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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/116
Addresses4,096
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:c001:a000/116
First address
2c19:dd:d9:dd:c25:c25:c001:a000
Last address
2c19:dd:d9:dd:c25:c25:c001:afff
Addresses
4,096
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:c001:a000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
a.1.0.0.c.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/127
/117 (2)/118 (4)/119 (8)/120 (16)/124 (256)/127 (2,048)/128 (4,096)

2c19:dd:d9:dd:c25:c25:c001:a000/116 makes 2,048 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:c001:a000/1272c19:dd:d9:dd:c25:c25:c001:a001
22c19:dd:d9:dd:c25:c25:c001:a002/1272c19:dd:d9:dd:c25:c25:c001:a003
32c19:dd:d9:dd:c25:c25:c001:a004/1272c19:dd:d9:dd:c25:c25:c001:a005
42c19:dd:d9:dd:c25:c25:c001:a006/1272c19:dd:d9:dd:c25:c25:c001:a007
52c19:dd:d9:dd:c25:c25:c001:a008/1272c19:dd:d9:dd:c25:c25:c001:a009
62c19:dd:d9:dd:c25:c25:c001:a00a/1272c19:dd:d9:dd:c25:c25:c001:a00b
72c19:dd:d9:dd:c25:c25:c001:a00c/1272c19:dd:d9:dd:c25:c25:c001:a00d
82c19:dd:d9:dd:c25:c25:c001:a00e/1272c19:dd:d9:dd:c25:c25:c001:a00f
92c19:dd:d9:dd:c25:c25:c001:a010/1272c19:dd:d9:dd:c25:c25:c001:a011
102c19:dd:d9:dd:c25:c25:c001:a012/1272c19:dd:d9:dd:c25:c25:c001:a013
112c19:dd:d9:dd:c25:c25:c001:a014/1272c19:dd:d9:dd:c25:c25:c001:a015
122c19:dd:d9:dd:c25:c25:c001:a016/1272c19:dd:d9:dd:c25:c25:c001:a017
132c19:dd:d9:dd:c25:c25:c001:a018/1272c19:dd:d9:dd:c25:c25:c001:a019
142c19:dd:d9:dd:c25:c25:c001:a01a/1272c19:dd:d9:dd:c25:c25:c001:a01b
152c19:dd:d9:dd:c25:c25:c001:a01c/1272c19:dd:d9:dd:c25:c25:c001:a01d
162c19:dd:d9:dd:c25:c25:c001:a01e/1272c19:dd:d9:dd:c25:c25:c001:a01f
172c19:dd:d9:dd:c25:c25:c001:a020/1272c19:dd:d9:dd:c25:c25:c001:a021
182c19:dd:d9:dd:c25:c25:c001:a022/1272c19:dd:d9:dd:c25:c25:c001:a023
192c19:dd:d9:dd:c25:c25:c001:a024/1272c19:dd:d9:dd:c25:c25:c001:a025
202c19:dd:d9:dd:c25:c25:c001:a026/1272c19:dd:d9:dd:c25:c25:c001:a027
212c19:dd:d9:dd:c25:c25:c001:a028/1272c19:dd:d9:dd:c25:c25:c001:a029
222c19:dd:d9:dd:c25:c25:c001:a02a/1272c19:dd:d9:dd:c25:c25:c001:a02b
232c19:dd:d9:dd:c25:c25:c001:a02c/1272c19:dd:d9:dd:c25:c25:c001:a02d
242c19:dd:d9:dd:c25:c25:c001:a02e/1272c19:dd:d9:dd:c25:c25:c001:a02f
252c19:dd:d9:dd:c25:c25:c001:a030/1272c19:dd:d9:dd:c25:c25:c001:a031
262c19:dd:d9:dd:c25:c25:c001:a032/1272c19:dd:d9:dd:c25:c25:c001:a033
272c19:dd:d9:dd:c25:c25:c001:a034/1272c19:dd:d9:dd:c25:c25:c001:a035
282c19:dd:d9:dd:c25:c25:c001:a036/1272c19:dd:d9:dd:c25:c25:c001:a037
292c19:dd:d9:dd:c25:c25:c001:a038/1272c19:dd:d9:dd:c25:c25:c001:a039
302c19:dd:d9:dd:c25:c25:c001:a03a/1272c19:dd:d9:dd:c25:c25:c001:a03b
312c19:dd:d9:dd:c25:c25:c001:a03c/1272c19:dd:d9:dd:c25:c25:c001:a03d
322c19:dd:d9:dd:c25:c25:c001:a03e/1272c19:dd:d9:dd:c25:c25:c001:a03f
332c19:dd:d9:dd:c25:c25:c001:a040/1272c19:dd:d9:dd:c25:c25:c001:a041
342c19:dd:d9:dd:c25:c25:c001:a042/1272c19:dd:d9:dd:c25:c25:c001:a043
352c19:dd:d9:dd:c25:c25:c001:a044/1272c19:dd:d9:dd:c25:c25:c001:a045
362c19:dd:d9:dd:c25:c25:c001:a046/1272c19:dd:d9:dd:c25:c25:c001:a047
372c19:dd:d9:dd:c25:c25:c001:a048/1272c19:dd:d9:dd:c25:c25:c001:a049
382c19:dd:d9:dd:c25:c25:c001:a04a/1272c19:dd:d9:dd:c25:c25:c001:a04b
392c19:dd:d9:dd:c25:c25:c001:a04c/1272c19:dd:d9:dd:c25:c25:c001:a04d
402c19:dd:d9:dd:c25:c25:c001:a04e/1272c19:dd:d9:dd:c25:c25:c001:a04f
412c19:dd:d9:dd:c25:c25:c001:a050/1272c19:dd:d9:dd:c25:c25:c001:a051
422c19:dd:d9:dd:c25:c25:c001:a052/1272c19:dd:d9:dd:c25:c25:c001:a053
432c19:dd:d9:dd:c25:c25:c001:a054/1272c19:dd:d9:dd:c25:c25:c001:a055
442c19:dd:d9:dd:c25:c25:c001:a056/1272c19:dd:d9:dd:c25:c25:c001:a057
452c19:dd:d9:dd:c25:c25:c001:a058/1272c19:dd:d9:dd:c25:c25:c001:a059
462c19:dd:d9:dd:c25:c25:c001:a05a/1272c19:dd:d9:dd:c25:c25:c001:a05b
472c19:dd:d9:dd:c25:c25:c001:a05c/1272c19:dd:d9:dd:c25:c25:c001:a05d
482c19:dd:d9:dd:c25:c25:c001:a05e/1272c19:dd:d9:dd:c25:c25:c001:a05f
492c19:dd:d9:dd:c25:c25:c001:a060/1272c19:dd:d9:dd:c25:c25:c001:a061
502c19:dd:d9:dd:c25:c25:c001:a062/1272c19:dd:d9:dd:c25:c25:c001:a063
512c19:dd:d9:dd:c25:c25:c001:a064/1272c19:dd:d9:dd:c25:c25:c001:a065
522c19:dd:d9:dd:c25:c25:c001:a066/1272c19:dd:d9:dd:c25:c25:c001:a067
532c19:dd:d9:dd:c25:c25:c001:a068/1272c19:dd:d9:dd:c25:c25:c001:a069
542c19:dd:d9:dd:c25:c25:c001:a06a/1272c19:dd:d9:dd:c25:c25:c001:a06b
552c19:dd:d9:dd:c25:c25:c001:a06c/1272c19:dd:d9:dd:c25:c25:c001:a06d
562c19:dd:d9:dd:c25:c25:c001:a06e/1272c19:dd:d9:dd:c25:c25:c001:a06f
572c19:dd:d9:dd:c25:c25:c001:a070/1272c19:dd:d9:dd:c25:c25:c001:a071
582c19:dd:d9:dd:c25:c25:c001:a072/1272c19:dd:d9:dd:c25:c25:c001:a073
592c19:dd:d9:dd:c25:c25:c001:a074/1272c19:dd:d9:dd:c25:c25:c001:a075
602c19:dd:d9:dd:c25:c25:c001:a076/1272c19:dd:d9:dd:c25:c25:c001:a077
612c19:dd:d9:dd:c25:c25:c001:a078/1272c19:dd:d9:dd:c25:c25:c001:a079
622c19:dd:d9:dd:c25:c25:c001:a07a/1272c19:dd:d9:dd:c25:c25:c001:a07b
632c19:dd:d9:dd:c25:c25:c001:a07c/1272c19:dd:d9:dd:c25:c25:c001:a07d
642c19:dd:d9:dd:c25:c25:c001:a07e/1272c19:dd:d9:dd:c25:c25:c001:a07f
652c19:dd:d9:dd:c25:c25:c001:a080/1272c19:dd:d9:dd:c25:c25:c001:a081
662c19:dd:d9:dd:c25:c25:c001:a082/1272c19:dd:d9:dd:c25:c25:c001:a083
672c19:dd:d9:dd:c25:c25:c001:a084/1272c19:dd:d9:dd:c25:c25:c001:a085
682c19:dd:d9:dd:c25:c25:c001:a086/1272c19:dd:d9:dd:c25:c25:c001:a087
692c19:dd:d9:dd:c25:c25:c001:a088/1272c19:dd:d9:dd:c25:c25:c001:a089
702c19:dd:d9:dd:c25:c25:c001:a08a/1272c19:dd:d9:dd:c25:c25:c001:a08b
712c19:dd:d9:dd:c25:c25:c001:a08c/1272c19:dd:d9:dd:c25:c25:c001:a08d
722c19:dd:d9:dd:c25:c25:c001:a08e/1272c19:dd:d9:dd:c25:c25:c001:a08f
732c19:dd:d9:dd:c25:c25:c001:a090/1272c19:dd:d9:dd:c25:c25:c001:a091
742c19:dd:d9:dd:c25:c25:c001:a092/1272c19:dd:d9:dd:c25:c25:c001:a093
752c19:dd:d9:dd:c25:c25:c001:a094/1272c19:dd:d9:dd:c25:c25:c001:a095
762c19:dd:d9:dd:c25:c25:c001:a096/1272c19:dd:d9:dd:c25:c25:c001:a097
772c19:dd:d9:dd:c25:c25:c001:a098/1272c19:dd:d9:dd:c25:c25:c001:a099
782c19:dd:d9:dd:c25:c25:c001:a09a/1272c19:dd:d9:dd:c25:c25:c001:a09b
792c19:dd:d9:dd:c25:c25:c001:a09c/1272c19:dd:d9:dd:c25:c25:c001:a09d
802c19:dd:d9:dd:c25:c25:c001:a09e/1272c19:dd:d9:dd:c25:c25:c001:a09f
812c19:dd:d9:dd:c25:c25:c001:a0a0/1272c19:dd:d9:dd:c25:c25:c001:a0a1
822c19:dd:d9:dd:c25:c25:c001:a0a2/1272c19:dd:d9:dd:c25:c25:c001:a0a3
832c19:dd:d9:dd:c25:c25:c001:a0a4/1272c19:dd:d9:dd:c25:c25:c001:a0a5
842c19:dd:d9:dd:c25:c25:c001:a0a6/1272c19:dd:d9:dd:c25:c25:c001:a0a7
852c19:dd:d9:dd:c25:c25:c001:a0a8/1272c19:dd:d9:dd:c25:c25:c001:a0a9
862c19:dd:d9:dd:c25:c25:c001:a0aa/1272c19:dd:d9:dd:c25:c25:c001:a0ab
872c19:dd:d9:dd:c25:c25:c001:a0ac/1272c19:dd:d9:dd:c25:c25:c001:a0ad
882c19:dd:d9:dd:c25:c25:c001:a0ae/1272c19:dd:d9:dd:c25:c25:c001:a0af
892c19:dd:d9:dd:c25:c25:c001:a0b0/1272c19:dd:d9:dd:c25:c25:c001:a0b1
902c19:dd:d9:dd:c25:c25:c001:a0b2/1272c19:dd:d9:dd:c25:c25:c001:a0b3
912c19:dd:d9:dd:c25:c25:c001:a0b4/1272c19:dd:d9:dd:c25:c25:c001:a0b5
922c19:dd:d9:dd:c25:c25:c001:a0b6/1272c19:dd:d9:dd:c25:c25:c001:a0b7
932c19:dd:d9:dd:c25:c25:c001:a0b8/1272c19:dd:d9:dd:c25:c25:c001:a0b9
942c19:dd:d9:dd:c25:c25:c001:a0ba/1272c19:dd:d9:dd:c25:c25:c001:a0bb
952c19:dd:d9:dd:c25:c25:c001:a0bc/1272c19:dd:d9:dd:c25:c25:c001:a0bd
962c19:dd:d9:dd:c25:c25:c001:a0be/1272c19:dd:d9:dd:c25:c25:c001:a0bf
972c19:dd:d9:dd:c25:c25:c001:a0c0/1272c19:dd:d9:dd:c25:c25:c001:a0c1
982c19:dd:d9:dd:c25:c25:c001:a0c2/1272c19:dd:d9:dd:c25:c25:c001:a0c3
992c19:dd:d9:dd:c25:c25:c001:a0c4/1272c19:dd:d9:dd:c25:c25:c001:a0c5
1002c19:dd:d9:dd:c25:c25:c001:a0c6/1272c19:dd:d9:dd:c25:c25:c001:a0c7
1012c19:dd:d9:dd:c25:c25:c001:a0c8/1272c19:dd:d9:dd:c25:c25:c001:a0c9
1022c19:dd:d9:dd:c25:c25:c001:a0ca/1272c19:dd:d9:dd:c25:c25:c001:a0cb
1032c19:dd:d9:dd:c25:c25:c001:a0cc/1272c19:dd:d9:dd:c25:c25:c001:a0cd
1042c19:dd:d9:dd:c25:c25:c001:a0ce/1272c19:dd:d9:dd:c25:c25:c001:a0cf
1052c19:dd:d9:dd:c25:c25:c001:a0d0/1272c19:dd:d9:dd:c25:c25:c001:a0d1
1062c19:dd:d9:dd:c25:c25:c001:a0d2/1272c19:dd:d9:dd:c25:c25:c001:a0d3
1072c19:dd:d9:dd:c25:c25:c001:a0d4/1272c19:dd:d9:dd:c25:c25:c001:a0d5
1082c19:dd:d9:dd:c25:c25:c001:a0d6/1272c19:dd:d9:dd:c25:c25:c001:a0d7
1092c19:dd:d9:dd:c25:c25:c001:a0d8/1272c19:dd:d9:dd:c25:c25:c001:a0d9
1102c19:dd:d9:dd:c25:c25:c001:a0da/1272c19:dd:d9:dd:c25:c25:c001:a0db
1112c19:dd:d9:dd:c25:c25:c001:a0dc/1272c19:dd:d9:dd:c25:c25:c001:a0dd
1122c19:dd:d9:dd:c25:c25:c001:a0de/1272c19:dd:d9:dd:c25:c25:c001:a0df
1132c19:dd:d9:dd:c25:c25:c001:a0e0/1272c19:dd:d9:dd:c25:c25:c001:a0e1
1142c19:dd:d9:dd:c25:c25:c001:a0e2/1272c19:dd:d9:dd:c25:c25:c001:a0e3
1152c19:dd:d9:dd:c25:c25:c001:a0e4/1272c19:dd:d9:dd:c25:c25:c001:a0e5
1162c19:dd:d9:dd:c25:c25:c001:a0e6/1272c19:dd:d9:dd:c25:c25:c001:a0e7
1172c19:dd:d9:dd:c25:c25:c001:a0e8/1272c19:dd:d9:dd:c25:c25:c001:a0e9
1182c19:dd:d9:dd:c25:c25:c001:a0ea/1272c19:dd:d9:dd:c25:c25:c001:a0eb
1192c19:dd:d9:dd:c25:c25:c001:a0ec/1272c19:dd:d9:dd:c25:c25:c001:a0ed
1202c19:dd:d9:dd:c25:c25:c001:a0ee/1272c19:dd:d9:dd:c25:c25:c001:a0ef
1212c19:dd:d9:dd:c25:c25:c001:a0f0/1272c19:dd:d9:dd:c25:c25:c001:a0f1
1222c19:dd:d9:dd:c25:c25:c001:a0f2/1272c19:dd:d9:dd:c25:c25:c001:a0f3
1232c19:dd:d9:dd:c25:c25:c001:a0f4/1272c19:dd:d9:dd:c25:c25:c001:a0f5
1242c19:dd:d9:dd:c25:c25:c001:a0f6/1272c19:dd:d9:dd:c25:c25:c001:a0f7
1252c19:dd:d9:dd:c25:c25:c001:a0f8/1272c19:dd:d9:dd:c25:c25:c001:a0f9
1262c19:dd:d9:dd:c25:c25:c001:a0fa/1272c19:dd:d9:dd:c25:c25:c001:a0fb
1272c19:dd:d9:dd:c25:c25:c001:a0fc/1272c19:dd:d9:dd:c25:c25:c001:a0fd
1282c19:dd:d9:dd:c25:c25:c001:a0fe/1272c19:dd:d9:dd:c25:c25:c001:a0ff
1292c19:dd:d9:dd:c25:c25:c001:a100/1272c19:dd:d9:dd:c25:c25:c001:a101
1302c19:dd:d9:dd:c25:c25:c001:a102/1272c19:dd:d9:dd:c25:c25:c001:a103
1312c19:dd:d9:dd:c25:c25:c001:a104/1272c19:dd:d9:dd:c25:c25:c001:a105
1322c19:dd:d9:dd:c25:c25:c001:a106/1272c19:dd:d9:dd:c25:c25:c001:a107
1332c19:dd:d9:dd:c25:c25:c001:a108/1272c19:dd:d9:dd:c25:c25:c001:a109
1342c19:dd:d9:dd:c25:c25:c001:a10a/1272c19:dd:d9:dd:c25:c25:c001:a10b
1352c19:dd:d9:dd:c25:c25:c001:a10c/1272c19:dd:d9:dd:c25:c25:c001:a10d
1362c19:dd:d9:dd:c25:c25:c001:a10e/1272c19:dd:d9:dd:c25:c25:c001:a10f
1372c19:dd:d9:dd:c25:c25:c001:a110/1272c19:dd:d9:dd:c25:c25:c001:a111
1382c19:dd:d9:dd:c25:c25:c001:a112/1272c19:dd:d9:dd:c25:c25:c001:a113
1392c19:dd:d9:dd:c25:c25:c001:a114/1272c19:dd:d9:dd:c25:c25:c001:a115
1402c19:dd:d9:dd:c25:c25:c001:a116/1272c19:dd:d9:dd:c25:c25:c001:a117
1412c19:dd:d9:dd:c25:c25:c001:a118/1272c19:dd:d9:dd:c25:c25:c001:a119
1422c19:dd:d9:dd:c25:c25:c001:a11a/1272c19:dd:d9:dd:c25:c25:c001:a11b
1432c19:dd:d9:dd:c25:c25:c001:a11c/1272c19:dd:d9:dd:c25:c25:c001:a11d
1442c19:dd:d9:dd:c25:c25:c001:a11e/1272c19:dd:d9:dd:c25:c25:c001:a11f
1452c19:dd:d9:dd:c25:c25:c001:a120/1272c19:dd:d9:dd:c25:c25:c001:a121
1462c19:dd:d9:dd:c25:c25:c001:a122/1272c19:dd:d9:dd:c25:c25:c001:a123
1472c19:dd:d9:dd:c25:c25:c001:a124/1272c19:dd:d9:dd:c25:c25:c001:a125
1482c19:dd:d9:dd:c25:c25:c001:a126/1272c19:dd:d9:dd:c25:c25:c001:a127
1492c19:dd:d9:dd:c25:c25:c001:a128/1272c19:dd:d9:dd:c25:c25:c001:a129
1502c19:dd:d9:dd:c25:c25:c001:a12a/1272c19:dd:d9:dd:c25:c25:c001:a12b
1512c19:dd:d9:dd:c25:c25:c001:a12c/1272c19:dd:d9:dd:c25:c25:c001:a12d
1522c19:dd:d9:dd:c25:c25:c001:a12e/1272c19:dd:d9:dd:c25:c25:c001:a12f
1532c19:dd:d9:dd:c25:c25:c001:a130/1272c19:dd:d9:dd:c25:c25:c001:a131
1542c19:dd:d9:dd:c25:c25:c001:a132/1272c19:dd:d9:dd:c25:c25:c001:a133
1552c19:dd:d9:dd:c25:c25:c001:a134/1272c19:dd:d9:dd:c25:c25:c001:a135
1562c19:dd:d9:dd:c25:c25:c001:a136/1272c19:dd:d9:dd:c25:c25:c001:a137
1572c19:dd:d9:dd:c25:c25:c001:a138/1272c19:dd:d9:dd:c25:c25:c001:a139
1582c19:dd:d9:dd:c25:c25:c001:a13a/1272c19:dd:d9:dd:c25:c25:c001:a13b
1592c19:dd:d9:dd:c25:c25:c001:a13c/1272c19:dd:d9:dd:c25:c25:c001:a13d
1602c19:dd:d9:dd:c25:c25:c001:a13e/1272c19:dd:d9:dd:c25:c25:c001:a13f
1612c19:dd:d9:dd:c25:c25:c001:a140/1272c19:dd:d9:dd:c25:c25:c001:a141
1622c19:dd:d9:dd:c25:c25:c001:a142/1272c19:dd:d9:dd:c25:c25:c001:a143
1632c19:dd:d9:dd:c25:c25:c001:a144/1272c19:dd:d9:dd:c25:c25:c001:a145
1642c19:dd:d9:dd:c25:c25:c001:a146/1272c19:dd:d9:dd:c25:c25:c001:a147
1652c19:dd:d9:dd:c25:c25:c001:a148/1272c19:dd:d9:dd:c25:c25:c001:a149
1662c19:dd:d9:dd:c25:c25:c001:a14a/1272c19:dd:d9:dd:c25:c25:c001:a14b
1672c19:dd:d9:dd:c25:c25:c001:a14c/1272c19:dd:d9:dd:c25:c25:c001:a14d
1682c19:dd:d9:dd:c25:c25:c001:a14e/1272c19:dd:d9:dd:c25:c25:c001:a14f
1692c19:dd:d9:dd:c25:c25:c001:a150/1272c19:dd:d9:dd:c25:c25:c001:a151
1702c19:dd:d9:dd:c25:c25:c001:a152/1272c19:dd:d9:dd:c25:c25:c001:a153
1712c19:dd:d9:dd:c25:c25:c001:a154/1272c19:dd:d9:dd:c25:c25:c001:a155
1722c19:dd:d9:dd:c25:c25:c001:a156/1272c19:dd:d9:dd:c25:c25:c001:a157
1732c19:dd:d9:dd:c25:c25:c001:a158/1272c19:dd:d9:dd:c25:c25:c001:a159
1742c19:dd:d9:dd:c25:c25:c001:a15a/1272c19:dd:d9:dd:c25:c25:c001:a15b
1752c19:dd:d9:dd:c25:c25:c001:a15c/1272c19:dd:d9:dd:c25:c25:c001:a15d
1762c19:dd:d9:dd:c25:c25:c001:a15e/1272c19:dd:d9:dd:c25:c25:c001:a15f
1772c19:dd:d9:dd:c25:c25:c001:a160/1272c19:dd:d9:dd:c25:c25:c001:a161
1782c19:dd:d9:dd:c25:c25:c001:a162/1272c19:dd:d9:dd:c25:c25:c001:a163
1792c19:dd:d9:dd:c25:c25:c001:a164/1272c19:dd:d9:dd:c25:c25:c001:a165
1802c19:dd:d9:dd:c25:c25:c001:a166/1272c19:dd:d9:dd:c25:c25:c001:a167
1812c19:dd:d9:dd:c25:c25:c001:a168/1272c19:dd:d9:dd:c25:c25:c001:a169
1822c19:dd:d9:dd:c25:c25:c001:a16a/1272c19:dd:d9:dd:c25:c25:c001:a16b
1832c19:dd:d9:dd:c25:c25:c001:a16c/1272c19:dd:d9:dd:c25:c25:c001:a16d
1842c19:dd:d9:dd:c25:c25:c001:a16e/1272c19:dd:d9:dd:c25:c25:c001:a16f
1852c19:dd:d9:dd:c25:c25:c001:a170/1272c19:dd:d9:dd:c25:c25:c001:a171
1862c19:dd:d9:dd:c25:c25:c001:a172/1272c19:dd:d9:dd:c25:c25:c001:a173
1872c19:dd:d9:dd:c25:c25:c001:a174/1272c19:dd:d9:dd:c25:c25:c001:a175
1882c19:dd:d9:dd:c25:c25:c001:a176/1272c19:dd:d9:dd:c25:c25:c001:a177
1892c19:dd:d9:dd:c25:c25:c001:a178/1272c19:dd:d9:dd:c25:c25:c001:a179
1902c19:dd:d9:dd:c25:c25:c001:a17a/1272c19:dd:d9:dd:c25:c25:c001:a17b
1912c19:dd:d9:dd:c25:c25:c001:a17c/1272c19:dd:d9:dd:c25:c25:c001:a17d
1922c19:dd:d9:dd:c25:c25:c001:a17e/1272c19:dd:d9:dd:c25:c25:c001:a17f
1932c19:dd:d9:dd:c25:c25:c001:a180/1272c19:dd:d9:dd:c25:c25:c001:a181
1942c19:dd:d9:dd:c25:c25:c001:a182/1272c19:dd:d9:dd:c25:c25:c001:a183
1952c19:dd:d9:dd:c25:c25:c001:a184/1272c19:dd:d9:dd:c25:c25:c001:a185
1962c19:dd:d9:dd:c25:c25:c001:a186/1272c19:dd:d9:dd:c25:c25:c001:a187
1972c19:dd:d9:dd:c25:c25:c001:a188/1272c19:dd:d9:dd:c25:c25:c001:a189
1982c19:dd:d9:dd:c25:c25:c001:a18a/1272c19:dd:d9:dd:c25:c25:c001:a18b
1992c19:dd:d9:dd:c25:c25:c001:a18c/1272c19:dd:d9:dd:c25:c25:c001:a18d
2002c19:dd:d9:dd:c25:c25:c001:a18e/1272c19:dd:d9:dd:c25:c25:c001:a18f
2012c19:dd:d9:dd:c25:c25:c001:a190/1272c19:dd:d9:dd:c25:c25:c001:a191
2022c19:dd:d9:dd:c25:c25:c001:a192/1272c19:dd:d9:dd:c25:c25:c001:a193
2032c19:dd:d9:dd:c25:c25:c001:a194/1272c19:dd:d9:dd:c25:c25:c001:a195
2042c19:dd:d9:dd:c25:c25:c001:a196/1272c19:dd:d9:dd:c25:c25:c001:a197
2052c19:dd:d9:dd:c25:c25:c001:a198/1272c19:dd:d9:dd:c25:c25:c001:a199
2062c19:dd:d9:dd:c25:c25:c001:a19a/1272c19:dd:d9:dd:c25:c25:c001:a19b
2072c19:dd:d9:dd:c25:c25:c001:a19c/1272c19:dd:d9:dd:c25:c25:c001:a19d
2082c19:dd:d9:dd:c25:c25:c001:a19e/1272c19:dd:d9:dd:c25:c25:c001:a19f
2092c19:dd:d9:dd:c25:c25:c001:a1a0/1272c19:dd:d9:dd:c25:c25:c001:a1a1
2102c19:dd:d9:dd:c25:c25:c001:a1a2/1272c19:dd:d9:dd:c25:c25:c001:a1a3
2112c19:dd:d9:dd:c25:c25:c001:a1a4/1272c19:dd:d9:dd:c25:c25:c001:a1a5
2122c19:dd:d9:dd:c25:c25:c001:a1a6/1272c19:dd:d9:dd:c25:c25:c001:a1a7
2132c19:dd:d9:dd:c25:c25:c001:a1a8/1272c19:dd:d9:dd:c25:c25:c001:a1a9
2142c19:dd:d9:dd:c25:c25:c001:a1aa/1272c19:dd:d9:dd:c25:c25:c001:a1ab
2152c19:dd:d9:dd:c25:c25:c001:a1ac/1272c19:dd:d9:dd:c25:c25:c001:a1ad
2162c19:dd:d9:dd:c25:c25:c001:a1ae/1272c19:dd:d9:dd:c25:c25:c001:a1af
2172c19:dd:d9:dd:c25:c25:c001:a1b0/1272c19:dd:d9:dd:c25:c25:c001:a1b1
2182c19:dd:d9:dd:c25:c25:c001:a1b2/1272c19:dd:d9:dd:c25:c25:c001:a1b3
2192c19:dd:d9:dd:c25:c25:c001:a1b4/1272c19:dd:d9:dd:c25:c25:c001:a1b5
2202c19:dd:d9:dd:c25:c25:c001:a1b6/1272c19:dd:d9:dd:c25:c25:c001:a1b7
2212c19:dd:d9:dd:c25:c25:c001:a1b8/1272c19:dd:d9:dd:c25:c25:c001:a1b9
2222c19:dd:d9:dd:c25:c25:c001:a1ba/1272c19:dd:d9:dd:c25:c25:c001:a1bb
2232c19:dd:d9:dd:c25:c25:c001:a1bc/1272c19:dd:d9:dd:c25:c25:c001:a1bd
2242c19:dd:d9:dd:c25:c25:c001:a1be/1272c19:dd:d9:dd:c25:c25:c001:a1bf
2252c19:dd:d9:dd:c25:c25:c001:a1c0/1272c19:dd:d9:dd:c25:c25:c001:a1c1
2262c19:dd:d9:dd:c25:c25:c001:a1c2/1272c19:dd:d9:dd:c25:c25:c001:a1c3
2272c19:dd:d9:dd:c25:c25:c001:a1c4/1272c19:dd:d9:dd:c25:c25:c001:a1c5
2282c19:dd:d9:dd:c25:c25:c001:a1c6/1272c19:dd:d9:dd:c25:c25:c001:a1c7
2292c19:dd:d9:dd:c25:c25:c001:a1c8/1272c19:dd:d9:dd:c25:c25:c001:a1c9
2302c19:dd:d9:dd:c25:c25:c001:a1ca/1272c19:dd:d9:dd:c25:c25:c001:a1cb
2312c19:dd:d9:dd:c25:c25:c001:a1cc/1272c19:dd:d9:dd:c25:c25:c001:a1cd
2322c19:dd:d9:dd:c25:c25:c001:a1ce/1272c19:dd:d9:dd:c25:c25:c001:a1cf
2332c19:dd:d9:dd:c25:c25:c001:a1d0/1272c19:dd:d9:dd:c25:c25:c001:a1d1
2342c19:dd:d9:dd:c25:c25:c001:a1d2/1272c19:dd:d9:dd:c25:c25:c001:a1d3
2352c19:dd:d9:dd:c25:c25:c001:a1d4/1272c19:dd:d9:dd:c25:c25:c001:a1d5
2362c19:dd:d9:dd:c25:c25:c001:a1d6/1272c19:dd:d9:dd:c25:c25:c001:a1d7
2372c19:dd:d9:dd:c25:c25:c001:a1d8/1272c19:dd:d9:dd:c25:c25:c001:a1d9
2382c19:dd:d9:dd:c25:c25:c001:a1da/1272c19:dd:d9:dd:c25:c25:c001:a1db
2392c19:dd:d9:dd:c25:c25:c001:a1dc/1272c19:dd:d9:dd:c25:c25:c001:a1dd
2402c19:dd:d9:dd:c25:c25:c001:a1de/1272c19:dd:d9:dd:c25:c25:c001:a1df
2412c19:dd:d9:dd:c25:c25:c001:a1e0/1272c19:dd:d9:dd:c25:c25:c001:a1e1
2422c19:dd:d9:dd:c25:c25:c001:a1e2/1272c19:dd:d9:dd:c25:c25:c001:a1e3
2432c19:dd:d9:dd:c25:c25:c001:a1e4/1272c19:dd:d9:dd:c25:c25:c001:a1e5
2442c19:dd:d9:dd:c25:c25:c001:a1e6/1272c19:dd:d9:dd:c25:c25:c001:a1e7
2452c19:dd:d9:dd:c25:c25:c001:a1e8/1272c19:dd:d9:dd:c25:c25:c001:a1e9
2462c19:dd:d9:dd:c25:c25:c001:a1ea/1272c19:dd:d9:dd:c25:c25:c001:a1eb
2472c19:dd:d9:dd:c25:c25:c001:a1ec/1272c19:dd:d9:dd:c25:c25:c001:a1ed
2482c19:dd:d9:dd:c25:c25:c001:a1ee/1272c19:dd:d9:dd:c25:c25:c001:a1ef
2492c19:dd:d9:dd:c25:c25:c001:a1f0/1272c19:dd:d9:dd:c25:c25:c001:a1f1
2502c19:dd:d9:dd:c25:c25:c001:a1f2/1272c19:dd:d9:dd:c25:c25:c001:a1f3
2512c19:dd:d9:dd:c25:c25:c001:a1f4/1272c19:dd:d9:dd:c25:c25:c001:a1f5
2522c19:dd:d9:dd:c25:c25:c001:a1f6/1272c19:dd:d9:dd:c25:c25:c001:a1f7
2532c19:dd:d9:dd:c25:c25:c001:a1f8/1272c19:dd:d9:dd:c25:c25:c001:a1f9
2542c19:dd:d9:dd:c25:c25:c001:a1fa/1272c19:dd:d9:dd:c25:c25:c001:a1fb
2552c19:dd:d9:dd:c25:c25:c001:a1fc/1272c19:dd:d9:dd:c25:c25:c001:a1fd
2562c19:dd:d9:dd:c25:c25:c001:a1fe/1272c19:dd:d9:dd:c25:c25:c001:a1ff

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.