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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
2ee3::/16
First address
2ee3::
Last address
2ee3: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
2ee3:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.e.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)

2ee3::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
12ee3::/282ee3:f:ffff:ffff:ffff:ffff:ffff:ffff
22ee3:10::/282ee3:1f:ffff:ffff:ffff:ffff:ffff:ffff
32ee3:20::/282ee3:2f:ffff:ffff:ffff:ffff:ffff:ffff
42ee3:30::/282ee3:3f:ffff:ffff:ffff:ffff:ffff:ffff
52ee3:40::/282ee3:4f:ffff:ffff:ffff:ffff:ffff:ffff
62ee3:50::/282ee3:5f:ffff:ffff:ffff:ffff:ffff:ffff
72ee3:60::/282ee3:6f:ffff:ffff:ffff:ffff:ffff:ffff
82ee3:70::/282ee3:7f:ffff:ffff:ffff:ffff:ffff:ffff
92ee3:80::/282ee3:8f:ffff:ffff:ffff:ffff:ffff:ffff
102ee3:90::/282ee3:9f:ffff:ffff:ffff:ffff:ffff:ffff
112ee3:a0::/282ee3:af:ffff:ffff:ffff:ffff:ffff:ffff
122ee3:b0::/282ee3:bf:ffff:ffff:ffff:ffff:ffff:ffff
132ee3:c0::/282ee3:cf:ffff:ffff:ffff:ffff:ffff:ffff
142ee3:d0::/282ee3:df:ffff:ffff:ffff:ffff:ffff:ffff
152ee3:e0::/282ee3:ef:ffff:ffff:ffff:ffff:ffff:ffff
162ee3:f0::/282ee3:ff:ffff:ffff:ffff:ffff:ffff:ffff
172ee3:100::/282ee3:10f:ffff:ffff:ffff:ffff:ffff:ffff
182ee3:110::/282ee3:11f:ffff:ffff:ffff:ffff:ffff:ffff
192ee3:120::/282ee3:12f:ffff:ffff:ffff:ffff:ffff:ffff
202ee3:130::/282ee3:13f:ffff:ffff:ffff:ffff:ffff:ffff
212ee3:140::/282ee3:14f:ffff:ffff:ffff:ffff:ffff:ffff
222ee3:150::/282ee3:15f:ffff:ffff:ffff:ffff:ffff:ffff
232ee3:160::/282ee3:16f:ffff:ffff:ffff:ffff:ffff:ffff
242ee3:170::/282ee3:17f:ffff:ffff:ffff:ffff:ffff:ffff
252ee3:180::/282ee3:18f:ffff:ffff:ffff:ffff:ffff:ffff
262ee3:190::/282ee3:19f:ffff:ffff:ffff:ffff:ffff:ffff
272ee3:1a0::/282ee3:1af:ffff:ffff:ffff:ffff:ffff:ffff
282ee3:1b0::/282ee3:1bf:ffff:ffff:ffff:ffff:ffff:ffff
292ee3:1c0::/282ee3:1cf:ffff:ffff:ffff:ffff:ffff:ffff
302ee3:1d0::/282ee3:1df:ffff:ffff:ffff:ffff:ffff:ffff
312ee3:1e0::/282ee3:1ef:ffff:ffff:ffff:ffff:ffff:ffff
322ee3:1f0::/282ee3:1ff:ffff:ffff:ffff:ffff:ffff:ffff
332ee3:200::/282ee3:20f:ffff:ffff:ffff:ffff:ffff:ffff
342ee3:210::/282ee3:21f:ffff:ffff:ffff:ffff:ffff:ffff
352ee3:220::/282ee3:22f:ffff:ffff:ffff:ffff:ffff:ffff
362ee3:230::/282ee3:23f:ffff:ffff:ffff:ffff:ffff:ffff
372ee3:240::/282ee3:24f:ffff:ffff:ffff:ffff:ffff:ffff
382ee3:250::/282ee3:25f:ffff:ffff:ffff:ffff:ffff:ffff
392ee3:260::/282ee3:26f:ffff:ffff:ffff:ffff:ffff:ffff
402ee3:270::/282ee3:27f:ffff:ffff:ffff:ffff:ffff:ffff
412ee3:280::/282ee3:28f:ffff:ffff:ffff:ffff:ffff:ffff
422ee3:290::/282ee3:29f:ffff:ffff:ffff:ffff:ffff:ffff
432ee3:2a0::/282ee3:2af:ffff:ffff:ffff:ffff:ffff:ffff
442ee3:2b0::/282ee3:2bf:ffff:ffff:ffff:ffff:ffff:ffff
452ee3:2c0::/282ee3:2cf:ffff:ffff:ffff:ffff:ffff:ffff
462ee3:2d0::/282ee3:2df:ffff:ffff:ffff:ffff:ffff:ffff
472ee3:2e0::/282ee3:2ef:ffff:ffff:ffff:ffff:ffff:ffff
482ee3:2f0::/282ee3:2ff:ffff:ffff:ffff:ffff:ffff:ffff
492ee3:300::/282ee3:30f:ffff:ffff:ffff:ffff:ffff:ffff
502ee3:310::/282ee3:31f:ffff:ffff:ffff:ffff:ffff:ffff
512ee3:320::/282ee3:32f:ffff:ffff:ffff:ffff:ffff:ffff
522ee3:330::/282ee3:33f:ffff:ffff:ffff:ffff:ffff:ffff
532ee3:340::/282ee3:34f:ffff:ffff:ffff:ffff:ffff:ffff
542ee3:350::/282ee3:35f:ffff:ffff:ffff:ffff:ffff:ffff
552ee3:360::/282ee3:36f:ffff:ffff:ffff:ffff:ffff:ffff
562ee3:370::/282ee3:37f:ffff:ffff:ffff:ffff:ffff:ffff
572ee3:380::/282ee3:38f:ffff:ffff:ffff:ffff:ffff:ffff
582ee3:390::/282ee3:39f:ffff:ffff:ffff:ffff:ffff:ffff
592ee3:3a0::/282ee3:3af:ffff:ffff:ffff:ffff:ffff:ffff
602ee3:3b0::/282ee3:3bf:ffff:ffff:ffff:ffff:ffff:ffff
612ee3:3c0::/282ee3:3cf:ffff:ffff:ffff:ffff:ffff:ffff
622ee3:3d0::/282ee3:3df:ffff:ffff:ffff:ffff:ffff:ffff
632ee3:3e0::/282ee3:3ef:ffff:ffff:ffff:ffff:ffff:ffff
642ee3:3f0::/282ee3:3ff:ffff:ffff:ffff:ffff:ffff:ffff
652ee3:400::/282ee3:40f:ffff:ffff:ffff:ffff:ffff:ffff
662ee3:410::/282ee3:41f:ffff:ffff:ffff:ffff:ffff:ffff
672ee3:420::/282ee3:42f:ffff:ffff:ffff:ffff:ffff:ffff
682ee3:430::/282ee3:43f:ffff:ffff:ffff:ffff:ffff:ffff
692ee3:440::/282ee3:44f:ffff:ffff:ffff:ffff:ffff:ffff
702ee3:450::/282ee3:45f:ffff:ffff:ffff:ffff:ffff:ffff
712ee3:460::/282ee3:46f:ffff:ffff:ffff:ffff:ffff:ffff
722ee3:470::/282ee3:47f:ffff:ffff:ffff:ffff:ffff:ffff
732ee3:480::/282ee3:48f:ffff:ffff:ffff:ffff:ffff:ffff
742ee3:490::/282ee3:49f:ffff:ffff:ffff:ffff:ffff:ffff
752ee3:4a0::/282ee3:4af:ffff:ffff:ffff:ffff:ffff:ffff
762ee3:4b0::/282ee3:4bf:ffff:ffff:ffff:ffff:ffff:ffff
772ee3:4c0::/282ee3:4cf:ffff:ffff:ffff:ffff:ffff:ffff
782ee3:4d0::/282ee3:4df:ffff:ffff:ffff:ffff:ffff:ffff
792ee3:4e0::/282ee3:4ef:ffff:ffff:ffff:ffff:ffff:ffff
802ee3:4f0::/282ee3:4ff:ffff:ffff:ffff:ffff:ffff:ffff
812ee3:500::/282ee3:50f:ffff:ffff:ffff:ffff:ffff:ffff
822ee3:510::/282ee3:51f:ffff:ffff:ffff:ffff:ffff:ffff
832ee3:520::/282ee3:52f:ffff:ffff:ffff:ffff:ffff:ffff
842ee3:530::/282ee3:53f:ffff:ffff:ffff:ffff:ffff:ffff
852ee3:540::/282ee3:54f:ffff:ffff:ffff:ffff:ffff:ffff
862ee3:550::/282ee3:55f:ffff:ffff:ffff:ffff:ffff:ffff
872ee3:560::/282ee3:56f:ffff:ffff:ffff:ffff:ffff:ffff
882ee3:570::/282ee3:57f:ffff:ffff:ffff:ffff:ffff:ffff
892ee3:580::/282ee3:58f:ffff:ffff:ffff:ffff:ffff:ffff
902ee3:590::/282ee3:59f:ffff:ffff:ffff:ffff:ffff:ffff
912ee3:5a0::/282ee3:5af:ffff:ffff:ffff:ffff:ffff:ffff
922ee3:5b0::/282ee3:5bf:ffff:ffff:ffff:ffff:ffff:ffff
932ee3:5c0::/282ee3:5cf:ffff:ffff:ffff:ffff:ffff:ffff
942ee3:5d0::/282ee3:5df:ffff:ffff:ffff:ffff:ffff:ffff
952ee3:5e0::/282ee3:5ef:ffff:ffff:ffff:ffff:ffff:ffff
962ee3:5f0::/282ee3:5ff:ffff:ffff:ffff:ffff:ffff:ffff
972ee3:600::/282ee3:60f:ffff:ffff:ffff:ffff:ffff:ffff
982ee3:610::/282ee3:61f:ffff:ffff:ffff:ffff:ffff:ffff
992ee3:620::/282ee3:62f:ffff:ffff:ffff:ffff:ffff:ffff
1002ee3:630::/282ee3:63f:ffff:ffff:ffff:ffff:ffff:ffff
1012ee3:640::/282ee3:64f:ffff:ffff:ffff:ffff:ffff:ffff
1022ee3:650::/282ee3:65f:ffff:ffff:ffff:ffff:ffff:ffff
1032ee3:660::/282ee3:66f:ffff:ffff:ffff:ffff:ffff:ffff
1042ee3:670::/282ee3:67f:ffff:ffff:ffff:ffff:ffff:ffff
1052ee3:680::/282ee3:68f:ffff:ffff:ffff:ffff:ffff:ffff
1062ee3:690::/282ee3:69f:ffff:ffff:ffff:ffff:ffff:ffff
1072ee3:6a0::/282ee3:6af:ffff:ffff:ffff:ffff:ffff:ffff
1082ee3:6b0::/282ee3:6bf:ffff:ffff:ffff:ffff:ffff:ffff
1092ee3:6c0::/282ee3:6cf:ffff:ffff:ffff:ffff:ffff:ffff
1102ee3:6d0::/282ee3:6df:ffff:ffff:ffff:ffff:ffff:ffff
1112ee3:6e0::/282ee3:6ef:ffff:ffff:ffff:ffff:ffff:ffff
1122ee3:6f0::/282ee3:6ff:ffff:ffff:ffff:ffff:ffff:ffff
1132ee3:700::/282ee3:70f:ffff:ffff:ffff:ffff:ffff:ffff
1142ee3:710::/282ee3:71f:ffff:ffff:ffff:ffff:ffff:ffff
1152ee3:720::/282ee3:72f:ffff:ffff:ffff:ffff:ffff:ffff
1162ee3:730::/282ee3:73f:ffff:ffff:ffff:ffff:ffff:ffff
1172ee3:740::/282ee3:74f:ffff:ffff:ffff:ffff:ffff:ffff
1182ee3:750::/282ee3:75f:ffff:ffff:ffff:ffff:ffff:ffff
1192ee3:760::/282ee3:76f:ffff:ffff:ffff:ffff:ffff:ffff
1202ee3:770::/282ee3:77f:ffff:ffff:ffff:ffff:ffff:ffff
1212ee3:780::/282ee3:78f:ffff:ffff:ffff:ffff:ffff:ffff
1222ee3:790::/282ee3:79f:ffff:ffff:ffff:ffff:ffff:ffff
1232ee3:7a0::/282ee3:7af:ffff:ffff:ffff:ffff:ffff:ffff
1242ee3:7b0::/282ee3:7bf:ffff:ffff:ffff:ffff:ffff:ffff
1252ee3:7c0::/282ee3:7cf:ffff:ffff:ffff:ffff:ffff:ffff
1262ee3:7d0::/282ee3:7df:ffff:ffff:ffff:ffff:ffff:ffff
1272ee3:7e0::/282ee3:7ef:ffff:ffff:ffff:ffff:ffff:ffff
1282ee3:7f0::/282ee3:7ff:ffff:ffff:ffff:ffff:ffff:ffff
1292ee3:800::/282ee3:80f:ffff:ffff:ffff:ffff:ffff:ffff
1302ee3:810::/282ee3:81f:ffff:ffff:ffff:ffff:ffff:ffff
1312ee3:820::/282ee3:82f:ffff:ffff:ffff:ffff:ffff:ffff
1322ee3:830::/282ee3:83f:ffff:ffff:ffff:ffff:ffff:ffff
1332ee3:840::/282ee3:84f:ffff:ffff:ffff:ffff:ffff:ffff
1342ee3:850::/282ee3:85f:ffff:ffff:ffff:ffff:ffff:ffff
1352ee3:860::/282ee3:86f:ffff:ffff:ffff:ffff:ffff:ffff
1362ee3:870::/282ee3:87f:ffff:ffff:ffff:ffff:ffff:ffff
1372ee3:880::/282ee3:88f:ffff:ffff:ffff:ffff:ffff:ffff
1382ee3:890::/282ee3:89f:ffff:ffff:ffff:ffff:ffff:ffff
1392ee3:8a0::/282ee3:8af:ffff:ffff:ffff:ffff:ffff:ffff
1402ee3:8b0::/282ee3:8bf:ffff:ffff:ffff:ffff:ffff:ffff
1412ee3:8c0::/282ee3:8cf:ffff:ffff:ffff:ffff:ffff:ffff
1422ee3:8d0::/282ee3:8df:ffff:ffff:ffff:ffff:ffff:ffff
1432ee3:8e0::/282ee3:8ef:ffff:ffff:ffff:ffff:ffff:ffff
1442ee3:8f0::/282ee3:8ff:ffff:ffff:ffff:ffff:ffff:ffff
1452ee3:900::/282ee3:90f:ffff:ffff:ffff:ffff:ffff:ffff
1462ee3:910::/282ee3:91f:ffff:ffff:ffff:ffff:ffff:ffff
1472ee3:920::/282ee3:92f:ffff:ffff:ffff:ffff:ffff:ffff
1482ee3:930::/282ee3:93f:ffff:ffff:ffff:ffff:ffff:ffff
1492ee3:940::/282ee3:94f:ffff:ffff:ffff:ffff:ffff:ffff
1502ee3:950::/282ee3:95f:ffff:ffff:ffff:ffff:ffff:ffff
1512ee3:960::/282ee3:96f:ffff:ffff:ffff:ffff:ffff:ffff
1522ee3:970::/282ee3:97f:ffff:ffff:ffff:ffff:ffff:ffff
1532ee3:980::/282ee3:98f:ffff:ffff:ffff:ffff:ffff:ffff
1542ee3:990::/282ee3:99f:ffff:ffff:ffff:ffff:ffff:ffff
1552ee3:9a0::/282ee3:9af:ffff:ffff:ffff:ffff:ffff:ffff
1562ee3:9b0::/282ee3:9bf:ffff:ffff:ffff:ffff:ffff:ffff
1572ee3:9c0::/282ee3:9cf:ffff:ffff:ffff:ffff:ffff:ffff
1582ee3:9d0::/282ee3:9df:ffff:ffff:ffff:ffff:ffff:ffff
1592ee3:9e0::/282ee3:9ef:ffff:ffff:ffff:ffff:ffff:ffff
1602ee3:9f0::/282ee3:9ff:ffff:ffff:ffff:ffff:ffff:ffff
1612ee3:a00::/282ee3:a0f:ffff:ffff:ffff:ffff:ffff:ffff
1622ee3:a10::/282ee3:a1f:ffff:ffff:ffff:ffff:ffff:ffff
1632ee3:a20::/282ee3:a2f:ffff:ffff:ffff:ffff:ffff:ffff
1642ee3:a30::/282ee3:a3f:ffff:ffff:ffff:ffff:ffff:ffff
1652ee3:a40::/282ee3:a4f:ffff:ffff:ffff:ffff:ffff:ffff
1662ee3:a50::/282ee3:a5f:ffff:ffff:ffff:ffff:ffff:ffff
1672ee3:a60::/282ee3:a6f:ffff:ffff:ffff:ffff:ffff:ffff
1682ee3:a70::/282ee3:a7f:ffff:ffff:ffff:ffff:ffff:ffff
1692ee3:a80::/282ee3:a8f:ffff:ffff:ffff:ffff:ffff:ffff
1702ee3:a90::/282ee3:a9f:ffff:ffff:ffff:ffff:ffff:ffff
1712ee3:aa0::/282ee3:aaf:ffff:ffff:ffff:ffff:ffff:ffff
1722ee3:ab0::/282ee3:abf:ffff:ffff:ffff:ffff:ffff:ffff
1732ee3:ac0::/282ee3:acf:ffff:ffff:ffff:ffff:ffff:ffff
1742ee3:ad0::/282ee3:adf:ffff:ffff:ffff:ffff:ffff:ffff
1752ee3:ae0::/282ee3:aef:ffff:ffff:ffff:ffff:ffff:ffff
1762ee3:af0::/282ee3:aff:ffff:ffff:ffff:ffff:ffff:ffff
1772ee3:b00::/282ee3:b0f:ffff:ffff:ffff:ffff:ffff:ffff
1782ee3:b10::/282ee3:b1f:ffff:ffff:ffff:ffff:ffff:ffff
1792ee3:b20::/282ee3:b2f:ffff:ffff:ffff:ffff:ffff:ffff
1802ee3:b30::/282ee3:b3f:ffff:ffff:ffff:ffff:ffff:ffff
1812ee3:b40::/282ee3:b4f:ffff:ffff:ffff:ffff:ffff:ffff
1822ee3:b50::/282ee3:b5f:ffff:ffff:ffff:ffff:ffff:ffff
1832ee3:b60::/282ee3:b6f:ffff:ffff:ffff:ffff:ffff:ffff
1842ee3:b70::/282ee3:b7f:ffff:ffff:ffff:ffff:ffff:ffff
1852ee3:b80::/282ee3:b8f:ffff:ffff:ffff:ffff:ffff:ffff
1862ee3:b90::/282ee3:b9f:ffff:ffff:ffff:ffff:ffff:ffff
1872ee3:ba0::/282ee3:baf:ffff:ffff:ffff:ffff:ffff:ffff
1882ee3:bb0::/282ee3:bbf:ffff:ffff:ffff:ffff:ffff:ffff
1892ee3:bc0::/282ee3:bcf:ffff:ffff:ffff:ffff:ffff:ffff
1902ee3:bd0::/282ee3:bdf:ffff:ffff:ffff:ffff:ffff:ffff
1912ee3:be0::/282ee3:bef:ffff:ffff:ffff:ffff:ffff:ffff
1922ee3:bf0::/282ee3:bff:ffff:ffff:ffff:ffff:ffff:ffff
1932ee3:c00::/282ee3:c0f:ffff:ffff:ffff:ffff:ffff:ffff
1942ee3:c10::/282ee3:c1f:ffff:ffff:ffff:ffff:ffff:ffff
1952ee3:c20::/282ee3:c2f:ffff:ffff:ffff:ffff:ffff:ffff
1962ee3:c30::/282ee3:c3f:ffff:ffff:ffff:ffff:ffff:ffff
1972ee3:c40::/282ee3:c4f:ffff:ffff:ffff:ffff:ffff:ffff
1982ee3:c50::/282ee3:c5f:ffff:ffff:ffff:ffff:ffff:ffff
1992ee3:c60::/282ee3:c6f:ffff:ffff:ffff:ffff:ffff:ffff
2002ee3:c70::/282ee3:c7f:ffff:ffff:ffff:ffff:ffff:ffff
2012ee3:c80::/282ee3:c8f:ffff:ffff:ffff:ffff:ffff:ffff
2022ee3:c90::/282ee3:c9f:ffff:ffff:ffff:ffff:ffff:ffff
2032ee3:ca0::/282ee3:caf:ffff:ffff:ffff:ffff:ffff:ffff
2042ee3:cb0::/282ee3:cbf:ffff:ffff:ffff:ffff:ffff:ffff
2052ee3:cc0::/282ee3:ccf:ffff:ffff:ffff:ffff:ffff:ffff
2062ee3:cd0::/282ee3:cdf:ffff:ffff:ffff:ffff:ffff:ffff
2072ee3:ce0::/282ee3:cef:ffff:ffff:ffff:ffff:ffff:ffff
2082ee3:cf0::/282ee3:cff:ffff:ffff:ffff:ffff:ffff:ffff
2092ee3:d00::/282ee3:d0f:ffff:ffff:ffff:ffff:ffff:ffff
2102ee3:d10::/282ee3:d1f:ffff:ffff:ffff:ffff:ffff:ffff
2112ee3:d20::/282ee3:d2f:ffff:ffff:ffff:ffff:ffff:ffff
2122ee3:d30::/282ee3:d3f:ffff:ffff:ffff:ffff:ffff:ffff
2132ee3:d40::/282ee3:d4f:ffff:ffff:ffff:ffff:ffff:ffff
2142ee3:d50::/282ee3:d5f:ffff:ffff:ffff:ffff:ffff:ffff
2152ee3:d60::/282ee3:d6f:ffff:ffff:ffff:ffff:ffff:ffff
2162ee3:d70::/282ee3:d7f:ffff:ffff:ffff:ffff:ffff:ffff
2172ee3:d80::/282ee3:d8f:ffff:ffff:ffff:ffff:ffff:ffff
2182ee3:d90::/282ee3:d9f:ffff:ffff:ffff:ffff:ffff:ffff
2192ee3:da0::/282ee3:daf:ffff:ffff:ffff:ffff:ffff:ffff
2202ee3:db0::/282ee3:dbf:ffff:ffff:ffff:ffff:ffff:ffff
2212ee3:dc0::/282ee3:dcf:ffff:ffff:ffff:ffff:ffff:ffff
2222ee3:dd0::/282ee3:ddf:ffff:ffff:ffff:ffff:ffff:ffff
2232ee3:de0::/282ee3:def:ffff:ffff:ffff:ffff:ffff:ffff
2242ee3:df0::/282ee3:dff:ffff:ffff:ffff:ffff:ffff:ffff
2252ee3:e00::/282ee3:e0f:ffff:ffff:ffff:ffff:ffff:ffff
2262ee3:e10::/282ee3:e1f:ffff:ffff:ffff:ffff:ffff:ffff
2272ee3:e20::/282ee3:e2f:ffff:ffff:ffff:ffff:ffff:ffff
2282ee3:e30::/282ee3:e3f:ffff:ffff:ffff:ffff:ffff:ffff
2292ee3:e40::/282ee3:e4f:ffff:ffff:ffff:ffff:ffff:ffff
2302ee3:e50::/282ee3:e5f:ffff:ffff:ffff:ffff:ffff:ffff
2312ee3:e60::/282ee3:e6f:ffff:ffff:ffff:ffff:ffff:ffff
2322ee3:e70::/282ee3:e7f:ffff:ffff:ffff:ffff:ffff:ffff
2332ee3:e80::/282ee3:e8f:ffff:ffff:ffff:ffff:ffff:ffff
2342ee3:e90::/282ee3:e9f:ffff:ffff:ffff:ffff:ffff:ffff
2352ee3:ea0::/282ee3:eaf:ffff:ffff:ffff:ffff:ffff:ffff
2362ee3:eb0::/282ee3:ebf:ffff:ffff:ffff:ffff:ffff:ffff
2372ee3:ec0::/282ee3:ecf:ffff:ffff:ffff:ffff:ffff:ffff
2382ee3:ed0::/282ee3:edf:ffff:ffff:ffff:ffff:ffff:ffff
2392ee3:ee0::/282ee3:eef:ffff:ffff:ffff:ffff:ffff:ffff
2402ee3:ef0::/282ee3:eff:ffff:ffff:ffff:ffff:ffff:ffff
2412ee3:f00::/282ee3:f0f:ffff:ffff:ffff:ffff:ffff:ffff
2422ee3:f10::/282ee3:f1f:ffff:ffff:ffff:ffff:ffff:ffff
2432ee3:f20::/282ee3:f2f:ffff:ffff:ffff:ffff:ffff:ffff
2442ee3:f30::/282ee3:f3f:ffff:ffff:ffff:ffff:ffff:ffff
2452ee3:f40::/282ee3:f4f:ffff:ffff:ffff:ffff:ffff:ffff
2462ee3:f50::/282ee3:f5f:ffff:ffff:ffff:ffff:ffff:ffff
2472ee3:f60::/282ee3:f6f:ffff:ffff:ffff:ffff:ffff:ffff
2482ee3:f70::/282ee3:f7f:ffff:ffff:ffff:ffff:ffff:ffff
2492ee3:f80::/282ee3:f8f:ffff:ffff:ffff:ffff:ffff:ffff
2502ee3:f90::/282ee3:f9f:ffff:ffff:ffff:ffff:ffff:ffff
2512ee3:fa0::/282ee3:faf:ffff:ffff:ffff:ffff:ffff:ffff
2522ee3:fb0::/282ee3:fbf:ffff:ffff:ffff:ffff:ffff:ffff
2532ee3:fc0::/282ee3:fcf:ffff:ffff:ffff:ffff:ffff:ffff
2542ee3:fd0::/282ee3:fdf:ffff:ffff:ffff:ffff:ffff:ffff
2552ee3:fe0::/282ee3:fef:ffff:ffff:ffff:ffff:ffff:ffff
2562ee3:ff0::/282ee3: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.