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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:c25:94de:f700/120
First address
2c19:dd:d9:dd:c25:c25:94de:f700
Last address
2c19:dd:d9:dd:c25:c25:94de:f7ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:f700
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
7.f.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:94de:f700/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:f700/1282c19:dd:d9:dd:c25:c25:94de:f700
22c19:dd:d9:dd:c25:c25:94de:f701/1282c19:dd:d9:dd:c25:c25:94de:f701
32c19:dd:d9:dd:c25:c25:94de:f702/1282c19:dd:d9:dd:c25:c25:94de:f702
42c19:dd:d9:dd:c25:c25:94de:f703/1282c19:dd:d9:dd:c25:c25:94de:f703
52c19:dd:d9:dd:c25:c25:94de:f704/1282c19:dd:d9:dd:c25:c25:94de:f704
62c19:dd:d9:dd:c25:c25:94de:f705/1282c19:dd:d9:dd:c25:c25:94de:f705
72c19:dd:d9:dd:c25:c25:94de:f706/1282c19:dd:d9:dd:c25:c25:94de:f706
82c19:dd:d9:dd:c25:c25:94de:f707/1282c19:dd:d9:dd:c25:c25:94de:f707
92c19:dd:d9:dd:c25:c25:94de:f708/1282c19:dd:d9:dd:c25:c25:94de:f708
102c19:dd:d9:dd:c25:c25:94de:f709/1282c19:dd:d9:dd:c25:c25:94de:f709
112c19:dd:d9:dd:c25:c25:94de:f70a/1282c19:dd:d9:dd:c25:c25:94de:f70a
122c19:dd:d9:dd:c25:c25:94de:f70b/1282c19:dd:d9:dd:c25:c25:94de:f70b
132c19:dd:d9:dd:c25:c25:94de:f70c/1282c19:dd:d9:dd:c25:c25:94de:f70c
142c19:dd:d9:dd:c25:c25:94de:f70d/1282c19:dd:d9:dd:c25:c25:94de:f70d
152c19:dd:d9:dd:c25:c25:94de:f70e/1282c19:dd:d9:dd:c25:c25:94de:f70e
162c19:dd:d9:dd:c25:c25:94de:f70f/1282c19:dd:d9:dd:c25:c25:94de:f70f
172c19:dd:d9:dd:c25:c25:94de:f710/1282c19:dd:d9:dd:c25:c25:94de:f710
182c19:dd:d9:dd:c25:c25:94de:f711/1282c19:dd:d9:dd:c25:c25:94de:f711
192c19:dd:d9:dd:c25:c25:94de:f712/1282c19:dd:d9:dd:c25:c25:94de:f712
202c19:dd:d9:dd:c25:c25:94de:f713/1282c19:dd:d9:dd:c25:c25:94de:f713
212c19:dd:d9:dd:c25:c25:94de:f714/1282c19:dd:d9:dd:c25:c25:94de:f714
222c19:dd:d9:dd:c25:c25:94de:f715/1282c19:dd:d9:dd:c25:c25:94de:f715
232c19:dd:d9:dd:c25:c25:94de:f716/1282c19:dd:d9:dd:c25:c25:94de:f716
242c19:dd:d9:dd:c25:c25:94de:f717/1282c19:dd:d9:dd:c25:c25:94de:f717
252c19:dd:d9:dd:c25:c25:94de:f718/1282c19:dd:d9:dd:c25:c25:94de:f718
262c19:dd:d9:dd:c25:c25:94de:f719/1282c19:dd:d9:dd:c25:c25:94de:f719
272c19:dd:d9:dd:c25:c25:94de:f71a/1282c19:dd:d9:dd:c25:c25:94de:f71a
282c19:dd:d9:dd:c25:c25:94de:f71b/1282c19:dd:d9:dd:c25:c25:94de:f71b
292c19:dd:d9:dd:c25:c25:94de:f71c/1282c19:dd:d9:dd:c25:c25:94de:f71c
302c19:dd:d9:dd:c25:c25:94de:f71d/1282c19:dd:d9:dd:c25:c25:94de:f71d
312c19:dd:d9:dd:c25:c25:94de:f71e/1282c19:dd:d9:dd:c25:c25:94de:f71e
322c19:dd:d9:dd:c25:c25:94de:f71f/1282c19:dd:d9:dd:c25:c25:94de:f71f
332c19:dd:d9:dd:c25:c25:94de:f720/1282c19:dd:d9:dd:c25:c25:94de:f720
342c19:dd:d9:dd:c25:c25:94de:f721/1282c19:dd:d9:dd:c25:c25:94de:f721
352c19:dd:d9:dd:c25:c25:94de:f722/1282c19:dd:d9:dd:c25:c25:94de:f722
362c19:dd:d9:dd:c25:c25:94de:f723/1282c19:dd:d9:dd:c25:c25:94de:f723
372c19:dd:d9:dd:c25:c25:94de:f724/1282c19:dd:d9:dd:c25:c25:94de:f724
382c19:dd:d9:dd:c25:c25:94de:f725/1282c19:dd:d9:dd:c25:c25:94de:f725
392c19:dd:d9:dd:c25:c25:94de:f726/1282c19:dd:d9:dd:c25:c25:94de:f726
402c19:dd:d9:dd:c25:c25:94de:f727/1282c19:dd:d9:dd:c25:c25:94de:f727
412c19:dd:d9:dd:c25:c25:94de:f728/1282c19:dd:d9:dd:c25:c25:94de:f728
422c19:dd:d9:dd:c25:c25:94de:f729/1282c19:dd:d9:dd:c25:c25:94de:f729
432c19:dd:d9:dd:c25:c25:94de:f72a/1282c19:dd:d9:dd:c25:c25:94de:f72a
442c19:dd:d9:dd:c25:c25:94de:f72b/1282c19:dd:d9:dd:c25:c25:94de:f72b
452c19:dd:d9:dd:c25:c25:94de:f72c/1282c19:dd:d9:dd:c25:c25:94de:f72c
462c19:dd:d9:dd:c25:c25:94de:f72d/1282c19:dd:d9:dd:c25:c25:94de:f72d
472c19:dd:d9:dd:c25:c25:94de:f72e/1282c19:dd:d9:dd:c25:c25:94de:f72e
482c19:dd:d9:dd:c25:c25:94de:f72f/1282c19:dd:d9:dd:c25:c25:94de:f72f
492c19:dd:d9:dd:c25:c25:94de:f730/1282c19:dd:d9:dd:c25:c25:94de:f730
502c19:dd:d9:dd:c25:c25:94de:f731/1282c19:dd:d9:dd:c25:c25:94de:f731
512c19:dd:d9:dd:c25:c25:94de:f732/1282c19:dd:d9:dd:c25:c25:94de:f732
522c19:dd:d9:dd:c25:c25:94de:f733/1282c19:dd:d9:dd:c25:c25:94de:f733
532c19:dd:d9:dd:c25:c25:94de:f734/1282c19:dd:d9:dd:c25:c25:94de:f734
542c19:dd:d9:dd:c25:c25:94de:f735/1282c19:dd:d9:dd:c25:c25:94de:f735
552c19:dd:d9:dd:c25:c25:94de:f736/1282c19:dd:d9:dd:c25:c25:94de:f736
562c19:dd:d9:dd:c25:c25:94de:f737/1282c19:dd:d9:dd:c25:c25:94de:f737
572c19:dd:d9:dd:c25:c25:94de:f738/1282c19:dd:d9:dd:c25:c25:94de:f738
582c19:dd:d9:dd:c25:c25:94de:f739/1282c19:dd:d9:dd:c25:c25:94de:f739
592c19:dd:d9:dd:c25:c25:94de:f73a/1282c19:dd:d9:dd:c25:c25:94de:f73a
602c19:dd:d9:dd:c25:c25:94de:f73b/1282c19:dd:d9:dd:c25:c25:94de:f73b
612c19:dd:d9:dd:c25:c25:94de:f73c/1282c19:dd:d9:dd:c25:c25:94de:f73c
622c19:dd:d9:dd:c25:c25:94de:f73d/1282c19:dd:d9:dd:c25:c25:94de:f73d
632c19:dd:d9:dd:c25:c25:94de:f73e/1282c19:dd:d9:dd:c25:c25:94de:f73e
642c19:dd:d9:dd:c25:c25:94de:f73f/1282c19:dd:d9:dd:c25:c25:94de:f73f
652c19:dd:d9:dd:c25:c25:94de:f740/1282c19:dd:d9:dd:c25:c25:94de:f740
662c19:dd:d9:dd:c25:c25:94de:f741/1282c19:dd:d9:dd:c25:c25:94de:f741
672c19:dd:d9:dd:c25:c25:94de:f742/1282c19:dd:d9:dd:c25:c25:94de:f742
682c19:dd:d9:dd:c25:c25:94de:f743/1282c19:dd:d9:dd:c25:c25:94de:f743
692c19:dd:d9:dd:c25:c25:94de:f744/1282c19:dd:d9:dd:c25:c25:94de:f744
702c19:dd:d9:dd:c25:c25:94de:f745/1282c19:dd:d9:dd:c25:c25:94de:f745
712c19:dd:d9:dd:c25:c25:94de:f746/1282c19:dd:d9:dd:c25:c25:94de:f746
722c19:dd:d9:dd:c25:c25:94de:f747/1282c19:dd:d9:dd:c25:c25:94de:f747
732c19:dd:d9:dd:c25:c25:94de:f748/1282c19:dd:d9:dd:c25:c25:94de:f748
742c19:dd:d9:dd:c25:c25:94de:f749/1282c19:dd:d9:dd:c25:c25:94de:f749
752c19:dd:d9:dd:c25:c25:94de:f74a/1282c19:dd:d9:dd:c25:c25:94de:f74a
762c19:dd:d9:dd:c25:c25:94de:f74b/1282c19:dd:d9:dd:c25:c25:94de:f74b
772c19:dd:d9:dd:c25:c25:94de:f74c/1282c19:dd:d9:dd:c25:c25:94de:f74c
782c19:dd:d9:dd:c25:c25:94de:f74d/1282c19:dd:d9:dd:c25:c25:94de:f74d
792c19:dd:d9:dd:c25:c25:94de:f74e/1282c19:dd:d9:dd:c25:c25:94de:f74e
802c19:dd:d9:dd:c25:c25:94de:f74f/1282c19:dd:d9:dd:c25:c25:94de:f74f
812c19:dd:d9:dd:c25:c25:94de:f750/1282c19:dd:d9:dd:c25:c25:94de:f750
822c19:dd:d9:dd:c25:c25:94de:f751/1282c19:dd:d9:dd:c25:c25:94de:f751
832c19:dd:d9:dd:c25:c25:94de:f752/1282c19:dd:d9:dd:c25:c25:94de:f752
842c19:dd:d9:dd:c25:c25:94de:f753/1282c19:dd:d9:dd:c25:c25:94de:f753
852c19:dd:d9:dd:c25:c25:94de:f754/1282c19:dd:d9:dd:c25:c25:94de:f754
862c19:dd:d9:dd:c25:c25:94de:f755/1282c19:dd:d9:dd:c25:c25:94de:f755
872c19:dd:d9:dd:c25:c25:94de:f756/1282c19:dd:d9:dd:c25:c25:94de:f756
882c19:dd:d9:dd:c25:c25:94de:f757/1282c19:dd:d9:dd:c25:c25:94de:f757
892c19:dd:d9:dd:c25:c25:94de:f758/1282c19:dd:d9:dd:c25:c25:94de:f758
902c19:dd:d9:dd:c25:c25:94de:f759/1282c19:dd:d9:dd:c25:c25:94de:f759
912c19:dd:d9:dd:c25:c25:94de:f75a/1282c19:dd:d9:dd:c25:c25:94de:f75a
922c19:dd:d9:dd:c25:c25:94de:f75b/1282c19:dd:d9:dd:c25:c25:94de:f75b
932c19:dd:d9:dd:c25:c25:94de:f75c/1282c19:dd:d9:dd:c25:c25:94de:f75c
942c19:dd:d9:dd:c25:c25:94de:f75d/1282c19:dd:d9:dd:c25:c25:94de:f75d
952c19:dd:d9:dd:c25:c25:94de:f75e/1282c19:dd:d9:dd:c25:c25:94de:f75e
962c19:dd:d9:dd:c25:c25:94de:f75f/1282c19:dd:d9:dd:c25:c25:94de:f75f
972c19:dd:d9:dd:c25:c25:94de:f760/1282c19:dd:d9:dd:c25:c25:94de:f760
982c19:dd:d9:dd:c25:c25:94de:f761/1282c19:dd:d9:dd:c25:c25:94de:f761
992c19:dd:d9:dd:c25:c25:94de:f762/1282c19:dd:d9:dd:c25:c25:94de:f762
1002c19:dd:d9:dd:c25:c25:94de:f763/1282c19:dd:d9:dd:c25:c25:94de:f763
1012c19:dd:d9:dd:c25:c25:94de:f764/1282c19:dd:d9:dd:c25:c25:94de:f764
1022c19:dd:d9:dd:c25:c25:94de:f765/1282c19:dd:d9:dd:c25:c25:94de:f765
1032c19:dd:d9:dd:c25:c25:94de:f766/1282c19:dd:d9:dd:c25:c25:94de:f766
1042c19:dd:d9:dd:c25:c25:94de:f767/1282c19:dd:d9:dd:c25:c25:94de:f767
1052c19:dd:d9:dd:c25:c25:94de:f768/1282c19:dd:d9:dd:c25:c25:94de:f768
1062c19:dd:d9:dd:c25:c25:94de:f769/1282c19:dd:d9:dd:c25:c25:94de:f769
1072c19:dd:d9:dd:c25:c25:94de:f76a/1282c19:dd:d9:dd:c25:c25:94de:f76a
1082c19:dd:d9:dd:c25:c25:94de:f76b/1282c19:dd:d9:dd:c25:c25:94de:f76b
1092c19:dd:d9:dd:c25:c25:94de:f76c/1282c19:dd:d9:dd:c25:c25:94de:f76c
1102c19:dd:d9:dd:c25:c25:94de:f76d/1282c19:dd:d9:dd:c25:c25:94de:f76d
1112c19:dd:d9:dd:c25:c25:94de:f76e/1282c19:dd:d9:dd:c25:c25:94de:f76e
1122c19:dd:d9:dd:c25:c25:94de:f76f/1282c19:dd:d9:dd:c25:c25:94de:f76f
1132c19:dd:d9:dd:c25:c25:94de:f770/1282c19:dd:d9:dd:c25:c25:94de:f770
1142c19:dd:d9:dd:c25:c25:94de:f771/1282c19:dd:d9:dd:c25:c25:94de:f771
1152c19:dd:d9:dd:c25:c25:94de:f772/1282c19:dd:d9:dd:c25:c25:94de:f772
1162c19:dd:d9:dd:c25:c25:94de:f773/1282c19:dd:d9:dd:c25:c25:94de:f773
1172c19:dd:d9:dd:c25:c25:94de:f774/1282c19:dd:d9:dd:c25:c25:94de:f774
1182c19:dd:d9:dd:c25:c25:94de:f775/1282c19:dd:d9:dd:c25:c25:94de:f775
1192c19:dd:d9:dd:c25:c25:94de:f776/1282c19:dd:d9:dd:c25:c25:94de:f776
1202c19:dd:d9:dd:c25:c25:94de:f777/1282c19:dd:d9:dd:c25:c25:94de:f777
1212c19:dd:d9:dd:c25:c25:94de:f778/1282c19:dd:d9:dd:c25:c25:94de:f778
1222c19:dd:d9:dd:c25:c25:94de:f779/1282c19:dd:d9:dd:c25:c25:94de:f779
1232c19:dd:d9:dd:c25:c25:94de:f77a/1282c19:dd:d9:dd:c25:c25:94de:f77a
1242c19:dd:d9:dd:c25:c25:94de:f77b/1282c19:dd:d9:dd:c25:c25:94de:f77b
1252c19:dd:d9:dd:c25:c25:94de:f77c/1282c19:dd:d9:dd:c25:c25:94de:f77c
1262c19:dd:d9:dd:c25:c25:94de:f77d/1282c19:dd:d9:dd:c25:c25:94de:f77d
1272c19:dd:d9:dd:c25:c25:94de:f77e/1282c19:dd:d9:dd:c25:c25:94de:f77e
1282c19:dd:d9:dd:c25:c25:94de:f77f/1282c19:dd:d9:dd:c25:c25:94de:f77f
1292c19:dd:d9:dd:c25:c25:94de:f780/1282c19:dd:d9:dd:c25:c25:94de:f780
1302c19:dd:d9:dd:c25:c25:94de:f781/1282c19:dd:d9:dd:c25:c25:94de:f781
1312c19:dd:d9:dd:c25:c25:94de:f782/1282c19:dd:d9:dd:c25:c25:94de:f782
1322c19:dd:d9:dd:c25:c25:94de:f783/1282c19:dd:d9:dd:c25:c25:94de:f783
1332c19:dd:d9:dd:c25:c25:94de:f784/1282c19:dd:d9:dd:c25:c25:94de:f784
1342c19:dd:d9:dd:c25:c25:94de:f785/1282c19:dd:d9:dd:c25:c25:94de:f785
1352c19:dd:d9:dd:c25:c25:94de:f786/1282c19:dd:d9:dd:c25:c25:94de:f786
1362c19:dd:d9:dd:c25:c25:94de:f787/1282c19:dd:d9:dd:c25:c25:94de:f787
1372c19:dd:d9:dd:c25:c25:94de:f788/1282c19:dd:d9:dd:c25:c25:94de:f788
1382c19:dd:d9:dd:c25:c25:94de:f789/1282c19:dd:d9:dd:c25:c25:94de:f789
1392c19:dd:d9:dd:c25:c25:94de:f78a/1282c19:dd:d9:dd:c25:c25:94de:f78a
1402c19:dd:d9:dd:c25:c25:94de:f78b/1282c19:dd:d9:dd:c25:c25:94de:f78b
1412c19:dd:d9:dd:c25:c25:94de:f78c/1282c19:dd:d9:dd:c25:c25:94de:f78c
1422c19:dd:d9:dd:c25:c25:94de:f78d/1282c19:dd:d9:dd:c25:c25:94de:f78d
1432c19:dd:d9:dd:c25:c25:94de:f78e/1282c19:dd:d9:dd:c25:c25:94de:f78e
1442c19:dd:d9:dd:c25:c25:94de:f78f/1282c19:dd:d9:dd:c25:c25:94de:f78f
1452c19:dd:d9:dd:c25:c25:94de:f790/1282c19:dd:d9:dd:c25:c25:94de:f790
1462c19:dd:d9:dd:c25:c25:94de:f791/1282c19:dd:d9:dd:c25:c25:94de:f791
1472c19:dd:d9:dd:c25:c25:94de:f792/1282c19:dd:d9:dd:c25:c25:94de:f792
1482c19:dd:d9:dd:c25:c25:94de:f793/1282c19:dd:d9:dd:c25:c25:94de:f793
1492c19:dd:d9:dd:c25:c25:94de:f794/1282c19:dd:d9:dd:c25:c25:94de:f794
1502c19:dd:d9:dd:c25:c25:94de:f795/1282c19:dd:d9:dd:c25:c25:94de:f795
1512c19:dd:d9:dd:c25:c25:94de:f796/1282c19:dd:d9:dd:c25:c25:94de:f796
1522c19:dd:d9:dd:c25:c25:94de:f797/1282c19:dd:d9:dd:c25:c25:94de:f797
1532c19:dd:d9:dd:c25:c25:94de:f798/1282c19:dd:d9:dd:c25:c25:94de:f798
1542c19:dd:d9:dd:c25:c25:94de:f799/1282c19:dd:d9:dd:c25:c25:94de:f799
1552c19:dd:d9:dd:c25:c25:94de:f79a/1282c19:dd:d9:dd:c25:c25:94de:f79a
1562c19:dd:d9:dd:c25:c25:94de:f79b/1282c19:dd:d9:dd:c25:c25:94de:f79b
1572c19:dd:d9:dd:c25:c25:94de:f79c/1282c19:dd:d9:dd:c25:c25:94de:f79c
1582c19:dd:d9:dd:c25:c25:94de:f79d/1282c19:dd:d9:dd:c25:c25:94de:f79d
1592c19:dd:d9:dd:c25:c25:94de:f79e/1282c19:dd:d9:dd:c25:c25:94de:f79e
1602c19:dd:d9:dd:c25:c25:94de:f79f/1282c19:dd:d9:dd:c25:c25:94de:f79f
1612c19:dd:d9:dd:c25:c25:94de:f7a0/1282c19:dd:d9:dd:c25:c25:94de:f7a0
1622c19:dd:d9:dd:c25:c25:94de:f7a1/1282c19:dd:d9:dd:c25:c25:94de:f7a1
1632c19:dd:d9:dd:c25:c25:94de:f7a2/1282c19:dd:d9:dd:c25:c25:94de:f7a2
1642c19:dd:d9:dd:c25:c25:94de:f7a3/1282c19:dd:d9:dd:c25:c25:94de:f7a3
1652c19:dd:d9:dd:c25:c25:94de:f7a4/1282c19:dd:d9:dd:c25:c25:94de:f7a4
1662c19:dd:d9:dd:c25:c25:94de:f7a5/1282c19:dd:d9:dd:c25:c25:94de:f7a5
1672c19:dd:d9:dd:c25:c25:94de:f7a6/1282c19:dd:d9:dd:c25:c25:94de:f7a6
1682c19:dd:d9:dd:c25:c25:94de:f7a7/1282c19:dd:d9:dd:c25:c25:94de:f7a7
1692c19:dd:d9:dd:c25:c25:94de:f7a8/1282c19:dd:d9:dd:c25:c25:94de:f7a8
1702c19:dd:d9:dd:c25:c25:94de:f7a9/1282c19:dd:d9:dd:c25:c25:94de:f7a9
1712c19:dd:d9:dd:c25:c25:94de:f7aa/1282c19:dd:d9:dd:c25:c25:94de:f7aa
1722c19:dd:d9:dd:c25:c25:94de:f7ab/1282c19:dd:d9:dd:c25:c25:94de:f7ab
1732c19:dd:d9:dd:c25:c25:94de:f7ac/1282c19:dd:d9:dd:c25:c25:94de:f7ac
1742c19:dd:d9:dd:c25:c25:94de:f7ad/1282c19:dd:d9:dd:c25:c25:94de:f7ad
1752c19:dd:d9:dd:c25:c25:94de:f7ae/1282c19:dd:d9:dd:c25:c25:94de:f7ae
1762c19:dd:d9:dd:c25:c25:94de:f7af/1282c19:dd:d9:dd:c25:c25:94de:f7af
1772c19:dd:d9:dd:c25:c25:94de:f7b0/1282c19:dd:d9:dd:c25:c25:94de:f7b0
1782c19:dd:d9:dd:c25:c25:94de:f7b1/1282c19:dd:d9:dd:c25:c25:94de:f7b1
1792c19:dd:d9:dd:c25:c25:94de:f7b2/1282c19:dd:d9:dd:c25:c25:94de:f7b2
1802c19:dd:d9:dd:c25:c25:94de:f7b3/1282c19:dd:d9:dd:c25:c25:94de:f7b3
1812c19:dd:d9:dd:c25:c25:94de:f7b4/1282c19:dd:d9:dd:c25:c25:94de:f7b4
1822c19:dd:d9:dd:c25:c25:94de:f7b5/1282c19:dd:d9:dd:c25:c25:94de:f7b5
1832c19:dd:d9:dd:c25:c25:94de:f7b6/1282c19:dd:d9:dd:c25:c25:94de:f7b6
1842c19:dd:d9:dd:c25:c25:94de:f7b7/1282c19:dd:d9:dd:c25:c25:94de:f7b7
1852c19:dd:d9:dd:c25:c25:94de:f7b8/1282c19:dd:d9:dd:c25:c25:94de:f7b8
1862c19:dd:d9:dd:c25:c25:94de:f7b9/1282c19:dd:d9:dd:c25:c25:94de:f7b9
1872c19:dd:d9:dd:c25:c25:94de:f7ba/1282c19:dd:d9:dd:c25:c25:94de:f7ba
1882c19:dd:d9:dd:c25:c25:94de:f7bb/1282c19:dd:d9:dd:c25:c25:94de:f7bb
1892c19:dd:d9:dd:c25:c25:94de:f7bc/1282c19:dd:d9:dd:c25:c25:94de:f7bc
1902c19:dd:d9:dd:c25:c25:94de:f7bd/1282c19:dd:d9:dd:c25:c25:94de:f7bd
1912c19:dd:d9:dd:c25:c25:94de:f7be/1282c19:dd:d9:dd:c25:c25:94de:f7be
1922c19:dd:d9:dd:c25:c25:94de:f7bf/1282c19:dd:d9:dd:c25:c25:94de:f7bf
1932c19:dd:d9:dd:c25:c25:94de:f7c0/1282c19:dd:d9:dd:c25:c25:94de:f7c0
1942c19:dd:d9:dd:c25:c25:94de:f7c1/1282c19:dd:d9:dd:c25:c25:94de:f7c1
1952c19:dd:d9:dd:c25:c25:94de:f7c2/1282c19:dd:d9:dd:c25:c25:94de:f7c2
1962c19:dd:d9:dd:c25:c25:94de:f7c3/1282c19:dd:d9:dd:c25:c25:94de:f7c3
1972c19:dd:d9:dd:c25:c25:94de:f7c4/1282c19:dd:d9:dd:c25:c25:94de:f7c4
1982c19:dd:d9:dd:c25:c25:94de:f7c5/1282c19:dd:d9:dd:c25:c25:94de:f7c5
1992c19:dd:d9:dd:c25:c25:94de:f7c6/1282c19:dd:d9:dd:c25:c25:94de:f7c6
2002c19:dd:d9:dd:c25:c25:94de:f7c7/1282c19:dd:d9:dd:c25:c25:94de:f7c7
2012c19:dd:d9:dd:c25:c25:94de:f7c8/1282c19:dd:d9:dd:c25:c25:94de:f7c8
2022c19:dd:d9:dd:c25:c25:94de:f7c9/1282c19:dd:d9:dd:c25:c25:94de:f7c9
2032c19:dd:d9:dd:c25:c25:94de:f7ca/1282c19:dd:d9:dd:c25:c25:94de:f7ca
2042c19:dd:d9:dd:c25:c25:94de:f7cb/1282c19:dd:d9:dd:c25:c25:94de:f7cb
2052c19:dd:d9:dd:c25:c25:94de:f7cc/1282c19:dd:d9:dd:c25:c25:94de:f7cc
2062c19:dd:d9:dd:c25:c25:94de:f7cd/1282c19:dd:d9:dd:c25:c25:94de:f7cd
2072c19:dd:d9:dd:c25:c25:94de:f7ce/1282c19:dd:d9:dd:c25:c25:94de:f7ce
2082c19:dd:d9:dd:c25:c25:94de:f7cf/1282c19:dd:d9:dd:c25:c25:94de:f7cf
2092c19:dd:d9:dd:c25:c25:94de:f7d0/1282c19:dd:d9:dd:c25:c25:94de:f7d0
2102c19:dd:d9:dd:c25:c25:94de:f7d1/1282c19:dd:d9:dd:c25:c25:94de:f7d1
2112c19:dd:d9:dd:c25:c25:94de:f7d2/1282c19:dd:d9:dd:c25:c25:94de:f7d2
2122c19:dd:d9:dd:c25:c25:94de:f7d3/1282c19:dd:d9:dd:c25:c25:94de:f7d3
2132c19:dd:d9:dd:c25:c25:94de:f7d4/1282c19:dd:d9:dd:c25:c25:94de:f7d4
2142c19:dd:d9:dd:c25:c25:94de:f7d5/1282c19:dd:d9:dd:c25:c25:94de:f7d5
2152c19:dd:d9:dd:c25:c25:94de:f7d6/1282c19:dd:d9:dd:c25:c25:94de:f7d6
2162c19:dd:d9:dd:c25:c25:94de:f7d7/1282c19:dd:d9:dd:c25:c25:94de:f7d7
2172c19:dd:d9:dd:c25:c25:94de:f7d8/1282c19:dd:d9:dd:c25:c25:94de:f7d8
2182c19:dd:d9:dd:c25:c25:94de:f7d9/1282c19:dd:d9:dd:c25:c25:94de:f7d9
2192c19:dd:d9:dd:c25:c25:94de:f7da/1282c19:dd:d9:dd:c25:c25:94de:f7da
2202c19:dd:d9:dd:c25:c25:94de:f7db/1282c19:dd:d9:dd:c25:c25:94de:f7db
2212c19:dd:d9:dd:c25:c25:94de:f7dc/1282c19:dd:d9:dd:c25:c25:94de:f7dc
2222c19:dd:d9:dd:c25:c25:94de:f7dd/1282c19:dd:d9:dd:c25:c25:94de:f7dd
2232c19:dd:d9:dd:c25:c25:94de:f7de/1282c19:dd:d9:dd:c25:c25:94de:f7de
2242c19:dd:d9:dd:c25:c25:94de:f7df/1282c19:dd:d9:dd:c25:c25:94de:f7df
2252c19:dd:d9:dd:c25:c25:94de:f7e0/1282c19:dd:d9:dd:c25:c25:94de:f7e0
2262c19:dd:d9:dd:c25:c25:94de:f7e1/1282c19:dd:d9:dd:c25:c25:94de:f7e1
2272c19:dd:d9:dd:c25:c25:94de:f7e2/1282c19:dd:d9:dd:c25:c25:94de:f7e2
2282c19:dd:d9:dd:c25:c25:94de:f7e3/1282c19:dd:d9:dd:c25:c25:94de:f7e3
2292c19:dd:d9:dd:c25:c25:94de:f7e4/1282c19:dd:d9:dd:c25:c25:94de:f7e4
2302c19:dd:d9:dd:c25:c25:94de:f7e5/1282c19:dd:d9:dd:c25:c25:94de:f7e5
2312c19:dd:d9:dd:c25:c25:94de:f7e6/1282c19:dd:d9:dd:c25:c25:94de:f7e6
2322c19:dd:d9:dd:c25:c25:94de:f7e7/1282c19:dd:d9:dd:c25:c25:94de:f7e7
2332c19:dd:d9:dd:c25:c25:94de:f7e8/1282c19:dd:d9:dd:c25:c25:94de:f7e8
2342c19:dd:d9:dd:c25:c25:94de:f7e9/1282c19:dd:d9:dd:c25:c25:94de:f7e9
2352c19:dd:d9:dd:c25:c25:94de:f7ea/1282c19:dd:d9:dd:c25:c25:94de:f7ea
2362c19:dd:d9:dd:c25:c25:94de:f7eb/1282c19:dd:d9:dd:c25:c25:94de:f7eb
2372c19:dd:d9:dd:c25:c25:94de:f7ec/1282c19:dd:d9:dd:c25:c25:94de:f7ec
2382c19:dd:d9:dd:c25:c25:94de:f7ed/1282c19:dd:d9:dd:c25:c25:94de:f7ed
2392c19:dd:d9:dd:c25:c25:94de:f7ee/1282c19:dd:d9:dd:c25:c25:94de:f7ee
2402c19:dd:d9:dd:c25:c25:94de:f7ef/1282c19:dd:d9:dd:c25:c25:94de:f7ef
2412c19:dd:d9:dd:c25:c25:94de:f7f0/1282c19:dd:d9:dd:c25:c25:94de:f7f0
2422c19:dd:d9:dd:c25:c25:94de:f7f1/1282c19:dd:d9:dd:c25:c25:94de:f7f1
2432c19:dd:d9:dd:c25:c25:94de:f7f2/1282c19:dd:d9:dd:c25:c25:94de:f7f2
2442c19:dd:d9:dd:c25:c25:94de:f7f3/1282c19:dd:d9:dd:c25:c25:94de:f7f3
2452c19:dd:d9:dd:c25:c25:94de:f7f4/1282c19:dd:d9:dd:c25:c25:94de:f7f4
2462c19:dd:d9:dd:c25:c25:94de:f7f5/1282c19:dd:d9:dd:c25:c25:94de:f7f5
2472c19:dd:d9:dd:c25:c25:94de:f7f6/1282c19:dd:d9:dd:c25:c25:94de:f7f6
2482c19:dd:d9:dd:c25:c25:94de:f7f7/1282c19:dd:d9:dd:c25:c25:94de:f7f7
2492c19:dd:d9:dd:c25:c25:94de:f7f8/1282c19:dd:d9:dd:c25:c25:94de:f7f8
2502c19:dd:d9:dd:c25:c25:94de:f7f9/1282c19:dd:d9:dd:c25:c25:94de:f7f9
2512c19:dd:d9:dd:c25:c25:94de:f7fa/1282c19:dd:d9:dd:c25:c25:94de:f7fa
2522c19:dd:d9:dd:c25:c25:94de:f7fb/1282c19:dd:d9:dd:c25:c25:94de:f7fb
2532c19:dd:d9:dd:c25:c25:94de:f7fc/1282c19:dd:d9:dd:c25:c25:94de:f7fc
2542c19:dd:d9:dd:c25:c25:94de:f7fd/1282c19:dd:d9:dd:c25:c25:94de:f7fd
2552c19:dd:d9:dd:c25:c25:94de:f7fe/1282c19:dd:d9:dd:c25:c25:94de:f7fe
2562c19:dd:d9:dd:c25:c25:94de:f7ff/1282c19:dd:d9:dd:c25:c25:94de:f7ff

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.