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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
2330::/12
First address
2330::
Last address
233f: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
2330:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.3.2.ip6.arpa
Split into smaller subnets/28
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2330::/12 makes 65,536 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
12330::/282330:f:ffff:ffff:ffff:ffff:ffff:ffff
22330:10::/282330:1f:ffff:ffff:ffff:ffff:ffff:ffff
32330:20::/282330:2f:ffff:ffff:ffff:ffff:ffff:ffff
42330:30::/282330:3f:ffff:ffff:ffff:ffff:ffff:ffff
52330:40::/282330:4f:ffff:ffff:ffff:ffff:ffff:ffff
62330:50::/282330:5f:ffff:ffff:ffff:ffff:ffff:ffff
72330:60::/282330:6f:ffff:ffff:ffff:ffff:ffff:ffff
82330:70::/282330:7f:ffff:ffff:ffff:ffff:ffff:ffff
92330:80::/282330:8f:ffff:ffff:ffff:ffff:ffff:ffff
102330:90::/282330:9f:ffff:ffff:ffff:ffff:ffff:ffff
112330:a0::/282330:af:ffff:ffff:ffff:ffff:ffff:ffff
122330:b0::/282330:bf:ffff:ffff:ffff:ffff:ffff:ffff
132330:c0::/282330:cf:ffff:ffff:ffff:ffff:ffff:ffff
142330:d0::/282330:df:ffff:ffff:ffff:ffff:ffff:ffff
152330:e0::/282330:ef:ffff:ffff:ffff:ffff:ffff:ffff
162330:f0::/282330:ff:ffff:ffff:ffff:ffff:ffff:ffff
172330:100::/282330:10f:ffff:ffff:ffff:ffff:ffff:ffff
182330:110::/282330:11f:ffff:ffff:ffff:ffff:ffff:ffff
192330:120::/282330:12f:ffff:ffff:ffff:ffff:ffff:ffff
202330:130::/282330:13f:ffff:ffff:ffff:ffff:ffff:ffff
212330:140::/282330:14f:ffff:ffff:ffff:ffff:ffff:ffff
222330:150::/282330:15f:ffff:ffff:ffff:ffff:ffff:ffff
232330:160::/282330:16f:ffff:ffff:ffff:ffff:ffff:ffff
242330:170::/282330:17f:ffff:ffff:ffff:ffff:ffff:ffff
252330:180::/282330:18f:ffff:ffff:ffff:ffff:ffff:ffff
262330:190::/282330:19f:ffff:ffff:ffff:ffff:ffff:ffff
272330:1a0::/282330:1af:ffff:ffff:ffff:ffff:ffff:ffff
282330:1b0::/282330:1bf:ffff:ffff:ffff:ffff:ffff:ffff
292330:1c0::/282330:1cf:ffff:ffff:ffff:ffff:ffff:ffff
302330:1d0::/282330:1df:ffff:ffff:ffff:ffff:ffff:ffff
312330:1e0::/282330:1ef:ffff:ffff:ffff:ffff:ffff:ffff
322330:1f0::/282330:1ff:ffff:ffff:ffff:ffff:ffff:ffff
332330:200::/282330:20f:ffff:ffff:ffff:ffff:ffff:ffff
342330:210::/282330:21f:ffff:ffff:ffff:ffff:ffff:ffff
352330:220::/282330:22f:ffff:ffff:ffff:ffff:ffff:ffff
362330:230::/282330:23f:ffff:ffff:ffff:ffff:ffff:ffff
372330:240::/282330:24f:ffff:ffff:ffff:ffff:ffff:ffff
382330:250::/282330:25f:ffff:ffff:ffff:ffff:ffff:ffff
392330:260::/282330:26f:ffff:ffff:ffff:ffff:ffff:ffff
402330:270::/282330:27f:ffff:ffff:ffff:ffff:ffff:ffff
412330:280::/282330:28f:ffff:ffff:ffff:ffff:ffff:ffff
422330:290::/282330:29f:ffff:ffff:ffff:ffff:ffff:ffff
432330:2a0::/282330:2af:ffff:ffff:ffff:ffff:ffff:ffff
442330:2b0::/282330:2bf:ffff:ffff:ffff:ffff:ffff:ffff
452330:2c0::/282330:2cf:ffff:ffff:ffff:ffff:ffff:ffff
462330:2d0::/282330:2df:ffff:ffff:ffff:ffff:ffff:ffff
472330:2e0::/282330:2ef:ffff:ffff:ffff:ffff:ffff:ffff
482330:2f0::/282330:2ff:ffff:ffff:ffff:ffff:ffff:ffff
492330:300::/282330:30f:ffff:ffff:ffff:ffff:ffff:ffff
502330:310::/282330:31f:ffff:ffff:ffff:ffff:ffff:ffff
512330:320::/282330:32f:ffff:ffff:ffff:ffff:ffff:ffff
522330:330::/282330:33f:ffff:ffff:ffff:ffff:ffff:ffff
532330:340::/282330:34f:ffff:ffff:ffff:ffff:ffff:ffff
542330:350::/282330:35f:ffff:ffff:ffff:ffff:ffff:ffff
552330:360::/282330:36f:ffff:ffff:ffff:ffff:ffff:ffff
562330:370::/282330:37f:ffff:ffff:ffff:ffff:ffff:ffff
572330:380::/282330:38f:ffff:ffff:ffff:ffff:ffff:ffff
582330:390::/282330:39f:ffff:ffff:ffff:ffff:ffff:ffff
592330:3a0::/282330:3af:ffff:ffff:ffff:ffff:ffff:ffff
602330:3b0::/282330:3bf:ffff:ffff:ffff:ffff:ffff:ffff
612330:3c0::/282330:3cf:ffff:ffff:ffff:ffff:ffff:ffff
622330:3d0::/282330:3df:ffff:ffff:ffff:ffff:ffff:ffff
632330:3e0::/282330:3ef:ffff:ffff:ffff:ffff:ffff:ffff
642330:3f0::/282330:3ff:ffff:ffff:ffff:ffff:ffff:ffff
652330:400::/282330:40f:ffff:ffff:ffff:ffff:ffff:ffff
662330:410::/282330:41f:ffff:ffff:ffff:ffff:ffff:ffff
672330:420::/282330:42f:ffff:ffff:ffff:ffff:ffff:ffff
682330:430::/282330:43f:ffff:ffff:ffff:ffff:ffff:ffff
692330:440::/282330:44f:ffff:ffff:ffff:ffff:ffff:ffff
702330:450::/282330:45f:ffff:ffff:ffff:ffff:ffff:ffff
712330:460::/282330:46f:ffff:ffff:ffff:ffff:ffff:ffff
722330:470::/282330:47f:ffff:ffff:ffff:ffff:ffff:ffff
732330:480::/282330:48f:ffff:ffff:ffff:ffff:ffff:ffff
742330:490::/282330:49f:ffff:ffff:ffff:ffff:ffff:ffff
752330:4a0::/282330:4af:ffff:ffff:ffff:ffff:ffff:ffff
762330:4b0::/282330:4bf:ffff:ffff:ffff:ffff:ffff:ffff
772330:4c0::/282330:4cf:ffff:ffff:ffff:ffff:ffff:ffff
782330:4d0::/282330:4df:ffff:ffff:ffff:ffff:ffff:ffff
792330:4e0::/282330:4ef:ffff:ffff:ffff:ffff:ffff:ffff
802330:4f0::/282330:4ff:ffff:ffff:ffff:ffff:ffff:ffff
812330:500::/282330:50f:ffff:ffff:ffff:ffff:ffff:ffff
822330:510::/282330:51f:ffff:ffff:ffff:ffff:ffff:ffff
832330:520::/282330:52f:ffff:ffff:ffff:ffff:ffff:ffff
842330:530::/282330:53f:ffff:ffff:ffff:ffff:ffff:ffff
852330:540::/282330:54f:ffff:ffff:ffff:ffff:ffff:ffff
862330:550::/282330:55f:ffff:ffff:ffff:ffff:ffff:ffff
872330:560::/282330:56f:ffff:ffff:ffff:ffff:ffff:ffff
882330:570::/282330:57f:ffff:ffff:ffff:ffff:ffff:ffff
892330:580::/282330:58f:ffff:ffff:ffff:ffff:ffff:ffff
902330:590::/282330:59f:ffff:ffff:ffff:ffff:ffff:ffff
912330:5a0::/282330:5af:ffff:ffff:ffff:ffff:ffff:ffff
922330:5b0::/282330:5bf:ffff:ffff:ffff:ffff:ffff:ffff
932330:5c0::/282330:5cf:ffff:ffff:ffff:ffff:ffff:ffff
942330:5d0::/282330:5df:ffff:ffff:ffff:ffff:ffff:ffff
952330:5e0::/282330:5ef:ffff:ffff:ffff:ffff:ffff:ffff
962330:5f0::/282330:5ff:ffff:ffff:ffff:ffff:ffff:ffff
972330:600::/282330:60f:ffff:ffff:ffff:ffff:ffff:ffff
982330:610::/282330:61f:ffff:ffff:ffff:ffff:ffff:ffff
992330:620::/282330:62f:ffff:ffff:ffff:ffff:ffff:ffff
1002330:630::/282330:63f:ffff:ffff:ffff:ffff:ffff:ffff
1012330:640::/282330:64f:ffff:ffff:ffff:ffff:ffff:ffff
1022330:650::/282330:65f:ffff:ffff:ffff:ffff:ffff:ffff
1032330:660::/282330:66f:ffff:ffff:ffff:ffff:ffff:ffff
1042330:670::/282330:67f:ffff:ffff:ffff:ffff:ffff:ffff
1052330:680::/282330:68f:ffff:ffff:ffff:ffff:ffff:ffff
1062330:690::/282330:69f:ffff:ffff:ffff:ffff:ffff:ffff
1072330:6a0::/282330:6af:ffff:ffff:ffff:ffff:ffff:ffff
1082330:6b0::/282330:6bf:ffff:ffff:ffff:ffff:ffff:ffff
1092330:6c0::/282330:6cf:ffff:ffff:ffff:ffff:ffff:ffff
1102330:6d0::/282330:6df:ffff:ffff:ffff:ffff:ffff:ffff
1112330:6e0::/282330:6ef:ffff:ffff:ffff:ffff:ffff:ffff
1122330:6f0::/282330:6ff:ffff:ffff:ffff:ffff:ffff:ffff
1132330:700::/282330:70f:ffff:ffff:ffff:ffff:ffff:ffff
1142330:710::/282330:71f:ffff:ffff:ffff:ffff:ffff:ffff
1152330:720::/282330:72f:ffff:ffff:ffff:ffff:ffff:ffff
1162330:730::/282330:73f:ffff:ffff:ffff:ffff:ffff:ffff
1172330:740::/282330:74f:ffff:ffff:ffff:ffff:ffff:ffff
1182330:750::/282330:75f:ffff:ffff:ffff:ffff:ffff:ffff
1192330:760::/282330:76f:ffff:ffff:ffff:ffff:ffff:ffff
1202330:770::/282330:77f:ffff:ffff:ffff:ffff:ffff:ffff
1212330:780::/282330:78f:ffff:ffff:ffff:ffff:ffff:ffff
1222330:790::/282330:79f:ffff:ffff:ffff:ffff:ffff:ffff
1232330:7a0::/282330:7af:ffff:ffff:ffff:ffff:ffff:ffff
1242330:7b0::/282330:7bf:ffff:ffff:ffff:ffff:ffff:ffff
1252330:7c0::/282330:7cf:ffff:ffff:ffff:ffff:ffff:ffff
1262330:7d0::/282330:7df:ffff:ffff:ffff:ffff:ffff:ffff
1272330:7e0::/282330:7ef:ffff:ffff:ffff:ffff:ffff:ffff
1282330:7f0::/282330:7ff:ffff:ffff:ffff:ffff:ffff:ffff
1292330:800::/282330:80f:ffff:ffff:ffff:ffff:ffff:ffff
1302330:810::/282330:81f:ffff:ffff:ffff:ffff:ffff:ffff
1312330:820::/282330:82f:ffff:ffff:ffff:ffff:ffff:ffff
1322330:830::/282330:83f:ffff:ffff:ffff:ffff:ffff:ffff
1332330:840::/282330:84f:ffff:ffff:ffff:ffff:ffff:ffff
1342330:850::/282330:85f:ffff:ffff:ffff:ffff:ffff:ffff
1352330:860::/282330:86f:ffff:ffff:ffff:ffff:ffff:ffff
1362330:870::/282330:87f:ffff:ffff:ffff:ffff:ffff:ffff
1372330:880::/282330:88f:ffff:ffff:ffff:ffff:ffff:ffff
1382330:890::/282330:89f:ffff:ffff:ffff:ffff:ffff:ffff
1392330:8a0::/282330:8af:ffff:ffff:ffff:ffff:ffff:ffff
1402330:8b0::/282330:8bf:ffff:ffff:ffff:ffff:ffff:ffff
1412330:8c0::/282330:8cf:ffff:ffff:ffff:ffff:ffff:ffff
1422330:8d0::/282330:8df:ffff:ffff:ffff:ffff:ffff:ffff
1432330:8e0::/282330:8ef:ffff:ffff:ffff:ffff:ffff:ffff
1442330:8f0::/282330:8ff:ffff:ffff:ffff:ffff:ffff:ffff
1452330:900::/282330:90f:ffff:ffff:ffff:ffff:ffff:ffff
1462330:910::/282330:91f:ffff:ffff:ffff:ffff:ffff:ffff
1472330:920::/282330:92f:ffff:ffff:ffff:ffff:ffff:ffff
1482330:930::/282330:93f:ffff:ffff:ffff:ffff:ffff:ffff
1492330:940::/282330:94f:ffff:ffff:ffff:ffff:ffff:ffff
1502330:950::/282330:95f:ffff:ffff:ffff:ffff:ffff:ffff
1512330:960::/282330:96f:ffff:ffff:ffff:ffff:ffff:ffff
1522330:970::/282330:97f:ffff:ffff:ffff:ffff:ffff:ffff
1532330:980::/282330:98f:ffff:ffff:ffff:ffff:ffff:ffff
1542330:990::/282330:99f:ffff:ffff:ffff:ffff:ffff:ffff
1552330:9a0::/282330:9af:ffff:ffff:ffff:ffff:ffff:ffff
1562330:9b0::/282330:9bf:ffff:ffff:ffff:ffff:ffff:ffff
1572330:9c0::/282330:9cf:ffff:ffff:ffff:ffff:ffff:ffff
1582330:9d0::/282330:9df:ffff:ffff:ffff:ffff:ffff:ffff
1592330:9e0::/282330:9ef:ffff:ffff:ffff:ffff:ffff:ffff
1602330:9f0::/282330:9ff:ffff:ffff:ffff:ffff:ffff:ffff
1612330:a00::/282330:a0f:ffff:ffff:ffff:ffff:ffff:ffff
1622330:a10::/282330:a1f:ffff:ffff:ffff:ffff:ffff:ffff
1632330:a20::/282330:a2f:ffff:ffff:ffff:ffff:ffff:ffff
1642330:a30::/282330:a3f:ffff:ffff:ffff:ffff:ffff:ffff
1652330:a40::/282330:a4f:ffff:ffff:ffff:ffff:ffff:ffff
1662330:a50::/282330:a5f:ffff:ffff:ffff:ffff:ffff:ffff
1672330:a60::/282330:a6f:ffff:ffff:ffff:ffff:ffff:ffff
1682330:a70::/282330:a7f:ffff:ffff:ffff:ffff:ffff:ffff
1692330:a80::/282330:a8f:ffff:ffff:ffff:ffff:ffff:ffff
1702330:a90::/282330:a9f:ffff:ffff:ffff:ffff:ffff:ffff
1712330:aa0::/282330:aaf:ffff:ffff:ffff:ffff:ffff:ffff
1722330:ab0::/282330:abf:ffff:ffff:ffff:ffff:ffff:ffff
1732330:ac0::/282330:acf:ffff:ffff:ffff:ffff:ffff:ffff
1742330:ad0::/282330:adf:ffff:ffff:ffff:ffff:ffff:ffff
1752330:ae0::/282330:aef:ffff:ffff:ffff:ffff:ffff:ffff
1762330:af0::/282330:aff:ffff:ffff:ffff:ffff:ffff:ffff
1772330:b00::/282330:b0f:ffff:ffff:ffff:ffff:ffff:ffff
1782330:b10::/282330:b1f:ffff:ffff:ffff:ffff:ffff:ffff
1792330:b20::/282330:b2f:ffff:ffff:ffff:ffff:ffff:ffff
1802330:b30::/282330:b3f:ffff:ffff:ffff:ffff:ffff:ffff
1812330:b40::/282330:b4f:ffff:ffff:ffff:ffff:ffff:ffff
1822330:b50::/282330:b5f:ffff:ffff:ffff:ffff:ffff:ffff
1832330:b60::/282330:b6f:ffff:ffff:ffff:ffff:ffff:ffff
1842330:b70::/282330:b7f:ffff:ffff:ffff:ffff:ffff:ffff
1852330:b80::/282330:b8f:ffff:ffff:ffff:ffff:ffff:ffff
1862330:b90::/282330:b9f:ffff:ffff:ffff:ffff:ffff:ffff
1872330:ba0::/282330:baf:ffff:ffff:ffff:ffff:ffff:ffff
1882330:bb0::/282330:bbf:ffff:ffff:ffff:ffff:ffff:ffff
1892330:bc0::/282330:bcf:ffff:ffff:ffff:ffff:ffff:ffff
1902330:bd0::/282330:bdf:ffff:ffff:ffff:ffff:ffff:ffff
1912330:be0::/282330:bef:ffff:ffff:ffff:ffff:ffff:ffff
1922330:bf0::/282330:bff:ffff:ffff:ffff:ffff:ffff:ffff
1932330:c00::/282330:c0f:ffff:ffff:ffff:ffff:ffff:ffff
1942330:c10::/282330:c1f:ffff:ffff:ffff:ffff:ffff:ffff
1952330:c20::/282330:c2f:ffff:ffff:ffff:ffff:ffff:ffff
1962330:c30::/282330:c3f:ffff:ffff:ffff:ffff:ffff:ffff
1972330:c40::/282330:c4f:ffff:ffff:ffff:ffff:ffff:ffff
1982330:c50::/282330:c5f:ffff:ffff:ffff:ffff:ffff:ffff
1992330:c60::/282330:c6f:ffff:ffff:ffff:ffff:ffff:ffff
2002330:c70::/282330:c7f:ffff:ffff:ffff:ffff:ffff:ffff
2012330:c80::/282330:c8f:ffff:ffff:ffff:ffff:ffff:ffff
2022330:c90::/282330:c9f:ffff:ffff:ffff:ffff:ffff:ffff
2032330:ca0::/282330:caf:ffff:ffff:ffff:ffff:ffff:ffff
2042330:cb0::/282330:cbf:ffff:ffff:ffff:ffff:ffff:ffff
2052330:cc0::/282330:ccf:ffff:ffff:ffff:ffff:ffff:ffff
2062330:cd0::/282330:cdf:ffff:ffff:ffff:ffff:ffff:ffff
2072330:ce0::/282330:cef:ffff:ffff:ffff:ffff:ffff:ffff
2082330:cf0::/282330:cff:ffff:ffff:ffff:ffff:ffff:ffff
2092330:d00::/282330:d0f:ffff:ffff:ffff:ffff:ffff:ffff
2102330:d10::/282330:d1f:ffff:ffff:ffff:ffff:ffff:ffff
2112330:d20::/282330:d2f:ffff:ffff:ffff:ffff:ffff:ffff
2122330:d30::/282330:d3f:ffff:ffff:ffff:ffff:ffff:ffff
2132330:d40::/282330:d4f:ffff:ffff:ffff:ffff:ffff:ffff
2142330:d50::/282330:d5f:ffff:ffff:ffff:ffff:ffff:ffff
2152330:d60::/282330:d6f:ffff:ffff:ffff:ffff:ffff:ffff
2162330:d70::/282330:d7f:ffff:ffff:ffff:ffff:ffff:ffff
2172330:d80::/282330:d8f:ffff:ffff:ffff:ffff:ffff:ffff
2182330:d90::/282330:d9f:ffff:ffff:ffff:ffff:ffff:ffff
2192330:da0::/282330:daf:ffff:ffff:ffff:ffff:ffff:ffff
2202330:db0::/282330:dbf:ffff:ffff:ffff:ffff:ffff:ffff
2212330:dc0::/282330:dcf:ffff:ffff:ffff:ffff:ffff:ffff
2222330:dd0::/282330:ddf:ffff:ffff:ffff:ffff:ffff:ffff
2232330:de0::/282330:def:ffff:ffff:ffff:ffff:ffff:ffff
2242330:df0::/282330:dff:ffff:ffff:ffff:ffff:ffff:ffff
2252330:e00::/282330:e0f:ffff:ffff:ffff:ffff:ffff:ffff
2262330:e10::/282330:e1f:ffff:ffff:ffff:ffff:ffff:ffff
2272330:e20::/282330:e2f:ffff:ffff:ffff:ffff:ffff:ffff
2282330:e30::/282330:e3f:ffff:ffff:ffff:ffff:ffff:ffff
2292330:e40::/282330:e4f:ffff:ffff:ffff:ffff:ffff:ffff
2302330:e50::/282330:e5f:ffff:ffff:ffff:ffff:ffff:ffff
2312330:e60::/282330:e6f:ffff:ffff:ffff:ffff:ffff:ffff
2322330:e70::/282330:e7f:ffff:ffff:ffff:ffff:ffff:ffff
2332330:e80::/282330:e8f:ffff:ffff:ffff:ffff:ffff:ffff
2342330:e90::/282330:e9f:ffff:ffff:ffff:ffff:ffff:ffff
2352330:ea0::/282330:eaf:ffff:ffff:ffff:ffff:ffff:ffff
2362330:eb0::/282330:ebf:ffff:ffff:ffff:ffff:ffff:ffff
2372330:ec0::/282330:ecf:ffff:ffff:ffff:ffff:ffff:ffff
2382330:ed0::/282330:edf:ffff:ffff:ffff:ffff:ffff:ffff
2392330:ee0::/282330:eef:ffff:ffff:ffff:ffff:ffff:ffff
2402330:ef0::/282330:eff:ffff:ffff:ffff:ffff:ffff:ffff
2412330:f00::/282330:f0f:ffff:ffff:ffff:ffff:ffff:ffff
2422330:f10::/282330:f1f:ffff:ffff:ffff:ffff:ffff:ffff
2432330:f20::/282330:f2f:ffff:ffff:ffff:ffff:ffff:ffff
2442330:f30::/282330:f3f:ffff:ffff:ffff:ffff:ffff:ffff
2452330:f40::/282330:f4f:ffff:ffff:ffff:ffff:ffff:ffff
2462330:f50::/282330:f5f:ffff:ffff:ffff:ffff:ffff:ffff
2472330:f60::/282330:f6f:ffff:ffff:ffff:ffff:ffff:ffff
2482330:f70::/282330:f7f:ffff:ffff:ffff:ffff:ffff:ffff
2492330:f80::/282330:f8f:ffff:ffff:ffff:ffff:ffff:ffff
2502330:f90::/282330:f9f:ffff:ffff:ffff:ffff:ffff:ffff
2512330:fa0::/282330:faf:ffff:ffff:ffff:ffff:ffff:ffff
2522330:fb0::/282330:fbf:ffff:ffff:ffff:ffff:ffff:ffff
2532330:fc0::/282330:fcf:ffff:ffff:ffff:ffff:ffff:ffff
2542330:fd0::/282330:fdf:ffff:ffff:ffff:ffff:ffff:ffff
2552330:fe0::/282330:fef:ffff:ffff:ffff:ffff:ffff:ffff
2562330:ff0::/282330: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.