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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/118
Addresses1,024
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:94de:e800/118
First address
2c19:dd:d9:dd:c25:c25:94de:e800
Last address
2c19:dd:d9:dd:c25:c25:94de:ebff
Addresses
1,024
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:e800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
8.e.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.e.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.e.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.e.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
/118 is not on a 4-bit boundary, so it takes 4 /120 zones.
Split into smaller subnets/127
/119 (2)/120 (4)/121 (8)/122 (16)/124 (64)/127 (512)/128 (1,024)

2c19:dd:d9:dd:c25:c25:94de:e800/118 makes 512 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:e800/1272c19:dd:d9:dd:c25:c25:94de:e801
22c19:dd:d9:dd:c25:c25:94de:e802/1272c19:dd:d9:dd:c25:c25:94de:e803
32c19:dd:d9:dd:c25:c25:94de:e804/1272c19:dd:d9:dd:c25:c25:94de:e805
42c19:dd:d9:dd:c25:c25:94de:e806/1272c19:dd:d9:dd:c25:c25:94de:e807
52c19:dd:d9:dd:c25:c25:94de:e808/1272c19:dd:d9:dd:c25:c25:94de:e809
62c19:dd:d9:dd:c25:c25:94de:e80a/1272c19:dd:d9:dd:c25:c25:94de:e80b
72c19:dd:d9:dd:c25:c25:94de:e80c/1272c19:dd:d9:dd:c25:c25:94de:e80d
82c19:dd:d9:dd:c25:c25:94de:e80e/1272c19:dd:d9:dd:c25:c25:94de:e80f
92c19:dd:d9:dd:c25:c25:94de:e810/1272c19:dd:d9:dd:c25:c25:94de:e811
102c19:dd:d9:dd:c25:c25:94de:e812/1272c19:dd:d9:dd:c25:c25:94de:e813
112c19:dd:d9:dd:c25:c25:94de:e814/1272c19:dd:d9:dd:c25:c25:94de:e815
122c19:dd:d9:dd:c25:c25:94de:e816/1272c19:dd:d9:dd:c25:c25:94de:e817
132c19:dd:d9:dd:c25:c25:94de:e818/1272c19:dd:d9:dd:c25:c25:94de:e819
142c19:dd:d9:dd:c25:c25:94de:e81a/1272c19:dd:d9:dd:c25:c25:94de:e81b
152c19:dd:d9:dd:c25:c25:94de:e81c/1272c19:dd:d9:dd:c25:c25:94de:e81d
162c19:dd:d9:dd:c25:c25:94de:e81e/1272c19:dd:d9:dd:c25:c25:94de:e81f
172c19:dd:d9:dd:c25:c25:94de:e820/1272c19:dd:d9:dd:c25:c25:94de:e821
182c19:dd:d9:dd:c25:c25:94de:e822/1272c19:dd:d9:dd:c25:c25:94de:e823
192c19:dd:d9:dd:c25:c25:94de:e824/1272c19:dd:d9:dd:c25:c25:94de:e825
202c19:dd:d9:dd:c25:c25:94de:e826/1272c19:dd:d9:dd:c25:c25:94de:e827
212c19:dd:d9:dd:c25:c25:94de:e828/1272c19:dd:d9:dd:c25:c25:94de:e829
222c19:dd:d9:dd:c25:c25:94de:e82a/1272c19:dd:d9:dd:c25:c25:94de:e82b
232c19:dd:d9:dd:c25:c25:94de:e82c/1272c19:dd:d9:dd:c25:c25:94de:e82d
242c19:dd:d9:dd:c25:c25:94de:e82e/1272c19:dd:d9:dd:c25:c25:94de:e82f
252c19:dd:d9:dd:c25:c25:94de:e830/1272c19:dd:d9:dd:c25:c25:94de:e831
262c19:dd:d9:dd:c25:c25:94de:e832/1272c19:dd:d9:dd:c25:c25:94de:e833
272c19:dd:d9:dd:c25:c25:94de:e834/1272c19:dd:d9:dd:c25:c25:94de:e835
282c19:dd:d9:dd:c25:c25:94de:e836/1272c19:dd:d9:dd:c25:c25:94de:e837
292c19:dd:d9:dd:c25:c25:94de:e838/1272c19:dd:d9:dd:c25:c25:94de:e839
302c19:dd:d9:dd:c25:c25:94de:e83a/1272c19:dd:d9:dd:c25:c25:94de:e83b
312c19:dd:d9:dd:c25:c25:94de:e83c/1272c19:dd:d9:dd:c25:c25:94de:e83d
322c19:dd:d9:dd:c25:c25:94de:e83e/1272c19:dd:d9:dd:c25:c25:94de:e83f
332c19:dd:d9:dd:c25:c25:94de:e840/1272c19:dd:d9:dd:c25:c25:94de:e841
342c19:dd:d9:dd:c25:c25:94de:e842/1272c19:dd:d9:dd:c25:c25:94de:e843
352c19:dd:d9:dd:c25:c25:94de:e844/1272c19:dd:d9:dd:c25:c25:94de:e845
362c19:dd:d9:dd:c25:c25:94de:e846/1272c19:dd:d9:dd:c25:c25:94de:e847
372c19:dd:d9:dd:c25:c25:94de:e848/1272c19:dd:d9:dd:c25:c25:94de:e849
382c19:dd:d9:dd:c25:c25:94de:e84a/1272c19:dd:d9:dd:c25:c25:94de:e84b
392c19:dd:d9:dd:c25:c25:94de:e84c/1272c19:dd:d9:dd:c25:c25:94de:e84d
402c19:dd:d9:dd:c25:c25:94de:e84e/1272c19:dd:d9:dd:c25:c25:94de:e84f
412c19:dd:d9:dd:c25:c25:94de:e850/1272c19:dd:d9:dd:c25:c25:94de:e851
422c19:dd:d9:dd:c25:c25:94de:e852/1272c19:dd:d9:dd:c25:c25:94de:e853
432c19:dd:d9:dd:c25:c25:94de:e854/1272c19:dd:d9:dd:c25:c25:94de:e855
442c19:dd:d9:dd:c25:c25:94de:e856/1272c19:dd:d9:dd:c25:c25:94de:e857
452c19:dd:d9:dd:c25:c25:94de:e858/1272c19:dd:d9:dd:c25:c25:94de:e859
462c19:dd:d9:dd:c25:c25:94de:e85a/1272c19:dd:d9:dd:c25:c25:94de:e85b
472c19:dd:d9:dd:c25:c25:94de:e85c/1272c19:dd:d9:dd:c25:c25:94de:e85d
482c19:dd:d9:dd:c25:c25:94de:e85e/1272c19:dd:d9:dd:c25:c25:94de:e85f
492c19:dd:d9:dd:c25:c25:94de:e860/1272c19:dd:d9:dd:c25:c25:94de:e861
502c19:dd:d9:dd:c25:c25:94de:e862/1272c19:dd:d9:dd:c25:c25:94de:e863
512c19:dd:d9:dd:c25:c25:94de:e864/1272c19:dd:d9:dd:c25:c25:94de:e865
522c19:dd:d9:dd:c25:c25:94de:e866/1272c19:dd:d9:dd:c25:c25:94de:e867
532c19:dd:d9:dd:c25:c25:94de:e868/1272c19:dd:d9:dd:c25:c25:94de:e869
542c19:dd:d9:dd:c25:c25:94de:e86a/1272c19:dd:d9:dd:c25:c25:94de:e86b
552c19:dd:d9:dd:c25:c25:94de:e86c/1272c19:dd:d9:dd:c25:c25:94de:e86d
562c19:dd:d9:dd:c25:c25:94de:e86e/1272c19:dd:d9:dd:c25:c25:94de:e86f
572c19:dd:d9:dd:c25:c25:94de:e870/1272c19:dd:d9:dd:c25:c25:94de:e871
582c19:dd:d9:dd:c25:c25:94de:e872/1272c19:dd:d9:dd:c25:c25:94de:e873
592c19:dd:d9:dd:c25:c25:94de:e874/1272c19:dd:d9:dd:c25:c25:94de:e875
602c19:dd:d9:dd:c25:c25:94de:e876/1272c19:dd:d9:dd:c25:c25:94de:e877
612c19:dd:d9:dd:c25:c25:94de:e878/1272c19:dd:d9:dd:c25:c25:94de:e879
622c19:dd:d9:dd:c25:c25:94de:e87a/1272c19:dd:d9:dd:c25:c25:94de:e87b
632c19:dd:d9:dd:c25:c25:94de:e87c/1272c19:dd:d9:dd:c25:c25:94de:e87d
642c19:dd:d9:dd:c25:c25:94de:e87e/1272c19:dd:d9:dd:c25:c25:94de:e87f
652c19:dd:d9:dd:c25:c25:94de:e880/1272c19:dd:d9:dd:c25:c25:94de:e881
662c19:dd:d9:dd:c25:c25:94de:e882/1272c19:dd:d9:dd:c25:c25:94de:e883
672c19:dd:d9:dd:c25:c25:94de:e884/1272c19:dd:d9:dd:c25:c25:94de:e885
682c19:dd:d9:dd:c25:c25:94de:e886/1272c19:dd:d9:dd:c25:c25:94de:e887
692c19:dd:d9:dd:c25:c25:94de:e888/1272c19:dd:d9:dd:c25:c25:94de:e889
702c19:dd:d9:dd:c25:c25:94de:e88a/1272c19:dd:d9:dd:c25:c25:94de:e88b
712c19:dd:d9:dd:c25:c25:94de:e88c/1272c19:dd:d9:dd:c25:c25:94de:e88d
722c19:dd:d9:dd:c25:c25:94de:e88e/1272c19:dd:d9:dd:c25:c25:94de:e88f
732c19:dd:d9:dd:c25:c25:94de:e890/1272c19:dd:d9:dd:c25:c25:94de:e891
742c19:dd:d9:dd:c25:c25:94de:e892/1272c19:dd:d9:dd:c25:c25:94de:e893
752c19:dd:d9:dd:c25:c25:94de:e894/1272c19:dd:d9:dd:c25:c25:94de:e895
762c19:dd:d9:dd:c25:c25:94de:e896/1272c19:dd:d9:dd:c25:c25:94de:e897
772c19:dd:d9:dd:c25:c25:94de:e898/1272c19:dd:d9:dd:c25:c25:94de:e899
782c19:dd:d9:dd:c25:c25:94de:e89a/1272c19:dd:d9:dd:c25:c25:94de:e89b
792c19:dd:d9:dd:c25:c25:94de:e89c/1272c19:dd:d9:dd:c25:c25:94de:e89d
802c19:dd:d9:dd:c25:c25:94de:e89e/1272c19:dd:d9:dd:c25:c25:94de:e89f
812c19:dd:d9:dd:c25:c25:94de:e8a0/1272c19:dd:d9:dd:c25:c25:94de:e8a1
822c19:dd:d9:dd:c25:c25:94de:e8a2/1272c19:dd:d9:dd:c25:c25:94de:e8a3
832c19:dd:d9:dd:c25:c25:94de:e8a4/1272c19:dd:d9:dd:c25:c25:94de:e8a5
842c19:dd:d9:dd:c25:c25:94de:e8a6/1272c19:dd:d9:dd:c25:c25:94de:e8a7
852c19:dd:d9:dd:c25:c25:94de:e8a8/1272c19:dd:d9:dd:c25:c25:94de:e8a9
862c19:dd:d9:dd:c25:c25:94de:e8aa/1272c19:dd:d9:dd:c25:c25:94de:e8ab
872c19:dd:d9:dd:c25:c25:94de:e8ac/1272c19:dd:d9:dd:c25:c25:94de:e8ad
882c19:dd:d9:dd:c25:c25:94de:e8ae/1272c19:dd:d9:dd:c25:c25:94de:e8af
892c19:dd:d9:dd:c25:c25:94de:e8b0/1272c19:dd:d9:dd:c25:c25:94de:e8b1
902c19:dd:d9:dd:c25:c25:94de:e8b2/1272c19:dd:d9:dd:c25:c25:94de:e8b3
912c19:dd:d9:dd:c25:c25:94de:e8b4/1272c19:dd:d9:dd:c25:c25:94de:e8b5
922c19:dd:d9:dd:c25:c25:94de:e8b6/1272c19:dd:d9:dd:c25:c25:94de:e8b7
932c19:dd:d9:dd:c25:c25:94de:e8b8/1272c19:dd:d9:dd:c25:c25:94de:e8b9
942c19:dd:d9:dd:c25:c25:94de:e8ba/1272c19:dd:d9:dd:c25:c25:94de:e8bb
952c19:dd:d9:dd:c25:c25:94de:e8bc/1272c19:dd:d9:dd:c25:c25:94de:e8bd
962c19:dd:d9:dd:c25:c25:94de:e8be/1272c19:dd:d9:dd:c25:c25:94de:e8bf
972c19:dd:d9:dd:c25:c25:94de:e8c0/1272c19:dd:d9:dd:c25:c25:94de:e8c1
982c19:dd:d9:dd:c25:c25:94de:e8c2/1272c19:dd:d9:dd:c25:c25:94de:e8c3
992c19:dd:d9:dd:c25:c25:94de:e8c4/1272c19:dd:d9:dd:c25:c25:94de:e8c5
1002c19:dd:d9:dd:c25:c25:94de:e8c6/1272c19:dd:d9:dd:c25:c25:94de:e8c7
1012c19:dd:d9:dd:c25:c25:94de:e8c8/1272c19:dd:d9:dd:c25:c25:94de:e8c9
1022c19:dd:d9:dd:c25:c25:94de:e8ca/1272c19:dd:d9:dd:c25:c25:94de:e8cb
1032c19:dd:d9:dd:c25:c25:94de:e8cc/1272c19:dd:d9:dd:c25:c25:94de:e8cd
1042c19:dd:d9:dd:c25:c25:94de:e8ce/1272c19:dd:d9:dd:c25:c25:94de:e8cf
1052c19:dd:d9:dd:c25:c25:94de:e8d0/1272c19:dd:d9:dd:c25:c25:94de:e8d1
1062c19:dd:d9:dd:c25:c25:94de:e8d2/1272c19:dd:d9:dd:c25:c25:94de:e8d3
1072c19:dd:d9:dd:c25:c25:94de:e8d4/1272c19:dd:d9:dd:c25:c25:94de:e8d5
1082c19:dd:d9:dd:c25:c25:94de:e8d6/1272c19:dd:d9:dd:c25:c25:94de:e8d7
1092c19:dd:d9:dd:c25:c25:94de:e8d8/1272c19:dd:d9:dd:c25:c25:94de:e8d9
1102c19:dd:d9:dd:c25:c25:94de:e8da/1272c19:dd:d9:dd:c25:c25:94de:e8db
1112c19:dd:d9:dd:c25:c25:94de:e8dc/1272c19:dd:d9:dd:c25:c25:94de:e8dd
1122c19:dd:d9:dd:c25:c25:94de:e8de/1272c19:dd:d9:dd:c25:c25:94de:e8df
1132c19:dd:d9:dd:c25:c25:94de:e8e0/1272c19:dd:d9:dd:c25:c25:94de:e8e1
1142c19:dd:d9:dd:c25:c25:94de:e8e2/1272c19:dd:d9:dd:c25:c25:94de:e8e3
1152c19:dd:d9:dd:c25:c25:94de:e8e4/1272c19:dd:d9:dd:c25:c25:94de:e8e5
1162c19:dd:d9:dd:c25:c25:94de:e8e6/1272c19:dd:d9:dd:c25:c25:94de:e8e7
1172c19:dd:d9:dd:c25:c25:94de:e8e8/1272c19:dd:d9:dd:c25:c25:94de:e8e9
1182c19:dd:d9:dd:c25:c25:94de:e8ea/1272c19:dd:d9:dd:c25:c25:94de:e8eb
1192c19:dd:d9:dd:c25:c25:94de:e8ec/1272c19:dd:d9:dd:c25:c25:94de:e8ed
1202c19:dd:d9:dd:c25:c25:94de:e8ee/1272c19:dd:d9:dd:c25:c25:94de:e8ef
1212c19:dd:d9:dd:c25:c25:94de:e8f0/1272c19:dd:d9:dd:c25:c25:94de:e8f1
1222c19:dd:d9:dd:c25:c25:94de:e8f2/1272c19:dd:d9:dd:c25:c25:94de:e8f3
1232c19:dd:d9:dd:c25:c25:94de:e8f4/1272c19:dd:d9:dd:c25:c25:94de:e8f5
1242c19:dd:d9:dd:c25:c25:94de:e8f6/1272c19:dd:d9:dd:c25:c25:94de:e8f7
1252c19:dd:d9:dd:c25:c25:94de:e8f8/1272c19:dd:d9:dd:c25:c25:94de:e8f9
1262c19:dd:d9:dd:c25:c25:94de:e8fa/1272c19:dd:d9:dd:c25:c25:94de:e8fb
1272c19:dd:d9:dd:c25:c25:94de:e8fc/1272c19:dd:d9:dd:c25:c25:94de:e8fd
1282c19:dd:d9:dd:c25:c25:94de:e8fe/1272c19:dd:d9:dd:c25:c25:94de:e8ff
1292c19:dd:d9:dd:c25:c25:94de:e900/1272c19:dd:d9:dd:c25:c25:94de:e901
1302c19:dd:d9:dd:c25:c25:94de:e902/1272c19:dd:d9:dd:c25:c25:94de:e903
1312c19:dd:d9:dd:c25:c25:94de:e904/1272c19:dd:d9:dd:c25:c25:94de:e905
1322c19:dd:d9:dd:c25:c25:94de:e906/1272c19:dd:d9:dd:c25:c25:94de:e907
1332c19:dd:d9:dd:c25:c25:94de:e908/1272c19:dd:d9:dd:c25:c25:94de:e909
1342c19:dd:d9:dd:c25:c25:94de:e90a/1272c19:dd:d9:dd:c25:c25:94de:e90b
1352c19:dd:d9:dd:c25:c25:94de:e90c/1272c19:dd:d9:dd:c25:c25:94de:e90d
1362c19:dd:d9:dd:c25:c25:94de:e90e/1272c19:dd:d9:dd:c25:c25:94de:e90f
1372c19:dd:d9:dd:c25:c25:94de:e910/1272c19:dd:d9:dd:c25:c25:94de:e911
1382c19:dd:d9:dd:c25:c25:94de:e912/1272c19:dd:d9:dd:c25:c25:94de:e913
1392c19:dd:d9:dd:c25:c25:94de:e914/1272c19:dd:d9:dd:c25:c25:94de:e915
1402c19:dd:d9:dd:c25:c25:94de:e916/1272c19:dd:d9:dd:c25:c25:94de:e917
1412c19:dd:d9:dd:c25:c25:94de:e918/1272c19:dd:d9:dd:c25:c25:94de:e919
1422c19:dd:d9:dd:c25:c25:94de:e91a/1272c19:dd:d9:dd:c25:c25:94de:e91b
1432c19:dd:d9:dd:c25:c25:94de:e91c/1272c19:dd:d9:dd:c25:c25:94de:e91d
1442c19:dd:d9:dd:c25:c25:94de:e91e/1272c19:dd:d9:dd:c25:c25:94de:e91f
1452c19:dd:d9:dd:c25:c25:94de:e920/1272c19:dd:d9:dd:c25:c25:94de:e921
1462c19:dd:d9:dd:c25:c25:94de:e922/1272c19:dd:d9:dd:c25:c25:94de:e923
1472c19:dd:d9:dd:c25:c25:94de:e924/1272c19:dd:d9:dd:c25:c25:94de:e925
1482c19:dd:d9:dd:c25:c25:94de:e926/1272c19:dd:d9:dd:c25:c25:94de:e927
1492c19:dd:d9:dd:c25:c25:94de:e928/1272c19:dd:d9:dd:c25:c25:94de:e929
1502c19:dd:d9:dd:c25:c25:94de:e92a/1272c19:dd:d9:dd:c25:c25:94de:e92b
1512c19:dd:d9:dd:c25:c25:94de:e92c/1272c19:dd:d9:dd:c25:c25:94de:e92d
1522c19:dd:d9:dd:c25:c25:94de:e92e/1272c19:dd:d9:dd:c25:c25:94de:e92f
1532c19:dd:d9:dd:c25:c25:94de:e930/1272c19:dd:d9:dd:c25:c25:94de:e931
1542c19:dd:d9:dd:c25:c25:94de:e932/1272c19:dd:d9:dd:c25:c25:94de:e933
1552c19:dd:d9:dd:c25:c25:94de:e934/1272c19:dd:d9:dd:c25:c25:94de:e935
1562c19:dd:d9:dd:c25:c25:94de:e936/1272c19:dd:d9:dd:c25:c25:94de:e937
1572c19:dd:d9:dd:c25:c25:94de:e938/1272c19:dd:d9:dd:c25:c25:94de:e939
1582c19:dd:d9:dd:c25:c25:94de:e93a/1272c19:dd:d9:dd:c25:c25:94de:e93b
1592c19:dd:d9:dd:c25:c25:94de:e93c/1272c19:dd:d9:dd:c25:c25:94de:e93d
1602c19:dd:d9:dd:c25:c25:94de:e93e/1272c19:dd:d9:dd:c25:c25:94de:e93f
1612c19:dd:d9:dd:c25:c25:94de:e940/1272c19:dd:d9:dd:c25:c25:94de:e941
1622c19:dd:d9:dd:c25:c25:94de:e942/1272c19:dd:d9:dd:c25:c25:94de:e943
1632c19:dd:d9:dd:c25:c25:94de:e944/1272c19:dd:d9:dd:c25:c25:94de:e945
1642c19:dd:d9:dd:c25:c25:94de:e946/1272c19:dd:d9:dd:c25:c25:94de:e947
1652c19:dd:d9:dd:c25:c25:94de:e948/1272c19:dd:d9:dd:c25:c25:94de:e949
1662c19:dd:d9:dd:c25:c25:94de:e94a/1272c19:dd:d9:dd:c25:c25:94de:e94b
1672c19:dd:d9:dd:c25:c25:94de:e94c/1272c19:dd:d9:dd:c25:c25:94de:e94d
1682c19:dd:d9:dd:c25:c25:94de:e94e/1272c19:dd:d9:dd:c25:c25:94de:e94f
1692c19:dd:d9:dd:c25:c25:94de:e950/1272c19:dd:d9:dd:c25:c25:94de:e951
1702c19:dd:d9:dd:c25:c25:94de:e952/1272c19:dd:d9:dd:c25:c25:94de:e953
1712c19:dd:d9:dd:c25:c25:94de:e954/1272c19:dd:d9:dd:c25:c25:94de:e955
1722c19:dd:d9:dd:c25:c25:94de:e956/1272c19:dd:d9:dd:c25:c25:94de:e957
1732c19:dd:d9:dd:c25:c25:94de:e958/1272c19:dd:d9:dd:c25:c25:94de:e959
1742c19:dd:d9:dd:c25:c25:94de:e95a/1272c19:dd:d9:dd:c25:c25:94de:e95b
1752c19:dd:d9:dd:c25:c25:94de:e95c/1272c19:dd:d9:dd:c25:c25:94de:e95d
1762c19:dd:d9:dd:c25:c25:94de:e95e/1272c19:dd:d9:dd:c25:c25:94de:e95f
1772c19:dd:d9:dd:c25:c25:94de:e960/1272c19:dd:d9:dd:c25:c25:94de:e961
1782c19:dd:d9:dd:c25:c25:94de:e962/1272c19:dd:d9:dd:c25:c25:94de:e963
1792c19:dd:d9:dd:c25:c25:94de:e964/1272c19:dd:d9:dd:c25:c25:94de:e965
1802c19:dd:d9:dd:c25:c25:94de:e966/1272c19:dd:d9:dd:c25:c25:94de:e967
1812c19:dd:d9:dd:c25:c25:94de:e968/1272c19:dd:d9:dd:c25:c25:94de:e969
1822c19:dd:d9:dd:c25:c25:94de:e96a/1272c19:dd:d9:dd:c25:c25:94de:e96b
1832c19:dd:d9:dd:c25:c25:94de:e96c/1272c19:dd:d9:dd:c25:c25:94de:e96d
1842c19:dd:d9:dd:c25:c25:94de:e96e/1272c19:dd:d9:dd:c25:c25:94de:e96f
1852c19:dd:d9:dd:c25:c25:94de:e970/1272c19:dd:d9:dd:c25:c25:94de:e971
1862c19:dd:d9:dd:c25:c25:94de:e972/1272c19:dd:d9:dd:c25:c25:94de:e973
1872c19:dd:d9:dd:c25:c25:94de:e974/1272c19:dd:d9:dd:c25:c25:94de:e975
1882c19:dd:d9:dd:c25:c25:94de:e976/1272c19:dd:d9:dd:c25:c25:94de:e977
1892c19:dd:d9:dd:c25:c25:94de:e978/1272c19:dd:d9:dd:c25:c25:94de:e979
1902c19:dd:d9:dd:c25:c25:94de:e97a/1272c19:dd:d9:dd:c25:c25:94de:e97b
1912c19:dd:d9:dd:c25:c25:94de:e97c/1272c19:dd:d9:dd:c25:c25:94de:e97d
1922c19:dd:d9:dd:c25:c25:94de:e97e/1272c19:dd:d9:dd:c25:c25:94de:e97f
1932c19:dd:d9:dd:c25:c25:94de:e980/1272c19:dd:d9:dd:c25:c25:94de:e981
1942c19:dd:d9:dd:c25:c25:94de:e982/1272c19:dd:d9:dd:c25:c25:94de:e983
1952c19:dd:d9:dd:c25:c25:94de:e984/1272c19:dd:d9:dd:c25:c25:94de:e985
1962c19:dd:d9:dd:c25:c25:94de:e986/1272c19:dd:d9:dd:c25:c25:94de:e987
1972c19:dd:d9:dd:c25:c25:94de:e988/1272c19:dd:d9:dd:c25:c25:94de:e989
1982c19:dd:d9:dd:c25:c25:94de:e98a/1272c19:dd:d9:dd:c25:c25:94de:e98b
1992c19:dd:d9:dd:c25:c25:94de:e98c/1272c19:dd:d9:dd:c25:c25:94de:e98d
2002c19:dd:d9:dd:c25:c25:94de:e98e/1272c19:dd:d9:dd:c25:c25:94de:e98f
2012c19:dd:d9:dd:c25:c25:94de:e990/1272c19:dd:d9:dd:c25:c25:94de:e991
2022c19:dd:d9:dd:c25:c25:94de:e992/1272c19:dd:d9:dd:c25:c25:94de:e993
2032c19:dd:d9:dd:c25:c25:94de:e994/1272c19:dd:d9:dd:c25:c25:94de:e995
2042c19:dd:d9:dd:c25:c25:94de:e996/1272c19:dd:d9:dd:c25:c25:94de:e997
2052c19:dd:d9:dd:c25:c25:94de:e998/1272c19:dd:d9:dd:c25:c25:94de:e999
2062c19:dd:d9:dd:c25:c25:94de:e99a/1272c19:dd:d9:dd:c25:c25:94de:e99b
2072c19:dd:d9:dd:c25:c25:94de:e99c/1272c19:dd:d9:dd:c25:c25:94de:e99d
2082c19:dd:d9:dd:c25:c25:94de:e99e/1272c19:dd:d9:dd:c25:c25:94de:e99f
2092c19:dd:d9:dd:c25:c25:94de:e9a0/1272c19:dd:d9:dd:c25:c25:94de:e9a1
2102c19:dd:d9:dd:c25:c25:94de:e9a2/1272c19:dd:d9:dd:c25:c25:94de:e9a3
2112c19:dd:d9:dd:c25:c25:94de:e9a4/1272c19:dd:d9:dd:c25:c25:94de:e9a5
2122c19:dd:d9:dd:c25:c25:94de:e9a6/1272c19:dd:d9:dd:c25:c25:94de:e9a7
2132c19:dd:d9:dd:c25:c25:94de:e9a8/1272c19:dd:d9:dd:c25:c25:94de:e9a9
2142c19:dd:d9:dd:c25:c25:94de:e9aa/1272c19:dd:d9:dd:c25:c25:94de:e9ab
2152c19:dd:d9:dd:c25:c25:94de:e9ac/1272c19:dd:d9:dd:c25:c25:94de:e9ad
2162c19:dd:d9:dd:c25:c25:94de:e9ae/1272c19:dd:d9:dd:c25:c25:94de:e9af
2172c19:dd:d9:dd:c25:c25:94de:e9b0/1272c19:dd:d9:dd:c25:c25:94de:e9b1
2182c19:dd:d9:dd:c25:c25:94de:e9b2/1272c19:dd:d9:dd:c25:c25:94de:e9b3
2192c19:dd:d9:dd:c25:c25:94de:e9b4/1272c19:dd:d9:dd:c25:c25:94de:e9b5
2202c19:dd:d9:dd:c25:c25:94de:e9b6/1272c19:dd:d9:dd:c25:c25:94de:e9b7
2212c19:dd:d9:dd:c25:c25:94de:e9b8/1272c19:dd:d9:dd:c25:c25:94de:e9b9
2222c19:dd:d9:dd:c25:c25:94de:e9ba/1272c19:dd:d9:dd:c25:c25:94de:e9bb
2232c19:dd:d9:dd:c25:c25:94de:e9bc/1272c19:dd:d9:dd:c25:c25:94de:e9bd
2242c19:dd:d9:dd:c25:c25:94de:e9be/1272c19:dd:d9:dd:c25:c25:94de:e9bf
2252c19:dd:d9:dd:c25:c25:94de:e9c0/1272c19:dd:d9:dd:c25:c25:94de:e9c1
2262c19:dd:d9:dd:c25:c25:94de:e9c2/1272c19:dd:d9:dd:c25:c25:94de:e9c3
2272c19:dd:d9:dd:c25:c25:94de:e9c4/1272c19:dd:d9:dd:c25:c25:94de:e9c5
2282c19:dd:d9:dd:c25:c25:94de:e9c6/1272c19:dd:d9:dd:c25:c25:94de:e9c7
2292c19:dd:d9:dd:c25:c25:94de:e9c8/1272c19:dd:d9:dd:c25:c25:94de:e9c9
2302c19:dd:d9:dd:c25:c25:94de:e9ca/1272c19:dd:d9:dd:c25:c25:94de:e9cb
2312c19:dd:d9:dd:c25:c25:94de:e9cc/1272c19:dd:d9:dd:c25:c25:94de:e9cd
2322c19:dd:d9:dd:c25:c25:94de:e9ce/1272c19:dd:d9:dd:c25:c25:94de:e9cf
2332c19:dd:d9:dd:c25:c25:94de:e9d0/1272c19:dd:d9:dd:c25:c25:94de:e9d1
2342c19:dd:d9:dd:c25:c25:94de:e9d2/1272c19:dd:d9:dd:c25:c25:94de:e9d3
2352c19:dd:d9:dd:c25:c25:94de:e9d4/1272c19:dd:d9:dd:c25:c25:94de:e9d5
2362c19:dd:d9:dd:c25:c25:94de:e9d6/1272c19:dd:d9:dd:c25:c25:94de:e9d7
2372c19:dd:d9:dd:c25:c25:94de:e9d8/1272c19:dd:d9:dd:c25:c25:94de:e9d9
2382c19:dd:d9:dd:c25:c25:94de:e9da/1272c19:dd:d9:dd:c25:c25:94de:e9db
2392c19:dd:d9:dd:c25:c25:94de:e9dc/1272c19:dd:d9:dd:c25:c25:94de:e9dd
2402c19:dd:d9:dd:c25:c25:94de:e9de/1272c19:dd:d9:dd:c25:c25:94de:e9df
2412c19:dd:d9:dd:c25:c25:94de:e9e0/1272c19:dd:d9:dd:c25:c25:94de:e9e1
2422c19:dd:d9:dd:c25:c25:94de:e9e2/1272c19:dd:d9:dd:c25:c25:94de:e9e3
2432c19:dd:d9:dd:c25:c25:94de:e9e4/1272c19:dd:d9:dd:c25:c25:94de:e9e5
2442c19:dd:d9:dd:c25:c25:94de:e9e6/1272c19:dd:d9:dd:c25:c25:94de:e9e7
2452c19:dd:d9:dd:c25:c25:94de:e9e8/1272c19:dd:d9:dd:c25:c25:94de:e9e9
2462c19:dd:d9:dd:c25:c25:94de:e9ea/1272c19:dd:d9:dd:c25:c25:94de:e9eb
2472c19:dd:d9:dd:c25:c25:94de:e9ec/1272c19:dd:d9:dd:c25:c25:94de:e9ed
2482c19:dd:d9:dd:c25:c25:94de:e9ee/1272c19:dd:d9:dd:c25:c25:94de:e9ef
2492c19:dd:d9:dd:c25:c25:94de:e9f0/1272c19:dd:d9:dd:c25:c25:94de:e9f1
2502c19:dd:d9:dd:c25:c25:94de:e9f2/1272c19:dd:d9:dd:c25:c25:94de:e9f3
2512c19:dd:d9:dd:c25:c25:94de:e9f4/1272c19:dd:d9:dd:c25:c25:94de:e9f5
2522c19:dd:d9:dd:c25:c25:94de:e9f6/1272c19:dd:d9:dd:c25:c25:94de:e9f7
2532c19:dd:d9:dd:c25:c25:94de:e9f8/1272c19:dd:d9:dd:c25:c25:94de:e9f9
2542c19:dd:d9:dd:c25:c25:94de:e9fa/1272c19:dd:d9:dd:c25:c25:94de:e9fb
2552c19:dd:d9:dd:c25:c25:94de:e9fc/1272c19:dd:d9:dd:c25:c25:94de:e9fd
2562c19:dd:d9:dd:c25:c25:94de:e9fe/1272c19:dd:d9:dd:c25:c25:94de:e9ff

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.