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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Prefix/120
Addresses256
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:94de:f100/120
First address
2c19:dd:d9:dd:c25:c25:94de:f100
Last address
2c19:dd:d9:dd:c25:c25:94de:f1ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:f100
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
1.f.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:94de:f100/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:f100/1282c19:dd:d9:dd:c25:c25:94de:f100
22c19:dd:d9:dd:c25:c25:94de:f101/1282c19:dd:d9:dd:c25:c25:94de:f101
32c19:dd:d9:dd:c25:c25:94de:f102/1282c19:dd:d9:dd:c25:c25:94de:f102
42c19:dd:d9:dd:c25:c25:94de:f103/1282c19:dd:d9:dd:c25:c25:94de:f103
52c19:dd:d9:dd:c25:c25:94de:f104/1282c19:dd:d9:dd:c25:c25:94de:f104
62c19:dd:d9:dd:c25:c25:94de:f105/1282c19:dd:d9:dd:c25:c25:94de:f105
72c19:dd:d9:dd:c25:c25:94de:f106/1282c19:dd:d9:dd:c25:c25:94de:f106
82c19:dd:d9:dd:c25:c25:94de:f107/1282c19:dd:d9:dd:c25:c25:94de:f107
92c19:dd:d9:dd:c25:c25:94de:f108/1282c19:dd:d9:dd:c25:c25:94de:f108
102c19:dd:d9:dd:c25:c25:94de:f109/1282c19:dd:d9:dd:c25:c25:94de:f109
112c19:dd:d9:dd:c25:c25:94de:f10a/1282c19:dd:d9:dd:c25:c25:94de:f10a
122c19:dd:d9:dd:c25:c25:94de:f10b/1282c19:dd:d9:dd:c25:c25:94de:f10b
132c19:dd:d9:dd:c25:c25:94de:f10c/1282c19:dd:d9:dd:c25:c25:94de:f10c
142c19:dd:d9:dd:c25:c25:94de:f10d/1282c19:dd:d9:dd:c25:c25:94de:f10d
152c19:dd:d9:dd:c25:c25:94de:f10e/1282c19:dd:d9:dd:c25:c25:94de:f10e
162c19:dd:d9:dd:c25:c25:94de:f10f/1282c19:dd:d9:dd:c25:c25:94de:f10f
172c19:dd:d9:dd:c25:c25:94de:f110/1282c19:dd:d9:dd:c25:c25:94de:f110
182c19:dd:d9:dd:c25:c25:94de:f111/1282c19:dd:d9:dd:c25:c25:94de:f111
192c19:dd:d9:dd:c25:c25:94de:f112/1282c19:dd:d9:dd:c25:c25:94de:f112
202c19:dd:d9:dd:c25:c25:94de:f113/1282c19:dd:d9:dd:c25:c25:94de:f113
212c19:dd:d9:dd:c25:c25:94de:f114/1282c19:dd:d9:dd:c25:c25:94de:f114
222c19:dd:d9:dd:c25:c25:94de:f115/1282c19:dd:d9:dd:c25:c25:94de:f115
232c19:dd:d9:dd:c25:c25:94de:f116/1282c19:dd:d9:dd:c25:c25:94de:f116
242c19:dd:d9:dd:c25:c25:94de:f117/1282c19:dd:d9:dd:c25:c25:94de:f117
252c19:dd:d9:dd:c25:c25:94de:f118/1282c19:dd:d9:dd:c25:c25:94de:f118
262c19:dd:d9:dd:c25:c25:94de:f119/1282c19:dd:d9:dd:c25:c25:94de:f119
272c19:dd:d9:dd:c25:c25:94de:f11a/1282c19:dd:d9:dd:c25:c25:94de:f11a
282c19:dd:d9:dd:c25:c25:94de:f11b/1282c19:dd:d9:dd:c25:c25:94de:f11b
292c19:dd:d9:dd:c25:c25:94de:f11c/1282c19:dd:d9:dd:c25:c25:94de:f11c
302c19:dd:d9:dd:c25:c25:94de:f11d/1282c19:dd:d9:dd:c25:c25:94de:f11d
312c19:dd:d9:dd:c25:c25:94de:f11e/1282c19:dd:d9:dd:c25:c25:94de:f11e
322c19:dd:d9:dd:c25:c25:94de:f11f/1282c19:dd:d9:dd:c25:c25:94de:f11f
332c19:dd:d9:dd:c25:c25:94de:f120/1282c19:dd:d9:dd:c25:c25:94de:f120
342c19:dd:d9:dd:c25:c25:94de:f121/1282c19:dd:d9:dd:c25:c25:94de:f121
352c19:dd:d9:dd:c25:c25:94de:f122/1282c19:dd:d9:dd:c25:c25:94de:f122
362c19:dd:d9:dd:c25:c25:94de:f123/1282c19:dd:d9:dd:c25:c25:94de:f123
372c19:dd:d9:dd:c25:c25:94de:f124/1282c19:dd:d9:dd:c25:c25:94de:f124
382c19:dd:d9:dd:c25:c25:94de:f125/1282c19:dd:d9:dd:c25:c25:94de:f125
392c19:dd:d9:dd:c25:c25:94de:f126/1282c19:dd:d9:dd:c25:c25:94de:f126
402c19:dd:d9:dd:c25:c25:94de:f127/1282c19:dd:d9:dd:c25:c25:94de:f127
412c19:dd:d9:dd:c25:c25:94de:f128/1282c19:dd:d9:dd:c25:c25:94de:f128
422c19:dd:d9:dd:c25:c25:94de:f129/1282c19:dd:d9:dd:c25:c25:94de:f129
432c19:dd:d9:dd:c25:c25:94de:f12a/1282c19:dd:d9:dd:c25:c25:94de:f12a
442c19:dd:d9:dd:c25:c25:94de:f12b/1282c19:dd:d9:dd:c25:c25:94de:f12b
452c19:dd:d9:dd:c25:c25:94de:f12c/1282c19:dd:d9:dd:c25:c25:94de:f12c
462c19:dd:d9:dd:c25:c25:94de:f12d/1282c19:dd:d9:dd:c25:c25:94de:f12d
472c19:dd:d9:dd:c25:c25:94de:f12e/1282c19:dd:d9:dd:c25:c25:94de:f12e
482c19:dd:d9:dd:c25:c25:94de:f12f/1282c19:dd:d9:dd:c25:c25:94de:f12f
492c19:dd:d9:dd:c25:c25:94de:f130/1282c19:dd:d9:dd:c25:c25:94de:f130
502c19:dd:d9:dd:c25:c25:94de:f131/1282c19:dd:d9:dd:c25:c25:94de:f131
512c19:dd:d9:dd:c25:c25:94de:f132/1282c19:dd:d9:dd:c25:c25:94de:f132
522c19:dd:d9:dd:c25:c25:94de:f133/1282c19:dd:d9:dd:c25:c25:94de:f133
532c19:dd:d9:dd:c25:c25:94de:f134/1282c19:dd:d9:dd:c25:c25:94de:f134
542c19:dd:d9:dd:c25:c25:94de:f135/1282c19:dd:d9:dd:c25:c25:94de:f135
552c19:dd:d9:dd:c25:c25:94de:f136/1282c19:dd:d9:dd:c25:c25:94de:f136
562c19:dd:d9:dd:c25:c25:94de:f137/1282c19:dd:d9:dd:c25:c25:94de:f137
572c19:dd:d9:dd:c25:c25:94de:f138/1282c19:dd:d9:dd:c25:c25:94de:f138
582c19:dd:d9:dd:c25:c25:94de:f139/1282c19:dd:d9:dd:c25:c25:94de:f139
592c19:dd:d9:dd:c25:c25:94de:f13a/1282c19:dd:d9:dd:c25:c25:94de:f13a
602c19:dd:d9:dd:c25:c25:94de:f13b/1282c19:dd:d9:dd:c25:c25:94de:f13b
612c19:dd:d9:dd:c25:c25:94de:f13c/1282c19:dd:d9:dd:c25:c25:94de:f13c
622c19:dd:d9:dd:c25:c25:94de:f13d/1282c19:dd:d9:dd:c25:c25:94de:f13d
632c19:dd:d9:dd:c25:c25:94de:f13e/1282c19:dd:d9:dd:c25:c25:94de:f13e
642c19:dd:d9:dd:c25:c25:94de:f13f/1282c19:dd:d9:dd:c25:c25:94de:f13f
652c19:dd:d9:dd:c25:c25:94de:f140/1282c19:dd:d9:dd:c25:c25:94de:f140
662c19:dd:d9:dd:c25:c25:94de:f141/1282c19:dd:d9:dd:c25:c25:94de:f141
672c19:dd:d9:dd:c25:c25:94de:f142/1282c19:dd:d9:dd:c25:c25:94de:f142
682c19:dd:d9:dd:c25:c25:94de:f143/1282c19:dd:d9:dd:c25:c25:94de:f143
692c19:dd:d9:dd:c25:c25:94de:f144/1282c19:dd:d9:dd:c25:c25:94de:f144
702c19:dd:d9:dd:c25:c25:94de:f145/1282c19:dd:d9:dd:c25:c25:94de:f145
712c19:dd:d9:dd:c25:c25:94de:f146/1282c19:dd:d9:dd:c25:c25:94de:f146
722c19:dd:d9:dd:c25:c25:94de:f147/1282c19:dd:d9:dd:c25:c25:94de:f147
732c19:dd:d9:dd:c25:c25:94de:f148/1282c19:dd:d9:dd:c25:c25:94de:f148
742c19:dd:d9:dd:c25:c25:94de:f149/1282c19:dd:d9:dd:c25:c25:94de:f149
752c19:dd:d9:dd:c25:c25:94de:f14a/1282c19:dd:d9:dd:c25:c25:94de:f14a
762c19:dd:d9:dd:c25:c25:94de:f14b/1282c19:dd:d9:dd:c25:c25:94de:f14b
772c19:dd:d9:dd:c25:c25:94de:f14c/1282c19:dd:d9:dd:c25:c25:94de:f14c
782c19:dd:d9:dd:c25:c25:94de:f14d/1282c19:dd:d9:dd:c25:c25:94de:f14d
792c19:dd:d9:dd:c25:c25:94de:f14e/1282c19:dd:d9:dd:c25:c25:94de:f14e
802c19:dd:d9:dd:c25:c25:94de:f14f/1282c19:dd:d9:dd:c25:c25:94de:f14f
812c19:dd:d9:dd:c25:c25:94de:f150/1282c19:dd:d9:dd:c25:c25:94de:f150
822c19:dd:d9:dd:c25:c25:94de:f151/1282c19:dd:d9:dd:c25:c25:94de:f151
832c19:dd:d9:dd:c25:c25:94de:f152/1282c19:dd:d9:dd:c25:c25:94de:f152
842c19:dd:d9:dd:c25:c25:94de:f153/1282c19:dd:d9:dd:c25:c25:94de:f153
852c19:dd:d9:dd:c25:c25:94de:f154/1282c19:dd:d9:dd:c25:c25:94de:f154
862c19:dd:d9:dd:c25:c25:94de:f155/1282c19:dd:d9:dd:c25:c25:94de:f155
872c19:dd:d9:dd:c25:c25:94de:f156/1282c19:dd:d9:dd:c25:c25:94de:f156
882c19:dd:d9:dd:c25:c25:94de:f157/1282c19:dd:d9:dd:c25:c25:94de:f157
892c19:dd:d9:dd:c25:c25:94de:f158/1282c19:dd:d9:dd:c25:c25:94de:f158
902c19:dd:d9:dd:c25:c25:94de:f159/1282c19:dd:d9:dd:c25:c25:94de:f159
912c19:dd:d9:dd:c25:c25:94de:f15a/1282c19:dd:d9:dd:c25:c25:94de:f15a
922c19:dd:d9:dd:c25:c25:94de:f15b/1282c19:dd:d9:dd:c25:c25:94de:f15b
932c19:dd:d9:dd:c25:c25:94de:f15c/1282c19:dd:d9:dd:c25:c25:94de:f15c
942c19:dd:d9:dd:c25:c25:94de:f15d/1282c19:dd:d9:dd:c25:c25:94de:f15d
952c19:dd:d9:dd:c25:c25:94de:f15e/1282c19:dd:d9:dd:c25:c25:94de:f15e
962c19:dd:d9:dd:c25:c25:94de:f15f/1282c19:dd:d9:dd:c25:c25:94de:f15f
972c19:dd:d9:dd:c25:c25:94de:f160/1282c19:dd:d9:dd:c25:c25:94de:f160
982c19:dd:d9:dd:c25:c25:94de:f161/1282c19:dd:d9:dd:c25:c25:94de:f161
992c19:dd:d9:dd:c25:c25:94de:f162/1282c19:dd:d9:dd:c25:c25:94de:f162
1002c19:dd:d9:dd:c25:c25:94de:f163/1282c19:dd:d9:dd:c25:c25:94de:f163
1012c19:dd:d9:dd:c25:c25:94de:f164/1282c19:dd:d9:dd:c25:c25:94de:f164
1022c19:dd:d9:dd:c25:c25:94de:f165/1282c19:dd:d9:dd:c25:c25:94de:f165
1032c19:dd:d9:dd:c25:c25:94de:f166/1282c19:dd:d9:dd:c25:c25:94de:f166
1042c19:dd:d9:dd:c25:c25:94de:f167/1282c19:dd:d9:dd:c25:c25:94de:f167
1052c19:dd:d9:dd:c25:c25:94de:f168/1282c19:dd:d9:dd:c25:c25:94de:f168
1062c19:dd:d9:dd:c25:c25:94de:f169/1282c19:dd:d9:dd:c25:c25:94de:f169
1072c19:dd:d9:dd:c25:c25:94de:f16a/1282c19:dd:d9:dd:c25:c25:94de:f16a
1082c19:dd:d9:dd:c25:c25:94de:f16b/1282c19:dd:d9:dd:c25:c25:94de:f16b
1092c19:dd:d9:dd:c25:c25:94de:f16c/1282c19:dd:d9:dd:c25:c25:94de:f16c
1102c19:dd:d9:dd:c25:c25:94de:f16d/1282c19:dd:d9:dd:c25:c25:94de:f16d
1112c19:dd:d9:dd:c25:c25:94de:f16e/1282c19:dd:d9:dd:c25:c25:94de:f16e
1122c19:dd:d9:dd:c25:c25:94de:f16f/1282c19:dd:d9:dd:c25:c25:94de:f16f
1132c19:dd:d9:dd:c25:c25:94de:f170/1282c19:dd:d9:dd:c25:c25:94de:f170
1142c19:dd:d9:dd:c25:c25:94de:f171/1282c19:dd:d9:dd:c25:c25:94de:f171
1152c19:dd:d9:dd:c25:c25:94de:f172/1282c19:dd:d9:dd:c25:c25:94de:f172
1162c19:dd:d9:dd:c25:c25:94de:f173/1282c19:dd:d9:dd:c25:c25:94de:f173
1172c19:dd:d9:dd:c25:c25:94de:f174/1282c19:dd:d9:dd:c25:c25:94de:f174
1182c19:dd:d9:dd:c25:c25:94de:f175/1282c19:dd:d9:dd:c25:c25:94de:f175
1192c19:dd:d9:dd:c25:c25:94de:f176/1282c19:dd:d9:dd:c25:c25:94de:f176
1202c19:dd:d9:dd:c25:c25:94de:f177/1282c19:dd:d9:dd:c25:c25:94de:f177
1212c19:dd:d9:dd:c25:c25:94de:f178/1282c19:dd:d9:dd:c25:c25:94de:f178
1222c19:dd:d9:dd:c25:c25:94de:f179/1282c19:dd:d9:dd:c25:c25:94de:f179
1232c19:dd:d9:dd:c25:c25:94de:f17a/1282c19:dd:d9:dd:c25:c25:94de:f17a
1242c19:dd:d9:dd:c25:c25:94de:f17b/1282c19:dd:d9:dd:c25:c25:94de:f17b
1252c19:dd:d9:dd:c25:c25:94de:f17c/1282c19:dd:d9:dd:c25:c25:94de:f17c
1262c19:dd:d9:dd:c25:c25:94de:f17d/1282c19:dd:d9:dd:c25:c25:94de:f17d
1272c19:dd:d9:dd:c25:c25:94de:f17e/1282c19:dd:d9:dd:c25:c25:94de:f17e
1282c19:dd:d9:dd:c25:c25:94de:f17f/1282c19:dd:d9:dd:c25:c25:94de:f17f
1292c19:dd:d9:dd:c25:c25:94de:f180/1282c19:dd:d9:dd:c25:c25:94de:f180
1302c19:dd:d9:dd:c25:c25:94de:f181/1282c19:dd:d9:dd:c25:c25:94de:f181
1312c19:dd:d9:dd:c25:c25:94de:f182/1282c19:dd:d9:dd:c25:c25:94de:f182
1322c19:dd:d9:dd:c25:c25:94de:f183/1282c19:dd:d9:dd:c25:c25:94de:f183
1332c19:dd:d9:dd:c25:c25:94de:f184/1282c19:dd:d9:dd:c25:c25:94de:f184
1342c19:dd:d9:dd:c25:c25:94de:f185/1282c19:dd:d9:dd:c25:c25:94de:f185
1352c19:dd:d9:dd:c25:c25:94de:f186/1282c19:dd:d9:dd:c25:c25:94de:f186
1362c19:dd:d9:dd:c25:c25:94de:f187/1282c19:dd:d9:dd:c25:c25:94de:f187
1372c19:dd:d9:dd:c25:c25:94de:f188/1282c19:dd:d9:dd:c25:c25:94de:f188
1382c19:dd:d9:dd:c25:c25:94de:f189/1282c19:dd:d9:dd:c25:c25:94de:f189
1392c19:dd:d9:dd:c25:c25:94de:f18a/1282c19:dd:d9:dd:c25:c25:94de:f18a
1402c19:dd:d9:dd:c25:c25:94de:f18b/1282c19:dd:d9:dd:c25:c25:94de:f18b
1412c19:dd:d9:dd:c25:c25:94de:f18c/1282c19:dd:d9:dd:c25:c25:94de:f18c
1422c19:dd:d9:dd:c25:c25:94de:f18d/1282c19:dd:d9:dd:c25:c25:94de:f18d
1432c19:dd:d9:dd:c25:c25:94de:f18e/1282c19:dd:d9:dd:c25:c25:94de:f18e
1442c19:dd:d9:dd:c25:c25:94de:f18f/1282c19:dd:d9:dd:c25:c25:94de:f18f
1452c19:dd:d9:dd:c25:c25:94de:f190/1282c19:dd:d9:dd:c25:c25:94de:f190
1462c19:dd:d9:dd:c25:c25:94de:f191/1282c19:dd:d9:dd:c25:c25:94de:f191
1472c19:dd:d9:dd:c25:c25:94de:f192/1282c19:dd:d9:dd:c25:c25:94de:f192
1482c19:dd:d9:dd:c25:c25:94de:f193/1282c19:dd:d9:dd:c25:c25:94de:f193
1492c19:dd:d9:dd:c25:c25:94de:f194/1282c19:dd:d9:dd:c25:c25:94de:f194
1502c19:dd:d9:dd:c25:c25:94de:f195/1282c19:dd:d9:dd:c25:c25:94de:f195
1512c19:dd:d9:dd:c25:c25:94de:f196/1282c19:dd:d9:dd:c25:c25:94de:f196
1522c19:dd:d9:dd:c25:c25:94de:f197/1282c19:dd:d9:dd:c25:c25:94de:f197
1532c19:dd:d9:dd:c25:c25:94de:f198/1282c19:dd:d9:dd:c25:c25:94de:f198
1542c19:dd:d9:dd:c25:c25:94de:f199/1282c19:dd:d9:dd:c25:c25:94de:f199
1552c19:dd:d9:dd:c25:c25:94de:f19a/1282c19:dd:d9:dd:c25:c25:94de:f19a
1562c19:dd:d9:dd:c25:c25:94de:f19b/1282c19:dd:d9:dd:c25:c25:94de:f19b
1572c19:dd:d9:dd:c25:c25:94de:f19c/1282c19:dd:d9:dd:c25:c25:94de:f19c
1582c19:dd:d9:dd:c25:c25:94de:f19d/1282c19:dd:d9:dd:c25:c25:94de:f19d
1592c19:dd:d9:dd:c25:c25:94de:f19e/1282c19:dd:d9:dd:c25:c25:94de:f19e
1602c19:dd:d9:dd:c25:c25:94de:f19f/1282c19:dd:d9:dd:c25:c25:94de:f19f
1612c19:dd:d9:dd:c25:c25:94de:f1a0/1282c19:dd:d9:dd:c25:c25:94de:f1a0
1622c19:dd:d9:dd:c25:c25:94de:f1a1/1282c19:dd:d9:dd:c25:c25:94de:f1a1
1632c19:dd:d9:dd:c25:c25:94de:f1a2/1282c19:dd:d9:dd:c25:c25:94de:f1a2
1642c19:dd:d9:dd:c25:c25:94de:f1a3/1282c19:dd:d9:dd:c25:c25:94de:f1a3
1652c19:dd:d9:dd:c25:c25:94de:f1a4/1282c19:dd:d9:dd:c25:c25:94de:f1a4
1662c19:dd:d9:dd:c25:c25:94de:f1a5/1282c19:dd:d9:dd:c25:c25:94de:f1a5
1672c19:dd:d9:dd:c25:c25:94de:f1a6/1282c19:dd:d9:dd:c25:c25:94de:f1a6
1682c19:dd:d9:dd:c25:c25:94de:f1a7/1282c19:dd:d9:dd:c25:c25:94de:f1a7
1692c19:dd:d9:dd:c25:c25:94de:f1a8/1282c19:dd:d9:dd:c25:c25:94de:f1a8
1702c19:dd:d9:dd:c25:c25:94de:f1a9/1282c19:dd:d9:dd:c25:c25:94de:f1a9
1712c19:dd:d9:dd:c25:c25:94de:f1aa/1282c19:dd:d9:dd:c25:c25:94de:f1aa
1722c19:dd:d9:dd:c25:c25:94de:f1ab/1282c19:dd:d9:dd:c25:c25:94de:f1ab
1732c19:dd:d9:dd:c25:c25:94de:f1ac/1282c19:dd:d9:dd:c25:c25:94de:f1ac
1742c19:dd:d9:dd:c25:c25:94de:f1ad/1282c19:dd:d9:dd:c25:c25:94de:f1ad
1752c19:dd:d9:dd:c25:c25:94de:f1ae/1282c19:dd:d9:dd:c25:c25:94de:f1ae
1762c19:dd:d9:dd:c25:c25:94de:f1af/1282c19:dd:d9:dd:c25:c25:94de:f1af
1772c19:dd:d9:dd:c25:c25:94de:f1b0/1282c19:dd:d9:dd:c25:c25:94de:f1b0
1782c19:dd:d9:dd:c25:c25:94de:f1b1/1282c19:dd:d9:dd:c25:c25:94de:f1b1
1792c19:dd:d9:dd:c25:c25:94de:f1b2/1282c19:dd:d9:dd:c25:c25:94de:f1b2
1802c19:dd:d9:dd:c25:c25:94de:f1b3/1282c19:dd:d9:dd:c25:c25:94de:f1b3
1812c19:dd:d9:dd:c25:c25:94de:f1b4/1282c19:dd:d9:dd:c25:c25:94de:f1b4
1822c19:dd:d9:dd:c25:c25:94de:f1b5/1282c19:dd:d9:dd:c25:c25:94de:f1b5
1832c19:dd:d9:dd:c25:c25:94de:f1b6/1282c19:dd:d9:dd:c25:c25:94de:f1b6
1842c19:dd:d9:dd:c25:c25:94de:f1b7/1282c19:dd:d9:dd:c25:c25:94de:f1b7
1852c19:dd:d9:dd:c25:c25:94de:f1b8/1282c19:dd:d9:dd:c25:c25:94de:f1b8
1862c19:dd:d9:dd:c25:c25:94de:f1b9/1282c19:dd:d9:dd:c25:c25:94de:f1b9
1872c19:dd:d9:dd:c25:c25:94de:f1ba/1282c19:dd:d9:dd:c25:c25:94de:f1ba
1882c19:dd:d9:dd:c25:c25:94de:f1bb/1282c19:dd:d9:dd:c25:c25:94de:f1bb
1892c19:dd:d9:dd:c25:c25:94de:f1bc/1282c19:dd:d9:dd:c25:c25:94de:f1bc
1902c19:dd:d9:dd:c25:c25:94de:f1bd/1282c19:dd:d9:dd:c25:c25:94de:f1bd
1912c19:dd:d9:dd:c25:c25:94de:f1be/1282c19:dd:d9:dd:c25:c25:94de:f1be
1922c19:dd:d9:dd:c25:c25:94de:f1bf/1282c19:dd:d9:dd:c25:c25:94de:f1bf
1932c19:dd:d9:dd:c25:c25:94de:f1c0/1282c19:dd:d9:dd:c25:c25:94de:f1c0
1942c19:dd:d9:dd:c25:c25:94de:f1c1/1282c19:dd:d9:dd:c25:c25:94de:f1c1
1952c19:dd:d9:dd:c25:c25:94de:f1c2/1282c19:dd:d9:dd:c25:c25:94de:f1c2
1962c19:dd:d9:dd:c25:c25:94de:f1c3/1282c19:dd:d9:dd:c25:c25:94de:f1c3
1972c19:dd:d9:dd:c25:c25:94de:f1c4/1282c19:dd:d9:dd:c25:c25:94de:f1c4
1982c19:dd:d9:dd:c25:c25:94de:f1c5/1282c19:dd:d9:dd:c25:c25:94de:f1c5
1992c19:dd:d9:dd:c25:c25:94de:f1c6/1282c19:dd:d9:dd:c25:c25:94de:f1c6
2002c19:dd:d9:dd:c25:c25:94de:f1c7/1282c19:dd:d9:dd:c25:c25:94de:f1c7
2012c19:dd:d9:dd:c25:c25:94de:f1c8/1282c19:dd:d9:dd:c25:c25:94de:f1c8
2022c19:dd:d9:dd:c25:c25:94de:f1c9/1282c19:dd:d9:dd:c25:c25:94de:f1c9
2032c19:dd:d9:dd:c25:c25:94de:f1ca/1282c19:dd:d9:dd:c25:c25:94de:f1ca
2042c19:dd:d9:dd:c25:c25:94de:f1cb/1282c19:dd:d9:dd:c25:c25:94de:f1cb
2052c19:dd:d9:dd:c25:c25:94de:f1cc/1282c19:dd:d9:dd:c25:c25:94de:f1cc
2062c19:dd:d9:dd:c25:c25:94de:f1cd/1282c19:dd:d9:dd:c25:c25:94de:f1cd
2072c19:dd:d9:dd:c25:c25:94de:f1ce/1282c19:dd:d9:dd:c25:c25:94de:f1ce
2082c19:dd:d9:dd:c25:c25:94de:f1cf/1282c19:dd:d9:dd:c25:c25:94de:f1cf
2092c19:dd:d9:dd:c25:c25:94de:f1d0/1282c19:dd:d9:dd:c25:c25:94de:f1d0
2102c19:dd:d9:dd:c25:c25:94de:f1d1/1282c19:dd:d9:dd:c25:c25:94de:f1d1
2112c19:dd:d9:dd:c25:c25:94de:f1d2/1282c19:dd:d9:dd:c25:c25:94de:f1d2
2122c19:dd:d9:dd:c25:c25:94de:f1d3/1282c19:dd:d9:dd:c25:c25:94de:f1d3
2132c19:dd:d9:dd:c25:c25:94de:f1d4/1282c19:dd:d9:dd:c25:c25:94de:f1d4
2142c19:dd:d9:dd:c25:c25:94de:f1d5/1282c19:dd:d9:dd:c25:c25:94de:f1d5
2152c19:dd:d9:dd:c25:c25:94de:f1d6/1282c19:dd:d9:dd:c25:c25:94de:f1d6
2162c19:dd:d9:dd:c25:c25:94de:f1d7/1282c19:dd:d9:dd:c25:c25:94de:f1d7
2172c19:dd:d9:dd:c25:c25:94de:f1d8/1282c19:dd:d9:dd:c25:c25:94de:f1d8
2182c19:dd:d9:dd:c25:c25:94de:f1d9/1282c19:dd:d9:dd:c25:c25:94de:f1d9
2192c19:dd:d9:dd:c25:c25:94de:f1da/1282c19:dd:d9:dd:c25:c25:94de:f1da
2202c19:dd:d9:dd:c25:c25:94de:f1db/1282c19:dd:d9:dd:c25:c25:94de:f1db
2212c19:dd:d9:dd:c25:c25:94de:f1dc/1282c19:dd:d9:dd:c25:c25:94de:f1dc
2222c19:dd:d9:dd:c25:c25:94de:f1dd/1282c19:dd:d9:dd:c25:c25:94de:f1dd
2232c19:dd:d9:dd:c25:c25:94de:f1de/1282c19:dd:d9:dd:c25:c25:94de:f1de
2242c19:dd:d9:dd:c25:c25:94de:f1df/1282c19:dd:d9:dd:c25:c25:94de:f1df
2252c19:dd:d9:dd:c25:c25:94de:f1e0/1282c19:dd:d9:dd:c25:c25:94de:f1e0
2262c19:dd:d9:dd:c25:c25:94de:f1e1/1282c19:dd:d9:dd:c25:c25:94de:f1e1
2272c19:dd:d9:dd:c25:c25:94de:f1e2/1282c19:dd:d9:dd:c25:c25:94de:f1e2
2282c19:dd:d9:dd:c25:c25:94de:f1e3/1282c19:dd:d9:dd:c25:c25:94de:f1e3
2292c19:dd:d9:dd:c25:c25:94de:f1e4/1282c19:dd:d9:dd:c25:c25:94de:f1e4
2302c19:dd:d9:dd:c25:c25:94de:f1e5/1282c19:dd:d9:dd:c25:c25:94de:f1e5
2312c19:dd:d9:dd:c25:c25:94de:f1e6/1282c19:dd:d9:dd:c25:c25:94de:f1e6
2322c19:dd:d9:dd:c25:c25:94de:f1e7/1282c19:dd:d9:dd:c25:c25:94de:f1e7
2332c19:dd:d9:dd:c25:c25:94de:f1e8/1282c19:dd:d9:dd:c25:c25:94de:f1e8
2342c19:dd:d9:dd:c25:c25:94de:f1e9/1282c19:dd:d9:dd:c25:c25:94de:f1e9
2352c19:dd:d9:dd:c25:c25:94de:f1ea/1282c19:dd:d9:dd:c25:c25:94de:f1ea
2362c19:dd:d9:dd:c25:c25:94de:f1eb/1282c19:dd:d9:dd:c25:c25:94de:f1eb
2372c19:dd:d9:dd:c25:c25:94de:f1ec/1282c19:dd:d9:dd:c25:c25:94de:f1ec
2382c19:dd:d9:dd:c25:c25:94de:f1ed/1282c19:dd:d9:dd:c25:c25:94de:f1ed
2392c19:dd:d9:dd:c25:c25:94de:f1ee/1282c19:dd:d9:dd:c25:c25:94de:f1ee
2402c19:dd:d9:dd:c25:c25:94de:f1ef/1282c19:dd:d9:dd:c25:c25:94de:f1ef
2412c19:dd:d9:dd:c25:c25:94de:f1f0/1282c19:dd:d9:dd:c25:c25:94de:f1f0
2422c19:dd:d9:dd:c25:c25:94de:f1f1/1282c19:dd:d9:dd:c25:c25:94de:f1f1
2432c19:dd:d9:dd:c25:c25:94de:f1f2/1282c19:dd:d9:dd:c25:c25:94de:f1f2
2442c19:dd:d9:dd:c25:c25:94de:f1f3/1282c19:dd:d9:dd:c25:c25:94de:f1f3
2452c19:dd:d9:dd:c25:c25:94de:f1f4/1282c19:dd:d9:dd:c25:c25:94de:f1f4
2462c19:dd:d9:dd:c25:c25:94de:f1f5/1282c19:dd:d9:dd:c25:c25:94de:f1f5
2472c19:dd:d9:dd:c25:c25:94de:f1f6/1282c19:dd:d9:dd:c25:c25:94de:f1f6
2482c19:dd:d9:dd:c25:c25:94de:f1f7/1282c19:dd:d9:dd:c25:c25:94de:f1f7
2492c19:dd:d9:dd:c25:c25:94de:f1f8/1282c19:dd:d9:dd:c25:c25:94de:f1f8
2502c19:dd:d9:dd:c25:c25:94de:f1f9/1282c19:dd:d9:dd:c25:c25:94de:f1f9
2512c19:dd:d9:dd:c25:c25:94de:f1fa/1282c19:dd:d9:dd:c25:c25:94de:f1fa
2522c19:dd:d9:dd:c25:c25:94de:f1fb/1282c19:dd:d9:dd:c25:c25:94de:f1fb
2532c19:dd:d9:dd:c25:c25:94de:f1fc/1282c19:dd:d9:dd:c25:c25:94de:f1fc
2542c19:dd:d9:dd:c25:c25:94de:f1fd/1282c19:dd:d9:dd:c25:c25:94de:f1fd
2552c19:dd:d9:dd:c25:c25:94de:f1fe/1282c19:dd:d9:dd:c25:c25:94de:f1fe
2562c19:dd:d9:dd:c25:c25:94de:f1ff/1282c19:dd:d9:dd:c25:c25:94de:f1ff

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.