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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:2100/120
First address
2c19:dd:d9:dd:c25:c25:94de:2100
Last address
2c19:dd:d9:dd:c25:c25:94de:21ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:2100
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
1.2.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:2100/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:2100/1282c19:dd:d9:dd:c25:c25:94de:2100
22c19:dd:d9:dd:c25:c25:94de:2101/1282c19:dd:d9:dd:c25:c25:94de:2101
32c19:dd:d9:dd:c25:c25:94de:2102/1282c19:dd:d9:dd:c25:c25:94de:2102
42c19:dd:d9:dd:c25:c25:94de:2103/1282c19:dd:d9:dd:c25:c25:94de:2103
52c19:dd:d9:dd:c25:c25:94de:2104/1282c19:dd:d9:dd:c25:c25:94de:2104
62c19:dd:d9:dd:c25:c25:94de:2105/1282c19:dd:d9:dd:c25:c25:94de:2105
72c19:dd:d9:dd:c25:c25:94de:2106/1282c19:dd:d9:dd:c25:c25:94de:2106
82c19:dd:d9:dd:c25:c25:94de:2107/1282c19:dd:d9:dd:c25:c25:94de:2107
92c19:dd:d9:dd:c25:c25:94de:2108/1282c19:dd:d9:dd:c25:c25:94de:2108
102c19:dd:d9:dd:c25:c25:94de:2109/1282c19:dd:d9:dd:c25:c25:94de:2109
112c19:dd:d9:dd:c25:c25:94de:210a/1282c19:dd:d9:dd:c25:c25:94de:210a
122c19:dd:d9:dd:c25:c25:94de:210b/1282c19:dd:d9:dd:c25:c25:94de:210b
132c19:dd:d9:dd:c25:c25:94de:210c/1282c19:dd:d9:dd:c25:c25:94de:210c
142c19:dd:d9:dd:c25:c25:94de:210d/1282c19:dd:d9:dd:c25:c25:94de:210d
152c19:dd:d9:dd:c25:c25:94de:210e/1282c19:dd:d9:dd:c25:c25:94de:210e
162c19:dd:d9:dd:c25:c25:94de:210f/1282c19:dd:d9:dd:c25:c25:94de:210f
172c19:dd:d9:dd:c25:c25:94de:2110/1282c19:dd:d9:dd:c25:c25:94de:2110
182c19:dd:d9:dd:c25:c25:94de:2111/1282c19:dd:d9:dd:c25:c25:94de:2111
192c19:dd:d9:dd:c25:c25:94de:2112/1282c19:dd:d9:dd:c25:c25:94de:2112
202c19:dd:d9:dd:c25:c25:94de:2113/1282c19:dd:d9:dd:c25:c25:94de:2113
212c19:dd:d9:dd:c25:c25:94de:2114/1282c19:dd:d9:dd:c25:c25:94de:2114
222c19:dd:d9:dd:c25:c25:94de:2115/1282c19:dd:d9:dd:c25:c25:94de:2115
232c19:dd:d9:dd:c25:c25:94de:2116/1282c19:dd:d9:dd:c25:c25:94de:2116
242c19:dd:d9:dd:c25:c25:94de:2117/1282c19:dd:d9:dd:c25:c25:94de:2117
252c19:dd:d9:dd:c25:c25:94de:2118/1282c19:dd:d9:dd:c25:c25:94de:2118
262c19:dd:d9:dd:c25:c25:94de:2119/1282c19:dd:d9:dd:c25:c25:94de:2119
272c19:dd:d9:dd:c25:c25:94de:211a/1282c19:dd:d9:dd:c25:c25:94de:211a
282c19:dd:d9:dd:c25:c25:94de:211b/1282c19:dd:d9:dd:c25:c25:94de:211b
292c19:dd:d9:dd:c25:c25:94de:211c/1282c19:dd:d9:dd:c25:c25:94de:211c
302c19:dd:d9:dd:c25:c25:94de:211d/1282c19:dd:d9:dd:c25:c25:94de:211d
312c19:dd:d9:dd:c25:c25:94de:211e/1282c19:dd:d9:dd:c25:c25:94de:211e
322c19:dd:d9:dd:c25:c25:94de:211f/1282c19:dd:d9:dd:c25:c25:94de:211f
332c19:dd:d9:dd:c25:c25:94de:2120/1282c19:dd:d9:dd:c25:c25:94de:2120
342c19:dd:d9:dd:c25:c25:94de:2121/1282c19:dd:d9:dd:c25:c25:94de:2121
352c19:dd:d9:dd:c25:c25:94de:2122/1282c19:dd:d9:dd:c25:c25:94de:2122
362c19:dd:d9:dd:c25:c25:94de:2123/1282c19:dd:d9:dd:c25:c25:94de:2123
372c19:dd:d9:dd:c25:c25:94de:2124/1282c19:dd:d9:dd:c25:c25:94de:2124
382c19:dd:d9:dd:c25:c25:94de:2125/1282c19:dd:d9:dd:c25:c25:94de:2125
392c19:dd:d9:dd:c25:c25:94de:2126/1282c19:dd:d9:dd:c25:c25:94de:2126
402c19:dd:d9:dd:c25:c25:94de:2127/1282c19:dd:d9:dd:c25:c25:94de:2127
412c19:dd:d9:dd:c25:c25:94de:2128/1282c19:dd:d9:dd:c25:c25:94de:2128
422c19:dd:d9:dd:c25:c25:94de:2129/1282c19:dd:d9:dd:c25:c25:94de:2129
432c19:dd:d9:dd:c25:c25:94de:212a/1282c19:dd:d9:dd:c25:c25:94de:212a
442c19:dd:d9:dd:c25:c25:94de:212b/1282c19:dd:d9:dd:c25:c25:94de:212b
452c19:dd:d9:dd:c25:c25:94de:212c/1282c19:dd:d9:dd:c25:c25:94de:212c
462c19:dd:d9:dd:c25:c25:94de:212d/1282c19:dd:d9:dd:c25:c25:94de:212d
472c19:dd:d9:dd:c25:c25:94de:212e/1282c19:dd:d9:dd:c25:c25:94de:212e
482c19:dd:d9:dd:c25:c25:94de:212f/1282c19:dd:d9:dd:c25:c25:94de:212f
492c19:dd:d9:dd:c25:c25:94de:2130/1282c19:dd:d9:dd:c25:c25:94de:2130
502c19:dd:d9:dd:c25:c25:94de:2131/1282c19:dd:d9:dd:c25:c25:94de:2131
512c19:dd:d9:dd:c25:c25:94de:2132/1282c19:dd:d9:dd:c25:c25:94de:2132
522c19:dd:d9:dd:c25:c25:94de:2133/1282c19:dd:d9:dd:c25:c25:94de:2133
532c19:dd:d9:dd:c25:c25:94de:2134/1282c19:dd:d9:dd:c25:c25:94de:2134
542c19:dd:d9:dd:c25:c25:94de:2135/1282c19:dd:d9:dd:c25:c25:94de:2135
552c19:dd:d9:dd:c25:c25:94de:2136/1282c19:dd:d9:dd:c25:c25:94de:2136
562c19:dd:d9:dd:c25:c25:94de:2137/1282c19:dd:d9:dd:c25:c25:94de:2137
572c19:dd:d9:dd:c25:c25:94de:2138/1282c19:dd:d9:dd:c25:c25:94de:2138
582c19:dd:d9:dd:c25:c25:94de:2139/1282c19:dd:d9:dd:c25:c25:94de:2139
592c19:dd:d9:dd:c25:c25:94de:213a/1282c19:dd:d9:dd:c25:c25:94de:213a
602c19:dd:d9:dd:c25:c25:94de:213b/1282c19:dd:d9:dd:c25:c25:94de:213b
612c19:dd:d9:dd:c25:c25:94de:213c/1282c19:dd:d9:dd:c25:c25:94de:213c
622c19:dd:d9:dd:c25:c25:94de:213d/1282c19:dd:d9:dd:c25:c25:94de:213d
632c19:dd:d9:dd:c25:c25:94de:213e/1282c19:dd:d9:dd:c25:c25:94de:213e
642c19:dd:d9:dd:c25:c25:94de:213f/1282c19:dd:d9:dd:c25:c25:94de:213f
652c19:dd:d9:dd:c25:c25:94de:2140/1282c19:dd:d9:dd:c25:c25:94de:2140
662c19:dd:d9:dd:c25:c25:94de:2141/1282c19:dd:d9:dd:c25:c25:94de:2141
672c19:dd:d9:dd:c25:c25:94de:2142/1282c19:dd:d9:dd:c25:c25:94de:2142
682c19:dd:d9:dd:c25:c25:94de:2143/1282c19:dd:d9:dd:c25:c25:94de:2143
692c19:dd:d9:dd:c25:c25:94de:2144/1282c19:dd:d9:dd:c25:c25:94de:2144
702c19:dd:d9:dd:c25:c25:94de:2145/1282c19:dd:d9:dd:c25:c25:94de:2145
712c19:dd:d9:dd:c25:c25:94de:2146/1282c19:dd:d9:dd:c25:c25:94de:2146
722c19:dd:d9:dd:c25:c25:94de:2147/1282c19:dd:d9:dd:c25:c25:94de:2147
732c19:dd:d9:dd:c25:c25:94de:2148/1282c19:dd:d9:dd:c25:c25:94de:2148
742c19:dd:d9:dd:c25:c25:94de:2149/1282c19:dd:d9:dd:c25:c25:94de:2149
752c19:dd:d9:dd:c25:c25:94de:214a/1282c19:dd:d9:dd:c25:c25:94de:214a
762c19:dd:d9:dd:c25:c25:94de:214b/1282c19:dd:d9:dd:c25:c25:94de:214b
772c19:dd:d9:dd:c25:c25:94de:214c/1282c19:dd:d9:dd:c25:c25:94de:214c
782c19:dd:d9:dd:c25:c25:94de:214d/1282c19:dd:d9:dd:c25:c25:94de:214d
792c19:dd:d9:dd:c25:c25:94de:214e/1282c19:dd:d9:dd:c25:c25:94de:214e
802c19:dd:d9:dd:c25:c25:94de:214f/1282c19:dd:d9:dd:c25:c25:94de:214f
812c19:dd:d9:dd:c25:c25:94de:2150/1282c19:dd:d9:dd:c25:c25:94de:2150
822c19:dd:d9:dd:c25:c25:94de:2151/1282c19:dd:d9:dd:c25:c25:94de:2151
832c19:dd:d9:dd:c25:c25:94de:2152/1282c19:dd:d9:dd:c25:c25:94de:2152
842c19:dd:d9:dd:c25:c25:94de:2153/1282c19:dd:d9:dd:c25:c25:94de:2153
852c19:dd:d9:dd:c25:c25:94de:2154/1282c19:dd:d9:dd:c25:c25:94de:2154
862c19:dd:d9:dd:c25:c25:94de:2155/1282c19:dd:d9:dd:c25:c25:94de:2155
872c19:dd:d9:dd:c25:c25:94de:2156/1282c19:dd:d9:dd:c25:c25:94de:2156
882c19:dd:d9:dd:c25:c25:94de:2157/1282c19:dd:d9:dd:c25:c25:94de:2157
892c19:dd:d9:dd:c25:c25:94de:2158/1282c19:dd:d9:dd:c25:c25:94de:2158
902c19:dd:d9:dd:c25:c25:94de:2159/1282c19:dd:d9:dd:c25:c25:94de:2159
912c19:dd:d9:dd:c25:c25:94de:215a/1282c19:dd:d9:dd:c25:c25:94de:215a
922c19:dd:d9:dd:c25:c25:94de:215b/1282c19:dd:d9:dd:c25:c25:94de:215b
932c19:dd:d9:dd:c25:c25:94de:215c/1282c19:dd:d9:dd:c25:c25:94de:215c
942c19:dd:d9:dd:c25:c25:94de:215d/1282c19:dd:d9:dd:c25:c25:94de:215d
952c19:dd:d9:dd:c25:c25:94de:215e/1282c19:dd:d9:dd:c25:c25:94de:215e
962c19:dd:d9:dd:c25:c25:94de:215f/1282c19:dd:d9:dd:c25:c25:94de:215f
972c19:dd:d9:dd:c25:c25:94de:2160/1282c19:dd:d9:dd:c25:c25:94de:2160
982c19:dd:d9:dd:c25:c25:94de:2161/1282c19:dd:d9:dd:c25:c25:94de:2161
992c19:dd:d9:dd:c25:c25:94de:2162/1282c19:dd:d9:dd:c25:c25:94de:2162
1002c19:dd:d9:dd:c25:c25:94de:2163/1282c19:dd:d9:dd:c25:c25:94de:2163
1012c19:dd:d9:dd:c25:c25:94de:2164/1282c19:dd:d9:dd:c25:c25:94de:2164
1022c19:dd:d9:dd:c25:c25:94de:2165/1282c19:dd:d9:dd:c25:c25:94de:2165
1032c19:dd:d9:dd:c25:c25:94de:2166/1282c19:dd:d9:dd:c25:c25:94de:2166
1042c19:dd:d9:dd:c25:c25:94de:2167/1282c19:dd:d9:dd:c25:c25:94de:2167
1052c19:dd:d9:dd:c25:c25:94de:2168/1282c19:dd:d9:dd:c25:c25:94de:2168
1062c19:dd:d9:dd:c25:c25:94de:2169/1282c19:dd:d9:dd:c25:c25:94de:2169
1072c19:dd:d9:dd:c25:c25:94de:216a/1282c19:dd:d9:dd:c25:c25:94de:216a
1082c19:dd:d9:dd:c25:c25:94de:216b/1282c19:dd:d9:dd:c25:c25:94de:216b
1092c19:dd:d9:dd:c25:c25:94de:216c/1282c19:dd:d9:dd:c25:c25:94de:216c
1102c19:dd:d9:dd:c25:c25:94de:216d/1282c19:dd:d9:dd:c25:c25:94de:216d
1112c19:dd:d9:dd:c25:c25:94de:216e/1282c19:dd:d9:dd:c25:c25:94de:216e
1122c19:dd:d9:dd:c25:c25:94de:216f/1282c19:dd:d9:dd:c25:c25:94de:216f
1132c19:dd:d9:dd:c25:c25:94de:2170/1282c19:dd:d9:dd:c25:c25:94de:2170
1142c19:dd:d9:dd:c25:c25:94de:2171/1282c19:dd:d9:dd:c25:c25:94de:2171
1152c19:dd:d9:dd:c25:c25:94de:2172/1282c19:dd:d9:dd:c25:c25:94de:2172
1162c19:dd:d9:dd:c25:c25:94de:2173/1282c19:dd:d9:dd:c25:c25:94de:2173
1172c19:dd:d9:dd:c25:c25:94de:2174/1282c19:dd:d9:dd:c25:c25:94de:2174
1182c19:dd:d9:dd:c25:c25:94de:2175/1282c19:dd:d9:dd:c25:c25:94de:2175
1192c19:dd:d9:dd:c25:c25:94de:2176/1282c19:dd:d9:dd:c25:c25:94de:2176
1202c19:dd:d9:dd:c25:c25:94de:2177/1282c19:dd:d9:dd:c25:c25:94de:2177
1212c19:dd:d9:dd:c25:c25:94de:2178/1282c19:dd:d9:dd:c25:c25:94de:2178
1222c19:dd:d9:dd:c25:c25:94de:2179/1282c19:dd:d9:dd:c25:c25:94de:2179
1232c19:dd:d9:dd:c25:c25:94de:217a/1282c19:dd:d9:dd:c25:c25:94de:217a
1242c19:dd:d9:dd:c25:c25:94de:217b/1282c19:dd:d9:dd:c25:c25:94de:217b
1252c19:dd:d9:dd:c25:c25:94de:217c/1282c19:dd:d9:dd:c25:c25:94de:217c
1262c19:dd:d9:dd:c25:c25:94de:217d/1282c19:dd:d9:dd:c25:c25:94de:217d
1272c19:dd:d9:dd:c25:c25:94de:217e/1282c19:dd:d9:dd:c25:c25:94de:217e
1282c19:dd:d9:dd:c25:c25:94de:217f/1282c19:dd:d9:dd:c25:c25:94de:217f
1292c19:dd:d9:dd:c25:c25:94de:2180/1282c19:dd:d9:dd:c25:c25:94de:2180
1302c19:dd:d9:dd:c25:c25:94de:2181/1282c19:dd:d9:dd:c25:c25:94de:2181
1312c19:dd:d9:dd:c25:c25:94de:2182/1282c19:dd:d9:dd:c25:c25:94de:2182
1322c19:dd:d9:dd:c25:c25:94de:2183/1282c19:dd:d9:dd:c25:c25:94de:2183
1332c19:dd:d9:dd:c25:c25:94de:2184/1282c19:dd:d9:dd:c25:c25:94de:2184
1342c19:dd:d9:dd:c25:c25:94de:2185/1282c19:dd:d9:dd:c25:c25:94de:2185
1352c19:dd:d9:dd:c25:c25:94de:2186/1282c19:dd:d9:dd:c25:c25:94de:2186
1362c19:dd:d9:dd:c25:c25:94de:2187/1282c19:dd:d9:dd:c25:c25:94de:2187
1372c19:dd:d9:dd:c25:c25:94de:2188/1282c19:dd:d9:dd:c25:c25:94de:2188
1382c19:dd:d9:dd:c25:c25:94de:2189/1282c19:dd:d9:dd:c25:c25:94de:2189
1392c19:dd:d9:dd:c25:c25:94de:218a/1282c19:dd:d9:dd:c25:c25:94de:218a
1402c19:dd:d9:dd:c25:c25:94de:218b/1282c19:dd:d9:dd:c25:c25:94de:218b
1412c19:dd:d9:dd:c25:c25:94de:218c/1282c19:dd:d9:dd:c25:c25:94de:218c
1422c19:dd:d9:dd:c25:c25:94de:218d/1282c19:dd:d9:dd:c25:c25:94de:218d
1432c19:dd:d9:dd:c25:c25:94de:218e/1282c19:dd:d9:dd:c25:c25:94de:218e
1442c19:dd:d9:dd:c25:c25:94de:218f/1282c19:dd:d9:dd:c25:c25:94de:218f
1452c19:dd:d9:dd:c25:c25:94de:2190/1282c19:dd:d9:dd:c25:c25:94de:2190
1462c19:dd:d9:dd:c25:c25:94de:2191/1282c19:dd:d9:dd:c25:c25:94de:2191
1472c19:dd:d9:dd:c25:c25:94de:2192/1282c19:dd:d9:dd:c25:c25:94de:2192
1482c19:dd:d9:dd:c25:c25:94de:2193/1282c19:dd:d9:dd:c25:c25:94de:2193
1492c19:dd:d9:dd:c25:c25:94de:2194/1282c19:dd:d9:dd:c25:c25:94de:2194
1502c19:dd:d9:dd:c25:c25:94de:2195/1282c19:dd:d9:dd:c25:c25:94de:2195
1512c19:dd:d9:dd:c25:c25:94de:2196/1282c19:dd:d9:dd:c25:c25:94de:2196
1522c19:dd:d9:dd:c25:c25:94de:2197/1282c19:dd:d9:dd:c25:c25:94de:2197
1532c19:dd:d9:dd:c25:c25:94de:2198/1282c19:dd:d9:dd:c25:c25:94de:2198
1542c19:dd:d9:dd:c25:c25:94de:2199/1282c19:dd:d9:dd:c25:c25:94de:2199
1552c19:dd:d9:dd:c25:c25:94de:219a/1282c19:dd:d9:dd:c25:c25:94de:219a
1562c19:dd:d9:dd:c25:c25:94de:219b/1282c19:dd:d9:dd:c25:c25:94de:219b
1572c19:dd:d9:dd:c25:c25:94de:219c/1282c19:dd:d9:dd:c25:c25:94de:219c
1582c19:dd:d9:dd:c25:c25:94de:219d/1282c19:dd:d9:dd:c25:c25:94de:219d
1592c19:dd:d9:dd:c25:c25:94de:219e/1282c19:dd:d9:dd:c25:c25:94de:219e
1602c19:dd:d9:dd:c25:c25:94de:219f/1282c19:dd:d9:dd:c25:c25:94de:219f
1612c19:dd:d9:dd:c25:c25:94de:21a0/1282c19:dd:d9:dd:c25:c25:94de:21a0
1622c19:dd:d9:dd:c25:c25:94de:21a1/1282c19:dd:d9:dd:c25:c25:94de:21a1
1632c19:dd:d9:dd:c25:c25:94de:21a2/1282c19:dd:d9:dd:c25:c25:94de:21a2
1642c19:dd:d9:dd:c25:c25:94de:21a3/1282c19:dd:d9:dd:c25:c25:94de:21a3
1652c19:dd:d9:dd:c25:c25:94de:21a4/1282c19:dd:d9:dd:c25:c25:94de:21a4
1662c19:dd:d9:dd:c25:c25:94de:21a5/1282c19:dd:d9:dd:c25:c25:94de:21a5
1672c19:dd:d9:dd:c25:c25:94de:21a6/1282c19:dd:d9:dd:c25:c25:94de:21a6
1682c19:dd:d9:dd:c25:c25:94de:21a7/1282c19:dd:d9:dd:c25:c25:94de:21a7
1692c19:dd:d9:dd:c25:c25:94de:21a8/1282c19:dd:d9:dd:c25:c25:94de:21a8
1702c19:dd:d9:dd:c25:c25:94de:21a9/1282c19:dd:d9:dd:c25:c25:94de:21a9
1712c19:dd:d9:dd:c25:c25:94de:21aa/1282c19:dd:d9:dd:c25:c25:94de:21aa
1722c19:dd:d9:dd:c25:c25:94de:21ab/1282c19:dd:d9:dd:c25:c25:94de:21ab
1732c19:dd:d9:dd:c25:c25:94de:21ac/1282c19:dd:d9:dd:c25:c25:94de:21ac
1742c19:dd:d9:dd:c25:c25:94de:21ad/1282c19:dd:d9:dd:c25:c25:94de:21ad
1752c19:dd:d9:dd:c25:c25:94de:21ae/1282c19:dd:d9:dd:c25:c25:94de:21ae
1762c19:dd:d9:dd:c25:c25:94de:21af/1282c19:dd:d9:dd:c25:c25:94de:21af
1772c19:dd:d9:dd:c25:c25:94de:21b0/1282c19:dd:d9:dd:c25:c25:94de:21b0
1782c19:dd:d9:dd:c25:c25:94de:21b1/1282c19:dd:d9:dd:c25:c25:94de:21b1
1792c19:dd:d9:dd:c25:c25:94de:21b2/1282c19:dd:d9:dd:c25:c25:94de:21b2
1802c19:dd:d9:dd:c25:c25:94de:21b3/1282c19:dd:d9:dd:c25:c25:94de:21b3
1812c19:dd:d9:dd:c25:c25:94de:21b4/1282c19:dd:d9:dd:c25:c25:94de:21b4
1822c19:dd:d9:dd:c25:c25:94de:21b5/1282c19:dd:d9:dd:c25:c25:94de:21b5
1832c19:dd:d9:dd:c25:c25:94de:21b6/1282c19:dd:d9:dd:c25:c25:94de:21b6
1842c19:dd:d9:dd:c25:c25:94de:21b7/1282c19:dd:d9:dd:c25:c25:94de:21b7
1852c19:dd:d9:dd:c25:c25:94de:21b8/1282c19:dd:d9:dd:c25:c25:94de:21b8
1862c19:dd:d9:dd:c25:c25:94de:21b9/1282c19:dd:d9:dd:c25:c25:94de:21b9
1872c19:dd:d9:dd:c25:c25:94de:21ba/1282c19:dd:d9:dd:c25:c25:94de:21ba
1882c19:dd:d9:dd:c25:c25:94de:21bb/1282c19:dd:d9:dd:c25:c25:94de:21bb
1892c19:dd:d9:dd:c25:c25:94de:21bc/1282c19:dd:d9:dd:c25:c25:94de:21bc
1902c19:dd:d9:dd:c25:c25:94de:21bd/1282c19:dd:d9:dd:c25:c25:94de:21bd
1912c19:dd:d9:dd:c25:c25:94de:21be/1282c19:dd:d9:dd:c25:c25:94de:21be
1922c19:dd:d9:dd:c25:c25:94de:21bf/1282c19:dd:d9:dd:c25:c25:94de:21bf
1932c19:dd:d9:dd:c25:c25:94de:21c0/1282c19:dd:d9:dd:c25:c25:94de:21c0
1942c19:dd:d9:dd:c25:c25:94de:21c1/1282c19:dd:d9:dd:c25:c25:94de:21c1
1952c19:dd:d9:dd:c25:c25:94de:21c2/1282c19:dd:d9:dd:c25:c25:94de:21c2
1962c19:dd:d9:dd:c25:c25:94de:21c3/1282c19:dd:d9:dd:c25:c25:94de:21c3
1972c19:dd:d9:dd:c25:c25:94de:21c4/1282c19:dd:d9:dd:c25:c25:94de:21c4
1982c19:dd:d9:dd:c25:c25:94de:21c5/1282c19:dd:d9:dd:c25:c25:94de:21c5
1992c19:dd:d9:dd:c25:c25:94de:21c6/1282c19:dd:d9:dd:c25:c25:94de:21c6
2002c19:dd:d9:dd:c25:c25:94de:21c7/1282c19:dd:d9:dd:c25:c25:94de:21c7
2012c19:dd:d9:dd:c25:c25:94de:21c8/1282c19:dd:d9:dd:c25:c25:94de:21c8
2022c19:dd:d9:dd:c25:c25:94de:21c9/1282c19:dd:d9:dd:c25:c25:94de:21c9
2032c19:dd:d9:dd:c25:c25:94de:21ca/1282c19:dd:d9:dd:c25:c25:94de:21ca
2042c19:dd:d9:dd:c25:c25:94de:21cb/1282c19:dd:d9:dd:c25:c25:94de:21cb
2052c19:dd:d9:dd:c25:c25:94de:21cc/1282c19:dd:d9:dd:c25:c25:94de:21cc
2062c19:dd:d9:dd:c25:c25:94de:21cd/1282c19:dd:d9:dd:c25:c25:94de:21cd
2072c19:dd:d9:dd:c25:c25:94de:21ce/1282c19:dd:d9:dd:c25:c25:94de:21ce
2082c19:dd:d9:dd:c25:c25:94de:21cf/1282c19:dd:d9:dd:c25:c25:94de:21cf
2092c19:dd:d9:dd:c25:c25:94de:21d0/1282c19:dd:d9:dd:c25:c25:94de:21d0
2102c19:dd:d9:dd:c25:c25:94de:21d1/1282c19:dd:d9:dd:c25:c25:94de:21d1
2112c19:dd:d9:dd:c25:c25:94de:21d2/1282c19:dd:d9:dd:c25:c25:94de:21d2
2122c19:dd:d9:dd:c25:c25:94de:21d3/1282c19:dd:d9:dd:c25:c25:94de:21d3
2132c19:dd:d9:dd:c25:c25:94de:21d4/1282c19:dd:d9:dd:c25:c25:94de:21d4
2142c19:dd:d9:dd:c25:c25:94de:21d5/1282c19:dd:d9:dd:c25:c25:94de:21d5
2152c19:dd:d9:dd:c25:c25:94de:21d6/1282c19:dd:d9:dd:c25:c25:94de:21d6
2162c19:dd:d9:dd:c25:c25:94de:21d7/1282c19:dd:d9:dd:c25:c25:94de:21d7
2172c19:dd:d9:dd:c25:c25:94de:21d8/1282c19:dd:d9:dd:c25:c25:94de:21d8
2182c19:dd:d9:dd:c25:c25:94de:21d9/1282c19:dd:d9:dd:c25:c25:94de:21d9
2192c19:dd:d9:dd:c25:c25:94de:21da/1282c19:dd:d9:dd:c25:c25:94de:21da
2202c19:dd:d9:dd:c25:c25:94de:21db/1282c19:dd:d9:dd:c25:c25:94de:21db
2212c19:dd:d9:dd:c25:c25:94de:21dc/1282c19:dd:d9:dd:c25:c25:94de:21dc
2222c19:dd:d9:dd:c25:c25:94de:21dd/1282c19:dd:d9:dd:c25:c25:94de:21dd
2232c19:dd:d9:dd:c25:c25:94de:21de/1282c19:dd:d9:dd:c25:c25:94de:21de
2242c19:dd:d9:dd:c25:c25:94de:21df/1282c19:dd:d9:dd:c25:c25:94de:21df
2252c19:dd:d9:dd:c25:c25:94de:21e0/1282c19:dd:d9:dd:c25:c25:94de:21e0
2262c19:dd:d9:dd:c25:c25:94de:21e1/1282c19:dd:d9:dd:c25:c25:94de:21e1
2272c19:dd:d9:dd:c25:c25:94de:21e2/1282c19:dd:d9:dd:c25:c25:94de:21e2
2282c19:dd:d9:dd:c25:c25:94de:21e3/1282c19:dd:d9:dd:c25:c25:94de:21e3
2292c19:dd:d9:dd:c25:c25:94de:21e4/1282c19:dd:d9:dd:c25:c25:94de:21e4
2302c19:dd:d9:dd:c25:c25:94de:21e5/1282c19:dd:d9:dd:c25:c25:94de:21e5
2312c19:dd:d9:dd:c25:c25:94de:21e6/1282c19:dd:d9:dd:c25:c25:94de:21e6
2322c19:dd:d9:dd:c25:c25:94de:21e7/1282c19:dd:d9:dd:c25:c25:94de:21e7
2332c19:dd:d9:dd:c25:c25:94de:21e8/1282c19:dd:d9:dd:c25:c25:94de:21e8
2342c19:dd:d9:dd:c25:c25:94de:21e9/1282c19:dd:d9:dd:c25:c25:94de:21e9
2352c19:dd:d9:dd:c25:c25:94de:21ea/1282c19:dd:d9:dd:c25:c25:94de:21ea
2362c19:dd:d9:dd:c25:c25:94de:21eb/1282c19:dd:d9:dd:c25:c25:94de:21eb
2372c19:dd:d9:dd:c25:c25:94de:21ec/1282c19:dd:d9:dd:c25:c25:94de:21ec
2382c19:dd:d9:dd:c25:c25:94de:21ed/1282c19:dd:d9:dd:c25:c25:94de:21ed
2392c19:dd:d9:dd:c25:c25:94de:21ee/1282c19:dd:d9:dd:c25:c25:94de:21ee
2402c19:dd:d9:dd:c25:c25:94de:21ef/1282c19:dd:d9:dd:c25:c25:94de:21ef
2412c19:dd:d9:dd:c25:c25:94de:21f0/1282c19:dd:d9:dd:c25:c25:94de:21f0
2422c19:dd:d9:dd:c25:c25:94de:21f1/1282c19:dd:d9:dd:c25:c25:94de:21f1
2432c19:dd:d9:dd:c25:c25:94de:21f2/1282c19:dd:d9:dd:c25:c25:94de:21f2
2442c19:dd:d9:dd:c25:c25:94de:21f3/1282c19:dd:d9:dd:c25:c25:94de:21f3
2452c19:dd:d9:dd:c25:c25:94de:21f4/1282c19:dd:d9:dd:c25:c25:94de:21f4
2462c19:dd:d9:dd:c25:c25:94de:21f5/1282c19:dd:d9:dd:c25:c25:94de:21f5
2472c19:dd:d9:dd:c25:c25:94de:21f6/1282c19:dd:d9:dd:c25:c25:94de:21f6
2482c19:dd:d9:dd:c25:c25:94de:21f7/1282c19:dd:d9:dd:c25:c25:94de:21f7
2492c19:dd:d9:dd:c25:c25:94de:21f8/1282c19:dd:d9:dd:c25:c25:94de:21f8
2502c19:dd:d9:dd:c25:c25:94de:21f9/1282c19:dd:d9:dd:c25:c25:94de:21f9
2512c19:dd:d9:dd:c25:c25:94de:21fa/1282c19:dd:d9:dd:c25:c25:94de:21fa
2522c19:dd:d9:dd:c25:c25:94de:21fb/1282c19:dd:d9:dd:c25:c25:94de:21fb
2532c19:dd:d9:dd:c25:c25:94de:21fc/1282c19:dd:d9:dd:c25:c25:94de:21fc
2542c19:dd:d9:dd:c25:c25:94de:21fd/1282c19:dd:d9:dd:c25:c25:94de:21fd
2552c19:dd:d9:dd:c25:c25:94de:21fe/1282c19:dd:d9:dd:c25:c25:94de:21fe
2562c19:dd:d9:dd:c25:c25:94de:21ff/1282c19:dd:d9:dd:c25:c25:94de:21ff

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.