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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:d00a:b100/120
First address
2c19:dd:d9:dd:c25:c25:d00a:b100
Last address
2c19:dd:d9:dd:c25:c25:d00a:b1ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d00a:b100
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
1.b.a.0.0.d.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:d00a:b100/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d00a:b100/1282c19:dd:d9:dd:c25:c25:d00a:b100
22c19:dd:d9:dd:c25:c25:d00a:b101/1282c19:dd:d9:dd:c25:c25:d00a:b101
32c19:dd:d9:dd:c25:c25:d00a:b102/1282c19:dd:d9:dd:c25:c25:d00a:b102
42c19:dd:d9:dd:c25:c25:d00a:b103/1282c19:dd:d9:dd:c25:c25:d00a:b103
52c19:dd:d9:dd:c25:c25:d00a:b104/1282c19:dd:d9:dd:c25:c25:d00a:b104
62c19:dd:d9:dd:c25:c25:d00a:b105/1282c19:dd:d9:dd:c25:c25:d00a:b105
72c19:dd:d9:dd:c25:c25:d00a:b106/1282c19:dd:d9:dd:c25:c25:d00a:b106
82c19:dd:d9:dd:c25:c25:d00a:b107/1282c19:dd:d9:dd:c25:c25:d00a:b107
92c19:dd:d9:dd:c25:c25:d00a:b108/1282c19:dd:d9:dd:c25:c25:d00a:b108
102c19:dd:d9:dd:c25:c25:d00a:b109/1282c19:dd:d9:dd:c25:c25:d00a:b109
112c19:dd:d9:dd:c25:c25:d00a:b10a/1282c19:dd:d9:dd:c25:c25:d00a:b10a
122c19:dd:d9:dd:c25:c25:d00a:b10b/1282c19:dd:d9:dd:c25:c25:d00a:b10b
132c19:dd:d9:dd:c25:c25:d00a:b10c/1282c19:dd:d9:dd:c25:c25:d00a:b10c
142c19:dd:d9:dd:c25:c25:d00a:b10d/1282c19:dd:d9:dd:c25:c25:d00a:b10d
152c19:dd:d9:dd:c25:c25:d00a:b10e/1282c19:dd:d9:dd:c25:c25:d00a:b10e
162c19:dd:d9:dd:c25:c25:d00a:b10f/1282c19:dd:d9:dd:c25:c25:d00a:b10f
172c19:dd:d9:dd:c25:c25:d00a:b110/1282c19:dd:d9:dd:c25:c25:d00a:b110
182c19:dd:d9:dd:c25:c25:d00a:b111/1282c19:dd:d9:dd:c25:c25:d00a:b111
192c19:dd:d9:dd:c25:c25:d00a:b112/1282c19:dd:d9:dd:c25:c25:d00a:b112
202c19:dd:d9:dd:c25:c25:d00a:b113/1282c19:dd:d9:dd:c25:c25:d00a:b113
212c19:dd:d9:dd:c25:c25:d00a:b114/1282c19:dd:d9:dd:c25:c25:d00a:b114
222c19:dd:d9:dd:c25:c25:d00a:b115/1282c19:dd:d9:dd:c25:c25:d00a:b115
232c19:dd:d9:dd:c25:c25:d00a:b116/1282c19:dd:d9:dd:c25:c25:d00a:b116
242c19:dd:d9:dd:c25:c25:d00a:b117/1282c19:dd:d9:dd:c25:c25:d00a:b117
252c19:dd:d9:dd:c25:c25:d00a:b118/1282c19:dd:d9:dd:c25:c25:d00a:b118
262c19:dd:d9:dd:c25:c25:d00a:b119/1282c19:dd:d9:dd:c25:c25:d00a:b119
272c19:dd:d9:dd:c25:c25:d00a:b11a/1282c19:dd:d9:dd:c25:c25:d00a:b11a
282c19:dd:d9:dd:c25:c25:d00a:b11b/1282c19:dd:d9:dd:c25:c25:d00a:b11b
292c19:dd:d9:dd:c25:c25:d00a:b11c/1282c19:dd:d9:dd:c25:c25:d00a:b11c
302c19:dd:d9:dd:c25:c25:d00a:b11d/1282c19:dd:d9:dd:c25:c25:d00a:b11d
312c19:dd:d9:dd:c25:c25:d00a:b11e/1282c19:dd:d9:dd:c25:c25:d00a:b11e
322c19:dd:d9:dd:c25:c25:d00a:b11f/1282c19:dd:d9:dd:c25:c25:d00a:b11f
332c19:dd:d9:dd:c25:c25:d00a:b120/1282c19:dd:d9:dd:c25:c25:d00a:b120
342c19:dd:d9:dd:c25:c25:d00a:b121/1282c19:dd:d9:dd:c25:c25:d00a:b121
352c19:dd:d9:dd:c25:c25:d00a:b122/1282c19:dd:d9:dd:c25:c25:d00a:b122
362c19:dd:d9:dd:c25:c25:d00a:b123/1282c19:dd:d9:dd:c25:c25:d00a:b123
372c19:dd:d9:dd:c25:c25:d00a:b124/1282c19:dd:d9:dd:c25:c25:d00a:b124
382c19:dd:d9:dd:c25:c25:d00a:b125/1282c19:dd:d9:dd:c25:c25:d00a:b125
392c19:dd:d9:dd:c25:c25:d00a:b126/1282c19:dd:d9:dd:c25:c25:d00a:b126
402c19:dd:d9:dd:c25:c25:d00a:b127/1282c19:dd:d9:dd:c25:c25:d00a:b127
412c19:dd:d9:dd:c25:c25:d00a:b128/1282c19:dd:d9:dd:c25:c25:d00a:b128
422c19:dd:d9:dd:c25:c25:d00a:b129/1282c19:dd:d9:dd:c25:c25:d00a:b129
432c19:dd:d9:dd:c25:c25:d00a:b12a/1282c19:dd:d9:dd:c25:c25:d00a:b12a
442c19:dd:d9:dd:c25:c25:d00a:b12b/1282c19:dd:d9:dd:c25:c25:d00a:b12b
452c19:dd:d9:dd:c25:c25:d00a:b12c/1282c19:dd:d9:dd:c25:c25:d00a:b12c
462c19:dd:d9:dd:c25:c25:d00a:b12d/1282c19:dd:d9:dd:c25:c25:d00a:b12d
472c19:dd:d9:dd:c25:c25:d00a:b12e/1282c19:dd:d9:dd:c25:c25:d00a:b12e
482c19:dd:d9:dd:c25:c25:d00a:b12f/1282c19:dd:d9:dd:c25:c25:d00a:b12f
492c19:dd:d9:dd:c25:c25:d00a:b130/1282c19:dd:d9:dd:c25:c25:d00a:b130
502c19:dd:d9:dd:c25:c25:d00a:b131/1282c19:dd:d9:dd:c25:c25:d00a:b131
512c19:dd:d9:dd:c25:c25:d00a:b132/1282c19:dd:d9:dd:c25:c25:d00a:b132
522c19:dd:d9:dd:c25:c25:d00a:b133/1282c19:dd:d9:dd:c25:c25:d00a:b133
532c19:dd:d9:dd:c25:c25:d00a:b134/1282c19:dd:d9:dd:c25:c25:d00a:b134
542c19:dd:d9:dd:c25:c25:d00a:b135/1282c19:dd:d9:dd:c25:c25:d00a:b135
552c19:dd:d9:dd:c25:c25:d00a:b136/1282c19:dd:d9:dd:c25:c25:d00a:b136
562c19:dd:d9:dd:c25:c25:d00a:b137/1282c19:dd:d9:dd:c25:c25:d00a:b137
572c19:dd:d9:dd:c25:c25:d00a:b138/1282c19:dd:d9:dd:c25:c25:d00a:b138
582c19:dd:d9:dd:c25:c25:d00a:b139/1282c19:dd:d9:dd:c25:c25:d00a:b139
592c19:dd:d9:dd:c25:c25:d00a:b13a/1282c19:dd:d9:dd:c25:c25:d00a:b13a
602c19:dd:d9:dd:c25:c25:d00a:b13b/1282c19:dd:d9:dd:c25:c25:d00a:b13b
612c19:dd:d9:dd:c25:c25:d00a:b13c/1282c19:dd:d9:dd:c25:c25:d00a:b13c
622c19:dd:d9:dd:c25:c25:d00a:b13d/1282c19:dd:d9:dd:c25:c25:d00a:b13d
632c19:dd:d9:dd:c25:c25:d00a:b13e/1282c19:dd:d9:dd:c25:c25:d00a:b13e
642c19:dd:d9:dd:c25:c25:d00a:b13f/1282c19:dd:d9:dd:c25:c25:d00a:b13f
652c19:dd:d9:dd:c25:c25:d00a:b140/1282c19:dd:d9:dd:c25:c25:d00a:b140
662c19:dd:d9:dd:c25:c25:d00a:b141/1282c19:dd:d9:dd:c25:c25:d00a:b141
672c19:dd:d9:dd:c25:c25:d00a:b142/1282c19:dd:d9:dd:c25:c25:d00a:b142
682c19:dd:d9:dd:c25:c25:d00a:b143/1282c19:dd:d9:dd:c25:c25:d00a:b143
692c19:dd:d9:dd:c25:c25:d00a:b144/1282c19:dd:d9:dd:c25:c25:d00a:b144
702c19:dd:d9:dd:c25:c25:d00a:b145/1282c19:dd:d9:dd:c25:c25:d00a:b145
712c19:dd:d9:dd:c25:c25:d00a:b146/1282c19:dd:d9:dd:c25:c25:d00a:b146
722c19:dd:d9:dd:c25:c25:d00a:b147/1282c19:dd:d9:dd:c25:c25:d00a:b147
732c19:dd:d9:dd:c25:c25:d00a:b148/1282c19:dd:d9:dd:c25:c25:d00a:b148
742c19:dd:d9:dd:c25:c25:d00a:b149/1282c19:dd:d9:dd:c25:c25:d00a:b149
752c19:dd:d9:dd:c25:c25:d00a:b14a/1282c19:dd:d9:dd:c25:c25:d00a:b14a
762c19:dd:d9:dd:c25:c25:d00a:b14b/1282c19:dd:d9:dd:c25:c25:d00a:b14b
772c19:dd:d9:dd:c25:c25:d00a:b14c/1282c19:dd:d9:dd:c25:c25:d00a:b14c
782c19:dd:d9:dd:c25:c25:d00a:b14d/1282c19:dd:d9:dd:c25:c25:d00a:b14d
792c19:dd:d9:dd:c25:c25:d00a:b14e/1282c19:dd:d9:dd:c25:c25:d00a:b14e
802c19:dd:d9:dd:c25:c25:d00a:b14f/1282c19:dd:d9:dd:c25:c25:d00a:b14f
812c19:dd:d9:dd:c25:c25:d00a:b150/1282c19:dd:d9:dd:c25:c25:d00a:b150
822c19:dd:d9:dd:c25:c25:d00a:b151/1282c19:dd:d9:dd:c25:c25:d00a:b151
832c19:dd:d9:dd:c25:c25:d00a:b152/1282c19:dd:d9:dd:c25:c25:d00a:b152
842c19:dd:d9:dd:c25:c25:d00a:b153/1282c19:dd:d9:dd:c25:c25:d00a:b153
852c19:dd:d9:dd:c25:c25:d00a:b154/1282c19:dd:d9:dd:c25:c25:d00a:b154
862c19:dd:d9:dd:c25:c25:d00a:b155/1282c19:dd:d9:dd:c25:c25:d00a:b155
872c19:dd:d9:dd:c25:c25:d00a:b156/1282c19:dd:d9:dd:c25:c25:d00a:b156
882c19:dd:d9:dd:c25:c25:d00a:b157/1282c19:dd:d9:dd:c25:c25:d00a:b157
892c19:dd:d9:dd:c25:c25:d00a:b158/1282c19:dd:d9:dd:c25:c25:d00a:b158
902c19:dd:d9:dd:c25:c25:d00a:b159/1282c19:dd:d9:dd:c25:c25:d00a:b159
912c19:dd:d9:dd:c25:c25:d00a:b15a/1282c19:dd:d9:dd:c25:c25:d00a:b15a
922c19:dd:d9:dd:c25:c25:d00a:b15b/1282c19:dd:d9:dd:c25:c25:d00a:b15b
932c19:dd:d9:dd:c25:c25:d00a:b15c/1282c19:dd:d9:dd:c25:c25:d00a:b15c
942c19:dd:d9:dd:c25:c25:d00a:b15d/1282c19:dd:d9:dd:c25:c25:d00a:b15d
952c19:dd:d9:dd:c25:c25:d00a:b15e/1282c19:dd:d9:dd:c25:c25:d00a:b15e
962c19:dd:d9:dd:c25:c25:d00a:b15f/1282c19:dd:d9:dd:c25:c25:d00a:b15f
972c19:dd:d9:dd:c25:c25:d00a:b160/1282c19:dd:d9:dd:c25:c25:d00a:b160
982c19:dd:d9:dd:c25:c25:d00a:b161/1282c19:dd:d9:dd:c25:c25:d00a:b161
992c19:dd:d9:dd:c25:c25:d00a:b162/1282c19:dd:d9:dd:c25:c25:d00a:b162
1002c19:dd:d9:dd:c25:c25:d00a:b163/1282c19:dd:d9:dd:c25:c25:d00a:b163
1012c19:dd:d9:dd:c25:c25:d00a:b164/1282c19:dd:d9:dd:c25:c25:d00a:b164
1022c19:dd:d9:dd:c25:c25:d00a:b165/1282c19:dd:d9:dd:c25:c25:d00a:b165
1032c19:dd:d9:dd:c25:c25:d00a:b166/1282c19:dd:d9:dd:c25:c25:d00a:b166
1042c19:dd:d9:dd:c25:c25:d00a:b167/1282c19:dd:d9:dd:c25:c25:d00a:b167
1052c19:dd:d9:dd:c25:c25:d00a:b168/1282c19:dd:d9:dd:c25:c25:d00a:b168
1062c19:dd:d9:dd:c25:c25:d00a:b169/1282c19:dd:d9:dd:c25:c25:d00a:b169
1072c19:dd:d9:dd:c25:c25:d00a:b16a/1282c19:dd:d9:dd:c25:c25:d00a:b16a
1082c19:dd:d9:dd:c25:c25:d00a:b16b/1282c19:dd:d9:dd:c25:c25:d00a:b16b
1092c19:dd:d9:dd:c25:c25:d00a:b16c/1282c19:dd:d9:dd:c25:c25:d00a:b16c
1102c19:dd:d9:dd:c25:c25:d00a:b16d/1282c19:dd:d9:dd:c25:c25:d00a:b16d
1112c19:dd:d9:dd:c25:c25:d00a:b16e/1282c19:dd:d9:dd:c25:c25:d00a:b16e
1122c19:dd:d9:dd:c25:c25:d00a:b16f/1282c19:dd:d9:dd:c25:c25:d00a:b16f
1132c19:dd:d9:dd:c25:c25:d00a:b170/1282c19:dd:d9:dd:c25:c25:d00a:b170
1142c19:dd:d9:dd:c25:c25:d00a:b171/1282c19:dd:d9:dd:c25:c25:d00a:b171
1152c19:dd:d9:dd:c25:c25:d00a:b172/1282c19:dd:d9:dd:c25:c25:d00a:b172
1162c19:dd:d9:dd:c25:c25:d00a:b173/1282c19:dd:d9:dd:c25:c25:d00a:b173
1172c19:dd:d9:dd:c25:c25:d00a:b174/1282c19:dd:d9:dd:c25:c25:d00a:b174
1182c19:dd:d9:dd:c25:c25:d00a:b175/1282c19:dd:d9:dd:c25:c25:d00a:b175
1192c19:dd:d9:dd:c25:c25:d00a:b176/1282c19:dd:d9:dd:c25:c25:d00a:b176
1202c19:dd:d9:dd:c25:c25:d00a:b177/1282c19:dd:d9:dd:c25:c25:d00a:b177
1212c19:dd:d9:dd:c25:c25:d00a:b178/1282c19:dd:d9:dd:c25:c25:d00a:b178
1222c19:dd:d9:dd:c25:c25:d00a:b179/1282c19:dd:d9:dd:c25:c25:d00a:b179
1232c19:dd:d9:dd:c25:c25:d00a:b17a/1282c19:dd:d9:dd:c25:c25:d00a:b17a
1242c19:dd:d9:dd:c25:c25:d00a:b17b/1282c19:dd:d9:dd:c25:c25:d00a:b17b
1252c19:dd:d9:dd:c25:c25:d00a:b17c/1282c19:dd:d9:dd:c25:c25:d00a:b17c
1262c19:dd:d9:dd:c25:c25:d00a:b17d/1282c19:dd:d9:dd:c25:c25:d00a:b17d
1272c19:dd:d9:dd:c25:c25:d00a:b17e/1282c19:dd:d9:dd:c25:c25:d00a:b17e
1282c19:dd:d9:dd:c25:c25:d00a:b17f/1282c19:dd:d9:dd:c25:c25:d00a:b17f
1292c19:dd:d9:dd:c25:c25:d00a:b180/1282c19:dd:d9:dd:c25:c25:d00a:b180
1302c19:dd:d9:dd:c25:c25:d00a:b181/1282c19:dd:d9:dd:c25:c25:d00a:b181
1312c19:dd:d9:dd:c25:c25:d00a:b182/1282c19:dd:d9:dd:c25:c25:d00a:b182
1322c19:dd:d9:dd:c25:c25:d00a:b183/1282c19:dd:d9:dd:c25:c25:d00a:b183
1332c19:dd:d9:dd:c25:c25:d00a:b184/1282c19:dd:d9:dd:c25:c25:d00a:b184
1342c19:dd:d9:dd:c25:c25:d00a:b185/1282c19:dd:d9:dd:c25:c25:d00a:b185
1352c19:dd:d9:dd:c25:c25:d00a:b186/1282c19:dd:d9:dd:c25:c25:d00a:b186
1362c19:dd:d9:dd:c25:c25:d00a:b187/1282c19:dd:d9:dd:c25:c25:d00a:b187
1372c19:dd:d9:dd:c25:c25:d00a:b188/1282c19:dd:d9:dd:c25:c25:d00a:b188
1382c19:dd:d9:dd:c25:c25:d00a:b189/1282c19:dd:d9:dd:c25:c25:d00a:b189
1392c19:dd:d9:dd:c25:c25:d00a:b18a/1282c19:dd:d9:dd:c25:c25:d00a:b18a
1402c19:dd:d9:dd:c25:c25:d00a:b18b/1282c19:dd:d9:dd:c25:c25:d00a:b18b
1412c19:dd:d9:dd:c25:c25:d00a:b18c/1282c19:dd:d9:dd:c25:c25:d00a:b18c
1422c19:dd:d9:dd:c25:c25:d00a:b18d/1282c19:dd:d9:dd:c25:c25:d00a:b18d
1432c19:dd:d9:dd:c25:c25:d00a:b18e/1282c19:dd:d9:dd:c25:c25:d00a:b18e
1442c19:dd:d9:dd:c25:c25:d00a:b18f/1282c19:dd:d9:dd:c25:c25:d00a:b18f
1452c19:dd:d9:dd:c25:c25:d00a:b190/1282c19:dd:d9:dd:c25:c25:d00a:b190
1462c19:dd:d9:dd:c25:c25:d00a:b191/1282c19:dd:d9:dd:c25:c25:d00a:b191
1472c19:dd:d9:dd:c25:c25:d00a:b192/1282c19:dd:d9:dd:c25:c25:d00a:b192
1482c19:dd:d9:dd:c25:c25:d00a:b193/1282c19:dd:d9:dd:c25:c25:d00a:b193
1492c19:dd:d9:dd:c25:c25:d00a:b194/1282c19:dd:d9:dd:c25:c25:d00a:b194
1502c19:dd:d9:dd:c25:c25:d00a:b195/1282c19:dd:d9:dd:c25:c25:d00a:b195
1512c19:dd:d9:dd:c25:c25:d00a:b196/1282c19:dd:d9:dd:c25:c25:d00a:b196
1522c19:dd:d9:dd:c25:c25:d00a:b197/1282c19:dd:d9:dd:c25:c25:d00a:b197
1532c19:dd:d9:dd:c25:c25:d00a:b198/1282c19:dd:d9:dd:c25:c25:d00a:b198
1542c19:dd:d9:dd:c25:c25:d00a:b199/1282c19:dd:d9:dd:c25:c25:d00a:b199
1552c19:dd:d9:dd:c25:c25:d00a:b19a/1282c19:dd:d9:dd:c25:c25:d00a:b19a
1562c19:dd:d9:dd:c25:c25:d00a:b19b/1282c19:dd:d9:dd:c25:c25:d00a:b19b
1572c19:dd:d9:dd:c25:c25:d00a:b19c/1282c19:dd:d9:dd:c25:c25:d00a:b19c
1582c19:dd:d9:dd:c25:c25:d00a:b19d/1282c19:dd:d9:dd:c25:c25:d00a:b19d
1592c19:dd:d9:dd:c25:c25:d00a:b19e/1282c19:dd:d9:dd:c25:c25:d00a:b19e
1602c19:dd:d9:dd:c25:c25:d00a:b19f/1282c19:dd:d9:dd:c25:c25:d00a:b19f
1612c19:dd:d9:dd:c25:c25:d00a:b1a0/1282c19:dd:d9:dd:c25:c25:d00a:b1a0
1622c19:dd:d9:dd:c25:c25:d00a:b1a1/1282c19:dd:d9:dd:c25:c25:d00a:b1a1
1632c19:dd:d9:dd:c25:c25:d00a:b1a2/1282c19:dd:d9:dd:c25:c25:d00a:b1a2
1642c19:dd:d9:dd:c25:c25:d00a:b1a3/1282c19:dd:d9:dd:c25:c25:d00a:b1a3
1652c19:dd:d9:dd:c25:c25:d00a:b1a4/1282c19:dd:d9:dd:c25:c25:d00a:b1a4
1662c19:dd:d9:dd:c25:c25:d00a:b1a5/1282c19:dd:d9:dd:c25:c25:d00a:b1a5
1672c19:dd:d9:dd:c25:c25:d00a:b1a6/1282c19:dd:d9:dd:c25:c25:d00a:b1a6
1682c19:dd:d9:dd:c25:c25:d00a:b1a7/1282c19:dd:d9:dd:c25:c25:d00a:b1a7
1692c19:dd:d9:dd:c25:c25:d00a:b1a8/1282c19:dd:d9:dd:c25:c25:d00a:b1a8
1702c19:dd:d9:dd:c25:c25:d00a:b1a9/1282c19:dd:d9:dd:c25:c25:d00a:b1a9
1712c19:dd:d9:dd:c25:c25:d00a:b1aa/1282c19:dd:d9:dd:c25:c25:d00a:b1aa
1722c19:dd:d9:dd:c25:c25:d00a:b1ab/1282c19:dd:d9:dd:c25:c25:d00a:b1ab
1732c19:dd:d9:dd:c25:c25:d00a:b1ac/1282c19:dd:d9:dd:c25:c25:d00a:b1ac
1742c19:dd:d9:dd:c25:c25:d00a:b1ad/1282c19:dd:d9:dd:c25:c25:d00a:b1ad
1752c19:dd:d9:dd:c25:c25:d00a:b1ae/1282c19:dd:d9:dd:c25:c25:d00a:b1ae
1762c19:dd:d9:dd:c25:c25:d00a:b1af/1282c19:dd:d9:dd:c25:c25:d00a:b1af
1772c19:dd:d9:dd:c25:c25:d00a:b1b0/1282c19:dd:d9:dd:c25:c25:d00a:b1b0
1782c19:dd:d9:dd:c25:c25:d00a:b1b1/1282c19:dd:d9:dd:c25:c25:d00a:b1b1
1792c19:dd:d9:dd:c25:c25:d00a:b1b2/1282c19:dd:d9:dd:c25:c25:d00a:b1b2
1802c19:dd:d9:dd:c25:c25:d00a:b1b3/1282c19:dd:d9:dd:c25:c25:d00a:b1b3
1812c19:dd:d9:dd:c25:c25:d00a:b1b4/1282c19:dd:d9:dd:c25:c25:d00a:b1b4
1822c19:dd:d9:dd:c25:c25:d00a:b1b5/1282c19:dd:d9:dd:c25:c25:d00a:b1b5
1832c19:dd:d9:dd:c25:c25:d00a:b1b6/1282c19:dd:d9:dd:c25:c25:d00a:b1b6
1842c19:dd:d9:dd:c25:c25:d00a:b1b7/1282c19:dd:d9:dd:c25:c25:d00a:b1b7
1852c19:dd:d9:dd:c25:c25:d00a:b1b8/1282c19:dd:d9:dd:c25:c25:d00a:b1b8
1862c19:dd:d9:dd:c25:c25:d00a:b1b9/1282c19:dd:d9:dd:c25:c25:d00a:b1b9
1872c19:dd:d9:dd:c25:c25:d00a:b1ba/1282c19:dd:d9:dd:c25:c25:d00a:b1ba
1882c19:dd:d9:dd:c25:c25:d00a:b1bb/1282c19:dd:d9:dd:c25:c25:d00a:b1bb
1892c19:dd:d9:dd:c25:c25:d00a:b1bc/1282c19:dd:d9:dd:c25:c25:d00a:b1bc
1902c19:dd:d9:dd:c25:c25:d00a:b1bd/1282c19:dd:d9:dd:c25:c25:d00a:b1bd
1912c19:dd:d9:dd:c25:c25:d00a:b1be/1282c19:dd:d9:dd:c25:c25:d00a:b1be
1922c19:dd:d9:dd:c25:c25:d00a:b1bf/1282c19:dd:d9:dd:c25:c25:d00a:b1bf
1932c19:dd:d9:dd:c25:c25:d00a:b1c0/1282c19:dd:d9:dd:c25:c25:d00a:b1c0
1942c19:dd:d9:dd:c25:c25:d00a:b1c1/1282c19:dd:d9:dd:c25:c25:d00a:b1c1
1952c19:dd:d9:dd:c25:c25:d00a:b1c2/1282c19:dd:d9:dd:c25:c25:d00a:b1c2
1962c19:dd:d9:dd:c25:c25:d00a:b1c3/1282c19:dd:d9:dd:c25:c25:d00a:b1c3
1972c19:dd:d9:dd:c25:c25:d00a:b1c4/1282c19:dd:d9:dd:c25:c25:d00a:b1c4
1982c19:dd:d9:dd:c25:c25:d00a:b1c5/1282c19:dd:d9:dd:c25:c25:d00a:b1c5
1992c19:dd:d9:dd:c25:c25:d00a:b1c6/1282c19:dd:d9:dd:c25:c25:d00a:b1c6
2002c19:dd:d9:dd:c25:c25:d00a:b1c7/1282c19:dd:d9:dd:c25:c25:d00a:b1c7
2012c19:dd:d9:dd:c25:c25:d00a:b1c8/1282c19:dd:d9:dd:c25:c25:d00a:b1c8
2022c19:dd:d9:dd:c25:c25:d00a:b1c9/1282c19:dd:d9:dd:c25:c25:d00a:b1c9
2032c19:dd:d9:dd:c25:c25:d00a:b1ca/1282c19:dd:d9:dd:c25:c25:d00a:b1ca
2042c19:dd:d9:dd:c25:c25:d00a:b1cb/1282c19:dd:d9:dd:c25:c25:d00a:b1cb
2052c19:dd:d9:dd:c25:c25:d00a:b1cc/1282c19:dd:d9:dd:c25:c25:d00a:b1cc
2062c19:dd:d9:dd:c25:c25:d00a:b1cd/1282c19:dd:d9:dd:c25:c25:d00a:b1cd
2072c19:dd:d9:dd:c25:c25:d00a:b1ce/1282c19:dd:d9:dd:c25:c25:d00a:b1ce
2082c19:dd:d9:dd:c25:c25:d00a:b1cf/1282c19:dd:d9:dd:c25:c25:d00a:b1cf
2092c19:dd:d9:dd:c25:c25:d00a:b1d0/1282c19:dd:d9:dd:c25:c25:d00a:b1d0
2102c19:dd:d9:dd:c25:c25:d00a:b1d1/1282c19:dd:d9:dd:c25:c25:d00a:b1d1
2112c19:dd:d9:dd:c25:c25:d00a:b1d2/1282c19:dd:d9:dd:c25:c25:d00a:b1d2
2122c19:dd:d9:dd:c25:c25:d00a:b1d3/1282c19:dd:d9:dd:c25:c25:d00a:b1d3
2132c19:dd:d9:dd:c25:c25:d00a:b1d4/1282c19:dd:d9:dd:c25:c25:d00a:b1d4
2142c19:dd:d9:dd:c25:c25:d00a:b1d5/1282c19:dd:d9:dd:c25:c25:d00a:b1d5
2152c19:dd:d9:dd:c25:c25:d00a:b1d6/1282c19:dd:d9:dd:c25:c25:d00a:b1d6
2162c19:dd:d9:dd:c25:c25:d00a:b1d7/1282c19:dd:d9:dd:c25:c25:d00a:b1d7
2172c19:dd:d9:dd:c25:c25:d00a:b1d8/1282c19:dd:d9:dd:c25:c25:d00a:b1d8
2182c19:dd:d9:dd:c25:c25:d00a:b1d9/1282c19:dd:d9:dd:c25:c25:d00a:b1d9
2192c19:dd:d9:dd:c25:c25:d00a:b1da/1282c19:dd:d9:dd:c25:c25:d00a:b1da
2202c19:dd:d9:dd:c25:c25:d00a:b1db/1282c19:dd:d9:dd:c25:c25:d00a:b1db
2212c19:dd:d9:dd:c25:c25:d00a:b1dc/1282c19:dd:d9:dd:c25:c25:d00a:b1dc
2222c19:dd:d9:dd:c25:c25:d00a:b1dd/1282c19:dd:d9:dd:c25:c25:d00a:b1dd
2232c19:dd:d9:dd:c25:c25:d00a:b1de/1282c19:dd:d9:dd:c25:c25:d00a:b1de
2242c19:dd:d9:dd:c25:c25:d00a:b1df/1282c19:dd:d9:dd:c25:c25:d00a:b1df
2252c19:dd:d9:dd:c25:c25:d00a:b1e0/1282c19:dd:d9:dd:c25:c25:d00a:b1e0
2262c19:dd:d9:dd:c25:c25:d00a:b1e1/1282c19:dd:d9:dd:c25:c25:d00a:b1e1
2272c19:dd:d9:dd:c25:c25:d00a:b1e2/1282c19:dd:d9:dd:c25:c25:d00a:b1e2
2282c19:dd:d9:dd:c25:c25:d00a:b1e3/1282c19:dd:d9:dd:c25:c25:d00a:b1e3
2292c19:dd:d9:dd:c25:c25:d00a:b1e4/1282c19:dd:d9:dd:c25:c25:d00a:b1e4
2302c19:dd:d9:dd:c25:c25:d00a:b1e5/1282c19:dd:d9:dd:c25:c25:d00a:b1e5
2312c19:dd:d9:dd:c25:c25:d00a:b1e6/1282c19:dd:d9:dd:c25:c25:d00a:b1e6
2322c19:dd:d9:dd:c25:c25:d00a:b1e7/1282c19:dd:d9:dd:c25:c25:d00a:b1e7
2332c19:dd:d9:dd:c25:c25:d00a:b1e8/1282c19:dd:d9:dd:c25:c25:d00a:b1e8
2342c19:dd:d9:dd:c25:c25:d00a:b1e9/1282c19:dd:d9:dd:c25:c25:d00a:b1e9
2352c19:dd:d9:dd:c25:c25:d00a:b1ea/1282c19:dd:d9:dd:c25:c25:d00a:b1ea
2362c19:dd:d9:dd:c25:c25:d00a:b1eb/1282c19:dd:d9:dd:c25:c25:d00a:b1eb
2372c19:dd:d9:dd:c25:c25:d00a:b1ec/1282c19:dd:d9:dd:c25:c25:d00a:b1ec
2382c19:dd:d9:dd:c25:c25:d00a:b1ed/1282c19:dd:d9:dd:c25:c25:d00a:b1ed
2392c19:dd:d9:dd:c25:c25:d00a:b1ee/1282c19:dd:d9:dd:c25:c25:d00a:b1ee
2402c19:dd:d9:dd:c25:c25:d00a:b1ef/1282c19:dd:d9:dd:c25:c25:d00a:b1ef
2412c19:dd:d9:dd:c25:c25:d00a:b1f0/1282c19:dd:d9:dd:c25:c25:d00a:b1f0
2422c19:dd:d9:dd:c25:c25:d00a:b1f1/1282c19:dd:d9:dd:c25:c25:d00a:b1f1
2432c19:dd:d9:dd:c25:c25:d00a:b1f2/1282c19:dd:d9:dd:c25:c25:d00a:b1f2
2442c19:dd:d9:dd:c25:c25:d00a:b1f3/1282c19:dd:d9:dd:c25:c25:d00a:b1f3
2452c19:dd:d9:dd:c25:c25:d00a:b1f4/1282c19:dd:d9:dd:c25:c25:d00a:b1f4
2462c19:dd:d9:dd:c25:c25:d00a:b1f5/1282c19:dd:d9:dd:c25:c25:d00a:b1f5
2472c19:dd:d9:dd:c25:c25:d00a:b1f6/1282c19:dd:d9:dd:c25:c25:d00a:b1f6
2482c19:dd:d9:dd:c25:c25:d00a:b1f7/1282c19:dd:d9:dd:c25:c25:d00a:b1f7
2492c19:dd:d9:dd:c25:c25:d00a:b1f8/1282c19:dd:d9:dd:c25:c25:d00a:b1f8
2502c19:dd:d9:dd:c25:c25:d00a:b1f9/1282c19:dd:d9:dd:c25:c25:d00a:b1f9
2512c19:dd:d9:dd:c25:c25:d00a:b1fa/1282c19:dd:d9:dd:c25:c25:d00a:b1fa
2522c19:dd:d9:dd:c25:c25:d00a:b1fb/1282c19:dd:d9:dd:c25:c25:d00a:b1fb
2532c19:dd:d9:dd:c25:c25:d00a:b1fc/1282c19:dd:d9:dd:c25:c25:d00a:b1fc
2542c19:dd:d9:dd:c25:c25:d00a:b1fd/1282c19:dd:d9:dd:c25:c25:d00a:b1fd
2552c19:dd:d9:dd:c25:c25:d00a:b1fe/1282c19:dd:d9:dd:c25:c25:d00a:b1fe
2562c19:dd:d9:dd:c25:c25:d00a:b1ff/1282c19:dd:d9:dd:c25:c25:d00a:b1ff

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.