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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:c25a:d00a:e700/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:e700
Last address
2c19:dd:d9:dd:c25:c25a:d00a:e7ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:e700
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
7.e.a.0.0.d.a.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:c25a:d00a:e700/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:e700/1282c19:dd:d9:dd:c25:c25a:d00a:e700
22c19:dd:d9:dd:c25:c25a:d00a:e701/1282c19:dd:d9:dd:c25:c25a:d00a:e701
32c19:dd:d9:dd:c25:c25a:d00a:e702/1282c19:dd:d9:dd:c25:c25a:d00a:e702
42c19:dd:d9:dd:c25:c25a:d00a:e703/1282c19:dd:d9:dd:c25:c25a:d00a:e703
52c19:dd:d9:dd:c25:c25a:d00a:e704/1282c19:dd:d9:dd:c25:c25a:d00a:e704
62c19:dd:d9:dd:c25:c25a:d00a:e705/1282c19:dd:d9:dd:c25:c25a:d00a:e705
72c19:dd:d9:dd:c25:c25a:d00a:e706/1282c19:dd:d9:dd:c25:c25a:d00a:e706
82c19:dd:d9:dd:c25:c25a:d00a:e707/1282c19:dd:d9:dd:c25:c25a:d00a:e707
92c19:dd:d9:dd:c25:c25a:d00a:e708/1282c19:dd:d9:dd:c25:c25a:d00a:e708
102c19:dd:d9:dd:c25:c25a:d00a:e709/1282c19:dd:d9:dd:c25:c25a:d00a:e709
112c19:dd:d9:dd:c25:c25a:d00a:e70a/1282c19:dd:d9:dd:c25:c25a:d00a:e70a
122c19:dd:d9:dd:c25:c25a:d00a:e70b/1282c19:dd:d9:dd:c25:c25a:d00a:e70b
132c19:dd:d9:dd:c25:c25a:d00a:e70c/1282c19:dd:d9:dd:c25:c25a:d00a:e70c
142c19:dd:d9:dd:c25:c25a:d00a:e70d/1282c19:dd:d9:dd:c25:c25a:d00a:e70d
152c19:dd:d9:dd:c25:c25a:d00a:e70e/1282c19:dd:d9:dd:c25:c25a:d00a:e70e
162c19:dd:d9:dd:c25:c25a:d00a:e70f/1282c19:dd:d9:dd:c25:c25a:d00a:e70f
172c19:dd:d9:dd:c25:c25a:d00a:e710/1282c19:dd:d9:dd:c25:c25a:d00a:e710
182c19:dd:d9:dd:c25:c25a:d00a:e711/1282c19:dd:d9:dd:c25:c25a:d00a:e711
192c19:dd:d9:dd:c25:c25a:d00a:e712/1282c19:dd:d9:dd:c25:c25a:d00a:e712
202c19:dd:d9:dd:c25:c25a:d00a:e713/1282c19:dd:d9:dd:c25:c25a:d00a:e713
212c19:dd:d9:dd:c25:c25a:d00a:e714/1282c19:dd:d9:dd:c25:c25a:d00a:e714
222c19:dd:d9:dd:c25:c25a:d00a:e715/1282c19:dd:d9:dd:c25:c25a:d00a:e715
232c19:dd:d9:dd:c25:c25a:d00a:e716/1282c19:dd:d9:dd:c25:c25a:d00a:e716
242c19:dd:d9:dd:c25:c25a:d00a:e717/1282c19:dd:d9:dd:c25:c25a:d00a:e717
252c19:dd:d9:dd:c25:c25a:d00a:e718/1282c19:dd:d9:dd:c25:c25a:d00a:e718
262c19:dd:d9:dd:c25:c25a:d00a:e719/1282c19:dd:d9:dd:c25:c25a:d00a:e719
272c19:dd:d9:dd:c25:c25a:d00a:e71a/1282c19:dd:d9:dd:c25:c25a:d00a:e71a
282c19:dd:d9:dd:c25:c25a:d00a:e71b/1282c19:dd:d9:dd:c25:c25a:d00a:e71b
292c19:dd:d9:dd:c25:c25a:d00a:e71c/1282c19:dd:d9:dd:c25:c25a:d00a:e71c
302c19:dd:d9:dd:c25:c25a:d00a:e71d/1282c19:dd:d9:dd:c25:c25a:d00a:e71d
312c19:dd:d9:dd:c25:c25a:d00a:e71e/1282c19:dd:d9:dd:c25:c25a:d00a:e71e
322c19:dd:d9:dd:c25:c25a:d00a:e71f/1282c19:dd:d9:dd:c25:c25a:d00a:e71f
332c19:dd:d9:dd:c25:c25a:d00a:e720/1282c19:dd:d9:dd:c25:c25a:d00a:e720
342c19:dd:d9:dd:c25:c25a:d00a:e721/1282c19:dd:d9:dd:c25:c25a:d00a:e721
352c19:dd:d9:dd:c25:c25a:d00a:e722/1282c19:dd:d9:dd:c25:c25a:d00a:e722
362c19:dd:d9:dd:c25:c25a:d00a:e723/1282c19:dd:d9:dd:c25:c25a:d00a:e723
372c19:dd:d9:dd:c25:c25a:d00a:e724/1282c19:dd:d9:dd:c25:c25a:d00a:e724
382c19:dd:d9:dd:c25:c25a:d00a:e725/1282c19:dd:d9:dd:c25:c25a:d00a:e725
392c19:dd:d9:dd:c25:c25a:d00a:e726/1282c19:dd:d9:dd:c25:c25a:d00a:e726
402c19:dd:d9:dd:c25:c25a:d00a:e727/1282c19:dd:d9:dd:c25:c25a:d00a:e727
412c19:dd:d9:dd:c25:c25a:d00a:e728/1282c19:dd:d9:dd:c25:c25a:d00a:e728
422c19:dd:d9:dd:c25:c25a:d00a:e729/1282c19:dd:d9:dd:c25:c25a:d00a:e729
432c19:dd:d9:dd:c25:c25a:d00a:e72a/1282c19:dd:d9:dd:c25:c25a:d00a:e72a
442c19:dd:d9:dd:c25:c25a:d00a:e72b/1282c19:dd:d9:dd:c25:c25a:d00a:e72b
452c19:dd:d9:dd:c25:c25a:d00a:e72c/1282c19:dd:d9:dd:c25:c25a:d00a:e72c
462c19:dd:d9:dd:c25:c25a:d00a:e72d/1282c19:dd:d9:dd:c25:c25a:d00a:e72d
472c19:dd:d9:dd:c25:c25a:d00a:e72e/1282c19:dd:d9:dd:c25:c25a:d00a:e72e
482c19:dd:d9:dd:c25:c25a:d00a:e72f/1282c19:dd:d9:dd:c25:c25a:d00a:e72f
492c19:dd:d9:dd:c25:c25a:d00a:e730/1282c19:dd:d9:dd:c25:c25a:d00a:e730
502c19:dd:d9:dd:c25:c25a:d00a:e731/1282c19:dd:d9:dd:c25:c25a:d00a:e731
512c19:dd:d9:dd:c25:c25a:d00a:e732/1282c19:dd:d9:dd:c25:c25a:d00a:e732
522c19:dd:d9:dd:c25:c25a:d00a:e733/1282c19:dd:d9:dd:c25:c25a:d00a:e733
532c19:dd:d9:dd:c25:c25a:d00a:e734/1282c19:dd:d9:dd:c25:c25a:d00a:e734
542c19:dd:d9:dd:c25:c25a:d00a:e735/1282c19:dd:d9:dd:c25:c25a:d00a:e735
552c19:dd:d9:dd:c25:c25a:d00a:e736/1282c19:dd:d9:dd:c25:c25a:d00a:e736
562c19:dd:d9:dd:c25:c25a:d00a:e737/1282c19:dd:d9:dd:c25:c25a:d00a:e737
572c19:dd:d9:dd:c25:c25a:d00a:e738/1282c19:dd:d9:dd:c25:c25a:d00a:e738
582c19:dd:d9:dd:c25:c25a:d00a:e739/1282c19:dd:d9:dd:c25:c25a:d00a:e739
592c19:dd:d9:dd:c25:c25a:d00a:e73a/1282c19:dd:d9:dd:c25:c25a:d00a:e73a
602c19:dd:d9:dd:c25:c25a:d00a:e73b/1282c19:dd:d9:dd:c25:c25a:d00a:e73b
612c19:dd:d9:dd:c25:c25a:d00a:e73c/1282c19:dd:d9:dd:c25:c25a:d00a:e73c
622c19:dd:d9:dd:c25:c25a:d00a:e73d/1282c19:dd:d9:dd:c25:c25a:d00a:e73d
632c19:dd:d9:dd:c25:c25a:d00a:e73e/1282c19:dd:d9:dd:c25:c25a:d00a:e73e
642c19:dd:d9:dd:c25:c25a:d00a:e73f/1282c19:dd:d9:dd:c25:c25a:d00a:e73f
652c19:dd:d9:dd:c25:c25a:d00a:e740/1282c19:dd:d9:dd:c25:c25a:d00a:e740
662c19:dd:d9:dd:c25:c25a:d00a:e741/1282c19:dd:d9:dd:c25:c25a:d00a:e741
672c19:dd:d9:dd:c25:c25a:d00a:e742/1282c19:dd:d9:dd:c25:c25a:d00a:e742
682c19:dd:d9:dd:c25:c25a:d00a:e743/1282c19:dd:d9:dd:c25:c25a:d00a:e743
692c19:dd:d9:dd:c25:c25a:d00a:e744/1282c19:dd:d9:dd:c25:c25a:d00a:e744
702c19:dd:d9:dd:c25:c25a:d00a:e745/1282c19:dd:d9:dd:c25:c25a:d00a:e745
712c19:dd:d9:dd:c25:c25a:d00a:e746/1282c19:dd:d9:dd:c25:c25a:d00a:e746
722c19:dd:d9:dd:c25:c25a:d00a:e747/1282c19:dd:d9:dd:c25:c25a:d00a:e747
732c19:dd:d9:dd:c25:c25a:d00a:e748/1282c19:dd:d9:dd:c25:c25a:d00a:e748
742c19:dd:d9:dd:c25:c25a:d00a:e749/1282c19:dd:d9:dd:c25:c25a:d00a:e749
752c19:dd:d9:dd:c25:c25a:d00a:e74a/1282c19:dd:d9:dd:c25:c25a:d00a:e74a
762c19:dd:d9:dd:c25:c25a:d00a:e74b/1282c19:dd:d9:dd:c25:c25a:d00a:e74b
772c19:dd:d9:dd:c25:c25a:d00a:e74c/1282c19:dd:d9:dd:c25:c25a:d00a:e74c
782c19:dd:d9:dd:c25:c25a:d00a:e74d/1282c19:dd:d9:dd:c25:c25a:d00a:e74d
792c19:dd:d9:dd:c25:c25a:d00a:e74e/1282c19:dd:d9:dd:c25:c25a:d00a:e74e
802c19:dd:d9:dd:c25:c25a:d00a:e74f/1282c19:dd:d9:dd:c25:c25a:d00a:e74f
812c19:dd:d9:dd:c25:c25a:d00a:e750/1282c19:dd:d9:dd:c25:c25a:d00a:e750
822c19:dd:d9:dd:c25:c25a:d00a:e751/1282c19:dd:d9:dd:c25:c25a:d00a:e751
832c19:dd:d9:dd:c25:c25a:d00a:e752/1282c19:dd:d9:dd:c25:c25a:d00a:e752
842c19:dd:d9:dd:c25:c25a:d00a:e753/1282c19:dd:d9:dd:c25:c25a:d00a:e753
852c19:dd:d9:dd:c25:c25a:d00a:e754/1282c19:dd:d9:dd:c25:c25a:d00a:e754
862c19:dd:d9:dd:c25:c25a:d00a:e755/1282c19:dd:d9:dd:c25:c25a:d00a:e755
872c19:dd:d9:dd:c25:c25a:d00a:e756/1282c19:dd:d9:dd:c25:c25a:d00a:e756
882c19:dd:d9:dd:c25:c25a:d00a:e757/1282c19:dd:d9:dd:c25:c25a:d00a:e757
892c19:dd:d9:dd:c25:c25a:d00a:e758/1282c19:dd:d9:dd:c25:c25a:d00a:e758
902c19:dd:d9:dd:c25:c25a:d00a:e759/1282c19:dd:d9:dd:c25:c25a:d00a:e759
912c19:dd:d9:dd:c25:c25a:d00a:e75a/1282c19:dd:d9:dd:c25:c25a:d00a:e75a
922c19:dd:d9:dd:c25:c25a:d00a:e75b/1282c19:dd:d9:dd:c25:c25a:d00a:e75b
932c19:dd:d9:dd:c25:c25a:d00a:e75c/1282c19:dd:d9:dd:c25:c25a:d00a:e75c
942c19:dd:d9:dd:c25:c25a:d00a:e75d/1282c19:dd:d9:dd:c25:c25a:d00a:e75d
952c19:dd:d9:dd:c25:c25a:d00a:e75e/1282c19:dd:d9:dd:c25:c25a:d00a:e75e
962c19:dd:d9:dd:c25:c25a:d00a:e75f/1282c19:dd:d9:dd:c25:c25a:d00a:e75f
972c19:dd:d9:dd:c25:c25a:d00a:e760/1282c19:dd:d9:dd:c25:c25a:d00a:e760
982c19:dd:d9:dd:c25:c25a:d00a:e761/1282c19:dd:d9:dd:c25:c25a:d00a:e761
992c19:dd:d9:dd:c25:c25a:d00a:e762/1282c19:dd:d9:dd:c25:c25a:d00a:e762
1002c19:dd:d9:dd:c25:c25a:d00a:e763/1282c19:dd:d9:dd:c25:c25a:d00a:e763
1012c19:dd:d9:dd:c25:c25a:d00a:e764/1282c19:dd:d9:dd:c25:c25a:d00a:e764
1022c19:dd:d9:dd:c25:c25a:d00a:e765/1282c19:dd:d9:dd:c25:c25a:d00a:e765
1032c19:dd:d9:dd:c25:c25a:d00a:e766/1282c19:dd:d9:dd:c25:c25a:d00a:e766
1042c19:dd:d9:dd:c25:c25a:d00a:e767/1282c19:dd:d9:dd:c25:c25a:d00a:e767
1052c19:dd:d9:dd:c25:c25a:d00a:e768/1282c19:dd:d9:dd:c25:c25a:d00a:e768
1062c19:dd:d9:dd:c25:c25a:d00a:e769/1282c19:dd:d9:dd:c25:c25a:d00a:e769
1072c19:dd:d9:dd:c25:c25a:d00a:e76a/1282c19:dd:d9:dd:c25:c25a:d00a:e76a
1082c19:dd:d9:dd:c25:c25a:d00a:e76b/1282c19:dd:d9:dd:c25:c25a:d00a:e76b
1092c19:dd:d9:dd:c25:c25a:d00a:e76c/1282c19:dd:d9:dd:c25:c25a:d00a:e76c
1102c19:dd:d9:dd:c25:c25a:d00a:e76d/1282c19:dd:d9:dd:c25:c25a:d00a:e76d
1112c19:dd:d9:dd:c25:c25a:d00a:e76e/1282c19:dd:d9:dd:c25:c25a:d00a:e76e
1122c19:dd:d9:dd:c25:c25a:d00a:e76f/1282c19:dd:d9:dd:c25:c25a:d00a:e76f
1132c19:dd:d9:dd:c25:c25a:d00a:e770/1282c19:dd:d9:dd:c25:c25a:d00a:e770
1142c19:dd:d9:dd:c25:c25a:d00a:e771/1282c19:dd:d9:dd:c25:c25a:d00a:e771
1152c19:dd:d9:dd:c25:c25a:d00a:e772/1282c19:dd:d9:dd:c25:c25a:d00a:e772
1162c19:dd:d9:dd:c25:c25a:d00a:e773/1282c19:dd:d9:dd:c25:c25a:d00a:e773
1172c19:dd:d9:dd:c25:c25a:d00a:e774/1282c19:dd:d9:dd:c25:c25a:d00a:e774
1182c19:dd:d9:dd:c25:c25a:d00a:e775/1282c19:dd:d9:dd:c25:c25a:d00a:e775
1192c19:dd:d9:dd:c25:c25a:d00a:e776/1282c19:dd:d9:dd:c25:c25a:d00a:e776
1202c19:dd:d9:dd:c25:c25a:d00a:e777/1282c19:dd:d9:dd:c25:c25a:d00a:e777
1212c19:dd:d9:dd:c25:c25a:d00a:e778/1282c19:dd:d9:dd:c25:c25a:d00a:e778
1222c19:dd:d9:dd:c25:c25a:d00a:e779/1282c19:dd:d9:dd:c25:c25a:d00a:e779
1232c19:dd:d9:dd:c25:c25a:d00a:e77a/1282c19:dd:d9:dd:c25:c25a:d00a:e77a
1242c19:dd:d9:dd:c25:c25a:d00a:e77b/1282c19:dd:d9:dd:c25:c25a:d00a:e77b
1252c19:dd:d9:dd:c25:c25a:d00a:e77c/1282c19:dd:d9:dd:c25:c25a:d00a:e77c
1262c19:dd:d9:dd:c25:c25a:d00a:e77d/1282c19:dd:d9:dd:c25:c25a:d00a:e77d
1272c19:dd:d9:dd:c25:c25a:d00a:e77e/1282c19:dd:d9:dd:c25:c25a:d00a:e77e
1282c19:dd:d9:dd:c25:c25a:d00a:e77f/1282c19:dd:d9:dd:c25:c25a:d00a:e77f
1292c19:dd:d9:dd:c25:c25a:d00a:e780/1282c19:dd:d9:dd:c25:c25a:d00a:e780
1302c19:dd:d9:dd:c25:c25a:d00a:e781/1282c19:dd:d9:dd:c25:c25a:d00a:e781
1312c19:dd:d9:dd:c25:c25a:d00a:e782/1282c19:dd:d9:dd:c25:c25a:d00a:e782
1322c19:dd:d9:dd:c25:c25a:d00a:e783/1282c19:dd:d9:dd:c25:c25a:d00a:e783
1332c19:dd:d9:dd:c25:c25a:d00a:e784/1282c19:dd:d9:dd:c25:c25a:d00a:e784
1342c19:dd:d9:dd:c25:c25a:d00a:e785/1282c19:dd:d9:dd:c25:c25a:d00a:e785
1352c19:dd:d9:dd:c25:c25a:d00a:e786/1282c19:dd:d9:dd:c25:c25a:d00a:e786
1362c19:dd:d9:dd:c25:c25a:d00a:e787/1282c19:dd:d9:dd:c25:c25a:d00a:e787
1372c19:dd:d9:dd:c25:c25a:d00a:e788/1282c19:dd:d9:dd:c25:c25a:d00a:e788
1382c19:dd:d9:dd:c25:c25a:d00a:e789/1282c19:dd:d9:dd:c25:c25a:d00a:e789
1392c19:dd:d9:dd:c25:c25a:d00a:e78a/1282c19:dd:d9:dd:c25:c25a:d00a:e78a
1402c19:dd:d9:dd:c25:c25a:d00a:e78b/1282c19:dd:d9:dd:c25:c25a:d00a:e78b
1412c19:dd:d9:dd:c25:c25a:d00a:e78c/1282c19:dd:d9:dd:c25:c25a:d00a:e78c
1422c19:dd:d9:dd:c25:c25a:d00a:e78d/1282c19:dd:d9:dd:c25:c25a:d00a:e78d
1432c19:dd:d9:dd:c25:c25a:d00a:e78e/1282c19:dd:d9:dd:c25:c25a:d00a:e78e
1442c19:dd:d9:dd:c25:c25a:d00a:e78f/1282c19:dd:d9:dd:c25:c25a:d00a:e78f
1452c19:dd:d9:dd:c25:c25a:d00a:e790/1282c19:dd:d9:dd:c25:c25a:d00a:e790
1462c19:dd:d9:dd:c25:c25a:d00a:e791/1282c19:dd:d9:dd:c25:c25a:d00a:e791
1472c19:dd:d9:dd:c25:c25a:d00a:e792/1282c19:dd:d9:dd:c25:c25a:d00a:e792
1482c19:dd:d9:dd:c25:c25a:d00a:e793/1282c19:dd:d9:dd:c25:c25a:d00a:e793
1492c19:dd:d9:dd:c25:c25a:d00a:e794/1282c19:dd:d9:dd:c25:c25a:d00a:e794
1502c19:dd:d9:dd:c25:c25a:d00a:e795/1282c19:dd:d9:dd:c25:c25a:d00a:e795
1512c19:dd:d9:dd:c25:c25a:d00a:e796/1282c19:dd:d9:dd:c25:c25a:d00a:e796
1522c19:dd:d9:dd:c25:c25a:d00a:e797/1282c19:dd:d9:dd:c25:c25a:d00a:e797
1532c19:dd:d9:dd:c25:c25a:d00a:e798/1282c19:dd:d9:dd:c25:c25a:d00a:e798
1542c19:dd:d9:dd:c25:c25a:d00a:e799/1282c19:dd:d9:dd:c25:c25a:d00a:e799
1552c19:dd:d9:dd:c25:c25a:d00a:e79a/1282c19:dd:d9:dd:c25:c25a:d00a:e79a
1562c19:dd:d9:dd:c25:c25a:d00a:e79b/1282c19:dd:d9:dd:c25:c25a:d00a:e79b
1572c19:dd:d9:dd:c25:c25a:d00a:e79c/1282c19:dd:d9:dd:c25:c25a:d00a:e79c
1582c19:dd:d9:dd:c25:c25a:d00a:e79d/1282c19:dd:d9:dd:c25:c25a:d00a:e79d
1592c19:dd:d9:dd:c25:c25a:d00a:e79e/1282c19:dd:d9:dd:c25:c25a:d00a:e79e
1602c19:dd:d9:dd:c25:c25a:d00a:e79f/1282c19:dd:d9:dd:c25:c25a:d00a:e79f
1612c19:dd:d9:dd:c25:c25a:d00a:e7a0/1282c19:dd:d9:dd:c25:c25a:d00a:e7a0
1622c19:dd:d9:dd:c25:c25a:d00a:e7a1/1282c19:dd:d9:dd:c25:c25a:d00a:e7a1
1632c19:dd:d9:dd:c25:c25a:d00a:e7a2/1282c19:dd:d9:dd:c25:c25a:d00a:e7a2
1642c19:dd:d9:dd:c25:c25a:d00a:e7a3/1282c19:dd:d9:dd:c25:c25a:d00a:e7a3
1652c19:dd:d9:dd:c25:c25a:d00a:e7a4/1282c19:dd:d9:dd:c25:c25a:d00a:e7a4
1662c19:dd:d9:dd:c25:c25a:d00a:e7a5/1282c19:dd:d9:dd:c25:c25a:d00a:e7a5
1672c19:dd:d9:dd:c25:c25a:d00a:e7a6/1282c19:dd:d9:dd:c25:c25a:d00a:e7a6
1682c19:dd:d9:dd:c25:c25a:d00a:e7a7/1282c19:dd:d9:dd:c25:c25a:d00a:e7a7
1692c19:dd:d9:dd:c25:c25a:d00a:e7a8/1282c19:dd:d9:dd:c25:c25a:d00a:e7a8
1702c19:dd:d9:dd:c25:c25a:d00a:e7a9/1282c19:dd:d9:dd:c25:c25a:d00a:e7a9
1712c19:dd:d9:dd:c25:c25a:d00a:e7aa/1282c19:dd:d9:dd:c25:c25a:d00a:e7aa
1722c19:dd:d9:dd:c25:c25a:d00a:e7ab/1282c19:dd:d9:dd:c25:c25a:d00a:e7ab
1732c19:dd:d9:dd:c25:c25a:d00a:e7ac/1282c19:dd:d9:dd:c25:c25a:d00a:e7ac
1742c19:dd:d9:dd:c25:c25a:d00a:e7ad/1282c19:dd:d9:dd:c25:c25a:d00a:e7ad
1752c19:dd:d9:dd:c25:c25a:d00a:e7ae/1282c19:dd:d9:dd:c25:c25a:d00a:e7ae
1762c19:dd:d9:dd:c25:c25a:d00a:e7af/1282c19:dd:d9:dd:c25:c25a:d00a:e7af
1772c19:dd:d9:dd:c25:c25a:d00a:e7b0/1282c19:dd:d9:dd:c25:c25a:d00a:e7b0
1782c19:dd:d9:dd:c25:c25a:d00a:e7b1/1282c19:dd:d9:dd:c25:c25a:d00a:e7b1
1792c19:dd:d9:dd:c25:c25a:d00a:e7b2/1282c19:dd:d9:dd:c25:c25a:d00a:e7b2
1802c19:dd:d9:dd:c25:c25a:d00a:e7b3/1282c19:dd:d9:dd:c25:c25a:d00a:e7b3
1812c19:dd:d9:dd:c25:c25a:d00a:e7b4/1282c19:dd:d9:dd:c25:c25a:d00a:e7b4
1822c19:dd:d9:dd:c25:c25a:d00a:e7b5/1282c19:dd:d9:dd:c25:c25a:d00a:e7b5
1832c19:dd:d9:dd:c25:c25a:d00a:e7b6/1282c19:dd:d9:dd:c25:c25a:d00a:e7b6
1842c19:dd:d9:dd:c25:c25a:d00a:e7b7/1282c19:dd:d9:dd:c25:c25a:d00a:e7b7
1852c19:dd:d9:dd:c25:c25a:d00a:e7b8/1282c19:dd:d9:dd:c25:c25a:d00a:e7b8
1862c19:dd:d9:dd:c25:c25a:d00a:e7b9/1282c19:dd:d9:dd:c25:c25a:d00a:e7b9
1872c19:dd:d9:dd:c25:c25a:d00a:e7ba/1282c19:dd:d9:dd:c25:c25a:d00a:e7ba
1882c19:dd:d9:dd:c25:c25a:d00a:e7bb/1282c19:dd:d9:dd:c25:c25a:d00a:e7bb
1892c19:dd:d9:dd:c25:c25a:d00a:e7bc/1282c19:dd:d9:dd:c25:c25a:d00a:e7bc
1902c19:dd:d9:dd:c25:c25a:d00a:e7bd/1282c19:dd:d9:dd:c25:c25a:d00a:e7bd
1912c19:dd:d9:dd:c25:c25a:d00a:e7be/1282c19:dd:d9:dd:c25:c25a:d00a:e7be
1922c19:dd:d9:dd:c25:c25a:d00a:e7bf/1282c19:dd:d9:dd:c25:c25a:d00a:e7bf
1932c19:dd:d9:dd:c25:c25a:d00a:e7c0/1282c19:dd:d9:dd:c25:c25a:d00a:e7c0
1942c19:dd:d9:dd:c25:c25a:d00a:e7c1/1282c19:dd:d9:dd:c25:c25a:d00a:e7c1
1952c19:dd:d9:dd:c25:c25a:d00a:e7c2/1282c19:dd:d9:dd:c25:c25a:d00a:e7c2
1962c19:dd:d9:dd:c25:c25a:d00a:e7c3/1282c19:dd:d9:dd:c25:c25a:d00a:e7c3
1972c19:dd:d9:dd:c25:c25a:d00a:e7c4/1282c19:dd:d9:dd:c25:c25a:d00a:e7c4
1982c19:dd:d9:dd:c25:c25a:d00a:e7c5/1282c19:dd:d9:dd:c25:c25a:d00a:e7c5
1992c19:dd:d9:dd:c25:c25a:d00a:e7c6/1282c19:dd:d9:dd:c25:c25a:d00a:e7c6
2002c19:dd:d9:dd:c25:c25a:d00a:e7c7/1282c19:dd:d9:dd:c25:c25a:d00a:e7c7
2012c19:dd:d9:dd:c25:c25a:d00a:e7c8/1282c19:dd:d9:dd:c25:c25a:d00a:e7c8
2022c19:dd:d9:dd:c25:c25a:d00a:e7c9/1282c19:dd:d9:dd:c25:c25a:d00a:e7c9
2032c19:dd:d9:dd:c25:c25a:d00a:e7ca/1282c19:dd:d9:dd:c25:c25a:d00a:e7ca
2042c19:dd:d9:dd:c25:c25a:d00a:e7cb/1282c19:dd:d9:dd:c25:c25a:d00a:e7cb
2052c19:dd:d9:dd:c25:c25a:d00a:e7cc/1282c19:dd:d9:dd:c25:c25a:d00a:e7cc
2062c19:dd:d9:dd:c25:c25a:d00a:e7cd/1282c19:dd:d9:dd:c25:c25a:d00a:e7cd
2072c19:dd:d9:dd:c25:c25a:d00a:e7ce/1282c19:dd:d9:dd:c25:c25a:d00a:e7ce
2082c19:dd:d9:dd:c25:c25a:d00a:e7cf/1282c19:dd:d9:dd:c25:c25a:d00a:e7cf
2092c19:dd:d9:dd:c25:c25a:d00a:e7d0/1282c19:dd:d9:dd:c25:c25a:d00a:e7d0
2102c19:dd:d9:dd:c25:c25a:d00a:e7d1/1282c19:dd:d9:dd:c25:c25a:d00a:e7d1
2112c19:dd:d9:dd:c25:c25a:d00a:e7d2/1282c19:dd:d9:dd:c25:c25a:d00a:e7d2
2122c19:dd:d9:dd:c25:c25a:d00a:e7d3/1282c19:dd:d9:dd:c25:c25a:d00a:e7d3
2132c19:dd:d9:dd:c25:c25a:d00a:e7d4/1282c19:dd:d9:dd:c25:c25a:d00a:e7d4
2142c19:dd:d9:dd:c25:c25a:d00a:e7d5/1282c19:dd:d9:dd:c25:c25a:d00a:e7d5
2152c19:dd:d9:dd:c25:c25a:d00a:e7d6/1282c19:dd:d9:dd:c25:c25a:d00a:e7d6
2162c19:dd:d9:dd:c25:c25a:d00a:e7d7/1282c19:dd:d9:dd:c25:c25a:d00a:e7d7
2172c19:dd:d9:dd:c25:c25a:d00a:e7d8/1282c19:dd:d9:dd:c25:c25a:d00a:e7d8
2182c19:dd:d9:dd:c25:c25a:d00a:e7d9/1282c19:dd:d9:dd:c25:c25a:d00a:e7d9
2192c19:dd:d9:dd:c25:c25a:d00a:e7da/1282c19:dd:d9:dd:c25:c25a:d00a:e7da
2202c19:dd:d9:dd:c25:c25a:d00a:e7db/1282c19:dd:d9:dd:c25:c25a:d00a:e7db
2212c19:dd:d9:dd:c25:c25a:d00a:e7dc/1282c19:dd:d9:dd:c25:c25a:d00a:e7dc
2222c19:dd:d9:dd:c25:c25a:d00a:e7dd/1282c19:dd:d9:dd:c25:c25a:d00a:e7dd
2232c19:dd:d9:dd:c25:c25a:d00a:e7de/1282c19:dd:d9:dd:c25:c25a:d00a:e7de
2242c19:dd:d9:dd:c25:c25a:d00a:e7df/1282c19:dd:d9:dd:c25:c25a:d00a:e7df
2252c19:dd:d9:dd:c25:c25a:d00a:e7e0/1282c19:dd:d9:dd:c25:c25a:d00a:e7e0
2262c19:dd:d9:dd:c25:c25a:d00a:e7e1/1282c19:dd:d9:dd:c25:c25a:d00a:e7e1
2272c19:dd:d9:dd:c25:c25a:d00a:e7e2/1282c19:dd:d9:dd:c25:c25a:d00a:e7e2
2282c19:dd:d9:dd:c25:c25a:d00a:e7e3/1282c19:dd:d9:dd:c25:c25a:d00a:e7e3
2292c19:dd:d9:dd:c25:c25a:d00a:e7e4/1282c19:dd:d9:dd:c25:c25a:d00a:e7e4
2302c19:dd:d9:dd:c25:c25a:d00a:e7e5/1282c19:dd:d9:dd:c25:c25a:d00a:e7e5
2312c19:dd:d9:dd:c25:c25a:d00a:e7e6/1282c19:dd:d9:dd:c25:c25a:d00a:e7e6
2322c19:dd:d9:dd:c25:c25a:d00a:e7e7/1282c19:dd:d9:dd:c25:c25a:d00a:e7e7
2332c19:dd:d9:dd:c25:c25a:d00a:e7e8/1282c19:dd:d9:dd:c25:c25a:d00a:e7e8
2342c19:dd:d9:dd:c25:c25a:d00a:e7e9/1282c19:dd:d9:dd:c25:c25a:d00a:e7e9
2352c19:dd:d9:dd:c25:c25a:d00a:e7ea/1282c19:dd:d9:dd:c25:c25a:d00a:e7ea
2362c19:dd:d9:dd:c25:c25a:d00a:e7eb/1282c19:dd:d9:dd:c25:c25a:d00a:e7eb
2372c19:dd:d9:dd:c25:c25a:d00a:e7ec/1282c19:dd:d9:dd:c25:c25a:d00a:e7ec
2382c19:dd:d9:dd:c25:c25a:d00a:e7ed/1282c19:dd:d9:dd:c25:c25a:d00a:e7ed
2392c19:dd:d9:dd:c25:c25a:d00a:e7ee/1282c19:dd:d9:dd:c25:c25a:d00a:e7ee
2402c19:dd:d9:dd:c25:c25a:d00a:e7ef/1282c19:dd:d9:dd:c25:c25a:d00a:e7ef
2412c19:dd:d9:dd:c25:c25a:d00a:e7f0/1282c19:dd:d9:dd:c25:c25a:d00a:e7f0
2422c19:dd:d9:dd:c25:c25a:d00a:e7f1/1282c19:dd:d9:dd:c25:c25a:d00a:e7f1
2432c19:dd:d9:dd:c25:c25a:d00a:e7f2/1282c19:dd:d9:dd:c25:c25a:d00a:e7f2
2442c19:dd:d9:dd:c25:c25a:d00a:e7f3/1282c19:dd:d9:dd:c25:c25a:d00a:e7f3
2452c19:dd:d9:dd:c25:c25a:d00a:e7f4/1282c19:dd:d9:dd:c25:c25a:d00a:e7f4
2462c19:dd:d9:dd:c25:c25a:d00a:e7f5/1282c19:dd:d9:dd:c25:c25a:d00a:e7f5
2472c19:dd:d9:dd:c25:c25a:d00a:e7f6/1282c19:dd:d9:dd:c25:c25a:d00a:e7f6
2482c19:dd:d9:dd:c25:c25a:d00a:e7f7/1282c19:dd:d9:dd:c25:c25a:d00a:e7f7
2492c19:dd:d9:dd:c25:c25a:d00a:e7f8/1282c19:dd:d9:dd:c25:c25a:d00a:e7f8
2502c19:dd:d9:dd:c25:c25a:d00a:e7f9/1282c19:dd:d9:dd:c25:c25a:d00a:e7f9
2512c19:dd:d9:dd:c25:c25a:d00a:e7fa/1282c19:dd:d9:dd:c25:c25a:d00a:e7fa
2522c19:dd:d9:dd:c25:c25a:d00a:e7fb/1282c19:dd:d9:dd:c25:c25a:d00a:e7fb
2532c19:dd:d9:dd:c25:c25a:d00a:e7fc/1282c19:dd:d9:dd:c25:c25a:d00a:e7fc
2542c19:dd:d9:dd:c25:c25a:d00a:e7fd/1282c19:dd:d9:dd:c25:c25a:d00a:e7fd
2552c19:dd:d9:dd:c25:c25a:d00a:e7fe/1282c19:dd:d9:dd:c25:c25a:d00a:e7fe
2562c19:dd:d9:dd:c25:c25a:d00a:e7ff/1282c19:dd:d9:dd:c25:c25a:d00a:e7ff

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.