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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:ffbb:d700/120
First address
2c19:dd:d9:dd:c25:c25:ffbb:d700
Last address
2c19:dd:d9:dd:c25:c25:ffbb:d7ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:ffbb:d700
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
7.d.b.b.f.f.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:ffbb:d700/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:ffbb:d700/1282c19:dd:d9:dd:c25:c25:ffbb:d700
22c19:dd:d9:dd:c25:c25:ffbb:d701/1282c19:dd:d9:dd:c25:c25:ffbb:d701
32c19:dd:d9:dd:c25:c25:ffbb:d702/1282c19:dd:d9:dd:c25:c25:ffbb:d702
42c19:dd:d9:dd:c25:c25:ffbb:d703/1282c19:dd:d9:dd:c25:c25:ffbb:d703
52c19:dd:d9:dd:c25:c25:ffbb:d704/1282c19:dd:d9:dd:c25:c25:ffbb:d704
62c19:dd:d9:dd:c25:c25:ffbb:d705/1282c19:dd:d9:dd:c25:c25:ffbb:d705
72c19:dd:d9:dd:c25:c25:ffbb:d706/1282c19:dd:d9:dd:c25:c25:ffbb:d706
82c19:dd:d9:dd:c25:c25:ffbb:d707/1282c19:dd:d9:dd:c25:c25:ffbb:d707
92c19:dd:d9:dd:c25:c25:ffbb:d708/1282c19:dd:d9:dd:c25:c25:ffbb:d708
102c19:dd:d9:dd:c25:c25:ffbb:d709/1282c19:dd:d9:dd:c25:c25:ffbb:d709
112c19:dd:d9:dd:c25:c25:ffbb:d70a/1282c19:dd:d9:dd:c25:c25:ffbb:d70a
122c19:dd:d9:dd:c25:c25:ffbb:d70b/1282c19:dd:d9:dd:c25:c25:ffbb:d70b
132c19:dd:d9:dd:c25:c25:ffbb:d70c/1282c19:dd:d9:dd:c25:c25:ffbb:d70c
142c19:dd:d9:dd:c25:c25:ffbb:d70d/1282c19:dd:d9:dd:c25:c25:ffbb:d70d
152c19:dd:d9:dd:c25:c25:ffbb:d70e/1282c19:dd:d9:dd:c25:c25:ffbb:d70e
162c19:dd:d9:dd:c25:c25:ffbb:d70f/1282c19:dd:d9:dd:c25:c25:ffbb:d70f
172c19:dd:d9:dd:c25:c25:ffbb:d710/1282c19:dd:d9:dd:c25:c25:ffbb:d710
182c19:dd:d9:dd:c25:c25:ffbb:d711/1282c19:dd:d9:dd:c25:c25:ffbb:d711
192c19:dd:d9:dd:c25:c25:ffbb:d712/1282c19:dd:d9:dd:c25:c25:ffbb:d712
202c19:dd:d9:dd:c25:c25:ffbb:d713/1282c19:dd:d9:dd:c25:c25:ffbb:d713
212c19:dd:d9:dd:c25:c25:ffbb:d714/1282c19:dd:d9:dd:c25:c25:ffbb:d714
222c19:dd:d9:dd:c25:c25:ffbb:d715/1282c19:dd:d9:dd:c25:c25:ffbb:d715
232c19:dd:d9:dd:c25:c25:ffbb:d716/1282c19:dd:d9:dd:c25:c25:ffbb:d716
242c19:dd:d9:dd:c25:c25:ffbb:d717/1282c19:dd:d9:dd:c25:c25:ffbb:d717
252c19:dd:d9:dd:c25:c25:ffbb:d718/1282c19:dd:d9:dd:c25:c25:ffbb:d718
262c19:dd:d9:dd:c25:c25:ffbb:d719/1282c19:dd:d9:dd:c25:c25:ffbb:d719
272c19:dd:d9:dd:c25:c25:ffbb:d71a/1282c19:dd:d9:dd:c25:c25:ffbb:d71a
282c19:dd:d9:dd:c25:c25:ffbb:d71b/1282c19:dd:d9:dd:c25:c25:ffbb:d71b
292c19:dd:d9:dd:c25:c25:ffbb:d71c/1282c19:dd:d9:dd:c25:c25:ffbb:d71c
302c19:dd:d9:dd:c25:c25:ffbb:d71d/1282c19:dd:d9:dd:c25:c25:ffbb:d71d
312c19:dd:d9:dd:c25:c25:ffbb:d71e/1282c19:dd:d9:dd:c25:c25:ffbb:d71e
322c19:dd:d9:dd:c25:c25:ffbb:d71f/1282c19:dd:d9:dd:c25:c25:ffbb:d71f
332c19:dd:d9:dd:c25:c25:ffbb:d720/1282c19:dd:d9:dd:c25:c25:ffbb:d720
342c19:dd:d9:dd:c25:c25:ffbb:d721/1282c19:dd:d9:dd:c25:c25:ffbb:d721
352c19:dd:d9:dd:c25:c25:ffbb:d722/1282c19:dd:d9:dd:c25:c25:ffbb:d722
362c19:dd:d9:dd:c25:c25:ffbb:d723/1282c19:dd:d9:dd:c25:c25:ffbb:d723
372c19:dd:d9:dd:c25:c25:ffbb:d724/1282c19:dd:d9:dd:c25:c25:ffbb:d724
382c19:dd:d9:dd:c25:c25:ffbb:d725/1282c19:dd:d9:dd:c25:c25:ffbb:d725
392c19:dd:d9:dd:c25:c25:ffbb:d726/1282c19:dd:d9:dd:c25:c25:ffbb:d726
402c19:dd:d9:dd:c25:c25:ffbb:d727/1282c19:dd:d9:dd:c25:c25:ffbb:d727
412c19:dd:d9:dd:c25:c25:ffbb:d728/1282c19:dd:d9:dd:c25:c25:ffbb:d728
422c19:dd:d9:dd:c25:c25:ffbb:d729/1282c19:dd:d9:dd:c25:c25:ffbb:d729
432c19:dd:d9:dd:c25:c25:ffbb:d72a/1282c19:dd:d9:dd:c25:c25:ffbb:d72a
442c19:dd:d9:dd:c25:c25:ffbb:d72b/1282c19:dd:d9:dd:c25:c25:ffbb:d72b
452c19:dd:d9:dd:c25:c25:ffbb:d72c/1282c19:dd:d9:dd:c25:c25:ffbb:d72c
462c19:dd:d9:dd:c25:c25:ffbb:d72d/1282c19:dd:d9:dd:c25:c25:ffbb:d72d
472c19:dd:d9:dd:c25:c25:ffbb:d72e/1282c19:dd:d9:dd:c25:c25:ffbb:d72e
482c19:dd:d9:dd:c25:c25:ffbb:d72f/1282c19:dd:d9:dd:c25:c25:ffbb:d72f
492c19:dd:d9:dd:c25:c25:ffbb:d730/1282c19:dd:d9:dd:c25:c25:ffbb:d730
502c19:dd:d9:dd:c25:c25:ffbb:d731/1282c19:dd:d9:dd:c25:c25:ffbb:d731
512c19:dd:d9:dd:c25:c25:ffbb:d732/1282c19:dd:d9:dd:c25:c25:ffbb:d732
522c19:dd:d9:dd:c25:c25:ffbb:d733/1282c19:dd:d9:dd:c25:c25:ffbb:d733
532c19:dd:d9:dd:c25:c25:ffbb:d734/1282c19:dd:d9:dd:c25:c25:ffbb:d734
542c19:dd:d9:dd:c25:c25:ffbb:d735/1282c19:dd:d9:dd:c25:c25:ffbb:d735
552c19:dd:d9:dd:c25:c25:ffbb:d736/1282c19:dd:d9:dd:c25:c25:ffbb:d736
562c19:dd:d9:dd:c25:c25:ffbb:d737/1282c19:dd:d9:dd:c25:c25:ffbb:d737
572c19:dd:d9:dd:c25:c25:ffbb:d738/1282c19:dd:d9:dd:c25:c25:ffbb:d738
582c19:dd:d9:dd:c25:c25:ffbb:d739/1282c19:dd:d9:dd:c25:c25:ffbb:d739
592c19:dd:d9:dd:c25:c25:ffbb:d73a/1282c19:dd:d9:dd:c25:c25:ffbb:d73a
602c19:dd:d9:dd:c25:c25:ffbb:d73b/1282c19:dd:d9:dd:c25:c25:ffbb:d73b
612c19:dd:d9:dd:c25:c25:ffbb:d73c/1282c19:dd:d9:dd:c25:c25:ffbb:d73c
622c19:dd:d9:dd:c25:c25:ffbb:d73d/1282c19:dd:d9:dd:c25:c25:ffbb:d73d
632c19:dd:d9:dd:c25:c25:ffbb:d73e/1282c19:dd:d9:dd:c25:c25:ffbb:d73e
642c19:dd:d9:dd:c25:c25:ffbb:d73f/1282c19:dd:d9:dd:c25:c25:ffbb:d73f
652c19:dd:d9:dd:c25:c25:ffbb:d740/1282c19:dd:d9:dd:c25:c25:ffbb:d740
662c19:dd:d9:dd:c25:c25:ffbb:d741/1282c19:dd:d9:dd:c25:c25:ffbb:d741
672c19:dd:d9:dd:c25:c25:ffbb:d742/1282c19:dd:d9:dd:c25:c25:ffbb:d742
682c19:dd:d9:dd:c25:c25:ffbb:d743/1282c19:dd:d9:dd:c25:c25:ffbb:d743
692c19:dd:d9:dd:c25:c25:ffbb:d744/1282c19:dd:d9:dd:c25:c25:ffbb:d744
702c19:dd:d9:dd:c25:c25:ffbb:d745/1282c19:dd:d9:dd:c25:c25:ffbb:d745
712c19:dd:d9:dd:c25:c25:ffbb:d746/1282c19:dd:d9:dd:c25:c25:ffbb:d746
722c19:dd:d9:dd:c25:c25:ffbb:d747/1282c19:dd:d9:dd:c25:c25:ffbb:d747
732c19:dd:d9:dd:c25:c25:ffbb:d748/1282c19:dd:d9:dd:c25:c25:ffbb:d748
742c19:dd:d9:dd:c25:c25:ffbb:d749/1282c19:dd:d9:dd:c25:c25:ffbb:d749
752c19:dd:d9:dd:c25:c25:ffbb:d74a/1282c19:dd:d9:dd:c25:c25:ffbb:d74a
762c19:dd:d9:dd:c25:c25:ffbb:d74b/1282c19:dd:d9:dd:c25:c25:ffbb:d74b
772c19:dd:d9:dd:c25:c25:ffbb:d74c/1282c19:dd:d9:dd:c25:c25:ffbb:d74c
782c19:dd:d9:dd:c25:c25:ffbb:d74d/1282c19:dd:d9:dd:c25:c25:ffbb:d74d
792c19:dd:d9:dd:c25:c25:ffbb:d74e/1282c19:dd:d9:dd:c25:c25:ffbb:d74e
802c19:dd:d9:dd:c25:c25:ffbb:d74f/1282c19:dd:d9:dd:c25:c25:ffbb:d74f
812c19:dd:d9:dd:c25:c25:ffbb:d750/1282c19:dd:d9:dd:c25:c25:ffbb:d750
822c19:dd:d9:dd:c25:c25:ffbb:d751/1282c19:dd:d9:dd:c25:c25:ffbb:d751
832c19:dd:d9:dd:c25:c25:ffbb:d752/1282c19:dd:d9:dd:c25:c25:ffbb:d752
842c19:dd:d9:dd:c25:c25:ffbb:d753/1282c19:dd:d9:dd:c25:c25:ffbb:d753
852c19:dd:d9:dd:c25:c25:ffbb:d754/1282c19:dd:d9:dd:c25:c25:ffbb:d754
862c19:dd:d9:dd:c25:c25:ffbb:d755/1282c19:dd:d9:dd:c25:c25:ffbb:d755
872c19:dd:d9:dd:c25:c25:ffbb:d756/1282c19:dd:d9:dd:c25:c25:ffbb:d756
882c19:dd:d9:dd:c25:c25:ffbb:d757/1282c19:dd:d9:dd:c25:c25:ffbb:d757
892c19:dd:d9:dd:c25:c25:ffbb:d758/1282c19:dd:d9:dd:c25:c25:ffbb:d758
902c19:dd:d9:dd:c25:c25:ffbb:d759/1282c19:dd:d9:dd:c25:c25:ffbb:d759
912c19:dd:d9:dd:c25:c25:ffbb:d75a/1282c19:dd:d9:dd:c25:c25:ffbb:d75a
922c19:dd:d9:dd:c25:c25:ffbb:d75b/1282c19:dd:d9:dd:c25:c25:ffbb:d75b
932c19:dd:d9:dd:c25:c25:ffbb:d75c/1282c19:dd:d9:dd:c25:c25:ffbb:d75c
942c19:dd:d9:dd:c25:c25:ffbb:d75d/1282c19:dd:d9:dd:c25:c25:ffbb:d75d
952c19:dd:d9:dd:c25:c25:ffbb:d75e/1282c19:dd:d9:dd:c25:c25:ffbb:d75e
962c19:dd:d9:dd:c25:c25:ffbb:d75f/1282c19:dd:d9:dd:c25:c25:ffbb:d75f
972c19:dd:d9:dd:c25:c25:ffbb:d760/1282c19:dd:d9:dd:c25:c25:ffbb:d760
982c19:dd:d9:dd:c25:c25:ffbb:d761/1282c19:dd:d9:dd:c25:c25:ffbb:d761
992c19:dd:d9:dd:c25:c25:ffbb:d762/1282c19:dd:d9:dd:c25:c25:ffbb:d762
1002c19:dd:d9:dd:c25:c25:ffbb:d763/1282c19:dd:d9:dd:c25:c25:ffbb:d763
1012c19:dd:d9:dd:c25:c25:ffbb:d764/1282c19:dd:d9:dd:c25:c25:ffbb:d764
1022c19:dd:d9:dd:c25:c25:ffbb:d765/1282c19:dd:d9:dd:c25:c25:ffbb:d765
1032c19:dd:d9:dd:c25:c25:ffbb:d766/1282c19:dd:d9:dd:c25:c25:ffbb:d766
1042c19:dd:d9:dd:c25:c25:ffbb:d767/1282c19:dd:d9:dd:c25:c25:ffbb:d767
1052c19:dd:d9:dd:c25:c25:ffbb:d768/1282c19:dd:d9:dd:c25:c25:ffbb:d768
1062c19:dd:d9:dd:c25:c25:ffbb:d769/1282c19:dd:d9:dd:c25:c25:ffbb:d769
1072c19:dd:d9:dd:c25:c25:ffbb:d76a/1282c19:dd:d9:dd:c25:c25:ffbb:d76a
1082c19:dd:d9:dd:c25:c25:ffbb:d76b/1282c19:dd:d9:dd:c25:c25:ffbb:d76b
1092c19:dd:d9:dd:c25:c25:ffbb:d76c/1282c19:dd:d9:dd:c25:c25:ffbb:d76c
1102c19:dd:d9:dd:c25:c25:ffbb:d76d/1282c19:dd:d9:dd:c25:c25:ffbb:d76d
1112c19:dd:d9:dd:c25:c25:ffbb:d76e/1282c19:dd:d9:dd:c25:c25:ffbb:d76e
1122c19:dd:d9:dd:c25:c25:ffbb:d76f/1282c19:dd:d9:dd:c25:c25:ffbb:d76f
1132c19:dd:d9:dd:c25:c25:ffbb:d770/1282c19:dd:d9:dd:c25:c25:ffbb:d770
1142c19:dd:d9:dd:c25:c25:ffbb:d771/1282c19:dd:d9:dd:c25:c25:ffbb:d771
1152c19:dd:d9:dd:c25:c25:ffbb:d772/1282c19:dd:d9:dd:c25:c25:ffbb:d772
1162c19:dd:d9:dd:c25:c25:ffbb:d773/1282c19:dd:d9:dd:c25:c25:ffbb:d773
1172c19:dd:d9:dd:c25:c25:ffbb:d774/1282c19:dd:d9:dd:c25:c25:ffbb:d774
1182c19:dd:d9:dd:c25:c25:ffbb:d775/1282c19:dd:d9:dd:c25:c25:ffbb:d775
1192c19:dd:d9:dd:c25:c25:ffbb:d776/1282c19:dd:d9:dd:c25:c25:ffbb:d776
1202c19:dd:d9:dd:c25:c25:ffbb:d777/1282c19:dd:d9:dd:c25:c25:ffbb:d777
1212c19:dd:d9:dd:c25:c25:ffbb:d778/1282c19:dd:d9:dd:c25:c25:ffbb:d778
1222c19:dd:d9:dd:c25:c25:ffbb:d779/1282c19:dd:d9:dd:c25:c25:ffbb:d779
1232c19:dd:d9:dd:c25:c25:ffbb:d77a/1282c19:dd:d9:dd:c25:c25:ffbb:d77a
1242c19:dd:d9:dd:c25:c25:ffbb:d77b/1282c19:dd:d9:dd:c25:c25:ffbb:d77b
1252c19:dd:d9:dd:c25:c25:ffbb:d77c/1282c19:dd:d9:dd:c25:c25:ffbb:d77c
1262c19:dd:d9:dd:c25:c25:ffbb:d77d/1282c19:dd:d9:dd:c25:c25:ffbb:d77d
1272c19:dd:d9:dd:c25:c25:ffbb:d77e/1282c19:dd:d9:dd:c25:c25:ffbb:d77e
1282c19:dd:d9:dd:c25:c25:ffbb:d77f/1282c19:dd:d9:dd:c25:c25:ffbb:d77f
1292c19:dd:d9:dd:c25:c25:ffbb:d780/1282c19:dd:d9:dd:c25:c25:ffbb:d780
1302c19:dd:d9:dd:c25:c25:ffbb:d781/1282c19:dd:d9:dd:c25:c25:ffbb:d781
1312c19:dd:d9:dd:c25:c25:ffbb:d782/1282c19:dd:d9:dd:c25:c25:ffbb:d782
1322c19:dd:d9:dd:c25:c25:ffbb:d783/1282c19:dd:d9:dd:c25:c25:ffbb:d783
1332c19:dd:d9:dd:c25:c25:ffbb:d784/1282c19:dd:d9:dd:c25:c25:ffbb:d784
1342c19:dd:d9:dd:c25:c25:ffbb:d785/1282c19:dd:d9:dd:c25:c25:ffbb:d785
1352c19:dd:d9:dd:c25:c25:ffbb:d786/1282c19:dd:d9:dd:c25:c25:ffbb:d786
1362c19:dd:d9:dd:c25:c25:ffbb:d787/1282c19:dd:d9:dd:c25:c25:ffbb:d787
1372c19:dd:d9:dd:c25:c25:ffbb:d788/1282c19:dd:d9:dd:c25:c25:ffbb:d788
1382c19:dd:d9:dd:c25:c25:ffbb:d789/1282c19:dd:d9:dd:c25:c25:ffbb:d789
1392c19:dd:d9:dd:c25:c25:ffbb:d78a/1282c19:dd:d9:dd:c25:c25:ffbb:d78a
1402c19:dd:d9:dd:c25:c25:ffbb:d78b/1282c19:dd:d9:dd:c25:c25:ffbb:d78b
1412c19:dd:d9:dd:c25:c25:ffbb:d78c/1282c19:dd:d9:dd:c25:c25:ffbb:d78c
1422c19:dd:d9:dd:c25:c25:ffbb:d78d/1282c19:dd:d9:dd:c25:c25:ffbb:d78d
1432c19:dd:d9:dd:c25:c25:ffbb:d78e/1282c19:dd:d9:dd:c25:c25:ffbb:d78e
1442c19:dd:d9:dd:c25:c25:ffbb:d78f/1282c19:dd:d9:dd:c25:c25:ffbb:d78f
1452c19:dd:d9:dd:c25:c25:ffbb:d790/1282c19:dd:d9:dd:c25:c25:ffbb:d790
1462c19:dd:d9:dd:c25:c25:ffbb:d791/1282c19:dd:d9:dd:c25:c25:ffbb:d791
1472c19:dd:d9:dd:c25:c25:ffbb:d792/1282c19:dd:d9:dd:c25:c25:ffbb:d792
1482c19:dd:d9:dd:c25:c25:ffbb:d793/1282c19:dd:d9:dd:c25:c25:ffbb:d793
1492c19:dd:d9:dd:c25:c25:ffbb:d794/1282c19:dd:d9:dd:c25:c25:ffbb:d794
1502c19:dd:d9:dd:c25:c25:ffbb:d795/1282c19:dd:d9:dd:c25:c25:ffbb:d795
1512c19:dd:d9:dd:c25:c25:ffbb:d796/1282c19:dd:d9:dd:c25:c25:ffbb:d796
1522c19:dd:d9:dd:c25:c25:ffbb:d797/1282c19:dd:d9:dd:c25:c25:ffbb:d797
1532c19:dd:d9:dd:c25:c25:ffbb:d798/1282c19:dd:d9:dd:c25:c25:ffbb:d798
1542c19:dd:d9:dd:c25:c25:ffbb:d799/1282c19:dd:d9:dd:c25:c25:ffbb:d799
1552c19:dd:d9:dd:c25:c25:ffbb:d79a/1282c19:dd:d9:dd:c25:c25:ffbb:d79a
1562c19:dd:d9:dd:c25:c25:ffbb:d79b/1282c19:dd:d9:dd:c25:c25:ffbb:d79b
1572c19:dd:d9:dd:c25:c25:ffbb:d79c/1282c19:dd:d9:dd:c25:c25:ffbb:d79c
1582c19:dd:d9:dd:c25:c25:ffbb:d79d/1282c19:dd:d9:dd:c25:c25:ffbb:d79d
1592c19:dd:d9:dd:c25:c25:ffbb:d79e/1282c19:dd:d9:dd:c25:c25:ffbb:d79e
1602c19:dd:d9:dd:c25:c25:ffbb:d79f/1282c19:dd:d9:dd:c25:c25:ffbb:d79f
1612c19:dd:d9:dd:c25:c25:ffbb:d7a0/1282c19:dd:d9:dd:c25:c25:ffbb:d7a0
1622c19:dd:d9:dd:c25:c25:ffbb:d7a1/1282c19:dd:d9:dd:c25:c25:ffbb:d7a1
1632c19:dd:d9:dd:c25:c25:ffbb:d7a2/1282c19:dd:d9:dd:c25:c25:ffbb:d7a2
1642c19:dd:d9:dd:c25:c25:ffbb:d7a3/1282c19:dd:d9:dd:c25:c25:ffbb:d7a3
1652c19:dd:d9:dd:c25:c25:ffbb:d7a4/1282c19:dd:d9:dd:c25:c25:ffbb:d7a4
1662c19:dd:d9:dd:c25:c25:ffbb:d7a5/1282c19:dd:d9:dd:c25:c25:ffbb:d7a5
1672c19:dd:d9:dd:c25:c25:ffbb:d7a6/1282c19:dd:d9:dd:c25:c25:ffbb:d7a6
1682c19:dd:d9:dd:c25:c25:ffbb:d7a7/1282c19:dd:d9:dd:c25:c25:ffbb:d7a7
1692c19:dd:d9:dd:c25:c25:ffbb:d7a8/1282c19:dd:d9:dd:c25:c25:ffbb:d7a8
1702c19:dd:d9:dd:c25:c25:ffbb:d7a9/1282c19:dd:d9:dd:c25:c25:ffbb:d7a9
1712c19:dd:d9:dd:c25:c25:ffbb:d7aa/1282c19:dd:d9:dd:c25:c25:ffbb:d7aa
1722c19:dd:d9:dd:c25:c25:ffbb:d7ab/1282c19:dd:d9:dd:c25:c25:ffbb:d7ab
1732c19:dd:d9:dd:c25:c25:ffbb:d7ac/1282c19:dd:d9:dd:c25:c25:ffbb:d7ac
1742c19:dd:d9:dd:c25:c25:ffbb:d7ad/1282c19:dd:d9:dd:c25:c25:ffbb:d7ad
1752c19:dd:d9:dd:c25:c25:ffbb:d7ae/1282c19:dd:d9:dd:c25:c25:ffbb:d7ae
1762c19:dd:d9:dd:c25:c25:ffbb:d7af/1282c19:dd:d9:dd:c25:c25:ffbb:d7af
1772c19:dd:d9:dd:c25:c25:ffbb:d7b0/1282c19:dd:d9:dd:c25:c25:ffbb:d7b0
1782c19:dd:d9:dd:c25:c25:ffbb:d7b1/1282c19:dd:d9:dd:c25:c25:ffbb:d7b1
1792c19:dd:d9:dd:c25:c25:ffbb:d7b2/1282c19:dd:d9:dd:c25:c25:ffbb:d7b2
1802c19:dd:d9:dd:c25:c25:ffbb:d7b3/1282c19:dd:d9:dd:c25:c25:ffbb:d7b3
1812c19:dd:d9:dd:c25:c25:ffbb:d7b4/1282c19:dd:d9:dd:c25:c25:ffbb:d7b4
1822c19:dd:d9:dd:c25:c25:ffbb:d7b5/1282c19:dd:d9:dd:c25:c25:ffbb:d7b5
1832c19:dd:d9:dd:c25:c25:ffbb:d7b6/1282c19:dd:d9:dd:c25:c25:ffbb:d7b6
1842c19:dd:d9:dd:c25:c25:ffbb:d7b7/1282c19:dd:d9:dd:c25:c25:ffbb:d7b7
1852c19:dd:d9:dd:c25:c25:ffbb:d7b8/1282c19:dd:d9:dd:c25:c25:ffbb:d7b8
1862c19:dd:d9:dd:c25:c25:ffbb:d7b9/1282c19:dd:d9:dd:c25:c25:ffbb:d7b9
1872c19:dd:d9:dd:c25:c25:ffbb:d7ba/1282c19:dd:d9:dd:c25:c25:ffbb:d7ba
1882c19:dd:d9:dd:c25:c25:ffbb:d7bb/1282c19:dd:d9:dd:c25:c25:ffbb:d7bb
1892c19:dd:d9:dd:c25:c25:ffbb:d7bc/1282c19:dd:d9:dd:c25:c25:ffbb:d7bc
1902c19:dd:d9:dd:c25:c25:ffbb:d7bd/1282c19:dd:d9:dd:c25:c25:ffbb:d7bd
1912c19:dd:d9:dd:c25:c25:ffbb:d7be/1282c19:dd:d9:dd:c25:c25:ffbb:d7be
1922c19:dd:d9:dd:c25:c25:ffbb:d7bf/1282c19:dd:d9:dd:c25:c25:ffbb:d7bf
1932c19:dd:d9:dd:c25:c25:ffbb:d7c0/1282c19:dd:d9:dd:c25:c25:ffbb:d7c0
1942c19:dd:d9:dd:c25:c25:ffbb:d7c1/1282c19:dd:d9:dd:c25:c25:ffbb:d7c1
1952c19:dd:d9:dd:c25:c25:ffbb:d7c2/1282c19:dd:d9:dd:c25:c25:ffbb:d7c2
1962c19:dd:d9:dd:c25:c25:ffbb:d7c3/1282c19:dd:d9:dd:c25:c25:ffbb:d7c3
1972c19:dd:d9:dd:c25:c25:ffbb:d7c4/1282c19:dd:d9:dd:c25:c25:ffbb:d7c4
1982c19:dd:d9:dd:c25:c25:ffbb:d7c5/1282c19:dd:d9:dd:c25:c25:ffbb:d7c5
1992c19:dd:d9:dd:c25:c25:ffbb:d7c6/1282c19:dd:d9:dd:c25:c25:ffbb:d7c6
2002c19:dd:d9:dd:c25:c25:ffbb:d7c7/1282c19:dd:d9:dd:c25:c25:ffbb:d7c7
2012c19:dd:d9:dd:c25:c25:ffbb:d7c8/1282c19:dd:d9:dd:c25:c25:ffbb:d7c8
2022c19:dd:d9:dd:c25:c25:ffbb:d7c9/1282c19:dd:d9:dd:c25:c25:ffbb:d7c9
2032c19:dd:d9:dd:c25:c25:ffbb:d7ca/1282c19:dd:d9:dd:c25:c25:ffbb:d7ca
2042c19:dd:d9:dd:c25:c25:ffbb:d7cb/1282c19:dd:d9:dd:c25:c25:ffbb:d7cb
2052c19:dd:d9:dd:c25:c25:ffbb:d7cc/1282c19:dd:d9:dd:c25:c25:ffbb:d7cc
2062c19:dd:d9:dd:c25:c25:ffbb:d7cd/1282c19:dd:d9:dd:c25:c25:ffbb:d7cd
2072c19:dd:d9:dd:c25:c25:ffbb:d7ce/1282c19:dd:d9:dd:c25:c25:ffbb:d7ce
2082c19:dd:d9:dd:c25:c25:ffbb:d7cf/1282c19:dd:d9:dd:c25:c25:ffbb:d7cf
2092c19:dd:d9:dd:c25:c25:ffbb:d7d0/1282c19:dd:d9:dd:c25:c25:ffbb:d7d0
2102c19:dd:d9:dd:c25:c25:ffbb:d7d1/1282c19:dd:d9:dd:c25:c25:ffbb:d7d1
2112c19:dd:d9:dd:c25:c25:ffbb:d7d2/1282c19:dd:d9:dd:c25:c25:ffbb:d7d2
2122c19:dd:d9:dd:c25:c25:ffbb:d7d3/1282c19:dd:d9:dd:c25:c25:ffbb:d7d3
2132c19:dd:d9:dd:c25:c25:ffbb:d7d4/1282c19:dd:d9:dd:c25:c25:ffbb:d7d4
2142c19:dd:d9:dd:c25:c25:ffbb:d7d5/1282c19:dd:d9:dd:c25:c25:ffbb:d7d5
2152c19:dd:d9:dd:c25:c25:ffbb:d7d6/1282c19:dd:d9:dd:c25:c25:ffbb:d7d6
2162c19:dd:d9:dd:c25:c25:ffbb:d7d7/1282c19:dd:d9:dd:c25:c25:ffbb:d7d7
2172c19:dd:d9:dd:c25:c25:ffbb:d7d8/1282c19:dd:d9:dd:c25:c25:ffbb:d7d8
2182c19:dd:d9:dd:c25:c25:ffbb:d7d9/1282c19:dd:d9:dd:c25:c25:ffbb:d7d9
2192c19:dd:d9:dd:c25:c25:ffbb:d7da/1282c19:dd:d9:dd:c25:c25:ffbb:d7da
2202c19:dd:d9:dd:c25:c25:ffbb:d7db/1282c19:dd:d9:dd:c25:c25:ffbb:d7db
2212c19:dd:d9:dd:c25:c25:ffbb:d7dc/1282c19:dd:d9:dd:c25:c25:ffbb:d7dc
2222c19:dd:d9:dd:c25:c25:ffbb:d7dd/1282c19:dd:d9:dd:c25:c25:ffbb:d7dd
2232c19:dd:d9:dd:c25:c25:ffbb:d7de/1282c19:dd:d9:dd:c25:c25:ffbb:d7de
2242c19:dd:d9:dd:c25:c25:ffbb:d7df/1282c19:dd:d9:dd:c25:c25:ffbb:d7df
2252c19:dd:d9:dd:c25:c25:ffbb:d7e0/1282c19:dd:d9:dd:c25:c25:ffbb:d7e0
2262c19:dd:d9:dd:c25:c25:ffbb:d7e1/1282c19:dd:d9:dd:c25:c25:ffbb:d7e1
2272c19:dd:d9:dd:c25:c25:ffbb:d7e2/1282c19:dd:d9:dd:c25:c25:ffbb:d7e2
2282c19:dd:d9:dd:c25:c25:ffbb:d7e3/1282c19:dd:d9:dd:c25:c25:ffbb:d7e3
2292c19:dd:d9:dd:c25:c25:ffbb:d7e4/1282c19:dd:d9:dd:c25:c25:ffbb:d7e4
2302c19:dd:d9:dd:c25:c25:ffbb:d7e5/1282c19:dd:d9:dd:c25:c25:ffbb:d7e5
2312c19:dd:d9:dd:c25:c25:ffbb:d7e6/1282c19:dd:d9:dd:c25:c25:ffbb:d7e6
2322c19:dd:d9:dd:c25:c25:ffbb:d7e7/1282c19:dd:d9:dd:c25:c25:ffbb:d7e7
2332c19:dd:d9:dd:c25:c25:ffbb:d7e8/1282c19:dd:d9:dd:c25:c25:ffbb:d7e8
2342c19:dd:d9:dd:c25:c25:ffbb:d7e9/1282c19:dd:d9:dd:c25:c25:ffbb:d7e9
2352c19:dd:d9:dd:c25:c25:ffbb:d7ea/1282c19:dd:d9:dd:c25:c25:ffbb:d7ea
2362c19:dd:d9:dd:c25:c25:ffbb:d7eb/1282c19:dd:d9:dd:c25:c25:ffbb:d7eb
2372c19:dd:d9:dd:c25:c25:ffbb:d7ec/1282c19:dd:d9:dd:c25:c25:ffbb:d7ec
2382c19:dd:d9:dd:c25:c25:ffbb:d7ed/1282c19:dd:d9:dd:c25:c25:ffbb:d7ed
2392c19:dd:d9:dd:c25:c25:ffbb:d7ee/1282c19:dd:d9:dd:c25:c25:ffbb:d7ee
2402c19:dd:d9:dd:c25:c25:ffbb:d7ef/1282c19:dd:d9:dd:c25:c25:ffbb:d7ef
2412c19:dd:d9:dd:c25:c25:ffbb:d7f0/1282c19:dd:d9:dd:c25:c25:ffbb:d7f0
2422c19:dd:d9:dd:c25:c25:ffbb:d7f1/1282c19:dd:d9:dd:c25:c25:ffbb:d7f1
2432c19:dd:d9:dd:c25:c25:ffbb:d7f2/1282c19:dd:d9:dd:c25:c25:ffbb:d7f2
2442c19:dd:d9:dd:c25:c25:ffbb:d7f3/1282c19:dd:d9:dd:c25:c25:ffbb:d7f3
2452c19:dd:d9:dd:c25:c25:ffbb:d7f4/1282c19:dd:d9:dd:c25:c25:ffbb:d7f4
2462c19:dd:d9:dd:c25:c25:ffbb:d7f5/1282c19:dd:d9:dd:c25:c25:ffbb:d7f5
2472c19:dd:d9:dd:c25:c25:ffbb:d7f6/1282c19:dd:d9:dd:c25:c25:ffbb:d7f6
2482c19:dd:d9:dd:c25:c25:ffbb:d7f7/1282c19:dd:d9:dd:c25:c25:ffbb:d7f7
2492c19:dd:d9:dd:c25:c25:ffbb:d7f8/1282c19:dd:d9:dd:c25:c25:ffbb:d7f8
2502c19:dd:d9:dd:c25:c25:ffbb:d7f9/1282c19:dd:d9:dd:c25:c25:ffbb:d7f9
2512c19:dd:d9:dd:c25:c25:ffbb:d7fa/1282c19:dd:d9:dd:c25:c25:ffbb:d7fa
2522c19:dd:d9:dd:c25:c25:ffbb:d7fb/1282c19:dd:d9:dd:c25:c25:ffbb:d7fb
2532c19:dd:d9:dd:c25:c25:ffbb:d7fc/1282c19:dd:d9:dd:c25:c25:ffbb:d7fc
2542c19:dd:d9:dd:c25:c25:ffbb:d7fd/1282c19:dd:d9:dd:c25:c25:ffbb:d7fd
2552c19:dd:d9:dd:c25:c25:ffbb:d7fe/1282c19:dd:d9:dd:c25:c25:ffbb:d7fe
2562c19:dd:d9:dd:c25:c25:ffbb:d7ff/1282c19:dd:d9:dd:c25:c25:ffbb:d7ff

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.