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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:c25:c25:dd:dd:dd:ba00/119
First address
2c19:dd:c25:c25:dd:dd:dd:ba00
Last address
2c19:dd:c25:c25:dd:dd:dd:bbff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:0c25:00dd:00dd:00dd:ba00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
a.b.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
b.b.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.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:c25:c25:dd:dd:dd:ba00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:c25:c25:dd:dd:dd:ba00/1272c19:dd:c25:c25:dd:dd:dd:ba01
22c19:dd:c25:c25:dd:dd:dd:ba02/1272c19:dd:c25:c25:dd:dd:dd:ba03
32c19:dd:c25:c25:dd:dd:dd:ba04/1272c19:dd:c25:c25:dd:dd:dd:ba05
42c19:dd:c25:c25:dd:dd:dd:ba06/1272c19:dd:c25:c25:dd:dd:dd:ba07
52c19:dd:c25:c25:dd:dd:dd:ba08/1272c19:dd:c25:c25:dd:dd:dd:ba09
62c19:dd:c25:c25:dd:dd:dd:ba0a/1272c19:dd:c25:c25:dd:dd:dd:ba0b
72c19:dd:c25:c25:dd:dd:dd:ba0c/1272c19:dd:c25:c25:dd:dd:dd:ba0d
82c19:dd:c25:c25:dd:dd:dd:ba0e/1272c19:dd:c25:c25:dd:dd:dd:ba0f
92c19:dd:c25:c25:dd:dd:dd:ba10/1272c19:dd:c25:c25:dd:dd:dd:ba11
102c19:dd:c25:c25:dd:dd:dd:ba12/1272c19:dd:c25:c25:dd:dd:dd:ba13
112c19:dd:c25:c25:dd:dd:dd:ba14/1272c19:dd:c25:c25:dd:dd:dd:ba15
122c19:dd:c25:c25:dd:dd:dd:ba16/1272c19:dd:c25:c25:dd:dd:dd:ba17
132c19:dd:c25:c25:dd:dd:dd:ba18/1272c19:dd:c25:c25:dd:dd:dd:ba19
142c19:dd:c25:c25:dd:dd:dd:ba1a/1272c19:dd:c25:c25:dd:dd:dd:ba1b
152c19:dd:c25:c25:dd:dd:dd:ba1c/1272c19:dd:c25:c25:dd:dd:dd:ba1d
162c19:dd:c25:c25:dd:dd:dd:ba1e/1272c19:dd:c25:c25:dd:dd:dd:ba1f
172c19:dd:c25:c25:dd:dd:dd:ba20/1272c19:dd:c25:c25:dd:dd:dd:ba21
182c19:dd:c25:c25:dd:dd:dd:ba22/1272c19:dd:c25:c25:dd:dd:dd:ba23
192c19:dd:c25:c25:dd:dd:dd:ba24/1272c19:dd:c25:c25:dd:dd:dd:ba25
202c19:dd:c25:c25:dd:dd:dd:ba26/1272c19:dd:c25:c25:dd:dd:dd:ba27
212c19:dd:c25:c25:dd:dd:dd:ba28/1272c19:dd:c25:c25:dd:dd:dd:ba29
222c19:dd:c25:c25:dd:dd:dd:ba2a/1272c19:dd:c25:c25:dd:dd:dd:ba2b
232c19:dd:c25:c25:dd:dd:dd:ba2c/1272c19:dd:c25:c25:dd:dd:dd:ba2d
242c19:dd:c25:c25:dd:dd:dd:ba2e/1272c19:dd:c25:c25:dd:dd:dd:ba2f
252c19:dd:c25:c25:dd:dd:dd:ba30/1272c19:dd:c25:c25:dd:dd:dd:ba31
262c19:dd:c25:c25:dd:dd:dd:ba32/1272c19:dd:c25:c25:dd:dd:dd:ba33
272c19:dd:c25:c25:dd:dd:dd:ba34/1272c19:dd:c25:c25:dd:dd:dd:ba35
282c19:dd:c25:c25:dd:dd:dd:ba36/1272c19:dd:c25:c25:dd:dd:dd:ba37
292c19:dd:c25:c25:dd:dd:dd:ba38/1272c19:dd:c25:c25:dd:dd:dd:ba39
302c19:dd:c25:c25:dd:dd:dd:ba3a/1272c19:dd:c25:c25:dd:dd:dd:ba3b
312c19:dd:c25:c25:dd:dd:dd:ba3c/1272c19:dd:c25:c25:dd:dd:dd:ba3d
322c19:dd:c25:c25:dd:dd:dd:ba3e/1272c19:dd:c25:c25:dd:dd:dd:ba3f
332c19:dd:c25:c25:dd:dd:dd:ba40/1272c19:dd:c25:c25:dd:dd:dd:ba41
342c19:dd:c25:c25:dd:dd:dd:ba42/1272c19:dd:c25:c25:dd:dd:dd:ba43
352c19:dd:c25:c25:dd:dd:dd:ba44/1272c19:dd:c25:c25:dd:dd:dd:ba45
362c19:dd:c25:c25:dd:dd:dd:ba46/1272c19:dd:c25:c25:dd:dd:dd:ba47
372c19:dd:c25:c25:dd:dd:dd:ba48/1272c19:dd:c25:c25:dd:dd:dd:ba49
382c19:dd:c25:c25:dd:dd:dd:ba4a/1272c19:dd:c25:c25:dd:dd:dd:ba4b
392c19:dd:c25:c25:dd:dd:dd:ba4c/1272c19:dd:c25:c25:dd:dd:dd:ba4d
402c19:dd:c25:c25:dd:dd:dd:ba4e/1272c19:dd:c25:c25:dd:dd:dd:ba4f
412c19:dd:c25:c25:dd:dd:dd:ba50/1272c19:dd:c25:c25:dd:dd:dd:ba51
422c19:dd:c25:c25:dd:dd:dd:ba52/1272c19:dd:c25:c25:dd:dd:dd:ba53
432c19:dd:c25:c25:dd:dd:dd:ba54/1272c19:dd:c25:c25:dd:dd:dd:ba55
442c19:dd:c25:c25:dd:dd:dd:ba56/1272c19:dd:c25:c25:dd:dd:dd:ba57
452c19:dd:c25:c25:dd:dd:dd:ba58/1272c19:dd:c25:c25:dd:dd:dd:ba59
462c19:dd:c25:c25:dd:dd:dd:ba5a/1272c19:dd:c25:c25:dd:dd:dd:ba5b
472c19:dd:c25:c25:dd:dd:dd:ba5c/1272c19:dd:c25:c25:dd:dd:dd:ba5d
482c19:dd:c25:c25:dd:dd:dd:ba5e/1272c19:dd:c25:c25:dd:dd:dd:ba5f
492c19:dd:c25:c25:dd:dd:dd:ba60/1272c19:dd:c25:c25:dd:dd:dd:ba61
502c19:dd:c25:c25:dd:dd:dd:ba62/1272c19:dd:c25:c25:dd:dd:dd:ba63
512c19:dd:c25:c25:dd:dd:dd:ba64/1272c19:dd:c25:c25:dd:dd:dd:ba65
522c19:dd:c25:c25:dd:dd:dd:ba66/1272c19:dd:c25:c25:dd:dd:dd:ba67
532c19:dd:c25:c25:dd:dd:dd:ba68/1272c19:dd:c25:c25:dd:dd:dd:ba69
542c19:dd:c25:c25:dd:dd:dd:ba6a/1272c19:dd:c25:c25:dd:dd:dd:ba6b
552c19:dd:c25:c25:dd:dd:dd:ba6c/1272c19:dd:c25:c25:dd:dd:dd:ba6d
562c19:dd:c25:c25:dd:dd:dd:ba6e/1272c19:dd:c25:c25:dd:dd:dd:ba6f
572c19:dd:c25:c25:dd:dd:dd:ba70/1272c19:dd:c25:c25:dd:dd:dd:ba71
582c19:dd:c25:c25:dd:dd:dd:ba72/1272c19:dd:c25:c25:dd:dd:dd:ba73
592c19:dd:c25:c25:dd:dd:dd:ba74/1272c19:dd:c25:c25:dd:dd:dd:ba75
602c19:dd:c25:c25:dd:dd:dd:ba76/1272c19:dd:c25:c25:dd:dd:dd:ba77
612c19:dd:c25:c25:dd:dd:dd:ba78/1272c19:dd:c25:c25:dd:dd:dd:ba79
622c19:dd:c25:c25:dd:dd:dd:ba7a/1272c19:dd:c25:c25:dd:dd:dd:ba7b
632c19:dd:c25:c25:dd:dd:dd:ba7c/1272c19:dd:c25:c25:dd:dd:dd:ba7d
642c19:dd:c25:c25:dd:dd:dd:ba7e/1272c19:dd:c25:c25:dd:dd:dd:ba7f
652c19:dd:c25:c25:dd:dd:dd:ba80/1272c19:dd:c25:c25:dd:dd:dd:ba81
662c19:dd:c25:c25:dd:dd:dd:ba82/1272c19:dd:c25:c25:dd:dd:dd:ba83
672c19:dd:c25:c25:dd:dd:dd:ba84/1272c19:dd:c25:c25:dd:dd:dd:ba85
682c19:dd:c25:c25:dd:dd:dd:ba86/1272c19:dd:c25:c25:dd:dd:dd:ba87
692c19:dd:c25:c25:dd:dd:dd:ba88/1272c19:dd:c25:c25:dd:dd:dd:ba89
702c19:dd:c25:c25:dd:dd:dd:ba8a/1272c19:dd:c25:c25:dd:dd:dd:ba8b
712c19:dd:c25:c25:dd:dd:dd:ba8c/1272c19:dd:c25:c25:dd:dd:dd:ba8d
722c19:dd:c25:c25:dd:dd:dd:ba8e/1272c19:dd:c25:c25:dd:dd:dd:ba8f
732c19:dd:c25:c25:dd:dd:dd:ba90/1272c19:dd:c25:c25:dd:dd:dd:ba91
742c19:dd:c25:c25:dd:dd:dd:ba92/1272c19:dd:c25:c25:dd:dd:dd:ba93
752c19:dd:c25:c25:dd:dd:dd:ba94/1272c19:dd:c25:c25:dd:dd:dd:ba95
762c19:dd:c25:c25:dd:dd:dd:ba96/1272c19:dd:c25:c25:dd:dd:dd:ba97
772c19:dd:c25:c25:dd:dd:dd:ba98/1272c19:dd:c25:c25:dd:dd:dd:ba99
782c19:dd:c25:c25:dd:dd:dd:ba9a/1272c19:dd:c25:c25:dd:dd:dd:ba9b
792c19:dd:c25:c25:dd:dd:dd:ba9c/1272c19:dd:c25:c25:dd:dd:dd:ba9d
802c19:dd:c25:c25:dd:dd:dd:ba9e/1272c19:dd:c25:c25:dd:dd:dd:ba9f
812c19:dd:c25:c25:dd:dd:dd:baa0/1272c19:dd:c25:c25:dd:dd:dd:baa1
822c19:dd:c25:c25:dd:dd:dd:baa2/1272c19:dd:c25:c25:dd:dd:dd:baa3
832c19:dd:c25:c25:dd:dd:dd:baa4/1272c19:dd:c25:c25:dd:dd:dd:baa5
842c19:dd:c25:c25:dd:dd:dd:baa6/1272c19:dd:c25:c25:dd:dd:dd:baa7
852c19:dd:c25:c25:dd:dd:dd:baa8/1272c19:dd:c25:c25:dd:dd:dd:baa9
862c19:dd:c25:c25:dd:dd:dd:baaa/1272c19:dd:c25:c25:dd:dd:dd:baab
872c19:dd:c25:c25:dd:dd:dd:baac/1272c19:dd:c25:c25:dd:dd:dd:baad
882c19:dd:c25:c25:dd:dd:dd:baae/1272c19:dd:c25:c25:dd:dd:dd:baaf
892c19:dd:c25:c25:dd:dd:dd:bab0/1272c19:dd:c25:c25:dd:dd:dd:bab1
902c19:dd:c25:c25:dd:dd:dd:bab2/1272c19:dd:c25:c25:dd:dd:dd:bab3
912c19:dd:c25:c25:dd:dd:dd:bab4/1272c19:dd:c25:c25:dd:dd:dd:bab5
922c19:dd:c25:c25:dd:dd:dd:bab6/1272c19:dd:c25:c25:dd:dd:dd:bab7
932c19:dd:c25:c25:dd:dd:dd:bab8/1272c19:dd:c25:c25:dd:dd:dd:bab9
942c19:dd:c25:c25:dd:dd:dd:baba/1272c19:dd:c25:c25:dd:dd:dd:babb
952c19:dd:c25:c25:dd:dd:dd:babc/1272c19:dd:c25:c25:dd:dd:dd:babd
962c19:dd:c25:c25:dd:dd:dd:babe/1272c19:dd:c25:c25:dd:dd:dd:babf
972c19:dd:c25:c25:dd:dd:dd:bac0/1272c19:dd:c25:c25:dd:dd:dd:bac1
982c19:dd:c25:c25:dd:dd:dd:bac2/1272c19:dd:c25:c25:dd:dd:dd:bac3
992c19:dd:c25:c25:dd:dd:dd:bac4/1272c19:dd:c25:c25:dd:dd:dd:bac5
1002c19:dd:c25:c25:dd:dd:dd:bac6/1272c19:dd:c25:c25:dd:dd:dd:bac7
1012c19:dd:c25:c25:dd:dd:dd:bac8/1272c19:dd:c25:c25:dd:dd:dd:bac9
1022c19:dd:c25:c25:dd:dd:dd:baca/1272c19:dd:c25:c25:dd:dd:dd:bacb
1032c19:dd:c25:c25:dd:dd:dd:bacc/1272c19:dd:c25:c25:dd:dd:dd:bacd
1042c19:dd:c25:c25:dd:dd:dd:bace/1272c19:dd:c25:c25:dd:dd:dd:bacf
1052c19:dd:c25:c25:dd:dd:dd:bad0/1272c19:dd:c25:c25:dd:dd:dd:bad1
1062c19:dd:c25:c25:dd:dd:dd:bad2/1272c19:dd:c25:c25:dd:dd:dd:bad3
1072c19:dd:c25:c25:dd:dd:dd:bad4/1272c19:dd:c25:c25:dd:dd:dd:bad5
1082c19:dd:c25:c25:dd:dd:dd:bad6/1272c19:dd:c25:c25:dd:dd:dd:bad7
1092c19:dd:c25:c25:dd:dd:dd:bad8/1272c19:dd:c25:c25:dd:dd:dd:bad9
1102c19:dd:c25:c25:dd:dd:dd:bada/1272c19:dd:c25:c25:dd:dd:dd:badb
1112c19:dd:c25:c25:dd:dd:dd:badc/1272c19:dd:c25:c25:dd:dd:dd:badd
1122c19:dd:c25:c25:dd:dd:dd:bade/1272c19:dd:c25:c25:dd:dd:dd:badf
1132c19:dd:c25:c25:dd:dd:dd:bae0/1272c19:dd:c25:c25:dd:dd:dd:bae1
1142c19:dd:c25:c25:dd:dd:dd:bae2/1272c19:dd:c25:c25:dd:dd:dd:bae3
1152c19:dd:c25:c25:dd:dd:dd:bae4/1272c19:dd:c25:c25:dd:dd:dd:bae5
1162c19:dd:c25:c25:dd:dd:dd:bae6/1272c19:dd:c25:c25:dd:dd:dd:bae7
1172c19:dd:c25:c25:dd:dd:dd:bae8/1272c19:dd:c25:c25:dd:dd:dd:bae9
1182c19:dd:c25:c25:dd:dd:dd:baea/1272c19:dd:c25:c25:dd:dd:dd:baeb
1192c19:dd:c25:c25:dd:dd:dd:baec/1272c19:dd:c25:c25:dd:dd:dd:baed
1202c19:dd:c25:c25:dd:dd:dd:baee/1272c19:dd:c25:c25:dd:dd:dd:baef
1212c19:dd:c25:c25:dd:dd:dd:baf0/1272c19:dd:c25:c25:dd:dd:dd:baf1
1222c19:dd:c25:c25:dd:dd:dd:baf2/1272c19:dd:c25:c25:dd:dd:dd:baf3
1232c19:dd:c25:c25:dd:dd:dd:baf4/1272c19:dd:c25:c25:dd:dd:dd:baf5
1242c19:dd:c25:c25:dd:dd:dd:baf6/1272c19:dd:c25:c25:dd:dd:dd:baf7
1252c19:dd:c25:c25:dd:dd:dd:baf8/1272c19:dd:c25:c25:dd:dd:dd:baf9
1262c19:dd:c25:c25:dd:dd:dd:bafa/1272c19:dd:c25:c25:dd:dd:dd:bafb
1272c19:dd:c25:c25:dd:dd:dd:bafc/1272c19:dd:c25:c25:dd:dd:dd:bafd
1282c19:dd:c25:c25:dd:dd:dd:bafe/1272c19:dd:c25:c25:dd:dd:dd:baff
1292c19:dd:c25:c25:dd:dd:dd:bb00/1272c19:dd:c25:c25:dd:dd:dd:bb01
1302c19:dd:c25:c25:dd:dd:dd:bb02/1272c19:dd:c25:c25:dd:dd:dd:bb03
1312c19:dd:c25:c25:dd:dd:dd:bb04/1272c19:dd:c25:c25:dd:dd:dd:bb05
1322c19:dd:c25:c25:dd:dd:dd:bb06/1272c19:dd:c25:c25:dd:dd:dd:bb07
1332c19:dd:c25:c25:dd:dd:dd:bb08/1272c19:dd:c25:c25:dd:dd:dd:bb09
1342c19:dd:c25:c25:dd:dd:dd:bb0a/1272c19:dd:c25:c25:dd:dd:dd:bb0b
1352c19:dd:c25:c25:dd:dd:dd:bb0c/1272c19:dd:c25:c25:dd:dd:dd:bb0d
1362c19:dd:c25:c25:dd:dd:dd:bb0e/1272c19:dd:c25:c25:dd:dd:dd:bb0f
1372c19:dd:c25:c25:dd:dd:dd:bb10/1272c19:dd:c25:c25:dd:dd:dd:bb11
1382c19:dd:c25:c25:dd:dd:dd:bb12/1272c19:dd:c25:c25:dd:dd:dd:bb13
1392c19:dd:c25:c25:dd:dd:dd:bb14/1272c19:dd:c25:c25:dd:dd:dd:bb15
1402c19:dd:c25:c25:dd:dd:dd:bb16/1272c19:dd:c25:c25:dd:dd:dd:bb17
1412c19:dd:c25:c25:dd:dd:dd:bb18/1272c19:dd:c25:c25:dd:dd:dd:bb19
1422c19:dd:c25:c25:dd:dd:dd:bb1a/1272c19:dd:c25:c25:dd:dd:dd:bb1b
1432c19:dd:c25:c25:dd:dd:dd:bb1c/1272c19:dd:c25:c25:dd:dd:dd:bb1d
1442c19:dd:c25:c25:dd:dd:dd:bb1e/1272c19:dd:c25:c25:dd:dd:dd:bb1f
1452c19:dd:c25:c25:dd:dd:dd:bb20/1272c19:dd:c25:c25:dd:dd:dd:bb21
1462c19:dd:c25:c25:dd:dd:dd:bb22/1272c19:dd:c25:c25:dd:dd:dd:bb23
1472c19:dd:c25:c25:dd:dd:dd:bb24/1272c19:dd:c25:c25:dd:dd:dd:bb25
1482c19:dd:c25:c25:dd:dd:dd:bb26/1272c19:dd:c25:c25:dd:dd:dd:bb27
1492c19:dd:c25:c25:dd:dd:dd:bb28/1272c19:dd:c25:c25:dd:dd:dd:bb29
1502c19:dd:c25:c25:dd:dd:dd:bb2a/1272c19:dd:c25:c25:dd:dd:dd:bb2b
1512c19:dd:c25:c25:dd:dd:dd:bb2c/1272c19:dd:c25:c25:dd:dd:dd:bb2d
1522c19:dd:c25:c25:dd:dd:dd:bb2e/1272c19:dd:c25:c25:dd:dd:dd:bb2f
1532c19:dd:c25:c25:dd:dd:dd:bb30/1272c19:dd:c25:c25:dd:dd:dd:bb31
1542c19:dd:c25:c25:dd:dd:dd:bb32/1272c19:dd:c25:c25:dd:dd:dd:bb33
1552c19:dd:c25:c25:dd:dd:dd:bb34/1272c19:dd:c25:c25:dd:dd:dd:bb35
1562c19:dd:c25:c25:dd:dd:dd:bb36/1272c19:dd:c25:c25:dd:dd:dd:bb37
1572c19:dd:c25:c25:dd:dd:dd:bb38/1272c19:dd:c25:c25:dd:dd:dd:bb39
1582c19:dd:c25:c25:dd:dd:dd:bb3a/1272c19:dd:c25:c25:dd:dd:dd:bb3b
1592c19:dd:c25:c25:dd:dd:dd:bb3c/1272c19:dd:c25:c25:dd:dd:dd:bb3d
1602c19:dd:c25:c25:dd:dd:dd:bb3e/1272c19:dd:c25:c25:dd:dd:dd:bb3f
1612c19:dd:c25:c25:dd:dd:dd:bb40/1272c19:dd:c25:c25:dd:dd:dd:bb41
1622c19:dd:c25:c25:dd:dd:dd:bb42/1272c19:dd:c25:c25:dd:dd:dd:bb43
1632c19:dd:c25:c25:dd:dd:dd:bb44/1272c19:dd:c25:c25:dd:dd:dd:bb45
1642c19:dd:c25:c25:dd:dd:dd:bb46/1272c19:dd:c25:c25:dd:dd:dd:bb47
1652c19:dd:c25:c25:dd:dd:dd:bb48/1272c19:dd:c25:c25:dd:dd:dd:bb49
1662c19:dd:c25:c25:dd:dd:dd:bb4a/1272c19:dd:c25:c25:dd:dd:dd:bb4b
1672c19:dd:c25:c25:dd:dd:dd:bb4c/1272c19:dd:c25:c25:dd:dd:dd:bb4d
1682c19:dd:c25:c25:dd:dd:dd:bb4e/1272c19:dd:c25:c25:dd:dd:dd:bb4f
1692c19:dd:c25:c25:dd:dd:dd:bb50/1272c19:dd:c25:c25:dd:dd:dd:bb51
1702c19:dd:c25:c25:dd:dd:dd:bb52/1272c19:dd:c25:c25:dd:dd:dd:bb53
1712c19:dd:c25:c25:dd:dd:dd:bb54/1272c19:dd:c25:c25:dd:dd:dd:bb55
1722c19:dd:c25:c25:dd:dd:dd:bb56/1272c19:dd:c25:c25:dd:dd:dd:bb57
1732c19:dd:c25:c25:dd:dd:dd:bb58/1272c19:dd:c25:c25:dd:dd:dd:bb59
1742c19:dd:c25:c25:dd:dd:dd:bb5a/1272c19:dd:c25:c25:dd:dd:dd:bb5b
1752c19:dd:c25:c25:dd:dd:dd:bb5c/1272c19:dd:c25:c25:dd:dd:dd:bb5d
1762c19:dd:c25:c25:dd:dd:dd:bb5e/1272c19:dd:c25:c25:dd:dd:dd:bb5f
1772c19:dd:c25:c25:dd:dd:dd:bb60/1272c19:dd:c25:c25:dd:dd:dd:bb61
1782c19:dd:c25:c25:dd:dd:dd:bb62/1272c19:dd:c25:c25:dd:dd:dd:bb63
1792c19:dd:c25:c25:dd:dd:dd:bb64/1272c19:dd:c25:c25:dd:dd:dd:bb65
1802c19:dd:c25:c25:dd:dd:dd:bb66/1272c19:dd:c25:c25:dd:dd:dd:bb67
1812c19:dd:c25:c25:dd:dd:dd:bb68/1272c19:dd:c25:c25:dd:dd:dd:bb69
1822c19:dd:c25:c25:dd:dd:dd:bb6a/1272c19:dd:c25:c25:dd:dd:dd:bb6b
1832c19:dd:c25:c25:dd:dd:dd:bb6c/1272c19:dd:c25:c25:dd:dd:dd:bb6d
1842c19:dd:c25:c25:dd:dd:dd:bb6e/1272c19:dd:c25:c25:dd:dd:dd:bb6f
1852c19:dd:c25:c25:dd:dd:dd:bb70/1272c19:dd:c25:c25:dd:dd:dd:bb71
1862c19:dd:c25:c25:dd:dd:dd:bb72/1272c19:dd:c25:c25:dd:dd:dd:bb73
1872c19:dd:c25:c25:dd:dd:dd:bb74/1272c19:dd:c25:c25:dd:dd:dd:bb75
1882c19:dd:c25:c25:dd:dd:dd:bb76/1272c19:dd:c25:c25:dd:dd:dd:bb77
1892c19:dd:c25:c25:dd:dd:dd:bb78/1272c19:dd:c25:c25:dd:dd:dd:bb79
1902c19:dd:c25:c25:dd:dd:dd:bb7a/1272c19:dd:c25:c25:dd:dd:dd:bb7b
1912c19:dd:c25:c25:dd:dd:dd:bb7c/1272c19:dd:c25:c25:dd:dd:dd:bb7d
1922c19:dd:c25:c25:dd:dd:dd:bb7e/1272c19:dd:c25:c25:dd:dd:dd:bb7f
1932c19:dd:c25:c25:dd:dd:dd:bb80/1272c19:dd:c25:c25:dd:dd:dd:bb81
1942c19:dd:c25:c25:dd:dd:dd:bb82/1272c19:dd:c25:c25:dd:dd:dd:bb83
1952c19:dd:c25:c25:dd:dd:dd:bb84/1272c19:dd:c25:c25:dd:dd:dd:bb85
1962c19:dd:c25:c25:dd:dd:dd:bb86/1272c19:dd:c25:c25:dd:dd:dd:bb87
1972c19:dd:c25:c25:dd:dd:dd:bb88/1272c19:dd:c25:c25:dd:dd:dd:bb89
1982c19:dd:c25:c25:dd:dd:dd:bb8a/1272c19:dd:c25:c25:dd:dd:dd:bb8b
1992c19:dd:c25:c25:dd:dd:dd:bb8c/1272c19:dd:c25:c25:dd:dd:dd:bb8d
2002c19:dd:c25:c25:dd:dd:dd:bb8e/1272c19:dd:c25:c25:dd:dd:dd:bb8f
2012c19:dd:c25:c25:dd:dd:dd:bb90/1272c19:dd:c25:c25:dd:dd:dd:bb91
2022c19:dd:c25:c25:dd:dd:dd:bb92/1272c19:dd:c25:c25:dd:dd:dd:bb93
2032c19:dd:c25:c25:dd:dd:dd:bb94/1272c19:dd:c25:c25:dd:dd:dd:bb95
2042c19:dd:c25:c25:dd:dd:dd:bb96/1272c19:dd:c25:c25:dd:dd:dd:bb97
2052c19:dd:c25:c25:dd:dd:dd:bb98/1272c19:dd:c25:c25:dd:dd:dd:bb99
2062c19:dd:c25:c25:dd:dd:dd:bb9a/1272c19:dd:c25:c25:dd:dd:dd:bb9b
2072c19:dd:c25:c25:dd:dd:dd:bb9c/1272c19:dd:c25:c25:dd:dd:dd:bb9d
2082c19:dd:c25:c25:dd:dd:dd:bb9e/1272c19:dd:c25:c25:dd:dd:dd:bb9f
2092c19:dd:c25:c25:dd:dd:dd:bba0/1272c19:dd:c25:c25:dd:dd:dd:bba1
2102c19:dd:c25:c25:dd:dd:dd:bba2/1272c19:dd:c25:c25:dd:dd:dd:bba3
2112c19:dd:c25:c25:dd:dd:dd:bba4/1272c19:dd:c25:c25:dd:dd:dd:bba5
2122c19:dd:c25:c25:dd:dd:dd:bba6/1272c19:dd:c25:c25:dd:dd:dd:bba7
2132c19:dd:c25:c25:dd:dd:dd:bba8/1272c19:dd:c25:c25:dd:dd:dd:bba9
2142c19:dd:c25:c25:dd:dd:dd:bbaa/1272c19:dd:c25:c25:dd:dd:dd:bbab
2152c19:dd:c25:c25:dd:dd:dd:bbac/1272c19:dd:c25:c25:dd:dd:dd:bbad
2162c19:dd:c25:c25:dd:dd:dd:bbae/1272c19:dd:c25:c25:dd:dd:dd:bbaf
2172c19:dd:c25:c25:dd:dd:dd:bbb0/1272c19:dd:c25:c25:dd:dd:dd:bbb1
2182c19:dd:c25:c25:dd:dd:dd:bbb2/1272c19:dd:c25:c25:dd:dd:dd:bbb3
2192c19:dd:c25:c25:dd:dd:dd:bbb4/1272c19:dd:c25:c25:dd:dd:dd:bbb5
2202c19:dd:c25:c25:dd:dd:dd:bbb6/1272c19:dd:c25:c25:dd:dd:dd:bbb7
2212c19:dd:c25:c25:dd:dd:dd:bbb8/1272c19:dd:c25:c25:dd:dd:dd:bbb9
2222c19:dd:c25:c25:dd:dd:dd:bbba/1272c19:dd:c25:c25:dd:dd:dd:bbbb
2232c19:dd:c25:c25:dd:dd:dd:bbbc/1272c19:dd:c25:c25:dd:dd:dd:bbbd
2242c19:dd:c25:c25:dd:dd:dd:bbbe/1272c19:dd:c25:c25:dd:dd:dd:bbbf
2252c19:dd:c25:c25:dd:dd:dd:bbc0/1272c19:dd:c25:c25:dd:dd:dd:bbc1
2262c19:dd:c25:c25:dd:dd:dd:bbc2/1272c19:dd:c25:c25:dd:dd:dd:bbc3
2272c19:dd:c25:c25:dd:dd:dd:bbc4/1272c19:dd:c25:c25:dd:dd:dd:bbc5
2282c19:dd:c25:c25:dd:dd:dd:bbc6/1272c19:dd:c25:c25:dd:dd:dd:bbc7
2292c19:dd:c25:c25:dd:dd:dd:bbc8/1272c19:dd:c25:c25:dd:dd:dd:bbc9
2302c19:dd:c25:c25:dd:dd:dd:bbca/1272c19:dd:c25:c25:dd:dd:dd:bbcb
2312c19:dd:c25:c25:dd:dd:dd:bbcc/1272c19:dd:c25:c25:dd:dd:dd:bbcd
2322c19:dd:c25:c25:dd:dd:dd:bbce/1272c19:dd:c25:c25:dd:dd:dd:bbcf
2332c19:dd:c25:c25:dd:dd:dd:bbd0/1272c19:dd:c25:c25:dd:dd:dd:bbd1
2342c19:dd:c25:c25:dd:dd:dd:bbd2/1272c19:dd:c25:c25:dd:dd:dd:bbd3
2352c19:dd:c25:c25:dd:dd:dd:bbd4/1272c19:dd:c25:c25:dd:dd:dd:bbd5
2362c19:dd:c25:c25:dd:dd:dd:bbd6/1272c19:dd:c25:c25:dd:dd:dd:bbd7
2372c19:dd:c25:c25:dd:dd:dd:bbd8/1272c19:dd:c25:c25:dd:dd:dd:bbd9
2382c19:dd:c25:c25:dd:dd:dd:bbda/1272c19:dd:c25:c25:dd:dd:dd:bbdb
2392c19:dd:c25:c25:dd:dd:dd:bbdc/1272c19:dd:c25:c25:dd:dd:dd:bbdd
2402c19:dd:c25:c25:dd:dd:dd:bbde/1272c19:dd:c25:c25:dd:dd:dd:bbdf
2412c19:dd:c25:c25:dd:dd:dd:bbe0/1272c19:dd:c25:c25:dd:dd:dd:bbe1
2422c19:dd:c25:c25:dd:dd:dd:bbe2/1272c19:dd:c25:c25:dd:dd:dd:bbe3
2432c19:dd:c25:c25:dd:dd:dd:bbe4/1272c19:dd:c25:c25:dd:dd:dd:bbe5
2442c19:dd:c25:c25:dd:dd:dd:bbe6/1272c19:dd:c25:c25:dd:dd:dd:bbe7
2452c19:dd:c25:c25:dd:dd:dd:bbe8/1272c19:dd:c25:c25:dd:dd:dd:bbe9
2462c19:dd:c25:c25:dd:dd:dd:bbea/1272c19:dd:c25:c25:dd:dd:dd:bbeb
2472c19:dd:c25:c25:dd:dd:dd:bbec/1272c19:dd:c25:c25:dd:dd:dd:bbed
2482c19:dd:c25:c25:dd:dd:dd:bbee/1272c19:dd:c25:c25:dd:dd:dd:bbef
2492c19:dd:c25:c25:dd:dd:dd:bbf0/1272c19:dd:c25:c25:dd:dd:dd:bbf1
2502c19:dd:c25:c25:dd:dd:dd:bbf2/1272c19:dd:c25:c25:dd:dd:dd:bbf3
2512c19:dd:c25:c25:dd:dd:dd:bbf4/1272c19:dd:c25:c25:dd:dd:dd:bbf5
2522c19:dd:c25:c25:dd:dd:dd:bbf6/1272c19:dd:c25:c25:dd:dd:dd:bbf7
2532c19:dd:c25:c25:dd:dd:dd:bbf8/1272c19:dd:c25:c25:dd:dd:dd:bbf9
2542c19:dd:c25:c25:dd:dd:dd:bbfa/1272c19:dd:c25:c25:dd:dd:dd:bbfb
2552c19:dd:c25:c25:dd:dd:dd:bbfc/1272c19:dd:c25:c25:dd:dd:dd:bbfd
2562c19:dd:c25:c25:dd:dd:dd:bbfe/1272c19:dd:c25:c25:dd:dd:dd:bbff

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.