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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:c25:c25:dd:dd:dd:1100/120
First address
2c19:dd:c25:c25:dd:dd:dd:1100
Last address
2c19:dd:c25:c25:dd:dd:dd:11ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:0c25:00dd:00dd:00dd:1100
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
1.1.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.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:c25:c25:dd:dd:dd:1100/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:c25:c25:dd:dd:dd:1100/1282c19:dd:c25:c25:dd:dd:dd:1100
22c19:dd:c25:c25:dd:dd:dd:1101/1282c19:dd:c25:c25:dd:dd:dd:1101
32c19:dd:c25:c25:dd:dd:dd:1102/1282c19:dd:c25:c25:dd:dd:dd:1102
42c19:dd:c25:c25:dd:dd:dd:1103/1282c19:dd:c25:c25:dd:dd:dd:1103
52c19:dd:c25:c25:dd:dd:dd:1104/1282c19:dd:c25:c25:dd:dd:dd:1104
62c19:dd:c25:c25:dd:dd:dd:1105/1282c19:dd:c25:c25:dd:dd:dd:1105
72c19:dd:c25:c25:dd:dd:dd:1106/1282c19:dd:c25:c25:dd:dd:dd:1106
82c19:dd:c25:c25:dd:dd:dd:1107/1282c19:dd:c25:c25:dd:dd:dd:1107
92c19:dd:c25:c25:dd:dd:dd:1108/1282c19:dd:c25:c25:dd:dd:dd:1108
102c19:dd:c25:c25:dd:dd:dd:1109/1282c19:dd:c25:c25:dd:dd:dd:1109
112c19:dd:c25:c25:dd:dd:dd:110a/1282c19:dd:c25:c25:dd:dd:dd:110a
122c19:dd:c25:c25:dd:dd:dd:110b/1282c19:dd:c25:c25:dd:dd:dd:110b
132c19:dd:c25:c25:dd:dd:dd:110c/1282c19:dd:c25:c25:dd:dd:dd:110c
142c19:dd:c25:c25:dd:dd:dd:110d/1282c19:dd:c25:c25:dd:dd:dd:110d
152c19:dd:c25:c25:dd:dd:dd:110e/1282c19:dd:c25:c25:dd:dd:dd:110e
162c19:dd:c25:c25:dd:dd:dd:110f/1282c19:dd:c25:c25:dd:dd:dd:110f
172c19:dd:c25:c25:dd:dd:dd:1110/1282c19:dd:c25:c25:dd:dd:dd:1110
182c19:dd:c25:c25:dd:dd:dd:1111/1282c19:dd:c25:c25:dd:dd:dd:1111
192c19:dd:c25:c25:dd:dd:dd:1112/1282c19:dd:c25:c25:dd:dd:dd:1112
202c19:dd:c25:c25:dd:dd:dd:1113/1282c19:dd:c25:c25:dd:dd:dd:1113
212c19:dd:c25:c25:dd:dd:dd:1114/1282c19:dd:c25:c25:dd:dd:dd:1114
222c19:dd:c25:c25:dd:dd:dd:1115/1282c19:dd:c25:c25:dd:dd:dd:1115
232c19:dd:c25:c25:dd:dd:dd:1116/1282c19:dd:c25:c25:dd:dd:dd:1116
242c19:dd:c25:c25:dd:dd:dd:1117/1282c19:dd:c25:c25:dd:dd:dd:1117
252c19:dd:c25:c25:dd:dd:dd:1118/1282c19:dd:c25:c25:dd:dd:dd:1118
262c19:dd:c25:c25:dd:dd:dd:1119/1282c19:dd:c25:c25:dd:dd:dd:1119
272c19:dd:c25:c25:dd:dd:dd:111a/1282c19:dd:c25:c25:dd:dd:dd:111a
282c19:dd:c25:c25:dd:dd:dd:111b/1282c19:dd:c25:c25:dd:dd:dd:111b
292c19:dd:c25:c25:dd:dd:dd:111c/1282c19:dd:c25:c25:dd:dd:dd:111c
302c19:dd:c25:c25:dd:dd:dd:111d/1282c19:dd:c25:c25:dd:dd:dd:111d
312c19:dd:c25:c25:dd:dd:dd:111e/1282c19:dd:c25:c25:dd:dd:dd:111e
322c19:dd:c25:c25:dd:dd:dd:111f/1282c19:dd:c25:c25:dd:dd:dd:111f
332c19:dd:c25:c25:dd:dd:dd:1120/1282c19:dd:c25:c25:dd:dd:dd:1120
342c19:dd:c25:c25:dd:dd:dd:1121/1282c19:dd:c25:c25:dd:dd:dd:1121
352c19:dd:c25:c25:dd:dd:dd:1122/1282c19:dd:c25:c25:dd:dd:dd:1122
362c19:dd:c25:c25:dd:dd:dd:1123/1282c19:dd:c25:c25:dd:dd:dd:1123
372c19:dd:c25:c25:dd:dd:dd:1124/1282c19:dd:c25:c25:dd:dd:dd:1124
382c19:dd:c25:c25:dd:dd:dd:1125/1282c19:dd:c25:c25:dd:dd:dd:1125
392c19:dd:c25:c25:dd:dd:dd:1126/1282c19:dd:c25:c25:dd:dd:dd:1126
402c19:dd:c25:c25:dd:dd:dd:1127/1282c19:dd:c25:c25:dd:dd:dd:1127
412c19:dd:c25:c25:dd:dd:dd:1128/1282c19:dd:c25:c25:dd:dd:dd:1128
422c19:dd:c25:c25:dd:dd:dd:1129/1282c19:dd:c25:c25:dd:dd:dd:1129
432c19:dd:c25:c25:dd:dd:dd:112a/1282c19:dd:c25:c25:dd:dd:dd:112a
442c19:dd:c25:c25:dd:dd:dd:112b/1282c19:dd:c25:c25:dd:dd:dd:112b
452c19:dd:c25:c25:dd:dd:dd:112c/1282c19:dd:c25:c25:dd:dd:dd:112c
462c19:dd:c25:c25:dd:dd:dd:112d/1282c19:dd:c25:c25:dd:dd:dd:112d
472c19:dd:c25:c25:dd:dd:dd:112e/1282c19:dd:c25:c25:dd:dd:dd:112e
482c19:dd:c25:c25:dd:dd:dd:112f/1282c19:dd:c25:c25:dd:dd:dd:112f
492c19:dd:c25:c25:dd:dd:dd:1130/1282c19:dd:c25:c25:dd:dd:dd:1130
502c19:dd:c25:c25:dd:dd:dd:1131/1282c19:dd:c25:c25:dd:dd:dd:1131
512c19:dd:c25:c25:dd:dd:dd:1132/1282c19:dd:c25:c25:dd:dd:dd:1132
522c19:dd:c25:c25:dd:dd:dd:1133/1282c19:dd:c25:c25:dd:dd:dd:1133
532c19:dd:c25:c25:dd:dd:dd:1134/1282c19:dd:c25:c25:dd:dd:dd:1134
542c19:dd:c25:c25:dd:dd:dd:1135/1282c19:dd:c25:c25:dd:dd:dd:1135
552c19:dd:c25:c25:dd:dd:dd:1136/1282c19:dd:c25:c25:dd:dd:dd:1136
562c19:dd:c25:c25:dd:dd:dd:1137/1282c19:dd:c25:c25:dd:dd:dd:1137
572c19:dd:c25:c25:dd:dd:dd:1138/1282c19:dd:c25:c25:dd:dd:dd:1138
582c19:dd:c25:c25:dd:dd:dd:1139/1282c19:dd:c25:c25:dd:dd:dd:1139
592c19:dd:c25:c25:dd:dd:dd:113a/1282c19:dd:c25:c25:dd:dd:dd:113a
602c19:dd:c25:c25:dd:dd:dd:113b/1282c19:dd:c25:c25:dd:dd:dd:113b
612c19:dd:c25:c25:dd:dd:dd:113c/1282c19:dd:c25:c25:dd:dd:dd:113c
622c19:dd:c25:c25:dd:dd:dd:113d/1282c19:dd:c25:c25:dd:dd:dd:113d
632c19:dd:c25:c25:dd:dd:dd:113e/1282c19:dd:c25:c25:dd:dd:dd:113e
642c19:dd:c25:c25:dd:dd:dd:113f/1282c19:dd:c25:c25:dd:dd:dd:113f
652c19:dd:c25:c25:dd:dd:dd:1140/1282c19:dd:c25:c25:dd:dd:dd:1140
662c19:dd:c25:c25:dd:dd:dd:1141/1282c19:dd:c25:c25:dd:dd:dd:1141
672c19:dd:c25:c25:dd:dd:dd:1142/1282c19:dd:c25:c25:dd:dd:dd:1142
682c19:dd:c25:c25:dd:dd:dd:1143/1282c19:dd:c25:c25:dd:dd:dd:1143
692c19:dd:c25:c25:dd:dd:dd:1144/1282c19:dd:c25:c25:dd:dd:dd:1144
702c19:dd:c25:c25:dd:dd:dd:1145/1282c19:dd:c25:c25:dd:dd:dd:1145
712c19:dd:c25:c25:dd:dd:dd:1146/1282c19:dd:c25:c25:dd:dd:dd:1146
722c19:dd:c25:c25:dd:dd:dd:1147/1282c19:dd:c25:c25:dd:dd:dd:1147
732c19:dd:c25:c25:dd:dd:dd:1148/1282c19:dd:c25:c25:dd:dd:dd:1148
742c19:dd:c25:c25:dd:dd:dd:1149/1282c19:dd:c25:c25:dd:dd:dd:1149
752c19:dd:c25:c25:dd:dd:dd:114a/1282c19:dd:c25:c25:dd:dd:dd:114a
762c19:dd:c25:c25:dd:dd:dd:114b/1282c19:dd:c25:c25:dd:dd:dd:114b
772c19:dd:c25:c25:dd:dd:dd:114c/1282c19:dd:c25:c25:dd:dd:dd:114c
782c19:dd:c25:c25:dd:dd:dd:114d/1282c19:dd:c25:c25:dd:dd:dd:114d
792c19:dd:c25:c25:dd:dd:dd:114e/1282c19:dd:c25:c25:dd:dd:dd:114e
802c19:dd:c25:c25:dd:dd:dd:114f/1282c19:dd:c25:c25:dd:dd:dd:114f
812c19:dd:c25:c25:dd:dd:dd:1150/1282c19:dd:c25:c25:dd:dd:dd:1150
822c19:dd:c25:c25:dd:dd:dd:1151/1282c19:dd:c25:c25:dd:dd:dd:1151
832c19:dd:c25:c25:dd:dd:dd:1152/1282c19:dd:c25:c25:dd:dd:dd:1152
842c19:dd:c25:c25:dd:dd:dd:1153/1282c19:dd:c25:c25:dd:dd:dd:1153
852c19:dd:c25:c25:dd:dd:dd:1154/1282c19:dd:c25:c25:dd:dd:dd:1154
862c19:dd:c25:c25:dd:dd:dd:1155/1282c19:dd:c25:c25:dd:dd:dd:1155
872c19:dd:c25:c25:dd:dd:dd:1156/1282c19:dd:c25:c25:dd:dd:dd:1156
882c19:dd:c25:c25:dd:dd:dd:1157/1282c19:dd:c25:c25:dd:dd:dd:1157
892c19:dd:c25:c25:dd:dd:dd:1158/1282c19:dd:c25:c25:dd:dd:dd:1158
902c19:dd:c25:c25:dd:dd:dd:1159/1282c19:dd:c25:c25:dd:dd:dd:1159
912c19:dd:c25:c25:dd:dd:dd:115a/1282c19:dd:c25:c25:dd:dd:dd:115a
922c19:dd:c25:c25:dd:dd:dd:115b/1282c19:dd:c25:c25:dd:dd:dd:115b
932c19:dd:c25:c25:dd:dd:dd:115c/1282c19:dd:c25:c25:dd:dd:dd:115c
942c19:dd:c25:c25:dd:dd:dd:115d/1282c19:dd:c25:c25:dd:dd:dd:115d
952c19:dd:c25:c25:dd:dd:dd:115e/1282c19:dd:c25:c25:dd:dd:dd:115e
962c19:dd:c25:c25:dd:dd:dd:115f/1282c19:dd:c25:c25:dd:dd:dd:115f
972c19:dd:c25:c25:dd:dd:dd:1160/1282c19:dd:c25:c25:dd:dd:dd:1160
982c19:dd:c25:c25:dd:dd:dd:1161/1282c19:dd:c25:c25:dd:dd:dd:1161
992c19:dd:c25:c25:dd:dd:dd:1162/1282c19:dd:c25:c25:dd:dd:dd:1162
1002c19:dd:c25:c25:dd:dd:dd:1163/1282c19:dd:c25:c25:dd:dd:dd:1163
1012c19:dd:c25:c25:dd:dd:dd:1164/1282c19:dd:c25:c25:dd:dd:dd:1164
1022c19:dd:c25:c25:dd:dd:dd:1165/1282c19:dd:c25:c25:dd:dd:dd:1165
1032c19:dd:c25:c25:dd:dd:dd:1166/1282c19:dd:c25:c25:dd:dd:dd:1166
1042c19:dd:c25:c25:dd:dd:dd:1167/1282c19:dd:c25:c25:dd:dd:dd:1167
1052c19:dd:c25:c25:dd:dd:dd:1168/1282c19:dd:c25:c25:dd:dd:dd:1168
1062c19:dd:c25:c25:dd:dd:dd:1169/1282c19:dd:c25:c25:dd:dd:dd:1169
1072c19:dd:c25:c25:dd:dd:dd:116a/1282c19:dd:c25:c25:dd:dd:dd:116a
1082c19:dd:c25:c25:dd:dd:dd:116b/1282c19:dd:c25:c25:dd:dd:dd:116b
1092c19:dd:c25:c25:dd:dd:dd:116c/1282c19:dd:c25:c25:dd:dd:dd:116c
1102c19:dd:c25:c25:dd:dd:dd:116d/1282c19:dd:c25:c25:dd:dd:dd:116d
1112c19:dd:c25:c25:dd:dd:dd:116e/1282c19:dd:c25:c25:dd:dd:dd:116e
1122c19:dd:c25:c25:dd:dd:dd:116f/1282c19:dd:c25:c25:dd:dd:dd:116f
1132c19:dd:c25:c25:dd:dd:dd:1170/1282c19:dd:c25:c25:dd:dd:dd:1170
1142c19:dd:c25:c25:dd:dd:dd:1171/1282c19:dd:c25:c25:dd:dd:dd:1171
1152c19:dd:c25:c25:dd:dd:dd:1172/1282c19:dd:c25:c25:dd:dd:dd:1172
1162c19:dd:c25:c25:dd:dd:dd:1173/1282c19:dd:c25:c25:dd:dd:dd:1173
1172c19:dd:c25:c25:dd:dd:dd:1174/1282c19:dd:c25:c25:dd:dd:dd:1174
1182c19:dd:c25:c25:dd:dd:dd:1175/1282c19:dd:c25:c25:dd:dd:dd:1175
1192c19:dd:c25:c25:dd:dd:dd:1176/1282c19:dd:c25:c25:dd:dd:dd:1176
1202c19:dd:c25:c25:dd:dd:dd:1177/1282c19:dd:c25:c25:dd:dd:dd:1177
1212c19:dd:c25:c25:dd:dd:dd:1178/1282c19:dd:c25:c25:dd:dd:dd:1178
1222c19:dd:c25:c25:dd:dd:dd:1179/1282c19:dd:c25:c25:dd:dd:dd:1179
1232c19:dd:c25:c25:dd:dd:dd:117a/1282c19:dd:c25:c25:dd:dd:dd:117a
1242c19:dd:c25:c25:dd:dd:dd:117b/1282c19:dd:c25:c25:dd:dd:dd:117b
1252c19:dd:c25:c25:dd:dd:dd:117c/1282c19:dd:c25:c25:dd:dd:dd:117c
1262c19:dd:c25:c25:dd:dd:dd:117d/1282c19:dd:c25:c25:dd:dd:dd:117d
1272c19:dd:c25:c25:dd:dd:dd:117e/1282c19:dd:c25:c25:dd:dd:dd:117e
1282c19:dd:c25:c25:dd:dd:dd:117f/1282c19:dd:c25:c25:dd:dd:dd:117f
1292c19:dd:c25:c25:dd:dd:dd:1180/1282c19:dd:c25:c25:dd:dd:dd:1180
1302c19:dd:c25:c25:dd:dd:dd:1181/1282c19:dd:c25:c25:dd:dd:dd:1181
1312c19:dd:c25:c25:dd:dd:dd:1182/1282c19:dd:c25:c25:dd:dd:dd:1182
1322c19:dd:c25:c25:dd:dd:dd:1183/1282c19:dd:c25:c25:dd:dd:dd:1183
1332c19:dd:c25:c25:dd:dd:dd:1184/1282c19:dd:c25:c25:dd:dd:dd:1184
1342c19:dd:c25:c25:dd:dd:dd:1185/1282c19:dd:c25:c25:dd:dd:dd:1185
1352c19:dd:c25:c25:dd:dd:dd:1186/1282c19:dd:c25:c25:dd:dd:dd:1186
1362c19:dd:c25:c25:dd:dd:dd:1187/1282c19:dd:c25:c25:dd:dd:dd:1187
1372c19:dd:c25:c25:dd:dd:dd:1188/1282c19:dd:c25:c25:dd:dd:dd:1188
1382c19:dd:c25:c25:dd:dd:dd:1189/1282c19:dd:c25:c25:dd:dd:dd:1189
1392c19:dd:c25:c25:dd:dd:dd:118a/1282c19:dd:c25:c25:dd:dd:dd:118a
1402c19:dd:c25:c25:dd:dd:dd:118b/1282c19:dd:c25:c25:dd:dd:dd:118b
1412c19:dd:c25:c25:dd:dd:dd:118c/1282c19:dd:c25:c25:dd:dd:dd:118c
1422c19:dd:c25:c25:dd:dd:dd:118d/1282c19:dd:c25:c25:dd:dd:dd:118d
1432c19:dd:c25:c25:dd:dd:dd:118e/1282c19:dd:c25:c25:dd:dd:dd:118e
1442c19:dd:c25:c25:dd:dd:dd:118f/1282c19:dd:c25:c25:dd:dd:dd:118f
1452c19:dd:c25:c25:dd:dd:dd:1190/1282c19:dd:c25:c25:dd:dd:dd:1190
1462c19:dd:c25:c25:dd:dd:dd:1191/1282c19:dd:c25:c25:dd:dd:dd:1191
1472c19:dd:c25:c25:dd:dd:dd:1192/1282c19:dd:c25:c25:dd:dd:dd:1192
1482c19:dd:c25:c25:dd:dd:dd:1193/1282c19:dd:c25:c25:dd:dd:dd:1193
1492c19:dd:c25:c25:dd:dd:dd:1194/1282c19:dd:c25:c25:dd:dd:dd:1194
1502c19:dd:c25:c25:dd:dd:dd:1195/1282c19:dd:c25:c25:dd:dd:dd:1195
1512c19:dd:c25:c25:dd:dd:dd:1196/1282c19:dd:c25:c25:dd:dd:dd:1196
1522c19:dd:c25:c25:dd:dd:dd:1197/1282c19:dd:c25:c25:dd:dd:dd:1197
1532c19:dd:c25:c25:dd:dd:dd:1198/1282c19:dd:c25:c25:dd:dd:dd:1198
1542c19:dd:c25:c25:dd:dd:dd:1199/1282c19:dd:c25:c25:dd:dd:dd:1199
1552c19:dd:c25:c25:dd:dd:dd:119a/1282c19:dd:c25:c25:dd:dd:dd:119a
1562c19:dd:c25:c25:dd:dd:dd:119b/1282c19:dd:c25:c25:dd:dd:dd:119b
1572c19:dd:c25:c25:dd:dd:dd:119c/1282c19:dd:c25:c25:dd:dd:dd:119c
1582c19:dd:c25:c25:dd:dd:dd:119d/1282c19:dd:c25:c25:dd:dd:dd:119d
1592c19:dd:c25:c25:dd:dd:dd:119e/1282c19:dd:c25:c25:dd:dd:dd:119e
1602c19:dd:c25:c25:dd:dd:dd:119f/1282c19:dd:c25:c25:dd:dd:dd:119f
1612c19:dd:c25:c25:dd:dd:dd:11a0/1282c19:dd:c25:c25:dd:dd:dd:11a0
1622c19:dd:c25:c25:dd:dd:dd:11a1/1282c19:dd:c25:c25:dd:dd:dd:11a1
1632c19:dd:c25:c25:dd:dd:dd:11a2/1282c19:dd:c25:c25:dd:dd:dd:11a2
1642c19:dd:c25:c25:dd:dd:dd:11a3/1282c19:dd:c25:c25:dd:dd:dd:11a3
1652c19:dd:c25:c25:dd:dd:dd:11a4/1282c19:dd:c25:c25:dd:dd:dd:11a4
1662c19:dd:c25:c25:dd:dd:dd:11a5/1282c19:dd:c25:c25:dd:dd:dd:11a5
1672c19:dd:c25:c25:dd:dd:dd:11a6/1282c19:dd:c25:c25:dd:dd:dd:11a6
1682c19:dd:c25:c25:dd:dd:dd:11a7/1282c19:dd:c25:c25:dd:dd:dd:11a7
1692c19:dd:c25:c25:dd:dd:dd:11a8/1282c19:dd:c25:c25:dd:dd:dd:11a8
1702c19:dd:c25:c25:dd:dd:dd:11a9/1282c19:dd:c25:c25:dd:dd:dd:11a9
1712c19:dd:c25:c25:dd:dd:dd:11aa/1282c19:dd:c25:c25:dd:dd:dd:11aa
1722c19:dd:c25:c25:dd:dd:dd:11ab/1282c19:dd:c25:c25:dd:dd:dd:11ab
1732c19:dd:c25:c25:dd:dd:dd:11ac/1282c19:dd:c25:c25:dd:dd:dd:11ac
1742c19:dd:c25:c25:dd:dd:dd:11ad/1282c19:dd:c25:c25:dd:dd:dd:11ad
1752c19:dd:c25:c25:dd:dd:dd:11ae/1282c19:dd:c25:c25:dd:dd:dd:11ae
1762c19:dd:c25:c25:dd:dd:dd:11af/1282c19:dd:c25:c25:dd:dd:dd:11af
1772c19:dd:c25:c25:dd:dd:dd:11b0/1282c19:dd:c25:c25:dd:dd:dd:11b0
1782c19:dd:c25:c25:dd:dd:dd:11b1/1282c19:dd:c25:c25:dd:dd:dd:11b1
1792c19:dd:c25:c25:dd:dd:dd:11b2/1282c19:dd:c25:c25:dd:dd:dd:11b2
1802c19:dd:c25:c25:dd:dd:dd:11b3/1282c19:dd:c25:c25:dd:dd:dd:11b3
1812c19:dd:c25:c25:dd:dd:dd:11b4/1282c19:dd:c25:c25:dd:dd:dd:11b4
1822c19:dd:c25:c25:dd:dd:dd:11b5/1282c19:dd:c25:c25:dd:dd:dd:11b5
1832c19:dd:c25:c25:dd:dd:dd:11b6/1282c19:dd:c25:c25:dd:dd:dd:11b6
1842c19:dd:c25:c25:dd:dd:dd:11b7/1282c19:dd:c25:c25:dd:dd:dd:11b7
1852c19:dd:c25:c25:dd:dd:dd:11b8/1282c19:dd:c25:c25:dd:dd:dd:11b8
1862c19:dd:c25:c25:dd:dd:dd:11b9/1282c19:dd:c25:c25:dd:dd:dd:11b9
1872c19:dd:c25:c25:dd:dd:dd:11ba/1282c19:dd:c25:c25:dd:dd:dd:11ba
1882c19:dd:c25:c25:dd:dd:dd:11bb/1282c19:dd:c25:c25:dd:dd:dd:11bb
1892c19:dd:c25:c25:dd:dd:dd:11bc/1282c19:dd:c25:c25:dd:dd:dd:11bc
1902c19:dd:c25:c25:dd:dd:dd:11bd/1282c19:dd:c25:c25:dd:dd:dd:11bd
1912c19:dd:c25:c25:dd:dd:dd:11be/1282c19:dd:c25:c25:dd:dd:dd:11be
1922c19:dd:c25:c25:dd:dd:dd:11bf/1282c19:dd:c25:c25:dd:dd:dd:11bf
1932c19:dd:c25:c25:dd:dd:dd:11c0/1282c19:dd:c25:c25:dd:dd:dd:11c0
1942c19:dd:c25:c25:dd:dd:dd:11c1/1282c19:dd:c25:c25:dd:dd:dd:11c1
1952c19:dd:c25:c25:dd:dd:dd:11c2/1282c19:dd:c25:c25:dd:dd:dd:11c2
1962c19:dd:c25:c25:dd:dd:dd:11c3/1282c19:dd:c25:c25:dd:dd:dd:11c3
1972c19:dd:c25:c25:dd:dd:dd:11c4/1282c19:dd:c25:c25:dd:dd:dd:11c4
1982c19:dd:c25:c25:dd:dd:dd:11c5/1282c19:dd:c25:c25:dd:dd:dd:11c5
1992c19:dd:c25:c25:dd:dd:dd:11c6/1282c19:dd:c25:c25:dd:dd:dd:11c6
2002c19:dd:c25:c25:dd:dd:dd:11c7/1282c19:dd:c25:c25:dd:dd:dd:11c7
2012c19:dd:c25:c25:dd:dd:dd:11c8/1282c19:dd:c25:c25:dd:dd:dd:11c8
2022c19:dd:c25:c25:dd:dd:dd:11c9/1282c19:dd:c25:c25:dd:dd:dd:11c9
2032c19:dd:c25:c25:dd:dd:dd:11ca/1282c19:dd:c25:c25:dd:dd:dd:11ca
2042c19:dd:c25:c25:dd:dd:dd:11cb/1282c19:dd:c25:c25:dd:dd:dd:11cb
2052c19:dd:c25:c25:dd:dd:dd:11cc/1282c19:dd:c25:c25:dd:dd:dd:11cc
2062c19:dd:c25:c25:dd:dd:dd:11cd/1282c19:dd:c25:c25:dd:dd:dd:11cd
2072c19:dd:c25:c25:dd:dd:dd:11ce/1282c19:dd:c25:c25:dd:dd:dd:11ce
2082c19:dd:c25:c25:dd:dd:dd:11cf/1282c19:dd:c25:c25:dd:dd:dd:11cf
2092c19:dd:c25:c25:dd:dd:dd:11d0/1282c19:dd:c25:c25:dd:dd:dd:11d0
2102c19:dd:c25:c25:dd:dd:dd:11d1/1282c19:dd:c25:c25:dd:dd:dd:11d1
2112c19:dd:c25:c25:dd:dd:dd:11d2/1282c19:dd:c25:c25:dd:dd:dd:11d2
2122c19:dd:c25:c25:dd:dd:dd:11d3/1282c19:dd:c25:c25:dd:dd:dd:11d3
2132c19:dd:c25:c25:dd:dd:dd:11d4/1282c19:dd:c25:c25:dd:dd:dd:11d4
2142c19:dd:c25:c25:dd:dd:dd:11d5/1282c19:dd:c25:c25:dd:dd:dd:11d5
2152c19:dd:c25:c25:dd:dd:dd:11d6/1282c19:dd:c25:c25:dd:dd:dd:11d6
2162c19:dd:c25:c25:dd:dd:dd:11d7/1282c19:dd:c25:c25:dd:dd:dd:11d7
2172c19:dd:c25:c25:dd:dd:dd:11d8/1282c19:dd:c25:c25:dd:dd:dd:11d8
2182c19:dd:c25:c25:dd:dd:dd:11d9/1282c19:dd:c25:c25:dd:dd:dd:11d9
2192c19:dd:c25:c25:dd:dd:dd:11da/1282c19:dd:c25:c25:dd:dd:dd:11da
2202c19:dd:c25:c25:dd:dd:dd:11db/1282c19:dd:c25:c25:dd:dd:dd:11db
2212c19:dd:c25:c25:dd:dd:dd:11dc/1282c19:dd:c25:c25:dd:dd:dd:11dc
2222c19:dd:c25:c25:dd:dd:dd:11dd/1282c19:dd:c25:c25:dd:dd:dd:11dd
2232c19:dd:c25:c25:dd:dd:dd:11de/1282c19:dd:c25:c25:dd:dd:dd:11de
2242c19:dd:c25:c25:dd:dd:dd:11df/1282c19:dd:c25:c25:dd:dd:dd:11df
2252c19:dd:c25:c25:dd:dd:dd:11e0/1282c19:dd:c25:c25:dd:dd:dd:11e0
2262c19:dd:c25:c25:dd:dd:dd:11e1/1282c19:dd:c25:c25:dd:dd:dd:11e1
2272c19:dd:c25:c25:dd:dd:dd:11e2/1282c19:dd:c25:c25:dd:dd:dd:11e2
2282c19:dd:c25:c25:dd:dd:dd:11e3/1282c19:dd:c25:c25:dd:dd:dd:11e3
2292c19:dd:c25:c25:dd:dd:dd:11e4/1282c19:dd:c25:c25:dd:dd:dd:11e4
2302c19:dd:c25:c25:dd:dd:dd:11e5/1282c19:dd:c25:c25:dd:dd:dd:11e5
2312c19:dd:c25:c25:dd:dd:dd:11e6/1282c19:dd:c25:c25:dd:dd:dd:11e6
2322c19:dd:c25:c25:dd:dd:dd:11e7/1282c19:dd:c25:c25:dd:dd:dd:11e7
2332c19:dd:c25:c25:dd:dd:dd:11e8/1282c19:dd:c25:c25:dd:dd:dd:11e8
2342c19:dd:c25:c25:dd:dd:dd:11e9/1282c19:dd:c25:c25:dd:dd:dd:11e9
2352c19:dd:c25:c25:dd:dd:dd:11ea/1282c19:dd:c25:c25:dd:dd:dd:11ea
2362c19:dd:c25:c25:dd:dd:dd:11eb/1282c19:dd:c25:c25:dd:dd:dd:11eb
2372c19:dd:c25:c25:dd:dd:dd:11ec/1282c19:dd:c25:c25:dd:dd:dd:11ec
2382c19:dd:c25:c25:dd:dd:dd:11ed/1282c19:dd:c25:c25:dd:dd:dd:11ed
2392c19:dd:c25:c25:dd:dd:dd:11ee/1282c19:dd:c25:c25:dd:dd:dd:11ee
2402c19:dd:c25:c25:dd:dd:dd:11ef/1282c19:dd:c25:c25:dd:dd:dd:11ef
2412c19:dd:c25:c25:dd:dd:dd:11f0/1282c19:dd:c25:c25:dd:dd:dd:11f0
2422c19:dd:c25:c25:dd:dd:dd:11f1/1282c19:dd:c25:c25:dd:dd:dd:11f1
2432c19:dd:c25:c25:dd:dd:dd:11f2/1282c19:dd:c25:c25:dd:dd:dd:11f2
2442c19:dd:c25:c25:dd:dd:dd:11f3/1282c19:dd:c25:c25:dd:dd:dd:11f3
2452c19:dd:c25:c25:dd:dd:dd:11f4/1282c19:dd:c25:c25:dd:dd:dd:11f4
2462c19:dd:c25:c25:dd:dd:dd:11f5/1282c19:dd:c25:c25:dd:dd:dd:11f5
2472c19:dd:c25:c25:dd:dd:dd:11f6/1282c19:dd:c25:c25:dd:dd:dd:11f6
2482c19:dd:c25:c25:dd:dd:dd:11f7/1282c19:dd:c25:c25:dd:dd:dd:11f7
2492c19:dd:c25:c25:dd:dd:dd:11f8/1282c19:dd:c25:c25:dd:dd:dd:11f8
2502c19:dd:c25:c25:dd:dd:dd:11f9/1282c19:dd:c25:c25:dd:dd:dd:11f9
2512c19:dd:c25:c25:dd:dd:dd:11fa/1282c19:dd:c25:c25:dd:dd:dd:11fa
2522c19:dd:c25:c25:dd:dd:dd:11fb/1282c19:dd:c25:c25:dd:dd:dd:11fb
2532c19:dd:c25:c25:dd:dd:dd:11fc/1282c19:dd:c25:c25:dd:dd:dd:11fc
2542c19:dd:c25:c25:dd:dd:dd:11fd/1282c19:dd:c25:c25:dd:dd:dd:11fd
2552c19:dd:c25:c25:dd:dd:dd:11fe/1282c19:dd:c25:c25:dd:dd:dd:11fe
2562c19:dd:c25:c25:dd:dd:dd:11ff/1282c19:dd:c25:c25:dd:dd:dd:11ff

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.