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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:d00a:fe00/119
First address
2c19:dd:d9:dd:c25:c25:d00a:fe00
Last address
2c19:dd:d9:dd:c25:c25:d00a:ffff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d00a:fe00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
e.f.a.0.0.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
f.f.a.0.0.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:d00a:fe00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d00a:fe00/1272c19:dd:d9:dd:c25:c25:d00a:fe01
22c19:dd:d9:dd:c25:c25:d00a:fe02/1272c19:dd:d9:dd:c25:c25:d00a:fe03
32c19:dd:d9:dd:c25:c25:d00a:fe04/1272c19:dd:d9:dd:c25:c25:d00a:fe05
42c19:dd:d9:dd:c25:c25:d00a:fe06/1272c19:dd:d9:dd:c25:c25:d00a:fe07
52c19:dd:d9:dd:c25:c25:d00a:fe08/1272c19:dd:d9:dd:c25:c25:d00a:fe09
62c19:dd:d9:dd:c25:c25:d00a:fe0a/1272c19:dd:d9:dd:c25:c25:d00a:fe0b
72c19:dd:d9:dd:c25:c25:d00a:fe0c/1272c19:dd:d9:dd:c25:c25:d00a:fe0d
82c19:dd:d9:dd:c25:c25:d00a:fe0e/1272c19:dd:d9:dd:c25:c25:d00a:fe0f
92c19:dd:d9:dd:c25:c25:d00a:fe10/1272c19:dd:d9:dd:c25:c25:d00a:fe11
102c19:dd:d9:dd:c25:c25:d00a:fe12/1272c19:dd:d9:dd:c25:c25:d00a:fe13
112c19:dd:d9:dd:c25:c25:d00a:fe14/1272c19:dd:d9:dd:c25:c25:d00a:fe15
122c19:dd:d9:dd:c25:c25:d00a:fe16/1272c19:dd:d9:dd:c25:c25:d00a:fe17
132c19:dd:d9:dd:c25:c25:d00a:fe18/1272c19:dd:d9:dd:c25:c25:d00a:fe19
142c19:dd:d9:dd:c25:c25:d00a:fe1a/1272c19:dd:d9:dd:c25:c25:d00a:fe1b
152c19:dd:d9:dd:c25:c25:d00a:fe1c/1272c19:dd:d9:dd:c25:c25:d00a:fe1d
162c19:dd:d9:dd:c25:c25:d00a:fe1e/1272c19:dd:d9:dd:c25:c25:d00a:fe1f
172c19:dd:d9:dd:c25:c25:d00a:fe20/1272c19:dd:d9:dd:c25:c25:d00a:fe21
182c19:dd:d9:dd:c25:c25:d00a:fe22/1272c19:dd:d9:dd:c25:c25:d00a:fe23
192c19:dd:d9:dd:c25:c25:d00a:fe24/1272c19:dd:d9:dd:c25:c25:d00a:fe25
202c19:dd:d9:dd:c25:c25:d00a:fe26/1272c19:dd:d9:dd:c25:c25:d00a:fe27
212c19:dd:d9:dd:c25:c25:d00a:fe28/1272c19:dd:d9:dd:c25:c25:d00a:fe29
222c19:dd:d9:dd:c25:c25:d00a:fe2a/1272c19:dd:d9:dd:c25:c25:d00a:fe2b
232c19:dd:d9:dd:c25:c25:d00a:fe2c/1272c19:dd:d9:dd:c25:c25:d00a:fe2d
242c19:dd:d9:dd:c25:c25:d00a:fe2e/1272c19:dd:d9:dd:c25:c25:d00a:fe2f
252c19:dd:d9:dd:c25:c25:d00a:fe30/1272c19:dd:d9:dd:c25:c25:d00a:fe31
262c19:dd:d9:dd:c25:c25:d00a:fe32/1272c19:dd:d9:dd:c25:c25:d00a:fe33
272c19:dd:d9:dd:c25:c25:d00a:fe34/1272c19:dd:d9:dd:c25:c25:d00a:fe35
282c19:dd:d9:dd:c25:c25:d00a:fe36/1272c19:dd:d9:dd:c25:c25:d00a:fe37
292c19:dd:d9:dd:c25:c25:d00a:fe38/1272c19:dd:d9:dd:c25:c25:d00a:fe39
302c19:dd:d9:dd:c25:c25:d00a:fe3a/1272c19:dd:d9:dd:c25:c25:d00a:fe3b
312c19:dd:d9:dd:c25:c25:d00a:fe3c/1272c19:dd:d9:dd:c25:c25:d00a:fe3d
322c19:dd:d9:dd:c25:c25:d00a:fe3e/1272c19:dd:d9:dd:c25:c25:d00a:fe3f
332c19:dd:d9:dd:c25:c25:d00a:fe40/1272c19:dd:d9:dd:c25:c25:d00a:fe41
342c19:dd:d9:dd:c25:c25:d00a:fe42/1272c19:dd:d9:dd:c25:c25:d00a:fe43
352c19:dd:d9:dd:c25:c25:d00a:fe44/1272c19:dd:d9:dd:c25:c25:d00a:fe45
362c19:dd:d9:dd:c25:c25:d00a:fe46/1272c19:dd:d9:dd:c25:c25:d00a:fe47
372c19:dd:d9:dd:c25:c25:d00a:fe48/1272c19:dd:d9:dd:c25:c25:d00a:fe49
382c19:dd:d9:dd:c25:c25:d00a:fe4a/1272c19:dd:d9:dd:c25:c25:d00a:fe4b
392c19:dd:d9:dd:c25:c25:d00a:fe4c/1272c19:dd:d9:dd:c25:c25:d00a:fe4d
402c19:dd:d9:dd:c25:c25:d00a:fe4e/1272c19:dd:d9:dd:c25:c25:d00a:fe4f
412c19:dd:d9:dd:c25:c25:d00a:fe50/1272c19:dd:d9:dd:c25:c25:d00a:fe51
422c19:dd:d9:dd:c25:c25:d00a:fe52/1272c19:dd:d9:dd:c25:c25:d00a:fe53
432c19:dd:d9:dd:c25:c25:d00a:fe54/1272c19:dd:d9:dd:c25:c25:d00a:fe55
442c19:dd:d9:dd:c25:c25:d00a:fe56/1272c19:dd:d9:dd:c25:c25:d00a:fe57
452c19:dd:d9:dd:c25:c25:d00a:fe58/1272c19:dd:d9:dd:c25:c25:d00a:fe59
462c19:dd:d9:dd:c25:c25:d00a:fe5a/1272c19:dd:d9:dd:c25:c25:d00a:fe5b
472c19:dd:d9:dd:c25:c25:d00a:fe5c/1272c19:dd:d9:dd:c25:c25:d00a:fe5d
482c19:dd:d9:dd:c25:c25:d00a:fe5e/1272c19:dd:d9:dd:c25:c25:d00a:fe5f
492c19:dd:d9:dd:c25:c25:d00a:fe60/1272c19:dd:d9:dd:c25:c25:d00a:fe61
502c19:dd:d9:dd:c25:c25:d00a:fe62/1272c19:dd:d9:dd:c25:c25:d00a:fe63
512c19:dd:d9:dd:c25:c25:d00a:fe64/1272c19:dd:d9:dd:c25:c25:d00a:fe65
522c19:dd:d9:dd:c25:c25:d00a:fe66/1272c19:dd:d9:dd:c25:c25:d00a:fe67
532c19:dd:d9:dd:c25:c25:d00a:fe68/1272c19:dd:d9:dd:c25:c25:d00a:fe69
542c19:dd:d9:dd:c25:c25:d00a:fe6a/1272c19:dd:d9:dd:c25:c25:d00a:fe6b
552c19:dd:d9:dd:c25:c25:d00a:fe6c/1272c19:dd:d9:dd:c25:c25:d00a:fe6d
562c19:dd:d9:dd:c25:c25:d00a:fe6e/1272c19:dd:d9:dd:c25:c25:d00a:fe6f
572c19:dd:d9:dd:c25:c25:d00a:fe70/1272c19:dd:d9:dd:c25:c25:d00a:fe71
582c19:dd:d9:dd:c25:c25:d00a:fe72/1272c19:dd:d9:dd:c25:c25:d00a:fe73
592c19:dd:d9:dd:c25:c25:d00a:fe74/1272c19:dd:d9:dd:c25:c25:d00a:fe75
602c19:dd:d9:dd:c25:c25:d00a:fe76/1272c19:dd:d9:dd:c25:c25:d00a:fe77
612c19:dd:d9:dd:c25:c25:d00a:fe78/1272c19:dd:d9:dd:c25:c25:d00a:fe79
622c19:dd:d9:dd:c25:c25:d00a:fe7a/1272c19:dd:d9:dd:c25:c25:d00a:fe7b
632c19:dd:d9:dd:c25:c25:d00a:fe7c/1272c19:dd:d9:dd:c25:c25:d00a:fe7d
642c19:dd:d9:dd:c25:c25:d00a:fe7e/1272c19:dd:d9:dd:c25:c25:d00a:fe7f
652c19:dd:d9:dd:c25:c25:d00a:fe80/1272c19:dd:d9:dd:c25:c25:d00a:fe81
662c19:dd:d9:dd:c25:c25:d00a:fe82/1272c19:dd:d9:dd:c25:c25:d00a:fe83
672c19:dd:d9:dd:c25:c25:d00a:fe84/1272c19:dd:d9:dd:c25:c25:d00a:fe85
682c19:dd:d9:dd:c25:c25:d00a:fe86/1272c19:dd:d9:dd:c25:c25:d00a:fe87
692c19:dd:d9:dd:c25:c25:d00a:fe88/1272c19:dd:d9:dd:c25:c25:d00a:fe89
702c19:dd:d9:dd:c25:c25:d00a:fe8a/1272c19:dd:d9:dd:c25:c25:d00a:fe8b
712c19:dd:d9:dd:c25:c25:d00a:fe8c/1272c19:dd:d9:dd:c25:c25:d00a:fe8d
722c19:dd:d9:dd:c25:c25:d00a:fe8e/1272c19:dd:d9:dd:c25:c25:d00a:fe8f
732c19:dd:d9:dd:c25:c25:d00a:fe90/1272c19:dd:d9:dd:c25:c25:d00a:fe91
742c19:dd:d9:dd:c25:c25:d00a:fe92/1272c19:dd:d9:dd:c25:c25:d00a:fe93
752c19:dd:d9:dd:c25:c25:d00a:fe94/1272c19:dd:d9:dd:c25:c25:d00a:fe95
762c19:dd:d9:dd:c25:c25:d00a:fe96/1272c19:dd:d9:dd:c25:c25:d00a:fe97
772c19:dd:d9:dd:c25:c25:d00a:fe98/1272c19:dd:d9:dd:c25:c25:d00a:fe99
782c19:dd:d9:dd:c25:c25:d00a:fe9a/1272c19:dd:d9:dd:c25:c25:d00a:fe9b
792c19:dd:d9:dd:c25:c25:d00a:fe9c/1272c19:dd:d9:dd:c25:c25:d00a:fe9d
802c19:dd:d9:dd:c25:c25:d00a:fe9e/1272c19:dd:d9:dd:c25:c25:d00a:fe9f
812c19:dd:d9:dd:c25:c25:d00a:fea0/1272c19:dd:d9:dd:c25:c25:d00a:fea1
822c19:dd:d9:dd:c25:c25:d00a:fea2/1272c19:dd:d9:dd:c25:c25:d00a:fea3
832c19:dd:d9:dd:c25:c25:d00a:fea4/1272c19:dd:d9:dd:c25:c25:d00a:fea5
842c19:dd:d9:dd:c25:c25:d00a:fea6/1272c19:dd:d9:dd:c25:c25:d00a:fea7
852c19:dd:d9:dd:c25:c25:d00a:fea8/1272c19:dd:d9:dd:c25:c25:d00a:fea9
862c19:dd:d9:dd:c25:c25:d00a:feaa/1272c19:dd:d9:dd:c25:c25:d00a:feab
872c19:dd:d9:dd:c25:c25:d00a:feac/1272c19:dd:d9:dd:c25:c25:d00a:fead
882c19:dd:d9:dd:c25:c25:d00a:feae/1272c19:dd:d9:dd:c25:c25:d00a:feaf
892c19:dd:d9:dd:c25:c25:d00a:feb0/1272c19:dd:d9:dd:c25:c25:d00a:feb1
902c19:dd:d9:dd:c25:c25:d00a:feb2/1272c19:dd:d9:dd:c25:c25:d00a:feb3
912c19:dd:d9:dd:c25:c25:d00a:feb4/1272c19:dd:d9:dd:c25:c25:d00a:feb5
922c19:dd:d9:dd:c25:c25:d00a:feb6/1272c19:dd:d9:dd:c25:c25:d00a:feb7
932c19:dd:d9:dd:c25:c25:d00a:feb8/1272c19:dd:d9:dd:c25:c25:d00a:feb9
942c19:dd:d9:dd:c25:c25:d00a:feba/1272c19:dd:d9:dd:c25:c25:d00a:febb
952c19:dd:d9:dd:c25:c25:d00a:febc/1272c19:dd:d9:dd:c25:c25:d00a:febd
962c19:dd:d9:dd:c25:c25:d00a:febe/1272c19:dd:d9:dd:c25:c25:d00a:febf
972c19:dd:d9:dd:c25:c25:d00a:fec0/1272c19:dd:d9:dd:c25:c25:d00a:fec1
982c19:dd:d9:dd:c25:c25:d00a:fec2/1272c19:dd:d9:dd:c25:c25:d00a:fec3
992c19:dd:d9:dd:c25:c25:d00a:fec4/1272c19:dd:d9:dd:c25:c25:d00a:fec5
1002c19:dd:d9:dd:c25:c25:d00a:fec6/1272c19:dd:d9:dd:c25:c25:d00a:fec7
1012c19:dd:d9:dd:c25:c25:d00a:fec8/1272c19:dd:d9:dd:c25:c25:d00a:fec9
1022c19:dd:d9:dd:c25:c25:d00a:feca/1272c19:dd:d9:dd:c25:c25:d00a:fecb
1032c19:dd:d9:dd:c25:c25:d00a:fecc/1272c19:dd:d9:dd:c25:c25:d00a:fecd
1042c19:dd:d9:dd:c25:c25:d00a:fece/1272c19:dd:d9:dd:c25:c25:d00a:fecf
1052c19:dd:d9:dd:c25:c25:d00a:fed0/1272c19:dd:d9:dd:c25:c25:d00a:fed1
1062c19:dd:d9:dd:c25:c25:d00a:fed2/1272c19:dd:d9:dd:c25:c25:d00a:fed3
1072c19:dd:d9:dd:c25:c25:d00a:fed4/1272c19:dd:d9:dd:c25:c25:d00a:fed5
1082c19:dd:d9:dd:c25:c25:d00a:fed6/1272c19:dd:d9:dd:c25:c25:d00a:fed7
1092c19:dd:d9:dd:c25:c25:d00a:fed8/1272c19:dd:d9:dd:c25:c25:d00a:fed9
1102c19:dd:d9:dd:c25:c25:d00a:feda/1272c19:dd:d9:dd:c25:c25:d00a:fedb
1112c19:dd:d9:dd:c25:c25:d00a:fedc/1272c19:dd:d9:dd:c25:c25:d00a:fedd
1122c19:dd:d9:dd:c25:c25:d00a:fede/1272c19:dd:d9:dd:c25:c25:d00a:fedf
1132c19:dd:d9:dd:c25:c25:d00a:fee0/1272c19:dd:d9:dd:c25:c25:d00a:fee1
1142c19:dd:d9:dd:c25:c25:d00a:fee2/1272c19:dd:d9:dd:c25:c25:d00a:fee3
1152c19:dd:d9:dd:c25:c25:d00a:fee4/1272c19:dd:d9:dd:c25:c25:d00a:fee5
1162c19:dd:d9:dd:c25:c25:d00a:fee6/1272c19:dd:d9:dd:c25:c25:d00a:fee7
1172c19:dd:d9:dd:c25:c25:d00a:fee8/1272c19:dd:d9:dd:c25:c25:d00a:fee9
1182c19:dd:d9:dd:c25:c25:d00a:feea/1272c19:dd:d9:dd:c25:c25:d00a:feeb
1192c19:dd:d9:dd:c25:c25:d00a:feec/1272c19:dd:d9:dd:c25:c25:d00a:feed
1202c19:dd:d9:dd:c25:c25:d00a:feee/1272c19:dd:d9:dd:c25:c25:d00a:feef
1212c19:dd:d9:dd:c25:c25:d00a:fef0/1272c19:dd:d9:dd:c25:c25:d00a:fef1
1222c19:dd:d9:dd:c25:c25:d00a:fef2/1272c19:dd:d9:dd:c25:c25:d00a:fef3
1232c19:dd:d9:dd:c25:c25:d00a:fef4/1272c19:dd:d9:dd:c25:c25:d00a:fef5
1242c19:dd:d9:dd:c25:c25:d00a:fef6/1272c19:dd:d9:dd:c25:c25:d00a:fef7
1252c19:dd:d9:dd:c25:c25:d00a:fef8/1272c19:dd:d9:dd:c25:c25:d00a:fef9
1262c19:dd:d9:dd:c25:c25:d00a:fefa/1272c19:dd:d9:dd:c25:c25:d00a:fefb
1272c19:dd:d9:dd:c25:c25:d00a:fefc/1272c19:dd:d9:dd:c25:c25:d00a:fefd
1282c19:dd:d9:dd:c25:c25:d00a:fefe/1272c19:dd:d9:dd:c25:c25:d00a:feff
1292c19:dd:d9:dd:c25:c25:d00a:ff00/1272c19:dd:d9:dd:c25:c25:d00a:ff01
1302c19:dd:d9:dd:c25:c25:d00a:ff02/1272c19:dd:d9:dd:c25:c25:d00a:ff03
1312c19:dd:d9:dd:c25:c25:d00a:ff04/1272c19:dd:d9:dd:c25:c25:d00a:ff05
1322c19:dd:d9:dd:c25:c25:d00a:ff06/1272c19:dd:d9:dd:c25:c25:d00a:ff07
1332c19:dd:d9:dd:c25:c25:d00a:ff08/1272c19:dd:d9:dd:c25:c25:d00a:ff09
1342c19:dd:d9:dd:c25:c25:d00a:ff0a/1272c19:dd:d9:dd:c25:c25:d00a:ff0b
1352c19:dd:d9:dd:c25:c25:d00a:ff0c/1272c19:dd:d9:dd:c25:c25:d00a:ff0d
1362c19:dd:d9:dd:c25:c25:d00a:ff0e/1272c19:dd:d9:dd:c25:c25:d00a:ff0f
1372c19:dd:d9:dd:c25:c25:d00a:ff10/1272c19:dd:d9:dd:c25:c25:d00a:ff11
1382c19:dd:d9:dd:c25:c25:d00a:ff12/1272c19:dd:d9:dd:c25:c25:d00a:ff13
1392c19:dd:d9:dd:c25:c25:d00a:ff14/1272c19:dd:d9:dd:c25:c25:d00a:ff15
1402c19:dd:d9:dd:c25:c25:d00a:ff16/1272c19:dd:d9:dd:c25:c25:d00a:ff17
1412c19:dd:d9:dd:c25:c25:d00a:ff18/1272c19:dd:d9:dd:c25:c25:d00a:ff19
1422c19:dd:d9:dd:c25:c25:d00a:ff1a/1272c19:dd:d9:dd:c25:c25:d00a:ff1b
1432c19:dd:d9:dd:c25:c25:d00a:ff1c/1272c19:dd:d9:dd:c25:c25:d00a:ff1d
1442c19:dd:d9:dd:c25:c25:d00a:ff1e/1272c19:dd:d9:dd:c25:c25:d00a:ff1f
1452c19:dd:d9:dd:c25:c25:d00a:ff20/1272c19:dd:d9:dd:c25:c25:d00a:ff21
1462c19:dd:d9:dd:c25:c25:d00a:ff22/1272c19:dd:d9:dd:c25:c25:d00a:ff23
1472c19:dd:d9:dd:c25:c25:d00a:ff24/1272c19:dd:d9:dd:c25:c25:d00a:ff25
1482c19:dd:d9:dd:c25:c25:d00a:ff26/1272c19:dd:d9:dd:c25:c25:d00a:ff27
1492c19:dd:d9:dd:c25:c25:d00a:ff28/1272c19:dd:d9:dd:c25:c25:d00a:ff29
1502c19:dd:d9:dd:c25:c25:d00a:ff2a/1272c19:dd:d9:dd:c25:c25:d00a:ff2b
1512c19:dd:d9:dd:c25:c25:d00a:ff2c/1272c19:dd:d9:dd:c25:c25:d00a:ff2d
1522c19:dd:d9:dd:c25:c25:d00a:ff2e/1272c19:dd:d9:dd:c25:c25:d00a:ff2f
1532c19:dd:d9:dd:c25:c25:d00a:ff30/1272c19:dd:d9:dd:c25:c25:d00a:ff31
1542c19:dd:d9:dd:c25:c25:d00a:ff32/1272c19:dd:d9:dd:c25:c25:d00a:ff33
1552c19:dd:d9:dd:c25:c25:d00a:ff34/1272c19:dd:d9:dd:c25:c25:d00a:ff35
1562c19:dd:d9:dd:c25:c25:d00a:ff36/1272c19:dd:d9:dd:c25:c25:d00a:ff37
1572c19:dd:d9:dd:c25:c25:d00a:ff38/1272c19:dd:d9:dd:c25:c25:d00a:ff39
1582c19:dd:d9:dd:c25:c25:d00a:ff3a/1272c19:dd:d9:dd:c25:c25:d00a:ff3b
1592c19:dd:d9:dd:c25:c25:d00a:ff3c/1272c19:dd:d9:dd:c25:c25:d00a:ff3d
1602c19:dd:d9:dd:c25:c25:d00a:ff3e/1272c19:dd:d9:dd:c25:c25:d00a:ff3f
1612c19:dd:d9:dd:c25:c25:d00a:ff40/1272c19:dd:d9:dd:c25:c25:d00a:ff41
1622c19:dd:d9:dd:c25:c25:d00a:ff42/1272c19:dd:d9:dd:c25:c25:d00a:ff43
1632c19:dd:d9:dd:c25:c25:d00a:ff44/1272c19:dd:d9:dd:c25:c25:d00a:ff45
1642c19:dd:d9:dd:c25:c25:d00a:ff46/1272c19:dd:d9:dd:c25:c25:d00a:ff47
1652c19:dd:d9:dd:c25:c25:d00a:ff48/1272c19:dd:d9:dd:c25:c25:d00a:ff49
1662c19:dd:d9:dd:c25:c25:d00a:ff4a/1272c19:dd:d9:dd:c25:c25:d00a:ff4b
1672c19:dd:d9:dd:c25:c25:d00a:ff4c/1272c19:dd:d9:dd:c25:c25:d00a:ff4d
1682c19:dd:d9:dd:c25:c25:d00a:ff4e/1272c19:dd:d9:dd:c25:c25:d00a:ff4f
1692c19:dd:d9:dd:c25:c25:d00a:ff50/1272c19:dd:d9:dd:c25:c25:d00a:ff51
1702c19:dd:d9:dd:c25:c25:d00a:ff52/1272c19:dd:d9:dd:c25:c25:d00a:ff53
1712c19:dd:d9:dd:c25:c25:d00a:ff54/1272c19:dd:d9:dd:c25:c25:d00a:ff55
1722c19:dd:d9:dd:c25:c25:d00a:ff56/1272c19:dd:d9:dd:c25:c25:d00a:ff57
1732c19:dd:d9:dd:c25:c25:d00a:ff58/1272c19:dd:d9:dd:c25:c25:d00a:ff59
1742c19:dd:d9:dd:c25:c25:d00a:ff5a/1272c19:dd:d9:dd:c25:c25:d00a:ff5b
1752c19:dd:d9:dd:c25:c25:d00a:ff5c/1272c19:dd:d9:dd:c25:c25:d00a:ff5d
1762c19:dd:d9:dd:c25:c25:d00a:ff5e/1272c19:dd:d9:dd:c25:c25:d00a:ff5f
1772c19:dd:d9:dd:c25:c25:d00a:ff60/1272c19:dd:d9:dd:c25:c25:d00a:ff61
1782c19:dd:d9:dd:c25:c25:d00a:ff62/1272c19:dd:d9:dd:c25:c25:d00a:ff63
1792c19:dd:d9:dd:c25:c25:d00a:ff64/1272c19:dd:d9:dd:c25:c25:d00a:ff65
1802c19:dd:d9:dd:c25:c25:d00a:ff66/1272c19:dd:d9:dd:c25:c25:d00a:ff67
1812c19:dd:d9:dd:c25:c25:d00a:ff68/1272c19:dd:d9:dd:c25:c25:d00a:ff69
1822c19:dd:d9:dd:c25:c25:d00a:ff6a/1272c19:dd:d9:dd:c25:c25:d00a:ff6b
1832c19:dd:d9:dd:c25:c25:d00a:ff6c/1272c19:dd:d9:dd:c25:c25:d00a:ff6d
1842c19:dd:d9:dd:c25:c25:d00a:ff6e/1272c19:dd:d9:dd:c25:c25:d00a:ff6f
1852c19:dd:d9:dd:c25:c25:d00a:ff70/1272c19:dd:d9:dd:c25:c25:d00a:ff71
1862c19:dd:d9:dd:c25:c25:d00a:ff72/1272c19:dd:d9:dd:c25:c25:d00a:ff73
1872c19:dd:d9:dd:c25:c25:d00a:ff74/1272c19:dd:d9:dd:c25:c25:d00a:ff75
1882c19:dd:d9:dd:c25:c25:d00a:ff76/1272c19:dd:d9:dd:c25:c25:d00a:ff77
1892c19:dd:d9:dd:c25:c25:d00a:ff78/1272c19:dd:d9:dd:c25:c25:d00a:ff79
1902c19:dd:d9:dd:c25:c25:d00a:ff7a/1272c19:dd:d9:dd:c25:c25:d00a:ff7b
1912c19:dd:d9:dd:c25:c25:d00a:ff7c/1272c19:dd:d9:dd:c25:c25:d00a:ff7d
1922c19:dd:d9:dd:c25:c25:d00a:ff7e/1272c19:dd:d9:dd:c25:c25:d00a:ff7f
1932c19:dd:d9:dd:c25:c25:d00a:ff80/1272c19:dd:d9:dd:c25:c25:d00a:ff81
1942c19:dd:d9:dd:c25:c25:d00a:ff82/1272c19:dd:d9:dd:c25:c25:d00a:ff83
1952c19:dd:d9:dd:c25:c25:d00a:ff84/1272c19:dd:d9:dd:c25:c25:d00a:ff85
1962c19:dd:d9:dd:c25:c25:d00a:ff86/1272c19:dd:d9:dd:c25:c25:d00a:ff87
1972c19:dd:d9:dd:c25:c25:d00a:ff88/1272c19:dd:d9:dd:c25:c25:d00a:ff89
1982c19:dd:d9:dd:c25:c25:d00a:ff8a/1272c19:dd:d9:dd:c25:c25:d00a:ff8b
1992c19:dd:d9:dd:c25:c25:d00a:ff8c/1272c19:dd:d9:dd:c25:c25:d00a:ff8d
2002c19:dd:d9:dd:c25:c25:d00a:ff8e/1272c19:dd:d9:dd:c25:c25:d00a:ff8f
2012c19:dd:d9:dd:c25:c25:d00a:ff90/1272c19:dd:d9:dd:c25:c25:d00a:ff91
2022c19:dd:d9:dd:c25:c25:d00a:ff92/1272c19:dd:d9:dd:c25:c25:d00a:ff93
2032c19:dd:d9:dd:c25:c25:d00a:ff94/1272c19:dd:d9:dd:c25:c25:d00a:ff95
2042c19:dd:d9:dd:c25:c25:d00a:ff96/1272c19:dd:d9:dd:c25:c25:d00a:ff97
2052c19:dd:d9:dd:c25:c25:d00a:ff98/1272c19:dd:d9:dd:c25:c25:d00a:ff99
2062c19:dd:d9:dd:c25:c25:d00a:ff9a/1272c19:dd:d9:dd:c25:c25:d00a:ff9b
2072c19:dd:d9:dd:c25:c25:d00a:ff9c/1272c19:dd:d9:dd:c25:c25:d00a:ff9d
2082c19:dd:d9:dd:c25:c25:d00a:ff9e/1272c19:dd:d9:dd:c25:c25:d00a:ff9f
2092c19:dd:d9:dd:c25:c25:d00a:ffa0/1272c19:dd:d9:dd:c25:c25:d00a:ffa1
2102c19:dd:d9:dd:c25:c25:d00a:ffa2/1272c19:dd:d9:dd:c25:c25:d00a:ffa3
2112c19:dd:d9:dd:c25:c25:d00a:ffa4/1272c19:dd:d9:dd:c25:c25:d00a:ffa5
2122c19:dd:d9:dd:c25:c25:d00a:ffa6/1272c19:dd:d9:dd:c25:c25:d00a:ffa7
2132c19:dd:d9:dd:c25:c25:d00a:ffa8/1272c19:dd:d9:dd:c25:c25:d00a:ffa9
2142c19:dd:d9:dd:c25:c25:d00a:ffaa/1272c19:dd:d9:dd:c25:c25:d00a:ffab
2152c19:dd:d9:dd:c25:c25:d00a:ffac/1272c19:dd:d9:dd:c25:c25:d00a:ffad
2162c19:dd:d9:dd:c25:c25:d00a:ffae/1272c19:dd:d9:dd:c25:c25:d00a:ffaf
2172c19:dd:d9:dd:c25:c25:d00a:ffb0/1272c19:dd:d9:dd:c25:c25:d00a:ffb1
2182c19:dd:d9:dd:c25:c25:d00a:ffb2/1272c19:dd:d9:dd:c25:c25:d00a:ffb3
2192c19:dd:d9:dd:c25:c25:d00a:ffb4/1272c19:dd:d9:dd:c25:c25:d00a:ffb5
2202c19:dd:d9:dd:c25:c25:d00a:ffb6/1272c19:dd:d9:dd:c25:c25:d00a:ffb7
2212c19:dd:d9:dd:c25:c25:d00a:ffb8/1272c19:dd:d9:dd:c25:c25:d00a:ffb9
2222c19:dd:d9:dd:c25:c25:d00a:ffba/1272c19:dd:d9:dd:c25:c25:d00a:ffbb
2232c19:dd:d9:dd:c25:c25:d00a:ffbc/1272c19:dd:d9:dd:c25:c25:d00a:ffbd
2242c19:dd:d9:dd:c25:c25:d00a:ffbe/1272c19:dd:d9:dd:c25:c25:d00a:ffbf
2252c19:dd:d9:dd:c25:c25:d00a:ffc0/1272c19:dd:d9:dd:c25:c25:d00a:ffc1
2262c19:dd:d9:dd:c25:c25:d00a:ffc2/1272c19:dd:d9:dd:c25:c25:d00a:ffc3
2272c19:dd:d9:dd:c25:c25:d00a:ffc4/1272c19:dd:d9:dd:c25:c25:d00a:ffc5
2282c19:dd:d9:dd:c25:c25:d00a:ffc6/1272c19:dd:d9:dd:c25:c25:d00a:ffc7
2292c19:dd:d9:dd:c25:c25:d00a:ffc8/1272c19:dd:d9:dd:c25:c25:d00a:ffc9
2302c19:dd:d9:dd:c25:c25:d00a:ffca/1272c19:dd:d9:dd:c25:c25:d00a:ffcb
2312c19:dd:d9:dd:c25:c25:d00a:ffcc/1272c19:dd:d9:dd:c25:c25:d00a:ffcd
2322c19:dd:d9:dd:c25:c25:d00a:ffce/1272c19:dd:d9:dd:c25:c25:d00a:ffcf
2332c19:dd:d9:dd:c25:c25:d00a:ffd0/1272c19:dd:d9:dd:c25:c25:d00a:ffd1
2342c19:dd:d9:dd:c25:c25:d00a:ffd2/1272c19:dd:d9:dd:c25:c25:d00a:ffd3
2352c19:dd:d9:dd:c25:c25:d00a:ffd4/1272c19:dd:d9:dd:c25:c25:d00a:ffd5
2362c19:dd:d9:dd:c25:c25:d00a:ffd6/1272c19:dd:d9:dd:c25:c25:d00a:ffd7
2372c19:dd:d9:dd:c25:c25:d00a:ffd8/1272c19:dd:d9:dd:c25:c25:d00a:ffd9
2382c19:dd:d9:dd:c25:c25:d00a:ffda/1272c19:dd:d9:dd:c25:c25:d00a:ffdb
2392c19:dd:d9:dd:c25:c25:d00a:ffdc/1272c19:dd:d9:dd:c25:c25:d00a:ffdd
2402c19:dd:d9:dd:c25:c25:d00a:ffde/1272c19:dd:d9:dd:c25:c25:d00a:ffdf
2412c19:dd:d9:dd:c25:c25:d00a:ffe0/1272c19:dd:d9:dd:c25:c25:d00a:ffe1
2422c19:dd:d9:dd:c25:c25:d00a:ffe2/1272c19:dd:d9:dd:c25:c25:d00a:ffe3
2432c19:dd:d9:dd:c25:c25:d00a:ffe4/1272c19:dd:d9:dd:c25:c25:d00a:ffe5
2442c19:dd:d9:dd:c25:c25:d00a:ffe6/1272c19:dd:d9:dd:c25:c25:d00a:ffe7
2452c19:dd:d9:dd:c25:c25:d00a:ffe8/1272c19:dd:d9:dd:c25:c25:d00a:ffe9
2462c19:dd:d9:dd:c25:c25:d00a:ffea/1272c19:dd:d9:dd:c25:c25:d00a:ffeb
2472c19:dd:d9:dd:c25:c25:d00a:ffec/1272c19:dd:d9:dd:c25:c25:d00a:ffed
2482c19:dd:d9:dd:c25:c25:d00a:ffee/1272c19:dd:d9:dd:c25:c25:d00a:ffef
2492c19:dd:d9:dd:c25:c25:d00a:fff0/1272c19:dd:d9:dd:c25:c25:d00a:fff1
2502c19:dd:d9:dd:c25:c25:d00a:fff2/1272c19:dd:d9:dd:c25:c25:d00a:fff3
2512c19:dd:d9:dd:c25:c25:d00a:fff4/1272c19:dd:d9:dd:c25:c25:d00a:fff5
2522c19:dd:d9:dd:c25:c25:d00a:fff6/1272c19:dd:d9:dd:c25:c25:d00a:fff7
2532c19:dd:d9:dd:c25:c25:d00a:fff8/1272c19:dd:d9:dd:c25:c25:d00a:fff9
2542c19:dd:d9:dd:c25:c25:d00a:fffa/1272c19:dd:d9:dd:c25:c25:d00a:fffb
2552c19:dd:d9:dd:c25:c25:d00a:fffc/1272c19:dd:d9:dd:c25:c25:d00a:fffd
2562c19:dd:d9:dd:c25:c25:d00a:fffe/1272c19:dd:d9:dd:c25:c25:d00a:ffff

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.