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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:d915:b600/120
First address
2c19:dd:d9:dd:c25:c25:d915:b600
Last address
2c19:dd:d9:dd:c25:c25:d915:b6ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:b600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.b.5.1.9.d.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:d915:b600/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:b600/1282c19:dd:d9:dd:c25:c25:d915:b600
22c19:dd:d9:dd:c25:c25:d915:b601/1282c19:dd:d9:dd:c25:c25:d915:b601
32c19:dd:d9:dd:c25:c25:d915:b602/1282c19:dd:d9:dd:c25:c25:d915:b602
42c19:dd:d9:dd:c25:c25:d915:b603/1282c19:dd:d9:dd:c25:c25:d915:b603
52c19:dd:d9:dd:c25:c25:d915:b604/1282c19:dd:d9:dd:c25:c25:d915:b604
62c19:dd:d9:dd:c25:c25:d915:b605/1282c19:dd:d9:dd:c25:c25:d915:b605
72c19:dd:d9:dd:c25:c25:d915:b606/1282c19:dd:d9:dd:c25:c25:d915:b606
82c19:dd:d9:dd:c25:c25:d915:b607/1282c19:dd:d9:dd:c25:c25:d915:b607
92c19:dd:d9:dd:c25:c25:d915:b608/1282c19:dd:d9:dd:c25:c25:d915:b608
102c19:dd:d9:dd:c25:c25:d915:b609/1282c19:dd:d9:dd:c25:c25:d915:b609
112c19:dd:d9:dd:c25:c25:d915:b60a/1282c19:dd:d9:dd:c25:c25:d915:b60a
122c19:dd:d9:dd:c25:c25:d915:b60b/1282c19:dd:d9:dd:c25:c25:d915:b60b
132c19:dd:d9:dd:c25:c25:d915:b60c/1282c19:dd:d9:dd:c25:c25:d915:b60c
142c19:dd:d9:dd:c25:c25:d915:b60d/1282c19:dd:d9:dd:c25:c25:d915:b60d
152c19:dd:d9:dd:c25:c25:d915:b60e/1282c19:dd:d9:dd:c25:c25:d915:b60e
162c19:dd:d9:dd:c25:c25:d915:b60f/1282c19:dd:d9:dd:c25:c25:d915:b60f
172c19:dd:d9:dd:c25:c25:d915:b610/1282c19:dd:d9:dd:c25:c25:d915:b610
182c19:dd:d9:dd:c25:c25:d915:b611/1282c19:dd:d9:dd:c25:c25:d915:b611
192c19:dd:d9:dd:c25:c25:d915:b612/1282c19:dd:d9:dd:c25:c25:d915:b612
202c19:dd:d9:dd:c25:c25:d915:b613/1282c19:dd:d9:dd:c25:c25:d915:b613
212c19:dd:d9:dd:c25:c25:d915:b614/1282c19:dd:d9:dd:c25:c25:d915:b614
222c19:dd:d9:dd:c25:c25:d915:b615/1282c19:dd:d9:dd:c25:c25:d915:b615
232c19:dd:d9:dd:c25:c25:d915:b616/1282c19:dd:d9:dd:c25:c25:d915:b616
242c19:dd:d9:dd:c25:c25:d915:b617/1282c19:dd:d9:dd:c25:c25:d915:b617
252c19:dd:d9:dd:c25:c25:d915:b618/1282c19:dd:d9:dd:c25:c25:d915:b618
262c19:dd:d9:dd:c25:c25:d915:b619/1282c19:dd:d9:dd:c25:c25:d915:b619
272c19:dd:d9:dd:c25:c25:d915:b61a/1282c19:dd:d9:dd:c25:c25:d915:b61a
282c19:dd:d9:dd:c25:c25:d915:b61b/1282c19:dd:d9:dd:c25:c25:d915:b61b
292c19:dd:d9:dd:c25:c25:d915:b61c/1282c19:dd:d9:dd:c25:c25:d915:b61c
302c19:dd:d9:dd:c25:c25:d915:b61d/1282c19:dd:d9:dd:c25:c25:d915:b61d
312c19:dd:d9:dd:c25:c25:d915:b61e/1282c19:dd:d9:dd:c25:c25:d915:b61e
322c19:dd:d9:dd:c25:c25:d915:b61f/1282c19:dd:d9:dd:c25:c25:d915:b61f
332c19:dd:d9:dd:c25:c25:d915:b620/1282c19:dd:d9:dd:c25:c25:d915:b620
342c19:dd:d9:dd:c25:c25:d915:b621/1282c19:dd:d9:dd:c25:c25:d915:b621
352c19:dd:d9:dd:c25:c25:d915:b622/1282c19:dd:d9:dd:c25:c25:d915:b622
362c19:dd:d9:dd:c25:c25:d915:b623/1282c19:dd:d9:dd:c25:c25:d915:b623
372c19:dd:d9:dd:c25:c25:d915:b624/1282c19:dd:d9:dd:c25:c25:d915:b624
382c19:dd:d9:dd:c25:c25:d915:b625/1282c19:dd:d9:dd:c25:c25:d915:b625
392c19:dd:d9:dd:c25:c25:d915:b626/1282c19:dd:d9:dd:c25:c25:d915:b626
402c19:dd:d9:dd:c25:c25:d915:b627/1282c19:dd:d9:dd:c25:c25:d915:b627
412c19:dd:d9:dd:c25:c25:d915:b628/1282c19:dd:d9:dd:c25:c25:d915:b628
422c19:dd:d9:dd:c25:c25:d915:b629/1282c19:dd:d9:dd:c25:c25:d915:b629
432c19:dd:d9:dd:c25:c25:d915:b62a/1282c19:dd:d9:dd:c25:c25:d915:b62a
442c19:dd:d9:dd:c25:c25:d915:b62b/1282c19:dd:d9:dd:c25:c25:d915:b62b
452c19:dd:d9:dd:c25:c25:d915:b62c/1282c19:dd:d9:dd:c25:c25:d915:b62c
462c19:dd:d9:dd:c25:c25:d915:b62d/1282c19:dd:d9:dd:c25:c25:d915:b62d
472c19:dd:d9:dd:c25:c25:d915:b62e/1282c19:dd:d9:dd:c25:c25:d915:b62e
482c19:dd:d9:dd:c25:c25:d915:b62f/1282c19:dd:d9:dd:c25:c25:d915:b62f
492c19:dd:d9:dd:c25:c25:d915:b630/1282c19:dd:d9:dd:c25:c25:d915:b630
502c19:dd:d9:dd:c25:c25:d915:b631/1282c19:dd:d9:dd:c25:c25:d915:b631
512c19:dd:d9:dd:c25:c25:d915:b632/1282c19:dd:d9:dd:c25:c25:d915:b632
522c19:dd:d9:dd:c25:c25:d915:b633/1282c19:dd:d9:dd:c25:c25:d915:b633
532c19:dd:d9:dd:c25:c25:d915:b634/1282c19:dd:d9:dd:c25:c25:d915:b634
542c19:dd:d9:dd:c25:c25:d915:b635/1282c19:dd:d9:dd:c25:c25:d915:b635
552c19:dd:d9:dd:c25:c25:d915:b636/1282c19:dd:d9:dd:c25:c25:d915:b636
562c19:dd:d9:dd:c25:c25:d915:b637/1282c19:dd:d9:dd:c25:c25:d915:b637
572c19:dd:d9:dd:c25:c25:d915:b638/1282c19:dd:d9:dd:c25:c25:d915:b638
582c19:dd:d9:dd:c25:c25:d915:b639/1282c19:dd:d9:dd:c25:c25:d915:b639
592c19:dd:d9:dd:c25:c25:d915:b63a/1282c19:dd:d9:dd:c25:c25:d915:b63a
602c19:dd:d9:dd:c25:c25:d915:b63b/1282c19:dd:d9:dd:c25:c25:d915:b63b
612c19:dd:d9:dd:c25:c25:d915:b63c/1282c19:dd:d9:dd:c25:c25:d915:b63c
622c19:dd:d9:dd:c25:c25:d915:b63d/1282c19:dd:d9:dd:c25:c25:d915:b63d
632c19:dd:d9:dd:c25:c25:d915:b63e/1282c19:dd:d9:dd:c25:c25:d915:b63e
642c19:dd:d9:dd:c25:c25:d915:b63f/1282c19:dd:d9:dd:c25:c25:d915:b63f
652c19:dd:d9:dd:c25:c25:d915:b640/1282c19:dd:d9:dd:c25:c25:d915:b640
662c19:dd:d9:dd:c25:c25:d915:b641/1282c19:dd:d9:dd:c25:c25:d915:b641
672c19:dd:d9:dd:c25:c25:d915:b642/1282c19:dd:d9:dd:c25:c25:d915:b642
682c19:dd:d9:dd:c25:c25:d915:b643/1282c19:dd:d9:dd:c25:c25:d915:b643
692c19:dd:d9:dd:c25:c25:d915:b644/1282c19:dd:d9:dd:c25:c25:d915:b644
702c19:dd:d9:dd:c25:c25:d915:b645/1282c19:dd:d9:dd:c25:c25:d915:b645
712c19:dd:d9:dd:c25:c25:d915:b646/1282c19:dd:d9:dd:c25:c25:d915:b646
722c19:dd:d9:dd:c25:c25:d915:b647/1282c19:dd:d9:dd:c25:c25:d915:b647
732c19:dd:d9:dd:c25:c25:d915:b648/1282c19:dd:d9:dd:c25:c25:d915:b648
742c19:dd:d9:dd:c25:c25:d915:b649/1282c19:dd:d9:dd:c25:c25:d915:b649
752c19:dd:d9:dd:c25:c25:d915:b64a/1282c19:dd:d9:dd:c25:c25:d915:b64a
762c19:dd:d9:dd:c25:c25:d915:b64b/1282c19:dd:d9:dd:c25:c25:d915:b64b
772c19:dd:d9:dd:c25:c25:d915:b64c/1282c19:dd:d9:dd:c25:c25:d915:b64c
782c19:dd:d9:dd:c25:c25:d915:b64d/1282c19:dd:d9:dd:c25:c25:d915:b64d
792c19:dd:d9:dd:c25:c25:d915:b64e/1282c19:dd:d9:dd:c25:c25:d915:b64e
802c19:dd:d9:dd:c25:c25:d915:b64f/1282c19:dd:d9:dd:c25:c25:d915:b64f
812c19:dd:d9:dd:c25:c25:d915:b650/1282c19:dd:d9:dd:c25:c25:d915:b650
822c19:dd:d9:dd:c25:c25:d915:b651/1282c19:dd:d9:dd:c25:c25:d915:b651
832c19:dd:d9:dd:c25:c25:d915:b652/1282c19:dd:d9:dd:c25:c25:d915:b652
842c19:dd:d9:dd:c25:c25:d915:b653/1282c19:dd:d9:dd:c25:c25:d915:b653
852c19:dd:d9:dd:c25:c25:d915:b654/1282c19:dd:d9:dd:c25:c25:d915:b654
862c19:dd:d9:dd:c25:c25:d915:b655/1282c19:dd:d9:dd:c25:c25:d915:b655
872c19:dd:d9:dd:c25:c25:d915:b656/1282c19:dd:d9:dd:c25:c25:d915:b656
882c19:dd:d9:dd:c25:c25:d915:b657/1282c19:dd:d9:dd:c25:c25:d915:b657
892c19:dd:d9:dd:c25:c25:d915:b658/1282c19:dd:d9:dd:c25:c25:d915:b658
902c19:dd:d9:dd:c25:c25:d915:b659/1282c19:dd:d9:dd:c25:c25:d915:b659
912c19:dd:d9:dd:c25:c25:d915:b65a/1282c19:dd:d9:dd:c25:c25:d915:b65a
922c19:dd:d9:dd:c25:c25:d915:b65b/1282c19:dd:d9:dd:c25:c25:d915:b65b
932c19:dd:d9:dd:c25:c25:d915:b65c/1282c19:dd:d9:dd:c25:c25:d915:b65c
942c19:dd:d9:dd:c25:c25:d915:b65d/1282c19:dd:d9:dd:c25:c25:d915:b65d
952c19:dd:d9:dd:c25:c25:d915:b65e/1282c19:dd:d9:dd:c25:c25:d915:b65e
962c19:dd:d9:dd:c25:c25:d915:b65f/1282c19:dd:d9:dd:c25:c25:d915:b65f
972c19:dd:d9:dd:c25:c25:d915:b660/1282c19:dd:d9:dd:c25:c25:d915:b660
982c19:dd:d9:dd:c25:c25:d915:b661/1282c19:dd:d9:dd:c25:c25:d915:b661
992c19:dd:d9:dd:c25:c25:d915:b662/1282c19:dd:d9:dd:c25:c25:d915:b662
1002c19:dd:d9:dd:c25:c25:d915:b663/1282c19:dd:d9:dd:c25:c25:d915:b663
1012c19:dd:d9:dd:c25:c25:d915:b664/1282c19:dd:d9:dd:c25:c25:d915:b664
1022c19:dd:d9:dd:c25:c25:d915:b665/1282c19:dd:d9:dd:c25:c25:d915:b665
1032c19:dd:d9:dd:c25:c25:d915:b666/1282c19:dd:d9:dd:c25:c25:d915:b666
1042c19:dd:d9:dd:c25:c25:d915:b667/1282c19:dd:d9:dd:c25:c25:d915:b667
1052c19:dd:d9:dd:c25:c25:d915:b668/1282c19:dd:d9:dd:c25:c25:d915:b668
1062c19:dd:d9:dd:c25:c25:d915:b669/1282c19:dd:d9:dd:c25:c25:d915:b669
1072c19:dd:d9:dd:c25:c25:d915:b66a/1282c19:dd:d9:dd:c25:c25:d915:b66a
1082c19:dd:d9:dd:c25:c25:d915:b66b/1282c19:dd:d9:dd:c25:c25:d915:b66b
1092c19:dd:d9:dd:c25:c25:d915:b66c/1282c19:dd:d9:dd:c25:c25:d915:b66c
1102c19:dd:d9:dd:c25:c25:d915:b66d/1282c19:dd:d9:dd:c25:c25:d915:b66d
1112c19:dd:d9:dd:c25:c25:d915:b66e/1282c19:dd:d9:dd:c25:c25:d915:b66e
1122c19:dd:d9:dd:c25:c25:d915:b66f/1282c19:dd:d9:dd:c25:c25:d915:b66f
1132c19:dd:d9:dd:c25:c25:d915:b670/1282c19:dd:d9:dd:c25:c25:d915:b670
1142c19:dd:d9:dd:c25:c25:d915:b671/1282c19:dd:d9:dd:c25:c25:d915:b671
1152c19:dd:d9:dd:c25:c25:d915:b672/1282c19:dd:d9:dd:c25:c25:d915:b672
1162c19:dd:d9:dd:c25:c25:d915:b673/1282c19:dd:d9:dd:c25:c25:d915:b673
1172c19:dd:d9:dd:c25:c25:d915:b674/1282c19:dd:d9:dd:c25:c25:d915:b674
1182c19:dd:d9:dd:c25:c25:d915:b675/1282c19:dd:d9:dd:c25:c25:d915:b675
1192c19:dd:d9:dd:c25:c25:d915:b676/1282c19:dd:d9:dd:c25:c25:d915:b676
1202c19:dd:d9:dd:c25:c25:d915:b677/1282c19:dd:d9:dd:c25:c25:d915:b677
1212c19:dd:d9:dd:c25:c25:d915:b678/1282c19:dd:d9:dd:c25:c25:d915:b678
1222c19:dd:d9:dd:c25:c25:d915:b679/1282c19:dd:d9:dd:c25:c25:d915:b679
1232c19:dd:d9:dd:c25:c25:d915:b67a/1282c19:dd:d9:dd:c25:c25:d915:b67a
1242c19:dd:d9:dd:c25:c25:d915:b67b/1282c19:dd:d9:dd:c25:c25:d915:b67b
1252c19:dd:d9:dd:c25:c25:d915:b67c/1282c19:dd:d9:dd:c25:c25:d915:b67c
1262c19:dd:d9:dd:c25:c25:d915:b67d/1282c19:dd:d9:dd:c25:c25:d915:b67d
1272c19:dd:d9:dd:c25:c25:d915:b67e/1282c19:dd:d9:dd:c25:c25:d915:b67e
1282c19:dd:d9:dd:c25:c25:d915:b67f/1282c19:dd:d9:dd:c25:c25:d915:b67f
1292c19:dd:d9:dd:c25:c25:d915:b680/1282c19:dd:d9:dd:c25:c25:d915:b680
1302c19:dd:d9:dd:c25:c25:d915:b681/1282c19:dd:d9:dd:c25:c25:d915:b681
1312c19:dd:d9:dd:c25:c25:d915:b682/1282c19:dd:d9:dd:c25:c25:d915:b682
1322c19:dd:d9:dd:c25:c25:d915:b683/1282c19:dd:d9:dd:c25:c25:d915:b683
1332c19:dd:d9:dd:c25:c25:d915:b684/1282c19:dd:d9:dd:c25:c25:d915:b684
1342c19:dd:d9:dd:c25:c25:d915:b685/1282c19:dd:d9:dd:c25:c25:d915:b685
1352c19:dd:d9:dd:c25:c25:d915:b686/1282c19:dd:d9:dd:c25:c25:d915:b686
1362c19:dd:d9:dd:c25:c25:d915:b687/1282c19:dd:d9:dd:c25:c25:d915:b687
1372c19:dd:d9:dd:c25:c25:d915:b688/1282c19:dd:d9:dd:c25:c25:d915:b688
1382c19:dd:d9:dd:c25:c25:d915:b689/1282c19:dd:d9:dd:c25:c25:d915:b689
1392c19:dd:d9:dd:c25:c25:d915:b68a/1282c19:dd:d9:dd:c25:c25:d915:b68a
1402c19:dd:d9:dd:c25:c25:d915:b68b/1282c19:dd:d9:dd:c25:c25:d915:b68b
1412c19:dd:d9:dd:c25:c25:d915:b68c/1282c19:dd:d9:dd:c25:c25:d915:b68c
1422c19:dd:d9:dd:c25:c25:d915:b68d/1282c19:dd:d9:dd:c25:c25:d915:b68d
1432c19:dd:d9:dd:c25:c25:d915:b68e/1282c19:dd:d9:dd:c25:c25:d915:b68e
1442c19:dd:d9:dd:c25:c25:d915:b68f/1282c19:dd:d9:dd:c25:c25:d915:b68f
1452c19:dd:d9:dd:c25:c25:d915:b690/1282c19:dd:d9:dd:c25:c25:d915:b690
1462c19:dd:d9:dd:c25:c25:d915:b691/1282c19:dd:d9:dd:c25:c25:d915:b691
1472c19:dd:d9:dd:c25:c25:d915:b692/1282c19:dd:d9:dd:c25:c25:d915:b692
1482c19:dd:d9:dd:c25:c25:d915:b693/1282c19:dd:d9:dd:c25:c25:d915:b693
1492c19:dd:d9:dd:c25:c25:d915:b694/1282c19:dd:d9:dd:c25:c25:d915:b694
1502c19:dd:d9:dd:c25:c25:d915:b695/1282c19:dd:d9:dd:c25:c25:d915:b695
1512c19:dd:d9:dd:c25:c25:d915:b696/1282c19:dd:d9:dd:c25:c25:d915:b696
1522c19:dd:d9:dd:c25:c25:d915:b697/1282c19:dd:d9:dd:c25:c25:d915:b697
1532c19:dd:d9:dd:c25:c25:d915:b698/1282c19:dd:d9:dd:c25:c25:d915:b698
1542c19:dd:d9:dd:c25:c25:d915:b699/1282c19:dd:d9:dd:c25:c25:d915:b699
1552c19:dd:d9:dd:c25:c25:d915:b69a/1282c19:dd:d9:dd:c25:c25:d915:b69a
1562c19:dd:d9:dd:c25:c25:d915:b69b/1282c19:dd:d9:dd:c25:c25:d915:b69b
1572c19:dd:d9:dd:c25:c25:d915:b69c/1282c19:dd:d9:dd:c25:c25:d915:b69c
1582c19:dd:d9:dd:c25:c25:d915:b69d/1282c19:dd:d9:dd:c25:c25:d915:b69d
1592c19:dd:d9:dd:c25:c25:d915:b69e/1282c19:dd:d9:dd:c25:c25:d915:b69e
1602c19:dd:d9:dd:c25:c25:d915:b69f/1282c19:dd:d9:dd:c25:c25:d915:b69f
1612c19:dd:d9:dd:c25:c25:d915:b6a0/1282c19:dd:d9:dd:c25:c25:d915:b6a0
1622c19:dd:d9:dd:c25:c25:d915:b6a1/1282c19:dd:d9:dd:c25:c25:d915:b6a1
1632c19:dd:d9:dd:c25:c25:d915:b6a2/1282c19:dd:d9:dd:c25:c25:d915:b6a2
1642c19:dd:d9:dd:c25:c25:d915:b6a3/1282c19:dd:d9:dd:c25:c25:d915:b6a3
1652c19:dd:d9:dd:c25:c25:d915:b6a4/1282c19:dd:d9:dd:c25:c25:d915:b6a4
1662c19:dd:d9:dd:c25:c25:d915:b6a5/1282c19:dd:d9:dd:c25:c25:d915:b6a5
1672c19:dd:d9:dd:c25:c25:d915:b6a6/1282c19:dd:d9:dd:c25:c25:d915:b6a6
1682c19:dd:d9:dd:c25:c25:d915:b6a7/1282c19:dd:d9:dd:c25:c25:d915:b6a7
1692c19:dd:d9:dd:c25:c25:d915:b6a8/1282c19:dd:d9:dd:c25:c25:d915:b6a8
1702c19:dd:d9:dd:c25:c25:d915:b6a9/1282c19:dd:d9:dd:c25:c25:d915:b6a9
1712c19:dd:d9:dd:c25:c25:d915:b6aa/1282c19:dd:d9:dd:c25:c25:d915:b6aa
1722c19:dd:d9:dd:c25:c25:d915:b6ab/1282c19:dd:d9:dd:c25:c25:d915:b6ab
1732c19:dd:d9:dd:c25:c25:d915:b6ac/1282c19:dd:d9:dd:c25:c25:d915:b6ac
1742c19:dd:d9:dd:c25:c25:d915:b6ad/1282c19:dd:d9:dd:c25:c25:d915:b6ad
1752c19:dd:d9:dd:c25:c25:d915:b6ae/1282c19:dd:d9:dd:c25:c25:d915:b6ae
1762c19:dd:d9:dd:c25:c25:d915:b6af/1282c19:dd:d9:dd:c25:c25:d915:b6af
1772c19:dd:d9:dd:c25:c25:d915:b6b0/1282c19:dd:d9:dd:c25:c25:d915:b6b0
1782c19:dd:d9:dd:c25:c25:d915:b6b1/1282c19:dd:d9:dd:c25:c25:d915:b6b1
1792c19:dd:d9:dd:c25:c25:d915:b6b2/1282c19:dd:d9:dd:c25:c25:d915:b6b2
1802c19:dd:d9:dd:c25:c25:d915:b6b3/1282c19:dd:d9:dd:c25:c25:d915:b6b3
1812c19:dd:d9:dd:c25:c25:d915:b6b4/1282c19:dd:d9:dd:c25:c25:d915:b6b4
1822c19:dd:d9:dd:c25:c25:d915:b6b5/1282c19:dd:d9:dd:c25:c25:d915:b6b5
1832c19:dd:d9:dd:c25:c25:d915:b6b6/1282c19:dd:d9:dd:c25:c25:d915:b6b6
1842c19:dd:d9:dd:c25:c25:d915:b6b7/1282c19:dd:d9:dd:c25:c25:d915:b6b7
1852c19:dd:d9:dd:c25:c25:d915:b6b8/1282c19:dd:d9:dd:c25:c25:d915:b6b8
1862c19:dd:d9:dd:c25:c25:d915:b6b9/1282c19:dd:d9:dd:c25:c25:d915:b6b9
1872c19:dd:d9:dd:c25:c25:d915:b6ba/1282c19:dd:d9:dd:c25:c25:d915:b6ba
1882c19:dd:d9:dd:c25:c25:d915:b6bb/1282c19:dd:d9:dd:c25:c25:d915:b6bb
1892c19:dd:d9:dd:c25:c25:d915:b6bc/1282c19:dd:d9:dd:c25:c25:d915:b6bc
1902c19:dd:d9:dd:c25:c25:d915:b6bd/1282c19:dd:d9:dd:c25:c25:d915:b6bd
1912c19:dd:d9:dd:c25:c25:d915:b6be/1282c19:dd:d9:dd:c25:c25:d915:b6be
1922c19:dd:d9:dd:c25:c25:d915:b6bf/1282c19:dd:d9:dd:c25:c25:d915:b6bf
1932c19:dd:d9:dd:c25:c25:d915:b6c0/1282c19:dd:d9:dd:c25:c25:d915:b6c0
1942c19:dd:d9:dd:c25:c25:d915:b6c1/1282c19:dd:d9:dd:c25:c25:d915:b6c1
1952c19:dd:d9:dd:c25:c25:d915:b6c2/1282c19:dd:d9:dd:c25:c25:d915:b6c2
1962c19:dd:d9:dd:c25:c25:d915:b6c3/1282c19:dd:d9:dd:c25:c25:d915:b6c3
1972c19:dd:d9:dd:c25:c25:d915:b6c4/1282c19:dd:d9:dd:c25:c25:d915:b6c4
1982c19:dd:d9:dd:c25:c25:d915:b6c5/1282c19:dd:d9:dd:c25:c25:d915:b6c5
1992c19:dd:d9:dd:c25:c25:d915:b6c6/1282c19:dd:d9:dd:c25:c25:d915:b6c6
2002c19:dd:d9:dd:c25:c25:d915:b6c7/1282c19:dd:d9:dd:c25:c25:d915:b6c7
2012c19:dd:d9:dd:c25:c25:d915:b6c8/1282c19:dd:d9:dd:c25:c25:d915:b6c8
2022c19:dd:d9:dd:c25:c25:d915:b6c9/1282c19:dd:d9:dd:c25:c25:d915:b6c9
2032c19:dd:d9:dd:c25:c25:d915:b6ca/1282c19:dd:d9:dd:c25:c25:d915:b6ca
2042c19:dd:d9:dd:c25:c25:d915:b6cb/1282c19:dd:d9:dd:c25:c25:d915:b6cb
2052c19:dd:d9:dd:c25:c25:d915:b6cc/1282c19:dd:d9:dd:c25:c25:d915:b6cc
2062c19:dd:d9:dd:c25:c25:d915:b6cd/1282c19:dd:d9:dd:c25:c25:d915:b6cd
2072c19:dd:d9:dd:c25:c25:d915:b6ce/1282c19:dd:d9:dd:c25:c25:d915:b6ce
2082c19:dd:d9:dd:c25:c25:d915:b6cf/1282c19:dd:d9:dd:c25:c25:d915:b6cf
2092c19:dd:d9:dd:c25:c25:d915:b6d0/1282c19:dd:d9:dd:c25:c25:d915:b6d0
2102c19:dd:d9:dd:c25:c25:d915:b6d1/1282c19:dd:d9:dd:c25:c25:d915:b6d1
2112c19:dd:d9:dd:c25:c25:d915:b6d2/1282c19:dd:d9:dd:c25:c25:d915:b6d2
2122c19:dd:d9:dd:c25:c25:d915:b6d3/1282c19:dd:d9:dd:c25:c25:d915:b6d3
2132c19:dd:d9:dd:c25:c25:d915:b6d4/1282c19:dd:d9:dd:c25:c25:d915:b6d4
2142c19:dd:d9:dd:c25:c25:d915:b6d5/1282c19:dd:d9:dd:c25:c25:d915:b6d5
2152c19:dd:d9:dd:c25:c25:d915:b6d6/1282c19:dd:d9:dd:c25:c25:d915:b6d6
2162c19:dd:d9:dd:c25:c25:d915:b6d7/1282c19:dd:d9:dd:c25:c25:d915:b6d7
2172c19:dd:d9:dd:c25:c25:d915:b6d8/1282c19:dd:d9:dd:c25:c25:d915:b6d8
2182c19:dd:d9:dd:c25:c25:d915:b6d9/1282c19:dd:d9:dd:c25:c25:d915:b6d9
2192c19:dd:d9:dd:c25:c25:d915:b6da/1282c19:dd:d9:dd:c25:c25:d915:b6da
2202c19:dd:d9:dd:c25:c25:d915:b6db/1282c19:dd:d9:dd:c25:c25:d915:b6db
2212c19:dd:d9:dd:c25:c25:d915:b6dc/1282c19:dd:d9:dd:c25:c25:d915:b6dc
2222c19:dd:d9:dd:c25:c25:d915:b6dd/1282c19:dd:d9:dd:c25:c25:d915:b6dd
2232c19:dd:d9:dd:c25:c25:d915:b6de/1282c19:dd:d9:dd:c25:c25:d915:b6de
2242c19:dd:d9:dd:c25:c25:d915:b6df/1282c19:dd:d9:dd:c25:c25:d915:b6df
2252c19:dd:d9:dd:c25:c25:d915:b6e0/1282c19:dd:d9:dd:c25:c25:d915:b6e0
2262c19:dd:d9:dd:c25:c25:d915:b6e1/1282c19:dd:d9:dd:c25:c25:d915:b6e1
2272c19:dd:d9:dd:c25:c25:d915:b6e2/1282c19:dd:d9:dd:c25:c25:d915:b6e2
2282c19:dd:d9:dd:c25:c25:d915:b6e3/1282c19:dd:d9:dd:c25:c25:d915:b6e3
2292c19:dd:d9:dd:c25:c25:d915:b6e4/1282c19:dd:d9:dd:c25:c25:d915:b6e4
2302c19:dd:d9:dd:c25:c25:d915:b6e5/1282c19:dd:d9:dd:c25:c25:d915:b6e5
2312c19:dd:d9:dd:c25:c25:d915:b6e6/1282c19:dd:d9:dd:c25:c25:d915:b6e6
2322c19:dd:d9:dd:c25:c25:d915:b6e7/1282c19:dd:d9:dd:c25:c25:d915:b6e7
2332c19:dd:d9:dd:c25:c25:d915:b6e8/1282c19:dd:d9:dd:c25:c25:d915:b6e8
2342c19:dd:d9:dd:c25:c25:d915:b6e9/1282c19:dd:d9:dd:c25:c25:d915:b6e9
2352c19:dd:d9:dd:c25:c25:d915:b6ea/1282c19:dd:d9:dd:c25:c25:d915:b6ea
2362c19:dd:d9:dd:c25:c25:d915:b6eb/1282c19:dd:d9:dd:c25:c25:d915:b6eb
2372c19:dd:d9:dd:c25:c25:d915:b6ec/1282c19:dd:d9:dd:c25:c25:d915:b6ec
2382c19:dd:d9:dd:c25:c25:d915:b6ed/1282c19:dd:d9:dd:c25:c25:d915:b6ed
2392c19:dd:d9:dd:c25:c25:d915:b6ee/1282c19:dd:d9:dd:c25:c25:d915:b6ee
2402c19:dd:d9:dd:c25:c25:d915:b6ef/1282c19:dd:d9:dd:c25:c25:d915:b6ef
2412c19:dd:d9:dd:c25:c25:d915:b6f0/1282c19:dd:d9:dd:c25:c25:d915:b6f0
2422c19:dd:d9:dd:c25:c25:d915:b6f1/1282c19:dd:d9:dd:c25:c25:d915:b6f1
2432c19:dd:d9:dd:c25:c25:d915:b6f2/1282c19:dd:d9:dd:c25:c25:d915:b6f2
2442c19:dd:d9:dd:c25:c25:d915:b6f3/1282c19:dd:d9:dd:c25:c25:d915:b6f3
2452c19:dd:d9:dd:c25:c25:d915:b6f4/1282c19:dd:d9:dd:c25:c25:d915:b6f4
2462c19:dd:d9:dd:c25:c25:d915:b6f5/1282c19:dd:d9:dd:c25:c25:d915:b6f5
2472c19:dd:d9:dd:c25:c25:d915:b6f6/1282c19:dd:d9:dd:c25:c25:d915:b6f6
2482c19:dd:d9:dd:c25:c25:d915:b6f7/1282c19:dd:d9:dd:c25:c25:d915:b6f7
2492c19:dd:d9:dd:c25:c25:d915:b6f8/1282c19:dd:d9:dd:c25:c25:d915:b6f8
2502c19:dd:d9:dd:c25:c25:d915:b6f9/1282c19:dd:d9:dd:c25:c25:d915:b6f9
2512c19:dd:d9:dd:c25:c25:d915:b6fa/1282c19:dd:d9:dd:c25:c25:d915:b6fa
2522c19:dd:d9:dd:c25:c25:d915:b6fb/1282c19:dd:d9:dd:c25:c25:d915:b6fb
2532c19:dd:d9:dd:c25:c25:d915:b6fc/1282c19:dd:d9:dd:c25:c25:d915:b6fc
2542c19:dd:d9:dd:c25:c25:d915:b6fd/1282c19:dd:d9:dd:c25:c25:d915:b6fd
2552c19:dd:d9:dd:c25:c25:d915:b6fe/1282c19:dd:d9:dd:c25:c25:d915:b6fe
2562c19:dd:d9:dd:c25:c25:d915:b6ff/1282c19:dd:d9:dd:c25:c25:d915:b6ff

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.