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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:c25:c25d:dd:dd:dd:f600/120
First address
2c19:dd:c25:c25d:dd:dd:dd:f600
Last address
2c19:dd:c25:c25d:dd:dd:dd:f6ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:f600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.f.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.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:c25:c25d:dd:dd:dd:f600/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:f600/1282c19:dd:c25:c25d:dd:dd:dd:f600
22c19:dd:c25:c25d:dd:dd:dd:f601/1282c19:dd:c25:c25d:dd:dd:dd:f601
32c19:dd:c25:c25d:dd:dd:dd:f602/1282c19:dd:c25:c25d:dd:dd:dd:f602
42c19:dd:c25:c25d:dd:dd:dd:f603/1282c19:dd:c25:c25d:dd:dd:dd:f603
52c19:dd:c25:c25d:dd:dd:dd:f604/1282c19:dd:c25:c25d:dd:dd:dd:f604
62c19:dd:c25:c25d:dd:dd:dd:f605/1282c19:dd:c25:c25d:dd:dd:dd:f605
72c19:dd:c25:c25d:dd:dd:dd:f606/1282c19:dd:c25:c25d:dd:dd:dd:f606
82c19:dd:c25:c25d:dd:dd:dd:f607/1282c19:dd:c25:c25d:dd:dd:dd:f607
92c19:dd:c25:c25d:dd:dd:dd:f608/1282c19:dd:c25:c25d:dd:dd:dd:f608
102c19:dd:c25:c25d:dd:dd:dd:f609/1282c19:dd:c25:c25d:dd:dd:dd:f609
112c19:dd:c25:c25d:dd:dd:dd:f60a/1282c19:dd:c25:c25d:dd:dd:dd:f60a
122c19:dd:c25:c25d:dd:dd:dd:f60b/1282c19:dd:c25:c25d:dd:dd:dd:f60b
132c19:dd:c25:c25d:dd:dd:dd:f60c/1282c19:dd:c25:c25d:dd:dd:dd:f60c
142c19:dd:c25:c25d:dd:dd:dd:f60d/1282c19:dd:c25:c25d:dd:dd:dd:f60d
152c19:dd:c25:c25d:dd:dd:dd:f60e/1282c19:dd:c25:c25d:dd:dd:dd:f60e
162c19:dd:c25:c25d:dd:dd:dd:f60f/1282c19:dd:c25:c25d:dd:dd:dd:f60f
172c19:dd:c25:c25d:dd:dd:dd:f610/1282c19:dd:c25:c25d:dd:dd:dd:f610
182c19:dd:c25:c25d:dd:dd:dd:f611/1282c19:dd:c25:c25d:dd:dd:dd:f611
192c19:dd:c25:c25d:dd:dd:dd:f612/1282c19:dd:c25:c25d:dd:dd:dd:f612
202c19:dd:c25:c25d:dd:dd:dd:f613/1282c19:dd:c25:c25d:dd:dd:dd:f613
212c19:dd:c25:c25d:dd:dd:dd:f614/1282c19:dd:c25:c25d:dd:dd:dd:f614
222c19:dd:c25:c25d:dd:dd:dd:f615/1282c19:dd:c25:c25d:dd:dd:dd:f615
232c19:dd:c25:c25d:dd:dd:dd:f616/1282c19:dd:c25:c25d:dd:dd:dd:f616
242c19:dd:c25:c25d:dd:dd:dd:f617/1282c19:dd:c25:c25d:dd:dd:dd:f617
252c19:dd:c25:c25d:dd:dd:dd:f618/1282c19:dd:c25:c25d:dd:dd:dd:f618
262c19:dd:c25:c25d:dd:dd:dd:f619/1282c19:dd:c25:c25d:dd:dd:dd:f619
272c19:dd:c25:c25d:dd:dd:dd:f61a/1282c19:dd:c25:c25d:dd:dd:dd:f61a
282c19:dd:c25:c25d:dd:dd:dd:f61b/1282c19:dd:c25:c25d:dd:dd:dd:f61b
292c19:dd:c25:c25d:dd:dd:dd:f61c/1282c19:dd:c25:c25d:dd:dd:dd:f61c
302c19:dd:c25:c25d:dd:dd:dd:f61d/1282c19:dd:c25:c25d:dd:dd:dd:f61d
312c19:dd:c25:c25d:dd:dd:dd:f61e/1282c19:dd:c25:c25d:dd:dd:dd:f61e
322c19:dd:c25:c25d:dd:dd:dd:f61f/1282c19:dd:c25:c25d:dd:dd:dd:f61f
332c19:dd:c25:c25d:dd:dd:dd:f620/1282c19:dd:c25:c25d:dd:dd:dd:f620
342c19:dd:c25:c25d:dd:dd:dd:f621/1282c19:dd:c25:c25d:dd:dd:dd:f621
352c19:dd:c25:c25d:dd:dd:dd:f622/1282c19:dd:c25:c25d:dd:dd:dd:f622
362c19:dd:c25:c25d:dd:dd:dd:f623/1282c19:dd:c25:c25d:dd:dd:dd:f623
372c19:dd:c25:c25d:dd:dd:dd:f624/1282c19:dd:c25:c25d:dd:dd:dd:f624
382c19:dd:c25:c25d:dd:dd:dd:f625/1282c19:dd:c25:c25d:dd:dd:dd:f625
392c19:dd:c25:c25d:dd:dd:dd:f626/1282c19:dd:c25:c25d:dd:dd:dd:f626
402c19:dd:c25:c25d:dd:dd:dd:f627/1282c19:dd:c25:c25d:dd:dd:dd:f627
412c19:dd:c25:c25d:dd:dd:dd:f628/1282c19:dd:c25:c25d:dd:dd:dd:f628
422c19:dd:c25:c25d:dd:dd:dd:f629/1282c19:dd:c25:c25d:dd:dd:dd:f629
432c19:dd:c25:c25d:dd:dd:dd:f62a/1282c19:dd:c25:c25d:dd:dd:dd:f62a
442c19:dd:c25:c25d:dd:dd:dd:f62b/1282c19:dd:c25:c25d:dd:dd:dd:f62b
452c19:dd:c25:c25d:dd:dd:dd:f62c/1282c19:dd:c25:c25d:dd:dd:dd:f62c
462c19:dd:c25:c25d:dd:dd:dd:f62d/1282c19:dd:c25:c25d:dd:dd:dd:f62d
472c19:dd:c25:c25d:dd:dd:dd:f62e/1282c19:dd:c25:c25d:dd:dd:dd:f62e
482c19:dd:c25:c25d:dd:dd:dd:f62f/1282c19:dd:c25:c25d:dd:dd:dd:f62f
492c19:dd:c25:c25d:dd:dd:dd:f630/1282c19:dd:c25:c25d:dd:dd:dd:f630
502c19:dd:c25:c25d:dd:dd:dd:f631/1282c19:dd:c25:c25d:dd:dd:dd:f631
512c19:dd:c25:c25d:dd:dd:dd:f632/1282c19:dd:c25:c25d:dd:dd:dd:f632
522c19:dd:c25:c25d:dd:dd:dd:f633/1282c19:dd:c25:c25d:dd:dd:dd:f633
532c19:dd:c25:c25d:dd:dd:dd:f634/1282c19:dd:c25:c25d:dd:dd:dd:f634
542c19:dd:c25:c25d:dd:dd:dd:f635/1282c19:dd:c25:c25d:dd:dd:dd:f635
552c19:dd:c25:c25d:dd:dd:dd:f636/1282c19:dd:c25:c25d:dd:dd:dd:f636
562c19:dd:c25:c25d:dd:dd:dd:f637/1282c19:dd:c25:c25d:dd:dd:dd:f637
572c19:dd:c25:c25d:dd:dd:dd:f638/1282c19:dd:c25:c25d:dd:dd:dd:f638
582c19:dd:c25:c25d:dd:dd:dd:f639/1282c19:dd:c25:c25d:dd:dd:dd:f639
592c19:dd:c25:c25d:dd:dd:dd:f63a/1282c19:dd:c25:c25d:dd:dd:dd:f63a
602c19:dd:c25:c25d:dd:dd:dd:f63b/1282c19:dd:c25:c25d:dd:dd:dd:f63b
612c19:dd:c25:c25d:dd:dd:dd:f63c/1282c19:dd:c25:c25d:dd:dd:dd:f63c
622c19:dd:c25:c25d:dd:dd:dd:f63d/1282c19:dd:c25:c25d:dd:dd:dd:f63d
632c19:dd:c25:c25d:dd:dd:dd:f63e/1282c19:dd:c25:c25d:dd:dd:dd:f63e
642c19:dd:c25:c25d:dd:dd:dd:f63f/1282c19:dd:c25:c25d:dd:dd:dd:f63f
652c19:dd:c25:c25d:dd:dd:dd:f640/1282c19:dd:c25:c25d:dd:dd:dd:f640
662c19:dd:c25:c25d:dd:dd:dd:f641/1282c19:dd:c25:c25d:dd:dd:dd:f641
672c19:dd:c25:c25d:dd:dd:dd:f642/1282c19:dd:c25:c25d:dd:dd:dd:f642
682c19:dd:c25:c25d:dd:dd:dd:f643/1282c19:dd:c25:c25d:dd:dd:dd:f643
692c19:dd:c25:c25d:dd:dd:dd:f644/1282c19:dd:c25:c25d:dd:dd:dd:f644
702c19:dd:c25:c25d:dd:dd:dd:f645/1282c19:dd:c25:c25d:dd:dd:dd:f645
712c19:dd:c25:c25d:dd:dd:dd:f646/1282c19:dd:c25:c25d:dd:dd:dd:f646
722c19:dd:c25:c25d:dd:dd:dd:f647/1282c19:dd:c25:c25d:dd:dd:dd:f647
732c19:dd:c25:c25d:dd:dd:dd:f648/1282c19:dd:c25:c25d:dd:dd:dd:f648
742c19:dd:c25:c25d:dd:dd:dd:f649/1282c19:dd:c25:c25d:dd:dd:dd:f649
752c19:dd:c25:c25d:dd:dd:dd:f64a/1282c19:dd:c25:c25d:dd:dd:dd:f64a
762c19:dd:c25:c25d:dd:dd:dd:f64b/1282c19:dd:c25:c25d:dd:dd:dd:f64b
772c19:dd:c25:c25d:dd:dd:dd:f64c/1282c19:dd:c25:c25d:dd:dd:dd:f64c
782c19:dd:c25:c25d:dd:dd:dd:f64d/1282c19:dd:c25:c25d:dd:dd:dd:f64d
792c19:dd:c25:c25d:dd:dd:dd:f64e/1282c19:dd:c25:c25d:dd:dd:dd:f64e
802c19:dd:c25:c25d:dd:dd:dd:f64f/1282c19:dd:c25:c25d:dd:dd:dd:f64f
812c19:dd:c25:c25d:dd:dd:dd:f650/1282c19:dd:c25:c25d:dd:dd:dd:f650
822c19:dd:c25:c25d:dd:dd:dd:f651/1282c19:dd:c25:c25d:dd:dd:dd:f651
832c19:dd:c25:c25d:dd:dd:dd:f652/1282c19:dd:c25:c25d:dd:dd:dd:f652
842c19:dd:c25:c25d:dd:dd:dd:f653/1282c19:dd:c25:c25d:dd:dd:dd:f653
852c19:dd:c25:c25d:dd:dd:dd:f654/1282c19:dd:c25:c25d:dd:dd:dd:f654
862c19:dd:c25:c25d:dd:dd:dd:f655/1282c19:dd:c25:c25d:dd:dd:dd:f655
872c19:dd:c25:c25d:dd:dd:dd:f656/1282c19:dd:c25:c25d:dd:dd:dd:f656
882c19:dd:c25:c25d:dd:dd:dd:f657/1282c19:dd:c25:c25d:dd:dd:dd:f657
892c19:dd:c25:c25d:dd:dd:dd:f658/1282c19:dd:c25:c25d:dd:dd:dd:f658
902c19:dd:c25:c25d:dd:dd:dd:f659/1282c19:dd:c25:c25d:dd:dd:dd:f659
912c19:dd:c25:c25d:dd:dd:dd:f65a/1282c19:dd:c25:c25d:dd:dd:dd:f65a
922c19:dd:c25:c25d:dd:dd:dd:f65b/1282c19:dd:c25:c25d:dd:dd:dd:f65b
932c19:dd:c25:c25d:dd:dd:dd:f65c/1282c19:dd:c25:c25d:dd:dd:dd:f65c
942c19:dd:c25:c25d:dd:dd:dd:f65d/1282c19:dd:c25:c25d:dd:dd:dd:f65d
952c19:dd:c25:c25d:dd:dd:dd:f65e/1282c19:dd:c25:c25d:dd:dd:dd:f65e
962c19:dd:c25:c25d:dd:dd:dd:f65f/1282c19:dd:c25:c25d:dd:dd:dd:f65f
972c19:dd:c25:c25d:dd:dd:dd:f660/1282c19:dd:c25:c25d:dd:dd:dd:f660
982c19:dd:c25:c25d:dd:dd:dd:f661/1282c19:dd:c25:c25d:dd:dd:dd:f661
992c19:dd:c25:c25d:dd:dd:dd:f662/1282c19:dd:c25:c25d:dd:dd:dd:f662
1002c19:dd:c25:c25d:dd:dd:dd:f663/1282c19:dd:c25:c25d:dd:dd:dd:f663
1012c19:dd:c25:c25d:dd:dd:dd:f664/1282c19:dd:c25:c25d:dd:dd:dd:f664
1022c19:dd:c25:c25d:dd:dd:dd:f665/1282c19:dd:c25:c25d:dd:dd:dd:f665
1032c19:dd:c25:c25d:dd:dd:dd:f666/1282c19:dd:c25:c25d:dd:dd:dd:f666
1042c19:dd:c25:c25d:dd:dd:dd:f667/1282c19:dd:c25:c25d:dd:dd:dd:f667
1052c19:dd:c25:c25d:dd:dd:dd:f668/1282c19:dd:c25:c25d:dd:dd:dd:f668
1062c19:dd:c25:c25d:dd:dd:dd:f669/1282c19:dd:c25:c25d:dd:dd:dd:f669
1072c19:dd:c25:c25d:dd:dd:dd:f66a/1282c19:dd:c25:c25d:dd:dd:dd:f66a
1082c19:dd:c25:c25d:dd:dd:dd:f66b/1282c19:dd:c25:c25d:dd:dd:dd:f66b
1092c19:dd:c25:c25d:dd:dd:dd:f66c/1282c19:dd:c25:c25d:dd:dd:dd:f66c
1102c19:dd:c25:c25d:dd:dd:dd:f66d/1282c19:dd:c25:c25d:dd:dd:dd:f66d
1112c19:dd:c25:c25d:dd:dd:dd:f66e/1282c19:dd:c25:c25d:dd:dd:dd:f66e
1122c19:dd:c25:c25d:dd:dd:dd:f66f/1282c19:dd:c25:c25d:dd:dd:dd:f66f
1132c19:dd:c25:c25d:dd:dd:dd:f670/1282c19:dd:c25:c25d:dd:dd:dd:f670
1142c19:dd:c25:c25d:dd:dd:dd:f671/1282c19:dd:c25:c25d:dd:dd:dd:f671
1152c19:dd:c25:c25d:dd:dd:dd:f672/1282c19:dd:c25:c25d:dd:dd:dd:f672
1162c19:dd:c25:c25d:dd:dd:dd:f673/1282c19:dd:c25:c25d:dd:dd:dd:f673
1172c19:dd:c25:c25d:dd:dd:dd:f674/1282c19:dd:c25:c25d:dd:dd:dd:f674
1182c19:dd:c25:c25d:dd:dd:dd:f675/1282c19:dd:c25:c25d:dd:dd:dd:f675
1192c19:dd:c25:c25d:dd:dd:dd:f676/1282c19:dd:c25:c25d:dd:dd:dd:f676
1202c19:dd:c25:c25d:dd:dd:dd:f677/1282c19:dd:c25:c25d:dd:dd:dd:f677
1212c19:dd:c25:c25d:dd:dd:dd:f678/1282c19:dd:c25:c25d:dd:dd:dd:f678
1222c19:dd:c25:c25d:dd:dd:dd:f679/1282c19:dd:c25:c25d:dd:dd:dd:f679
1232c19:dd:c25:c25d:dd:dd:dd:f67a/1282c19:dd:c25:c25d:dd:dd:dd:f67a
1242c19:dd:c25:c25d:dd:dd:dd:f67b/1282c19:dd:c25:c25d:dd:dd:dd:f67b
1252c19:dd:c25:c25d:dd:dd:dd:f67c/1282c19:dd:c25:c25d:dd:dd:dd:f67c
1262c19:dd:c25:c25d:dd:dd:dd:f67d/1282c19:dd:c25:c25d:dd:dd:dd:f67d
1272c19:dd:c25:c25d:dd:dd:dd:f67e/1282c19:dd:c25:c25d:dd:dd:dd:f67e
1282c19:dd:c25:c25d:dd:dd:dd:f67f/1282c19:dd:c25:c25d:dd:dd:dd:f67f
1292c19:dd:c25:c25d:dd:dd:dd:f680/1282c19:dd:c25:c25d:dd:dd:dd:f680
1302c19:dd:c25:c25d:dd:dd:dd:f681/1282c19:dd:c25:c25d:dd:dd:dd:f681
1312c19:dd:c25:c25d:dd:dd:dd:f682/1282c19:dd:c25:c25d:dd:dd:dd:f682
1322c19:dd:c25:c25d:dd:dd:dd:f683/1282c19:dd:c25:c25d:dd:dd:dd:f683
1332c19:dd:c25:c25d:dd:dd:dd:f684/1282c19:dd:c25:c25d:dd:dd:dd:f684
1342c19:dd:c25:c25d:dd:dd:dd:f685/1282c19:dd:c25:c25d:dd:dd:dd:f685
1352c19:dd:c25:c25d:dd:dd:dd:f686/1282c19:dd:c25:c25d:dd:dd:dd:f686
1362c19:dd:c25:c25d:dd:dd:dd:f687/1282c19:dd:c25:c25d:dd:dd:dd:f687
1372c19:dd:c25:c25d:dd:dd:dd:f688/1282c19:dd:c25:c25d:dd:dd:dd:f688
1382c19:dd:c25:c25d:dd:dd:dd:f689/1282c19:dd:c25:c25d:dd:dd:dd:f689
1392c19:dd:c25:c25d:dd:dd:dd:f68a/1282c19:dd:c25:c25d:dd:dd:dd:f68a
1402c19:dd:c25:c25d:dd:dd:dd:f68b/1282c19:dd:c25:c25d:dd:dd:dd:f68b
1412c19:dd:c25:c25d:dd:dd:dd:f68c/1282c19:dd:c25:c25d:dd:dd:dd:f68c
1422c19:dd:c25:c25d:dd:dd:dd:f68d/1282c19:dd:c25:c25d:dd:dd:dd:f68d
1432c19:dd:c25:c25d:dd:dd:dd:f68e/1282c19:dd:c25:c25d:dd:dd:dd:f68e
1442c19:dd:c25:c25d:dd:dd:dd:f68f/1282c19:dd:c25:c25d:dd:dd:dd:f68f
1452c19:dd:c25:c25d:dd:dd:dd:f690/1282c19:dd:c25:c25d:dd:dd:dd:f690
1462c19:dd:c25:c25d:dd:dd:dd:f691/1282c19:dd:c25:c25d:dd:dd:dd:f691
1472c19:dd:c25:c25d:dd:dd:dd:f692/1282c19:dd:c25:c25d:dd:dd:dd:f692
1482c19:dd:c25:c25d:dd:dd:dd:f693/1282c19:dd:c25:c25d:dd:dd:dd:f693
1492c19:dd:c25:c25d:dd:dd:dd:f694/1282c19:dd:c25:c25d:dd:dd:dd:f694
1502c19:dd:c25:c25d:dd:dd:dd:f695/1282c19:dd:c25:c25d:dd:dd:dd:f695
1512c19:dd:c25:c25d:dd:dd:dd:f696/1282c19:dd:c25:c25d:dd:dd:dd:f696
1522c19:dd:c25:c25d:dd:dd:dd:f697/1282c19:dd:c25:c25d:dd:dd:dd:f697
1532c19:dd:c25:c25d:dd:dd:dd:f698/1282c19:dd:c25:c25d:dd:dd:dd:f698
1542c19:dd:c25:c25d:dd:dd:dd:f699/1282c19:dd:c25:c25d:dd:dd:dd:f699
1552c19:dd:c25:c25d:dd:dd:dd:f69a/1282c19:dd:c25:c25d:dd:dd:dd:f69a
1562c19:dd:c25:c25d:dd:dd:dd:f69b/1282c19:dd:c25:c25d:dd:dd:dd:f69b
1572c19:dd:c25:c25d:dd:dd:dd:f69c/1282c19:dd:c25:c25d:dd:dd:dd:f69c
1582c19:dd:c25:c25d:dd:dd:dd:f69d/1282c19:dd:c25:c25d:dd:dd:dd:f69d
1592c19:dd:c25:c25d:dd:dd:dd:f69e/1282c19:dd:c25:c25d:dd:dd:dd:f69e
1602c19:dd:c25:c25d:dd:dd:dd:f69f/1282c19:dd:c25:c25d:dd:dd:dd:f69f
1612c19:dd:c25:c25d:dd:dd:dd:f6a0/1282c19:dd:c25:c25d:dd:dd:dd:f6a0
1622c19:dd:c25:c25d:dd:dd:dd:f6a1/1282c19:dd:c25:c25d:dd:dd:dd:f6a1
1632c19:dd:c25:c25d:dd:dd:dd:f6a2/1282c19:dd:c25:c25d:dd:dd:dd:f6a2
1642c19:dd:c25:c25d:dd:dd:dd:f6a3/1282c19:dd:c25:c25d:dd:dd:dd:f6a3
1652c19:dd:c25:c25d:dd:dd:dd:f6a4/1282c19:dd:c25:c25d:dd:dd:dd:f6a4
1662c19:dd:c25:c25d:dd:dd:dd:f6a5/1282c19:dd:c25:c25d:dd:dd:dd:f6a5
1672c19:dd:c25:c25d:dd:dd:dd:f6a6/1282c19:dd:c25:c25d:dd:dd:dd:f6a6
1682c19:dd:c25:c25d:dd:dd:dd:f6a7/1282c19:dd:c25:c25d:dd:dd:dd:f6a7
1692c19:dd:c25:c25d:dd:dd:dd:f6a8/1282c19:dd:c25:c25d:dd:dd:dd:f6a8
1702c19:dd:c25:c25d:dd:dd:dd:f6a9/1282c19:dd:c25:c25d:dd:dd:dd:f6a9
1712c19:dd:c25:c25d:dd:dd:dd:f6aa/1282c19:dd:c25:c25d:dd:dd:dd:f6aa
1722c19:dd:c25:c25d:dd:dd:dd:f6ab/1282c19:dd:c25:c25d:dd:dd:dd:f6ab
1732c19:dd:c25:c25d:dd:dd:dd:f6ac/1282c19:dd:c25:c25d:dd:dd:dd:f6ac
1742c19:dd:c25:c25d:dd:dd:dd:f6ad/1282c19:dd:c25:c25d:dd:dd:dd:f6ad
1752c19:dd:c25:c25d:dd:dd:dd:f6ae/1282c19:dd:c25:c25d:dd:dd:dd:f6ae
1762c19:dd:c25:c25d:dd:dd:dd:f6af/1282c19:dd:c25:c25d:dd:dd:dd:f6af
1772c19:dd:c25:c25d:dd:dd:dd:f6b0/1282c19:dd:c25:c25d:dd:dd:dd:f6b0
1782c19:dd:c25:c25d:dd:dd:dd:f6b1/1282c19:dd:c25:c25d:dd:dd:dd:f6b1
1792c19:dd:c25:c25d:dd:dd:dd:f6b2/1282c19:dd:c25:c25d:dd:dd:dd:f6b2
1802c19:dd:c25:c25d:dd:dd:dd:f6b3/1282c19:dd:c25:c25d:dd:dd:dd:f6b3
1812c19:dd:c25:c25d:dd:dd:dd:f6b4/1282c19:dd:c25:c25d:dd:dd:dd:f6b4
1822c19:dd:c25:c25d:dd:dd:dd:f6b5/1282c19:dd:c25:c25d:dd:dd:dd:f6b5
1832c19:dd:c25:c25d:dd:dd:dd:f6b6/1282c19:dd:c25:c25d:dd:dd:dd:f6b6
1842c19:dd:c25:c25d:dd:dd:dd:f6b7/1282c19:dd:c25:c25d:dd:dd:dd:f6b7
1852c19:dd:c25:c25d:dd:dd:dd:f6b8/1282c19:dd:c25:c25d:dd:dd:dd:f6b8
1862c19:dd:c25:c25d:dd:dd:dd:f6b9/1282c19:dd:c25:c25d:dd:dd:dd:f6b9
1872c19:dd:c25:c25d:dd:dd:dd:f6ba/1282c19:dd:c25:c25d:dd:dd:dd:f6ba
1882c19:dd:c25:c25d:dd:dd:dd:f6bb/1282c19:dd:c25:c25d:dd:dd:dd:f6bb
1892c19:dd:c25:c25d:dd:dd:dd:f6bc/1282c19:dd:c25:c25d:dd:dd:dd:f6bc
1902c19:dd:c25:c25d:dd:dd:dd:f6bd/1282c19:dd:c25:c25d:dd:dd:dd:f6bd
1912c19:dd:c25:c25d:dd:dd:dd:f6be/1282c19:dd:c25:c25d:dd:dd:dd:f6be
1922c19:dd:c25:c25d:dd:dd:dd:f6bf/1282c19:dd:c25:c25d:dd:dd:dd:f6bf
1932c19:dd:c25:c25d:dd:dd:dd:f6c0/1282c19:dd:c25:c25d:dd:dd:dd:f6c0
1942c19:dd:c25:c25d:dd:dd:dd:f6c1/1282c19:dd:c25:c25d:dd:dd:dd:f6c1
1952c19:dd:c25:c25d:dd:dd:dd:f6c2/1282c19:dd:c25:c25d:dd:dd:dd:f6c2
1962c19:dd:c25:c25d:dd:dd:dd:f6c3/1282c19:dd:c25:c25d:dd:dd:dd:f6c3
1972c19:dd:c25:c25d:dd:dd:dd:f6c4/1282c19:dd:c25:c25d:dd:dd:dd:f6c4
1982c19:dd:c25:c25d:dd:dd:dd:f6c5/1282c19:dd:c25:c25d:dd:dd:dd:f6c5
1992c19:dd:c25:c25d:dd:dd:dd:f6c6/1282c19:dd:c25:c25d:dd:dd:dd:f6c6
2002c19:dd:c25:c25d:dd:dd:dd:f6c7/1282c19:dd:c25:c25d:dd:dd:dd:f6c7
2012c19:dd:c25:c25d:dd:dd:dd:f6c8/1282c19:dd:c25:c25d:dd:dd:dd:f6c8
2022c19:dd:c25:c25d:dd:dd:dd:f6c9/1282c19:dd:c25:c25d:dd:dd:dd:f6c9
2032c19:dd:c25:c25d:dd:dd:dd:f6ca/1282c19:dd:c25:c25d:dd:dd:dd:f6ca
2042c19:dd:c25:c25d:dd:dd:dd:f6cb/1282c19:dd:c25:c25d:dd:dd:dd:f6cb
2052c19:dd:c25:c25d:dd:dd:dd:f6cc/1282c19:dd:c25:c25d:dd:dd:dd:f6cc
2062c19:dd:c25:c25d:dd:dd:dd:f6cd/1282c19:dd:c25:c25d:dd:dd:dd:f6cd
2072c19:dd:c25:c25d:dd:dd:dd:f6ce/1282c19:dd:c25:c25d:dd:dd:dd:f6ce
2082c19:dd:c25:c25d:dd:dd:dd:f6cf/1282c19:dd:c25:c25d:dd:dd:dd:f6cf
2092c19:dd:c25:c25d:dd:dd:dd:f6d0/1282c19:dd:c25:c25d:dd:dd:dd:f6d0
2102c19:dd:c25:c25d:dd:dd:dd:f6d1/1282c19:dd:c25:c25d:dd:dd:dd:f6d1
2112c19:dd:c25:c25d:dd:dd:dd:f6d2/1282c19:dd:c25:c25d:dd:dd:dd:f6d2
2122c19:dd:c25:c25d:dd:dd:dd:f6d3/1282c19:dd:c25:c25d:dd:dd:dd:f6d3
2132c19:dd:c25:c25d:dd:dd:dd:f6d4/1282c19:dd:c25:c25d:dd:dd:dd:f6d4
2142c19:dd:c25:c25d:dd:dd:dd:f6d5/1282c19:dd:c25:c25d:dd:dd:dd:f6d5
2152c19:dd:c25:c25d:dd:dd:dd:f6d6/1282c19:dd:c25:c25d:dd:dd:dd:f6d6
2162c19:dd:c25:c25d:dd:dd:dd:f6d7/1282c19:dd:c25:c25d:dd:dd:dd:f6d7
2172c19:dd:c25:c25d:dd:dd:dd:f6d8/1282c19:dd:c25:c25d:dd:dd:dd:f6d8
2182c19:dd:c25:c25d:dd:dd:dd:f6d9/1282c19:dd:c25:c25d:dd:dd:dd:f6d9
2192c19:dd:c25:c25d:dd:dd:dd:f6da/1282c19:dd:c25:c25d:dd:dd:dd:f6da
2202c19:dd:c25:c25d:dd:dd:dd:f6db/1282c19:dd:c25:c25d:dd:dd:dd:f6db
2212c19:dd:c25:c25d:dd:dd:dd:f6dc/1282c19:dd:c25:c25d:dd:dd:dd:f6dc
2222c19:dd:c25:c25d:dd:dd:dd:f6dd/1282c19:dd:c25:c25d:dd:dd:dd:f6dd
2232c19:dd:c25:c25d:dd:dd:dd:f6de/1282c19:dd:c25:c25d:dd:dd:dd:f6de
2242c19:dd:c25:c25d:dd:dd:dd:f6df/1282c19:dd:c25:c25d:dd:dd:dd:f6df
2252c19:dd:c25:c25d:dd:dd:dd:f6e0/1282c19:dd:c25:c25d:dd:dd:dd:f6e0
2262c19:dd:c25:c25d:dd:dd:dd:f6e1/1282c19:dd:c25:c25d:dd:dd:dd:f6e1
2272c19:dd:c25:c25d:dd:dd:dd:f6e2/1282c19:dd:c25:c25d:dd:dd:dd:f6e2
2282c19:dd:c25:c25d:dd:dd:dd:f6e3/1282c19:dd:c25:c25d:dd:dd:dd:f6e3
2292c19:dd:c25:c25d:dd:dd:dd:f6e4/1282c19:dd:c25:c25d:dd:dd:dd:f6e4
2302c19:dd:c25:c25d:dd:dd:dd:f6e5/1282c19:dd:c25:c25d:dd:dd:dd:f6e5
2312c19:dd:c25:c25d:dd:dd:dd:f6e6/1282c19:dd:c25:c25d:dd:dd:dd:f6e6
2322c19:dd:c25:c25d:dd:dd:dd:f6e7/1282c19:dd:c25:c25d:dd:dd:dd:f6e7
2332c19:dd:c25:c25d:dd:dd:dd:f6e8/1282c19:dd:c25:c25d:dd:dd:dd:f6e8
2342c19:dd:c25:c25d:dd:dd:dd:f6e9/1282c19:dd:c25:c25d:dd:dd:dd:f6e9
2352c19:dd:c25:c25d:dd:dd:dd:f6ea/1282c19:dd:c25:c25d:dd:dd:dd:f6ea
2362c19:dd:c25:c25d:dd:dd:dd:f6eb/1282c19:dd:c25:c25d:dd:dd:dd:f6eb
2372c19:dd:c25:c25d:dd:dd:dd:f6ec/1282c19:dd:c25:c25d:dd:dd:dd:f6ec
2382c19:dd:c25:c25d:dd:dd:dd:f6ed/1282c19:dd:c25:c25d:dd:dd:dd:f6ed
2392c19:dd:c25:c25d:dd:dd:dd:f6ee/1282c19:dd:c25:c25d:dd:dd:dd:f6ee
2402c19:dd:c25:c25d:dd:dd:dd:f6ef/1282c19:dd:c25:c25d:dd:dd:dd:f6ef
2412c19:dd:c25:c25d:dd:dd:dd:f6f0/1282c19:dd:c25:c25d:dd:dd:dd:f6f0
2422c19:dd:c25:c25d:dd:dd:dd:f6f1/1282c19:dd:c25:c25d:dd:dd:dd:f6f1
2432c19:dd:c25:c25d:dd:dd:dd:f6f2/1282c19:dd:c25:c25d:dd:dd:dd:f6f2
2442c19:dd:c25:c25d:dd:dd:dd:f6f3/1282c19:dd:c25:c25d:dd:dd:dd:f6f3
2452c19:dd:c25:c25d:dd:dd:dd:f6f4/1282c19:dd:c25:c25d:dd:dd:dd:f6f4
2462c19:dd:c25:c25d:dd:dd:dd:f6f5/1282c19:dd:c25:c25d:dd:dd:dd:f6f5
2472c19:dd:c25:c25d:dd:dd:dd:f6f6/1282c19:dd:c25:c25d:dd:dd:dd:f6f6
2482c19:dd:c25:c25d:dd:dd:dd:f6f7/1282c19:dd:c25:c25d:dd:dd:dd:f6f7
2492c19:dd:c25:c25d:dd:dd:dd:f6f8/1282c19:dd:c25:c25d:dd:dd:dd:f6f8
2502c19:dd:c25:c25d:dd:dd:dd:f6f9/1282c19:dd:c25:c25d:dd:dd:dd:f6f9
2512c19:dd:c25:c25d:dd:dd:dd:f6fa/1282c19:dd:c25:c25d:dd:dd:dd:f6fa
2522c19:dd:c25:c25d:dd:dd:dd:f6fb/1282c19:dd:c25:c25d:dd:dd:dd:f6fb
2532c19:dd:c25:c25d:dd:dd:dd:f6fc/1282c19:dd:c25:c25d:dd:dd:dd:f6fc
2542c19:dd:c25:c25d:dd:dd:dd:f6fd/1282c19:dd:c25:c25d:dd:dd:dd:f6fd
2552c19:dd:c25:c25d:dd:dd:dd:f6fe/1282c19:dd:c25:c25d:dd:dd:dd:f6fe
2562c19:dd:c25:c25d:dd:dd:dd:f6ff/1282c19:dd:c25:c25d:dd:dd:dd:f6ff

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.