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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:d100/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:d100
Last address
2c19:dd:d9:dd:c25:c25a:d00a:d1ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:d100
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
1.d.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:d100/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:d100/1282c19:dd:d9:dd:c25:c25a:d00a:d100
22c19:dd:d9:dd:c25:c25a:d00a:d101/1282c19:dd:d9:dd:c25:c25a:d00a:d101
32c19:dd:d9:dd:c25:c25a:d00a:d102/1282c19:dd:d9:dd:c25:c25a:d00a:d102
42c19:dd:d9:dd:c25:c25a:d00a:d103/1282c19:dd:d9:dd:c25:c25a:d00a:d103
52c19:dd:d9:dd:c25:c25a:d00a:d104/1282c19:dd:d9:dd:c25:c25a:d00a:d104
62c19:dd:d9:dd:c25:c25a:d00a:d105/1282c19:dd:d9:dd:c25:c25a:d00a:d105
72c19:dd:d9:dd:c25:c25a:d00a:d106/1282c19:dd:d9:dd:c25:c25a:d00a:d106
82c19:dd:d9:dd:c25:c25a:d00a:d107/1282c19:dd:d9:dd:c25:c25a:d00a:d107
92c19:dd:d9:dd:c25:c25a:d00a:d108/1282c19:dd:d9:dd:c25:c25a:d00a:d108
102c19:dd:d9:dd:c25:c25a:d00a:d109/1282c19:dd:d9:dd:c25:c25a:d00a:d109
112c19:dd:d9:dd:c25:c25a:d00a:d10a/1282c19:dd:d9:dd:c25:c25a:d00a:d10a
122c19:dd:d9:dd:c25:c25a:d00a:d10b/1282c19:dd:d9:dd:c25:c25a:d00a:d10b
132c19:dd:d9:dd:c25:c25a:d00a:d10c/1282c19:dd:d9:dd:c25:c25a:d00a:d10c
142c19:dd:d9:dd:c25:c25a:d00a:d10d/1282c19:dd:d9:dd:c25:c25a:d00a:d10d
152c19:dd:d9:dd:c25:c25a:d00a:d10e/1282c19:dd:d9:dd:c25:c25a:d00a:d10e
162c19:dd:d9:dd:c25:c25a:d00a:d10f/1282c19:dd:d9:dd:c25:c25a:d00a:d10f
172c19:dd:d9:dd:c25:c25a:d00a:d110/1282c19:dd:d9:dd:c25:c25a:d00a:d110
182c19:dd:d9:dd:c25:c25a:d00a:d111/1282c19:dd:d9:dd:c25:c25a:d00a:d111
192c19:dd:d9:dd:c25:c25a:d00a:d112/1282c19:dd:d9:dd:c25:c25a:d00a:d112
202c19:dd:d9:dd:c25:c25a:d00a:d113/1282c19:dd:d9:dd:c25:c25a:d00a:d113
212c19:dd:d9:dd:c25:c25a:d00a:d114/1282c19:dd:d9:dd:c25:c25a:d00a:d114
222c19:dd:d9:dd:c25:c25a:d00a:d115/1282c19:dd:d9:dd:c25:c25a:d00a:d115
232c19:dd:d9:dd:c25:c25a:d00a:d116/1282c19:dd:d9:dd:c25:c25a:d00a:d116
242c19:dd:d9:dd:c25:c25a:d00a:d117/1282c19:dd:d9:dd:c25:c25a:d00a:d117
252c19:dd:d9:dd:c25:c25a:d00a:d118/1282c19:dd:d9:dd:c25:c25a:d00a:d118
262c19:dd:d9:dd:c25:c25a:d00a:d119/1282c19:dd:d9:dd:c25:c25a:d00a:d119
272c19:dd:d9:dd:c25:c25a:d00a:d11a/1282c19:dd:d9:dd:c25:c25a:d00a:d11a
282c19:dd:d9:dd:c25:c25a:d00a:d11b/1282c19:dd:d9:dd:c25:c25a:d00a:d11b
292c19:dd:d9:dd:c25:c25a:d00a:d11c/1282c19:dd:d9:dd:c25:c25a:d00a:d11c
302c19:dd:d9:dd:c25:c25a:d00a:d11d/1282c19:dd:d9:dd:c25:c25a:d00a:d11d
312c19:dd:d9:dd:c25:c25a:d00a:d11e/1282c19:dd:d9:dd:c25:c25a:d00a:d11e
322c19:dd:d9:dd:c25:c25a:d00a:d11f/1282c19:dd:d9:dd:c25:c25a:d00a:d11f
332c19:dd:d9:dd:c25:c25a:d00a:d120/1282c19:dd:d9:dd:c25:c25a:d00a:d120
342c19:dd:d9:dd:c25:c25a:d00a:d121/1282c19:dd:d9:dd:c25:c25a:d00a:d121
352c19:dd:d9:dd:c25:c25a:d00a:d122/1282c19:dd:d9:dd:c25:c25a:d00a:d122
362c19:dd:d9:dd:c25:c25a:d00a:d123/1282c19:dd:d9:dd:c25:c25a:d00a:d123
372c19:dd:d9:dd:c25:c25a:d00a:d124/1282c19:dd:d9:dd:c25:c25a:d00a:d124
382c19:dd:d9:dd:c25:c25a:d00a:d125/1282c19:dd:d9:dd:c25:c25a:d00a:d125
392c19:dd:d9:dd:c25:c25a:d00a:d126/1282c19:dd:d9:dd:c25:c25a:d00a:d126
402c19:dd:d9:dd:c25:c25a:d00a:d127/1282c19:dd:d9:dd:c25:c25a:d00a:d127
412c19:dd:d9:dd:c25:c25a:d00a:d128/1282c19:dd:d9:dd:c25:c25a:d00a:d128
422c19:dd:d9:dd:c25:c25a:d00a:d129/1282c19:dd:d9:dd:c25:c25a:d00a:d129
432c19:dd:d9:dd:c25:c25a:d00a:d12a/1282c19:dd:d9:dd:c25:c25a:d00a:d12a
442c19:dd:d9:dd:c25:c25a:d00a:d12b/1282c19:dd:d9:dd:c25:c25a:d00a:d12b
452c19:dd:d9:dd:c25:c25a:d00a:d12c/1282c19:dd:d9:dd:c25:c25a:d00a:d12c
462c19:dd:d9:dd:c25:c25a:d00a:d12d/1282c19:dd:d9:dd:c25:c25a:d00a:d12d
472c19:dd:d9:dd:c25:c25a:d00a:d12e/1282c19:dd:d9:dd:c25:c25a:d00a:d12e
482c19:dd:d9:dd:c25:c25a:d00a:d12f/1282c19:dd:d9:dd:c25:c25a:d00a:d12f
492c19:dd:d9:dd:c25:c25a:d00a:d130/1282c19:dd:d9:dd:c25:c25a:d00a:d130
502c19:dd:d9:dd:c25:c25a:d00a:d131/1282c19:dd:d9:dd:c25:c25a:d00a:d131
512c19:dd:d9:dd:c25:c25a:d00a:d132/1282c19:dd:d9:dd:c25:c25a:d00a:d132
522c19:dd:d9:dd:c25:c25a:d00a:d133/1282c19:dd:d9:dd:c25:c25a:d00a:d133
532c19:dd:d9:dd:c25:c25a:d00a:d134/1282c19:dd:d9:dd:c25:c25a:d00a:d134
542c19:dd:d9:dd:c25:c25a:d00a:d135/1282c19:dd:d9:dd:c25:c25a:d00a:d135
552c19:dd:d9:dd:c25:c25a:d00a:d136/1282c19:dd:d9:dd:c25:c25a:d00a:d136
562c19:dd:d9:dd:c25:c25a:d00a:d137/1282c19:dd:d9:dd:c25:c25a:d00a:d137
572c19:dd:d9:dd:c25:c25a:d00a:d138/1282c19:dd:d9:dd:c25:c25a:d00a:d138
582c19:dd:d9:dd:c25:c25a:d00a:d139/1282c19:dd:d9:dd:c25:c25a:d00a:d139
592c19:dd:d9:dd:c25:c25a:d00a:d13a/1282c19:dd:d9:dd:c25:c25a:d00a:d13a
602c19:dd:d9:dd:c25:c25a:d00a:d13b/1282c19:dd:d9:dd:c25:c25a:d00a:d13b
612c19:dd:d9:dd:c25:c25a:d00a:d13c/1282c19:dd:d9:dd:c25:c25a:d00a:d13c
622c19:dd:d9:dd:c25:c25a:d00a:d13d/1282c19:dd:d9:dd:c25:c25a:d00a:d13d
632c19:dd:d9:dd:c25:c25a:d00a:d13e/1282c19:dd:d9:dd:c25:c25a:d00a:d13e
642c19:dd:d9:dd:c25:c25a:d00a:d13f/1282c19:dd:d9:dd:c25:c25a:d00a:d13f
652c19:dd:d9:dd:c25:c25a:d00a:d140/1282c19:dd:d9:dd:c25:c25a:d00a:d140
662c19:dd:d9:dd:c25:c25a:d00a:d141/1282c19:dd:d9:dd:c25:c25a:d00a:d141
672c19:dd:d9:dd:c25:c25a:d00a:d142/1282c19:dd:d9:dd:c25:c25a:d00a:d142
682c19:dd:d9:dd:c25:c25a:d00a:d143/1282c19:dd:d9:dd:c25:c25a:d00a:d143
692c19:dd:d9:dd:c25:c25a:d00a:d144/1282c19:dd:d9:dd:c25:c25a:d00a:d144
702c19:dd:d9:dd:c25:c25a:d00a:d145/1282c19:dd:d9:dd:c25:c25a:d00a:d145
712c19:dd:d9:dd:c25:c25a:d00a:d146/1282c19:dd:d9:dd:c25:c25a:d00a:d146
722c19:dd:d9:dd:c25:c25a:d00a:d147/1282c19:dd:d9:dd:c25:c25a:d00a:d147
732c19:dd:d9:dd:c25:c25a:d00a:d148/1282c19:dd:d9:dd:c25:c25a:d00a:d148
742c19:dd:d9:dd:c25:c25a:d00a:d149/1282c19:dd:d9:dd:c25:c25a:d00a:d149
752c19:dd:d9:dd:c25:c25a:d00a:d14a/1282c19:dd:d9:dd:c25:c25a:d00a:d14a
762c19:dd:d9:dd:c25:c25a:d00a:d14b/1282c19:dd:d9:dd:c25:c25a:d00a:d14b
772c19:dd:d9:dd:c25:c25a:d00a:d14c/1282c19:dd:d9:dd:c25:c25a:d00a:d14c
782c19:dd:d9:dd:c25:c25a:d00a:d14d/1282c19:dd:d9:dd:c25:c25a:d00a:d14d
792c19:dd:d9:dd:c25:c25a:d00a:d14e/1282c19:dd:d9:dd:c25:c25a:d00a:d14e
802c19:dd:d9:dd:c25:c25a:d00a:d14f/1282c19:dd:d9:dd:c25:c25a:d00a:d14f
812c19:dd:d9:dd:c25:c25a:d00a:d150/1282c19:dd:d9:dd:c25:c25a:d00a:d150
822c19:dd:d9:dd:c25:c25a:d00a:d151/1282c19:dd:d9:dd:c25:c25a:d00a:d151
832c19:dd:d9:dd:c25:c25a:d00a:d152/1282c19:dd:d9:dd:c25:c25a:d00a:d152
842c19:dd:d9:dd:c25:c25a:d00a:d153/1282c19:dd:d9:dd:c25:c25a:d00a:d153
852c19:dd:d9:dd:c25:c25a:d00a:d154/1282c19:dd:d9:dd:c25:c25a:d00a:d154
862c19:dd:d9:dd:c25:c25a:d00a:d155/1282c19:dd:d9:dd:c25:c25a:d00a:d155
872c19:dd:d9:dd:c25:c25a:d00a:d156/1282c19:dd:d9:dd:c25:c25a:d00a:d156
882c19:dd:d9:dd:c25:c25a:d00a:d157/1282c19:dd:d9:dd:c25:c25a:d00a:d157
892c19:dd:d9:dd:c25:c25a:d00a:d158/1282c19:dd:d9:dd:c25:c25a:d00a:d158
902c19:dd:d9:dd:c25:c25a:d00a:d159/1282c19:dd:d9:dd:c25:c25a:d00a:d159
912c19:dd:d9:dd:c25:c25a:d00a:d15a/1282c19:dd:d9:dd:c25:c25a:d00a:d15a
922c19:dd:d9:dd:c25:c25a:d00a:d15b/1282c19:dd:d9:dd:c25:c25a:d00a:d15b
932c19:dd:d9:dd:c25:c25a:d00a:d15c/1282c19:dd:d9:dd:c25:c25a:d00a:d15c
942c19:dd:d9:dd:c25:c25a:d00a:d15d/1282c19:dd:d9:dd:c25:c25a:d00a:d15d
952c19:dd:d9:dd:c25:c25a:d00a:d15e/1282c19:dd:d9:dd:c25:c25a:d00a:d15e
962c19:dd:d9:dd:c25:c25a:d00a:d15f/1282c19:dd:d9:dd:c25:c25a:d00a:d15f
972c19:dd:d9:dd:c25:c25a:d00a:d160/1282c19:dd:d9:dd:c25:c25a:d00a:d160
982c19:dd:d9:dd:c25:c25a:d00a:d161/1282c19:dd:d9:dd:c25:c25a:d00a:d161
992c19:dd:d9:dd:c25:c25a:d00a:d162/1282c19:dd:d9:dd:c25:c25a:d00a:d162
1002c19:dd:d9:dd:c25:c25a:d00a:d163/1282c19:dd:d9:dd:c25:c25a:d00a:d163
1012c19:dd:d9:dd:c25:c25a:d00a:d164/1282c19:dd:d9:dd:c25:c25a:d00a:d164
1022c19:dd:d9:dd:c25:c25a:d00a:d165/1282c19:dd:d9:dd:c25:c25a:d00a:d165
1032c19:dd:d9:dd:c25:c25a:d00a:d166/1282c19:dd:d9:dd:c25:c25a:d00a:d166
1042c19:dd:d9:dd:c25:c25a:d00a:d167/1282c19:dd:d9:dd:c25:c25a:d00a:d167
1052c19:dd:d9:dd:c25:c25a:d00a:d168/1282c19:dd:d9:dd:c25:c25a:d00a:d168
1062c19:dd:d9:dd:c25:c25a:d00a:d169/1282c19:dd:d9:dd:c25:c25a:d00a:d169
1072c19:dd:d9:dd:c25:c25a:d00a:d16a/1282c19:dd:d9:dd:c25:c25a:d00a:d16a
1082c19:dd:d9:dd:c25:c25a:d00a:d16b/1282c19:dd:d9:dd:c25:c25a:d00a:d16b
1092c19:dd:d9:dd:c25:c25a:d00a:d16c/1282c19:dd:d9:dd:c25:c25a:d00a:d16c
1102c19:dd:d9:dd:c25:c25a:d00a:d16d/1282c19:dd:d9:dd:c25:c25a:d00a:d16d
1112c19:dd:d9:dd:c25:c25a:d00a:d16e/1282c19:dd:d9:dd:c25:c25a:d00a:d16e
1122c19:dd:d9:dd:c25:c25a:d00a:d16f/1282c19:dd:d9:dd:c25:c25a:d00a:d16f
1132c19:dd:d9:dd:c25:c25a:d00a:d170/1282c19:dd:d9:dd:c25:c25a:d00a:d170
1142c19:dd:d9:dd:c25:c25a:d00a:d171/1282c19:dd:d9:dd:c25:c25a:d00a:d171
1152c19:dd:d9:dd:c25:c25a:d00a:d172/1282c19:dd:d9:dd:c25:c25a:d00a:d172
1162c19:dd:d9:dd:c25:c25a:d00a:d173/1282c19:dd:d9:dd:c25:c25a:d00a:d173
1172c19:dd:d9:dd:c25:c25a:d00a:d174/1282c19:dd:d9:dd:c25:c25a:d00a:d174
1182c19:dd:d9:dd:c25:c25a:d00a:d175/1282c19:dd:d9:dd:c25:c25a:d00a:d175
1192c19:dd:d9:dd:c25:c25a:d00a:d176/1282c19:dd:d9:dd:c25:c25a:d00a:d176
1202c19:dd:d9:dd:c25:c25a:d00a:d177/1282c19:dd:d9:dd:c25:c25a:d00a:d177
1212c19:dd:d9:dd:c25:c25a:d00a:d178/1282c19:dd:d9:dd:c25:c25a:d00a:d178
1222c19:dd:d9:dd:c25:c25a:d00a:d179/1282c19:dd:d9:dd:c25:c25a:d00a:d179
1232c19:dd:d9:dd:c25:c25a:d00a:d17a/1282c19:dd:d9:dd:c25:c25a:d00a:d17a
1242c19:dd:d9:dd:c25:c25a:d00a:d17b/1282c19:dd:d9:dd:c25:c25a:d00a:d17b
1252c19:dd:d9:dd:c25:c25a:d00a:d17c/1282c19:dd:d9:dd:c25:c25a:d00a:d17c
1262c19:dd:d9:dd:c25:c25a:d00a:d17d/1282c19:dd:d9:dd:c25:c25a:d00a:d17d
1272c19:dd:d9:dd:c25:c25a:d00a:d17e/1282c19:dd:d9:dd:c25:c25a:d00a:d17e
1282c19:dd:d9:dd:c25:c25a:d00a:d17f/1282c19:dd:d9:dd:c25:c25a:d00a:d17f
1292c19:dd:d9:dd:c25:c25a:d00a:d180/1282c19:dd:d9:dd:c25:c25a:d00a:d180
1302c19:dd:d9:dd:c25:c25a:d00a:d181/1282c19:dd:d9:dd:c25:c25a:d00a:d181
1312c19:dd:d9:dd:c25:c25a:d00a:d182/1282c19:dd:d9:dd:c25:c25a:d00a:d182
1322c19:dd:d9:dd:c25:c25a:d00a:d183/1282c19:dd:d9:dd:c25:c25a:d00a:d183
1332c19:dd:d9:dd:c25:c25a:d00a:d184/1282c19:dd:d9:dd:c25:c25a:d00a:d184
1342c19:dd:d9:dd:c25:c25a:d00a:d185/1282c19:dd:d9:dd:c25:c25a:d00a:d185
1352c19:dd:d9:dd:c25:c25a:d00a:d186/1282c19:dd:d9:dd:c25:c25a:d00a:d186
1362c19:dd:d9:dd:c25:c25a:d00a:d187/1282c19:dd:d9:dd:c25:c25a:d00a:d187
1372c19:dd:d9:dd:c25:c25a:d00a:d188/1282c19:dd:d9:dd:c25:c25a:d00a:d188
1382c19:dd:d9:dd:c25:c25a:d00a:d189/1282c19:dd:d9:dd:c25:c25a:d00a:d189
1392c19:dd:d9:dd:c25:c25a:d00a:d18a/1282c19:dd:d9:dd:c25:c25a:d00a:d18a
1402c19:dd:d9:dd:c25:c25a:d00a:d18b/1282c19:dd:d9:dd:c25:c25a:d00a:d18b
1412c19:dd:d9:dd:c25:c25a:d00a:d18c/1282c19:dd:d9:dd:c25:c25a:d00a:d18c
1422c19:dd:d9:dd:c25:c25a:d00a:d18d/1282c19:dd:d9:dd:c25:c25a:d00a:d18d
1432c19:dd:d9:dd:c25:c25a:d00a:d18e/1282c19:dd:d9:dd:c25:c25a:d00a:d18e
1442c19:dd:d9:dd:c25:c25a:d00a:d18f/1282c19:dd:d9:dd:c25:c25a:d00a:d18f
1452c19:dd:d9:dd:c25:c25a:d00a:d190/1282c19:dd:d9:dd:c25:c25a:d00a:d190
1462c19:dd:d9:dd:c25:c25a:d00a:d191/1282c19:dd:d9:dd:c25:c25a:d00a:d191
1472c19:dd:d9:dd:c25:c25a:d00a:d192/1282c19:dd:d9:dd:c25:c25a:d00a:d192
1482c19:dd:d9:dd:c25:c25a:d00a:d193/1282c19:dd:d9:dd:c25:c25a:d00a:d193
1492c19:dd:d9:dd:c25:c25a:d00a:d194/1282c19:dd:d9:dd:c25:c25a:d00a:d194
1502c19:dd:d9:dd:c25:c25a:d00a:d195/1282c19:dd:d9:dd:c25:c25a:d00a:d195
1512c19:dd:d9:dd:c25:c25a:d00a:d196/1282c19:dd:d9:dd:c25:c25a:d00a:d196
1522c19:dd:d9:dd:c25:c25a:d00a:d197/1282c19:dd:d9:dd:c25:c25a:d00a:d197
1532c19:dd:d9:dd:c25:c25a:d00a:d198/1282c19:dd:d9:dd:c25:c25a:d00a:d198
1542c19:dd:d9:dd:c25:c25a:d00a:d199/1282c19:dd:d9:dd:c25:c25a:d00a:d199
1552c19:dd:d9:dd:c25:c25a:d00a:d19a/1282c19:dd:d9:dd:c25:c25a:d00a:d19a
1562c19:dd:d9:dd:c25:c25a:d00a:d19b/1282c19:dd:d9:dd:c25:c25a:d00a:d19b
1572c19:dd:d9:dd:c25:c25a:d00a:d19c/1282c19:dd:d9:dd:c25:c25a:d00a:d19c
1582c19:dd:d9:dd:c25:c25a:d00a:d19d/1282c19:dd:d9:dd:c25:c25a:d00a:d19d
1592c19:dd:d9:dd:c25:c25a:d00a:d19e/1282c19:dd:d9:dd:c25:c25a:d00a:d19e
1602c19:dd:d9:dd:c25:c25a:d00a:d19f/1282c19:dd:d9:dd:c25:c25a:d00a:d19f
1612c19:dd:d9:dd:c25:c25a:d00a:d1a0/1282c19:dd:d9:dd:c25:c25a:d00a:d1a0
1622c19:dd:d9:dd:c25:c25a:d00a:d1a1/1282c19:dd:d9:dd:c25:c25a:d00a:d1a1
1632c19:dd:d9:dd:c25:c25a:d00a:d1a2/1282c19:dd:d9:dd:c25:c25a:d00a:d1a2
1642c19:dd:d9:dd:c25:c25a:d00a:d1a3/1282c19:dd:d9:dd:c25:c25a:d00a:d1a3
1652c19:dd:d9:dd:c25:c25a:d00a:d1a4/1282c19:dd:d9:dd:c25:c25a:d00a:d1a4
1662c19:dd:d9:dd:c25:c25a:d00a:d1a5/1282c19:dd:d9:dd:c25:c25a:d00a:d1a5
1672c19:dd:d9:dd:c25:c25a:d00a:d1a6/1282c19:dd:d9:dd:c25:c25a:d00a:d1a6
1682c19:dd:d9:dd:c25:c25a:d00a:d1a7/1282c19:dd:d9:dd:c25:c25a:d00a:d1a7
1692c19:dd:d9:dd:c25:c25a:d00a:d1a8/1282c19:dd:d9:dd:c25:c25a:d00a:d1a8
1702c19:dd:d9:dd:c25:c25a:d00a:d1a9/1282c19:dd:d9:dd:c25:c25a:d00a:d1a9
1712c19:dd:d9:dd:c25:c25a:d00a:d1aa/1282c19:dd:d9:dd:c25:c25a:d00a:d1aa
1722c19:dd:d9:dd:c25:c25a:d00a:d1ab/1282c19:dd:d9:dd:c25:c25a:d00a:d1ab
1732c19:dd:d9:dd:c25:c25a:d00a:d1ac/1282c19:dd:d9:dd:c25:c25a:d00a:d1ac
1742c19:dd:d9:dd:c25:c25a:d00a:d1ad/1282c19:dd:d9:dd:c25:c25a:d00a:d1ad
1752c19:dd:d9:dd:c25:c25a:d00a:d1ae/1282c19:dd:d9:dd:c25:c25a:d00a:d1ae
1762c19:dd:d9:dd:c25:c25a:d00a:d1af/1282c19:dd:d9:dd:c25:c25a:d00a:d1af
1772c19:dd:d9:dd:c25:c25a:d00a:d1b0/1282c19:dd:d9:dd:c25:c25a:d00a:d1b0
1782c19:dd:d9:dd:c25:c25a:d00a:d1b1/1282c19:dd:d9:dd:c25:c25a:d00a:d1b1
1792c19:dd:d9:dd:c25:c25a:d00a:d1b2/1282c19:dd:d9:dd:c25:c25a:d00a:d1b2
1802c19:dd:d9:dd:c25:c25a:d00a:d1b3/1282c19:dd:d9:dd:c25:c25a:d00a:d1b3
1812c19:dd:d9:dd:c25:c25a:d00a:d1b4/1282c19:dd:d9:dd:c25:c25a:d00a:d1b4
1822c19:dd:d9:dd:c25:c25a:d00a:d1b5/1282c19:dd:d9:dd:c25:c25a:d00a:d1b5
1832c19:dd:d9:dd:c25:c25a:d00a:d1b6/1282c19:dd:d9:dd:c25:c25a:d00a:d1b6
1842c19:dd:d9:dd:c25:c25a:d00a:d1b7/1282c19:dd:d9:dd:c25:c25a:d00a:d1b7
1852c19:dd:d9:dd:c25:c25a:d00a:d1b8/1282c19:dd:d9:dd:c25:c25a:d00a:d1b8
1862c19:dd:d9:dd:c25:c25a:d00a:d1b9/1282c19:dd:d9:dd:c25:c25a:d00a:d1b9
1872c19:dd:d9:dd:c25:c25a:d00a:d1ba/1282c19:dd:d9:dd:c25:c25a:d00a:d1ba
1882c19:dd:d9:dd:c25:c25a:d00a:d1bb/1282c19:dd:d9:dd:c25:c25a:d00a:d1bb
1892c19:dd:d9:dd:c25:c25a:d00a:d1bc/1282c19:dd:d9:dd:c25:c25a:d00a:d1bc
1902c19:dd:d9:dd:c25:c25a:d00a:d1bd/1282c19:dd:d9:dd:c25:c25a:d00a:d1bd
1912c19:dd:d9:dd:c25:c25a:d00a:d1be/1282c19:dd:d9:dd:c25:c25a:d00a:d1be
1922c19:dd:d9:dd:c25:c25a:d00a:d1bf/1282c19:dd:d9:dd:c25:c25a:d00a:d1bf
1932c19:dd:d9:dd:c25:c25a:d00a:d1c0/1282c19:dd:d9:dd:c25:c25a:d00a:d1c0
1942c19:dd:d9:dd:c25:c25a:d00a:d1c1/1282c19:dd:d9:dd:c25:c25a:d00a:d1c1
1952c19:dd:d9:dd:c25:c25a:d00a:d1c2/1282c19:dd:d9:dd:c25:c25a:d00a:d1c2
1962c19:dd:d9:dd:c25:c25a:d00a:d1c3/1282c19:dd:d9:dd:c25:c25a:d00a:d1c3
1972c19:dd:d9:dd:c25:c25a:d00a:d1c4/1282c19:dd:d9:dd:c25:c25a:d00a:d1c4
1982c19:dd:d9:dd:c25:c25a:d00a:d1c5/1282c19:dd:d9:dd:c25:c25a:d00a:d1c5
1992c19:dd:d9:dd:c25:c25a:d00a:d1c6/1282c19:dd:d9:dd:c25:c25a:d00a:d1c6
2002c19:dd:d9:dd:c25:c25a:d00a:d1c7/1282c19:dd:d9:dd:c25:c25a:d00a:d1c7
2012c19:dd:d9:dd:c25:c25a:d00a:d1c8/1282c19:dd:d9:dd:c25:c25a:d00a:d1c8
2022c19:dd:d9:dd:c25:c25a:d00a:d1c9/1282c19:dd:d9:dd:c25:c25a:d00a:d1c9
2032c19:dd:d9:dd:c25:c25a:d00a:d1ca/1282c19:dd:d9:dd:c25:c25a:d00a:d1ca
2042c19:dd:d9:dd:c25:c25a:d00a:d1cb/1282c19:dd:d9:dd:c25:c25a:d00a:d1cb
2052c19:dd:d9:dd:c25:c25a:d00a:d1cc/1282c19:dd:d9:dd:c25:c25a:d00a:d1cc
2062c19:dd:d9:dd:c25:c25a:d00a:d1cd/1282c19:dd:d9:dd:c25:c25a:d00a:d1cd
2072c19:dd:d9:dd:c25:c25a:d00a:d1ce/1282c19:dd:d9:dd:c25:c25a:d00a:d1ce
2082c19:dd:d9:dd:c25:c25a:d00a:d1cf/1282c19:dd:d9:dd:c25:c25a:d00a:d1cf
2092c19:dd:d9:dd:c25:c25a:d00a:d1d0/1282c19:dd:d9:dd:c25:c25a:d00a:d1d0
2102c19:dd:d9:dd:c25:c25a:d00a:d1d1/1282c19:dd:d9:dd:c25:c25a:d00a:d1d1
2112c19:dd:d9:dd:c25:c25a:d00a:d1d2/1282c19:dd:d9:dd:c25:c25a:d00a:d1d2
2122c19:dd:d9:dd:c25:c25a:d00a:d1d3/1282c19:dd:d9:dd:c25:c25a:d00a:d1d3
2132c19:dd:d9:dd:c25:c25a:d00a:d1d4/1282c19:dd:d9:dd:c25:c25a:d00a:d1d4
2142c19:dd:d9:dd:c25:c25a:d00a:d1d5/1282c19:dd:d9:dd:c25:c25a:d00a:d1d5
2152c19:dd:d9:dd:c25:c25a:d00a:d1d6/1282c19:dd:d9:dd:c25:c25a:d00a:d1d6
2162c19:dd:d9:dd:c25:c25a:d00a:d1d7/1282c19:dd:d9:dd:c25:c25a:d00a:d1d7
2172c19:dd:d9:dd:c25:c25a:d00a:d1d8/1282c19:dd:d9:dd:c25:c25a:d00a:d1d8
2182c19:dd:d9:dd:c25:c25a:d00a:d1d9/1282c19:dd:d9:dd:c25:c25a:d00a:d1d9
2192c19:dd:d9:dd:c25:c25a:d00a:d1da/1282c19:dd:d9:dd:c25:c25a:d00a:d1da
2202c19:dd:d9:dd:c25:c25a:d00a:d1db/1282c19:dd:d9:dd:c25:c25a:d00a:d1db
2212c19:dd:d9:dd:c25:c25a:d00a:d1dc/1282c19:dd:d9:dd:c25:c25a:d00a:d1dc
2222c19:dd:d9:dd:c25:c25a:d00a:d1dd/1282c19:dd:d9:dd:c25:c25a:d00a:d1dd
2232c19:dd:d9:dd:c25:c25a:d00a:d1de/1282c19:dd:d9:dd:c25:c25a:d00a:d1de
2242c19:dd:d9:dd:c25:c25a:d00a:d1df/1282c19:dd:d9:dd:c25:c25a:d00a:d1df
2252c19:dd:d9:dd:c25:c25a:d00a:d1e0/1282c19:dd:d9:dd:c25:c25a:d00a:d1e0
2262c19:dd:d9:dd:c25:c25a:d00a:d1e1/1282c19:dd:d9:dd:c25:c25a:d00a:d1e1
2272c19:dd:d9:dd:c25:c25a:d00a:d1e2/1282c19:dd:d9:dd:c25:c25a:d00a:d1e2
2282c19:dd:d9:dd:c25:c25a:d00a:d1e3/1282c19:dd:d9:dd:c25:c25a:d00a:d1e3
2292c19:dd:d9:dd:c25:c25a:d00a:d1e4/1282c19:dd:d9:dd:c25:c25a:d00a:d1e4
2302c19:dd:d9:dd:c25:c25a:d00a:d1e5/1282c19:dd:d9:dd:c25:c25a:d00a:d1e5
2312c19:dd:d9:dd:c25:c25a:d00a:d1e6/1282c19:dd:d9:dd:c25:c25a:d00a:d1e6
2322c19:dd:d9:dd:c25:c25a:d00a:d1e7/1282c19:dd:d9:dd:c25:c25a:d00a:d1e7
2332c19:dd:d9:dd:c25:c25a:d00a:d1e8/1282c19:dd:d9:dd:c25:c25a:d00a:d1e8
2342c19:dd:d9:dd:c25:c25a:d00a:d1e9/1282c19:dd:d9:dd:c25:c25a:d00a:d1e9
2352c19:dd:d9:dd:c25:c25a:d00a:d1ea/1282c19:dd:d9:dd:c25:c25a:d00a:d1ea
2362c19:dd:d9:dd:c25:c25a:d00a:d1eb/1282c19:dd:d9:dd:c25:c25a:d00a:d1eb
2372c19:dd:d9:dd:c25:c25a:d00a:d1ec/1282c19:dd:d9:dd:c25:c25a:d00a:d1ec
2382c19:dd:d9:dd:c25:c25a:d00a:d1ed/1282c19:dd:d9:dd:c25:c25a:d00a:d1ed
2392c19:dd:d9:dd:c25:c25a:d00a:d1ee/1282c19:dd:d9:dd:c25:c25a:d00a:d1ee
2402c19:dd:d9:dd:c25:c25a:d00a:d1ef/1282c19:dd:d9:dd:c25:c25a:d00a:d1ef
2412c19:dd:d9:dd:c25:c25a:d00a:d1f0/1282c19:dd:d9:dd:c25:c25a:d00a:d1f0
2422c19:dd:d9:dd:c25:c25a:d00a:d1f1/1282c19:dd:d9:dd:c25:c25a:d00a:d1f1
2432c19:dd:d9:dd:c25:c25a:d00a:d1f2/1282c19:dd:d9:dd:c25:c25a:d00a:d1f2
2442c19:dd:d9:dd:c25:c25a:d00a:d1f3/1282c19:dd:d9:dd:c25:c25a:d00a:d1f3
2452c19:dd:d9:dd:c25:c25a:d00a:d1f4/1282c19:dd:d9:dd:c25:c25a:d00a:d1f4
2462c19:dd:d9:dd:c25:c25a:d00a:d1f5/1282c19:dd:d9:dd:c25:c25a:d00a:d1f5
2472c19:dd:d9:dd:c25:c25a:d00a:d1f6/1282c19:dd:d9:dd:c25:c25a:d00a:d1f6
2482c19:dd:d9:dd:c25:c25a:d00a:d1f7/1282c19:dd:d9:dd:c25:c25a:d00a:d1f7
2492c19:dd:d9:dd:c25:c25a:d00a:d1f8/1282c19:dd:d9:dd:c25:c25a:d00a:d1f8
2502c19:dd:d9:dd:c25:c25a:d00a:d1f9/1282c19:dd:d9:dd:c25:c25a:d00a:d1f9
2512c19:dd:d9:dd:c25:c25a:d00a:d1fa/1282c19:dd:d9:dd:c25:c25a:d00a:d1fa
2522c19:dd:d9:dd:c25:c25a:d00a:d1fb/1282c19:dd:d9:dd:c25:c25a:d00a:d1fb
2532c19:dd:d9:dd:c25:c25a:d00a:d1fc/1282c19:dd:d9:dd:c25:c25a:d00a:d1fc
2542c19:dd:d9:dd:c25:c25a:d00a:d1fd/1282c19:dd:d9:dd:c25:c25a:d00a:d1fd
2552c19:dd:d9:dd:c25:c25a:d00a:d1fe/1282c19:dd:d9:dd:c25:c25a:d00a:d1fe
2562c19:dd:d9:dd:c25:c25a:d00a:d1ff/1282c19:dd:d9:dd:c25:c25a:d00a:d1ff

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.