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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Prefix/120
Addresses256
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:d915:e600/120
First address
2c19:dd:d9:dd:c25:c25:d915:e600
Last address
2c19:dd:d9:dd:c25:c25:d915:e6ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:e600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.e.5.1.9.d.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:d915:e600/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:e600/1282c19:dd:d9:dd:c25:c25:d915:e600
22c19:dd:d9:dd:c25:c25:d915:e601/1282c19:dd:d9:dd:c25:c25:d915:e601
32c19:dd:d9:dd:c25:c25:d915:e602/1282c19:dd:d9:dd:c25:c25:d915:e602
42c19:dd:d9:dd:c25:c25:d915:e603/1282c19:dd:d9:dd:c25:c25:d915:e603
52c19:dd:d9:dd:c25:c25:d915:e604/1282c19:dd:d9:dd:c25:c25:d915:e604
62c19:dd:d9:dd:c25:c25:d915:e605/1282c19:dd:d9:dd:c25:c25:d915:e605
72c19:dd:d9:dd:c25:c25:d915:e606/1282c19:dd:d9:dd:c25:c25:d915:e606
82c19:dd:d9:dd:c25:c25:d915:e607/1282c19:dd:d9:dd:c25:c25:d915:e607
92c19:dd:d9:dd:c25:c25:d915:e608/1282c19:dd:d9:dd:c25:c25:d915:e608
102c19:dd:d9:dd:c25:c25:d915:e609/1282c19:dd:d9:dd:c25:c25:d915:e609
112c19:dd:d9:dd:c25:c25:d915:e60a/1282c19:dd:d9:dd:c25:c25:d915:e60a
122c19:dd:d9:dd:c25:c25:d915:e60b/1282c19:dd:d9:dd:c25:c25:d915:e60b
132c19:dd:d9:dd:c25:c25:d915:e60c/1282c19:dd:d9:dd:c25:c25:d915:e60c
142c19:dd:d9:dd:c25:c25:d915:e60d/1282c19:dd:d9:dd:c25:c25:d915:e60d
152c19:dd:d9:dd:c25:c25:d915:e60e/1282c19:dd:d9:dd:c25:c25:d915:e60e
162c19:dd:d9:dd:c25:c25:d915:e60f/1282c19:dd:d9:dd:c25:c25:d915:e60f
172c19:dd:d9:dd:c25:c25:d915:e610/1282c19:dd:d9:dd:c25:c25:d915:e610
182c19:dd:d9:dd:c25:c25:d915:e611/1282c19:dd:d9:dd:c25:c25:d915:e611
192c19:dd:d9:dd:c25:c25:d915:e612/1282c19:dd:d9:dd:c25:c25:d915:e612
202c19:dd:d9:dd:c25:c25:d915:e613/1282c19:dd:d9:dd:c25:c25:d915:e613
212c19:dd:d9:dd:c25:c25:d915:e614/1282c19:dd:d9:dd:c25:c25:d915:e614
222c19:dd:d9:dd:c25:c25:d915:e615/1282c19:dd:d9:dd:c25:c25:d915:e615
232c19:dd:d9:dd:c25:c25:d915:e616/1282c19:dd:d9:dd:c25:c25:d915:e616
242c19:dd:d9:dd:c25:c25:d915:e617/1282c19:dd:d9:dd:c25:c25:d915:e617
252c19:dd:d9:dd:c25:c25:d915:e618/1282c19:dd:d9:dd:c25:c25:d915:e618
262c19:dd:d9:dd:c25:c25:d915:e619/1282c19:dd:d9:dd:c25:c25:d915:e619
272c19:dd:d9:dd:c25:c25:d915:e61a/1282c19:dd:d9:dd:c25:c25:d915:e61a
282c19:dd:d9:dd:c25:c25:d915:e61b/1282c19:dd:d9:dd:c25:c25:d915:e61b
292c19:dd:d9:dd:c25:c25:d915:e61c/1282c19:dd:d9:dd:c25:c25:d915:e61c
302c19:dd:d9:dd:c25:c25:d915:e61d/1282c19:dd:d9:dd:c25:c25:d915:e61d
312c19:dd:d9:dd:c25:c25:d915:e61e/1282c19:dd:d9:dd:c25:c25:d915:e61e
322c19:dd:d9:dd:c25:c25:d915:e61f/1282c19:dd:d9:dd:c25:c25:d915:e61f
332c19:dd:d9:dd:c25:c25:d915:e620/1282c19:dd:d9:dd:c25:c25:d915:e620
342c19:dd:d9:dd:c25:c25:d915:e621/1282c19:dd:d9:dd:c25:c25:d915:e621
352c19:dd:d9:dd:c25:c25:d915:e622/1282c19:dd:d9:dd:c25:c25:d915:e622
362c19:dd:d9:dd:c25:c25:d915:e623/1282c19:dd:d9:dd:c25:c25:d915:e623
372c19:dd:d9:dd:c25:c25:d915:e624/1282c19:dd:d9:dd:c25:c25:d915:e624
382c19:dd:d9:dd:c25:c25:d915:e625/1282c19:dd:d9:dd:c25:c25:d915:e625
392c19:dd:d9:dd:c25:c25:d915:e626/1282c19:dd:d9:dd:c25:c25:d915:e626
402c19:dd:d9:dd:c25:c25:d915:e627/1282c19:dd:d9:dd:c25:c25:d915:e627
412c19:dd:d9:dd:c25:c25:d915:e628/1282c19:dd:d9:dd:c25:c25:d915:e628
422c19:dd:d9:dd:c25:c25:d915:e629/1282c19:dd:d9:dd:c25:c25:d915:e629
432c19:dd:d9:dd:c25:c25:d915:e62a/1282c19:dd:d9:dd:c25:c25:d915:e62a
442c19:dd:d9:dd:c25:c25:d915:e62b/1282c19:dd:d9:dd:c25:c25:d915:e62b
452c19:dd:d9:dd:c25:c25:d915:e62c/1282c19:dd:d9:dd:c25:c25:d915:e62c
462c19:dd:d9:dd:c25:c25:d915:e62d/1282c19:dd:d9:dd:c25:c25:d915:e62d
472c19:dd:d9:dd:c25:c25:d915:e62e/1282c19:dd:d9:dd:c25:c25:d915:e62e
482c19:dd:d9:dd:c25:c25:d915:e62f/1282c19:dd:d9:dd:c25:c25:d915:e62f
492c19:dd:d9:dd:c25:c25:d915:e630/1282c19:dd:d9:dd:c25:c25:d915:e630
502c19:dd:d9:dd:c25:c25:d915:e631/1282c19:dd:d9:dd:c25:c25:d915:e631
512c19:dd:d9:dd:c25:c25:d915:e632/1282c19:dd:d9:dd:c25:c25:d915:e632
522c19:dd:d9:dd:c25:c25:d915:e633/1282c19:dd:d9:dd:c25:c25:d915:e633
532c19:dd:d9:dd:c25:c25:d915:e634/1282c19:dd:d9:dd:c25:c25:d915:e634
542c19:dd:d9:dd:c25:c25:d915:e635/1282c19:dd:d9:dd:c25:c25:d915:e635
552c19:dd:d9:dd:c25:c25:d915:e636/1282c19:dd:d9:dd:c25:c25:d915:e636
562c19:dd:d9:dd:c25:c25:d915:e637/1282c19:dd:d9:dd:c25:c25:d915:e637
572c19:dd:d9:dd:c25:c25:d915:e638/1282c19:dd:d9:dd:c25:c25:d915:e638
582c19:dd:d9:dd:c25:c25:d915:e639/1282c19:dd:d9:dd:c25:c25:d915:e639
592c19:dd:d9:dd:c25:c25:d915:e63a/1282c19:dd:d9:dd:c25:c25:d915:e63a
602c19:dd:d9:dd:c25:c25:d915:e63b/1282c19:dd:d9:dd:c25:c25:d915:e63b
612c19:dd:d9:dd:c25:c25:d915:e63c/1282c19:dd:d9:dd:c25:c25:d915:e63c
622c19:dd:d9:dd:c25:c25:d915:e63d/1282c19:dd:d9:dd:c25:c25:d915:e63d
632c19:dd:d9:dd:c25:c25:d915:e63e/1282c19:dd:d9:dd:c25:c25:d915:e63e
642c19:dd:d9:dd:c25:c25:d915:e63f/1282c19:dd:d9:dd:c25:c25:d915:e63f
652c19:dd:d9:dd:c25:c25:d915:e640/1282c19:dd:d9:dd:c25:c25:d915:e640
662c19:dd:d9:dd:c25:c25:d915:e641/1282c19:dd:d9:dd:c25:c25:d915:e641
672c19:dd:d9:dd:c25:c25:d915:e642/1282c19:dd:d9:dd:c25:c25:d915:e642
682c19:dd:d9:dd:c25:c25:d915:e643/1282c19:dd:d9:dd:c25:c25:d915:e643
692c19:dd:d9:dd:c25:c25:d915:e644/1282c19:dd:d9:dd:c25:c25:d915:e644
702c19:dd:d9:dd:c25:c25:d915:e645/1282c19:dd:d9:dd:c25:c25:d915:e645
712c19:dd:d9:dd:c25:c25:d915:e646/1282c19:dd:d9:dd:c25:c25:d915:e646
722c19:dd:d9:dd:c25:c25:d915:e647/1282c19:dd:d9:dd:c25:c25:d915:e647
732c19:dd:d9:dd:c25:c25:d915:e648/1282c19:dd:d9:dd:c25:c25:d915:e648
742c19:dd:d9:dd:c25:c25:d915:e649/1282c19:dd:d9:dd:c25:c25:d915:e649
752c19:dd:d9:dd:c25:c25:d915:e64a/1282c19:dd:d9:dd:c25:c25:d915:e64a
762c19:dd:d9:dd:c25:c25:d915:e64b/1282c19:dd:d9:dd:c25:c25:d915:e64b
772c19:dd:d9:dd:c25:c25:d915:e64c/1282c19:dd:d9:dd:c25:c25:d915:e64c
782c19:dd:d9:dd:c25:c25:d915:e64d/1282c19:dd:d9:dd:c25:c25:d915:e64d
792c19:dd:d9:dd:c25:c25:d915:e64e/1282c19:dd:d9:dd:c25:c25:d915:e64e
802c19:dd:d9:dd:c25:c25:d915:e64f/1282c19:dd:d9:dd:c25:c25:d915:e64f
812c19:dd:d9:dd:c25:c25:d915:e650/1282c19:dd:d9:dd:c25:c25:d915:e650
822c19:dd:d9:dd:c25:c25:d915:e651/1282c19:dd:d9:dd:c25:c25:d915:e651
832c19:dd:d9:dd:c25:c25:d915:e652/1282c19:dd:d9:dd:c25:c25:d915:e652
842c19:dd:d9:dd:c25:c25:d915:e653/1282c19:dd:d9:dd:c25:c25:d915:e653
852c19:dd:d9:dd:c25:c25:d915:e654/1282c19:dd:d9:dd:c25:c25:d915:e654
862c19:dd:d9:dd:c25:c25:d915:e655/1282c19:dd:d9:dd:c25:c25:d915:e655
872c19:dd:d9:dd:c25:c25:d915:e656/1282c19:dd:d9:dd:c25:c25:d915:e656
882c19:dd:d9:dd:c25:c25:d915:e657/1282c19:dd:d9:dd:c25:c25:d915:e657
892c19:dd:d9:dd:c25:c25:d915:e658/1282c19:dd:d9:dd:c25:c25:d915:e658
902c19:dd:d9:dd:c25:c25:d915:e659/1282c19:dd:d9:dd:c25:c25:d915:e659
912c19:dd:d9:dd:c25:c25:d915:e65a/1282c19:dd:d9:dd:c25:c25:d915:e65a
922c19:dd:d9:dd:c25:c25:d915:e65b/1282c19:dd:d9:dd:c25:c25:d915:e65b
932c19:dd:d9:dd:c25:c25:d915:e65c/1282c19:dd:d9:dd:c25:c25:d915:e65c
942c19:dd:d9:dd:c25:c25:d915:e65d/1282c19:dd:d9:dd:c25:c25:d915:e65d
952c19:dd:d9:dd:c25:c25:d915:e65e/1282c19:dd:d9:dd:c25:c25:d915:e65e
962c19:dd:d9:dd:c25:c25:d915:e65f/1282c19:dd:d9:dd:c25:c25:d915:e65f
972c19:dd:d9:dd:c25:c25:d915:e660/1282c19:dd:d9:dd:c25:c25:d915:e660
982c19:dd:d9:dd:c25:c25:d915:e661/1282c19:dd:d9:dd:c25:c25:d915:e661
992c19:dd:d9:dd:c25:c25:d915:e662/1282c19:dd:d9:dd:c25:c25:d915:e662
1002c19:dd:d9:dd:c25:c25:d915:e663/1282c19:dd:d9:dd:c25:c25:d915:e663
1012c19:dd:d9:dd:c25:c25:d915:e664/1282c19:dd:d9:dd:c25:c25:d915:e664
1022c19:dd:d9:dd:c25:c25:d915:e665/1282c19:dd:d9:dd:c25:c25:d915:e665
1032c19:dd:d9:dd:c25:c25:d915:e666/1282c19:dd:d9:dd:c25:c25:d915:e666
1042c19:dd:d9:dd:c25:c25:d915:e667/1282c19:dd:d9:dd:c25:c25:d915:e667
1052c19:dd:d9:dd:c25:c25:d915:e668/1282c19:dd:d9:dd:c25:c25:d915:e668
1062c19:dd:d9:dd:c25:c25:d915:e669/1282c19:dd:d9:dd:c25:c25:d915:e669
1072c19:dd:d9:dd:c25:c25:d915:e66a/1282c19:dd:d9:dd:c25:c25:d915:e66a
1082c19:dd:d9:dd:c25:c25:d915:e66b/1282c19:dd:d9:dd:c25:c25:d915:e66b
1092c19:dd:d9:dd:c25:c25:d915:e66c/1282c19:dd:d9:dd:c25:c25:d915:e66c
1102c19:dd:d9:dd:c25:c25:d915:e66d/1282c19:dd:d9:dd:c25:c25:d915:e66d
1112c19:dd:d9:dd:c25:c25:d915:e66e/1282c19:dd:d9:dd:c25:c25:d915:e66e
1122c19:dd:d9:dd:c25:c25:d915:e66f/1282c19:dd:d9:dd:c25:c25:d915:e66f
1132c19:dd:d9:dd:c25:c25:d915:e670/1282c19:dd:d9:dd:c25:c25:d915:e670
1142c19:dd:d9:dd:c25:c25:d915:e671/1282c19:dd:d9:dd:c25:c25:d915:e671
1152c19:dd:d9:dd:c25:c25:d915:e672/1282c19:dd:d9:dd:c25:c25:d915:e672
1162c19:dd:d9:dd:c25:c25:d915:e673/1282c19:dd:d9:dd:c25:c25:d915:e673
1172c19:dd:d9:dd:c25:c25:d915:e674/1282c19:dd:d9:dd:c25:c25:d915:e674
1182c19:dd:d9:dd:c25:c25:d915:e675/1282c19:dd:d9:dd:c25:c25:d915:e675
1192c19:dd:d9:dd:c25:c25:d915:e676/1282c19:dd:d9:dd:c25:c25:d915:e676
1202c19:dd:d9:dd:c25:c25:d915:e677/1282c19:dd:d9:dd:c25:c25:d915:e677
1212c19:dd:d9:dd:c25:c25:d915:e678/1282c19:dd:d9:dd:c25:c25:d915:e678
1222c19:dd:d9:dd:c25:c25:d915:e679/1282c19:dd:d9:dd:c25:c25:d915:e679
1232c19:dd:d9:dd:c25:c25:d915:e67a/1282c19:dd:d9:dd:c25:c25:d915:e67a
1242c19:dd:d9:dd:c25:c25:d915:e67b/1282c19:dd:d9:dd:c25:c25:d915:e67b
1252c19:dd:d9:dd:c25:c25:d915:e67c/1282c19:dd:d9:dd:c25:c25:d915:e67c
1262c19:dd:d9:dd:c25:c25:d915:e67d/1282c19:dd:d9:dd:c25:c25:d915:e67d
1272c19:dd:d9:dd:c25:c25:d915:e67e/1282c19:dd:d9:dd:c25:c25:d915:e67e
1282c19:dd:d9:dd:c25:c25:d915:e67f/1282c19:dd:d9:dd:c25:c25:d915:e67f
1292c19:dd:d9:dd:c25:c25:d915:e680/1282c19:dd:d9:dd:c25:c25:d915:e680
1302c19:dd:d9:dd:c25:c25:d915:e681/1282c19:dd:d9:dd:c25:c25:d915:e681
1312c19:dd:d9:dd:c25:c25:d915:e682/1282c19:dd:d9:dd:c25:c25:d915:e682
1322c19:dd:d9:dd:c25:c25:d915:e683/1282c19:dd:d9:dd:c25:c25:d915:e683
1332c19:dd:d9:dd:c25:c25:d915:e684/1282c19:dd:d9:dd:c25:c25:d915:e684
1342c19:dd:d9:dd:c25:c25:d915:e685/1282c19:dd:d9:dd:c25:c25:d915:e685
1352c19:dd:d9:dd:c25:c25:d915:e686/1282c19:dd:d9:dd:c25:c25:d915:e686
1362c19:dd:d9:dd:c25:c25:d915:e687/1282c19:dd:d9:dd:c25:c25:d915:e687
1372c19:dd:d9:dd:c25:c25:d915:e688/1282c19:dd:d9:dd:c25:c25:d915:e688
1382c19:dd:d9:dd:c25:c25:d915:e689/1282c19:dd:d9:dd:c25:c25:d915:e689
1392c19:dd:d9:dd:c25:c25:d915:e68a/1282c19:dd:d9:dd:c25:c25:d915:e68a
1402c19:dd:d9:dd:c25:c25:d915:e68b/1282c19:dd:d9:dd:c25:c25:d915:e68b
1412c19:dd:d9:dd:c25:c25:d915:e68c/1282c19:dd:d9:dd:c25:c25:d915:e68c
1422c19:dd:d9:dd:c25:c25:d915:e68d/1282c19:dd:d9:dd:c25:c25:d915:e68d
1432c19:dd:d9:dd:c25:c25:d915:e68e/1282c19:dd:d9:dd:c25:c25:d915:e68e
1442c19:dd:d9:dd:c25:c25:d915:e68f/1282c19:dd:d9:dd:c25:c25:d915:e68f
1452c19:dd:d9:dd:c25:c25:d915:e690/1282c19:dd:d9:dd:c25:c25:d915:e690
1462c19:dd:d9:dd:c25:c25:d915:e691/1282c19:dd:d9:dd:c25:c25:d915:e691
1472c19:dd:d9:dd:c25:c25:d915:e692/1282c19:dd:d9:dd:c25:c25:d915:e692
1482c19:dd:d9:dd:c25:c25:d915:e693/1282c19:dd:d9:dd:c25:c25:d915:e693
1492c19:dd:d9:dd:c25:c25:d915:e694/1282c19:dd:d9:dd:c25:c25:d915:e694
1502c19:dd:d9:dd:c25:c25:d915:e695/1282c19:dd:d9:dd:c25:c25:d915:e695
1512c19:dd:d9:dd:c25:c25:d915:e696/1282c19:dd:d9:dd:c25:c25:d915:e696
1522c19:dd:d9:dd:c25:c25:d915:e697/1282c19:dd:d9:dd:c25:c25:d915:e697
1532c19:dd:d9:dd:c25:c25:d915:e698/1282c19:dd:d9:dd:c25:c25:d915:e698
1542c19:dd:d9:dd:c25:c25:d915:e699/1282c19:dd:d9:dd:c25:c25:d915:e699
1552c19:dd:d9:dd:c25:c25:d915:e69a/1282c19:dd:d9:dd:c25:c25:d915:e69a
1562c19:dd:d9:dd:c25:c25:d915:e69b/1282c19:dd:d9:dd:c25:c25:d915:e69b
1572c19:dd:d9:dd:c25:c25:d915:e69c/1282c19:dd:d9:dd:c25:c25:d915:e69c
1582c19:dd:d9:dd:c25:c25:d915:e69d/1282c19:dd:d9:dd:c25:c25:d915:e69d
1592c19:dd:d9:dd:c25:c25:d915:e69e/1282c19:dd:d9:dd:c25:c25:d915:e69e
1602c19:dd:d9:dd:c25:c25:d915:e69f/1282c19:dd:d9:dd:c25:c25:d915:e69f
1612c19:dd:d9:dd:c25:c25:d915:e6a0/1282c19:dd:d9:dd:c25:c25:d915:e6a0
1622c19:dd:d9:dd:c25:c25:d915:e6a1/1282c19:dd:d9:dd:c25:c25:d915:e6a1
1632c19:dd:d9:dd:c25:c25:d915:e6a2/1282c19:dd:d9:dd:c25:c25:d915:e6a2
1642c19:dd:d9:dd:c25:c25:d915:e6a3/1282c19:dd:d9:dd:c25:c25:d915:e6a3
1652c19:dd:d9:dd:c25:c25:d915:e6a4/1282c19:dd:d9:dd:c25:c25:d915:e6a4
1662c19:dd:d9:dd:c25:c25:d915:e6a5/1282c19:dd:d9:dd:c25:c25:d915:e6a5
1672c19:dd:d9:dd:c25:c25:d915:e6a6/1282c19:dd:d9:dd:c25:c25:d915:e6a6
1682c19:dd:d9:dd:c25:c25:d915:e6a7/1282c19:dd:d9:dd:c25:c25:d915:e6a7
1692c19:dd:d9:dd:c25:c25:d915:e6a8/1282c19:dd:d9:dd:c25:c25:d915:e6a8
1702c19:dd:d9:dd:c25:c25:d915:e6a9/1282c19:dd:d9:dd:c25:c25:d915:e6a9
1712c19:dd:d9:dd:c25:c25:d915:e6aa/1282c19:dd:d9:dd:c25:c25:d915:e6aa
1722c19:dd:d9:dd:c25:c25:d915:e6ab/1282c19:dd:d9:dd:c25:c25:d915:e6ab
1732c19:dd:d9:dd:c25:c25:d915:e6ac/1282c19:dd:d9:dd:c25:c25:d915:e6ac
1742c19:dd:d9:dd:c25:c25:d915:e6ad/1282c19:dd:d9:dd:c25:c25:d915:e6ad
1752c19:dd:d9:dd:c25:c25:d915:e6ae/1282c19:dd:d9:dd:c25:c25:d915:e6ae
1762c19:dd:d9:dd:c25:c25:d915:e6af/1282c19:dd:d9:dd:c25:c25:d915:e6af
1772c19:dd:d9:dd:c25:c25:d915:e6b0/1282c19:dd:d9:dd:c25:c25:d915:e6b0
1782c19:dd:d9:dd:c25:c25:d915:e6b1/1282c19:dd:d9:dd:c25:c25:d915:e6b1
1792c19:dd:d9:dd:c25:c25:d915:e6b2/1282c19:dd:d9:dd:c25:c25:d915:e6b2
1802c19:dd:d9:dd:c25:c25:d915:e6b3/1282c19:dd:d9:dd:c25:c25:d915:e6b3
1812c19:dd:d9:dd:c25:c25:d915:e6b4/1282c19:dd:d9:dd:c25:c25:d915:e6b4
1822c19:dd:d9:dd:c25:c25:d915:e6b5/1282c19:dd:d9:dd:c25:c25:d915:e6b5
1832c19:dd:d9:dd:c25:c25:d915:e6b6/1282c19:dd:d9:dd:c25:c25:d915:e6b6
1842c19:dd:d9:dd:c25:c25:d915:e6b7/1282c19:dd:d9:dd:c25:c25:d915:e6b7
1852c19:dd:d9:dd:c25:c25:d915:e6b8/1282c19:dd:d9:dd:c25:c25:d915:e6b8
1862c19:dd:d9:dd:c25:c25:d915:e6b9/1282c19:dd:d9:dd:c25:c25:d915:e6b9
1872c19:dd:d9:dd:c25:c25:d915:e6ba/1282c19:dd:d9:dd:c25:c25:d915:e6ba
1882c19:dd:d9:dd:c25:c25:d915:e6bb/1282c19:dd:d9:dd:c25:c25:d915:e6bb
1892c19:dd:d9:dd:c25:c25:d915:e6bc/1282c19:dd:d9:dd:c25:c25:d915:e6bc
1902c19:dd:d9:dd:c25:c25:d915:e6bd/1282c19:dd:d9:dd:c25:c25:d915:e6bd
1912c19:dd:d9:dd:c25:c25:d915:e6be/1282c19:dd:d9:dd:c25:c25:d915:e6be
1922c19:dd:d9:dd:c25:c25:d915:e6bf/1282c19:dd:d9:dd:c25:c25:d915:e6bf
1932c19:dd:d9:dd:c25:c25:d915:e6c0/1282c19:dd:d9:dd:c25:c25:d915:e6c0
1942c19:dd:d9:dd:c25:c25:d915:e6c1/1282c19:dd:d9:dd:c25:c25:d915:e6c1
1952c19:dd:d9:dd:c25:c25:d915:e6c2/1282c19:dd:d9:dd:c25:c25:d915:e6c2
1962c19:dd:d9:dd:c25:c25:d915:e6c3/1282c19:dd:d9:dd:c25:c25:d915:e6c3
1972c19:dd:d9:dd:c25:c25:d915:e6c4/1282c19:dd:d9:dd:c25:c25:d915:e6c4
1982c19:dd:d9:dd:c25:c25:d915:e6c5/1282c19:dd:d9:dd:c25:c25:d915:e6c5
1992c19:dd:d9:dd:c25:c25:d915:e6c6/1282c19:dd:d9:dd:c25:c25:d915:e6c6
2002c19:dd:d9:dd:c25:c25:d915:e6c7/1282c19:dd:d9:dd:c25:c25:d915:e6c7
2012c19:dd:d9:dd:c25:c25:d915:e6c8/1282c19:dd:d9:dd:c25:c25:d915:e6c8
2022c19:dd:d9:dd:c25:c25:d915:e6c9/1282c19:dd:d9:dd:c25:c25:d915:e6c9
2032c19:dd:d9:dd:c25:c25:d915:e6ca/1282c19:dd:d9:dd:c25:c25:d915:e6ca
2042c19:dd:d9:dd:c25:c25:d915:e6cb/1282c19:dd:d9:dd:c25:c25:d915:e6cb
2052c19:dd:d9:dd:c25:c25:d915:e6cc/1282c19:dd:d9:dd:c25:c25:d915:e6cc
2062c19:dd:d9:dd:c25:c25:d915:e6cd/1282c19:dd:d9:dd:c25:c25:d915:e6cd
2072c19:dd:d9:dd:c25:c25:d915:e6ce/1282c19:dd:d9:dd:c25:c25:d915:e6ce
2082c19:dd:d9:dd:c25:c25:d915:e6cf/1282c19:dd:d9:dd:c25:c25:d915:e6cf
2092c19:dd:d9:dd:c25:c25:d915:e6d0/1282c19:dd:d9:dd:c25:c25:d915:e6d0
2102c19:dd:d9:dd:c25:c25:d915:e6d1/1282c19:dd:d9:dd:c25:c25:d915:e6d1
2112c19:dd:d9:dd:c25:c25:d915:e6d2/1282c19:dd:d9:dd:c25:c25:d915:e6d2
2122c19:dd:d9:dd:c25:c25:d915:e6d3/1282c19:dd:d9:dd:c25:c25:d915:e6d3
2132c19:dd:d9:dd:c25:c25:d915:e6d4/1282c19:dd:d9:dd:c25:c25:d915:e6d4
2142c19:dd:d9:dd:c25:c25:d915:e6d5/1282c19:dd:d9:dd:c25:c25:d915:e6d5
2152c19:dd:d9:dd:c25:c25:d915:e6d6/1282c19:dd:d9:dd:c25:c25:d915:e6d6
2162c19:dd:d9:dd:c25:c25:d915:e6d7/1282c19:dd:d9:dd:c25:c25:d915:e6d7
2172c19:dd:d9:dd:c25:c25:d915:e6d8/1282c19:dd:d9:dd:c25:c25:d915:e6d8
2182c19:dd:d9:dd:c25:c25:d915:e6d9/1282c19:dd:d9:dd:c25:c25:d915:e6d9
2192c19:dd:d9:dd:c25:c25:d915:e6da/1282c19:dd:d9:dd:c25:c25:d915:e6da
2202c19:dd:d9:dd:c25:c25:d915:e6db/1282c19:dd:d9:dd:c25:c25:d915:e6db
2212c19:dd:d9:dd:c25:c25:d915:e6dc/1282c19:dd:d9:dd:c25:c25:d915:e6dc
2222c19:dd:d9:dd:c25:c25:d915:e6dd/1282c19:dd:d9:dd:c25:c25:d915:e6dd
2232c19:dd:d9:dd:c25:c25:d915:e6de/1282c19:dd:d9:dd:c25:c25:d915:e6de
2242c19:dd:d9:dd:c25:c25:d915:e6df/1282c19:dd:d9:dd:c25:c25:d915:e6df
2252c19:dd:d9:dd:c25:c25:d915:e6e0/1282c19:dd:d9:dd:c25:c25:d915:e6e0
2262c19:dd:d9:dd:c25:c25:d915:e6e1/1282c19:dd:d9:dd:c25:c25:d915:e6e1
2272c19:dd:d9:dd:c25:c25:d915:e6e2/1282c19:dd:d9:dd:c25:c25:d915:e6e2
2282c19:dd:d9:dd:c25:c25:d915:e6e3/1282c19:dd:d9:dd:c25:c25:d915:e6e3
2292c19:dd:d9:dd:c25:c25:d915:e6e4/1282c19:dd:d9:dd:c25:c25:d915:e6e4
2302c19:dd:d9:dd:c25:c25:d915:e6e5/1282c19:dd:d9:dd:c25:c25:d915:e6e5
2312c19:dd:d9:dd:c25:c25:d915:e6e6/1282c19:dd:d9:dd:c25:c25:d915:e6e6
2322c19:dd:d9:dd:c25:c25:d915:e6e7/1282c19:dd:d9:dd:c25:c25:d915:e6e7
2332c19:dd:d9:dd:c25:c25:d915:e6e8/1282c19:dd:d9:dd:c25:c25:d915:e6e8
2342c19:dd:d9:dd:c25:c25:d915:e6e9/1282c19:dd:d9:dd:c25:c25:d915:e6e9
2352c19:dd:d9:dd:c25:c25:d915:e6ea/1282c19:dd:d9:dd:c25:c25:d915:e6ea
2362c19:dd:d9:dd:c25:c25:d915:e6eb/1282c19:dd:d9:dd:c25:c25:d915:e6eb
2372c19:dd:d9:dd:c25:c25:d915:e6ec/1282c19:dd:d9:dd:c25:c25:d915:e6ec
2382c19:dd:d9:dd:c25:c25:d915:e6ed/1282c19:dd:d9:dd:c25:c25:d915:e6ed
2392c19:dd:d9:dd:c25:c25:d915:e6ee/1282c19:dd:d9:dd:c25:c25:d915:e6ee
2402c19:dd:d9:dd:c25:c25:d915:e6ef/1282c19:dd:d9:dd:c25:c25:d915:e6ef
2412c19:dd:d9:dd:c25:c25:d915:e6f0/1282c19:dd:d9:dd:c25:c25:d915:e6f0
2422c19:dd:d9:dd:c25:c25:d915:e6f1/1282c19:dd:d9:dd:c25:c25:d915:e6f1
2432c19:dd:d9:dd:c25:c25:d915:e6f2/1282c19:dd:d9:dd:c25:c25:d915:e6f2
2442c19:dd:d9:dd:c25:c25:d915:e6f3/1282c19:dd:d9:dd:c25:c25:d915:e6f3
2452c19:dd:d9:dd:c25:c25:d915:e6f4/1282c19:dd:d9:dd:c25:c25:d915:e6f4
2462c19:dd:d9:dd:c25:c25:d915:e6f5/1282c19:dd:d9:dd:c25:c25:d915:e6f5
2472c19:dd:d9:dd:c25:c25:d915:e6f6/1282c19:dd:d9:dd:c25:c25:d915:e6f6
2482c19:dd:d9:dd:c25:c25:d915:e6f7/1282c19:dd:d9:dd:c25:c25:d915:e6f7
2492c19:dd:d9:dd:c25:c25:d915:e6f8/1282c19:dd:d9:dd:c25:c25:d915:e6f8
2502c19:dd:d9:dd:c25:c25:d915:e6f9/1282c19:dd:d9:dd:c25:c25:d915:e6f9
2512c19:dd:d9:dd:c25:c25:d915:e6fa/1282c19:dd:d9:dd:c25:c25:d915:e6fa
2522c19:dd:d9:dd:c25:c25:d915:e6fb/1282c19:dd:d9:dd:c25:c25:d915:e6fb
2532c19:dd:d9:dd:c25:c25:d915:e6fc/1282c19:dd:d9:dd:c25:c25:d915:e6fc
2542c19:dd:d9:dd:c25:c25:d915:e6fd/1282c19:dd:d9:dd:c25:c25:d915:e6fd
2552c19:dd:d9:dd:c25:c25:d915:e6fe/1282c19:dd:d9:dd:c25:c25:d915:e6fe
2562c19:dd:d9:dd:c25:c25:d915:e6ff/1282c19:dd:d9:dd:c25:c25:d915:e6ff

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.