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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:94de:6600/119
First address
2c19:dd:d9:dd:c25:c25:94de:6600
Last address
2c19:dd:d9:dd:c25:c25:94de:67ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:6600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
6.6.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
7.6.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
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/128
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:94de:6600/119 makes 512 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:6600/1282c19:dd:d9:dd:c25:c25:94de:6600
22c19:dd:d9:dd:c25:c25:94de:6601/1282c19:dd:d9:dd:c25:c25:94de:6601
32c19:dd:d9:dd:c25:c25:94de:6602/1282c19:dd:d9:dd:c25:c25:94de:6602
42c19:dd:d9:dd:c25:c25:94de:6603/1282c19:dd:d9:dd:c25:c25:94de:6603
52c19:dd:d9:dd:c25:c25:94de:6604/1282c19:dd:d9:dd:c25:c25:94de:6604
62c19:dd:d9:dd:c25:c25:94de:6605/1282c19:dd:d9:dd:c25:c25:94de:6605
72c19:dd:d9:dd:c25:c25:94de:6606/1282c19:dd:d9:dd:c25:c25:94de:6606
82c19:dd:d9:dd:c25:c25:94de:6607/1282c19:dd:d9:dd:c25:c25:94de:6607
92c19:dd:d9:dd:c25:c25:94de:6608/1282c19:dd:d9:dd:c25:c25:94de:6608
102c19:dd:d9:dd:c25:c25:94de:6609/1282c19:dd:d9:dd:c25:c25:94de:6609
112c19:dd:d9:dd:c25:c25:94de:660a/1282c19:dd:d9:dd:c25:c25:94de:660a
122c19:dd:d9:dd:c25:c25:94de:660b/1282c19:dd:d9:dd:c25:c25:94de:660b
132c19:dd:d9:dd:c25:c25:94de:660c/1282c19:dd:d9:dd:c25:c25:94de:660c
142c19:dd:d9:dd:c25:c25:94de:660d/1282c19:dd:d9:dd:c25:c25:94de:660d
152c19:dd:d9:dd:c25:c25:94de:660e/1282c19:dd:d9:dd:c25:c25:94de:660e
162c19:dd:d9:dd:c25:c25:94de:660f/1282c19:dd:d9:dd:c25:c25:94de:660f
172c19:dd:d9:dd:c25:c25:94de:6610/1282c19:dd:d9:dd:c25:c25:94de:6610
182c19:dd:d9:dd:c25:c25:94de:6611/1282c19:dd:d9:dd:c25:c25:94de:6611
192c19:dd:d9:dd:c25:c25:94de:6612/1282c19:dd:d9:dd:c25:c25:94de:6612
202c19:dd:d9:dd:c25:c25:94de:6613/1282c19:dd:d9:dd:c25:c25:94de:6613
212c19:dd:d9:dd:c25:c25:94de:6614/1282c19:dd:d9:dd:c25:c25:94de:6614
222c19:dd:d9:dd:c25:c25:94de:6615/1282c19:dd:d9:dd:c25:c25:94de:6615
232c19:dd:d9:dd:c25:c25:94de:6616/1282c19:dd:d9:dd:c25:c25:94de:6616
242c19:dd:d9:dd:c25:c25:94de:6617/1282c19:dd:d9:dd:c25:c25:94de:6617
252c19:dd:d9:dd:c25:c25:94de:6618/1282c19:dd:d9:dd:c25:c25:94de:6618
262c19:dd:d9:dd:c25:c25:94de:6619/1282c19:dd:d9:dd:c25:c25:94de:6619
272c19:dd:d9:dd:c25:c25:94de:661a/1282c19:dd:d9:dd:c25:c25:94de:661a
282c19:dd:d9:dd:c25:c25:94de:661b/1282c19:dd:d9:dd:c25:c25:94de:661b
292c19:dd:d9:dd:c25:c25:94de:661c/1282c19:dd:d9:dd:c25:c25:94de:661c
302c19:dd:d9:dd:c25:c25:94de:661d/1282c19:dd:d9:dd:c25:c25:94de:661d
312c19:dd:d9:dd:c25:c25:94de:661e/1282c19:dd:d9:dd:c25:c25:94de:661e
322c19:dd:d9:dd:c25:c25:94de:661f/1282c19:dd:d9:dd:c25:c25:94de:661f
332c19:dd:d9:dd:c25:c25:94de:6620/1282c19:dd:d9:dd:c25:c25:94de:6620
342c19:dd:d9:dd:c25:c25:94de:6621/1282c19:dd:d9:dd:c25:c25:94de:6621
352c19:dd:d9:dd:c25:c25:94de:6622/1282c19:dd:d9:dd:c25:c25:94de:6622
362c19:dd:d9:dd:c25:c25:94de:6623/1282c19:dd:d9:dd:c25:c25:94de:6623
372c19:dd:d9:dd:c25:c25:94de:6624/1282c19:dd:d9:dd:c25:c25:94de:6624
382c19:dd:d9:dd:c25:c25:94de:6625/1282c19:dd:d9:dd:c25:c25:94de:6625
392c19:dd:d9:dd:c25:c25:94de:6626/1282c19:dd:d9:dd:c25:c25:94de:6626
402c19:dd:d9:dd:c25:c25:94de:6627/1282c19:dd:d9:dd:c25:c25:94de:6627
412c19:dd:d9:dd:c25:c25:94de:6628/1282c19:dd:d9:dd:c25:c25:94de:6628
422c19:dd:d9:dd:c25:c25:94de:6629/1282c19:dd:d9:dd:c25:c25:94de:6629
432c19:dd:d9:dd:c25:c25:94de:662a/1282c19:dd:d9:dd:c25:c25:94de:662a
442c19:dd:d9:dd:c25:c25:94de:662b/1282c19:dd:d9:dd:c25:c25:94de:662b
452c19:dd:d9:dd:c25:c25:94de:662c/1282c19:dd:d9:dd:c25:c25:94de:662c
462c19:dd:d9:dd:c25:c25:94de:662d/1282c19:dd:d9:dd:c25:c25:94de:662d
472c19:dd:d9:dd:c25:c25:94de:662e/1282c19:dd:d9:dd:c25:c25:94de:662e
482c19:dd:d9:dd:c25:c25:94de:662f/1282c19:dd:d9:dd:c25:c25:94de:662f
492c19:dd:d9:dd:c25:c25:94de:6630/1282c19:dd:d9:dd:c25:c25:94de:6630
502c19:dd:d9:dd:c25:c25:94de:6631/1282c19:dd:d9:dd:c25:c25:94de:6631
512c19:dd:d9:dd:c25:c25:94de:6632/1282c19:dd:d9:dd:c25:c25:94de:6632
522c19:dd:d9:dd:c25:c25:94de:6633/1282c19:dd:d9:dd:c25:c25:94de:6633
532c19:dd:d9:dd:c25:c25:94de:6634/1282c19:dd:d9:dd:c25:c25:94de:6634
542c19:dd:d9:dd:c25:c25:94de:6635/1282c19:dd:d9:dd:c25:c25:94de:6635
552c19:dd:d9:dd:c25:c25:94de:6636/1282c19:dd:d9:dd:c25:c25:94de:6636
562c19:dd:d9:dd:c25:c25:94de:6637/1282c19:dd:d9:dd:c25:c25:94de:6637
572c19:dd:d9:dd:c25:c25:94de:6638/1282c19:dd:d9:dd:c25:c25:94de:6638
582c19:dd:d9:dd:c25:c25:94de:6639/1282c19:dd:d9:dd:c25:c25:94de:6639
592c19:dd:d9:dd:c25:c25:94de:663a/1282c19:dd:d9:dd:c25:c25:94de:663a
602c19:dd:d9:dd:c25:c25:94de:663b/1282c19:dd:d9:dd:c25:c25:94de:663b
612c19:dd:d9:dd:c25:c25:94de:663c/1282c19:dd:d9:dd:c25:c25:94de:663c
622c19:dd:d9:dd:c25:c25:94de:663d/1282c19:dd:d9:dd:c25:c25:94de:663d
632c19:dd:d9:dd:c25:c25:94de:663e/1282c19:dd:d9:dd:c25:c25:94de:663e
642c19:dd:d9:dd:c25:c25:94de:663f/1282c19:dd:d9:dd:c25:c25:94de:663f
652c19:dd:d9:dd:c25:c25:94de:6640/1282c19:dd:d9:dd:c25:c25:94de:6640
662c19:dd:d9:dd:c25:c25:94de:6641/1282c19:dd:d9:dd:c25:c25:94de:6641
672c19:dd:d9:dd:c25:c25:94de:6642/1282c19:dd:d9:dd:c25:c25:94de:6642
682c19:dd:d9:dd:c25:c25:94de:6643/1282c19:dd:d9:dd:c25:c25:94de:6643
692c19:dd:d9:dd:c25:c25:94de:6644/1282c19:dd:d9:dd:c25:c25:94de:6644
702c19:dd:d9:dd:c25:c25:94de:6645/1282c19:dd:d9:dd:c25:c25:94de:6645
712c19:dd:d9:dd:c25:c25:94de:6646/1282c19:dd:d9:dd:c25:c25:94de:6646
722c19:dd:d9:dd:c25:c25:94de:6647/1282c19:dd:d9:dd:c25:c25:94de:6647
732c19:dd:d9:dd:c25:c25:94de:6648/1282c19:dd:d9:dd:c25:c25:94de:6648
742c19:dd:d9:dd:c25:c25:94de:6649/1282c19:dd:d9:dd:c25:c25:94de:6649
752c19:dd:d9:dd:c25:c25:94de:664a/1282c19:dd:d9:dd:c25:c25:94de:664a
762c19:dd:d9:dd:c25:c25:94de:664b/1282c19:dd:d9:dd:c25:c25:94de:664b
772c19:dd:d9:dd:c25:c25:94de:664c/1282c19:dd:d9:dd:c25:c25:94de:664c
782c19:dd:d9:dd:c25:c25:94de:664d/1282c19:dd:d9:dd:c25:c25:94de:664d
792c19:dd:d9:dd:c25:c25:94de:664e/1282c19:dd:d9:dd:c25:c25:94de:664e
802c19:dd:d9:dd:c25:c25:94de:664f/1282c19:dd:d9:dd:c25:c25:94de:664f
812c19:dd:d9:dd:c25:c25:94de:6650/1282c19:dd:d9:dd:c25:c25:94de:6650
822c19:dd:d9:dd:c25:c25:94de:6651/1282c19:dd:d9:dd:c25:c25:94de:6651
832c19:dd:d9:dd:c25:c25:94de:6652/1282c19:dd:d9:dd:c25:c25:94de:6652
842c19:dd:d9:dd:c25:c25:94de:6653/1282c19:dd:d9:dd:c25:c25:94de:6653
852c19:dd:d9:dd:c25:c25:94de:6654/1282c19:dd:d9:dd:c25:c25:94de:6654
862c19:dd:d9:dd:c25:c25:94de:6655/1282c19:dd:d9:dd:c25:c25:94de:6655
872c19:dd:d9:dd:c25:c25:94de:6656/1282c19:dd:d9:dd:c25:c25:94de:6656
882c19:dd:d9:dd:c25:c25:94de:6657/1282c19:dd:d9:dd:c25:c25:94de:6657
892c19:dd:d9:dd:c25:c25:94de:6658/1282c19:dd:d9:dd:c25:c25:94de:6658
902c19:dd:d9:dd:c25:c25:94de:6659/1282c19:dd:d9:dd:c25:c25:94de:6659
912c19:dd:d9:dd:c25:c25:94de:665a/1282c19:dd:d9:dd:c25:c25:94de:665a
922c19:dd:d9:dd:c25:c25:94de:665b/1282c19:dd:d9:dd:c25:c25:94de:665b
932c19:dd:d9:dd:c25:c25:94de:665c/1282c19:dd:d9:dd:c25:c25:94de:665c
942c19:dd:d9:dd:c25:c25:94de:665d/1282c19:dd:d9:dd:c25:c25:94de:665d
952c19:dd:d9:dd:c25:c25:94de:665e/1282c19:dd:d9:dd:c25:c25:94de:665e
962c19:dd:d9:dd:c25:c25:94de:665f/1282c19:dd:d9:dd:c25:c25:94de:665f
972c19:dd:d9:dd:c25:c25:94de:6660/1282c19:dd:d9:dd:c25:c25:94de:6660
982c19:dd:d9:dd:c25:c25:94de:6661/1282c19:dd:d9:dd:c25:c25:94de:6661
992c19:dd:d9:dd:c25:c25:94de:6662/1282c19:dd:d9:dd:c25:c25:94de:6662
1002c19:dd:d9:dd:c25:c25:94de:6663/1282c19:dd:d9:dd:c25:c25:94de:6663
1012c19:dd:d9:dd:c25:c25:94de:6664/1282c19:dd:d9:dd:c25:c25:94de:6664
1022c19:dd:d9:dd:c25:c25:94de:6665/1282c19:dd:d9:dd:c25:c25:94de:6665
1032c19:dd:d9:dd:c25:c25:94de:6666/1282c19:dd:d9:dd:c25:c25:94de:6666
1042c19:dd:d9:dd:c25:c25:94de:6667/1282c19:dd:d9:dd:c25:c25:94de:6667
1052c19:dd:d9:dd:c25:c25:94de:6668/1282c19:dd:d9:dd:c25:c25:94de:6668
1062c19:dd:d9:dd:c25:c25:94de:6669/1282c19:dd:d9:dd:c25:c25:94de:6669
1072c19:dd:d9:dd:c25:c25:94de:666a/1282c19:dd:d9:dd:c25:c25:94de:666a
1082c19:dd:d9:dd:c25:c25:94de:666b/1282c19:dd:d9:dd:c25:c25:94de:666b
1092c19:dd:d9:dd:c25:c25:94de:666c/1282c19:dd:d9:dd:c25:c25:94de:666c
1102c19:dd:d9:dd:c25:c25:94de:666d/1282c19:dd:d9:dd:c25:c25:94de:666d
1112c19:dd:d9:dd:c25:c25:94de:666e/1282c19:dd:d9:dd:c25:c25:94de:666e
1122c19:dd:d9:dd:c25:c25:94de:666f/1282c19:dd:d9:dd:c25:c25:94de:666f
1132c19:dd:d9:dd:c25:c25:94de:6670/1282c19:dd:d9:dd:c25:c25:94de:6670
1142c19:dd:d9:dd:c25:c25:94de:6671/1282c19:dd:d9:dd:c25:c25:94de:6671
1152c19:dd:d9:dd:c25:c25:94de:6672/1282c19:dd:d9:dd:c25:c25:94de:6672
1162c19:dd:d9:dd:c25:c25:94de:6673/1282c19:dd:d9:dd:c25:c25:94de:6673
1172c19:dd:d9:dd:c25:c25:94de:6674/1282c19:dd:d9:dd:c25:c25:94de:6674
1182c19:dd:d9:dd:c25:c25:94de:6675/1282c19:dd:d9:dd:c25:c25:94de:6675
1192c19:dd:d9:dd:c25:c25:94de:6676/1282c19:dd:d9:dd:c25:c25:94de:6676
1202c19:dd:d9:dd:c25:c25:94de:6677/1282c19:dd:d9:dd:c25:c25:94de:6677
1212c19:dd:d9:dd:c25:c25:94de:6678/1282c19:dd:d9:dd:c25:c25:94de:6678
1222c19:dd:d9:dd:c25:c25:94de:6679/1282c19:dd:d9:dd:c25:c25:94de:6679
1232c19:dd:d9:dd:c25:c25:94de:667a/1282c19:dd:d9:dd:c25:c25:94de:667a
1242c19:dd:d9:dd:c25:c25:94de:667b/1282c19:dd:d9:dd:c25:c25:94de:667b
1252c19:dd:d9:dd:c25:c25:94de:667c/1282c19:dd:d9:dd:c25:c25:94de:667c
1262c19:dd:d9:dd:c25:c25:94de:667d/1282c19:dd:d9:dd:c25:c25:94de:667d
1272c19:dd:d9:dd:c25:c25:94de:667e/1282c19:dd:d9:dd:c25:c25:94de:667e
1282c19:dd:d9:dd:c25:c25:94de:667f/1282c19:dd:d9:dd:c25:c25:94de:667f
1292c19:dd:d9:dd:c25:c25:94de:6680/1282c19:dd:d9:dd:c25:c25:94de:6680
1302c19:dd:d9:dd:c25:c25:94de:6681/1282c19:dd:d9:dd:c25:c25:94de:6681
1312c19:dd:d9:dd:c25:c25:94de:6682/1282c19:dd:d9:dd:c25:c25:94de:6682
1322c19:dd:d9:dd:c25:c25:94de:6683/1282c19:dd:d9:dd:c25:c25:94de:6683
1332c19:dd:d9:dd:c25:c25:94de:6684/1282c19:dd:d9:dd:c25:c25:94de:6684
1342c19:dd:d9:dd:c25:c25:94de:6685/1282c19:dd:d9:dd:c25:c25:94de:6685
1352c19:dd:d9:dd:c25:c25:94de:6686/1282c19:dd:d9:dd:c25:c25:94de:6686
1362c19:dd:d9:dd:c25:c25:94de:6687/1282c19:dd:d9:dd:c25:c25:94de:6687
1372c19:dd:d9:dd:c25:c25:94de:6688/1282c19:dd:d9:dd:c25:c25:94de:6688
1382c19:dd:d9:dd:c25:c25:94de:6689/1282c19:dd:d9:dd:c25:c25:94de:6689
1392c19:dd:d9:dd:c25:c25:94de:668a/1282c19:dd:d9:dd:c25:c25:94de:668a
1402c19:dd:d9:dd:c25:c25:94de:668b/1282c19:dd:d9:dd:c25:c25:94de:668b
1412c19:dd:d9:dd:c25:c25:94de:668c/1282c19:dd:d9:dd:c25:c25:94de:668c
1422c19:dd:d9:dd:c25:c25:94de:668d/1282c19:dd:d9:dd:c25:c25:94de:668d
1432c19:dd:d9:dd:c25:c25:94de:668e/1282c19:dd:d9:dd:c25:c25:94de:668e
1442c19:dd:d9:dd:c25:c25:94de:668f/1282c19:dd:d9:dd:c25:c25:94de:668f
1452c19:dd:d9:dd:c25:c25:94de:6690/1282c19:dd:d9:dd:c25:c25:94de:6690
1462c19:dd:d9:dd:c25:c25:94de:6691/1282c19:dd:d9:dd:c25:c25:94de:6691
1472c19:dd:d9:dd:c25:c25:94de:6692/1282c19:dd:d9:dd:c25:c25:94de:6692
1482c19:dd:d9:dd:c25:c25:94de:6693/1282c19:dd:d9:dd:c25:c25:94de:6693
1492c19:dd:d9:dd:c25:c25:94de:6694/1282c19:dd:d9:dd:c25:c25:94de:6694
1502c19:dd:d9:dd:c25:c25:94de:6695/1282c19:dd:d9:dd:c25:c25:94de:6695
1512c19:dd:d9:dd:c25:c25:94de:6696/1282c19:dd:d9:dd:c25:c25:94de:6696
1522c19:dd:d9:dd:c25:c25:94de:6697/1282c19:dd:d9:dd:c25:c25:94de:6697
1532c19:dd:d9:dd:c25:c25:94de:6698/1282c19:dd:d9:dd:c25:c25:94de:6698
1542c19:dd:d9:dd:c25:c25:94de:6699/1282c19:dd:d9:dd:c25:c25:94de:6699
1552c19:dd:d9:dd:c25:c25:94de:669a/1282c19:dd:d9:dd:c25:c25:94de:669a
1562c19:dd:d9:dd:c25:c25:94de:669b/1282c19:dd:d9:dd:c25:c25:94de:669b
1572c19:dd:d9:dd:c25:c25:94de:669c/1282c19:dd:d9:dd:c25:c25:94de:669c
1582c19:dd:d9:dd:c25:c25:94de:669d/1282c19:dd:d9:dd:c25:c25:94de:669d
1592c19:dd:d9:dd:c25:c25:94de:669e/1282c19:dd:d9:dd:c25:c25:94de:669e
1602c19:dd:d9:dd:c25:c25:94de:669f/1282c19:dd:d9:dd:c25:c25:94de:669f
1612c19:dd:d9:dd:c25:c25:94de:66a0/1282c19:dd:d9:dd:c25:c25:94de:66a0
1622c19:dd:d9:dd:c25:c25:94de:66a1/1282c19:dd:d9:dd:c25:c25:94de:66a1
1632c19:dd:d9:dd:c25:c25:94de:66a2/1282c19:dd:d9:dd:c25:c25:94de:66a2
1642c19:dd:d9:dd:c25:c25:94de:66a3/1282c19:dd:d9:dd:c25:c25:94de:66a3
1652c19:dd:d9:dd:c25:c25:94de:66a4/1282c19:dd:d9:dd:c25:c25:94de:66a4
1662c19:dd:d9:dd:c25:c25:94de:66a5/1282c19:dd:d9:dd:c25:c25:94de:66a5
1672c19:dd:d9:dd:c25:c25:94de:66a6/1282c19:dd:d9:dd:c25:c25:94de:66a6
1682c19:dd:d9:dd:c25:c25:94de:66a7/1282c19:dd:d9:dd:c25:c25:94de:66a7
1692c19:dd:d9:dd:c25:c25:94de:66a8/1282c19:dd:d9:dd:c25:c25:94de:66a8
1702c19:dd:d9:dd:c25:c25:94de:66a9/1282c19:dd:d9:dd:c25:c25:94de:66a9
1712c19:dd:d9:dd:c25:c25:94de:66aa/1282c19:dd:d9:dd:c25:c25:94de:66aa
1722c19:dd:d9:dd:c25:c25:94de:66ab/1282c19:dd:d9:dd:c25:c25:94de:66ab
1732c19:dd:d9:dd:c25:c25:94de:66ac/1282c19:dd:d9:dd:c25:c25:94de:66ac
1742c19:dd:d9:dd:c25:c25:94de:66ad/1282c19:dd:d9:dd:c25:c25:94de:66ad
1752c19:dd:d9:dd:c25:c25:94de:66ae/1282c19:dd:d9:dd:c25:c25:94de:66ae
1762c19:dd:d9:dd:c25:c25:94de:66af/1282c19:dd:d9:dd:c25:c25:94de:66af
1772c19:dd:d9:dd:c25:c25:94de:66b0/1282c19:dd:d9:dd:c25:c25:94de:66b0
1782c19:dd:d9:dd:c25:c25:94de:66b1/1282c19:dd:d9:dd:c25:c25:94de:66b1
1792c19:dd:d9:dd:c25:c25:94de:66b2/1282c19:dd:d9:dd:c25:c25:94de:66b2
1802c19:dd:d9:dd:c25:c25:94de:66b3/1282c19:dd:d9:dd:c25:c25:94de:66b3
1812c19:dd:d9:dd:c25:c25:94de:66b4/1282c19:dd:d9:dd:c25:c25:94de:66b4
1822c19:dd:d9:dd:c25:c25:94de:66b5/1282c19:dd:d9:dd:c25:c25:94de:66b5
1832c19:dd:d9:dd:c25:c25:94de:66b6/1282c19:dd:d9:dd:c25:c25:94de:66b6
1842c19:dd:d9:dd:c25:c25:94de:66b7/1282c19:dd:d9:dd:c25:c25:94de:66b7
1852c19:dd:d9:dd:c25:c25:94de:66b8/1282c19:dd:d9:dd:c25:c25:94de:66b8
1862c19:dd:d9:dd:c25:c25:94de:66b9/1282c19:dd:d9:dd:c25:c25:94de:66b9
1872c19:dd:d9:dd:c25:c25:94de:66ba/1282c19:dd:d9:dd:c25:c25:94de:66ba
1882c19:dd:d9:dd:c25:c25:94de:66bb/1282c19:dd:d9:dd:c25:c25:94de:66bb
1892c19:dd:d9:dd:c25:c25:94de:66bc/1282c19:dd:d9:dd:c25:c25:94de:66bc
1902c19:dd:d9:dd:c25:c25:94de:66bd/1282c19:dd:d9:dd:c25:c25:94de:66bd
1912c19:dd:d9:dd:c25:c25:94de:66be/1282c19:dd:d9:dd:c25:c25:94de:66be
1922c19:dd:d9:dd:c25:c25:94de:66bf/1282c19:dd:d9:dd:c25:c25:94de:66bf
1932c19:dd:d9:dd:c25:c25:94de:66c0/1282c19:dd:d9:dd:c25:c25:94de:66c0
1942c19:dd:d9:dd:c25:c25:94de:66c1/1282c19:dd:d9:dd:c25:c25:94de:66c1
1952c19:dd:d9:dd:c25:c25:94de:66c2/1282c19:dd:d9:dd:c25:c25:94de:66c2
1962c19:dd:d9:dd:c25:c25:94de:66c3/1282c19:dd:d9:dd:c25:c25:94de:66c3
1972c19:dd:d9:dd:c25:c25:94de:66c4/1282c19:dd:d9:dd:c25:c25:94de:66c4
1982c19:dd:d9:dd:c25:c25:94de:66c5/1282c19:dd:d9:dd:c25:c25:94de:66c5
1992c19:dd:d9:dd:c25:c25:94de:66c6/1282c19:dd:d9:dd:c25:c25:94de:66c6
2002c19:dd:d9:dd:c25:c25:94de:66c7/1282c19:dd:d9:dd:c25:c25:94de:66c7
2012c19:dd:d9:dd:c25:c25:94de:66c8/1282c19:dd:d9:dd:c25:c25:94de:66c8
2022c19:dd:d9:dd:c25:c25:94de:66c9/1282c19:dd:d9:dd:c25:c25:94de:66c9
2032c19:dd:d9:dd:c25:c25:94de:66ca/1282c19:dd:d9:dd:c25:c25:94de:66ca
2042c19:dd:d9:dd:c25:c25:94de:66cb/1282c19:dd:d9:dd:c25:c25:94de:66cb
2052c19:dd:d9:dd:c25:c25:94de:66cc/1282c19:dd:d9:dd:c25:c25:94de:66cc
2062c19:dd:d9:dd:c25:c25:94de:66cd/1282c19:dd:d9:dd:c25:c25:94de:66cd
2072c19:dd:d9:dd:c25:c25:94de:66ce/1282c19:dd:d9:dd:c25:c25:94de:66ce
2082c19:dd:d9:dd:c25:c25:94de:66cf/1282c19:dd:d9:dd:c25:c25:94de:66cf
2092c19:dd:d9:dd:c25:c25:94de:66d0/1282c19:dd:d9:dd:c25:c25:94de:66d0
2102c19:dd:d9:dd:c25:c25:94de:66d1/1282c19:dd:d9:dd:c25:c25:94de:66d1
2112c19:dd:d9:dd:c25:c25:94de:66d2/1282c19:dd:d9:dd:c25:c25:94de:66d2
2122c19:dd:d9:dd:c25:c25:94de:66d3/1282c19:dd:d9:dd:c25:c25:94de:66d3
2132c19:dd:d9:dd:c25:c25:94de:66d4/1282c19:dd:d9:dd:c25:c25:94de:66d4
2142c19:dd:d9:dd:c25:c25:94de:66d5/1282c19:dd:d9:dd:c25:c25:94de:66d5
2152c19:dd:d9:dd:c25:c25:94de:66d6/1282c19:dd:d9:dd:c25:c25:94de:66d6
2162c19:dd:d9:dd:c25:c25:94de:66d7/1282c19:dd:d9:dd:c25:c25:94de:66d7
2172c19:dd:d9:dd:c25:c25:94de:66d8/1282c19:dd:d9:dd:c25:c25:94de:66d8
2182c19:dd:d9:dd:c25:c25:94de:66d9/1282c19:dd:d9:dd:c25:c25:94de:66d9
2192c19:dd:d9:dd:c25:c25:94de:66da/1282c19:dd:d9:dd:c25:c25:94de:66da
2202c19:dd:d9:dd:c25:c25:94de:66db/1282c19:dd:d9:dd:c25:c25:94de:66db
2212c19:dd:d9:dd:c25:c25:94de:66dc/1282c19:dd:d9:dd:c25:c25:94de:66dc
2222c19:dd:d9:dd:c25:c25:94de:66dd/1282c19:dd:d9:dd:c25:c25:94de:66dd
2232c19:dd:d9:dd:c25:c25:94de:66de/1282c19:dd:d9:dd:c25:c25:94de:66de
2242c19:dd:d9:dd:c25:c25:94de:66df/1282c19:dd:d9:dd:c25:c25:94de:66df
2252c19:dd:d9:dd:c25:c25:94de:66e0/1282c19:dd:d9:dd:c25:c25:94de:66e0
2262c19:dd:d9:dd:c25:c25:94de:66e1/1282c19:dd:d9:dd:c25:c25:94de:66e1
2272c19:dd:d9:dd:c25:c25:94de:66e2/1282c19:dd:d9:dd:c25:c25:94de:66e2
2282c19:dd:d9:dd:c25:c25:94de:66e3/1282c19:dd:d9:dd:c25:c25:94de:66e3
2292c19:dd:d9:dd:c25:c25:94de:66e4/1282c19:dd:d9:dd:c25:c25:94de:66e4
2302c19:dd:d9:dd:c25:c25:94de:66e5/1282c19:dd:d9:dd:c25:c25:94de:66e5
2312c19:dd:d9:dd:c25:c25:94de:66e6/1282c19:dd:d9:dd:c25:c25:94de:66e6
2322c19:dd:d9:dd:c25:c25:94de:66e7/1282c19:dd:d9:dd:c25:c25:94de:66e7
2332c19:dd:d9:dd:c25:c25:94de:66e8/1282c19:dd:d9:dd:c25:c25:94de:66e8
2342c19:dd:d9:dd:c25:c25:94de:66e9/1282c19:dd:d9:dd:c25:c25:94de:66e9
2352c19:dd:d9:dd:c25:c25:94de:66ea/1282c19:dd:d9:dd:c25:c25:94de:66ea
2362c19:dd:d9:dd:c25:c25:94de:66eb/1282c19:dd:d9:dd:c25:c25:94de:66eb
2372c19:dd:d9:dd:c25:c25:94de:66ec/1282c19:dd:d9:dd:c25:c25:94de:66ec
2382c19:dd:d9:dd:c25:c25:94de:66ed/1282c19:dd:d9:dd:c25:c25:94de:66ed
2392c19:dd:d9:dd:c25:c25:94de:66ee/1282c19:dd:d9:dd:c25:c25:94de:66ee
2402c19:dd:d9:dd:c25:c25:94de:66ef/1282c19:dd:d9:dd:c25:c25:94de:66ef
2412c19:dd:d9:dd:c25:c25:94de:66f0/1282c19:dd:d9:dd:c25:c25:94de:66f0
2422c19:dd:d9:dd:c25:c25:94de:66f1/1282c19:dd:d9:dd:c25:c25:94de:66f1
2432c19:dd:d9:dd:c25:c25:94de:66f2/1282c19:dd:d9:dd:c25:c25:94de:66f2
2442c19:dd:d9:dd:c25:c25:94de:66f3/1282c19:dd:d9:dd:c25:c25:94de:66f3
2452c19:dd:d9:dd:c25:c25:94de:66f4/1282c19:dd:d9:dd:c25:c25:94de:66f4
2462c19:dd:d9:dd:c25:c25:94de:66f5/1282c19:dd:d9:dd:c25:c25:94de:66f5
2472c19:dd:d9:dd:c25:c25:94de:66f6/1282c19:dd:d9:dd:c25:c25:94de:66f6
2482c19:dd:d9:dd:c25:c25:94de:66f7/1282c19:dd:d9:dd:c25:c25:94de:66f7
2492c19:dd:d9:dd:c25:c25:94de:66f8/1282c19:dd:d9:dd:c25:c25:94de:66f8
2502c19:dd:d9:dd:c25:c25:94de:66f9/1282c19:dd:d9:dd:c25:c25:94de:66f9
2512c19:dd:d9:dd:c25:c25:94de:66fa/1282c19:dd:d9:dd:c25:c25:94de:66fa
2522c19:dd:d9:dd:c25:c25:94de:66fb/1282c19:dd:d9:dd:c25:c25:94de:66fb
2532c19:dd:d9:dd:c25:c25:94de:66fc/1282c19:dd:d9:dd:c25:c25:94de:66fc
2542c19:dd:d9:dd:c25:c25:94de:66fd/1282c19:dd:d9:dd:c25:c25:94de:66fd
2552c19:dd:d9:dd:c25:c25:94de:66fe/1282c19:dd:d9:dd:c25:c25:94de:66fe
2562c19:dd:d9:dd:c25:c25:94de:66ff/1282c19:dd:d9:dd:c25:c25:94de:66ff

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.