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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:d915:ea00/119
First address
2c19:dd:d9:dd:c25:c25:d915:ea00
Last address
2c19:dd:d9:dd:c25:c25:d915:ebff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:ea00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
a.e.5.1.9.d.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
b.e.5.1.9.d.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
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/127
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:d915:ea00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:ea00/1272c19:dd:d9:dd:c25:c25:d915:ea01
22c19:dd:d9:dd:c25:c25:d915:ea02/1272c19:dd:d9:dd:c25:c25:d915:ea03
32c19:dd:d9:dd:c25:c25:d915:ea04/1272c19:dd:d9:dd:c25:c25:d915:ea05
42c19:dd:d9:dd:c25:c25:d915:ea06/1272c19:dd:d9:dd:c25:c25:d915:ea07
52c19:dd:d9:dd:c25:c25:d915:ea08/1272c19:dd:d9:dd:c25:c25:d915:ea09
62c19:dd:d9:dd:c25:c25:d915:ea0a/1272c19:dd:d9:dd:c25:c25:d915:ea0b
72c19:dd:d9:dd:c25:c25:d915:ea0c/1272c19:dd:d9:dd:c25:c25:d915:ea0d
82c19:dd:d9:dd:c25:c25:d915:ea0e/1272c19:dd:d9:dd:c25:c25:d915:ea0f
92c19:dd:d9:dd:c25:c25:d915:ea10/1272c19:dd:d9:dd:c25:c25:d915:ea11
102c19:dd:d9:dd:c25:c25:d915:ea12/1272c19:dd:d9:dd:c25:c25:d915:ea13
112c19:dd:d9:dd:c25:c25:d915:ea14/1272c19:dd:d9:dd:c25:c25:d915:ea15
122c19:dd:d9:dd:c25:c25:d915:ea16/1272c19:dd:d9:dd:c25:c25:d915:ea17
132c19:dd:d9:dd:c25:c25:d915:ea18/1272c19:dd:d9:dd:c25:c25:d915:ea19
142c19:dd:d9:dd:c25:c25:d915:ea1a/1272c19:dd:d9:dd:c25:c25:d915:ea1b
152c19:dd:d9:dd:c25:c25:d915:ea1c/1272c19:dd:d9:dd:c25:c25:d915:ea1d
162c19:dd:d9:dd:c25:c25:d915:ea1e/1272c19:dd:d9:dd:c25:c25:d915:ea1f
172c19:dd:d9:dd:c25:c25:d915:ea20/1272c19:dd:d9:dd:c25:c25:d915:ea21
182c19:dd:d9:dd:c25:c25:d915:ea22/1272c19:dd:d9:dd:c25:c25:d915:ea23
192c19:dd:d9:dd:c25:c25:d915:ea24/1272c19:dd:d9:dd:c25:c25:d915:ea25
202c19:dd:d9:dd:c25:c25:d915:ea26/1272c19:dd:d9:dd:c25:c25:d915:ea27
212c19:dd:d9:dd:c25:c25:d915:ea28/1272c19:dd:d9:dd:c25:c25:d915:ea29
222c19:dd:d9:dd:c25:c25:d915:ea2a/1272c19:dd:d9:dd:c25:c25:d915:ea2b
232c19:dd:d9:dd:c25:c25:d915:ea2c/1272c19:dd:d9:dd:c25:c25:d915:ea2d
242c19:dd:d9:dd:c25:c25:d915:ea2e/1272c19:dd:d9:dd:c25:c25:d915:ea2f
252c19:dd:d9:dd:c25:c25:d915:ea30/1272c19:dd:d9:dd:c25:c25:d915:ea31
262c19:dd:d9:dd:c25:c25:d915:ea32/1272c19:dd:d9:dd:c25:c25:d915:ea33
272c19:dd:d9:dd:c25:c25:d915:ea34/1272c19:dd:d9:dd:c25:c25:d915:ea35
282c19:dd:d9:dd:c25:c25:d915:ea36/1272c19:dd:d9:dd:c25:c25:d915:ea37
292c19:dd:d9:dd:c25:c25:d915:ea38/1272c19:dd:d9:dd:c25:c25:d915:ea39
302c19:dd:d9:dd:c25:c25:d915:ea3a/1272c19:dd:d9:dd:c25:c25:d915:ea3b
312c19:dd:d9:dd:c25:c25:d915:ea3c/1272c19:dd:d9:dd:c25:c25:d915:ea3d
322c19:dd:d9:dd:c25:c25:d915:ea3e/1272c19:dd:d9:dd:c25:c25:d915:ea3f
332c19:dd:d9:dd:c25:c25:d915:ea40/1272c19:dd:d9:dd:c25:c25:d915:ea41
342c19:dd:d9:dd:c25:c25:d915:ea42/1272c19:dd:d9:dd:c25:c25:d915:ea43
352c19:dd:d9:dd:c25:c25:d915:ea44/1272c19:dd:d9:dd:c25:c25:d915:ea45
362c19:dd:d9:dd:c25:c25:d915:ea46/1272c19:dd:d9:dd:c25:c25:d915:ea47
372c19:dd:d9:dd:c25:c25:d915:ea48/1272c19:dd:d9:dd:c25:c25:d915:ea49
382c19:dd:d9:dd:c25:c25:d915:ea4a/1272c19:dd:d9:dd:c25:c25:d915:ea4b
392c19:dd:d9:dd:c25:c25:d915:ea4c/1272c19:dd:d9:dd:c25:c25:d915:ea4d
402c19:dd:d9:dd:c25:c25:d915:ea4e/1272c19:dd:d9:dd:c25:c25:d915:ea4f
412c19:dd:d9:dd:c25:c25:d915:ea50/1272c19:dd:d9:dd:c25:c25:d915:ea51
422c19:dd:d9:dd:c25:c25:d915:ea52/1272c19:dd:d9:dd:c25:c25:d915:ea53
432c19:dd:d9:dd:c25:c25:d915:ea54/1272c19:dd:d9:dd:c25:c25:d915:ea55
442c19:dd:d9:dd:c25:c25:d915:ea56/1272c19:dd:d9:dd:c25:c25:d915:ea57
452c19:dd:d9:dd:c25:c25:d915:ea58/1272c19:dd:d9:dd:c25:c25:d915:ea59
462c19:dd:d9:dd:c25:c25:d915:ea5a/1272c19:dd:d9:dd:c25:c25:d915:ea5b
472c19:dd:d9:dd:c25:c25:d915:ea5c/1272c19:dd:d9:dd:c25:c25:d915:ea5d
482c19:dd:d9:dd:c25:c25:d915:ea5e/1272c19:dd:d9:dd:c25:c25:d915:ea5f
492c19:dd:d9:dd:c25:c25:d915:ea60/1272c19:dd:d9:dd:c25:c25:d915:ea61
502c19:dd:d9:dd:c25:c25:d915:ea62/1272c19:dd:d9:dd:c25:c25:d915:ea63
512c19:dd:d9:dd:c25:c25:d915:ea64/1272c19:dd:d9:dd:c25:c25:d915:ea65
522c19:dd:d9:dd:c25:c25:d915:ea66/1272c19:dd:d9:dd:c25:c25:d915:ea67
532c19:dd:d9:dd:c25:c25:d915:ea68/1272c19:dd:d9:dd:c25:c25:d915:ea69
542c19:dd:d9:dd:c25:c25:d915:ea6a/1272c19:dd:d9:dd:c25:c25:d915:ea6b
552c19:dd:d9:dd:c25:c25:d915:ea6c/1272c19:dd:d9:dd:c25:c25:d915:ea6d
562c19:dd:d9:dd:c25:c25:d915:ea6e/1272c19:dd:d9:dd:c25:c25:d915:ea6f
572c19:dd:d9:dd:c25:c25:d915:ea70/1272c19:dd:d9:dd:c25:c25:d915:ea71
582c19:dd:d9:dd:c25:c25:d915:ea72/1272c19:dd:d9:dd:c25:c25:d915:ea73
592c19:dd:d9:dd:c25:c25:d915:ea74/1272c19:dd:d9:dd:c25:c25:d915:ea75
602c19:dd:d9:dd:c25:c25:d915:ea76/1272c19:dd:d9:dd:c25:c25:d915:ea77
612c19:dd:d9:dd:c25:c25:d915:ea78/1272c19:dd:d9:dd:c25:c25:d915:ea79
622c19:dd:d9:dd:c25:c25:d915:ea7a/1272c19:dd:d9:dd:c25:c25:d915:ea7b
632c19:dd:d9:dd:c25:c25:d915:ea7c/1272c19:dd:d9:dd:c25:c25:d915:ea7d
642c19:dd:d9:dd:c25:c25:d915:ea7e/1272c19:dd:d9:dd:c25:c25:d915:ea7f
652c19:dd:d9:dd:c25:c25:d915:ea80/1272c19:dd:d9:dd:c25:c25:d915:ea81
662c19:dd:d9:dd:c25:c25:d915:ea82/1272c19:dd:d9:dd:c25:c25:d915:ea83
672c19:dd:d9:dd:c25:c25:d915:ea84/1272c19:dd:d9:dd:c25:c25:d915:ea85
682c19:dd:d9:dd:c25:c25:d915:ea86/1272c19:dd:d9:dd:c25:c25:d915:ea87
692c19:dd:d9:dd:c25:c25:d915:ea88/1272c19:dd:d9:dd:c25:c25:d915:ea89
702c19:dd:d9:dd:c25:c25:d915:ea8a/1272c19:dd:d9:dd:c25:c25:d915:ea8b
712c19:dd:d9:dd:c25:c25:d915:ea8c/1272c19:dd:d9:dd:c25:c25:d915:ea8d
722c19:dd:d9:dd:c25:c25:d915:ea8e/1272c19:dd:d9:dd:c25:c25:d915:ea8f
732c19:dd:d9:dd:c25:c25:d915:ea90/1272c19:dd:d9:dd:c25:c25:d915:ea91
742c19:dd:d9:dd:c25:c25:d915:ea92/1272c19:dd:d9:dd:c25:c25:d915:ea93
752c19:dd:d9:dd:c25:c25:d915:ea94/1272c19:dd:d9:dd:c25:c25:d915:ea95
762c19:dd:d9:dd:c25:c25:d915:ea96/1272c19:dd:d9:dd:c25:c25:d915:ea97
772c19:dd:d9:dd:c25:c25:d915:ea98/1272c19:dd:d9:dd:c25:c25:d915:ea99
782c19:dd:d9:dd:c25:c25:d915:ea9a/1272c19:dd:d9:dd:c25:c25:d915:ea9b
792c19:dd:d9:dd:c25:c25:d915:ea9c/1272c19:dd:d9:dd:c25:c25:d915:ea9d
802c19:dd:d9:dd:c25:c25:d915:ea9e/1272c19:dd:d9:dd:c25:c25:d915:ea9f
812c19:dd:d9:dd:c25:c25:d915:eaa0/1272c19:dd:d9:dd:c25:c25:d915:eaa1
822c19:dd:d9:dd:c25:c25:d915:eaa2/1272c19:dd:d9:dd:c25:c25:d915:eaa3
832c19:dd:d9:dd:c25:c25:d915:eaa4/1272c19:dd:d9:dd:c25:c25:d915:eaa5
842c19:dd:d9:dd:c25:c25:d915:eaa6/1272c19:dd:d9:dd:c25:c25:d915:eaa7
852c19:dd:d9:dd:c25:c25:d915:eaa8/1272c19:dd:d9:dd:c25:c25:d915:eaa9
862c19:dd:d9:dd:c25:c25:d915:eaaa/1272c19:dd:d9:dd:c25:c25:d915:eaab
872c19:dd:d9:dd:c25:c25:d915:eaac/1272c19:dd:d9:dd:c25:c25:d915:eaad
882c19:dd:d9:dd:c25:c25:d915:eaae/1272c19:dd:d9:dd:c25:c25:d915:eaaf
892c19:dd:d9:dd:c25:c25:d915:eab0/1272c19:dd:d9:dd:c25:c25:d915:eab1
902c19:dd:d9:dd:c25:c25:d915:eab2/1272c19:dd:d9:dd:c25:c25:d915:eab3
912c19:dd:d9:dd:c25:c25:d915:eab4/1272c19:dd:d9:dd:c25:c25:d915:eab5
922c19:dd:d9:dd:c25:c25:d915:eab6/1272c19:dd:d9:dd:c25:c25:d915:eab7
932c19:dd:d9:dd:c25:c25:d915:eab8/1272c19:dd:d9:dd:c25:c25:d915:eab9
942c19:dd:d9:dd:c25:c25:d915:eaba/1272c19:dd:d9:dd:c25:c25:d915:eabb
952c19:dd:d9:dd:c25:c25:d915:eabc/1272c19:dd:d9:dd:c25:c25:d915:eabd
962c19:dd:d9:dd:c25:c25:d915:eabe/1272c19:dd:d9:dd:c25:c25:d915:eabf
972c19:dd:d9:dd:c25:c25:d915:eac0/1272c19:dd:d9:dd:c25:c25:d915:eac1
982c19:dd:d9:dd:c25:c25:d915:eac2/1272c19:dd:d9:dd:c25:c25:d915:eac3
992c19:dd:d9:dd:c25:c25:d915:eac4/1272c19:dd:d9:dd:c25:c25:d915:eac5
1002c19:dd:d9:dd:c25:c25:d915:eac6/1272c19:dd:d9:dd:c25:c25:d915:eac7
1012c19:dd:d9:dd:c25:c25:d915:eac8/1272c19:dd:d9:dd:c25:c25:d915:eac9
1022c19:dd:d9:dd:c25:c25:d915:eaca/1272c19:dd:d9:dd:c25:c25:d915:eacb
1032c19:dd:d9:dd:c25:c25:d915:eacc/1272c19:dd:d9:dd:c25:c25:d915:eacd
1042c19:dd:d9:dd:c25:c25:d915:eace/1272c19:dd:d9:dd:c25:c25:d915:eacf
1052c19:dd:d9:dd:c25:c25:d915:ead0/1272c19:dd:d9:dd:c25:c25:d915:ead1
1062c19:dd:d9:dd:c25:c25:d915:ead2/1272c19:dd:d9:dd:c25:c25:d915:ead3
1072c19:dd:d9:dd:c25:c25:d915:ead4/1272c19:dd:d9:dd:c25:c25:d915:ead5
1082c19:dd:d9:dd:c25:c25:d915:ead6/1272c19:dd:d9:dd:c25:c25:d915:ead7
1092c19:dd:d9:dd:c25:c25:d915:ead8/1272c19:dd:d9:dd:c25:c25:d915:ead9
1102c19:dd:d9:dd:c25:c25:d915:eada/1272c19:dd:d9:dd:c25:c25:d915:eadb
1112c19:dd:d9:dd:c25:c25:d915:eadc/1272c19:dd:d9:dd:c25:c25:d915:eadd
1122c19:dd:d9:dd:c25:c25:d915:eade/1272c19:dd:d9:dd:c25:c25:d915:eadf
1132c19:dd:d9:dd:c25:c25:d915:eae0/1272c19:dd:d9:dd:c25:c25:d915:eae1
1142c19:dd:d9:dd:c25:c25:d915:eae2/1272c19:dd:d9:dd:c25:c25:d915:eae3
1152c19:dd:d9:dd:c25:c25:d915:eae4/1272c19:dd:d9:dd:c25:c25:d915:eae5
1162c19:dd:d9:dd:c25:c25:d915:eae6/1272c19:dd:d9:dd:c25:c25:d915:eae7
1172c19:dd:d9:dd:c25:c25:d915:eae8/1272c19:dd:d9:dd:c25:c25:d915:eae9
1182c19:dd:d9:dd:c25:c25:d915:eaea/1272c19:dd:d9:dd:c25:c25:d915:eaeb
1192c19:dd:d9:dd:c25:c25:d915:eaec/1272c19:dd:d9:dd:c25:c25:d915:eaed
1202c19:dd:d9:dd:c25:c25:d915:eaee/1272c19:dd:d9:dd:c25:c25:d915:eaef
1212c19:dd:d9:dd:c25:c25:d915:eaf0/1272c19:dd:d9:dd:c25:c25:d915:eaf1
1222c19:dd:d9:dd:c25:c25:d915:eaf2/1272c19:dd:d9:dd:c25:c25:d915:eaf3
1232c19:dd:d9:dd:c25:c25:d915:eaf4/1272c19:dd:d9:dd:c25:c25:d915:eaf5
1242c19:dd:d9:dd:c25:c25:d915:eaf6/1272c19:dd:d9:dd:c25:c25:d915:eaf7
1252c19:dd:d9:dd:c25:c25:d915:eaf8/1272c19:dd:d9:dd:c25:c25:d915:eaf9
1262c19:dd:d9:dd:c25:c25:d915:eafa/1272c19:dd:d9:dd:c25:c25:d915:eafb
1272c19:dd:d9:dd:c25:c25:d915:eafc/1272c19:dd:d9:dd:c25:c25:d915:eafd
1282c19:dd:d9:dd:c25:c25:d915:eafe/1272c19:dd:d9:dd:c25:c25:d915:eaff
1292c19:dd:d9:dd:c25:c25:d915:eb00/1272c19:dd:d9:dd:c25:c25:d915:eb01
1302c19:dd:d9:dd:c25:c25:d915:eb02/1272c19:dd:d9:dd:c25:c25:d915:eb03
1312c19:dd:d9:dd:c25:c25:d915:eb04/1272c19:dd:d9:dd:c25:c25:d915:eb05
1322c19:dd:d9:dd:c25:c25:d915:eb06/1272c19:dd:d9:dd:c25:c25:d915:eb07
1332c19:dd:d9:dd:c25:c25:d915:eb08/1272c19:dd:d9:dd:c25:c25:d915:eb09
1342c19:dd:d9:dd:c25:c25:d915:eb0a/1272c19:dd:d9:dd:c25:c25:d915:eb0b
1352c19:dd:d9:dd:c25:c25:d915:eb0c/1272c19:dd:d9:dd:c25:c25:d915:eb0d
1362c19:dd:d9:dd:c25:c25:d915:eb0e/1272c19:dd:d9:dd:c25:c25:d915:eb0f
1372c19:dd:d9:dd:c25:c25:d915:eb10/1272c19:dd:d9:dd:c25:c25:d915:eb11
1382c19:dd:d9:dd:c25:c25:d915:eb12/1272c19:dd:d9:dd:c25:c25:d915:eb13
1392c19:dd:d9:dd:c25:c25:d915:eb14/1272c19:dd:d9:dd:c25:c25:d915:eb15
1402c19:dd:d9:dd:c25:c25:d915:eb16/1272c19:dd:d9:dd:c25:c25:d915:eb17
1412c19:dd:d9:dd:c25:c25:d915:eb18/1272c19:dd:d9:dd:c25:c25:d915:eb19
1422c19:dd:d9:dd:c25:c25:d915:eb1a/1272c19:dd:d9:dd:c25:c25:d915:eb1b
1432c19:dd:d9:dd:c25:c25:d915:eb1c/1272c19:dd:d9:dd:c25:c25:d915:eb1d
1442c19:dd:d9:dd:c25:c25:d915:eb1e/1272c19:dd:d9:dd:c25:c25:d915:eb1f
1452c19:dd:d9:dd:c25:c25:d915:eb20/1272c19:dd:d9:dd:c25:c25:d915:eb21
1462c19:dd:d9:dd:c25:c25:d915:eb22/1272c19:dd:d9:dd:c25:c25:d915:eb23
1472c19:dd:d9:dd:c25:c25:d915:eb24/1272c19:dd:d9:dd:c25:c25:d915:eb25
1482c19:dd:d9:dd:c25:c25:d915:eb26/1272c19:dd:d9:dd:c25:c25:d915:eb27
1492c19:dd:d9:dd:c25:c25:d915:eb28/1272c19:dd:d9:dd:c25:c25:d915:eb29
1502c19:dd:d9:dd:c25:c25:d915:eb2a/1272c19:dd:d9:dd:c25:c25:d915:eb2b
1512c19:dd:d9:dd:c25:c25:d915:eb2c/1272c19:dd:d9:dd:c25:c25:d915:eb2d
1522c19:dd:d9:dd:c25:c25:d915:eb2e/1272c19:dd:d9:dd:c25:c25:d915:eb2f
1532c19:dd:d9:dd:c25:c25:d915:eb30/1272c19:dd:d9:dd:c25:c25:d915:eb31
1542c19:dd:d9:dd:c25:c25:d915:eb32/1272c19:dd:d9:dd:c25:c25:d915:eb33
1552c19:dd:d9:dd:c25:c25:d915:eb34/1272c19:dd:d9:dd:c25:c25:d915:eb35
1562c19:dd:d9:dd:c25:c25:d915:eb36/1272c19:dd:d9:dd:c25:c25:d915:eb37
1572c19:dd:d9:dd:c25:c25:d915:eb38/1272c19:dd:d9:dd:c25:c25:d915:eb39
1582c19:dd:d9:dd:c25:c25:d915:eb3a/1272c19:dd:d9:dd:c25:c25:d915:eb3b
1592c19:dd:d9:dd:c25:c25:d915:eb3c/1272c19:dd:d9:dd:c25:c25:d915:eb3d
1602c19:dd:d9:dd:c25:c25:d915:eb3e/1272c19:dd:d9:dd:c25:c25:d915:eb3f
1612c19:dd:d9:dd:c25:c25:d915:eb40/1272c19:dd:d9:dd:c25:c25:d915:eb41
1622c19:dd:d9:dd:c25:c25:d915:eb42/1272c19:dd:d9:dd:c25:c25:d915:eb43
1632c19:dd:d9:dd:c25:c25:d915:eb44/1272c19:dd:d9:dd:c25:c25:d915:eb45
1642c19:dd:d9:dd:c25:c25:d915:eb46/1272c19:dd:d9:dd:c25:c25:d915:eb47
1652c19:dd:d9:dd:c25:c25:d915:eb48/1272c19:dd:d9:dd:c25:c25:d915:eb49
1662c19:dd:d9:dd:c25:c25:d915:eb4a/1272c19:dd:d9:dd:c25:c25:d915:eb4b
1672c19:dd:d9:dd:c25:c25:d915:eb4c/1272c19:dd:d9:dd:c25:c25:d915:eb4d
1682c19:dd:d9:dd:c25:c25:d915:eb4e/1272c19:dd:d9:dd:c25:c25:d915:eb4f
1692c19:dd:d9:dd:c25:c25:d915:eb50/1272c19:dd:d9:dd:c25:c25:d915:eb51
1702c19:dd:d9:dd:c25:c25:d915:eb52/1272c19:dd:d9:dd:c25:c25:d915:eb53
1712c19:dd:d9:dd:c25:c25:d915:eb54/1272c19:dd:d9:dd:c25:c25:d915:eb55
1722c19:dd:d9:dd:c25:c25:d915:eb56/1272c19:dd:d9:dd:c25:c25:d915:eb57
1732c19:dd:d9:dd:c25:c25:d915:eb58/1272c19:dd:d9:dd:c25:c25:d915:eb59
1742c19:dd:d9:dd:c25:c25:d915:eb5a/1272c19:dd:d9:dd:c25:c25:d915:eb5b
1752c19:dd:d9:dd:c25:c25:d915:eb5c/1272c19:dd:d9:dd:c25:c25:d915:eb5d
1762c19:dd:d9:dd:c25:c25:d915:eb5e/1272c19:dd:d9:dd:c25:c25:d915:eb5f
1772c19:dd:d9:dd:c25:c25:d915:eb60/1272c19:dd:d9:dd:c25:c25:d915:eb61
1782c19:dd:d9:dd:c25:c25:d915:eb62/1272c19:dd:d9:dd:c25:c25:d915:eb63
1792c19:dd:d9:dd:c25:c25:d915:eb64/1272c19:dd:d9:dd:c25:c25:d915:eb65
1802c19:dd:d9:dd:c25:c25:d915:eb66/1272c19:dd:d9:dd:c25:c25:d915:eb67
1812c19:dd:d9:dd:c25:c25:d915:eb68/1272c19:dd:d9:dd:c25:c25:d915:eb69
1822c19:dd:d9:dd:c25:c25:d915:eb6a/1272c19:dd:d9:dd:c25:c25:d915:eb6b
1832c19:dd:d9:dd:c25:c25:d915:eb6c/1272c19:dd:d9:dd:c25:c25:d915:eb6d
1842c19:dd:d9:dd:c25:c25:d915:eb6e/1272c19:dd:d9:dd:c25:c25:d915:eb6f
1852c19:dd:d9:dd:c25:c25:d915:eb70/1272c19:dd:d9:dd:c25:c25:d915:eb71
1862c19:dd:d9:dd:c25:c25:d915:eb72/1272c19:dd:d9:dd:c25:c25:d915:eb73
1872c19:dd:d9:dd:c25:c25:d915:eb74/1272c19:dd:d9:dd:c25:c25:d915:eb75
1882c19:dd:d9:dd:c25:c25:d915:eb76/1272c19:dd:d9:dd:c25:c25:d915:eb77
1892c19:dd:d9:dd:c25:c25:d915:eb78/1272c19:dd:d9:dd:c25:c25:d915:eb79
1902c19:dd:d9:dd:c25:c25:d915:eb7a/1272c19:dd:d9:dd:c25:c25:d915:eb7b
1912c19:dd:d9:dd:c25:c25:d915:eb7c/1272c19:dd:d9:dd:c25:c25:d915:eb7d
1922c19:dd:d9:dd:c25:c25:d915:eb7e/1272c19:dd:d9:dd:c25:c25:d915:eb7f
1932c19:dd:d9:dd:c25:c25:d915:eb80/1272c19:dd:d9:dd:c25:c25:d915:eb81
1942c19:dd:d9:dd:c25:c25:d915:eb82/1272c19:dd:d9:dd:c25:c25:d915:eb83
1952c19:dd:d9:dd:c25:c25:d915:eb84/1272c19:dd:d9:dd:c25:c25:d915:eb85
1962c19:dd:d9:dd:c25:c25:d915:eb86/1272c19:dd:d9:dd:c25:c25:d915:eb87
1972c19:dd:d9:dd:c25:c25:d915:eb88/1272c19:dd:d9:dd:c25:c25:d915:eb89
1982c19:dd:d9:dd:c25:c25:d915:eb8a/1272c19:dd:d9:dd:c25:c25:d915:eb8b
1992c19:dd:d9:dd:c25:c25:d915:eb8c/1272c19:dd:d9:dd:c25:c25:d915:eb8d
2002c19:dd:d9:dd:c25:c25:d915:eb8e/1272c19:dd:d9:dd:c25:c25:d915:eb8f
2012c19:dd:d9:dd:c25:c25:d915:eb90/1272c19:dd:d9:dd:c25:c25:d915:eb91
2022c19:dd:d9:dd:c25:c25:d915:eb92/1272c19:dd:d9:dd:c25:c25:d915:eb93
2032c19:dd:d9:dd:c25:c25:d915:eb94/1272c19:dd:d9:dd:c25:c25:d915:eb95
2042c19:dd:d9:dd:c25:c25:d915:eb96/1272c19:dd:d9:dd:c25:c25:d915:eb97
2052c19:dd:d9:dd:c25:c25:d915:eb98/1272c19:dd:d9:dd:c25:c25:d915:eb99
2062c19:dd:d9:dd:c25:c25:d915:eb9a/1272c19:dd:d9:dd:c25:c25:d915:eb9b
2072c19:dd:d9:dd:c25:c25:d915:eb9c/1272c19:dd:d9:dd:c25:c25:d915:eb9d
2082c19:dd:d9:dd:c25:c25:d915:eb9e/1272c19:dd:d9:dd:c25:c25:d915:eb9f
2092c19:dd:d9:dd:c25:c25:d915:eba0/1272c19:dd:d9:dd:c25:c25:d915:eba1
2102c19:dd:d9:dd:c25:c25:d915:eba2/1272c19:dd:d9:dd:c25:c25:d915:eba3
2112c19:dd:d9:dd:c25:c25:d915:eba4/1272c19:dd:d9:dd:c25:c25:d915:eba5
2122c19:dd:d9:dd:c25:c25:d915:eba6/1272c19:dd:d9:dd:c25:c25:d915:eba7
2132c19:dd:d9:dd:c25:c25:d915:eba8/1272c19:dd:d9:dd:c25:c25:d915:eba9
2142c19:dd:d9:dd:c25:c25:d915:ebaa/1272c19:dd:d9:dd:c25:c25:d915:ebab
2152c19:dd:d9:dd:c25:c25:d915:ebac/1272c19:dd:d9:dd:c25:c25:d915:ebad
2162c19:dd:d9:dd:c25:c25:d915:ebae/1272c19:dd:d9:dd:c25:c25:d915:ebaf
2172c19:dd:d9:dd:c25:c25:d915:ebb0/1272c19:dd:d9:dd:c25:c25:d915:ebb1
2182c19:dd:d9:dd:c25:c25:d915:ebb2/1272c19:dd:d9:dd:c25:c25:d915:ebb3
2192c19:dd:d9:dd:c25:c25:d915:ebb4/1272c19:dd:d9:dd:c25:c25:d915:ebb5
2202c19:dd:d9:dd:c25:c25:d915:ebb6/1272c19:dd:d9:dd:c25:c25:d915:ebb7
2212c19:dd:d9:dd:c25:c25:d915:ebb8/1272c19:dd:d9:dd:c25:c25:d915:ebb9
2222c19:dd:d9:dd:c25:c25:d915:ebba/1272c19:dd:d9:dd:c25:c25:d915:ebbb
2232c19:dd:d9:dd:c25:c25:d915:ebbc/1272c19:dd:d9:dd:c25:c25:d915:ebbd
2242c19:dd:d9:dd:c25:c25:d915:ebbe/1272c19:dd:d9:dd:c25:c25:d915:ebbf
2252c19:dd:d9:dd:c25:c25:d915:ebc0/1272c19:dd:d9:dd:c25:c25:d915:ebc1
2262c19:dd:d9:dd:c25:c25:d915:ebc2/1272c19:dd:d9:dd:c25:c25:d915:ebc3
2272c19:dd:d9:dd:c25:c25:d915:ebc4/1272c19:dd:d9:dd:c25:c25:d915:ebc5
2282c19:dd:d9:dd:c25:c25:d915:ebc6/1272c19:dd:d9:dd:c25:c25:d915:ebc7
2292c19:dd:d9:dd:c25:c25:d915:ebc8/1272c19:dd:d9:dd:c25:c25:d915:ebc9
2302c19:dd:d9:dd:c25:c25:d915:ebca/1272c19:dd:d9:dd:c25:c25:d915:ebcb
2312c19:dd:d9:dd:c25:c25:d915:ebcc/1272c19:dd:d9:dd:c25:c25:d915:ebcd
2322c19:dd:d9:dd:c25:c25:d915:ebce/1272c19:dd:d9:dd:c25:c25:d915:ebcf
2332c19:dd:d9:dd:c25:c25:d915:ebd0/1272c19:dd:d9:dd:c25:c25:d915:ebd1
2342c19:dd:d9:dd:c25:c25:d915:ebd2/1272c19:dd:d9:dd:c25:c25:d915:ebd3
2352c19:dd:d9:dd:c25:c25:d915:ebd4/1272c19:dd:d9:dd:c25:c25:d915:ebd5
2362c19:dd:d9:dd:c25:c25:d915:ebd6/1272c19:dd:d9:dd:c25:c25:d915:ebd7
2372c19:dd:d9:dd:c25:c25:d915:ebd8/1272c19:dd:d9:dd:c25:c25:d915:ebd9
2382c19:dd:d9:dd:c25:c25:d915:ebda/1272c19:dd:d9:dd:c25:c25:d915:ebdb
2392c19:dd:d9:dd:c25:c25:d915:ebdc/1272c19:dd:d9:dd:c25:c25:d915:ebdd
2402c19:dd:d9:dd:c25:c25:d915:ebde/1272c19:dd:d9:dd:c25:c25:d915:ebdf
2412c19:dd:d9:dd:c25:c25:d915:ebe0/1272c19:dd:d9:dd:c25:c25:d915:ebe1
2422c19:dd:d9:dd:c25:c25:d915:ebe2/1272c19:dd:d9:dd:c25:c25:d915:ebe3
2432c19:dd:d9:dd:c25:c25:d915:ebe4/1272c19:dd:d9:dd:c25:c25:d915:ebe5
2442c19:dd:d9:dd:c25:c25:d915:ebe6/1272c19:dd:d9:dd:c25:c25:d915:ebe7
2452c19:dd:d9:dd:c25:c25:d915:ebe8/1272c19:dd:d9:dd:c25:c25:d915:ebe9
2462c19:dd:d9:dd:c25:c25:d915:ebea/1272c19:dd:d9:dd:c25:c25:d915:ebeb
2472c19:dd:d9:dd:c25:c25:d915:ebec/1272c19:dd:d9:dd:c25:c25:d915:ebed
2482c19:dd:d9:dd:c25:c25:d915:ebee/1272c19:dd:d9:dd:c25:c25:d915:ebef
2492c19:dd:d9:dd:c25:c25:d915:ebf0/1272c19:dd:d9:dd:c25:c25:d915:ebf1
2502c19:dd:d9:dd:c25:c25:d915:ebf2/1272c19:dd:d9:dd:c25:c25:d915:ebf3
2512c19:dd:d9:dd:c25:c25:d915:ebf4/1272c19:dd:d9:dd:c25:c25:d915:ebf5
2522c19:dd:d9:dd:c25:c25:d915:ebf6/1272c19:dd:d9:dd:c25:c25:d915:ebf7
2532c19:dd:d9:dd:c25:c25:d915:ebf8/1272c19:dd:d9:dd:c25:c25:d915:ebf9
2542c19:dd:d9:dd:c25:c25:d915:ebfa/1272c19:dd:d9:dd:c25:c25:d915:ebfb
2552c19:dd:d9:dd:c25:c25:d915:ebfc/1272c19:dd:d9:dd:c25:c25:d915:ebfd
2562c19:dd:d9:dd:c25:c25:d915:ebfe/1272c19:dd:d9:dd:c25:c25:d915:ebff

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.