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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:e600/119
First address
2c19:dd:d9:dd:c25:c25:94de:e600
Last address
2c19:dd:d9:dd:c25:c25:94de:e7ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:e600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
6.e.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.e.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:e600/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:e600/1272c19:dd:d9:dd:c25:c25:94de:e601
22c19:dd:d9:dd:c25:c25:94de:e602/1272c19:dd:d9:dd:c25:c25:94de:e603
32c19:dd:d9:dd:c25:c25:94de:e604/1272c19:dd:d9:dd:c25:c25:94de:e605
42c19:dd:d9:dd:c25:c25:94de:e606/1272c19:dd:d9:dd:c25:c25:94de:e607
52c19:dd:d9:dd:c25:c25:94de:e608/1272c19:dd:d9:dd:c25:c25:94de:e609
62c19:dd:d9:dd:c25:c25:94de:e60a/1272c19:dd:d9:dd:c25:c25:94de:e60b
72c19:dd:d9:dd:c25:c25:94de:e60c/1272c19:dd:d9:dd:c25:c25:94de:e60d
82c19:dd:d9:dd:c25:c25:94de:e60e/1272c19:dd:d9:dd:c25:c25:94de:e60f
92c19:dd:d9:dd:c25:c25:94de:e610/1272c19:dd:d9:dd:c25:c25:94de:e611
102c19:dd:d9:dd:c25:c25:94de:e612/1272c19:dd:d9:dd:c25:c25:94de:e613
112c19:dd:d9:dd:c25:c25:94de:e614/1272c19:dd:d9:dd:c25:c25:94de:e615
122c19:dd:d9:dd:c25:c25:94de:e616/1272c19:dd:d9:dd:c25:c25:94de:e617
132c19:dd:d9:dd:c25:c25:94de:e618/1272c19:dd:d9:dd:c25:c25:94de:e619
142c19:dd:d9:dd:c25:c25:94de:e61a/1272c19:dd:d9:dd:c25:c25:94de:e61b
152c19:dd:d9:dd:c25:c25:94de:e61c/1272c19:dd:d9:dd:c25:c25:94de:e61d
162c19:dd:d9:dd:c25:c25:94de:e61e/1272c19:dd:d9:dd:c25:c25:94de:e61f
172c19:dd:d9:dd:c25:c25:94de:e620/1272c19:dd:d9:dd:c25:c25:94de:e621
182c19:dd:d9:dd:c25:c25:94de:e622/1272c19:dd:d9:dd:c25:c25:94de:e623
192c19:dd:d9:dd:c25:c25:94de:e624/1272c19:dd:d9:dd:c25:c25:94de:e625
202c19:dd:d9:dd:c25:c25:94de:e626/1272c19:dd:d9:dd:c25:c25:94de:e627
212c19:dd:d9:dd:c25:c25:94de:e628/1272c19:dd:d9:dd:c25:c25:94de:e629
222c19:dd:d9:dd:c25:c25:94de:e62a/1272c19:dd:d9:dd:c25:c25:94de:e62b
232c19:dd:d9:dd:c25:c25:94de:e62c/1272c19:dd:d9:dd:c25:c25:94de:e62d
242c19:dd:d9:dd:c25:c25:94de:e62e/1272c19:dd:d9:dd:c25:c25:94de:e62f
252c19:dd:d9:dd:c25:c25:94de:e630/1272c19:dd:d9:dd:c25:c25:94de:e631
262c19:dd:d9:dd:c25:c25:94de:e632/1272c19:dd:d9:dd:c25:c25:94de:e633
272c19:dd:d9:dd:c25:c25:94de:e634/1272c19:dd:d9:dd:c25:c25:94de:e635
282c19:dd:d9:dd:c25:c25:94de:e636/1272c19:dd:d9:dd:c25:c25:94de:e637
292c19:dd:d9:dd:c25:c25:94de:e638/1272c19:dd:d9:dd:c25:c25:94de:e639
302c19:dd:d9:dd:c25:c25:94de:e63a/1272c19:dd:d9:dd:c25:c25:94de:e63b
312c19:dd:d9:dd:c25:c25:94de:e63c/1272c19:dd:d9:dd:c25:c25:94de:e63d
322c19:dd:d9:dd:c25:c25:94de:e63e/1272c19:dd:d9:dd:c25:c25:94de:e63f
332c19:dd:d9:dd:c25:c25:94de:e640/1272c19:dd:d9:dd:c25:c25:94de:e641
342c19:dd:d9:dd:c25:c25:94de:e642/1272c19:dd:d9:dd:c25:c25:94de:e643
352c19:dd:d9:dd:c25:c25:94de:e644/1272c19:dd:d9:dd:c25:c25:94de:e645
362c19:dd:d9:dd:c25:c25:94de:e646/1272c19:dd:d9:dd:c25:c25:94de:e647
372c19:dd:d9:dd:c25:c25:94de:e648/1272c19:dd:d9:dd:c25:c25:94de:e649
382c19:dd:d9:dd:c25:c25:94de:e64a/1272c19:dd:d9:dd:c25:c25:94de:e64b
392c19:dd:d9:dd:c25:c25:94de:e64c/1272c19:dd:d9:dd:c25:c25:94de:e64d
402c19:dd:d9:dd:c25:c25:94de:e64e/1272c19:dd:d9:dd:c25:c25:94de:e64f
412c19:dd:d9:dd:c25:c25:94de:e650/1272c19:dd:d9:dd:c25:c25:94de:e651
422c19:dd:d9:dd:c25:c25:94de:e652/1272c19:dd:d9:dd:c25:c25:94de:e653
432c19:dd:d9:dd:c25:c25:94de:e654/1272c19:dd:d9:dd:c25:c25:94de:e655
442c19:dd:d9:dd:c25:c25:94de:e656/1272c19:dd:d9:dd:c25:c25:94de:e657
452c19:dd:d9:dd:c25:c25:94de:e658/1272c19:dd:d9:dd:c25:c25:94de:e659
462c19:dd:d9:dd:c25:c25:94de:e65a/1272c19:dd:d9:dd:c25:c25:94de:e65b
472c19:dd:d9:dd:c25:c25:94de:e65c/1272c19:dd:d9:dd:c25:c25:94de:e65d
482c19:dd:d9:dd:c25:c25:94de:e65e/1272c19:dd:d9:dd:c25:c25:94de:e65f
492c19:dd:d9:dd:c25:c25:94de:e660/1272c19:dd:d9:dd:c25:c25:94de:e661
502c19:dd:d9:dd:c25:c25:94de:e662/1272c19:dd:d9:dd:c25:c25:94de:e663
512c19:dd:d9:dd:c25:c25:94de:e664/1272c19:dd:d9:dd:c25:c25:94de:e665
522c19:dd:d9:dd:c25:c25:94de:e666/1272c19:dd:d9:dd:c25:c25:94de:e667
532c19:dd:d9:dd:c25:c25:94de:e668/1272c19:dd:d9:dd:c25:c25:94de:e669
542c19:dd:d9:dd:c25:c25:94de:e66a/1272c19:dd:d9:dd:c25:c25:94de:e66b
552c19:dd:d9:dd:c25:c25:94de:e66c/1272c19:dd:d9:dd:c25:c25:94de:e66d
562c19:dd:d9:dd:c25:c25:94de:e66e/1272c19:dd:d9:dd:c25:c25:94de:e66f
572c19:dd:d9:dd:c25:c25:94de:e670/1272c19:dd:d9:dd:c25:c25:94de:e671
582c19:dd:d9:dd:c25:c25:94de:e672/1272c19:dd:d9:dd:c25:c25:94de:e673
592c19:dd:d9:dd:c25:c25:94de:e674/1272c19:dd:d9:dd:c25:c25:94de:e675
602c19:dd:d9:dd:c25:c25:94de:e676/1272c19:dd:d9:dd:c25:c25:94de:e677
612c19:dd:d9:dd:c25:c25:94de:e678/1272c19:dd:d9:dd:c25:c25:94de:e679
622c19:dd:d9:dd:c25:c25:94de:e67a/1272c19:dd:d9:dd:c25:c25:94de:e67b
632c19:dd:d9:dd:c25:c25:94de:e67c/1272c19:dd:d9:dd:c25:c25:94de:e67d
642c19:dd:d9:dd:c25:c25:94de:e67e/1272c19:dd:d9:dd:c25:c25:94de:e67f
652c19:dd:d9:dd:c25:c25:94de:e680/1272c19:dd:d9:dd:c25:c25:94de:e681
662c19:dd:d9:dd:c25:c25:94de:e682/1272c19:dd:d9:dd:c25:c25:94de:e683
672c19:dd:d9:dd:c25:c25:94de:e684/1272c19:dd:d9:dd:c25:c25:94de:e685
682c19:dd:d9:dd:c25:c25:94de:e686/1272c19:dd:d9:dd:c25:c25:94de:e687
692c19:dd:d9:dd:c25:c25:94de:e688/1272c19:dd:d9:dd:c25:c25:94de:e689
702c19:dd:d9:dd:c25:c25:94de:e68a/1272c19:dd:d9:dd:c25:c25:94de:e68b
712c19:dd:d9:dd:c25:c25:94de:e68c/1272c19:dd:d9:dd:c25:c25:94de:e68d
722c19:dd:d9:dd:c25:c25:94de:e68e/1272c19:dd:d9:dd:c25:c25:94de:e68f
732c19:dd:d9:dd:c25:c25:94de:e690/1272c19:dd:d9:dd:c25:c25:94de:e691
742c19:dd:d9:dd:c25:c25:94de:e692/1272c19:dd:d9:dd:c25:c25:94de:e693
752c19:dd:d9:dd:c25:c25:94de:e694/1272c19:dd:d9:dd:c25:c25:94de:e695
762c19:dd:d9:dd:c25:c25:94de:e696/1272c19:dd:d9:dd:c25:c25:94de:e697
772c19:dd:d9:dd:c25:c25:94de:e698/1272c19:dd:d9:dd:c25:c25:94de:e699
782c19:dd:d9:dd:c25:c25:94de:e69a/1272c19:dd:d9:dd:c25:c25:94de:e69b
792c19:dd:d9:dd:c25:c25:94de:e69c/1272c19:dd:d9:dd:c25:c25:94de:e69d
802c19:dd:d9:dd:c25:c25:94de:e69e/1272c19:dd:d9:dd:c25:c25:94de:e69f
812c19:dd:d9:dd:c25:c25:94de:e6a0/1272c19:dd:d9:dd:c25:c25:94de:e6a1
822c19:dd:d9:dd:c25:c25:94de:e6a2/1272c19:dd:d9:dd:c25:c25:94de:e6a3
832c19:dd:d9:dd:c25:c25:94de:e6a4/1272c19:dd:d9:dd:c25:c25:94de:e6a5
842c19:dd:d9:dd:c25:c25:94de:e6a6/1272c19:dd:d9:dd:c25:c25:94de:e6a7
852c19:dd:d9:dd:c25:c25:94de:e6a8/1272c19:dd:d9:dd:c25:c25:94de:e6a9
862c19:dd:d9:dd:c25:c25:94de:e6aa/1272c19:dd:d9:dd:c25:c25:94de:e6ab
872c19:dd:d9:dd:c25:c25:94de:e6ac/1272c19:dd:d9:dd:c25:c25:94de:e6ad
882c19:dd:d9:dd:c25:c25:94de:e6ae/1272c19:dd:d9:dd:c25:c25:94de:e6af
892c19:dd:d9:dd:c25:c25:94de:e6b0/1272c19:dd:d9:dd:c25:c25:94de:e6b1
902c19:dd:d9:dd:c25:c25:94de:e6b2/1272c19:dd:d9:dd:c25:c25:94de:e6b3
912c19:dd:d9:dd:c25:c25:94de:e6b4/1272c19:dd:d9:dd:c25:c25:94de:e6b5
922c19:dd:d9:dd:c25:c25:94de:e6b6/1272c19:dd:d9:dd:c25:c25:94de:e6b7
932c19:dd:d9:dd:c25:c25:94de:e6b8/1272c19:dd:d9:dd:c25:c25:94de:e6b9
942c19:dd:d9:dd:c25:c25:94de:e6ba/1272c19:dd:d9:dd:c25:c25:94de:e6bb
952c19:dd:d9:dd:c25:c25:94de:e6bc/1272c19:dd:d9:dd:c25:c25:94de:e6bd
962c19:dd:d9:dd:c25:c25:94de:e6be/1272c19:dd:d9:dd:c25:c25:94de:e6bf
972c19:dd:d9:dd:c25:c25:94de:e6c0/1272c19:dd:d9:dd:c25:c25:94de:e6c1
982c19:dd:d9:dd:c25:c25:94de:e6c2/1272c19:dd:d9:dd:c25:c25:94de:e6c3
992c19:dd:d9:dd:c25:c25:94de:e6c4/1272c19:dd:d9:dd:c25:c25:94de:e6c5
1002c19:dd:d9:dd:c25:c25:94de:e6c6/1272c19:dd:d9:dd:c25:c25:94de:e6c7
1012c19:dd:d9:dd:c25:c25:94de:e6c8/1272c19:dd:d9:dd:c25:c25:94de:e6c9
1022c19:dd:d9:dd:c25:c25:94de:e6ca/1272c19:dd:d9:dd:c25:c25:94de:e6cb
1032c19:dd:d9:dd:c25:c25:94de:e6cc/1272c19:dd:d9:dd:c25:c25:94de:e6cd
1042c19:dd:d9:dd:c25:c25:94de:e6ce/1272c19:dd:d9:dd:c25:c25:94de:e6cf
1052c19:dd:d9:dd:c25:c25:94de:e6d0/1272c19:dd:d9:dd:c25:c25:94de:e6d1
1062c19:dd:d9:dd:c25:c25:94de:e6d2/1272c19:dd:d9:dd:c25:c25:94de:e6d3
1072c19:dd:d9:dd:c25:c25:94de:e6d4/1272c19:dd:d9:dd:c25:c25:94de:e6d5
1082c19:dd:d9:dd:c25:c25:94de:e6d6/1272c19:dd:d9:dd:c25:c25:94de:e6d7
1092c19:dd:d9:dd:c25:c25:94de:e6d8/1272c19:dd:d9:dd:c25:c25:94de:e6d9
1102c19:dd:d9:dd:c25:c25:94de:e6da/1272c19:dd:d9:dd:c25:c25:94de:e6db
1112c19:dd:d9:dd:c25:c25:94de:e6dc/1272c19:dd:d9:dd:c25:c25:94de:e6dd
1122c19:dd:d9:dd:c25:c25:94de:e6de/1272c19:dd:d9:dd:c25:c25:94de:e6df
1132c19:dd:d9:dd:c25:c25:94de:e6e0/1272c19:dd:d9:dd:c25:c25:94de:e6e1
1142c19:dd:d9:dd:c25:c25:94de:e6e2/1272c19:dd:d9:dd:c25:c25:94de:e6e3
1152c19:dd:d9:dd:c25:c25:94de:e6e4/1272c19:dd:d9:dd:c25:c25:94de:e6e5
1162c19:dd:d9:dd:c25:c25:94de:e6e6/1272c19:dd:d9:dd:c25:c25:94de:e6e7
1172c19:dd:d9:dd:c25:c25:94de:e6e8/1272c19:dd:d9:dd:c25:c25:94de:e6e9
1182c19:dd:d9:dd:c25:c25:94de:e6ea/1272c19:dd:d9:dd:c25:c25:94de:e6eb
1192c19:dd:d9:dd:c25:c25:94de:e6ec/1272c19:dd:d9:dd:c25:c25:94de:e6ed
1202c19:dd:d9:dd:c25:c25:94de:e6ee/1272c19:dd:d9:dd:c25:c25:94de:e6ef
1212c19:dd:d9:dd:c25:c25:94de:e6f0/1272c19:dd:d9:dd:c25:c25:94de:e6f1
1222c19:dd:d9:dd:c25:c25:94de:e6f2/1272c19:dd:d9:dd:c25:c25:94de:e6f3
1232c19:dd:d9:dd:c25:c25:94de:e6f4/1272c19:dd:d9:dd:c25:c25:94de:e6f5
1242c19:dd:d9:dd:c25:c25:94de:e6f6/1272c19:dd:d9:dd:c25:c25:94de:e6f7
1252c19:dd:d9:dd:c25:c25:94de:e6f8/1272c19:dd:d9:dd:c25:c25:94de:e6f9
1262c19:dd:d9:dd:c25:c25:94de:e6fa/1272c19:dd:d9:dd:c25:c25:94de:e6fb
1272c19:dd:d9:dd:c25:c25:94de:e6fc/1272c19:dd:d9:dd:c25:c25:94de:e6fd
1282c19:dd:d9:dd:c25:c25:94de:e6fe/1272c19:dd:d9:dd:c25:c25:94de:e6ff
1292c19:dd:d9:dd:c25:c25:94de:e700/1272c19:dd:d9:dd:c25:c25:94de:e701
1302c19:dd:d9:dd:c25:c25:94de:e702/1272c19:dd:d9:dd:c25:c25:94de:e703
1312c19:dd:d9:dd:c25:c25:94de:e704/1272c19:dd:d9:dd:c25:c25:94de:e705
1322c19:dd:d9:dd:c25:c25:94de:e706/1272c19:dd:d9:dd:c25:c25:94de:e707
1332c19:dd:d9:dd:c25:c25:94de:e708/1272c19:dd:d9:dd:c25:c25:94de:e709
1342c19:dd:d9:dd:c25:c25:94de:e70a/1272c19:dd:d9:dd:c25:c25:94de:e70b
1352c19:dd:d9:dd:c25:c25:94de:e70c/1272c19:dd:d9:dd:c25:c25:94de:e70d
1362c19:dd:d9:dd:c25:c25:94de:e70e/1272c19:dd:d9:dd:c25:c25:94de:e70f
1372c19:dd:d9:dd:c25:c25:94de:e710/1272c19:dd:d9:dd:c25:c25:94de:e711
1382c19:dd:d9:dd:c25:c25:94de:e712/1272c19:dd:d9:dd:c25:c25:94de:e713
1392c19:dd:d9:dd:c25:c25:94de:e714/1272c19:dd:d9:dd:c25:c25:94de:e715
1402c19:dd:d9:dd:c25:c25:94de:e716/1272c19:dd:d9:dd:c25:c25:94de:e717
1412c19:dd:d9:dd:c25:c25:94de:e718/1272c19:dd:d9:dd:c25:c25:94de:e719
1422c19:dd:d9:dd:c25:c25:94de:e71a/1272c19:dd:d9:dd:c25:c25:94de:e71b
1432c19:dd:d9:dd:c25:c25:94de:e71c/1272c19:dd:d9:dd:c25:c25:94de:e71d
1442c19:dd:d9:dd:c25:c25:94de:e71e/1272c19:dd:d9:dd:c25:c25:94de:e71f
1452c19:dd:d9:dd:c25:c25:94de:e720/1272c19:dd:d9:dd:c25:c25:94de:e721
1462c19:dd:d9:dd:c25:c25:94de:e722/1272c19:dd:d9:dd:c25:c25:94de:e723
1472c19:dd:d9:dd:c25:c25:94de:e724/1272c19:dd:d9:dd:c25:c25:94de:e725
1482c19:dd:d9:dd:c25:c25:94de:e726/1272c19:dd:d9:dd:c25:c25:94de:e727
1492c19:dd:d9:dd:c25:c25:94de:e728/1272c19:dd:d9:dd:c25:c25:94de:e729
1502c19:dd:d9:dd:c25:c25:94de:e72a/1272c19:dd:d9:dd:c25:c25:94de:e72b
1512c19:dd:d9:dd:c25:c25:94de:e72c/1272c19:dd:d9:dd:c25:c25:94de:e72d
1522c19:dd:d9:dd:c25:c25:94de:e72e/1272c19:dd:d9:dd:c25:c25:94de:e72f
1532c19:dd:d9:dd:c25:c25:94de:e730/1272c19:dd:d9:dd:c25:c25:94de:e731
1542c19:dd:d9:dd:c25:c25:94de:e732/1272c19:dd:d9:dd:c25:c25:94de:e733
1552c19:dd:d9:dd:c25:c25:94de:e734/1272c19:dd:d9:dd:c25:c25:94de:e735
1562c19:dd:d9:dd:c25:c25:94de:e736/1272c19:dd:d9:dd:c25:c25:94de:e737
1572c19:dd:d9:dd:c25:c25:94de:e738/1272c19:dd:d9:dd:c25:c25:94de:e739
1582c19:dd:d9:dd:c25:c25:94de:e73a/1272c19:dd:d9:dd:c25:c25:94de:e73b
1592c19:dd:d9:dd:c25:c25:94de:e73c/1272c19:dd:d9:dd:c25:c25:94de:e73d
1602c19:dd:d9:dd:c25:c25:94de:e73e/1272c19:dd:d9:dd:c25:c25:94de:e73f
1612c19:dd:d9:dd:c25:c25:94de:e740/1272c19:dd:d9:dd:c25:c25:94de:e741
1622c19:dd:d9:dd:c25:c25:94de:e742/1272c19:dd:d9:dd:c25:c25:94de:e743
1632c19:dd:d9:dd:c25:c25:94de:e744/1272c19:dd:d9:dd:c25:c25:94de:e745
1642c19:dd:d9:dd:c25:c25:94de:e746/1272c19:dd:d9:dd:c25:c25:94de:e747
1652c19:dd:d9:dd:c25:c25:94de:e748/1272c19:dd:d9:dd:c25:c25:94de:e749
1662c19:dd:d9:dd:c25:c25:94de:e74a/1272c19:dd:d9:dd:c25:c25:94de:e74b
1672c19:dd:d9:dd:c25:c25:94de:e74c/1272c19:dd:d9:dd:c25:c25:94de:e74d
1682c19:dd:d9:dd:c25:c25:94de:e74e/1272c19:dd:d9:dd:c25:c25:94de:e74f
1692c19:dd:d9:dd:c25:c25:94de:e750/1272c19:dd:d9:dd:c25:c25:94de:e751
1702c19:dd:d9:dd:c25:c25:94de:e752/1272c19:dd:d9:dd:c25:c25:94de:e753
1712c19:dd:d9:dd:c25:c25:94de:e754/1272c19:dd:d9:dd:c25:c25:94de:e755
1722c19:dd:d9:dd:c25:c25:94de:e756/1272c19:dd:d9:dd:c25:c25:94de:e757
1732c19:dd:d9:dd:c25:c25:94de:e758/1272c19:dd:d9:dd:c25:c25:94de:e759
1742c19:dd:d9:dd:c25:c25:94de:e75a/1272c19:dd:d9:dd:c25:c25:94de:e75b
1752c19:dd:d9:dd:c25:c25:94de:e75c/1272c19:dd:d9:dd:c25:c25:94de:e75d
1762c19:dd:d9:dd:c25:c25:94de:e75e/1272c19:dd:d9:dd:c25:c25:94de:e75f
1772c19:dd:d9:dd:c25:c25:94de:e760/1272c19:dd:d9:dd:c25:c25:94de:e761
1782c19:dd:d9:dd:c25:c25:94de:e762/1272c19:dd:d9:dd:c25:c25:94de:e763
1792c19:dd:d9:dd:c25:c25:94de:e764/1272c19:dd:d9:dd:c25:c25:94de:e765
1802c19:dd:d9:dd:c25:c25:94de:e766/1272c19:dd:d9:dd:c25:c25:94de:e767
1812c19:dd:d9:dd:c25:c25:94de:e768/1272c19:dd:d9:dd:c25:c25:94de:e769
1822c19:dd:d9:dd:c25:c25:94de:e76a/1272c19:dd:d9:dd:c25:c25:94de:e76b
1832c19:dd:d9:dd:c25:c25:94de:e76c/1272c19:dd:d9:dd:c25:c25:94de:e76d
1842c19:dd:d9:dd:c25:c25:94de:e76e/1272c19:dd:d9:dd:c25:c25:94de:e76f
1852c19:dd:d9:dd:c25:c25:94de:e770/1272c19:dd:d9:dd:c25:c25:94de:e771
1862c19:dd:d9:dd:c25:c25:94de:e772/1272c19:dd:d9:dd:c25:c25:94de:e773
1872c19:dd:d9:dd:c25:c25:94de:e774/1272c19:dd:d9:dd:c25:c25:94de:e775
1882c19:dd:d9:dd:c25:c25:94de:e776/1272c19:dd:d9:dd:c25:c25:94de:e777
1892c19:dd:d9:dd:c25:c25:94de:e778/1272c19:dd:d9:dd:c25:c25:94de:e779
1902c19:dd:d9:dd:c25:c25:94de:e77a/1272c19:dd:d9:dd:c25:c25:94de:e77b
1912c19:dd:d9:dd:c25:c25:94de:e77c/1272c19:dd:d9:dd:c25:c25:94de:e77d
1922c19:dd:d9:dd:c25:c25:94de:e77e/1272c19:dd:d9:dd:c25:c25:94de:e77f
1932c19:dd:d9:dd:c25:c25:94de:e780/1272c19:dd:d9:dd:c25:c25:94de:e781
1942c19:dd:d9:dd:c25:c25:94de:e782/1272c19:dd:d9:dd:c25:c25:94de:e783
1952c19:dd:d9:dd:c25:c25:94de:e784/1272c19:dd:d9:dd:c25:c25:94de:e785
1962c19:dd:d9:dd:c25:c25:94de:e786/1272c19:dd:d9:dd:c25:c25:94de:e787
1972c19:dd:d9:dd:c25:c25:94de:e788/1272c19:dd:d9:dd:c25:c25:94de:e789
1982c19:dd:d9:dd:c25:c25:94de:e78a/1272c19:dd:d9:dd:c25:c25:94de:e78b
1992c19:dd:d9:dd:c25:c25:94de:e78c/1272c19:dd:d9:dd:c25:c25:94de:e78d
2002c19:dd:d9:dd:c25:c25:94de:e78e/1272c19:dd:d9:dd:c25:c25:94de:e78f
2012c19:dd:d9:dd:c25:c25:94de:e790/1272c19:dd:d9:dd:c25:c25:94de:e791
2022c19:dd:d9:dd:c25:c25:94de:e792/1272c19:dd:d9:dd:c25:c25:94de:e793
2032c19:dd:d9:dd:c25:c25:94de:e794/1272c19:dd:d9:dd:c25:c25:94de:e795
2042c19:dd:d9:dd:c25:c25:94de:e796/1272c19:dd:d9:dd:c25:c25:94de:e797
2052c19:dd:d9:dd:c25:c25:94de:e798/1272c19:dd:d9:dd:c25:c25:94de:e799
2062c19:dd:d9:dd:c25:c25:94de:e79a/1272c19:dd:d9:dd:c25:c25:94de:e79b
2072c19:dd:d9:dd:c25:c25:94de:e79c/1272c19:dd:d9:dd:c25:c25:94de:e79d
2082c19:dd:d9:dd:c25:c25:94de:e79e/1272c19:dd:d9:dd:c25:c25:94de:e79f
2092c19:dd:d9:dd:c25:c25:94de:e7a0/1272c19:dd:d9:dd:c25:c25:94de:e7a1
2102c19:dd:d9:dd:c25:c25:94de:e7a2/1272c19:dd:d9:dd:c25:c25:94de:e7a3
2112c19:dd:d9:dd:c25:c25:94de:e7a4/1272c19:dd:d9:dd:c25:c25:94de:e7a5
2122c19:dd:d9:dd:c25:c25:94de:e7a6/1272c19:dd:d9:dd:c25:c25:94de:e7a7
2132c19:dd:d9:dd:c25:c25:94de:e7a8/1272c19:dd:d9:dd:c25:c25:94de:e7a9
2142c19:dd:d9:dd:c25:c25:94de:e7aa/1272c19:dd:d9:dd:c25:c25:94de:e7ab
2152c19:dd:d9:dd:c25:c25:94de:e7ac/1272c19:dd:d9:dd:c25:c25:94de:e7ad
2162c19:dd:d9:dd:c25:c25:94de:e7ae/1272c19:dd:d9:dd:c25:c25:94de:e7af
2172c19:dd:d9:dd:c25:c25:94de:e7b0/1272c19:dd:d9:dd:c25:c25:94de:e7b1
2182c19:dd:d9:dd:c25:c25:94de:e7b2/1272c19:dd:d9:dd:c25:c25:94de:e7b3
2192c19:dd:d9:dd:c25:c25:94de:e7b4/1272c19:dd:d9:dd:c25:c25:94de:e7b5
2202c19:dd:d9:dd:c25:c25:94de:e7b6/1272c19:dd:d9:dd:c25:c25:94de:e7b7
2212c19:dd:d9:dd:c25:c25:94de:e7b8/1272c19:dd:d9:dd:c25:c25:94de:e7b9
2222c19:dd:d9:dd:c25:c25:94de:e7ba/1272c19:dd:d9:dd:c25:c25:94de:e7bb
2232c19:dd:d9:dd:c25:c25:94de:e7bc/1272c19:dd:d9:dd:c25:c25:94de:e7bd
2242c19:dd:d9:dd:c25:c25:94de:e7be/1272c19:dd:d9:dd:c25:c25:94de:e7bf
2252c19:dd:d9:dd:c25:c25:94de:e7c0/1272c19:dd:d9:dd:c25:c25:94de:e7c1
2262c19:dd:d9:dd:c25:c25:94de:e7c2/1272c19:dd:d9:dd:c25:c25:94de:e7c3
2272c19:dd:d9:dd:c25:c25:94de:e7c4/1272c19:dd:d9:dd:c25:c25:94de:e7c5
2282c19:dd:d9:dd:c25:c25:94de:e7c6/1272c19:dd:d9:dd:c25:c25:94de:e7c7
2292c19:dd:d9:dd:c25:c25:94de:e7c8/1272c19:dd:d9:dd:c25:c25:94de:e7c9
2302c19:dd:d9:dd:c25:c25:94de:e7ca/1272c19:dd:d9:dd:c25:c25:94de:e7cb
2312c19:dd:d9:dd:c25:c25:94de:e7cc/1272c19:dd:d9:dd:c25:c25:94de:e7cd
2322c19:dd:d9:dd:c25:c25:94de:e7ce/1272c19:dd:d9:dd:c25:c25:94de:e7cf
2332c19:dd:d9:dd:c25:c25:94de:e7d0/1272c19:dd:d9:dd:c25:c25:94de:e7d1
2342c19:dd:d9:dd:c25:c25:94de:e7d2/1272c19:dd:d9:dd:c25:c25:94de:e7d3
2352c19:dd:d9:dd:c25:c25:94de:e7d4/1272c19:dd:d9:dd:c25:c25:94de:e7d5
2362c19:dd:d9:dd:c25:c25:94de:e7d6/1272c19:dd:d9:dd:c25:c25:94de:e7d7
2372c19:dd:d9:dd:c25:c25:94de:e7d8/1272c19:dd:d9:dd:c25:c25:94de:e7d9
2382c19:dd:d9:dd:c25:c25:94de:e7da/1272c19:dd:d9:dd:c25:c25:94de:e7db
2392c19:dd:d9:dd:c25:c25:94de:e7dc/1272c19:dd:d9:dd:c25:c25:94de:e7dd
2402c19:dd:d9:dd:c25:c25:94de:e7de/1272c19:dd:d9:dd:c25:c25:94de:e7df
2412c19:dd:d9:dd:c25:c25:94de:e7e0/1272c19:dd:d9:dd:c25:c25:94de:e7e1
2422c19:dd:d9:dd:c25:c25:94de:e7e2/1272c19:dd:d9:dd:c25:c25:94de:e7e3
2432c19:dd:d9:dd:c25:c25:94de:e7e4/1272c19:dd:d9:dd:c25:c25:94de:e7e5
2442c19:dd:d9:dd:c25:c25:94de:e7e6/1272c19:dd:d9:dd:c25:c25:94de:e7e7
2452c19:dd:d9:dd:c25:c25:94de:e7e8/1272c19:dd:d9:dd:c25:c25:94de:e7e9
2462c19:dd:d9:dd:c25:c25:94de:e7ea/1272c19:dd:d9:dd:c25:c25:94de:e7eb
2472c19:dd:d9:dd:c25:c25:94de:e7ec/1272c19:dd:d9:dd:c25:c25:94de:e7ed
2482c19:dd:d9:dd:c25:c25:94de:e7ee/1272c19:dd:d9:dd:c25:c25:94de:e7ef
2492c19:dd:d9:dd:c25:c25:94de:e7f0/1272c19:dd:d9:dd:c25:c25:94de:e7f1
2502c19:dd:d9:dd:c25:c25:94de:e7f2/1272c19:dd:d9:dd:c25:c25:94de:e7f3
2512c19:dd:d9:dd:c25:c25:94de:e7f4/1272c19:dd:d9:dd:c25:c25:94de:e7f5
2522c19:dd:d9:dd:c25:c25:94de:e7f6/1272c19:dd:d9:dd:c25:c25:94de:e7f7
2532c19:dd:d9:dd:c25:c25:94de:e7f8/1272c19:dd:d9:dd:c25:c25:94de:e7f9
2542c19:dd:d9:dd:c25:c25:94de:e7fa/1272c19:dd:d9:dd:c25:c25:94de:e7fb
2552c19:dd:d9:dd:c25:c25:94de:e7fc/1272c19:dd:d9:dd:c25:c25:94de:e7fd
2562c19:dd:d9:dd:c25:c25:94de:e7fe/1272c19:dd:d9:dd:c25:c25:94de:e7ff

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.