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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:d9:dd:c25:c25:94de:f800/117
First address
2c19:dd:d9:dd:c25:c25:94de:f800
Last address
2c19:dd:d9:dd:c25:c25:94de:ffff
Addresses
2,048
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:f800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
8.f.e.d.4.9.5.2.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.f.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
a.f.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
b.f.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
c.f.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
d.f.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
e.f.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
f.f.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
/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:d9:dd:c25:c25:94de:f800/117 makes 1,024 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:f800/1272c19:dd:d9:dd:c25:c25:94de:f801
22c19:dd:d9:dd:c25:c25:94de:f802/1272c19:dd:d9:dd:c25:c25:94de:f803
32c19:dd:d9:dd:c25:c25:94de:f804/1272c19:dd:d9:dd:c25:c25:94de:f805
42c19:dd:d9:dd:c25:c25:94de:f806/1272c19:dd:d9:dd:c25:c25:94de:f807
52c19:dd:d9:dd:c25:c25:94de:f808/1272c19:dd:d9:dd:c25:c25:94de:f809
62c19:dd:d9:dd:c25:c25:94de:f80a/1272c19:dd:d9:dd:c25:c25:94de:f80b
72c19:dd:d9:dd:c25:c25:94de:f80c/1272c19:dd:d9:dd:c25:c25:94de:f80d
82c19:dd:d9:dd:c25:c25:94de:f80e/1272c19:dd:d9:dd:c25:c25:94de:f80f
92c19:dd:d9:dd:c25:c25:94de:f810/1272c19:dd:d9:dd:c25:c25:94de:f811
102c19:dd:d9:dd:c25:c25:94de:f812/1272c19:dd:d9:dd:c25:c25:94de:f813
112c19:dd:d9:dd:c25:c25:94de:f814/1272c19:dd:d9:dd:c25:c25:94de:f815
122c19:dd:d9:dd:c25:c25:94de:f816/1272c19:dd:d9:dd:c25:c25:94de:f817
132c19:dd:d9:dd:c25:c25:94de:f818/1272c19:dd:d9:dd:c25:c25:94de:f819
142c19:dd:d9:dd:c25:c25:94de:f81a/1272c19:dd:d9:dd:c25:c25:94de:f81b
152c19:dd:d9:dd:c25:c25:94de:f81c/1272c19:dd:d9:dd:c25:c25:94de:f81d
162c19:dd:d9:dd:c25:c25:94de:f81e/1272c19:dd:d9:dd:c25:c25:94de:f81f
172c19:dd:d9:dd:c25:c25:94de:f820/1272c19:dd:d9:dd:c25:c25:94de:f821
182c19:dd:d9:dd:c25:c25:94de:f822/1272c19:dd:d9:dd:c25:c25:94de:f823
192c19:dd:d9:dd:c25:c25:94de:f824/1272c19:dd:d9:dd:c25:c25:94de:f825
202c19:dd:d9:dd:c25:c25:94de:f826/1272c19:dd:d9:dd:c25:c25:94de:f827
212c19:dd:d9:dd:c25:c25:94de:f828/1272c19:dd:d9:dd:c25:c25:94de:f829
222c19:dd:d9:dd:c25:c25:94de:f82a/1272c19:dd:d9:dd:c25:c25:94de:f82b
232c19:dd:d9:dd:c25:c25:94de:f82c/1272c19:dd:d9:dd:c25:c25:94de:f82d
242c19:dd:d9:dd:c25:c25:94de:f82e/1272c19:dd:d9:dd:c25:c25:94de:f82f
252c19:dd:d9:dd:c25:c25:94de:f830/1272c19:dd:d9:dd:c25:c25:94de:f831
262c19:dd:d9:dd:c25:c25:94de:f832/1272c19:dd:d9:dd:c25:c25:94de:f833
272c19:dd:d9:dd:c25:c25:94de:f834/1272c19:dd:d9:dd:c25:c25:94de:f835
282c19:dd:d9:dd:c25:c25:94de:f836/1272c19:dd:d9:dd:c25:c25:94de:f837
292c19:dd:d9:dd:c25:c25:94de:f838/1272c19:dd:d9:dd:c25:c25:94de:f839
302c19:dd:d9:dd:c25:c25:94de:f83a/1272c19:dd:d9:dd:c25:c25:94de:f83b
312c19:dd:d9:dd:c25:c25:94de:f83c/1272c19:dd:d9:dd:c25:c25:94de:f83d
322c19:dd:d9:dd:c25:c25:94de:f83e/1272c19:dd:d9:dd:c25:c25:94de:f83f
332c19:dd:d9:dd:c25:c25:94de:f840/1272c19:dd:d9:dd:c25:c25:94de:f841
342c19:dd:d9:dd:c25:c25:94de:f842/1272c19:dd:d9:dd:c25:c25:94de:f843
352c19:dd:d9:dd:c25:c25:94de:f844/1272c19:dd:d9:dd:c25:c25:94de:f845
362c19:dd:d9:dd:c25:c25:94de:f846/1272c19:dd:d9:dd:c25:c25:94de:f847
372c19:dd:d9:dd:c25:c25:94de:f848/1272c19:dd:d9:dd:c25:c25:94de:f849
382c19:dd:d9:dd:c25:c25:94de:f84a/1272c19:dd:d9:dd:c25:c25:94de:f84b
392c19:dd:d9:dd:c25:c25:94de:f84c/1272c19:dd:d9:dd:c25:c25:94de:f84d
402c19:dd:d9:dd:c25:c25:94de:f84e/1272c19:dd:d9:dd:c25:c25:94de:f84f
412c19:dd:d9:dd:c25:c25:94de:f850/1272c19:dd:d9:dd:c25:c25:94de:f851
422c19:dd:d9:dd:c25:c25:94de:f852/1272c19:dd:d9:dd:c25:c25:94de:f853
432c19:dd:d9:dd:c25:c25:94de:f854/1272c19:dd:d9:dd:c25:c25:94de:f855
442c19:dd:d9:dd:c25:c25:94de:f856/1272c19:dd:d9:dd:c25:c25:94de:f857
452c19:dd:d9:dd:c25:c25:94de:f858/1272c19:dd:d9:dd:c25:c25:94de:f859
462c19:dd:d9:dd:c25:c25:94de:f85a/1272c19:dd:d9:dd:c25:c25:94de:f85b
472c19:dd:d9:dd:c25:c25:94de:f85c/1272c19:dd:d9:dd:c25:c25:94de:f85d
482c19:dd:d9:dd:c25:c25:94de:f85e/1272c19:dd:d9:dd:c25:c25:94de:f85f
492c19:dd:d9:dd:c25:c25:94de:f860/1272c19:dd:d9:dd:c25:c25:94de:f861
502c19:dd:d9:dd:c25:c25:94de:f862/1272c19:dd:d9:dd:c25:c25:94de:f863
512c19:dd:d9:dd:c25:c25:94de:f864/1272c19:dd:d9:dd:c25:c25:94de:f865
522c19:dd:d9:dd:c25:c25:94de:f866/1272c19:dd:d9:dd:c25:c25:94de:f867
532c19:dd:d9:dd:c25:c25:94de:f868/1272c19:dd:d9:dd:c25:c25:94de:f869
542c19:dd:d9:dd:c25:c25:94de:f86a/1272c19:dd:d9:dd:c25:c25:94de:f86b
552c19:dd:d9:dd:c25:c25:94de:f86c/1272c19:dd:d9:dd:c25:c25:94de:f86d
562c19:dd:d9:dd:c25:c25:94de:f86e/1272c19:dd:d9:dd:c25:c25:94de:f86f
572c19:dd:d9:dd:c25:c25:94de:f870/1272c19:dd:d9:dd:c25:c25:94de:f871
582c19:dd:d9:dd:c25:c25:94de:f872/1272c19:dd:d9:dd:c25:c25:94de:f873
592c19:dd:d9:dd:c25:c25:94de:f874/1272c19:dd:d9:dd:c25:c25:94de:f875
602c19:dd:d9:dd:c25:c25:94de:f876/1272c19:dd:d9:dd:c25:c25:94de:f877
612c19:dd:d9:dd:c25:c25:94de:f878/1272c19:dd:d9:dd:c25:c25:94de:f879
622c19:dd:d9:dd:c25:c25:94de:f87a/1272c19:dd:d9:dd:c25:c25:94de:f87b
632c19:dd:d9:dd:c25:c25:94de:f87c/1272c19:dd:d9:dd:c25:c25:94de:f87d
642c19:dd:d9:dd:c25:c25:94de:f87e/1272c19:dd:d9:dd:c25:c25:94de:f87f
652c19:dd:d9:dd:c25:c25:94de:f880/1272c19:dd:d9:dd:c25:c25:94de:f881
662c19:dd:d9:dd:c25:c25:94de:f882/1272c19:dd:d9:dd:c25:c25:94de:f883
672c19:dd:d9:dd:c25:c25:94de:f884/1272c19:dd:d9:dd:c25:c25:94de:f885
682c19:dd:d9:dd:c25:c25:94de:f886/1272c19:dd:d9:dd:c25:c25:94de:f887
692c19:dd:d9:dd:c25:c25:94de:f888/1272c19:dd:d9:dd:c25:c25:94de:f889
702c19:dd:d9:dd:c25:c25:94de:f88a/1272c19:dd:d9:dd:c25:c25:94de:f88b
712c19:dd:d9:dd:c25:c25:94de:f88c/1272c19:dd:d9:dd:c25:c25:94de:f88d
722c19:dd:d9:dd:c25:c25:94de:f88e/1272c19:dd:d9:dd:c25:c25:94de:f88f
732c19:dd:d9:dd:c25:c25:94de:f890/1272c19:dd:d9:dd:c25:c25:94de:f891
742c19:dd:d9:dd:c25:c25:94de:f892/1272c19:dd:d9:dd:c25:c25:94de:f893
752c19:dd:d9:dd:c25:c25:94de:f894/1272c19:dd:d9:dd:c25:c25:94de:f895
762c19:dd:d9:dd:c25:c25:94de:f896/1272c19:dd:d9:dd:c25:c25:94de:f897
772c19:dd:d9:dd:c25:c25:94de:f898/1272c19:dd:d9:dd:c25:c25:94de:f899
782c19:dd:d9:dd:c25:c25:94de:f89a/1272c19:dd:d9:dd:c25:c25:94de:f89b
792c19:dd:d9:dd:c25:c25:94de:f89c/1272c19:dd:d9:dd:c25:c25:94de:f89d
802c19:dd:d9:dd:c25:c25:94de:f89e/1272c19:dd:d9:dd:c25:c25:94de:f89f
812c19:dd:d9:dd:c25:c25:94de:f8a0/1272c19:dd:d9:dd:c25:c25:94de:f8a1
822c19:dd:d9:dd:c25:c25:94de:f8a2/1272c19:dd:d9:dd:c25:c25:94de:f8a3
832c19:dd:d9:dd:c25:c25:94de:f8a4/1272c19:dd:d9:dd:c25:c25:94de:f8a5
842c19:dd:d9:dd:c25:c25:94de:f8a6/1272c19:dd:d9:dd:c25:c25:94de:f8a7
852c19:dd:d9:dd:c25:c25:94de:f8a8/1272c19:dd:d9:dd:c25:c25:94de:f8a9
862c19:dd:d9:dd:c25:c25:94de:f8aa/1272c19:dd:d9:dd:c25:c25:94de:f8ab
872c19:dd:d9:dd:c25:c25:94de:f8ac/1272c19:dd:d9:dd:c25:c25:94de:f8ad
882c19:dd:d9:dd:c25:c25:94de:f8ae/1272c19:dd:d9:dd:c25:c25:94de:f8af
892c19:dd:d9:dd:c25:c25:94de:f8b0/1272c19:dd:d9:dd:c25:c25:94de:f8b1
902c19:dd:d9:dd:c25:c25:94de:f8b2/1272c19:dd:d9:dd:c25:c25:94de:f8b3
912c19:dd:d9:dd:c25:c25:94de:f8b4/1272c19:dd:d9:dd:c25:c25:94de:f8b5
922c19:dd:d9:dd:c25:c25:94de:f8b6/1272c19:dd:d9:dd:c25:c25:94de:f8b7
932c19:dd:d9:dd:c25:c25:94de:f8b8/1272c19:dd:d9:dd:c25:c25:94de:f8b9
942c19:dd:d9:dd:c25:c25:94de:f8ba/1272c19:dd:d9:dd:c25:c25:94de:f8bb
952c19:dd:d9:dd:c25:c25:94de:f8bc/1272c19:dd:d9:dd:c25:c25:94de:f8bd
962c19:dd:d9:dd:c25:c25:94de:f8be/1272c19:dd:d9:dd:c25:c25:94de:f8bf
972c19:dd:d9:dd:c25:c25:94de:f8c0/1272c19:dd:d9:dd:c25:c25:94de:f8c1
982c19:dd:d9:dd:c25:c25:94de:f8c2/1272c19:dd:d9:dd:c25:c25:94de:f8c3
992c19:dd:d9:dd:c25:c25:94de:f8c4/1272c19:dd:d9:dd:c25:c25:94de:f8c5
1002c19:dd:d9:dd:c25:c25:94de:f8c6/1272c19:dd:d9:dd:c25:c25:94de:f8c7
1012c19:dd:d9:dd:c25:c25:94de:f8c8/1272c19:dd:d9:dd:c25:c25:94de:f8c9
1022c19:dd:d9:dd:c25:c25:94de:f8ca/1272c19:dd:d9:dd:c25:c25:94de:f8cb
1032c19:dd:d9:dd:c25:c25:94de:f8cc/1272c19:dd:d9:dd:c25:c25:94de:f8cd
1042c19:dd:d9:dd:c25:c25:94de:f8ce/1272c19:dd:d9:dd:c25:c25:94de:f8cf
1052c19:dd:d9:dd:c25:c25:94de:f8d0/1272c19:dd:d9:dd:c25:c25:94de:f8d1
1062c19:dd:d9:dd:c25:c25:94de:f8d2/1272c19:dd:d9:dd:c25:c25:94de:f8d3
1072c19:dd:d9:dd:c25:c25:94de:f8d4/1272c19:dd:d9:dd:c25:c25:94de:f8d5
1082c19:dd:d9:dd:c25:c25:94de:f8d6/1272c19:dd:d9:dd:c25:c25:94de:f8d7
1092c19:dd:d9:dd:c25:c25:94de:f8d8/1272c19:dd:d9:dd:c25:c25:94de:f8d9
1102c19:dd:d9:dd:c25:c25:94de:f8da/1272c19:dd:d9:dd:c25:c25:94de:f8db
1112c19:dd:d9:dd:c25:c25:94de:f8dc/1272c19:dd:d9:dd:c25:c25:94de:f8dd
1122c19:dd:d9:dd:c25:c25:94de:f8de/1272c19:dd:d9:dd:c25:c25:94de:f8df
1132c19:dd:d9:dd:c25:c25:94de:f8e0/1272c19:dd:d9:dd:c25:c25:94de:f8e1
1142c19:dd:d9:dd:c25:c25:94de:f8e2/1272c19:dd:d9:dd:c25:c25:94de:f8e3
1152c19:dd:d9:dd:c25:c25:94de:f8e4/1272c19:dd:d9:dd:c25:c25:94de:f8e5
1162c19:dd:d9:dd:c25:c25:94de:f8e6/1272c19:dd:d9:dd:c25:c25:94de:f8e7
1172c19:dd:d9:dd:c25:c25:94de:f8e8/1272c19:dd:d9:dd:c25:c25:94de:f8e9
1182c19:dd:d9:dd:c25:c25:94de:f8ea/1272c19:dd:d9:dd:c25:c25:94de:f8eb
1192c19:dd:d9:dd:c25:c25:94de:f8ec/1272c19:dd:d9:dd:c25:c25:94de:f8ed
1202c19:dd:d9:dd:c25:c25:94de:f8ee/1272c19:dd:d9:dd:c25:c25:94de:f8ef
1212c19:dd:d9:dd:c25:c25:94de:f8f0/1272c19:dd:d9:dd:c25:c25:94de:f8f1
1222c19:dd:d9:dd:c25:c25:94de:f8f2/1272c19:dd:d9:dd:c25:c25:94de:f8f3
1232c19:dd:d9:dd:c25:c25:94de:f8f4/1272c19:dd:d9:dd:c25:c25:94de:f8f5
1242c19:dd:d9:dd:c25:c25:94de:f8f6/1272c19:dd:d9:dd:c25:c25:94de:f8f7
1252c19:dd:d9:dd:c25:c25:94de:f8f8/1272c19:dd:d9:dd:c25:c25:94de:f8f9
1262c19:dd:d9:dd:c25:c25:94de:f8fa/1272c19:dd:d9:dd:c25:c25:94de:f8fb
1272c19:dd:d9:dd:c25:c25:94de:f8fc/1272c19:dd:d9:dd:c25:c25:94de:f8fd
1282c19:dd:d9:dd:c25:c25:94de:f8fe/1272c19:dd:d9:dd:c25:c25:94de:f8ff
1292c19:dd:d9:dd:c25:c25:94de:f900/1272c19:dd:d9:dd:c25:c25:94de:f901
1302c19:dd:d9:dd:c25:c25:94de:f902/1272c19:dd:d9:dd:c25:c25:94de:f903
1312c19:dd:d9:dd:c25:c25:94de:f904/1272c19:dd:d9:dd:c25:c25:94de:f905
1322c19:dd:d9:dd:c25:c25:94de:f906/1272c19:dd:d9:dd:c25:c25:94de:f907
1332c19:dd:d9:dd:c25:c25:94de:f908/1272c19:dd:d9:dd:c25:c25:94de:f909
1342c19:dd:d9:dd:c25:c25:94de:f90a/1272c19:dd:d9:dd:c25:c25:94de:f90b
1352c19:dd:d9:dd:c25:c25:94de:f90c/1272c19:dd:d9:dd:c25:c25:94de:f90d
1362c19:dd:d9:dd:c25:c25:94de:f90e/1272c19:dd:d9:dd:c25:c25:94de:f90f
1372c19:dd:d9:dd:c25:c25:94de:f910/1272c19:dd:d9:dd:c25:c25:94de:f911
1382c19:dd:d9:dd:c25:c25:94de:f912/1272c19:dd:d9:dd:c25:c25:94de:f913
1392c19:dd:d9:dd:c25:c25:94de:f914/1272c19:dd:d9:dd:c25:c25:94de:f915
1402c19:dd:d9:dd:c25:c25:94de:f916/1272c19:dd:d9:dd:c25:c25:94de:f917
1412c19:dd:d9:dd:c25:c25:94de:f918/1272c19:dd:d9:dd:c25:c25:94de:f919
1422c19:dd:d9:dd:c25:c25:94de:f91a/1272c19:dd:d9:dd:c25:c25:94de:f91b
1432c19:dd:d9:dd:c25:c25:94de:f91c/1272c19:dd:d9:dd:c25:c25:94de:f91d
1442c19:dd:d9:dd:c25:c25:94de:f91e/1272c19:dd:d9:dd:c25:c25:94de:f91f
1452c19:dd:d9:dd:c25:c25:94de:f920/1272c19:dd:d9:dd:c25:c25:94de:f921
1462c19:dd:d9:dd:c25:c25:94de:f922/1272c19:dd:d9:dd:c25:c25:94de:f923
1472c19:dd:d9:dd:c25:c25:94de:f924/1272c19:dd:d9:dd:c25:c25:94de:f925
1482c19:dd:d9:dd:c25:c25:94de:f926/1272c19:dd:d9:dd:c25:c25:94de:f927
1492c19:dd:d9:dd:c25:c25:94de:f928/1272c19:dd:d9:dd:c25:c25:94de:f929
1502c19:dd:d9:dd:c25:c25:94de:f92a/1272c19:dd:d9:dd:c25:c25:94de:f92b
1512c19:dd:d9:dd:c25:c25:94de:f92c/1272c19:dd:d9:dd:c25:c25:94de:f92d
1522c19:dd:d9:dd:c25:c25:94de:f92e/1272c19:dd:d9:dd:c25:c25:94de:f92f
1532c19:dd:d9:dd:c25:c25:94de:f930/1272c19:dd:d9:dd:c25:c25:94de:f931
1542c19:dd:d9:dd:c25:c25:94de:f932/1272c19:dd:d9:dd:c25:c25:94de:f933
1552c19:dd:d9:dd:c25:c25:94de:f934/1272c19:dd:d9:dd:c25:c25:94de:f935
1562c19:dd:d9:dd:c25:c25:94de:f936/1272c19:dd:d9:dd:c25:c25:94de:f937
1572c19:dd:d9:dd:c25:c25:94de:f938/1272c19:dd:d9:dd:c25:c25:94de:f939
1582c19:dd:d9:dd:c25:c25:94de:f93a/1272c19:dd:d9:dd:c25:c25:94de:f93b
1592c19:dd:d9:dd:c25:c25:94de:f93c/1272c19:dd:d9:dd:c25:c25:94de:f93d
1602c19:dd:d9:dd:c25:c25:94de:f93e/1272c19:dd:d9:dd:c25:c25:94de:f93f
1612c19:dd:d9:dd:c25:c25:94de:f940/1272c19:dd:d9:dd:c25:c25:94de:f941
1622c19:dd:d9:dd:c25:c25:94de:f942/1272c19:dd:d9:dd:c25:c25:94de:f943
1632c19:dd:d9:dd:c25:c25:94de:f944/1272c19:dd:d9:dd:c25:c25:94de:f945
1642c19:dd:d9:dd:c25:c25:94de:f946/1272c19:dd:d9:dd:c25:c25:94de:f947
1652c19:dd:d9:dd:c25:c25:94de:f948/1272c19:dd:d9:dd:c25:c25:94de:f949
1662c19:dd:d9:dd:c25:c25:94de:f94a/1272c19:dd:d9:dd:c25:c25:94de:f94b
1672c19:dd:d9:dd:c25:c25:94de:f94c/1272c19:dd:d9:dd:c25:c25:94de:f94d
1682c19:dd:d9:dd:c25:c25:94de:f94e/1272c19:dd:d9:dd:c25:c25:94de:f94f
1692c19:dd:d9:dd:c25:c25:94de:f950/1272c19:dd:d9:dd:c25:c25:94de:f951
1702c19:dd:d9:dd:c25:c25:94de:f952/1272c19:dd:d9:dd:c25:c25:94de:f953
1712c19:dd:d9:dd:c25:c25:94de:f954/1272c19:dd:d9:dd:c25:c25:94de:f955
1722c19:dd:d9:dd:c25:c25:94de:f956/1272c19:dd:d9:dd:c25:c25:94de:f957
1732c19:dd:d9:dd:c25:c25:94de:f958/1272c19:dd:d9:dd:c25:c25:94de:f959
1742c19:dd:d9:dd:c25:c25:94de:f95a/1272c19:dd:d9:dd:c25:c25:94de:f95b
1752c19:dd:d9:dd:c25:c25:94de:f95c/1272c19:dd:d9:dd:c25:c25:94de:f95d
1762c19:dd:d9:dd:c25:c25:94de:f95e/1272c19:dd:d9:dd:c25:c25:94de:f95f
1772c19:dd:d9:dd:c25:c25:94de:f960/1272c19:dd:d9:dd:c25:c25:94de:f961
1782c19:dd:d9:dd:c25:c25:94de:f962/1272c19:dd:d9:dd:c25:c25:94de:f963
1792c19:dd:d9:dd:c25:c25:94de:f964/1272c19:dd:d9:dd:c25:c25:94de:f965
1802c19:dd:d9:dd:c25:c25:94de:f966/1272c19:dd:d9:dd:c25:c25:94de:f967
1812c19:dd:d9:dd:c25:c25:94de:f968/1272c19:dd:d9:dd:c25:c25:94de:f969
1822c19:dd:d9:dd:c25:c25:94de:f96a/1272c19:dd:d9:dd:c25:c25:94de:f96b
1832c19:dd:d9:dd:c25:c25:94de:f96c/1272c19:dd:d9:dd:c25:c25:94de:f96d
1842c19:dd:d9:dd:c25:c25:94de:f96e/1272c19:dd:d9:dd:c25:c25:94de:f96f
1852c19:dd:d9:dd:c25:c25:94de:f970/1272c19:dd:d9:dd:c25:c25:94de:f971
1862c19:dd:d9:dd:c25:c25:94de:f972/1272c19:dd:d9:dd:c25:c25:94de:f973
1872c19:dd:d9:dd:c25:c25:94de:f974/1272c19:dd:d9:dd:c25:c25:94de:f975
1882c19:dd:d9:dd:c25:c25:94de:f976/1272c19:dd:d9:dd:c25:c25:94de:f977
1892c19:dd:d9:dd:c25:c25:94de:f978/1272c19:dd:d9:dd:c25:c25:94de:f979
1902c19:dd:d9:dd:c25:c25:94de:f97a/1272c19:dd:d9:dd:c25:c25:94de:f97b
1912c19:dd:d9:dd:c25:c25:94de:f97c/1272c19:dd:d9:dd:c25:c25:94de:f97d
1922c19:dd:d9:dd:c25:c25:94de:f97e/1272c19:dd:d9:dd:c25:c25:94de:f97f
1932c19:dd:d9:dd:c25:c25:94de:f980/1272c19:dd:d9:dd:c25:c25:94de:f981
1942c19:dd:d9:dd:c25:c25:94de:f982/1272c19:dd:d9:dd:c25:c25:94de:f983
1952c19:dd:d9:dd:c25:c25:94de:f984/1272c19:dd:d9:dd:c25:c25:94de:f985
1962c19:dd:d9:dd:c25:c25:94de:f986/1272c19:dd:d9:dd:c25:c25:94de:f987
1972c19:dd:d9:dd:c25:c25:94de:f988/1272c19:dd:d9:dd:c25:c25:94de:f989
1982c19:dd:d9:dd:c25:c25:94de:f98a/1272c19:dd:d9:dd:c25:c25:94de:f98b
1992c19:dd:d9:dd:c25:c25:94de:f98c/1272c19:dd:d9:dd:c25:c25:94de:f98d
2002c19:dd:d9:dd:c25:c25:94de:f98e/1272c19:dd:d9:dd:c25:c25:94de:f98f
2012c19:dd:d9:dd:c25:c25:94de:f990/1272c19:dd:d9:dd:c25:c25:94de:f991
2022c19:dd:d9:dd:c25:c25:94de:f992/1272c19:dd:d9:dd:c25:c25:94de:f993
2032c19:dd:d9:dd:c25:c25:94de:f994/1272c19:dd:d9:dd:c25:c25:94de:f995
2042c19:dd:d9:dd:c25:c25:94de:f996/1272c19:dd:d9:dd:c25:c25:94de:f997
2052c19:dd:d9:dd:c25:c25:94de:f998/1272c19:dd:d9:dd:c25:c25:94de:f999
2062c19:dd:d9:dd:c25:c25:94de:f99a/1272c19:dd:d9:dd:c25:c25:94de:f99b
2072c19:dd:d9:dd:c25:c25:94de:f99c/1272c19:dd:d9:dd:c25:c25:94de:f99d
2082c19:dd:d9:dd:c25:c25:94de:f99e/1272c19:dd:d9:dd:c25:c25:94de:f99f
2092c19:dd:d9:dd:c25:c25:94de:f9a0/1272c19:dd:d9:dd:c25:c25:94de:f9a1
2102c19:dd:d9:dd:c25:c25:94de:f9a2/1272c19:dd:d9:dd:c25:c25:94de:f9a3
2112c19:dd:d9:dd:c25:c25:94de:f9a4/1272c19:dd:d9:dd:c25:c25:94de:f9a5
2122c19:dd:d9:dd:c25:c25:94de:f9a6/1272c19:dd:d9:dd:c25:c25:94de:f9a7
2132c19:dd:d9:dd:c25:c25:94de:f9a8/1272c19:dd:d9:dd:c25:c25:94de:f9a9
2142c19:dd:d9:dd:c25:c25:94de:f9aa/1272c19:dd:d9:dd:c25:c25:94de:f9ab
2152c19:dd:d9:dd:c25:c25:94de:f9ac/1272c19:dd:d9:dd:c25:c25:94de:f9ad
2162c19:dd:d9:dd:c25:c25:94de:f9ae/1272c19:dd:d9:dd:c25:c25:94de:f9af
2172c19:dd:d9:dd:c25:c25:94de:f9b0/1272c19:dd:d9:dd:c25:c25:94de:f9b1
2182c19:dd:d9:dd:c25:c25:94de:f9b2/1272c19:dd:d9:dd:c25:c25:94de:f9b3
2192c19:dd:d9:dd:c25:c25:94de:f9b4/1272c19:dd:d9:dd:c25:c25:94de:f9b5
2202c19:dd:d9:dd:c25:c25:94de:f9b6/1272c19:dd:d9:dd:c25:c25:94de:f9b7
2212c19:dd:d9:dd:c25:c25:94de:f9b8/1272c19:dd:d9:dd:c25:c25:94de:f9b9
2222c19:dd:d9:dd:c25:c25:94de:f9ba/1272c19:dd:d9:dd:c25:c25:94de:f9bb
2232c19:dd:d9:dd:c25:c25:94de:f9bc/1272c19:dd:d9:dd:c25:c25:94de:f9bd
2242c19:dd:d9:dd:c25:c25:94de:f9be/1272c19:dd:d9:dd:c25:c25:94de:f9bf
2252c19:dd:d9:dd:c25:c25:94de:f9c0/1272c19:dd:d9:dd:c25:c25:94de:f9c1
2262c19:dd:d9:dd:c25:c25:94de:f9c2/1272c19:dd:d9:dd:c25:c25:94de:f9c3
2272c19:dd:d9:dd:c25:c25:94de:f9c4/1272c19:dd:d9:dd:c25:c25:94de:f9c5
2282c19:dd:d9:dd:c25:c25:94de:f9c6/1272c19:dd:d9:dd:c25:c25:94de:f9c7
2292c19:dd:d9:dd:c25:c25:94de:f9c8/1272c19:dd:d9:dd:c25:c25:94de:f9c9
2302c19:dd:d9:dd:c25:c25:94de:f9ca/1272c19:dd:d9:dd:c25:c25:94de:f9cb
2312c19:dd:d9:dd:c25:c25:94de:f9cc/1272c19:dd:d9:dd:c25:c25:94de:f9cd
2322c19:dd:d9:dd:c25:c25:94de:f9ce/1272c19:dd:d9:dd:c25:c25:94de:f9cf
2332c19:dd:d9:dd:c25:c25:94de:f9d0/1272c19:dd:d9:dd:c25:c25:94de:f9d1
2342c19:dd:d9:dd:c25:c25:94de:f9d2/1272c19:dd:d9:dd:c25:c25:94de:f9d3
2352c19:dd:d9:dd:c25:c25:94de:f9d4/1272c19:dd:d9:dd:c25:c25:94de:f9d5
2362c19:dd:d9:dd:c25:c25:94de:f9d6/1272c19:dd:d9:dd:c25:c25:94de:f9d7
2372c19:dd:d9:dd:c25:c25:94de:f9d8/1272c19:dd:d9:dd:c25:c25:94de:f9d9
2382c19:dd:d9:dd:c25:c25:94de:f9da/1272c19:dd:d9:dd:c25:c25:94de:f9db
2392c19:dd:d9:dd:c25:c25:94de:f9dc/1272c19:dd:d9:dd:c25:c25:94de:f9dd
2402c19:dd:d9:dd:c25:c25:94de:f9de/1272c19:dd:d9:dd:c25:c25:94de:f9df
2412c19:dd:d9:dd:c25:c25:94de:f9e0/1272c19:dd:d9:dd:c25:c25:94de:f9e1
2422c19:dd:d9:dd:c25:c25:94de:f9e2/1272c19:dd:d9:dd:c25:c25:94de:f9e3
2432c19:dd:d9:dd:c25:c25:94de:f9e4/1272c19:dd:d9:dd:c25:c25:94de:f9e5
2442c19:dd:d9:dd:c25:c25:94de:f9e6/1272c19:dd:d9:dd:c25:c25:94de:f9e7
2452c19:dd:d9:dd:c25:c25:94de:f9e8/1272c19:dd:d9:dd:c25:c25:94de:f9e9
2462c19:dd:d9:dd:c25:c25:94de:f9ea/1272c19:dd:d9:dd:c25:c25:94de:f9eb
2472c19:dd:d9:dd:c25:c25:94de:f9ec/1272c19:dd:d9:dd:c25:c25:94de:f9ed
2482c19:dd:d9:dd:c25:c25:94de:f9ee/1272c19:dd:d9:dd:c25:c25:94de:f9ef
2492c19:dd:d9:dd:c25:c25:94de:f9f0/1272c19:dd:d9:dd:c25:c25:94de:f9f1
2502c19:dd:d9:dd:c25:c25:94de:f9f2/1272c19:dd:d9:dd:c25:c25:94de:f9f3
2512c19:dd:d9:dd:c25:c25:94de:f9f4/1272c19:dd:d9:dd:c25:c25:94de:f9f5
2522c19:dd:d9:dd:c25:c25:94de:f9f6/1272c19:dd:d9:dd:c25:c25:94de:f9f7
2532c19:dd:d9:dd:c25:c25:94de:f9f8/1272c19:dd:d9:dd:c25:c25:94de:f9f9
2542c19:dd:d9:dd:c25:c25:94de:f9fa/1272c19:dd:d9:dd:c25:c25:94de:f9fb
2552c19:dd:d9:dd:c25:c25:94de:f9fc/1272c19:dd:d9:dd:c25:c25:94de:f9fd
2562c19:dd:d9:dd:c25:c25:94de:f9fe/1272c19:dd:d9:dd:c25:c25:94de:f9ff

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.