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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:c25:700a:1000/116
First address
2c19:dd:d9:dd:c25:c25:700a:1000
Last address
2c19:dd:d9:dd:c25:c25:700a:1fff
Addresses
4,096
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:700a:1000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
1.a.0.0.7.5.2.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
/117 (2)/118 (4)/119 (8)/120 (16)/124 (256)/127 (2,048)/128 (4,096)

2c19:dd:d9:dd:c25:c25:700a:1000/116 makes 4,096 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:700a:1000/1282c19:dd:d9:dd:c25:c25:700a:1000
22c19:dd:d9:dd:c25:c25:700a:1001/1282c19:dd:d9:dd:c25:c25:700a:1001
32c19:dd:d9:dd:c25:c25:700a:1002/1282c19:dd:d9:dd:c25:c25:700a:1002
42c19:dd:d9:dd:c25:c25:700a:1003/1282c19:dd:d9:dd:c25:c25:700a:1003
52c19:dd:d9:dd:c25:c25:700a:1004/1282c19:dd:d9:dd:c25:c25:700a:1004
62c19:dd:d9:dd:c25:c25:700a:1005/1282c19:dd:d9:dd:c25:c25:700a:1005
72c19:dd:d9:dd:c25:c25:700a:1006/1282c19:dd:d9:dd:c25:c25:700a:1006
82c19:dd:d9:dd:c25:c25:700a:1007/1282c19:dd:d9:dd:c25:c25:700a:1007
92c19:dd:d9:dd:c25:c25:700a:1008/1282c19:dd:d9:dd:c25:c25:700a:1008
102c19:dd:d9:dd:c25:c25:700a:1009/1282c19:dd:d9:dd:c25:c25:700a:1009
112c19:dd:d9:dd:c25:c25:700a:100a/1282c19:dd:d9:dd:c25:c25:700a:100a
122c19:dd:d9:dd:c25:c25:700a:100b/1282c19:dd:d9:dd:c25:c25:700a:100b
132c19:dd:d9:dd:c25:c25:700a:100c/1282c19:dd:d9:dd:c25:c25:700a:100c
142c19:dd:d9:dd:c25:c25:700a:100d/1282c19:dd:d9:dd:c25:c25:700a:100d
152c19:dd:d9:dd:c25:c25:700a:100e/1282c19:dd:d9:dd:c25:c25:700a:100e
162c19:dd:d9:dd:c25:c25:700a:100f/1282c19:dd:d9:dd:c25:c25:700a:100f
172c19:dd:d9:dd:c25:c25:700a:1010/1282c19:dd:d9:dd:c25:c25:700a:1010
182c19:dd:d9:dd:c25:c25:700a:1011/1282c19:dd:d9:dd:c25:c25:700a:1011
192c19:dd:d9:dd:c25:c25:700a:1012/1282c19:dd:d9:dd:c25:c25:700a:1012
202c19:dd:d9:dd:c25:c25:700a:1013/1282c19:dd:d9:dd:c25:c25:700a:1013
212c19:dd:d9:dd:c25:c25:700a:1014/1282c19:dd:d9:dd:c25:c25:700a:1014
222c19:dd:d9:dd:c25:c25:700a:1015/1282c19:dd:d9:dd:c25:c25:700a:1015
232c19:dd:d9:dd:c25:c25:700a:1016/1282c19:dd:d9:dd:c25:c25:700a:1016
242c19:dd:d9:dd:c25:c25:700a:1017/1282c19:dd:d9:dd:c25:c25:700a:1017
252c19:dd:d9:dd:c25:c25:700a:1018/1282c19:dd:d9:dd:c25:c25:700a:1018
262c19:dd:d9:dd:c25:c25:700a:1019/1282c19:dd:d9:dd:c25:c25:700a:1019
272c19:dd:d9:dd:c25:c25:700a:101a/1282c19:dd:d9:dd:c25:c25:700a:101a
282c19:dd:d9:dd:c25:c25:700a:101b/1282c19:dd:d9:dd:c25:c25:700a:101b
292c19:dd:d9:dd:c25:c25:700a:101c/1282c19:dd:d9:dd:c25:c25:700a:101c
302c19:dd:d9:dd:c25:c25:700a:101d/1282c19:dd:d9:dd:c25:c25:700a:101d
312c19:dd:d9:dd:c25:c25:700a:101e/1282c19:dd:d9:dd:c25:c25:700a:101e
322c19:dd:d9:dd:c25:c25:700a:101f/1282c19:dd:d9:dd:c25:c25:700a:101f
332c19:dd:d9:dd:c25:c25:700a:1020/1282c19:dd:d9:dd:c25:c25:700a:1020
342c19:dd:d9:dd:c25:c25:700a:1021/1282c19:dd:d9:dd:c25:c25:700a:1021
352c19:dd:d9:dd:c25:c25:700a:1022/1282c19:dd:d9:dd:c25:c25:700a:1022
362c19:dd:d9:dd:c25:c25:700a:1023/1282c19:dd:d9:dd:c25:c25:700a:1023
372c19:dd:d9:dd:c25:c25:700a:1024/1282c19:dd:d9:dd:c25:c25:700a:1024
382c19:dd:d9:dd:c25:c25:700a:1025/1282c19:dd:d9:dd:c25:c25:700a:1025
392c19:dd:d9:dd:c25:c25:700a:1026/1282c19:dd:d9:dd:c25:c25:700a:1026
402c19:dd:d9:dd:c25:c25:700a:1027/1282c19:dd:d9:dd:c25:c25:700a:1027
412c19:dd:d9:dd:c25:c25:700a:1028/1282c19:dd:d9:dd:c25:c25:700a:1028
422c19:dd:d9:dd:c25:c25:700a:1029/1282c19:dd:d9:dd:c25:c25:700a:1029
432c19:dd:d9:dd:c25:c25:700a:102a/1282c19:dd:d9:dd:c25:c25:700a:102a
442c19:dd:d9:dd:c25:c25:700a:102b/1282c19:dd:d9:dd:c25:c25:700a:102b
452c19:dd:d9:dd:c25:c25:700a:102c/1282c19:dd:d9:dd:c25:c25:700a:102c
462c19:dd:d9:dd:c25:c25:700a:102d/1282c19:dd:d9:dd:c25:c25:700a:102d
472c19:dd:d9:dd:c25:c25:700a:102e/1282c19:dd:d9:dd:c25:c25:700a:102e
482c19:dd:d9:dd:c25:c25:700a:102f/1282c19:dd:d9:dd:c25:c25:700a:102f
492c19:dd:d9:dd:c25:c25:700a:1030/1282c19:dd:d9:dd:c25:c25:700a:1030
502c19:dd:d9:dd:c25:c25:700a:1031/1282c19:dd:d9:dd:c25:c25:700a:1031
512c19:dd:d9:dd:c25:c25:700a:1032/1282c19:dd:d9:dd:c25:c25:700a:1032
522c19:dd:d9:dd:c25:c25:700a:1033/1282c19:dd:d9:dd:c25:c25:700a:1033
532c19:dd:d9:dd:c25:c25:700a:1034/1282c19:dd:d9:dd:c25:c25:700a:1034
542c19:dd:d9:dd:c25:c25:700a:1035/1282c19:dd:d9:dd:c25:c25:700a:1035
552c19:dd:d9:dd:c25:c25:700a:1036/1282c19:dd:d9:dd:c25:c25:700a:1036
562c19:dd:d9:dd:c25:c25:700a:1037/1282c19:dd:d9:dd:c25:c25:700a:1037
572c19:dd:d9:dd:c25:c25:700a:1038/1282c19:dd:d9:dd:c25:c25:700a:1038
582c19:dd:d9:dd:c25:c25:700a:1039/1282c19:dd:d9:dd:c25:c25:700a:1039
592c19:dd:d9:dd:c25:c25:700a:103a/1282c19:dd:d9:dd:c25:c25:700a:103a
602c19:dd:d9:dd:c25:c25:700a:103b/1282c19:dd:d9:dd:c25:c25:700a:103b
612c19:dd:d9:dd:c25:c25:700a:103c/1282c19:dd:d9:dd:c25:c25:700a:103c
622c19:dd:d9:dd:c25:c25:700a:103d/1282c19:dd:d9:dd:c25:c25:700a:103d
632c19:dd:d9:dd:c25:c25:700a:103e/1282c19:dd:d9:dd:c25:c25:700a:103e
642c19:dd:d9:dd:c25:c25:700a:103f/1282c19:dd:d9:dd:c25:c25:700a:103f
652c19:dd:d9:dd:c25:c25:700a:1040/1282c19:dd:d9:dd:c25:c25:700a:1040
662c19:dd:d9:dd:c25:c25:700a:1041/1282c19:dd:d9:dd:c25:c25:700a:1041
672c19:dd:d9:dd:c25:c25:700a:1042/1282c19:dd:d9:dd:c25:c25:700a:1042
682c19:dd:d9:dd:c25:c25:700a:1043/1282c19:dd:d9:dd:c25:c25:700a:1043
692c19:dd:d9:dd:c25:c25:700a:1044/1282c19:dd:d9:dd:c25:c25:700a:1044
702c19:dd:d9:dd:c25:c25:700a:1045/1282c19:dd:d9:dd:c25:c25:700a:1045
712c19:dd:d9:dd:c25:c25:700a:1046/1282c19:dd:d9:dd:c25:c25:700a:1046
722c19:dd:d9:dd:c25:c25:700a:1047/1282c19:dd:d9:dd:c25:c25:700a:1047
732c19:dd:d9:dd:c25:c25:700a:1048/1282c19:dd:d9:dd:c25:c25:700a:1048
742c19:dd:d9:dd:c25:c25:700a:1049/1282c19:dd:d9:dd:c25:c25:700a:1049
752c19:dd:d9:dd:c25:c25:700a:104a/1282c19:dd:d9:dd:c25:c25:700a:104a
762c19:dd:d9:dd:c25:c25:700a:104b/1282c19:dd:d9:dd:c25:c25:700a:104b
772c19:dd:d9:dd:c25:c25:700a:104c/1282c19:dd:d9:dd:c25:c25:700a:104c
782c19:dd:d9:dd:c25:c25:700a:104d/1282c19:dd:d9:dd:c25:c25:700a:104d
792c19:dd:d9:dd:c25:c25:700a:104e/1282c19:dd:d9:dd:c25:c25:700a:104e
802c19:dd:d9:dd:c25:c25:700a:104f/1282c19:dd:d9:dd:c25:c25:700a:104f
812c19:dd:d9:dd:c25:c25:700a:1050/1282c19:dd:d9:dd:c25:c25:700a:1050
822c19:dd:d9:dd:c25:c25:700a:1051/1282c19:dd:d9:dd:c25:c25:700a:1051
832c19:dd:d9:dd:c25:c25:700a:1052/1282c19:dd:d9:dd:c25:c25:700a:1052
842c19:dd:d9:dd:c25:c25:700a:1053/1282c19:dd:d9:dd:c25:c25:700a:1053
852c19:dd:d9:dd:c25:c25:700a:1054/1282c19:dd:d9:dd:c25:c25:700a:1054
862c19:dd:d9:dd:c25:c25:700a:1055/1282c19:dd:d9:dd:c25:c25:700a:1055
872c19:dd:d9:dd:c25:c25:700a:1056/1282c19:dd:d9:dd:c25:c25:700a:1056
882c19:dd:d9:dd:c25:c25:700a:1057/1282c19:dd:d9:dd:c25:c25:700a:1057
892c19:dd:d9:dd:c25:c25:700a:1058/1282c19:dd:d9:dd:c25:c25:700a:1058
902c19:dd:d9:dd:c25:c25:700a:1059/1282c19:dd:d9:dd:c25:c25:700a:1059
912c19:dd:d9:dd:c25:c25:700a:105a/1282c19:dd:d9:dd:c25:c25:700a:105a
922c19:dd:d9:dd:c25:c25:700a:105b/1282c19:dd:d9:dd:c25:c25:700a:105b
932c19:dd:d9:dd:c25:c25:700a:105c/1282c19:dd:d9:dd:c25:c25:700a:105c
942c19:dd:d9:dd:c25:c25:700a:105d/1282c19:dd:d9:dd:c25:c25:700a:105d
952c19:dd:d9:dd:c25:c25:700a:105e/1282c19:dd:d9:dd:c25:c25:700a:105e
962c19:dd:d9:dd:c25:c25:700a:105f/1282c19:dd:d9:dd:c25:c25:700a:105f
972c19:dd:d9:dd:c25:c25:700a:1060/1282c19:dd:d9:dd:c25:c25:700a:1060
982c19:dd:d9:dd:c25:c25:700a:1061/1282c19:dd:d9:dd:c25:c25:700a:1061
992c19:dd:d9:dd:c25:c25:700a:1062/1282c19:dd:d9:dd:c25:c25:700a:1062
1002c19:dd:d9:dd:c25:c25:700a:1063/1282c19:dd:d9:dd:c25:c25:700a:1063
1012c19:dd:d9:dd:c25:c25:700a:1064/1282c19:dd:d9:dd:c25:c25:700a:1064
1022c19:dd:d9:dd:c25:c25:700a:1065/1282c19:dd:d9:dd:c25:c25:700a:1065
1032c19:dd:d9:dd:c25:c25:700a:1066/1282c19:dd:d9:dd:c25:c25:700a:1066
1042c19:dd:d9:dd:c25:c25:700a:1067/1282c19:dd:d9:dd:c25:c25:700a:1067
1052c19:dd:d9:dd:c25:c25:700a:1068/1282c19:dd:d9:dd:c25:c25:700a:1068
1062c19:dd:d9:dd:c25:c25:700a:1069/1282c19:dd:d9:dd:c25:c25:700a:1069
1072c19:dd:d9:dd:c25:c25:700a:106a/1282c19:dd:d9:dd:c25:c25:700a:106a
1082c19:dd:d9:dd:c25:c25:700a:106b/1282c19:dd:d9:dd:c25:c25:700a:106b
1092c19:dd:d9:dd:c25:c25:700a:106c/1282c19:dd:d9:dd:c25:c25:700a:106c
1102c19:dd:d9:dd:c25:c25:700a:106d/1282c19:dd:d9:dd:c25:c25:700a:106d
1112c19:dd:d9:dd:c25:c25:700a:106e/1282c19:dd:d9:dd:c25:c25:700a:106e
1122c19:dd:d9:dd:c25:c25:700a:106f/1282c19:dd:d9:dd:c25:c25:700a:106f
1132c19:dd:d9:dd:c25:c25:700a:1070/1282c19:dd:d9:dd:c25:c25:700a:1070
1142c19:dd:d9:dd:c25:c25:700a:1071/1282c19:dd:d9:dd:c25:c25:700a:1071
1152c19:dd:d9:dd:c25:c25:700a:1072/1282c19:dd:d9:dd:c25:c25:700a:1072
1162c19:dd:d9:dd:c25:c25:700a:1073/1282c19:dd:d9:dd:c25:c25:700a:1073
1172c19:dd:d9:dd:c25:c25:700a:1074/1282c19:dd:d9:dd:c25:c25:700a:1074
1182c19:dd:d9:dd:c25:c25:700a:1075/1282c19:dd:d9:dd:c25:c25:700a:1075
1192c19:dd:d9:dd:c25:c25:700a:1076/1282c19:dd:d9:dd:c25:c25:700a:1076
1202c19:dd:d9:dd:c25:c25:700a:1077/1282c19:dd:d9:dd:c25:c25:700a:1077
1212c19:dd:d9:dd:c25:c25:700a:1078/1282c19:dd:d9:dd:c25:c25:700a:1078
1222c19:dd:d9:dd:c25:c25:700a:1079/1282c19:dd:d9:dd:c25:c25:700a:1079
1232c19:dd:d9:dd:c25:c25:700a:107a/1282c19:dd:d9:dd:c25:c25:700a:107a
1242c19:dd:d9:dd:c25:c25:700a:107b/1282c19:dd:d9:dd:c25:c25:700a:107b
1252c19:dd:d9:dd:c25:c25:700a:107c/1282c19:dd:d9:dd:c25:c25:700a:107c
1262c19:dd:d9:dd:c25:c25:700a:107d/1282c19:dd:d9:dd:c25:c25:700a:107d
1272c19:dd:d9:dd:c25:c25:700a:107e/1282c19:dd:d9:dd:c25:c25:700a:107e
1282c19:dd:d9:dd:c25:c25:700a:107f/1282c19:dd:d9:dd:c25:c25:700a:107f
1292c19:dd:d9:dd:c25:c25:700a:1080/1282c19:dd:d9:dd:c25:c25:700a:1080
1302c19:dd:d9:dd:c25:c25:700a:1081/1282c19:dd:d9:dd:c25:c25:700a:1081
1312c19:dd:d9:dd:c25:c25:700a:1082/1282c19:dd:d9:dd:c25:c25:700a:1082
1322c19:dd:d9:dd:c25:c25:700a:1083/1282c19:dd:d9:dd:c25:c25:700a:1083
1332c19:dd:d9:dd:c25:c25:700a:1084/1282c19:dd:d9:dd:c25:c25:700a:1084
1342c19:dd:d9:dd:c25:c25:700a:1085/1282c19:dd:d9:dd:c25:c25:700a:1085
1352c19:dd:d9:dd:c25:c25:700a:1086/1282c19:dd:d9:dd:c25:c25:700a:1086
1362c19:dd:d9:dd:c25:c25:700a:1087/1282c19:dd:d9:dd:c25:c25:700a:1087
1372c19:dd:d9:dd:c25:c25:700a:1088/1282c19:dd:d9:dd:c25:c25:700a:1088
1382c19:dd:d9:dd:c25:c25:700a:1089/1282c19:dd:d9:dd:c25:c25:700a:1089
1392c19:dd:d9:dd:c25:c25:700a:108a/1282c19:dd:d9:dd:c25:c25:700a:108a
1402c19:dd:d9:dd:c25:c25:700a:108b/1282c19:dd:d9:dd:c25:c25:700a:108b
1412c19:dd:d9:dd:c25:c25:700a:108c/1282c19:dd:d9:dd:c25:c25:700a:108c
1422c19:dd:d9:dd:c25:c25:700a:108d/1282c19:dd:d9:dd:c25:c25:700a:108d
1432c19:dd:d9:dd:c25:c25:700a:108e/1282c19:dd:d9:dd:c25:c25:700a:108e
1442c19:dd:d9:dd:c25:c25:700a:108f/1282c19:dd:d9:dd:c25:c25:700a:108f
1452c19:dd:d9:dd:c25:c25:700a:1090/1282c19:dd:d9:dd:c25:c25:700a:1090
1462c19:dd:d9:dd:c25:c25:700a:1091/1282c19:dd:d9:dd:c25:c25:700a:1091
1472c19:dd:d9:dd:c25:c25:700a:1092/1282c19:dd:d9:dd:c25:c25:700a:1092
1482c19:dd:d9:dd:c25:c25:700a:1093/1282c19:dd:d9:dd:c25:c25:700a:1093
1492c19:dd:d9:dd:c25:c25:700a:1094/1282c19:dd:d9:dd:c25:c25:700a:1094
1502c19:dd:d9:dd:c25:c25:700a:1095/1282c19:dd:d9:dd:c25:c25:700a:1095
1512c19:dd:d9:dd:c25:c25:700a:1096/1282c19:dd:d9:dd:c25:c25:700a:1096
1522c19:dd:d9:dd:c25:c25:700a:1097/1282c19:dd:d9:dd:c25:c25:700a:1097
1532c19:dd:d9:dd:c25:c25:700a:1098/1282c19:dd:d9:dd:c25:c25:700a:1098
1542c19:dd:d9:dd:c25:c25:700a:1099/1282c19:dd:d9:dd:c25:c25:700a:1099
1552c19:dd:d9:dd:c25:c25:700a:109a/1282c19:dd:d9:dd:c25:c25:700a:109a
1562c19:dd:d9:dd:c25:c25:700a:109b/1282c19:dd:d9:dd:c25:c25:700a:109b
1572c19:dd:d9:dd:c25:c25:700a:109c/1282c19:dd:d9:dd:c25:c25:700a:109c
1582c19:dd:d9:dd:c25:c25:700a:109d/1282c19:dd:d9:dd:c25:c25:700a:109d
1592c19:dd:d9:dd:c25:c25:700a:109e/1282c19:dd:d9:dd:c25:c25:700a:109e
1602c19:dd:d9:dd:c25:c25:700a:109f/1282c19:dd:d9:dd:c25:c25:700a:109f
1612c19:dd:d9:dd:c25:c25:700a:10a0/1282c19:dd:d9:dd:c25:c25:700a:10a0
1622c19:dd:d9:dd:c25:c25:700a:10a1/1282c19:dd:d9:dd:c25:c25:700a:10a1
1632c19:dd:d9:dd:c25:c25:700a:10a2/1282c19:dd:d9:dd:c25:c25:700a:10a2
1642c19:dd:d9:dd:c25:c25:700a:10a3/1282c19:dd:d9:dd:c25:c25:700a:10a3
1652c19:dd:d9:dd:c25:c25:700a:10a4/1282c19:dd:d9:dd:c25:c25:700a:10a4
1662c19:dd:d9:dd:c25:c25:700a:10a5/1282c19:dd:d9:dd:c25:c25:700a:10a5
1672c19:dd:d9:dd:c25:c25:700a:10a6/1282c19:dd:d9:dd:c25:c25:700a:10a6
1682c19:dd:d9:dd:c25:c25:700a:10a7/1282c19:dd:d9:dd:c25:c25:700a:10a7
1692c19:dd:d9:dd:c25:c25:700a:10a8/1282c19:dd:d9:dd:c25:c25:700a:10a8
1702c19:dd:d9:dd:c25:c25:700a:10a9/1282c19:dd:d9:dd:c25:c25:700a:10a9
1712c19:dd:d9:dd:c25:c25:700a:10aa/1282c19:dd:d9:dd:c25:c25:700a:10aa
1722c19:dd:d9:dd:c25:c25:700a:10ab/1282c19:dd:d9:dd:c25:c25:700a:10ab
1732c19:dd:d9:dd:c25:c25:700a:10ac/1282c19:dd:d9:dd:c25:c25:700a:10ac
1742c19:dd:d9:dd:c25:c25:700a:10ad/1282c19:dd:d9:dd:c25:c25:700a:10ad
1752c19:dd:d9:dd:c25:c25:700a:10ae/1282c19:dd:d9:dd:c25:c25:700a:10ae
1762c19:dd:d9:dd:c25:c25:700a:10af/1282c19:dd:d9:dd:c25:c25:700a:10af
1772c19:dd:d9:dd:c25:c25:700a:10b0/1282c19:dd:d9:dd:c25:c25:700a:10b0
1782c19:dd:d9:dd:c25:c25:700a:10b1/1282c19:dd:d9:dd:c25:c25:700a:10b1
1792c19:dd:d9:dd:c25:c25:700a:10b2/1282c19:dd:d9:dd:c25:c25:700a:10b2
1802c19:dd:d9:dd:c25:c25:700a:10b3/1282c19:dd:d9:dd:c25:c25:700a:10b3
1812c19:dd:d9:dd:c25:c25:700a:10b4/1282c19:dd:d9:dd:c25:c25:700a:10b4
1822c19:dd:d9:dd:c25:c25:700a:10b5/1282c19:dd:d9:dd:c25:c25:700a:10b5
1832c19:dd:d9:dd:c25:c25:700a:10b6/1282c19:dd:d9:dd:c25:c25:700a:10b6
1842c19:dd:d9:dd:c25:c25:700a:10b7/1282c19:dd:d9:dd:c25:c25:700a:10b7
1852c19:dd:d9:dd:c25:c25:700a:10b8/1282c19:dd:d9:dd:c25:c25:700a:10b8
1862c19:dd:d9:dd:c25:c25:700a:10b9/1282c19:dd:d9:dd:c25:c25:700a:10b9
1872c19:dd:d9:dd:c25:c25:700a:10ba/1282c19:dd:d9:dd:c25:c25:700a:10ba
1882c19:dd:d9:dd:c25:c25:700a:10bb/1282c19:dd:d9:dd:c25:c25:700a:10bb
1892c19:dd:d9:dd:c25:c25:700a:10bc/1282c19:dd:d9:dd:c25:c25:700a:10bc
1902c19:dd:d9:dd:c25:c25:700a:10bd/1282c19:dd:d9:dd:c25:c25:700a:10bd
1912c19:dd:d9:dd:c25:c25:700a:10be/1282c19:dd:d9:dd:c25:c25:700a:10be
1922c19:dd:d9:dd:c25:c25:700a:10bf/1282c19:dd:d9:dd:c25:c25:700a:10bf
1932c19:dd:d9:dd:c25:c25:700a:10c0/1282c19:dd:d9:dd:c25:c25:700a:10c0
1942c19:dd:d9:dd:c25:c25:700a:10c1/1282c19:dd:d9:dd:c25:c25:700a:10c1
1952c19:dd:d9:dd:c25:c25:700a:10c2/1282c19:dd:d9:dd:c25:c25:700a:10c2
1962c19:dd:d9:dd:c25:c25:700a:10c3/1282c19:dd:d9:dd:c25:c25:700a:10c3
1972c19:dd:d9:dd:c25:c25:700a:10c4/1282c19:dd:d9:dd:c25:c25:700a:10c4
1982c19:dd:d9:dd:c25:c25:700a:10c5/1282c19:dd:d9:dd:c25:c25:700a:10c5
1992c19:dd:d9:dd:c25:c25:700a:10c6/1282c19:dd:d9:dd:c25:c25:700a:10c6
2002c19:dd:d9:dd:c25:c25:700a:10c7/1282c19:dd:d9:dd:c25:c25:700a:10c7
2012c19:dd:d9:dd:c25:c25:700a:10c8/1282c19:dd:d9:dd:c25:c25:700a:10c8
2022c19:dd:d9:dd:c25:c25:700a:10c9/1282c19:dd:d9:dd:c25:c25:700a:10c9
2032c19:dd:d9:dd:c25:c25:700a:10ca/1282c19:dd:d9:dd:c25:c25:700a:10ca
2042c19:dd:d9:dd:c25:c25:700a:10cb/1282c19:dd:d9:dd:c25:c25:700a:10cb
2052c19:dd:d9:dd:c25:c25:700a:10cc/1282c19:dd:d9:dd:c25:c25:700a:10cc
2062c19:dd:d9:dd:c25:c25:700a:10cd/1282c19:dd:d9:dd:c25:c25:700a:10cd
2072c19:dd:d9:dd:c25:c25:700a:10ce/1282c19:dd:d9:dd:c25:c25:700a:10ce
2082c19:dd:d9:dd:c25:c25:700a:10cf/1282c19:dd:d9:dd:c25:c25:700a:10cf
2092c19:dd:d9:dd:c25:c25:700a:10d0/1282c19:dd:d9:dd:c25:c25:700a:10d0
2102c19:dd:d9:dd:c25:c25:700a:10d1/1282c19:dd:d9:dd:c25:c25:700a:10d1
2112c19:dd:d9:dd:c25:c25:700a:10d2/1282c19:dd:d9:dd:c25:c25:700a:10d2
2122c19:dd:d9:dd:c25:c25:700a:10d3/1282c19:dd:d9:dd:c25:c25:700a:10d3
2132c19:dd:d9:dd:c25:c25:700a:10d4/1282c19:dd:d9:dd:c25:c25:700a:10d4
2142c19:dd:d9:dd:c25:c25:700a:10d5/1282c19:dd:d9:dd:c25:c25:700a:10d5
2152c19:dd:d9:dd:c25:c25:700a:10d6/1282c19:dd:d9:dd:c25:c25:700a:10d6
2162c19:dd:d9:dd:c25:c25:700a:10d7/1282c19:dd:d9:dd:c25:c25:700a:10d7
2172c19:dd:d9:dd:c25:c25:700a:10d8/1282c19:dd:d9:dd:c25:c25:700a:10d8
2182c19:dd:d9:dd:c25:c25:700a:10d9/1282c19:dd:d9:dd:c25:c25:700a:10d9
2192c19:dd:d9:dd:c25:c25:700a:10da/1282c19:dd:d9:dd:c25:c25:700a:10da
2202c19:dd:d9:dd:c25:c25:700a:10db/1282c19:dd:d9:dd:c25:c25:700a:10db
2212c19:dd:d9:dd:c25:c25:700a:10dc/1282c19:dd:d9:dd:c25:c25:700a:10dc
2222c19:dd:d9:dd:c25:c25:700a:10dd/1282c19:dd:d9:dd:c25:c25:700a:10dd
2232c19:dd:d9:dd:c25:c25:700a:10de/1282c19:dd:d9:dd:c25:c25:700a:10de
2242c19:dd:d9:dd:c25:c25:700a:10df/1282c19:dd:d9:dd:c25:c25:700a:10df
2252c19:dd:d9:dd:c25:c25:700a:10e0/1282c19:dd:d9:dd:c25:c25:700a:10e0
2262c19:dd:d9:dd:c25:c25:700a:10e1/1282c19:dd:d9:dd:c25:c25:700a:10e1
2272c19:dd:d9:dd:c25:c25:700a:10e2/1282c19:dd:d9:dd:c25:c25:700a:10e2
2282c19:dd:d9:dd:c25:c25:700a:10e3/1282c19:dd:d9:dd:c25:c25:700a:10e3
2292c19:dd:d9:dd:c25:c25:700a:10e4/1282c19:dd:d9:dd:c25:c25:700a:10e4
2302c19:dd:d9:dd:c25:c25:700a:10e5/1282c19:dd:d9:dd:c25:c25:700a:10e5
2312c19:dd:d9:dd:c25:c25:700a:10e6/1282c19:dd:d9:dd:c25:c25:700a:10e6
2322c19:dd:d9:dd:c25:c25:700a:10e7/1282c19:dd:d9:dd:c25:c25:700a:10e7
2332c19:dd:d9:dd:c25:c25:700a:10e8/1282c19:dd:d9:dd:c25:c25:700a:10e8
2342c19:dd:d9:dd:c25:c25:700a:10e9/1282c19:dd:d9:dd:c25:c25:700a:10e9
2352c19:dd:d9:dd:c25:c25:700a:10ea/1282c19:dd:d9:dd:c25:c25:700a:10ea
2362c19:dd:d9:dd:c25:c25:700a:10eb/1282c19:dd:d9:dd:c25:c25:700a:10eb
2372c19:dd:d9:dd:c25:c25:700a:10ec/1282c19:dd:d9:dd:c25:c25:700a:10ec
2382c19:dd:d9:dd:c25:c25:700a:10ed/1282c19:dd:d9:dd:c25:c25:700a:10ed
2392c19:dd:d9:dd:c25:c25:700a:10ee/1282c19:dd:d9:dd:c25:c25:700a:10ee
2402c19:dd:d9:dd:c25:c25:700a:10ef/1282c19:dd:d9:dd:c25:c25:700a:10ef
2412c19:dd:d9:dd:c25:c25:700a:10f0/1282c19:dd:d9:dd:c25:c25:700a:10f0
2422c19:dd:d9:dd:c25:c25:700a:10f1/1282c19:dd:d9:dd:c25:c25:700a:10f1
2432c19:dd:d9:dd:c25:c25:700a:10f2/1282c19:dd:d9:dd:c25:c25:700a:10f2
2442c19:dd:d9:dd:c25:c25:700a:10f3/1282c19:dd:d9:dd:c25:c25:700a:10f3
2452c19:dd:d9:dd:c25:c25:700a:10f4/1282c19:dd:d9:dd:c25:c25:700a:10f4
2462c19:dd:d9:dd:c25:c25:700a:10f5/1282c19:dd:d9:dd:c25:c25:700a:10f5
2472c19:dd:d9:dd:c25:c25:700a:10f6/1282c19:dd:d9:dd:c25:c25:700a:10f6
2482c19:dd:d9:dd:c25:c25:700a:10f7/1282c19:dd:d9:dd:c25:c25:700a:10f7
2492c19:dd:d9:dd:c25:c25:700a:10f8/1282c19:dd:d9:dd:c25:c25:700a:10f8
2502c19:dd:d9:dd:c25:c25:700a:10f9/1282c19:dd:d9:dd:c25:c25:700a:10f9
2512c19:dd:d9:dd:c25:c25:700a:10fa/1282c19:dd:d9:dd:c25:c25:700a:10fa
2522c19:dd:d9:dd:c25:c25:700a:10fb/1282c19:dd:d9:dd:c25:c25:700a:10fb
2532c19:dd:d9:dd:c25:c25:700a:10fc/1282c19:dd:d9:dd:c25:c25:700a:10fc
2542c19:dd:d9:dd:c25:c25:700a:10fd/1282c19:dd:d9:dd:c25:c25:700a:10fd
2552c19:dd:d9:dd:c25:c25:700a:10fe/1282c19:dd:d9:dd:c25:c25:700a:10fe
2562c19:dd:d9:dd:c25:c25:700a:10ff/1282c19:dd:d9:dd:c25:c25:700a:10ff

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.