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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/16
Addresses2^112
/64 networks2^48
Network
2ea9::/16
First address
2ea9::
Last address
2ea9:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
5,192,296,858,534,827,628,530,496,329,220,096 (2^112)
/64 networks (LANs)
281,474,976,710,656 (2^48)
Full form
2ea9:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.a.e.2.ip6.arpa
Split into smaller subnets/28
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

2ea9::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
12ea9::/282ea9:f:ffff:ffff:ffff:ffff:ffff:ffff
22ea9:10::/282ea9:1f:ffff:ffff:ffff:ffff:ffff:ffff
32ea9:20::/282ea9:2f:ffff:ffff:ffff:ffff:ffff:ffff
42ea9:30::/282ea9:3f:ffff:ffff:ffff:ffff:ffff:ffff
52ea9:40::/282ea9:4f:ffff:ffff:ffff:ffff:ffff:ffff
62ea9:50::/282ea9:5f:ffff:ffff:ffff:ffff:ffff:ffff
72ea9:60::/282ea9:6f:ffff:ffff:ffff:ffff:ffff:ffff
82ea9:70::/282ea9:7f:ffff:ffff:ffff:ffff:ffff:ffff
92ea9:80::/282ea9:8f:ffff:ffff:ffff:ffff:ffff:ffff
102ea9:90::/282ea9:9f:ffff:ffff:ffff:ffff:ffff:ffff
112ea9:a0::/282ea9:af:ffff:ffff:ffff:ffff:ffff:ffff
122ea9:b0::/282ea9:bf:ffff:ffff:ffff:ffff:ffff:ffff
132ea9:c0::/282ea9:cf:ffff:ffff:ffff:ffff:ffff:ffff
142ea9:d0::/282ea9:df:ffff:ffff:ffff:ffff:ffff:ffff
152ea9:e0::/282ea9:ef:ffff:ffff:ffff:ffff:ffff:ffff
162ea9:f0::/282ea9:ff:ffff:ffff:ffff:ffff:ffff:ffff
172ea9:100::/282ea9:10f:ffff:ffff:ffff:ffff:ffff:ffff
182ea9:110::/282ea9:11f:ffff:ffff:ffff:ffff:ffff:ffff
192ea9:120::/282ea9:12f:ffff:ffff:ffff:ffff:ffff:ffff
202ea9:130::/282ea9:13f:ffff:ffff:ffff:ffff:ffff:ffff
212ea9:140::/282ea9:14f:ffff:ffff:ffff:ffff:ffff:ffff
222ea9:150::/282ea9:15f:ffff:ffff:ffff:ffff:ffff:ffff
232ea9:160::/282ea9:16f:ffff:ffff:ffff:ffff:ffff:ffff
242ea9:170::/282ea9:17f:ffff:ffff:ffff:ffff:ffff:ffff
252ea9:180::/282ea9:18f:ffff:ffff:ffff:ffff:ffff:ffff
262ea9:190::/282ea9:19f:ffff:ffff:ffff:ffff:ffff:ffff
272ea9:1a0::/282ea9:1af:ffff:ffff:ffff:ffff:ffff:ffff
282ea9:1b0::/282ea9:1bf:ffff:ffff:ffff:ffff:ffff:ffff
292ea9:1c0::/282ea9:1cf:ffff:ffff:ffff:ffff:ffff:ffff
302ea9:1d0::/282ea9:1df:ffff:ffff:ffff:ffff:ffff:ffff
312ea9:1e0::/282ea9:1ef:ffff:ffff:ffff:ffff:ffff:ffff
322ea9:1f0::/282ea9:1ff:ffff:ffff:ffff:ffff:ffff:ffff
332ea9:200::/282ea9:20f:ffff:ffff:ffff:ffff:ffff:ffff
342ea9:210::/282ea9:21f:ffff:ffff:ffff:ffff:ffff:ffff
352ea9:220::/282ea9:22f:ffff:ffff:ffff:ffff:ffff:ffff
362ea9:230::/282ea9:23f:ffff:ffff:ffff:ffff:ffff:ffff
372ea9:240::/282ea9:24f:ffff:ffff:ffff:ffff:ffff:ffff
382ea9:250::/282ea9:25f:ffff:ffff:ffff:ffff:ffff:ffff
392ea9:260::/282ea9:26f:ffff:ffff:ffff:ffff:ffff:ffff
402ea9:270::/282ea9:27f:ffff:ffff:ffff:ffff:ffff:ffff
412ea9:280::/282ea9:28f:ffff:ffff:ffff:ffff:ffff:ffff
422ea9:290::/282ea9:29f:ffff:ffff:ffff:ffff:ffff:ffff
432ea9:2a0::/282ea9:2af:ffff:ffff:ffff:ffff:ffff:ffff
442ea9:2b0::/282ea9:2bf:ffff:ffff:ffff:ffff:ffff:ffff
452ea9:2c0::/282ea9:2cf:ffff:ffff:ffff:ffff:ffff:ffff
462ea9:2d0::/282ea9:2df:ffff:ffff:ffff:ffff:ffff:ffff
472ea9:2e0::/282ea9:2ef:ffff:ffff:ffff:ffff:ffff:ffff
482ea9:2f0::/282ea9:2ff:ffff:ffff:ffff:ffff:ffff:ffff
492ea9:300::/282ea9:30f:ffff:ffff:ffff:ffff:ffff:ffff
502ea9:310::/282ea9:31f:ffff:ffff:ffff:ffff:ffff:ffff
512ea9:320::/282ea9:32f:ffff:ffff:ffff:ffff:ffff:ffff
522ea9:330::/282ea9:33f:ffff:ffff:ffff:ffff:ffff:ffff
532ea9:340::/282ea9:34f:ffff:ffff:ffff:ffff:ffff:ffff
542ea9:350::/282ea9:35f:ffff:ffff:ffff:ffff:ffff:ffff
552ea9:360::/282ea9:36f:ffff:ffff:ffff:ffff:ffff:ffff
562ea9:370::/282ea9:37f:ffff:ffff:ffff:ffff:ffff:ffff
572ea9:380::/282ea9:38f:ffff:ffff:ffff:ffff:ffff:ffff
582ea9:390::/282ea9:39f:ffff:ffff:ffff:ffff:ffff:ffff
592ea9:3a0::/282ea9:3af:ffff:ffff:ffff:ffff:ffff:ffff
602ea9:3b0::/282ea9:3bf:ffff:ffff:ffff:ffff:ffff:ffff
612ea9:3c0::/282ea9:3cf:ffff:ffff:ffff:ffff:ffff:ffff
622ea9:3d0::/282ea9:3df:ffff:ffff:ffff:ffff:ffff:ffff
632ea9:3e0::/282ea9:3ef:ffff:ffff:ffff:ffff:ffff:ffff
642ea9:3f0::/282ea9:3ff:ffff:ffff:ffff:ffff:ffff:ffff
652ea9:400::/282ea9:40f:ffff:ffff:ffff:ffff:ffff:ffff
662ea9:410::/282ea9:41f:ffff:ffff:ffff:ffff:ffff:ffff
672ea9:420::/282ea9:42f:ffff:ffff:ffff:ffff:ffff:ffff
682ea9:430::/282ea9:43f:ffff:ffff:ffff:ffff:ffff:ffff
692ea9:440::/282ea9:44f:ffff:ffff:ffff:ffff:ffff:ffff
702ea9:450::/282ea9:45f:ffff:ffff:ffff:ffff:ffff:ffff
712ea9:460::/282ea9:46f:ffff:ffff:ffff:ffff:ffff:ffff
722ea9:470::/282ea9:47f:ffff:ffff:ffff:ffff:ffff:ffff
732ea9:480::/282ea9:48f:ffff:ffff:ffff:ffff:ffff:ffff
742ea9:490::/282ea9:49f:ffff:ffff:ffff:ffff:ffff:ffff
752ea9:4a0::/282ea9:4af:ffff:ffff:ffff:ffff:ffff:ffff
762ea9:4b0::/282ea9:4bf:ffff:ffff:ffff:ffff:ffff:ffff
772ea9:4c0::/282ea9:4cf:ffff:ffff:ffff:ffff:ffff:ffff
782ea9:4d0::/282ea9:4df:ffff:ffff:ffff:ffff:ffff:ffff
792ea9:4e0::/282ea9:4ef:ffff:ffff:ffff:ffff:ffff:ffff
802ea9:4f0::/282ea9:4ff:ffff:ffff:ffff:ffff:ffff:ffff
812ea9:500::/282ea9:50f:ffff:ffff:ffff:ffff:ffff:ffff
822ea9:510::/282ea9:51f:ffff:ffff:ffff:ffff:ffff:ffff
832ea9:520::/282ea9:52f:ffff:ffff:ffff:ffff:ffff:ffff
842ea9:530::/282ea9:53f:ffff:ffff:ffff:ffff:ffff:ffff
852ea9:540::/282ea9:54f:ffff:ffff:ffff:ffff:ffff:ffff
862ea9:550::/282ea9:55f:ffff:ffff:ffff:ffff:ffff:ffff
872ea9:560::/282ea9:56f:ffff:ffff:ffff:ffff:ffff:ffff
882ea9:570::/282ea9:57f:ffff:ffff:ffff:ffff:ffff:ffff
892ea9:580::/282ea9:58f:ffff:ffff:ffff:ffff:ffff:ffff
902ea9:590::/282ea9:59f:ffff:ffff:ffff:ffff:ffff:ffff
912ea9:5a0::/282ea9:5af:ffff:ffff:ffff:ffff:ffff:ffff
922ea9:5b0::/282ea9:5bf:ffff:ffff:ffff:ffff:ffff:ffff
932ea9:5c0::/282ea9:5cf:ffff:ffff:ffff:ffff:ffff:ffff
942ea9:5d0::/282ea9:5df:ffff:ffff:ffff:ffff:ffff:ffff
952ea9:5e0::/282ea9:5ef:ffff:ffff:ffff:ffff:ffff:ffff
962ea9:5f0::/282ea9:5ff:ffff:ffff:ffff:ffff:ffff:ffff
972ea9:600::/282ea9:60f:ffff:ffff:ffff:ffff:ffff:ffff
982ea9:610::/282ea9:61f:ffff:ffff:ffff:ffff:ffff:ffff
992ea9:620::/282ea9:62f:ffff:ffff:ffff:ffff:ffff:ffff
1002ea9:630::/282ea9:63f:ffff:ffff:ffff:ffff:ffff:ffff
1012ea9:640::/282ea9:64f:ffff:ffff:ffff:ffff:ffff:ffff
1022ea9:650::/282ea9:65f:ffff:ffff:ffff:ffff:ffff:ffff
1032ea9:660::/282ea9:66f:ffff:ffff:ffff:ffff:ffff:ffff
1042ea9:670::/282ea9:67f:ffff:ffff:ffff:ffff:ffff:ffff
1052ea9:680::/282ea9:68f:ffff:ffff:ffff:ffff:ffff:ffff
1062ea9:690::/282ea9:69f:ffff:ffff:ffff:ffff:ffff:ffff
1072ea9:6a0::/282ea9:6af:ffff:ffff:ffff:ffff:ffff:ffff
1082ea9:6b0::/282ea9:6bf:ffff:ffff:ffff:ffff:ffff:ffff
1092ea9:6c0::/282ea9:6cf:ffff:ffff:ffff:ffff:ffff:ffff
1102ea9:6d0::/282ea9:6df:ffff:ffff:ffff:ffff:ffff:ffff
1112ea9:6e0::/282ea9:6ef:ffff:ffff:ffff:ffff:ffff:ffff
1122ea9:6f0::/282ea9:6ff:ffff:ffff:ffff:ffff:ffff:ffff
1132ea9:700::/282ea9:70f:ffff:ffff:ffff:ffff:ffff:ffff
1142ea9:710::/282ea9:71f:ffff:ffff:ffff:ffff:ffff:ffff
1152ea9:720::/282ea9:72f:ffff:ffff:ffff:ffff:ffff:ffff
1162ea9:730::/282ea9:73f:ffff:ffff:ffff:ffff:ffff:ffff
1172ea9:740::/282ea9:74f:ffff:ffff:ffff:ffff:ffff:ffff
1182ea9:750::/282ea9:75f:ffff:ffff:ffff:ffff:ffff:ffff
1192ea9:760::/282ea9:76f:ffff:ffff:ffff:ffff:ffff:ffff
1202ea9:770::/282ea9:77f:ffff:ffff:ffff:ffff:ffff:ffff
1212ea9:780::/282ea9:78f:ffff:ffff:ffff:ffff:ffff:ffff
1222ea9:790::/282ea9:79f:ffff:ffff:ffff:ffff:ffff:ffff
1232ea9:7a0::/282ea9:7af:ffff:ffff:ffff:ffff:ffff:ffff
1242ea9:7b0::/282ea9:7bf:ffff:ffff:ffff:ffff:ffff:ffff
1252ea9:7c0::/282ea9:7cf:ffff:ffff:ffff:ffff:ffff:ffff
1262ea9:7d0::/282ea9:7df:ffff:ffff:ffff:ffff:ffff:ffff
1272ea9:7e0::/282ea9:7ef:ffff:ffff:ffff:ffff:ffff:ffff
1282ea9:7f0::/282ea9:7ff:ffff:ffff:ffff:ffff:ffff:ffff
1292ea9:800::/282ea9:80f:ffff:ffff:ffff:ffff:ffff:ffff
1302ea9:810::/282ea9:81f:ffff:ffff:ffff:ffff:ffff:ffff
1312ea9:820::/282ea9:82f:ffff:ffff:ffff:ffff:ffff:ffff
1322ea9:830::/282ea9:83f:ffff:ffff:ffff:ffff:ffff:ffff
1332ea9:840::/282ea9:84f:ffff:ffff:ffff:ffff:ffff:ffff
1342ea9:850::/282ea9:85f:ffff:ffff:ffff:ffff:ffff:ffff
1352ea9:860::/282ea9:86f:ffff:ffff:ffff:ffff:ffff:ffff
1362ea9:870::/282ea9:87f:ffff:ffff:ffff:ffff:ffff:ffff
1372ea9:880::/282ea9:88f:ffff:ffff:ffff:ffff:ffff:ffff
1382ea9:890::/282ea9:89f:ffff:ffff:ffff:ffff:ffff:ffff
1392ea9:8a0::/282ea9:8af:ffff:ffff:ffff:ffff:ffff:ffff
1402ea9:8b0::/282ea9:8bf:ffff:ffff:ffff:ffff:ffff:ffff
1412ea9:8c0::/282ea9:8cf:ffff:ffff:ffff:ffff:ffff:ffff
1422ea9:8d0::/282ea9:8df:ffff:ffff:ffff:ffff:ffff:ffff
1432ea9:8e0::/282ea9:8ef:ffff:ffff:ffff:ffff:ffff:ffff
1442ea9:8f0::/282ea9:8ff:ffff:ffff:ffff:ffff:ffff:ffff
1452ea9:900::/282ea9:90f:ffff:ffff:ffff:ffff:ffff:ffff
1462ea9:910::/282ea9:91f:ffff:ffff:ffff:ffff:ffff:ffff
1472ea9:920::/282ea9:92f:ffff:ffff:ffff:ffff:ffff:ffff
1482ea9:930::/282ea9:93f:ffff:ffff:ffff:ffff:ffff:ffff
1492ea9:940::/282ea9:94f:ffff:ffff:ffff:ffff:ffff:ffff
1502ea9:950::/282ea9:95f:ffff:ffff:ffff:ffff:ffff:ffff
1512ea9:960::/282ea9:96f:ffff:ffff:ffff:ffff:ffff:ffff
1522ea9:970::/282ea9:97f:ffff:ffff:ffff:ffff:ffff:ffff
1532ea9:980::/282ea9:98f:ffff:ffff:ffff:ffff:ffff:ffff
1542ea9:990::/282ea9:99f:ffff:ffff:ffff:ffff:ffff:ffff
1552ea9:9a0::/282ea9:9af:ffff:ffff:ffff:ffff:ffff:ffff
1562ea9:9b0::/282ea9:9bf:ffff:ffff:ffff:ffff:ffff:ffff
1572ea9:9c0::/282ea9:9cf:ffff:ffff:ffff:ffff:ffff:ffff
1582ea9:9d0::/282ea9:9df:ffff:ffff:ffff:ffff:ffff:ffff
1592ea9:9e0::/282ea9:9ef:ffff:ffff:ffff:ffff:ffff:ffff
1602ea9:9f0::/282ea9:9ff:ffff:ffff:ffff:ffff:ffff:ffff
1612ea9:a00::/282ea9:a0f:ffff:ffff:ffff:ffff:ffff:ffff
1622ea9:a10::/282ea9:a1f:ffff:ffff:ffff:ffff:ffff:ffff
1632ea9:a20::/282ea9:a2f:ffff:ffff:ffff:ffff:ffff:ffff
1642ea9:a30::/282ea9:a3f:ffff:ffff:ffff:ffff:ffff:ffff
1652ea9:a40::/282ea9:a4f:ffff:ffff:ffff:ffff:ffff:ffff
1662ea9:a50::/282ea9:a5f:ffff:ffff:ffff:ffff:ffff:ffff
1672ea9:a60::/282ea9:a6f:ffff:ffff:ffff:ffff:ffff:ffff
1682ea9:a70::/282ea9:a7f:ffff:ffff:ffff:ffff:ffff:ffff
1692ea9:a80::/282ea9:a8f:ffff:ffff:ffff:ffff:ffff:ffff
1702ea9:a90::/282ea9:a9f:ffff:ffff:ffff:ffff:ffff:ffff
1712ea9:aa0::/282ea9:aaf:ffff:ffff:ffff:ffff:ffff:ffff
1722ea9:ab0::/282ea9:abf:ffff:ffff:ffff:ffff:ffff:ffff
1732ea9:ac0::/282ea9:acf:ffff:ffff:ffff:ffff:ffff:ffff
1742ea9:ad0::/282ea9:adf:ffff:ffff:ffff:ffff:ffff:ffff
1752ea9:ae0::/282ea9:aef:ffff:ffff:ffff:ffff:ffff:ffff
1762ea9:af0::/282ea9:aff:ffff:ffff:ffff:ffff:ffff:ffff
1772ea9:b00::/282ea9:b0f:ffff:ffff:ffff:ffff:ffff:ffff
1782ea9:b10::/282ea9:b1f:ffff:ffff:ffff:ffff:ffff:ffff
1792ea9:b20::/282ea9:b2f:ffff:ffff:ffff:ffff:ffff:ffff
1802ea9:b30::/282ea9:b3f:ffff:ffff:ffff:ffff:ffff:ffff
1812ea9:b40::/282ea9:b4f:ffff:ffff:ffff:ffff:ffff:ffff
1822ea9:b50::/282ea9:b5f:ffff:ffff:ffff:ffff:ffff:ffff
1832ea9:b60::/282ea9:b6f:ffff:ffff:ffff:ffff:ffff:ffff
1842ea9:b70::/282ea9:b7f:ffff:ffff:ffff:ffff:ffff:ffff
1852ea9:b80::/282ea9:b8f:ffff:ffff:ffff:ffff:ffff:ffff
1862ea9:b90::/282ea9:b9f:ffff:ffff:ffff:ffff:ffff:ffff
1872ea9:ba0::/282ea9:baf:ffff:ffff:ffff:ffff:ffff:ffff
1882ea9:bb0::/282ea9:bbf:ffff:ffff:ffff:ffff:ffff:ffff
1892ea9:bc0::/282ea9:bcf:ffff:ffff:ffff:ffff:ffff:ffff
1902ea9:bd0::/282ea9:bdf:ffff:ffff:ffff:ffff:ffff:ffff
1912ea9:be0::/282ea9:bef:ffff:ffff:ffff:ffff:ffff:ffff
1922ea9:bf0::/282ea9:bff:ffff:ffff:ffff:ffff:ffff:ffff
1932ea9:c00::/282ea9:c0f:ffff:ffff:ffff:ffff:ffff:ffff
1942ea9:c10::/282ea9:c1f:ffff:ffff:ffff:ffff:ffff:ffff
1952ea9:c20::/282ea9:c2f:ffff:ffff:ffff:ffff:ffff:ffff
1962ea9:c30::/282ea9:c3f:ffff:ffff:ffff:ffff:ffff:ffff
1972ea9:c40::/282ea9:c4f:ffff:ffff:ffff:ffff:ffff:ffff
1982ea9:c50::/282ea9:c5f:ffff:ffff:ffff:ffff:ffff:ffff
1992ea9:c60::/282ea9:c6f:ffff:ffff:ffff:ffff:ffff:ffff
2002ea9:c70::/282ea9:c7f:ffff:ffff:ffff:ffff:ffff:ffff
2012ea9:c80::/282ea9:c8f:ffff:ffff:ffff:ffff:ffff:ffff
2022ea9:c90::/282ea9:c9f:ffff:ffff:ffff:ffff:ffff:ffff
2032ea9:ca0::/282ea9:caf:ffff:ffff:ffff:ffff:ffff:ffff
2042ea9:cb0::/282ea9:cbf:ffff:ffff:ffff:ffff:ffff:ffff
2052ea9:cc0::/282ea9:ccf:ffff:ffff:ffff:ffff:ffff:ffff
2062ea9:cd0::/282ea9:cdf:ffff:ffff:ffff:ffff:ffff:ffff
2072ea9:ce0::/282ea9:cef:ffff:ffff:ffff:ffff:ffff:ffff
2082ea9:cf0::/282ea9:cff:ffff:ffff:ffff:ffff:ffff:ffff
2092ea9:d00::/282ea9:d0f:ffff:ffff:ffff:ffff:ffff:ffff
2102ea9:d10::/282ea9:d1f:ffff:ffff:ffff:ffff:ffff:ffff
2112ea9:d20::/282ea9:d2f:ffff:ffff:ffff:ffff:ffff:ffff
2122ea9:d30::/282ea9:d3f:ffff:ffff:ffff:ffff:ffff:ffff
2132ea9:d40::/282ea9:d4f:ffff:ffff:ffff:ffff:ffff:ffff
2142ea9:d50::/282ea9:d5f:ffff:ffff:ffff:ffff:ffff:ffff
2152ea9:d60::/282ea9:d6f:ffff:ffff:ffff:ffff:ffff:ffff
2162ea9:d70::/282ea9:d7f:ffff:ffff:ffff:ffff:ffff:ffff
2172ea9:d80::/282ea9:d8f:ffff:ffff:ffff:ffff:ffff:ffff
2182ea9:d90::/282ea9:d9f:ffff:ffff:ffff:ffff:ffff:ffff
2192ea9:da0::/282ea9:daf:ffff:ffff:ffff:ffff:ffff:ffff
2202ea9:db0::/282ea9:dbf:ffff:ffff:ffff:ffff:ffff:ffff
2212ea9:dc0::/282ea9:dcf:ffff:ffff:ffff:ffff:ffff:ffff
2222ea9:dd0::/282ea9:ddf:ffff:ffff:ffff:ffff:ffff:ffff
2232ea9:de0::/282ea9:def:ffff:ffff:ffff:ffff:ffff:ffff
2242ea9:df0::/282ea9:dff:ffff:ffff:ffff:ffff:ffff:ffff
2252ea9:e00::/282ea9:e0f:ffff:ffff:ffff:ffff:ffff:ffff
2262ea9:e10::/282ea9:e1f:ffff:ffff:ffff:ffff:ffff:ffff
2272ea9:e20::/282ea9:e2f:ffff:ffff:ffff:ffff:ffff:ffff
2282ea9:e30::/282ea9:e3f:ffff:ffff:ffff:ffff:ffff:ffff
2292ea9:e40::/282ea9:e4f:ffff:ffff:ffff:ffff:ffff:ffff
2302ea9:e50::/282ea9:e5f:ffff:ffff:ffff:ffff:ffff:ffff
2312ea9:e60::/282ea9:e6f:ffff:ffff:ffff:ffff:ffff:ffff
2322ea9:e70::/282ea9:e7f:ffff:ffff:ffff:ffff:ffff:ffff
2332ea9:e80::/282ea9:e8f:ffff:ffff:ffff:ffff:ffff:ffff
2342ea9:e90::/282ea9:e9f:ffff:ffff:ffff:ffff:ffff:ffff
2352ea9:ea0::/282ea9:eaf:ffff:ffff:ffff:ffff:ffff:ffff
2362ea9:eb0::/282ea9:ebf:ffff:ffff:ffff:ffff:ffff:ffff
2372ea9:ec0::/282ea9:ecf:ffff:ffff:ffff:ffff:ffff:ffff
2382ea9:ed0::/282ea9:edf:ffff:ffff:ffff:ffff:ffff:ffff
2392ea9:ee0::/282ea9:eef:ffff:ffff:ffff:ffff:ffff:ffff
2402ea9:ef0::/282ea9:eff:ffff:ffff:ffff:ffff:ffff:ffff
2412ea9:f00::/282ea9:f0f:ffff:ffff:ffff:ffff:ffff:ffff
2422ea9:f10::/282ea9:f1f:ffff:ffff:ffff:ffff:ffff:ffff
2432ea9:f20::/282ea9:f2f:ffff:ffff:ffff:ffff:ffff:ffff
2442ea9:f30::/282ea9:f3f:ffff:ffff:ffff:ffff:ffff:ffff
2452ea9:f40::/282ea9:f4f:ffff:ffff:ffff:ffff:ffff:ffff
2462ea9:f50::/282ea9:f5f:ffff:ffff:ffff:ffff:ffff:ffff
2472ea9:f60::/282ea9:f6f:ffff:ffff:ffff:ffff:ffff:ffff
2482ea9:f70::/282ea9:f7f:ffff:ffff:ffff:ffff:ffff:ffff
2492ea9:f80::/282ea9:f8f:ffff:ffff:ffff:ffff:ffff:ffff
2502ea9:f90::/282ea9:f9f:ffff:ffff:ffff:ffff:ffff:ffff
2512ea9:fa0::/282ea9:faf:ffff:ffff:ffff:ffff:ffff:ffff
2522ea9:fb0::/282ea9:fbf:ffff:ffff:ffff:ffff:ffff:ffff
2532ea9:fc0::/282ea9:fcf:ffff:ffff:ffff:ffff:ffff:ffff
2542ea9:fd0::/282ea9:fdf:ffff:ffff:ffff:ffff:ffff:ffff
2552ea9:fe0::/282ea9:fef:ffff:ffff:ffff:ffff:ffff:ffff
2562ea9:ff0::/282ea9:fff:ffff: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.