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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Prefix/119
Addresses512
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:d915:c00/119
First address
2c19:dd:d9:dd:c25:c25:d915:c00
Last address
2c19:dd:d9:dd:c25:c25:d915:dff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:d915:0c00
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
c.0.5.1.9.d.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
d.0.5.1.9.d.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/127
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:d915:c00/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:d915:c00/1272c19:dd:d9:dd:c25:c25:d915:c01
22c19:dd:d9:dd:c25:c25:d915:c02/1272c19:dd:d9:dd:c25:c25:d915:c03
32c19:dd:d9:dd:c25:c25:d915:c04/1272c19:dd:d9:dd:c25:c25:d915:c05
42c19:dd:d9:dd:c25:c25:d915:c06/1272c19:dd:d9:dd:c25:c25:d915:c07
52c19:dd:d9:dd:c25:c25:d915:c08/1272c19:dd:d9:dd:c25:c25:d915:c09
62c19:dd:d9:dd:c25:c25:d915:c0a/1272c19:dd:d9:dd:c25:c25:d915:c0b
72c19:dd:d9:dd:c25:c25:d915:c0c/1272c19:dd:d9:dd:c25:c25:d915:c0d
82c19:dd:d9:dd:c25:c25:d915:c0e/1272c19:dd:d9:dd:c25:c25:d915:c0f
92c19:dd:d9:dd:c25:c25:d915:c10/1272c19:dd:d9:dd:c25:c25:d915:c11
102c19:dd:d9:dd:c25:c25:d915:c12/1272c19:dd:d9:dd:c25:c25:d915:c13
112c19:dd:d9:dd:c25:c25:d915:c14/1272c19:dd:d9:dd:c25:c25:d915:c15
122c19:dd:d9:dd:c25:c25:d915:c16/1272c19:dd:d9:dd:c25:c25:d915:c17
132c19:dd:d9:dd:c25:c25:d915:c18/1272c19:dd:d9:dd:c25:c25:d915:c19
142c19:dd:d9:dd:c25:c25:d915:c1a/1272c19:dd:d9:dd:c25:c25:d915:c1b
152c19:dd:d9:dd:c25:c25:d915:c1c/1272c19:dd:d9:dd:c25:c25:d915:c1d
162c19:dd:d9:dd:c25:c25:d915:c1e/1272c19:dd:d9:dd:c25:c25:d915:c1f
172c19:dd:d9:dd:c25:c25:d915:c20/1272c19:dd:d9:dd:c25:c25:d915:c21
182c19:dd:d9:dd:c25:c25:d915:c22/1272c19:dd:d9:dd:c25:c25:d915:c23
192c19:dd:d9:dd:c25:c25:d915:c24/1272c19:dd:d9:dd:c25:c25:d915:c25
202c19:dd:d9:dd:c25:c25:d915:c26/1272c19:dd:d9:dd:c25:c25:d915:c27
212c19:dd:d9:dd:c25:c25:d915:c28/1272c19:dd:d9:dd:c25:c25:d915:c29
222c19:dd:d9:dd:c25:c25:d915:c2a/1272c19:dd:d9:dd:c25:c25:d915:c2b
232c19:dd:d9:dd:c25:c25:d915:c2c/1272c19:dd:d9:dd:c25:c25:d915:c2d
242c19:dd:d9:dd:c25:c25:d915:c2e/1272c19:dd:d9:dd:c25:c25:d915:c2f
252c19:dd:d9:dd:c25:c25:d915:c30/1272c19:dd:d9:dd:c25:c25:d915:c31
262c19:dd:d9:dd:c25:c25:d915:c32/1272c19:dd:d9:dd:c25:c25:d915:c33
272c19:dd:d9:dd:c25:c25:d915:c34/1272c19:dd:d9:dd:c25:c25:d915:c35
282c19:dd:d9:dd:c25:c25:d915:c36/1272c19:dd:d9:dd:c25:c25:d915:c37
292c19:dd:d9:dd:c25:c25:d915:c38/1272c19:dd:d9:dd:c25:c25:d915:c39
302c19:dd:d9:dd:c25:c25:d915:c3a/1272c19:dd:d9:dd:c25:c25:d915:c3b
312c19:dd:d9:dd:c25:c25:d915:c3c/1272c19:dd:d9:dd:c25:c25:d915:c3d
322c19:dd:d9:dd:c25:c25:d915:c3e/1272c19:dd:d9:dd:c25:c25:d915:c3f
332c19:dd:d9:dd:c25:c25:d915:c40/1272c19:dd:d9:dd:c25:c25:d915:c41
342c19:dd:d9:dd:c25:c25:d915:c42/1272c19:dd:d9:dd:c25:c25:d915:c43
352c19:dd:d9:dd:c25:c25:d915:c44/1272c19:dd:d9:dd:c25:c25:d915:c45
362c19:dd:d9:dd:c25:c25:d915:c46/1272c19:dd:d9:dd:c25:c25:d915:c47
372c19:dd:d9:dd:c25:c25:d915:c48/1272c19:dd:d9:dd:c25:c25:d915:c49
382c19:dd:d9:dd:c25:c25:d915:c4a/1272c19:dd:d9:dd:c25:c25:d915:c4b
392c19:dd:d9:dd:c25:c25:d915:c4c/1272c19:dd:d9:dd:c25:c25:d915:c4d
402c19:dd:d9:dd:c25:c25:d915:c4e/1272c19:dd:d9:dd:c25:c25:d915:c4f
412c19:dd:d9:dd:c25:c25:d915:c50/1272c19:dd:d9:dd:c25:c25:d915:c51
422c19:dd:d9:dd:c25:c25:d915:c52/1272c19:dd:d9:dd:c25:c25:d915:c53
432c19:dd:d9:dd:c25:c25:d915:c54/1272c19:dd:d9:dd:c25:c25:d915:c55
442c19:dd:d9:dd:c25:c25:d915:c56/1272c19:dd:d9:dd:c25:c25:d915:c57
452c19:dd:d9:dd:c25:c25:d915:c58/1272c19:dd:d9:dd:c25:c25:d915:c59
462c19:dd:d9:dd:c25:c25:d915:c5a/1272c19:dd:d9:dd:c25:c25:d915:c5b
472c19:dd:d9:dd:c25:c25:d915:c5c/1272c19:dd:d9:dd:c25:c25:d915:c5d
482c19:dd:d9:dd:c25:c25:d915:c5e/1272c19:dd:d9:dd:c25:c25:d915:c5f
492c19:dd:d9:dd:c25:c25:d915:c60/1272c19:dd:d9:dd:c25:c25:d915:c61
502c19:dd:d9:dd:c25:c25:d915:c62/1272c19:dd:d9:dd:c25:c25:d915:c63
512c19:dd:d9:dd:c25:c25:d915:c64/1272c19:dd:d9:dd:c25:c25:d915:c65
522c19:dd:d9:dd:c25:c25:d915:c66/1272c19:dd:d9:dd:c25:c25:d915:c67
532c19:dd:d9:dd:c25:c25:d915:c68/1272c19:dd:d9:dd:c25:c25:d915:c69
542c19:dd:d9:dd:c25:c25:d915:c6a/1272c19:dd:d9:dd:c25:c25:d915:c6b
552c19:dd:d9:dd:c25:c25:d915:c6c/1272c19:dd:d9:dd:c25:c25:d915:c6d
562c19:dd:d9:dd:c25:c25:d915:c6e/1272c19:dd:d9:dd:c25:c25:d915:c6f
572c19:dd:d9:dd:c25:c25:d915:c70/1272c19:dd:d9:dd:c25:c25:d915:c71
582c19:dd:d9:dd:c25:c25:d915:c72/1272c19:dd:d9:dd:c25:c25:d915:c73
592c19:dd:d9:dd:c25:c25:d915:c74/1272c19:dd:d9:dd:c25:c25:d915:c75
602c19:dd:d9:dd:c25:c25:d915:c76/1272c19:dd:d9:dd:c25:c25:d915:c77
612c19:dd:d9:dd:c25:c25:d915:c78/1272c19:dd:d9:dd:c25:c25:d915:c79
622c19:dd:d9:dd:c25:c25:d915:c7a/1272c19:dd:d9:dd:c25:c25:d915:c7b
632c19:dd:d9:dd:c25:c25:d915:c7c/1272c19:dd:d9:dd:c25:c25:d915:c7d
642c19:dd:d9:dd:c25:c25:d915:c7e/1272c19:dd:d9:dd:c25:c25:d915:c7f
652c19:dd:d9:dd:c25:c25:d915:c80/1272c19:dd:d9:dd:c25:c25:d915:c81
662c19:dd:d9:dd:c25:c25:d915:c82/1272c19:dd:d9:dd:c25:c25:d915:c83
672c19:dd:d9:dd:c25:c25:d915:c84/1272c19:dd:d9:dd:c25:c25:d915:c85
682c19:dd:d9:dd:c25:c25:d915:c86/1272c19:dd:d9:dd:c25:c25:d915:c87
692c19:dd:d9:dd:c25:c25:d915:c88/1272c19:dd:d9:dd:c25:c25:d915:c89
702c19:dd:d9:dd:c25:c25:d915:c8a/1272c19:dd:d9:dd:c25:c25:d915:c8b
712c19:dd:d9:dd:c25:c25:d915:c8c/1272c19:dd:d9:dd:c25:c25:d915:c8d
722c19:dd:d9:dd:c25:c25:d915:c8e/1272c19:dd:d9:dd:c25:c25:d915:c8f
732c19:dd:d9:dd:c25:c25:d915:c90/1272c19:dd:d9:dd:c25:c25:d915:c91
742c19:dd:d9:dd:c25:c25:d915:c92/1272c19:dd:d9:dd:c25:c25:d915:c93
752c19:dd:d9:dd:c25:c25:d915:c94/1272c19:dd:d9:dd:c25:c25:d915:c95
762c19:dd:d9:dd:c25:c25:d915:c96/1272c19:dd:d9:dd:c25:c25:d915:c97
772c19:dd:d9:dd:c25:c25:d915:c98/1272c19:dd:d9:dd:c25:c25:d915:c99
782c19:dd:d9:dd:c25:c25:d915:c9a/1272c19:dd:d9:dd:c25:c25:d915:c9b
792c19:dd:d9:dd:c25:c25:d915:c9c/1272c19:dd:d9:dd:c25:c25:d915:c9d
802c19:dd:d9:dd:c25:c25:d915:c9e/1272c19:dd:d9:dd:c25:c25:d915:c9f
812c19:dd:d9:dd:c25:c25:d915:ca0/1272c19:dd:d9:dd:c25:c25:d915:ca1
822c19:dd:d9:dd:c25:c25:d915:ca2/1272c19:dd:d9:dd:c25:c25:d915:ca3
832c19:dd:d9:dd:c25:c25:d915:ca4/1272c19:dd:d9:dd:c25:c25:d915:ca5
842c19:dd:d9:dd:c25:c25:d915:ca6/1272c19:dd:d9:dd:c25:c25:d915:ca7
852c19:dd:d9:dd:c25:c25:d915:ca8/1272c19:dd:d9:dd:c25:c25:d915:ca9
862c19:dd:d9:dd:c25:c25:d915:caa/1272c19:dd:d9:dd:c25:c25:d915:cab
872c19:dd:d9:dd:c25:c25:d915:cac/1272c19:dd:d9:dd:c25:c25:d915:cad
882c19:dd:d9:dd:c25:c25:d915:cae/1272c19:dd:d9:dd:c25:c25:d915:caf
892c19:dd:d9:dd:c25:c25:d915:cb0/1272c19:dd:d9:dd:c25:c25:d915:cb1
902c19:dd:d9:dd:c25:c25:d915:cb2/1272c19:dd:d9:dd:c25:c25:d915:cb3
912c19:dd:d9:dd:c25:c25:d915:cb4/1272c19:dd:d9:dd:c25:c25:d915:cb5
922c19:dd:d9:dd:c25:c25:d915:cb6/1272c19:dd:d9:dd:c25:c25:d915:cb7
932c19:dd:d9:dd:c25:c25:d915:cb8/1272c19:dd:d9:dd:c25:c25:d915:cb9
942c19:dd:d9:dd:c25:c25:d915:cba/1272c19:dd:d9:dd:c25:c25:d915:cbb
952c19:dd:d9:dd:c25:c25:d915:cbc/1272c19:dd:d9:dd:c25:c25:d915:cbd
962c19:dd:d9:dd:c25:c25:d915:cbe/1272c19:dd:d9:dd:c25:c25:d915:cbf
972c19:dd:d9:dd:c25:c25:d915:cc0/1272c19:dd:d9:dd:c25:c25:d915:cc1
982c19:dd:d9:dd:c25:c25:d915:cc2/1272c19:dd:d9:dd:c25:c25:d915:cc3
992c19:dd:d9:dd:c25:c25:d915:cc4/1272c19:dd:d9:dd:c25:c25:d915:cc5
1002c19:dd:d9:dd:c25:c25:d915:cc6/1272c19:dd:d9:dd:c25:c25:d915:cc7
1012c19:dd:d9:dd:c25:c25:d915:cc8/1272c19:dd:d9:dd:c25:c25:d915:cc9
1022c19:dd:d9:dd:c25:c25:d915:cca/1272c19:dd:d9:dd:c25:c25:d915:ccb
1032c19:dd:d9:dd:c25:c25:d915:ccc/1272c19:dd:d9:dd:c25:c25:d915:ccd
1042c19:dd:d9:dd:c25:c25:d915:cce/1272c19:dd:d9:dd:c25:c25:d915:ccf
1052c19:dd:d9:dd:c25:c25:d915:cd0/1272c19:dd:d9:dd:c25:c25:d915:cd1
1062c19:dd:d9:dd:c25:c25:d915:cd2/1272c19:dd:d9:dd:c25:c25:d915:cd3
1072c19:dd:d9:dd:c25:c25:d915:cd4/1272c19:dd:d9:dd:c25:c25:d915:cd5
1082c19:dd:d9:dd:c25:c25:d915:cd6/1272c19:dd:d9:dd:c25:c25:d915:cd7
1092c19:dd:d9:dd:c25:c25:d915:cd8/1272c19:dd:d9:dd:c25:c25:d915:cd9
1102c19:dd:d9:dd:c25:c25:d915:cda/1272c19:dd:d9:dd:c25:c25:d915:cdb
1112c19:dd:d9:dd:c25:c25:d915:cdc/1272c19:dd:d9:dd:c25:c25:d915:cdd
1122c19:dd:d9:dd:c25:c25:d915:cde/1272c19:dd:d9:dd:c25:c25:d915:cdf
1132c19:dd:d9:dd:c25:c25:d915:ce0/1272c19:dd:d9:dd:c25:c25:d915:ce1
1142c19:dd:d9:dd:c25:c25:d915:ce2/1272c19:dd:d9:dd:c25:c25:d915:ce3
1152c19:dd:d9:dd:c25:c25:d915:ce4/1272c19:dd:d9:dd:c25:c25:d915:ce5
1162c19:dd:d9:dd:c25:c25:d915:ce6/1272c19:dd:d9:dd:c25:c25:d915:ce7
1172c19:dd:d9:dd:c25:c25:d915:ce8/1272c19:dd:d9:dd:c25:c25:d915:ce9
1182c19:dd:d9:dd:c25:c25:d915:cea/1272c19:dd:d9:dd:c25:c25:d915:ceb
1192c19:dd:d9:dd:c25:c25:d915:cec/1272c19:dd:d9:dd:c25:c25:d915:ced
1202c19:dd:d9:dd:c25:c25:d915:cee/1272c19:dd:d9:dd:c25:c25:d915:cef
1212c19:dd:d9:dd:c25:c25:d915:cf0/1272c19:dd:d9:dd:c25:c25:d915:cf1
1222c19:dd:d9:dd:c25:c25:d915:cf2/1272c19:dd:d9:dd:c25:c25:d915:cf3
1232c19:dd:d9:dd:c25:c25:d915:cf4/1272c19:dd:d9:dd:c25:c25:d915:cf5
1242c19:dd:d9:dd:c25:c25:d915:cf6/1272c19:dd:d9:dd:c25:c25:d915:cf7
1252c19:dd:d9:dd:c25:c25:d915:cf8/1272c19:dd:d9:dd:c25:c25:d915:cf9
1262c19:dd:d9:dd:c25:c25:d915:cfa/1272c19:dd:d9:dd:c25:c25:d915:cfb
1272c19:dd:d9:dd:c25:c25:d915:cfc/1272c19:dd:d9:dd:c25:c25:d915:cfd
1282c19:dd:d9:dd:c25:c25:d915:cfe/1272c19:dd:d9:dd:c25:c25:d915:cff
1292c19:dd:d9:dd:c25:c25:d915:d00/1272c19:dd:d9:dd:c25:c25:d915:d01
1302c19:dd:d9:dd:c25:c25:d915:d02/1272c19:dd:d9:dd:c25:c25:d915:d03
1312c19:dd:d9:dd:c25:c25:d915:d04/1272c19:dd:d9:dd:c25:c25:d915:d05
1322c19:dd:d9:dd:c25:c25:d915:d06/1272c19:dd:d9:dd:c25:c25:d915:d07
1332c19:dd:d9:dd:c25:c25:d915:d08/1272c19:dd:d9:dd:c25:c25:d915:d09
1342c19:dd:d9:dd:c25:c25:d915:d0a/1272c19:dd:d9:dd:c25:c25:d915:d0b
1352c19:dd:d9:dd:c25:c25:d915:d0c/1272c19:dd:d9:dd:c25:c25:d915:d0d
1362c19:dd:d9:dd:c25:c25:d915:d0e/1272c19:dd:d9:dd:c25:c25:d915:d0f
1372c19:dd:d9:dd:c25:c25:d915:d10/1272c19:dd:d9:dd:c25:c25:d915:d11
1382c19:dd:d9:dd:c25:c25:d915:d12/1272c19:dd:d9:dd:c25:c25:d915:d13
1392c19:dd:d9:dd:c25:c25:d915:d14/1272c19:dd:d9:dd:c25:c25:d915:d15
1402c19:dd:d9:dd:c25:c25:d915:d16/1272c19:dd:d9:dd:c25:c25:d915:d17
1412c19:dd:d9:dd:c25:c25:d915:d18/1272c19:dd:d9:dd:c25:c25:d915:d19
1422c19:dd:d9:dd:c25:c25:d915:d1a/1272c19:dd:d9:dd:c25:c25:d915:d1b
1432c19:dd:d9:dd:c25:c25:d915:d1c/1272c19:dd:d9:dd:c25:c25:d915:d1d
1442c19:dd:d9:dd:c25:c25:d915:d1e/1272c19:dd:d9:dd:c25:c25:d915:d1f
1452c19:dd:d9:dd:c25:c25:d915:d20/1272c19:dd:d9:dd:c25:c25:d915:d21
1462c19:dd:d9:dd:c25:c25:d915:d22/1272c19:dd:d9:dd:c25:c25:d915:d23
1472c19:dd:d9:dd:c25:c25:d915:d24/1272c19:dd:d9:dd:c25:c25:d915:d25
1482c19:dd:d9:dd:c25:c25:d915:d26/1272c19:dd:d9:dd:c25:c25:d915:d27
1492c19:dd:d9:dd:c25:c25:d915:d28/1272c19:dd:d9:dd:c25:c25:d915:d29
1502c19:dd:d9:dd:c25:c25:d915:d2a/1272c19:dd:d9:dd:c25:c25:d915:d2b
1512c19:dd:d9:dd:c25:c25:d915:d2c/1272c19:dd:d9:dd:c25:c25:d915:d2d
1522c19:dd:d9:dd:c25:c25:d915:d2e/1272c19:dd:d9:dd:c25:c25:d915:d2f
1532c19:dd:d9:dd:c25:c25:d915:d30/1272c19:dd:d9:dd:c25:c25:d915:d31
1542c19:dd:d9:dd:c25:c25:d915:d32/1272c19:dd:d9:dd:c25:c25:d915:d33
1552c19:dd:d9:dd:c25:c25:d915:d34/1272c19:dd:d9:dd:c25:c25:d915:d35
1562c19:dd:d9:dd:c25:c25:d915:d36/1272c19:dd:d9:dd:c25:c25:d915:d37
1572c19:dd:d9:dd:c25:c25:d915:d38/1272c19:dd:d9:dd:c25:c25:d915:d39
1582c19:dd:d9:dd:c25:c25:d915:d3a/1272c19:dd:d9:dd:c25:c25:d915:d3b
1592c19:dd:d9:dd:c25:c25:d915:d3c/1272c19:dd:d9:dd:c25:c25:d915:d3d
1602c19:dd:d9:dd:c25:c25:d915:d3e/1272c19:dd:d9:dd:c25:c25:d915:d3f
1612c19:dd:d9:dd:c25:c25:d915:d40/1272c19:dd:d9:dd:c25:c25:d915:d41
1622c19:dd:d9:dd:c25:c25:d915:d42/1272c19:dd:d9:dd:c25:c25:d915:d43
1632c19:dd:d9:dd:c25:c25:d915:d44/1272c19:dd:d9:dd:c25:c25:d915:d45
1642c19:dd:d9:dd:c25:c25:d915:d46/1272c19:dd:d9:dd:c25:c25:d915:d47
1652c19:dd:d9:dd:c25:c25:d915:d48/1272c19:dd:d9:dd:c25:c25:d915:d49
1662c19:dd:d9:dd:c25:c25:d915:d4a/1272c19:dd:d9:dd:c25:c25:d915:d4b
1672c19:dd:d9:dd:c25:c25:d915:d4c/1272c19:dd:d9:dd:c25:c25:d915:d4d
1682c19:dd:d9:dd:c25:c25:d915:d4e/1272c19:dd:d9:dd:c25:c25:d915:d4f
1692c19:dd:d9:dd:c25:c25:d915:d50/1272c19:dd:d9:dd:c25:c25:d915:d51
1702c19:dd:d9:dd:c25:c25:d915:d52/1272c19:dd:d9:dd:c25:c25:d915:d53
1712c19:dd:d9:dd:c25:c25:d915:d54/1272c19:dd:d9:dd:c25:c25:d915:d55
1722c19:dd:d9:dd:c25:c25:d915:d56/1272c19:dd:d9:dd:c25:c25:d915:d57
1732c19:dd:d9:dd:c25:c25:d915:d58/1272c19:dd:d9:dd:c25:c25:d915:d59
1742c19:dd:d9:dd:c25:c25:d915:d5a/1272c19:dd:d9:dd:c25:c25:d915:d5b
1752c19:dd:d9:dd:c25:c25:d915:d5c/1272c19:dd:d9:dd:c25:c25:d915:d5d
1762c19:dd:d9:dd:c25:c25:d915:d5e/1272c19:dd:d9:dd:c25:c25:d915:d5f
1772c19:dd:d9:dd:c25:c25:d915:d60/1272c19:dd:d9:dd:c25:c25:d915:d61
1782c19:dd:d9:dd:c25:c25:d915:d62/1272c19:dd:d9:dd:c25:c25:d915:d63
1792c19:dd:d9:dd:c25:c25:d915:d64/1272c19:dd:d9:dd:c25:c25:d915:d65
1802c19:dd:d9:dd:c25:c25:d915:d66/1272c19:dd:d9:dd:c25:c25:d915:d67
1812c19:dd:d9:dd:c25:c25:d915:d68/1272c19:dd:d9:dd:c25:c25:d915:d69
1822c19:dd:d9:dd:c25:c25:d915:d6a/1272c19:dd:d9:dd:c25:c25:d915:d6b
1832c19:dd:d9:dd:c25:c25:d915:d6c/1272c19:dd:d9:dd:c25:c25:d915:d6d
1842c19:dd:d9:dd:c25:c25:d915:d6e/1272c19:dd:d9:dd:c25:c25:d915:d6f
1852c19:dd:d9:dd:c25:c25:d915:d70/1272c19:dd:d9:dd:c25:c25:d915:d71
1862c19:dd:d9:dd:c25:c25:d915:d72/1272c19:dd:d9:dd:c25:c25:d915:d73
1872c19:dd:d9:dd:c25:c25:d915:d74/1272c19:dd:d9:dd:c25:c25:d915:d75
1882c19:dd:d9:dd:c25:c25:d915:d76/1272c19:dd:d9:dd:c25:c25:d915:d77
1892c19:dd:d9:dd:c25:c25:d915:d78/1272c19:dd:d9:dd:c25:c25:d915:d79
1902c19:dd:d9:dd:c25:c25:d915:d7a/1272c19:dd:d9:dd:c25:c25:d915:d7b
1912c19:dd:d9:dd:c25:c25:d915:d7c/1272c19:dd:d9:dd:c25:c25:d915:d7d
1922c19:dd:d9:dd:c25:c25:d915:d7e/1272c19:dd:d9:dd:c25:c25:d915:d7f
1932c19:dd:d9:dd:c25:c25:d915:d80/1272c19:dd:d9:dd:c25:c25:d915:d81
1942c19:dd:d9:dd:c25:c25:d915:d82/1272c19:dd:d9:dd:c25:c25:d915:d83
1952c19:dd:d9:dd:c25:c25:d915:d84/1272c19:dd:d9:dd:c25:c25:d915:d85
1962c19:dd:d9:dd:c25:c25:d915:d86/1272c19:dd:d9:dd:c25:c25:d915:d87
1972c19:dd:d9:dd:c25:c25:d915:d88/1272c19:dd:d9:dd:c25:c25:d915:d89
1982c19:dd:d9:dd:c25:c25:d915:d8a/1272c19:dd:d9:dd:c25:c25:d915:d8b
1992c19:dd:d9:dd:c25:c25:d915:d8c/1272c19:dd:d9:dd:c25:c25:d915:d8d
2002c19:dd:d9:dd:c25:c25:d915:d8e/1272c19:dd:d9:dd:c25:c25:d915:d8f
2012c19:dd:d9:dd:c25:c25:d915:d90/1272c19:dd:d9:dd:c25:c25:d915:d91
2022c19:dd:d9:dd:c25:c25:d915:d92/1272c19:dd:d9:dd:c25:c25:d915:d93
2032c19:dd:d9:dd:c25:c25:d915:d94/1272c19:dd:d9:dd:c25:c25:d915:d95
2042c19:dd:d9:dd:c25:c25:d915:d96/1272c19:dd:d9:dd:c25:c25:d915:d97
2052c19:dd:d9:dd:c25:c25:d915:d98/1272c19:dd:d9:dd:c25:c25:d915:d99
2062c19:dd:d9:dd:c25:c25:d915:d9a/1272c19:dd:d9:dd:c25:c25:d915:d9b
2072c19:dd:d9:dd:c25:c25:d915:d9c/1272c19:dd:d9:dd:c25:c25:d915:d9d
2082c19:dd:d9:dd:c25:c25:d915:d9e/1272c19:dd:d9:dd:c25:c25:d915:d9f
2092c19:dd:d9:dd:c25:c25:d915:da0/1272c19:dd:d9:dd:c25:c25:d915:da1
2102c19:dd:d9:dd:c25:c25:d915:da2/1272c19:dd:d9:dd:c25:c25:d915:da3
2112c19:dd:d9:dd:c25:c25:d915:da4/1272c19:dd:d9:dd:c25:c25:d915:da5
2122c19:dd:d9:dd:c25:c25:d915:da6/1272c19:dd:d9:dd:c25:c25:d915:da7
2132c19:dd:d9:dd:c25:c25:d915:da8/1272c19:dd:d9:dd:c25:c25:d915:da9
2142c19:dd:d9:dd:c25:c25:d915:daa/1272c19:dd:d9:dd:c25:c25:d915:dab
2152c19:dd:d9:dd:c25:c25:d915:dac/1272c19:dd:d9:dd:c25:c25:d915:dad
2162c19:dd:d9:dd:c25:c25:d915:dae/1272c19:dd:d9:dd:c25:c25:d915:daf
2172c19:dd:d9:dd:c25:c25:d915:db0/1272c19:dd:d9:dd:c25:c25:d915:db1
2182c19:dd:d9:dd:c25:c25:d915:db2/1272c19:dd:d9:dd:c25:c25:d915:db3
2192c19:dd:d9:dd:c25:c25:d915:db4/1272c19:dd:d9:dd:c25:c25:d915:db5
2202c19:dd:d9:dd:c25:c25:d915:db6/1272c19:dd:d9:dd:c25:c25:d915:db7
2212c19:dd:d9:dd:c25:c25:d915:db8/1272c19:dd:d9:dd:c25:c25:d915:db9
2222c19:dd:d9:dd:c25:c25:d915:dba/1272c19:dd:d9:dd:c25:c25:d915:dbb
2232c19:dd:d9:dd:c25:c25:d915:dbc/1272c19:dd:d9:dd:c25:c25:d915:dbd
2242c19:dd:d9:dd:c25:c25:d915:dbe/1272c19:dd:d9:dd:c25:c25:d915:dbf
2252c19:dd:d9:dd:c25:c25:d915:dc0/1272c19:dd:d9:dd:c25:c25:d915:dc1
2262c19:dd:d9:dd:c25:c25:d915:dc2/1272c19:dd:d9:dd:c25:c25:d915:dc3
2272c19:dd:d9:dd:c25:c25:d915:dc4/1272c19:dd:d9:dd:c25:c25:d915:dc5
2282c19:dd:d9:dd:c25:c25:d915:dc6/1272c19:dd:d9:dd:c25:c25:d915:dc7
2292c19:dd:d9:dd:c25:c25:d915:dc8/1272c19:dd:d9:dd:c25:c25:d915:dc9
2302c19:dd:d9:dd:c25:c25:d915:dca/1272c19:dd:d9:dd:c25:c25:d915:dcb
2312c19:dd:d9:dd:c25:c25:d915:dcc/1272c19:dd:d9:dd:c25:c25:d915:dcd
2322c19:dd:d9:dd:c25:c25:d915:dce/1272c19:dd:d9:dd:c25:c25:d915:dcf
2332c19:dd:d9:dd:c25:c25:d915:dd0/1272c19:dd:d9:dd:c25:c25:d915:dd1
2342c19:dd:d9:dd:c25:c25:d915:dd2/1272c19:dd:d9:dd:c25:c25:d915:dd3
2352c19:dd:d9:dd:c25:c25:d915:dd4/1272c19:dd:d9:dd:c25:c25:d915:dd5
2362c19:dd:d9:dd:c25:c25:d915:dd6/1272c19:dd:d9:dd:c25:c25:d915:dd7
2372c19:dd:d9:dd:c25:c25:d915:dd8/1272c19:dd:d9:dd:c25:c25:d915:dd9
2382c19:dd:d9:dd:c25:c25:d915:dda/1272c19:dd:d9:dd:c25:c25:d915:ddb
2392c19:dd:d9:dd:c25:c25:d915:ddc/1272c19:dd:d9:dd:c25:c25:d915:ddd
2402c19:dd:d9:dd:c25:c25:d915:dde/1272c19:dd:d9:dd:c25:c25:d915:ddf
2412c19:dd:d9:dd:c25:c25:d915:de0/1272c19:dd:d9:dd:c25:c25:d915:de1
2422c19:dd:d9:dd:c25:c25:d915:de2/1272c19:dd:d9:dd:c25:c25:d915:de3
2432c19:dd:d9:dd:c25:c25:d915:de4/1272c19:dd:d9:dd:c25:c25:d915:de5
2442c19:dd:d9:dd:c25:c25:d915:de6/1272c19:dd:d9:dd:c25:c25:d915:de7
2452c19:dd:d9:dd:c25:c25:d915:de8/1272c19:dd:d9:dd:c25:c25:d915:de9
2462c19:dd:d9:dd:c25:c25:d915:dea/1272c19:dd:d9:dd:c25:c25:d915:deb
2472c19:dd:d9:dd:c25:c25:d915:dec/1272c19:dd:d9:dd:c25:c25:d915:ded
2482c19:dd:d9:dd:c25:c25:d915:dee/1272c19:dd:d9:dd:c25:c25:d915:def
2492c19:dd:d9:dd:c25:c25:d915:df0/1272c19:dd:d9:dd:c25:c25:d915:df1
2502c19:dd:d9:dd:c25:c25:d915:df2/1272c19:dd:d9:dd:c25:c25:d915:df3
2512c19:dd:d9:dd:c25:c25:d915:df4/1272c19:dd:d9:dd:c25:c25:d915:df5
2522c19:dd:d9:dd:c25:c25:d915:df6/1272c19:dd:d9:dd:c25:c25:d915:df7
2532c19:dd:d9:dd:c25:c25:d915:df8/1272c19:dd:d9:dd:c25:c25:d915:df9
2542c19:dd:d9:dd:c25:c25:d915:dfa/1272c19:dd:d9:dd:c25:c25:d915:dfb
2552c19:dd:d9:dd:c25:c25:d915:dfc/1272c19:dd:d9:dd:c25:c25:d915:dfd
2562c19:dd:d9:dd:c25:c25:d915:dfe/1272c19:dd:d9:dd:c25:c25:d915:dff

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.