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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:c25:300b:6000/116
First address
2c19:dd:d9:dd:c25:c25:300b:6000
Last address
2c19:dd:d9:dd:c25:c25:300b:6fff
Addresses
4,096
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:300b:6000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.b.0.0.3.5.2.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:c25:300b:6000/116 makes 2,048 subnets of /127; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:300b:6000/1272c19:dd:d9:dd:c25:c25:300b:6001
22c19:dd:d9:dd:c25:c25:300b:6002/1272c19:dd:d9:dd:c25:c25:300b:6003
32c19:dd:d9:dd:c25:c25:300b:6004/1272c19:dd:d9:dd:c25:c25:300b:6005
42c19:dd:d9:dd:c25:c25:300b:6006/1272c19:dd:d9:dd:c25:c25:300b:6007
52c19:dd:d9:dd:c25:c25:300b:6008/1272c19:dd:d9:dd:c25:c25:300b:6009
62c19:dd:d9:dd:c25:c25:300b:600a/1272c19:dd:d9:dd:c25:c25:300b:600b
72c19:dd:d9:dd:c25:c25:300b:600c/1272c19:dd:d9:dd:c25:c25:300b:600d
82c19:dd:d9:dd:c25:c25:300b:600e/1272c19:dd:d9:dd:c25:c25:300b:600f
92c19:dd:d9:dd:c25:c25:300b:6010/1272c19:dd:d9:dd:c25:c25:300b:6011
102c19:dd:d9:dd:c25:c25:300b:6012/1272c19:dd:d9:dd:c25:c25:300b:6013
112c19:dd:d9:dd:c25:c25:300b:6014/1272c19:dd:d9:dd:c25:c25:300b:6015
122c19:dd:d9:dd:c25:c25:300b:6016/1272c19:dd:d9:dd:c25:c25:300b:6017
132c19:dd:d9:dd:c25:c25:300b:6018/1272c19:dd:d9:dd:c25:c25:300b:6019
142c19:dd:d9:dd:c25:c25:300b:601a/1272c19:dd:d9:dd:c25:c25:300b:601b
152c19:dd:d9:dd:c25:c25:300b:601c/1272c19:dd:d9:dd:c25:c25:300b:601d
162c19:dd:d9:dd:c25:c25:300b:601e/1272c19:dd:d9:dd:c25:c25:300b:601f
172c19:dd:d9:dd:c25:c25:300b:6020/1272c19:dd:d9:dd:c25:c25:300b:6021
182c19:dd:d9:dd:c25:c25:300b:6022/1272c19:dd:d9:dd:c25:c25:300b:6023
192c19:dd:d9:dd:c25:c25:300b:6024/1272c19:dd:d9:dd:c25:c25:300b:6025
202c19:dd:d9:dd:c25:c25:300b:6026/1272c19:dd:d9:dd:c25:c25:300b:6027
212c19:dd:d9:dd:c25:c25:300b:6028/1272c19:dd:d9:dd:c25:c25:300b:6029
222c19:dd:d9:dd:c25:c25:300b:602a/1272c19:dd:d9:dd:c25:c25:300b:602b
232c19:dd:d9:dd:c25:c25:300b:602c/1272c19:dd:d9:dd:c25:c25:300b:602d
242c19:dd:d9:dd:c25:c25:300b:602e/1272c19:dd:d9:dd:c25:c25:300b:602f
252c19:dd:d9:dd:c25:c25:300b:6030/1272c19:dd:d9:dd:c25:c25:300b:6031
262c19:dd:d9:dd:c25:c25:300b:6032/1272c19:dd:d9:dd:c25:c25:300b:6033
272c19:dd:d9:dd:c25:c25:300b:6034/1272c19:dd:d9:dd:c25:c25:300b:6035
282c19:dd:d9:dd:c25:c25:300b:6036/1272c19:dd:d9:dd:c25:c25:300b:6037
292c19:dd:d9:dd:c25:c25:300b:6038/1272c19:dd:d9:dd:c25:c25:300b:6039
302c19:dd:d9:dd:c25:c25:300b:603a/1272c19:dd:d9:dd:c25:c25:300b:603b
312c19:dd:d9:dd:c25:c25:300b:603c/1272c19:dd:d9:dd:c25:c25:300b:603d
322c19:dd:d9:dd:c25:c25:300b:603e/1272c19:dd:d9:dd:c25:c25:300b:603f
332c19:dd:d9:dd:c25:c25:300b:6040/1272c19:dd:d9:dd:c25:c25:300b:6041
342c19:dd:d9:dd:c25:c25:300b:6042/1272c19:dd:d9:dd:c25:c25:300b:6043
352c19:dd:d9:dd:c25:c25:300b:6044/1272c19:dd:d9:dd:c25:c25:300b:6045
362c19:dd:d9:dd:c25:c25:300b:6046/1272c19:dd:d9:dd:c25:c25:300b:6047
372c19:dd:d9:dd:c25:c25:300b:6048/1272c19:dd:d9:dd:c25:c25:300b:6049
382c19:dd:d9:dd:c25:c25:300b:604a/1272c19:dd:d9:dd:c25:c25:300b:604b
392c19:dd:d9:dd:c25:c25:300b:604c/1272c19:dd:d9:dd:c25:c25:300b:604d
402c19:dd:d9:dd:c25:c25:300b:604e/1272c19:dd:d9:dd:c25:c25:300b:604f
412c19:dd:d9:dd:c25:c25:300b:6050/1272c19:dd:d9:dd:c25:c25:300b:6051
422c19:dd:d9:dd:c25:c25:300b:6052/1272c19:dd:d9:dd:c25:c25:300b:6053
432c19:dd:d9:dd:c25:c25:300b:6054/1272c19:dd:d9:dd:c25:c25:300b:6055
442c19:dd:d9:dd:c25:c25:300b:6056/1272c19:dd:d9:dd:c25:c25:300b:6057
452c19:dd:d9:dd:c25:c25:300b:6058/1272c19:dd:d9:dd:c25:c25:300b:6059
462c19:dd:d9:dd:c25:c25:300b:605a/1272c19:dd:d9:dd:c25:c25:300b:605b
472c19:dd:d9:dd:c25:c25:300b:605c/1272c19:dd:d9:dd:c25:c25:300b:605d
482c19:dd:d9:dd:c25:c25:300b:605e/1272c19:dd:d9:dd:c25:c25:300b:605f
492c19:dd:d9:dd:c25:c25:300b:6060/1272c19:dd:d9:dd:c25:c25:300b:6061
502c19:dd:d9:dd:c25:c25:300b:6062/1272c19:dd:d9:dd:c25:c25:300b:6063
512c19:dd:d9:dd:c25:c25:300b:6064/1272c19:dd:d9:dd:c25:c25:300b:6065
522c19:dd:d9:dd:c25:c25:300b:6066/1272c19:dd:d9:dd:c25:c25:300b:6067
532c19:dd:d9:dd:c25:c25:300b:6068/1272c19:dd:d9:dd:c25:c25:300b:6069
542c19:dd:d9:dd:c25:c25:300b:606a/1272c19:dd:d9:dd:c25:c25:300b:606b
552c19:dd:d9:dd:c25:c25:300b:606c/1272c19:dd:d9:dd:c25:c25:300b:606d
562c19:dd:d9:dd:c25:c25:300b:606e/1272c19:dd:d9:dd:c25:c25:300b:606f
572c19:dd:d9:dd:c25:c25:300b:6070/1272c19:dd:d9:dd:c25:c25:300b:6071
582c19:dd:d9:dd:c25:c25:300b:6072/1272c19:dd:d9:dd:c25:c25:300b:6073
592c19:dd:d9:dd:c25:c25:300b:6074/1272c19:dd:d9:dd:c25:c25:300b:6075
602c19:dd:d9:dd:c25:c25:300b:6076/1272c19:dd:d9:dd:c25:c25:300b:6077
612c19:dd:d9:dd:c25:c25:300b:6078/1272c19:dd:d9:dd:c25:c25:300b:6079
622c19:dd:d9:dd:c25:c25:300b:607a/1272c19:dd:d9:dd:c25:c25:300b:607b
632c19:dd:d9:dd:c25:c25:300b:607c/1272c19:dd:d9:dd:c25:c25:300b:607d
642c19:dd:d9:dd:c25:c25:300b:607e/1272c19:dd:d9:dd:c25:c25:300b:607f
652c19:dd:d9:dd:c25:c25:300b:6080/1272c19:dd:d9:dd:c25:c25:300b:6081
662c19:dd:d9:dd:c25:c25:300b:6082/1272c19:dd:d9:dd:c25:c25:300b:6083
672c19:dd:d9:dd:c25:c25:300b:6084/1272c19:dd:d9:dd:c25:c25:300b:6085
682c19:dd:d9:dd:c25:c25:300b:6086/1272c19:dd:d9:dd:c25:c25:300b:6087
692c19:dd:d9:dd:c25:c25:300b:6088/1272c19:dd:d9:dd:c25:c25:300b:6089
702c19:dd:d9:dd:c25:c25:300b:608a/1272c19:dd:d9:dd:c25:c25:300b:608b
712c19:dd:d9:dd:c25:c25:300b:608c/1272c19:dd:d9:dd:c25:c25:300b:608d
722c19:dd:d9:dd:c25:c25:300b:608e/1272c19:dd:d9:dd:c25:c25:300b:608f
732c19:dd:d9:dd:c25:c25:300b:6090/1272c19:dd:d9:dd:c25:c25:300b:6091
742c19:dd:d9:dd:c25:c25:300b:6092/1272c19:dd:d9:dd:c25:c25:300b:6093
752c19:dd:d9:dd:c25:c25:300b:6094/1272c19:dd:d9:dd:c25:c25:300b:6095
762c19:dd:d9:dd:c25:c25:300b:6096/1272c19:dd:d9:dd:c25:c25:300b:6097
772c19:dd:d9:dd:c25:c25:300b:6098/1272c19:dd:d9:dd:c25:c25:300b:6099
782c19:dd:d9:dd:c25:c25:300b:609a/1272c19:dd:d9:dd:c25:c25:300b:609b
792c19:dd:d9:dd:c25:c25:300b:609c/1272c19:dd:d9:dd:c25:c25:300b:609d
802c19:dd:d9:dd:c25:c25:300b:609e/1272c19:dd:d9:dd:c25:c25:300b:609f
812c19:dd:d9:dd:c25:c25:300b:60a0/1272c19:dd:d9:dd:c25:c25:300b:60a1
822c19:dd:d9:dd:c25:c25:300b:60a2/1272c19:dd:d9:dd:c25:c25:300b:60a3
832c19:dd:d9:dd:c25:c25:300b:60a4/1272c19:dd:d9:dd:c25:c25:300b:60a5
842c19:dd:d9:dd:c25:c25:300b:60a6/1272c19:dd:d9:dd:c25:c25:300b:60a7
852c19:dd:d9:dd:c25:c25:300b:60a8/1272c19:dd:d9:dd:c25:c25:300b:60a9
862c19:dd:d9:dd:c25:c25:300b:60aa/1272c19:dd:d9:dd:c25:c25:300b:60ab
872c19:dd:d9:dd:c25:c25:300b:60ac/1272c19:dd:d9:dd:c25:c25:300b:60ad
882c19:dd:d9:dd:c25:c25:300b:60ae/1272c19:dd:d9:dd:c25:c25:300b:60af
892c19:dd:d9:dd:c25:c25:300b:60b0/1272c19:dd:d9:dd:c25:c25:300b:60b1
902c19:dd:d9:dd:c25:c25:300b:60b2/1272c19:dd:d9:dd:c25:c25:300b:60b3
912c19:dd:d9:dd:c25:c25:300b:60b4/1272c19:dd:d9:dd:c25:c25:300b:60b5
922c19:dd:d9:dd:c25:c25:300b:60b6/1272c19:dd:d9:dd:c25:c25:300b:60b7
932c19:dd:d9:dd:c25:c25:300b:60b8/1272c19:dd:d9:dd:c25:c25:300b:60b9
942c19:dd:d9:dd:c25:c25:300b:60ba/1272c19:dd:d9:dd:c25:c25:300b:60bb
952c19:dd:d9:dd:c25:c25:300b:60bc/1272c19:dd:d9:dd:c25:c25:300b:60bd
962c19:dd:d9:dd:c25:c25:300b:60be/1272c19:dd:d9:dd:c25:c25:300b:60bf
972c19:dd:d9:dd:c25:c25:300b:60c0/1272c19:dd:d9:dd:c25:c25:300b:60c1
982c19:dd:d9:dd:c25:c25:300b:60c2/1272c19:dd:d9:dd:c25:c25:300b:60c3
992c19:dd:d9:dd:c25:c25:300b:60c4/1272c19:dd:d9:dd:c25:c25:300b:60c5
1002c19:dd:d9:dd:c25:c25:300b:60c6/1272c19:dd:d9:dd:c25:c25:300b:60c7
1012c19:dd:d9:dd:c25:c25:300b:60c8/1272c19:dd:d9:dd:c25:c25:300b:60c9
1022c19:dd:d9:dd:c25:c25:300b:60ca/1272c19:dd:d9:dd:c25:c25:300b:60cb
1032c19:dd:d9:dd:c25:c25:300b:60cc/1272c19:dd:d9:dd:c25:c25:300b:60cd
1042c19:dd:d9:dd:c25:c25:300b:60ce/1272c19:dd:d9:dd:c25:c25:300b:60cf
1052c19:dd:d9:dd:c25:c25:300b:60d0/1272c19:dd:d9:dd:c25:c25:300b:60d1
1062c19:dd:d9:dd:c25:c25:300b:60d2/1272c19:dd:d9:dd:c25:c25:300b:60d3
1072c19:dd:d9:dd:c25:c25:300b:60d4/1272c19:dd:d9:dd:c25:c25:300b:60d5
1082c19:dd:d9:dd:c25:c25:300b:60d6/1272c19:dd:d9:dd:c25:c25:300b:60d7
1092c19:dd:d9:dd:c25:c25:300b:60d8/1272c19:dd:d9:dd:c25:c25:300b:60d9
1102c19:dd:d9:dd:c25:c25:300b:60da/1272c19:dd:d9:dd:c25:c25:300b:60db
1112c19:dd:d9:dd:c25:c25:300b:60dc/1272c19:dd:d9:dd:c25:c25:300b:60dd
1122c19:dd:d9:dd:c25:c25:300b:60de/1272c19:dd:d9:dd:c25:c25:300b:60df
1132c19:dd:d9:dd:c25:c25:300b:60e0/1272c19:dd:d9:dd:c25:c25:300b:60e1
1142c19:dd:d9:dd:c25:c25:300b:60e2/1272c19:dd:d9:dd:c25:c25:300b:60e3
1152c19:dd:d9:dd:c25:c25:300b:60e4/1272c19:dd:d9:dd:c25:c25:300b:60e5
1162c19:dd:d9:dd:c25:c25:300b:60e6/1272c19:dd:d9:dd:c25:c25:300b:60e7
1172c19:dd:d9:dd:c25:c25:300b:60e8/1272c19:dd:d9:dd:c25:c25:300b:60e9
1182c19:dd:d9:dd:c25:c25:300b:60ea/1272c19:dd:d9:dd:c25:c25:300b:60eb
1192c19:dd:d9:dd:c25:c25:300b:60ec/1272c19:dd:d9:dd:c25:c25:300b:60ed
1202c19:dd:d9:dd:c25:c25:300b:60ee/1272c19:dd:d9:dd:c25:c25:300b:60ef
1212c19:dd:d9:dd:c25:c25:300b:60f0/1272c19:dd:d9:dd:c25:c25:300b:60f1
1222c19:dd:d9:dd:c25:c25:300b:60f2/1272c19:dd:d9:dd:c25:c25:300b:60f3
1232c19:dd:d9:dd:c25:c25:300b:60f4/1272c19:dd:d9:dd:c25:c25:300b:60f5
1242c19:dd:d9:dd:c25:c25:300b:60f6/1272c19:dd:d9:dd:c25:c25:300b:60f7
1252c19:dd:d9:dd:c25:c25:300b:60f8/1272c19:dd:d9:dd:c25:c25:300b:60f9
1262c19:dd:d9:dd:c25:c25:300b:60fa/1272c19:dd:d9:dd:c25:c25:300b:60fb
1272c19:dd:d9:dd:c25:c25:300b:60fc/1272c19:dd:d9:dd:c25:c25:300b:60fd
1282c19:dd:d9:dd:c25:c25:300b:60fe/1272c19:dd:d9:dd:c25:c25:300b:60ff
1292c19:dd:d9:dd:c25:c25:300b:6100/1272c19:dd:d9:dd:c25:c25:300b:6101
1302c19:dd:d9:dd:c25:c25:300b:6102/1272c19:dd:d9:dd:c25:c25:300b:6103
1312c19:dd:d9:dd:c25:c25:300b:6104/1272c19:dd:d9:dd:c25:c25:300b:6105
1322c19:dd:d9:dd:c25:c25:300b:6106/1272c19:dd:d9:dd:c25:c25:300b:6107
1332c19:dd:d9:dd:c25:c25:300b:6108/1272c19:dd:d9:dd:c25:c25:300b:6109
1342c19:dd:d9:dd:c25:c25:300b:610a/1272c19:dd:d9:dd:c25:c25:300b:610b
1352c19:dd:d9:dd:c25:c25:300b:610c/1272c19:dd:d9:dd:c25:c25:300b:610d
1362c19:dd:d9:dd:c25:c25:300b:610e/1272c19:dd:d9:dd:c25:c25:300b:610f
1372c19:dd:d9:dd:c25:c25:300b:6110/1272c19:dd:d9:dd:c25:c25:300b:6111
1382c19:dd:d9:dd:c25:c25:300b:6112/1272c19:dd:d9:dd:c25:c25:300b:6113
1392c19:dd:d9:dd:c25:c25:300b:6114/1272c19:dd:d9:dd:c25:c25:300b:6115
1402c19:dd:d9:dd:c25:c25:300b:6116/1272c19:dd:d9:dd:c25:c25:300b:6117
1412c19:dd:d9:dd:c25:c25:300b:6118/1272c19:dd:d9:dd:c25:c25:300b:6119
1422c19:dd:d9:dd:c25:c25:300b:611a/1272c19:dd:d9:dd:c25:c25:300b:611b
1432c19:dd:d9:dd:c25:c25:300b:611c/1272c19:dd:d9:dd:c25:c25:300b:611d
1442c19:dd:d9:dd:c25:c25:300b:611e/1272c19:dd:d9:dd:c25:c25:300b:611f
1452c19:dd:d9:dd:c25:c25:300b:6120/1272c19:dd:d9:dd:c25:c25:300b:6121
1462c19:dd:d9:dd:c25:c25:300b:6122/1272c19:dd:d9:dd:c25:c25:300b:6123
1472c19:dd:d9:dd:c25:c25:300b:6124/1272c19:dd:d9:dd:c25:c25:300b:6125
1482c19:dd:d9:dd:c25:c25:300b:6126/1272c19:dd:d9:dd:c25:c25:300b:6127
1492c19:dd:d9:dd:c25:c25:300b:6128/1272c19:dd:d9:dd:c25:c25:300b:6129
1502c19:dd:d9:dd:c25:c25:300b:612a/1272c19:dd:d9:dd:c25:c25:300b:612b
1512c19:dd:d9:dd:c25:c25:300b:612c/1272c19:dd:d9:dd:c25:c25:300b:612d
1522c19:dd:d9:dd:c25:c25:300b:612e/1272c19:dd:d9:dd:c25:c25:300b:612f
1532c19:dd:d9:dd:c25:c25:300b:6130/1272c19:dd:d9:dd:c25:c25:300b:6131
1542c19:dd:d9:dd:c25:c25:300b:6132/1272c19:dd:d9:dd:c25:c25:300b:6133
1552c19:dd:d9:dd:c25:c25:300b:6134/1272c19:dd:d9:dd:c25:c25:300b:6135
1562c19:dd:d9:dd:c25:c25:300b:6136/1272c19:dd:d9:dd:c25:c25:300b:6137
1572c19:dd:d9:dd:c25:c25:300b:6138/1272c19:dd:d9:dd:c25:c25:300b:6139
1582c19:dd:d9:dd:c25:c25:300b:613a/1272c19:dd:d9:dd:c25:c25:300b:613b
1592c19:dd:d9:dd:c25:c25:300b:613c/1272c19:dd:d9:dd:c25:c25:300b:613d
1602c19:dd:d9:dd:c25:c25:300b:613e/1272c19:dd:d9:dd:c25:c25:300b:613f
1612c19:dd:d9:dd:c25:c25:300b:6140/1272c19:dd:d9:dd:c25:c25:300b:6141
1622c19:dd:d9:dd:c25:c25:300b:6142/1272c19:dd:d9:dd:c25:c25:300b:6143
1632c19:dd:d9:dd:c25:c25:300b:6144/1272c19:dd:d9:dd:c25:c25:300b:6145
1642c19:dd:d9:dd:c25:c25:300b:6146/1272c19:dd:d9:dd:c25:c25:300b:6147
1652c19:dd:d9:dd:c25:c25:300b:6148/1272c19:dd:d9:dd:c25:c25:300b:6149
1662c19:dd:d9:dd:c25:c25:300b:614a/1272c19:dd:d9:dd:c25:c25:300b:614b
1672c19:dd:d9:dd:c25:c25:300b:614c/1272c19:dd:d9:dd:c25:c25:300b:614d
1682c19:dd:d9:dd:c25:c25:300b:614e/1272c19:dd:d9:dd:c25:c25:300b:614f
1692c19:dd:d9:dd:c25:c25:300b:6150/1272c19:dd:d9:dd:c25:c25:300b:6151
1702c19:dd:d9:dd:c25:c25:300b:6152/1272c19:dd:d9:dd:c25:c25:300b:6153
1712c19:dd:d9:dd:c25:c25:300b:6154/1272c19:dd:d9:dd:c25:c25:300b:6155
1722c19:dd:d9:dd:c25:c25:300b:6156/1272c19:dd:d9:dd:c25:c25:300b:6157
1732c19:dd:d9:dd:c25:c25:300b:6158/1272c19:dd:d9:dd:c25:c25:300b:6159
1742c19:dd:d9:dd:c25:c25:300b:615a/1272c19:dd:d9:dd:c25:c25:300b:615b
1752c19:dd:d9:dd:c25:c25:300b:615c/1272c19:dd:d9:dd:c25:c25:300b:615d
1762c19:dd:d9:dd:c25:c25:300b:615e/1272c19:dd:d9:dd:c25:c25:300b:615f
1772c19:dd:d9:dd:c25:c25:300b:6160/1272c19:dd:d9:dd:c25:c25:300b:6161
1782c19:dd:d9:dd:c25:c25:300b:6162/1272c19:dd:d9:dd:c25:c25:300b:6163
1792c19:dd:d9:dd:c25:c25:300b:6164/1272c19:dd:d9:dd:c25:c25:300b:6165
1802c19:dd:d9:dd:c25:c25:300b:6166/1272c19:dd:d9:dd:c25:c25:300b:6167
1812c19:dd:d9:dd:c25:c25:300b:6168/1272c19:dd:d9:dd:c25:c25:300b:6169
1822c19:dd:d9:dd:c25:c25:300b:616a/1272c19:dd:d9:dd:c25:c25:300b:616b
1832c19:dd:d9:dd:c25:c25:300b:616c/1272c19:dd:d9:dd:c25:c25:300b:616d
1842c19:dd:d9:dd:c25:c25:300b:616e/1272c19:dd:d9:dd:c25:c25:300b:616f
1852c19:dd:d9:dd:c25:c25:300b:6170/1272c19:dd:d9:dd:c25:c25:300b:6171
1862c19:dd:d9:dd:c25:c25:300b:6172/1272c19:dd:d9:dd:c25:c25:300b:6173
1872c19:dd:d9:dd:c25:c25:300b:6174/1272c19:dd:d9:dd:c25:c25:300b:6175
1882c19:dd:d9:dd:c25:c25:300b:6176/1272c19:dd:d9:dd:c25:c25:300b:6177
1892c19:dd:d9:dd:c25:c25:300b:6178/1272c19:dd:d9:dd:c25:c25:300b:6179
1902c19:dd:d9:dd:c25:c25:300b:617a/1272c19:dd:d9:dd:c25:c25:300b:617b
1912c19:dd:d9:dd:c25:c25:300b:617c/1272c19:dd:d9:dd:c25:c25:300b:617d
1922c19:dd:d9:dd:c25:c25:300b:617e/1272c19:dd:d9:dd:c25:c25:300b:617f
1932c19:dd:d9:dd:c25:c25:300b:6180/1272c19:dd:d9:dd:c25:c25:300b:6181
1942c19:dd:d9:dd:c25:c25:300b:6182/1272c19:dd:d9:dd:c25:c25:300b:6183
1952c19:dd:d9:dd:c25:c25:300b:6184/1272c19:dd:d9:dd:c25:c25:300b:6185
1962c19:dd:d9:dd:c25:c25:300b:6186/1272c19:dd:d9:dd:c25:c25:300b:6187
1972c19:dd:d9:dd:c25:c25:300b:6188/1272c19:dd:d9:dd:c25:c25:300b:6189
1982c19:dd:d9:dd:c25:c25:300b:618a/1272c19:dd:d9:dd:c25:c25:300b:618b
1992c19:dd:d9:dd:c25:c25:300b:618c/1272c19:dd:d9:dd:c25:c25:300b:618d
2002c19:dd:d9:dd:c25:c25:300b:618e/1272c19:dd:d9:dd:c25:c25:300b:618f
2012c19:dd:d9:dd:c25:c25:300b:6190/1272c19:dd:d9:dd:c25:c25:300b:6191
2022c19:dd:d9:dd:c25:c25:300b:6192/1272c19:dd:d9:dd:c25:c25:300b:6193
2032c19:dd:d9:dd:c25:c25:300b:6194/1272c19:dd:d9:dd:c25:c25:300b:6195
2042c19:dd:d9:dd:c25:c25:300b:6196/1272c19:dd:d9:dd:c25:c25:300b:6197
2052c19:dd:d9:dd:c25:c25:300b:6198/1272c19:dd:d9:dd:c25:c25:300b:6199
2062c19:dd:d9:dd:c25:c25:300b:619a/1272c19:dd:d9:dd:c25:c25:300b:619b
2072c19:dd:d9:dd:c25:c25:300b:619c/1272c19:dd:d9:dd:c25:c25:300b:619d
2082c19:dd:d9:dd:c25:c25:300b:619e/1272c19:dd:d9:dd:c25:c25:300b:619f
2092c19:dd:d9:dd:c25:c25:300b:61a0/1272c19:dd:d9:dd:c25:c25:300b:61a1
2102c19:dd:d9:dd:c25:c25:300b:61a2/1272c19:dd:d9:dd:c25:c25:300b:61a3
2112c19:dd:d9:dd:c25:c25:300b:61a4/1272c19:dd:d9:dd:c25:c25:300b:61a5
2122c19:dd:d9:dd:c25:c25:300b:61a6/1272c19:dd:d9:dd:c25:c25:300b:61a7
2132c19:dd:d9:dd:c25:c25:300b:61a8/1272c19:dd:d9:dd:c25:c25:300b:61a9
2142c19:dd:d9:dd:c25:c25:300b:61aa/1272c19:dd:d9:dd:c25:c25:300b:61ab
2152c19:dd:d9:dd:c25:c25:300b:61ac/1272c19:dd:d9:dd:c25:c25:300b:61ad
2162c19:dd:d9:dd:c25:c25:300b:61ae/1272c19:dd:d9:dd:c25:c25:300b:61af
2172c19:dd:d9:dd:c25:c25:300b:61b0/1272c19:dd:d9:dd:c25:c25:300b:61b1
2182c19:dd:d9:dd:c25:c25:300b:61b2/1272c19:dd:d9:dd:c25:c25:300b:61b3
2192c19:dd:d9:dd:c25:c25:300b:61b4/1272c19:dd:d9:dd:c25:c25:300b:61b5
2202c19:dd:d9:dd:c25:c25:300b:61b6/1272c19:dd:d9:dd:c25:c25:300b:61b7
2212c19:dd:d9:dd:c25:c25:300b:61b8/1272c19:dd:d9:dd:c25:c25:300b:61b9
2222c19:dd:d9:dd:c25:c25:300b:61ba/1272c19:dd:d9:dd:c25:c25:300b:61bb
2232c19:dd:d9:dd:c25:c25:300b:61bc/1272c19:dd:d9:dd:c25:c25:300b:61bd
2242c19:dd:d9:dd:c25:c25:300b:61be/1272c19:dd:d9:dd:c25:c25:300b:61bf
2252c19:dd:d9:dd:c25:c25:300b:61c0/1272c19:dd:d9:dd:c25:c25:300b:61c1
2262c19:dd:d9:dd:c25:c25:300b:61c2/1272c19:dd:d9:dd:c25:c25:300b:61c3
2272c19:dd:d9:dd:c25:c25:300b:61c4/1272c19:dd:d9:dd:c25:c25:300b:61c5
2282c19:dd:d9:dd:c25:c25:300b:61c6/1272c19:dd:d9:dd:c25:c25:300b:61c7
2292c19:dd:d9:dd:c25:c25:300b:61c8/1272c19:dd:d9:dd:c25:c25:300b:61c9
2302c19:dd:d9:dd:c25:c25:300b:61ca/1272c19:dd:d9:dd:c25:c25:300b:61cb
2312c19:dd:d9:dd:c25:c25:300b:61cc/1272c19:dd:d9:dd:c25:c25:300b:61cd
2322c19:dd:d9:dd:c25:c25:300b:61ce/1272c19:dd:d9:dd:c25:c25:300b:61cf
2332c19:dd:d9:dd:c25:c25:300b:61d0/1272c19:dd:d9:dd:c25:c25:300b:61d1
2342c19:dd:d9:dd:c25:c25:300b:61d2/1272c19:dd:d9:dd:c25:c25:300b:61d3
2352c19:dd:d9:dd:c25:c25:300b:61d4/1272c19:dd:d9:dd:c25:c25:300b:61d5
2362c19:dd:d9:dd:c25:c25:300b:61d6/1272c19:dd:d9:dd:c25:c25:300b:61d7
2372c19:dd:d9:dd:c25:c25:300b:61d8/1272c19:dd:d9:dd:c25:c25:300b:61d9
2382c19:dd:d9:dd:c25:c25:300b:61da/1272c19:dd:d9:dd:c25:c25:300b:61db
2392c19:dd:d9:dd:c25:c25:300b:61dc/1272c19:dd:d9:dd:c25:c25:300b:61dd
2402c19:dd:d9:dd:c25:c25:300b:61de/1272c19:dd:d9:dd:c25:c25:300b:61df
2412c19:dd:d9:dd:c25:c25:300b:61e0/1272c19:dd:d9:dd:c25:c25:300b:61e1
2422c19:dd:d9:dd:c25:c25:300b:61e2/1272c19:dd:d9:dd:c25:c25:300b:61e3
2432c19:dd:d9:dd:c25:c25:300b:61e4/1272c19:dd:d9:dd:c25:c25:300b:61e5
2442c19:dd:d9:dd:c25:c25:300b:61e6/1272c19:dd:d9:dd:c25:c25:300b:61e7
2452c19:dd:d9:dd:c25:c25:300b:61e8/1272c19:dd:d9:dd:c25:c25:300b:61e9
2462c19:dd:d9:dd:c25:c25:300b:61ea/1272c19:dd:d9:dd:c25:c25:300b:61eb
2472c19:dd:d9:dd:c25:c25:300b:61ec/1272c19:dd:d9:dd:c25:c25:300b:61ed
2482c19:dd:d9:dd:c25:c25:300b:61ee/1272c19:dd:d9:dd:c25:c25:300b:61ef
2492c19:dd:d9:dd:c25:c25:300b:61f0/1272c19:dd:d9:dd:c25:c25:300b:61f1
2502c19:dd:d9:dd:c25:c25:300b:61f2/1272c19:dd:d9:dd:c25:c25:300b:61f3
2512c19:dd:d9:dd:c25:c25:300b:61f4/1272c19:dd:d9:dd:c25:c25:300b:61f5
2522c19:dd:d9:dd:c25:c25:300b:61f6/1272c19:dd:d9:dd:c25:c25:300b:61f7
2532c19:dd:d9:dd:c25:c25:300b:61f8/1272c19:dd:d9:dd:c25:c25:300b:61f9
2542c19:dd:d9:dd:c25:c25:300b:61fa/1272c19:dd:d9:dd:c25:c25:300b:61fb
2552c19:dd:d9:dd:c25:c25:300b:61fc/1272c19:dd:d9:dd:c25:c25:300b:61fd
2562c19:dd:d9:dd:c25:c25:300b:61fe/1272c19:dd:d9:dd:c25:c25:300b:61ff

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.