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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:c25a:d00a:e100/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:e100
Last address
2c19:dd:d9:dd:c25:c25a:d00a:e1ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:e100
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
1.e.a.0.0.d.a.5.2.c.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:c25a:d00a:e100/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:e100/1282c19:dd:d9:dd:c25:c25a:d00a:e100
22c19:dd:d9:dd:c25:c25a:d00a:e101/1282c19:dd:d9:dd:c25:c25a:d00a:e101
32c19:dd:d9:dd:c25:c25a:d00a:e102/1282c19:dd:d9:dd:c25:c25a:d00a:e102
42c19:dd:d9:dd:c25:c25a:d00a:e103/1282c19:dd:d9:dd:c25:c25a:d00a:e103
52c19:dd:d9:dd:c25:c25a:d00a:e104/1282c19:dd:d9:dd:c25:c25a:d00a:e104
62c19:dd:d9:dd:c25:c25a:d00a:e105/1282c19:dd:d9:dd:c25:c25a:d00a:e105
72c19:dd:d9:dd:c25:c25a:d00a:e106/1282c19:dd:d9:dd:c25:c25a:d00a:e106
82c19:dd:d9:dd:c25:c25a:d00a:e107/1282c19:dd:d9:dd:c25:c25a:d00a:e107
92c19:dd:d9:dd:c25:c25a:d00a:e108/1282c19:dd:d9:dd:c25:c25a:d00a:e108
102c19:dd:d9:dd:c25:c25a:d00a:e109/1282c19:dd:d9:dd:c25:c25a:d00a:e109
112c19:dd:d9:dd:c25:c25a:d00a:e10a/1282c19:dd:d9:dd:c25:c25a:d00a:e10a
122c19:dd:d9:dd:c25:c25a:d00a:e10b/1282c19:dd:d9:dd:c25:c25a:d00a:e10b
132c19:dd:d9:dd:c25:c25a:d00a:e10c/1282c19:dd:d9:dd:c25:c25a:d00a:e10c
142c19:dd:d9:dd:c25:c25a:d00a:e10d/1282c19:dd:d9:dd:c25:c25a:d00a:e10d
152c19:dd:d9:dd:c25:c25a:d00a:e10e/1282c19:dd:d9:dd:c25:c25a:d00a:e10e
162c19:dd:d9:dd:c25:c25a:d00a:e10f/1282c19:dd:d9:dd:c25:c25a:d00a:e10f
172c19:dd:d9:dd:c25:c25a:d00a:e110/1282c19:dd:d9:dd:c25:c25a:d00a:e110
182c19:dd:d9:dd:c25:c25a:d00a:e111/1282c19:dd:d9:dd:c25:c25a:d00a:e111
192c19:dd:d9:dd:c25:c25a:d00a:e112/1282c19:dd:d9:dd:c25:c25a:d00a:e112
202c19:dd:d9:dd:c25:c25a:d00a:e113/1282c19:dd:d9:dd:c25:c25a:d00a:e113
212c19:dd:d9:dd:c25:c25a:d00a:e114/1282c19:dd:d9:dd:c25:c25a:d00a:e114
222c19:dd:d9:dd:c25:c25a:d00a:e115/1282c19:dd:d9:dd:c25:c25a:d00a:e115
232c19:dd:d9:dd:c25:c25a:d00a:e116/1282c19:dd:d9:dd:c25:c25a:d00a:e116
242c19:dd:d9:dd:c25:c25a:d00a:e117/1282c19:dd:d9:dd:c25:c25a:d00a:e117
252c19:dd:d9:dd:c25:c25a:d00a:e118/1282c19:dd:d9:dd:c25:c25a:d00a:e118
262c19:dd:d9:dd:c25:c25a:d00a:e119/1282c19:dd:d9:dd:c25:c25a:d00a:e119
272c19:dd:d9:dd:c25:c25a:d00a:e11a/1282c19:dd:d9:dd:c25:c25a:d00a:e11a
282c19:dd:d9:dd:c25:c25a:d00a:e11b/1282c19:dd:d9:dd:c25:c25a:d00a:e11b
292c19:dd:d9:dd:c25:c25a:d00a:e11c/1282c19:dd:d9:dd:c25:c25a:d00a:e11c
302c19:dd:d9:dd:c25:c25a:d00a:e11d/1282c19:dd:d9:dd:c25:c25a:d00a:e11d
312c19:dd:d9:dd:c25:c25a:d00a:e11e/1282c19:dd:d9:dd:c25:c25a:d00a:e11e
322c19:dd:d9:dd:c25:c25a:d00a:e11f/1282c19:dd:d9:dd:c25:c25a:d00a:e11f
332c19:dd:d9:dd:c25:c25a:d00a:e120/1282c19:dd:d9:dd:c25:c25a:d00a:e120
342c19:dd:d9:dd:c25:c25a:d00a:e121/1282c19:dd:d9:dd:c25:c25a:d00a:e121
352c19:dd:d9:dd:c25:c25a:d00a:e122/1282c19:dd:d9:dd:c25:c25a:d00a:e122
362c19:dd:d9:dd:c25:c25a:d00a:e123/1282c19:dd:d9:dd:c25:c25a:d00a:e123
372c19:dd:d9:dd:c25:c25a:d00a:e124/1282c19:dd:d9:dd:c25:c25a:d00a:e124
382c19:dd:d9:dd:c25:c25a:d00a:e125/1282c19:dd:d9:dd:c25:c25a:d00a:e125
392c19:dd:d9:dd:c25:c25a:d00a:e126/1282c19:dd:d9:dd:c25:c25a:d00a:e126
402c19:dd:d9:dd:c25:c25a:d00a:e127/1282c19:dd:d9:dd:c25:c25a:d00a:e127
412c19:dd:d9:dd:c25:c25a:d00a:e128/1282c19:dd:d9:dd:c25:c25a:d00a:e128
422c19:dd:d9:dd:c25:c25a:d00a:e129/1282c19:dd:d9:dd:c25:c25a:d00a:e129
432c19:dd:d9:dd:c25:c25a:d00a:e12a/1282c19:dd:d9:dd:c25:c25a:d00a:e12a
442c19:dd:d9:dd:c25:c25a:d00a:e12b/1282c19:dd:d9:dd:c25:c25a:d00a:e12b
452c19:dd:d9:dd:c25:c25a:d00a:e12c/1282c19:dd:d9:dd:c25:c25a:d00a:e12c
462c19:dd:d9:dd:c25:c25a:d00a:e12d/1282c19:dd:d9:dd:c25:c25a:d00a:e12d
472c19:dd:d9:dd:c25:c25a:d00a:e12e/1282c19:dd:d9:dd:c25:c25a:d00a:e12e
482c19:dd:d9:dd:c25:c25a:d00a:e12f/1282c19:dd:d9:dd:c25:c25a:d00a:e12f
492c19:dd:d9:dd:c25:c25a:d00a:e130/1282c19:dd:d9:dd:c25:c25a:d00a:e130
502c19:dd:d9:dd:c25:c25a:d00a:e131/1282c19:dd:d9:dd:c25:c25a:d00a:e131
512c19:dd:d9:dd:c25:c25a:d00a:e132/1282c19:dd:d9:dd:c25:c25a:d00a:e132
522c19:dd:d9:dd:c25:c25a:d00a:e133/1282c19:dd:d9:dd:c25:c25a:d00a:e133
532c19:dd:d9:dd:c25:c25a:d00a:e134/1282c19:dd:d9:dd:c25:c25a:d00a:e134
542c19:dd:d9:dd:c25:c25a:d00a:e135/1282c19:dd:d9:dd:c25:c25a:d00a:e135
552c19:dd:d9:dd:c25:c25a:d00a:e136/1282c19:dd:d9:dd:c25:c25a:d00a:e136
562c19:dd:d9:dd:c25:c25a:d00a:e137/1282c19:dd:d9:dd:c25:c25a:d00a:e137
572c19:dd:d9:dd:c25:c25a:d00a:e138/1282c19:dd:d9:dd:c25:c25a:d00a:e138
582c19:dd:d9:dd:c25:c25a:d00a:e139/1282c19:dd:d9:dd:c25:c25a:d00a:e139
592c19:dd:d9:dd:c25:c25a:d00a:e13a/1282c19:dd:d9:dd:c25:c25a:d00a:e13a
602c19:dd:d9:dd:c25:c25a:d00a:e13b/1282c19:dd:d9:dd:c25:c25a:d00a:e13b
612c19:dd:d9:dd:c25:c25a:d00a:e13c/1282c19:dd:d9:dd:c25:c25a:d00a:e13c
622c19:dd:d9:dd:c25:c25a:d00a:e13d/1282c19:dd:d9:dd:c25:c25a:d00a:e13d
632c19:dd:d9:dd:c25:c25a:d00a:e13e/1282c19:dd:d9:dd:c25:c25a:d00a:e13e
642c19:dd:d9:dd:c25:c25a:d00a:e13f/1282c19:dd:d9:dd:c25:c25a:d00a:e13f
652c19:dd:d9:dd:c25:c25a:d00a:e140/1282c19:dd:d9:dd:c25:c25a:d00a:e140
662c19:dd:d9:dd:c25:c25a:d00a:e141/1282c19:dd:d9:dd:c25:c25a:d00a:e141
672c19:dd:d9:dd:c25:c25a:d00a:e142/1282c19:dd:d9:dd:c25:c25a:d00a:e142
682c19:dd:d9:dd:c25:c25a:d00a:e143/1282c19:dd:d9:dd:c25:c25a:d00a:e143
692c19:dd:d9:dd:c25:c25a:d00a:e144/1282c19:dd:d9:dd:c25:c25a:d00a:e144
702c19:dd:d9:dd:c25:c25a:d00a:e145/1282c19:dd:d9:dd:c25:c25a:d00a:e145
712c19:dd:d9:dd:c25:c25a:d00a:e146/1282c19:dd:d9:dd:c25:c25a:d00a:e146
722c19:dd:d9:dd:c25:c25a:d00a:e147/1282c19:dd:d9:dd:c25:c25a:d00a:e147
732c19:dd:d9:dd:c25:c25a:d00a:e148/1282c19:dd:d9:dd:c25:c25a:d00a:e148
742c19:dd:d9:dd:c25:c25a:d00a:e149/1282c19:dd:d9:dd:c25:c25a:d00a:e149
752c19:dd:d9:dd:c25:c25a:d00a:e14a/1282c19:dd:d9:dd:c25:c25a:d00a:e14a
762c19:dd:d9:dd:c25:c25a:d00a:e14b/1282c19:dd:d9:dd:c25:c25a:d00a:e14b
772c19:dd:d9:dd:c25:c25a:d00a:e14c/1282c19:dd:d9:dd:c25:c25a:d00a:e14c
782c19:dd:d9:dd:c25:c25a:d00a:e14d/1282c19:dd:d9:dd:c25:c25a:d00a:e14d
792c19:dd:d9:dd:c25:c25a:d00a:e14e/1282c19:dd:d9:dd:c25:c25a:d00a:e14e
802c19:dd:d9:dd:c25:c25a:d00a:e14f/1282c19:dd:d9:dd:c25:c25a:d00a:e14f
812c19:dd:d9:dd:c25:c25a:d00a:e150/1282c19:dd:d9:dd:c25:c25a:d00a:e150
822c19:dd:d9:dd:c25:c25a:d00a:e151/1282c19:dd:d9:dd:c25:c25a:d00a:e151
832c19:dd:d9:dd:c25:c25a:d00a:e152/1282c19:dd:d9:dd:c25:c25a:d00a:e152
842c19:dd:d9:dd:c25:c25a:d00a:e153/1282c19:dd:d9:dd:c25:c25a:d00a:e153
852c19:dd:d9:dd:c25:c25a:d00a:e154/1282c19:dd:d9:dd:c25:c25a:d00a:e154
862c19:dd:d9:dd:c25:c25a:d00a:e155/1282c19:dd:d9:dd:c25:c25a:d00a:e155
872c19:dd:d9:dd:c25:c25a:d00a:e156/1282c19:dd:d9:dd:c25:c25a:d00a:e156
882c19:dd:d9:dd:c25:c25a:d00a:e157/1282c19:dd:d9:dd:c25:c25a:d00a:e157
892c19:dd:d9:dd:c25:c25a:d00a:e158/1282c19:dd:d9:dd:c25:c25a:d00a:e158
902c19:dd:d9:dd:c25:c25a:d00a:e159/1282c19:dd:d9:dd:c25:c25a:d00a:e159
912c19:dd:d9:dd:c25:c25a:d00a:e15a/1282c19:dd:d9:dd:c25:c25a:d00a:e15a
922c19:dd:d9:dd:c25:c25a:d00a:e15b/1282c19:dd:d9:dd:c25:c25a:d00a:e15b
932c19:dd:d9:dd:c25:c25a:d00a:e15c/1282c19:dd:d9:dd:c25:c25a:d00a:e15c
942c19:dd:d9:dd:c25:c25a:d00a:e15d/1282c19:dd:d9:dd:c25:c25a:d00a:e15d
952c19:dd:d9:dd:c25:c25a:d00a:e15e/1282c19:dd:d9:dd:c25:c25a:d00a:e15e
962c19:dd:d9:dd:c25:c25a:d00a:e15f/1282c19:dd:d9:dd:c25:c25a:d00a:e15f
972c19:dd:d9:dd:c25:c25a:d00a:e160/1282c19:dd:d9:dd:c25:c25a:d00a:e160
982c19:dd:d9:dd:c25:c25a:d00a:e161/1282c19:dd:d9:dd:c25:c25a:d00a:e161
992c19:dd:d9:dd:c25:c25a:d00a:e162/1282c19:dd:d9:dd:c25:c25a:d00a:e162
1002c19:dd:d9:dd:c25:c25a:d00a:e163/1282c19:dd:d9:dd:c25:c25a:d00a:e163
1012c19:dd:d9:dd:c25:c25a:d00a:e164/1282c19:dd:d9:dd:c25:c25a:d00a:e164
1022c19:dd:d9:dd:c25:c25a:d00a:e165/1282c19:dd:d9:dd:c25:c25a:d00a:e165
1032c19:dd:d9:dd:c25:c25a:d00a:e166/1282c19:dd:d9:dd:c25:c25a:d00a:e166
1042c19:dd:d9:dd:c25:c25a:d00a:e167/1282c19:dd:d9:dd:c25:c25a:d00a:e167
1052c19:dd:d9:dd:c25:c25a:d00a:e168/1282c19:dd:d9:dd:c25:c25a:d00a:e168
1062c19:dd:d9:dd:c25:c25a:d00a:e169/1282c19:dd:d9:dd:c25:c25a:d00a:e169
1072c19:dd:d9:dd:c25:c25a:d00a:e16a/1282c19:dd:d9:dd:c25:c25a:d00a:e16a
1082c19:dd:d9:dd:c25:c25a:d00a:e16b/1282c19:dd:d9:dd:c25:c25a:d00a:e16b
1092c19:dd:d9:dd:c25:c25a:d00a:e16c/1282c19:dd:d9:dd:c25:c25a:d00a:e16c
1102c19:dd:d9:dd:c25:c25a:d00a:e16d/1282c19:dd:d9:dd:c25:c25a:d00a:e16d
1112c19:dd:d9:dd:c25:c25a:d00a:e16e/1282c19:dd:d9:dd:c25:c25a:d00a:e16e
1122c19:dd:d9:dd:c25:c25a:d00a:e16f/1282c19:dd:d9:dd:c25:c25a:d00a:e16f
1132c19:dd:d9:dd:c25:c25a:d00a:e170/1282c19:dd:d9:dd:c25:c25a:d00a:e170
1142c19:dd:d9:dd:c25:c25a:d00a:e171/1282c19:dd:d9:dd:c25:c25a:d00a:e171
1152c19:dd:d9:dd:c25:c25a:d00a:e172/1282c19:dd:d9:dd:c25:c25a:d00a:e172
1162c19:dd:d9:dd:c25:c25a:d00a:e173/1282c19:dd:d9:dd:c25:c25a:d00a:e173
1172c19:dd:d9:dd:c25:c25a:d00a:e174/1282c19:dd:d9:dd:c25:c25a:d00a:e174
1182c19:dd:d9:dd:c25:c25a:d00a:e175/1282c19:dd:d9:dd:c25:c25a:d00a:e175
1192c19:dd:d9:dd:c25:c25a:d00a:e176/1282c19:dd:d9:dd:c25:c25a:d00a:e176
1202c19:dd:d9:dd:c25:c25a:d00a:e177/1282c19:dd:d9:dd:c25:c25a:d00a:e177
1212c19:dd:d9:dd:c25:c25a:d00a:e178/1282c19:dd:d9:dd:c25:c25a:d00a:e178
1222c19:dd:d9:dd:c25:c25a:d00a:e179/1282c19:dd:d9:dd:c25:c25a:d00a:e179
1232c19:dd:d9:dd:c25:c25a:d00a:e17a/1282c19:dd:d9:dd:c25:c25a:d00a:e17a
1242c19:dd:d9:dd:c25:c25a:d00a:e17b/1282c19:dd:d9:dd:c25:c25a:d00a:e17b
1252c19:dd:d9:dd:c25:c25a:d00a:e17c/1282c19:dd:d9:dd:c25:c25a:d00a:e17c
1262c19:dd:d9:dd:c25:c25a:d00a:e17d/1282c19:dd:d9:dd:c25:c25a:d00a:e17d
1272c19:dd:d9:dd:c25:c25a:d00a:e17e/1282c19:dd:d9:dd:c25:c25a:d00a:e17e
1282c19:dd:d9:dd:c25:c25a:d00a:e17f/1282c19:dd:d9:dd:c25:c25a:d00a:e17f
1292c19:dd:d9:dd:c25:c25a:d00a:e180/1282c19:dd:d9:dd:c25:c25a:d00a:e180
1302c19:dd:d9:dd:c25:c25a:d00a:e181/1282c19:dd:d9:dd:c25:c25a:d00a:e181
1312c19:dd:d9:dd:c25:c25a:d00a:e182/1282c19:dd:d9:dd:c25:c25a:d00a:e182
1322c19:dd:d9:dd:c25:c25a:d00a:e183/1282c19:dd:d9:dd:c25:c25a:d00a:e183
1332c19:dd:d9:dd:c25:c25a:d00a:e184/1282c19:dd:d9:dd:c25:c25a:d00a:e184
1342c19:dd:d9:dd:c25:c25a:d00a:e185/1282c19:dd:d9:dd:c25:c25a:d00a:e185
1352c19:dd:d9:dd:c25:c25a:d00a:e186/1282c19:dd:d9:dd:c25:c25a:d00a:e186
1362c19:dd:d9:dd:c25:c25a:d00a:e187/1282c19:dd:d9:dd:c25:c25a:d00a:e187
1372c19:dd:d9:dd:c25:c25a:d00a:e188/1282c19:dd:d9:dd:c25:c25a:d00a:e188
1382c19:dd:d9:dd:c25:c25a:d00a:e189/1282c19:dd:d9:dd:c25:c25a:d00a:e189
1392c19:dd:d9:dd:c25:c25a:d00a:e18a/1282c19:dd:d9:dd:c25:c25a:d00a:e18a
1402c19:dd:d9:dd:c25:c25a:d00a:e18b/1282c19:dd:d9:dd:c25:c25a:d00a:e18b
1412c19:dd:d9:dd:c25:c25a:d00a:e18c/1282c19:dd:d9:dd:c25:c25a:d00a:e18c
1422c19:dd:d9:dd:c25:c25a:d00a:e18d/1282c19:dd:d9:dd:c25:c25a:d00a:e18d
1432c19:dd:d9:dd:c25:c25a:d00a:e18e/1282c19:dd:d9:dd:c25:c25a:d00a:e18e
1442c19:dd:d9:dd:c25:c25a:d00a:e18f/1282c19:dd:d9:dd:c25:c25a:d00a:e18f
1452c19:dd:d9:dd:c25:c25a:d00a:e190/1282c19:dd:d9:dd:c25:c25a:d00a:e190
1462c19:dd:d9:dd:c25:c25a:d00a:e191/1282c19:dd:d9:dd:c25:c25a:d00a:e191
1472c19:dd:d9:dd:c25:c25a:d00a:e192/1282c19:dd:d9:dd:c25:c25a:d00a:e192
1482c19:dd:d9:dd:c25:c25a:d00a:e193/1282c19:dd:d9:dd:c25:c25a:d00a:e193
1492c19:dd:d9:dd:c25:c25a:d00a:e194/1282c19:dd:d9:dd:c25:c25a:d00a:e194
1502c19:dd:d9:dd:c25:c25a:d00a:e195/1282c19:dd:d9:dd:c25:c25a:d00a:e195
1512c19:dd:d9:dd:c25:c25a:d00a:e196/1282c19:dd:d9:dd:c25:c25a:d00a:e196
1522c19:dd:d9:dd:c25:c25a:d00a:e197/1282c19:dd:d9:dd:c25:c25a:d00a:e197
1532c19:dd:d9:dd:c25:c25a:d00a:e198/1282c19:dd:d9:dd:c25:c25a:d00a:e198
1542c19:dd:d9:dd:c25:c25a:d00a:e199/1282c19:dd:d9:dd:c25:c25a:d00a:e199
1552c19:dd:d9:dd:c25:c25a:d00a:e19a/1282c19:dd:d9:dd:c25:c25a:d00a:e19a
1562c19:dd:d9:dd:c25:c25a:d00a:e19b/1282c19:dd:d9:dd:c25:c25a:d00a:e19b
1572c19:dd:d9:dd:c25:c25a:d00a:e19c/1282c19:dd:d9:dd:c25:c25a:d00a:e19c
1582c19:dd:d9:dd:c25:c25a:d00a:e19d/1282c19:dd:d9:dd:c25:c25a:d00a:e19d
1592c19:dd:d9:dd:c25:c25a:d00a:e19e/1282c19:dd:d9:dd:c25:c25a:d00a:e19e
1602c19:dd:d9:dd:c25:c25a:d00a:e19f/1282c19:dd:d9:dd:c25:c25a:d00a:e19f
1612c19:dd:d9:dd:c25:c25a:d00a:e1a0/1282c19:dd:d9:dd:c25:c25a:d00a:e1a0
1622c19:dd:d9:dd:c25:c25a:d00a:e1a1/1282c19:dd:d9:dd:c25:c25a:d00a:e1a1
1632c19:dd:d9:dd:c25:c25a:d00a:e1a2/1282c19:dd:d9:dd:c25:c25a:d00a:e1a2
1642c19:dd:d9:dd:c25:c25a:d00a:e1a3/1282c19:dd:d9:dd:c25:c25a:d00a:e1a3
1652c19:dd:d9:dd:c25:c25a:d00a:e1a4/1282c19:dd:d9:dd:c25:c25a:d00a:e1a4
1662c19:dd:d9:dd:c25:c25a:d00a:e1a5/1282c19:dd:d9:dd:c25:c25a:d00a:e1a5
1672c19:dd:d9:dd:c25:c25a:d00a:e1a6/1282c19:dd:d9:dd:c25:c25a:d00a:e1a6
1682c19:dd:d9:dd:c25:c25a:d00a:e1a7/1282c19:dd:d9:dd:c25:c25a:d00a:e1a7
1692c19:dd:d9:dd:c25:c25a:d00a:e1a8/1282c19:dd:d9:dd:c25:c25a:d00a:e1a8
1702c19:dd:d9:dd:c25:c25a:d00a:e1a9/1282c19:dd:d9:dd:c25:c25a:d00a:e1a9
1712c19:dd:d9:dd:c25:c25a:d00a:e1aa/1282c19:dd:d9:dd:c25:c25a:d00a:e1aa
1722c19:dd:d9:dd:c25:c25a:d00a:e1ab/1282c19:dd:d9:dd:c25:c25a:d00a:e1ab
1732c19:dd:d9:dd:c25:c25a:d00a:e1ac/1282c19:dd:d9:dd:c25:c25a:d00a:e1ac
1742c19:dd:d9:dd:c25:c25a:d00a:e1ad/1282c19:dd:d9:dd:c25:c25a:d00a:e1ad
1752c19:dd:d9:dd:c25:c25a:d00a:e1ae/1282c19:dd:d9:dd:c25:c25a:d00a:e1ae
1762c19:dd:d9:dd:c25:c25a:d00a:e1af/1282c19:dd:d9:dd:c25:c25a:d00a:e1af
1772c19:dd:d9:dd:c25:c25a:d00a:e1b0/1282c19:dd:d9:dd:c25:c25a:d00a:e1b0
1782c19:dd:d9:dd:c25:c25a:d00a:e1b1/1282c19:dd:d9:dd:c25:c25a:d00a:e1b1
1792c19:dd:d9:dd:c25:c25a:d00a:e1b2/1282c19:dd:d9:dd:c25:c25a:d00a:e1b2
1802c19:dd:d9:dd:c25:c25a:d00a:e1b3/1282c19:dd:d9:dd:c25:c25a:d00a:e1b3
1812c19:dd:d9:dd:c25:c25a:d00a:e1b4/1282c19:dd:d9:dd:c25:c25a:d00a:e1b4
1822c19:dd:d9:dd:c25:c25a:d00a:e1b5/1282c19:dd:d9:dd:c25:c25a:d00a:e1b5
1832c19:dd:d9:dd:c25:c25a:d00a:e1b6/1282c19:dd:d9:dd:c25:c25a:d00a:e1b6
1842c19:dd:d9:dd:c25:c25a:d00a:e1b7/1282c19:dd:d9:dd:c25:c25a:d00a:e1b7
1852c19:dd:d9:dd:c25:c25a:d00a:e1b8/1282c19:dd:d9:dd:c25:c25a:d00a:e1b8
1862c19:dd:d9:dd:c25:c25a:d00a:e1b9/1282c19:dd:d9:dd:c25:c25a:d00a:e1b9
1872c19:dd:d9:dd:c25:c25a:d00a:e1ba/1282c19:dd:d9:dd:c25:c25a:d00a:e1ba
1882c19:dd:d9:dd:c25:c25a:d00a:e1bb/1282c19:dd:d9:dd:c25:c25a:d00a:e1bb
1892c19:dd:d9:dd:c25:c25a:d00a:e1bc/1282c19:dd:d9:dd:c25:c25a:d00a:e1bc
1902c19:dd:d9:dd:c25:c25a:d00a:e1bd/1282c19:dd:d9:dd:c25:c25a:d00a:e1bd
1912c19:dd:d9:dd:c25:c25a:d00a:e1be/1282c19:dd:d9:dd:c25:c25a:d00a:e1be
1922c19:dd:d9:dd:c25:c25a:d00a:e1bf/1282c19:dd:d9:dd:c25:c25a:d00a:e1bf
1932c19:dd:d9:dd:c25:c25a:d00a:e1c0/1282c19:dd:d9:dd:c25:c25a:d00a:e1c0
1942c19:dd:d9:dd:c25:c25a:d00a:e1c1/1282c19:dd:d9:dd:c25:c25a:d00a:e1c1
1952c19:dd:d9:dd:c25:c25a:d00a:e1c2/1282c19:dd:d9:dd:c25:c25a:d00a:e1c2
1962c19:dd:d9:dd:c25:c25a:d00a:e1c3/1282c19:dd:d9:dd:c25:c25a:d00a:e1c3
1972c19:dd:d9:dd:c25:c25a:d00a:e1c4/1282c19:dd:d9:dd:c25:c25a:d00a:e1c4
1982c19:dd:d9:dd:c25:c25a:d00a:e1c5/1282c19:dd:d9:dd:c25:c25a:d00a:e1c5
1992c19:dd:d9:dd:c25:c25a:d00a:e1c6/1282c19:dd:d9:dd:c25:c25a:d00a:e1c6
2002c19:dd:d9:dd:c25:c25a:d00a:e1c7/1282c19:dd:d9:dd:c25:c25a:d00a:e1c7
2012c19:dd:d9:dd:c25:c25a:d00a:e1c8/1282c19:dd:d9:dd:c25:c25a:d00a:e1c8
2022c19:dd:d9:dd:c25:c25a:d00a:e1c9/1282c19:dd:d9:dd:c25:c25a:d00a:e1c9
2032c19:dd:d9:dd:c25:c25a:d00a:e1ca/1282c19:dd:d9:dd:c25:c25a:d00a:e1ca
2042c19:dd:d9:dd:c25:c25a:d00a:e1cb/1282c19:dd:d9:dd:c25:c25a:d00a:e1cb
2052c19:dd:d9:dd:c25:c25a:d00a:e1cc/1282c19:dd:d9:dd:c25:c25a:d00a:e1cc
2062c19:dd:d9:dd:c25:c25a:d00a:e1cd/1282c19:dd:d9:dd:c25:c25a:d00a:e1cd
2072c19:dd:d9:dd:c25:c25a:d00a:e1ce/1282c19:dd:d9:dd:c25:c25a:d00a:e1ce
2082c19:dd:d9:dd:c25:c25a:d00a:e1cf/1282c19:dd:d9:dd:c25:c25a:d00a:e1cf
2092c19:dd:d9:dd:c25:c25a:d00a:e1d0/1282c19:dd:d9:dd:c25:c25a:d00a:e1d0
2102c19:dd:d9:dd:c25:c25a:d00a:e1d1/1282c19:dd:d9:dd:c25:c25a:d00a:e1d1
2112c19:dd:d9:dd:c25:c25a:d00a:e1d2/1282c19:dd:d9:dd:c25:c25a:d00a:e1d2
2122c19:dd:d9:dd:c25:c25a:d00a:e1d3/1282c19:dd:d9:dd:c25:c25a:d00a:e1d3
2132c19:dd:d9:dd:c25:c25a:d00a:e1d4/1282c19:dd:d9:dd:c25:c25a:d00a:e1d4
2142c19:dd:d9:dd:c25:c25a:d00a:e1d5/1282c19:dd:d9:dd:c25:c25a:d00a:e1d5
2152c19:dd:d9:dd:c25:c25a:d00a:e1d6/1282c19:dd:d9:dd:c25:c25a:d00a:e1d6
2162c19:dd:d9:dd:c25:c25a:d00a:e1d7/1282c19:dd:d9:dd:c25:c25a:d00a:e1d7
2172c19:dd:d9:dd:c25:c25a:d00a:e1d8/1282c19:dd:d9:dd:c25:c25a:d00a:e1d8
2182c19:dd:d9:dd:c25:c25a:d00a:e1d9/1282c19:dd:d9:dd:c25:c25a:d00a:e1d9
2192c19:dd:d9:dd:c25:c25a:d00a:e1da/1282c19:dd:d9:dd:c25:c25a:d00a:e1da
2202c19:dd:d9:dd:c25:c25a:d00a:e1db/1282c19:dd:d9:dd:c25:c25a:d00a:e1db
2212c19:dd:d9:dd:c25:c25a:d00a:e1dc/1282c19:dd:d9:dd:c25:c25a:d00a:e1dc
2222c19:dd:d9:dd:c25:c25a:d00a:e1dd/1282c19:dd:d9:dd:c25:c25a:d00a:e1dd
2232c19:dd:d9:dd:c25:c25a:d00a:e1de/1282c19:dd:d9:dd:c25:c25a:d00a:e1de
2242c19:dd:d9:dd:c25:c25a:d00a:e1df/1282c19:dd:d9:dd:c25:c25a:d00a:e1df
2252c19:dd:d9:dd:c25:c25a:d00a:e1e0/1282c19:dd:d9:dd:c25:c25a:d00a:e1e0
2262c19:dd:d9:dd:c25:c25a:d00a:e1e1/1282c19:dd:d9:dd:c25:c25a:d00a:e1e1
2272c19:dd:d9:dd:c25:c25a:d00a:e1e2/1282c19:dd:d9:dd:c25:c25a:d00a:e1e2
2282c19:dd:d9:dd:c25:c25a:d00a:e1e3/1282c19:dd:d9:dd:c25:c25a:d00a:e1e3
2292c19:dd:d9:dd:c25:c25a:d00a:e1e4/1282c19:dd:d9:dd:c25:c25a:d00a:e1e4
2302c19:dd:d9:dd:c25:c25a:d00a:e1e5/1282c19:dd:d9:dd:c25:c25a:d00a:e1e5
2312c19:dd:d9:dd:c25:c25a:d00a:e1e6/1282c19:dd:d9:dd:c25:c25a:d00a:e1e6
2322c19:dd:d9:dd:c25:c25a:d00a:e1e7/1282c19:dd:d9:dd:c25:c25a:d00a:e1e7
2332c19:dd:d9:dd:c25:c25a:d00a:e1e8/1282c19:dd:d9:dd:c25:c25a:d00a:e1e8
2342c19:dd:d9:dd:c25:c25a:d00a:e1e9/1282c19:dd:d9:dd:c25:c25a:d00a:e1e9
2352c19:dd:d9:dd:c25:c25a:d00a:e1ea/1282c19:dd:d9:dd:c25:c25a:d00a:e1ea
2362c19:dd:d9:dd:c25:c25a:d00a:e1eb/1282c19:dd:d9:dd:c25:c25a:d00a:e1eb
2372c19:dd:d9:dd:c25:c25a:d00a:e1ec/1282c19:dd:d9:dd:c25:c25a:d00a:e1ec
2382c19:dd:d9:dd:c25:c25a:d00a:e1ed/1282c19:dd:d9:dd:c25:c25a:d00a:e1ed
2392c19:dd:d9:dd:c25:c25a:d00a:e1ee/1282c19:dd:d9:dd:c25:c25a:d00a:e1ee
2402c19:dd:d9:dd:c25:c25a:d00a:e1ef/1282c19:dd:d9:dd:c25:c25a:d00a:e1ef
2412c19:dd:d9:dd:c25:c25a:d00a:e1f0/1282c19:dd:d9:dd:c25:c25a:d00a:e1f0
2422c19:dd:d9:dd:c25:c25a:d00a:e1f1/1282c19:dd:d9:dd:c25:c25a:d00a:e1f1
2432c19:dd:d9:dd:c25:c25a:d00a:e1f2/1282c19:dd:d9:dd:c25:c25a:d00a:e1f2
2442c19:dd:d9:dd:c25:c25a:d00a:e1f3/1282c19:dd:d9:dd:c25:c25a:d00a:e1f3
2452c19:dd:d9:dd:c25:c25a:d00a:e1f4/1282c19:dd:d9:dd:c25:c25a:d00a:e1f4
2462c19:dd:d9:dd:c25:c25a:d00a:e1f5/1282c19:dd:d9:dd:c25:c25a:d00a:e1f5
2472c19:dd:d9:dd:c25:c25a:d00a:e1f6/1282c19:dd:d9:dd:c25:c25a:d00a:e1f6
2482c19:dd:d9:dd:c25:c25a:d00a:e1f7/1282c19:dd:d9:dd:c25:c25a:d00a:e1f7
2492c19:dd:d9:dd:c25:c25a:d00a:e1f8/1282c19:dd:d9:dd:c25:c25a:d00a:e1f8
2502c19:dd:d9:dd:c25:c25a:d00a:e1f9/1282c19:dd:d9:dd:c25:c25a:d00a:e1f9
2512c19:dd:d9:dd:c25:c25a:d00a:e1fa/1282c19:dd:d9:dd:c25:c25a:d00a:e1fa
2522c19:dd:d9:dd:c25:c25a:d00a:e1fb/1282c19:dd:d9:dd:c25:c25a:d00a:e1fb
2532c19:dd:d9:dd:c25:c25a:d00a:e1fc/1282c19:dd:d9:dd:c25:c25a:d00a:e1fc
2542c19:dd:d9:dd:c25:c25a:d00a:e1fd/1282c19:dd:d9:dd:c25:c25a:d00a:e1fd
2552c19:dd:d9:dd:c25:c25a:d00a:e1fe/1282c19:dd:d9:dd:c25:c25a:d00a:e1fe
2562c19:dd:d9:dd:c25:c25a:d00a:e1ff/1282c19:dd:d9:dd:c25:c25a:d00a: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.