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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/32
Addresses2^96
/64 networks2^32
Network
2a67:dd::/32
First address
2a67:dd::
Last address
2a67:dd:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
79,228,162,514,264,337,593,543,950,336 (2^96)
/64 networks (LANs)
4,294,967,296
Full form
2a67:00dd:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
d.d.0.0.7.6.a.2.ip6.arpa
Split into smaller subnets/44
/33 (2)/34 (4)/35 (8)/36 (16)/40 (256)/44 (4,096)/48 (65,536)

2a67:dd::/32 makes 4,096 subnets of /44; the first 256 are listed.

Subnets
#SubnetLast address
12a67:dd::/442a67:dd:f:ffff:ffff:ffff:ffff:ffff
22a67:dd:10::/442a67:dd:1f:ffff:ffff:ffff:ffff:ffff
32a67:dd:20::/442a67:dd:2f:ffff:ffff:ffff:ffff:ffff
42a67:dd:30::/442a67:dd:3f:ffff:ffff:ffff:ffff:ffff
52a67:dd:40::/442a67:dd:4f:ffff:ffff:ffff:ffff:ffff
62a67:dd:50::/442a67:dd:5f:ffff:ffff:ffff:ffff:ffff
72a67:dd:60::/442a67:dd:6f:ffff:ffff:ffff:ffff:ffff
82a67:dd:70::/442a67:dd:7f:ffff:ffff:ffff:ffff:ffff
92a67:dd:80::/442a67:dd:8f:ffff:ffff:ffff:ffff:ffff
102a67:dd:90::/442a67:dd:9f:ffff:ffff:ffff:ffff:ffff
112a67:dd:a0::/442a67:dd:af:ffff:ffff:ffff:ffff:ffff
122a67:dd:b0::/442a67:dd:bf:ffff:ffff:ffff:ffff:ffff
132a67:dd:c0::/442a67:dd:cf:ffff:ffff:ffff:ffff:ffff
142a67:dd:d0::/442a67:dd:df:ffff:ffff:ffff:ffff:ffff
152a67:dd:e0::/442a67:dd:ef:ffff:ffff:ffff:ffff:ffff
162a67:dd:f0::/442a67:dd:ff:ffff:ffff:ffff:ffff:ffff
172a67:dd:100::/442a67:dd:10f:ffff:ffff:ffff:ffff:ffff
182a67:dd:110::/442a67:dd:11f:ffff:ffff:ffff:ffff:ffff
192a67:dd:120::/442a67:dd:12f:ffff:ffff:ffff:ffff:ffff
202a67:dd:130::/442a67:dd:13f:ffff:ffff:ffff:ffff:ffff
212a67:dd:140::/442a67:dd:14f:ffff:ffff:ffff:ffff:ffff
222a67:dd:150::/442a67:dd:15f:ffff:ffff:ffff:ffff:ffff
232a67:dd:160::/442a67:dd:16f:ffff:ffff:ffff:ffff:ffff
242a67:dd:170::/442a67:dd:17f:ffff:ffff:ffff:ffff:ffff
252a67:dd:180::/442a67:dd:18f:ffff:ffff:ffff:ffff:ffff
262a67:dd:190::/442a67:dd:19f:ffff:ffff:ffff:ffff:ffff
272a67:dd:1a0::/442a67:dd:1af:ffff:ffff:ffff:ffff:ffff
282a67:dd:1b0::/442a67:dd:1bf:ffff:ffff:ffff:ffff:ffff
292a67:dd:1c0::/442a67:dd:1cf:ffff:ffff:ffff:ffff:ffff
302a67:dd:1d0::/442a67:dd:1df:ffff:ffff:ffff:ffff:ffff
312a67:dd:1e0::/442a67:dd:1ef:ffff:ffff:ffff:ffff:ffff
322a67:dd:1f0::/442a67:dd:1ff:ffff:ffff:ffff:ffff:ffff
332a67:dd:200::/442a67:dd:20f:ffff:ffff:ffff:ffff:ffff
342a67:dd:210::/442a67:dd:21f:ffff:ffff:ffff:ffff:ffff
352a67:dd:220::/442a67:dd:22f:ffff:ffff:ffff:ffff:ffff
362a67:dd:230::/442a67:dd:23f:ffff:ffff:ffff:ffff:ffff
372a67:dd:240::/442a67:dd:24f:ffff:ffff:ffff:ffff:ffff
382a67:dd:250::/442a67:dd:25f:ffff:ffff:ffff:ffff:ffff
392a67:dd:260::/442a67:dd:26f:ffff:ffff:ffff:ffff:ffff
402a67:dd:270::/442a67:dd:27f:ffff:ffff:ffff:ffff:ffff
412a67:dd:280::/442a67:dd:28f:ffff:ffff:ffff:ffff:ffff
422a67:dd:290::/442a67:dd:29f:ffff:ffff:ffff:ffff:ffff
432a67:dd:2a0::/442a67:dd:2af:ffff:ffff:ffff:ffff:ffff
442a67:dd:2b0::/442a67:dd:2bf:ffff:ffff:ffff:ffff:ffff
452a67:dd:2c0::/442a67:dd:2cf:ffff:ffff:ffff:ffff:ffff
462a67:dd:2d0::/442a67:dd:2df:ffff:ffff:ffff:ffff:ffff
472a67:dd:2e0::/442a67:dd:2ef:ffff:ffff:ffff:ffff:ffff
482a67:dd:2f0::/442a67:dd:2ff:ffff:ffff:ffff:ffff:ffff
492a67:dd:300::/442a67:dd:30f:ffff:ffff:ffff:ffff:ffff
502a67:dd:310::/442a67:dd:31f:ffff:ffff:ffff:ffff:ffff
512a67:dd:320::/442a67:dd:32f:ffff:ffff:ffff:ffff:ffff
522a67:dd:330::/442a67:dd:33f:ffff:ffff:ffff:ffff:ffff
532a67:dd:340::/442a67:dd:34f:ffff:ffff:ffff:ffff:ffff
542a67:dd:350::/442a67:dd:35f:ffff:ffff:ffff:ffff:ffff
552a67:dd:360::/442a67:dd:36f:ffff:ffff:ffff:ffff:ffff
562a67:dd:370::/442a67:dd:37f:ffff:ffff:ffff:ffff:ffff
572a67:dd:380::/442a67:dd:38f:ffff:ffff:ffff:ffff:ffff
582a67:dd:390::/442a67:dd:39f:ffff:ffff:ffff:ffff:ffff
592a67:dd:3a0::/442a67:dd:3af:ffff:ffff:ffff:ffff:ffff
602a67:dd:3b0::/442a67:dd:3bf:ffff:ffff:ffff:ffff:ffff
612a67:dd:3c0::/442a67:dd:3cf:ffff:ffff:ffff:ffff:ffff
622a67:dd:3d0::/442a67:dd:3df:ffff:ffff:ffff:ffff:ffff
632a67:dd:3e0::/442a67:dd:3ef:ffff:ffff:ffff:ffff:ffff
642a67:dd:3f0::/442a67:dd:3ff:ffff:ffff:ffff:ffff:ffff
652a67:dd:400::/442a67:dd:40f:ffff:ffff:ffff:ffff:ffff
662a67:dd:410::/442a67:dd:41f:ffff:ffff:ffff:ffff:ffff
672a67:dd:420::/442a67:dd:42f:ffff:ffff:ffff:ffff:ffff
682a67:dd:430::/442a67:dd:43f:ffff:ffff:ffff:ffff:ffff
692a67:dd:440::/442a67:dd:44f:ffff:ffff:ffff:ffff:ffff
702a67:dd:450::/442a67:dd:45f:ffff:ffff:ffff:ffff:ffff
712a67:dd:460::/442a67:dd:46f:ffff:ffff:ffff:ffff:ffff
722a67:dd:470::/442a67:dd:47f:ffff:ffff:ffff:ffff:ffff
732a67:dd:480::/442a67:dd:48f:ffff:ffff:ffff:ffff:ffff
742a67:dd:490::/442a67:dd:49f:ffff:ffff:ffff:ffff:ffff
752a67:dd:4a0::/442a67:dd:4af:ffff:ffff:ffff:ffff:ffff
762a67:dd:4b0::/442a67:dd:4bf:ffff:ffff:ffff:ffff:ffff
772a67:dd:4c0::/442a67:dd:4cf:ffff:ffff:ffff:ffff:ffff
782a67:dd:4d0::/442a67:dd:4df:ffff:ffff:ffff:ffff:ffff
792a67:dd:4e0::/442a67:dd:4ef:ffff:ffff:ffff:ffff:ffff
802a67:dd:4f0::/442a67:dd:4ff:ffff:ffff:ffff:ffff:ffff
812a67:dd:500::/442a67:dd:50f:ffff:ffff:ffff:ffff:ffff
822a67:dd:510::/442a67:dd:51f:ffff:ffff:ffff:ffff:ffff
832a67:dd:520::/442a67:dd:52f:ffff:ffff:ffff:ffff:ffff
842a67:dd:530::/442a67:dd:53f:ffff:ffff:ffff:ffff:ffff
852a67:dd:540::/442a67:dd:54f:ffff:ffff:ffff:ffff:ffff
862a67:dd:550::/442a67:dd:55f:ffff:ffff:ffff:ffff:ffff
872a67:dd:560::/442a67:dd:56f:ffff:ffff:ffff:ffff:ffff
882a67:dd:570::/442a67:dd:57f:ffff:ffff:ffff:ffff:ffff
892a67:dd:580::/442a67:dd:58f:ffff:ffff:ffff:ffff:ffff
902a67:dd:590::/442a67:dd:59f:ffff:ffff:ffff:ffff:ffff
912a67:dd:5a0::/442a67:dd:5af:ffff:ffff:ffff:ffff:ffff
922a67:dd:5b0::/442a67:dd:5bf:ffff:ffff:ffff:ffff:ffff
932a67:dd:5c0::/442a67:dd:5cf:ffff:ffff:ffff:ffff:ffff
942a67:dd:5d0::/442a67:dd:5df:ffff:ffff:ffff:ffff:ffff
952a67:dd:5e0::/442a67:dd:5ef:ffff:ffff:ffff:ffff:ffff
962a67:dd:5f0::/442a67:dd:5ff:ffff:ffff:ffff:ffff:ffff
972a67:dd:600::/442a67:dd:60f:ffff:ffff:ffff:ffff:ffff
982a67:dd:610::/442a67:dd:61f:ffff:ffff:ffff:ffff:ffff
992a67:dd:620::/442a67:dd:62f:ffff:ffff:ffff:ffff:ffff
1002a67:dd:630::/442a67:dd:63f:ffff:ffff:ffff:ffff:ffff
1012a67:dd:640::/442a67:dd:64f:ffff:ffff:ffff:ffff:ffff
1022a67:dd:650::/442a67:dd:65f:ffff:ffff:ffff:ffff:ffff
1032a67:dd:660::/442a67:dd:66f:ffff:ffff:ffff:ffff:ffff
1042a67:dd:670::/442a67:dd:67f:ffff:ffff:ffff:ffff:ffff
1052a67:dd:680::/442a67:dd:68f:ffff:ffff:ffff:ffff:ffff
1062a67:dd:690::/442a67:dd:69f:ffff:ffff:ffff:ffff:ffff
1072a67:dd:6a0::/442a67:dd:6af:ffff:ffff:ffff:ffff:ffff
1082a67:dd:6b0::/442a67:dd:6bf:ffff:ffff:ffff:ffff:ffff
1092a67:dd:6c0::/442a67:dd:6cf:ffff:ffff:ffff:ffff:ffff
1102a67:dd:6d0::/442a67:dd:6df:ffff:ffff:ffff:ffff:ffff
1112a67:dd:6e0::/442a67:dd:6ef:ffff:ffff:ffff:ffff:ffff
1122a67:dd:6f0::/442a67:dd:6ff:ffff:ffff:ffff:ffff:ffff
1132a67:dd:700::/442a67:dd:70f:ffff:ffff:ffff:ffff:ffff
1142a67:dd:710::/442a67:dd:71f:ffff:ffff:ffff:ffff:ffff
1152a67:dd:720::/442a67:dd:72f:ffff:ffff:ffff:ffff:ffff
1162a67:dd:730::/442a67:dd:73f:ffff:ffff:ffff:ffff:ffff
1172a67:dd:740::/442a67:dd:74f:ffff:ffff:ffff:ffff:ffff
1182a67:dd:750::/442a67:dd:75f:ffff:ffff:ffff:ffff:ffff
1192a67:dd:760::/442a67:dd:76f:ffff:ffff:ffff:ffff:ffff
1202a67:dd:770::/442a67:dd:77f:ffff:ffff:ffff:ffff:ffff
1212a67:dd:780::/442a67:dd:78f:ffff:ffff:ffff:ffff:ffff
1222a67:dd:790::/442a67:dd:79f:ffff:ffff:ffff:ffff:ffff
1232a67:dd:7a0::/442a67:dd:7af:ffff:ffff:ffff:ffff:ffff
1242a67:dd:7b0::/442a67:dd:7bf:ffff:ffff:ffff:ffff:ffff
1252a67:dd:7c0::/442a67:dd:7cf:ffff:ffff:ffff:ffff:ffff
1262a67:dd:7d0::/442a67:dd:7df:ffff:ffff:ffff:ffff:ffff
1272a67:dd:7e0::/442a67:dd:7ef:ffff:ffff:ffff:ffff:ffff
1282a67:dd:7f0::/442a67:dd:7ff:ffff:ffff:ffff:ffff:ffff
1292a67:dd:800::/442a67:dd:80f:ffff:ffff:ffff:ffff:ffff
1302a67:dd:810::/442a67:dd:81f:ffff:ffff:ffff:ffff:ffff
1312a67:dd:820::/442a67:dd:82f:ffff:ffff:ffff:ffff:ffff
1322a67:dd:830::/442a67:dd:83f:ffff:ffff:ffff:ffff:ffff
1332a67:dd:840::/442a67:dd:84f:ffff:ffff:ffff:ffff:ffff
1342a67:dd:850::/442a67:dd:85f:ffff:ffff:ffff:ffff:ffff
1352a67:dd:860::/442a67:dd:86f:ffff:ffff:ffff:ffff:ffff
1362a67:dd:870::/442a67:dd:87f:ffff:ffff:ffff:ffff:ffff
1372a67:dd:880::/442a67:dd:88f:ffff:ffff:ffff:ffff:ffff
1382a67:dd:890::/442a67:dd:89f:ffff:ffff:ffff:ffff:ffff
1392a67:dd:8a0::/442a67:dd:8af:ffff:ffff:ffff:ffff:ffff
1402a67:dd:8b0::/442a67:dd:8bf:ffff:ffff:ffff:ffff:ffff
1412a67:dd:8c0::/442a67:dd:8cf:ffff:ffff:ffff:ffff:ffff
1422a67:dd:8d0::/442a67:dd:8df:ffff:ffff:ffff:ffff:ffff
1432a67:dd:8e0::/442a67:dd:8ef:ffff:ffff:ffff:ffff:ffff
1442a67:dd:8f0::/442a67:dd:8ff:ffff:ffff:ffff:ffff:ffff
1452a67:dd:900::/442a67:dd:90f:ffff:ffff:ffff:ffff:ffff
1462a67:dd:910::/442a67:dd:91f:ffff:ffff:ffff:ffff:ffff
1472a67:dd:920::/442a67:dd:92f:ffff:ffff:ffff:ffff:ffff
1482a67:dd:930::/442a67:dd:93f:ffff:ffff:ffff:ffff:ffff
1492a67:dd:940::/442a67:dd:94f:ffff:ffff:ffff:ffff:ffff
1502a67:dd:950::/442a67:dd:95f:ffff:ffff:ffff:ffff:ffff
1512a67:dd:960::/442a67:dd:96f:ffff:ffff:ffff:ffff:ffff
1522a67:dd:970::/442a67:dd:97f:ffff:ffff:ffff:ffff:ffff
1532a67:dd:980::/442a67:dd:98f:ffff:ffff:ffff:ffff:ffff
1542a67:dd:990::/442a67:dd:99f:ffff:ffff:ffff:ffff:ffff
1552a67:dd:9a0::/442a67:dd:9af:ffff:ffff:ffff:ffff:ffff
1562a67:dd:9b0::/442a67:dd:9bf:ffff:ffff:ffff:ffff:ffff
1572a67:dd:9c0::/442a67:dd:9cf:ffff:ffff:ffff:ffff:ffff
1582a67:dd:9d0::/442a67:dd:9df:ffff:ffff:ffff:ffff:ffff
1592a67:dd:9e0::/442a67:dd:9ef:ffff:ffff:ffff:ffff:ffff
1602a67:dd:9f0::/442a67:dd:9ff:ffff:ffff:ffff:ffff:ffff
1612a67:dd:a00::/442a67:dd:a0f:ffff:ffff:ffff:ffff:ffff
1622a67:dd:a10::/442a67:dd:a1f:ffff:ffff:ffff:ffff:ffff
1632a67:dd:a20::/442a67:dd:a2f:ffff:ffff:ffff:ffff:ffff
1642a67:dd:a30::/442a67:dd:a3f:ffff:ffff:ffff:ffff:ffff
1652a67:dd:a40::/442a67:dd:a4f:ffff:ffff:ffff:ffff:ffff
1662a67:dd:a50::/442a67:dd:a5f:ffff:ffff:ffff:ffff:ffff
1672a67:dd:a60::/442a67:dd:a6f:ffff:ffff:ffff:ffff:ffff
1682a67:dd:a70::/442a67:dd:a7f:ffff:ffff:ffff:ffff:ffff
1692a67:dd:a80::/442a67:dd:a8f:ffff:ffff:ffff:ffff:ffff
1702a67:dd:a90::/442a67:dd:a9f:ffff:ffff:ffff:ffff:ffff
1712a67:dd:aa0::/442a67:dd:aaf:ffff:ffff:ffff:ffff:ffff
1722a67:dd:ab0::/442a67:dd:abf:ffff:ffff:ffff:ffff:ffff
1732a67:dd:ac0::/442a67:dd:acf:ffff:ffff:ffff:ffff:ffff
1742a67:dd:ad0::/442a67:dd:adf:ffff:ffff:ffff:ffff:ffff
1752a67:dd:ae0::/442a67:dd:aef:ffff:ffff:ffff:ffff:ffff
1762a67:dd:af0::/442a67:dd:aff:ffff:ffff:ffff:ffff:ffff
1772a67:dd:b00::/442a67:dd:b0f:ffff:ffff:ffff:ffff:ffff
1782a67:dd:b10::/442a67:dd:b1f:ffff:ffff:ffff:ffff:ffff
1792a67:dd:b20::/442a67:dd:b2f:ffff:ffff:ffff:ffff:ffff
1802a67:dd:b30::/442a67:dd:b3f:ffff:ffff:ffff:ffff:ffff
1812a67:dd:b40::/442a67:dd:b4f:ffff:ffff:ffff:ffff:ffff
1822a67:dd:b50::/442a67:dd:b5f:ffff:ffff:ffff:ffff:ffff
1832a67:dd:b60::/442a67:dd:b6f:ffff:ffff:ffff:ffff:ffff
1842a67:dd:b70::/442a67:dd:b7f:ffff:ffff:ffff:ffff:ffff
1852a67:dd:b80::/442a67:dd:b8f:ffff:ffff:ffff:ffff:ffff
1862a67:dd:b90::/442a67:dd:b9f:ffff:ffff:ffff:ffff:ffff
1872a67:dd:ba0::/442a67:dd:baf:ffff:ffff:ffff:ffff:ffff
1882a67:dd:bb0::/442a67:dd:bbf:ffff:ffff:ffff:ffff:ffff
1892a67:dd:bc0::/442a67:dd:bcf:ffff:ffff:ffff:ffff:ffff
1902a67:dd:bd0::/442a67:dd:bdf:ffff:ffff:ffff:ffff:ffff
1912a67:dd:be0::/442a67:dd:bef:ffff:ffff:ffff:ffff:ffff
1922a67:dd:bf0::/442a67:dd:bff:ffff:ffff:ffff:ffff:ffff
1932a67:dd:c00::/442a67:dd:c0f:ffff:ffff:ffff:ffff:ffff
1942a67:dd:c10::/442a67:dd:c1f:ffff:ffff:ffff:ffff:ffff
1952a67:dd:c20::/442a67:dd:c2f:ffff:ffff:ffff:ffff:ffff
1962a67:dd:c30::/442a67:dd:c3f:ffff:ffff:ffff:ffff:ffff
1972a67:dd:c40::/442a67:dd:c4f:ffff:ffff:ffff:ffff:ffff
1982a67:dd:c50::/442a67:dd:c5f:ffff:ffff:ffff:ffff:ffff
1992a67:dd:c60::/442a67:dd:c6f:ffff:ffff:ffff:ffff:ffff
2002a67:dd:c70::/442a67:dd:c7f:ffff:ffff:ffff:ffff:ffff
2012a67:dd:c80::/442a67:dd:c8f:ffff:ffff:ffff:ffff:ffff
2022a67:dd:c90::/442a67:dd:c9f:ffff:ffff:ffff:ffff:ffff
2032a67:dd:ca0::/442a67:dd:caf:ffff:ffff:ffff:ffff:ffff
2042a67:dd:cb0::/442a67:dd:cbf:ffff:ffff:ffff:ffff:ffff
2052a67:dd:cc0::/442a67:dd:ccf:ffff:ffff:ffff:ffff:ffff
2062a67:dd:cd0::/442a67:dd:cdf:ffff:ffff:ffff:ffff:ffff
2072a67:dd:ce0::/442a67:dd:cef:ffff:ffff:ffff:ffff:ffff
2082a67:dd:cf0::/442a67:dd:cff:ffff:ffff:ffff:ffff:ffff
2092a67:dd:d00::/442a67:dd:d0f:ffff:ffff:ffff:ffff:ffff
2102a67:dd:d10::/442a67:dd:d1f:ffff:ffff:ffff:ffff:ffff
2112a67:dd:d20::/442a67:dd:d2f:ffff:ffff:ffff:ffff:ffff
2122a67:dd:d30::/442a67:dd:d3f:ffff:ffff:ffff:ffff:ffff
2132a67:dd:d40::/442a67:dd:d4f:ffff:ffff:ffff:ffff:ffff
2142a67:dd:d50::/442a67:dd:d5f:ffff:ffff:ffff:ffff:ffff
2152a67:dd:d60::/442a67:dd:d6f:ffff:ffff:ffff:ffff:ffff
2162a67:dd:d70::/442a67:dd:d7f:ffff:ffff:ffff:ffff:ffff
2172a67:dd:d80::/442a67:dd:d8f:ffff:ffff:ffff:ffff:ffff
2182a67:dd:d90::/442a67:dd:d9f:ffff:ffff:ffff:ffff:ffff
2192a67:dd:da0::/442a67:dd:daf:ffff:ffff:ffff:ffff:ffff
2202a67:dd:db0::/442a67:dd:dbf:ffff:ffff:ffff:ffff:ffff
2212a67:dd:dc0::/442a67:dd:dcf:ffff:ffff:ffff:ffff:ffff
2222a67:dd:dd0::/442a67:dd:ddf:ffff:ffff:ffff:ffff:ffff
2232a67:dd:de0::/442a67:dd:def:ffff:ffff:ffff:ffff:ffff
2242a67:dd:df0::/442a67:dd:dff:ffff:ffff:ffff:ffff:ffff
2252a67:dd:e00::/442a67:dd:e0f:ffff:ffff:ffff:ffff:ffff
2262a67:dd:e10::/442a67:dd:e1f:ffff:ffff:ffff:ffff:ffff
2272a67:dd:e20::/442a67:dd:e2f:ffff:ffff:ffff:ffff:ffff
2282a67:dd:e30::/442a67:dd:e3f:ffff:ffff:ffff:ffff:ffff
2292a67:dd:e40::/442a67:dd:e4f:ffff:ffff:ffff:ffff:ffff
2302a67:dd:e50::/442a67:dd:e5f:ffff:ffff:ffff:ffff:ffff
2312a67:dd:e60::/442a67:dd:e6f:ffff:ffff:ffff:ffff:ffff
2322a67:dd:e70::/442a67:dd:e7f:ffff:ffff:ffff:ffff:ffff
2332a67:dd:e80::/442a67:dd:e8f:ffff:ffff:ffff:ffff:ffff
2342a67:dd:e90::/442a67:dd:e9f:ffff:ffff:ffff:ffff:ffff
2352a67:dd:ea0::/442a67:dd:eaf:ffff:ffff:ffff:ffff:ffff
2362a67:dd:eb0::/442a67:dd:ebf:ffff:ffff:ffff:ffff:ffff
2372a67:dd:ec0::/442a67:dd:ecf:ffff:ffff:ffff:ffff:ffff
2382a67:dd:ed0::/442a67:dd:edf:ffff:ffff:ffff:ffff:ffff
2392a67:dd:ee0::/442a67:dd:eef:ffff:ffff:ffff:ffff:ffff
2402a67:dd:ef0::/442a67:dd:eff:ffff:ffff:ffff:ffff:ffff
2412a67:dd:f00::/442a67:dd:f0f:ffff:ffff:ffff:ffff:ffff
2422a67:dd:f10::/442a67:dd:f1f:ffff:ffff:ffff:ffff:ffff
2432a67:dd:f20::/442a67:dd:f2f:ffff:ffff:ffff:ffff:ffff
2442a67:dd:f30::/442a67:dd:f3f:ffff:ffff:ffff:ffff:ffff
2452a67:dd:f40::/442a67:dd:f4f:ffff:ffff:ffff:ffff:ffff
2462a67:dd:f50::/442a67:dd:f5f:ffff:ffff:ffff:ffff:ffff
2472a67:dd:f60::/442a67:dd:f6f:ffff:ffff:ffff:ffff:ffff
2482a67:dd:f70::/442a67:dd:f7f:ffff:ffff:ffff:ffff:ffff
2492a67:dd:f80::/442a67:dd:f8f:ffff:ffff:ffff:ffff:ffff
2502a67:dd:f90::/442a67:dd:f9f:ffff:ffff:ffff:ffff:ffff
2512a67:dd:fa0::/442a67:dd:faf:ffff:ffff:ffff:ffff:ffff
2522a67:dd:fb0::/442a67:dd:fbf:ffff:ffff:ffff:ffff:ffff
2532a67:dd:fc0::/442a67:dd:fcf:ffff:ffff:ffff:ffff:ffff
2542a67:dd:fd0::/442a67:dd:fdf:ffff:ffff:ffff:ffff:ffff
2552a67:dd:fe0::/442a67:dd:fef:ffff:ffff:ffff:ffff:ffff
2562a67:dd:ff0::/442a67:dd:fff:ffff:ffff:ffff:ffff: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.