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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/116
Addresses4,096
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:c004:9000/116
First address
2c19:dd:d9:dd:c25:c25:c004:9000
Last address
2c19:dd:d9:dd:c25:c25:c004:9fff
Addresses
4,096
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:c004:9000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.4.0.0.c.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/127
/117 (2)/118 (4)/119 (8)/120 (16)/124 (256)/127 (2,048)/128 (4,096)

2c19:dd:d9:dd:c25:c25:c004:9000/116 makes 2,048 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:c004:9000/1272c19:dd:d9:dd:c25:c25:c004:9001
22c19:dd:d9:dd:c25:c25:c004:9002/1272c19:dd:d9:dd:c25:c25:c004:9003
32c19:dd:d9:dd:c25:c25:c004:9004/1272c19:dd:d9:dd:c25:c25:c004:9005
42c19:dd:d9:dd:c25:c25:c004:9006/1272c19:dd:d9:dd:c25:c25:c004:9007
52c19:dd:d9:dd:c25:c25:c004:9008/1272c19:dd:d9:dd:c25:c25:c004:9009
62c19:dd:d9:dd:c25:c25:c004:900a/1272c19:dd:d9:dd:c25:c25:c004:900b
72c19:dd:d9:dd:c25:c25:c004:900c/1272c19:dd:d9:dd:c25:c25:c004:900d
82c19:dd:d9:dd:c25:c25:c004:900e/1272c19:dd:d9:dd:c25:c25:c004:900f
92c19:dd:d9:dd:c25:c25:c004:9010/1272c19:dd:d9:dd:c25:c25:c004:9011
102c19:dd:d9:dd:c25:c25:c004:9012/1272c19:dd:d9:dd:c25:c25:c004:9013
112c19:dd:d9:dd:c25:c25:c004:9014/1272c19:dd:d9:dd:c25:c25:c004:9015
122c19:dd:d9:dd:c25:c25:c004:9016/1272c19:dd:d9:dd:c25:c25:c004:9017
132c19:dd:d9:dd:c25:c25:c004:9018/1272c19:dd:d9:dd:c25:c25:c004:9019
142c19:dd:d9:dd:c25:c25:c004:901a/1272c19:dd:d9:dd:c25:c25:c004:901b
152c19:dd:d9:dd:c25:c25:c004:901c/1272c19:dd:d9:dd:c25:c25:c004:901d
162c19:dd:d9:dd:c25:c25:c004:901e/1272c19:dd:d9:dd:c25:c25:c004:901f
172c19:dd:d9:dd:c25:c25:c004:9020/1272c19:dd:d9:dd:c25:c25:c004:9021
182c19:dd:d9:dd:c25:c25:c004:9022/1272c19:dd:d9:dd:c25:c25:c004:9023
192c19:dd:d9:dd:c25:c25:c004:9024/1272c19:dd:d9:dd:c25:c25:c004:9025
202c19:dd:d9:dd:c25:c25:c004:9026/1272c19:dd:d9:dd:c25:c25:c004:9027
212c19:dd:d9:dd:c25:c25:c004:9028/1272c19:dd:d9:dd:c25:c25:c004:9029
222c19:dd:d9:dd:c25:c25:c004:902a/1272c19:dd:d9:dd:c25:c25:c004:902b
232c19:dd:d9:dd:c25:c25:c004:902c/1272c19:dd:d9:dd:c25:c25:c004:902d
242c19:dd:d9:dd:c25:c25:c004:902e/1272c19:dd:d9:dd:c25:c25:c004:902f
252c19:dd:d9:dd:c25:c25:c004:9030/1272c19:dd:d9:dd:c25:c25:c004:9031
262c19:dd:d9:dd:c25:c25:c004:9032/1272c19:dd:d9:dd:c25:c25:c004:9033
272c19:dd:d9:dd:c25:c25:c004:9034/1272c19:dd:d9:dd:c25:c25:c004:9035
282c19:dd:d9:dd:c25:c25:c004:9036/1272c19:dd:d9:dd:c25:c25:c004:9037
292c19:dd:d9:dd:c25:c25:c004:9038/1272c19:dd:d9:dd:c25:c25:c004:9039
302c19:dd:d9:dd:c25:c25:c004:903a/1272c19:dd:d9:dd:c25:c25:c004:903b
312c19:dd:d9:dd:c25:c25:c004:903c/1272c19:dd:d9:dd:c25:c25:c004:903d
322c19:dd:d9:dd:c25:c25:c004:903e/1272c19:dd:d9:dd:c25:c25:c004:903f
332c19:dd:d9:dd:c25:c25:c004:9040/1272c19:dd:d9:dd:c25:c25:c004:9041
342c19:dd:d9:dd:c25:c25:c004:9042/1272c19:dd:d9:dd:c25:c25:c004:9043
352c19:dd:d9:dd:c25:c25:c004:9044/1272c19:dd:d9:dd:c25:c25:c004:9045
362c19:dd:d9:dd:c25:c25:c004:9046/1272c19:dd:d9:dd:c25:c25:c004:9047
372c19:dd:d9:dd:c25:c25:c004:9048/1272c19:dd:d9:dd:c25:c25:c004:9049
382c19:dd:d9:dd:c25:c25:c004:904a/1272c19:dd:d9:dd:c25:c25:c004:904b
392c19:dd:d9:dd:c25:c25:c004:904c/1272c19:dd:d9:dd:c25:c25:c004:904d
402c19:dd:d9:dd:c25:c25:c004:904e/1272c19:dd:d9:dd:c25:c25:c004:904f
412c19:dd:d9:dd:c25:c25:c004:9050/1272c19:dd:d9:dd:c25:c25:c004:9051
422c19:dd:d9:dd:c25:c25:c004:9052/1272c19:dd:d9:dd:c25:c25:c004:9053
432c19:dd:d9:dd:c25:c25:c004:9054/1272c19:dd:d9:dd:c25:c25:c004:9055
442c19:dd:d9:dd:c25:c25:c004:9056/1272c19:dd:d9:dd:c25:c25:c004:9057
452c19:dd:d9:dd:c25:c25:c004:9058/1272c19:dd:d9:dd:c25:c25:c004:9059
462c19:dd:d9:dd:c25:c25:c004:905a/1272c19:dd:d9:dd:c25:c25:c004:905b
472c19:dd:d9:dd:c25:c25:c004:905c/1272c19:dd:d9:dd:c25:c25:c004:905d
482c19:dd:d9:dd:c25:c25:c004:905e/1272c19:dd:d9:dd:c25:c25:c004:905f
492c19:dd:d9:dd:c25:c25:c004:9060/1272c19:dd:d9:dd:c25:c25:c004:9061
502c19:dd:d9:dd:c25:c25:c004:9062/1272c19:dd:d9:dd:c25:c25:c004:9063
512c19:dd:d9:dd:c25:c25:c004:9064/1272c19:dd:d9:dd:c25:c25:c004:9065
522c19:dd:d9:dd:c25:c25:c004:9066/1272c19:dd:d9:dd:c25:c25:c004:9067
532c19:dd:d9:dd:c25:c25:c004:9068/1272c19:dd:d9:dd:c25:c25:c004:9069
542c19:dd:d9:dd:c25:c25:c004:906a/1272c19:dd:d9:dd:c25:c25:c004:906b
552c19:dd:d9:dd:c25:c25:c004:906c/1272c19:dd:d9:dd:c25:c25:c004:906d
562c19:dd:d9:dd:c25:c25:c004:906e/1272c19:dd:d9:dd:c25:c25:c004:906f
572c19:dd:d9:dd:c25:c25:c004:9070/1272c19:dd:d9:dd:c25:c25:c004:9071
582c19:dd:d9:dd:c25:c25:c004:9072/1272c19:dd:d9:dd:c25:c25:c004:9073
592c19:dd:d9:dd:c25:c25:c004:9074/1272c19:dd:d9:dd:c25:c25:c004:9075
602c19:dd:d9:dd:c25:c25:c004:9076/1272c19:dd:d9:dd:c25:c25:c004:9077
612c19:dd:d9:dd:c25:c25:c004:9078/1272c19:dd:d9:dd:c25:c25:c004:9079
622c19:dd:d9:dd:c25:c25:c004:907a/1272c19:dd:d9:dd:c25:c25:c004:907b
632c19:dd:d9:dd:c25:c25:c004:907c/1272c19:dd:d9:dd:c25:c25:c004:907d
642c19:dd:d9:dd:c25:c25:c004:907e/1272c19:dd:d9:dd:c25:c25:c004:907f
652c19:dd:d9:dd:c25:c25:c004:9080/1272c19:dd:d9:dd:c25:c25:c004:9081
662c19:dd:d9:dd:c25:c25:c004:9082/1272c19:dd:d9:dd:c25:c25:c004:9083
672c19:dd:d9:dd:c25:c25:c004:9084/1272c19:dd:d9:dd:c25:c25:c004:9085
682c19:dd:d9:dd:c25:c25:c004:9086/1272c19:dd:d9:dd:c25:c25:c004:9087
692c19:dd:d9:dd:c25:c25:c004:9088/1272c19:dd:d9:dd:c25:c25:c004:9089
702c19:dd:d9:dd:c25:c25:c004:908a/1272c19:dd:d9:dd:c25:c25:c004:908b
712c19:dd:d9:dd:c25:c25:c004:908c/1272c19:dd:d9:dd:c25:c25:c004:908d
722c19:dd:d9:dd:c25:c25:c004:908e/1272c19:dd:d9:dd:c25:c25:c004:908f
732c19:dd:d9:dd:c25:c25:c004:9090/1272c19:dd:d9:dd:c25:c25:c004:9091
742c19:dd:d9:dd:c25:c25:c004:9092/1272c19:dd:d9:dd:c25:c25:c004:9093
752c19:dd:d9:dd:c25:c25:c004:9094/1272c19:dd:d9:dd:c25:c25:c004:9095
762c19:dd:d9:dd:c25:c25:c004:9096/1272c19:dd:d9:dd:c25:c25:c004:9097
772c19:dd:d9:dd:c25:c25:c004:9098/1272c19:dd:d9:dd:c25:c25:c004:9099
782c19:dd:d9:dd:c25:c25:c004:909a/1272c19:dd:d9:dd:c25:c25:c004:909b
792c19:dd:d9:dd:c25:c25:c004:909c/1272c19:dd:d9:dd:c25:c25:c004:909d
802c19:dd:d9:dd:c25:c25:c004:909e/1272c19:dd:d9:dd:c25:c25:c004:909f
812c19:dd:d9:dd:c25:c25:c004:90a0/1272c19:dd:d9:dd:c25:c25:c004:90a1
822c19:dd:d9:dd:c25:c25:c004:90a2/1272c19:dd:d9:dd:c25:c25:c004:90a3
832c19:dd:d9:dd:c25:c25:c004:90a4/1272c19:dd:d9:dd:c25:c25:c004:90a5
842c19:dd:d9:dd:c25:c25:c004:90a6/1272c19:dd:d9:dd:c25:c25:c004:90a7
852c19:dd:d9:dd:c25:c25:c004:90a8/1272c19:dd:d9:dd:c25:c25:c004:90a9
862c19:dd:d9:dd:c25:c25:c004:90aa/1272c19:dd:d9:dd:c25:c25:c004:90ab
872c19:dd:d9:dd:c25:c25:c004:90ac/1272c19:dd:d9:dd:c25:c25:c004:90ad
882c19:dd:d9:dd:c25:c25:c004:90ae/1272c19:dd:d9:dd:c25:c25:c004:90af
892c19:dd:d9:dd:c25:c25:c004:90b0/1272c19:dd:d9:dd:c25:c25:c004:90b1
902c19:dd:d9:dd:c25:c25:c004:90b2/1272c19:dd:d9:dd:c25:c25:c004:90b3
912c19:dd:d9:dd:c25:c25:c004:90b4/1272c19:dd:d9:dd:c25:c25:c004:90b5
922c19:dd:d9:dd:c25:c25:c004:90b6/1272c19:dd:d9:dd:c25:c25:c004:90b7
932c19:dd:d9:dd:c25:c25:c004:90b8/1272c19:dd:d9:dd:c25:c25:c004:90b9
942c19:dd:d9:dd:c25:c25:c004:90ba/1272c19:dd:d9:dd:c25:c25:c004:90bb
952c19:dd:d9:dd:c25:c25:c004:90bc/1272c19:dd:d9:dd:c25:c25:c004:90bd
962c19:dd:d9:dd:c25:c25:c004:90be/1272c19:dd:d9:dd:c25:c25:c004:90bf
972c19:dd:d9:dd:c25:c25:c004:90c0/1272c19:dd:d9:dd:c25:c25:c004:90c1
982c19:dd:d9:dd:c25:c25:c004:90c2/1272c19:dd:d9:dd:c25:c25:c004:90c3
992c19:dd:d9:dd:c25:c25:c004:90c4/1272c19:dd:d9:dd:c25:c25:c004:90c5
1002c19:dd:d9:dd:c25:c25:c004:90c6/1272c19:dd:d9:dd:c25:c25:c004:90c7
1012c19:dd:d9:dd:c25:c25:c004:90c8/1272c19:dd:d9:dd:c25:c25:c004:90c9
1022c19:dd:d9:dd:c25:c25:c004:90ca/1272c19:dd:d9:dd:c25:c25:c004:90cb
1032c19:dd:d9:dd:c25:c25:c004:90cc/1272c19:dd:d9:dd:c25:c25:c004:90cd
1042c19:dd:d9:dd:c25:c25:c004:90ce/1272c19:dd:d9:dd:c25:c25:c004:90cf
1052c19:dd:d9:dd:c25:c25:c004:90d0/1272c19:dd:d9:dd:c25:c25:c004:90d1
1062c19:dd:d9:dd:c25:c25:c004:90d2/1272c19:dd:d9:dd:c25:c25:c004:90d3
1072c19:dd:d9:dd:c25:c25:c004:90d4/1272c19:dd:d9:dd:c25:c25:c004:90d5
1082c19:dd:d9:dd:c25:c25:c004:90d6/1272c19:dd:d9:dd:c25:c25:c004:90d7
1092c19:dd:d9:dd:c25:c25:c004:90d8/1272c19:dd:d9:dd:c25:c25:c004:90d9
1102c19:dd:d9:dd:c25:c25:c004:90da/1272c19:dd:d9:dd:c25:c25:c004:90db
1112c19:dd:d9:dd:c25:c25:c004:90dc/1272c19:dd:d9:dd:c25:c25:c004:90dd
1122c19:dd:d9:dd:c25:c25:c004:90de/1272c19:dd:d9:dd:c25:c25:c004:90df
1132c19:dd:d9:dd:c25:c25:c004:90e0/1272c19:dd:d9:dd:c25:c25:c004:90e1
1142c19:dd:d9:dd:c25:c25:c004:90e2/1272c19:dd:d9:dd:c25:c25:c004:90e3
1152c19:dd:d9:dd:c25:c25:c004:90e4/1272c19:dd:d9:dd:c25:c25:c004:90e5
1162c19:dd:d9:dd:c25:c25:c004:90e6/1272c19:dd:d9:dd:c25:c25:c004:90e7
1172c19:dd:d9:dd:c25:c25:c004:90e8/1272c19:dd:d9:dd:c25:c25:c004:90e9
1182c19:dd:d9:dd:c25:c25:c004:90ea/1272c19:dd:d9:dd:c25:c25:c004:90eb
1192c19:dd:d9:dd:c25:c25:c004:90ec/1272c19:dd:d9:dd:c25:c25:c004:90ed
1202c19:dd:d9:dd:c25:c25:c004:90ee/1272c19:dd:d9:dd:c25:c25:c004:90ef
1212c19:dd:d9:dd:c25:c25:c004:90f0/1272c19:dd:d9:dd:c25:c25:c004:90f1
1222c19:dd:d9:dd:c25:c25:c004:90f2/1272c19:dd:d9:dd:c25:c25:c004:90f3
1232c19:dd:d9:dd:c25:c25:c004:90f4/1272c19:dd:d9:dd:c25:c25:c004:90f5
1242c19:dd:d9:dd:c25:c25:c004:90f6/1272c19:dd:d9:dd:c25:c25:c004:90f7
1252c19:dd:d9:dd:c25:c25:c004:90f8/1272c19:dd:d9:dd:c25:c25:c004:90f9
1262c19:dd:d9:dd:c25:c25:c004:90fa/1272c19:dd:d9:dd:c25:c25:c004:90fb
1272c19:dd:d9:dd:c25:c25:c004:90fc/1272c19:dd:d9:dd:c25:c25:c004:90fd
1282c19:dd:d9:dd:c25:c25:c004:90fe/1272c19:dd:d9:dd:c25:c25:c004:90ff
1292c19:dd:d9:dd:c25:c25:c004:9100/1272c19:dd:d9:dd:c25:c25:c004:9101
1302c19:dd:d9:dd:c25:c25:c004:9102/1272c19:dd:d9:dd:c25:c25:c004:9103
1312c19:dd:d9:dd:c25:c25:c004:9104/1272c19:dd:d9:dd:c25:c25:c004:9105
1322c19:dd:d9:dd:c25:c25:c004:9106/1272c19:dd:d9:dd:c25:c25:c004:9107
1332c19:dd:d9:dd:c25:c25:c004:9108/1272c19:dd:d9:dd:c25:c25:c004:9109
1342c19:dd:d9:dd:c25:c25:c004:910a/1272c19:dd:d9:dd:c25:c25:c004:910b
1352c19:dd:d9:dd:c25:c25:c004:910c/1272c19:dd:d9:dd:c25:c25:c004:910d
1362c19:dd:d9:dd:c25:c25:c004:910e/1272c19:dd:d9:dd:c25:c25:c004:910f
1372c19:dd:d9:dd:c25:c25:c004:9110/1272c19:dd:d9:dd:c25:c25:c004:9111
1382c19:dd:d9:dd:c25:c25:c004:9112/1272c19:dd:d9:dd:c25:c25:c004:9113
1392c19:dd:d9:dd:c25:c25:c004:9114/1272c19:dd:d9:dd:c25:c25:c004:9115
1402c19:dd:d9:dd:c25:c25:c004:9116/1272c19:dd:d9:dd:c25:c25:c004:9117
1412c19:dd:d9:dd:c25:c25:c004:9118/1272c19:dd:d9:dd:c25:c25:c004:9119
1422c19:dd:d9:dd:c25:c25:c004:911a/1272c19:dd:d9:dd:c25:c25:c004:911b
1432c19:dd:d9:dd:c25:c25:c004:911c/1272c19:dd:d9:dd:c25:c25:c004:911d
1442c19:dd:d9:dd:c25:c25:c004:911e/1272c19:dd:d9:dd:c25:c25:c004:911f
1452c19:dd:d9:dd:c25:c25:c004:9120/1272c19:dd:d9:dd:c25:c25:c004:9121
1462c19:dd:d9:dd:c25:c25:c004:9122/1272c19:dd:d9:dd:c25:c25:c004:9123
1472c19:dd:d9:dd:c25:c25:c004:9124/1272c19:dd:d9:dd:c25:c25:c004:9125
1482c19:dd:d9:dd:c25:c25:c004:9126/1272c19:dd:d9:dd:c25:c25:c004:9127
1492c19:dd:d9:dd:c25:c25:c004:9128/1272c19:dd:d9:dd:c25:c25:c004:9129
1502c19:dd:d9:dd:c25:c25:c004:912a/1272c19:dd:d9:dd:c25:c25:c004:912b
1512c19:dd:d9:dd:c25:c25:c004:912c/1272c19:dd:d9:dd:c25:c25:c004:912d
1522c19:dd:d9:dd:c25:c25:c004:912e/1272c19:dd:d9:dd:c25:c25:c004:912f
1532c19:dd:d9:dd:c25:c25:c004:9130/1272c19:dd:d9:dd:c25:c25:c004:9131
1542c19:dd:d9:dd:c25:c25:c004:9132/1272c19:dd:d9:dd:c25:c25:c004:9133
1552c19:dd:d9:dd:c25:c25:c004:9134/1272c19:dd:d9:dd:c25:c25:c004:9135
1562c19:dd:d9:dd:c25:c25:c004:9136/1272c19:dd:d9:dd:c25:c25:c004:9137
1572c19:dd:d9:dd:c25:c25:c004:9138/1272c19:dd:d9:dd:c25:c25:c004:9139
1582c19:dd:d9:dd:c25:c25:c004:913a/1272c19:dd:d9:dd:c25:c25:c004:913b
1592c19:dd:d9:dd:c25:c25:c004:913c/1272c19:dd:d9:dd:c25:c25:c004:913d
1602c19:dd:d9:dd:c25:c25:c004:913e/1272c19:dd:d9:dd:c25:c25:c004:913f
1612c19:dd:d9:dd:c25:c25:c004:9140/1272c19:dd:d9:dd:c25:c25:c004:9141
1622c19:dd:d9:dd:c25:c25:c004:9142/1272c19:dd:d9:dd:c25:c25:c004:9143
1632c19:dd:d9:dd:c25:c25:c004:9144/1272c19:dd:d9:dd:c25:c25:c004:9145
1642c19:dd:d9:dd:c25:c25:c004:9146/1272c19:dd:d9:dd:c25:c25:c004:9147
1652c19:dd:d9:dd:c25:c25:c004:9148/1272c19:dd:d9:dd:c25:c25:c004:9149
1662c19:dd:d9:dd:c25:c25:c004:914a/1272c19:dd:d9:dd:c25:c25:c004:914b
1672c19:dd:d9:dd:c25:c25:c004:914c/1272c19:dd:d9:dd:c25:c25:c004:914d
1682c19:dd:d9:dd:c25:c25:c004:914e/1272c19:dd:d9:dd:c25:c25:c004:914f
1692c19:dd:d9:dd:c25:c25:c004:9150/1272c19:dd:d9:dd:c25:c25:c004:9151
1702c19:dd:d9:dd:c25:c25:c004:9152/1272c19:dd:d9:dd:c25:c25:c004:9153
1712c19:dd:d9:dd:c25:c25:c004:9154/1272c19:dd:d9:dd:c25:c25:c004:9155
1722c19:dd:d9:dd:c25:c25:c004:9156/1272c19:dd:d9:dd:c25:c25:c004:9157
1732c19:dd:d9:dd:c25:c25:c004:9158/1272c19:dd:d9:dd:c25:c25:c004:9159
1742c19:dd:d9:dd:c25:c25:c004:915a/1272c19:dd:d9:dd:c25:c25:c004:915b
1752c19:dd:d9:dd:c25:c25:c004:915c/1272c19:dd:d9:dd:c25:c25:c004:915d
1762c19:dd:d9:dd:c25:c25:c004:915e/1272c19:dd:d9:dd:c25:c25:c004:915f
1772c19:dd:d9:dd:c25:c25:c004:9160/1272c19:dd:d9:dd:c25:c25:c004:9161
1782c19:dd:d9:dd:c25:c25:c004:9162/1272c19:dd:d9:dd:c25:c25:c004:9163
1792c19:dd:d9:dd:c25:c25:c004:9164/1272c19:dd:d9:dd:c25:c25:c004:9165
1802c19:dd:d9:dd:c25:c25:c004:9166/1272c19:dd:d9:dd:c25:c25:c004:9167
1812c19:dd:d9:dd:c25:c25:c004:9168/1272c19:dd:d9:dd:c25:c25:c004:9169
1822c19:dd:d9:dd:c25:c25:c004:916a/1272c19:dd:d9:dd:c25:c25:c004:916b
1832c19:dd:d9:dd:c25:c25:c004:916c/1272c19:dd:d9:dd:c25:c25:c004:916d
1842c19:dd:d9:dd:c25:c25:c004:916e/1272c19:dd:d9:dd:c25:c25:c004:916f
1852c19:dd:d9:dd:c25:c25:c004:9170/1272c19:dd:d9:dd:c25:c25:c004:9171
1862c19:dd:d9:dd:c25:c25:c004:9172/1272c19:dd:d9:dd:c25:c25:c004:9173
1872c19:dd:d9:dd:c25:c25:c004:9174/1272c19:dd:d9:dd:c25:c25:c004:9175
1882c19:dd:d9:dd:c25:c25:c004:9176/1272c19:dd:d9:dd:c25:c25:c004:9177
1892c19:dd:d9:dd:c25:c25:c004:9178/1272c19:dd:d9:dd:c25:c25:c004:9179
1902c19:dd:d9:dd:c25:c25:c004:917a/1272c19:dd:d9:dd:c25:c25:c004:917b
1912c19:dd:d9:dd:c25:c25:c004:917c/1272c19:dd:d9:dd:c25:c25:c004:917d
1922c19:dd:d9:dd:c25:c25:c004:917e/1272c19:dd:d9:dd:c25:c25:c004:917f
1932c19:dd:d9:dd:c25:c25:c004:9180/1272c19:dd:d9:dd:c25:c25:c004:9181
1942c19:dd:d9:dd:c25:c25:c004:9182/1272c19:dd:d9:dd:c25:c25:c004:9183
1952c19:dd:d9:dd:c25:c25:c004:9184/1272c19:dd:d9:dd:c25:c25:c004:9185
1962c19:dd:d9:dd:c25:c25:c004:9186/1272c19:dd:d9:dd:c25:c25:c004:9187
1972c19:dd:d9:dd:c25:c25:c004:9188/1272c19:dd:d9:dd:c25:c25:c004:9189
1982c19:dd:d9:dd:c25:c25:c004:918a/1272c19:dd:d9:dd:c25:c25:c004:918b
1992c19:dd:d9:dd:c25:c25:c004:918c/1272c19:dd:d9:dd:c25:c25:c004:918d
2002c19:dd:d9:dd:c25:c25:c004:918e/1272c19:dd:d9:dd:c25:c25:c004:918f
2012c19:dd:d9:dd:c25:c25:c004:9190/1272c19:dd:d9:dd:c25:c25:c004:9191
2022c19:dd:d9:dd:c25:c25:c004:9192/1272c19:dd:d9:dd:c25:c25:c004:9193
2032c19:dd:d9:dd:c25:c25:c004:9194/1272c19:dd:d9:dd:c25:c25:c004:9195
2042c19:dd:d9:dd:c25:c25:c004:9196/1272c19:dd:d9:dd:c25:c25:c004:9197
2052c19:dd:d9:dd:c25:c25:c004:9198/1272c19:dd:d9:dd:c25:c25:c004:9199
2062c19:dd:d9:dd:c25:c25:c004:919a/1272c19:dd:d9:dd:c25:c25:c004:919b
2072c19:dd:d9:dd:c25:c25:c004:919c/1272c19:dd:d9:dd:c25:c25:c004:919d
2082c19:dd:d9:dd:c25:c25:c004:919e/1272c19:dd:d9:dd:c25:c25:c004:919f
2092c19:dd:d9:dd:c25:c25:c004:91a0/1272c19:dd:d9:dd:c25:c25:c004:91a1
2102c19:dd:d9:dd:c25:c25:c004:91a2/1272c19:dd:d9:dd:c25:c25:c004:91a3
2112c19:dd:d9:dd:c25:c25:c004:91a4/1272c19:dd:d9:dd:c25:c25:c004:91a5
2122c19:dd:d9:dd:c25:c25:c004:91a6/1272c19:dd:d9:dd:c25:c25:c004:91a7
2132c19:dd:d9:dd:c25:c25:c004:91a8/1272c19:dd:d9:dd:c25:c25:c004:91a9
2142c19:dd:d9:dd:c25:c25:c004:91aa/1272c19:dd:d9:dd:c25:c25:c004:91ab
2152c19:dd:d9:dd:c25:c25:c004:91ac/1272c19:dd:d9:dd:c25:c25:c004:91ad
2162c19:dd:d9:dd:c25:c25:c004:91ae/1272c19:dd:d9:dd:c25:c25:c004:91af
2172c19:dd:d9:dd:c25:c25:c004:91b0/1272c19:dd:d9:dd:c25:c25:c004:91b1
2182c19:dd:d9:dd:c25:c25:c004:91b2/1272c19:dd:d9:dd:c25:c25:c004:91b3
2192c19:dd:d9:dd:c25:c25:c004:91b4/1272c19:dd:d9:dd:c25:c25:c004:91b5
2202c19:dd:d9:dd:c25:c25:c004:91b6/1272c19:dd:d9:dd:c25:c25:c004:91b7
2212c19:dd:d9:dd:c25:c25:c004:91b8/1272c19:dd:d9:dd:c25:c25:c004:91b9
2222c19:dd:d9:dd:c25:c25:c004:91ba/1272c19:dd:d9:dd:c25:c25:c004:91bb
2232c19:dd:d9:dd:c25:c25:c004:91bc/1272c19:dd:d9:dd:c25:c25:c004:91bd
2242c19:dd:d9:dd:c25:c25:c004:91be/1272c19:dd:d9:dd:c25:c25:c004:91bf
2252c19:dd:d9:dd:c25:c25:c004:91c0/1272c19:dd:d9:dd:c25:c25:c004:91c1
2262c19:dd:d9:dd:c25:c25:c004:91c2/1272c19:dd:d9:dd:c25:c25:c004:91c3
2272c19:dd:d9:dd:c25:c25:c004:91c4/1272c19:dd:d9:dd:c25:c25:c004:91c5
2282c19:dd:d9:dd:c25:c25:c004:91c6/1272c19:dd:d9:dd:c25:c25:c004:91c7
2292c19:dd:d9:dd:c25:c25:c004:91c8/1272c19:dd:d9:dd:c25:c25:c004:91c9
2302c19:dd:d9:dd:c25:c25:c004:91ca/1272c19:dd:d9:dd:c25:c25:c004:91cb
2312c19:dd:d9:dd:c25:c25:c004:91cc/1272c19:dd:d9:dd:c25:c25:c004:91cd
2322c19:dd:d9:dd:c25:c25:c004:91ce/1272c19:dd:d9:dd:c25:c25:c004:91cf
2332c19:dd:d9:dd:c25:c25:c004:91d0/1272c19:dd:d9:dd:c25:c25:c004:91d1
2342c19:dd:d9:dd:c25:c25:c004:91d2/1272c19:dd:d9:dd:c25:c25:c004:91d3
2352c19:dd:d9:dd:c25:c25:c004:91d4/1272c19:dd:d9:dd:c25:c25:c004:91d5
2362c19:dd:d9:dd:c25:c25:c004:91d6/1272c19:dd:d9:dd:c25:c25:c004:91d7
2372c19:dd:d9:dd:c25:c25:c004:91d8/1272c19:dd:d9:dd:c25:c25:c004:91d9
2382c19:dd:d9:dd:c25:c25:c004:91da/1272c19:dd:d9:dd:c25:c25:c004:91db
2392c19:dd:d9:dd:c25:c25:c004:91dc/1272c19:dd:d9:dd:c25:c25:c004:91dd
2402c19:dd:d9:dd:c25:c25:c004:91de/1272c19:dd:d9:dd:c25:c25:c004:91df
2412c19:dd:d9:dd:c25:c25:c004:91e0/1272c19:dd:d9:dd:c25:c25:c004:91e1
2422c19:dd:d9:dd:c25:c25:c004:91e2/1272c19:dd:d9:dd:c25:c25:c004:91e3
2432c19:dd:d9:dd:c25:c25:c004:91e4/1272c19:dd:d9:dd:c25:c25:c004:91e5
2442c19:dd:d9:dd:c25:c25:c004:91e6/1272c19:dd:d9:dd:c25:c25:c004:91e7
2452c19:dd:d9:dd:c25:c25:c004:91e8/1272c19:dd:d9:dd:c25:c25:c004:91e9
2462c19:dd:d9:dd:c25:c25:c004:91ea/1272c19:dd:d9:dd:c25:c25:c004:91eb
2472c19:dd:d9:dd:c25:c25:c004:91ec/1272c19:dd:d9:dd:c25:c25:c004:91ed
2482c19:dd:d9:dd:c25:c25:c004:91ee/1272c19:dd:d9:dd:c25:c25:c004:91ef
2492c19:dd:d9:dd:c25:c25:c004:91f0/1272c19:dd:d9:dd:c25:c25:c004:91f1
2502c19:dd:d9:dd:c25:c25:c004:91f2/1272c19:dd:d9:dd:c25:c25:c004:91f3
2512c19:dd:d9:dd:c25:c25:c004:91f4/1272c19:dd:d9:dd:c25:c25:c004:91f5
2522c19:dd:d9:dd:c25:c25:c004:91f6/1272c19:dd:d9:dd:c25:c25:c004:91f7
2532c19:dd:d9:dd:c25:c25:c004:91f8/1272c19:dd:d9:dd:c25:c25:c004:91f9
2542c19:dd:d9:dd:c25:c25:c004:91fa/1272c19:dd:d9:dd:c25:c25:c004:91fb
2552c19:dd:d9:dd:c25:c25:c004:91fc/1272c19:dd:d9:dd:c25:c25:c004:91fd
2562c19:dd:d9:dd:c25:c25:c004:91fe/1272c19:dd:d9:dd:c25:c25:c004:91ff

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.