:dd:d9:dd:c25:c25b:d00a:c8e2
2282c19:dd:d9:dd:c25:c25b:d00a:c8e3/1282c19:dd:d9:dd:c25:c25b:d00a:c8e3
2292c19:dd:d9:dd:c25:c25b:d00a:c8e4/1282c19:dd:d9:dd:c25:c25b:d00a:c8e4
2302c19:dd:d9:dd:c25:c25b:d00a:c8e5/1282c19:dd:d9:dd:c25:c25b:d00a:c8e5
2312c19:dd:d9:dd:c25:c25b:d00a:c8e6/1282c19:dd:d9:dd:c25:c25b:d00a:c8e6
2322c19:dd:d9:dd:c25:c25b:d00a:c8e7/1282c19:dd:d9:dd:c25:c25b:d00a:c8e7
2332c19:dd:d9:dd:c25:c25b:d00a:c8e8/1282c19:dd:d9:dd:c25:c25b:d00a:c8e8
2342c19:dd:d9:dd:c25:c25b:d00a:c8e9/1282c19:dd:d9:dd:c25:c25b:d00a:c8e9
2352c19:dd:d9:dd:c25:c25b:d00a:c8ea/1282c19:dd:d9:dd:c25:c25b:d00a:c8ea
2362c19:dd:d9:dd:c25:c25b:d00a:c8eb/1282c19:dd:d9:dd:c25:c25b:d00a:c8eb
2372c19:dd:d9:dd:c25:c25b:d00a:c8ec/1282c19:dd:d9:dd:c25:c25b:d00a:c8ec
2382c19:dd:d9:dd:c25:c25b:d00a:c8ed/1282c19:dd:d9:dd:c25:c25b:d00a:c8ed
2392c19:dd:d9:dd:c25:c25b:d00a:c8ee/1282c19:dd:d9:dd:c25:c25b:d00a:c8ee
2402c19:dd:d9:dd:c25:c25b:d00a:c8ef/1282c19:dd:d9:dd:c25:c25b:d00a:c8ef
2412c19:dd:d9:dd:c25:c25b:d00a:c8f0/1282c19:dd:d9:dd:c25:c25b:d00a:c8f0
2422c19:dd:d9:dd:c25:c25b:d00a:c8f1/1282c19:dd:d9:dd:c25:c25b:d00a:c8f1
2432c19:dd:d9:dd:c25:c25b:d00a:c8f2/1282c19:dd:d9:dd:c25:c25b:d00a:c8f2
2442c19:dd:d9:dd:c25:c25b:d00a:c8f3/1282c19:dd:d9:dd:c25:c25b:d00a:c8f3
2452c19:dd:d9:dd:c25:c25b:d00a:c8f4/1282c19:dd:d9:dd:c25:c25b:d00a:c8f4
2462c19:dd:d9:dd:c25:c25b:d00a:c8f5/1282c19:dd:d9:dd:c25:c25b:d00a:c8f5
2472c19:dd:d9:dd:c25:c25b:d00a:c8f6/1282c19:dd:d9:dd:c25:c25b:d00a:c8f6
2482c19:dd:d9:dd:c25:c25b:d00a:c8f7/1282c19:dd:d9:dd:c25:c25b:d00a:c8f7
2492c19:dd:d9:dd:c25:c25b:d00a:c8f8/1282c19:dd:d9:dd:c25:c25b:d00a:c8f8
2502c19:dd:d9:dd:c25:c25b:d00a:c8f9/1282c19:dd:d9:dd:c25:c25b:d00a:c8f9
2512c19:dd:d9:dd:c25:c25b:d00a:c8fa/1282c19:dd:d9:dd:c25:c25b:d00a:c8fa
2522c19:dd:d9:dd:c25:c25b:d00a:c8fb/1282c19:dd:d9:dd:c25:c25b:d00a:c8fb
2532c19:dd:d9:dd:c25:c25b:d00a:c8fc/1282c19:dd:d9:dd:c25:c25b:d00a:c8fc
2542c19:dd:d9:dd:c25:c25b:d00a:c8fd/1282c19:dd:d9:dd:c25:c25b:d00a:c8fd
2552c19:dd:d9:dd:c25:c25b:d00a:c8fe/1282c19:dd:d9:dd:c25:c25b:d00a:c8fe
2562c19:dd:d9:dd:c25:c25b:d00a:c8ff/1282c19:dd:d9:dd:c25:c25b:d00a:c8ff

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.