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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:c00a:d800/119
First address
2c19:dd:d9:dd:c25:c25:c00a:d800
Last address
2c19:dd:d9:dd:c25:c25:c00a:d9ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:c00a:d800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
8.d.a.0.0.c.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
9.d.a.0.0.c.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
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/128
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:c00a:d800/119 makes 512 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:c00a:d800/1282c19:dd:d9:dd:c25:c25:c00a:d800
22c19:dd:d9:dd:c25:c25:c00a:d801/1282c19:dd:d9:dd:c25:c25:c00a:d801
32c19:dd:d9:dd:c25:c25:c00a:d802/1282c19:dd:d9:dd:c25:c25:c00a:d802
42c19:dd:d9:dd:c25:c25:c00a:d803/1282c19:dd:d9:dd:c25:c25:c00a:d803
52c19:dd:d9:dd:c25:c25:c00a:d804/1282c19:dd:d9:dd:c25:c25:c00a:d804
62c19:dd:d9:dd:c25:c25:c00a:d805/1282c19:dd:d9:dd:c25:c25:c00a:d805
72c19:dd:d9:dd:c25:c25:c00a:d806/1282c19:dd:d9:dd:c25:c25:c00a:d806
82c19:dd:d9:dd:c25:c25:c00a:d807/1282c19:dd:d9:dd:c25:c25:c00a:d807
92c19:dd:d9:dd:c25:c25:c00a:d808/1282c19:dd:d9:dd:c25:c25:c00a:d808
102c19:dd:d9:dd:c25:c25:c00a:d809/1282c19:dd:d9:dd:c25:c25:c00a:d809
112c19:dd:d9:dd:c25:c25:c00a:d80a/1282c19:dd:d9:dd:c25:c25:c00a:d80a
122c19:dd:d9:dd:c25:c25:c00a:d80b/1282c19:dd:d9:dd:c25:c25:c00a:d80b
132c19:dd:d9:dd:c25:c25:c00a:d80c/1282c19:dd:d9:dd:c25:c25:c00a:d80c
142c19:dd:d9:dd:c25:c25:c00a:d80d/1282c19:dd:d9:dd:c25:c25:c00a:d80d
152c19:dd:d9:dd:c25:c25:c00a:d80e/1282c19:dd:d9:dd:c25:c25:c00a:d80e
162c19:dd:d9:dd:c25:c25:c00a:d80f/1282c19:dd:d9:dd:c25:c25:c00a:d80f
172c19:dd:d9:dd:c25:c25:c00a:d810/1282c19:dd:d9:dd:c25:c25:c00a:d810
182c19:dd:d9:dd:c25:c25:c00a:d811/1282c19:dd:d9:dd:c25:c25:c00a:d811
192c19:dd:d9:dd:c25:c25:c00a:d812/1282c19:dd:d9:dd:c25:c25:c00a:d812
202c19:dd:d9:dd:c25:c25:c00a:d813/1282c19:dd:d9:dd:c25:c25:c00a:d813
212c19:dd:d9:dd:c25:c25:c00a:d814/1282c19:dd:d9:dd:c25:c25:c00a:d814
222c19:dd:d9:dd:c25:c25:c00a:d815/1282c19:dd:d9:dd:c25:c25:c00a:d815
232c19:dd:d9:dd:c25:c25:c00a:d816/1282c19:dd:d9:dd:c25:c25:c00a:d816
242c19:dd:d9:dd:c25:c25:c00a:d817/1282c19:dd:d9:dd:c25:c25:c00a:d817
252c19:dd:d9:dd:c25:c25:c00a:d818/1282c19:dd:d9:dd:c25:c25:c00a:d818
262c19:dd:d9:dd:c25:c25:c00a:d819/1282c19:dd:d9:dd:c25:c25:c00a:d819
272c19:dd:d9:dd:c25:c25:c00a:d81a/1282c19:dd:d9:dd:c25:c25:c00a:d81a
282c19:dd:d9:dd:c25:c25:c00a:d81b/1282c19:dd:d9:dd:c25:c25:c00a:d81b
292c19:dd:d9:dd:c25:c25:c00a:d81c/1282c19:dd:d9:dd:c25:c25:c00a:d81c
302c19:dd:d9:dd:c25:c25:c00a:d81d/1282c19:dd:d9:dd:c25:c25:c00a:d81d
312c19:dd:d9:dd:c25:c25:c00a:d81e/1282c19:dd:d9:dd:c25:c25:c00a:d81e
322c19:dd:d9:dd:c25:c25:c00a:d81f/1282c19:dd:d9:dd:c25:c25:c00a:d81f
332c19:dd:d9:dd:c25:c25:c00a:d820/1282c19:dd:d9:dd:c25:c25:c00a:d820
342c19:dd:d9:dd:c25:c25:c00a:d821/1282c19:dd:d9:dd:c25:c25:c00a:d821
352c19:dd:d9:dd:c25:c25:c00a:d822/1282c19:dd:d9:dd:c25:c25:c00a:d822
362c19:dd:d9:dd:c25:c25:c00a:d823/1282c19:dd:d9:dd:c25:c25:c00a:d823
372c19:dd:d9:dd:c25:c25:c00a:d824/1282c19:dd:d9:dd:c25:c25:c00a:d824
382c19:dd:d9:dd:c25:c25:c00a:d825/1282c19:dd:d9:dd:c25:c25:c00a:d825
392c19:dd:d9:dd:c25:c25:c00a:d826/1282c19:dd:d9:dd:c25:c25:c00a:d826
402c19:dd:d9:dd:c25:c25:c00a:d827/1282c19:dd:d9:dd:c25:c25:c00a:d827
412c19:dd:d9:dd:c25:c25:c00a:d828/1282c19:dd:d9:dd:c25:c25:c00a:d828
422c19:dd:d9:dd:c25:c25:c00a:d829/1282c19:dd:d9:dd:c25:c25:c00a:d829
432c19:dd:d9:dd:c25:c25:c00a:d82a/1282c19:dd:d9:dd:c25:c25:c00a:d82a
442c19:dd:d9:dd:c25:c25:c00a:d82b/1282c19:dd:d9:dd:c25:c25:c00a:d82b
452c19:dd:d9:dd:c25:c25:c00a:d82c/1282c19:dd:d9:dd:c25:c25:c00a:d82c
462c19:dd:d9:dd:c25:c25:c00a:d82d/1282c19:dd:d9:dd:c25:c25:c00a:d82d
472c19:dd:d9:dd:c25:c25:c00a:d82e/1282c19:dd:d9:dd:c25:c25:c00a:d82e
482c19:dd:d9:dd:c25:c25:c00a:d82f/1282c19:dd:d9:dd:c25:c25:c00a:d82f
492c19:dd:d9:dd:c25:c25:c00a:d830/1282c19:dd:d9:dd:c25:c25:c00a:d830
502c19:dd:d9:dd:c25:c25:c00a:d831/1282c19:dd:d9:dd:c25:c25:c00a:d831
512c19:dd:d9:dd:c25:c25:c00a:d832/1282c19:dd:d9:dd:c25:c25:c00a:d832
522c19:dd:d9:dd:c25:c25:c00a:d833/1282c19:dd:d9:dd:c25:c25:c00a:d833
532c19:dd:d9:dd:c25:c25:c00a:d834/1282c19:dd:d9:dd:c25:c25:c00a:d834
542c19:dd:d9:dd:c25:c25:c00a:d835/1282c19:dd:d9:dd:c25:c25:c00a:d835
552c19:dd:d9:dd:c25:c25:c00a:d836/1282c19:dd:d9:dd:c25:c25:c00a:d836
562c19:dd:d9:dd:c25:c25:c00a:d837/1282c19:dd:d9:dd:c25:c25:c00a:d837
572c19:dd:d9:dd:c25:c25:c00a:d838/1282c19:dd:d9:dd:c25:c25:c00a:d838
582c19:dd:d9:dd:c25:c25:c00a:d839/1282c19:dd:d9:dd:c25:c25:c00a:d839
592c19:dd:d9:dd:c25:c25:c00a:d83a/1282c19:dd:d9:dd:c25:c25:c00a:d83a
602c19:dd:d9:dd:c25:c25:c00a:d83b/1282c19:dd:d9:dd:c25:c25:c00a:d83b
612c19:dd:d9:dd:c25:c25:c00a:d83c/1282c19:dd:d9:dd:c25:c25:c00a:d83c
622c19:dd:d9:dd:c25:c25:c00a:d83d/1282c19:dd:d9:dd:c25:c25:c00a:d83d
632c19:dd:d9:dd:c25:c25:c00a:d83e/1282c19:dd:d9:dd:c25:c25:c00a:d83e
642c19:dd:d9:dd:c25:c25:c00a:d83f/1282c19:dd:d9:dd:c25:c25:c00a:d83f
652c19:dd:d9:dd:c25:c25:c00a:d840/1282c19:dd:d9:dd:c25:c25:c00a:d840
662c19:dd:d9:dd:c25:c25:c00a:d841/1282c19:dd:d9:dd:c25:c25:c00a:d841
672c19:dd:d9:dd:c25:c25:c00a:d842/1282c19:dd:d9:dd:c25:c25:c00a:d842
682c19:dd:d9:dd:c25:c25:c00a:d843/1282c19:dd:d9:dd:c25:c25:c00a:d843
692c19:dd:d9:dd:c25:c25:c00a:d844/1282c19:dd:d9:dd:c25:c25:c00a:d844
702c19:dd:d9:dd:c25:c25:c00a:d845/1282c19:dd:d9:dd:c25:c25:c00a:d845
712c19:dd:d9:dd:c25:c25:c00a:d846/1282c19:dd:d9:dd:c25:c25:c00a:d846
722c19:dd:d9:dd:c25:c25:c00a:d847/1282c19:dd:d9:dd:c25:c25:c00a:d847
732c19:dd:d9:dd:c25:c25:c00a:d848/1282c19:dd:d9:dd:c25:c25:c00a:d848
742c19:dd:d9:dd:c25:c25:c00a:d849/1282c19:dd:d9:dd:c25:c25:c00a:d849
752c19:dd:d9:dd:c25:c25:c00a:d84a/1282c19:dd:d9:dd:c25:c25:c00a:d84a
762c19:dd:d9:dd:c25:c25:c00a:d84b/1282c19:dd:d9:dd:c25:c25:c00a:d84b
772c19:dd:d9:dd:c25:c25:c00a:d84c/1282c19:dd:d9:dd:c25:c25:c00a:d84c
782c19:dd:d9:dd:c25:c25:c00a:d84d/1282c19:dd:d9:dd:c25:c25:c00a:d84d
792c19:dd:d9:dd:c25:c25:c00a:d84e/1282c19:dd:d9:dd:c25:c25:c00a:d84e
802c19:dd:d9:dd:c25:c25:c00a:d84f/1282c19:dd:d9:dd:c25:c25:c00a:d84f
812c19:dd:d9:dd:c25:c25:c00a:d850/1282c19:dd:d9:dd:c25:c25:c00a:d850
822c19:dd:d9:dd:c25:c25:c00a:d851/1282c19:dd:d9:dd:c25:c25:c00a:d851
832c19:dd:d9:dd:c25:c25:c00a:d852/1282c19:dd:d9:dd:c25:c25:c00a:d852
842c19:dd:d9:dd:c25:c25:c00a:d853/1282c19:dd:d9:dd:c25:c25:c00a:d853
852c19:dd:d9:dd:c25:c25:c00a:d854/1282c19:dd:d9:dd:c25:c25:c00a:d854
862c19:dd:d9:dd:c25:c25:c00a:d855/1282c19:dd:d9:dd:c25:c25:c00a:d855
872c19:dd:d9:dd:c25:c25:c00a:d856/1282c19:dd:d9:dd:c25:c25:c00a:d856
882c19:dd:d9:dd:c25:c25:c00a:d857/1282c19:dd:d9:dd:c25:c25:c00a:d857
892c19:dd:d9:dd:c25:c25:c00a:d858/1282c19:dd:d9:dd:c25:c25:c00a:d858
902c19:dd:d9:dd:c25:c25:c00a:d859/1282c19:dd:d9:dd:c25:c25:c00a:d859
912c19:dd:d9:dd:c25:c25:c00a:d85a/1282c19:dd:d9:dd:c25:c25:c00a:d85a
922c19:dd:d9:dd:c25:c25:c00a:d85b/1282c19:dd:d9:dd:c25:c25:c00a:d85b
932c19:dd:d9:dd:c25:c25:c00a:d85c/1282c19:dd:d9:dd:c25:c25:c00a:d85c
942c19:dd:d9:dd:c25:c25:c00a:d85d/1282c19:dd:d9:dd:c25:c25:c00a:d85d
952c19:dd:d9:dd:c25:c25:c00a:d85e/1282c19:dd:d9:dd:c25:c25:c00a:d85e
962c19:dd:d9:dd:c25:c25:c00a:d85f/1282c19:dd:d9:dd:c25:c25:c00a:d85f
972c19:dd:d9:dd:c25:c25:c00a:d860/1282c19:dd:d9:dd:c25:c25:c00a:d860
982c19:dd:d9:dd:c25:c25:c00a:d861/1282c19:dd:d9:dd:c25:c25:c00a:d861
992c19:dd:d9:dd:c25:c25:c00a:d862/1282c19:dd:d9:dd:c25:c25:c00a:d862
1002c19:dd:d9:dd:c25:c25:c00a:d863/1282c19:dd:d9:dd:c25:c25:c00a:d863
1012c19:dd:d9:dd:c25:c25:c00a:d864/1282c19:dd:d9:dd:c25:c25:c00a:d864
1022c19:dd:d9:dd:c25:c25:c00a:d865/1282c19:dd:d9:dd:c25:c25:c00a:d865
1032c19:dd:d9:dd:c25:c25:c00a:d866/1282c19:dd:d9:dd:c25:c25:c00a:d866
1042c19:dd:d9:dd:c25:c25:c00a:d867/1282c19:dd:d9:dd:c25:c25:c00a:d867
1052c19:dd:d9:dd:c25:c25:c00a:d868/1282c19:dd:d9:dd:c25:c25:c00a:d868
1062c19:dd:d9:dd:c25:c25:c00a:d869/1282c19:dd:d9:dd:c25:c25:c00a:d869
1072c19:dd:d9:dd:c25:c25:c00a:d86a/1282c19:dd:d9:dd:c25:c25:c00a:d86a
1082c19:dd:d9:dd:c25:c25:c00a:d86b/1282c19:dd:d9:dd:c25:c25:c00a:d86b
1092c19:dd:d9:dd:c25:c25:c00a:d86c/1282c19:dd:d9:dd:c25:c25:c00a:d86c
1102c19:dd:d9:dd:c25:c25:c00a:d86d/1282c19:dd:d9:dd:c25:c25:c00a:d86d
1112c19:dd:d9:dd:c25:c25:c00a:d86e/1282c19:dd:d9:dd:c25:c25:c00a:d86e
1122c19:dd:d9:dd:c25:c25:c00a:d86f/1282c19:dd:d9:dd:c25:c25:c00a:d86f
1132c19:dd:d9:dd:c25:c25:c00a:d870/1282c19:dd:d9:dd:c25:c25:c00a:d870
1142c19:dd:d9:dd:c25:c25:c00a:d871/1282c19:dd:d9:dd:c25:c25:c00a:d871
1152c19:dd:d9:dd:c25:c25:c00a:d872/1282c19:dd:d9:dd:c25:c25:c00a:d872
1162c19:dd:d9:dd:c25:c25:c00a:d873/1282c19:dd:d9:dd:c25:c25:c00a:d873
1172c19:dd:d9:dd:c25:c25:c00a:d874/1282c19:dd:d9:dd:c25:c25:c00a:d874
1182c19:dd:d9:dd:c25:c25:c00a:d875/1282c19:dd:d9:dd:c25:c25:c00a:d875
1192c19:dd:d9:dd:c25:c25:c00a:d876/1282c19:dd:d9:dd:c25:c25:c00a:d876
1202c19:dd:d9:dd:c25:c25:c00a:d877/1282c19:dd:d9:dd:c25:c25:c00a:d877
1212c19:dd:d9:dd:c25:c25:c00a:d878/1282c19:dd:d9:dd:c25:c25:c00a:d878
1222c19:dd:d9:dd:c25:c25:c00a:d879/1282c19:dd:d9:dd:c25:c25:c00a:d879
1232c19:dd:d9:dd:c25:c25:c00a:d87a/1282c19:dd:d9:dd:c25:c25:c00a:d87a
1242c19:dd:d9:dd:c25:c25:c00a:d87b/1282c19:dd:d9:dd:c25:c25:c00a:d87b
1252c19:dd:d9:dd:c25:c25:c00a:d87c/1282c19:dd:d9:dd:c25:c25:c00a:d87c
1262c19:dd:d9:dd:c25:c25:c00a:d87d/1282c19:dd:d9:dd:c25:c25:c00a:d87d
1272c19:dd:d9:dd:c25:c25:c00a:d87e/1282c19:dd:d9:dd:c25:c25:c00a:d87e
1282c19:dd:d9:dd:c25:c25:c00a:d87f/1282c19:dd:d9:dd:c25:c25:c00a:d87f
1292c19:dd:d9:dd:c25:c25:c00a:d880/1282c19:dd:d9:dd:c25:c25:c00a:d880
1302c19:dd:d9:dd:c25:c25:c00a:d881/1282c19:dd:d9:dd:c25:c25:c00a:d881
1312c19:dd:d9:dd:c25:c25:c00a:d882/1282c19:dd:d9:dd:c25:c25:c00a:d882
1322c19:dd:d9:dd:c25:c25:c00a:d883/1282c19:dd:d9:dd:c25:c25:c00a:d883
1332c19:dd:d9:dd:c25:c25:c00a:d884/1282c19:dd:d9:dd:c25:c25:c00a:d884
1342c19:dd:d9:dd:c25:c25:c00a:d885/1282c19:dd:d9:dd:c25:c25:c00a:d885
1352c19:dd:d9:dd:c25:c25:c00a:d886/1282c19:dd:d9:dd:c25:c25:c00a:d886
1362c19:dd:d9:dd:c25:c25:c00a:d887/1282c19:dd:d9:dd:c25:c25:c00a:d887
1372c19:dd:d9:dd:c25:c25:c00a:d888/1282c19:dd:d9:dd:c25:c25:c00a:d888
1382c19:dd:d9:dd:c25:c25:c00a:d889/1282c19:dd:d9:dd:c25:c25:c00a:d889
1392c19:dd:d9:dd:c25:c25:c00a:d88a/1282c19:dd:d9:dd:c25:c25:c00a:d88a
1402c19:dd:d9:dd:c25:c25:c00a:d88b/1282c19:dd:d9:dd:c25:c25:c00a:d88b
1412c19:dd:d9:dd:c25:c25:c00a:d88c/1282c19:dd:d9:dd:c25:c25:c00a:d88c
1422c19:dd:d9:dd:c25:c25:c00a:d88d/1282c19:dd:d9:dd:c25:c25:c00a:d88d
1432c19:dd:d9:dd:c25:c25:c00a:d88e/1282c19:dd:d9:dd:c25:c25:c00a:d88e
1442c19:dd:d9:dd:c25:c25:c00a:d88f/1282c19:dd:d9:dd:c25:c25:c00a:d88f
1452c19:dd:d9:dd:c25:c25:c00a:d890/1282c19:dd:d9:dd:c25:c25:c00a:d890
1462c19:dd:d9:dd:c25:c25:c00a:d891/1282c19:dd:d9:dd:c25:c25:c00a:d891
1472c19:dd:d9:dd:c25:c25:c00a:d892/1282c19:dd:d9:dd:c25:c25:c00a:d892
1482c19:dd:d9:dd:c25:c25:c00a:d893/1282c19:dd:d9:dd:c25:c25:c00a:d893
1492c19:dd:d9:dd:c25:c25:c00a:d894/1282c19:dd:d9:dd:c25:c25:c00a:d894
1502c19:dd:d9:dd:c25:c25:c00a:d895/1282c19:dd:d9:dd:c25:c25:c00a:d895
1512c19:dd:d9:dd:c25:c25:c00a:d896/1282c19:dd:d9:dd:c25:c25:c00a:d896
1522c19:dd:d9:dd:c25:c25:c00a:d897/1282c19:dd:d9:dd:c25:c25:c00a:d897
1532c19:dd:d9:dd:c25:c25:c00a:d898/1282c19:dd:d9:dd:c25:c25:c00a:d898
1542c19:dd:d9:dd:c25:c25:c00a:d899/1282c19:dd:d9:dd:c25:c25:c00a:d899
1552c19:dd:d9:dd:c25:c25:c00a:d89a/1282c19:dd:d9:dd:c25:c25:c00a:d89a
1562c19:dd:d9:dd:c25:c25:c00a:d89b/1282c19:dd:d9:dd:c25:c25:c00a:d89b
1572c19:dd:d9:dd:c25:c25:c00a:d89c/1282c19:dd:d9:dd:c25:c25:c00a:d89c
1582c19:dd:d9:dd:c25:c25:c00a:d89d/1282c19:dd:d9:dd:c25:c25:c00a:d89d
1592c19:dd:d9:dd:c25:c25:c00a:d89e/1282c19:dd:d9:dd:c25:c25:c00a:d89e
1602c19:dd:d9:dd:c25:c25:c00a:d89f/1282c19:dd:d9:dd:c25:c25:c00a:d89f
1612c19:dd:d9:dd:c25:c25:c00a:d8a0/1282c19:dd:d9:dd:c25:c25:c00a:d8a0
1622c19:dd:d9:dd:c25:c25:c00a:d8a1/1282c19:dd:d9:dd:c25:c25:c00a:d8a1
1632c19:dd:d9:dd:c25:c25:c00a:d8a2/1282c19:dd:d9:dd:c25:c25:c00a:d8a2
1642c19:dd:d9:dd:c25:c25:c00a:d8a3/1282c19:dd:d9:dd:c25:c25:c00a:d8a3
1652c19:dd:d9:dd:c25:c25:c00a:d8a4/1282c19:dd:d9:dd:c25:c25:c00a:d8a4
1662c19:dd:d9:dd:c25:c25:c00a:d8a5/1282c19:dd:d9:dd:c25:c25:c00a:d8a5
1672c19:dd:d9:dd:c25:c25:c00a:d8a6/1282c19:dd:d9:dd:c25:c25:c00a:d8a6
1682c19:dd:d9:dd:c25:c25:c00a:d8a7/1282c19:dd:d9:dd:c25:c25:c00a:d8a7
1692c19:dd:d9:dd:c25:c25:c00a:d8a8/1282c19:dd:d9:dd:c25:c25:c00a:d8a8
1702c19:dd:d9:dd:c25:c25:c00a:d8a9/1282c19:dd:d9:dd:c25:c25:c00a:d8a9
1712c19:dd:d9:dd:c25:c25:c00a:d8aa/1282c19:dd:d9:dd:c25:c25:c00a:d8aa
1722c19:dd:d9:dd:c25:c25:c00a:d8ab/1282c19:dd:d9:dd:c25:c25:c00a:d8ab
1732c19:dd:d9:dd:c25:c25:c00a:d8ac/1282c19:dd:d9:dd:c25:c25:c00a:d8ac
1742c19:dd:d9:dd:c25:c25:c00a:d8ad/1282c19:dd:d9:dd:c25:c25:c00a:d8ad
1752c19:dd:d9:dd:c25:c25:c00a:d8ae/1282c19:dd:d9:dd:c25:c25:c00a:d8ae
1762c19:dd:d9:dd:c25:c25:c00a:d8af/1282c19:dd:d9:dd:c25:c25:c00a:d8af
1772c19:dd:d9:dd:c25:c25:c00a:d8b0/1282c19:dd:d9:dd:c25:c25:c00a:d8b0
1782c19:dd:d9:dd:c25:c25:c00a:d8b1/1282c19:dd:d9:dd:c25:c25:c00a:d8b1
1792c19:dd:d9:dd:c25:c25:c00a:d8b2/1282c19:dd:d9:dd:c25:c25:c00a:d8b2
1802c19:dd:d9:dd:c25:c25:c00a:d8b3/1282c19:dd:d9:dd:c25:c25:c00a:d8b3
1812c19:dd:d9:dd:c25:c25:c00a:d8b4/1282c19:dd:d9:dd:c25:c25:c00a:d8b4
1822c19:dd:d9:dd:c25:c25:c00a:d8b5/1282c19:dd:d9:dd:c25:c25:c00a:d8b5
1832c19:dd:d9:dd:c25:c25:c00a:d8b6/1282c19:dd:d9:dd:c25:c25:c00a:d8b6
1842c19:dd:d9:dd:c25:c25:c00a:d8b7/1282c19:dd:d9:dd:c25:c25:c00a:d8b7
1852c19:dd:d9:dd:c25:c25:c00a:d8b8/1282c19:dd:d9:dd:c25:c25:c00a:d8b8
1862c19:dd:d9:dd:c25:c25:c00a:d8b9/1282c19:dd:d9:dd:c25:c25:c00a:d8b9
1872c19:dd:d9:dd:c25:c25:c00a:d8ba/1282c19:dd:d9:dd:c25:c25:c00a:d8ba
1882c19:dd:d9:dd:c25:c25:c00a:d8bb/1282c19:dd:d9:dd:c25:c25:c00a:d8bb
1892c19:dd:d9:dd:c25:c25:c00a:d8bc/1282c19:dd:d9:dd:c25:c25:c00a:d8bc
1902c19:dd:d9:dd:c25:c25:c00a:d8bd/1282c19:dd:d9:dd:c25:c25:c00a:d8bd
1912c19:dd:d9:dd:c25:c25:c00a:d8be/1282c19:dd:d9:dd:c25:c25:c00a:d8be
1922c19:dd:d9:dd:c25:c25:c00a:d8bf/1282c19:dd:d9:dd:c25:c25:c00a:d8bf
1932c19:dd:d9:dd:c25:c25:c00a:d8c0/1282c19:dd:d9:dd:c25:c25:c00a:d8c0
1942c19:dd:d9:dd:c25:c25:c00a:d8c1/1282c19:dd:d9:dd:c25:c25:c00a:d8c1
1952c19:dd:d9:dd:c25:c25:c00a:d8c2/1282c19:dd:d9:dd:c25:c25:c00a:d8c2
1962c19:dd:d9:dd:c25:c25:c00a:d8c3/1282c19:dd:d9:dd:c25:c25:c00a:d8c3
1972c19:dd:d9:dd:c25:c25:c00a:d8c4/1282c19:dd:d9:dd:c25:c25:c00a:d8c4
1982c19:dd:d9:dd:c25:c25:c00a:d8c5/1282c19:dd:d9:dd:c25:c25:c00a:d8c5
1992c19:dd:d9:dd:c25:c25:c00a:d8c6/1282c19:dd:d9:dd:c25:c25:c00a:d8c6
2002c19:dd:d9:dd:c25:c25:c00a:d8c7/1282c19:dd:d9:dd:c25:c25:c00a:d8c7
2012c19:dd:d9:dd:c25:c25:c00a:d8c8/1282c19:dd:d9:dd:c25:c25:c00a:d8c8
2022c19:dd:d9:dd:c25:c25:c00a:d8c9/1282c19:dd:d9:dd:c25:c25:c00a:d8c9
2032c19:dd:d9:dd:c25:c25:c00a:d8ca/1282c19:dd:d9:dd:c25:c25:c00a:d8ca
2042c19:dd:d9:dd:c25:c25:c00a:d8cb/1282c19:dd:d9:dd:c25:c25:c00a:d8cb
2052c19:dd:d9:dd:c25:c25:c00a:d8cc/1282c19:dd:d9:dd:c25:c25:c00a:d8cc
2062c19:dd:d9:dd:c25:c25:c00a:d8cd/1282c19:dd:d9:dd:c25:c25:c00a:d8cd
2072c19:dd:d9:dd:c25:c25:c00a:d8ce/1282c19:dd:d9:dd:c25:c25:c00a:d8ce
2082c19:dd:d9:dd:c25:c25:c00a:d8cf/1282c19:dd:d9:dd:c25:c25:c00a:d8cf
2092c19:dd:d9:dd:c25:c25:c00a:d8d0/1282c19:dd:d9:dd:c25:c25:c00a:d8d0
2102c19:dd:d9:dd:c25:c25:c00a:d8d1/1282c19:dd:d9:dd:c25:c25:c00a:d8d1
2112c19:dd:d9:dd:c25:c25:c00a:d8d2/1282c19:dd:d9:dd:c25:c25:c00a:d8d2
2122c19:dd:d9:dd:c25:c25:c00a:d8d3/1282c19:dd:d9:dd:c25:c25:c00a:d8d3
2132c19:dd:d9:dd:c25:c25:c00a:d8d4/1282c19:dd:d9:dd:c25:c25:c00a:d8d4
2142c19:dd:d9:dd:c25:c25:c00a:d8d5/1282c19:dd:d9:dd:c25:c25:c00a:d8d5
2152c19:dd:d9:dd:c25:c25:c00a:d8d6/1282c19:dd:d9:dd:c25:c25:c00a:d8d6
2162c19:dd:d9:dd:c25:c25:c00a:d8d7/1282c19:dd:d9:dd:c25:c25:c00a:d8d7
2172c19:dd:d9:dd:c25:c25:c00a:d8d8/1282c19:dd:d9:dd:c25:c25:c00a:d8d8
2182c19:dd:d9:dd:c25:c25:c00a:d8d9/1282c19:dd:d9:dd:c25:c25:c00a:d8d9
2192c19:dd:d9:dd:c25:c25:c00a:d8da/1282c19:dd:d9:dd:c25:c25:c00a:d8da
2202c19:dd:d9:dd:c25:c25:c00a:d8db/1282c19:dd:d9:dd:c25:c25:c00a:d8db
2212c19:dd:d9:dd:c25:c25:c00a:d8dc/1282c19:dd:d9:dd:c25:c25:c00a:d8dc
2222c19:dd:d9:dd:c25:c25:c00a:d8dd/1282c19:dd:d9:dd:c25:c25:c00a:d8dd
2232c19:dd:d9:dd:c25:c25:c00a:d8de/1282c19:dd:d9:dd:c25:c25:c00a:d8de
2242c19:dd:d9:dd:c25:c25:c00a:d8df/1282c19:dd:d9:dd:c25:c25:c00a:d8df
2252c19:dd:d9:dd:c25:c25:c00a:d8e0/1282c19:dd:d9:dd:c25:c25:c00a:d8e0
2262c19:dd:d9:dd:c25:c25:c00a:d8e1/1282c19:dd:d9:dd:c25:c25:c00a:d8e1
2272c19:dd:d9:dd:c25:c25:c00a:d8e2/1282c19:dd:d9:dd:c25:c25:c00a:d8e2
2282c19:dd:d9:dd:c25:c25:c00a:d8e3/1282c19:dd:d9:dd:c25:c25:c00a:d8e3
2292c19:dd:d9:dd:c25:c25:c00a:d8e4/1282c19:dd:d9:dd:c25:c25:c00a:d8e4
2302c19:dd:d9:dd:c25:c25:c00a:d8e5/1282c19:dd:d9:dd:c25:c25:c00a:d8e5
2312c19:dd:d9:dd:c25:c25:c00a:d8e6/1282c19:dd:d9:dd:c25:c25:c00a:d8e6
2322c19:dd:d9:dd:c25:c25:c00a:d8e7/1282c19:dd:d9:dd:c25:c25:c00a:d8e7
2332c19:dd:d9:dd:c25:c25:c00a:d8e8/1282c19:dd:d9:dd:c25:c25:c00a:d8e8
2342c19:dd:d9:dd:c25:c25:c00a:d8e9/1282c19:dd:d9:dd:c25:c25:c00a:d8e9
2352c19:dd:d9:dd:c25:c25:c00a:d8ea/1282c19:dd:d9:dd:c25:c25:c00a:d8ea
2362c19:dd:d9:dd:c25:c25:c00a:d8eb/1282c19:dd:d9:dd:c25:c25:c00a:d8eb
2372c19:dd:d9:dd:c25:c25:c00a:d8ec/1282c19:dd:d9:dd:c25:c25:c00a:d8ec
2382c19:dd:d9:dd:c25:c25:c00a:d8ed/1282c19:dd:d9:dd:c25:c25:c00a:d8ed
2392c19:dd:d9:dd:c25:c25:c00a:d8ee/1282c19:dd:d9:dd:c25:c25:c00a:d8ee
2402c19:dd:d9:dd:c25:c25:c00a:d8ef/1282c19:dd:d9:dd:c25:c25:c00a:d8ef
2412c19:dd:d9:dd:c25:c25:c00a:d8f0/1282c19:dd:d9:dd:c25:c25:c00a:d8f0
2422c19:dd:d9:dd:c25:c25:c00a:d8f1/1282c19:dd:d9:dd:c25:c25:c00a:d8f1
2432c19:dd:d9:dd:c25:c25:c00a:d8f2/1282c19:dd:d9:dd:c25:c25:c00a:d8f2
2442c19:dd:d9:dd:c25:c25:c00a:d8f3/1282c19:dd:d9:dd:c25:c25:c00a:d8f3
2452c19:dd:d9:dd:c25:c25:c00a:d8f4/1282c19:dd:d9:dd:c25:c25:c00a:d8f4
2462c19:dd:d9:dd:c25:c25:c00a:d8f5/1282c19:dd:d9:dd:c25:c25:c00a:d8f5
2472c19:dd:d9:dd:c25:c25:c00a:d8f6/1282c19:dd:d9:dd:c25:c25:c00a:d8f6
2482c19:dd:d9:dd:c25:c25:c00a:d8f7/1282c19:dd:d9:dd:c25:c25:c00a:d8f7
2492c19:dd:d9:dd:c25:c25:c00a:d8f8/1282c19:dd:d9:dd:c25:c25:c00a:d8f8
2502c19:dd:d9:dd:c25:c25:c00a:d8f9/1282c19:dd:d9:dd:c25:c25:c00a:d8f9
2512c19:dd:d9:dd:c25:c25:c00a:d8fa/1282c19:dd:d9:dd:c25:c25:c00a:d8fa
2522c19:dd:d9:dd:c25:c25:c00a:d8fb/1282c19:dd:d9:dd:c25:c25:c00a:d8fb
2532c19:dd:d9:dd:c25:c25:c00a:d8fc/1282c19:dd:d9:dd:c25:c25:c00a:d8fc
2542c19:dd:d9:dd:c25:c25:c00a:d8fd/1282c19:dd:d9:dd:c25:c25:c00a:d8fd
2552c19:dd:d9:dd:c25:c25:c00a:d8fe/1282c19:dd:d9:dd:c25:c25:c00a:d8fe
2562c19:dd:d9:dd:c25:c25:c00a:d8ff/1282c19:dd:d9:dd:c25:c25:c00a:d8ff

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.