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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:ac00/119
First address
2c19:dd:c25:c25:dd:dd:dd:ac00
Last address
2c19:dd:c25:c25:dd:dd:dd:adff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:0c25:00dd:00dd:00dd:ac00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
c.a.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
d.a.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:ac00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:c25:c25:dd:dd:dd:ac00/1272c19:dd:c25:c25:dd:dd:dd:ac01
22c19:dd:c25:c25:dd:dd:dd:ac02/1272c19:dd:c25:c25:dd:dd:dd:ac03
32c19:dd:c25:c25:dd:dd:dd:ac04/1272c19:dd:c25:c25:dd:dd:dd:ac05
42c19:dd:c25:c25:dd:dd:dd:ac06/1272c19:dd:c25:c25:dd:dd:dd:ac07
52c19:dd:c25:c25:dd:dd:dd:ac08/1272c19:dd:c25:c25:dd:dd:dd:ac09
62c19:dd:c25:c25:dd:dd:dd:ac0a/1272c19:dd:c25:c25:dd:dd:dd:ac0b
72c19:dd:c25:c25:dd:dd:dd:ac0c/1272c19:dd:c25:c25:dd:dd:dd:ac0d
82c19:dd:c25:c25:dd:dd:dd:ac0e/1272c19:dd:c25:c25:dd:dd:dd:ac0f
92c19:dd:c25:c25:dd:dd:dd:ac10/1272c19:dd:c25:c25:dd:dd:dd:ac11
102c19:dd:c25:c25:dd:dd:dd:ac12/1272c19:dd:c25:c25:dd:dd:dd:ac13
112c19:dd:c25:c25:dd:dd:dd:ac14/1272c19:dd:c25:c25:dd:dd:dd:ac15
122c19:dd:c25:c25:dd:dd:dd:ac16/1272c19:dd:c25:c25:dd:dd:dd:ac17
132c19:dd:c25:c25:dd:dd:dd:ac18/1272c19:dd:c25:c25:dd:dd:dd:ac19
142c19:dd:c25:c25:dd:dd:dd:ac1a/1272c19:dd:c25:c25:dd:dd:dd:ac1b
152c19:dd:c25:c25:dd:dd:dd:ac1c/1272c19:dd:c25:c25:dd:dd:dd:ac1d
162c19:dd:c25:c25:dd:dd:dd:ac1e/1272c19:dd:c25:c25:dd:dd:dd:ac1f
172c19:dd:c25:c25:dd:dd:dd:ac20/1272c19:dd:c25:c25:dd:dd:dd:ac21
182c19:dd:c25:c25:dd:dd:dd:ac22/1272c19:dd:c25:c25:dd:dd:dd:ac23
192c19:dd:c25:c25:dd:dd:dd:ac24/1272c19:dd:c25:c25:dd:dd:dd:ac25
202c19:dd:c25:c25:dd:dd:dd:ac26/1272c19:dd:c25:c25:dd:dd:dd:ac27
212c19:dd:c25:c25:dd:dd:dd:ac28/1272c19:dd:c25:c25:dd:dd:dd:ac29
222c19:dd:c25:c25:dd:dd:dd:ac2a/1272c19:dd:c25:c25:dd:dd:dd:ac2b
232c19:dd:c25:c25:dd:dd:dd:ac2c/1272c19:dd:c25:c25:dd:dd:dd:ac2d
242c19:dd:c25:c25:dd:dd:dd:ac2e/1272c19:dd:c25:c25:dd:dd:dd:ac2f
252c19:dd:c25:c25:dd:dd:dd:ac30/1272c19:dd:c25:c25:dd:dd:dd:ac31
262c19:dd:c25:c25:dd:dd:dd:ac32/1272c19:dd:c25:c25:dd:dd:dd:ac33
272c19:dd:c25:c25:dd:dd:dd:ac34/1272c19:dd:c25:c25:dd:dd:dd:ac35
282c19:dd:c25:c25:dd:dd:dd:ac36/1272c19:dd:c25:c25:dd:dd:dd:ac37
292c19:dd:c25:c25:dd:dd:dd:ac38/1272c19:dd:c25:c25:dd:dd:dd:ac39
302c19:dd:c25:c25:dd:dd:dd:ac3a/1272c19:dd:c25:c25:dd:dd:dd:ac3b
312c19:dd:c25:c25:dd:dd:dd:ac3c/1272c19:dd:c25:c25:dd:dd:dd:ac3d
322c19:dd:c25:c25:dd:dd:dd:ac3e/1272c19:dd:c25:c25:dd:dd:dd:ac3f
332c19:dd:c25:c25:dd:dd:dd:ac40/1272c19:dd:c25:c25:dd:dd:dd:ac41
342c19:dd:c25:c25:dd:dd:dd:ac42/1272c19:dd:c25:c25:dd:dd:dd:ac43
352c19:dd:c25:c25:dd:dd:dd:ac44/1272c19:dd:c25:c25:dd:dd:dd:ac45
362c19:dd:c25:c25:dd:dd:dd:ac46/1272c19:dd:c25:c25:dd:dd:dd:ac47
372c19:dd:c25:c25:dd:dd:dd:ac48/1272c19:dd:c25:c25:dd:dd:dd:ac49
382c19:dd:c25:c25:dd:dd:dd:ac4a/1272c19:dd:c25:c25:dd:dd:dd:ac4b
392c19:dd:c25:c25:dd:dd:dd:ac4c/1272c19:dd:c25:c25:dd:dd:dd:ac4d
402c19:dd:c25:c25:dd:dd:dd:ac4e/1272c19:dd:c25:c25:dd:dd:dd:ac4f
412c19:dd:c25:c25:dd:dd:dd:ac50/1272c19:dd:c25:c25:dd:dd:dd:ac51
422c19:dd:c25:c25:dd:dd:dd:ac52/1272c19:dd:c25:c25:dd:dd:dd:ac53
432c19:dd:c25:c25:dd:dd:dd:ac54/1272c19:dd:c25:c25:dd:dd:dd:ac55
442c19:dd:c25:c25:dd:dd:dd:ac56/1272c19:dd:c25:c25:dd:dd:dd:ac57
452c19:dd:c25:c25:dd:dd:dd:ac58/1272c19:dd:c25:c25:dd:dd:dd:ac59
462c19:dd:c25:c25:dd:dd:dd:ac5a/1272c19:dd:c25:c25:dd:dd:dd:ac5b
472c19:dd:c25:c25:dd:dd:dd:ac5c/1272c19:dd:c25:c25:dd:dd:dd:ac5d
482c19:dd:c25:c25:dd:dd:dd:ac5e/1272c19:dd:c25:c25:dd:dd:dd:ac5f
492c19:dd:c25:c25:dd:dd:dd:ac60/1272c19:dd:c25:c25:dd:dd:dd:ac61
502c19:dd:c25:c25:dd:dd:dd:ac62/1272c19:dd:c25:c25:dd:dd:dd:ac63
512c19:dd:c25:c25:dd:dd:dd:ac64/1272c19:dd:c25:c25:dd:dd:dd:ac65
522c19:dd:c25:c25:dd:dd:dd:ac66/1272c19:dd:c25:c25:dd:dd:dd:ac67
532c19:dd:c25:c25:dd:dd:dd:ac68/1272c19:dd:c25:c25:dd:dd:dd:ac69
542c19:dd:c25:c25:dd:dd:dd:ac6a/1272c19:dd:c25:c25:dd:dd:dd:ac6b
552c19:dd:c25:c25:dd:dd:dd:ac6c/1272c19:dd:c25:c25:dd:dd:dd:ac6d
562c19:dd:c25:c25:dd:dd:dd:ac6e/1272c19:dd:c25:c25:dd:dd:dd:ac6f
572c19:dd:c25:c25:dd:dd:dd:ac70/1272c19:dd:c25:c25:dd:dd:dd:ac71
582c19:dd:c25:c25:dd:dd:dd:ac72/1272c19:dd:c25:c25:dd:dd:dd:ac73
592c19:dd:c25:c25:dd:dd:dd:ac74/1272c19:dd:c25:c25:dd:dd:dd:ac75
602c19:dd:c25:c25:dd:dd:dd:ac76/1272c19:dd:c25:c25:dd:dd:dd:ac77
612c19:dd:c25:c25:dd:dd:dd:ac78/1272c19:dd:c25:c25:dd:dd:dd:ac79
622c19:dd:c25:c25:dd:dd:dd:ac7a/1272c19:dd:c25:c25:dd:dd:dd:ac7b
632c19:dd:c25:c25:dd:dd:dd:ac7c/1272c19:dd:c25:c25:dd:dd:dd:ac7d
642c19:dd:c25:c25:dd:dd:dd:ac7e/1272c19:dd:c25:c25:dd:dd:dd:ac7f
652c19:dd:c25:c25:dd:dd:dd:ac80/1272c19:dd:c25:c25:dd:dd:dd:ac81
662c19:dd:c25:c25:dd:dd:dd:ac82/1272c19:dd:c25:c25:dd:dd:dd:ac83
672c19:dd:c25:c25:dd:dd:dd:ac84/1272c19:dd:c25:c25:dd:dd:dd:ac85
682c19:dd:c25:c25:dd:dd:dd:ac86/1272c19:dd:c25:c25:dd:dd:dd:ac87
692c19:dd:c25:c25:dd:dd:dd:ac88/1272c19:dd:c25:c25:dd:dd:dd:ac89
702c19:dd:c25:c25:dd:dd:dd:ac8a/1272c19:dd:c25:c25:dd:dd:dd:ac8b
712c19:dd:c25:c25:dd:dd:dd:ac8c/1272c19:dd:c25:c25:dd:dd:dd:ac8d
722c19:dd:c25:c25:dd:dd:dd:ac8e/1272c19:dd:c25:c25:dd:dd:dd:ac8f
732c19:dd:c25:c25:dd:dd:dd:ac90/1272c19:dd:c25:c25:dd:dd:dd:ac91
742c19:dd:c25:c25:dd:dd:dd:ac92/1272c19:dd:c25:c25:dd:dd:dd:ac93
752c19:dd:c25:c25:dd:dd:dd:ac94/1272c19:dd:c25:c25:dd:dd:dd:ac95
762c19:dd:c25:c25:dd:dd:dd:ac96/1272c19:dd:c25:c25:dd:dd:dd:ac97
772c19:dd:c25:c25:dd:dd:dd:ac98/1272c19:dd:c25:c25:dd:dd:dd:ac99
782c19:dd:c25:c25:dd:dd:dd:ac9a/1272c19:dd:c25:c25:dd:dd:dd:ac9b
792c19:dd:c25:c25:dd:dd:dd:ac9c/1272c19:dd:c25:c25:dd:dd:dd:ac9d
802c19:dd:c25:c25:dd:dd:dd:ac9e/1272c19:dd:c25:c25:dd:dd:dd:ac9f
812c19:dd:c25:c25:dd:dd:dd:aca0/1272c19:dd:c25:c25:dd:dd:dd:aca1
822c19:dd:c25:c25:dd:dd:dd:aca2/1272c19:dd:c25:c25:dd:dd:dd:aca3
832c19:dd:c25:c25:dd:dd:dd:aca4/1272c19:dd:c25:c25:dd:dd:dd:aca5
842c19:dd:c25:c25:dd:dd:dd:aca6/1272c19:dd:c25:c25:dd:dd:dd:aca7
852c19:dd:c25:c25:dd:dd:dd:aca8/1272c19:dd:c25:c25:dd:dd:dd:aca9
862c19:dd:c25:c25:dd:dd:dd:acaa/1272c19:dd:c25:c25:dd:dd:dd:acab
872c19:dd:c25:c25:dd:dd:dd:acac/1272c19:dd:c25:c25:dd:dd:dd:acad
882c19:dd:c25:c25:dd:dd:dd:acae/1272c19:dd:c25:c25:dd:dd:dd:acaf
892c19:dd:c25:c25:dd:dd:dd:acb0/1272c19:dd:c25:c25:dd:dd:dd:acb1
902c19:dd:c25:c25:dd:dd:dd:acb2/1272c19:dd:c25:c25:dd:dd:dd:acb3
912c19:dd:c25:c25:dd:dd:dd:acb4/1272c19:dd:c25:c25:dd:dd:dd:acb5
922c19:dd:c25:c25:dd:dd:dd:acb6/1272c19:dd:c25:c25:dd:dd:dd:acb7
932c19:dd:c25:c25:dd:dd:dd:acb8/1272c19:dd:c25:c25:dd:dd:dd:acb9
942c19:dd:c25:c25:dd:dd:dd:acba/1272c19:dd:c25:c25:dd:dd:dd:acbb
952c19:dd:c25:c25:dd:dd:dd:acbc/1272c19:dd:c25:c25:dd:dd:dd:acbd
962c19:dd:c25:c25:dd:dd:dd:acbe/1272c19:dd:c25:c25:dd:dd:dd:acbf
972c19:dd:c25:c25:dd:dd:dd:acc0/1272c19:dd:c25:c25:dd:dd:dd:acc1
982c19:dd:c25:c25:dd:dd:dd:acc2/1272c19:dd:c25:c25:dd:dd:dd:acc3
992c19:dd:c25:c25:dd:dd:dd:acc4/1272c19:dd:c25:c25:dd:dd:dd:acc5
1002c19:dd:c25:c25:dd:dd:dd:acc6/1272c19:dd:c25:c25:dd:dd:dd:acc7
1012c19:dd:c25:c25:dd:dd:dd:acc8/1272c19:dd:c25:c25:dd:dd:dd:acc9
1022c19:dd:c25:c25:dd:dd:dd:acca/1272c19:dd:c25:c25:dd:dd:dd:accb
1032c19:dd:c25:c25:dd:dd:dd:accc/1272c19:dd:c25:c25:dd:dd:dd:accd
1042c19:dd:c25:c25:dd:dd:dd:acce/1272c19:dd:c25:c25:dd:dd:dd:accf
1052c19:dd:c25:c25:dd:dd:dd:acd0/1272c19:dd:c25:c25:dd:dd:dd:acd1
1062c19:dd:c25:c25:dd:dd:dd:acd2/1272c19:dd:c25:c25:dd:dd:dd:acd3
1072c19:dd:c25:c25:dd:dd:dd:acd4/1272c19:dd:c25:c25:dd:dd:dd:acd5
1082c19:dd:c25:c25:dd:dd:dd:acd6/1272c19:dd:c25:c25:dd:dd:dd:acd7
1092c19:dd:c25:c25:dd:dd:dd:acd8/1272c19:dd:c25:c25:dd:dd:dd:acd9
1102c19:dd:c25:c25:dd:dd:dd:acda/1272c19:dd:c25:c25:dd:dd:dd:acdb
1112c19:dd:c25:c25:dd:dd:dd:acdc/1272c19:dd:c25:c25:dd:dd:dd:acdd
1122c19:dd:c25:c25:dd:dd:dd:acde/1272c19:dd:c25:c25:dd:dd:dd:acdf
1132c19:dd:c25:c25:dd:dd:dd:ace0/1272c19:dd:c25:c25:dd:dd:dd:ace1
1142c19:dd:c25:c25:dd:dd:dd:ace2/1272c19:dd:c25:c25:dd:dd:dd:ace3
1152c19:dd:c25:c25:dd:dd:dd:ace4/1272c19:dd:c25:c25:dd:dd:dd:ace5
1162c19:dd:c25:c25:dd:dd:dd:ace6/1272c19:dd:c25:c25:dd:dd:dd:ace7
1172c19:dd:c25:c25:dd:dd:dd:ace8/1272c19:dd:c25:c25:dd:dd:dd:ace9
1182c19:dd:c25:c25:dd:dd:dd:acea/1272c19:dd:c25:c25:dd:dd:dd:aceb
1192c19:dd:c25:c25:dd:dd:dd:acec/1272c19:dd:c25:c25:dd:dd:dd:aced
1202c19:dd:c25:c25:dd:dd:dd:acee/1272c19:dd:c25:c25:dd:dd:dd:acef
1212c19:dd:c25:c25:dd:dd:dd:acf0/1272c19:dd:c25:c25:dd:dd:dd:acf1
1222c19:dd:c25:c25:dd:dd:dd:acf2/1272c19:dd:c25:c25:dd:dd:dd:acf3
1232c19:dd:c25:c25:dd:dd:dd:acf4/1272c19:dd:c25:c25:dd:dd:dd:acf5
1242c19:dd:c25:c25:dd:dd:dd:acf6/1272c19:dd:c25:c25:dd:dd:dd:acf7
1252c19:dd:c25:c25:dd:dd:dd:acf8/1272c19:dd:c25:c25:dd:dd:dd:acf9
1262c19:dd:c25:c25:dd:dd:dd:acfa/1272c19:dd:c25:c25:dd:dd:dd:acfb
1272c19:dd:c25:c25:dd:dd:dd:acfc/1272c19:dd:c25:c25:dd:dd:dd:acfd
1282c19:dd:c25:c25:dd:dd:dd:acfe/1272c19:dd:c25:c25:dd:dd:dd:acff
1292c19:dd:c25:c25:dd:dd:dd:ad00/1272c19:dd:c25:c25:dd:dd:dd:ad01
1302c19:dd:c25:c25:dd:dd:dd:ad02/1272c19:dd:c25:c25:dd:dd:dd:ad03
1312c19:dd:c25:c25:dd:dd:dd:ad04/1272c19:dd:c25:c25:dd:dd:dd:ad05
1322c19:dd:c25:c25:dd:dd:dd:ad06/1272c19:dd:c25:c25:dd:dd:dd:ad07
1332c19:dd:c25:c25:dd:dd:dd:ad08/1272c19:dd:c25:c25:dd:dd:dd:ad09
1342c19:dd:c25:c25:dd:dd:dd:ad0a/1272c19:dd:c25:c25:dd:dd:dd:ad0b
1352c19:dd:c25:c25:dd:dd:dd:ad0c/1272c19:dd:c25:c25:dd:dd:dd:ad0d
1362c19:dd:c25:c25:dd:dd:dd:ad0e/1272c19:dd:c25:c25:dd:dd:dd:ad0f
1372c19:dd:c25:c25:dd:dd:dd:ad10/1272c19:dd:c25:c25:dd:dd:dd:ad11
1382c19:dd:c25:c25:dd:dd:dd:ad12/1272c19:dd:c25:c25:dd:dd:dd:ad13
1392c19:dd:c25:c25:dd:dd:dd:ad14/1272c19:dd:c25:c25:dd:dd:dd:ad15
1402c19:dd:c25:c25:dd:dd:dd:ad16/1272c19:dd:c25:c25:dd:dd:dd:ad17
1412c19:dd:c25:c25:dd:dd:dd:ad18/1272c19:dd:c25:c25:dd:dd:dd:ad19
1422c19:dd:c25:c25:dd:dd:dd:ad1a/1272c19:dd:c25:c25:dd:dd:dd:ad1b
1432c19:dd:c25:c25:dd:dd:dd:ad1c/1272c19:dd:c25:c25:dd:dd:dd:ad1d
1442c19:dd:c25:c25:dd:dd:dd:ad1e/1272c19:dd:c25:c25:dd:dd:dd:ad1f
1452c19:dd:c25:c25:dd:dd:dd:ad20/1272c19:dd:c25:c25:dd:dd:dd:ad21
1462c19:dd:c25:c25:dd:dd:dd:ad22/1272c19:dd:c25:c25:dd:dd:dd:ad23
1472c19:dd:c25:c25:dd:dd:dd:ad24/1272c19:dd:c25:c25:dd:dd:dd:ad25
1482c19:dd:c25:c25:dd:dd:dd:ad26/1272c19:dd:c25:c25:dd:dd:dd:ad27
1492c19:dd:c25:c25:dd:dd:dd:ad28/1272c19:dd:c25:c25:dd:dd:dd:ad29
1502c19:dd:c25:c25:dd:dd:dd:ad2a/1272c19:dd:c25:c25:dd:dd:dd:ad2b
1512c19:dd:c25:c25:dd:dd:dd:ad2c/1272c19:dd:c25:c25:dd:dd:dd:ad2d
1522c19:dd:c25:c25:dd:dd:dd:ad2e/1272c19:dd:c25:c25:dd:dd:dd:ad2f
1532c19:dd:c25:c25:dd:dd:dd:ad30/1272c19:dd:c25:c25:dd:dd:dd:ad31
1542c19:dd:c25:c25:dd:dd:dd:ad32/1272c19:dd:c25:c25:dd:dd:dd:ad33
1552c19:dd:c25:c25:dd:dd:dd:ad34/1272c19:dd:c25:c25:dd:dd:dd:ad35
1562c19:dd:c25:c25:dd:dd:dd:ad36/1272c19:dd:c25:c25:dd:dd:dd:ad37
1572c19:dd:c25:c25:dd:dd:dd:ad38/1272c19:dd:c25:c25:dd:dd:dd:ad39
1582c19:dd:c25:c25:dd:dd:dd:ad3a/1272c19:dd:c25:c25:dd:dd:dd:ad3b
1592c19:dd:c25:c25:dd:dd:dd:ad3c/1272c19:dd:c25:c25:dd:dd:dd:ad3d
1602c19:dd:c25:c25:dd:dd:dd:ad3e/1272c19:dd:c25:c25:dd:dd:dd:ad3f
1612c19:dd:c25:c25:dd:dd:dd:ad40/1272c19:dd:c25:c25:dd:dd:dd:ad41
1622c19:dd:c25:c25:dd:dd:dd:ad42/1272c19:dd:c25:c25:dd:dd:dd:ad43
1632c19:dd:c25:c25:dd:dd:dd:ad44/1272c19:dd:c25:c25:dd:dd:dd:ad45
1642c19:dd:c25:c25:dd:dd:dd:ad46/1272c19:dd:c25:c25:dd:dd:dd:ad47
1652c19:dd:c25:c25:dd:dd:dd:ad48/1272c19:dd:c25:c25:dd:dd:dd:ad49
1662c19:dd:c25:c25:dd:dd:dd:ad4a/1272c19:dd:c25:c25:dd:dd:dd:ad4b
1672c19:dd:c25:c25:dd:dd:dd:ad4c/1272c19:dd:c25:c25:dd:dd:dd:ad4d
1682c19:dd:c25:c25:dd:dd:dd:ad4e/1272c19:dd:c25:c25:dd:dd:dd:ad4f
1692c19:dd:c25:c25:dd:dd:dd:ad50/1272c19:dd:c25:c25:dd:dd:dd:ad51
1702c19:dd:c25:c25:dd:dd:dd:ad52/1272c19:dd:c25:c25:dd:dd:dd:ad53
1712c19:dd:c25:c25:dd:dd:dd:ad54/1272c19:dd:c25:c25:dd:dd:dd:ad55
1722c19:dd:c25:c25:dd:dd:dd:ad56/1272c19:dd:c25:c25:dd:dd:dd:ad57
1732c19:dd:c25:c25:dd:dd:dd:ad58/1272c19:dd:c25:c25:dd:dd:dd:ad59
1742c19:dd:c25:c25:dd:dd:dd:ad5a/1272c19:dd:c25:c25:dd:dd:dd:ad5b
1752c19:dd:c25:c25:dd:dd:dd:ad5c/1272c19:dd:c25:c25:dd:dd:dd:ad5d
1762c19:dd:c25:c25:dd:dd:dd:ad5e/1272c19:dd:c25:c25:dd:dd:dd:ad5f
1772c19:dd:c25:c25:dd:dd:dd:ad60/1272c19:dd:c25:c25:dd:dd:dd:ad61
1782c19:dd:c25:c25:dd:dd:dd:ad62/1272c19:dd:c25:c25:dd:dd:dd:ad63
1792c19:dd:c25:c25:dd:dd:dd:ad64/1272c19:dd:c25:c25:dd:dd:dd:ad65
1802c19:dd:c25:c25:dd:dd:dd:ad66/1272c19:dd:c25:c25:dd:dd:dd:ad67
1812c19:dd:c25:c25:dd:dd:dd:ad68/1272c19:dd:c25:c25:dd:dd:dd:ad69
1822c19:dd:c25:c25:dd:dd:dd:ad6a/1272c19:dd:c25:c25:dd:dd:dd:ad6b
1832c19:dd:c25:c25:dd:dd:dd:ad6c/1272c19:dd:c25:c25:dd:dd:dd:ad6d
1842c19:dd:c25:c25:dd:dd:dd:ad6e/1272c19:dd:c25:c25:dd:dd:dd:ad6f
1852c19:dd:c25:c25:dd:dd:dd:ad70/1272c19:dd:c25:c25:dd:dd:dd:ad71
1862c19:dd:c25:c25:dd:dd:dd:ad72/1272c19:dd:c25:c25:dd:dd:dd:ad73
1872c19:dd:c25:c25:dd:dd:dd:ad74/1272c19:dd:c25:c25:dd:dd:dd:ad75
1882c19:dd:c25:c25:dd:dd:dd:ad76/1272c19:dd:c25:c25:dd:dd:dd:ad77
1892c19:dd:c25:c25:dd:dd:dd:ad78/1272c19:dd:c25:c25:dd:dd:dd:ad79
1902c19:dd:c25:c25:dd:dd:dd:ad7a/1272c19:dd:c25:c25:dd:dd:dd:ad7b
1912c19:dd:c25:c25:dd:dd:dd:ad7c/1272c19:dd:c25:c25:dd:dd:dd:ad7d
1922c19:dd:c25:c25:dd:dd:dd:ad7e/1272c19:dd:c25:c25:dd:dd:dd:ad7f
1932c19:dd:c25:c25:dd:dd:dd:ad80/1272c19:dd:c25:c25:dd:dd:dd:ad81
1942c19:dd:c25:c25:dd:dd:dd:ad82/1272c19:dd:c25:c25:dd:dd:dd:ad83
1952c19:dd:c25:c25:dd:dd:dd:ad84/1272c19:dd:c25:c25:dd:dd:dd:ad85
1962c19:dd:c25:c25:dd:dd:dd:ad86/1272c19:dd:c25:c25:dd:dd:dd:ad87
1972c19:dd:c25:c25:dd:dd:dd:ad88/1272c19:dd:c25:c25:dd:dd:dd:ad89
1982c19:dd:c25:c25:dd:dd:dd:ad8a/1272c19:dd:c25:c25:dd:dd:dd:ad8b
1992c19:dd:c25:c25:dd:dd:dd:ad8c/1272c19:dd:c25:c25:dd:dd:dd:ad8d
2002c19:dd:c25:c25:dd:dd:dd:ad8e/1272c19:dd:c25:c25:dd:dd:dd:ad8f
2012c19:dd:c25:c25:dd:dd:dd:ad90/1272c19:dd:c25:c25:dd:dd:dd:ad91
2022c19:dd:c25:c25:dd:dd:dd:ad92/1272c19:dd:c25:c25:dd:dd:dd:ad93
2032c19:dd:c25:c25:dd:dd:dd:ad94/1272c19:dd:c25:c25:dd:dd:dd:ad95
2042c19:dd:c25:c25:dd:dd:dd:ad96/1272c19:dd:c25:c25:dd:dd:dd:ad97
2052c19:dd:c25:c25:dd:dd:dd:ad98/1272c19:dd:c25:c25:dd:dd:dd:ad99
2062c19:dd:c25:c25:dd:dd:dd:ad9a/1272c19:dd:c25:c25:dd:dd:dd:ad9b
2072c19:dd:c25:c25:dd:dd:dd:ad9c/1272c19:dd:c25:c25:dd:dd:dd:ad9d
2082c19:dd:c25:c25:dd:dd:dd:ad9e/1272c19:dd:c25:c25:dd:dd:dd:ad9f
2092c19:dd:c25:c25:dd:dd:dd:ada0/1272c19:dd:c25:c25:dd:dd:dd:ada1
2102c19:dd:c25:c25:dd:dd:dd:ada2/1272c19:dd:c25:c25:dd:dd:dd:ada3
2112c19:dd:c25:c25:dd:dd:dd:ada4/1272c19:dd:c25:c25:dd:dd:dd:ada5
2122c19:dd:c25:c25:dd:dd:dd:ada6/1272c19:dd:c25:c25:dd:dd:dd:ada7
2132c19:dd:c25:c25:dd:dd:dd:ada8/1272c19:dd:c25:c25:dd:dd:dd:ada9
2142c19:dd:c25:c25:dd:dd:dd:adaa/1272c19:dd:c25:c25:dd:dd:dd:adab
2152c19:dd:c25:c25:dd:dd:dd:adac/1272c19:dd:c25:c25:dd:dd:dd:adad
2162c19:dd:c25:c25:dd:dd:dd:adae/1272c19:dd:c25:c25:dd:dd:dd:adaf
2172c19:dd:c25:c25:dd:dd:dd:adb0/1272c19:dd:c25:c25:dd:dd:dd:adb1
2182c19:dd:c25:c25:dd:dd:dd:adb2/1272c19:dd:c25:c25:dd:dd:dd:adb3
2192c19:dd:c25:c25:dd:dd:dd:adb4/1272c19:dd:c25:c25:dd:dd:dd:adb5
2202c19:dd:c25:c25:dd:dd:dd:adb6/1272c19:dd:c25:c25:dd:dd:dd:adb7
2212c19:dd:c25:c25:dd:dd:dd:adb8/1272c19:dd:c25:c25:dd:dd:dd:adb9
2222c19:dd:c25:c25:dd:dd:dd:adba/1272c19:dd:c25:c25:dd:dd:dd:adbb
2232c19:dd:c25:c25:dd:dd:dd:adbc/1272c19:dd:c25:c25:dd:dd:dd:adbd
2242c19:dd:c25:c25:dd:dd:dd:adbe/1272c19:dd:c25:c25:dd:dd:dd:adbf
2252c19:dd:c25:c25:dd:dd:dd:adc0/1272c19:dd:c25:c25:dd:dd:dd:adc1
2262c19:dd:c25:c25:dd:dd:dd:adc2/1272c19:dd:c25:c25:dd:dd:dd:adc3
2272c19:dd:c25:c25:dd:dd:dd:adc4/1272c19:dd:c25:c25:dd:dd:dd:adc5
2282c19:dd:c25:c25:dd:dd:dd:adc6/1272c19:dd:c25:c25:dd:dd:dd:adc7
2292c19:dd:c25:c25:dd:dd:dd:adc8/1272c19:dd:c25:c25:dd:dd:dd:adc9
2302c19:dd:c25:c25:dd:dd:dd:adca/1272c19:dd:c25:c25:dd:dd:dd:adcb
2312c19:dd:c25:c25:dd:dd:dd:adcc/1272c19:dd:c25:c25:dd:dd:dd:adcd
2322c19:dd:c25:c25:dd:dd:dd:adce/1272c19:dd:c25:c25:dd:dd:dd:adcf
2332c19:dd:c25:c25:dd:dd:dd:add0/1272c19:dd:c25:c25:dd:dd:dd:add1
2342c19:dd:c25:c25:dd:dd:dd:add2/1272c19:dd:c25:c25:dd:dd:dd:add3
2352c19:dd:c25:c25:dd:dd:dd:add4/1272c19:dd:c25:c25:dd:dd:dd:add5
2362c19:dd:c25:c25:dd:dd:dd:add6/1272c19:dd:c25:c25:dd:dd:dd:add7
2372c19:dd:c25:c25:dd:dd:dd:add8/1272c19:dd:c25:c25:dd:dd:dd:add9
2382c19:dd:c25:c25:dd:dd:dd:adda/1272c19:dd:c25:c25:dd:dd:dd:addb
2392c19:dd:c25:c25:dd:dd:dd:addc/1272c19:dd:c25:c25:dd:dd:dd:addd
2402c19:dd:c25:c25:dd:dd:dd:adde/1272c19:dd:c25:c25:dd:dd:dd:addf
2412c19:dd:c25:c25:dd:dd:dd:ade0/1272c19:dd:c25:c25:dd:dd:dd:ade1
2422c19:dd:c25:c25:dd:dd:dd:ade2/1272c19:dd:c25:c25:dd:dd:dd:ade3
2432c19:dd:c25:c25:dd:dd:dd:ade4/1272c19:dd:c25:c25:dd:dd:dd:ade5
2442c19:dd:c25:c25:dd:dd:dd:ade6/1272c19:dd:c25:c25:dd:dd:dd:ade7
2452c19:dd:c25:c25:dd:dd:dd:ade8/1272c19:dd:c25:c25:dd:dd:dd:ade9
2462c19:dd:c25:c25:dd:dd:dd:adea/1272c19:dd:c25:c25:dd:dd:dd:adeb
2472c19:dd:c25:c25:dd:dd:dd:adec/1272c19:dd:c25:c25:dd:dd:dd:aded
2482c19:dd:c25:c25:dd:dd:dd:adee/1272c19:dd:c25:c25:dd:dd:dd:adef
2492c19:dd:c25:c25:dd:dd:dd:adf0/1272c19:dd:c25:c25:dd:dd:dd:adf1
2502c19:dd:c25:c25:dd:dd:dd:adf2/1272c19:dd:c25:c25:dd:dd:dd:adf3
2512c19:dd:c25:c25:dd:dd:dd:adf4/1272c19:dd:c25:c25:dd:dd:dd:adf5
2522c19:dd:c25:c25:dd:dd:dd:adf6/1272c19:dd:c25:c25:dd:dd:dd:adf7
2532c19:dd:c25:c25:dd:dd:dd:adf8/1272c19:dd:c25:c25:dd:dd:dd:adf9
2542c19:dd:c25:c25:dd:dd:dd:adfa/1272c19:dd:c25:c25:dd:dd:dd:adfb
2552c19:dd:c25:c25:dd:dd:dd:adfc/1272c19:dd:c25:c25:dd:dd:dd:adfd
2562c19:dd:c25:c25:dd:dd:dd:adfe/1272c19:dd:c25:c25:dd:dd:dd:adff

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.