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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:c25d:dd:dd:dd:be00/119
First address
2c19:dd:c25:c25d:dd:dd:dd:be00
Last address
2c19:dd:c25:c25d:dd:dd:dd:bfff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:be00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
e.b.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
f.b.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.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:c25d:dd:dd:dd:be00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:be00/1272c19:dd:c25:c25d:dd:dd:dd:be01
22c19:dd:c25:c25d:dd:dd:dd:be02/1272c19:dd:c25:c25d:dd:dd:dd:be03
32c19:dd:c25:c25d:dd:dd:dd:be04/1272c19:dd:c25:c25d:dd:dd:dd:be05
42c19:dd:c25:c25d:dd:dd:dd:be06/1272c19:dd:c25:c25d:dd:dd:dd:be07
52c19:dd:c25:c25d:dd:dd:dd:be08/1272c19:dd:c25:c25d:dd:dd:dd:be09
62c19:dd:c25:c25d:dd:dd:dd:be0a/1272c19:dd:c25:c25d:dd:dd:dd:be0b
72c19:dd:c25:c25d:dd:dd:dd:be0c/1272c19:dd:c25:c25d:dd:dd:dd:be0d
82c19:dd:c25:c25d:dd:dd:dd:be0e/1272c19:dd:c25:c25d:dd:dd:dd:be0f
92c19:dd:c25:c25d:dd:dd:dd:be10/1272c19:dd:c25:c25d:dd:dd:dd:be11
102c19:dd:c25:c25d:dd:dd:dd:be12/1272c19:dd:c25:c25d:dd:dd:dd:be13
112c19:dd:c25:c25d:dd:dd:dd:be14/1272c19:dd:c25:c25d:dd:dd:dd:be15
122c19:dd:c25:c25d:dd:dd:dd:be16/1272c19:dd:c25:c25d:dd:dd:dd:be17
132c19:dd:c25:c25d:dd:dd:dd:be18/1272c19:dd:c25:c25d:dd:dd:dd:be19
142c19:dd:c25:c25d:dd:dd:dd:be1a/1272c19:dd:c25:c25d:dd:dd:dd:be1b
152c19:dd:c25:c25d:dd:dd:dd:be1c/1272c19:dd:c25:c25d:dd:dd:dd:be1d
162c19:dd:c25:c25d:dd:dd:dd:be1e/1272c19:dd:c25:c25d:dd:dd:dd:be1f
172c19:dd:c25:c25d:dd:dd:dd:be20/1272c19:dd:c25:c25d:dd:dd:dd:be21
182c19:dd:c25:c25d:dd:dd:dd:be22/1272c19:dd:c25:c25d:dd:dd:dd:be23
192c19:dd:c25:c25d:dd:dd:dd:be24/1272c19:dd:c25:c25d:dd:dd:dd:be25
202c19:dd:c25:c25d:dd:dd:dd:be26/1272c19:dd:c25:c25d:dd:dd:dd:be27
212c19:dd:c25:c25d:dd:dd:dd:be28/1272c19:dd:c25:c25d:dd:dd:dd:be29
222c19:dd:c25:c25d:dd:dd:dd:be2a/1272c19:dd:c25:c25d:dd:dd:dd:be2b
232c19:dd:c25:c25d:dd:dd:dd:be2c/1272c19:dd:c25:c25d:dd:dd:dd:be2d
242c19:dd:c25:c25d:dd:dd:dd:be2e/1272c19:dd:c25:c25d:dd:dd:dd:be2f
252c19:dd:c25:c25d:dd:dd:dd:be30/1272c19:dd:c25:c25d:dd:dd:dd:be31
262c19:dd:c25:c25d:dd:dd:dd:be32/1272c19:dd:c25:c25d:dd:dd:dd:be33
272c19:dd:c25:c25d:dd:dd:dd:be34/1272c19:dd:c25:c25d:dd:dd:dd:be35
282c19:dd:c25:c25d:dd:dd:dd:be36/1272c19:dd:c25:c25d:dd:dd:dd:be37
292c19:dd:c25:c25d:dd:dd:dd:be38/1272c19:dd:c25:c25d:dd:dd:dd:be39
302c19:dd:c25:c25d:dd:dd:dd:be3a/1272c19:dd:c25:c25d:dd:dd:dd:be3b
312c19:dd:c25:c25d:dd:dd:dd:be3c/1272c19:dd:c25:c25d:dd:dd:dd:be3d
322c19:dd:c25:c25d:dd:dd:dd:be3e/1272c19:dd:c25:c25d:dd:dd:dd:be3f
332c19:dd:c25:c25d:dd:dd:dd:be40/1272c19:dd:c25:c25d:dd:dd:dd:be41
342c19:dd:c25:c25d:dd:dd:dd:be42/1272c19:dd:c25:c25d:dd:dd:dd:be43
352c19:dd:c25:c25d:dd:dd:dd:be44/1272c19:dd:c25:c25d:dd:dd:dd:be45
362c19:dd:c25:c25d:dd:dd:dd:be46/1272c19:dd:c25:c25d:dd:dd:dd:be47
372c19:dd:c25:c25d:dd:dd:dd:be48/1272c19:dd:c25:c25d:dd:dd:dd:be49
382c19:dd:c25:c25d:dd:dd:dd:be4a/1272c19:dd:c25:c25d:dd:dd:dd:be4b
392c19:dd:c25:c25d:dd:dd:dd:be4c/1272c19:dd:c25:c25d:dd:dd:dd:be4d
402c19:dd:c25:c25d:dd:dd:dd:be4e/1272c19:dd:c25:c25d:dd:dd:dd:be4f
412c19:dd:c25:c25d:dd:dd:dd:be50/1272c19:dd:c25:c25d:dd:dd:dd:be51
422c19:dd:c25:c25d:dd:dd:dd:be52/1272c19:dd:c25:c25d:dd:dd:dd:be53
432c19:dd:c25:c25d:dd:dd:dd:be54/1272c19:dd:c25:c25d:dd:dd:dd:be55
442c19:dd:c25:c25d:dd:dd:dd:be56/1272c19:dd:c25:c25d:dd:dd:dd:be57
452c19:dd:c25:c25d:dd:dd:dd:be58/1272c19:dd:c25:c25d:dd:dd:dd:be59
462c19:dd:c25:c25d:dd:dd:dd:be5a/1272c19:dd:c25:c25d:dd:dd:dd:be5b
472c19:dd:c25:c25d:dd:dd:dd:be5c/1272c19:dd:c25:c25d:dd:dd:dd:be5d
482c19:dd:c25:c25d:dd:dd:dd:be5e/1272c19:dd:c25:c25d:dd:dd:dd:be5f
492c19:dd:c25:c25d:dd:dd:dd:be60/1272c19:dd:c25:c25d:dd:dd:dd:be61
502c19:dd:c25:c25d:dd:dd:dd:be62/1272c19:dd:c25:c25d:dd:dd:dd:be63
512c19:dd:c25:c25d:dd:dd:dd:be64/1272c19:dd:c25:c25d:dd:dd:dd:be65
522c19:dd:c25:c25d:dd:dd:dd:be66/1272c19:dd:c25:c25d:dd:dd:dd:be67
532c19:dd:c25:c25d:dd:dd:dd:be68/1272c19:dd:c25:c25d:dd:dd:dd:be69
542c19:dd:c25:c25d:dd:dd:dd:be6a/1272c19:dd:c25:c25d:dd:dd:dd:be6b
552c19:dd:c25:c25d:dd:dd:dd:be6c/1272c19:dd:c25:c25d:dd:dd:dd:be6d
562c19:dd:c25:c25d:dd:dd:dd:be6e/1272c19:dd:c25:c25d:dd:dd:dd:be6f
572c19:dd:c25:c25d:dd:dd:dd:be70/1272c19:dd:c25:c25d:dd:dd:dd:be71
582c19:dd:c25:c25d:dd:dd:dd:be72/1272c19:dd:c25:c25d:dd:dd:dd:be73
592c19:dd:c25:c25d:dd:dd:dd:be74/1272c19:dd:c25:c25d:dd:dd:dd:be75
602c19:dd:c25:c25d:dd:dd:dd:be76/1272c19:dd:c25:c25d:dd:dd:dd:be77
612c19:dd:c25:c25d:dd:dd:dd:be78/1272c19:dd:c25:c25d:dd:dd:dd:be79
622c19:dd:c25:c25d:dd:dd:dd:be7a/1272c19:dd:c25:c25d:dd:dd:dd:be7b
632c19:dd:c25:c25d:dd:dd:dd:be7c/1272c19:dd:c25:c25d:dd:dd:dd:be7d
642c19:dd:c25:c25d:dd:dd:dd:be7e/1272c19:dd:c25:c25d:dd:dd:dd:be7f
652c19:dd:c25:c25d:dd:dd:dd:be80/1272c19:dd:c25:c25d:dd:dd:dd:be81
662c19:dd:c25:c25d:dd:dd:dd:be82/1272c19:dd:c25:c25d:dd:dd:dd:be83
672c19:dd:c25:c25d:dd:dd:dd:be84/1272c19:dd:c25:c25d:dd:dd:dd:be85
682c19:dd:c25:c25d:dd:dd:dd:be86/1272c19:dd:c25:c25d:dd:dd:dd:be87
692c19:dd:c25:c25d:dd:dd:dd:be88/1272c19:dd:c25:c25d:dd:dd:dd:be89
702c19:dd:c25:c25d:dd:dd:dd:be8a/1272c19:dd:c25:c25d:dd:dd:dd:be8b
712c19:dd:c25:c25d:dd:dd:dd:be8c/1272c19:dd:c25:c25d:dd:dd:dd:be8d
722c19:dd:c25:c25d:dd:dd:dd:be8e/1272c19:dd:c25:c25d:dd:dd:dd:be8f
732c19:dd:c25:c25d:dd:dd:dd:be90/1272c19:dd:c25:c25d:dd:dd:dd:be91
742c19:dd:c25:c25d:dd:dd:dd:be92/1272c19:dd:c25:c25d:dd:dd:dd:be93
752c19:dd:c25:c25d:dd:dd:dd:be94/1272c19:dd:c25:c25d:dd:dd:dd:be95
762c19:dd:c25:c25d:dd:dd:dd:be96/1272c19:dd:c25:c25d:dd:dd:dd:be97
772c19:dd:c25:c25d:dd:dd:dd:be98/1272c19:dd:c25:c25d:dd:dd:dd:be99
782c19:dd:c25:c25d:dd:dd:dd:be9a/1272c19:dd:c25:c25d:dd:dd:dd:be9b
792c19:dd:c25:c25d:dd:dd:dd:be9c/1272c19:dd:c25:c25d:dd:dd:dd:be9d
802c19:dd:c25:c25d:dd:dd:dd:be9e/1272c19:dd:c25:c25d:dd:dd:dd:be9f
812c19:dd:c25:c25d:dd:dd:dd:bea0/1272c19:dd:c25:c25d:dd:dd:dd:bea1
822c19:dd:c25:c25d:dd:dd:dd:bea2/1272c19:dd:c25:c25d:dd:dd:dd:bea3
832c19:dd:c25:c25d:dd:dd:dd:bea4/1272c19:dd:c25:c25d:dd:dd:dd:bea5
842c19:dd:c25:c25d:dd:dd:dd:bea6/1272c19:dd:c25:c25d:dd:dd:dd:bea7
852c19:dd:c25:c25d:dd:dd:dd:bea8/1272c19:dd:c25:c25d:dd:dd:dd:bea9
862c19:dd:c25:c25d:dd:dd:dd:beaa/1272c19:dd:c25:c25d:dd:dd:dd:beab
872c19:dd:c25:c25d:dd:dd:dd:beac/1272c19:dd:c25:c25d:dd:dd:dd:bead
882c19:dd:c25:c25d:dd:dd:dd:beae/1272c19:dd:c25:c25d:dd:dd:dd:beaf
892c19:dd:c25:c25d:dd:dd:dd:beb0/1272c19:dd:c25:c25d:dd:dd:dd:beb1
902c19:dd:c25:c25d:dd:dd:dd:beb2/1272c19:dd:c25:c25d:dd:dd:dd:beb3
912c19:dd:c25:c25d:dd:dd:dd:beb4/1272c19:dd:c25:c25d:dd:dd:dd:beb5
922c19:dd:c25:c25d:dd:dd:dd:beb6/1272c19:dd:c25:c25d:dd:dd:dd:beb7
932c19:dd:c25:c25d:dd:dd:dd:beb8/1272c19:dd:c25:c25d:dd:dd:dd:beb9
942c19:dd:c25:c25d:dd:dd:dd:beba/1272c19:dd:c25:c25d:dd:dd:dd:bebb
952c19:dd:c25:c25d:dd:dd:dd:bebc/1272c19:dd:c25:c25d:dd:dd:dd:bebd
962c19:dd:c25:c25d:dd:dd:dd:bebe/1272c19:dd:c25:c25d:dd:dd:dd:bebf
972c19:dd:c25:c25d:dd:dd:dd:bec0/1272c19:dd:c25:c25d:dd:dd:dd:bec1
982c19:dd:c25:c25d:dd:dd:dd:bec2/1272c19:dd:c25:c25d:dd:dd:dd:bec3
992c19:dd:c25:c25d:dd:dd:dd:bec4/1272c19:dd:c25:c25d:dd:dd:dd:bec5
1002c19:dd:c25:c25d:dd:dd:dd:bec6/1272c19:dd:c25:c25d:dd:dd:dd:bec7
1012c19:dd:c25:c25d:dd:dd:dd:bec8/1272c19:dd:c25:c25d:dd:dd:dd:bec9
1022c19:dd:c25:c25d:dd:dd:dd:beca/1272c19:dd:c25:c25d:dd:dd:dd:becb
1032c19:dd:c25:c25d:dd:dd:dd:becc/1272c19:dd:c25:c25d:dd:dd:dd:becd
1042c19:dd:c25:c25d:dd:dd:dd:bece/1272c19:dd:c25:c25d:dd:dd:dd:becf
1052c19:dd:c25:c25d:dd:dd:dd:bed0/1272c19:dd:c25:c25d:dd:dd:dd:bed1
1062c19:dd:c25:c25d:dd:dd:dd:bed2/1272c19:dd:c25:c25d:dd:dd:dd:bed3
1072c19:dd:c25:c25d:dd:dd:dd:bed4/1272c19:dd:c25:c25d:dd:dd:dd:bed5
1082c19:dd:c25:c25d:dd:dd:dd:bed6/1272c19:dd:c25:c25d:dd:dd:dd:bed7
1092c19:dd:c25:c25d:dd:dd:dd:bed8/1272c19:dd:c25:c25d:dd:dd:dd:bed9
1102c19:dd:c25:c25d:dd:dd:dd:beda/1272c19:dd:c25:c25d:dd:dd:dd:bedb
1112c19:dd:c25:c25d:dd:dd:dd:bedc/1272c19:dd:c25:c25d:dd:dd:dd:bedd
1122c19:dd:c25:c25d:dd:dd:dd:bede/1272c19:dd:c25:c25d:dd:dd:dd:bedf
1132c19:dd:c25:c25d:dd:dd:dd:bee0/1272c19:dd:c25:c25d:dd:dd:dd:bee1
1142c19:dd:c25:c25d:dd:dd:dd:bee2/1272c19:dd:c25:c25d:dd:dd:dd:bee3
1152c19:dd:c25:c25d:dd:dd:dd:bee4/1272c19:dd:c25:c25d:dd:dd:dd:bee5
1162c19:dd:c25:c25d:dd:dd:dd:bee6/1272c19:dd:c25:c25d:dd:dd:dd:bee7
1172c19:dd:c25:c25d:dd:dd:dd:bee8/1272c19:dd:c25:c25d:dd:dd:dd:bee9
1182c19:dd:c25:c25d:dd:dd:dd:beea/1272c19:dd:c25:c25d:dd:dd:dd:beeb
1192c19:dd:c25:c25d:dd:dd:dd:beec/1272c19:dd:c25:c25d:dd:dd:dd:beed
1202c19:dd:c25:c25d:dd:dd:dd:beee/1272c19:dd:c25:c25d:dd:dd:dd:beef
1212c19:dd:c25:c25d:dd:dd:dd:bef0/1272c19:dd:c25:c25d:dd:dd:dd:bef1
1222c19:dd:c25:c25d:dd:dd:dd:bef2/1272c19:dd:c25:c25d:dd:dd:dd:bef3
1232c19:dd:c25:c25d:dd:dd:dd:bef4/1272c19:dd:c25:c25d:dd:dd:dd:bef5
1242c19:dd:c25:c25d:dd:dd:dd:bef6/1272c19:dd:c25:c25d:dd:dd:dd:bef7
1252c19:dd:c25:c25d:dd:dd:dd:bef8/1272c19:dd:c25:c25d:dd:dd:dd:bef9
1262c19:dd:c25:c25d:dd:dd:dd:befa/1272c19:dd:c25:c25d:dd:dd:dd:befb
1272c19:dd:c25:c25d:dd:dd:dd:befc/1272c19:dd:c25:c25d:dd:dd:dd:befd
1282c19:dd:c25:c25d:dd:dd:dd:befe/1272c19:dd:c25:c25d:dd:dd:dd:beff
1292c19:dd:c25:c25d:dd:dd:dd:bf00/1272c19:dd:c25:c25d:dd:dd:dd:bf01
1302c19:dd:c25:c25d:dd:dd:dd:bf02/1272c19:dd:c25:c25d:dd:dd:dd:bf03
1312c19:dd:c25:c25d:dd:dd:dd:bf04/1272c19:dd:c25:c25d:dd:dd:dd:bf05
1322c19:dd:c25:c25d:dd:dd:dd:bf06/1272c19:dd:c25:c25d:dd:dd:dd:bf07
1332c19:dd:c25:c25d:dd:dd:dd:bf08/1272c19:dd:c25:c25d:dd:dd:dd:bf09
1342c19:dd:c25:c25d:dd:dd:dd:bf0a/1272c19:dd:c25:c25d:dd:dd:dd:bf0b
1352c19:dd:c25:c25d:dd:dd:dd:bf0c/1272c19:dd:c25:c25d:dd:dd:dd:bf0d
1362c19:dd:c25:c25d:dd:dd:dd:bf0e/1272c19:dd:c25:c25d:dd:dd:dd:bf0f
1372c19:dd:c25:c25d:dd:dd:dd:bf10/1272c19:dd:c25:c25d:dd:dd:dd:bf11
1382c19:dd:c25:c25d:dd:dd:dd:bf12/1272c19:dd:c25:c25d:dd:dd:dd:bf13
1392c19:dd:c25:c25d:dd:dd:dd:bf14/1272c19:dd:c25:c25d:dd:dd:dd:bf15
1402c19:dd:c25:c25d:dd:dd:dd:bf16/1272c19:dd:c25:c25d:dd:dd:dd:bf17
1412c19:dd:c25:c25d:dd:dd:dd:bf18/1272c19:dd:c25:c25d:dd:dd:dd:bf19
1422c19:dd:c25:c25d:dd:dd:dd:bf1a/1272c19:dd:c25:c25d:dd:dd:dd:bf1b
1432c19:dd:c25:c25d:dd:dd:dd:bf1c/1272c19:dd:c25:c25d:dd:dd:dd:bf1d
1442c19:dd:c25:c25d:dd:dd:dd:bf1e/1272c19:dd:c25:c25d:dd:dd:dd:bf1f
1452c19:dd:c25:c25d:dd:dd:dd:bf20/1272c19:dd:c25:c25d:dd:dd:dd:bf21
1462c19:dd:c25:c25d:dd:dd:dd:bf22/1272c19:dd:c25:c25d:dd:dd:dd:bf23
1472c19:dd:c25:c25d:dd:dd:dd:bf24/1272c19:dd:c25:c25d:dd:dd:dd:bf25
1482c19:dd:c25:c25d:dd:dd:dd:bf26/1272c19:dd:c25:c25d:dd:dd:dd:bf27
1492c19:dd:c25:c25d:dd:dd:dd:bf28/1272c19:dd:c25:c25d:dd:dd:dd:bf29
1502c19:dd:c25:c25d:dd:dd:dd:bf2a/1272c19:dd:c25:c25d:dd:dd:dd:bf2b
1512c19:dd:c25:c25d:dd:dd:dd:bf2c/1272c19:dd:c25:c25d:dd:dd:dd:bf2d
1522c19:dd:c25:c25d:dd:dd:dd:bf2e/1272c19:dd:c25:c25d:dd:dd:dd:bf2f
1532c19:dd:c25:c25d:dd:dd:dd:bf30/1272c19:dd:c25:c25d:dd:dd:dd:bf31
1542c19:dd:c25:c25d:dd:dd:dd:bf32/1272c19:dd:c25:c25d:dd:dd:dd:bf33
1552c19:dd:c25:c25d:dd:dd:dd:bf34/1272c19:dd:c25:c25d:dd:dd:dd:bf35
1562c19:dd:c25:c25d:dd:dd:dd:bf36/1272c19:dd:c25:c25d:dd:dd:dd:bf37
1572c19:dd:c25:c25d:dd:dd:dd:bf38/1272c19:dd:c25:c25d:dd:dd:dd:bf39
1582c19:dd:c25:c25d:dd:dd:dd:bf3a/1272c19:dd:c25:c25d:dd:dd:dd:bf3b
1592c19:dd:c25:c25d:dd:dd:dd:bf3c/1272c19:dd:c25:c25d:dd:dd:dd:bf3d
1602c19:dd:c25:c25d:dd:dd:dd:bf3e/1272c19:dd:c25:c25d:dd:dd:dd:bf3f
1612c19:dd:c25:c25d:dd:dd:dd:bf40/1272c19:dd:c25:c25d:dd:dd:dd:bf41
1622c19:dd:c25:c25d:dd:dd:dd:bf42/1272c19:dd:c25:c25d:dd:dd:dd:bf43
1632c19:dd:c25:c25d:dd:dd:dd:bf44/1272c19:dd:c25:c25d:dd:dd:dd:bf45
1642c19:dd:c25:c25d:dd:dd:dd:bf46/1272c19:dd:c25:c25d:dd:dd:dd:bf47
1652c19:dd:c25:c25d:dd:dd:dd:bf48/1272c19:dd:c25:c25d:dd:dd:dd:bf49
1662c19:dd:c25:c25d:dd:dd:dd:bf4a/1272c19:dd:c25:c25d:dd:dd:dd:bf4b
1672c19:dd:c25:c25d:dd:dd:dd:bf4c/1272c19:dd:c25:c25d:dd:dd:dd:bf4d
1682c19:dd:c25:c25d:dd:dd:dd:bf4e/1272c19:dd:c25:c25d:dd:dd:dd:bf4f
1692c19:dd:c25:c25d:dd:dd:dd:bf50/1272c19:dd:c25:c25d:dd:dd:dd:bf51
1702c19:dd:c25:c25d:dd:dd:dd:bf52/1272c19:dd:c25:c25d:dd:dd:dd:bf53
1712c19:dd:c25:c25d:dd:dd:dd:bf54/1272c19:dd:c25:c25d:dd:dd:dd:bf55
1722c19:dd:c25:c25d:dd:dd:dd:bf56/1272c19:dd:c25:c25d:dd:dd:dd:bf57
1732c19:dd:c25:c25d:dd:dd:dd:bf58/1272c19:dd:c25:c25d:dd:dd:dd:bf59
1742c19:dd:c25:c25d:dd:dd:dd:bf5a/1272c19:dd:c25:c25d:dd:dd:dd:bf5b
1752c19:dd:c25:c25d:dd:dd:dd:bf5c/1272c19:dd:c25:c25d:dd:dd:dd:bf5d
1762c19:dd:c25:c25d:dd:dd:dd:bf5e/1272c19:dd:c25:c25d:dd:dd:dd:bf5f
1772c19:dd:c25:c25d:dd:dd:dd:bf60/1272c19:dd:c25:c25d:dd:dd:dd:bf61
1782c19:dd:c25:c25d:dd:dd:dd:bf62/1272c19:dd:c25:c25d:dd:dd:dd:bf63
1792c19:dd:c25:c25d:dd:dd:dd:bf64/1272c19:dd:c25:c25d:dd:dd:dd:bf65
1802c19:dd:c25:c25d:dd:dd:dd:bf66/1272c19:dd:c25:c25d:dd:dd:dd:bf67
1812c19:dd:c25:c25d:dd:dd:dd:bf68/1272c19:dd:c25:c25d:dd:dd:dd:bf69
1822c19:dd:c25:c25d:dd:dd:dd:bf6a/1272c19:dd:c25:c25d:dd:dd:dd:bf6b
1832c19:dd:c25:c25d:dd:dd:dd:bf6c/1272c19:dd:c25:c25d:dd:dd:dd:bf6d
1842c19:dd:c25:c25d:dd:dd:dd:bf6e/1272c19:dd:c25:c25d:dd:dd:dd:bf6f
1852c19:dd:c25:c25d:dd:dd:dd:bf70/1272c19:dd:c25:c25d:dd:dd:dd:bf71
1862c19:dd:c25:c25d:dd:dd:dd:bf72/1272c19:dd:c25:c25d:dd:dd:dd:bf73
1872c19:dd:c25:c25d:dd:dd:dd:bf74/1272c19:dd:c25:c25d:dd:dd:dd:bf75
1882c19:dd:c25:c25d:dd:dd:dd:bf76/1272c19:dd:c25:c25d:dd:dd:dd:bf77
1892c19:dd:c25:c25d:dd:dd:dd:bf78/1272c19:dd:c25:c25d:dd:dd:dd:bf79
1902c19:dd:c25:c25d:dd:dd:dd:bf7a/1272c19:dd:c25:c25d:dd:dd:dd:bf7b
1912c19:dd:c25:c25d:dd:dd:dd:bf7c/1272c19:dd:c25:c25d:dd:dd:dd:bf7d
1922c19:dd:c25:c25d:dd:dd:dd:bf7e/1272c19:dd:c25:c25d:dd:dd:dd:bf7f
1932c19:dd:c25:c25d:dd:dd:dd:bf80/1272c19:dd:c25:c25d:dd:dd:dd:bf81
1942c19:dd:c25:c25d:dd:dd:dd:bf82/1272c19:dd:c25:c25d:dd:dd:dd:bf83
1952c19:dd:c25:c25d:dd:dd:dd:bf84/1272c19:dd:c25:c25d:dd:dd:dd:bf85
1962c19:dd:c25:c25d:dd:dd:dd:bf86/1272c19:dd:c25:c25d:dd:dd:dd:bf87
1972c19:dd:c25:c25d:dd:dd:dd:bf88/1272c19:dd:c25:c25d:dd:dd:dd:bf89
1982c19:dd:c25:c25d:dd:dd:dd:bf8a/1272c19:dd:c25:c25d:dd:dd:dd:bf8b
1992c19:dd:c25:c25d:dd:dd:dd:bf8c/1272c19:dd:c25:c25d:dd:dd:dd:bf8d
2002c19:dd:c25:c25d:dd:dd:dd:bf8e/1272c19:dd:c25:c25d:dd:dd:dd:bf8f
2012c19:dd:c25:c25d:dd:dd:dd:bf90/1272c19:dd:c25:c25d:dd:dd:dd:bf91
2022c19:dd:c25:c25d:dd:dd:dd:bf92/1272c19:dd:c25:c25d:dd:dd:dd:bf93
2032c19:dd:c25:c25d:dd:dd:dd:bf94/1272c19:dd:c25:c25d:dd:dd:dd:bf95
2042c19:dd:c25:c25d:dd:dd:dd:bf96/1272c19:dd:c25:c25d:dd:dd:dd:bf97
2052c19:dd:c25:c25d:dd:dd:dd:bf98/1272c19:dd:c25:c25d:dd:dd:dd:bf99
2062c19:dd:c25:c25d:dd:dd:dd:bf9a/1272c19:dd:c25:c25d:dd:dd:dd:bf9b
2072c19:dd:c25:c25d:dd:dd:dd:bf9c/1272c19:dd:c25:c25d:dd:dd:dd:bf9d
2082c19:dd:c25:c25d:dd:dd:dd:bf9e/1272c19:dd:c25:c25d:dd:dd:dd:bf9f
2092c19:dd:c25:c25d:dd:dd:dd:bfa0/1272c19:dd:c25:c25d:dd:dd:dd:bfa1
2102c19:dd:c25:c25d:dd:dd:dd:bfa2/1272c19:dd:c25:c25d:dd:dd:dd:bfa3
2112c19:dd:c25:c25d:dd:dd:dd:bfa4/1272c19:dd:c25:c25d:dd:dd:dd:bfa5
2122c19:dd:c25:c25d:dd:dd:dd:bfa6/1272c19:dd:c25:c25d:dd:dd:dd:bfa7
2132c19:dd:c25:c25d:dd:dd:dd:bfa8/1272c19:dd:c25:c25d:dd:dd:dd:bfa9
2142c19:dd:c25:c25d:dd:dd:dd:bfaa/1272c19:dd:c25:c25d:dd:dd:dd:bfab
2152c19:dd:c25:c25d:dd:dd:dd:bfac/1272c19:dd:c25:c25d:dd:dd:dd:bfad
2162c19:dd:c25:c25d:dd:dd:dd:bfae/1272c19:dd:c25:c25d:dd:dd:dd:bfaf
2172c19:dd:c25:c25d:dd:dd:dd:bfb0/1272c19:dd:c25:c25d:dd:dd:dd:bfb1
2182c19:dd:c25:c25d:dd:dd:dd:bfb2/1272c19:dd:c25:c25d:dd:dd:dd:bfb3
2192c19:dd:c25:c25d:dd:dd:dd:bfb4/1272c19:dd:c25:c25d:dd:dd:dd:bfb5
2202c19:dd:c25:c25d:dd:dd:dd:bfb6/1272c19:dd:c25:c25d:dd:dd:dd:bfb7
2212c19:dd:c25:c25d:dd:dd:dd:bfb8/1272c19:dd:c25:c25d:dd:dd:dd:bfb9
2222c19:dd:c25:c25d:dd:dd:dd:bfba/1272c19:dd:c25:c25d:dd:dd:dd:bfbb
2232c19:dd:c25:c25d:dd:dd:dd:bfbc/1272c19:dd:c25:c25d:dd:dd:dd:bfbd
2242c19:dd:c25:c25d:dd:dd:dd:bfbe/1272c19:dd:c25:c25d:dd:dd:dd:bfbf
2252c19:dd:c25:c25d:dd:dd:dd:bfc0/1272c19:dd:c25:c25d:dd:dd:dd:bfc1
2262c19:dd:c25:c25d:dd:dd:dd:bfc2/1272c19:dd:c25:c25d:dd:dd:dd:bfc3
2272c19:dd:c25:c25d:dd:dd:dd:bfc4/1272c19:dd:c25:c25d:dd:dd:dd:bfc5
2282c19:dd:c25:c25d:dd:dd:dd:bfc6/1272c19:dd:c25:c25d:dd:dd:dd:bfc7
2292c19:dd:c25:c25d:dd:dd:dd:bfc8/1272c19:dd:c25:c25d:dd:dd:dd:bfc9
2302c19:dd:c25:c25d:dd:dd:dd:bfca/1272c19:dd:c25:c25d:dd:dd:dd:bfcb
2312c19:dd:c25:c25d:dd:dd:dd:bfcc/1272c19:dd:c25:c25d:dd:dd:dd:bfcd
2322c19:dd:c25:c25d:dd:dd:dd:bfce/1272c19:dd:c25:c25d:dd:dd:dd:bfcf
2332c19:dd:c25:c25d:dd:dd:dd:bfd0/1272c19:dd:c25:c25d:dd:dd:dd:bfd1
2342c19:dd:c25:c25d:dd:dd:dd:bfd2/1272c19:dd:c25:c25d:dd:dd:dd:bfd3
2352c19:dd:c25:c25d:dd:dd:dd:bfd4/1272c19:dd:c25:c25d:dd:dd:dd:bfd5
2362c19:dd:c25:c25d:dd:dd:dd:bfd6/1272c19:dd:c25:c25d:dd:dd:dd:bfd7
2372c19:dd:c25:c25d:dd:dd:dd:bfd8/1272c19:dd:c25:c25d:dd:dd:dd:bfd9
2382c19:dd:c25:c25d:dd:dd:dd:bfda/1272c19:dd:c25:c25d:dd:dd:dd:bfdb
2392c19:dd:c25:c25d:dd:dd:dd:bfdc/1272c19:dd:c25:c25d:dd:dd:dd:bfdd
2402c19:dd:c25:c25d:dd:dd:dd:bfde/1272c19:dd:c25:c25d:dd:dd:dd:bfdf
2412c19:dd:c25:c25d:dd:dd:dd:bfe0/1272c19:dd:c25:c25d:dd:dd:dd:bfe1
2422c19:dd:c25:c25d:dd:dd:dd:bfe2/1272c19:dd:c25:c25d:dd:dd:dd:bfe3
2432c19:dd:c25:c25d:dd:dd:dd:bfe4/1272c19:dd:c25:c25d:dd:dd:dd:bfe5
2442c19:dd:c25:c25d:dd:dd:dd:bfe6/1272c19:dd:c25:c25d:dd:dd:dd:bfe7
2452c19:dd:c25:c25d:dd:dd:dd:bfe8/1272c19:dd:c25:c25d:dd:dd:dd:bfe9
2462c19:dd:c25:c25d:dd:dd:dd:bfea/1272c19:dd:c25:c25d:dd:dd:dd:bfeb
2472c19:dd:c25:c25d:dd:dd:dd:bfec/1272c19:dd:c25:c25d:dd:dd:dd:bfed
2482c19:dd:c25:c25d:dd:dd:dd:bfee/1272c19:dd:c25:c25d:dd:dd:dd:bfef
2492c19:dd:c25:c25d:dd:dd:dd:bff0/1272c19:dd:c25:c25d:dd:dd:dd:bff1
2502c19:dd:c25:c25d:dd:dd:dd:bff2/1272c19:dd:c25:c25d:dd:dd:dd:bff3
2512c19:dd:c25:c25d:dd:dd:dd:bff4/1272c19:dd:c25:c25d:dd:dd:dd:bff5
2522c19:dd:c25:c25d:dd:dd:dd:bff6/1272c19:dd:c25:c25d:dd:dd:dd:bff7
2532c19:dd:c25:c25d:dd:dd:dd:bff8/1272c19:dd:c25:c25d:dd:dd:dd:bff9
2542c19:dd:c25:c25d:dd:dd:dd:bffa/1272c19:dd:c25:c25d:dd:dd:dd:bffb
2552c19:dd:c25:c25d:dd:dd:dd:bffc/1272c19:dd:c25:c25d:dd:dd:dd:bffd
2562c19:dd:c25:c25d:dd:dd:dd:bffe/1272c19:dd:c25:c25d:dd:dd:dd:bfff

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.