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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/12
Addresses2^116
/64 networks2^52
Network
2ea0::/12
First address
2ea0::
Last address
2eaf:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
83,076,749,736,557,242,056,487,941,267,521,536 (2^116)
/64 networks (LANs)
4,503,599,627,370,496 (2^52)
Full form
2ea0:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
a.e.2.ip6.arpa
Split into smaller subnets/28
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2ea0::/12 makes 65,536 subnets of /28; the first 256 are listed.

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