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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:b800/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:b800
Last address
2c19:dd:d9:dd:c25:c25b:d00a:b8ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:b800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.b.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:b800/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:b800/1282c19:dd:d9:dd:c25:c25b:d00a:b800
22c19:dd:d9:dd:c25:c25b:d00a:b801/1282c19:dd:d9:dd:c25:c25b:d00a:b801
32c19:dd:d9:dd:c25:c25b:d00a:b802/1282c19:dd:d9:dd:c25:c25b:d00a:b802
42c19:dd:d9:dd:c25:c25b:d00a:b803/1282c19:dd:d9:dd:c25:c25b:d00a:b803
52c19:dd:d9:dd:c25:c25b:d00a:b804/1282c19:dd:d9:dd:c25:c25b:d00a:b804
62c19:dd:d9:dd:c25:c25b:d00a:b805/1282c19:dd:d9:dd:c25:c25b:d00a:b805
72c19:dd:d9:dd:c25:c25b:d00a:b806/1282c19:dd:d9:dd:c25:c25b:d00a:b806
82c19:dd:d9:dd:c25:c25b:d00a:b807/1282c19:dd:d9:dd:c25:c25b:d00a:b807
92c19:dd:d9:dd:c25:c25b:d00a:b808/1282c19:dd:d9:dd:c25:c25b:d00a:b808
102c19:dd:d9:dd:c25:c25b:d00a:b809/1282c19:dd:d9:dd:c25:c25b:d00a:b809
112c19:dd:d9:dd:c25:c25b:d00a:b80a/1282c19:dd:d9:dd:c25:c25b:d00a:b80a
122c19:dd:d9:dd:c25:c25b:d00a:b80b/1282c19:dd:d9:dd:c25:c25b:d00a:b80b
132c19:dd:d9:dd:c25:c25b:d00a:b80c/1282c19:dd:d9:dd:c25:c25b:d00a:b80c
142c19:dd:d9:dd:c25:c25b:d00a:b80d/1282c19:dd:d9:dd:c25:c25b:d00a:b80d
152c19:dd:d9:dd:c25:c25b:d00a:b80e/1282c19:dd:d9:dd:c25:c25b:d00a:b80e
162c19:dd:d9:dd:c25:c25b:d00a:b80f/1282c19:dd:d9:dd:c25:c25b:d00a:b80f
172c19:dd:d9:dd:c25:c25b:d00a:b810/1282c19:dd:d9:dd:c25:c25b:d00a:b810
182c19:dd:d9:dd:c25:c25b:d00a:b811/1282c19:dd:d9:dd:c25:c25b:d00a:b811
192c19:dd:d9:dd:c25:c25b:d00a:b812/1282c19:dd:d9:dd:c25:c25b:d00a:b812
202c19:dd:d9:dd:c25:c25b:d00a:b813/1282c19:dd:d9:dd:c25:c25b:d00a:b813
212c19:dd:d9:dd:c25:c25b:d00a:b814/1282c19:dd:d9:dd:c25:c25b:d00a:b814
222c19:dd:d9:dd:c25:c25b:d00a:b815/1282c19:dd:d9:dd:c25:c25b:d00a:b815
232c19:dd:d9:dd:c25:c25b:d00a:b816/1282c19:dd:d9:dd:c25:c25b:d00a:b816
242c19:dd:d9:dd:c25:c25b:d00a:b817/1282c19:dd:d9:dd:c25:c25b:d00a:b817
252c19:dd:d9:dd:c25:c25b:d00a:b818/1282c19:dd:d9:dd:c25:c25b:d00a:b818
262c19:dd:d9:dd:c25:c25b:d00a:b819/1282c19:dd:d9:dd:c25:c25b:d00a:b819
272c19:dd:d9:dd:c25:c25b:d00a:b81a/1282c19:dd:d9:dd:c25:c25b:d00a:b81a
282c19:dd:d9:dd:c25:c25b:d00a:b81b/1282c19:dd:d9:dd:c25:c25b:d00a:b81b
292c19:dd:d9:dd:c25:c25b:d00a:b81c/1282c19:dd:d9:dd:c25:c25b:d00a:b81c
302c19:dd:d9:dd:c25:c25b:d00a:b81d/1282c19:dd:d9:dd:c25:c25b:d00a:b81d
312c19:dd:d9:dd:c25:c25b:d00a:b81e/1282c19:dd:d9:dd:c25:c25b:d00a:b81e
322c19:dd:d9:dd:c25:c25b:d00a:b81f/1282c19:dd:d9:dd:c25:c25b:d00a:b81f
332c19:dd:d9:dd:c25:c25b:d00a:b820/1282c19:dd:d9:dd:c25:c25b:d00a:b820
342c19:dd:d9:dd:c25:c25b:d00a:b821/1282c19:dd:d9:dd:c25:c25b:d00a:b821
352c19:dd:d9:dd:c25:c25b:d00a:b822/1282c19:dd:d9:dd:c25:c25b:d00a:b822
362c19:dd:d9:dd:c25:c25b:d00a:b823/1282c19:dd:d9:dd:c25:c25b:d00a:b823
372c19:dd:d9:dd:c25:c25b:d00a:b824/1282c19:dd:d9:dd:c25:c25b:d00a:b824
382c19:dd:d9:dd:c25:c25b:d00a:b825/1282c19:dd:d9:dd:c25:c25b:d00a:b825
392c19:dd:d9:dd:c25:c25b:d00a:b826/1282c19:dd:d9:dd:c25:c25b:d00a:b826
402c19:dd:d9:dd:c25:c25b:d00a:b827/1282c19:dd:d9:dd:c25:c25b:d00a:b827
412c19:dd:d9:dd:c25:c25b:d00a:b828/1282c19:dd:d9:dd:c25:c25b:d00a:b828
422c19:dd:d9:dd:c25:c25b:d00a:b829/1282c19:dd:d9:dd:c25:c25b:d00a:b829
432c19:dd:d9:dd:c25:c25b:d00a:b82a/1282c19:dd:d9:dd:c25:c25b:d00a:b82a
442c19:dd:d9:dd:c25:c25b:d00a:b82b/1282c19:dd:d9:dd:c25:c25b:d00a:b82b
452c19:dd:d9:dd:c25:c25b:d00a:b82c/1282c19:dd:d9:dd:c25:c25b:d00a:b82c
462c19:dd:d9:dd:c25:c25b:d00a:b82d/1282c19:dd:d9:dd:c25:c25b:d00a:b82d
472c19:dd:d9:dd:c25:c25b:d00a:b82e/1282c19:dd:d9:dd:c25:c25b:d00a:b82e
482c19:dd:d9:dd:c25:c25b:d00a:b82f/1282c19:dd:d9:dd:c25:c25b:d00a:b82f
492c19:dd:d9:dd:c25:c25b:d00a:b830/1282c19:dd:d9:dd:c25:c25b:d00a:b830
502c19:dd:d9:dd:c25:c25b:d00a:b831/1282c19:dd:d9:dd:c25:c25b:d00a:b831
512c19:dd:d9:dd:c25:c25b:d00a:b832/1282c19:dd:d9:dd:c25:c25b:d00a:b832
522c19:dd:d9:dd:c25:c25b:d00a:b833/1282c19:dd:d9:dd:c25:c25b:d00a:b833
532c19:dd:d9:dd:c25:c25b:d00a:b834/1282c19:dd:d9:dd:c25:c25b:d00a:b834
542c19:dd:d9:dd:c25:c25b:d00a:b835/1282c19:dd:d9:dd:c25:c25b:d00a:b835
552c19:dd:d9:dd:c25:c25b:d00a:b836/1282c19:dd:d9:dd:c25:c25b:d00a:b836
562c19:dd:d9:dd:c25:c25b:d00a:b837/1282c19:dd:d9:dd:c25:c25b:d00a:b837
572c19:dd:d9:dd:c25:c25b:d00a:b838/1282c19:dd:d9:dd:c25:c25b:d00a:b838
582c19:dd:d9:dd:c25:c25b:d00a:b839/1282c19:dd:d9:dd:c25:c25b:d00a:b839
592c19:dd:d9:dd:c25:c25b:d00a:b83a/1282c19:dd:d9:dd:c25:c25b:d00a:b83a
602c19:dd:d9:dd:c25:c25b:d00a:b83b/1282c19:dd:d9:dd:c25:c25b:d00a:b83b
612c19:dd:d9:dd:c25:c25b:d00a:b83c/1282c19:dd:d9:dd:c25:c25b:d00a:b83c
622c19:dd:d9:dd:c25:c25b:d00a:b83d/1282c19:dd:d9:dd:c25:c25b:d00a:b83d
632c19:dd:d9:dd:c25:c25b:d00a:b83e/1282c19:dd:d9:dd:c25:c25b:d00a:b83e
642c19:dd:d9:dd:c25:c25b:d00a:b83f/1282c19:dd:d9:dd:c25:c25b:d00a:b83f
652c19:dd:d9:dd:c25:c25b:d00a:b840/1282c19:dd:d9:dd:c25:c25b:d00a:b840
662c19:dd:d9:dd:c25:c25b:d00a:b841/1282c19:dd:d9:dd:c25:c25b:d00a:b841
672c19:dd:d9:dd:c25:c25b:d00a:b842/1282c19:dd:d9:dd:c25:c25b:d00a:b842
682c19:dd:d9:dd:c25:c25b:d00a:b843/1282c19:dd:d9:dd:c25:c25b:d00a:b843
692c19:dd:d9:dd:c25:c25b:d00a:b844/1282c19:dd:d9:dd:c25:c25b:d00a:b844
702c19:dd:d9:dd:c25:c25b:d00a:b845/1282c19:dd:d9:dd:c25:c25b:d00a:b845
712c19:dd:d9:dd:c25:c25b:d00a:b846/1282c19:dd:d9:dd:c25:c25b:d00a:b846
722c19:dd:d9:dd:c25:c25b:d00a:b847/1282c19:dd:d9:dd:c25:c25b:d00a:b847
732c19:dd:d9:dd:c25:c25b:d00a:b848/1282c19:dd:d9:dd:c25:c25b:d00a:b848
742c19:dd:d9:dd:c25:c25b:d00a:b849/1282c19:dd:d9:dd:c25:c25b:d00a:b849
752c19:dd:d9:dd:c25:c25b:d00a:b84a/1282c19:dd:d9:dd:c25:c25b:d00a:b84a
762c19:dd:d9:dd:c25:c25b:d00a:b84b/1282c19:dd:d9:dd:c25:c25b:d00a:b84b
772c19:dd:d9:dd:c25:c25b:d00a:b84c/1282c19:dd:d9:dd:c25:c25b:d00a:b84c
782c19:dd:d9:dd:c25:c25b:d00a:b84d/1282c19:dd:d9:dd:c25:c25b:d00a:b84d
792c19:dd:d9:dd:c25:c25b:d00a:b84e/1282c19:dd:d9:dd:c25:c25b:d00a:b84e
802c19:dd:d9:dd:c25:c25b:d00a:b84f/1282c19:dd:d9:dd:c25:c25b:d00a:b84f
812c19:dd:d9:dd:c25:c25b:d00a:b850/1282c19:dd:d9:dd:c25:c25b:d00a:b850
822c19:dd:d9:dd:c25:c25b:d00a:b851/1282c19:dd:d9:dd:c25:c25b:d00a:b851
832c19:dd:d9:dd:c25:c25b:d00a:b852/1282c19:dd:d9:dd:c25:c25b:d00a:b852
842c19:dd:d9:dd:c25:c25b:d00a:b853/1282c19:dd:d9:dd:c25:c25b:d00a:b853
852c19:dd:d9:dd:c25:c25b:d00a:b854/1282c19:dd:d9:dd:c25:c25b:d00a:b854
862c19:dd:d9:dd:c25:c25b:d00a:b855/1282c19:dd:d9:dd:c25:c25b:d00a:b855
872c19:dd:d9:dd:c25:c25b:d00a:b856/1282c19:dd:d9:dd:c25:c25b:d00a:b856
882c19:dd:d9:dd:c25:c25b:d00a:b857/1282c19:dd:d9:dd:c25:c25b:d00a:b857
892c19:dd:d9:dd:c25:c25b:d00a:b858/1282c19:dd:d9:dd:c25:c25b:d00a:b858
902c19:dd:d9:dd:c25:c25b:d00a:b859/1282c19:dd:d9:dd:c25:c25b:d00a:b859
912c19:dd:d9:dd:c25:c25b:d00a:b85a/1282c19:dd:d9:dd:c25:c25b:d00a:b85a
922c19:dd:d9:dd:c25:c25b:d00a:b85b/1282c19:dd:d9:dd:c25:c25b:d00a:b85b
932c19:dd:d9:dd:c25:c25b:d00a:b85c/1282c19:dd:d9:dd:c25:c25b:d00a:b85c
942c19:dd:d9:dd:c25:c25b:d00a:b85d/1282c19:dd:d9:dd:c25:c25b:d00a:b85d
952c19:dd:d9:dd:c25:c25b:d00a:b85e/1282c19:dd:d9:dd:c25:c25b:d00a:b85e
962c19:dd:d9:dd:c25:c25b:d00a:b85f/1282c19:dd:d9:dd:c25:c25b:d00a:b85f
972c19:dd:d9:dd:c25:c25b:d00a:b860/1282c19:dd:d9:dd:c25:c25b:d00a:b860
982c19:dd:d9:dd:c25:c25b:d00a:b861/1282c19:dd:d9:dd:c25:c25b:d00a:b861
992c19:dd:d9:dd:c25:c25b:d00a:b862/1282c19:dd:d9:dd:c25:c25b:d00a:b862
1002c19:dd:d9:dd:c25:c25b:d00a:b863/1282c19:dd:d9:dd:c25:c25b:d00a:b863
1012c19:dd:d9:dd:c25:c25b:d00a:b864/1282c19:dd:d9:dd:c25:c25b:d00a:b864
1022c19:dd:d9:dd:c25:c25b:d00a:b865/1282c19:dd:d9:dd:c25:c25b:d00a:b865
1032c19:dd:d9:dd:c25:c25b:d00a:b866/1282c19:dd:d9:dd:c25:c25b:d00a:b866
1042c19:dd:d9:dd:c25:c25b:d00a:b867/1282c19:dd:d9:dd:c25:c25b:d00a:b867
1052c19:dd:d9:dd:c25:c25b:d00a:b868/1282c19:dd:d9:dd:c25:c25b:d00a:b868
1062c19:dd:d9:dd:c25:c25b:d00a:b869/1282c19:dd:d9:dd:c25:c25b:d00a:b869
1072c19:dd:d9:dd:c25:c25b:d00a:b86a/1282c19:dd:d9:dd:c25:c25b:d00a:b86a
1082c19:dd:d9:dd:c25:c25b:d00a:b86b/1282c19:dd:d9:dd:c25:c25b:d00a:b86b
1092c19:dd:d9:dd:c25:c25b:d00a:b86c/1282c19:dd:d9:dd:c25:c25b:d00a:b86c
1102c19:dd:d9:dd:c25:c25b:d00a:b86d/1282c19:dd:d9:dd:c25:c25b:d00a:b86d
1112c19:dd:d9:dd:c25:c25b:d00a:b86e/1282c19:dd:d9:dd:c25:c25b:d00a:b86e
1122c19:dd:d9:dd:c25:c25b:d00a:b86f/1282c19:dd:d9:dd:c25:c25b:d00a:b86f
1132c19:dd:d9:dd:c25:c25b:d00a:b870/1282c19:dd:d9:dd:c25:c25b:d00a:b870
1142c19:dd:d9:dd:c25:c25b:d00a:b871/1282c19:dd:d9:dd:c25:c25b:d00a:b871
1152c19:dd:d9:dd:c25:c25b:d00a:b872/1282c19:dd:d9:dd:c25:c25b:d00a:b872
1162c19:dd:d9:dd:c25:c25b:d00a:b873/1282c19:dd:d9:dd:c25:c25b:d00a:b873
1172c19:dd:d9:dd:c25:c25b:d00a:b874/1282c19:dd:d9:dd:c25:c25b:d00a:b874
1182c19:dd:d9:dd:c25:c25b:d00a:b875/1282c19:dd:d9:dd:c25:c25b:d00a:b875
1192c19:dd:d9:dd:c25:c25b:d00a:b876/1282c19:dd:d9:dd:c25:c25b:d00a:b876
1202c19:dd:d9:dd:c25:c25b:d00a:b877/1282c19:dd:d9:dd:c25:c25b:d00a:b877
1212c19:dd:d9:dd:c25:c25b:d00a:b878/1282c19:dd:d9:dd:c25:c25b:d00a:b878
1222c19:dd:d9:dd:c25:c25b:d00a:b879/1282c19:dd:d9:dd:c25:c25b:d00a:b879
1232c19:dd:d9:dd:c25:c25b:d00a:b87a/1282c19:dd:d9:dd:c25:c25b:d00a:b87a
1242c19:dd:d9:dd:c25:c25b:d00a:b87b/1282c19:dd:d9:dd:c25:c25b:d00a:b87b
1252c19:dd:d9:dd:c25:c25b:d00a:b87c/1282c19:dd:d9:dd:c25:c25b:d00a:b87c
1262c19:dd:d9:dd:c25:c25b:d00a:b87d/1282c19:dd:d9:dd:c25:c25b:d00a:b87d
1272c19:dd:d9:dd:c25:c25b:d00a:b87e/1282c19:dd:d9:dd:c25:c25b:d00a:b87e
1282c19:dd:d9:dd:c25:c25b:d00a:b87f/1282c19:dd:d9:dd:c25:c25b:d00a:b87f
1292c19:dd:d9:dd:c25:c25b:d00a:b880/1282c19:dd:d9:dd:c25:c25b:d00a:b880
1302c19:dd:d9:dd:c25:c25b:d00a:b881/1282c19:dd:d9:dd:c25:c25b:d00a:b881
1312c19:dd:d9:dd:c25:c25b:d00a:b882/1282c19:dd:d9:dd:c25:c25b:d00a:b882
1322c19:dd:d9:dd:c25:c25b:d00a:b883/1282c19:dd:d9:dd:c25:c25b:d00a:b883
1332c19:dd:d9:dd:c25:c25b:d00a:b884/1282c19:dd:d9:dd:c25:c25b:d00a:b884
1342c19:dd:d9:dd:c25:c25b:d00a:b885/1282c19:dd:d9:dd:c25:c25b:d00a:b885
1352c19:dd:d9:dd:c25:c25b:d00a:b886/1282c19:dd:d9:dd:c25:c25b:d00a:b886
1362c19:dd:d9:dd:c25:c25b:d00a:b887/1282c19:dd:d9:dd:c25:c25b:d00a:b887
1372c19:dd:d9:dd:c25:c25b:d00a:b888/1282c19:dd:d9:dd:c25:c25b:d00a:b888
1382c19:dd:d9:dd:c25:c25b:d00a:b889/1282c19:dd:d9:dd:c25:c25b:d00a:b889
1392c19:dd:d9:dd:c25:c25b:d00a:b88a/1282c19:dd:d9:dd:c25:c25b:d00a:b88a
1402c19:dd:d9:dd:c25:c25b:d00a:b88b/1282c19:dd:d9:dd:c25:c25b:d00a:b88b
1412c19:dd:d9:dd:c25:c25b:d00a:b88c/1282c19:dd:d9:dd:c25:c25b:d00a:b88c
1422c19:dd:d9:dd:c25:c25b:d00a:b88d/1282c19:dd:d9:dd:c25:c25b:d00a:b88d
1432c19:dd:d9:dd:c25:c25b:d00a:b88e/1282c19:dd:d9:dd:c25:c25b:d00a:b88e
1442c19:dd:d9:dd:c25:c25b:d00a:b88f/1282c19:dd:d9:dd:c25:c25b:d00a:b88f
1452c19:dd:d9:dd:c25:c25b:d00a:b890/1282c19:dd:d9:dd:c25:c25b:d00a:b890
1462c19:dd:d9:dd:c25:c25b:d00a:b891/1282c19:dd:d9:dd:c25:c25b:d00a:b891
1472c19:dd:d9:dd:c25:c25b:d00a:b892/1282c19:dd:d9:dd:c25:c25b:d00a:b892
1482c19:dd:d9:dd:c25:c25b:d00a:b893/1282c19:dd:d9:dd:c25:c25b:d00a:b893
1492c19:dd:d9:dd:c25:c25b:d00a:b894/1282c19:dd:d9:dd:c25:c25b:d00a:b894
1502c19:dd:d9:dd:c25:c25b:d00a:b895/1282c19:dd:d9:dd:c25:c25b:d00a:b895
1512c19:dd:d9:dd:c25:c25b:d00a:b896/1282c19:dd:d9:dd:c25:c25b:d00a:b896
1522c19:dd:d9:dd:c25:c25b:d00a:b897/1282c19:dd:d9:dd:c25:c25b:d00a:b897
1532c19:dd:d9:dd:c25:c25b:d00a:b898/1282c19:dd:d9:dd:c25:c25b:d00a:b898
1542c19:dd:d9:dd:c25:c25b:d00a:b899/1282c19:dd:d9:dd:c25:c25b:d00a:b899
1552c19:dd:d9:dd:c25:c25b:d00a:b89a/1282c19:dd:d9:dd:c25:c25b:d00a:b89a
1562c19:dd:d9:dd:c25:c25b:d00a:b89b/1282c19:dd:d9:dd:c25:c25b:d00a:b89b
1572c19:dd:d9:dd:c25:c25b:d00a:b89c/1282c19:dd:d9:dd:c25:c25b:d00a:b89c
1582c19:dd:d9:dd:c25:c25b:d00a:b89d/1282c19:dd:d9:dd:c25:c25b:d00a:b89d
1592c19:dd:d9:dd:c25:c25b:d00a:b89e/1282c19:dd:d9:dd:c25:c25b:d00a:b89e
1602c19:dd:d9:dd:c25:c25b:d00a:b89f/1282c19:dd:d9:dd:c25:c25b:d00a:b89f
1612c19:dd:d9:dd:c25:c25b:d00a:b8a0/1282c19:dd:d9:dd:c25:c25b:d00a:b8a0
1622c19:dd:d9:dd:c25:c25b:d00a:b8a1/1282c19:dd:d9:dd:c25:c25b:d00a:b8a1
1632c19:dd:d9:dd:c25:c25b:d00a:b8a2/1282c19:dd:d9:dd:c25:c25b:d00a:b8a2
1642c19:dd:d9:dd:c25:c25b:d00a:b8a3/1282c19:dd:d9:dd:c25:c25b:d00a:b8a3
1652c19:dd:d9:dd:c25:c25b:d00a:b8a4/1282c19:dd:d9:dd:c25:c25b:d00a:b8a4
1662c19:dd:d9:dd:c25:c25b:d00a:b8a5/1282c19:dd:d9:dd:c25:c25b:d00a:b8a5
1672c19:dd:d9:dd:c25:c25b:d00a:b8a6/1282c19:dd:d9:dd:c25:c25b:d00a:b8a6
1682c19:dd:d9:dd:c25:c25b:d00a:b8a7/1282c19:dd:d9:dd:c25:c25b:d00a:b8a7
1692c19:dd:d9:dd:c25:c25b:d00a:b8a8/1282c19:dd:d9:dd:c25:c25b:d00a:b8a8
1702c19:dd:d9:dd:c25:c25b:d00a:b8a9/1282c19:dd:d9:dd:c25:c25b:d00a:b8a9
1712c19:dd:d9:dd:c25:c25b:d00a:b8aa/1282c19:dd:d9:dd:c25:c25b:d00a:b8aa
1722c19:dd:d9:dd:c25:c25b:d00a:b8ab/1282c19:dd:d9:dd:c25:c25b:d00a:b8ab
1732c19:dd:d9:dd:c25:c25b:d00a:b8ac/1282c19:dd:d9:dd:c25:c25b:d00a:b8ac
1742c19:dd:d9:dd:c25:c25b:d00a:b8ad/1282c19:dd:d9:dd:c25:c25b:d00a:b8ad
1752c19:dd:d9:dd:c25:c25b:d00a:b8ae/1282c19:dd:d9:dd:c25:c25b:d00a:b8ae
1762c19:dd:d9:dd:c25:c25b:d00a:b8af/1282c19:dd:d9:dd:c25:c25b:d00a:b8af
1772c19:dd:d9:dd:c25:c25b:d00a:b8b0/1282c19:dd:d9:dd:c25:c25b:d00a:b8b0
1782c19:dd:d9:dd:c25:c25b:d00a:b8b1/1282c19:dd:d9:dd:c25:c25b:d00a:b8b1
1792c19:dd:d9:dd:c25:c25b:d00a:b8b2/1282c19:dd:d9:dd:c25:c25b:d00a:b8b2
1802c19:dd:d9:dd:c25:c25b:d00a:b8b3/1282c19:dd:d9:dd:c25:c25b:d00a:b8b3
1812c19:dd:d9:dd:c25:c25b:d00a:b8b4/1282c19:dd:d9:dd:c25:c25b:d00a:b8b4
1822c19:dd:d9:dd:c25:c25b:d00a:b8b5/1282c19:dd:d9:dd:c25:c25b:d00a:b8b5
1832c19:dd:d9:dd:c25:c25b:d00a:b8b6/1282c19:dd:d9:dd:c25:c25b:d00a:b8b6
1842c19:dd:d9:dd:c25:c25b:d00a:b8b7/1282c19:dd:d9:dd:c25:c25b:d00a:b8b7
1852c19:dd:d9:dd:c25:c25b:d00a:b8b8/1282c19:dd:d9:dd:c25:c25b:d00a:b8b8
1862c19:dd:d9:dd:c25:c25b:d00a:b8b9/1282c19:dd:d9:dd:c25:c25b:d00a:b8b9
1872c19:dd:d9:dd:c25:c25b:d00a:b8ba/1282c19:dd:d9:dd:c25:c25b:d00a:b8ba
1882c19:dd:d9:dd:c25:c25b:d00a:b8bb/1282c19:dd:d9:dd:c25:c25b:d00a:b8bb
1892c19:dd:d9:dd:c25:c25b:d00a:b8bc/1282c19:dd:d9:dd:c25:c25b:d00a:b8bc
1902c19:dd:d9:dd:c25:c25b:d00a:b8bd/1282c19:dd:d9:dd:c25:c25b:d00a:b8bd
1912c19:dd:d9:dd:c25:c25b:d00a:b8be/1282c19:dd:d9:dd:c25:c25b:d00a:b8be
1922c19:dd:d9:dd:c25:c25b:d00a:b8bf/1282c19:dd:d9:dd:c25:c25b:d00a:b8bf
1932c19:dd:d9:dd:c25:c25b:d00a:b8c0/1282c19:dd:d9:dd:c25:c25b:d00a:b8c0
1942c19:dd:d9:dd:c25:c25b:d00a:b8c1/1282c19:dd:d9:dd:c25:c25b:d00a:b8c1
1952c19:dd:d9:dd:c25:c25b:d00a:b8c2/1282c19:dd:d9:dd:c25:c25b:d00a:b8c2
1962c19:dd:d9:dd:c25:c25b:d00a:b8c3/1282c19:dd:d9:dd:c25:c25b:d00a:b8c3
1972c19:dd:d9:dd:c25:c25b:d00a:b8c4/1282c19:dd:d9:dd:c25:c25b:d00a:b8c4
1982c19:dd:d9:dd:c25:c25b:d00a:b8c5/1282c19:dd:d9:dd:c25:c25b:d00a:b8c5
1992c19:dd:d9:dd:c25:c25b:d00a:b8c6/1282c19:dd:d9:dd:c25:c25b:d00a:b8c6
2002c19:dd:d9:dd:c25:c25b:d00a:b8c7/1282c19:dd:d9:dd:c25:c25b:d00a:b8c7
2012c19:dd:d9:dd:c25:c25b:d00a:b8c8/1282c19:dd:d9:dd:c25:c25b:d00a:b8c8
2022c19:dd:d9:dd:c25:c25b:d00a:b8c9/1282c19:dd:d9:dd:c25:c25b:d00a:b8c9
2032c19:dd:d9:dd:c25:c25b:d00a:b8ca/1282c19:dd:d9:dd:c25:c25b:d00a:b8ca
2042c19:dd:d9:dd:c25:c25b:d00a:b8cb/1282c19:dd:d9:dd:c25:c25b:d00a:b8cb
2052c19:dd:d9:dd:c25:c25b:d00a:b8cc/1282c19:dd:d9:dd:c25:c25b:d00a:b8cc
2062c19:dd:d9:dd:c25:c25b:d00a:b8cd/1282c19:dd:d9:dd:c25:c25b:d00a:b8cd
2072c19:dd:d9:dd:c25:c25b:d00a:b8ce/1282c19:dd:d9:dd:c25:c25b:d00a:b8ce
2082c19:dd:d9:dd:c25:c25b:d00a:b8cf/1282c19:dd:d9:dd:c25:c25b:d00a:b8cf
2092c19:dd:d9:dd:c25:c25b:d00a:b8d0/1282c19:dd:d9:dd:c25:c25b:d00a:b8d0
2102c19:dd:d9:dd:c25:c25b:d00a:b8d1/1282c19:dd:d9:dd:c25:c25b:d00a:b8d1
2112c19:dd:d9:dd:c25:c25b:d00a:b8d2/1282c19:dd:d9:dd:c25:c25b:d00a:b8d2
2122c19:dd:d9:dd:c25:c25b:d00a:b8d3/1282c19:dd:d9:dd:c25:c25b:d00a:b8d3
2132c19:dd:d9:dd:c25:c25b:d00a:b8d4/1282c19:dd:d9:dd:c25:c25b:d00a:b8d4
2142c19:dd:d9:dd:c25:c25b:d00a:b8d5/1282c19:dd:d9:dd:c25:c25b:d00a:b8d5
2152c19:dd:d9:dd:c25:c25b:d00a:b8d6/1282c19:dd:d9:dd:c25:c25b:d00a:b8d6
2162c19:dd:d9:dd:c25:c25b:d00a:b8d7/1282c19:dd:d9:dd:c25:c25b:d00a:b8d7
2172c19:dd:d9:dd:c25:c25b:d00a:b8d8/1282c19:dd:d9:dd:c25:c25b:d00a:b8d8
2182c19:dd:d9:dd:c25:c25b:d00a:b8d9/1282c19:dd:d9:dd:c25:c25b:d00a:b8d9
2192c19:dd:d9:dd:c25:c25b:d00a:b8da/1282c19:dd:d9:dd:c25:c25b:d00a:b8da
2202c19:dd:d9:dd:c25:c25b:d00a:b8db/1282c19:dd:d9:dd:c25:c25b:d00a:b8db
2212c19:dd:d9:dd:c25:c25b:d00a:b8dc/1282c19:dd:d9:dd:c25:c25b:d00a:b8dc
2222c19:dd:d9:dd:c25:c25b:d00a:b8dd/1282c19:dd:d9:dd:c25:c25b:d00a:b8dd
2232c19:dd:d9:dd:c25:c25b:d00a:b8de/1282c19:dd:d9:dd:c25:c25b:d00a:b8de
2242c19:dd:d9:dd:c25:c25b:d00a:b8df/1282c19:dd:d9:dd:c25:c25b:d00a:b8df
2252c19:dd:d9:dd:c25:c25b:d00a:b8e0/1282c19:dd:d9:dd:c25:c25b:d00a:b8e0
2262c19:dd:d9:dd:c25:c25b:d00a:b8e1/1282c19:dd:d9:dd:c25:c25b:d00a:b8e1
2272c19:dd:d9:dd:c25:c25b:d00a:b8e2/1282c19:dd:d9:dd:c25:c25b:d00a:b8e2
2282c19:dd:d9:dd:c25:c25b:d00a:b8e3/1282c19:dd:d9:dd:c25:c25b:d00a:b8e3
2292c19:dd:d9:dd:c25:c25b:d00a:b8e4/1282c19:dd:d9:dd:c25:c25b:d00a:b8e4
2302c19:dd:d9:dd:c25:c25b:d00a:b8e5/1282c19:dd:d9:dd:c25:c25b:d00a:b8e5
2312c19:dd:d9:dd:c25:c25b:d00a:b8e6/1282c19:dd:d9:dd:c25:c25b:d00a:b8e6
2322c19:dd:d9:dd:c25:c25b:d00a:b8e7/1282c19:dd:d9:dd:c25:c25b:d00a:b8e7
2332c19:dd:d9:dd:c25:c25b:d00a:b8e8/1282c19:dd:d9:dd:c25:c25b:d00a:b8e8
2342c19:dd:d9:dd:c25:c25b:d00a:b8e9/1282c19:dd:d9:dd:c25:c25b:d00a:b8e9
2352c19:dd:d9:dd:c25:c25b:d00a:b8ea/1282c19:dd:d9:dd:c25:c25b:d00a:b8ea
2362c19:dd:d9:dd:c25:c25b:d00a:b8eb/1282c19:dd:d9:dd:c25:c25b:d00a:b8eb
2372c19:dd:d9:dd:c25:c25b:d00a:b8ec/1282c19:dd:d9:dd:c25:c25b:d00a:b8ec
2382c19:dd:d9:dd:c25:c25b:d00a:b8ed/1282c19:dd:d9:dd:c25:c25b:d00a:b8ed
2392c19:dd:d9:dd:c25:c25b:d00a:b8ee/1282c19:dd:d9:dd:c25:c25b:d00a:b8ee
2402c19:dd:d9:dd:c25:c25b:d00a:b8ef/1282c19:dd:d9:dd:c25:c25b:d00a:b8ef
2412c19:dd:d9:dd:c25:c25b:d00a:b8f0/1282c19:dd:d9:dd:c25:c25b:d00a:b8f0
2422c19:dd:d9:dd:c25:c25b:d00a:b8f1/1282c19:dd:d9:dd:c25:c25b:d00a:b8f1
2432c19:dd:d9:dd:c25:c25b:d00a:b8f2/1282c19:dd:d9:dd:c25:c25b:d00a:b8f2
2442c19:dd:d9:dd:c25:c25b:d00a:b8f3/1282c19:dd:d9:dd:c25:c25b:d00a:b8f3
2452c19:dd:d9:dd:c25:c25b:d00a:b8f4/1282c19:dd:d9:dd:c25:c25b:d00a:b8f4
2462c19:dd:d9:dd:c25:c25b:d00a:b8f5/1282c19:dd:d9:dd:c25:c25b:d00a:b8f5
2472c19:dd:d9:dd:c25:c25b:d00a:b8f6/1282c19:dd:d9:dd:c25:c25b:d00a:b8f6
2482c19:dd:d9:dd:c25:c25b:d00a:b8f7/1282c19:dd:d9:dd:c25:c25b:d00a:b8f7
2492c19:dd:d9:dd:c25:c25b:d00a:b8f8/1282c19:dd:d9:dd:c25:c25b:d00a:b8f8
2502c19:dd:d9:dd:c25:c25b:d00a:b8f9/1282c19:dd:d9:dd:c25:c25b:d00a:b8f9
2512c19:dd:d9:dd:c25:c25b:d00a:b8fa/1282c19:dd:d9:dd:c25:c25b:d00a:b8fa
2522c19:dd:d9:dd:c25:c25b:d00a:b8fb/1282c19:dd:d9:dd:c25:c25b:d00a:b8fb
2532c19:dd:d9:dd:c25:c25b:d00a:b8fc/1282c19:dd:d9:dd:c25:c25b:d00a:b8fc
2542c19:dd:d9:dd:c25:c25b:d00a:b8fd/1282c19:dd:d9:dd:c25:c25b:d00a:b8fd
2552c19:dd:d9:dd:c25:c25b:d00a:b8fe/1282c19:dd:d9:dd:c25:c25b:d00a:b8fe
2562c19:dd:d9:dd:c25:c25b:d00a:b8ff/1282c19:dd:d9:dd:c25:c25b:d00a:b8ff

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.