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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:c25:94de:9100/120
First address
2c19:dd:d9:dd:c25:c25:94de:9100
Last address
2c19:dd:d9:dd:c25:c25:94de:91ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:9100
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
1.9.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:94de:9100/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:9100/1282c19:dd:d9:dd:c25:c25:94de:9100
22c19:dd:d9:dd:c25:c25:94de:9101/1282c19:dd:d9:dd:c25:c25:94de:9101
32c19:dd:d9:dd:c25:c25:94de:9102/1282c19:dd:d9:dd:c25:c25:94de:9102
42c19:dd:d9:dd:c25:c25:94de:9103/1282c19:dd:d9:dd:c25:c25:94de:9103
52c19:dd:d9:dd:c25:c25:94de:9104/1282c19:dd:d9:dd:c25:c25:94de:9104
62c19:dd:d9:dd:c25:c25:94de:9105/1282c19:dd:d9:dd:c25:c25:94de:9105
72c19:dd:d9:dd:c25:c25:94de:9106/1282c19:dd:d9:dd:c25:c25:94de:9106
82c19:dd:d9:dd:c25:c25:94de:9107/1282c19:dd:d9:dd:c25:c25:94de:9107
92c19:dd:d9:dd:c25:c25:94de:9108/1282c19:dd:d9:dd:c25:c25:94de:9108
102c19:dd:d9:dd:c25:c25:94de:9109/1282c19:dd:d9:dd:c25:c25:94de:9109
112c19:dd:d9:dd:c25:c25:94de:910a/1282c19:dd:d9:dd:c25:c25:94de:910a
122c19:dd:d9:dd:c25:c25:94de:910b/1282c19:dd:d9:dd:c25:c25:94de:910b
132c19:dd:d9:dd:c25:c25:94de:910c/1282c19:dd:d9:dd:c25:c25:94de:910c
142c19:dd:d9:dd:c25:c25:94de:910d/1282c19:dd:d9:dd:c25:c25:94de:910d
152c19:dd:d9:dd:c25:c25:94de:910e/1282c19:dd:d9:dd:c25:c25:94de:910e
162c19:dd:d9:dd:c25:c25:94de:910f/1282c19:dd:d9:dd:c25:c25:94de:910f
172c19:dd:d9:dd:c25:c25:94de:9110/1282c19:dd:d9:dd:c25:c25:94de:9110
182c19:dd:d9:dd:c25:c25:94de:9111/1282c19:dd:d9:dd:c25:c25:94de:9111
192c19:dd:d9:dd:c25:c25:94de:9112/1282c19:dd:d9:dd:c25:c25:94de:9112
202c19:dd:d9:dd:c25:c25:94de:9113/1282c19:dd:d9:dd:c25:c25:94de:9113
212c19:dd:d9:dd:c25:c25:94de:9114/1282c19:dd:d9:dd:c25:c25:94de:9114
222c19:dd:d9:dd:c25:c25:94de:9115/1282c19:dd:d9:dd:c25:c25:94de:9115
232c19:dd:d9:dd:c25:c25:94de:9116/1282c19:dd:d9:dd:c25:c25:94de:9116
242c19:dd:d9:dd:c25:c25:94de:9117/1282c19:dd:d9:dd:c25:c25:94de:9117
252c19:dd:d9:dd:c25:c25:94de:9118/1282c19:dd:d9:dd:c25:c25:94de:9118
262c19:dd:d9:dd:c25:c25:94de:9119/1282c19:dd:d9:dd:c25:c25:94de:9119
272c19:dd:d9:dd:c25:c25:94de:911a/1282c19:dd:d9:dd:c25:c25:94de:911a
282c19:dd:d9:dd:c25:c25:94de:911b/1282c19:dd:d9:dd:c25:c25:94de:911b
292c19:dd:d9:dd:c25:c25:94de:911c/1282c19:dd:d9:dd:c25:c25:94de:911c
302c19:dd:d9:dd:c25:c25:94de:911d/1282c19:dd:d9:dd:c25:c25:94de:911d
312c19:dd:d9:dd:c25:c25:94de:911e/1282c19:dd:d9:dd:c25:c25:94de:911e
322c19:dd:d9:dd:c25:c25:94de:911f/1282c19:dd:d9:dd:c25:c25:94de:911f
332c19:dd:d9:dd:c25:c25:94de:9120/1282c19:dd:d9:dd:c25:c25:94de:9120
342c19:dd:d9:dd:c25:c25:94de:9121/1282c19:dd:d9:dd:c25:c25:94de:9121
352c19:dd:d9:dd:c25:c25:94de:9122/1282c19:dd:d9:dd:c25:c25:94de:9122
362c19:dd:d9:dd:c25:c25:94de:9123/1282c19:dd:d9:dd:c25:c25:94de:9123
372c19:dd:d9:dd:c25:c25:94de:9124/1282c19:dd:d9:dd:c25:c25:94de:9124
382c19:dd:d9:dd:c25:c25:94de:9125/1282c19:dd:d9:dd:c25:c25:94de:9125
392c19:dd:d9:dd:c25:c25:94de:9126/1282c19:dd:d9:dd:c25:c25:94de:9126
402c19:dd:d9:dd:c25:c25:94de:9127/1282c19:dd:d9:dd:c25:c25:94de:9127
412c19:dd:d9:dd:c25:c25:94de:9128/1282c19:dd:d9:dd:c25:c25:94de:9128
422c19:dd:d9:dd:c25:c25:94de:9129/1282c19:dd:d9:dd:c25:c25:94de:9129
432c19:dd:d9:dd:c25:c25:94de:912a/1282c19:dd:d9:dd:c25:c25:94de:912a
442c19:dd:d9:dd:c25:c25:94de:912b/1282c19:dd:d9:dd:c25:c25:94de:912b
452c19:dd:d9:dd:c25:c25:94de:912c/1282c19:dd:d9:dd:c25:c25:94de:912c
462c19:dd:d9:dd:c25:c25:94de:912d/1282c19:dd:d9:dd:c25:c25:94de:912d
472c19:dd:d9:dd:c25:c25:94de:912e/1282c19:dd:d9:dd:c25:c25:94de:912e
482c19:dd:d9:dd:c25:c25:94de:912f/1282c19:dd:d9:dd:c25:c25:94de:912f
492c19:dd:d9:dd:c25:c25:94de:9130/1282c19:dd:d9:dd:c25:c25:94de:9130
502c19:dd:d9:dd:c25:c25:94de:9131/1282c19:dd:d9:dd:c25:c25:94de:9131
512c19:dd:d9:dd:c25:c25:94de:9132/1282c19:dd:d9:dd:c25:c25:94de:9132
522c19:dd:d9:dd:c25:c25:94de:9133/1282c19:dd:d9:dd:c25:c25:94de:9133
532c19:dd:d9:dd:c25:c25:94de:9134/1282c19:dd:d9:dd:c25:c25:94de:9134
542c19:dd:d9:dd:c25:c25:94de:9135/1282c19:dd:d9:dd:c25:c25:94de:9135
552c19:dd:d9:dd:c25:c25:94de:9136/1282c19:dd:d9:dd:c25:c25:94de:9136
562c19:dd:d9:dd:c25:c25:94de:9137/1282c19:dd:d9:dd:c25:c25:94de:9137
572c19:dd:d9:dd:c25:c25:94de:9138/1282c19:dd:d9:dd:c25:c25:94de:9138
582c19:dd:d9:dd:c25:c25:94de:9139/1282c19:dd:d9:dd:c25:c25:94de:9139
592c19:dd:d9:dd:c25:c25:94de:913a/1282c19:dd:d9:dd:c25:c25:94de:913a
602c19:dd:d9:dd:c25:c25:94de:913b/1282c19:dd:d9:dd:c25:c25:94de:913b
612c19:dd:d9:dd:c25:c25:94de:913c/1282c19:dd:d9:dd:c25:c25:94de:913c
622c19:dd:d9:dd:c25:c25:94de:913d/1282c19:dd:d9:dd:c25:c25:94de:913d
632c19:dd:d9:dd:c25:c25:94de:913e/1282c19:dd:d9:dd:c25:c25:94de:913e
642c19:dd:d9:dd:c25:c25:94de:913f/1282c19:dd:d9:dd:c25:c25:94de:913f
652c19:dd:d9:dd:c25:c25:94de:9140/1282c19:dd:d9:dd:c25:c25:94de:9140
662c19:dd:d9:dd:c25:c25:94de:9141/1282c19:dd:d9:dd:c25:c25:94de:9141
672c19:dd:d9:dd:c25:c25:94de:9142/1282c19:dd:d9:dd:c25:c25:94de:9142
682c19:dd:d9:dd:c25:c25:94de:9143/1282c19:dd:d9:dd:c25:c25:94de:9143
692c19:dd:d9:dd:c25:c25:94de:9144/1282c19:dd:d9:dd:c25:c25:94de:9144
702c19:dd:d9:dd:c25:c25:94de:9145/1282c19:dd:d9:dd:c25:c25:94de:9145
712c19:dd:d9:dd:c25:c25:94de:9146/1282c19:dd:d9:dd:c25:c25:94de:9146
722c19:dd:d9:dd:c25:c25:94de:9147/1282c19:dd:d9:dd:c25:c25:94de:9147
732c19:dd:d9:dd:c25:c25:94de:9148/1282c19:dd:d9:dd:c25:c25:94de:9148
742c19:dd:d9:dd:c25:c25:94de:9149/1282c19:dd:d9:dd:c25:c25:94de:9149
752c19:dd:d9:dd:c25:c25:94de:914a/1282c19:dd:d9:dd:c25:c25:94de:914a
762c19:dd:d9:dd:c25:c25:94de:914b/1282c19:dd:d9:dd:c25:c25:94de:914b
772c19:dd:d9:dd:c25:c25:94de:914c/1282c19:dd:d9:dd:c25:c25:94de:914c
782c19:dd:d9:dd:c25:c25:94de:914d/1282c19:dd:d9:dd:c25:c25:94de:914d
792c19:dd:d9:dd:c25:c25:94de:914e/1282c19:dd:d9:dd:c25:c25:94de:914e
802c19:dd:d9:dd:c25:c25:94de:914f/1282c19:dd:d9:dd:c25:c25:94de:914f
812c19:dd:d9:dd:c25:c25:94de:9150/1282c19:dd:d9:dd:c25:c25:94de:9150
822c19:dd:d9:dd:c25:c25:94de:9151/1282c19:dd:d9:dd:c25:c25:94de:9151
832c19:dd:d9:dd:c25:c25:94de:9152/1282c19:dd:d9:dd:c25:c25:94de:9152
842c19:dd:d9:dd:c25:c25:94de:9153/1282c19:dd:d9:dd:c25:c25:94de:9153
852c19:dd:d9:dd:c25:c25:94de:9154/1282c19:dd:d9:dd:c25:c25:94de:9154
862c19:dd:d9:dd:c25:c25:94de:9155/1282c19:dd:d9:dd:c25:c25:94de:9155
872c19:dd:d9:dd:c25:c25:94de:9156/1282c19:dd:d9:dd:c25:c25:94de:9156
882c19:dd:d9:dd:c25:c25:94de:9157/1282c19:dd:d9:dd:c25:c25:94de:9157
892c19:dd:d9:dd:c25:c25:94de:9158/1282c19:dd:d9:dd:c25:c25:94de:9158
902c19:dd:d9:dd:c25:c25:94de:9159/1282c19:dd:d9:dd:c25:c25:94de:9159
912c19:dd:d9:dd:c25:c25:94de:915a/1282c19:dd:d9:dd:c25:c25:94de:915a
922c19:dd:d9:dd:c25:c25:94de:915b/1282c19:dd:d9:dd:c25:c25:94de:915b
932c19:dd:d9:dd:c25:c25:94de:915c/1282c19:dd:d9:dd:c25:c25:94de:915c
942c19:dd:d9:dd:c25:c25:94de:915d/1282c19:dd:d9:dd:c25:c25:94de:915d
952c19:dd:d9:dd:c25:c25:94de:915e/1282c19:dd:d9:dd:c25:c25:94de:915e
962c19:dd:d9:dd:c25:c25:94de:915f/1282c19:dd:d9:dd:c25:c25:94de:915f
972c19:dd:d9:dd:c25:c25:94de:9160/1282c19:dd:d9:dd:c25:c25:94de:9160
982c19:dd:d9:dd:c25:c25:94de:9161/1282c19:dd:d9:dd:c25:c25:94de:9161
992c19:dd:d9:dd:c25:c25:94de:9162/1282c19:dd:d9:dd:c25:c25:94de:9162
1002c19:dd:d9:dd:c25:c25:94de:9163/1282c19:dd:d9:dd:c25:c25:94de:9163
1012c19:dd:d9:dd:c25:c25:94de:9164/1282c19:dd:d9:dd:c25:c25:94de:9164
1022c19:dd:d9:dd:c25:c25:94de:9165/1282c19:dd:d9:dd:c25:c25:94de:9165
1032c19:dd:d9:dd:c25:c25:94de:9166/1282c19:dd:d9:dd:c25:c25:94de:9166
1042c19:dd:d9:dd:c25:c25:94de:9167/1282c19:dd:d9:dd:c25:c25:94de:9167
1052c19:dd:d9:dd:c25:c25:94de:9168/1282c19:dd:d9:dd:c25:c25:94de:9168
1062c19:dd:d9:dd:c25:c25:94de:9169/1282c19:dd:d9:dd:c25:c25:94de:9169
1072c19:dd:d9:dd:c25:c25:94de:916a/1282c19:dd:d9:dd:c25:c25:94de:916a
1082c19:dd:d9:dd:c25:c25:94de:916b/1282c19:dd:d9:dd:c25:c25:94de:916b
1092c19:dd:d9:dd:c25:c25:94de:916c/1282c19:dd:d9:dd:c25:c25:94de:916c
1102c19:dd:d9:dd:c25:c25:94de:916d/1282c19:dd:d9:dd:c25:c25:94de:916d
1112c19:dd:d9:dd:c25:c25:94de:916e/1282c19:dd:d9:dd:c25:c25:94de:916e
1122c19:dd:d9:dd:c25:c25:94de:916f/1282c19:dd:d9:dd:c25:c25:94de:916f
1132c19:dd:d9:dd:c25:c25:94de:9170/1282c19:dd:d9:dd:c25:c25:94de:9170
1142c19:dd:d9:dd:c25:c25:94de:9171/1282c19:dd:d9:dd:c25:c25:94de:9171
1152c19:dd:d9:dd:c25:c25:94de:9172/1282c19:dd:d9:dd:c25:c25:94de:9172
1162c19:dd:d9:dd:c25:c25:94de:9173/1282c19:dd:d9:dd:c25:c25:94de:9173
1172c19:dd:d9:dd:c25:c25:94de:9174/1282c19:dd:d9:dd:c25:c25:94de:9174
1182c19:dd:d9:dd:c25:c25:94de:9175/1282c19:dd:d9:dd:c25:c25:94de:9175
1192c19:dd:d9:dd:c25:c25:94de:9176/1282c19:dd:d9:dd:c25:c25:94de:9176
1202c19:dd:d9:dd:c25:c25:94de:9177/1282c19:dd:d9:dd:c25:c25:94de:9177
1212c19:dd:d9:dd:c25:c25:94de:9178/1282c19:dd:d9:dd:c25:c25:94de:9178
1222c19:dd:d9:dd:c25:c25:94de:9179/1282c19:dd:d9:dd:c25:c25:94de:9179
1232c19:dd:d9:dd:c25:c25:94de:917a/1282c19:dd:d9:dd:c25:c25:94de:917a
1242c19:dd:d9:dd:c25:c25:94de:917b/1282c19:dd:d9:dd:c25:c25:94de:917b
1252c19:dd:d9:dd:c25:c25:94de:917c/1282c19:dd:d9:dd:c25:c25:94de:917c
1262c19:dd:d9:dd:c25:c25:94de:917d/1282c19:dd:d9:dd:c25:c25:94de:917d
1272c19:dd:d9:dd:c25:c25:94de:917e/1282c19:dd:d9:dd:c25:c25:94de:917e
1282c19:dd:d9:dd:c25:c25:94de:917f/1282c19:dd:d9:dd:c25:c25:94de:917f
1292c19:dd:d9:dd:c25:c25:94de:9180/1282c19:dd:d9:dd:c25:c25:94de:9180
1302c19:dd:d9:dd:c25:c25:94de:9181/1282c19:dd:d9:dd:c25:c25:94de:9181
1312c19:dd:d9:dd:c25:c25:94de:9182/1282c19:dd:d9:dd:c25:c25:94de:9182
1322c19:dd:d9:dd:c25:c25:94de:9183/1282c19:dd:d9:dd:c25:c25:94de:9183
1332c19:dd:d9:dd:c25:c25:94de:9184/1282c19:dd:d9:dd:c25:c25:94de:9184
1342c19:dd:d9:dd:c25:c25:94de:9185/1282c19:dd:d9:dd:c25:c25:94de:9185
1352c19:dd:d9:dd:c25:c25:94de:9186/1282c19:dd:d9:dd:c25:c25:94de:9186
1362c19:dd:d9:dd:c25:c25:94de:9187/1282c19:dd:d9:dd:c25:c25:94de:9187
1372c19:dd:d9:dd:c25:c25:94de:9188/1282c19:dd:d9:dd:c25:c25:94de:9188
1382c19:dd:d9:dd:c25:c25:94de:9189/1282c19:dd:d9:dd:c25:c25:94de:9189
1392c19:dd:d9:dd:c25:c25:94de:918a/1282c19:dd:d9:dd:c25:c25:94de:918a
1402c19:dd:d9:dd:c25:c25:94de:918b/1282c19:dd:d9:dd:c25:c25:94de:918b
1412c19:dd:d9:dd:c25:c25:94de:918c/1282c19:dd:d9:dd:c25:c25:94de:918c
1422c19:dd:d9:dd:c25:c25:94de:918d/1282c19:dd:d9:dd:c25:c25:94de:918d
1432c19:dd:d9:dd:c25:c25:94de:918e/1282c19:dd:d9:dd:c25:c25:94de:918e
1442c19:dd:d9:dd:c25:c25:94de:918f/1282c19:dd:d9:dd:c25:c25:94de:918f
1452c19:dd:d9:dd:c25:c25:94de:9190/1282c19:dd:d9:dd:c25:c25:94de:9190
1462c19:dd:d9:dd:c25:c25:94de:9191/1282c19:dd:d9:dd:c25:c25:94de:9191
1472c19:dd:d9:dd:c25:c25:94de:9192/1282c19:dd:d9:dd:c25:c25:94de:9192
1482c19:dd:d9:dd:c25:c25:94de:9193/1282c19:dd:d9:dd:c25:c25:94de:9193
1492c19:dd:d9:dd:c25:c25:94de:9194/1282c19:dd:d9:dd:c25:c25:94de:9194
1502c19:dd:d9:dd:c25:c25:94de:9195/1282c19:dd:d9:dd:c25:c25:94de:9195
1512c19:dd:d9:dd:c25:c25:94de:9196/1282c19:dd:d9:dd:c25:c25:94de:9196
1522c19:dd:d9:dd:c25:c25:94de:9197/1282c19:dd:d9:dd:c25:c25:94de:9197
1532c19:dd:d9:dd:c25:c25:94de:9198/1282c19:dd:d9:dd:c25:c25:94de:9198
1542c19:dd:d9:dd:c25:c25:94de:9199/1282c19:dd:d9:dd:c25:c25:94de:9199
1552c19:dd:d9:dd:c25:c25:94de:919a/1282c19:dd:d9:dd:c25:c25:94de:919a
1562c19:dd:d9:dd:c25:c25:94de:919b/1282c19:dd:d9:dd:c25:c25:94de:919b
1572c19:dd:d9:dd:c25:c25:94de:919c/1282c19:dd:d9:dd:c25:c25:94de:919c
1582c19:dd:d9:dd:c25:c25:94de:919d/1282c19:dd:d9:dd:c25:c25:94de:919d
1592c19:dd:d9:dd:c25:c25:94de:919e/1282c19:dd:d9:dd:c25:c25:94de:919e
1602c19:dd:d9:dd:c25:c25:94de:919f/1282c19:dd:d9:dd:c25:c25:94de:919f
1612c19:dd:d9:dd:c25:c25:94de:91a0/1282c19:dd:d9:dd:c25:c25:94de:91a0
1622c19:dd:d9:dd:c25:c25:94de:91a1/1282c19:dd:d9:dd:c25:c25:94de:91a1
1632c19:dd:d9:dd:c25:c25:94de:91a2/1282c19:dd:d9:dd:c25:c25:94de:91a2
1642c19:dd:d9:dd:c25:c25:94de:91a3/1282c19:dd:d9:dd:c25:c25:94de:91a3
1652c19:dd:d9:dd:c25:c25:94de:91a4/1282c19:dd:d9:dd:c25:c25:94de:91a4
1662c19:dd:d9:dd:c25:c25:94de:91a5/1282c19:dd:d9:dd:c25:c25:94de:91a5
1672c19:dd:d9:dd:c25:c25:94de:91a6/1282c19:dd:d9:dd:c25:c25:94de:91a6
1682c19:dd:d9:dd:c25:c25:94de:91a7/1282c19:dd:d9:dd:c25:c25:94de:91a7
1692c19:dd:d9:dd:c25:c25:94de:91a8/1282c19:dd:d9:dd:c25:c25:94de:91a8
1702c19:dd:d9:dd:c25:c25:94de:91a9/1282c19:dd:d9:dd:c25:c25:94de:91a9
1712c19:dd:d9:dd:c25:c25:94de:91aa/1282c19:dd:d9:dd:c25:c25:94de:91aa
1722c19:dd:d9:dd:c25:c25:94de:91ab/1282c19:dd:d9:dd:c25:c25:94de:91ab
1732c19:dd:d9:dd:c25:c25:94de:91ac/1282c19:dd:d9:dd:c25:c25:94de:91ac
1742c19:dd:d9:dd:c25:c25:94de:91ad/1282c19:dd:d9:dd:c25:c25:94de:91ad
1752c19:dd:d9:dd:c25:c25:94de:91ae/1282c19:dd:d9:dd:c25:c25:94de:91ae
1762c19:dd:d9:dd:c25:c25:94de:91af/1282c19:dd:d9:dd:c25:c25:94de:91af
1772c19:dd:d9:dd:c25:c25:94de:91b0/1282c19:dd:d9:dd:c25:c25:94de:91b0
1782c19:dd:d9:dd:c25:c25:94de:91b1/1282c19:dd:d9:dd:c25:c25:94de:91b1
1792c19:dd:d9:dd:c25:c25:94de:91b2/1282c19:dd:d9:dd:c25:c25:94de:91b2
1802c19:dd:d9:dd:c25:c25:94de:91b3/1282c19:dd:d9:dd:c25:c25:94de:91b3
1812c19:dd:d9:dd:c25:c25:94de:91b4/1282c19:dd:d9:dd:c25:c25:94de:91b4
1822c19:dd:d9:dd:c25:c25:94de:91b5/1282c19:dd:d9:dd:c25:c25:94de:91b5
1832c19:dd:d9:dd:c25:c25:94de:91b6/1282c19:dd:d9:dd:c25:c25:94de:91b6
1842c19:dd:d9:dd:c25:c25:94de:91b7/1282c19:dd:d9:dd:c25:c25:94de:91b7
1852c19:dd:d9:dd:c25:c25:94de:91b8/1282c19:dd:d9:dd:c25:c25:94de:91b8
1862c19:dd:d9:dd:c25:c25:94de:91b9/1282c19:dd:d9:dd:c25:c25:94de:91b9
1872c19:dd:d9:dd:c25:c25:94de:91ba/1282c19:dd:d9:dd:c25:c25:94de:91ba
1882c19:dd:d9:dd:c25:c25:94de:91bb/1282c19:dd:d9:dd:c25:c25:94de:91bb
1892c19:dd:d9:dd:c25:c25:94de:91bc/1282c19:dd:d9:dd:c25:c25:94de:91bc
1902c19:dd:d9:dd:c25:c25:94de:91bd/1282c19:dd:d9:dd:c25:c25:94de:91bd
1912c19:dd:d9:dd:c25:c25:94de:91be/1282c19:dd:d9:dd:c25:c25:94de:91be
1922c19:dd:d9:dd:c25:c25:94de:91bf/1282c19:dd:d9:dd:c25:c25:94de:91bf
1932c19:dd:d9:dd:c25:c25:94de:91c0/1282c19:dd:d9:dd:c25:c25:94de:91c0
1942c19:dd:d9:dd:c25:c25:94de:91c1/1282c19:dd:d9:dd:c25:c25:94de:91c1
1952c19:dd:d9:dd:c25:c25:94de:91c2/1282c19:dd:d9:dd:c25:c25:94de:91c2
1962c19:dd:d9:dd:c25:c25:94de:91c3/1282c19:dd:d9:dd:c25:c25:94de:91c3
1972c19:dd:d9:dd:c25:c25:94de:91c4/1282c19:dd:d9:dd:c25:c25:94de:91c4
1982c19:dd:d9:dd:c25:c25:94de:91c5/1282c19:dd:d9:dd:c25:c25:94de:91c5
1992c19:dd:d9:dd:c25:c25:94de:91c6/1282c19:dd:d9:dd:c25:c25:94de:91c6
2002c19:dd:d9:dd:c25:c25:94de:91c7/1282c19:dd:d9:dd:c25:c25:94de:91c7
2012c19:dd:d9:dd:c25:c25:94de:91c8/1282c19:dd:d9:dd:c25:c25:94de:91c8
2022c19:dd:d9:dd:c25:c25:94de:91c9/1282c19:dd:d9:dd:c25:c25:94de:91c9
2032c19:dd:d9:dd:c25:c25:94de:91ca/1282c19:dd:d9:dd:c25:c25:94de:91ca
2042c19:dd:d9:dd:c25:c25:94de:91cb/1282c19:dd:d9:dd:c25:c25:94de:91cb
2052c19:dd:d9:dd:c25:c25:94de:91cc/1282c19:dd:d9:dd:c25:c25:94de:91cc
2062c19:dd:d9:dd:c25:c25:94de:91cd/1282c19:dd:d9:dd:c25:c25:94de:91cd
2072c19:dd:d9:dd:c25:c25:94de:91ce/1282c19:dd:d9:dd:c25:c25:94de:91ce
2082c19:dd:d9:dd:c25:c25:94de:91cf/1282c19:dd:d9:dd:c25:c25:94de:91cf
2092c19:dd:d9:dd:c25:c25:94de:91d0/1282c19:dd:d9:dd:c25:c25:94de:91d0
2102c19:dd:d9:dd:c25:c25:94de:91d1/1282c19:dd:d9:dd:c25:c25:94de:91d1
2112c19:dd:d9:dd:c25:c25:94de:91d2/1282c19:dd:d9:dd:c25:c25:94de:91d2
2122c19:dd:d9:dd:c25:c25:94de:91d3/1282c19:dd:d9:dd:c25:c25:94de:91d3
2132c19:dd:d9:dd:c25:c25:94de:91d4/1282c19:dd:d9:dd:c25:c25:94de:91d4
2142c19:dd:d9:dd:c25:c25:94de:91d5/1282c19:dd:d9:dd:c25:c25:94de:91d5
2152c19:dd:d9:dd:c25:c25:94de:91d6/1282c19:dd:d9:dd:c25:c25:94de:91d6
2162c19:dd:d9:dd:c25:c25:94de:91d7/1282c19:dd:d9:dd:c25:c25:94de:91d7
2172c19:dd:d9:dd:c25:c25:94de:91d8/1282c19:dd:d9:dd:c25:c25:94de:91d8
2182c19:dd:d9:dd:c25:c25:94de:91d9/1282c19:dd:d9:dd:c25:c25:94de:91d9
2192c19:dd:d9:dd:c25:c25:94de:91da/1282c19:dd:d9:dd:c25:c25:94de:91da
2202c19:dd:d9:dd:c25:c25:94de:91db/1282c19:dd:d9:dd:c25:c25:94de:91db
2212c19:dd:d9:dd:c25:c25:94de:91dc/1282c19:dd:d9:dd:c25:c25:94de:91dc
2222c19:dd:d9:dd:c25:c25:94de:91dd/1282c19:dd:d9:dd:c25:c25:94de:91dd
2232c19:dd:d9:dd:c25:c25:94de:91de/1282c19:dd:d9:dd:c25:c25:94de:91de
2242c19:dd:d9:dd:c25:c25:94de:91df/1282c19:dd:d9:dd:c25:c25:94de:91df
2252c19:dd:d9:dd:c25:c25:94de:91e0/1282c19:dd:d9:dd:c25:c25:94de:91e0
2262c19:dd:d9:dd:c25:c25:94de:91e1/1282c19:dd:d9:dd:c25:c25:94de:91e1
2272c19:dd:d9:dd:c25:c25:94de:91e2/1282c19:dd:d9:dd:c25:c25:94de:91e2
2282c19:dd:d9:dd:c25:c25:94de:91e3/1282c19:dd:d9:dd:c25:c25:94de:91e3
2292c19:dd:d9:dd:c25:c25:94de:91e4/1282c19:dd:d9:dd:c25:c25:94de:91e4
2302c19:dd:d9:dd:c25:c25:94de:91e5/1282c19:dd:d9:dd:c25:c25:94de:91e5
2312c19:dd:d9:dd:c25:c25:94de:91e6/1282c19:dd:d9:dd:c25:c25:94de:91e6
2322c19:dd:d9:dd:c25:c25:94de:91e7/1282c19:dd:d9:dd:c25:c25:94de:91e7
2332c19:dd:d9:dd:c25:c25:94de:91e8/1282c19:dd:d9:dd:c25:c25:94de:91e8
2342c19:dd:d9:dd:c25:c25:94de:91e9/1282c19:dd:d9:dd:c25:c25:94de:91e9
2352c19:dd:d9:dd:c25:c25:94de:91ea/1282c19:dd:d9:dd:c25:c25:94de:91ea
2362c19:dd:d9:dd:c25:c25:94de:91eb/1282c19:dd:d9:dd:c25:c25:94de:91eb
2372c19:dd:d9:dd:c25:c25:94de:91ec/1282c19:dd:d9:dd:c25:c25:94de:91ec
2382c19:dd:d9:dd:c25:c25:94de:91ed/1282c19:dd:d9:dd:c25:c25:94de:91ed
2392c19:dd:d9:dd:c25:c25:94de:91ee/1282c19:dd:d9:dd:c25:c25:94de:91ee
2402c19:dd:d9:dd:c25:c25:94de:91ef/1282c19:dd:d9:dd:c25:c25:94de:91ef
2412c19:dd:d9:dd:c25:c25:94de:91f0/1282c19:dd:d9:dd:c25:c25:94de:91f0
2422c19:dd:d9:dd:c25:c25:94de:91f1/1282c19:dd:d9:dd:c25:c25:94de:91f1
2432c19:dd:d9:dd:c25:c25:94de:91f2/1282c19:dd:d9:dd:c25:c25:94de:91f2
2442c19:dd:d9:dd:c25:c25:94de:91f3/1282c19:dd:d9:dd:c25:c25:94de:91f3
2452c19:dd:d9:dd:c25:c25:94de:91f4/1282c19:dd:d9:dd:c25:c25:94de:91f4
2462c19:dd:d9:dd:c25:c25:94de:91f5/1282c19:dd:d9:dd:c25:c25:94de:91f5
2472c19:dd:d9:dd:c25:c25:94de:91f6/1282c19:dd:d9:dd:c25:c25:94de:91f6
2482c19:dd:d9:dd:c25:c25:94de:91f7/1282c19:dd:d9:dd:c25:c25:94de:91f7
2492c19:dd:d9:dd:c25:c25:94de:91f8/1282c19:dd:d9:dd:c25:c25:94de:91f8
2502c19:dd:d9:dd:c25:c25:94de:91f9/1282c19:dd:d9:dd:c25:c25:94de:91f9
2512c19:dd:d9:dd:c25:c25:94de:91fa/1282c19:dd:d9:dd:c25:c25:94de:91fa
2522c19:dd:d9:dd:c25:c25:94de:91fb/1282c19:dd:d9:dd:c25:c25:94de:91fb
2532c19:dd:d9:dd:c25:c25:94de:91fc/1282c19:dd:d9:dd:c25:c25:94de:91fc
2542c19:dd:d9:dd:c25:c25:94de:91fd/1282c19:dd:d9:dd:c25:c25:94de:91fd
2552c19:dd:d9:dd:c25:c25:94de:91fe/1282c19:dd:d9:dd:c25:c25:94de:91fe
2562c19:dd:d9:dd:c25:c25:94de:91ff/1282c19:dd:d9:dd:c25:c25:94de:91ff

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.