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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/117
Addresses2,048
/64 networksPart of one
Network
2c19:dd:c25:c25d:dd:dd:dd:d800/117
First address
2c19:dd:c25:c25d:dd:dd:dd:d800
Last address
2c19:dd:c25:c25d:dd:dd:dd:dfff
Addresses
2,048
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:d800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
8.d.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
9.d.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
a.d.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
b.d.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
c.d.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
d.d.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
e.d.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
f.d.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
/117 is not on a 4-bit boundary, so it takes 8 /120 zones.
Split into smaller subnets/127
/118 (2)/119 (4)/120 (8)/121 (16)/124 (128)/127 (1,024)/128 (2,048)

2c19:dd:c25:c25d:dd:dd:dd:d800/117 makes 1,024 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:d800/1272c19:dd:c25:c25d:dd:dd:dd:d801
22c19:dd:c25:c25d:dd:dd:dd:d802/1272c19:dd:c25:c25d:dd:dd:dd:d803
32c19:dd:c25:c25d:dd:dd:dd:d804/1272c19:dd:c25:c25d:dd:dd:dd:d805
42c19:dd:c25:c25d:dd:dd:dd:d806/1272c19:dd:c25:c25d:dd:dd:dd:d807
52c19:dd:c25:c25d:dd:dd:dd:d808/1272c19:dd:c25:c25d:dd:dd:dd:d809
62c19:dd:c25:c25d:dd:dd:dd:d80a/1272c19:dd:c25:c25d:dd:dd:dd:d80b
72c19:dd:c25:c25d:dd:dd:dd:d80c/1272c19:dd:c25:c25d:dd:dd:dd:d80d
82c19:dd:c25:c25d:dd:dd:dd:d80e/1272c19:dd:c25:c25d:dd:dd:dd:d80f
92c19:dd:c25:c25d:dd:dd:dd:d810/1272c19:dd:c25:c25d:dd:dd:dd:d811
102c19:dd:c25:c25d:dd:dd:dd:d812/1272c19:dd:c25:c25d:dd:dd:dd:d813
112c19:dd:c25:c25d:dd:dd:dd:d814/1272c19:dd:c25:c25d:dd:dd:dd:d815
122c19:dd:c25:c25d:dd:dd:dd:d816/1272c19:dd:c25:c25d:dd:dd:dd:d817
132c19:dd:c25:c25d:dd:dd:dd:d818/1272c19:dd:c25:c25d:dd:dd:dd:d819
142c19:dd:c25:c25d:dd:dd:dd:d81a/1272c19:dd:c25:c25d:dd:dd:dd:d81b
152c19:dd:c25:c25d:dd:dd:dd:d81c/1272c19:dd:c25:c25d:dd:dd:dd:d81d
162c19:dd:c25:c25d:dd:dd:dd:d81e/1272c19:dd:c25:c25d:dd:dd:dd:d81f
172c19:dd:c25:c25d:dd:dd:dd:d820/1272c19:dd:c25:c25d:dd:dd:dd:d821
182c19:dd:c25:c25d:dd:dd:dd:d822/1272c19:dd:c25:c25d:dd:dd:dd:d823
192c19:dd:c25:c25d:dd:dd:dd:d824/1272c19:dd:c25:c25d:dd:dd:dd:d825
202c19:dd:c25:c25d:dd:dd:dd:d826/1272c19:dd:c25:c25d:dd:dd:dd:d827
212c19:dd:c25:c25d:dd:dd:dd:d828/1272c19:dd:c25:c25d:dd:dd:dd:d829
222c19:dd:c25:c25d:dd:dd:dd:d82a/1272c19:dd:c25:c25d:dd:dd:dd:d82b
232c19:dd:c25:c25d:dd:dd:dd:d82c/1272c19:dd:c25:c25d:dd:dd:dd:d82d
242c19:dd:c25:c25d:dd:dd:dd:d82e/1272c19:dd:c25:c25d:dd:dd:dd:d82f
252c19:dd:c25:c25d:dd:dd:dd:d830/1272c19:dd:c25:c25d:dd:dd:dd:d831
262c19:dd:c25:c25d:dd:dd:dd:d832/1272c19:dd:c25:c25d:dd:dd:dd:d833
272c19:dd:c25:c25d:dd:dd:dd:d834/1272c19:dd:c25:c25d:dd:dd:dd:d835
282c19:dd:c25:c25d:dd:dd:dd:d836/1272c19:dd:c25:c25d:dd:dd:dd:d837
292c19:dd:c25:c25d:dd:dd:dd:d838/1272c19:dd:c25:c25d:dd:dd:dd:d839
302c19:dd:c25:c25d:dd:dd:dd:d83a/1272c19:dd:c25:c25d:dd:dd:dd:d83b
312c19:dd:c25:c25d:dd:dd:dd:d83c/1272c19:dd:c25:c25d:dd:dd:dd:d83d
322c19:dd:c25:c25d:dd:dd:dd:d83e/1272c19:dd:c25:c25d:dd:dd:dd:d83f
332c19:dd:c25:c25d:dd:dd:dd:d840/1272c19:dd:c25:c25d:dd:dd:dd:d841
342c19:dd:c25:c25d:dd:dd:dd:d842/1272c19:dd:c25:c25d:dd:dd:dd:d843
352c19:dd:c25:c25d:dd:dd:dd:d844/1272c19:dd:c25:c25d:dd:dd:dd:d845
362c19:dd:c25:c25d:dd:dd:dd:d846/1272c19:dd:c25:c25d:dd:dd:dd:d847
372c19:dd:c25:c25d:dd:dd:dd:d848/1272c19:dd:c25:c25d:dd:dd:dd:d849
382c19:dd:c25:c25d:dd:dd:dd:d84a/1272c19:dd:c25:c25d:dd:dd:dd:d84b
392c19:dd:c25:c25d:dd:dd:dd:d84c/1272c19:dd:c25:c25d:dd:dd:dd:d84d
402c19:dd:c25:c25d:dd:dd:dd:d84e/1272c19:dd:c25:c25d:dd:dd:dd:d84f
412c19:dd:c25:c25d:dd:dd:dd:d850/1272c19:dd:c25:c25d:dd:dd:dd:d851
422c19:dd:c25:c25d:dd:dd:dd:d852/1272c19:dd:c25:c25d:dd:dd:dd:d853
432c19:dd:c25:c25d:dd:dd:dd:d854/1272c19:dd:c25:c25d:dd:dd:dd:d855
442c19:dd:c25:c25d:dd:dd:dd:d856/1272c19:dd:c25:c25d:dd:dd:dd:d857
452c19:dd:c25:c25d:dd:dd:dd:d858/1272c19:dd:c25:c25d:dd:dd:dd:d859
462c19:dd:c25:c25d:dd:dd:dd:d85a/1272c19:dd:c25:c25d:dd:dd:dd:d85b
472c19:dd:c25:c25d:dd:dd:dd:d85c/1272c19:dd:c25:c25d:dd:dd:dd:d85d
482c19:dd:c25:c25d:dd:dd:dd:d85e/1272c19:dd:c25:c25d:dd:dd:dd:d85f
492c19:dd:c25:c25d:dd:dd:dd:d860/1272c19:dd:c25:c25d:dd:dd:dd:d861
502c19:dd:c25:c25d:dd:dd:dd:d862/1272c19:dd:c25:c25d:dd:dd:dd:d863
512c19:dd:c25:c25d:dd:dd:dd:d864/1272c19:dd:c25:c25d:dd:dd:dd:d865
522c19:dd:c25:c25d:dd:dd:dd:d866/1272c19:dd:c25:c25d:dd:dd:dd:d867
532c19:dd:c25:c25d:dd:dd:dd:d868/1272c19:dd:c25:c25d:dd:dd:dd:d869
542c19:dd:c25:c25d:dd:dd:dd:d86a/1272c19:dd:c25:c25d:dd:dd:dd:d86b
552c19:dd:c25:c25d:dd:dd:dd:d86c/1272c19:dd:c25:c25d:dd:dd:dd:d86d
562c19:dd:c25:c25d:dd:dd:dd:d86e/1272c19:dd:c25:c25d:dd:dd:dd:d86f
572c19:dd:c25:c25d:dd:dd:dd:d870/1272c19:dd:c25:c25d:dd:dd:dd:d871
582c19:dd:c25:c25d:dd:dd:dd:d872/1272c19:dd:c25:c25d:dd:dd:dd:d873
592c19:dd:c25:c25d:dd:dd:dd:d874/1272c19:dd:c25:c25d:dd:dd:dd:d875
602c19:dd:c25:c25d:dd:dd:dd:d876/1272c19:dd:c25:c25d:dd:dd:dd:d877
612c19:dd:c25:c25d:dd:dd:dd:d878/1272c19:dd:c25:c25d:dd:dd:dd:d879
622c19:dd:c25:c25d:dd:dd:dd:d87a/1272c19:dd:c25:c25d:dd:dd:dd:d87b
632c19:dd:c25:c25d:dd:dd:dd:d87c/1272c19:dd:c25:c25d:dd:dd:dd:d87d
642c19:dd:c25:c25d:dd:dd:dd:d87e/1272c19:dd:c25:c25d:dd:dd:dd:d87f
652c19:dd:c25:c25d:dd:dd:dd:d880/1272c19:dd:c25:c25d:dd:dd:dd:d881
662c19:dd:c25:c25d:dd:dd:dd:d882/1272c19:dd:c25:c25d:dd:dd:dd:d883
672c19:dd:c25:c25d:dd:dd:dd:d884/1272c19:dd:c25:c25d:dd:dd:dd:d885
682c19:dd:c25:c25d:dd:dd:dd:d886/1272c19:dd:c25:c25d:dd:dd:dd:d887
692c19:dd:c25:c25d:dd:dd:dd:d888/1272c19:dd:c25:c25d:dd:dd:dd:d889
702c19:dd:c25:c25d:dd:dd:dd:d88a/1272c19:dd:c25:c25d:dd:dd:dd:d88b
712c19:dd:c25:c25d:dd:dd:dd:d88c/1272c19:dd:c25:c25d:dd:dd:dd:d88d
722c19:dd:c25:c25d:dd:dd:dd:d88e/1272c19:dd:c25:c25d:dd:dd:dd:d88f
732c19:dd:c25:c25d:dd:dd:dd:d890/1272c19:dd:c25:c25d:dd:dd:dd:d891
742c19:dd:c25:c25d:dd:dd:dd:d892/1272c19:dd:c25:c25d:dd:dd:dd:d893
752c19:dd:c25:c25d:dd:dd:dd:d894/1272c19:dd:c25:c25d:dd:dd:dd:d895
762c19:dd:c25:c25d:dd:dd:dd:d896/1272c19:dd:c25:c25d:dd:dd:dd:d897
772c19:dd:c25:c25d:dd:dd:dd:d898/1272c19:dd:c25:c25d:dd:dd:dd:d899
782c19:dd:c25:c25d:dd:dd:dd:d89a/1272c19:dd:c25:c25d:dd:dd:dd:d89b
792c19:dd:c25:c25d:dd:dd:dd:d89c/1272c19:dd:c25:c25d:dd:dd:dd:d89d
802c19:dd:c25:c25d:dd:dd:dd:d89e/1272c19:dd:c25:c25d:dd:dd:dd:d89f
812c19:dd:c25:c25d:dd:dd:dd:d8a0/1272c19:dd:c25:c25d:dd:dd:dd:d8a1
822c19:dd:c25:c25d:dd:dd:dd:d8a2/1272c19:dd:c25:c25d:dd:dd:dd:d8a3
832c19:dd:c25:c25d:dd:dd:dd:d8a4/1272c19:dd:c25:c25d:dd:dd:dd:d8a5
842c19:dd:c25:c25d:dd:dd:dd:d8a6/1272c19:dd:c25:c25d:dd:dd:dd:d8a7
852c19:dd:c25:c25d:dd:dd:dd:d8a8/1272c19:dd:c25:c25d:dd:dd:dd:d8a9
862c19:dd:c25:c25d:dd:dd:dd:d8aa/1272c19:dd:c25:c25d:dd:dd:dd:d8ab
872c19:dd:c25:c25d:dd:dd:dd:d8ac/1272c19:dd:c25:c25d:dd:dd:dd:d8ad
882c19:dd:c25:c25d:dd:dd:dd:d8ae/1272c19:dd:c25:c25d:dd:dd:dd:d8af
892c19:dd:c25:c25d:dd:dd:dd:d8b0/1272c19:dd:c25:c25d:dd:dd:dd:d8b1
902c19:dd:c25:c25d:dd:dd:dd:d8b2/1272c19:dd:c25:c25d:dd:dd:dd:d8b3
912c19:dd:c25:c25d:dd:dd:dd:d8b4/1272c19:dd:c25:c25d:dd:dd:dd:d8b5
922c19:dd:c25:c25d:dd:dd:dd:d8b6/1272c19:dd:c25:c25d:dd:dd:dd:d8b7
932c19:dd:c25:c25d:dd:dd:dd:d8b8/1272c19:dd:c25:c25d:dd:dd:dd:d8b9
942c19:dd:c25:c25d:dd:dd:dd:d8ba/1272c19:dd:c25:c25d:dd:dd:dd:d8bb
952c19:dd:c25:c25d:dd:dd:dd:d8bc/1272c19:dd:c25:c25d:dd:dd:dd:d8bd
962c19:dd:c25:c25d:dd:dd:dd:d8be/1272c19:dd:c25:c25d:dd:dd:dd:d8bf
972c19:dd:c25:c25d:dd:dd:dd:d8c0/1272c19:dd:c25:c25d:dd:dd:dd:d8c1
982c19:dd:c25:c25d:dd:dd:dd:d8c2/1272c19:dd:c25:c25d:dd:dd:dd:d8c3
992c19:dd:c25:c25d:dd:dd:dd:d8c4/1272c19:dd:c25:c25d:dd:dd:dd:d8c5
1002c19:dd:c25:c25d:dd:dd:dd:d8c6/1272c19:dd:c25:c25d:dd:dd:dd:d8c7
1012c19:dd:c25:c25d:dd:dd:dd:d8c8/1272c19:dd:c25:c25d:dd:dd:dd:d8c9
1022c19:dd:c25:c25d:dd:dd:dd:d8ca/1272c19:dd:c25:c25d:dd:dd:dd:d8cb
1032c19:dd:c25:c25d:dd:dd:dd:d8cc/1272c19:dd:c25:c25d:dd:dd:dd:d8cd
1042c19:dd:c25:c25d:dd:dd:dd:d8ce/1272c19:dd:c25:c25d:dd:dd:dd:d8cf
1052c19:dd:c25:c25d:dd:dd:dd:d8d0/1272c19:dd:c25:c25d:dd:dd:dd:d8d1
1062c19:dd:c25:c25d:dd:dd:dd:d8d2/1272c19:dd:c25:c25d:dd:dd:dd:d8d3
1072c19:dd:c25:c25d:dd:dd:dd:d8d4/1272c19:dd:c25:c25d:dd:dd:dd:d8d5
1082c19:dd:c25:c25d:dd:dd:dd:d8d6/1272c19:dd:c25:c25d:dd:dd:dd:d8d7
1092c19:dd:c25:c25d:dd:dd:dd:d8d8/1272c19:dd:c25:c25d:dd:dd:dd:d8d9
1102c19:dd:c25:c25d:dd:dd:dd:d8da/1272c19:dd:c25:c25d:dd:dd:dd:d8db
1112c19:dd:c25:c25d:dd:dd:dd:d8dc/1272c19:dd:c25:c25d:dd:dd:dd:d8dd
1122c19:dd:c25:c25d:dd:dd:dd:d8de/1272c19:dd:c25:c25d:dd:dd:dd:d8df
1132c19:dd:c25:c25d:dd:dd:dd:d8e0/1272c19:dd:c25:c25d:dd:dd:dd:d8e1
1142c19:dd:c25:c25d:dd:dd:dd:d8e2/1272c19:dd:c25:c25d:dd:dd:dd:d8e3
1152c19:dd:c25:c25d:dd:dd:dd:d8e4/1272c19:dd:c25:c25d:dd:dd:dd:d8e5
1162c19:dd:c25:c25d:dd:dd:dd:d8e6/1272c19:dd:c25:c25d:dd:dd:dd:d8e7
1172c19:dd:c25:c25d:dd:dd:dd:d8e8/1272c19:dd:c25:c25d:dd:dd:dd:d8e9
1182c19:dd:c25:c25d:dd:dd:dd:d8ea/1272c19:dd:c25:c25d:dd:dd:dd:d8eb
1192c19:dd:c25:c25d:dd:dd:dd:d8ec/1272c19:dd:c25:c25d:dd:dd:dd:d8ed
1202c19:dd:c25:c25d:dd:dd:dd:d8ee/1272c19:dd:c25:c25d:dd:dd:dd:d8ef
1212c19:dd:c25:c25d:dd:dd:dd:d8f0/1272c19:dd:c25:c25d:dd:dd:dd:d8f1
1222c19:dd:c25:c25d:dd:dd:dd:d8f2/1272c19:dd:c25:c25d:dd:dd:dd:d8f3
1232c19:dd:c25:c25d:dd:dd:dd:d8f4/1272c19:dd:c25:c25d:dd:dd:dd:d8f5
1242c19:dd:c25:c25d:dd:dd:dd:d8f6/1272c19:dd:c25:c25d:dd:dd:dd:d8f7
1252c19:dd:c25:c25d:dd:dd:dd:d8f8/1272c19:dd:c25:c25d:dd:dd:dd:d8f9
1262c19:dd:c25:c25d:dd:dd:dd:d8fa/1272c19:dd:c25:c25d:dd:dd:dd:d8fb
1272c19:dd:c25:c25d:dd:dd:dd:d8fc/1272c19:dd:c25:c25d:dd:dd:dd:d8fd
1282c19:dd:c25:c25d:dd:dd:dd:d8fe/1272c19:dd:c25:c25d:dd:dd:dd:d8ff
1292c19:dd:c25:c25d:dd:dd:dd:d900/1272c19:dd:c25:c25d:dd:dd:dd:d901
1302c19:dd:c25:c25d:dd:dd:dd:d902/1272c19:dd:c25:c25d:dd:dd:dd:d903
1312c19:dd:c25:c25d:dd:dd:dd:d904/1272c19:dd:c25:c25d:dd:dd:dd:d905
1322c19:dd:c25:c25d:dd:dd:dd:d906/1272c19:dd:c25:c25d:dd:dd:dd:d907
1332c19:dd:c25:c25d:dd:dd:dd:d908/1272c19:dd:c25:c25d:dd:dd:dd:d909
1342c19:dd:c25:c25d:dd:dd:dd:d90a/1272c19:dd:c25:c25d:dd:dd:dd:d90b
1352c19:dd:c25:c25d:dd:dd:dd:d90c/1272c19:dd:c25:c25d:dd:dd:dd:d90d
1362c19:dd:c25:c25d:dd:dd:dd:d90e/1272c19:dd:c25:c25d:dd:dd:dd:d90f
1372c19:dd:c25:c25d:dd:dd:dd:d910/1272c19:dd:c25:c25d:dd:dd:dd:d911
1382c19:dd:c25:c25d:dd:dd:dd:d912/1272c19:dd:c25:c25d:dd:dd:dd:d913
1392c19:dd:c25:c25d:dd:dd:dd:d914/1272c19:dd:c25:c25d:dd:dd:dd:d915
1402c19:dd:c25:c25d:dd:dd:dd:d916/1272c19:dd:c25:c25d:dd:dd:dd:d917
1412c19:dd:c25:c25d:dd:dd:dd:d918/1272c19:dd:c25:c25d:dd:dd:dd:d919
1422c19:dd:c25:c25d:dd:dd:dd:d91a/1272c19:dd:c25:c25d:dd:dd:dd:d91b
1432c19:dd:c25:c25d:dd:dd:dd:d91c/1272c19:dd:c25:c25d:dd:dd:dd:d91d
1442c19:dd:c25:c25d:dd:dd:dd:d91e/1272c19:dd:c25:c25d:dd:dd:dd:d91f
1452c19:dd:c25:c25d:dd:dd:dd:d920/1272c19:dd:c25:c25d:dd:dd:dd:d921
1462c19:dd:c25:c25d:dd:dd:dd:d922/1272c19:dd:c25:c25d:dd:dd:dd:d923
1472c19:dd:c25:c25d:dd:dd:dd:d924/1272c19:dd:c25:c25d:dd:dd:dd:d925
1482c19:dd:c25:c25d:dd:dd:dd:d926/1272c19:dd:c25:c25d:dd:dd:dd:d927
1492c19:dd:c25:c25d:dd:dd:dd:d928/1272c19:dd:c25:c25d:dd:dd:dd:d929
1502c19:dd:c25:c25d:dd:dd:dd:d92a/1272c19:dd:c25:c25d:dd:dd:dd:d92b
1512c19:dd:c25:c25d:dd:dd:dd:d92c/1272c19:dd:c25:c25d:dd:dd:dd:d92d
1522c19:dd:c25:c25d:dd:dd:dd:d92e/1272c19:dd:c25:c25d:dd:dd:dd:d92f
1532c19:dd:c25:c25d:dd:dd:dd:d930/1272c19:dd:c25:c25d:dd:dd:dd:d931
1542c19:dd:c25:c25d:dd:dd:dd:d932/1272c19:dd:c25:c25d:dd:dd:dd:d933
1552c19:dd:c25:c25d:dd:dd:dd:d934/1272c19:dd:c25:c25d:dd:dd:dd:d935
1562c19:dd:c25:c25d:dd:dd:dd:d936/1272c19:dd:c25:c25d:dd:dd:dd:d937
1572c19:dd:c25:c25d:dd:dd:dd:d938/1272c19:dd:c25:c25d:dd:dd:dd:d939
1582c19:dd:c25:c25d:dd:dd:dd:d93a/1272c19:dd:c25:c25d:dd:dd:dd:d93b
1592c19:dd:c25:c25d:dd:dd:dd:d93c/1272c19:dd:c25:c25d:dd:dd:dd:d93d
1602c19:dd:c25:c25d:dd:dd:dd:d93e/1272c19:dd:c25:c25d:dd:dd:dd:d93f
1612c19:dd:c25:c25d:dd:dd:dd:d940/1272c19:dd:c25:c25d:dd:dd:dd:d941
1622c19:dd:c25:c25d:dd:dd:dd:d942/1272c19:dd:c25:c25d:dd:dd:dd:d943
1632c19:dd:c25:c25d:dd:dd:dd:d944/1272c19:dd:c25:c25d:dd:dd:dd:d945
1642c19:dd:c25:c25d:dd:dd:dd:d946/1272c19:dd:c25:c25d:dd:dd:dd:d947
1652c19:dd:c25:c25d:dd:dd:dd:d948/1272c19:dd:c25:c25d:dd:dd:dd:d949
1662c19:dd:c25:c25d:dd:dd:dd:d94a/1272c19:dd:c25:c25d:dd:dd:dd:d94b
1672c19:dd:c25:c25d:dd:dd:dd:d94c/1272c19:dd:c25:c25d:dd:dd:dd:d94d
1682c19:dd:c25:c25d:dd:dd:dd:d94e/1272c19:dd:c25:c25d:dd:dd:dd:d94f
1692c19:dd:c25:c25d:dd:dd:dd:d950/1272c19:dd:c25:c25d:dd:dd:dd:d951
1702c19:dd:c25:c25d:dd:dd:dd:d952/1272c19:dd:c25:c25d:dd:dd:dd:d953
1712c19:dd:c25:c25d:dd:dd:dd:d954/1272c19:dd:c25:c25d:dd:dd:dd:d955
1722c19:dd:c25:c25d:dd:dd:dd:d956/1272c19:dd:c25:c25d:dd:dd:dd:d957
1732c19:dd:c25:c25d:dd:dd:dd:d958/1272c19:dd:c25:c25d:dd:dd:dd:d959
1742c19:dd:c25:c25d:dd:dd:dd:d95a/1272c19:dd:c25:c25d:dd:dd:dd:d95b
1752c19:dd:c25:c25d:dd:dd:dd:d95c/1272c19:dd:c25:c25d:dd:dd:dd:d95d
1762c19:dd:c25:c25d:dd:dd:dd:d95e/1272c19:dd:c25:c25d:dd:dd:dd:d95f
1772c19:dd:c25:c25d:dd:dd:dd:d960/1272c19:dd:c25:c25d:dd:dd:dd:d961
1782c19:dd:c25:c25d:dd:dd:dd:d962/1272c19:dd:c25:c25d:dd:dd:dd:d963
1792c19:dd:c25:c25d:dd:dd:dd:d964/1272c19:dd:c25:c25d:dd:dd:dd:d965
1802c19:dd:c25:c25d:dd:dd:dd:d966/1272c19:dd:c25:c25d:dd:dd:dd:d967
1812c19:dd:c25:c25d:dd:dd:dd:d968/1272c19:dd:c25:c25d:dd:dd:dd:d969
1822c19:dd:c25:c25d:dd:dd:dd:d96a/1272c19:dd:c25:c25d:dd:dd:dd:d96b
1832c19:dd:c25:c25d:dd:dd:dd:d96c/1272c19:dd:c25:c25d:dd:dd:dd:d96d
1842c19:dd:c25:c25d:dd:dd:dd:d96e/1272c19:dd:c25:c25d:dd:dd:dd:d96f
1852c19:dd:c25:c25d:dd:dd:dd:d970/1272c19:dd:c25:c25d:dd:dd:dd:d971
1862c19:dd:c25:c25d:dd:dd:dd:d972/1272c19:dd:c25:c25d:dd:dd:dd:d973
1872c19:dd:c25:c25d:dd:dd:dd:d974/1272c19:dd:c25:c25d:dd:dd:dd:d975
1882c19:dd:c25:c25d:dd:dd:dd:d976/1272c19:dd:c25:c25d:dd:dd:dd:d977
1892c19:dd:c25:c25d:dd:dd:dd:d978/1272c19:dd:c25:c25d:dd:dd:dd:d979
1902c19:dd:c25:c25d:dd:dd:dd:d97a/1272c19:dd:c25:c25d:dd:dd:dd:d97b
1912c19:dd:c25:c25d:dd:dd:dd:d97c/1272c19:dd:c25:c25d:dd:dd:dd:d97d
1922c19:dd:c25:c25d:dd:dd:dd:d97e/1272c19:dd:c25:c25d:dd:dd:dd:d97f
1932c19:dd:c25:c25d:dd:dd:dd:d980/1272c19:dd:c25:c25d:dd:dd:dd:d981
1942c19:dd:c25:c25d:dd:dd:dd:d982/1272c19:dd:c25:c25d:dd:dd:dd:d983
1952c19:dd:c25:c25d:dd:dd:dd:d984/1272c19:dd:c25:c25d:dd:dd:dd:d985
1962c19:dd:c25:c25d:dd:dd:dd:d986/1272c19:dd:c25:c25d:dd:dd:dd:d987
1972c19:dd:c25:c25d:dd:dd:dd:d988/1272c19:dd:c25:c25d:dd:dd:dd:d989
1982c19:dd:c25:c25d:dd:dd:dd:d98a/1272c19:dd:c25:c25d:dd:dd:dd:d98b
1992c19:dd:c25:c25d:dd:dd:dd:d98c/1272c19:dd:c25:c25d:dd:dd:dd:d98d
2002c19:dd:c25:c25d:dd:dd:dd:d98e/1272c19:dd:c25:c25d:dd:dd:dd:d98f
2012c19:dd:c25:c25d:dd:dd:dd:d990/1272c19:dd:c25:c25d:dd:dd:dd:d991
2022c19:dd:c25:c25d:dd:dd:dd:d992/1272c19:dd:c25:c25d:dd:dd:dd:d993
2032c19:dd:c25:c25d:dd:dd:dd:d994/1272c19:dd:c25:c25d:dd:dd:dd:d995
2042c19:dd:c25:c25d:dd:dd:dd:d996/1272c19:dd:c25:c25d:dd:dd:dd:d997
2052c19:dd:c25:c25d:dd:dd:dd:d998/1272c19:dd:c25:c25d:dd:dd:dd:d999
2062c19:dd:c25:c25d:dd:dd:dd:d99a/1272c19:dd:c25:c25d:dd:dd:dd:d99b
2072c19:dd:c25:c25d:dd:dd:dd:d99c/1272c19:dd:c25:c25d:dd:dd:dd:d99d
2082c19:dd:c25:c25d:dd:dd:dd:d99e/1272c19:dd:c25:c25d:dd:dd:dd:d99f
2092c19:dd:c25:c25d:dd:dd:dd:d9a0/1272c19:dd:c25:c25d:dd:dd:dd:d9a1
2102c19:dd:c25:c25d:dd:dd:dd:d9a2/1272c19:dd:c25:c25d:dd:dd:dd:d9a3
2112c19:dd:c25:c25d:dd:dd:dd:d9a4/1272c19:dd:c25:c25d:dd:dd:dd:d9a5
2122c19:dd:c25:c25d:dd:dd:dd:d9a6/1272c19:dd:c25:c25d:dd:dd:dd:d9a7
2132c19:dd:c25:c25d:dd:dd:dd:d9a8/1272c19:dd:c25:c25d:dd:dd:dd:d9a9
2142c19:dd:c25:c25d:dd:dd:dd:d9aa/1272c19:dd:c25:c25d:dd:dd:dd:d9ab
2152c19:dd:c25:c25d:dd:dd:dd:d9ac/1272c19:dd:c25:c25d:dd:dd:dd:d9ad
2162c19:dd:c25:c25d:dd:dd:dd:d9ae/1272c19:dd:c25:c25d:dd:dd:dd:d9af
2172c19:dd:c25:c25d:dd:dd:dd:d9b0/1272c19:dd:c25:c25d:dd:dd:dd:d9b1
2182c19:dd:c25:c25d:dd:dd:dd:d9b2/1272c19:dd:c25:c25d:dd:dd:dd:d9b3
2192c19:dd:c25:c25d:dd:dd:dd:d9b4/1272c19:dd:c25:c25d:dd:dd:dd:d9b5
2202c19:dd:c25:c25d:dd:dd:dd:d9b6/1272c19:dd:c25:c25d:dd:dd:dd:d9b7
2212c19:dd:c25:c25d:dd:dd:dd:d9b8/1272c19:dd:c25:c25d:dd:dd:dd:d9b9
2222c19:dd:c25:c25d:dd:dd:dd:d9ba/1272c19:dd:c25:c25d:dd:dd:dd:d9bb
2232c19:dd:c25:c25d:dd:dd:dd:d9bc/1272c19:dd:c25:c25d:dd:dd:dd:d9bd
2242c19:dd:c25:c25d:dd:dd:dd:d9be/1272c19:dd:c25:c25d:dd:dd:dd:d9bf
2252c19:dd:c25:c25d:dd:dd:dd:d9c0/1272c19:dd:c25:c25d:dd:dd:dd:d9c1
2262c19:dd:c25:c25d:dd:dd:dd:d9c2/1272c19:dd:c25:c25d:dd:dd:dd:d9c3
2272c19:dd:c25:c25d:dd:dd:dd:d9c4/1272c19:dd:c25:c25d:dd:dd:dd:d9c5
2282c19:dd:c25:c25d:dd:dd:dd:d9c6/1272c19:dd:c25:c25d:dd:dd:dd:d9c7
2292c19:dd:c25:c25d:dd:dd:dd:d9c8/1272c19:dd:c25:c25d:dd:dd:dd:d9c9
2302c19:dd:c25:c25d:dd:dd:dd:d9ca/1272c19:dd:c25:c25d:dd:dd:dd:d9cb
2312c19:dd:c25:c25d:dd:dd:dd:d9cc/1272c19:dd:c25:c25d:dd:dd:dd:d9cd
2322c19:dd:c25:c25d:dd:dd:dd:d9ce/1272c19:dd:c25:c25d:dd:dd:dd:d9cf
2332c19:dd:c25:c25d:dd:dd:dd:d9d0/1272c19:dd:c25:c25d:dd:dd:dd:d9d1
2342c19:dd:c25:c25d:dd:dd:dd:d9d2/1272c19:dd:c25:c25d:dd:dd:dd:d9d3
2352c19:dd:c25:c25d:dd:dd:dd:d9d4/1272c19:dd:c25:c25d:dd:dd:dd:d9d5
2362c19:dd:c25:c25d:dd:dd:dd:d9d6/1272c19:dd:c25:c25d:dd:dd:dd:d9d7
2372c19:dd:c25:c25d:dd:dd:dd:d9d8/1272c19:dd:c25:c25d:dd:dd:dd:d9d9
2382c19:dd:c25:c25d:dd:dd:dd:d9da/1272c19:dd:c25:c25d:dd:dd:dd:d9db
2392c19:dd:c25:c25d:dd:dd:dd:d9dc/1272c19:dd:c25:c25d:dd:dd:dd:d9dd
2402c19:dd:c25:c25d:dd:dd:dd:d9de/1272c19:dd:c25:c25d:dd:dd:dd:d9df
2412c19:dd:c25:c25d:dd:dd:dd:d9e0/1272c19:dd:c25:c25d:dd:dd:dd:d9e1
2422c19:dd:c25:c25d:dd:dd:dd:d9e2/1272c19:dd:c25:c25d:dd:dd:dd:d9e3
2432c19:dd:c25:c25d:dd:dd:dd:d9e4/1272c19:dd:c25:c25d:dd:dd:dd:d9e5
2442c19:dd:c25:c25d:dd:dd:dd:d9e6/1272c19:dd:c25:c25d:dd:dd:dd:d9e7
2452c19:dd:c25:c25d:dd:dd:dd:d9e8/1272c19:dd:c25:c25d:dd:dd:dd:d9e9
2462c19:dd:c25:c25d:dd:dd:dd:d9ea/1272c19:dd:c25:c25d:dd:dd:dd:d9eb
2472c19:dd:c25:c25d:dd:dd:dd:d9ec/1272c19:dd:c25:c25d:dd:dd:dd:d9ed
2482c19:dd:c25:c25d:dd:dd:dd:d9ee/1272c19:dd:c25:c25d:dd:dd:dd:d9ef
2492c19:dd:c25:c25d:dd:dd:dd:d9f0/1272c19:dd:c25:c25d:dd:dd:dd:d9f1
2502c19:dd:c25:c25d:dd:dd:dd:d9f2/1272c19:dd:c25:c25d:dd:dd:dd:d9f3
2512c19:dd:c25:c25d:dd:dd:dd:d9f4/1272c19:dd:c25:c25d:dd:dd:dd:d9f5
2522c19:dd:c25:c25d:dd:dd:dd:d9f6/1272c19:dd:c25:c25d:dd:dd:dd:d9f7
2532c19:dd:c25:c25d:dd:dd:dd:d9f8/1272c19:dd:c25:c25d:dd:dd:dd:d9f9
2542c19:dd:c25:c25d:dd:dd:dd:d9fa/1272c19:dd:c25:c25d:dd:dd:dd:d9fb
2552c19:dd:c25:c25d:dd:dd:dd:d9fc/1272c19:dd:c25:c25d:dd:dd:dd:d9fd
2562c19:dd:c25:c25d:dd:dd:dd:d9fe/1272c19:dd:c25:c25d:dd:dd:dd:d9ff

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.