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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
2ce2::/16
First address
2ce2::
Last address
2ce2: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
2ce2:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.e.c.2.ip6.arpa
Split into smaller subnets/28
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

2ce2::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
12ce2::/282ce2:f:ffff:ffff:ffff:ffff:ffff:ffff
22ce2:10::/282ce2:1f:ffff:ffff:ffff:ffff:ffff:ffff
32ce2:20::/282ce2:2f:ffff:ffff:ffff:ffff:ffff:ffff
42ce2:30::/282ce2:3f:ffff:ffff:ffff:ffff:ffff:ffff
52ce2:40::/282ce2:4f:ffff:ffff:ffff:ffff:ffff:ffff
62ce2:50::/282ce2:5f:ffff:ffff:ffff:ffff:ffff:ffff
72ce2:60::/282ce2:6f:ffff:ffff:ffff:ffff:ffff:ffff
82ce2:70::/282ce2:7f:ffff:ffff:ffff:ffff:ffff:ffff
92ce2:80::/282ce2:8f:ffff:ffff:ffff:ffff:ffff:ffff
102ce2:90::/282ce2:9f:ffff:ffff:ffff:ffff:ffff:ffff
112ce2:a0::/282ce2:af:ffff:ffff:ffff:ffff:ffff:ffff
122ce2:b0::/282ce2:bf:ffff:ffff:ffff:ffff:ffff:ffff
132ce2:c0::/282ce2:cf:ffff:ffff:ffff:ffff:ffff:ffff
142ce2:d0::/282ce2:df:ffff:ffff:ffff:ffff:ffff:ffff
152ce2:e0::/282ce2:ef:ffff:ffff:ffff:ffff:ffff:ffff
162ce2:f0::/282ce2:ff:ffff:ffff:ffff:ffff:ffff:ffff
172ce2:100::/282ce2:10f:ffff:ffff:ffff:ffff:ffff:ffff
182ce2:110::/282ce2:11f:ffff:ffff:ffff:ffff:ffff:ffff
192ce2:120::/282ce2:12f:ffff:ffff:ffff:ffff:ffff:ffff
202ce2:130::/282ce2:13f:ffff:ffff:ffff:ffff:ffff:ffff
212ce2:140::/282ce2:14f:ffff:ffff:ffff:ffff:ffff:ffff
222ce2:150::/282ce2:15f:ffff:ffff:ffff:ffff:ffff:ffff
232ce2:160::/282ce2:16f:ffff:ffff:ffff:ffff:ffff:ffff
242ce2:170::/282ce2:17f:ffff:ffff:ffff:ffff:ffff:ffff
252ce2:180::/282ce2:18f:ffff:ffff:ffff:ffff:ffff:ffff
262ce2:190::/282ce2:19f:ffff:ffff:ffff:ffff:ffff:ffff
272ce2:1a0::/282ce2:1af:ffff:ffff:ffff:ffff:ffff:ffff
282ce2:1b0::/282ce2:1bf:ffff:ffff:ffff:ffff:ffff:ffff
292ce2:1c0::/282ce2:1cf:ffff:ffff:ffff:ffff:ffff:ffff
302ce2:1d0::/282ce2:1df:ffff:ffff:ffff:ffff:ffff:ffff
312ce2:1e0::/282ce2:1ef:ffff:ffff:ffff:ffff:ffff:ffff
322ce2:1f0::/282ce2:1ff:ffff:ffff:ffff:ffff:ffff:ffff
332ce2:200::/282ce2:20f:ffff:ffff:ffff:ffff:ffff:ffff
342ce2:210::/282ce2:21f:ffff:ffff:ffff:ffff:ffff:ffff
352ce2:220::/282ce2:22f:ffff:ffff:ffff:ffff:ffff:ffff
362ce2:230::/282ce2:23f:ffff:ffff:ffff:ffff:ffff:ffff
372ce2:240::/282ce2:24f:ffff:ffff:ffff:ffff:ffff:ffff
382ce2:250::/282ce2:25f:ffff:ffff:ffff:ffff:ffff:ffff
392ce2:260::/282ce2:26f:ffff:ffff:ffff:ffff:ffff:ffff
402ce2:270::/282ce2:27f:ffff:ffff:ffff:ffff:ffff:ffff
412ce2:280::/282ce2:28f:ffff:ffff:ffff:ffff:ffff:ffff
422ce2:290::/282ce2:29f:ffff:ffff:ffff:ffff:ffff:ffff
432ce2:2a0::/282ce2:2af:ffff:ffff:ffff:ffff:ffff:ffff
442ce2:2b0::/282ce2:2bf:ffff:ffff:ffff:ffff:ffff:ffff
452ce2:2c0::/282ce2:2cf:ffff:ffff:ffff:ffff:ffff:ffff
462ce2:2d0::/282ce2:2df:ffff:ffff:ffff:ffff:ffff:ffff
472ce2:2e0::/282ce2:2ef:ffff:ffff:ffff:ffff:ffff:ffff
482ce2:2f0::/282ce2:2ff:ffff:ffff:ffff:ffff:ffff:ffff
492ce2:300::/282ce2:30f:ffff:ffff:ffff:ffff:ffff:ffff
502ce2:310::/282ce2:31f:ffff:ffff:ffff:ffff:ffff:ffff
512ce2:320::/282ce2:32f:ffff:ffff:ffff:ffff:ffff:ffff
522ce2:330::/282ce2:33f:ffff:ffff:ffff:ffff:ffff:ffff
532ce2:340::/282ce2:34f:ffff:ffff:ffff:ffff:ffff:ffff
542ce2:350::/282ce2:35f:ffff:ffff:ffff:ffff:ffff:ffff
552ce2:360::/282ce2:36f:ffff:ffff:ffff:ffff:ffff:ffff
562ce2:370::/282ce2:37f:ffff:ffff:ffff:ffff:ffff:ffff
572ce2:380::/282ce2:38f:ffff:ffff:ffff:ffff:ffff:ffff
582ce2:390::/282ce2:39f:ffff:ffff:ffff:ffff:ffff:ffff
592ce2:3a0::/282ce2:3af:ffff:ffff:ffff:ffff:ffff:ffff
602ce2:3b0::/282ce2:3bf:ffff:ffff:ffff:ffff:ffff:ffff
612ce2:3c0::/282ce2:3cf:ffff:ffff:ffff:ffff:ffff:ffff
622ce2:3d0::/282ce2:3df:ffff:ffff:ffff:ffff:ffff:ffff
632ce2:3e0::/282ce2:3ef:ffff:ffff:ffff:ffff:ffff:ffff
642ce2:3f0::/282ce2:3ff:ffff:ffff:ffff:ffff:ffff:ffff
652ce2:400::/282ce2:40f:ffff:ffff:ffff:ffff:ffff:ffff
662ce2:410::/282ce2:41f:ffff:ffff:ffff:ffff:ffff:ffff
672ce2:420::/282ce2:42f:ffff:ffff:ffff:ffff:ffff:ffff
682ce2:430::/282ce2:43f:ffff:ffff:ffff:ffff:ffff:ffff
692ce2:440::/282ce2:44f:ffff:ffff:ffff:ffff:ffff:ffff
702ce2:450::/282ce2:45f:ffff:ffff:ffff:ffff:ffff:ffff
712ce2:460::/282ce2:46f:ffff:ffff:ffff:ffff:ffff:ffff
722ce2:470::/282ce2:47f:ffff:ffff:ffff:ffff:ffff:ffff
732ce2:480::/282ce2:48f:ffff:ffff:ffff:ffff:ffff:ffff
742ce2:490::/282ce2:49f:ffff:ffff:ffff:ffff:ffff:ffff
752ce2:4a0::/282ce2:4af:ffff:ffff:ffff:ffff:ffff:ffff
762ce2:4b0::/282ce2:4bf:ffff:ffff:ffff:ffff:ffff:ffff
772ce2:4c0::/282ce2:4cf:ffff:ffff:ffff:ffff:ffff:ffff
782ce2:4d0::/282ce2:4df:ffff:ffff:ffff:ffff:ffff:ffff
792ce2:4e0::/282ce2:4ef:ffff:ffff:ffff:ffff:ffff:ffff
802ce2:4f0::/282ce2:4ff:ffff:ffff:ffff:ffff:ffff:ffff
812ce2:500::/282ce2:50f:ffff:ffff:ffff:ffff:ffff:ffff
822ce2:510::/282ce2:51f:ffff:ffff:ffff:ffff:ffff:ffff
832ce2:520::/282ce2:52f:ffff:ffff:ffff:ffff:ffff:ffff
842ce2:530::/282ce2:53f:ffff:ffff:ffff:ffff:ffff:ffff
852ce2:540::/282ce2:54f:ffff:ffff:ffff:ffff:ffff:ffff
862ce2:550::/282ce2:55f:ffff:ffff:ffff:ffff:ffff:ffff
872ce2:560::/282ce2:56f:ffff:ffff:ffff:ffff:ffff:ffff
882ce2:570::/282ce2:57f:ffff:ffff:ffff:ffff:ffff:ffff
892ce2:580::/282ce2:58f:ffff:ffff:ffff:ffff:ffff:ffff
902ce2:590::/282ce2:59f:ffff:ffff:ffff:ffff:ffff:ffff
912ce2:5a0::/282ce2:5af:ffff:ffff:ffff:ffff:ffff:ffff
922ce2:5b0::/282ce2:5bf:ffff:ffff:ffff:ffff:ffff:ffff
932ce2:5c0::/282ce2:5cf:ffff:ffff:ffff:ffff:ffff:ffff
942ce2:5d0::/282ce2:5df:ffff:ffff:ffff:ffff:ffff:ffff
952ce2:5e0::/282ce2:5ef:ffff:ffff:ffff:ffff:ffff:ffff
962ce2:5f0::/282ce2:5ff:ffff:ffff:ffff:ffff:ffff:ffff
972ce2:600::/282ce2:60f:ffff:ffff:ffff:ffff:ffff:ffff
982ce2:610::/282ce2:61f:ffff:ffff:ffff:ffff:ffff:ffff
992ce2:620::/282ce2:62f:ffff:ffff:ffff:ffff:ffff:ffff
1002ce2:630::/282ce2:63f:ffff:ffff:ffff:ffff:ffff:ffff
1012ce2:640::/282ce2:64f:ffff:ffff:ffff:ffff:ffff:ffff
1022ce2:650::/282ce2:65f:ffff:ffff:ffff:ffff:ffff:ffff
1032ce2:660::/282ce2:66f:ffff:ffff:ffff:ffff:ffff:ffff
1042ce2:670::/282ce2:67f:ffff:ffff:ffff:ffff:ffff:ffff
1052ce2:680::/282ce2:68f:ffff:ffff:ffff:ffff:ffff:ffff
1062ce2:690::/282ce2:69f:ffff:ffff:ffff:ffff:ffff:ffff
1072ce2:6a0::/282ce2:6af:ffff:ffff:ffff:ffff:ffff:ffff
1082ce2:6b0::/282ce2:6bf:ffff:ffff:ffff:ffff:ffff:ffff
1092ce2:6c0::/282ce2:6cf:ffff:ffff:ffff:ffff:ffff:ffff
1102ce2:6d0::/282ce2:6df:ffff:ffff:ffff:ffff:ffff:ffff
1112ce2:6e0::/282ce2:6ef:ffff:ffff:ffff:ffff:ffff:ffff
1122ce2:6f0::/282ce2:6ff:ffff:ffff:ffff:ffff:ffff:ffff
1132ce2:700::/282ce2:70f:ffff:ffff:ffff:ffff:ffff:ffff
1142ce2:710::/282ce2:71f:ffff:ffff:ffff:ffff:ffff:ffff
1152ce2:720::/282ce2:72f:ffff:ffff:ffff:ffff:ffff:ffff
1162ce2:730::/282ce2:73f:ffff:ffff:ffff:ffff:ffff:ffff
1172ce2:740::/282ce2:74f:ffff:ffff:ffff:ffff:ffff:ffff
1182ce2:750::/282ce2:75f:ffff:ffff:ffff:ffff:ffff:ffff
1192ce2:760::/282ce2:76f:ffff:ffff:ffff:ffff:ffff:ffff
1202ce2:770::/282ce2:77f:ffff:ffff:ffff:ffff:ffff:ffff
1212ce2:780::/282ce2:78f:ffff:ffff:ffff:ffff:ffff:ffff
1222ce2:790::/282ce2:79f:ffff:ffff:ffff:ffff:ffff:ffff
1232ce2:7a0::/282ce2:7af:ffff:ffff:ffff:ffff:ffff:ffff
1242ce2:7b0::/282ce2:7bf:ffff:ffff:ffff:ffff:ffff:ffff
1252ce2:7c0::/282ce2:7cf:ffff:ffff:ffff:ffff:ffff:ffff
1262ce2:7d0::/282ce2:7df:ffff:ffff:ffff:ffff:ffff:ffff
1272ce2:7e0::/282ce2:7ef:ffff:ffff:ffff:ffff:ffff:ffff
1282ce2:7f0::/282ce2:7ff:ffff:ffff:ffff:ffff:ffff:ffff
1292ce2:800::/282ce2:80f:ffff:ffff:ffff:ffff:ffff:ffff
1302ce2:810::/282ce2:81f:ffff:ffff:ffff:ffff:ffff:ffff
1312ce2:820::/282ce2:82f:ffff:ffff:ffff:ffff:ffff:ffff
1322ce2:830::/282ce2:83f:ffff:ffff:ffff:ffff:ffff:ffff
1332ce2:840::/282ce2:84f:ffff:ffff:ffff:ffff:ffff:ffff
1342ce2:850::/282ce2:85f:ffff:ffff:ffff:ffff:ffff:ffff
1352ce2:860::/282ce2:86f:ffff:ffff:ffff:ffff:ffff:ffff
1362ce2:870::/282ce2:87f:ffff:ffff:ffff:ffff:ffff:ffff
1372ce2:880::/282ce2:88f:ffff:ffff:ffff:ffff:ffff:ffff
1382ce2:890::/282ce2:89f:ffff:ffff:ffff:ffff:ffff:ffff
1392ce2:8a0::/282ce2:8af:ffff:ffff:ffff:ffff:ffff:ffff
1402ce2:8b0::/282ce2:8bf:ffff:ffff:ffff:ffff:ffff:ffff
1412ce2:8c0::/282ce2:8cf:ffff:ffff:ffff:ffff:ffff:ffff
1422ce2:8d0::/282ce2:8df:ffff:ffff:ffff:ffff:ffff:ffff
1432ce2:8e0::/282ce2:8ef:ffff:ffff:ffff:ffff:ffff:ffff
1442ce2:8f0::/282ce2:8ff:ffff:ffff:ffff:ffff:ffff:ffff
1452ce2:900::/282ce2:90f:ffff:ffff:ffff:ffff:ffff:ffff
1462ce2:910::/282ce2:91f:ffff:ffff:ffff:ffff:ffff:ffff
1472ce2:920::/282ce2:92f:ffff:ffff:ffff:ffff:ffff:ffff
1482ce2:930::/282ce2:93f:ffff:ffff:ffff:ffff:ffff:ffff
1492ce2:940::/282ce2:94f:ffff:ffff:ffff:ffff:ffff:ffff
1502ce2:950::/282ce2:95f:ffff:ffff:ffff:ffff:ffff:ffff
1512ce2:960::/282ce2:96f:ffff:ffff:ffff:ffff:ffff:ffff
1522ce2:970::/282ce2:97f:ffff:ffff:ffff:ffff:ffff:ffff
1532ce2:980::/282ce2:98f:ffff:ffff:ffff:ffff:ffff:ffff
1542ce2:990::/282ce2:99f:ffff:ffff:ffff:ffff:ffff:ffff
1552ce2:9a0::/282ce2:9af:ffff:ffff:ffff:ffff:ffff:ffff
1562ce2:9b0::/282ce2:9bf:ffff:ffff:ffff:ffff:ffff:ffff
1572ce2:9c0::/282ce2:9cf:ffff:ffff:ffff:ffff:ffff:ffff
1582ce2:9d0::/282ce2:9df:ffff:ffff:ffff:ffff:ffff:ffff
1592ce2:9e0::/282ce2:9ef:ffff:ffff:ffff:ffff:ffff:ffff
1602ce2:9f0::/282ce2:9ff:ffff:ffff:ffff:ffff:ffff:ffff
1612ce2:a00::/282ce2:a0f:ffff:ffff:ffff:ffff:ffff:ffff
1622ce2:a10::/282ce2:a1f:ffff:ffff:ffff:ffff:ffff:ffff
1632ce2:a20::/282ce2:a2f:ffff:ffff:ffff:ffff:ffff:ffff
1642ce2:a30::/282ce2:a3f:ffff:ffff:ffff:ffff:ffff:ffff
1652ce2:a40::/282ce2:a4f:ffff:ffff:ffff:ffff:ffff:ffff
1662ce2:a50::/282ce2:a5f:ffff:ffff:ffff:ffff:ffff:ffff
1672ce2:a60::/282ce2:a6f:ffff:ffff:ffff:ffff:ffff:ffff
1682ce2:a70::/282ce2:a7f:ffff:ffff:ffff:ffff:ffff:ffff
1692ce2:a80::/282ce2:a8f:ffff:ffff:ffff:ffff:ffff:ffff
1702ce2:a90::/282ce2:a9f:ffff:ffff:ffff:ffff:ffff:ffff
1712ce2:aa0::/282ce2:aaf:ffff:ffff:ffff:ffff:ffff:ffff
1722ce2:ab0::/282ce2:abf:ffff:ffff:ffff:ffff:ffff:ffff
1732ce2:ac0::/282ce2:acf:ffff:ffff:ffff:ffff:ffff:ffff
1742ce2:ad0::/282ce2:adf:ffff:ffff:ffff:ffff:ffff:ffff
1752ce2:ae0::/282ce2:aef:ffff:ffff:ffff:ffff:ffff:ffff
1762ce2:af0::/282ce2:aff:ffff:ffff:ffff:ffff:ffff:ffff
1772ce2:b00::/282ce2:b0f:ffff:ffff:ffff:ffff:ffff:ffff
1782ce2:b10::/282ce2:b1f:ffff:ffff:ffff:ffff:ffff:ffff
1792ce2:b20::/282ce2:b2f:ffff:ffff:ffff:ffff:ffff:ffff
1802ce2:b30::/282ce2:b3f:ffff:ffff:ffff:ffff:ffff:ffff
1812ce2:b40::/282ce2:b4f:ffff:ffff:ffff:ffff:ffff:ffff
1822ce2:b50::/282ce2:b5f:ffff:ffff:ffff:ffff:ffff:ffff
1832ce2:b60::/282ce2:b6f:ffff:ffff:ffff:ffff:ffff:ffff
1842ce2:b70::/282ce2:b7f:ffff:ffff:ffff:ffff:ffff:ffff
1852ce2:b80::/282ce2:b8f:ffff:ffff:ffff:ffff:ffff:ffff
1862ce2:b90::/282ce2:b9f:ffff:ffff:ffff:ffff:ffff:ffff
1872ce2:ba0::/282ce2:baf:ffff:ffff:ffff:ffff:ffff:ffff
1882ce2:bb0::/282ce2:bbf:ffff:ffff:ffff:ffff:ffff:ffff
1892ce2:bc0::/282ce2:bcf:ffff:ffff:ffff:ffff:ffff:ffff
1902ce2:bd0::/282ce2:bdf:ffff:ffff:ffff:ffff:ffff:ffff
1912ce2:be0::/282ce2:bef:ffff:ffff:ffff:ffff:ffff:ffff
1922ce2:bf0::/282ce2:bff:ffff:ffff:ffff:ffff:ffff:ffff
1932ce2:c00::/282ce2:c0f:ffff:ffff:ffff:ffff:ffff:ffff
1942ce2:c10::/282ce2:c1f:ffff:ffff:ffff:ffff:ffff:ffff
1952ce2:c20::/282ce2:c2f:ffff:ffff:ffff:ffff:ffff:ffff
1962ce2:c30::/282ce2:c3f:ffff:ffff:ffff:ffff:ffff:ffff
1972ce2:c40::/282ce2:c4f:ffff:ffff:ffff:ffff:ffff:ffff
1982ce2:c50::/282ce2:c5f:ffff:ffff:ffff:ffff:ffff:ffff
1992ce2:c60::/282ce2:c6f:ffff:ffff:ffff:ffff:ffff:ffff
2002ce2:c70::/282ce2:c7f:ffff:ffff:ffff:ffff:ffff:ffff
2012ce2:c80::/282ce2:c8f:ffff:ffff:ffff:ffff:ffff:ffff
2022ce2:c90::/282ce2:c9f:ffff:ffff:ffff:ffff:ffff:ffff
2032ce2:ca0::/282ce2:caf:ffff:ffff:ffff:ffff:ffff:ffff
2042ce2:cb0::/282ce2:cbf:ffff:ffff:ffff:ffff:ffff:ffff
2052ce2:cc0::/282ce2:ccf:ffff:ffff:ffff:ffff:ffff:ffff
2062ce2:cd0::/282ce2:cdf:ffff:ffff:ffff:ffff:ffff:ffff
2072ce2:ce0::/282ce2:cef:ffff:ffff:ffff:ffff:ffff:ffff
2082ce2:cf0::/282ce2:cff:ffff:ffff:ffff:ffff:ffff:ffff
2092ce2:d00::/282ce2:d0f:ffff:ffff:ffff:ffff:ffff:ffff
2102ce2:d10::/282ce2:d1f:ffff:ffff:ffff:ffff:ffff:ffff
2112ce2:d20::/282ce2:d2f:ffff:ffff:ffff:ffff:ffff:ffff
2122ce2:d30::/282ce2:d3f:ffff:ffff:ffff:ffff:ffff:ffff
2132ce2:d40::/282ce2:d4f:ffff:ffff:ffff:ffff:ffff:ffff
2142ce2:d50::/282ce2:d5f:ffff:ffff:ffff:ffff:ffff:ffff
2152ce2:d60::/282ce2:d6f:ffff:ffff:ffff:ffff:ffff:ffff
2162ce2:d70::/282ce2:d7f:ffff:ffff:ffff:ffff:ffff:ffff
2172ce2:d80::/282ce2:d8f:ffff:ffff:ffff:ffff:ffff:ffff
2182ce2:d90::/282ce2:d9f:ffff:ffff:ffff:ffff:ffff:ffff
2192ce2:da0::/282ce2:daf:ffff:ffff:ffff:ffff:ffff:ffff
2202ce2:db0::/282ce2:dbf:ffff:ffff:ffff:ffff:ffff:ffff
2212ce2:dc0::/282ce2:dcf:ffff:ffff:ffff:ffff:ffff:ffff
2222ce2:dd0::/282ce2:ddf:ffff:ffff:ffff:ffff:ffff:ffff
2232ce2:de0::/282ce2:def:ffff:ffff:ffff:ffff:ffff:ffff
2242ce2:df0::/282ce2:dff:ffff:ffff:ffff:ffff:ffff:ffff
2252ce2:e00::/282ce2:e0f:ffff:ffff:ffff:ffff:ffff:ffff
2262ce2:e10::/282ce2:e1f:ffff:ffff:ffff:ffff:ffff:ffff
2272ce2:e20::/282ce2:e2f:ffff:ffff:ffff:ffff:ffff:ffff
2282ce2:e30::/282ce2:e3f:ffff:ffff:ffff:ffff:ffff:ffff
2292ce2:e40::/282ce2:e4f:ffff:ffff:ffff:ffff:ffff:ffff
2302ce2:e50::/282ce2:e5f:ffff:ffff:ffff:ffff:ffff:ffff
2312ce2:e60::/282ce2:e6f:ffff:ffff:ffff:ffff:ffff:ffff
2322ce2:e70::/282ce2:e7f:ffff:ffff:ffff:ffff:ffff:ffff
2332ce2:e80::/282ce2:e8f:ffff:ffff:ffff:ffff:ffff:ffff
2342ce2:e90::/282ce2:e9f:ffff:ffff:ffff:ffff:ffff:ffff
2352ce2:ea0::/282ce2:eaf:ffff:ffff:ffff:ffff:ffff:ffff
2362ce2:eb0::/282ce2:ebf:ffff:ffff:ffff:ffff:ffff:ffff
2372ce2:ec0::/282ce2:ecf:ffff:ffff:ffff:ffff:ffff:ffff
2382ce2:ed0::/282ce2:edf:ffff:ffff:ffff:ffff:ffff:ffff
2392ce2:ee0::/282ce2:eef:ffff:ffff:ffff:ffff:ffff:ffff
2402ce2:ef0::/282ce2:eff:ffff:ffff:ffff:ffff:ffff:ffff
2412ce2:f00::/282ce2:f0f:ffff:ffff:ffff:ffff:ffff:ffff
2422ce2:f10::/282ce2:f1f:ffff:ffff:ffff:ffff:ffff:ffff
2432ce2:f20::/282ce2:f2f:ffff:ffff:ffff:ffff:ffff:ffff
2442ce2:f30::/282ce2:f3f:ffff:ffff:ffff:ffff:ffff:ffff
2452ce2:f40::/282ce2:f4f:ffff:ffff:ffff:ffff:ffff:ffff
2462ce2:f50::/282ce2:f5f:ffff:ffff:ffff:ffff:ffff:ffff
2472ce2:f60::/282ce2:f6f:ffff:ffff:ffff:ffff:ffff:ffff
2482ce2:f70::/282ce2:f7f:ffff:ffff:ffff:ffff:ffff:ffff
2492ce2:f80::/282ce2:f8f:ffff:ffff:ffff:ffff:ffff:ffff
2502ce2:f90::/282ce2:f9f:ffff:ffff:ffff:ffff:ffff:ffff
2512ce2:fa0::/282ce2:faf:ffff:ffff:ffff:ffff:ffff:ffff
2522ce2:fb0::/282ce2:fbf:ffff:ffff:ffff:ffff:ffff:ffff
2532ce2:fc0::/282ce2:fcf:ffff:ffff:ffff:ffff:ffff:ffff
2542ce2:fd0::/282ce2:fdf:ffff:ffff:ffff:ffff:ffff:ffff
2552ce2:fe0::/282ce2:fef:ffff:ffff:ffff:ffff:ffff:ffff
2562ce2:ff0::/282ce2: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.