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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:4100/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:4100
Last address
2c19:dd:d9:dd:c25:c25a:d00a:41ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:4100
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
1.4.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:4100/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:4100/1282c19:dd:d9:dd:c25:c25a:d00a:4100
22c19:dd:d9:dd:c25:c25a:d00a:4101/1282c19:dd:d9:dd:c25:c25a:d00a:4101
32c19:dd:d9:dd:c25:c25a:d00a:4102/1282c19:dd:d9:dd:c25:c25a:d00a:4102
42c19:dd:d9:dd:c25:c25a:d00a:4103/1282c19:dd:d9:dd:c25:c25a:d00a:4103
52c19:dd:d9:dd:c25:c25a:d00a:4104/1282c19:dd:d9:dd:c25:c25a:d00a:4104
62c19:dd:d9:dd:c25:c25a:d00a:4105/1282c19:dd:d9:dd:c25:c25a:d00a:4105
72c19:dd:d9:dd:c25:c25a:d00a:4106/1282c19:dd:d9:dd:c25:c25a:d00a:4106
82c19:dd:d9:dd:c25:c25a:d00a:4107/1282c19:dd:d9:dd:c25:c25a:d00a:4107
92c19:dd:d9:dd:c25:c25a:d00a:4108/1282c19:dd:d9:dd:c25:c25a:d00a:4108
102c19:dd:d9:dd:c25:c25a:d00a:4109/1282c19:dd:d9:dd:c25:c25a:d00a:4109
112c19:dd:d9:dd:c25:c25a:d00a:410a/1282c19:dd:d9:dd:c25:c25a:d00a:410a
122c19:dd:d9:dd:c25:c25a:d00a:410b/1282c19:dd:d9:dd:c25:c25a:d00a:410b
132c19:dd:d9:dd:c25:c25a:d00a:410c/1282c19:dd:d9:dd:c25:c25a:d00a:410c
142c19:dd:d9:dd:c25:c25a:d00a:410d/1282c19:dd:d9:dd:c25:c25a:d00a:410d
152c19:dd:d9:dd:c25:c25a:d00a:410e/1282c19:dd:d9:dd:c25:c25a:d00a:410e
162c19:dd:d9:dd:c25:c25a:d00a:410f/1282c19:dd:d9:dd:c25:c25a:d00a:410f
172c19:dd:d9:dd:c25:c25a:d00a:4110/1282c19:dd:d9:dd:c25:c25a:d00a:4110
182c19:dd:d9:dd:c25:c25a:d00a:4111/1282c19:dd:d9:dd:c25:c25a:d00a:4111
192c19:dd:d9:dd:c25:c25a:d00a:4112/1282c19:dd:d9:dd:c25:c25a:d00a:4112
202c19:dd:d9:dd:c25:c25a:d00a:4113/1282c19:dd:d9:dd:c25:c25a:d00a:4113
212c19:dd:d9:dd:c25:c25a:d00a:4114/1282c19:dd:d9:dd:c25:c25a:d00a:4114
222c19:dd:d9:dd:c25:c25a:d00a:4115/1282c19:dd:d9:dd:c25:c25a:d00a:4115
232c19:dd:d9:dd:c25:c25a:d00a:4116/1282c19:dd:d9:dd:c25:c25a:d00a:4116
242c19:dd:d9:dd:c25:c25a:d00a:4117/1282c19:dd:d9:dd:c25:c25a:d00a:4117
252c19:dd:d9:dd:c25:c25a:d00a:4118/1282c19:dd:d9:dd:c25:c25a:d00a:4118
262c19:dd:d9:dd:c25:c25a:d00a:4119/1282c19:dd:d9:dd:c25:c25a:d00a:4119
272c19:dd:d9:dd:c25:c25a:d00a:411a/1282c19:dd:d9:dd:c25:c25a:d00a:411a
282c19:dd:d9:dd:c25:c25a:d00a:411b/1282c19:dd:d9:dd:c25:c25a:d00a:411b
292c19:dd:d9:dd:c25:c25a:d00a:411c/1282c19:dd:d9:dd:c25:c25a:d00a:411c
302c19:dd:d9:dd:c25:c25a:d00a:411d/1282c19:dd:d9:dd:c25:c25a:d00a:411d
312c19:dd:d9:dd:c25:c25a:d00a:411e/1282c19:dd:d9:dd:c25:c25a:d00a:411e
322c19:dd:d9:dd:c25:c25a:d00a:411f/1282c19:dd:d9:dd:c25:c25a:d00a:411f
332c19:dd:d9:dd:c25:c25a:d00a:4120/1282c19:dd:d9:dd:c25:c25a:d00a:4120
342c19:dd:d9:dd:c25:c25a:d00a:4121/1282c19:dd:d9:dd:c25:c25a:d00a:4121
352c19:dd:d9:dd:c25:c25a:d00a:4122/1282c19:dd:d9:dd:c25:c25a:d00a:4122
362c19:dd:d9:dd:c25:c25a:d00a:4123/1282c19:dd:d9:dd:c25:c25a:d00a:4123
372c19:dd:d9:dd:c25:c25a:d00a:4124/1282c19:dd:d9:dd:c25:c25a:d00a:4124
382c19:dd:d9:dd:c25:c25a:d00a:4125/1282c19:dd:d9:dd:c25:c25a:d00a:4125
392c19:dd:d9:dd:c25:c25a:d00a:4126/1282c19:dd:d9:dd:c25:c25a:d00a:4126
402c19:dd:d9:dd:c25:c25a:d00a:4127/1282c19:dd:d9:dd:c25:c25a:d00a:4127
412c19:dd:d9:dd:c25:c25a:d00a:4128/1282c19:dd:d9:dd:c25:c25a:d00a:4128
422c19:dd:d9:dd:c25:c25a:d00a:4129/1282c19:dd:d9:dd:c25:c25a:d00a:4129
432c19:dd:d9:dd:c25:c25a:d00a:412a/1282c19:dd:d9:dd:c25:c25a:d00a:412a
442c19:dd:d9:dd:c25:c25a:d00a:412b/1282c19:dd:d9:dd:c25:c25a:d00a:412b
452c19:dd:d9:dd:c25:c25a:d00a:412c/1282c19:dd:d9:dd:c25:c25a:d00a:412c
462c19:dd:d9:dd:c25:c25a:d00a:412d/1282c19:dd:d9:dd:c25:c25a:d00a:412d
472c19:dd:d9:dd:c25:c25a:d00a:412e/1282c19:dd:d9:dd:c25:c25a:d00a:412e
482c19:dd:d9:dd:c25:c25a:d00a:412f/1282c19:dd:d9:dd:c25:c25a:d00a:412f
492c19:dd:d9:dd:c25:c25a:d00a:4130/1282c19:dd:d9:dd:c25:c25a:d00a:4130
502c19:dd:d9:dd:c25:c25a:d00a:4131/1282c19:dd:d9:dd:c25:c25a:d00a:4131
512c19:dd:d9:dd:c25:c25a:d00a:4132/1282c19:dd:d9:dd:c25:c25a:d00a:4132
522c19:dd:d9:dd:c25:c25a:d00a:4133/1282c19:dd:d9:dd:c25:c25a:d00a:4133
532c19:dd:d9:dd:c25:c25a:d00a:4134/1282c19:dd:d9:dd:c25:c25a:d00a:4134
542c19:dd:d9:dd:c25:c25a:d00a:4135/1282c19:dd:d9:dd:c25:c25a:d00a:4135
552c19:dd:d9:dd:c25:c25a:d00a:4136/1282c19:dd:d9:dd:c25:c25a:d00a:4136
562c19:dd:d9:dd:c25:c25a:d00a:4137/1282c19:dd:d9:dd:c25:c25a:d00a:4137
572c19:dd:d9:dd:c25:c25a:d00a:4138/1282c19:dd:d9:dd:c25:c25a:d00a:4138
582c19:dd:d9:dd:c25:c25a:d00a:4139/1282c19:dd:d9:dd:c25:c25a:d00a:4139
592c19:dd:d9:dd:c25:c25a:d00a:413a/1282c19:dd:d9:dd:c25:c25a:d00a:413a
602c19:dd:d9:dd:c25:c25a:d00a:413b/1282c19:dd:d9:dd:c25:c25a:d00a:413b
612c19:dd:d9:dd:c25:c25a:d00a:413c/1282c19:dd:d9:dd:c25:c25a:d00a:413c
622c19:dd:d9:dd:c25:c25a:d00a:413d/1282c19:dd:d9:dd:c25:c25a:d00a:413d
632c19:dd:d9:dd:c25:c25a:d00a:413e/1282c19:dd:d9:dd:c25:c25a:d00a:413e
642c19:dd:d9:dd:c25:c25a:d00a:413f/1282c19:dd:d9:dd:c25:c25a:d00a:413f
652c19:dd:d9:dd:c25:c25a:d00a:4140/1282c19:dd:d9:dd:c25:c25a:d00a:4140
662c19:dd:d9:dd:c25:c25a:d00a:4141/1282c19:dd:d9:dd:c25:c25a:d00a:4141
672c19:dd:d9:dd:c25:c25a:d00a:4142/1282c19:dd:d9:dd:c25:c25a:d00a:4142
682c19:dd:d9:dd:c25:c25a:d00a:4143/1282c19:dd:d9:dd:c25:c25a:d00a:4143
692c19:dd:d9:dd:c25:c25a:d00a:4144/1282c19:dd:d9:dd:c25:c25a:d00a:4144
702c19:dd:d9:dd:c25:c25a:d00a:4145/1282c19:dd:d9:dd:c25:c25a:d00a:4145
712c19:dd:d9:dd:c25:c25a:d00a:4146/1282c19:dd:d9:dd:c25:c25a:d00a:4146
722c19:dd:d9:dd:c25:c25a:d00a:4147/1282c19:dd:d9:dd:c25:c25a:d00a:4147
732c19:dd:d9:dd:c25:c25a:d00a:4148/1282c19:dd:d9:dd:c25:c25a:d00a:4148
742c19:dd:d9:dd:c25:c25a:d00a:4149/1282c19:dd:d9:dd:c25:c25a:d00a:4149
752c19:dd:d9:dd:c25:c25a:d00a:414a/1282c19:dd:d9:dd:c25:c25a:d00a:414a
762c19:dd:d9:dd:c25:c25a:d00a:414b/1282c19:dd:d9:dd:c25:c25a:d00a:414b
772c19:dd:d9:dd:c25:c25a:d00a:414c/1282c19:dd:d9:dd:c25:c25a:d00a:414c
782c19:dd:d9:dd:c25:c25a:d00a:414d/1282c19:dd:d9:dd:c25:c25a:d00a:414d
792c19:dd:d9:dd:c25:c25a:d00a:414e/1282c19:dd:d9:dd:c25:c25a:d00a:414e
802c19:dd:d9:dd:c25:c25a:d00a:414f/1282c19:dd:d9:dd:c25:c25a:d00a:414f
812c19:dd:d9:dd:c25:c25a:d00a:4150/1282c19:dd:d9:dd:c25:c25a:d00a:4150
822c19:dd:d9:dd:c25:c25a:d00a:4151/1282c19:dd:d9:dd:c25:c25a:d00a:4151
832c19:dd:d9:dd:c25:c25a:d00a:4152/1282c19:dd:d9:dd:c25:c25a:d00a:4152
842c19:dd:d9:dd:c25:c25a:d00a:4153/1282c19:dd:d9:dd:c25:c25a:d00a:4153
852c19:dd:d9:dd:c25:c25a:d00a:4154/1282c19:dd:d9:dd:c25:c25a:d00a:4154
862c19:dd:d9:dd:c25:c25a:d00a:4155/1282c19:dd:d9:dd:c25:c25a:d00a:4155
872c19:dd:d9:dd:c25:c25a:d00a:4156/1282c19:dd:d9:dd:c25:c25a:d00a:4156
882c19:dd:d9:dd:c25:c25a:d00a:4157/1282c19:dd:d9:dd:c25:c25a:d00a:4157
892c19:dd:d9:dd:c25:c25a:d00a:4158/1282c19:dd:d9:dd:c25:c25a:d00a:4158
902c19:dd:d9:dd:c25:c25a:d00a:4159/1282c19:dd:d9:dd:c25:c25a:d00a:4159
912c19:dd:d9:dd:c25:c25a:d00a:415a/1282c19:dd:d9:dd:c25:c25a:d00a:415a
922c19:dd:d9:dd:c25:c25a:d00a:415b/1282c19:dd:d9:dd:c25:c25a:d00a:415b
932c19:dd:d9:dd:c25:c25a:d00a:415c/1282c19:dd:d9:dd:c25:c25a:d00a:415c
942c19:dd:d9:dd:c25:c25a:d00a:415d/1282c19:dd:d9:dd:c25:c25a:d00a:415d
952c19:dd:d9:dd:c25:c25a:d00a:415e/1282c19:dd:d9:dd:c25:c25a:d00a:415e
962c19:dd:d9:dd:c25:c25a:d00a:415f/1282c19:dd:d9:dd:c25:c25a:d00a:415f
972c19:dd:d9:dd:c25:c25a:d00a:4160/1282c19:dd:d9:dd:c25:c25a:d00a:4160
982c19:dd:d9:dd:c25:c25a:d00a:4161/1282c19:dd:d9:dd:c25:c25a:d00a:4161
992c19:dd:d9:dd:c25:c25a:d00a:4162/1282c19:dd:d9:dd:c25:c25a:d00a:4162
1002c19:dd:d9:dd:c25:c25a:d00a:4163/1282c19:dd:d9:dd:c25:c25a:d00a:4163
1012c19:dd:d9:dd:c25:c25a:d00a:4164/1282c19:dd:d9:dd:c25:c25a:d00a:4164
1022c19:dd:d9:dd:c25:c25a:d00a:4165/1282c19:dd:d9:dd:c25:c25a:d00a:4165
1032c19:dd:d9:dd:c25:c25a:d00a:4166/1282c19:dd:d9:dd:c25:c25a:d00a:4166
1042c19:dd:d9:dd:c25:c25a:d00a:4167/1282c19:dd:d9:dd:c25:c25a:d00a:4167
1052c19:dd:d9:dd:c25:c25a:d00a:4168/1282c19:dd:d9:dd:c25:c25a:d00a:4168
1062c19:dd:d9:dd:c25:c25a:d00a:4169/1282c19:dd:d9:dd:c25:c25a:d00a:4169
1072c19:dd:d9:dd:c25:c25a:d00a:416a/1282c19:dd:d9:dd:c25:c25a:d00a:416a
1082c19:dd:d9:dd:c25:c25a:d00a:416b/1282c19:dd:d9:dd:c25:c25a:d00a:416b
1092c19:dd:d9:dd:c25:c25a:d00a:416c/1282c19:dd:d9:dd:c25:c25a:d00a:416c
1102c19:dd:d9:dd:c25:c25a:d00a:416d/1282c19:dd:d9:dd:c25:c25a:d00a:416d
1112c19:dd:d9:dd:c25:c25a:d00a:416e/1282c19:dd:d9:dd:c25:c25a:d00a:416e
1122c19:dd:d9:dd:c25:c25a:d00a:416f/1282c19:dd:d9:dd:c25:c25a:d00a:416f
1132c19:dd:d9:dd:c25:c25a:d00a:4170/1282c19:dd:d9:dd:c25:c25a:d00a:4170
1142c19:dd:d9:dd:c25:c25a:d00a:4171/1282c19:dd:d9:dd:c25:c25a:d00a:4171
1152c19:dd:d9:dd:c25:c25a:d00a:4172/1282c19:dd:d9:dd:c25:c25a:d00a:4172
1162c19:dd:d9:dd:c25:c25a:d00a:4173/1282c19:dd:d9:dd:c25:c25a:d00a:4173
1172c19:dd:d9:dd:c25:c25a:d00a:4174/1282c19:dd:d9:dd:c25:c25a:d00a:4174
1182c19:dd:d9:dd:c25:c25a:d00a:4175/1282c19:dd:d9:dd:c25:c25a:d00a:4175
1192c19:dd:d9:dd:c25:c25a:d00a:4176/1282c19:dd:d9:dd:c25:c25a:d00a:4176
1202c19:dd:d9:dd:c25:c25a:d00a:4177/1282c19:dd:d9:dd:c25:c25a:d00a:4177
1212c19:dd:d9:dd:c25:c25a:d00a:4178/1282c19:dd:d9:dd:c25:c25a:d00a:4178
1222c19:dd:d9:dd:c25:c25a:d00a:4179/1282c19:dd:d9:dd:c25:c25a:d00a:4179
1232c19:dd:d9:dd:c25:c25a:d00a:417a/1282c19:dd:d9:dd:c25:c25a:d00a:417a
1242c19:dd:d9:dd:c25:c25a:d00a:417b/1282c19:dd:d9:dd:c25:c25a:d00a:417b
1252c19:dd:d9:dd:c25:c25a:d00a:417c/1282c19:dd:d9:dd:c25:c25a:d00a:417c
1262c19:dd:d9:dd:c25:c25a:d00a:417d/1282c19:dd:d9:dd:c25:c25a:d00a:417d
1272c19:dd:d9:dd:c25:c25a:d00a:417e/1282c19:dd:d9:dd:c25:c25a:d00a:417e
1282c19:dd:d9:dd:c25:c25a:d00a:417f/1282c19:dd:d9:dd:c25:c25a:d00a:417f
1292c19:dd:d9:dd:c25:c25a:d00a:4180/1282c19:dd:d9:dd:c25:c25a:d00a:4180
1302c19:dd:d9:dd:c25:c25a:d00a:4181/1282c19:dd:d9:dd:c25:c25a:d00a:4181
1312c19:dd:d9:dd:c25:c25a:d00a:4182/1282c19:dd:d9:dd:c25:c25a:d00a:4182
1322c19:dd:d9:dd:c25:c25a:d00a:4183/1282c19:dd:d9:dd:c25:c25a:d00a:4183
1332c19:dd:d9:dd:c25:c25a:d00a:4184/1282c19:dd:d9:dd:c25:c25a:d00a:4184
1342c19:dd:d9:dd:c25:c25a:d00a:4185/1282c19:dd:d9:dd:c25:c25a:d00a:4185
1352c19:dd:d9:dd:c25:c25a:d00a:4186/1282c19:dd:d9:dd:c25:c25a:d00a:4186
1362c19:dd:d9:dd:c25:c25a:d00a:4187/1282c19:dd:d9:dd:c25:c25a:d00a:4187
1372c19:dd:d9:dd:c25:c25a:d00a:4188/1282c19:dd:d9:dd:c25:c25a:d00a:4188
1382c19:dd:d9:dd:c25:c25a:d00a:4189/1282c19:dd:d9:dd:c25:c25a:d00a:4189
1392c19:dd:d9:dd:c25:c25a:d00a:418a/1282c19:dd:d9:dd:c25:c25a:d00a:418a
1402c19:dd:d9:dd:c25:c25a:d00a:418b/1282c19:dd:d9:dd:c25:c25a:d00a:418b
1412c19:dd:d9:dd:c25:c25a:d00a:418c/1282c19:dd:d9:dd:c25:c25a:d00a:418c
1422c19:dd:d9:dd:c25:c25a:d00a:418d/1282c19:dd:d9:dd:c25:c25a:d00a:418d
1432c19:dd:d9:dd:c25:c25a:d00a:418e/1282c19:dd:d9:dd:c25:c25a:d00a:418e
1442c19:dd:d9:dd:c25:c25a:d00a:418f/1282c19:dd:d9:dd:c25:c25a:d00a:418f
1452c19:dd:d9:dd:c25:c25a:d00a:4190/1282c19:dd:d9:dd:c25:c25a:d00a:4190
1462c19:dd:d9:dd:c25:c25a:d00a:4191/1282c19:dd:d9:dd:c25:c25a:d00a:4191
1472c19:dd:d9:dd:c25:c25a:d00a:4192/1282c19:dd:d9:dd:c25:c25a:d00a:4192
1482c19:dd:d9:dd:c25:c25a:d00a:4193/1282c19:dd:d9:dd:c25:c25a:d00a:4193
1492c19:dd:d9:dd:c25:c25a:d00a:4194/1282c19:dd:d9:dd:c25:c25a:d00a:4194
1502c19:dd:d9:dd:c25:c25a:d00a:4195/1282c19:dd:d9:dd:c25:c25a:d00a:4195
1512c19:dd:d9:dd:c25:c25a:d00a:4196/1282c19:dd:d9:dd:c25:c25a:d00a:4196
1522c19:dd:d9:dd:c25:c25a:d00a:4197/1282c19:dd:d9:dd:c25:c25a:d00a:4197
1532c19:dd:d9:dd:c25:c25a:d00a:4198/1282c19:dd:d9:dd:c25:c25a:d00a:4198
1542c19:dd:d9:dd:c25:c25a:d00a:4199/1282c19:dd:d9:dd:c25:c25a:d00a:4199
1552c19:dd:d9:dd:c25:c25a:d00a:419a/1282c19:dd:d9:dd:c25:c25a:d00a:419a
1562c19:dd:d9:dd:c25:c25a:d00a:419b/1282c19:dd:d9:dd:c25:c25a:d00a:419b
1572c19:dd:d9:dd:c25:c25a:d00a:419c/1282c19:dd:d9:dd:c25:c25a:d00a:419c
1582c19:dd:d9:dd:c25:c25a:d00a:419d/1282c19:dd:d9:dd:c25:c25a:d00a:419d
1592c19:dd:d9:dd:c25:c25a:d00a:419e/1282c19:dd:d9:dd:c25:c25a:d00a:419e
1602c19:dd:d9:dd:c25:c25a:d00a:419f/1282c19:dd:d9:dd:c25:c25a:d00a:419f
1612c19:dd:d9:dd:c25:c25a:d00a:41a0/1282c19:dd:d9:dd:c25:c25a:d00a:41a0
1622c19:dd:d9:dd:c25:c25a:d00a:41a1/1282c19:dd:d9:dd:c25:c25a:d00a:41a1
1632c19:dd:d9:dd:c25:c25a:d00a:41a2/1282c19:dd:d9:dd:c25:c25a:d00a:41a2
1642c19:dd:d9:dd:c25:c25a:d00a:41a3/1282c19:dd:d9:dd:c25:c25a:d00a:41a3
1652c19:dd:d9:dd:c25:c25a:d00a:41a4/1282c19:dd:d9:dd:c25:c25a:d00a:41a4
1662c19:dd:d9:dd:c25:c25a:d00a:41a5/1282c19:dd:d9:dd:c25:c25a:d00a:41a5
1672c19:dd:d9:dd:c25:c25a:d00a:41a6/1282c19:dd:d9:dd:c25:c25a:d00a:41a6
1682c19:dd:d9:dd:c25:c25a:d00a:41a7/1282c19:dd:d9:dd:c25:c25a:d00a:41a7
1692c19:dd:d9:dd:c25:c25a:d00a:41a8/1282c19:dd:d9:dd:c25:c25a:d00a:41a8
1702c19:dd:d9:dd:c25:c25a:d00a:41a9/1282c19:dd:d9:dd:c25:c25a:d00a:41a9
1712c19:dd:d9:dd:c25:c25a:d00a:41aa/1282c19:dd:d9:dd:c25:c25a:d00a:41aa
1722c19:dd:d9:dd:c25:c25a:d00a:41ab/1282c19:dd:d9:dd:c25:c25a:d00a:41ab
1732c19:dd:d9:dd:c25:c25a:d00a:41ac/1282c19:dd:d9:dd:c25:c25a:d00a:41ac
1742c19:dd:d9:dd:c25:c25a:d00a:41ad/1282c19:dd:d9:dd:c25:c25a:d00a:41ad
1752c19:dd:d9:dd:c25:c25a:d00a:41ae/1282c19:dd:d9:dd:c25:c25a:d00a:41ae
1762c19:dd:d9:dd:c25:c25a:d00a:41af/1282c19:dd:d9:dd:c25:c25a:d00a:41af
1772c19:dd:d9:dd:c25:c25a:d00a:41b0/1282c19:dd:d9:dd:c25:c25a:d00a:41b0
1782c19:dd:d9:dd:c25:c25a:d00a:41b1/1282c19:dd:d9:dd:c25:c25a:d00a:41b1
1792c19:dd:d9:dd:c25:c25a:d00a:41b2/1282c19:dd:d9:dd:c25:c25a:d00a:41b2
1802c19:dd:d9:dd:c25:c25a:d00a:41b3/1282c19:dd:d9:dd:c25:c25a:d00a:41b3
1812c19:dd:d9:dd:c25:c25a:d00a:41b4/1282c19:dd:d9:dd:c25:c25a:d00a:41b4
1822c19:dd:d9:dd:c25:c25a:d00a:41b5/1282c19:dd:d9:dd:c25:c25a:d00a:41b5
1832c19:dd:d9:dd:c25:c25a:d00a:41b6/1282c19:dd:d9:dd:c25:c25a:d00a:41b6
1842c19:dd:d9:dd:c25:c25a:d00a:41b7/1282c19:dd:d9:dd:c25:c25a:d00a:41b7
1852c19:dd:d9:dd:c25:c25a:d00a:41b8/1282c19:dd:d9:dd:c25:c25a:d00a:41b8
1862c19:dd:d9:dd:c25:c25a:d00a:41b9/1282c19:dd:d9:dd:c25:c25a:d00a:41b9
1872c19:dd:d9:dd:c25:c25a:d00a:41ba/1282c19:dd:d9:dd:c25:c25a:d00a:41ba
1882c19:dd:d9:dd:c25:c25a:d00a:41bb/1282c19:dd:d9:dd:c25:c25a:d00a:41bb
1892c19:dd:d9:dd:c25:c25a:d00a:41bc/1282c19:dd:d9:dd:c25:c25a:d00a:41bc
1902c19:dd:d9:dd:c25:c25a:d00a:41bd/1282c19:dd:d9:dd:c25:c25a:d00a:41bd
1912c19:dd:d9:dd:c25:c25a:d00a:41be/1282c19:dd:d9:dd:c25:c25a:d00a:41be
1922c19:dd:d9:dd:c25:c25a:d00a:41bf/1282c19:dd:d9:dd:c25:c25a:d00a:41bf
1932c19:dd:d9:dd:c25:c25a:d00a:41c0/1282c19:dd:d9:dd:c25:c25a:d00a:41c0
1942c19:dd:d9:dd:c25:c25a:d00a:41c1/1282c19:dd:d9:dd:c25:c25a:d00a:41c1
1952c19:dd:d9:dd:c25:c25a:d00a:41c2/1282c19:dd:d9:dd:c25:c25a:d00a:41c2
1962c19:dd:d9:dd:c25:c25a:d00a:41c3/1282c19:dd:d9:dd:c25:c25a:d00a:41c3
1972c19:dd:d9:dd:c25:c25a:d00a:41c4/1282c19:dd:d9:dd:c25:c25a:d00a:41c4
1982c19:dd:d9:dd:c25:c25a:d00a:41c5/1282c19:dd:d9:dd:c25:c25a:d00a:41c5
1992c19:dd:d9:dd:c25:c25a:d00a:41c6/1282c19:dd:d9:dd:c25:c25a:d00a:41c6
2002c19:dd:d9:dd:c25:c25a:d00a:41c7/1282c19:dd:d9:dd:c25:c25a:d00a:41c7
2012c19:dd:d9:dd:c25:c25a:d00a:41c8/1282c19:dd:d9:dd:c25:c25a:d00a:41c8
2022c19:dd:d9:dd:c25:c25a:d00a:41c9/1282c19:dd:d9:dd:c25:c25a:d00a:41c9
2032c19:dd:d9:dd:c25:c25a:d00a:41ca/1282c19:dd:d9:dd:c25:c25a:d00a:41ca
2042c19:dd:d9:dd:c25:c25a:d00a:41cb/1282c19:dd:d9:dd:c25:c25a:d00a:41cb
2052c19:dd:d9:dd:c25:c25a:d00a:41cc/1282c19:dd:d9:dd:c25:c25a:d00a:41cc
2062c19:dd:d9:dd:c25:c25a:d00a:41cd/1282c19:dd:d9:dd:c25:c25a:d00a:41cd
2072c19:dd:d9:dd:c25:c25a:d00a:41ce/1282c19:dd:d9:dd:c25:c25a:d00a:41ce
2082c19:dd:d9:dd:c25:c25a:d00a:41cf/1282c19:dd:d9:dd:c25:c25a:d00a:41cf
2092c19:dd:d9:dd:c25:c25a:d00a:41d0/1282c19:dd:d9:dd:c25:c25a:d00a:41d0
2102c19:dd:d9:dd:c25:c25a:d00a:41d1/1282c19:dd:d9:dd:c25:c25a:d00a:41d1
2112c19:dd:d9:dd:c25:c25a:d00a:41d2/1282c19:dd:d9:dd:c25:c25a:d00a:41d2
2122c19:dd:d9:dd:c25:c25a:d00a:41d3/1282c19:dd:d9:dd:c25:c25a:d00a:41d3
2132c19:dd:d9:dd:c25:c25a:d00a:41d4/1282c19:dd:d9:dd:c25:c25a:d00a:41d4
2142c19:dd:d9:dd:c25:c25a:d00a:41d5/1282c19:dd:d9:dd:c25:c25a:d00a:41d5
2152c19:dd:d9:dd:c25:c25a:d00a:41d6/1282c19:dd:d9:dd:c25:c25a:d00a:41d6
2162c19:dd:d9:dd:c25:c25a:d00a:41d7/1282c19:dd:d9:dd:c25:c25a:d00a:41d7
2172c19:dd:d9:dd:c25:c25a:d00a:41d8/1282c19:dd:d9:dd:c25:c25a:d00a:41d8
2182c19:dd:d9:dd:c25:c25a:d00a:41d9/1282c19:dd:d9:dd:c25:c25a:d00a:41d9
2192c19:dd:d9:dd:c25:c25a:d00a:41da/1282c19:dd:d9:dd:c25:c25a:d00a:41da
2202c19:dd:d9:dd:c25:c25a:d00a:41db/1282c19:dd:d9:dd:c25:c25a:d00a:41db
2212c19:dd:d9:dd:c25:c25a:d00a:41dc/1282c19:dd:d9:dd:c25:c25a:d00a:41dc
2222c19:dd:d9:dd:c25:c25a:d00a:41dd/1282c19:dd:d9:dd:c25:c25a:d00a:41dd
2232c19:dd:d9:dd:c25:c25a:d00a:41de/1282c19:dd:d9:dd:c25:c25a:d00a:41de
2242c19:dd:d9:dd:c25:c25a:d00a:41df/1282c19:dd:d9:dd:c25:c25a:d00a:41df
2252c19:dd:d9:dd:c25:c25a:d00a:41e0/1282c19:dd:d9:dd:c25:c25a:d00a:41e0
2262c19:dd:d9:dd:c25:c25a:d00a:41e1/1282c19:dd:d9:dd:c25:c25a:d00a:41e1
2272c19:dd:d9:dd:c25:c25a:d00a:41e2/1282c19:dd:d9:dd:c25:c25a:d00a:41e2
2282c19:dd:d9:dd:c25:c25a:d00a:41e3/1282c19:dd:d9:dd:c25:c25a:d00a:41e3
2292c19:dd:d9:dd:c25:c25a:d00a:41e4/1282c19:dd:d9:dd:c25:c25a:d00a:41e4
2302c19:dd:d9:dd:c25:c25a:d00a:41e5/1282c19:dd:d9:dd:c25:c25a:d00a:41e5
2312c19:dd:d9:dd:c25:c25a:d00a:41e6/1282c19:dd:d9:dd:c25:c25a:d00a:41e6
2322c19:dd:d9:dd:c25:c25a:d00a:41e7/1282c19:dd:d9:dd:c25:c25a:d00a:41e7
2332c19:dd:d9:dd:c25:c25a:d00a:41e8/1282c19:dd:d9:dd:c25:c25a:d00a:41e8
2342c19:dd:d9:dd:c25:c25a:d00a:41e9/1282c19:dd:d9:dd:c25:c25a:d00a:41e9
2352c19:dd:d9:dd:c25:c25a:d00a:41ea/1282c19:dd:d9:dd:c25:c25a:d00a:41ea
2362c19:dd:d9:dd:c25:c25a:d00a:41eb/1282c19:dd:d9:dd:c25:c25a:d00a:41eb
2372c19:dd:d9:dd:c25:c25a:d00a:41ec/1282c19:dd:d9:dd:c25:c25a:d00a:41ec
2382c19:dd:d9:dd:c25:c25a:d00a:41ed/1282c19:dd:d9:dd:c25:c25a:d00a:41ed
2392c19:dd:d9:dd:c25:c25a:d00a:41ee/1282c19:dd:d9:dd:c25:c25a:d00a:41ee
2402c19:dd:d9:dd:c25:c25a:d00a:41ef/1282c19:dd:d9:dd:c25:c25a:d00a:41ef
2412c19:dd:d9:dd:c25:c25a:d00a:41f0/1282c19:dd:d9:dd:c25:c25a:d00a:41f0
2422c19:dd:d9:dd:c25:c25a:d00a:41f1/1282c19:dd:d9:dd:c25:c25a:d00a:41f1
2432c19:dd:d9:dd:c25:c25a:d00a:41f2/1282c19:dd:d9:dd:c25:c25a:d00a:41f2
2442c19:dd:d9:dd:c25:c25a:d00a:41f3/1282c19:dd:d9:dd:c25:c25a:d00a:41f3
2452c19:dd:d9:dd:c25:c25a:d00a:41f4/1282c19:dd:d9:dd:c25:c25a:d00a:41f4
2462c19:dd:d9:dd:c25:c25a:d00a:41f5/1282c19:dd:d9:dd:c25:c25a:d00a:41f5
2472c19:dd:d9:dd:c25:c25a:d00a:41f6/1282c19:dd:d9:dd:c25:c25a:d00a:41f6
2482c19:dd:d9:dd:c25:c25a:d00a:41f7/1282c19:dd:d9:dd:c25:c25a:d00a:41f7
2492c19:dd:d9:dd:c25:c25a:d00a:41f8/1282c19:dd:d9:dd:c25:c25a:d00a:41f8
2502c19:dd:d9:dd:c25:c25a:d00a:41f9/1282c19:dd:d9:dd:c25:c25a:d00a:41f9
2512c19:dd:d9:dd:c25:c25a:d00a:41fa/1282c19:dd:d9:dd:c25:c25a:d00a:41fa
2522c19:dd:d9:dd:c25:c25a:d00a:41fb/1282c19:dd:d9:dd:c25:c25a:d00a:41fb
2532c19:dd:d9:dd:c25:c25a:d00a:41fc/1282c19:dd:d9:dd:c25:c25a:d00a:41fc
2542c19:dd:d9:dd:c25:c25a:d00a:41fd/1282c19:dd:d9:dd:c25:c25a:d00a:41fd
2552c19:dd:d9:dd:c25:c25a:d00a:41fe/1282c19:dd:d9:dd:c25:c25a:d00a:41fe
2562c19:dd:d9:dd:c25:c25a:d00a:41ff/1282c19:dd:d9:dd:c25:c25a:d00a:41ff

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.