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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
2ed2::/16
First address
2ed2::
Last address
2ed2: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
2ed2:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.d.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)

2ed2::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
12ed2::/282ed2:f:ffff:ffff:ffff:ffff:ffff:ffff
22ed2:10::/282ed2:1f:ffff:ffff:ffff:ffff:ffff:ffff
32ed2:20::/282ed2:2f:ffff:ffff:ffff:ffff:ffff:ffff
42ed2:30::/282ed2:3f:ffff:ffff:ffff:ffff:ffff:ffff
52ed2:40::/282ed2:4f:ffff:ffff:ffff:ffff:ffff:ffff
62ed2:50::/282ed2:5f:ffff:ffff:ffff:ffff:ffff:ffff
72ed2:60::/282ed2:6f:ffff:ffff:ffff:ffff:ffff:ffff
82ed2:70::/282ed2:7f:ffff:ffff:ffff:ffff:ffff:ffff
92ed2:80::/282ed2:8f:ffff:ffff:ffff:ffff:ffff:ffff
102ed2:90::/282ed2:9f:ffff:ffff:ffff:ffff:ffff:ffff
112ed2:a0::/282ed2:af:ffff:ffff:ffff:ffff:ffff:ffff
122ed2:b0::/282ed2:bf:ffff:ffff:ffff:ffff:ffff:ffff
132ed2:c0::/282ed2:cf:ffff:ffff:ffff:ffff:ffff:ffff
142ed2:d0::/282ed2:df:ffff:ffff:ffff:ffff:ffff:ffff
152ed2:e0::/282ed2:ef:ffff:ffff:ffff:ffff:ffff:ffff
162ed2:f0::/282ed2:ff:ffff:ffff:ffff:ffff:ffff:ffff
172ed2:100::/282ed2:10f:ffff:ffff:ffff:ffff:ffff:ffff
182ed2:110::/282ed2:11f:ffff:ffff:ffff:ffff:ffff:ffff
192ed2:120::/282ed2:12f:ffff:ffff:ffff:ffff:ffff:ffff
202ed2:130::/282ed2:13f:ffff:ffff:ffff:ffff:ffff:ffff
212ed2:140::/282ed2:14f:ffff:ffff:ffff:ffff:ffff:ffff
222ed2:150::/282ed2:15f:ffff:ffff:ffff:ffff:ffff:ffff
232ed2:160::/282ed2:16f:ffff:ffff:ffff:ffff:ffff:ffff
242ed2:170::/282ed2:17f:ffff:ffff:ffff:ffff:ffff:ffff
252ed2:180::/282ed2:18f:ffff:ffff:ffff:ffff:ffff:ffff
262ed2:190::/282ed2:19f:ffff:ffff:ffff:ffff:ffff:ffff
272ed2:1a0::/282ed2:1af:ffff:ffff:ffff:ffff:ffff:ffff
282ed2:1b0::/282ed2:1bf:ffff:ffff:ffff:ffff:ffff:ffff
292ed2:1c0::/282ed2:1cf:ffff:ffff:ffff:ffff:ffff:ffff
302ed2:1d0::/282ed2:1df:ffff:ffff:ffff:ffff:ffff:ffff
312ed2:1e0::/282ed2:1ef:ffff:ffff:ffff:ffff:ffff:ffff
322ed2:1f0::/282ed2:1ff:ffff:ffff:ffff:ffff:ffff:ffff
332ed2:200::/282ed2:20f:ffff:ffff:ffff:ffff:ffff:ffff
342ed2:210::/282ed2:21f:ffff:ffff:ffff:ffff:ffff:ffff
352ed2:220::/282ed2:22f:ffff:ffff:ffff:ffff:ffff:ffff
362ed2:230::/282ed2:23f:ffff:ffff:ffff:ffff:ffff:ffff
372ed2:240::/282ed2:24f:ffff:ffff:ffff:ffff:ffff:ffff
382ed2:250::/282ed2:25f:ffff:ffff:ffff:ffff:ffff:ffff
392ed2:260::/282ed2:26f:ffff:ffff:ffff:ffff:ffff:ffff
402ed2:270::/282ed2:27f:ffff:ffff:ffff:ffff:ffff:ffff
412ed2:280::/282ed2:28f:ffff:ffff:ffff:ffff:ffff:ffff
422ed2:290::/282ed2:29f:ffff:ffff:ffff:ffff:ffff:ffff
432ed2:2a0::/282ed2:2af:ffff:ffff:ffff:ffff:ffff:ffff
442ed2:2b0::/282ed2:2bf:ffff:ffff:ffff:ffff:ffff:ffff
452ed2:2c0::/282ed2:2cf:ffff:ffff:ffff:ffff:ffff:ffff
462ed2:2d0::/282ed2:2df:ffff:ffff:ffff:ffff:ffff:ffff
472ed2:2e0::/282ed2:2ef:ffff:ffff:ffff:ffff:ffff:ffff
482ed2:2f0::/282ed2:2ff:ffff:ffff:ffff:ffff:ffff:ffff
492ed2:300::/282ed2:30f:ffff:ffff:ffff:ffff:ffff:ffff
502ed2:310::/282ed2:31f:ffff:ffff:ffff:ffff:ffff:ffff
512ed2:320::/282ed2:32f:ffff:ffff:ffff:ffff:ffff:ffff
522ed2:330::/282ed2:33f:ffff:ffff:ffff:ffff:ffff:ffff
532ed2:340::/282ed2:34f:ffff:ffff:ffff:ffff:ffff:ffff
542ed2:350::/282ed2:35f:ffff:ffff:ffff:ffff:ffff:ffff
552ed2:360::/282ed2:36f:ffff:ffff:ffff:ffff:ffff:ffff
562ed2:370::/282ed2:37f:ffff:ffff:ffff:ffff:ffff:ffff
572ed2:380::/282ed2:38f:ffff:ffff:ffff:ffff:ffff:ffff
582ed2:390::/282ed2:39f:ffff:ffff:ffff:ffff:ffff:ffff
592ed2:3a0::/282ed2:3af:ffff:ffff:ffff:ffff:ffff:ffff
602ed2:3b0::/282ed2:3bf:ffff:ffff:ffff:ffff:ffff:ffff
612ed2:3c0::/282ed2:3cf:ffff:ffff:ffff:ffff:ffff:ffff
622ed2:3d0::/282ed2:3df:ffff:ffff:ffff:ffff:ffff:ffff
632ed2:3e0::/282ed2:3ef:ffff:ffff:ffff:ffff:ffff:ffff
642ed2:3f0::/282ed2:3ff:ffff:ffff:ffff:ffff:ffff:ffff
652ed2:400::/282ed2:40f:ffff:ffff:ffff:ffff:ffff:ffff
662ed2:410::/282ed2:41f:ffff:ffff:ffff:ffff:ffff:ffff
672ed2:420::/282ed2:42f:ffff:ffff:ffff:ffff:ffff:ffff
682ed2:430::/282ed2:43f:ffff:ffff:ffff:ffff:ffff:ffff
692ed2:440::/282ed2:44f:ffff:ffff:ffff:ffff:ffff:ffff
702ed2:450::/282ed2:45f:ffff:ffff:ffff:ffff:ffff:ffff
712ed2:460::/282ed2:46f:ffff:ffff:ffff:ffff:ffff:ffff
722ed2:470::/282ed2:47f:ffff:ffff:ffff:ffff:ffff:ffff
732ed2:480::/282ed2:48f:ffff:ffff:ffff:ffff:ffff:ffff
742ed2:490::/282ed2:49f:ffff:ffff:ffff:ffff:ffff:ffff
752ed2:4a0::/282ed2:4af:ffff:ffff:ffff:ffff:ffff:ffff
762ed2:4b0::/282ed2:4bf:ffff:ffff:ffff:ffff:ffff:ffff
772ed2:4c0::/282ed2:4cf:ffff:ffff:ffff:ffff:ffff:ffff
782ed2:4d0::/282ed2:4df:ffff:ffff:ffff:ffff:ffff:ffff
792ed2:4e0::/282ed2:4ef:ffff:ffff:ffff:ffff:ffff:ffff
802ed2:4f0::/282ed2:4ff:ffff:ffff:ffff:ffff:ffff:ffff
812ed2:500::/282ed2:50f:ffff:ffff:ffff:ffff:ffff:ffff
822ed2:510::/282ed2:51f:ffff:ffff:ffff:ffff:ffff:ffff
832ed2:520::/282ed2:52f:ffff:ffff:ffff:ffff:ffff:ffff
842ed2:530::/282ed2:53f:ffff:ffff:ffff:ffff:ffff:ffff
852ed2:540::/282ed2:54f:ffff:ffff:ffff:ffff:ffff:ffff
862ed2:550::/282ed2:55f:ffff:ffff:ffff:ffff:ffff:ffff
872ed2:560::/282ed2:56f:ffff:ffff:ffff:ffff:ffff:ffff
882ed2:570::/282ed2:57f:ffff:ffff:ffff:ffff:ffff:ffff
892ed2:580::/282ed2:58f:ffff:ffff:ffff:ffff:ffff:ffff
902ed2:590::/282ed2:59f:ffff:ffff:ffff:ffff:ffff:ffff
912ed2:5a0::/282ed2:5af:ffff:ffff:ffff:ffff:ffff:ffff
922ed2:5b0::/282ed2:5bf:ffff:ffff:ffff:ffff:ffff:ffff
932ed2:5c0::/282ed2:5cf:ffff:ffff:ffff:ffff:ffff:ffff
942ed2:5d0::/282ed2:5df:ffff:ffff:ffff:ffff:ffff:ffff
952ed2:5e0::/282ed2:5ef:ffff:ffff:ffff:ffff:ffff:ffff
962ed2:5f0::/282ed2:5ff:ffff:ffff:ffff:ffff:ffff:ffff
972ed2:600::/282ed2:60f:ffff:ffff:ffff:ffff:ffff:ffff
982ed2:610::/282ed2:61f:ffff:ffff:ffff:ffff:ffff:ffff
992ed2:620::/282ed2:62f:ffff:ffff:ffff:ffff:ffff:ffff
1002ed2:630::/282ed2:63f:ffff:ffff:ffff:ffff:ffff:ffff
1012ed2:640::/282ed2:64f:ffff:ffff:ffff:ffff:ffff:ffff
1022ed2:650::/282ed2:65f:ffff:ffff:ffff:ffff:ffff:ffff
1032ed2:660::/282ed2:66f:ffff:ffff:ffff:ffff:ffff:ffff
1042ed2:670::/282ed2:67f:ffff:ffff:ffff:ffff:ffff:ffff
1052ed2:680::/282ed2:68f:ffff:ffff:ffff:ffff:ffff:ffff
1062ed2:690::/282ed2:69f:ffff:ffff:ffff:ffff:ffff:ffff
1072ed2:6a0::/282ed2:6af:ffff:ffff:ffff:ffff:ffff:ffff
1082ed2:6b0::/282ed2:6bf:ffff:ffff:ffff:ffff:ffff:ffff
1092ed2:6c0::/282ed2:6cf:ffff:ffff:ffff:ffff:ffff:ffff
1102ed2:6d0::/282ed2:6df:ffff:ffff:ffff:ffff:ffff:ffff
1112ed2:6e0::/282ed2:6ef:ffff:ffff:ffff:ffff:ffff:ffff
1122ed2:6f0::/282ed2:6ff:ffff:ffff:ffff:ffff:ffff:ffff
1132ed2:700::/282ed2:70f:ffff:ffff:ffff:ffff:ffff:ffff
1142ed2:710::/282ed2:71f:ffff:ffff:ffff:ffff:ffff:ffff
1152ed2:720::/282ed2:72f:ffff:ffff:ffff:ffff:ffff:ffff
1162ed2:730::/282ed2:73f:ffff:ffff:ffff:ffff:ffff:ffff
1172ed2:740::/282ed2:74f:ffff:ffff:ffff:ffff:ffff:ffff
1182ed2:750::/282ed2:75f:ffff:ffff:ffff:ffff:ffff:ffff
1192ed2:760::/282ed2:76f:ffff:ffff:ffff:ffff:ffff:ffff
1202ed2:770::/282ed2:77f:ffff:ffff:ffff:ffff:ffff:ffff
1212ed2:780::/282ed2:78f:ffff:ffff:ffff:ffff:ffff:ffff
1222ed2:790::/282ed2:79f:ffff:ffff:ffff:ffff:ffff:ffff
1232ed2:7a0::/282ed2:7af:ffff:ffff:ffff:ffff:ffff:ffff
1242ed2:7b0::/282ed2:7bf:ffff:ffff:ffff:ffff:ffff:ffff
1252ed2:7c0::/282ed2:7cf:ffff:ffff:ffff:ffff:ffff:ffff
1262ed2:7d0::/282ed2:7df:ffff:ffff:ffff:ffff:ffff:ffff
1272ed2:7e0::/282ed2:7ef:ffff:ffff:ffff:ffff:ffff:ffff
1282ed2:7f0::/282ed2:7ff:ffff:ffff:ffff:ffff:ffff:ffff
1292ed2:800::/282ed2:80f:ffff:ffff:ffff:ffff:ffff:ffff
1302ed2:810::/282ed2:81f:ffff:ffff:ffff:ffff:ffff:ffff
1312ed2:820::/282ed2:82f:ffff:ffff:ffff:ffff:ffff:ffff
1322ed2:830::/282ed2:83f:ffff:ffff:ffff:ffff:ffff:ffff
1332ed2:840::/282ed2:84f:ffff:ffff:ffff:ffff:ffff:ffff
1342ed2:850::/282ed2:85f:ffff:ffff:ffff:ffff:ffff:ffff
1352ed2:860::/282ed2:86f:ffff:ffff:ffff:ffff:ffff:ffff
1362ed2:870::/282ed2:87f:ffff:ffff:ffff:ffff:ffff:ffff
1372ed2:880::/282ed2:88f:ffff:ffff:ffff:ffff:ffff:ffff
1382ed2:890::/282ed2:89f:ffff:ffff:ffff:ffff:ffff:ffff
1392ed2:8a0::/282ed2:8af:ffff:ffff:ffff:ffff:ffff:ffff
1402ed2:8b0::/282ed2:8bf:ffff:ffff:ffff:ffff:ffff:ffff
1412ed2:8c0::/282ed2:8cf:ffff:ffff:ffff:ffff:ffff:ffff
1422ed2:8d0::/282ed2:8df:ffff:ffff:ffff:ffff:ffff:ffff
1432ed2:8e0::/282ed2:8ef:ffff:ffff:ffff:ffff:ffff:ffff
1442ed2:8f0::/282ed2:8ff:ffff:ffff:ffff:ffff:ffff:ffff
1452ed2:900::/282ed2:90f:ffff:ffff:ffff:ffff:ffff:ffff
1462ed2:910::/282ed2:91f:ffff:ffff:ffff:ffff:ffff:ffff
1472ed2:920::/282ed2:92f:ffff:ffff:ffff:ffff:ffff:ffff
1482ed2:930::/282ed2:93f:ffff:ffff:ffff:ffff:ffff:ffff
1492ed2:940::/282ed2:94f:ffff:ffff:ffff:ffff:ffff:ffff
1502ed2:950::/282ed2:95f:ffff:ffff:ffff:ffff:ffff:ffff
1512ed2:960::/282ed2:96f:ffff:ffff:ffff:ffff:ffff:ffff
1522ed2:970::/282ed2:97f:ffff:ffff:ffff:ffff:ffff:ffff
1532ed2:980::/282ed2:98f:ffff:ffff:ffff:ffff:ffff:ffff
1542ed2:990::/282ed2:99f:ffff:ffff:ffff:ffff:ffff:ffff
1552ed2:9a0::/282ed2:9af:ffff:ffff:ffff:ffff:ffff:ffff
1562ed2:9b0::/282ed2:9bf:ffff:ffff:ffff:ffff:ffff:ffff
1572ed2:9c0::/282ed2:9cf:ffff:ffff:ffff:ffff:ffff:ffff
1582ed2:9d0::/282ed2:9df:ffff:ffff:ffff:ffff:ffff:ffff
1592ed2:9e0::/282ed2:9ef:ffff:ffff:ffff:ffff:ffff:ffff
1602ed2:9f0::/282ed2:9ff:ffff:ffff:ffff:ffff:ffff:ffff
1612ed2:a00::/282ed2:a0f:ffff:ffff:ffff:ffff:ffff:ffff
1622ed2:a10::/282ed2:a1f:ffff:ffff:ffff:ffff:ffff:ffff
1632ed2:a20::/282ed2:a2f:ffff:ffff:ffff:ffff:ffff:ffff
1642ed2:a30::/282ed2:a3f:ffff:ffff:ffff:ffff:ffff:ffff
1652ed2:a40::/282ed2:a4f:ffff:ffff:ffff:ffff:ffff:ffff
1662ed2:a50::/282ed2:a5f:ffff:ffff:ffff:ffff:ffff:ffff
1672ed2:a60::/282ed2:a6f:ffff:ffff:ffff:ffff:ffff:ffff
1682ed2:a70::/282ed2:a7f:ffff:ffff:ffff:ffff:ffff:ffff
1692ed2:a80::/282ed2:a8f:ffff:ffff:ffff:ffff:ffff:ffff
1702ed2:a90::/282ed2:a9f:ffff:ffff:ffff:ffff:ffff:ffff
1712ed2:aa0::/282ed2:aaf:ffff:ffff:ffff:ffff:ffff:ffff
1722ed2:ab0::/282ed2:abf:ffff:ffff:ffff:ffff:ffff:ffff
1732ed2:ac0::/282ed2:acf:ffff:ffff:ffff:ffff:ffff:ffff
1742ed2:ad0::/282ed2:adf:ffff:ffff:ffff:ffff:ffff:ffff
1752ed2:ae0::/282ed2:aef:ffff:ffff:ffff:ffff:ffff:ffff
1762ed2:af0::/282ed2:aff:ffff:ffff:ffff:ffff:ffff:ffff
1772ed2:b00::/282ed2:b0f:ffff:ffff:ffff:ffff:ffff:ffff
1782ed2:b10::/282ed2:b1f:ffff:ffff:ffff:ffff:ffff:ffff
1792ed2:b20::/282ed2:b2f:ffff:ffff:ffff:ffff:ffff:ffff
1802ed2:b30::/282ed2:b3f:ffff:ffff:ffff:ffff:ffff:ffff
1812ed2:b40::/282ed2:b4f:ffff:ffff:ffff:ffff:ffff:ffff
1822ed2:b50::/282ed2:b5f:ffff:ffff:ffff:ffff:ffff:ffff
1832ed2:b60::/282ed2:b6f:ffff:ffff:ffff:ffff:ffff:ffff
1842ed2:b70::/282ed2:b7f:ffff:ffff:ffff:ffff:ffff:ffff
1852ed2:b80::/282ed2:b8f:ffff:ffff:ffff:ffff:ffff:ffff
1862ed2:b90::/282ed2:b9f:ffff:ffff:ffff:ffff:ffff:ffff
1872ed2:ba0::/282ed2:baf:ffff:ffff:ffff:ffff:ffff:ffff
1882ed2:bb0::/282ed2:bbf:ffff:ffff:ffff:ffff:ffff:ffff
1892ed2:bc0::/282ed2:bcf:ffff:ffff:ffff:ffff:ffff:ffff
1902ed2:bd0::/282ed2:bdf:ffff:ffff:ffff:ffff:ffff:ffff
1912ed2:be0::/282ed2:bef:ffff:ffff:ffff:ffff:ffff:ffff
1922ed2:bf0::/282ed2:bff:ffff:ffff:ffff:ffff:ffff:ffff
1932ed2:c00::/282ed2:c0f:ffff:ffff:ffff:ffff:ffff:ffff
1942ed2:c10::/282ed2:c1f:ffff:ffff:ffff:ffff:ffff:ffff
1952ed2:c20::/282ed2:c2f:ffff:ffff:ffff:ffff:ffff:ffff
1962ed2:c30::/282ed2:c3f:ffff:ffff:ffff:ffff:ffff:ffff
1972ed2:c40::/282ed2:c4f:ffff:ffff:ffff:ffff:ffff:ffff
1982ed2:c50::/282ed2:c5f:ffff:ffff:ffff:ffff:ffff:ffff
1992ed2:c60::/282ed2:c6f:ffff:ffff:ffff:ffff:ffff:ffff
2002ed2:c70::/282ed2:c7f:ffff:ffff:ffff:ffff:ffff:ffff
2012ed2:c80::/282ed2:c8f:ffff:ffff:ffff:ffff:ffff:ffff
2022ed2:c90::/282ed2:c9f:ffff:ffff:ffff:ffff:ffff:ffff
2032ed2:ca0::/282ed2:caf:ffff:ffff:ffff:ffff:ffff:ffff
2042ed2:cb0::/282ed2:cbf:ffff:ffff:ffff:ffff:ffff:ffff
2052ed2:cc0::/282ed2:ccf:ffff:ffff:ffff:ffff:ffff:ffff
2062ed2:cd0::/282ed2:cdf:ffff:ffff:ffff:ffff:ffff:ffff
2072ed2:ce0::/282ed2:cef:ffff:ffff:ffff:ffff:ffff:ffff
2082ed2:cf0::/282ed2:cff:ffff:ffff:ffff:ffff:ffff:ffff
2092ed2:d00::/282ed2:d0f:ffff:ffff:ffff:ffff:ffff:ffff
2102ed2:d10::/282ed2:d1f:ffff:ffff:ffff:ffff:ffff:ffff
2112ed2:d20::/282ed2:d2f:ffff:ffff:ffff:ffff:ffff:ffff
2122ed2:d30::/282ed2:d3f:ffff:ffff:ffff:ffff:ffff:ffff
2132ed2:d40::/282ed2:d4f:ffff:ffff:ffff:ffff:ffff:ffff
2142ed2:d50::/282ed2:d5f:ffff:ffff:ffff:ffff:ffff:ffff
2152ed2:d60::/282ed2:d6f:ffff:ffff:ffff:ffff:ffff:ffff
2162ed2:d70::/282ed2:d7f:ffff:ffff:ffff:ffff:ffff:ffff
2172ed2:d80::/282ed2:d8f:ffff:ffff:ffff:ffff:ffff:ffff
2182ed2:d90::/282ed2:d9f:ffff:ffff:ffff:ffff:ffff:ffff
2192ed2:da0::/282ed2:daf:ffff:ffff:ffff:ffff:ffff:ffff
2202ed2:db0::/282ed2:dbf:ffff:ffff:ffff:ffff:ffff:ffff
2212ed2:dc0::/282ed2:dcf:ffff:ffff:ffff:ffff:ffff:ffff
2222ed2:dd0::/282ed2:ddf:ffff:ffff:ffff:ffff:ffff:ffff
2232ed2:de0::/282ed2:def:ffff:ffff:ffff:ffff:ffff:ffff
2242ed2:df0::/282ed2:dff:ffff:ffff:ffff:ffff:ffff:ffff
2252ed2:e00::/282ed2:e0f:ffff:ffff:ffff:ffff:ffff:ffff
2262ed2:e10::/282ed2:e1f:ffff:ffff:ffff:ffff:ffff:ffff
2272ed2:e20::/282ed2:e2f:ffff:ffff:ffff:ffff:ffff:ffff
2282ed2:e30::/282ed2:e3f:ffff:ffff:ffff:ffff:ffff:ffff
2292ed2:e40::/282ed2:e4f:ffff:ffff:ffff:ffff:ffff:ffff
2302ed2:e50::/282ed2:e5f:ffff:ffff:ffff:ffff:ffff:ffff
2312ed2:e60::/282ed2:e6f:ffff:ffff:ffff:ffff:ffff:ffff
2322ed2:e70::/282ed2:e7f:ffff:ffff:ffff:ffff:ffff:ffff
2332ed2:e80::/282ed2:e8f:ffff:ffff:ffff:ffff:ffff:ffff
2342ed2:e90::/282ed2:e9f:ffff:ffff:ffff:ffff:ffff:ffff
2352ed2:ea0::/282ed2:eaf:ffff:ffff:ffff:ffff:ffff:ffff
2362ed2:eb0::/282ed2:ebf:ffff:ffff:ffff:ffff:ffff:ffff
2372ed2:ec0::/282ed2:ecf:ffff:ffff:ffff:ffff:ffff:ffff
2382ed2:ed0::/282ed2:edf:ffff:ffff:ffff:ffff:ffff:ffff
2392ed2:ee0::/282ed2:eef:ffff:ffff:ffff:ffff:ffff:ffff
2402ed2:ef0::/282ed2:eff:ffff:ffff:ffff:ffff:ffff:ffff
2412ed2:f00::/282ed2:f0f:ffff:ffff:ffff:ffff:ffff:ffff
2422ed2:f10::/282ed2:f1f:ffff:ffff:ffff:ffff:ffff:ffff
2432ed2:f20::/282ed2:f2f:ffff:ffff:ffff:ffff:ffff:ffff
2442ed2:f30::/282ed2:f3f:ffff:ffff:ffff:ffff:ffff:ffff
2452ed2:f40::/282ed2:f4f:ffff:ffff:ffff:ffff:ffff:ffff
2462ed2:f50::/282ed2:f5f:ffff:ffff:ffff:ffff:ffff:ffff
2472ed2:f60::/282ed2:f6f:ffff:ffff:ffff:ffff:ffff:ffff
2482ed2:f70::/282ed2:f7f:ffff:ffff:ffff:ffff:ffff:ffff
2492ed2:f80::/282ed2:f8f:ffff:ffff:ffff:ffff:ffff:ffff
2502ed2:f90::/282ed2:f9f:ffff:ffff:ffff:ffff:ffff:ffff
2512ed2:fa0::/282ed2:faf:ffff:ffff:ffff:ffff:ffff:ffff
2522ed2:fb0::/282ed2:fbf:ffff:ffff:ffff:ffff:ffff:ffff
2532ed2:fc0::/282ed2:fcf:ffff:ffff:ffff:ffff:ffff:ffff
2542ed2:fd0::/282ed2:fdf:ffff:ffff:ffff:ffff:ffff:ffff
2552ed2:fe0::/282ed2:fef:ffff:ffff:ffff:ffff:ffff:ffff
2562ed2:ff0::/282ed2: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.