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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:c25:94de:b800/119
First address
2c19:dd:d9:dd:c25:c25:94de:b800
Last address
2c19:dd:d9:dd:c25:c25:94de:b9ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:b800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
8.b.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.b.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
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/127
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:94de:b800/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:b800/1272c19:dd:d9:dd:c25:c25:94de:b801
22c19:dd:d9:dd:c25:c25:94de:b802/1272c19:dd:d9:dd:c25:c25:94de:b803
32c19:dd:d9:dd:c25:c25:94de:b804/1272c19:dd:d9:dd:c25:c25:94de:b805
42c19:dd:d9:dd:c25:c25:94de:b806/1272c19:dd:d9:dd:c25:c25:94de:b807
52c19:dd:d9:dd:c25:c25:94de:b808/1272c19:dd:d9:dd:c25:c25:94de:b809
62c19:dd:d9:dd:c25:c25:94de:b80a/1272c19:dd:d9:dd:c25:c25:94de:b80b
72c19:dd:d9:dd:c25:c25:94de:b80c/1272c19:dd:d9:dd:c25:c25:94de:b80d
82c19:dd:d9:dd:c25:c25:94de:b80e/1272c19:dd:d9:dd:c25:c25:94de:b80f
92c19:dd:d9:dd:c25:c25:94de:b810/1272c19:dd:d9:dd:c25:c25:94de:b811
102c19:dd:d9:dd:c25:c25:94de:b812/1272c19:dd:d9:dd:c25:c25:94de:b813
112c19:dd:d9:dd:c25:c25:94de:b814/1272c19:dd:d9:dd:c25:c25:94de:b815
122c19:dd:d9:dd:c25:c25:94de:b816/1272c19:dd:d9:dd:c25:c25:94de:b817
132c19:dd:d9:dd:c25:c25:94de:b818/1272c19:dd:d9:dd:c25:c25:94de:b819
142c19:dd:d9:dd:c25:c25:94de:b81a/1272c19:dd:d9:dd:c25:c25:94de:b81b
152c19:dd:d9:dd:c25:c25:94de:b81c/1272c19:dd:d9:dd:c25:c25:94de:b81d
162c19:dd:d9:dd:c25:c25:94de:b81e/1272c19:dd:d9:dd:c25:c25:94de:b81f
172c19:dd:d9:dd:c25:c25:94de:b820/1272c19:dd:d9:dd:c25:c25:94de:b821
182c19:dd:d9:dd:c25:c25:94de:b822/1272c19:dd:d9:dd:c25:c25:94de:b823
192c19:dd:d9:dd:c25:c25:94de:b824/1272c19:dd:d9:dd:c25:c25:94de:b825
202c19:dd:d9:dd:c25:c25:94de:b826/1272c19:dd:d9:dd:c25:c25:94de:b827
212c19:dd:d9:dd:c25:c25:94de:b828/1272c19:dd:d9:dd:c25:c25:94de:b829
222c19:dd:d9:dd:c25:c25:94de:b82a/1272c19:dd:d9:dd:c25:c25:94de:b82b
232c19:dd:d9:dd:c25:c25:94de:b82c/1272c19:dd:d9:dd:c25:c25:94de:b82d
242c19:dd:d9:dd:c25:c25:94de:b82e/1272c19:dd:d9:dd:c25:c25:94de:b82f
252c19:dd:d9:dd:c25:c25:94de:b830/1272c19:dd:d9:dd:c25:c25:94de:b831
262c19:dd:d9:dd:c25:c25:94de:b832/1272c19:dd:d9:dd:c25:c25:94de:b833
272c19:dd:d9:dd:c25:c25:94de:b834/1272c19:dd:d9:dd:c25:c25:94de:b835
282c19:dd:d9:dd:c25:c25:94de:b836/1272c19:dd:d9:dd:c25:c25:94de:b837
292c19:dd:d9:dd:c25:c25:94de:b838/1272c19:dd:d9:dd:c25:c25:94de:b839
302c19:dd:d9:dd:c25:c25:94de:b83a/1272c19:dd:d9:dd:c25:c25:94de:b83b
312c19:dd:d9:dd:c25:c25:94de:b83c/1272c19:dd:d9:dd:c25:c25:94de:b83d
322c19:dd:d9:dd:c25:c25:94de:b83e/1272c19:dd:d9:dd:c25:c25:94de:b83f
332c19:dd:d9:dd:c25:c25:94de:b840/1272c19:dd:d9:dd:c25:c25:94de:b841
342c19:dd:d9:dd:c25:c25:94de:b842/1272c19:dd:d9:dd:c25:c25:94de:b843
352c19:dd:d9:dd:c25:c25:94de:b844/1272c19:dd:d9:dd:c25:c25:94de:b845
362c19:dd:d9:dd:c25:c25:94de:b846/1272c19:dd:d9:dd:c25:c25:94de:b847
372c19:dd:d9:dd:c25:c25:94de:b848/1272c19:dd:d9:dd:c25:c25:94de:b849
382c19:dd:d9:dd:c25:c25:94de:b84a/1272c19:dd:d9:dd:c25:c25:94de:b84b
392c19:dd:d9:dd:c25:c25:94de:b84c/1272c19:dd:d9:dd:c25:c25:94de:b84d
402c19:dd:d9:dd:c25:c25:94de:b84e/1272c19:dd:d9:dd:c25:c25:94de:b84f
412c19:dd:d9:dd:c25:c25:94de:b850/1272c19:dd:d9:dd:c25:c25:94de:b851
422c19:dd:d9:dd:c25:c25:94de:b852/1272c19:dd:d9:dd:c25:c25:94de:b853
432c19:dd:d9:dd:c25:c25:94de:b854/1272c19:dd:d9:dd:c25:c25:94de:b855
442c19:dd:d9:dd:c25:c25:94de:b856/1272c19:dd:d9:dd:c25:c25:94de:b857
452c19:dd:d9:dd:c25:c25:94de:b858/1272c19:dd:d9:dd:c25:c25:94de:b859
462c19:dd:d9:dd:c25:c25:94de:b85a/1272c19:dd:d9:dd:c25:c25:94de:b85b
472c19:dd:d9:dd:c25:c25:94de:b85c/1272c19:dd:d9:dd:c25:c25:94de:b85d
482c19:dd:d9:dd:c25:c25:94de:b85e/1272c19:dd:d9:dd:c25:c25:94de:b85f
492c19:dd:d9:dd:c25:c25:94de:b860/1272c19:dd:d9:dd:c25:c25:94de:b861
502c19:dd:d9:dd:c25:c25:94de:b862/1272c19:dd:d9:dd:c25:c25:94de:b863
512c19:dd:d9:dd:c25:c25:94de:b864/1272c19:dd:d9:dd:c25:c25:94de:b865
522c19:dd:d9:dd:c25:c25:94de:b866/1272c19:dd:d9:dd:c25:c25:94de:b867
532c19:dd:d9:dd:c25:c25:94de:b868/1272c19:dd:d9:dd:c25:c25:94de:b869
542c19:dd:d9:dd:c25:c25:94de:b86a/1272c19:dd:d9:dd:c25:c25:94de:b86b
552c19:dd:d9:dd:c25:c25:94de:b86c/1272c19:dd:d9:dd:c25:c25:94de:b86d
562c19:dd:d9:dd:c25:c25:94de:b86e/1272c19:dd:d9:dd:c25:c25:94de:b86f
572c19:dd:d9:dd:c25:c25:94de:b870/1272c19:dd:d9:dd:c25:c25:94de:b871
582c19:dd:d9:dd:c25:c25:94de:b872/1272c19:dd:d9:dd:c25:c25:94de:b873
592c19:dd:d9:dd:c25:c25:94de:b874/1272c19:dd:d9:dd:c25:c25:94de:b875
602c19:dd:d9:dd:c25:c25:94de:b876/1272c19:dd:d9:dd:c25:c25:94de:b877
612c19:dd:d9:dd:c25:c25:94de:b878/1272c19:dd:d9:dd:c25:c25:94de:b879
622c19:dd:d9:dd:c25:c25:94de:b87a/1272c19:dd:d9:dd:c25:c25:94de:b87b
632c19:dd:d9:dd:c25:c25:94de:b87c/1272c19:dd:d9:dd:c25:c25:94de:b87d
642c19:dd:d9:dd:c25:c25:94de:b87e/1272c19:dd:d9:dd:c25:c25:94de:b87f
652c19:dd:d9:dd:c25:c25:94de:b880/1272c19:dd:d9:dd:c25:c25:94de:b881
662c19:dd:d9:dd:c25:c25:94de:b882/1272c19:dd:d9:dd:c25:c25:94de:b883
672c19:dd:d9:dd:c25:c25:94de:b884/1272c19:dd:d9:dd:c25:c25:94de:b885
682c19:dd:d9:dd:c25:c25:94de:b886/1272c19:dd:d9:dd:c25:c25:94de:b887
692c19:dd:d9:dd:c25:c25:94de:b888/1272c19:dd:d9:dd:c25:c25:94de:b889
702c19:dd:d9:dd:c25:c25:94de:b88a/1272c19:dd:d9:dd:c25:c25:94de:b88b
712c19:dd:d9:dd:c25:c25:94de:b88c/1272c19:dd:d9:dd:c25:c25:94de:b88d
722c19:dd:d9:dd:c25:c25:94de:b88e/1272c19:dd:d9:dd:c25:c25:94de:b88f
732c19:dd:d9:dd:c25:c25:94de:b890/1272c19:dd:d9:dd:c25:c25:94de:b891
742c19:dd:d9:dd:c25:c25:94de:b892/1272c19:dd:d9:dd:c25:c25:94de:b893
752c19:dd:d9:dd:c25:c25:94de:b894/1272c19:dd:d9:dd:c25:c25:94de:b895
762c19:dd:d9:dd:c25:c25:94de:b896/1272c19:dd:d9:dd:c25:c25:94de:b897
772c19:dd:d9:dd:c25:c25:94de:b898/1272c19:dd:d9:dd:c25:c25:94de:b899
782c19:dd:d9:dd:c25:c25:94de:b89a/1272c19:dd:d9:dd:c25:c25:94de:b89b
792c19:dd:d9:dd:c25:c25:94de:b89c/1272c19:dd:d9:dd:c25:c25:94de:b89d
802c19:dd:d9:dd:c25:c25:94de:b89e/1272c19:dd:d9:dd:c25:c25:94de:b89f
812c19:dd:d9:dd:c25:c25:94de:b8a0/1272c19:dd:d9:dd:c25:c25:94de:b8a1
822c19:dd:d9:dd:c25:c25:94de:b8a2/1272c19:dd:d9:dd:c25:c25:94de:b8a3
832c19:dd:d9:dd:c25:c25:94de:b8a4/1272c19:dd:d9:dd:c25:c25:94de:b8a5
842c19:dd:d9:dd:c25:c25:94de:b8a6/1272c19:dd:d9:dd:c25:c25:94de:b8a7
852c19:dd:d9:dd:c25:c25:94de:b8a8/1272c19:dd:d9:dd:c25:c25:94de:b8a9
862c19:dd:d9:dd:c25:c25:94de:b8aa/1272c19:dd:d9:dd:c25:c25:94de:b8ab
872c19:dd:d9:dd:c25:c25:94de:b8ac/1272c19:dd:d9:dd:c25:c25:94de:b8ad
882c19:dd:d9:dd:c25:c25:94de:b8ae/1272c19:dd:d9:dd:c25:c25:94de:b8af
892c19:dd:d9:dd:c25:c25:94de:b8b0/1272c19:dd:d9:dd:c25:c25:94de:b8b1
902c19:dd:d9:dd:c25:c25:94de:b8b2/1272c19:dd:d9:dd:c25:c25:94de:b8b3
912c19:dd:d9:dd:c25:c25:94de:b8b4/1272c19:dd:d9:dd:c25:c25:94de:b8b5
922c19:dd:d9:dd:c25:c25:94de:b8b6/1272c19:dd:d9:dd:c25:c25:94de:b8b7
932c19:dd:d9:dd:c25:c25:94de:b8b8/1272c19:dd:d9:dd:c25:c25:94de:b8b9
942c19:dd:d9:dd:c25:c25:94de:b8ba/1272c19:dd:d9:dd:c25:c25:94de:b8bb
952c19:dd:d9:dd:c25:c25:94de:b8bc/1272c19:dd:d9:dd:c25:c25:94de:b8bd
962c19:dd:d9:dd:c25:c25:94de:b8be/1272c19:dd:d9:dd:c25:c25:94de:b8bf
972c19:dd:d9:dd:c25:c25:94de:b8c0/1272c19:dd:d9:dd:c25:c25:94de:b8c1
982c19:dd:d9:dd:c25:c25:94de:b8c2/1272c19:dd:d9:dd:c25:c25:94de:b8c3
992c19:dd:d9:dd:c25:c25:94de:b8c4/1272c19:dd:d9:dd:c25:c25:94de:b8c5
1002c19:dd:d9:dd:c25:c25:94de:b8c6/1272c19:dd:d9:dd:c25:c25:94de:b8c7
1012c19:dd:d9:dd:c25:c25:94de:b8c8/1272c19:dd:d9:dd:c25:c25:94de:b8c9
1022c19:dd:d9:dd:c25:c25:94de:b8ca/1272c19:dd:d9:dd:c25:c25:94de:b8cb
1032c19:dd:d9:dd:c25:c25:94de:b8cc/1272c19:dd:d9:dd:c25:c25:94de:b8cd
1042c19:dd:d9:dd:c25:c25:94de:b8ce/1272c19:dd:d9:dd:c25:c25:94de:b8cf
1052c19:dd:d9:dd:c25:c25:94de:b8d0/1272c19:dd:d9:dd:c25:c25:94de:b8d1
1062c19:dd:d9:dd:c25:c25:94de:b8d2/1272c19:dd:d9:dd:c25:c25:94de:b8d3
1072c19:dd:d9:dd:c25:c25:94de:b8d4/1272c19:dd:d9:dd:c25:c25:94de:b8d5
1082c19:dd:d9:dd:c25:c25:94de:b8d6/1272c19:dd:d9:dd:c25:c25:94de:b8d7
1092c19:dd:d9:dd:c25:c25:94de:b8d8/1272c19:dd:d9:dd:c25:c25:94de:b8d9
1102c19:dd:d9:dd:c25:c25:94de:b8da/1272c19:dd:d9:dd:c25:c25:94de:b8db
1112c19:dd:d9:dd:c25:c25:94de:b8dc/1272c19:dd:d9:dd:c25:c25:94de:b8dd
1122c19:dd:d9:dd:c25:c25:94de:b8de/1272c19:dd:d9:dd:c25:c25:94de:b8df
1132c19:dd:d9:dd:c25:c25:94de:b8e0/1272c19:dd:d9:dd:c25:c25:94de:b8e1
1142c19:dd:d9:dd:c25:c25:94de:b8e2/1272c19:dd:d9:dd:c25:c25:94de:b8e3
1152c19:dd:d9:dd:c25:c25:94de:b8e4/1272c19:dd:d9:dd:c25:c25:94de:b8e5
1162c19:dd:d9:dd:c25:c25:94de:b8e6/1272c19:dd:d9:dd:c25:c25:94de:b8e7
1172c19:dd:d9:dd:c25:c25:94de:b8e8/1272c19:dd:d9:dd:c25:c25:94de:b8e9
1182c19:dd:d9:dd:c25:c25:94de:b8ea/1272c19:dd:d9:dd:c25:c25:94de:b8eb
1192c19:dd:d9:dd:c25:c25:94de:b8ec/1272c19:dd:d9:dd:c25:c25:94de:b8ed
1202c19:dd:d9:dd:c25:c25:94de:b8ee/1272c19:dd:d9:dd:c25:c25:94de:b8ef
1212c19:dd:d9:dd:c25:c25:94de:b8f0/1272c19:dd:d9:dd:c25:c25:94de:b8f1
1222c19:dd:d9:dd:c25:c25:94de:b8f2/1272c19:dd:d9:dd:c25:c25:94de:b8f3
1232c19:dd:d9:dd:c25:c25:94de:b8f4/1272c19:dd:d9:dd:c25:c25:94de:b8f5
1242c19:dd:d9:dd:c25:c25:94de:b8f6/1272c19:dd:d9:dd:c25:c25:94de:b8f7
1252c19:dd:d9:dd:c25:c25:94de:b8f8/1272c19:dd:d9:dd:c25:c25:94de:b8f9
1262c19:dd:d9:dd:c25:c25:94de:b8fa/1272c19:dd:d9:dd:c25:c25:94de:b8fb
1272c19:dd:d9:dd:c25:c25:94de:b8fc/1272c19:dd:d9:dd:c25:c25:94de:b8fd
1282c19:dd:d9:dd:c25:c25:94de:b8fe/1272c19:dd:d9:dd:c25:c25:94de:b8ff
1292c19:dd:d9:dd:c25:c25:94de:b900/1272c19:dd:d9:dd:c25:c25:94de:b901
1302c19:dd:d9:dd:c25:c25:94de:b902/1272c19:dd:d9:dd:c25:c25:94de:b903
1312c19:dd:d9:dd:c25:c25:94de:b904/1272c19:dd:d9:dd:c25:c25:94de:b905
1322c19:dd:d9:dd:c25:c25:94de:b906/1272c19:dd:d9:dd:c25:c25:94de:b907
1332c19:dd:d9:dd:c25:c25:94de:b908/1272c19:dd:d9:dd:c25:c25:94de:b909
1342c19:dd:d9:dd:c25:c25:94de:b90a/1272c19:dd:d9:dd:c25:c25:94de:b90b
1352c19:dd:d9:dd:c25:c25:94de:b90c/1272c19:dd:d9:dd:c25:c25:94de:b90d
1362c19:dd:d9:dd:c25:c25:94de:b90e/1272c19:dd:d9:dd:c25:c25:94de:b90f
1372c19:dd:d9:dd:c25:c25:94de:b910/1272c19:dd:d9:dd:c25:c25:94de:b911
1382c19:dd:d9:dd:c25:c25:94de:b912/1272c19:dd:d9:dd:c25:c25:94de:b913
1392c19:dd:d9:dd:c25:c25:94de:b914/1272c19:dd:d9:dd:c25:c25:94de:b915
1402c19:dd:d9:dd:c25:c25:94de:b916/1272c19:dd:d9:dd:c25:c25:94de:b917
1412c19:dd:d9:dd:c25:c25:94de:b918/1272c19:dd:d9:dd:c25:c25:94de:b919
1422c19:dd:d9:dd:c25:c25:94de:b91a/1272c19:dd:d9:dd:c25:c25:94de:b91b
1432c19:dd:d9:dd:c25:c25:94de:b91c/1272c19:dd:d9:dd:c25:c25:94de:b91d
1442c19:dd:d9:dd:c25:c25:94de:b91e/1272c19:dd:d9:dd:c25:c25:94de:b91f
1452c19:dd:d9:dd:c25:c25:94de:b920/1272c19:dd:d9:dd:c25:c25:94de:b921
1462c19:dd:d9:dd:c25:c25:94de:b922/1272c19:dd:d9:dd:c25:c25:94de:b923
1472c19:dd:d9:dd:c25:c25:94de:b924/1272c19:dd:d9:dd:c25:c25:94de:b925
1482c19:dd:d9:dd:c25:c25:94de:b926/1272c19:dd:d9:dd:c25:c25:94de:b927
1492c19:dd:d9:dd:c25:c25:94de:b928/1272c19:dd:d9:dd:c25:c25:94de:b929
1502c19:dd:d9:dd:c25:c25:94de:b92a/1272c19:dd:d9:dd:c25:c25:94de:b92b
1512c19:dd:d9:dd:c25:c25:94de:b92c/1272c19:dd:d9:dd:c25:c25:94de:b92d
1522c19:dd:d9:dd:c25:c25:94de:b92e/1272c19:dd:d9:dd:c25:c25:94de:b92f
1532c19:dd:d9:dd:c25:c25:94de:b930/1272c19:dd:d9:dd:c25:c25:94de:b931
1542c19:dd:d9:dd:c25:c25:94de:b932/1272c19:dd:d9:dd:c25:c25:94de:b933
1552c19:dd:d9:dd:c25:c25:94de:b934/1272c19:dd:d9:dd:c25:c25:94de:b935
1562c19:dd:d9:dd:c25:c25:94de:b936/1272c19:dd:d9:dd:c25:c25:94de:b937
1572c19:dd:d9:dd:c25:c25:94de:b938/1272c19:dd:d9:dd:c25:c25:94de:b939
1582c19:dd:d9:dd:c25:c25:94de:b93a/1272c19:dd:d9:dd:c25:c25:94de:b93b
1592c19:dd:d9:dd:c25:c25:94de:b93c/1272c19:dd:d9:dd:c25:c25:94de:b93d
1602c19:dd:d9:dd:c25:c25:94de:b93e/1272c19:dd:d9:dd:c25:c25:94de:b93f
1612c19:dd:d9:dd:c25:c25:94de:b940/1272c19:dd:d9:dd:c25:c25:94de:b941
1622c19:dd:d9:dd:c25:c25:94de:b942/1272c19:dd:d9:dd:c25:c25:94de:b943
1632c19:dd:d9:dd:c25:c25:94de:b944/1272c19:dd:d9:dd:c25:c25:94de:b945
1642c19:dd:d9:dd:c25:c25:94de:b946/1272c19:dd:d9:dd:c25:c25:94de:b947
1652c19:dd:d9:dd:c25:c25:94de:b948/1272c19:dd:d9:dd:c25:c25:94de:b949
1662c19:dd:d9:dd:c25:c25:94de:b94a/1272c19:dd:d9:dd:c25:c25:94de:b94b
1672c19:dd:d9:dd:c25:c25:94de:b94c/1272c19:dd:d9:dd:c25:c25:94de:b94d
1682c19:dd:d9:dd:c25:c25:94de:b94e/1272c19:dd:d9:dd:c25:c25:94de:b94f
1692c19:dd:d9:dd:c25:c25:94de:b950/1272c19:dd:d9:dd:c25:c25:94de:b951
1702c19:dd:d9:dd:c25:c25:94de:b952/1272c19:dd:d9:dd:c25:c25:94de:b953
1712c19:dd:d9:dd:c25:c25:94de:b954/1272c19:dd:d9:dd:c25:c25:94de:b955
1722c19:dd:d9:dd:c25:c25:94de:b956/1272c19:dd:d9:dd:c25:c25:94de:b957
1732c19:dd:d9:dd:c25:c25:94de:b958/1272c19:dd:d9:dd:c25:c25:94de:b959
1742c19:dd:d9:dd:c25:c25:94de:b95a/1272c19:dd:d9:dd:c25:c25:94de:b95b
1752c19:dd:d9:dd:c25:c25:94de:b95c/1272c19:dd:d9:dd:c25:c25:94de:b95d
1762c19:dd:d9:dd:c25:c25:94de:b95e/1272c19:dd:d9:dd:c25:c25:94de:b95f
1772c19:dd:d9:dd:c25:c25:94de:b960/1272c19:dd:d9:dd:c25:c25:94de:b961
1782c19:dd:d9:dd:c25:c25:94de:b962/1272c19:dd:d9:dd:c25:c25:94de:b963
1792c19:dd:d9:dd:c25:c25:94de:b964/1272c19:dd:d9:dd:c25:c25:94de:b965
1802c19:dd:d9:dd:c25:c25:94de:b966/1272c19:dd:d9:dd:c25:c25:94de:b967
1812c19:dd:d9:dd:c25:c25:94de:b968/1272c19:dd:d9:dd:c25:c25:94de:b969
1822c19:dd:d9:dd:c25:c25:94de:b96a/1272c19:dd:d9:dd:c25:c25:94de:b96b
1832c19:dd:d9:dd:c25:c25:94de:b96c/1272c19:dd:d9:dd:c25:c25:94de:b96d
1842c19:dd:d9:dd:c25:c25:94de:b96e/1272c19:dd:d9:dd:c25:c25:94de:b96f
1852c19:dd:d9:dd:c25:c25:94de:b970/1272c19:dd:d9:dd:c25:c25:94de:b971
1862c19:dd:d9:dd:c25:c25:94de:b972/1272c19:dd:d9:dd:c25:c25:94de:b973
1872c19:dd:d9:dd:c25:c25:94de:b974/1272c19:dd:d9:dd:c25:c25:94de:b975
1882c19:dd:d9:dd:c25:c25:94de:b976/1272c19:dd:d9:dd:c25:c25:94de:b977
1892c19:dd:d9:dd:c25:c25:94de:b978/1272c19:dd:d9:dd:c25:c25:94de:b979
1902c19:dd:d9:dd:c25:c25:94de:b97a/1272c19:dd:d9:dd:c25:c25:94de:b97b
1912c19:dd:d9:dd:c25:c25:94de:b97c/1272c19:dd:d9:dd:c25:c25:94de:b97d
1922c19:dd:d9:dd:c25:c25:94de:b97e/1272c19:dd:d9:dd:c25:c25:94de:b97f
1932c19:dd:d9:dd:c25:c25:94de:b980/1272c19:dd:d9:dd:c25:c25:94de:b981
1942c19:dd:d9:dd:c25:c25:94de:b982/1272c19:dd:d9:dd:c25:c25:94de:b983
1952c19:dd:d9:dd:c25:c25:94de:b984/1272c19:dd:d9:dd:c25:c25:94de:b985
1962c19:dd:d9:dd:c25:c25:94de:b986/1272c19:dd:d9:dd:c25:c25:94de:b987
1972c19:dd:d9:dd:c25:c25:94de:b988/1272c19:dd:d9:dd:c25:c25:94de:b989
1982c19:dd:d9:dd:c25:c25:94de:b98a/1272c19:dd:d9:dd:c25:c25:94de:b98b
1992c19:dd:d9:dd:c25:c25:94de:b98c/1272c19:dd:d9:dd:c25:c25:94de:b98d
2002c19:dd:d9:dd:c25:c25:94de:b98e/1272c19:dd:d9:dd:c25:c25:94de:b98f
2012c19:dd:d9:dd:c25:c25:94de:b990/1272c19:dd:d9:dd:c25:c25:94de:b991
2022c19:dd:d9:dd:c25:c25:94de:b992/1272c19:dd:d9:dd:c25:c25:94de:b993
2032c19:dd:d9:dd:c25:c25:94de:b994/1272c19:dd:d9:dd:c25:c25:94de:b995
2042c19:dd:d9:dd:c25:c25:94de:b996/1272c19:dd:d9:dd:c25:c25:94de:b997
2052c19:dd:d9:dd:c25:c25:94de:b998/1272c19:dd:d9:dd:c25:c25:94de:b999
2062c19:dd:d9:dd:c25:c25:94de:b99a/1272c19:dd:d9:dd:c25:c25:94de:b99b
2072c19:dd:d9:dd:c25:c25:94de:b99c/1272c19:dd:d9:dd:c25:c25:94de:b99d
2082c19:dd:d9:dd:c25:c25:94de:b99e/1272c19:dd:d9:dd:c25:c25:94de:b99f
2092c19:dd:d9:dd:c25:c25:94de:b9a0/1272c19:dd:d9:dd:c25:c25:94de:b9a1
2102c19:dd:d9:dd:c25:c25:94de:b9a2/1272c19:dd:d9:dd:c25:c25:94de:b9a3
2112c19:dd:d9:dd:c25:c25:94de:b9a4/1272c19:dd:d9:dd:c25:c25:94de:b9a5
2122c19:dd:d9:dd:c25:c25:94de:b9a6/1272c19:dd:d9:dd:c25:c25:94de:b9a7
2132c19:dd:d9:dd:c25:c25:94de:b9a8/1272c19:dd:d9:dd:c25:c25:94de:b9a9
2142c19:dd:d9:dd:c25:c25:94de:b9aa/1272c19:dd:d9:dd:c25:c25:94de:b9ab
2152c19:dd:d9:dd:c25:c25:94de:b9ac/1272c19:dd:d9:dd:c25:c25:94de:b9ad
2162c19:dd:d9:dd:c25:c25:94de:b9ae/1272c19:dd:d9:dd:c25:c25:94de:b9af
2172c19:dd:d9:dd:c25:c25:94de:b9b0/1272c19:dd:d9:dd:c25:c25:94de:b9b1
2182c19:dd:d9:dd:c25:c25:94de:b9b2/1272c19:dd:d9:dd:c25:c25:94de:b9b3
2192c19:dd:d9:dd:c25:c25:94de:b9b4/1272c19:dd:d9:dd:c25:c25:94de:b9b5
2202c19:dd:d9:dd:c25:c25:94de:b9b6/1272c19:dd:d9:dd:c25:c25:94de:b9b7
2212c19:dd:d9:dd:c25:c25:94de:b9b8/1272c19:dd:d9:dd:c25:c25:94de:b9b9
2222c19:dd:d9:dd:c25:c25:94de:b9ba/1272c19:dd:d9:dd:c25:c25:94de:b9bb
2232c19:dd:d9:dd:c25:c25:94de:b9bc/1272c19:dd:d9:dd:c25:c25:94de:b9bd
2242c19:dd:d9:dd:c25:c25:94de:b9be/1272c19:dd:d9:dd:c25:c25:94de:b9bf
2252c19:dd:d9:dd:c25:c25:94de:b9c0/1272c19:dd:d9:dd:c25:c25:94de:b9c1
2262c19:dd:d9:dd:c25:c25:94de:b9c2/1272c19:dd:d9:dd:c25:c25:94de:b9c3
2272c19:dd:d9:dd:c25:c25:94de:b9c4/1272c19:dd:d9:dd:c25:c25:94de:b9c5
2282c19:dd:d9:dd:c25:c25:94de:b9c6/1272c19:dd:d9:dd:c25:c25:94de:b9c7
2292c19:dd:d9:dd:c25:c25:94de:b9c8/1272c19:dd:d9:dd:c25:c25:94de:b9c9
2302c19:dd:d9:dd:c25:c25:94de:b9ca/1272c19:dd:d9:dd:c25:c25:94de:b9cb
2312c19:dd:d9:dd:c25:c25:94de:b9cc/1272c19:dd:d9:dd:c25:c25:94de:b9cd
2322c19:dd:d9:dd:c25:c25:94de:b9ce/1272c19:dd:d9:dd:c25:c25:94de:b9cf
2332c19:dd:d9:dd:c25:c25:94de:b9d0/1272c19:dd:d9:dd:c25:c25:94de:b9d1
2342c19:dd:d9:dd:c25:c25:94de:b9d2/1272c19:dd:d9:dd:c25:c25:94de:b9d3
2352c19:dd:d9:dd:c25:c25:94de:b9d4/1272c19:dd:d9:dd:c25:c25:94de:b9d5
2362c19:dd:d9:dd:c25:c25:94de:b9d6/1272c19:dd:d9:dd:c25:c25:94de:b9d7
2372c19:dd:d9:dd:c25:c25:94de:b9d8/1272c19:dd:d9:dd:c25:c25:94de:b9d9
2382c19:dd:d9:dd:c25:c25:94de:b9da/1272c19:dd:d9:dd:c25:c25:94de:b9db
2392c19:dd:d9:dd:c25:c25:94de:b9dc/1272c19:dd:d9:dd:c25:c25:94de:b9dd
2402c19:dd:d9:dd:c25:c25:94de:b9de/1272c19:dd:d9:dd:c25:c25:94de:b9df
2412c19:dd:d9:dd:c25:c25:94de:b9e0/1272c19:dd:d9:dd:c25:c25:94de:b9e1
2422c19:dd:d9:dd:c25:c25:94de:b9e2/1272c19:dd:d9:dd:c25:c25:94de:b9e3
2432c19:dd:d9:dd:c25:c25:94de:b9e4/1272c19:dd:d9:dd:c25:c25:94de:b9e5
2442c19:dd:d9:dd:c25:c25:94de:b9e6/1272c19:dd:d9:dd:c25:c25:94de:b9e7
2452c19:dd:d9:dd:c25:c25:94de:b9e8/1272c19:dd:d9:dd:c25:c25:94de:b9e9
2462c19:dd:d9:dd:c25:c25:94de:b9ea/1272c19:dd:d9:dd:c25:c25:94de:b9eb
2472c19:dd:d9:dd:c25:c25:94de:b9ec/1272c19:dd:d9:dd:c25:c25:94de:b9ed
2482c19:dd:d9:dd:c25:c25:94de:b9ee/1272c19:dd:d9:dd:c25:c25:94de:b9ef
2492c19:dd:d9:dd:c25:c25:94de:b9f0/1272c19:dd:d9:dd:c25:c25:94de:b9f1
2502c19:dd:d9:dd:c25:c25:94de:b9f2/1272c19:dd:d9:dd:c25:c25:94de:b9f3
2512c19:dd:d9:dd:c25:c25:94de:b9f4/1272c19:dd:d9:dd:c25:c25:94de:b9f5
2522c19:dd:d9:dd:c25:c25:94de:b9f6/1272c19:dd:d9:dd:c25:c25:94de:b9f7
2532c19:dd:d9:dd:c25:c25:94de:b9f8/1272c19:dd:d9:dd:c25:c25:94de:b9f9
2542c19:dd:d9:dd:c25:c25:94de:b9fa/1272c19:dd:d9:dd:c25:c25:94de:b9fb
2552c19:dd:d9:dd:c25:c25:94de:b9fc/1272c19:dd:d9:dd:c25:c25:94de:b9fd
2562c19:dd:d9:dd:c25:c25:94de:b9fe/1272c19:dd:d9:dd:c25:c25:94de:b9ff

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.