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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:c800/117
First address
2c19:dd:c25:c25d:dd:dd:dd:c800
Last address
2c19:dd:c25:c25d:dd:dd:dd:cfff
Addresses
2,048
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:c800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
8.c.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.c.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.c.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.c.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.c.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.c.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.c.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.c.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:c800/117 makes 1,024 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:c800/1272c19:dd:c25:c25d:dd:dd:dd:c801
22c19:dd:c25:c25d:dd:dd:dd:c802/1272c19:dd:c25:c25d:dd:dd:dd:c803
32c19:dd:c25:c25d:dd:dd:dd:c804/1272c19:dd:c25:c25d:dd:dd:dd:c805
42c19:dd:c25:c25d:dd:dd:dd:c806/1272c19:dd:c25:c25d:dd:dd:dd:c807
52c19:dd:c25:c25d:dd:dd:dd:c808/1272c19:dd:c25:c25d:dd:dd:dd:c809
62c19:dd:c25:c25d:dd:dd:dd:c80a/1272c19:dd:c25:c25d:dd:dd:dd:c80b
72c19:dd:c25:c25d:dd:dd:dd:c80c/1272c19:dd:c25:c25d:dd:dd:dd:c80d
82c19:dd:c25:c25d:dd:dd:dd:c80e/1272c19:dd:c25:c25d:dd:dd:dd:c80f
92c19:dd:c25:c25d:dd:dd:dd:c810/1272c19:dd:c25:c25d:dd:dd:dd:c811
102c19:dd:c25:c25d:dd:dd:dd:c812/1272c19:dd:c25:c25d:dd:dd:dd:c813
112c19:dd:c25:c25d:dd:dd:dd:c814/1272c19:dd:c25:c25d:dd:dd:dd:c815
122c19:dd:c25:c25d:dd:dd:dd:c816/1272c19:dd:c25:c25d:dd:dd:dd:c817
132c19:dd:c25:c25d:dd:dd:dd:c818/1272c19:dd:c25:c25d:dd:dd:dd:c819
142c19:dd:c25:c25d:dd:dd:dd:c81a/1272c19:dd:c25:c25d:dd:dd:dd:c81b
152c19:dd:c25:c25d:dd:dd:dd:c81c/1272c19:dd:c25:c25d:dd:dd:dd:c81d
162c19:dd:c25:c25d:dd:dd:dd:c81e/1272c19:dd:c25:c25d:dd:dd:dd:c81f
172c19:dd:c25:c25d:dd:dd:dd:c820/1272c19:dd:c25:c25d:dd:dd:dd:c821
182c19:dd:c25:c25d:dd:dd:dd:c822/1272c19:dd:c25:c25d:dd:dd:dd:c823
192c19:dd:c25:c25d:dd:dd:dd:c824/1272c19:dd:c25:c25d:dd:dd:dd:c825
202c19:dd:c25:c25d:dd:dd:dd:c826/1272c19:dd:c25:c25d:dd:dd:dd:c827
212c19:dd:c25:c25d:dd:dd:dd:c828/1272c19:dd:c25:c25d:dd:dd:dd:c829
222c19:dd:c25:c25d:dd:dd:dd:c82a/1272c19:dd:c25:c25d:dd:dd:dd:c82b
232c19:dd:c25:c25d:dd:dd:dd:c82c/1272c19:dd:c25:c25d:dd:dd:dd:c82d
242c19:dd:c25:c25d:dd:dd:dd:c82e/1272c19:dd:c25:c25d:dd:dd:dd:c82f
252c19:dd:c25:c25d:dd:dd:dd:c830/1272c19:dd:c25:c25d:dd:dd:dd:c831
262c19:dd:c25:c25d:dd:dd:dd:c832/1272c19:dd:c25:c25d:dd:dd:dd:c833
272c19:dd:c25:c25d:dd:dd:dd:c834/1272c19:dd:c25:c25d:dd:dd:dd:c835
282c19:dd:c25:c25d:dd:dd:dd:c836/1272c19:dd:c25:c25d:dd:dd:dd:c837
292c19:dd:c25:c25d:dd:dd:dd:c838/1272c19:dd:c25:c25d:dd:dd:dd:c839
302c19:dd:c25:c25d:dd:dd:dd:c83a/1272c19:dd:c25:c25d:dd:dd:dd:c83b
312c19:dd:c25:c25d:dd:dd:dd:c83c/1272c19:dd:c25:c25d:dd:dd:dd:c83d
322c19:dd:c25:c25d:dd:dd:dd:c83e/1272c19:dd:c25:c25d:dd:dd:dd:c83f
332c19:dd:c25:c25d:dd:dd:dd:c840/1272c19:dd:c25:c25d:dd:dd:dd:c841
342c19:dd:c25:c25d:dd:dd:dd:c842/1272c19:dd:c25:c25d:dd:dd:dd:c843
352c19:dd:c25:c25d:dd:dd:dd:c844/1272c19:dd:c25:c25d:dd:dd:dd:c845
362c19:dd:c25:c25d:dd:dd:dd:c846/1272c19:dd:c25:c25d:dd:dd:dd:c847
372c19:dd:c25:c25d:dd:dd:dd:c848/1272c19:dd:c25:c25d:dd:dd:dd:c849
382c19:dd:c25:c25d:dd:dd:dd:c84a/1272c19:dd:c25:c25d:dd:dd:dd:c84b
392c19:dd:c25:c25d:dd:dd:dd:c84c/1272c19:dd:c25:c25d:dd:dd:dd:c84d
402c19:dd:c25:c25d:dd:dd:dd:c84e/1272c19:dd:c25:c25d:dd:dd:dd:c84f
412c19:dd:c25:c25d:dd:dd:dd:c850/1272c19:dd:c25:c25d:dd:dd:dd:c851
422c19:dd:c25:c25d:dd:dd:dd:c852/1272c19:dd:c25:c25d:dd:dd:dd:c853
432c19:dd:c25:c25d:dd:dd:dd:c854/1272c19:dd:c25:c25d:dd:dd:dd:c855
442c19:dd:c25:c25d:dd:dd:dd:c856/1272c19:dd:c25:c25d:dd:dd:dd:c857
452c19:dd:c25:c25d:dd:dd:dd:c858/1272c19:dd:c25:c25d:dd:dd:dd:c859
462c19:dd:c25:c25d:dd:dd:dd:c85a/1272c19:dd:c25:c25d:dd:dd:dd:c85b
472c19:dd:c25:c25d:dd:dd:dd:c85c/1272c19:dd:c25:c25d:dd:dd:dd:c85d
482c19:dd:c25:c25d:dd:dd:dd:c85e/1272c19:dd:c25:c25d:dd:dd:dd:c85f
492c19:dd:c25:c25d:dd:dd:dd:c860/1272c19:dd:c25:c25d:dd:dd:dd:c861
502c19:dd:c25:c25d:dd:dd:dd:c862/1272c19:dd:c25:c25d:dd:dd:dd:c863
512c19:dd:c25:c25d:dd:dd:dd:c864/1272c19:dd:c25:c25d:dd:dd:dd:c865
522c19:dd:c25:c25d:dd:dd:dd:c866/1272c19:dd:c25:c25d:dd:dd:dd:c867
532c19:dd:c25:c25d:dd:dd:dd:c868/1272c19:dd:c25:c25d:dd:dd:dd:c869
542c19:dd:c25:c25d:dd:dd:dd:c86a/1272c19:dd:c25:c25d:dd:dd:dd:c86b
552c19:dd:c25:c25d:dd:dd:dd:c86c/1272c19:dd:c25:c25d:dd:dd:dd:c86d
562c19:dd:c25:c25d:dd:dd:dd:c86e/1272c19:dd:c25:c25d:dd:dd:dd:c86f
572c19:dd:c25:c25d:dd:dd:dd:c870/1272c19:dd:c25:c25d:dd:dd:dd:c871
582c19:dd:c25:c25d:dd:dd:dd:c872/1272c19:dd:c25:c25d:dd:dd:dd:c873
592c19:dd:c25:c25d:dd:dd:dd:c874/1272c19:dd:c25:c25d:dd:dd:dd:c875
602c19:dd:c25:c25d:dd:dd:dd:c876/1272c19:dd:c25:c25d:dd:dd:dd:c877
612c19:dd:c25:c25d:dd:dd:dd:c878/1272c19:dd:c25:c25d:dd:dd:dd:c879
622c19:dd:c25:c25d:dd:dd:dd:c87a/1272c19:dd:c25:c25d:dd:dd:dd:c87b
632c19:dd:c25:c25d:dd:dd:dd:c87c/1272c19:dd:c25:c25d:dd:dd:dd:c87d
642c19:dd:c25:c25d:dd:dd:dd:c87e/1272c19:dd:c25:c25d:dd:dd:dd:c87f
652c19:dd:c25:c25d:dd:dd:dd:c880/1272c19:dd:c25:c25d:dd:dd:dd:c881
662c19:dd:c25:c25d:dd:dd:dd:c882/1272c19:dd:c25:c25d:dd:dd:dd:c883
672c19:dd:c25:c25d:dd:dd:dd:c884/1272c19:dd:c25:c25d:dd:dd:dd:c885
682c19:dd:c25:c25d:dd:dd:dd:c886/1272c19:dd:c25:c25d:dd:dd:dd:c887
692c19:dd:c25:c25d:dd:dd:dd:c888/1272c19:dd:c25:c25d:dd:dd:dd:c889
702c19:dd:c25:c25d:dd:dd:dd:c88a/1272c19:dd:c25:c25d:dd:dd:dd:c88b
712c19:dd:c25:c25d:dd:dd:dd:c88c/1272c19:dd:c25:c25d:dd:dd:dd:c88d
722c19:dd:c25:c25d:dd:dd:dd:c88e/1272c19:dd:c25:c25d:dd:dd:dd:c88f
732c19:dd:c25:c25d:dd:dd:dd:c890/1272c19:dd:c25:c25d:dd:dd:dd:c891
742c19:dd:c25:c25d:dd:dd:dd:c892/1272c19:dd:c25:c25d:dd:dd:dd:c893
752c19:dd:c25:c25d:dd:dd:dd:c894/1272c19:dd:c25:c25d:dd:dd:dd:c895
762c19:dd:c25:c25d:dd:dd:dd:c896/1272c19:dd:c25:c25d:dd:dd:dd:c897
772c19:dd:c25:c25d:dd:dd:dd:c898/1272c19:dd:c25:c25d:dd:dd:dd:c899
782c19:dd:c25:c25d:dd:dd:dd:c89a/1272c19:dd:c25:c25d:dd:dd:dd:c89b
792c19:dd:c25:c25d:dd:dd:dd:c89c/1272c19:dd:c25:c25d:dd:dd:dd:c89d
802c19:dd:c25:c25d:dd:dd:dd:c89e/1272c19:dd:c25:c25d:dd:dd:dd:c89f
812c19:dd:c25:c25d:dd:dd:dd:c8a0/1272c19:dd:c25:c25d:dd:dd:dd:c8a1
822c19:dd:c25:c25d:dd:dd:dd:c8a2/1272c19:dd:c25:c25d:dd:dd:dd:c8a3
832c19:dd:c25:c25d:dd:dd:dd:c8a4/1272c19:dd:c25:c25d:dd:dd:dd:c8a5
842c19:dd:c25:c25d:dd:dd:dd:c8a6/1272c19:dd:c25:c25d:dd:dd:dd:c8a7
852c19:dd:c25:c25d:dd:dd:dd:c8a8/1272c19:dd:c25:c25d:dd:dd:dd:c8a9
862c19:dd:c25:c25d:dd:dd:dd:c8aa/1272c19:dd:c25:c25d:dd:dd:dd:c8ab
872c19:dd:c25:c25d:dd:dd:dd:c8ac/1272c19:dd:c25:c25d:dd:dd:dd:c8ad
882c19:dd:c25:c25d:dd:dd:dd:c8ae/1272c19:dd:c25:c25d:dd:dd:dd:c8af
892c19:dd:c25:c25d:dd:dd:dd:c8b0/1272c19:dd:c25:c25d:dd:dd:dd:c8b1
902c19:dd:c25:c25d:dd:dd:dd:c8b2/1272c19:dd:c25:c25d:dd:dd:dd:c8b3
912c19:dd:c25:c25d:dd:dd:dd:c8b4/1272c19:dd:c25:c25d:dd:dd:dd:c8b5
922c19:dd:c25:c25d:dd:dd:dd:c8b6/1272c19:dd:c25:c25d:dd:dd:dd:c8b7
932c19:dd:c25:c25d:dd:dd:dd:c8b8/1272c19:dd:c25:c25d:dd:dd:dd:c8b9
942c19:dd:c25:c25d:dd:dd:dd:c8ba/1272c19:dd:c25:c25d:dd:dd:dd:c8bb
952c19:dd:c25:c25d:dd:dd:dd:c8bc/1272c19:dd:c25:c25d:dd:dd:dd:c8bd
962c19:dd:c25:c25d:dd:dd:dd:c8be/1272c19:dd:c25:c25d:dd:dd:dd:c8bf
972c19:dd:c25:c25d:dd:dd:dd:c8c0/1272c19:dd:c25:c25d:dd:dd:dd:c8c1
982c19:dd:c25:c25d:dd:dd:dd:c8c2/1272c19:dd:c25:c25d:dd:dd:dd:c8c3
992c19:dd:c25:c25d:dd:dd:dd:c8c4/1272c19:dd:c25:c25d:dd:dd:dd:c8c5
1002c19:dd:c25:c25d:dd:dd:dd:c8c6/1272c19:dd:c25:c25d:dd:dd:dd:c8c7
1012c19:dd:c25:c25d:dd:dd:dd:c8c8/1272c19:dd:c25:c25d:dd:dd:dd:c8c9
1022c19:dd:c25:c25d:dd:dd:dd:c8ca/1272c19:dd:c25:c25d:dd:dd:dd:c8cb
1032c19:dd:c25:c25d:dd:dd:dd:c8cc/1272c19:dd:c25:c25d:dd:dd:dd:c8cd
1042c19:dd:c25:c25d:dd:dd:dd:c8ce/1272c19:dd:c25:c25d:dd:dd:dd:c8cf
1052c19:dd:c25:c25d:dd:dd:dd:c8d0/1272c19:dd:c25:c25d:dd:dd:dd:c8d1
1062c19:dd:c25:c25d:dd:dd:dd:c8d2/1272c19:dd:c25:c25d:dd:dd:dd:c8d3
1072c19:dd:c25:c25d:dd:dd:dd:c8d4/1272c19:dd:c25:c25d:dd:dd:dd:c8d5
1082c19:dd:c25:c25d:dd:dd:dd:c8d6/1272c19:dd:c25:c25d:dd:dd:dd:c8d7
1092c19:dd:c25:c25d:dd:dd:dd:c8d8/1272c19:dd:c25:c25d:dd:dd:dd:c8d9
1102c19:dd:c25:c25d:dd:dd:dd:c8da/1272c19:dd:c25:c25d:dd:dd:dd:c8db
1112c19:dd:c25:c25d:dd:dd:dd:c8dc/1272c19:dd:c25:c25d:dd:dd:dd:c8dd
1122c19:dd:c25:c25d:dd:dd:dd:c8de/1272c19:dd:c25:c25d:dd:dd:dd:c8df
1132c19:dd:c25:c25d:dd:dd:dd:c8e0/1272c19:dd:c25:c25d:dd:dd:dd:c8e1
1142c19:dd:c25:c25d:dd:dd:dd:c8e2/1272c19:dd:c25:c25d:dd:dd:dd:c8e3
1152c19:dd:c25:c25d:dd:dd:dd:c8e4/1272c19:dd:c25:c25d:dd:dd:dd:c8e5
1162c19:dd:c25:c25d:dd:dd:dd:c8e6/1272c19:dd:c25:c25d:dd:dd:dd:c8e7
1172c19:dd:c25:c25d:dd:dd:dd:c8e8/1272c19:dd:c25:c25d:dd:dd:dd:c8e9
1182c19:dd:c25:c25d:dd:dd:dd:c8ea/1272c19:dd:c25:c25d:dd:dd:dd:c8eb
1192c19:dd:c25:c25d:dd:dd:dd:c8ec/1272c19:dd:c25:c25d:dd:dd:dd:c8ed
1202c19:dd:c25:c25d:dd:dd:dd:c8ee/1272c19:dd:c25:c25d:dd:dd:dd:c8ef
1212c19:dd:c25:c25d:dd:dd:dd:c8f0/1272c19:dd:c25:c25d:dd:dd:dd:c8f1
1222c19:dd:c25:c25d:dd:dd:dd:c8f2/1272c19:dd:c25:c25d:dd:dd:dd:c8f3
1232c19:dd:c25:c25d:dd:dd:dd:c8f4/1272c19:dd:c25:c25d:dd:dd:dd:c8f5
1242c19:dd:c25:c25d:dd:dd:dd:c8f6/1272c19:dd:c25:c25d:dd:dd:dd:c8f7
1252c19:dd:c25:c25d:dd:dd:dd:c8f8/1272c19:dd:c25:c25d:dd:dd:dd:c8f9
1262c19:dd:c25:c25d:dd:dd:dd:c8fa/1272c19:dd:c25:c25d:dd:dd:dd:c8fb
1272c19:dd:c25:c25d:dd:dd:dd:c8fc/1272c19:dd:c25:c25d:dd:dd:dd:c8fd
1282c19:dd:c25:c25d:dd:dd:dd:c8fe/1272c19:dd:c25:c25d:dd:dd:dd:c8ff
1292c19:dd:c25:c25d:dd:dd:dd:c900/1272c19:dd:c25:c25d:dd:dd:dd:c901
1302c19:dd:c25:c25d:dd:dd:dd:c902/1272c19:dd:c25:c25d:dd:dd:dd:c903
1312c19:dd:c25:c25d:dd:dd:dd:c904/1272c19:dd:c25:c25d:dd:dd:dd:c905
1322c19:dd:c25:c25d:dd:dd:dd:c906/1272c19:dd:c25:c25d:dd:dd:dd:c907
1332c19:dd:c25:c25d:dd:dd:dd:c908/1272c19:dd:c25:c25d:dd:dd:dd:c909
1342c19:dd:c25:c25d:dd:dd:dd:c90a/1272c19:dd:c25:c25d:dd:dd:dd:c90b
1352c19:dd:c25:c25d:dd:dd:dd:c90c/1272c19:dd:c25:c25d:dd:dd:dd:c90d
1362c19:dd:c25:c25d:dd:dd:dd:c90e/1272c19:dd:c25:c25d:dd:dd:dd:c90f
1372c19:dd:c25:c25d:dd:dd:dd:c910/1272c19:dd:c25:c25d:dd:dd:dd:c911
1382c19:dd:c25:c25d:dd:dd:dd:c912/1272c19:dd:c25:c25d:dd:dd:dd:c913
1392c19:dd:c25:c25d:dd:dd:dd:c914/1272c19:dd:c25:c25d:dd:dd:dd:c915
1402c19:dd:c25:c25d:dd:dd:dd:c916/1272c19:dd:c25:c25d:dd:dd:dd:c917
1412c19:dd:c25:c25d:dd:dd:dd:c918/1272c19:dd:c25:c25d:dd:dd:dd:c919
1422c19:dd:c25:c25d:dd:dd:dd:c91a/1272c19:dd:c25:c25d:dd:dd:dd:c91b
1432c19:dd:c25:c25d:dd:dd:dd:c91c/1272c19:dd:c25:c25d:dd:dd:dd:c91d
1442c19:dd:c25:c25d:dd:dd:dd:c91e/1272c19:dd:c25:c25d:dd:dd:dd:c91f
1452c19:dd:c25:c25d:dd:dd:dd:c920/1272c19:dd:c25:c25d:dd:dd:dd:c921
1462c19:dd:c25:c25d:dd:dd:dd:c922/1272c19:dd:c25:c25d:dd:dd:dd:c923
1472c19:dd:c25:c25d:dd:dd:dd:c924/1272c19:dd:c25:c25d:dd:dd:dd:c925
1482c19:dd:c25:c25d:dd:dd:dd:c926/1272c19:dd:c25:c25d:dd:dd:dd:c927
1492c19:dd:c25:c25d:dd:dd:dd:c928/1272c19:dd:c25:c25d:dd:dd:dd:c929
1502c19:dd:c25:c25d:dd:dd:dd:c92a/1272c19:dd:c25:c25d:dd:dd:dd:c92b
1512c19:dd:c25:c25d:dd:dd:dd:c92c/1272c19:dd:c25:c25d:dd:dd:dd:c92d
1522c19:dd:c25:c25d:dd:dd:dd:c92e/1272c19:dd:c25:c25d:dd:dd:dd:c92f
1532c19:dd:c25:c25d:dd:dd:dd:c930/1272c19:dd:c25:c25d:dd:dd:dd:c931
1542c19:dd:c25:c25d:dd:dd:dd:c932/1272c19:dd:c25:c25d:dd:dd:dd:c933
1552c19:dd:c25:c25d:dd:dd:dd:c934/1272c19:dd:c25:c25d:dd:dd:dd:c935
1562c19:dd:c25:c25d:dd:dd:dd:c936/1272c19:dd:c25:c25d:dd:dd:dd:c937
1572c19:dd:c25:c25d:dd:dd:dd:c938/1272c19:dd:c25:c25d:dd:dd:dd:c939
1582c19:dd:c25:c25d:dd:dd:dd:c93a/1272c19:dd:c25:c25d:dd:dd:dd:c93b
1592c19:dd:c25:c25d:dd:dd:dd:c93c/1272c19:dd:c25:c25d:dd:dd:dd:c93d
1602c19:dd:c25:c25d:dd:dd:dd:c93e/1272c19:dd:c25:c25d:dd:dd:dd:c93f
1612c19:dd:c25:c25d:dd:dd:dd:c940/1272c19:dd:c25:c25d:dd:dd:dd:c941
1622c19:dd:c25:c25d:dd:dd:dd:c942/1272c19:dd:c25:c25d:dd:dd:dd:c943
1632c19:dd:c25:c25d:dd:dd:dd:c944/1272c19:dd:c25:c25d:dd:dd:dd:c945
1642c19:dd:c25:c25d:dd:dd:dd:c946/1272c19:dd:c25:c25d:dd:dd:dd:c947
1652c19:dd:c25:c25d:dd:dd:dd:c948/1272c19:dd:c25:c25d:dd:dd:dd:c949
1662c19:dd:c25:c25d:dd:dd:dd:c94a/1272c19:dd:c25:c25d:dd:dd:dd:c94b
1672c19:dd:c25:c25d:dd:dd:dd:c94c/1272c19:dd:c25:c25d:dd:dd:dd:c94d
1682c19:dd:c25:c25d:dd:dd:dd:c94e/1272c19:dd:c25:c25d:dd:dd:dd:c94f
1692c19:dd:c25:c25d:dd:dd:dd:c950/1272c19:dd:c25:c25d:dd:dd:dd:c951
1702c19:dd:c25:c25d:dd:dd:dd:c952/1272c19:dd:c25:c25d:dd:dd:dd:c953
1712c19:dd:c25:c25d:dd:dd:dd:c954/1272c19:dd:c25:c25d:dd:dd:dd:c955
1722c19:dd:c25:c25d:dd:dd:dd:c956/1272c19:dd:c25:c25d:dd:dd:dd:c957
1732c19:dd:c25:c25d:dd:dd:dd:c958/1272c19:dd:c25:c25d:dd:dd:dd:c959
1742c19:dd:c25:c25d:dd:dd:dd:c95a/1272c19:dd:c25:c25d:dd:dd:dd:c95b
1752c19:dd:c25:c25d:dd:dd:dd:c95c/1272c19:dd:c25:c25d:dd:dd:dd:c95d
1762c19:dd:c25:c25d:dd:dd:dd:c95e/1272c19:dd:c25:c25d:dd:dd:dd:c95f
1772c19:dd:c25:c25d:dd:dd:dd:c960/1272c19:dd:c25:c25d:dd:dd:dd:c961
1782c19:dd:c25:c25d:dd:dd:dd:c962/1272c19:dd:c25:c25d:dd:dd:dd:c963
1792c19:dd:c25:c25d:dd:dd:dd:c964/1272c19:dd:c25:c25d:dd:dd:dd:c965
1802c19:dd:c25:c25d:dd:dd:dd:c966/1272c19:dd:c25:c25d:dd:dd:dd:c967
1812c19:dd:c25:c25d:dd:dd:dd:c968/1272c19:dd:c25:c25d:dd:dd:dd:c969
1822c19:dd:c25:c25d:dd:dd:dd:c96a/1272c19:dd:c25:c25d:dd:dd:dd:c96b
1832c19:dd:c25:c25d:dd:dd:dd:c96c/1272c19:dd:c25:c25d:dd:dd:dd:c96d
1842c19:dd:c25:c25d:dd:dd:dd:c96e/1272c19:dd:c25:c25d:dd:dd:dd:c96f
1852c19:dd:c25:c25d:dd:dd:dd:c970/1272c19:dd:c25:c25d:dd:dd:dd:c971
1862c19:dd:c25:c25d:dd:dd:dd:c972/1272c19:dd:c25:c25d:dd:dd:dd:c973
1872c19:dd:c25:c25d:dd:dd:dd:c974/1272c19:dd:c25:c25d:dd:dd:dd:c975
1882c19:dd:c25:c25d:dd:dd:dd:c976/1272c19:dd:c25:c25d:dd:dd:dd:c977
1892c19:dd:c25:c25d:dd:dd:dd:c978/1272c19:dd:c25:c25d:dd:dd:dd:c979
1902c19:dd:c25:c25d:dd:dd:dd:c97a/1272c19:dd:c25:c25d:dd:dd:dd:c97b
1912c19:dd:c25:c25d:dd:dd:dd:c97c/1272c19:dd:c25:c25d:dd:dd:dd:c97d
1922c19:dd:c25:c25d:dd:dd:dd:c97e/1272c19:dd:c25:c25d:dd:dd:dd:c97f
1932c19:dd:c25:c25d:dd:dd:dd:c980/1272c19:dd:c25:c25d:dd:dd:dd:c981
1942c19:dd:c25:c25d:dd:dd:dd:c982/1272c19:dd:c25:c25d:dd:dd:dd:c983
1952c19:dd:c25:c25d:dd:dd:dd:c984/1272c19:dd:c25:c25d:dd:dd:dd:c985
1962c19:dd:c25:c25d:dd:dd:dd:c986/1272c19:dd:c25:c25d:dd:dd:dd:c987
1972c19:dd:c25:c25d:dd:dd:dd:c988/1272c19:dd:c25:c25d:dd:dd:dd:c989
1982c19:dd:c25:c25d:dd:dd:dd:c98a/1272c19:dd:c25:c25d:dd:dd:dd:c98b
1992c19:dd:c25:c25d:dd:dd:dd:c98c/1272c19:dd:c25:c25d:dd:dd:dd:c98d
2002c19:dd:c25:c25d:dd:dd:dd:c98e/1272c19:dd:c25:c25d:dd:dd:dd:c98f
2012c19:dd:c25:c25d:dd:dd:dd:c990/1272c19:dd:c25:c25d:dd:dd:dd:c991
2022c19:dd:c25:c25d:dd:dd:dd:c992/1272c19:dd:c25:c25d:dd:dd:dd:c993
2032c19:dd:c25:c25d:dd:dd:dd:c994/1272c19:dd:c25:c25d:dd:dd:dd:c995
2042c19:dd:c25:c25d:dd:dd:dd:c996/1272c19:dd:c25:c25d:dd:dd:dd:c997
2052c19:dd:c25:c25d:dd:dd:dd:c998/1272c19:dd:c25:c25d:dd:dd:dd:c999
2062c19:dd:c25:c25d:dd:dd:dd:c99a/1272c19:dd:c25:c25d:dd:dd:dd:c99b
2072c19:dd:c25:c25d:dd:dd:dd:c99c/1272c19:dd:c25:c25d:dd:dd:dd:c99d
2082c19:dd:c25:c25d:dd:dd:dd:c99e/1272c19:dd:c25:c25d:dd:dd:dd:c99f
2092c19:dd:c25:c25d:dd:dd:dd:c9a0/1272c19:dd:c25:c25d:dd:dd:dd:c9a1
2102c19:dd:c25:c25d:dd:dd:dd:c9a2/1272c19:dd:c25:c25d:dd:dd:dd:c9a3
2112c19:dd:c25:c25d:dd:dd:dd:c9a4/1272c19:dd:c25:c25d:dd:dd:dd:c9a5
2122c19:dd:c25:c25d:dd:dd:dd:c9a6/1272c19:dd:c25:c25d:dd:dd:dd:c9a7
2132c19:dd:c25:c25d:dd:dd:dd:c9a8/1272c19:dd:c25:c25d:dd:dd:dd:c9a9
2142c19:dd:c25:c25d:dd:dd:dd:c9aa/1272c19:dd:c25:c25d:dd:dd:dd:c9ab
2152c19:dd:c25:c25d:dd:dd:dd:c9ac/1272c19:dd:c25:c25d:dd:dd:dd:c9ad
2162c19:dd:c25:c25d:dd:dd:dd:c9ae/1272c19:dd:c25:c25d:dd:dd:dd:c9af
2172c19:dd:c25:c25d:dd:dd:dd:c9b0/1272c19:dd:c25:c25d:dd:dd:dd:c9b1
2182c19:dd:c25:c25d:dd:dd:dd:c9b2/1272c19:dd:c25:c25d:dd:dd:dd:c9b3
2192c19:dd:c25:c25d:dd:dd:dd:c9b4/1272c19:dd:c25:c25d:dd:dd:dd:c9b5
2202c19:dd:c25:c25d:dd:dd:dd:c9b6/1272c19:dd:c25:c25d:dd:dd:dd:c9b7
2212c19:dd:c25:c25d:dd:dd:dd:c9b8/1272c19:dd:c25:c25d:dd:dd:dd:c9b9
2222c19:dd:c25:c25d:dd:dd:dd:c9ba/1272c19:dd:c25:c25d:dd:dd:dd:c9bb
2232c19:dd:c25:c25d:dd:dd:dd:c9bc/1272c19:dd:c25:c25d:dd:dd:dd:c9bd
2242c19:dd:c25:c25d:dd:dd:dd:c9be/1272c19:dd:c25:c25d:dd:dd:dd:c9bf
2252c19:dd:c25:c25d:dd:dd:dd:c9c0/1272c19:dd:c25:c25d:dd:dd:dd:c9c1
2262c19:dd:c25:c25d:dd:dd:dd:c9c2/1272c19:dd:c25:c25d:dd:dd:dd:c9c3
2272c19:dd:c25:c25d:dd:dd:dd:c9c4/1272c19:dd:c25:c25d:dd:dd:dd:c9c5
2282c19:dd:c25:c25d:dd:dd:dd:c9c6/1272c19:dd:c25:c25d:dd:dd:dd:c9c7
2292c19:dd:c25:c25d:dd:dd:dd:c9c8/1272c19:dd:c25:c25d:dd:dd:dd:c9c9
2302c19:dd:c25:c25d:dd:dd:dd:c9ca/1272c19:dd:c25:c25d:dd:dd:dd:c9cb
2312c19:dd:c25:c25d:dd:dd:dd:c9cc/1272c19:dd:c25:c25d:dd:dd:dd:c9cd
2322c19:dd:c25:c25d:dd:dd:dd:c9ce/1272c19:dd:c25:c25d:dd:dd:dd:c9cf
2332c19:dd:c25:c25d:dd:dd:dd:c9d0/1272c19:dd:c25:c25d:dd:dd:dd:c9d1
2342c19:dd:c25:c25d:dd:dd:dd:c9d2/1272c19:dd:c25:c25d:dd:dd:dd:c9d3
2352c19:dd:c25:c25d:dd:dd:dd:c9d4/1272c19:dd:c25:c25d:dd:dd:dd:c9d5
2362c19:dd:c25:c25d:dd:dd:dd:c9d6/1272c19:dd:c25:c25d:dd:dd:dd:c9d7
2372c19:dd:c25:c25d:dd:dd:dd:c9d8/1272c19:dd:c25:c25d:dd:dd:dd:c9d9
2382c19:dd:c25:c25d:dd:dd:dd:c9da/1272c19:dd:c25:c25d:dd:dd:dd:c9db
2392c19:dd:c25:c25d:dd:dd:dd:c9dc/1272c19:dd:c25:c25d:dd:dd:dd:c9dd
2402c19:dd:c25:c25d:dd:dd:dd:c9de/1272c19:dd:c25:c25d:dd:dd:dd:c9df
2412c19:dd:c25:c25d:dd:dd:dd:c9e0/1272c19:dd:c25:c25d:dd:dd:dd:c9e1
2422c19:dd:c25:c25d:dd:dd:dd:c9e2/1272c19:dd:c25:c25d:dd:dd:dd:c9e3
2432c19:dd:c25:c25d:dd:dd:dd:c9e4/1272c19:dd:c25:c25d:dd:dd:dd:c9e5
2442c19:dd:c25:c25d:dd:dd:dd:c9e6/1272c19:dd:c25:c25d:dd:dd:dd:c9e7
2452c19:dd:c25:c25d:dd:dd:dd:c9e8/1272c19:dd:c25:c25d:dd:dd:dd:c9e9
2462c19:dd:c25:c25d:dd:dd:dd:c9ea/1272c19:dd:c25:c25d:dd:dd:dd:c9eb
2472c19:dd:c25:c25d:dd:dd:dd:c9ec/1272c19:dd:c25:c25d:dd:dd:dd:c9ed
2482c19:dd:c25:c25d:dd:dd:dd:c9ee/1272c19:dd:c25:c25d:dd:dd:dd:c9ef
2492c19:dd:c25:c25d:dd:dd:dd:c9f0/1272c19:dd:c25:c25d:dd:dd:dd:c9f1
2502c19:dd:c25:c25d:dd:dd:dd:c9f2/1272c19:dd:c25:c25d:dd:dd:dd:c9f3
2512c19:dd:c25:c25d:dd:dd:dd:c9f4/1272c19:dd:c25:c25d:dd:dd:dd:c9f5
2522c19:dd:c25:c25d:dd:dd:dd:c9f6/1272c19:dd:c25:c25d:dd:dd:dd:c9f7
2532c19:dd:c25:c25d:dd:dd:dd:c9f8/1272c19:dd:c25:c25d:dd:dd:dd:c9f9
2542c19:dd:c25:c25d:dd:dd:dd:c9fa/1272c19:dd:c25:c25d:dd:dd:dd:c9fb
2552c19:dd:c25:c25d:dd:dd:dd:c9fc/1272c19:dd:c25:c25d:dd:dd:dd:c9fd
2562c19:dd:c25:c25d:dd:dd:dd:c9fe/1272c19:dd:c25:c25d:dd:dd:dd:c9ff

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.