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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:d00b:e000/116
First address
2c19:dd:d9:dd:c25:c25:d00b:e000
Last address
2c19:dd:d9:dd:c25:c25:d00b:efff
Addresses
4,096
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d00b:e000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
e.b.0.0.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/127
/117 (2)/118 (4)/119 (8)/120 (16)/124 (256)/127 (2,048)/128 (4,096)

2c19:dd:d9:dd:c25:c25:d00b:e000/116 makes 2,048 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d00b:e000/1272c19:dd:d9:dd:c25:c25:d00b:e001
22c19:dd:d9:dd:c25:c25:d00b:e002/1272c19:dd:d9:dd:c25:c25:d00b:e003
32c19:dd:d9:dd:c25:c25:d00b:e004/1272c19:dd:d9:dd:c25:c25:d00b:e005
42c19:dd:d9:dd:c25:c25:d00b:e006/1272c19:dd:d9:dd:c25:c25:d00b:e007
52c19:dd:d9:dd:c25:c25:d00b:e008/1272c19:dd:d9:dd:c25:c25:d00b:e009
62c19:dd:d9:dd:c25:c25:d00b:e00a/1272c19:dd:d9:dd:c25:c25:d00b:e00b
72c19:dd:d9:dd:c25:c25:d00b:e00c/1272c19:dd:d9:dd:c25:c25:d00b:e00d
82c19:dd:d9:dd:c25:c25:d00b:e00e/1272c19:dd:d9:dd:c25:c25:d00b:e00f
92c19:dd:d9:dd:c25:c25:d00b:e010/1272c19:dd:d9:dd:c25:c25:d00b:e011
102c19:dd:d9:dd:c25:c25:d00b:e012/1272c19:dd:d9:dd:c25:c25:d00b:e013
112c19:dd:d9:dd:c25:c25:d00b:e014/1272c19:dd:d9:dd:c25:c25:d00b:e015
122c19:dd:d9:dd:c25:c25:d00b:e016/1272c19:dd:d9:dd:c25:c25:d00b:e017
132c19:dd:d9:dd:c25:c25:d00b:e018/1272c19:dd:d9:dd:c25:c25:d00b:e019
142c19:dd:d9:dd:c25:c25:d00b:e01a/1272c19:dd:d9:dd:c25:c25:d00b:e01b
152c19:dd:d9:dd:c25:c25:d00b:e01c/1272c19:dd:d9:dd:c25:c25:d00b:e01d
162c19:dd:d9:dd:c25:c25:d00b:e01e/1272c19:dd:d9:dd:c25:c25:d00b:e01f
172c19:dd:d9:dd:c25:c25:d00b:e020/1272c19:dd:d9:dd:c25:c25:d00b:e021
182c19:dd:d9:dd:c25:c25:d00b:e022/1272c19:dd:d9:dd:c25:c25:d00b:e023
192c19:dd:d9:dd:c25:c25:d00b:e024/1272c19:dd:d9:dd:c25:c25:d00b:e025
202c19:dd:d9:dd:c25:c25:d00b:e026/1272c19:dd:d9:dd:c25:c25:d00b:e027
212c19:dd:d9:dd:c25:c25:d00b:e028/1272c19:dd:d9:dd:c25:c25:d00b:e029
222c19:dd:d9:dd:c25:c25:d00b:e02a/1272c19:dd:d9:dd:c25:c25:d00b:e02b
232c19:dd:d9:dd:c25:c25:d00b:e02c/1272c19:dd:d9:dd:c25:c25:d00b:e02d
242c19:dd:d9:dd:c25:c25:d00b:e02e/1272c19:dd:d9:dd:c25:c25:d00b:e02f
252c19:dd:d9:dd:c25:c25:d00b:e030/1272c19:dd:d9:dd:c25:c25:d00b:e031
262c19:dd:d9:dd:c25:c25:d00b:e032/1272c19:dd:d9:dd:c25:c25:d00b:e033
272c19:dd:d9:dd:c25:c25:d00b:e034/1272c19:dd:d9:dd:c25:c25:d00b:e035
282c19:dd:d9:dd:c25:c25:d00b:e036/1272c19:dd:d9:dd:c25:c25:d00b:e037
292c19:dd:d9:dd:c25:c25:d00b:e038/1272c19:dd:d9:dd:c25:c25:d00b:e039
302c19:dd:d9:dd:c25:c25:d00b:e03a/1272c19:dd:d9:dd:c25:c25:d00b:e03b
312c19:dd:d9:dd:c25:c25:d00b:e03c/1272c19:dd:d9:dd:c25:c25:d00b:e03d
322c19:dd:d9:dd:c25:c25:d00b:e03e/1272c19:dd:d9:dd:c25:c25:d00b:e03f
332c19:dd:d9:dd:c25:c25:d00b:e040/1272c19:dd:d9:dd:c25:c25:d00b:e041
342c19:dd:d9:dd:c25:c25:d00b:e042/1272c19:dd:d9:dd:c25:c25:d00b:e043
352c19:dd:d9:dd:c25:c25:d00b:e044/1272c19:dd:d9:dd:c25:c25:d00b:e045
362c19:dd:d9:dd:c25:c25:d00b:e046/1272c19:dd:d9:dd:c25:c25:d00b:e047
372c19:dd:d9:dd:c25:c25:d00b:e048/1272c19:dd:d9:dd:c25:c25:d00b:e049
382c19:dd:d9:dd:c25:c25:d00b:e04a/1272c19:dd:d9:dd:c25:c25:d00b:e04b
392c19:dd:d9:dd:c25:c25:d00b:e04c/1272c19:dd:d9:dd:c25:c25:d00b:e04d
402c19:dd:d9:dd:c25:c25:d00b:e04e/1272c19:dd:d9:dd:c25:c25:d00b:e04f
412c19:dd:d9:dd:c25:c25:d00b:e050/1272c19:dd:d9:dd:c25:c25:d00b:e051
422c19:dd:d9:dd:c25:c25:d00b:e052/1272c19:dd:d9:dd:c25:c25:d00b:e053
432c19:dd:d9:dd:c25:c25:d00b:e054/1272c19:dd:d9:dd:c25:c25:d00b:e055
442c19:dd:d9:dd:c25:c25:d00b:e056/1272c19:dd:d9:dd:c25:c25:d00b:e057
452c19:dd:d9:dd:c25:c25:d00b:e058/1272c19:dd:d9:dd:c25:c25:d00b:e059
462c19:dd:d9:dd:c25:c25:d00b:e05a/1272c19:dd:d9:dd:c25:c25:d00b:e05b
472c19:dd:d9:dd:c25:c25:d00b:e05c/1272c19:dd:d9:dd:c25:c25:d00b:e05d
482c19:dd:d9:dd:c25:c25:d00b:e05e/1272c19:dd:d9:dd:c25:c25:d00b:e05f
492c19:dd:d9:dd:c25:c25:d00b:e060/1272c19:dd:d9:dd:c25:c25:d00b:e061
502c19:dd:d9:dd:c25:c25:d00b:e062/1272c19:dd:d9:dd:c25:c25:d00b:e063
512c19:dd:d9:dd:c25:c25:d00b:e064/1272c19:dd:d9:dd:c25:c25:d00b:e065
522c19:dd:d9:dd:c25:c25:d00b:e066/1272c19:dd:d9:dd:c25:c25:d00b:e067
532c19:dd:d9:dd:c25:c25:d00b:e068/1272c19:dd:d9:dd:c25:c25:d00b:e069
542c19:dd:d9:dd:c25:c25:d00b:e06a/1272c19:dd:d9:dd:c25:c25:d00b:e06b
552c19:dd:d9:dd:c25:c25:d00b:e06c/1272c19:dd:d9:dd:c25:c25:d00b:e06d
562c19:dd:d9:dd:c25:c25:d00b:e06e/1272c19:dd:d9:dd:c25:c25:d00b:e06f
572c19:dd:d9:dd:c25:c25:d00b:e070/1272c19:dd:d9:dd:c25:c25:d00b:e071
582c19:dd:d9:dd:c25:c25:d00b:e072/1272c19:dd:d9:dd:c25:c25:d00b:e073
592c19:dd:d9:dd:c25:c25:d00b:e074/1272c19:dd:d9:dd:c25:c25:d00b:e075
602c19:dd:d9:dd:c25:c25:d00b:e076/1272c19:dd:d9:dd:c25:c25:d00b:e077
612c19:dd:d9:dd:c25:c25:d00b:e078/1272c19:dd:d9:dd:c25:c25:d00b:e079
622c19:dd:d9:dd:c25:c25:d00b:e07a/1272c19:dd:d9:dd:c25:c25:d00b:e07b
632c19:dd:d9:dd:c25:c25:d00b:e07c/1272c19:dd:d9:dd:c25:c25:d00b:e07d
642c19:dd:d9:dd:c25:c25:d00b:e07e/1272c19:dd:d9:dd:c25:c25:d00b:e07f
652c19:dd:d9:dd:c25:c25:d00b:e080/1272c19:dd:d9:dd:c25:c25:d00b:e081
662c19:dd:d9:dd:c25:c25:d00b:e082/1272c19:dd:d9:dd:c25:c25:d00b:e083
672c19:dd:d9:dd:c25:c25:d00b:e084/1272c19:dd:d9:dd:c25:c25:d00b:e085
682c19:dd:d9:dd:c25:c25:d00b:e086/1272c19:dd:d9:dd:c25:c25:d00b:e087
692c19:dd:d9:dd:c25:c25:d00b:e088/1272c19:dd:d9:dd:c25:c25:d00b:e089
702c19:dd:d9:dd:c25:c25:d00b:e08a/1272c19:dd:d9:dd:c25:c25:d00b:e08b
712c19:dd:d9:dd:c25:c25:d00b:e08c/1272c19:dd:d9:dd:c25:c25:d00b:e08d
722c19:dd:d9:dd:c25:c25:d00b:e08e/1272c19:dd:d9:dd:c25:c25:d00b:e08f
732c19:dd:d9:dd:c25:c25:d00b:e090/1272c19:dd:d9:dd:c25:c25:d00b:e091
742c19:dd:d9:dd:c25:c25:d00b:e092/1272c19:dd:d9:dd:c25:c25:d00b:e093
752c19:dd:d9:dd:c25:c25:d00b:e094/1272c19:dd:d9:dd:c25:c25:d00b:e095
762c19:dd:d9:dd:c25:c25:d00b:e096/1272c19:dd:d9:dd:c25:c25:d00b:e097
772c19:dd:d9:dd:c25:c25:d00b:e098/1272c19:dd:d9:dd:c25:c25:d00b:e099
782c19:dd:d9:dd:c25:c25:d00b:e09a/1272c19:dd:d9:dd:c25:c25:d00b:e09b
792c19:dd:d9:dd:c25:c25:d00b:e09c/1272c19:dd:d9:dd:c25:c25:d00b:e09d
802c19:dd:d9:dd:c25:c25:d00b:e09e/1272c19:dd:d9:dd:c25:c25:d00b:e09f
812c19:dd:d9:dd:c25:c25:d00b:e0a0/1272c19:dd:d9:dd:c25:c25:d00b:e0a1
822c19:dd:d9:dd:c25:c25:d00b:e0a2/1272c19:dd:d9:dd:c25:c25:d00b:e0a3
832c19:dd:d9:dd:c25:c25:d00b:e0a4/1272c19:dd:d9:dd:c25:c25:d00b:e0a5
842c19:dd:d9:dd:c25:c25:d00b:e0a6/1272c19:dd:d9:dd:c25:c25:d00b:e0a7
852c19:dd:d9:dd:c25:c25:d00b:e0a8/1272c19:dd:d9:dd:c25:c25:d00b:e0a9
862c19:dd:d9:dd:c25:c25:d00b:e0aa/1272c19:dd:d9:dd:c25:c25:d00b:e0ab
872c19:dd:d9:dd:c25:c25:d00b:e0ac/1272c19:dd:d9:dd:c25:c25:d00b:e0ad
882c19:dd:d9:dd:c25:c25:d00b:e0ae/1272c19:dd:d9:dd:c25:c25:d00b:e0af
892c19:dd:d9:dd:c25:c25:d00b:e0b0/1272c19:dd:d9:dd:c25:c25:d00b:e0b1
902c19:dd:d9:dd:c25:c25:d00b:e0b2/1272c19:dd:d9:dd:c25:c25:d00b:e0b3
912c19:dd:d9:dd:c25:c25:d00b:e0b4/1272c19:dd:d9:dd:c25:c25:d00b:e0b5
922c19:dd:d9:dd:c25:c25:d00b:e0b6/1272c19:dd:d9:dd:c25:c25:d00b:e0b7
932c19:dd:d9:dd:c25:c25:d00b:e0b8/1272c19:dd:d9:dd:c25:c25:d00b:e0b9
942c19:dd:d9:dd:c25:c25:d00b:e0ba/1272c19:dd:d9:dd:c25:c25:d00b:e0bb
952c19:dd:d9:dd:c25:c25:d00b:e0bc/1272c19:dd:d9:dd:c25:c25:d00b:e0bd
962c19:dd:d9:dd:c25:c25:d00b:e0be/1272c19:dd:d9:dd:c25:c25:d00b:e0bf
972c19:dd:d9:dd:c25:c25:d00b:e0c0/1272c19:dd:d9:dd:c25:c25:d00b:e0c1
982c19:dd:d9:dd:c25:c25:d00b:e0c2/1272c19:dd:d9:dd:c25:c25:d00b:e0c3
992c19:dd:d9:dd:c25:c25:d00b:e0c4/1272c19:dd:d9:dd:c25:c25:d00b:e0c5
1002c19:dd:d9:dd:c25:c25:d00b:e0c6/1272c19:dd:d9:dd:c25:c25:d00b:e0c7
1012c19:dd:d9:dd:c25:c25:d00b:e0c8/1272c19:dd:d9:dd:c25:c25:d00b:e0c9
1022c19:dd:d9:dd:c25:c25:d00b:e0ca/1272c19:dd:d9:dd:c25:c25:d00b:e0cb
1032c19:dd:d9:dd:c25:c25:d00b:e0cc/1272c19:dd:d9:dd:c25:c25:d00b:e0cd
1042c19:dd:d9:dd:c25:c25:d00b:e0ce/1272c19:dd:d9:dd:c25:c25:d00b:e0cf
1052c19:dd:d9:dd:c25:c25:d00b:e0d0/1272c19:dd:d9:dd:c25:c25:d00b:e0d1
1062c19:dd:d9:dd:c25:c25:d00b:e0d2/1272c19:dd:d9:dd:c25:c25:d00b:e0d3
1072c19:dd:d9:dd:c25:c25:d00b:e0d4/1272c19:dd:d9:dd:c25:c25:d00b:e0d5
1082c19:dd:d9:dd:c25:c25:d00b:e0d6/1272c19:dd:d9:dd:c25:c25:d00b:e0d7
1092c19:dd:d9:dd:c25:c25:d00b:e0d8/1272c19:dd:d9:dd:c25:c25:d00b:e0d9
1102c19:dd:d9:dd:c25:c25:d00b:e0da/1272c19:dd:d9:dd:c25:c25:d00b:e0db
1112c19:dd:d9:dd:c25:c25:d00b:e0dc/1272c19:dd:d9:dd:c25:c25:d00b:e0dd
1122c19:dd:d9:dd:c25:c25:d00b:e0de/1272c19:dd:d9:dd:c25:c25:d00b:e0df
1132c19:dd:d9:dd:c25:c25:d00b:e0e0/1272c19:dd:d9:dd:c25:c25:d00b:e0e1
1142c19:dd:d9:dd:c25:c25:d00b:e0e2/1272c19:dd:d9:dd:c25:c25:d00b:e0e3
1152c19:dd:d9:dd:c25:c25:d00b:e0e4/1272c19:dd:d9:dd:c25:c25:d00b:e0e5
1162c19:dd:d9:dd:c25:c25:d00b:e0e6/1272c19:dd:d9:dd:c25:c25:d00b:e0e7
1172c19:dd:d9:dd:c25:c25:d00b:e0e8/1272c19:dd:d9:dd:c25:c25:d00b:e0e9
1182c19:dd:d9:dd:c25:c25:d00b:e0ea/1272c19:dd:d9:dd:c25:c25:d00b:e0eb
1192c19:dd:d9:dd:c25:c25:d00b:e0ec/1272c19:dd:d9:dd:c25:c25:d00b:e0ed
1202c19:dd:d9:dd:c25:c25:d00b:e0ee/1272c19:dd:d9:dd:c25:c25:d00b:e0ef
1212c19:dd:d9:dd:c25:c25:d00b:e0f0/1272c19:dd:d9:dd:c25:c25:d00b:e0f1
1222c19:dd:d9:dd:c25:c25:d00b:e0f2/1272c19:dd:d9:dd:c25:c25:d00b:e0f3
1232c19:dd:d9:dd:c25:c25:d00b:e0f4/1272c19:dd:d9:dd:c25:c25:d00b:e0f5
1242c19:dd:d9:dd:c25:c25:d00b:e0f6/1272c19:dd:d9:dd:c25:c25:d00b:e0f7
1252c19:dd:d9:dd:c25:c25:d00b:e0f8/1272c19:dd:d9:dd:c25:c25:d00b:e0f9
1262c19:dd:d9:dd:c25:c25:d00b:e0fa/1272c19:dd:d9:dd:c25:c25:d00b:e0fb
1272c19:dd:d9:dd:c25:c25:d00b:e0fc/1272c19:dd:d9:dd:c25:c25:d00b:e0fd
1282c19:dd:d9:dd:c25:c25:d00b:e0fe/1272c19:dd:d9:dd:c25:c25:d00b:e0ff
1292c19:dd:d9:dd:c25:c25:d00b:e100/1272c19:dd:d9:dd:c25:c25:d00b:e101
1302c19:dd:d9:dd:c25:c25:d00b:e102/1272c19:dd:d9:dd:c25:c25:d00b:e103
1312c19:dd:d9:dd:c25:c25:d00b:e104/1272c19:dd:d9:dd:c25:c25:d00b:e105
1322c19:dd:d9:dd:c25:c25:d00b:e106/1272c19:dd:d9:dd:c25:c25:d00b:e107
1332c19:dd:d9:dd:c25:c25:d00b:e108/1272c19:dd:d9:dd:c25:c25:d00b:e109
1342c19:dd:d9:dd:c25:c25:d00b:e10a/1272c19:dd:d9:dd:c25:c25:d00b:e10b
1352c19:dd:d9:dd:c25:c25:d00b:e10c/1272c19:dd:d9:dd:c25:c25:d00b:e10d
1362c19:dd:d9:dd:c25:c25:d00b:e10e/1272c19:dd:d9:dd:c25:c25:d00b:e10f
1372c19:dd:d9:dd:c25:c25:d00b:e110/1272c19:dd:d9:dd:c25:c25:d00b:e111
1382c19:dd:d9:dd:c25:c25:d00b:e112/1272c19:dd:d9:dd:c25:c25:d00b:e113
1392c19:dd:d9:dd:c25:c25:d00b:e114/1272c19:dd:d9:dd:c25:c25:d00b:e115
1402c19:dd:d9:dd:c25:c25:d00b:e116/1272c19:dd:d9:dd:c25:c25:d00b:e117
1412c19:dd:d9:dd:c25:c25:d00b:e118/1272c19:dd:d9:dd:c25:c25:d00b:e119
1422c19:dd:d9:dd:c25:c25:d00b:e11a/1272c19:dd:d9:dd:c25:c25:d00b:e11b
1432c19:dd:d9:dd:c25:c25:d00b:e11c/1272c19:dd:d9:dd:c25:c25:d00b:e11d
1442c19:dd:d9:dd:c25:c25:d00b:e11e/1272c19:dd:d9:dd:c25:c25:d00b:e11f
1452c19:dd:d9:dd:c25:c25:d00b:e120/1272c19:dd:d9:dd:c25:c25:d00b:e121
1462c19:dd:d9:dd:c25:c25:d00b:e122/1272c19:dd:d9:dd:c25:c25:d00b:e123
1472c19:dd:d9:dd:c25:c25:d00b:e124/1272c19:dd:d9:dd:c25:c25:d00b:e125
1482c19:dd:d9:dd:c25:c25:d00b:e126/1272c19:dd:d9:dd:c25:c25:d00b:e127
1492c19:dd:d9:dd:c25:c25:d00b:e128/1272c19:dd:d9:dd:c25:c25:d00b:e129
1502c19:dd:d9:dd:c25:c25:d00b:e12a/1272c19:dd:d9:dd:c25:c25:d00b:e12b
1512c19:dd:d9:dd:c25:c25:d00b:e12c/1272c19:dd:d9:dd:c25:c25:d00b:e12d
1522c19:dd:d9:dd:c25:c25:d00b:e12e/1272c19:dd:d9:dd:c25:c25:d00b:e12f
1532c19:dd:d9:dd:c25:c25:d00b:e130/1272c19:dd:d9:dd:c25:c25:d00b:e131
1542c19:dd:d9:dd:c25:c25:d00b:e132/1272c19:dd:d9:dd:c25:c25:d00b:e133
1552c19:dd:d9:dd:c25:c25:d00b:e134/1272c19:dd:d9:dd:c25:c25:d00b:e135
1562c19:dd:d9:dd:c25:c25:d00b:e136/1272c19:dd:d9:dd:c25:c25:d00b:e137
1572c19:dd:d9:dd:c25:c25:d00b:e138/1272c19:dd:d9:dd:c25:c25:d00b:e139
1582c19:dd:d9:dd:c25:c25:d00b:e13a/1272c19:dd:d9:dd:c25:c25:d00b:e13b
1592c19:dd:d9:dd:c25:c25:d00b:e13c/1272c19:dd:d9:dd:c25:c25:d00b:e13d
1602c19:dd:d9:dd:c25:c25:d00b:e13e/1272c19:dd:d9:dd:c25:c25:d00b:e13f
1612c19:dd:d9:dd:c25:c25:d00b:e140/1272c19:dd:d9:dd:c25:c25:d00b:e141
1622c19:dd:d9:dd:c25:c25:d00b:e142/1272c19:dd:d9:dd:c25:c25:d00b:e143
1632c19:dd:d9:dd:c25:c25:d00b:e144/1272c19:dd:d9:dd:c25:c25:d00b:e145
1642c19:dd:d9:dd:c25:c25:d00b:e146/1272c19:dd:d9:dd:c25:c25:d00b:e147
1652c19:dd:d9:dd:c25:c25:d00b:e148/1272c19:dd:d9:dd:c25:c25:d00b:e149
1662c19:dd:d9:dd:c25:c25:d00b:e14a/1272c19:dd:d9:dd:c25:c25:d00b:e14b
1672c19:dd:d9:dd:c25:c25:d00b:e14c/1272c19:dd:d9:dd:c25:c25:d00b:e14d
1682c19:dd:d9:dd:c25:c25:d00b:e14e/1272c19:dd:d9:dd:c25:c25:d00b:e14f
1692c19:dd:d9:dd:c25:c25:d00b:e150/1272c19:dd:d9:dd:c25:c25:d00b:e151
1702c19:dd:d9:dd:c25:c25:d00b:e152/1272c19:dd:d9:dd:c25:c25:d00b:e153
1712c19:dd:d9:dd:c25:c25:d00b:e154/1272c19:dd:d9:dd:c25:c25:d00b:e155
1722c19:dd:d9:dd:c25:c25:d00b:e156/1272c19:dd:d9:dd:c25:c25:d00b:e157
1732c19:dd:d9:dd:c25:c25:d00b:e158/1272c19:dd:d9:dd:c25:c25:d00b:e159
1742c19:dd:d9:dd:c25:c25:d00b:e15a/1272c19:dd:d9:dd:c25:c25:d00b:e15b
1752c19:dd:d9:dd:c25:c25:d00b:e15c/1272c19:dd:d9:dd:c25:c25:d00b:e15d
1762c19:dd:d9:dd:c25:c25:d00b:e15e/1272c19:dd:d9:dd:c25:c25:d00b:e15f
1772c19:dd:d9:dd:c25:c25:d00b:e160/1272c19:dd:d9:dd:c25:c25:d00b:e161
1782c19:dd:d9:dd:c25:c25:d00b:e162/1272c19:dd:d9:dd:c25:c25:d00b:e163
1792c19:dd:d9:dd:c25:c25:d00b:e164/1272c19:dd:d9:dd:c25:c25:d00b:e165
1802c19:dd:d9:dd:c25:c25:d00b:e166/1272c19:dd:d9:dd:c25:c25:d00b:e167
1812c19:dd:d9:dd:c25:c25:d00b:e168/1272c19:dd:d9:dd:c25:c25:d00b:e169
1822c19:dd:d9:dd:c25:c25:d00b:e16a/1272c19:dd:d9:dd:c25:c25:d00b:e16b
1832c19:dd:d9:dd:c25:c25:d00b:e16c/1272c19:dd:d9:dd:c25:c25:d00b:e16d
1842c19:dd:d9:dd:c25:c25:d00b:e16e/1272c19:dd:d9:dd:c25:c25:d00b:e16f
1852c19:dd:d9:dd:c25:c25:d00b:e170/1272c19:dd:d9:dd:c25:c25:d00b:e171
1862c19:dd:d9:dd:c25:c25:d00b:e172/1272c19:dd:d9:dd:c25:c25:d00b:e173
1872c19:dd:d9:dd:c25:c25:d00b:e174/1272c19:dd:d9:dd:c25:c25:d00b:e175
1882c19:dd:d9:dd:c25:c25:d00b:e176/1272c19:dd:d9:dd:c25:c25:d00b:e177
1892c19:dd:d9:dd:c25:c25:d00b:e178/1272c19:dd:d9:dd:c25:c25:d00b:e179
1902c19:dd:d9:dd:c25:c25:d00b:e17a/1272c19:dd:d9:dd:c25:c25:d00b:e17b
1912c19:dd:d9:dd:c25:c25:d00b:e17c/1272c19:dd:d9:dd:c25:c25:d00b:e17d
1922c19:dd:d9:dd:c25:c25:d00b:e17e/1272c19:dd:d9:dd:c25:c25:d00b:e17f
1932c19:dd:d9:dd:c25:c25:d00b:e180/1272c19:dd:d9:dd:c25:c25:d00b:e181
1942c19:dd:d9:dd:c25:c25:d00b:e182/1272c19:dd:d9:dd:c25:c25:d00b:e183
1952c19:dd:d9:dd:c25:c25:d00b:e184/1272c19:dd:d9:dd:c25:c25:d00b:e185
1962c19:dd:d9:dd:c25:c25:d00b:e186/1272c19:dd:d9:dd:c25:c25:d00b:e187
1972c19:dd:d9:dd:c25:c25:d00b:e188/1272c19:dd:d9:dd:c25:c25:d00b:e189
1982c19:dd:d9:dd:c25:c25:d00b:e18a/1272c19:dd:d9:dd:c25:c25:d00b:e18b
1992c19:dd:d9:dd:c25:c25:d00b:e18c/1272c19:dd:d9:dd:c25:c25:d00b:e18d
2002c19:dd:d9:dd:c25:c25:d00b:e18e/1272c19:dd:d9:dd:c25:c25:d00b:e18f
2012c19:dd:d9:dd:c25:c25:d00b:e190/1272c19:dd:d9:dd:c25:c25:d00b:e191
2022c19:dd:d9:dd:c25:c25:d00b:e192/1272c19:dd:d9:dd:c25:c25:d00b:e193
2032c19:dd:d9:dd:c25:c25:d00b:e194/1272c19:dd:d9:dd:c25:c25:d00b:e195
2042c19:dd:d9:dd:c25:c25:d00b:e196/1272c19:dd:d9:dd:c25:c25:d00b:e197
2052c19:dd:d9:dd:c25:c25:d00b:e198/1272c19:dd:d9:dd:c25:c25:d00b:e199
2062c19:dd:d9:dd:c25:c25:d00b:e19a/1272c19:dd:d9:dd:c25:c25:d00b:e19b
2072c19:dd:d9:dd:c25:c25:d00b:e19c/1272c19:dd:d9:dd:c25:c25:d00b:e19d
2082c19:dd:d9:dd:c25:c25:d00b:e19e/1272c19:dd:d9:dd:c25:c25:d00b:e19f
2092c19:dd:d9:dd:c25:c25:d00b:e1a0/1272c19:dd:d9:dd:c25:c25:d00b:e1a1
2102c19:dd:d9:dd:c25:c25:d00b:e1a2/1272c19:dd:d9:dd:c25:c25:d00b:e1a3
2112c19:dd:d9:dd:c25:c25:d00b:e1a4/1272c19:dd:d9:dd:c25:c25:d00b:e1a5
2122c19:dd:d9:dd:c25:c25:d00b:e1a6/1272c19:dd:d9:dd:c25:c25:d00b:e1a7
2132c19:dd:d9:dd:c25:c25:d00b:e1a8/1272c19:dd:d9:dd:c25:c25:d00b:e1a9
2142c19:dd:d9:dd:c25:c25:d00b:e1aa/1272c19:dd:d9:dd:c25:c25:d00b:e1ab
2152c19:dd:d9:dd:c25:c25:d00b:e1ac/1272c19:dd:d9:dd:c25:c25:d00b:e1ad
2162c19:dd:d9:dd:c25:c25:d00b:e1ae/1272c19:dd:d9:dd:c25:c25:d00b:e1af
2172c19:dd:d9:dd:c25:c25:d00b:e1b0/1272c19:dd:d9:dd:c25:c25:d00b:e1b1
2182c19:dd:d9:dd:c25:c25:d00b:e1b2/1272c19:dd:d9:dd:c25:c25:d00b:e1b3
2192c19:dd:d9:dd:c25:c25:d00b:e1b4/1272c19:dd:d9:dd:c25:c25:d00b:e1b5
2202c19:dd:d9:dd:c25:c25:d00b:e1b6/1272c19:dd:d9:dd:c25:c25:d00b:e1b7
2212c19:dd:d9:dd:c25:c25:d00b:e1b8/1272c19:dd:d9:dd:c25:c25:d00b:e1b9
2222c19:dd:d9:dd:c25:c25:d00b:e1ba/1272c19:dd:d9:dd:c25:c25:d00b:e1bb
2232c19:dd:d9:dd:c25:c25:d00b:e1bc/1272c19:dd:d9:dd:c25:c25:d00b:e1bd
2242c19:dd:d9:dd:c25:c25:d00b:e1be/1272c19:dd:d9:dd:c25:c25:d00b:e1bf
2252c19:dd:d9:dd:c25:c25:d00b:e1c0/1272c19:dd:d9:dd:c25:c25:d00b:e1c1
2262c19:dd:d9:dd:c25:c25:d00b:e1c2/1272c19:dd:d9:dd:c25:c25:d00b:e1c3
2272c19:dd:d9:dd:c25:c25:d00b:e1c4/1272c19:dd:d9:dd:c25:c25:d00b:e1c5
2282c19:dd:d9:dd:c25:c25:d00b:e1c6/1272c19:dd:d9:dd:c25:c25:d00b:e1c7
2292c19:dd:d9:dd:c25:c25:d00b:e1c8/1272c19:dd:d9:dd:c25:c25:d00b:e1c9
2302c19:dd:d9:dd:c25:c25:d00b:e1ca/1272c19:dd:d9:dd:c25:c25:d00b:e1cb
2312c19:dd:d9:dd:c25:c25:d00b:e1cc/1272c19:dd:d9:dd:c25:c25:d00b:e1cd
2322c19:dd:d9:dd:c25:c25:d00b:e1ce/1272c19:dd:d9:dd:c25:c25:d00b:e1cf
2332c19:dd:d9:dd:c25:c25:d00b:e1d0/1272c19:dd:d9:dd:c25:c25:d00b:e1d1
2342c19:dd:d9:dd:c25:c25:d00b:e1d2/1272c19:dd:d9:dd:c25:c25:d00b:e1d3
2352c19:dd:d9:dd:c25:c25:d00b:e1d4/1272c19:dd:d9:dd:c25:c25:d00b:e1d5
2362c19:dd:d9:dd:c25:c25:d00b:e1d6/1272c19:dd:d9:dd:c25:c25:d00b:e1d7
2372c19:dd:d9:dd:c25:c25:d00b:e1d8/1272c19:dd:d9:dd:c25:c25:d00b:e1d9
2382c19:dd:d9:dd:c25:c25:d00b:e1da/1272c19:dd:d9:dd:c25:c25:d00b:e1db
2392c19:dd:d9:dd:c25:c25:d00b:e1dc/1272c19:dd:d9:dd:c25:c25:d00b:e1dd
2402c19:dd:d9:dd:c25:c25:d00b:e1de/1272c19:dd:d9:dd:c25:c25:d00b:e1df
2412c19:dd:d9:dd:c25:c25:d00b:e1e0/1272c19:dd:d9:dd:c25:c25:d00b:e1e1
2422c19:dd:d9:dd:c25:c25:d00b:e1e2/1272c19:dd:d9:dd:c25:c25:d00b:e1e3
2432c19:dd:d9:dd:c25:c25:d00b:e1e4/1272c19:dd:d9:dd:c25:c25:d00b:e1e5
2442c19:dd:d9:dd:c25:c25:d00b:e1e6/1272c19:dd:d9:dd:c25:c25:d00b:e1e7
2452c19:dd:d9:dd:c25:c25:d00b:e1e8/1272c19:dd:d9:dd:c25:c25:d00b:e1e9
2462c19:dd:d9:dd:c25:c25:d00b:e1ea/1272c19:dd:d9:dd:c25:c25:d00b:e1eb
2472c19:dd:d9:dd:c25:c25:d00b:e1ec/1272c19:dd:d9:dd:c25:c25:d00b:e1ed
2482c19:dd:d9:dd:c25:c25:d00b:e1ee/1272c19:dd:d9:dd:c25:c25:d00b:e1ef
2492c19:dd:d9:dd:c25:c25:d00b:e1f0/1272c19:dd:d9:dd:c25:c25:d00b:e1f1
2502c19:dd:d9:dd:c25:c25:d00b:e1f2/1272c19:dd:d9:dd:c25:c25:d00b:e1f3
2512c19:dd:d9:dd:c25:c25:d00b:e1f4/1272c19:dd:d9:dd:c25:c25:d00b:e1f5
2522c19:dd:d9:dd:c25:c25:d00b:e1f6/1272c19:dd:d9:dd:c25:c25:d00b:e1f7
2532c19:dd:d9:dd:c25:c25:d00b:e1f8/1272c19:dd:d9:dd:c25:c25:d00b:e1f9
2542c19:dd:d9:dd:c25:c25:d00b:e1fa/1272c19:dd:d9:dd:c25:c25:d00b:e1fb
2552c19:dd:d9:dd:c25:c25:d00b:e1fc/1272c19:dd:d9:dd:c25:c25:d00b:e1fd
2562c19:dd:d9:dd:c25:c25:d00b:e1fe/1272c19:dd:d9:dd:c25:c25:d00b:e1ff

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.