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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:c25b:d00a:7100/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:7100
Last address
2c19:dd:d9:dd:c25:c25b:d00a:71ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:7100
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
1.7.a.0.0.d.b.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:c25b:d00a:7100/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:7100/1282c19:dd:d9:dd:c25:c25b:d00a:7100
22c19:dd:d9:dd:c25:c25b:d00a:7101/1282c19:dd:d9:dd:c25:c25b:d00a:7101
32c19:dd:d9:dd:c25:c25b:d00a:7102/1282c19:dd:d9:dd:c25:c25b:d00a:7102
42c19:dd:d9:dd:c25:c25b:d00a:7103/1282c19:dd:d9:dd:c25:c25b:d00a:7103
52c19:dd:d9:dd:c25:c25b:d00a:7104/1282c19:dd:d9:dd:c25:c25b:d00a:7104
62c19:dd:d9:dd:c25:c25b:d00a:7105/1282c19:dd:d9:dd:c25:c25b:d00a:7105
72c19:dd:d9:dd:c25:c25b:d00a:7106/1282c19:dd:d9:dd:c25:c25b:d00a:7106
82c19:dd:d9:dd:c25:c25b:d00a:7107/1282c19:dd:d9:dd:c25:c25b:d00a:7107
92c19:dd:d9:dd:c25:c25b:d00a:7108/1282c19:dd:d9:dd:c25:c25b:d00a:7108
102c19:dd:d9:dd:c25:c25b:d00a:7109/1282c19:dd:d9:dd:c25:c25b:d00a:7109
112c19:dd:d9:dd:c25:c25b:d00a:710a/1282c19:dd:d9:dd:c25:c25b:d00a:710a
122c19:dd:d9:dd:c25:c25b:d00a:710b/1282c19:dd:d9:dd:c25:c25b:d00a:710b
132c19:dd:d9:dd:c25:c25b:d00a:710c/1282c19:dd:d9:dd:c25:c25b:d00a:710c
142c19:dd:d9:dd:c25:c25b:d00a:710d/1282c19:dd:d9:dd:c25:c25b:d00a:710d
152c19:dd:d9:dd:c25:c25b:d00a:710e/1282c19:dd:d9:dd:c25:c25b:d00a:710e
162c19:dd:d9:dd:c25:c25b:d00a:710f/1282c19:dd:d9:dd:c25:c25b:d00a:710f
172c19:dd:d9:dd:c25:c25b:d00a:7110/1282c19:dd:d9:dd:c25:c25b:d00a:7110
182c19:dd:d9:dd:c25:c25b:d00a:7111/1282c19:dd:d9:dd:c25:c25b:d00a:7111
192c19:dd:d9:dd:c25:c25b:d00a:7112/1282c19:dd:d9:dd:c25:c25b:d00a:7112
202c19:dd:d9:dd:c25:c25b:d00a:7113/1282c19:dd:d9:dd:c25:c25b:d00a:7113
212c19:dd:d9:dd:c25:c25b:d00a:7114/1282c19:dd:d9:dd:c25:c25b:d00a:7114
222c19:dd:d9:dd:c25:c25b:d00a:7115/1282c19:dd:d9:dd:c25:c25b:d00a:7115
232c19:dd:d9:dd:c25:c25b:d00a:7116/1282c19:dd:d9:dd:c25:c25b:d00a:7116
242c19:dd:d9:dd:c25:c25b:d00a:7117/1282c19:dd:d9:dd:c25:c25b:d00a:7117
252c19:dd:d9:dd:c25:c25b:d00a:7118/1282c19:dd:d9:dd:c25:c25b:d00a:7118
262c19:dd:d9:dd:c25:c25b:d00a:7119/1282c19:dd:d9:dd:c25:c25b:d00a:7119
272c19:dd:d9:dd:c25:c25b:d00a:711a/1282c19:dd:d9:dd:c25:c25b:d00a:711a
282c19:dd:d9:dd:c25:c25b:d00a:711b/1282c19:dd:d9:dd:c25:c25b:d00a:711b
292c19:dd:d9:dd:c25:c25b:d00a:711c/1282c19:dd:d9:dd:c25:c25b:d00a:711c
302c19:dd:d9:dd:c25:c25b:d00a:711d/1282c19:dd:d9:dd:c25:c25b:d00a:711d
312c19:dd:d9:dd:c25:c25b:d00a:711e/1282c19:dd:d9:dd:c25:c25b:d00a:711e
322c19:dd:d9:dd:c25:c25b:d00a:711f/1282c19:dd:d9:dd:c25:c25b:d00a:711f
332c19:dd:d9:dd:c25:c25b:d00a:7120/1282c19:dd:d9:dd:c25:c25b:d00a:7120
342c19:dd:d9:dd:c25:c25b:d00a:7121/1282c19:dd:d9:dd:c25:c25b:d00a:7121
352c19:dd:d9:dd:c25:c25b:d00a:7122/1282c19:dd:d9:dd:c25:c25b:d00a:7122
362c19:dd:d9:dd:c25:c25b:d00a:7123/1282c19:dd:d9:dd:c25:c25b:d00a:7123
372c19:dd:d9:dd:c25:c25b:d00a:7124/1282c19:dd:d9:dd:c25:c25b:d00a:7124
382c19:dd:d9:dd:c25:c25b:d00a:7125/1282c19:dd:d9:dd:c25:c25b:d00a:7125
392c19:dd:d9:dd:c25:c25b:d00a:7126/1282c19:dd:d9:dd:c25:c25b:d00a:7126
402c19:dd:d9:dd:c25:c25b:d00a:7127/1282c19:dd:d9:dd:c25:c25b:d00a:7127
412c19:dd:d9:dd:c25:c25b:d00a:7128/1282c19:dd:d9:dd:c25:c25b:d00a:7128
422c19:dd:d9:dd:c25:c25b:d00a:7129/1282c19:dd:d9:dd:c25:c25b:d00a:7129
432c19:dd:d9:dd:c25:c25b:d00a:712a/1282c19:dd:d9:dd:c25:c25b:d00a:712a
442c19:dd:d9:dd:c25:c25b:d00a:712b/1282c19:dd:d9:dd:c25:c25b:d00a:712b
452c19:dd:d9:dd:c25:c25b:d00a:712c/1282c19:dd:d9:dd:c25:c25b:d00a:712c
462c19:dd:d9:dd:c25:c25b:d00a:712d/1282c19:dd:d9:dd:c25:c25b:d00a:712d
472c19:dd:d9:dd:c25:c25b:d00a:712e/1282c19:dd:d9:dd:c25:c25b:d00a:712e
482c19:dd:d9:dd:c25:c25b:d00a:712f/1282c19:dd:d9:dd:c25:c25b:d00a:712f
492c19:dd:d9:dd:c25:c25b:d00a:7130/1282c19:dd:d9:dd:c25:c25b:d00a:7130
502c19:dd:d9:dd:c25:c25b:d00a:7131/1282c19:dd:d9:dd:c25:c25b:d00a:7131
512c19:dd:d9:dd:c25:c25b:d00a:7132/1282c19:dd:d9:dd:c25:c25b:d00a:7132
522c19:dd:d9:dd:c25:c25b:d00a:7133/1282c19:dd:d9:dd:c25:c25b:d00a:7133
532c19:dd:d9:dd:c25:c25b:d00a:7134/1282c19:dd:d9:dd:c25:c25b:d00a:7134
542c19:dd:d9:dd:c25:c25b:d00a:7135/1282c19:dd:d9:dd:c25:c25b:d00a:7135
552c19:dd:d9:dd:c25:c25b:d00a:7136/1282c19:dd:d9:dd:c25:c25b:d00a:7136
562c19:dd:d9:dd:c25:c25b:d00a:7137/1282c19:dd:d9:dd:c25:c25b:d00a:7137
572c19:dd:d9:dd:c25:c25b:d00a:7138/1282c19:dd:d9:dd:c25:c25b:d00a:7138
582c19:dd:d9:dd:c25:c25b:d00a:7139/1282c19:dd:d9:dd:c25:c25b:d00a:7139
592c19:dd:d9:dd:c25:c25b:d00a:713a/1282c19:dd:d9:dd:c25:c25b:d00a:713a
602c19:dd:d9:dd:c25:c25b:d00a:713b/1282c19:dd:d9:dd:c25:c25b:d00a:713b
612c19:dd:d9:dd:c25:c25b:d00a:713c/1282c19:dd:d9:dd:c25:c25b:d00a:713c
622c19:dd:d9:dd:c25:c25b:d00a:713d/1282c19:dd:d9:dd:c25:c25b:d00a:713d
632c19:dd:d9:dd:c25:c25b:d00a:713e/1282c19:dd:d9:dd:c25:c25b:d00a:713e
642c19:dd:d9:dd:c25:c25b:d00a:713f/1282c19:dd:d9:dd:c25:c25b:d00a:713f
652c19:dd:d9:dd:c25:c25b:d00a:7140/1282c19:dd:d9:dd:c25:c25b:d00a:7140
662c19:dd:d9:dd:c25:c25b:d00a:7141/1282c19:dd:d9:dd:c25:c25b:d00a:7141
672c19:dd:d9:dd:c25:c25b:d00a:7142/1282c19:dd:d9:dd:c25:c25b:d00a:7142
682c19:dd:d9:dd:c25:c25b:d00a:7143/1282c19:dd:d9:dd:c25:c25b:d00a:7143
692c19:dd:d9:dd:c25:c25b:d00a:7144/1282c19:dd:d9:dd:c25:c25b:d00a:7144
702c19:dd:d9:dd:c25:c25b:d00a:7145/1282c19:dd:d9:dd:c25:c25b:d00a:7145
712c19:dd:d9:dd:c25:c25b:d00a:7146/1282c19:dd:d9:dd:c25:c25b:d00a:7146
722c19:dd:d9:dd:c25:c25b:d00a:7147/1282c19:dd:d9:dd:c25:c25b:d00a:7147
732c19:dd:d9:dd:c25:c25b:d00a:7148/1282c19:dd:d9:dd:c25:c25b:d00a:7148
742c19:dd:d9:dd:c25:c25b:d00a:7149/1282c19:dd:d9:dd:c25:c25b:d00a:7149
752c19:dd:d9:dd:c25:c25b:d00a:714a/1282c19:dd:d9:dd:c25:c25b:d00a:714a
762c19:dd:d9:dd:c25:c25b:d00a:714b/1282c19:dd:d9:dd:c25:c25b:d00a:714b
772c19:dd:d9:dd:c25:c25b:d00a:714c/1282c19:dd:d9:dd:c25:c25b:d00a:714c
782c19:dd:d9:dd:c25:c25b:d00a:714d/1282c19:dd:d9:dd:c25:c25b:d00a:714d
792c19:dd:d9:dd:c25:c25b:d00a:714e/1282c19:dd:d9:dd:c25:c25b:d00a:714e
802c19:dd:d9:dd:c25:c25b:d00a:714f/1282c19:dd:d9:dd:c25:c25b:d00a:714f
812c19:dd:d9:dd:c25:c25b:d00a:7150/1282c19:dd:d9:dd:c25:c25b:d00a:7150
822c19:dd:d9:dd:c25:c25b:d00a:7151/1282c19:dd:d9:dd:c25:c25b:d00a:7151
832c19:dd:d9:dd:c25:c25b:d00a:7152/1282c19:dd:d9:dd:c25:c25b:d00a:7152
842c19:dd:d9:dd:c25:c25b:d00a:7153/1282c19:dd:d9:dd:c25:c25b:d00a:7153
852c19:dd:d9:dd:c25:c25b:d00a:7154/1282c19:dd:d9:dd:c25:c25b:d00a:7154
862c19:dd:d9:dd:c25:c25b:d00a:7155/1282c19:dd:d9:dd:c25:c25b:d00a:7155
872c19:dd:d9:dd:c25:c25b:d00a:7156/1282c19:dd:d9:dd:c25:c25b:d00a:7156
882c19:dd:d9:dd:c25:c25b:d00a:7157/1282c19:dd:d9:dd:c25:c25b:d00a:7157
892c19:dd:d9:dd:c25:c25b:d00a:7158/1282c19:dd:d9:dd:c25:c25b:d00a:7158
902c19:dd:d9:dd:c25:c25b:d00a:7159/1282c19:dd:d9:dd:c25:c25b:d00a:7159
912c19:dd:d9:dd:c25:c25b:d00a:715a/1282c19:dd:d9:dd:c25:c25b:d00a:715a
922c19:dd:d9:dd:c25:c25b:d00a:715b/1282c19:dd:d9:dd:c25:c25b:d00a:715b
932c19:dd:d9:dd:c25:c25b:d00a:715c/1282c19:dd:d9:dd:c25:c25b:d00a:715c
942c19:dd:d9:dd:c25:c25b:d00a:715d/1282c19:dd:d9:dd:c25:c25b:d00a:715d
952c19:dd:d9:dd:c25:c25b:d00a:715e/1282c19:dd:d9:dd:c25:c25b:d00a:715e
962c19:dd:d9:dd:c25:c25b:d00a:715f/1282c19:dd:d9:dd:c25:c25b:d00a:715f
972c19:dd:d9:dd:c25:c25b:d00a:7160/1282c19:dd:d9:dd:c25:c25b:d00a:7160
982c19:dd:d9:dd:c25:c25b:d00a:7161/1282c19:dd:d9:dd:c25:c25b:d00a:7161
992c19:dd:d9:dd:c25:c25b:d00a:7162/1282c19:dd:d9:dd:c25:c25b:d00a:7162
1002c19:dd:d9:dd:c25:c25b:d00a:7163/1282c19:dd:d9:dd:c25:c25b:d00a:7163
1012c19:dd:d9:dd:c25:c25b:d00a:7164/1282c19:dd:d9:dd:c25:c25b:d00a:7164
1022c19:dd:d9:dd:c25:c25b:d00a:7165/1282c19:dd:d9:dd:c25:c25b:d00a:7165
1032c19:dd:d9:dd:c25:c25b:d00a:7166/1282c19:dd:d9:dd:c25:c25b:d00a:7166
1042c19:dd:d9:dd:c25:c25b:d00a:7167/1282c19:dd:d9:dd:c25:c25b:d00a:7167
1052c19:dd:d9:dd:c25:c25b:d00a:7168/1282c19:dd:d9:dd:c25:c25b:d00a:7168
1062c19:dd:d9:dd:c25:c25b:d00a:7169/1282c19:dd:d9:dd:c25:c25b:d00a:7169
1072c19:dd:d9:dd:c25:c25b:d00a:716a/1282c19:dd:d9:dd:c25:c25b:d00a:716a
1082c19:dd:d9:dd:c25:c25b:d00a:716b/1282c19:dd:d9:dd:c25:c25b:d00a:716b
1092c19:dd:d9:dd:c25:c25b:d00a:716c/1282c19:dd:d9:dd:c25:c25b:d00a:716c
1102c19:dd:d9:dd:c25:c25b:d00a:716d/1282c19:dd:d9:dd:c25:c25b:d00a:716d
1112c19:dd:d9:dd:c25:c25b:d00a:716e/1282c19:dd:d9:dd:c25:c25b:d00a:716e
1122c19:dd:d9:dd:c25:c25b:d00a:716f/1282c19:dd:d9:dd:c25:c25b:d00a:716f
1132c19:dd:d9:dd:c25:c25b:d00a:7170/1282c19:dd:d9:dd:c25:c25b:d00a:7170
1142c19:dd:d9:dd:c25:c25b:d00a:7171/1282c19:dd:d9:dd:c25:c25b:d00a:7171
1152c19:dd:d9:dd:c25:c25b:d00a:7172/1282c19:dd:d9:dd:c25:c25b:d00a:7172
1162c19:dd:d9:dd:c25:c25b:d00a:7173/1282c19:dd:d9:dd:c25:c25b:d00a:7173
1172c19:dd:d9:dd:c25:c25b:d00a:7174/1282c19:dd:d9:dd:c25:c25b:d00a:7174
1182c19:dd:d9:dd:c25:c25b:d00a:7175/1282c19:dd:d9:dd:c25:c25b:d00a:7175
1192c19:dd:d9:dd:c25:c25b:d00a:7176/1282c19:dd:d9:dd:c25:c25b:d00a:7176
1202c19:dd:d9:dd:c25:c25b:d00a:7177/1282c19:dd:d9:dd:c25:c25b:d00a:7177
1212c19:dd:d9:dd:c25:c25b:d00a:7178/1282c19:dd:d9:dd:c25:c25b:d00a:7178
1222c19:dd:d9:dd:c25:c25b:d00a:7179/1282c19:dd:d9:dd:c25:c25b:d00a:7179
1232c19:dd:d9:dd:c25:c25b:d00a:717a/1282c19:dd:d9:dd:c25:c25b:d00a:717a
1242c19:dd:d9:dd:c25:c25b:d00a:717b/1282c19:dd:d9:dd:c25:c25b:d00a:717b
1252c19:dd:d9:dd:c25:c25b:d00a:717c/1282c19:dd:d9:dd:c25:c25b:d00a:717c
1262c19:dd:d9:dd:c25:c25b:d00a:717d/1282c19:dd:d9:dd:c25:c25b:d00a:717d
1272c19:dd:d9:dd:c25:c25b:d00a:717e/1282c19:dd:d9:dd:c25:c25b:d00a:717e
1282c19:dd:d9:dd:c25:c25b:d00a:717f/1282c19:dd:d9:dd:c25:c25b:d00a:717f
1292c19:dd:d9:dd:c25:c25b:d00a:7180/1282c19:dd:d9:dd:c25:c25b:d00a:7180
1302c19:dd:d9:dd:c25:c25b:d00a:7181/1282c19:dd:d9:dd:c25:c25b:d00a:7181
1312c19:dd:d9:dd:c25:c25b:d00a:7182/1282c19:dd:d9:dd:c25:c25b:d00a:7182
1322c19:dd:d9:dd:c25:c25b:d00a:7183/1282c19:dd:d9:dd:c25:c25b:d00a:7183
1332c19:dd:d9:dd:c25:c25b:d00a:7184/1282c19:dd:d9:dd:c25:c25b:d00a:7184
1342c19:dd:d9:dd:c25:c25b:d00a:7185/1282c19:dd:d9:dd:c25:c25b:d00a:7185
1352c19:dd:d9:dd:c25:c25b:d00a:7186/1282c19:dd:d9:dd:c25:c25b:d00a:7186
1362c19:dd:d9:dd:c25:c25b:d00a:7187/1282c19:dd:d9:dd:c25:c25b:d00a:7187
1372c19:dd:d9:dd:c25:c25b:d00a:7188/1282c19:dd:d9:dd:c25:c25b:d00a:7188
1382c19:dd:d9:dd:c25:c25b:d00a:7189/1282c19:dd:d9:dd:c25:c25b:d00a:7189
1392c19:dd:d9:dd:c25:c25b:d00a:718a/1282c19:dd:d9:dd:c25:c25b:d00a:718a
1402c19:dd:d9:dd:c25:c25b:d00a:718b/1282c19:dd:d9:dd:c25:c25b:d00a:718b
1412c19:dd:d9:dd:c25:c25b:d00a:718c/1282c19:dd:d9:dd:c25:c25b:d00a:718c
1422c19:dd:d9:dd:c25:c25b:d00a:718d/1282c19:dd:d9:dd:c25:c25b:d00a:718d
1432c19:dd:d9:dd:c25:c25b:d00a:718e/1282c19:dd:d9:dd:c25:c25b:d00a:718e
1442c19:dd:d9:dd:c25:c25b:d00a:718f/1282c19:dd:d9:dd:c25:c25b:d00a:718f
1452c19:dd:d9:dd:c25:c25b:d00a:7190/1282c19:dd:d9:dd:c25:c25b:d00a:7190
1462c19:dd:d9:dd:c25:c25b:d00a:7191/1282c19:dd:d9:dd:c25:c25b:d00a:7191
1472c19:dd:d9:dd:c25:c25b:d00a:7192/1282c19:dd:d9:dd:c25:c25b:d00a:7192
1482c19:dd:d9:dd:c25:c25b:d00a:7193/1282c19:dd:d9:dd:c25:c25b:d00a:7193
1492c19:dd:d9:dd:c25:c25b:d00a:7194/1282c19:dd:d9:dd:c25:c25b:d00a:7194
1502c19:dd:d9:dd:c25:c25b:d00a:7195/1282c19:dd:d9:dd:c25:c25b:d00a:7195
1512c19:dd:d9:dd:c25:c25b:d00a:7196/1282c19:dd:d9:dd:c25:c25b:d00a:7196
1522c19:dd:d9:dd:c25:c25b:d00a:7197/1282c19:dd:d9:dd:c25:c25b:d00a:7197
1532c19:dd:d9:dd:c25:c25b:d00a:7198/1282c19:dd:d9:dd:c25:c25b:d00a:7198
1542c19:dd:d9:dd:c25:c25b:d00a:7199/1282c19:dd:d9:dd:c25:c25b:d00a:7199
1552c19:dd:d9:dd:c25:c25b:d00a:719a/1282c19:dd:d9:dd:c25:c25b:d00a:719a
1562c19:dd:d9:dd:c25:c25b:d00a:719b/1282c19:dd:d9:dd:c25:c25b:d00a:719b
1572c19:dd:d9:dd:c25:c25b:d00a:719c/1282c19:dd:d9:dd:c25:c25b:d00a:719c
1582c19:dd:d9:dd:c25:c25b:d00a:719d/1282c19:dd:d9:dd:c25:c25b:d00a:719d
1592c19:dd:d9:dd:c25:c25b:d00a:719e/1282c19:dd:d9:dd:c25:c25b:d00a:719e
1602c19:dd:d9:dd:c25:c25b:d00a:719f/1282c19:dd:d9:dd:c25:c25b:d00a:719f
1612c19:dd:d9:dd:c25:c25b:d00a:71a0/1282c19:dd:d9:dd:c25:c25b:d00a:71a0
1622c19:dd:d9:dd:c25:c25b:d00a:71a1/1282c19:dd:d9:dd:c25:c25b:d00a:71a1
1632c19:dd:d9:dd:c25:c25b:d00a:71a2/1282c19:dd:d9:dd:c25:c25b:d00a:71a2
1642c19:dd:d9:dd:c25:c25b:d00a:71a3/1282c19:dd:d9:dd:c25:c25b:d00a:71a3
1652c19:dd:d9:dd:c25:c25b:d00a:71a4/1282c19:dd:d9:dd:c25:c25b:d00a:71a4
1662c19:dd:d9:dd:c25:c25b:d00a:71a5/1282c19:dd:d9:dd:c25:c25b:d00a:71a5
1672c19:dd:d9:dd:c25:c25b:d00a:71a6/1282c19:dd:d9:dd:c25:c25b:d00a:71a6
1682c19:dd:d9:dd:c25:c25b:d00a:71a7/1282c19:dd:d9:dd:c25:c25b:d00a:71a7
1692c19:dd:d9:dd:c25:c25b:d00a:71a8/1282c19:dd:d9:dd:c25:c25b:d00a:71a8
1702c19:dd:d9:dd:c25:c25b:d00a:71a9/1282c19:dd:d9:dd:c25:c25b:d00a:71a9
1712c19:dd:d9:dd:c25:c25b:d00a:71aa/1282c19:dd:d9:dd:c25:c25b:d00a:71aa
1722c19:dd:d9:dd:c25:c25b:d00a:71ab/1282c19:dd:d9:dd:c25:c25b:d00a:71ab
1732c19:dd:d9:dd:c25:c25b:d00a:71ac/1282c19:dd:d9:dd:c25:c25b:d00a:71ac
1742c19:dd:d9:dd:c25:c25b:d00a:71ad/1282c19:dd:d9:dd:c25:c25b:d00a:71ad
1752c19:dd:d9:dd:c25:c25b:d00a:71ae/1282c19:dd:d9:dd:c25:c25b:d00a:71ae
1762c19:dd:d9:dd:c25:c25b:d00a:71af/1282c19:dd:d9:dd:c25:c25b:d00a:71af
1772c19:dd:d9:dd:c25:c25b:d00a:71b0/1282c19:dd:d9:dd:c25:c25b:d00a:71b0
1782c19:dd:d9:dd:c25:c25b:d00a:71b1/1282c19:dd:d9:dd:c25:c25b:d00a:71b1
1792c19:dd:d9:dd:c25:c25b:d00a:71b2/1282c19:dd:d9:dd:c25:c25b:d00a:71b2
1802c19:dd:d9:dd:c25:c25b:d00a:71b3/1282c19:dd:d9:dd:c25:c25b:d00a:71b3
1812c19:dd:d9:dd:c25:c25b:d00a:71b4/1282c19:dd:d9:dd:c25:c25b:d00a:71b4
1822c19:dd:d9:dd:c25:c25b:d00a:71b5/1282c19:dd:d9:dd:c25:c25b:d00a:71b5
1832c19:dd:d9:dd:c25:c25b:d00a:71b6/1282c19:dd:d9:dd:c25:c25b:d00a:71b6
1842c19:dd:d9:dd:c25:c25b:d00a:71b7/1282c19:dd:d9:dd:c25:c25b:d00a:71b7
1852c19:dd:d9:dd:c25:c25b:d00a:71b8/1282c19:dd:d9:dd:c25:c25b:d00a:71b8
1862c19:dd:d9:dd:c25:c25b:d00a:71b9/1282c19:dd:d9:dd:c25:c25b:d00a:71b9
1872c19:dd:d9:dd:c25:c25b:d00a:71ba/1282c19:dd:d9:dd:c25:c25b:d00a:71ba
1882c19:dd:d9:dd:c25:c25b:d00a:71bb/1282c19:dd:d9:dd:c25:c25b:d00a:71bb
1892c19:dd:d9:dd:c25:c25b:d00a:71bc/1282c19:dd:d9:dd:c25:c25b:d00a:71bc
1902c19:dd:d9:dd:c25:c25b:d00a:71bd/1282c19:dd:d9:dd:c25:c25b:d00a:71bd
1912c19:dd:d9:dd:c25:c25b:d00a:71be/1282c19:dd:d9:dd:c25:c25b:d00a:71be
1922c19:dd:d9:dd:c25:c25b:d00a:71bf/1282c19:dd:d9:dd:c25:c25b:d00a:71bf
1932c19:dd:d9:dd:c25:c25b:d00a:71c0/1282c19:dd:d9:dd:c25:c25b:d00a:71c0
1942c19:dd:d9:dd:c25:c25b:d00a:71c1/1282c19:dd:d9:dd:c25:c25b:d00a:71c1
1952c19:dd:d9:dd:c25:c25b:d00a:71c2/1282c19:dd:d9:dd:c25:c25b:d00a:71c2
1962c19:dd:d9:dd:c25:c25b:d00a:71c3/1282c19:dd:d9:dd:c25:c25b:d00a:71c3
1972c19:dd:d9:dd:c25:c25b:d00a:71c4/1282c19:dd:d9:dd:c25:c25b:d00a:71c4
1982c19:dd:d9:dd:c25:c25b:d00a:71c5/1282c19:dd:d9:dd:c25:c25b:d00a:71c5
1992c19:dd:d9:dd:c25:c25b:d00a:71c6/1282c19:dd:d9:dd:c25:c25b:d00a:71c6
2002c19:dd:d9:dd:c25:c25b:d00a:71c7/1282c19:dd:d9:dd:c25:c25b:d00a:71c7
2012c19:dd:d9:dd:c25:c25b:d00a:71c8/1282c19:dd:d9:dd:c25:c25b:d00a:71c8
2022c19:dd:d9:dd:c25:c25b:d00a:71c9/1282c19:dd:d9:dd:c25:c25b:d00a:71c9
2032c19:dd:d9:dd:c25:c25b:d00a:71ca/1282c19:dd:d9:dd:c25:c25b:d00a:71ca
2042c19:dd:d9:dd:c25:c25b:d00a:71cb/1282c19:dd:d9:dd:c25:c25b:d00a:71cb
2052c19:dd:d9:dd:c25:c25b:d00a:71cc/1282c19:dd:d9:dd:c25:c25b:d00a:71cc
2062c19:dd:d9:dd:c25:c25b:d00a:71cd/1282c19:dd:d9:dd:c25:c25b:d00a:71cd
2072c19:dd:d9:dd:c25:c25b:d00a:71ce/1282c19:dd:d9:dd:c25:c25b:d00a:71ce
2082c19:dd:d9:dd:c25:c25b:d00a:71cf/1282c19:dd:d9:dd:c25:c25b:d00a:71cf
2092c19:dd:d9:dd:c25:c25b:d00a:71d0/1282c19:dd:d9:dd:c25:c25b:d00a:71d0
2102c19:dd:d9:dd:c25:c25b:d00a:71d1/1282c19:dd:d9:dd:c25:c25b:d00a:71d1
2112c19:dd:d9:dd:c25:c25b:d00a:71d2/1282c19:dd:d9:dd:c25:c25b:d00a:71d2
2122c19:dd:d9:dd:c25:c25b:d00a:71d3/1282c19:dd:d9:dd:c25:c25b:d00a:71d3
2132c19:dd:d9:dd:c25:c25b:d00a:71d4/1282c19:dd:d9:dd:c25:c25b:d00a:71d4
2142c19:dd:d9:dd:c25:c25b:d00a:71d5/1282c19:dd:d9:dd:c25:c25b:d00a:71d5
2152c19:dd:d9:dd:c25:c25b:d00a:71d6/1282c19:dd:d9:dd:c25:c25b:d00a:71d6
2162c19:dd:d9:dd:c25:c25b:d00a:71d7/1282c19:dd:d9:dd:c25:c25b:d00a:71d7
2172c19:dd:d9:dd:c25:c25b:d00a:71d8/1282c19:dd:d9:dd:c25:c25b:d00a:71d8
2182c19:dd:d9:dd:c25:c25b:d00a:71d9/1282c19:dd:d9:dd:c25:c25b:d00a:71d9
2192c19:dd:d9:dd:c25:c25b:d00a:71da/1282c19:dd:d9:dd:c25:c25b:d00a:71da
2202c19:dd:d9:dd:c25:c25b:d00a:71db/1282c19:dd:d9:dd:c25:c25b:d00a:71db
2212c19:dd:d9:dd:c25:c25b:d00a:71dc/1282c19:dd:d9:dd:c25:c25b:d00a:71dc
2222c19:dd:d9:dd:c25:c25b:d00a:71dd/1282c19:dd:d9:dd:c25:c25b:d00a:71dd
2232c19:dd:d9:dd:c25:c25b:d00a:71de/1282c19:dd:d9:dd:c25:c25b:d00a:71de
2242c19:dd:d9:dd:c25:c25b:d00a:71df/1282c19:dd:d9:dd:c25:c25b:d00a:71df
2252c19:dd:d9:dd:c25:c25b:d00a:71e0/1282c19:dd:d9:dd:c25:c25b:d00a:71e0
2262c19:dd:d9:dd:c25:c25b:d00a:71e1/1282c19:dd:d9:dd:c25:c25b:d00a:71e1
2272c19:dd:d9:dd:c25:c25b:d00a:71e2/1282c19:dd:d9:dd:c25:c25b:d00a:71e2
2282c19:dd:d9:dd:c25:c25b:d00a:71e3/1282c19:dd:d9:dd:c25:c25b:d00a:71e3
2292c19:dd:d9:dd:c25:c25b:d00a:71e4/1282c19:dd:d9:dd:c25:c25b:d00a:71e4
2302c19:dd:d9:dd:c25:c25b:d00a:71e5/1282c19:dd:d9:dd:c25:c25b:d00a:71e5
2312c19:dd:d9:dd:c25:c25b:d00a:71e6/1282c19:dd:d9:dd:c25:c25b:d00a:71e6
2322c19:dd:d9:dd:c25:c25b:d00a:71e7/1282c19:dd:d9:dd:c25:c25b:d00a:71e7
2332c19:dd:d9:dd:c25:c25b:d00a:71e8/1282c19:dd:d9:dd:c25:c25b:d00a:71e8
2342c19:dd:d9:dd:c25:c25b:d00a:71e9/1282c19:dd:d9:dd:c25:c25b:d00a:71e9
2352c19:dd:d9:dd:c25:c25b:d00a:71ea/1282c19:dd:d9:dd:c25:c25b:d00a:71ea
2362c19:dd:d9:dd:c25:c25b:d00a:71eb/1282c19:dd:d9:dd:c25:c25b:d00a:71eb
2372c19:dd:d9:dd:c25:c25b:d00a:71ec/1282c19:dd:d9:dd:c25:c25b:d00a:71ec
2382c19:dd:d9:dd:c25:c25b:d00a:71ed/1282c19:dd:d9:dd:c25:c25b:d00a:71ed
2392c19:dd:d9:dd:c25:c25b:d00a:71ee/1282c19:dd:d9:dd:c25:c25b:d00a:71ee
2402c19:dd:d9:dd:c25:c25b:d00a:71ef/1282c19:dd:d9:dd:c25:c25b:d00a:71ef
2412c19:dd:d9:dd:c25:c25b:d00a:71f0/1282c19:dd:d9:dd:c25:c25b:d00a:71f0
2422c19:dd:d9:dd:c25:c25b:d00a:71f1/1282c19:dd:d9:dd:c25:c25b:d00a:71f1
2432c19:dd:d9:dd:c25:c25b:d00a:71f2/1282c19:dd:d9:dd:c25:c25b:d00a:71f2
2442c19:dd:d9:dd:c25:c25b:d00a:71f3/1282c19:dd:d9:dd:c25:c25b:d00a:71f3
2452c19:dd:d9:dd:c25:c25b:d00a:71f4/1282c19:dd:d9:dd:c25:c25b:d00a:71f4
2462c19:dd:d9:dd:c25:c25b:d00a:71f5/1282c19:dd:d9:dd:c25:c25b:d00a:71f5
2472c19:dd:d9:dd:c25:c25b:d00a:71f6/1282c19:dd:d9:dd:c25:c25b:d00a:71f6
2482c19:dd:d9:dd:c25:c25b:d00a:71f7/1282c19:dd:d9:dd:c25:c25b:d00a:71f7
2492c19:dd:d9:dd:c25:c25b:d00a:71f8/1282c19:dd:d9:dd:c25:c25b:d00a:71f8
2502c19:dd:d9:dd:c25:c25b:d00a:71f9/1282c19:dd:d9:dd:c25:c25b:d00a:71f9
2512c19:dd:d9:dd:c25:c25b:d00a:71fa/1282c19:dd:d9:dd:c25:c25b:d00a:71fa
2522c19:dd:d9:dd:c25:c25b:d00a:71fb/1282c19:dd:d9:dd:c25:c25b:d00a:71fb
2532c19:dd:d9:dd:c25:c25b:d00a:71fc/1282c19:dd:d9:dd:c25:c25b:d00a:71fc
2542c19:dd:d9:dd:c25:c25b:d00a:71fd/1282c19:dd:d9:dd:c25:c25b:d00a:71fd
2552c19:dd:d9:dd:c25:c25b:d00a:71fe/1282c19:dd:d9:dd:c25:c25b:d00a:71fe
2562c19:dd:d9:dd:c25:c25b:d00a:71ff/1282c19:dd:d9:dd:c25:c25b:d00a:71ff

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.