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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:f600/119
First address
2c19:dd:d9:dd:c25:c25:94de:f600
Last address
2c19:dd:d9:dd:c25:c25:94de:f7ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:f600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
6.f.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.f.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/127
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:94de:f600/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:f600/1272c19:dd:d9:dd:c25:c25:94de:f601
22c19:dd:d9:dd:c25:c25:94de:f602/1272c19:dd:d9:dd:c25:c25:94de:f603
32c19:dd:d9:dd:c25:c25:94de:f604/1272c19:dd:d9:dd:c25:c25:94de:f605
42c19:dd:d9:dd:c25:c25:94de:f606/1272c19:dd:d9:dd:c25:c25:94de:f607
52c19:dd:d9:dd:c25:c25:94de:f608/1272c19:dd:d9:dd:c25:c25:94de:f609
62c19:dd:d9:dd:c25:c25:94de:f60a/1272c19:dd:d9:dd:c25:c25:94de:f60b
72c19:dd:d9:dd:c25:c25:94de:f60c/1272c19:dd:d9:dd:c25:c25:94de:f60d
82c19:dd:d9:dd:c25:c25:94de:f60e/1272c19:dd:d9:dd:c25:c25:94de:f60f
92c19:dd:d9:dd:c25:c25:94de:f610/1272c19:dd:d9:dd:c25:c25:94de:f611
102c19:dd:d9:dd:c25:c25:94de:f612/1272c19:dd:d9:dd:c25:c25:94de:f613
112c19:dd:d9:dd:c25:c25:94de:f614/1272c19:dd:d9:dd:c25:c25:94de:f615
122c19:dd:d9:dd:c25:c25:94de:f616/1272c19:dd:d9:dd:c25:c25:94de:f617
132c19:dd:d9:dd:c25:c25:94de:f618/1272c19:dd:d9:dd:c25:c25:94de:f619
142c19:dd:d9:dd:c25:c25:94de:f61a/1272c19:dd:d9:dd:c25:c25:94de:f61b
152c19:dd:d9:dd:c25:c25:94de:f61c/1272c19:dd:d9:dd:c25:c25:94de:f61d
162c19:dd:d9:dd:c25:c25:94de:f61e/1272c19:dd:d9:dd:c25:c25:94de:f61f
172c19:dd:d9:dd:c25:c25:94de:f620/1272c19:dd:d9:dd:c25:c25:94de:f621
182c19:dd:d9:dd:c25:c25:94de:f622/1272c19:dd:d9:dd:c25:c25:94de:f623
192c19:dd:d9:dd:c25:c25:94de:f624/1272c19:dd:d9:dd:c25:c25:94de:f625
202c19:dd:d9:dd:c25:c25:94de:f626/1272c19:dd:d9:dd:c25:c25:94de:f627
212c19:dd:d9:dd:c25:c25:94de:f628/1272c19:dd:d9:dd:c25:c25:94de:f629
222c19:dd:d9:dd:c25:c25:94de:f62a/1272c19:dd:d9:dd:c25:c25:94de:f62b
232c19:dd:d9:dd:c25:c25:94de:f62c/1272c19:dd:d9:dd:c25:c25:94de:f62d
242c19:dd:d9:dd:c25:c25:94de:f62e/1272c19:dd:d9:dd:c25:c25:94de:f62f
252c19:dd:d9:dd:c25:c25:94de:f630/1272c19:dd:d9:dd:c25:c25:94de:f631
262c19:dd:d9:dd:c25:c25:94de:f632/1272c19:dd:d9:dd:c25:c25:94de:f633
272c19:dd:d9:dd:c25:c25:94de:f634/1272c19:dd:d9:dd:c25:c25:94de:f635
282c19:dd:d9:dd:c25:c25:94de:f636/1272c19:dd:d9:dd:c25:c25:94de:f637
292c19:dd:d9:dd:c25:c25:94de:f638/1272c19:dd:d9:dd:c25:c25:94de:f639
302c19:dd:d9:dd:c25:c25:94de:f63a/1272c19:dd:d9:dd:c25:c25:94de:f63b
312c19:dd:d9:dd:c25:c25:94de:f63c/1272c19:dd:d9:dd:c25:c25:94de:f63d
322c19:dd:d9:dd:c25:c25:94de:f63e/1272c19:dd:d9:dd:c25:c25:94de:f63f
332c19:dd:d9:dd:c25:c25:94de:f640/1272c19:dd:d9:dd:c25:c25:94de:f641
342c19:dd:d9:dd:c25:c25:94de:f642/1272c19:dd:d9:dd:c25:c25:94de:f643
352c19:dd:d9:dd:c25:c25:94de:f644/1272c19:dd:d9:dd:c25:c25:94de:f645
362c19:dd:d9:dd:c25:c25:94de:f646/1272c19:dd:d9:dd:c25:c25:94de:f647
372c19:dd:d9:dd:c25:c25:94de:f648/1272c19:dd:d9:dd:c25:c25:94de:f649
382c19:dd:d9:dd:c25:c25:94de:f64a/1272c19:dd:d9:dd:c25:c25:94de:f64b
392c19:dd:d9:dd:c25:c25:94de:f64c/1272c19:dd:d9:dd:c25:c25:94de:f64d
402c19:dd:d9:dd:c25:c25:94de:f64e/1272c19:dd:d9:dd:c25:c25:94de:f64f
412c19:dd:d9:dd:c25:c25:94de:f650/1272c19:dd:d9:dd:c25:c25:94de:f651
422c19:dd:d9:dd:c25:c25:94de:f652/1272c19:dd:d9:dd:c25:c25:94de:f653
432c19:dd:d9:dd:c25:c25:94de:f654/1272c19:dd:d9:dd:c25:c25:94de:f655
442c19:dd:d9:dd:c25:c25:94de:f656/1272c19:dd:d9:dd:c25:c25:94de:f657
452c19:dd:d9:dd:c25:c25:94de:f658/1272c19:dd:d9:dd:c25:c25:94de:f659
462c19:dd:d9:dd:c25:c25:94de:f65a/1272c19:dd:d9:dd:c25:c25:94de:f65b
472c19:dd:d9:dd:c25:c25:94de:f65c/1272c19:dd:d9:dd:c25:c25:94de:f65d
482c19:dd:d9:dd:c25:c25:94de:f65e/1272c19:dd:d9:dd:c25:c25:94de:f65f
492c19:dd:d9:dd:c25:c25:94de:f660/1272c19:dd:d9:dd:c25:c25:94de:f661
502c19:dd:d9:dd:c25:c25:94de:f662/1272c19:dd:d9:dd:c25:c25:94de:f663
512c19:dd:d9:dd:c25:c25:94de:f664/1272c19:dd:d9:dd:c25:c25:94de:f665
522c19:dd:d9:dd:c25:c25:94de:f666/1272c19:dd:d9:dd:c25:c25:94de:f667
532c19:dd:d9:dd:c25:c25:94de:f668/1272c19:dd:d9:dd:c25:c25:94de:f669
542c19:dd:d9:dd:c25:c25:94de:f66a/1272c19:dd:d9:dd:c25:c25:94de:f66b
552c19:dd:d9:dd:c25:c25:94de:f66c/1272c19:dd:d9:dd:c25:c25:94de:f66d
562c19:dd:d9:dd:c25:c25:94de:f66e/1272c19:dd:d9:dd:c25:c25:94de:f66f
572c19:dd:d9:dd:c25:c25:94de:f670/1272c19:dd:d9:dd:c25:c25:94de:f671
582c19:dd:d9:dd:c25:c25:94de:f672/1272c19:dd:d9:dd:c25:c25:94de:f673
592c19:dd:d9:dd:c25:c25:94de:f674/1272c19:dd:d9:dd:c25:c25:94de:f675
602c19:dd:d9:dd:c25:c25:94de:f676/1272c19:dd:d9:dd:c25:c25:94de:f677
612c19:dd:d9:dd:c25:c25:94de:f678/1272c19:dd:d9:dd:c25:c25:94de:f679
622c19:dd:d9:dd:c25:c25:94de:f67a/1272c19:dd:d9:dd:c25:c25:94de:f67b
632c19:dd:d9:dd:c25:c25:94de:f67c/1272c19:dd:d9:dd:c25:c25:94de:f67d
642c19:dd:d9:dd:c25:c25:94de:f67e/1272c19:dd:d9:dd:c25:c25:94de:f67f
652c19:dd:d9:dd:c25:c25:94de:f680/1272c19:dd:d9:dd:c25:c25:94de:f681
662c19:dd:d9:dd:c25:c25:94de:f682/1272c19:dd:d9:dd:c25:c25:94de:f683
672c19:dd:d9:dd:c25:c25:94de:f684/1272c19:dd:d9:dd:c25:c25:94de:f685
682c19:dd:d9:dd:c25:c25:94de:f686/1272c19:dd:d9:dd:c25:c25:94de:f687
692c19:dd:d9:dd:c25:c25:94de:f688/1272c19:dd:d9:dd:c25:c25:94de:f689
702c19:dd:d9:dd:c25:c25:94de:f68a/1272c19:dd:d9:dd:c25:c25:94de:f68b
712c19:dd:d9:dd:c25:c25:94de:f68c/1272c19:dd:d9:dd:c25:c25:94de:f68d
722c19:dd:d9:dd:c25:c25:94de:f68e/1272c19:dd:d9:dd:c25:c25:94de:f68f
732c19:dd:d9:dd:c25:c25:94de:f690/1272c19:dd:d9:dd:c25:c25:94de:f691
742c19:dd:d9:dd:c25:c25:94de:f692/1272c19:dd:d9:dd:c25:c25:94de:f693
752c19:dd:d9:dd:c25:c25:94de:f694/1272c19:dd:d9:dd:c25:c25:94de:f695
762c19:dd:d9:dd:c25:c25:94de:f696/1272c19:dd:d9:dd:c25:c25:94de:f697
772c19:dd:d9:dd:c25:c25:94de:f698/1272c19:dd:d9:dd:c25:c25:94de:f699
782c19:dd:d9:dd:c25:c25:94de:f69a/1272c19:dd:d9:dd:c25:c25:94de:f69b
792c19:dd:d9:dd:c25:c25:94de:f69c/1272c19:dd:d9:dd:c25:c25:94de:f69d
802c19:dd:d9:dd:c25:c25:94de:f69e/1272c19:dd:d9:dd:c25:c25:94de:f69f
812c19:dd:d9:dd:c25:c25:94de:f6a0/1272c19:dd:d9:dd:c25:c25:94de:f6a1
822c19:dd:d9:dd:c25:c25:94de:f6a2/1272c19:dd:d9:dd:c25:c25:94de:f6a3
832c19:dd:d9:dd:c25:c25:94de:f6a4/1272c19:dd:d9:dd:c25:c25:94de:f6a5
842c19:dd:d9:dd:c25:c25:94de:f6a6/1272c19:dd:d9:dd:c25:c25:94de:f6a7
852c19:dd:d9:dd:c25:c25:94de:f6a8/1272c19:dd:d9:dd:c25:c25:94de:f6a9
862c19:dd:d9:dd:c25:c25:94de:f6aa/1272c19:dd:d9:dd:c25:c25:94de:f6ab
872c19:dd:d9:dd:c25:c25:94de:f6ac/1272c19:dd:d9:dd:c25:c25:94de:f6ad
882c19:dd:d9:dd:c25:c25:94de:f6ae/1272c19:dd:d9:dd:c25:c25:94de:f6af
892c19:dd:d9:dd:c25:c25:94de:f6b0/1272c19:dd:d9:dd:c25:c25:94de:f6b1
902c19:dd:d9:dd:c25:c25:94de:f6b2/1272c19:dd:d9:dd:c25:c25:94de:f6b3
912c19:dd:d9:dd:c25:c25:94de:f6b4/1272c19:dd:d9:dd:c25:c25:94de:f6b5
922c19:dd:d9:dd:c25:c25:94de:f6b6/1272c19:dd:d9:dd:c25:c25:94de:f6b7
932c19:dd:d9:dd:c25:c25:94de:f6b8/1272c19:dd:d9:dd:c25:c25:94de:f6b9
942c19:dd:d9:dd:c25:c25:94de:f6ba/1272c19:dd:d9:dd:c25:c25:94de:f6bb
952c19:dd:d9:dd:c25:c25:94de:f6bc/1272c19:dd:d9:dd:c25:c25:94de:f6bd
962c19:dd:d9:dd:c25:c25:94de:f6be/1272c19:dd:d9:dd:c25:c25:94de:f6bf
972c19:dd:d9:dd:c25:c25:94de:f6c0/1272c19:dd:d9:dd:c25:c25:94de:f6c1
982c19:dd:d9:dd:c25:c25:94de:f6c2/1272c19:dd:d9:dd:c25:c25:94de:f6c3
992c19:dd:d9:dd:c25:c25:94de:f6c4/1272c19:dd:d9:dd:c25:c25:94de:f6c5
1002c19:dd:d9:dd:c25:c25:94de:f6c6/1272c19:dd:d9:dd:c25:c25:94de:f6c7
1012c19:dd:d9:dd:c25:c25:94de:f6c8/1272c19:dd:d9:dd:c25:c25:94de:f6c9
1022c19:dd:d9:dd:c25:c25:94de:f6ca/1272c19:dd:d9:dd:c25:c25:94de:f6cb
1032c19:dd:d9:dd:c25:c25:94de:f6cc/1272c19:dd:d9:dd:c25:c25:94de:f6cd
1042c19:dd:d9:dd:c25:c25:94de:f6ce/1272c19:dd:d9:dd:c25:c25:94de:f6cf
1052c19:dd:d9:dd:c25:c25:94de:f6d0/1272c19:dd:d9:dd:c25:c25:94de:f6d1
1062c19:dd:d9:dd:c25:c25:94de:f6d2/1272c19:dd:d9:dd:c25:c25:94de:f6d3
1072c19:dd:d9:dd:c25:c25:94de:f6d4/1272c19:dd:d9:dd:c25:c25:94de:f6d5
1082c19:dd:d9:dd:c25:c25:94de:f6d6/1272c19:dd:d9:dd:c25:c25:94de:f6d7
1092c19:dd:d9:dd:c25:c25:94de:f6d8/1272c19:dd:d9:dd:c25:c25:94de:f6d9
1102c19:dd:d9:dd:c25:c25:94de:f6da/1272c19:dd:d9:dd:c25:c25:94de:f6db
1112c19:dd:d9:dd:c25:c25:94de:f6dc/1272c19:dd:d9:dd:c25:c25:94de:f6dd
1122c19:dd:d9:dd:c25:c25:94de:f6de/1272c19:dd:d9:dd:c25:c25:94de:f6df
1132c19:dd:d9:dd:c25:c25:94de:f6e0/1272c19:dd:d9:dd:c25:c25:94de:f6e1
1142c19:dd:d9:dd:c25:c25:94de:f6e2/1272c19:dd:d9:dd:c25:c25:94de:f6e3
1152c19:dd:d9:dd:c25:c25:94de:f6e4/1272c19:dd:d9:dd:c25:c25:94de:f6e5
1162c19:dd:d9:dd:c25:c25:94de:f6e6/1272c19:dd:d9:dd:c25:c25:94de:f6e7
1172c19:dd:d9:dd:c25:c25:94de:f6e8/1272c19:dd:d9:dd:c25:c25:94de:f6e9
1182c19:dd:d9:dd:c25:c25:94de:f6ea/1272c19:dd:d9:dd:c25:c25:94de:f6eb
1192c19:dd:d9:dd:c25:c25:94de:f6ec/1272c19:dd:d9:dd:c25:c25:94de:f6ed
1202c19:dd:d9:dd:c25:c25:94de:f6ee/1272c19:dd:d9:dd:c25:c25:94de:f6ef
1212c19:dd:d9:dd:c25:c25:94de:f6f0/1272c19:dd:d9:dd:c25:c25:94de:f6f1
1222c19:dd:d9:dd:c25:c25:94de:f6f2/1272c19:dd:d9:dd:c25:c25:94de:f6f3
1232c19:dd:d9:dd:c25:c25:94de:f6f4/1272c19:dd:d9:dd:c25:c25:94de:f6f5
1242c19:dd:d9:dd:c25:c25:94de:f6f6/1272c19:dd:d9:dd:c25:c25:94de:f6f7
1252c19:dd:d9:dd:c25:c25:94de:f6f8/1272c19:dd:d9:dd:c25:c25:94de:f6f9
1262c19:dd:d9:dd:c25:c25:94de:f6fa/1272c19:dd:d9:dd:c25:c25:94de:f6fb
1272c19:dd:d9:dd:c25:c25:94de:f6fc/1272c19:dd:d9:dd:c25:c25:94de:f6fd
1282c19:dd:d9:dd:c25:c25:94de:f6fe/1272c19:dd:d9:dd:c25:c25:94de:f6ff
1292c19:dd:d9:dd:c25:c25:94de:f700/1272c19:dd:d9:dd:c25:c25:94de:f701
1302c19:dd:d9:dd:c25:c25:94de:f702/1272c19:dd:d9:dd:c25:c25:94de:f703
1312c19:dd:d9:dd:c25:c25:94de:f704/1272c19:dd:d9:dd:c25:c25:94de:f705
1322c19:dd:d9:dd:c25:c25:94de:f706/1272c19:dd:d9:dd:c25:c25:94de:f707
1332c19:dd:d9:dd:c25:c25:94de:f708/1272c19:dd:d9:dd:c25:c25:94de:f709
1342c19:dd:d9:dd:c25:c25:94de:f70a/1272c19:dd:d9:dd:c25:c25:94de:f70b
1352c19:dd:d9:dd:c25:c25:94de:f70c/1272c19:dd:d9:dd:c25:c25:94de:f70d
1362c19:dd:d9:dd:c25:c25:94de:f70e/1272c19:dd:d9:dd:c25:c25:94de:f70f
1372c19:dd:d9:dd:c25:c25:94de:f710/1272c19:dd:d9:dd:c25:c25:94de:f711
1382c19:dd:d9:dd:c25:c25:94de:f712/1272c19:dd:d9:dd:c25:c25:94de:f713
1392c19:dd:d9:dd:c25:c25:94de:f714/1272c19:dd:d9:dd:c25:c25:94de:f715
1402c19:dd:d9:dd:c25:c25:94de:f716/1272c19:dd:d9:dd:c25:c25:94de:f717
1412c19:dd:d9:dd:c25:c25:94de:f718/1272c19:dd:d9:dd:c25:c25:94de:f719
1422c19:dd:d9:dd:c25:c25:94de:f71a/1272c19:dd:d9:dd:c25:c25:94de:f71b
1432c19:dd:d9:dd:c25:c25:94de:f71c/1272c19:dd:d9:dd:c25:c25:94de:f71d
1442c19:dd:d9:dd:c25:c25:94de:f71e/1272c19:dd:d9:dd:c25:c25:94de:f71f
1452c19:dd:d9:dd:c25:c25:94de:f720/1272c19:dd:d9:dd:c25:c25:94de:f721
1462c19:dd:d9:dd:c25:c25:94de:f722/1272c19:dd:d9:dd:c25:c25:94de:f723
1472c19:dd:d9:dd:c25:c25:94de:f724/1272c19:dd:d9:dd:c25:c25:94de:f725
1482c19:dd:d9:dd:c25:c25:94de:f726/1272c19:dd:d9:dd:c25:c25:94de:f727
1492c19:dd:d9:dd:c25:c25:94de:f728/1272c19:dd:d9:dd:c25:c25:94de:f729
1502c19:dd:d9:dd:c25:c25:94de:f72a/1272c19:dd:d9:dd:c25:c25:94de:f72b
1512c19:dd:d9:dd:c25:c25:94de:f72c/1272c19:dd:d9:dd:c25:c25:94de:f72d
1522c19:dd:d9:dd:c25:c25:94de:f72e/1272c19:dd:d9:dd:c25:c25:94de:f72f
1532c19:dd:d9:dd:c25:c25:94de:f730/1272c19:dd:d9:dd:c25:c25:94de:f731
1542c19:dd:d9:dd:c25:c25:94de:f732/1272c19:dd:d9:dd:c25:c25:94de:f733
1552c19:dd:d9:dd:c25:c25:94de:f734/1272c19:dd:d9:dd:c25:c25:94de:f735
1562c19:dd:d9:dd:c25:c25:94de:f736/1272c19:dd:d9:dd:c25:c25:94de:f737
1572c19:dd:d9:dd:c25:c25:94de:f738/1272c19:dd:d9:dd:c25:c25:94de:f739
1582c19:dd:d9:dd:c25:c25:94de:f73a/1272c19:dd:d9:dd:c25:c25:94de:f73b
1592c19:dd:d9:dd:c25:c25:94de:f73c/1272c19:dd:d9:dd:c25:c25:94de:f73d
1602c19:dd:d9:dd:c25:c25:94de:f73e/1272c19:dd:d9:dd:c25:c25:94de:f73f
1612c19:dd:d9:dd:c25:c25:94de:f740/1272c19:dd:d9:dd:c25:c25:94de:f741
1622c19:dd:d9:dd:c25:c25:94de:f742/1272c19:dd:d9:dd:c25:c25:94de:f743
1632c19:dd:d9:dd:c25:c25:94de:f744/1272c19:dd:d9:dd:c25:c25:94de:f745
1642c19:dd:d9:dd:c25:c25:94de:f746/1272c19:dd:d9:dd:c25:c25:94de:f747
1652c19:dd:d9:dd:c25:c25:94de:f748/1272c19:dd:d9:dd:c25:c25:94de:f749
1662c19:dd:d9:dd:c25:c25:94de:f74a/1272c19:dd:d9:dd:c25:c25:94de:f74b
1672c19:dd:d9:dd:c25:c25:94de:f74c/1272c19:dd:d9:dd:c25:c25:94de:f74d
1682c19:dd:d9:dd:c25:c25:94de:f74e/1272c19:dd:d9:dd:c25:c25:94de:f74f
1692c19:dd:d9:dd:c25:c25:94de:f750/1272c19:dd:d9:dd:c25:c25:94de:f751
1702c19:dd:d9:dd:c25:c25:94de:f752/1272c19:dd:d9:dd:c25:c25:94de:f753
1712c19:dd:d9:dd:c25:c25:94de:f754/1272c19:dd:d9:dd:c25:c25:94de:f755
1722c19:dd:d9:dd:c25:c25:94de:f756/1272c19:dd:d9:dd:c25:c25:94de:f757
1732c19:dd:d9:dd:c25:c25:94de:f758/1272c19:dd:d9:dd:c25:c25:94de:f759
1742c19:dd:d9:dd:c25:c25:94de:f75a/1272c19:dd:d9:dd:c25:c25:94de:f75b
1752c19:dd:d9:dd:c25:c25:94de:f75c/1272c19:dd:d9:dd:c25:c25:94de:f75d
1762c19:dd:d9:dd:c25:c25:94de:f75e/1272c19:dd:d9:dd:c25:c25:94de:f75f
1772c19:dd:d9:dd:c25:c25:94de:f760/1272c19:dd:d9:dd:c25:c25:94de:f761
1782c19:dd:d9:dd:c25:c25:94de:f762/1272c19:dd:d9:dd:c25:c25:94de:f763
1792c19:dd:d9:dd:c25:c25:94de:f764/1272c19:dd:d9:dd:c25:c25:94de:f765
1802c19:dd:d9:dd:c25:c25:94de:f766/1272c19:dd:d9:dd:c25:c25:94de:f767
1812c19:dd:d9:dd:c25:c25:94de:f768/1272c19:dd:d9:dd:c25:c25:94de:f769
1822c19:dd:d9:dd:c25:c25:94de:f76a/1272c19:dd:d9:dd:c25:c25:94de:f76b
1832c19:dd:d9:dd:c25:c25:94de:f76c/1272c19:dd:d9:dd:c25:c25:94de:f76d
1842c19:dd:d9:dd:c25:c25:94de:f76e/1272c19:dd:d9:dd:c25:c25:94de:f76f
1852c19:dd:d9:dd:c25:c25:94de:f770/1272c19:dd:d9:dd:c25:c25:94de:f771
1862c19:dd:d9:dd:c25:c25:94de:f772/1272c19:dd:d9:dd:c25:c25:94de:f773
1872c19:dd:d9:dd:c25:c25:94de:f774/1272c19:dd:d9:dd:c25:c25:94de:f775
1882c19:dd:d9:dd:c25:c25:94de:f776/1272c19:dd:d9:dd:c25:c25:94de:f777
1892c19:dd:d9:dd:c25:c25:94de:f778/1272c19:dd:d9:dd:c25:c25:94de:f779
1902c19:dd:d9:dd:c25:c25:94de:f77a/1272c19:dd:d9:dd:c25:c25:94de:f77b
1912c19:dd:d9:dd:c25:c25:94de:f77c/1272c19:dd:d9:dd:c25:c25:94de:f77d
1922c19:dd:d9:dd:c25:c25:94de:f77e/1272c19:dd:d9:dd:c25:c25:94de:f77f
1932c19:dd:d9:dd:c25:c25:94de:f780/1272c19:dd:d9:dd:c25:c25:94de:f781
1942c19:dd:d9:dd:c25:c25:94de:f782/1272c19:dd:d9:dd:c25:c25:94de:f783
1952c19:dd:d9:dd:c25:c25:94de:f784/1272c19:dd:d9:dd:c25:c25:94de:f785
1962c19:dd:d9:dd:c25:c25:94de:f786/1272c19:dd:d9:dd:c25:c25:94de:f787
1972c19:dd:d9:dd:c25:c25:94de:f788/1272c19:dd:d9:dd:c25:c25:94de:f789
1982c19:dd:d9:dd:c25:c25:94de:f78a/1272c19:dd:d9:dd:c25:c25:94de:f78b
1992c19:dd:d9:dd:c25:c25:94de:f78c/1272c19:dd:d9:dd:c25:c25:94de:f78d
2002c19:dd:d9:dd:c25:c25:94de:f78e/1272c19:dd:d9:dd:c25:c25:94de:f78f
2012c19:dd:d9:dd:c25:c25:94de:f790/1272c19:dd:d9:dd:c25:c25:94de:f791
2022c19:dd:d9:dd:c25:c25:94de:f792/1272c19:dd:d9:dd:c25:c25:94de:f793
2032c19:dd:d9:dd:c25:c25:94de:f794/1272c19:dd:d9:dd:c25:c25:94de:f795
2042c19:dd:d9:dd:c25:c25:94de:f796/1272c19:dd:d9:dd:c25:c25:94de:f797
2052c19:dd:d9:dd:c25:c25:94de:f798/1272c19:dd:d9:dd:c25:c25:94de:f799
2062c19:dd:d9:dd:c25:c25:94de:f79a/1272c19:dd:d9:dd:c25:c25:94de:f79b
2072c19:dd:d9:dd:c25:c25:94de:f79c/1272c19:dd:d9:dd:c25:c25:94de:f79d
2082c19:dd:d9:dd:c25:c25:94de:f79e/1272c19:dd:d9:dd:c25:c25:94de:f79f
2092c19:dd:d9:dd:c25:c25:94de:f7a0/1272c19:dd:d9:dd:c25:c25:94de:f7a1
2102c19:dd:d9:dd:c25:c25:94de:f7a2/1272c19:dd:d9:dd:c25:c25:94de:f7a3
2112c19:dd:d9:dd:c25:c25:94de:f7a4/1272c19:dd:d9:dd:c25:c25:94de:f7a5
2122c19:dd:d9:dd:c25:c25:94de:f7a6/1272c19:dd:d9:dd:c25:c25:94de:f7a7
2132c19:dd:d9:dd:c25:c25:94de:f7a8/1272c19:dd:d9:dd:c25:c25:94de:f7a9
2142c19:dd:d9:dd:c25:c25:94de:f7aa/1272c19:dd:d9:dd:c25:c25:94de:f7ab
2152c19:dd:d9:dd:c25:c25:94de:f7ac/1272c19:dd:d9:dd:c25:c25:94de:f7ad
2162c19:dd:d9:dd:c25:c25:94de:f7ae/1272c19:dd:d9:dd:c25:c25:94de:f7af
2172c19:dd:d9:dd:c25:c25:94de:f7b0/1272c19:dd:d9:dd:c25:c25:94de:f7b1
2182c19:dd:d9:dd:c25:c25:94de:f7b2/1272c19:dd:d9:dd:c25:c25:94de:f7b3
2192c19:dd:d9:dd:c25:c25:94de:f7b4/1272c19:dd:d9:dd:c25:c25:94de:f7b5
2202c19:dd:d9:dd:c25:c25:94de:f7b6/1272c19:dd:d9:dd:c25:c25:94de:f7b7
2212c19:dd:d9:dd:c25:c25:94de:f7b8/1272c19:dd:d9:dd:c25:c25:94de:f7b9
2222c19:dd:d9:dd:c25:c25:94de:f7ba/1272c19:dd:d9:dd:c25:c25:94de:f7bb
2232c19:dd:d9:dd:c25:c25:94de:f7bc/1272c19:dd:d9:dd:c25:c25:94de:f7bd
2242c19:dd:d9:dd:c25:c25:94de:f7be/1272c19:dd:d9:dd:c25:c25:94de:f7bf
2252c19:dd:d9:dd:c25:c25:94de:f7c0/1272c19:dd:d9:dd:c25:c25:94de:f7c1
2262c19:dd:d9:dd:c25:c25:94de:f7c2/1272c19:dd:d9:dd:c25:c25:94de:f7c3
2272c19:dd:d9:dd:c25:c25:94de:f7c4/1272c19:dd:d9:dd:c25:c25:94de:f7c5
2282c19:dd:d9:dd:c25:c25:94de:f7c6/1272c19:dd:d9:dd:c25:c25:94de:f7c7
2292c19:dd:d9:dd:c25:c25:94de:f7c8/1272c19:dd:d9:dd:c25:c25:94de:f7c9
2302c19:dd:d9:dd:c25:c25:94de:f7ca/1272c19:dd:d9:dd:c25:c25:94de:f7cb
2312c19:dd:d9:dd:c25:c25:94de:f7cc/1272c19:dd:d9:dd:c25:c25:94de:f7cd
2322c19:dd:d9:dd:c25:c25:94de:f7ce/1272c19:dd:d9:dd:c25:c25:94de:f7cf
2332c19:dd:d9:dd:c25:c25:94de:f7d0/1272c19:dd:d9:dd:c25:c25:94de:f7d1
2342c19:dd:d9:dd:c25:c25:94de:f7d2/1272c19:dd:d9:dd:c25:c25:94de:f7d3
2352c19:dd:d9:dd:c25:c25:94de:f7d4/1272c19:dd:d9:dd:c25:c25:94de:f7d5
2362c19:dd:d9:dd:c25:c25:94de:f7d6/1272c19:dd:d9:dd:c25:c25:94de:f7d7
2372c19:dd:d9:dd:c25:c25:94de:f7d8/1272c19:dd:d9:dd:c25:c25:94de:f7d9
2382c19:dd:d9:dd:c25:c25:94de:f7da/1272c19:dd:d9:dd:c25:c25:94de:f7db
2392c19:dd:d9:dd:c25:c25:94de:f7dc/1272c19:dd:d9:dd:c25:c25:94de:f7dd
2402c19:dd:d9:dd:c25:c25:94de:f7de/1272c19:dd:d9:dd:c25:c25:94de:f7df
2412c19:dd:d9:dd:c25:c25:94de:f7e0/1272c19:dd:d9:dd:c25:c25:94de:f7e1
2422c19:dd:d9:dd:c25:c25:94de:f7e2/1272c19:dd:d9:dd:c25:c25:94de:f7e3
2432c19:dd:d9:dd:c25:c25:94de:f7e4/1272c19:dd:d9:dd:c25:c25:94de:f7e5
2442c19:dd:d9:dd:c25:c25:94de:f7e6/1272c19:dd:d9:dd:c25:c25:94de:f7e7
2452c19:dd:d9:dd:c25:c25:94de:f7e8/1272c19:dd:d9:dd:c25:c25:94de:f7e9
2462c19:dd:d9:dd:c25:c25:94de:f7ea/1272c19:dd:d9:dd:c25:c25:94de:f7eb
2472c19:dd:d9:dd:c25:c25:94de:f7ec/1272c19:dd:d9:dd:c25:c25:94de:f7ed
2482c19:dd:d9:dd:c25:c25:94de:f7ee/1272c19:dd:d9:dd:c25:c25:94de:f7ef
2492c19:dd:d9:dd:c25:c25:94de:f7f0/1272c19:dd:d9:dd:c25:c25:94de:f7f1
2502c19:dd:d9:dd:c25:c25:94de:f7f2/1272c19:dd:d9:dd:c25:c25:94de:f7f3
2512c19:dd:d9:dd:c25:c25:94de:f7f4/1272c19:dd:d9:dd:c25:c25:94de:f7f5
2522c19:dd:d9:dd:c25:c25:94de:f7f6/1272c19:dd:d9:dd:c25:c25:94de:f7f7
2532c19:dd:d9:dd:c25:c25:94de:f7f8/1272c19:dd:d9:dd:c25:c25:94de:f7f9
2542c19:dd:d9:dd:c25:c25:94de:f7fa/1272c19:dd:d9:dd:c25:c25:94de:f7fb
2552c19:dd:d9:dd:c25:c25:94de:f7fc/1272c19:dd:d9:dd:c25:c25:94de:f7fd
2562c19:dd:d9:dd:c25:c25:94de:f7fe/1272c19:dd:d9:dd:c25:c25:94de:f7ff

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.