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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:b600/119
First address
2c19:dd:d9:dd:c25:c25:94de:b600
Last address
2c19:dd:d9:dd:c25:c25:94de:b7ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:b600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
6.b.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.b.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:b600/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:b600/1272c19:dd:d9:dd:c25:c25:94de:b601
22c19:dd:d9:dd:c25:c25:94de:b602/1272c19:dd:d9:dd:c25:c25:94de:b603
32c19:dd:d9:dd:c25:c25:94de:b604/1272c19:dd:d9:dd:c25:c25:94de:b605
42c19:dd:d9:dd:c25:c25:94de:b606/1272c19:dd:d9:dd:c25:c25:94de:b607
52c19:dd:d9:dd:c25:c25:94de:b608/1272c19:dd:d9:dd:c25:c25:94de:b609
62c19:dd:d9:dd:c25:c25:94de:b60a/1272c19:dd:d9:dd:c25:c25:94de:b60b
72c19:dd:d9:dd:c25:c25:94de:b60c/1272c19:dd:d9:dd:c25:c25:94de:b60d
82c19:dd:d9:dd:c25:c25:94de:b60e/1272c19:dd:d9:dd:c25:c25:94de:b60f
92c19:dd:d9:dd:c25:c25:94de:b610/1272c19:dd:d9:dd:c25:c25:94de:b611
102c19:dd:d9:dd:c25:c25:94de:b612/1272c19:dd:d9:dd:c25:c25:94de:b613
112c19:dd:d9:dd:c25:c25:94de:b614/1272c19:dd:d9:dd:c25:c25:94de:b615
122c19:dd:d9:dd:c25:c25:94de:b616/1272c19:dd:d9:dd:c25:c25:94de:b617
132c19:dd:d9:dd:c25:c25:94de:b618/1272c19:dd:d9:dd:c25:c25:94de:b619
142c19:dd:d9:dd:c25:c25:94de:b61a/1272c19:dd:d9:dd:c25:c25:94de:b61b
152c19:dd:d9:dd:c25:c25:94de:b61c/1272c19:dd:d9:dd:c25:c25:94de:b61d
162c19:dd:d9:dd:c25:c25:94de:b61e/1272c19:dd:d9:dd:c25:c25:94de:b61f
172c19:dd:d9:dd:c25:c25:94de:b620/1272c19:dd:d9:dd:c25:c25:94de:b621
182c19:dd:d9:dd:c25:c25:94de:b622/1272c19:dd:d9:dd:c25:c25:94de:b623
192c19:dd:d9:dd:c25:c25:94de:b624/1272c19:dd:d9:dd:c25:c25:94de:b625
202c19:dd:d9:dd:c25:c25:94de:b626/1272c19:dd:d9:dd:c25:c25:94de:b627
212c19:dd:d9:dd:c25:c25:94de:b628/1272c19:dd:d9:dd:c25:c25:94de:b629
222c19:dd:d9:dd:c25:c25:94de:b62a/1272c19:dd:d9:dd:c25:c25:94de:b62b
232c19:dd:d9:dd:c25:c25:94de:b62c/1272c19:dd:d9:dd:c25:c25:94de:b62d
242c19:dd:d9:dd:c25:c25:94de:b62e/1272c19:dd:d9:dd:c25:c25:94de:b62f
252c19:dd:d9:dd:c25:c25:94de:b630/1272c19:dd:d9:dd:c25:c25:94de:b631
262c19:dd:d9:dd:c25:c25:94de:b632/1272c19:dd:d9:dd:c25:c25:94de:b633
272c19:dd:d9:dd:c25:c25:94de:b634/1272c19:dd:d9:dd:c25:c25:94de:b635
282c19:dd:d9:dd:c25:c25:94de:b636/1272c19:dd:d9:dd:c25:c25:94de:b637
292c19:dd:d9:dd:c25:c25:94de:b638/1272c19:dd:d9:dd:c25:c25:94de:b639
302c19:dd:d9:dd:c25:c25:94de:b63a/1272c19:dd:d9:dd:c25:c25:94de:b63b
312c19:dd:d9:dd:c25:c25:94de:b63c/1272c19:dd:d9:dd:c25:c25:94de:b63d
322c19:dd:d9:dd:c25:c25:94de:b63e/1272c19:dd:d9:dd:c25:c25:94de:b63f
332c19:dd:d9:dd:c25:c25:94de:b640/1272c19:dd:d9:dd:c25:c25:94de:b641
342c19:dd:d9:dd:c25:c25:94de:b642/1272c19:dd:d9:dd:c25:c25:94de:b643
352c19:dd:d9:dd:c25:c25:94de:b644/1272c19:dd:d9:dd:c25:c25:94de:b645
362c19:dd:d9:dd:c25:c25:94de:b646/1272c19:dd:d9:dd:c25:c25:94de:b647
372c19:dd:d9:dd:c25:c25:94de:b648/1272c19:dd:d9:dd:c25:c25:94de:b649
382c19:dd:d9:dd:c25:c25:94de:b64a/1272c19:dd:d9:dd:c25:c25:94de:b64b
392c19:dd:d9:dd:c25:c25:94de:b64c/1272c19:dd:d9:dd:c25:c25:94de:b64d
402c19:dd:d9:dd:c25:c25:94de:b64e/1272c19:dd:d9:dd:c25:c25:94de:b64f
412c19:dd:d9:dd:c25:c25:94de:b650/1272c19:dd:d9:dd:c25:c25:94de:b651
422c19:dd:d9:dd:c25:c25:94de:b652/1272c19:dd:d9:dd:c25:c25:94de:b653
432c19:dd:d9:dd:c25:c25:94de:b654/1272c19:dd:d9:dd:c25:c25:94de:b655
442c19:dd:d9:dd:c25:c25:94de:b656/1272c19:dd:d9:dd:c25:c25:94de:b657
452c19:dd:d9:dd:c25:c25:94de:b658/1272c19:dd:d9:dd:c25:c25:94de:b659
462c19:dd:d9:dd:c25:c25:94de:b65a/1272c19:dd:d9:dd:c25:c25:94de:b65b
472c19:dd:d9:dd:c25:c25:94de:b65c/1272c19:dd:d9:dd:c25:c25:94de:b65d
482c19:dd:d9:dd:c25:c25:94de:b65e/1272c19:dd:d9:dd:c25:c25:94de:b65f
492c19:dd:d9:dd:c25:c25:94de:b660/1272c19:dd:d9:dd:c25:c25:94de:b661
502c19:dd:d9:dd:c25:c25:94de:b662/1272c19:dd:d9:dd:c25:c25:94de:b663
512c19:dd:d9:dd:c25:c25:94de:b664/1272c19:dd:d9:dd:c25:c25:94de:b665
522c19:dd:d9:dd:c25:c25:94de:b666/1272c19:dd:d9:dd:c25:c25:94de:b667
532c19:dd:d9:dd:c25:c25:94de:b668/1272c19:dd:d9:dd:c25:c25:94de:b669
542c19:dd:d9:dd:c25:c25:94de:b66a/1272c19:dd:d9:dd:c25:c25:94de:b66b
552c19:dd:d9:dd:c25:c25:94de:b66c/1272c19:dd:d9:dd:c25:c25:94de:b66d
562c19:dd:d9:dd:c25:c25:94de:b66e/1272c19:dd:d9:dd:c25:c25:94de:b66f
572c19:dd:d9:dd:c25:c25:94de:b670/1272c19:dd:d9:dd:c25:c25:94de:b671
582c19:dd:d9:dd:c25:c25:94de:b672/1272c19:dd:d9:dd:c25:c25:94de:b673
592c19:dd:d9:dd:c25:c25:94de:b674/1272c19:dd:d9:dd:c25:c25:94de:b675
602c19:dd:d9:dd:c25:c25:94de:b676/1272c19:dd:d9:dd:c25:c25:94de:b677
612c19:dd:d9:dd:c25:c25:94de:b678/1272c19:dd:d9:dd:c25:c25:94de:b679
622c19:dd:d9:dd:c25:c25:94de:b67a/1272c19:dd:d9:dd:c25:c25:94de:b67b
632c19:dd:d9:dd:c25:c25:94de:b67c/1272c19:dd:d9:dd:c25:c25:94de:b67d
642c19:dd:d9:dd:c25:c25:94de:b67e/1272c19:dd:d9:dd:c25:c25:94de:b67f
652c19:dd:d9:dd:c25:c25:94de:b680/1272c19:dd:d9:dd:c25:c25:94de:b681
662c19:dd:d9:dd:c25:c25:94de:b682/1272c19:dd:d9:dd:c25:c25:94de:b683
672c19:dd:d9:dd:c25:c25:94de:b684/1272c19:dd:d9:dd:c25:c25:94de:b685
682c19:dd:d9:dd:c25:c25:94de:b686/1272c19:dd:d9:dd:c25:c25:94de:b687
692c19:dd:d9:dd:c25:c25:94de:b688/1272c19:dd:d9:dd:c25:c25:94de:b689
702c19:dd:d9:dd:c25:c25:94de:b68a/1272c19:dd:d9:dd:c25:c25:94de:b68b
712c19:dd:d9:dd:c25:c25:94de:b68c/1272c19:dd:d9:dd:c25:c25:94de:b68d
722c19:dd:d9:dd:c25:c25:94de:b68e/1272c19:dd:d9:dd:c25:c25:94de:b68f
732c19:dd:d9:dd:c25:c25:94de:b690/1272c19:dd:d9:dd:c25:c25:94de:b691
742c19:dd:d9:dd:c25:c25:94de:b692/1272c19:dd:d9:dd:c25:c25:94de:b693
752c19:dd:d9:dd:c25:c25:94de:b694/1272c19:dd:d9:dd:c25:c25:94de:b695
762c19:dd:d9:dd:c25:c25:94de:b696/1272c19:dd:d9:dd:c25:c25:94de:b697
772c19:dd:d9:dd:c25:c25:94de:b698/1272c19:dd:d9:dd:c25:c25:94de:b699
782c19:dd:d9:dd:c25:c25:94de:b69a/1272c19:dd:d9:dd:c25:c25:94de:b69b
792c19:dd:d9:dd:c25:c25:94de:b69c/1272c19:dd:d9:dd:c25:c25:94de:b69d
802c19:dd:d9:dd:c25:c25:94de:b69e/1272c19:dd:d9:dd:c25:c25:94de:b69f
812c19:dd:d9:dd:c25:c25:94de:b6a0/1272c19:dd:d9:dd:c25:c25:94de:b6a1
822c19:dd:d9:dd:c25:c25:94de:b6a2/1272c19:dd:d9:dd:c25:c25:94de:b6a3
832c19:dd:d9:dd:c25:c25:94de:b6a4/1272c19:dd:d9:dd:c25:c25:94de:b6a5
842c19:dd:d9:dd:c25:c25:94de:b6a6/1272c19:dd:d9:dd:c25:c25:94de:b6a7
852c19:dd:d9:dd:c25:c25:94de:b6a8/1272c19:dd:d9:dd:c25:c25:94de:b6a9
862c19:dd:d9:dd:c25:c25:94de:b6aa/1272c19:dd:d9:dd:c25:c25:94de:b6ab
872c19:dd:d9:dd:c25:c25:94de:b6ac/1272c19:dd:d9:dd:c25:c25:94de:b6ad
882c19:dd:d9:dd:c25:c25:94de:b6ae/1272c19:dd:d9:dd:c25:c25:94de:b6af
892c19:dd:d9:dd:c25:c25:94de:b6b0/1272c19:dd:d9:dd:c25:c25:94de:b6b1
902c19:dd:d9:dd:c25:c25:94de:b6b2/1272c19:dd:d9:dd:c25:c25:94de:b6b3
912c19:dd:d9:dd:c25:c25:94de:b6b4/1272c19:dd:d9:dd:c25:c25:94de:b6b5
922c19:dd:d9:dd:c25:c25:94de:b6b6/1272c19:dd:d9:dd:c25:c25:94de:b6b7
932c19:dd:d9:dd:c25:c25:94de:b6b8/1272c19:dd:d9:dd:c25:c25:94de:b6b9
942c19:dd:d9:dd:c25:c25:94de:b6ba/1272c19:dd:d9:dd:c25:c25:94de:b6bb
952c19:dd:d9:dd:c25:c25:94de:b6bc/1272c19:dd:d9:dd:c25:c25:94de:b6bd
962c19:dd:d9:dd:c25:c25:94de:b6be/1272c19:dd:d9:dd:c25:c25:94de:b6bf
972c19:dd:d9:dd:c25:c25:94de:b6c0/1272c19:dd:d9:dd:c25:c25:94de:b6c1
982c19:dd:d9:dd:c25:c25:94de:b6c2/1272c19:dd:d9:dd:c25:c25:94de:b6c3
992c19:dd:d9:dd:c25:c25:94de:b6c4/1272c19:dd:d9:dd:c25:c25:94de:b6c5
1002c19:dd:d9:dd:c25:c25:94de:b6c6/1272c19:dd:d9:dd:c25:c25:94de:b6c7
1012c19:dd:d9:dd:c25:c25:94de:b6c8/1272c19:dd:d9:dd:c25:c25:94de:b6c9
1022c19:dd:d9:dd:c25:c25:94de:b6ca/1272c19:dd:d9:dd:c25:c25:94de:b6cb
1032c19:dd:d9:dd:c25:c25:94de:b6cc/1272c19:dd:d9:dd:c25:c25:94de:b6cd
1042c19:dd:d9:dd:c25:c25:94de:b6ce/1272c19:dd:d9:dd:c25:c25:94de:b6cf
1052c19:dd:d9:dd:c25:c25:94de:b6d0/1272c19:dd:d9:dd:c25:c25:94de:b6d1
1062c19:dd:d9:dd:c25:c25:94de:b6d2/1272c19:dd:d9:dd:c25:c25:94de:b6d3
1072c19:dd:d9:dd:c25:c25:94de:b6d4/1272c19:dd:d9:dd:c25:c25:94de:b6d5
1082c19:dd:d9:dd:c25:c25:94de:b6d6/1272c19:dd:d9:dd:c25:c25:94de:b6d7
1092c19:dd:d9:dd:c25:c25:94de:b6d8/1272c19:dd:d9:dd:c25:c25:94de:b6d9
1102c19:dd:d9:dd:c25:c25:94de:b6da/1272c19:dd:d9:dd:c25:c25:94de:b6db
1112c19:dd:d9:dd:c25:c25:94de:b6dc/1272c19:dd:d9:dd:c25:c25:94de:b6dd
1122c19:dd:d9:dd:c25:c25:94de:b6de/1272c19:dd:d9:dd:c25:c25:94de:b6df
1132c19:dd:d9:dd:c25:c25:94de:b6e0/1272c19:dd:d9:dd:c25:c25:94de:b6e1
1142c19:dd:d9:dd:c25:c25:94de:b6e2/1272c19:dd:d9:dd:c25:c25:94de:b6e3
1152c19:dd:d9:dd:c25:c25:94de:b6e4/1272c19:dd:d9:dd:c25:c25:94de:b6e5
1162c19:dd:d9:dd:c25:c25:94de:b6e6/1272c19:dd:d9:dd:c25:c25:94de:b6e7
1172c19:dd:d9:dd:c25:c25:94de:b6e8/1272c19:dd:d9:dd:c25:c25:94de:b6e9
1182c19:dd:d9:dd:c25:c25:94de:b6ea/1272c19:dd:d9:dd:c25:c25:94de:b6eb
1192c19:dd:d9:dd:c25:c25:94de:b6ec/1272c19:dd:d9:dd:c25:c25:94de:b6ed
1202c19:dd:d9:dd:c25:c25:94de:b6ee/1272c19:dd:d9:dd:c25:c25:94de:b6ef
1212c19:dd:d9:dd:c25:c25:94de:b6f0/1272c19:dd:d9:dd:c25:c25:94de:b6f1
1222c19:dd:d9:dd:c25:c25:94de:b6f2/1272c19:dd:d9:dd:c25:c25:94de:b6f3
1232c19:dd:d9:dd:c25:c25:94de:b6f4/1272c19:dd:d9:dd:c25:c25:94de:b6f5
1242c19:dd:d9:dd:c25:c25:94de:b6f6/1272c19:dd:d9:dd:c25:c25:94de:b6f7
1252c19:dd:d9:dd:c25:c25:94de:b6f8/1272c19:dd:d9:dd:c25:c25:94de:b6f9
1262c19:dd:d9:dd:c25:c25:94de:b6fa/1272c19:dd:d9:dd:c25:c25:94de:b6fb
1272c19:dd:d9:dd:c25:c25:94de:b6fc/1272c19:dd:d9:dd:c25:c25:94de:b6fd
1282c19:dd:d9:dd:c25:c25:94de:b6fe/1272c19:dd:d9:dd:c25:c25:94de:b6ff
1292c19:dd:d9:dd:c25:c25:94de:b700/1272c19:dd:d9:dd:c25:c25:94de:b701
1302c19:dd:d9:dd:c25:c25:94de:b702/1272c19:dd:d9:dd:c25:c25:94de:b703
1312c19:dd:d9:dd:c25:c25:94de:b704/1272c19:dd:d9:dd:c25:c25:94de:b705
1322c19:dd:d9:dd:c25:c25:94de:b706/1272c19:dd:d9:dd:c25:c25:94de:b707
1332c19:dd:d9:dd:c25:c25:94de:b708/1272c19:dd:d9:dd:c25:c25:94de:b709
1342c19:dd:d9:dd:c25:c25:94de:b70a/1272c19:dd:d9:dd:c25:c25:94de:b70b
1352c19:dd:d9:dd:c25:c25:94de:b70c/1272c19:dd:d9:dd:c25:c25:94de:b70d
1362c19:dd:d9:dd:c25:c25:94de:b70e/1272c19:dd:d9:dd:c25:c25:94de:b70f
1372c19:dd:d9:dd:c25:c25:94de:b710/1272c19:dd:d9:dd:c25:c25:94de:b711
1382c19:dd:d9:dd:c25:c25:94de:b712/1272c19:dd:d9:dd:c25:c25:94de:b713
1392c19:dd:d9:dd:c25:c25:94de:b714/1272c19:dd:d9:dd:c25:c25:94de:b715
1402c19:dd:d9:dd:c25:c25:94de:b716/1272c19:dd:d9:dd:c25:c25:94de:b717
1412c19:dd:d9:dd:c25:c25:94de:b718/1272c19:dd:d9:dd:c25:c25:94de:b719
1422c19:dd:d9:dd:c25:c25:94de:b71a/1272c19:dd:d9:dd:c25:c25:94de:b71b
1432c19:dd:d9:dd:c25:c25:94de:b71c/1272c19:dd:d9:dd:c25:c25:94de:b71d
1442c19:dd:d9:dd:c25:c25:94de:b71e/1272c19:dd:d9:dd:c25:c25:94de:b71f
1452c19:dd:d9:dd:c25:c25:94de:b720/1272c19:dd:d9:dd:c25:c25:94de:b721
1462c19:dd:d9:dd:c25:c25:94de:b722/1272c19:dd:d9:dd:c25:c25:94de:b723
1472c19:dd:d9:dd:c25:c25:94de:b724/1272c19:dd:d9:dd:c25:c25:94de:b725
1482c19:dd:d9:dd:c25:c25:94de:b726/1272c19:dd:d9:dd:c25:c25:94de:b727
1492c19:dd:d9:dd:c25:c25:94de:b728/1272c19:dd:d9:dd:c25:c25:94de:b729
1502c19:dd:d9:dd:c25:c25:94de:b72a/1272c19:dd:d9:dd:c25:c25:94de:b72b
1512c19:dd:d9:dd:c25:c25:94de:b72c/1272c19:dd:d9:dd:c25:c25:94de:b72d
1522c19:dd:d9:dd:c25:c25:94de:b72e/1272c19:dd:d9:dd:c25:c25:94de:b72f
1532c19:dd:d9:dd:c25:c25:94de:b730/1272c19:dd:d9:dd:c25:c25:94de:b731
1542c19:dd:d9:dd:c25:c25:94de:b732/1272c19:dd:d9:dd:c25:c25:94de:b733
1552c19:dd:d9:dd:c25:c25:94de:b734/1272c19:dd:d9:dd:c25:c25:94de:b735
1562c19:dd:d9:dd:c25:c25:94de:b736/1272c19:dd:d9:dd:c25:c25:94de:b737
1572c19:dd:d9:dd:c25:c25:94de:b738/1272c19:dd:d9:dd:c25:c25:94de:b739
1582c19:dd:d9:dd:c25:c25:94de:b73a/1272c19:dd:d9:dd:c25:c25:94de:b73b
1592c19:dd:d9:dd:c25:c25:94de:b73c/1272c19:dd:d9:dd:c25:c25:94de:b73d
1602c19:dd:d9:dd:c25:c25:94de:b73e/1272c19:dd:d9:dd:c25:c25:94de:b73f
1612c19:dd:d9:dd:c25:c25:94de:b740/1272c19:dd:d9:dd:c25:c25:94de:b741
1622c19:dd:d9:dd:c25:c25:94de:b742/1272c19:dd:d9:dd:c25:c25:94de:b743
1632c19:dd:d9:dd:c25:c25:94de:b744/1272c19:dd:d9:dd:c25:c25:94de:b745
1642c19:dd:d9:dd:c25:c25:94de:b746/1272c19:dd:d9:dd:c25:c25:94de:b747
1652c19:dd:d9:dd:c25:c25:94de:b748/1272c19:dd:d9:dd:c25:c25:94de:b749
1662c19:dd:d9:dd:c25:c25:94de:b74a/1272c19:dd:d9:dd:c25:c25:94de:b74b
1672c19:dd:d9:dd:c25:c25:94de:b74c/1272c19:dd:d9:dd:c25:c25:94de:b74d
1682c19:dd:d9:dd:c25:c25:94de:b74e/1272c19:dd:d9:dd:c25:c25:94de:b74f
1692c19:dd:d9:dd:c25:c25:94de:b750/1272c19:dd:d9:dd:c25:c25:94de:b751
1702c19:dd:d9:dd:c25:c25:94de:b752/1272c19:dd:d9:dd:c25:c25:94de:b753
1712c19:dd:d9:dd:c25:c25:94de:b754/1272c19:dd:d9:dd:c25:c25:94de:b755
1722c19:dd:d9:dd:c25:c25:94de:b756/1272c19:dd:d9:dd:c25:c25:94de:b757
1732c19:dd:d9:dd:c25:c25:94de:b758/1272c19:dd:d9:dd:c25:c25:94de:b759
1742c19:dd:d9:dd:c25:c25:94de:b75a/1272c19:dd:d9:dd:c25:c25:94de:b75b
1752c19:dd:d9:dd:c25:c25:94de:b75c/1272c19:dd:d9:dd:c25:c25:94de:b75d
1762c19:dd:d9:dd:c25:c25:94de:b75e/1272c19:dd:d9:dd:c25:c25:94de:b75f
1772c19:dd:d9:dd:c25:c25:94de:b760/1272c19:dd:d9:dd:c25:c25:94de:b761
1782c19:dd:d9:dd:c25:c25:94de:b762/1272c19:dd:d9:dd:c25:c25:94de:b763
1792c19:dd:d9:dd:c25:c25:94de:b764/1272c19:dd:d9:dd:c25:c25:94de:b765
1802c19:dd:d9:dd:c25:c25:94de:b766/1272c19:dd:d9:dd:c25:c25:94de:b767
1812c19:dd:d9:dd:c25:c25:94de:b768/1272c19:dd:d9:dd:c25:c25:94de:b769
1822c19:dd:d9:dd:c25:c25:94de:b76a/1272c19:dd:d9:dd:c25:c25:94de:b76b
1832c19:dd:d9:dd:c25:c25:94de:b76c/1272c19:dd:d9:dd:c25:c25:94de:b76d
1842c19:dd:d9:dd:c25:c25:94de:b76e/1272c19:dd:d9:dd:c25:c25:94de:b76f
1852c19:dd:d9:dd:c25:c25:94de:b770/1272c19:dd:d9:dd:c25:c25:94de:b771
1862c19:dd:d9:dd:c25:c25:94de:b772/1272c19:dd:d9:dd:c25:c25:94de:b773
1872c19:dd:d9:dd:c25:c25:94de:b774/1272c19:dd:d9:dd:c25:c25:94de:b775
1882c19:dd:d9:dd:c25:c25:94de:b776/1272c19:dd:d9:dd:c25:c25:94de:b777
1892c19:dd:d9:dd:c25:c25:94de:b778/1272c19:dd:d9:dd:c25:c25:94de:b779
1902c19:dd:d9:dd:c25:c25:94de:b77a/1272c19:dd:d9:dd:c25:c25:94de:b77b
1912c19:dd:d9:dd:c25:c25:94de:b77c/1272c19:dd:d9:dd:c25:c25:94de:b77d
1922c19:dd:d9:dd:c25:c25:94de:b77e/1272c19:dd:d9:dd:c25:c25:94de:b77f
1932c19:dd:d9:dd:c25:c25:94de:b780/1272c19:dd:d9:dd:c25:c25:94de:b781
1942c19:dd:d9:dd:c25:c25:94de:b782/1272c19:dd:d9:dd:c25:c25:94de:b783
1952c19:dd:d9:dd:c25:c25:94de:b784/1272c19:dd:d9:dd:c25:c25:94de:b785
1962c19:dd:d9:dd:c25:c25:94de:b786/1272c19:dd:d9:dd:c25:c25:94de:b787
1972c19:dd:d9:dd:c25:c25:94de:b788/1272c19:dd:d9:dd:c25:c25:94de:b789
1982c19:dd:d9:dd:c25:c25:94de:b78a/1272c19:dd:d9:dd:c25:c25:94de:b78b
1992c19:dd:d9:dd:c25:c25:94de:b78c/1272c19:dd:d9:dd:c25:c25:94de:b78d
2002c19:dd:d9:dd:c25:c25:94de:b78e/1272c19:dd:d9:dd:c25:c25:94de:b78f
2012c19:dd:d9:dd:c25:c25:94de:b790/1272c19:dd:d9:dd:c25:c25:94de:b791
2022c19:dd:d9:dd:c25:c25:94de:b792/1272c19:dd:d9:dd:c25:c25:94de:b793
2032c19:dd:d9:dd:c25:c25:94de:b794/1272c19:dd:d9:dd:c25:c25:94de:b795
2042c19:dd:d9:dd:c25:c25:94de:b796/1272c19:dd:d9:dd:c25:c25:94de:b797
2052c19:dd:d9:dd:c25:c25:94de:b798/1272c19:dd:d9:dd:c25:c25:94de:b799
2062c19:dd:d9:dd:c25:c25:94de:b79a/1272c19:dd:d9:dd:c25:c25:94de:b79b
2072c19:dd:d9:dd:c25:c25:94de:b79c/1272c19:dd:d9:dd:c25:c25:94de:b79d
2082c19:dd:d9:dd:c25:c25:94de:b79e/1272c19:dd:d9:dd:c25:c25:94de:b79f
2092c19:dd:d9:dd:c25:c25:94de:b7a0/1272c19:dd:d9:dd:c25:c25:94de:b7a1
2102c19:dd:d9:dd:c25:c25:94de:b7a2/1272c19:dd:d9:dd:c25:c25:94de:b7a3
2112c19:dd:d9:dd:c25:c25:94de:b7a4/1272c19:dd:d9:dd:c25:c25:94de:b7a5
2122c19:dd:d9:dd:c25:c25:94de:b7a6/1272c19:dd:d9:dd:c25:c25:94de:b7a7
2132c19:dd:d9:dd:c25:c25:94de:b7a8/1272c19:dd:d9:dd:c25:c25:94de:b7a9
2142c19:dd:d9:dd:c25:c25:94de:b7aa/1272c19:dd:d9:dd:c25:c25:94de:b7ab
2152c19:dd:d9:dd:c25:c25:94de:b7ac/1272c19:dd:d9:dd:c25:c25:94de:b7ad
2162c19:dd:d9:dd:c25:c25:94de:b7ae/1272c19:dd:d9:dd:c25:c25:94de:b7af
2172c19:dd:d9:dd:c25:c25:94de:b7b0/1272c19:dd:d9:dd:c25:c25:94de:b7b1
2182c19:dd:d9:dd:c25:c25:94de:b7b2/1272c19:dd:d9:dd:c25:c25:94de:b7b3
2192c19:dd:d9:dd:c25:c25:94de:b7b4/1272c19:dd:d9:dd:c25:c25:94de:b7b5
2202c19:dd:d9:dd:c25:c25:94de:b7b6/1272c19:dd:d9:dd:c25:c25:94de:b7b7
2212c19:dd:d9:dd:c25:c25:94de:b7b8/1272c19:dd:d9:dd:c25:c25:94de:b7b9
2222c19:dd:d9:dd:c25:c25:94de:b7ba/1272c19:dd:d9:dd:c25:c25:94de:b7bb
2232c19:dd:d9:dd:c25:c25:94de:b7bc/1272c19:dd:d9:dd:c25:c25:94de:b7bd
2242c19:dd:d9:dd:c25:c25:94de:b7be/1272c19:dd:d9:dd:c25:c25:94de:b7bf
2252c19:dd:d9:dd:c25:c25:94de:b7c0/1272c19:dd:d9:dd:c25:c25:94de:b7c1
2262c19:dd:d9:dd:c25:c25:94de:b7c2/1272c19:dd:d9:dd:c25:c25:94de:b7c3
2272c19:dd:d9:dd:c25:c25:94de:b7c4/1272c19:dd:d9:dd:c25:c25:94de:b7c5
2282c19:dd:d9:dd:c25:c25:94de:b7c6/1272c19:dd:d9:dd:c25:c25:94de:b7c7
2292c19:dd:d9:dd:c25:c25:94de:b7c8/1272c19:dd:d9:dd:c25:c25:94de:b7c9
2302c19:dd:d9:dd:c25:c25:94de:b7ca/1272c19:dd:d9:dd:c25:c25:94de:b7cb
2312c19:dd:d9:dd:c25:c25:94de:b7cc/1272c19:dd:d9:dd:c25:c25:94de:b7cd
2322c19:dd:d9:dd:c25:c25:94de:b7ce/1272c19:dd:d9:dd:c25:c25:94de:b7cf
2332c19:dd:d9:dd:c25:c25:94de:b7d0/1272c19:dd:d9:dd:c25:c25:94de:b7d1
2342c19:dd:d9:dd:c25:c25:94de:b7d2/1272c19:dd:d9:dd:c25:c25:94de:b7d3
2352c19:dd:d9:dd:c25:c25:94de:b7d4/1272c19:dd:d9:dd:c25:c25:94de:b7d5
2362c19:dd:d9:dd:c25:c25:94de:b7d6/1272c19:dd:d9:dd:c25:c25:94de:b7d7
2372c19:dd:d9:dd:c25:c25:94de:b7d8/1272c19:dd:d9:dd:c25:c25:94de:b7d9
2382c19:dd:d9:dd:c25:c25:94de:b7da/1272c19:dd:d9:dd:c25:c25:94de:b7db
2392c19:dd:d9:dd:c25:c25:94de:b7dc/1272c19:dd:d9:dd:c25:c25:94de:b7dd
2402c19:dd:d9:dd:c25:c25:94de:b7de/1272c19:dd:d9:dd:c25:c25:94de:b7df
2412c19:dd:d9:dd:c25:c25:94de:b7e0/1272c19:dd:d9:dd:c25:c25:94de:b7e1
2422c19:dd:d9:dd:c25:c25:94de:b7e2/1272c19:dd:d9:dd:c25:c25:94de:b7e3
2432c19:dd:d9:dd:c25:c25:94de:b7e4/1272c19:dd:d9:dd:c25:c25:94de:b7e5
2442c19:dd:d9:dd:c25:c25:94de:b7e6/1272c19:dd:d9:dd:c25:c25:94de:b7e7
2452c19:dd:d9:dd:c25:c25:94de:b7e8/1272c19:dd:d9:dd:c25:c25:94de:b7e9
2462c19:dd:d9:dd:c25:c25:94de:b7ea/1272c19:dd:d9:dd:c25:c25:94de:b7eb
2472c19:dd:d9:dd:c25:c25:94de:b7ec/1272c19:dd:d9:dd:c25:c25:94de:b7ed
2482c19:dd:d9:dd:c25:c25:94de:b7ee/1272c19:dd:d9:dd:c25:c25:94de:b7ef
2492c19:dd:d9:dd:c25:c25:94de:b7f0/1272c19:dd:d9:dd:c25:c25:94de:b7f1
2502c19:dd:d9:dd:c25:c25:94de:b7f2/1272c19:dd:d9:dd:c25:c25:94de:b7f3
2512c19:dd:d9:dd:c25:c25:94de:b7f4/1272c19:dd:d9:dd:c25:c25:94de:b7f5
2522c19:dd:d9:dd:c25:c25:94de:b7f6/1272c19:dd:d9:dd:c25:c25:94de:b7f7
2532c19:dd:d9:dd:c25:c25:94de:b7f8/1272c19:dd:d9:dd:c25:c25:94de:b7f9
2542c19:dd:d9:dd:c25:c25:94de:b7fa/1272c19:dd:d9:dd:c25:c25:94de:b7fb
2552c19:dd:d9:dd:c25:c25:94de:b7fc/1272c19:dd:d9:dd:c25:c25:94de:b7fd
2562c19:dd:d9:dd:c25:c25:94de:b7fe/1272c19:dd:d9:dd:c25:c25:94de:b7ff

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.