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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:dd0:ec00:c25:c25:ddea:600/120
First address
2c19:dd:dd0:ec00:c25:c25:ddea:600
Last address
2c19:dd:dd0:ec00:c25:c25:ddea:6ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0dd0:ec00:0c25:0c25:ddea:0600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.0.a.e.d.d.5.2.c.0.5.2.c.0.0.0.c.e.0.d.d.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:dd0:ec00:c25:c25:ddea:600/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:dd0:ec00:c25:c25:ddea:600/1282c19:dd:dd0:ec00:c25:c25:ddea:600
22c19:dd:dd0:ec00:c25:c25:ddea:601/1282c19:dd:dd0:ec00:c25:c25:ddea:601
32c19:dd:dd0:ec00:c25:c25:ddea:602/1282c19:dd:dd0:ec00:c25:c25:ddea:602
42c19:dd:dd0:ec00:c25:c25:ddea:603/1282c19:dd:dd0:ec00:c25:c25:ddea:603
52c19:dd:dd0:ec00:c25:c25:ddea:604/1282c19:dd:dd0:ec00:c25:c25:ddea:604
62c19:dd:dd0:ec00:c25:c25:ddea:605/1282c19:dd:dd0:ec00:c25:c25:ddea:605
72c19:dd:dd0:ec00:c25:c25:ddea:606/1282c19:dd:dd0:ec00:c25:c25:ddea:606
82c19:dd:dd0:ec00:c25:c25:ddea:607/1282c19:dd:dd0:ec00:c25:c25:ddea:607
92c19:dd:dd0:ec00:c25:c25:ddea:608/1282c19:dd:dd0:ec00:c25:c25:ddea:608
102c19:dd:dd0:ec00:c25:c25:ddea:609/1282c19:dd:dd0:ec00:c25:c25:ddea:609
112c19:dd:dd0:ec00:c25:c25:ddea:60a/1282c19:dd:dd0:ec00:c25:c25:ddea:60a
122c19:dd:dd0:ec00:c25:c25:ddea:60b/1282c19:dd:dd0:ec00:c25:c25:ddea:60b
132c19:dd:dd0:ec00:c25:c25:ddea:60c/1282c19:dd:dd0:ec00:c25:c25:ddea:60c
142c19:dd:dd0:ec00:c25:c25:ddea:60d/1282c19:dd:dd0:ec00:c25:c25:ddea:60d
152c19:dd:dd0:ec00:c25:c25:ddea:60e/1282c19:dd:dd0:ec00:c25:c25:ddea:60e
162c19:dd:dd0:ec00:c25:c25:ddea:60f/1282c19:dd:dd0:ec00:c25:c25:ddea:60f
172c19:dd:dd0:ec00:c25:c25:ddea:610/1282c19:dd:dd0:ec00:c25:c25:ddea:610
182c19:dd:dd0:ec00:c25:c25:ddea:611/1282c19:dd:dd0:ec00:c25:c25:ddea:611
192c19:dd:dd0:ec00:c25:c25:ddea:612/1282c19:dd:dd0:ec00:c25:c25:ddea:612
202c19:dd:dd0:ec00:c25:c25:ddea:613/1282c19:dd:dd0:ec00:c25:c25:ddea:613
212c19:dd:dd0:ec00:c25:c25:ddea:614/1282c19:dd:dd0:ec00:c25:c25:ddea:614
222c19:dd:dd0:ec00:c25:c25:ddea:615/1282c19:dd:dd0:ec00:c25:c25:ddea:615
232c19:dd:dd0:ec00:c25:c25:ddea:616/1282c19:dd:dd0:ec00:c25:c25:ddea:616
242c19:dd:dd0:ec00:c25:c25:ddea:617/1282c19:dd:dd0:ec00:c25:c25:ddea:617
252c19:dd:dd0:ec00:c25:c25:ddea:618/1282c19:dd:dd0:ec00:c25:c25:ddea:618
262c19:dd:dd0:ec00:c25:c25:ddea:619/1282c19:dd:dd0:ec00:c25:c25:ddea:619
272c19:dd:dd0:ec00:c25:c25:ddea:61a/1282c19:dd:dd0:ec00:c25:c25:ddea:61a
282c19:dd:dd0:ec00:c25:c25:ddea:61b/1282c19:dd:dd0:ec00:c25:c25:ddea:61b
292c19:dd:dd0:ec00:c25:c25:ddea:61c/1282c19:dd:dd0:ec00:c25:c25:ddea:61c
302c19:dd:dd0:ec00:c25:c25:ddea:61d/1282c19:dd:dd0:ec00:c25:c25:ddea:61d
312c19:dd:dd0:ec00:c25:c25:ddea:61e/1282c19:dd:dd0:ec00:c25:c25:ddea:61e
322c19:dd:dd0:ec00:c25:c25:ddea:61f/1282c19:dd:dd0:ec00:c25:c25:ddea:61f
332c19:dd:dd0:ec00:c25:c25:ddea:620/1282c19:dd:dd0:ec00:c25:c25:ddea:620
342c19:dd:dd0:ec00:c25:c25:ddea:621/1282c19:dd:dd0:ec00:c25:c25:ddea:621
352c19:dd:dd0:ec00:c25:c25:ddea:622/1282c19:dd:dd0:ec00:c25:c25:ddea:622
362c19:dd:dd0:ec00:c25:c25:ddea:623/1282c19:dd:dd0:ec00:c25:c25:ddea:623
372c19:dd:dd0:ec00:c25:c25:ddea:624/1282c19:dd:dd0:ec00:c25:c25:ddea:624
382c19:dd:dd0:ec00:c25:c25:ddea:625/1282c19:dd:dd0:ec00:c25:c25:ddea:625
392c19:dd:dd0:ec00:c25:c25:ddea:626/1282c19:dd:dd0:ec00:c25:c25:ddea:626
402c19:dd:dd0:ec00:c25:c25:ddea:627/1282c19:dd:dd0:ec00:c25:c25:ddea:627
412c19:dd:dd0:ec00:c25:c25:ddea:628/1282c19:dd:dd0:ec00:c25:c25:ddea:628
422c19:dd:dd0:ec00:c25:c25:ddea:629/1282c19:dd:dd0:ec00:c25:c25:ddea:629
432c19:dd:dd0:ec00:c25:c25:ddea:62a/1282c19:dd:dd0:ec00:c25:c25:ddea:62a
442c19:dd:dd0:ec00:c25:c25:ddea:62b/1282c19:dd:dd0:ec00:c25:c25:ddea:62b
452c19:dd:dd0:ec00:c25:c25:ddea:62c/1282c19:dd:dd0:ec00:c25:c25:ddea:62c
462c19:dd:dd0:ec00:c25:c25:ddea:62d/1282c19:dd:dd0:ec00:c25:c25:ddea:62d
472c19:dd:dd0:ec00:c25:c25:ddea:62e/1282c19:dd:dd0:ec00:c25:c25:ddea:62e
482c19:dd:dd0:ec00:c25:c25:ddea:62f/1282c19:dd:dd0:ec00:c25:c25:ddea:62f
492c19:dd:dd0:ec00:c25:c25:ddea:630/1282c19:dd:dd0:ec00:c25:c25:ddea:630
502c19:dd:dd0:ec00:c25:c25:ddea:631/1282c19:dd:dd0:ec00:c25:c25:ddea:631
512c19:dd:dd0:ec00:c25:c25:ddea:632/1282c19:dd:dd0:ec00:c25:c25:ddea:632
522c19:dd:dd0:ec00:c25:c25:ddea:633/1282c19:dd:dd0:ec00:c25:c25:ddea:633
532c19:dd:dd0:ec00:c25:c25:ddea:634/1282c19:dd:dd0:ec00:c25:c25:ddea:634
542c19:dd:dd0:ec00:c25:c25:ddea:635/1282c19:dd:dd0:ec00:c25:c25:ddea:635
552c19:dd:dd0:ec00:c25:c25:ddea:636/1282c19:dd:dd0:ec00:c25:c25:ddea:636
562c19:dd:dd0:ec00:c25:c25:ddea:637/1282c19:dd:dd0:ec00:c25:c25:ddea:637
572c19:dd:dd0:ec00:c25:c25:ddea:638/1282c19:dd:dd0:ec00:c25:c25:ddea:638
582c19:dd:dd0:ec00:c25:c25:ddea:639/1282c19:dd:dd0:ec00:c25:c25:ddea:639
592c19:dd:dd0:ec00:c25:c25:ddea:63a/1282c19:dd:dd0:ec00:c25:c25:ddea:63a
602c19:dd:dd0:ec00:c25:c25:ddea:63b/1282c19:dd:dd0:ec00:c25:c25:ddea:63b
612c19:dd:dd0:ec00:c25:c25:ddea:63c/1282c19:dd:dd0:ec00:c25:c25:ddea:63c
622c19:dd:dd0:ec00:c25:c25:ddea:63d/1282c19:dd:dd0:ec00:c25:c25:ddea:63d
632c19:dd:dd0:ec00:c25:c25:ddea:63e/1282c19:dd:dd0:ec00:c25:c25:ddea:63e
642c19:dd:dd0:ec00:c25:c25:ddea:63f/1282c19:dd:dd0:ec00:c25:c25:ddea:63f
652c19:dd:dd0:ec00:c25:c25:ddea:640/1282c19:dd:dd0:ec00:c25:c25:ddea:640
662c19:dd:dd0:ec00:c25:c25:ddea:641/1282c19:dd:dd0:ec00:c25:c25:ddea:641
672c19:dd:dd0:ec00:c25:c25:ddea:642/1282c19:dd:dd0:ec00:c25:c25:ddea:642
682c19:dd:dd0:ec00:c25:c25:ddea:643/1282c19:dd:dd0:ec00:c25:c25:ddea:643
692c19:dd:dd0:ec00:c25:c25:ddea:644/1282c19:dd:dd0:ec00:c25:c25:ddea:644
702c19:dd:dd0:ec00:c25:c25:ddea:645/1282c19:dd:dd0:ec00:c25:c25:ddea:645
712c19:dd:dd0:ec00:c25:c25:ddea:646/1282c19:dd:dd0:ec00:c25:c25:ddea:646
722c19:dd:dd0:ec00:c25:c25:ddea:647/1282c19:dd:dd0:ec00:c25:c25:ddea:647
732c19:dd:dd0:ec00:c25:c25:ddea:648/1282c19:dd:dd0:ec00:c25:c25:ddea:648
742c19:dd:dd0:ec00:c25:c25:ddea:649/1282c19:dd:dd0:ec00:c25:c25:ddea:649
752c19:dd:dd0:ec00:c25:c25:ddea:64a/1282c19:dd:dd0:ec00:c25:c25:ddea:64a
762c19:dd:dd0:ec00:c25:c25:ddea:64b/1282c19:dd:dd0:ec00:c25:c25:ddea:64b
772c19:dd:dd0:ec00:c25:c25:ddea:64c/1282c19:dd:dd0:ec00:c25:c25:ddea:64c
782c19:dd:dd0:ec00:c25:c25:ddea:64d/1282c19:dd:dd0:ec00:c25:c25:ddea:64d
792c19:dd:dd0:ec00:c25:c25:ddea:64e/1282c19:dd:dd0:ec00:c25:c25:ddea:64e
802c19:dd:dd0:ec00:c25:c25:ddea:64f/1282c19:dd:dd0:ec00:c25:c25:ddea:64f
812c19:dd:dd0:ec00:c25:c25:ddea:650/1282c19:dd:dd0:ec00:c25:c25:ddea:650
822c19:dd:dd0:ec00:c25:c25:ddea:651/1282c19:dd:dd0:ec00:c25:c25:ddea:651
832c19:dd:dd0:ec00:c25:c25:ddea:652/1282c19:dd:dd0:ec00:c25:c25:ddea:652
842c19:dd:dd0:ec00:c25:c25:ddea:653/1282c19:dd:dd0:ec00:c25:c25:ddea:653
852c19:dd:dd0:ec00:c25:c25:ddea:654/1282c19:dd:dd0:ec00:c25:c25:ddea:654
862c19:dd:dd0:ec00:c25:c25:ddea:655/1282c19:dd:dd0:ec00:c25:c25:ddea:655
872c19:dd:dd0:ec00:c25:c25:ddea:656/1282c19:dd:dd0:ec00:c25:c25:ddea:656
882c19:dd:dd0:ec00:c25:c25:ddea:657/1282c19:dd:dd0:ec00:c25:c25:ddea:657
892c19:dd:dd0:ec00:c25:c25:ddea:658/1282c19:dd:dd0:ec00:c25:c25:ddea:658
902c19:dd:dd0:ec00:c25:c25:ddea:659/1282c19:dd:dd0:ec00:c25:c25:ddea:659
912c19:dd:dd0:ec00:c25:c25:ddea:65a/1282c19:dd:dd0:ec00:c25:c25:ddea:65a
922c19:dd:dd0:ec00:c25:c25:ddea:65b/1282c19:dd:dd0:ec00:c25:c25:ddea:65b
932c19:dd:dd0:ec00:c25:c25:ddea:65c/1282c19:dd:dd0:ec00:c25:c25:ddea:65c
942c19:dd:dd0:ec00:c25:c25:ddea:65d/1282c19:dd:dd0:ec00:c25:c25:ddea:65d
952c19:dd:dd0:ec00:c25:c25:ddea:65e/1282c19:dd:dd0:ec00:c25:c25:ddea:65e
962c19:dd:dd0:ec00:c25:c25:ddea:65f/1282c19:dd:dd0:ec00:c25:c25:ddea:65f
972c19:dd:dd0:ec00:c25:c25:ddea:660/1282c19:dd:dd0:ec00:c25:c25:ddea:660
982c19:dd:dd0:ec00:c25:c25:ddea:661/1282c19:dd:dd0:ec00:c25:c25:ddea:661
992c19:dd:dd0:ec00:c25:c25:ddea:662/1282c19:dd:dd0:ec00:c25:c25:ddea:662
1002c19:dd:dd0:ec00:c25:c25:ddea:663/1282c19:dd:dd0:ec00:c25:c25:ddea:663
1012c19:dd:dd0:ec00:c25:c25:ddea:664/1282c19:dd:dd0:ec00:c25:c25:ddea:664
1022c19:dd:dd0:ec00:c25:c25:ddea:665/1282c19:dd:dd0:ec00:c25:c25:ddea:665
1032c19:dd:dd0:ec00:c25:c25:ddea:666/1282c19:dd:dd0:ec00:c25:c25:ddea:666
1042c19:dd:dd0:ec00:c25:c25:ddea:667/1282c19:dd:dd0:ec00:c25:c25:ddea:667
1052c19:dd:dd0:ec00:c25:c25:ddea:668/1282c19:dd:dd0:ec00:c25:c25:ddea:668
1062c19:dd:dd0:ec00:c25:c25:ddea:669/1282c19:dd:dd0:ec00:c25:c25:ddea:669
1072c19:dd:dd0:ec00:c25:c25:ddea:66a/1282c19:dd:dd0:ec00:c25:c25:ddea:66a
1082c19:dd:dd0:ec00:c25:c25:ddea:66b/1282c19:dd:dd0:ec00:c25:c25:ddea:66b
1092c19:dd:dd0:ec00:c25:c25:ddea:66c/1282c19:dd:dd0:ec00:c25:c25:ddea:66c
1102c19:dd:dd0:ec00:c25:c25:ddea:66d/1282c19:dd:dd0:ec00:c25:c25:ddea:66d
1112c19:dd:dd0:ec00:c25:c25:ddea:66e/1282c19:dd:dd0:ec00:c25:c25:ddea:66e
1122c19:dd:dd0:ec00:c25:c25:ddea:66f/1282c19:dd:dd0:ec00:c25:c25:ddea:66f
1132c19:dd:dd0:ec00:c25:c25:ddea:670/1282c19:dd:dd0:ec00:c25:c25:ddea:670
1142c19:dd:dd0:ec00:c25:c25:ddea:671/1282c19:dd:dd0:ec00:c25:c25:ddea:671
1152c19:dd:dd0:ec00:c25:c25:ddea:672/1282c19:dd:dd0:ec00:c25:c25:ddea:672
1162c19:dd:dd0:ec00:c25:c25:ddea:673/1282c19:dd:dd0:ec00:c25:c25:ddea:673
1172c19:dd:dd0:ec00:c25:c25:ddea:674/1282c19:dd:dd0:ec00:c25:c25:ddea:674
1182c19:dd:dd0:ec00:c25:c25:ddea:675/1282c19:dd:dd0:ec00:c25:c25:ddea:675
1192c19:dd:dd0:ec00:c25:c25:ddea:676/1282c19:dd:dd0:ec00:c25:c25:ddea:676
1202c19:dd:dd0:ec00:c25:c25:ddea:677/1282c19:dd:dd0:ec00:c25:c25:ddea:677
1212c19:dd:dd0:ec00:c25:c25:ddea:678/1282c19:dd:dd0:ec00:c25:c25:ddea:678
1222c19:dd:dd0:ec00:c25:c25:ddea:679/1282c19:dd:dd0:ec00:c25:c25:ddea:679
1232c19:dd:dd0:ec00:c25:c25:ddea:67a/1282c19:dd:dd0:ec00:c25:c25:ddea:67a
1242c19:dd:dd0:ec00:c25:c25:ddea:67b/1282c19:dd:dd0:ec00:c25:c25:ddea:67b
1252c19:dd:dd0:ec00:c25:c25:ddea:67c/1282c19:dd:dd0:ec00:c25:c25:ddea:67c
1262c19:dd:dd0:ec00:c25:c25:ddea:67d/1282c19:dd:dd0:ec00:c25:c25:ddea:67d
1272c19:dd:dd0:ec00:c25:c25:ddea:67e/1282c19:dd:dd0:ec00:c25:c25:ddea:67e
1282c19:dd:dd0:ec00:c25:c25:ddea:67f/1282c19:dd:dd0:ec00:c25:c25:ddea:67f
1292c19:dd:dd0:ec00:c25:c25:ddea:680/1282c19:dd:dd0:ec00:c25:c25:ddea:680
1302c19:dd:dd0:ec00:c25:c25:ddea:681/1282c19:dd:dd0:ec00:c25:c25:ddea:681
1312c19:dd:dd0:ec00:c25:c25:ddea:682/1282c19:dd:dd0:ec00:c25:c25:ddea:682
1322c19:dd:dd0:ec00:c25:c25:ddea:683/1282c19:dd:dd0:ec00:c25:c25:ddea:683
1332c19:dd:dd0:ec00:c25:c25:ddea:684/1282c19:dd:dd0:ec00:c25:c25:ddea:684
1342c19:dd:dd0:ec00:c25:c25:ddea:685/1282c19:dd:dd0:ec00:c25:c25:ddea:685
1352c19:dd:dd0:ec00:c25:c25:ddea:686/1282c19:dd:dd0:ec00:c25:c25:ddea:686
1362c19:dd:dd0:ec00:c25:c25:ddea:687/1282c19:dd:dd0:ec00:c25:c25:ddea:687
1372c19:dd:dd0:ec00:c25:c25:ddea:688/1282c19:dd:dd0:ec00:c25:c25:ddea:688
1382c19:dd:dd0:ec00:c25:c25:ddea:689/1282c19:dd:dd0:ec00:c25:c25:ddea:689
1392c19:dd:dd0:ec00:c25:c25:ddea:68a/1282c19:dd:dd0:ec00:c25:c25:ddea:68a
1402c19:dd:dd0:ec00:c25:c25:ddea:68b/1282c19:dd:dd0:ec00:c25:c25:ddea:68b
1412c19:dd:dd0:ec00:c25:c25:ddea:68c/1282c19:dd:dd0:ec00:c25:c25:ddea:68c
1422c19:dd:dd0:ec00:c25:c25:ddea:68d/1282c19:dd:dd0:ec00:c25:c25:ddea:68d
1432c19:dd:dd0:ec00:c25:c25:ddea:68e/1282c19:dd:dd0:ec00:c25:c25:ddea:68e
1442c19:dd:dd0:ec00:c25:c25:ddea:68f/1282c19:dd:dd0:ec00:c25:c25:ddea:68f
1452c19:dd:dd0:ec00:c25:c25:ddea:690/1282c19:dd:dd0:ec00:c25:c25:ddea:690
1462c19:dd:dd0:ec00:c25:c25:ddea:691/1282c19:dd:dd0:ec00:c25:c25:ddea:691
1472c19:dd:dd0:ec00:c25:c25:ddea:692/1282c19:dd:dd0:ec00:c25:c25:ddea:692
1482c19:dd:dd0:ec00:c25:c25:ddea:693/1282c19:dd:dd0:ec00:c25:c25:ddea:693
1492c19:dd:dd0:ec00:c25:c25:ddea:694/1282c19:dd:dd0:ec00:c25:c25:ddea:694
1502c19:dd:dd0:ec00:c25:c25:ddea:695/1282c19:dd:dd0:ec00:c25:c25:ddea:695
1512c19:dd:dd0:ec00:c25:c25:ddea:696/1282c19:dd:dd0:ec00:c25:c25:ddea:696
1522c19:dd:dd0:ec00:c25:c25:ddea:697/1282c19:dd:dd0:ec00:c25:c25:ddea:697
1532c19:dd:dd0:ec00:c25:c25:ddea:698/1282c19:dd:dd0:ec00:c25:c25:ddea:698
1542c19:dd:dd0:ec00:c25:c25:ddea:699/1282c19:dd:dd0:ec00:c25:c25:ddea:699
1552c19:dd:dd0:ec00:c25:c25:ddea:69a/1282c19:dd:dd0:ec00:c25:c25:ddea:69a
1562c19:dd:dd0:ec00:c25:c25:ddea:69b/1282c19:dd:dd0:ec00:c25:c25:ddea:69b
1572c19:dd:dd0:ec00:c25:c25:ddea:69c/1282c19:dd:dd0:ec00:c25:c25:ddea:69c
1582c19:dd:dd0:ec00:c25:c25:ddea:69d/1282c19:dd:dd0:ec00:c25:c25:ddea:69d
1592c19:dd:dd0:ec00:c25:c25:ddea:69e/1282c19:dd:dd0:ec00:c25:c25:ddea:69e
1602c19:dd:dd0:ec00:c25:c25:ddea:69f/1282c19:dd:dd0:ec00:c25:c25:ddea:69f
1612c19:dd:dd0:ec00:c25:c25:ddea:6a0/1282c19:dd:dd0:ec00:c25:c25:ddea:6a0
1622c19:dd:dd0:ec00:c25:c25:ddea:6a1/1282c19:dd:dd0:ec00:c25:c25:ddea:6a1
1632c19:dd:dd0:ec00:c25:c25:ddea:6a2/1282c19:dd:dd0:ec00:c25:c25:ddea:6a2
1642c19:dd:dd0:ec00:c25:c25:ddea:6a3/1282c19:dd:dd0:ec00:c25:c25:ddea:6a3
1652c19:dd:dd0:ec00:c25:c25:ddea:6a4/1282c19:dd:dd0:ec00:c25:c25:ddea:6a4
1662c19:dd:dd0:ec00:c25:c25:ddea:6a5/1282c19:dd:dd0:ec00:c25:c25:ddea:6a5
1672c19:dd:dd0:ec00:c25:c25:ddea:6a6/1282c19:dd:dd0:ec00:c25:c25:ddea:6a6
1682c19:dd:dd0:ec00:c25:c25:ddea:6a7/1282c19:dd:dd0:ec00:c25:c25:ddea:6a7
1692c19:dd:dd0:ec00:c25:c25:ddea:6a8/1282c19:dd:dd0:ec00:c25:c25:ddea:6a8
1702c19:dd:dd0:ec00:c25:c25:ddea:6a9/1282c19:dd:dd0:ec00:c25:c25:ddea:6a9
1712c19:dd:dd0:ec00:c25:c25:ddea:6aa/1282c19:dd:dd0:ec00:c25:c25:ddea:6aa
1722c19:dd:dd0:ec00:c25:c25:ddea:6ab/1282c19:dd:dd0:ec00:c25:c25:ddea:6ab
1732c19:dd:dd0:ec00:c25:c25:ddea:6ac/1282c19:dd:dd0:ec00:c25:c25:ddea:6ac
1742c19:dd:dd0:ec00:c25:c25:ddea:6ad/1282c19:dd:dd0:ec00:c25:c25:ddea:6ad
1752c19:dd:dd0:ec00:c25:c25:ddea:6ae/1282c19:dd:dd0:ec00:c25:c25:ddea:6ae
1762c19:dd:dd0:ec00:c25:c25:ddea:6af/1282c19:dd:dd0:ec00:c25:c25:ddea:6af
1772c19:dd:dd0:ec00:c25:c25:ddea:6b0/1282c19:dd:dd0:ec00:c25:c25:ddea:6b0
1782c19:dd:dd0:ec00:c25:c25:ddea:6b1/1282c19:dd:dd0:ec00:c25:c25:ddea:6b1
1792c19:dd:dd0:ec00:c25:c25:ddea:6b2/1282c19:dd:dd0:ec00:c25:c25:ddea:6b2
1802c19:dd:dd0:ec00:c25:c25:ddea:6b3/1282c19:dd:dd0:ec00:c25:c25:ddea:6b3
1812c19:dd:dd0:ec00:c25:c25:ddea:6b4/1282c19:dd:dd0:ec00:c25:c25:ddea:6b4
1822c19:dd:dd0:ec00:c25:c25:ddea:6b5/1282c19:dd:dd0:ec00:c25:c25:ddea:6b5
1832c19:dd:dd0:ec00:c25:c25:ddea:6b6/1282c19:dd:dd0:ec00:c25:c25:ddea:6b6
1842c19:dd:dd0:ec00:c25:c25:ddea:6b7/1282c19:dd:dd0:ec00:c25:c25:ddea:6b7
1852c19:dd:dd0:ec00:c25:c25:ddea:6b8/1282c19:dd:dd0:ec00:c25:c25:ddea:6b8
1862c19:dd:dd0:ec00:c25:c25:ddea:6b9/1282c19:dd:dd0:ec00:c25:c25:ddea:6b9
1872c19:dd:dd0:ec00:c25:c25:ddea:6ba/1282c19:dd:dd0:ec00:c25:c25:ddea:6ba
1882c19:dd:dd0:ec00:c25:c25:ddea:6bb/1282c19:dd:dd0:ec00:c25:c25:ddea:6bb
1892c19:dd:dd0:ec00:c25:c25:ddea:6bc/1282c19:dd:dd0:ec00:c25:c25:ddea:6bc
1902c19:dd:dd0:ec00:c25:c25:ddea:6bd/1282c19:dd:dd0:ec00:c25:c25:ddea:6bd
1912c19:dd:dd0:ec00:c25:c25:ddea:6be/1282c19:dd:dd0:ec00:c25:c25:ddea:6be
1922c19:dd:dd0:ec00:c25:c25:ddea:6bf/1282c19:dd:dd0:ec00:c25:c25:ddea:6bf
1932c19:dd:dd0:ec00:c25:c25:ddea:6c0/1282c19:dd:dd0:ec00:c25:c25:ddea:6c0
1942c19:dd:dd0:ec00:c25:c25:ddea:6c1/1282c19:dd:dd0:ec00:c25:c25:ddea:6c1
1952c19:dd:dd0:ec00:c25:c25:ddea:6c2/1282c19:dd:dd0:ec00:c25:c25:ddea:6c2
1962c19:dd:dd0:ec00:c25:c25:ddea:6c3/1282c19:dd:dd0:ec00:c25:c25:ddea:6c3
1972c19:dd:dd0:ec00:c25:c25:ddea:6c4/1282c19:dd:dd0:ec00:c25:c25:ddea:6c4
1982c19:dd:dd0:ec00:c25:c25:ddea:6c5/1282c19:dd:dd0:ec00:c25:c25:ddea:6c5
1992c19:dd:dd0:ec00:c25:c25:ddea:6c6/1282c19:dd:dd0:ec00:c25:c25:ddea:6c6
2002c19:dd:dd0:ec00:c25:c25:ddea:6c7/1282c19:dd:dd0:ec00:c25:c25:ddea:6c7
2012c19:dd:dd0:ec00:c25:c25:ddea:6c8/1282c19:dd:dd0:ec00:c25:c25:ddea:6c8
2022c19:dd:dd0:ec00:c25:c25:ddea:6c9/1282c19:dd:dd0:ec00:c25:c25:ddea:6c9
2032c19:dd:dd0:ec00:c25:c25:ddea:6ca/1282c19:dd:dd0:ec00:c25:c25:ddea:6ca
2042c19:dd:dd0:ec00:c25:c25:ddea:6cb/1282c19:dd:dd0:ec00:c25:c25:ddea:6cb
2052c19:dd:dd0:ec00:c25:c25:ddea:6cc/1282c19:dd:dd0:ec00:c25:c25:ddea:6cc
2062c19:dd:dd0:ec00:c25:c25:ddea:6cd/1282c19:dd:dd0:ec00:c25:c25:ddea:6cd
2072c19:dd:dd0:ec00:c25:c25:ddea:6ce/1282c19:dd:dd0:ec00:c25:c25:ddea:6ce
2082c19:dd:dd0:ec00:c25:c25:ddea:6cf/1282c19:dd:dd0:ec00:c25:c25:ddea:6cf
2092c19:dd:dd0:ec00:c25:c25:ddea:6d0/1282c19:dd:dd0:ec00:c25:c25:ddea:6d0
2102c19:dd:dd0:ec00:c25:c25:ddea:6d1/1282c19:dd:dd0:ec00:c25:c25:ddea:6d1
2112c19:dd:dd0:ec00:c25:c25:ddea:6d2/1282c19:dd:dd0:ec00:c25:c25:ddea:6d2
2122c19:dd:dd0:ec00:c25:c25:ddea:6d3/1282c19:dd:dd0:ec00:c25:c25:ddea:6d3
2132c19:dd:dd0:ec00:c25:c25:ddea:6d4/1282c19:dd:dd0:ec00:c25:c25:ddea:6d4
2142c19:dd:dd0:ec00:c25:c25:ddea:6d5/1282c19:dd:dd0:ec00:c25:c25:ddea:6d5
2152c19:dd:dd0:ec00:c25:c25:ddea:6d6/1282c19:dd:dd0:ec00:c25:c25:ddea:6d6
2162c19:dd:dd0:ec00:c25:c25:ddea:6d7/1282c19:dd:dd0:ec00:c25:c25:ddea:6d7
2172c19:dd:dd0:ec00:c25:c25:ddea:6d8/1282c19:dd:dd0:ec00:c25:c25:ddea:6d8
2182c19:dd:dd0:ec00:c25:c25:ddea:6d9/1282c19:dd:dd0:ec00:c25:c25:ddea:6d9
2192c19:dd:dd0:ec00:c25:c25:ddea:6da/1282c19:dd:dd0:ec00:c25:c25:ddea:6da
2202c19:dd:dd0:ec00:c25:c25:ddea:6db/1282c19:dd:dd0:ec00:c25:c25:ddea:6db
2212c19:dd:dd0:ec00:c25:c25:ddea:6dc/1282c19:dd:dd0:ec00:c25:c25:ddea:6dc
2222c19:dd:dd0:ec00:c25:c25:ddea:6dd/1282c19:dd:dd0:ec00:c25:c25:ddea:6dd
2232c19:dd:dd0:ec00:c25:c25:ddea:6de/1282c19:dd:dd0:ec00:c25:c25:ddea:6de
2242c19:dd:dd0:ec00:c25:c25:ddea:6df/1282c19:dd:dd0:ec00:c25:c25:ddea:6df
2252c19:dd:dd0:ec00:c25:c25:ddea:6e0/1282c19:dd:dd0:ec00:c25:c25:ddea:6e0
2262c19:dd:dd0:ec00:c25:c25:ddea:6e1/1282c19:dd:dd0:ec00:c25:c25:ddea:6e1
2272c19:dd:dd0:ec00:c25:c25:ddea:6e2/1282c19:dd:dd0:ec00:c25:c25:ddea:6e2
2282c19:dd:dd0:ec00:c25:c25:ddea:6e3/1282c19:dd:dd0:ec00:c25:c25:ddea:6e3
2292c19:dd:dd0:ec00:c25:c25:ddea:6e4/1282c19:dd:dd0:ec00:c25:c25:ddea:6e4
2302c19:dd:dd0:ec00:c25:c25:ddea:6e5/1282c19:dd:dd0:ec00:c25:c25:ddea:6e5
2312c19:dd:dd0:ec00:c25:c25:ddea:6e6/1282c19:dd:dd0:ec00:c25:c25:ddea:6e6
2322c19:dd:dd0:ec00:c25:c25:ddea:6e7/1282c19:dd:dd0:ec00:c25:c25:ddea:6e7
2332c19:dd:dd0:ec00:c25:c25:ddea:6e8/1282c19:dd:dd0:ec00:c25:c25:ddea:6e8
2342c19:dd:dd0:ec00:c25:c25:ddea:6e9/1282c19:dd:dd0:ec00:c25:c25:ddea:6e9
2352c19:dd:dd0:ec00:c25:c25:ddea:6ea/1282c19:dd:dd0:ec00:c25:c25:ddea:6ea
2362c19:dd:dd0:ec00:c25:c25:ddea:6eb/1282c19:dd:dd0:ec00:c25:c25:ddea:6eb
2372c19:dd:dd0:ec00:c25:c25:ddea:6ec/1282c19:dd:dd0:ec00:c25:c25:ddea:6ec
2382c19:dd:dd0:ec00:c25:c25:ddea:6ed/1282c19:dd:dd0:ec00:c25:c25:ddea:6ed
2392c19:dd:dd0:ec00:c25:c25:ddea:6ee/1282c19:dd:dd0:ec00:c25:c25:ddea:6ee
2402c19:dd:dd0:ec00:c25:c25:ddea:6ef/1282c19:dd:dd0:ec00:c25:c25:ddea:6ef
2412c19:dd:dd0:ec00:c25:c25:ddea:6f0/1282c19:dd:dd0:ec00:c25:c25:ddea:6f0
2422c19:dd:dd0:ec00:c25:c25:ddea:6f1/1282c19:dd:dd0:ec00:c25:c25:ddea:6f1
2432c19:dd:dd0:ec00:c25:c25:ddea:6f2/1282c19:dd:dd0:ec00:c25:c25:ddea:6f2
2442c19:dd:dd0:ec00:c25:c25:ddea:6f3/1282c19:dd:dd0:ec00:c25:c25:ddea:6f3
2452c19:dd:dd0:ec00:c25:c25:ddea:6f4/1282c19:dd:dd0:ec00:c25:c25:ddea:6f4
2462c19:dd:dd0:ec00:c25:c25:ddea:6f5/1282c19:dd:dd0:ec00:c25:c25:ddea:6f5
2472c19:dd:dd0:ec00:c25:c25:ddea:6f6/1282c19:dd:dd0:ec00:c25:c25:ddea:6f6
2482c19:dd:dd0:ec00:c25:c25:ddea:6f7/1282c19:dd:dd0:ec00:c25:c25:ddea:6f7
2492c19:dd:dd0:ec00:c25:c25:ddea:6f8/1282c19:dd:dd0:ec00:c25:c25:ddea:6f8
2502c19:dd:dd0:ec00:c25:c25:ddea:6f9/1282c19:dd:dd0:ec00:c25:c25:ddea:6f9
2512c19:dd:dd0:ec00:c25:c25:ddea:6fa/1282c19:dd:dd0:ec00:c25:c25:ddea:6fa
2522c19:dd:dd0:ec00:c25:c25:ddea:6fb/1282c19:dd:dd0:ec00:c25:c25:ddea:6fb
2532c19:dd:dd0:ec00:c25:c25:ddea:6fc/1282c19:dd:dd0:ec00:c25:c25:ddea:6fc
2542c19:dd:dd0:ec00:c25:c25:ddea:6fd/1282c19:dd:dd0:ec00:c25:c25:ddea:6fd
2552c19:dd:dd0:ec00:c25:c25:ddea:6fe/1282c19:dd:dd0:ec00:c25:c25:ddea:6fe
2562c19:dd:dd0:ec00:c25:c25:ddea:6ff/1282c19:dd:dd0:ec00:c25:c25:ddea:6ff

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.