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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/120
Addresses256
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25b:d00a:c700/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:c700
Last address
2c19:dd:d9:dd:c25:c25b:d00a:c7ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:c700
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
7.c.a.0.0.d.b.5.2.c.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25b:d00a:c700/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:c700/1282c19:dd:d9:dd:c25:c25b:d00a:c700
22c19:dd:d9:dd:c25:c25b:d00a:c701/1282c19:dd:d9:dd:c25:c25b:d00a:c701
32c19:dd:d9:dd:c25:c25b:d00a:c702/1282c19:dd:d9:dd:c25:c25b:d00a:c702
42c19:dd:d9:dd:c25:c25b:d00a:c703/1282c19:dd:d9:dd:c25:c25b:d00a:c703
52c19:dd:d9:dd:c25:c25b:d00a:c704/1282c19:dd:d9:dd:c25:c25b:d00a:c704
62c19:dd:d9:dd:c25:c25b:d00a:c705/1282c19:dd:d9:dd:c25:c25b:d00a:c705
72c19:dd:d9:dd:c25:c25b:d00a:c706/1282c19:dd:d9:dd:c25:c25b:d00a:c706
82c19:dd:d9:dd:c25:c25b:d00a:c707/1282c19:dd:d9:dd:c25:c25b:d00a:c707
92c19:dd:d9:dd:c25:c25b:d00a:c708/1282c19:dd:d9:dd:c25:c25b:d00a:c708
102c19:dd:d9:dd:c25:c25b:d00a:c709/1282c19:dd:d9:dd:c25:c25b:d00a:c709
112c19:dd:d9:dd:c25:c25b:d00a:c70a/1282c19:dd:d9:dd:c25:c25b:d00a:c70a
122c19:dd:d9:dd:c25:c25b:d00a:c70b/1282c19:dd:d9:dd:c25:c25b:d00a:c70b
132c19:dd:d9:dd:c25:c25b:d00a:c70c/1282c19:dd:d9:dd:c25:c25b:d00a:c70c
142c19:dd:d9:dd:c25:c25b:d00a:c70d/1282c19:dd:d9:dd:c25:c25b:d00a:c70d
152c19:dd:d9:dd:c25:c25b:d00a:c70e/1282c19:dd:d9:dd:c25:c25b:d00a:c70e
162c19:dd:d9:dd:c25:c25b:d00a:c70f/1282c19:dd:d9:dd:c25:c25b:d00a:c70f
172c19:dd:d9:dd:c25:c25b:d00a:c710/1282c19:dd:d9:dd:c25:c25b:d00a:c710
182c19:dd:d9:dd:c25:c25b:d00a:c711/1282c19:dd:d9:dd:c25:c25b:d00a:c711
192c19:dd:d9:dd:c25:c25b:d00a:c712/1282c19:dd:d9:dd:c25:c25b:d00a:c712
202c19:dd:d9:dd:c25:c25b:d00a:c713/1282c19:dd:d9:dd:c25:c25b:d00a:c713
212c19:dd:d9:dd:c25:c25b:d00a:c714/1282c19:dd:d9:dd:c25:c25b:d00a:c714
222c19:dd:d9:dd:c25:c25b:d00a:c715/1282c19:dd:d9:dd:c25:c25b:d00a:c715
232c19:dd:d9:dd:c25:c25b:d00a:c716/1282c19:dd:d9:dd:c25:c25b:d00a:c716
242c19:dd:d9:dd:c25:c25b:d00a:c717/1282c19:dd:d9:dd:c25:c25b:d00a:c717
252c19:dd:d9:dd:c25:c25b:d00a:c718/1282c19:dd:d9:dd:c25:c25b:d00a:c718
262c19:dd:d9:dd:c25:c25b:d00a:c719/1282c19:dd:d9:dd:c25:c25b:d00a:c719
272c19:dd:d9:dd:c25:c25b:d00a:c71a/1282c19:dd:d9:dd:c25:c25b:d00a:c71a
282c19:dd:d9:dd:c25:c25b:d00a:c71b/1282c19:dd:d9:dd:c25:c25b:d00a:c71b
292c19:dd:d9:dd:c25:c25b:d00a:c71c/1282c19:dd:d9:dd:c25:c25b:d00a:c71c
302c19:dd:d9:dd:c25:c25b:d00a:c71d/1282c19:dd:d9:dd:c25:c25b:d00a:c71d
312c19:dd:d9:dd:c25:c25b:d00a:c71e/1282c19:dd:d9:dd:c25:c25b:d00a:c71e
322c19:dd:d9:dd:c25:c25b:d00a:c71f/1282c19:dd:d9:dd:c25:c25b:d00a:c71f
332c19:dd:d9:dd:c25:c25b:d00a:c720/1282c19:dd:d9:dd:c25:c25b:d00a:c720
342c19:dd:d9:dd:c25:c25b:d00a:c721/1282c19:dd:d9:dd:c25:c25b:d00a:c721
352c19:dd:d9:dd:c25:c25b:d00a:c722/1282c19:dd:d9:dd:c25:c25b:d00a:c722
362c19:dd:d9:dd:c25:c25b:d00a:c723/1282c19:dd:d9:dd:c25:c25b:d00a:c723
372c19:dd:d9:dd:c25:c25b:d00a:c724/1282c19:dd:d9:dd:c25:c25b:d00a:c724
382c19:dd:d9:dd:c25:c25b:d00a:c725/1282c19:dd:d9:dd:c25:c25b:d00a:c725
392c19:dd:d9:dd:c25:c25b:d00a:c726/1282c19:dd:d9:dd:c25:c25b:d00a:c726
402c19:dd:d9:dd:c25:c25b:d00a:c727/1282c19:dd:d9:dd:c25:c25b:d00a:c727
412c19:dd:d9:dd:c25:c25b:d00a:c728/1282c19:dd:d9:dd:c25:c25b:d00a:c728
422c19:dd:d9:dd:c25:c25b:d00a:c729/1282c19:dd:d9:dd:c25:c25b:d00a:c729
432c19:dd:d9:dd:c25:c25b:d00a:c72a/1282c19:dd:d9:dd:c25:c25b:d00a:c72a
442c19:dd:d9:dd:c25:c25b:d00a:c72b/1282c19:dd:d9:dd:c25:c25b:d00a:c72b
452c19:dd:d9:dd:c25:c25b:d00a:c72c/1282c19:dd:d9:dd:c25:c25b:d00a:c72c
462c19:dd:d9:dd:c25:c25b:d00a:c72d/1282c19:dd:d9:dd:c25:c25b:d00a:c72d
472c19:dd:d9:dd:c25:c25b:d00a:c72e/1282c19:dd:d9:dd:c25:c25b:d00a:c72e
482c19:dd:d9:dd:c25:c25b:d00a:c72f/1282c19:dd:d9:dd:c25:c25b:d00a:c72f
492c19:dd:d9:dd:c25:c25b:d00a:c730/1282c19:dd:d9:dd:c25:c25b:d00a:c730
502c19:dd:d9:dd:c25:c25b:d00a:c731/1282c19:dd:d9:dd:c25:c25b:d00a:c731
512c19:dd:d9:dd:c25:c25b:d00a:c732/1282c19:dd:d9:dd:c25:c25b:d00a:c732
522c19:dd:d9:dd:c25:c25b:d00a:c733/1282c19:dd:d9:dd:c25:c25b:d00a:c733
532c19:dd:d9:dd:c25:c25b:d00a:c734/1282c19:dd:d9:dd:c25:c25b:d00a:c734
542c19:dd:d9:dd:c25:c25b:d00a:c735/1282c19:dd:d9:dd:c25:c25b:d00a:c735
552c19:dd:d9:dd:c25:c25b:d00a:c736/1282c19:dd:d9:dd:c25:c25b:d00a:c736
562c19:dd:d9:dd:c25:c25b:d00a:c737/1282c19:dd:d9:dd:c25:c25b:d00a:c737
572c19:dd:d9:dd:c25:c25b:d00a:c738/1282c19:dd:d9:dd:c25:c25b:d00a:c738
582c19:dd:d9:dd:c25:c25b:d00a:c739/1282c19:dd:d9:dd:c25:c25b:d00a:c739
592c19:dd:d9:dd:c25:c25b:d00a:c73a/1282c19:dd:d9:dd:c25:c25b:d00a:c73a
602c19:dd:d9:dd:c25:c25b:d00a:c73b/1282c19:dd:d9:dd:c25:c25b:d00a:c73b
612c19:dd:d9:dd:c25:c25b:d00a:c73c/1282c19:dd:d9:dd:c25:c25b:d00a:c73c
622c19:dd:d9:dd:c25:c25b:d00a:c73d/1282c19:dd:d9:dd:c25:c25b:d00a:c73d
632c19:dd:d9:dd:c25:c25b:d00a:c73e/1282c19:dd:d9:dd:c25:c25b:d00a:c73e
642c19:dd:d9:dd:c25:c25b:d00a:c73f/1282c19:dd:d9:dd:c25:c25b:d00a:c73f
652c19:dd:d9:dd:c25:c25b:d00a:c740/1282c19:dd:d9:dd:c25:c25b:d00a:c740
662c19:dd:d9:dd:c25:c25b:d00a:c741/1282c19:dd:d9:dd:c25:c25b:d00a:c741
672c19:dd:d9:dd:c25:c25b:d00a:c742/1282c19:dd:d9:dd:c25:c25b:d00a:c742
682c19:dd:d9:dd:c25:c25b:d00a:c743/1282c19:dd:d9:dd:c25:c25b:d00a:c743
692c19:dd:d9:dd:c25:c25b:d00a:c744/1282c19:dd:d9:dd:c25:c25b:d00a:c744
702c19:dd:d9:dd:c25:c25b:d00a:c745/1282c19:dd:d9:dd:c25:c25b:d00a:c745
712c19:dd:d9:dd:c25:c25b:d00a:c746/1282c19:dd:d9:dd:c25:c25b:d00a:c746
722c19:dd:d9:dd:c25:c25b:d00a:c747/1282c19:dd:d9:dd:c25:c25b:d00a:c747
732c19:dd:d9:dd:c25:c25b:d00a:c748/1282c19:dd:d9:dd:c25:c25b:d00a:c748
742c19:dd:d9:dd:c25:c25b:d00a:c749/1282c19:dd:d9:dd:c25:c25b:d00a:c749
752c19:dd:d9:dd:c25:c25b:d00a:c74a/1282c19:dd:d9:dd:c25:c25b:d00a:c74a
762c19:dd:d9:dd:c25:c25b:d00a:c74b/1282c19:dd:d9:dd:c25:c25b:d00a:c74b
772c19:dd:d9:dd:c25:c25b:d00a:c74c/1282c19:dd:d9:dd:c25:c25b:d00a:c74c
782c19:dd:d9:dd:c25:c25b:d00a:c74d/1282c19:dd:d9:dd:c25:c25b:d00a:c74d
792c19:dd:d9:dd:c25:c25b:d00a:c74e/1282c19:dd:d9:dd:c25:c25b:d00a:c74e
802c19:dd:d9:dd:c25:c25b:d00a:c74f/1282c19:dd:d9:dd:c25:c25b:d00a:c74f
812c19:dd:d9:dd:c25:c25b:d00a:c750/1282c19:dd:d9:dd:c25:c25b:d00a:c750
822c19:dd:d9:dd:c25:c25b:d00a:c751/1282c19:dd:d9:dd:c25:c25b:d00a:c751
832c19:dd:d9:dd:c25:c25b:d00a:c752/1282c19:dd:d9:dd:c25:c25b:d00a:c752
842c19:dd:d9:dd:c25:c25b:d00a:c753/1282c19:dd:d9:dd:c25:c25b:d00a:c753
852c19:dd:d9:dd:c25:c25b:d00a:c754/1282c19:dd:d9:dd:c25:c25b:d00a:c754
862c19:dd:d9:dd:c25:c25b:d00a:c755/1282c19:dd:d9:dd:c25:c25b:d00a:c755
872c19:dd:d9:dd:c25:c25b:d00a:c756/1282c19:dd:d9:dd:c25:c25b:d00a:c756
882c19:dd:d9:dd:c25:c25b:d00a:c757/1282c19:dd:d9:dd:c25:c25b:d00a:c757
892c19:dd:d9:dd:c25:c25b:d00a:c758/1282c19:dd:d9:dd:c25:c25b:d00a:c758
902c19:dd:d9:dd:c25:c25b:d00a:c759/1282c19:dd:d9:dd:c25:c25b:d00a:c759
912c19:dd:d9:dd:c25:c25b:d00a:c75a/1282c19:dd:d9:dd:c25:c25b:d00a:c75a
922c19:dd:d9:dd:c25:c25b:d00a:c75b/1282c19:dd:d9:dd:c25:c25b:d00a:c75b
932c19:dd:d9:dd:c25:c25b:d00a:c75c/1282c19:dd:d9:dd:c25:c25b:d00a:c75c
942c19:dd:d9:dd:c25:c25b:d00a:c75d/1282c19:dd:d9:dd:c25:c25b:d00a:c75d
952c19:dd:d9:dd:c25:c25b:d00a:c75e/1282c19:dd:d9:dd:c25:c25b:d00a:c75e
962c19:dd:d9:dd:c25:c25b:d00a:c75f/1282c19:dd:d9:dd:c25:c25b:d00a:c75f
972c19:dd:d9:dd:c25:c25b:d00a:c760/1282c19:dd:d9:dd:c25:c25b:d00a:c760
982c19:dd:d9:dd:c25:c25b:d00a:c761/1282c19:dd:d9:dd:c25:c25b:d00a:c761
992c19:dd:d9:dd:c25:c25b:d00a:c762/1282c19:dd:d9:dd:c25:c25b:d00a:c762
1002c19:dd:d9:dd:c25:c25b:d00a:c763/1282c19:dd:d9:dd:c25:c25b:d00a:c763
1012c19:dd:d9:dd:c25:c25b:d00a:c764/1282c19:dd:d9:dd:c25:c25b:d00a:c764
1022c19:dd:d9:dd:c25:c25b:d00a:c765/1282c19:dd:d9:dd:c25:c25b:d00a:c765
1032c19:dd:d9:dd:c25:c25b:d00a:c766/1282c19:dd:d9:dd:c25:c25b:d00a:c766
1042c19:dd:d9:dd:c25:c25b:d00a:c767/1282c19:dd:d9:dd:c25:c25b:d00a:c767
1052c19:dd:d9:dd:c25:c25b:d00a:c768/1282c19:dd:d9:dd:c25:c25b:d00a:c768
1062c19:dd:d9:dd:c25:c25b:d00a:c769/1282c19:dd:d9:dd:c25:c25b:d00a:c769
1072c19:dd:d9:dd:c25:c25b:d00a:c76a/1282c19:dd:d9:dd:c25:c25b:d00a:c76a
1082c19:dd:d9:dd:c25:c25b:d00a:c76b/1282c19:dd:d9:dd:c25:c25b:d00a:c76b
1092c19:dd:d9:dd:c25:c25b:d00a:c76c/1282c19:dd:d9:dd:c25:c25b:d00a:c76c
1102c19:dd:d9:dd:c25:c25b:d00a:c76d/1282c19:dd:d9:dd:c25:c25b:d00a:c76d
1112c19:dd:d9:dd:c25:c25b:d00a:c76e/1282c19:dd:d9:dd:c25:c25b:d00a:c76e
1122c19:dd:d9:dd:c25:c25b:d00a:c76f/1282c19:dd:d9:dd:c25:c25b:d00a:c76f
1132c19:dd:d9:dd:c25:c25b:d00a:c770/1282c19:dd:d9:dd:c25:c25b:d00a:c770
1142c19:dd:d9:dd:c25:c25b:d00a:c771/1282c19:dd:d9:dd:c25:c25b:d00a:c771
1152c19:dd:d9:dd:c25:c25b:d00a:c772/1282c19:dd:d9:dd:c25:c25b:d00a:c772
1162c19:dd:d9:dd:c25:c25b:d00a:c773/1282c19:dd:d9:dd:c25:c25b:d00a:c773
1172c19:dd:d9:dd:c25:c25b:d00a:c774/1282c19:dd:d9:dd:c25:c25b:d00a:c774
1182c19:dd:d9:dd:c25:c25b:d00a:c775/1282c19:dd:d9:dd:c25:c25b:d00a:c775
1192c19:dd:d9:dd:c25:c25b:d00a:c776/1282c19:dd:d9:dd:c25:c25b:d00a:c776
1202c19:dd:d9:dd:c25:c25b:d00a:c777/1282c19:dd:d9:dd:c25:c25b:d00a:c777
1212c19:dd:d9:dd:c25:c25b:d00a:c778/1282c19:dd:d9:dd:c25:c25b:d00a:c778
1222c19:dd:d9:dd:c25:c25b:d00a:c779/1282c19:dd:d9:dd:c25:c25b:d00a:c779
1232c19:dd:d9:dd:c25:c25b:d00a:c77a/1282c19:dd:d9:dd:c25:c25b:d00a:c77a
1242c19:dd:d9:dd:c25:c25b:d00a:c77b/1282c19:dd:d9:dd:c25:c25b:d00a:c77b
1252c19:dd:d9:dd:c25:c25b:d00a:c77c/1282c19:dd:d9:dd:c25:c25b:d00a:c77c
1262c19:dd:d9:dd:c25:c25b:d00a:c77d/1282c19:dd:d9:dd:c25:c25b:d00a:c77d
1272c19:dd:d9:dd:c25:c25b:d00a:c77e/1282c19:dd:d9:dd:c25:c25b:d00a:c77e
1282c19:dd:d9:dd:c25:c25b:d00a:c77f/1282c19:dd:d9:dd:c25:c25b:d00a:c77f
1292c19:dd:d9:dd:c25:c25b:d00a:c780/1282c19:dd:d9:dd:c25:c25b:d00a:c780
1302c19:dd:d9:dd:c25:c25b:d00a:c781/1282c19:dd:d9:dd:c25:c25b:d00a:c781
1312c19:dd:d9:dd:c25:c25b:d00a:c782/1282c19:dd:d9:dd:c25:c25b:d00a:c782
1322c19:dd:d9:dd:c25:c25b:d00a:c783/1282c19:dd:d9:dd:c25:c25b:d00a:c783
1332c19:dd:d9:dd:c25:c25b:d00a:c784/1282c19:dd:d9:dd:c25:c25b:d00a:c784
1342c19:dd:d9:dd:c25:c25b:d00a:c785/1282c19:dd:d9:dd:c25:c25b:d00a:c785
1352c19:dd:d9:dd:c25:c25b:d00a:c786/1282c19:dd:d9:dd:c25:c25b:d00a:c786
1362c19:dd:d9:dd:c25:c25b:d00a:c787/1282c19:dd:d9:dd:c25:c25b:d00a:c787
1372c19:dd:d9:dd:c25:c25b:d00a:c788/1282c19:dd:d9:dd:c25:c25b:d00a:c788
1382c19:dd:d9:dd:c25:c25b:d00a:c789/1282c19:dd:d9:dd:c25:c25b:d00a:c789
1392c19:dd:d9:dd:c25:c25b:d00a:c78a/1282c19:dd:d9:dd:c25:c25b:d00a:c78a
1402c19:dd:d9:dd:c25:c25b:d00a:c78b/1282c19:dd:d9:dd:c25:c25b:d00a:c78b
1412c19:dd:d9:dd:c25:c25b:d00a:c78c/1282c19:dd:d9:dd:c25:c25b:d00a:c78c
1422c19:dd:d9:dd:c25:c25b:d00a:c78d/1282c19:dd:d9:dd:c25:c25b:d00a:c78d
1432c19:dd:d9:dd:c25:c25b:d00a:c78e/1282c19:dd:d9:dd:c25:c25b:d00a:c78e
1442c19:dd:d9:dd:c25:c25b:d00a:c78f/1282c19:dd:d9:dd:c25:c25b:d00a:c78f
1452c19:dd:d9:dd:c25:c25b:d00a:c790/1282c19:dd:d9:dd:c25:c25b:d00a:c790
1462c19:dd:d9:dd:c25:c25b:d00a:c791/1282c19:dd:d9:dd:c25:c25b:d00a:c791
1472c19:dd:d9:dd:c25:c25b:d00a:c792/1282c19:dd:d9:dd:c25:c25b:d00a:c792
1482c19:dd:d9:dd:c25:c25b:d00a:c793/1282c19:dd:d9:dd:c25:c25b:d00a:c793
1492c19:dd:d9:dd:c25:c25b:d00a:c794/1282c19:dd:d9:dd:c25:c25b:d00a:c794
1502c19:dd:d9:dd:c25:c25b:d00a:c795/1282c19:dd:d9:dd:c25:c25b:d00a:c795
1512c19:dd:d9:dd:c25:c25b:d00a:c796/1282c19:dd:d9:dd:c25:c25b:d00a:c796
1522c19:dd:d9:dd:c25:c25b:d00a:c797/1282c19:dd:d9:dd:c25:c25b:d00a:c797
1532c19:dd:d9:dd:c25:c25b:d00a:c798/1282c19:dd:d9:dd:c25:c25b:d00a:c798
1542c19:dd:d9:dd:c25:c25b:d00a:c799/1282c19:dd:d9:dd:c25:c25b:d00a:c799
1552c19:dd:d9:dd:c25:c25b:d00a:c79a/1282c19:dd:d9:dd:c25:c25b:d00a:c79a
1562c19:dd:d9:dd:c25:c25b:d00a:c79b/1282c19:dd:d9:dd:c25:c25b:d00a:c79b
1572c19:dd:d9:dd:c25:c25b:d00a:c79c/1282c19:dd:d9:dd:c25:c25b:d00a:c79c
1582c19:dd:d9:dd:c25:c25b:d00a:c79d/1282c19:dd:d9:dd:c25:c25b:d00a:c79d
1592c19:dd:d9:dd:c25:c25b:d00a:c79e/1282c19:dd:d9:dd:c25:c25b:d00a:c79e
1602c19:dd:d9:dd:c25:c25b:d00a:c79f/1282c19:dd:d9:dd:c25:c25b:d00a:c79f
1612c19:dd:d9:dd:c25:c25b:d00a:c7a0/1282c19:dd:d9:dd:c25:c25b:d00a:c7a0
1622c19:dd:d9:dd:c25:c25b:d00a:c7a1/1282c19:dd:d9:dd:c25:c25b:d00a:c7a1
1632c19:dd:d9:dd:c25:c25b:d00a:c7a2/1282c19:dd:d9:dd:c25:c25b:d00a:c7a2
1642c19:dd:d9:dd:c25:c25b:d00a:c7a3/1282c19:dd:d9:dd:c25:c25b:d00a:c7a3
1652c19:dd:d9:dd:c25:c25b:d00a:c7a4/1282c19:dd:d9:dd:c25:c25b:d00a:c7a4
1662c19:dd:d9:dd:c25:c25b:d00a:c7a5/1282c19:dd:d9:dd:c25:c25b:d00a:c7a5
1672c19:dd:d9:dd:c25:c25b:d00a:c7a6/1282c19:dd:d9:dd:c25:c25b:d00a:c7a6
1682c19:dd:d9:dd:c25:c25b:d00a:c7a7/1282c19:dd:d9:dd:c25:c25b:d00a:c7a7
1692c19:dd:d9:dd:c25:c25b:d00a:c7a8/1282c19:dd:d9:dd:c25:c25b:d00a:c7a8
1702c19:dd:d9:dd:c25:c25b:d00a:c7a9/1282c19:dd:d9:dd:c25:c25b:d00a:c7a9
1712c19:dd:d9:dd:c25:c25b:d00a:c7aa/1282c19:dd:d9:dd:c25:c25b:d00a:c7aa
1722c19:dd:d9:dd:c25:c25b:d00a:c7ab/1282c19:dd:d9:dd:c25:c25b:d00a:c7ab
1732c19:dd:d9:dd:c25:c25b:d00a:c7ac/1282c19:dd:d9:dd:c25:c25b:d00a:c7ac
1742c19:dd:d9:dd:c25:c25b:d00a:c7ad/1282c19:dd:d9:dd:c25:c25b:d00a:c7ad
1752c19:dd:d9:dd:c25:c25b:d00a:c7ae/1282c19:dd:d9:dd:c25:c25b:d00a:c7ae
1762c19:dd:d9:dd:c25:c25b:d00a:c7af/1282c19:dd:d9:dd:c25:c25b:d00a:c7af
1772c19:dd:d9:dd:c25:c25b:d00a:c7b0/1282c19:dd:d9:dd:c25:c25b:d00a:c7b0
1782c19:dd:d9:dd:c25:c25b:d00a:c7b1/1282c19:dd:d9:dd:c25:c25b:d00a:c7b1
1792c19:dd:d9:dd:c25:c25b:d00a:c7b2/1282c19:dd:d9:dd:c25:c25b:d00a:c7b2
1802c19:dd:d9:dd:c25:c25b:d00a:c7b3/1282c19:dd:d9:dd:c25:c25b:d00a:c7b3
1812c19:dd:d9:dd:c25:c25b:d00a:c7b4/1282c19:dd:d9:dd:c25:c25b:d00a:c7b4
1822c19:dd:d9:dd:c25:c25b:d00a:c7b5/1282c19:dd:d9:dd:c25:c25b:d00a:c7b5
1832c19:dd:d9:dd:c25:c25b:d00a:c7b6/1282c19:dd:d9:dd:c25:c25b:d00a:c7b6
1842c19:dd:d9:dd:c25:c25b:d00a:c7b7/1282c19:dd:d9:dd:c25:c25b:d00a:c7b7
1852c19:dd:d9:dd:c25:c25b:d00a:c7b8/1282c19:dd:d9:dd:c25:c25b:d00a:c7b8
1862c19:dd:d9:dd:c25:c25b:d00a:c7b9/1282c19:dd:d9:dd:c25:c25b:d00a:c7b9
1872c19:dd:d9:dd:c25:c25b:d00a:c7ba/1282c19:dd:d9:dd:c25:c25b:d00a:c7ba
1882c19:dd:d9:dd:c25:c25b:d00a:c7bb/1282c19:dd:d9:dd:c25:c25b:d00a:c7bb
1892c19:dd:d9:dd:c25:c25b:d00a:c7bc/1282c19:dd:d9:dd:c25:c25b:d00a:c7bc
1902c19:dd:d9:dd:c25:c25b:d00a:c7bd/1282c19:dd:d9:dd:c25:c25b:d00a:c7bd
1912c19:dd:d9:dd:c25:c25b:d00a:c7be/1282c19:dd:d9:dd:c25:c25b:d00a:c7be
1922c19:dd:d9:dd:c25:c25b:d00a:c7bf/1282c19:dd:d9:dd:c25:c25b:d00a:c7bf
1932c19:dd:d9:dd:c25:c25b:d00a:c7c0/1282c19:dd:d9:dd:c25:c25b:d00a:c7c0
1942c19:dd:d9:dd:c25:c25b:d00a:c7c1/1282c19:dd:d9:dd:c25:c25b:d00a:c7c1
1952c19:dd:d9:dd:c25:c25b:d00a:c7c2/1282c19:dd:d9:dd:c25:c25b:d00a:c7c2
1962c19:dd:d9:dd:c25:c25b:d00a:c7c3/1282c19:dd:d9:dd:c25:c25b:d00a:c7c3
1972c19:dd:d9:dd:c25:c25b:d00a:c7c4/1282c19:dd:d9:dd:c25:c25b:d00a:c7c4
1982c19:dd:d9:dd:c25:c25b:d00a:c7c5/1282c19:dd:d9:dd:c25:c25b:d00a:c7c5
1992c19:dd:d9:dd:c25:c25b:d00a:c7c6/1282c19:dd:d9:dd:c25:c25b:d00a:c7c6
2002c19:dd:d9:dd:c25:c25b:d00a:c7c7/1282c19:dd:d9:dd:c25:c25b:d00a:c7c7
2012c19:dd:d9:dd:c25:c25b:d00a:c7c8/1282c19:dd:d9:dd:c25:c25b:d00a:c7c8
2022c19:dd:d9:dd:c25:c25b:d00a:c7c9/1282c19:dd:d9:dd:c25:c25b:d00a:c7c9
2032c19:dd:d9:dd:c25:c25b:d00a:c7ca/1282c19:dd:d9:dd:c25:c25b:d00a:c7ca
2042c19:dd:d9:dd:c25:c25b:d00a:c7cb/1282c19:dd:d9:dd:c25:c25b:d00a:c7cb
2052c19:dd:d9:dd:c25:c25b:d00a:c7cc/1282c19:dd:d9:dd:c25:c25b:d00a:c7cc
2062c19:dd:d9:dd:c25:c25b:d00a:c7cd/1282c19:dd:d9:dd:c25:c25b:d00a:c7cd
2072c19:dd:d9:dd:c25:c25b:d00a:c7ce/1282c19:dd:d9:dd:c25:c25b:d00a:c7ce
2082c19:dd:d9:dd:c25:c25b:d00a:c7cf/1282c19:dd:d9:dd:c25:c25b:d00a:c7cf
2092c19:dd:d9:dd:c25:c25b:d00a:c7d0/1282c19:dd:d9:dd:c25:c25b:d00a:c7d0
2102c19:dd:d9:dd:c25:c25b:d00a:c7d1/1282c19:dd:d9:dd:c25:c25b:d00a:c7d1
2112c19:dd:d9:dd:c25:c25b:d00a:c7d2/1282c19:dd:d9:dd:c25:c25b:d00a:c7d2
2122c19:dd:d9:dd:c25:c25b:d00a:c7d3/1282c19:dd:d9:dd:c25:c25b:d00a:c7d3
2132c19:dd:d9:dd:c25:c25b:d00a:c7d4/1282c19:dd:d9:dd:c25:c25b:d00a:c7d4
2142c19:dd:d9:dd:c25:c25b:d00a:c7d5/1282c19:dd:d9:dd:c25:c25b:d00a:c7d5
2152c19:dd:d9:dd:c25:c25b:d00a:c7d6/1282c19:dd:d9:dd:c25:c25b:d00a:c7d6
2162c19:dd:d9:dd:c25:c25b:d00a:c7d7/1282c19:dd:d9:dd:c25:c25b:d00a:c7d7
2172c19:dd:d9:dd:c25:c25b:d00a:c7d8/1282c19:dd:d9:dd:c25:c25b:d00a:c7d8
2182c19:dd:d9:dd:c25:c25b:d00a:c7d9/1282c19:dd:d9:dd:c25:c25b:d00a:c7d9
2192c19:dd:d9:dd:c25:c25b:d00a:c7da/1282c19:dd:d9:dd:c25:c25b:d00a:c7da
2202c19:dd:d9:dd:c25:c25b:d00a:c7db/1282c19:dd:d9:dd:c25:c25b:d00a:c7db
2212c19:dd:d9:dd:c25:c25b:d00a:c7dc/1282c19:dd:d9:dd:c25:c25b:d00a:c7dc
2222c19:dd:d9:dd:c25:c25b:d00a:c7dd/1282c19:dd:d9:dd:c25:c25b:d00a:c7dd
2232c19:dd:d9:dd:c25:c25b:d00a:c7de/1282c19:dd:d9:dd:c25:c25b:d00a:c7de
2242c19:dd:d9:dd:c25:c25b:d00a:c7df/1282c19:dd:d9:dd:c25:c25b:d00a:c7df
2252c19:dd:d9:dd:c25:c25b:d00a:c7e0/1282c19:dd:d9:dd:c25:c25b:d00a:c7e0
2262c19:dd:d9:dd:c25:c25b:d00a:c7e1/1282c19:dd:d9:dd:c25:c25b:d00a:c7e1
2272c19:dd:d9:dd:c25:c25b:d00a:c7e2/1282c19:dd:d9:dd:c25:c25b:d00a:c7e2
2282c19:dd:d9:dd:c25:c25b:d00a:c7e3/1282c19:dd:d9:dd:c25:c25b:d00a:c7e3
2292c19:dd:d9:dd:c25:c25b:d00a:c7e4/1282c19:dd:d9:dd:c25:c25b:d00a:c7e4
2302c19:dd:d9:dd:c25:c25b:d00a:c7e5/1282c19:dd:d9:dd:c25:c25b:d00a:c7e5
2312c19:dd:d9:dd:c25:c25b:d00a:c7e6/1282c19:dd:d9:dd:c25:c25b:d00a:c7e6
2322c19:dd:d9:dd:c25:c25b:d00a:c7e7/1282c19:dd:d9:dd:c25:c25b:d00a:c7e7
2332c19:dd:d9:dd:c25:c25b:d00a:c7e8/1282c19:dd:d9:dd:c25:c25b:d00a:c7e8
2342c19:dd:d9:dd:c25:c25b:d00a:c7e9/1282c19:dd:d9:dd:c25:c25b:d00a:c7e9
2352c19:dd:d9:dd:c25:c25b:d00a:c7ea/1282c19:dd:d9:dd:c25:c25b:d00a:c7ea
2362c19:dd:d9:dd:c25:c25b:d00a:c7eb/1282c19:dd:d9:dd:c25:c25b:d00a:c7eb
2372c19:dd:d9:dd:c25:c25b:d00a:c7ec/1282c19:dd:d9:dd:c25:c25b:d00a:c7ec
2382c19:dd:d9:dd:c25:c25b:d00a:c7ed/1282c19:dd:d9:dd:c25:c25b:d00a:c7ed
2392c19:dd:d9:dd:c25:c25b:d00a:c7ee/1282c19:dd:d9:dd:c25:c25b:d00a:c7ee
2402c19:dd:d9:dd:c25:c25b:d00a:c7ef/1282c19:dd:d9:dd:c25:c25b:d00a:c7ef
2412c19:dd:d9:dd:c25:c25b:d00a:c7f0/1282c19:dd:d9:dd:c25:c25b:d00a:c7f0
2422c19:dd:d9:dd:c25:c25b:d00a:c7f1/1282c19:dd:d9:dd:c25:c25b:d00a:c7f1
2432c19:dd:d9:dd:c25:c25b:d00a:c7f2/1282c19:dd:d9:dd:c25:c25b:d00a:c7f2
2442c19:dd:d9:dd:c25:c25b:d00a:c7f3/1282c19:dd:d9:dd:c25:c25b:d00a:c7f3
2452c19:dd:d9:dd:c25:c25b:d00a:c7f4/1282c19:dd:d9:dd:c25:c25b:d00a:c7f4
2462c19:dd:d9:dd:c25:c25b:d00a:c7f5/1282c19:dd:d9:dd:c25:c25b:d00a:c7f5
2472c19:dd:d9:dd:c25:c25b:d00a:c7f6/1282c19:dd:d9:dd:c25:c25b:d00a:c7f6
2482c19:dd:d9:dd:c25:c25b:d00a:c7f7/1282c19:dd:d9:dd:c25:c25b:d00a:c7f7
2492c19:dd:d9:dd:c25:c25b:d00a:c7f8/1282c19:dd:d9:dd:c25:c25b:d00a:c7f8
2502c19:dd:d9:dd:c25:c25b:d00a:c7f9/1282c19:dd:d9:dd:c25:c25b:d00a:c7f9
2512c19:dd:d9:dd:c25:c25b:d00a:c7fa/1282c19:dd:d9:dd:c25:c25b:d00a:c7fa
2522c19:dd:d9:dd:c25:c25b:d00a:c7fb/1282c19:dd:d9:dd:c25:c25b:d00a:c7fb
2532c19:dd:d9:dd:c25:c25b:d00a:c7fc/1282c19:dd:d9:dd:c25:c25b:d00a:c7fc
2542c19:dd:d9:dd:c25:c25b:d00a:c7fd/1282c19:dd:d9:dd:c25:c25b:d00a:c7fd
2552c19:dd:d9:dd:c25:c25b:d00a:c7fe/1282c19:dd:d9:dd:c25:c25b:d00a:c7fe
2562c19:dd:d9:dd:c25:c25b:d00a:c7ff/1282c19:dd:d9:dd:c25:c25b:d00a:c7ff

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.