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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
2082::/16
First address
2082::
Last address
2082: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
2082:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.8.0.2.ip6.arpa
Split into smaller subnets/28
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

2082::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
12082::/282082:f:ffff:ffff:ffff:ffff:ffff:ffff
22082:10::/282082:1f:ffff:ffff:ffff:ffff:ffff:ffff
32082:20::/282082:2f:ffff:ffff:ffff:ffff:ffff:ffff
42082:30::/282082:3f:ffff:ffff:ffff:ffff:ffff:ffff
52082:40::/282082:4f:ffff:ffff:ffff:ffff:ffff:ffff
62082:50::/282082:5f:ffff:ffff:ffff:ffff:ffff:ffff
72082:60::/282082:6f:ffff:ffff:ffff:ffff:ffff:ffff
82082:70::/282082:7f:ffff:ffff:ffff:ffff:ffff:ffff
92082:80::/282082:8f:ffff:ffff:ffff:ffff:ffff:ffff
102082:90::/282082:9f:ffff:ffff:ffff:ffff:ffff:ffff
112082:a0::/282082:af:ffff:ffff:ffff:ffff:ffff:ffff
122082:b0::/282082:bf:ffff:ffff:ffff:ffff:ffff:ffff
132082:c0::/282082:cf:ffff:ffff:ffff:ffff:ffff:ffff
142082:d0::/282082:df:ffff:ffff:ffff:ffff:ffff:ffff
152082:e0::/282082:ef:ffff:ffff:ffff:ffff:ffff:ffff
162082:f0::/282082:ff:ffff:ffff:ffff:ffff:ffff:ffff
172082:100::/282082:10f:ffff:ffff:ffff:ffff:ffff:ffff
182082:110::/282082:11f:ffff:ffff:ffff:ffff:ffff:ffff
192082:120::/282082:12f:ffff:ffff:ffff:ffff:ffff:ffff
202082:130::/282082:13f:ffff:ffff:ffff:ffff:ffff:ffff
212082:140::/282082:14f:ffff:ffff:ffff:ffff:ffff:ffff
222082:150::/282082:15f:ffff:ffff:ffff:ffff:ffff:ffff
232082:160::/282082:16f:ffff:ffff:ffff:ffff:ffff:ffff
242082:170::/282082:17f:ffff:ffff:ffff:ffff:ffff:ffff
252082:180::/282082:18f:ffff:ffff:ffff:ffff:ffff:ffff
262082:190::/282082:19f:ffff:ffff:ffff:ffff:ffff:ffff
272082:1a0::/282082:1af:ffff:ffff:ffff:ffff:ffff:ffff
282082:1b0::/282082:1bf:ffff:ffff:ffff:ffff:ffff:ffff
292082:1c0::/282082:1cf:ffff:ffff:ffff:ffff:ffff:ffff
302082:1d0::/282082:1df:ffff:ffff:ffff:ffff:ffff:ffff
312082:1e0::/282082:1ef:ffff:ffff:ffff:ffff:ffff:ffff
322082:1f0::/282082:1ff:ffff:ffff:ffff:ffff:ffff:ffff
332082:200::/282082:20f:ffff:ffff:ffff:ffff:ffff:ffff
342082:210::/282082:21f:ffff:ffff:ffff:ffff:ffff:ffff
352082:220::/282082:22f:ffff:ffff:ffff:ffff:ffff:ffff
362082:230::/282082:23f:ffff:ffff:ffff:ffff:ffff:ffff
372082:240::/282082:24f:ffff:ffff:ffff:ffff:ffff:ffff
382082:250::/282082:25f:ffff:ffff:ffff:ffff:ffff:ffff
392082:260::/282082:26f:ffff:ffff:ffff:ffff:ffff:ffff
402082:270::/282082:27f:ffff:ffff:ffff:ffff:ffff:ffff
412082:280::/282082:28f:ffff:ffff:ffff:ffff:ffff:ffff
422082:290::/282082:29f:ffff:ffff:ffff:ffff:ffff:ffff
432082:2a0::/282082:2af:ffff:ffff:ffff:ffff:ffff:ffff
442082:2b0::/282082:2bf:ffff:ffff:ffff:ffff:ffff:ffff
452082:2c0::/282082:2cf:ffff:ffff:ffff:ffff:ffff:ffff
462082:2d0::/282082:2df:ffff:ffff:ffff:ffff:ffff:ffff
472082:2e0::/282082:2ef:ffff:ffff:ffff:ffff:ffff:ffff
482082:2f0::/282082:2ff:ffff:ffff:ffff:ffff:ffff:ffff
492082:300::/282082:30f:ffff:ffff:ffff:ffff:ffff:ffff
502082:310::/282082:31f:ffff:ffff:ffff:ffff:ffff:ffff
512082:320::/282082:32f:ffff:ffff:ffff:ffff:ffff:ffff
522082:330::/282082:33f:ffff:ffff:ffff:ffff:ffff:ffff
532082:340::/282082:34f:ffff:ffff:ffff:ffff:ffff:ffff
542082:350::/282082:35f:ffff:ffff:ffff:ffff:ffff:ffff
552082:360::/282082:36f:ffff:ffff:ffff:ffff:ffff:ffff
562082:370::/282082:37f:ffff:ffff:ffff:ffff:ffff:ffff
572082:380::/282082:38f:ffff:ffff:ffff:ffff:ffff:ffff
582082:390::/282082:39f:ffff:ffff:ffff:ffff:ffff:ffff
592082:3a0::/282082:3af:ffff:ffff:ffff:ffff:ffff:ffff
602082:3b0::/282082:3bf:ffff:ffff:ffff:ffff:ffff:ffff
612082:3c0::/282082:3cf:ffff:ffff:ffff:ffff:ffff:ffff
622082:3d0::/282082:3df:ffff:ffff:ffff:ffff:ffff:ffff
632082:3e0::/282082:3ef:ffff:ffff:ffff:ffff:ffff:ffff
642082:3f0::/282082:3ff:ffff:ffff:ffff:ffff:ffff:ffff
652082:400::/282082:40f:ffff:ffff:ffff:ffff:ffff:ffff
662082:410::/282082:41f:ffff:ffff:ffff:ffff:ffff:ffff
672082:420::/282082:42f:ffff:ffff:ffff:ffff:ffff:ffff
682082:430::/282082:43f:ffff:ffff:ffff:ffff:ffff:ffff
692082:440::/282082:44f:ffff:ffff:ffff:ffff:ffff:ffff
702082:450::/282082:45f:ffff:ffff:ffff:ffff:ffff:ffff
712082:460::/282082:46f:ffff:ffff:ffff:ffff:ffff:ffff
722082:470::/282082:47f:ffff:ffff:ffff:ffff:ffff:ffff
732082:480::/282082:48f:ffff:ffff:ffff:ffff:ffff:ffff
742082:490::/282082:49f:ffff:ffff:ffff:ffff:ffff:ffff
752082:4a0::/282082:4af:ffff:ffff:ffff:ffff:ffff:ffff
762082:4b0::/282082:4bf:ffff:ffff:ffff:ffff:ffff:ffff
772082:4c0::/282082:4cf:ffff:ffff:ffff:ffff:ffff:ffff
782082:4d0::/282082:4df:ffff:ffff:ffff:ffff:ffff:ffff
792082:4e0::/282082:4ef:ffff:ffff:ffff:ffff:ffff:ffff
802082:4f0::/282082:4ff:ffff:ffff:ffff:ffff:ffff:ffff
812082:500::/282082:50f:ffff:ffff:ffff:ffff:ffff:ffff
822082:510::/282082:51f:ffff:ffff:ffff:ffff:ffff:ffff
832082:520::/282082:52f:ffff:ffff:ffff:ffff:ffff:ffff
842082:530::/282082:53f:ffff:ffff:ffff:ffff:ffff:ffff
852082:540::/282082:54f:ffff:ffff:ffff:ffff:ffff:ffff
862082:550::/282082:55f:ffff:ffff:ffff:ffff:ffff:ffff
872082:560::/282082:56f:ffff:ffff:ffff:ffff:ffff:ffff
882082:570::/282082:57f:ffff:ffff:ffff:ffff:ffff:ffff
892082:580::/282082:58f:ffff:ffff:ffff:ffff:ffff:ffff
902082:590::/282082:59f:ffff:ffff:ffff:ffff:ffff:ffff
912082:5a0::/282082:5af:ffff:ffff:ffff:ffff:ffff:ffff
922082:5b0::/282082:5bf:ffff:ffff:ffff:ffff:ffff:ffff
932082:5c0::/282082:5cf:ffff:ffff:ffff:ffff:ffff:ffff
942082:5d0::/282082:5df:ffff:ffff:ffff:ffff:ffff:ffff
952082:5e0::/282082:5ef:ffff:ffff:ffff:ffff:ffff:ffff
962082:5f0::/282082:5ff:ffff:ffff:ffff:ffff:ffff:ffff
972082:600::/282082:60f:ffff:ffff:ffff:ffff:ffff:ffff
982082:610::/282082:61f:ffff:ffff:ffff:ffff:ffff:ffff
992082:620::/282082:62f:ffff:ffff:ffff:ffff:ffff:ffff
1002082:630::/282082:63f:ffff:ffff:ffff:ffff:ffff:ffff
1012082:640::/282082:64f:ffff:ffff:ffff:ffff:ffff:ffff
1022082:650::/282082:65f:ffff:ffff:ffff:ffff:ffff:ffff
1032082:660::/282082:66f:ffff:ffff:ffff:ffff:ffff:ffff
1042082:670::/282082:67f:ffff:ffff:ffff:ffff:ffff:ffff
1052082:680::/282082:68f:ffff:ffff:ffff:ffff:ffff:ffff
1062082:690::/282082:69f:ffff:ffff:ffff:ffff:ffff:ffff
1072082:6a0::/282082:6af:ffff:ffff:ffff:ffff:ffff:ffff
1082082:6b0::/282082:6bf:ffff:ffff:ffff:ffff:ffff:ffff
1092082:6c0::/282082:6cf:ffff:ffff:ffff:ffff:ffff:ffff
1102082:6d0::/282082:6df:ffff:ffff:ffff:ffff:ffff:ffff
1112082:6e0::/282082:6ef:ffff:ffff:ffff:ffff:ffff:ffff
1122082:6f0::/282082:6ff:ffff:ffff:ffff:ffff:ffff:ffff
1132082:700::/282082:70f:ffff:ffff:ffff:ffff:ffff:ffff
1142082:710::/282082:71f:ffff:ffff:ffff:ffff:ffff:ffff
1152082:720::/282082:72f:ffff:ffff:ffff:ffff:ffff:ffff
1162082:730::/282082:73f:ffff:ffff:ffff:ffff:ffff:ffff
1172082:740::/282082:74f:ffff:ffff:ffff:ffff:ffff:ffff
1182082:750::/282082:75f:ffff:ffff:ffff:ffff:ffff:ffff
1192082:760::/282082:76f:ffff:ffff:ffff:ffff:ffff:ffff
1202082:770::/282082:77f:ffff:ffff:ffff:ffff:ffff:ffff
1212082:780::/282082:78f:ffff:ffff:ffff:ffff:ffff:ffff
1222082:790::/282082:79f:ffff:ffff:ffff:ffff:ffff:ffff
1232082:7a0::/282082:7af:ffff:ffff:ffff:ffff:ffff:ffff
1242082:7b0::/282082:7bf:ffff:ffff:ffff:ffff:ffff:ffff
1252082:7c0::/282082:7cf:ffff:ffff:ffff:ffff:ffff:ffff
1262082:7d0::/282082:7df:ffff:ffff:ffff:ffff:ffff:ffff
1272082:7e0::/282082:7ef:ffff:ffff:ffff:ffff:ffff:ffff
1282082:7f0::/282082:7ff:ffff:ffff:ffff:ffff:ffff:ffff
1292082:800::/282082:80f:ffff:ffff:ffff:ffff:ffff:ffff
1302082:810::/282082:81f:ffff:ffff:ffff:ffff:ffff:ffff
1312082:820::/282082:82f:ffff:ffff:ffff:ffff:ffff:ffff
1322082:830::/282082:83f:ffff:ffff:ffff:ffff:ffff:ffff
1332082:840::/282082:84f:ffff:ffff:ffff:ffff:ffff:ffff
1342082:850::/282082:85f:ffff:ffff:ffff:ffff:ffff:ffff
1352082:860::/282082:86f:ffff:ffff:ffff:ffff:ffff:ffff
1362082:870::/282082:87f:ffff:ffff:ffff:ffff:ffff:ffff
1372082:880::/282082:88f:ffff:ffff:ffff:ffff:ffff:ffff
1382082:890::/282082:89f:ffff:ffff:ffff:ffff:ffff:ffff
1392082:8a0::/282082:8af:ffff:ffff:ffff:ffff:ffff:ffff
1402082:8b0::/282082:8bf:ffff:ffff:ffff:ffff:ffff:ffff
1412082:8c0::/282082:8cf:ffff:ffff:ffff:ffff:ffff:ffff
1422082:8d0::/282082:8df:ffff:ffff:ffff:ffff:ffff:ffff
1432082:8e0::/282082:8ef:ffff:ffff:ffff:ffff:ffff:ffff
1442082:8f0::/282082:8ff:ffff:ffff:ffff:ffff:ffff:ffff
1452082:900::/282082:90f:ffff:ffff:ffff:ffff:ffff:ffff
1462082:910::/282082:91f:ffff:ffff:ffff:ffff:ffff:ffff
1472082:920::/282082:92f:ffff:ffff:ffff:ffff:ffff:ffff
1482082:930::/282082:93f:ffff:ffff:ffff:ffff:ffff:ffff
1492082:940::/282082:94f:ffff:ffff:ffff:ffff:ffff:ffff
1502082:950::/282082:95f:ffff:ffff:ffff:ffff:ffff:ffff
1512082:960::/282082:96f:ffff:ffff:ffff:ffff:ffff:ffff
1522082:970::/282082:97f:ffff:ffff:ffff:ffff:ffff:ffff
1532082:980::/282082:98f:ffff:ffff:ffff:ffff:ffff:ffff
1542082:990::/282082:99f:ffff:ffff:ffff:ffff:ffff:ffff
1552082:9a0::/282082:9af:ffff:ffff:ffff:ffff:ffff:ffff
1562082:9b0::/282082:9bf:ffff:ffff:ffff:ffff:ffff:ffff
1572082:9c0::/282082:9cf:ffff:ffff:ffff:ffff:ffff:ffff
1582082:9d0::/282082:9df:ffff:ffff:ffff:ffff:ffff:ffff
1592082:9e0::/282082:9ef:ffff:ffff:ffff:ffff:ffff:ffff
1602082:9f0::/282082:9ff:ffff:ffff:ffff:ffff:ffff:ffff
1612082:a00::/282082:a0f:ffff:ffff:ffff:ffff:ffff:ffff
1622082:a10::/282082:a1f:ffff:ffff:ffff:ffff:ffff:ffff
1632082:a20::/282082:a2f:ffff:ffff:ffff:ffff:ffff:ffff
1642082:a30::/282082:a3f:ffff:ffff:ffff:ffff:ffff:ffff
1652082:a40::/282082:a4f:ffff:ffff:ffff:ffff:ffff:ffff
1662082:a50::/282082:a5f:ffff:ffff:ffff:ffff:ffff:ffff
1672082:a60::/282082:a6f:ffff:ffff:ffff:ffff:ffff:ffff
1682082:a70::/282082:a7f:ffff:ffff:ffff:ffff:ffff:ffff
1692082:a80::/282082:a8f:ffff:ffff:ffff:ffff:ffff:ffff
1702082:a90::/282082:a9f:ffff:ffff:ffff:ffff:ffff:ffff
1712082:aa0::/282082:aaf:ffff:ffff:ffff:ffff:ffff:ffff
1722082:ab0::/282082:abf:ffff:ffff:ffff:ffff:ffff:ffff
1732082:ac0::/282082:acf:ffff:ffff:ffff:ffff:ffff:ffff
1742082:ad0::/282082:adf:ffff:ffff:ffff:ffff:ffff:ffff
1752082:ae0::/282082:aef:ffff:ffff:ffff:ffff:ffff:ffff
1762082:af0::/282082:aff:ffff:ffff:ffff:ffff:ffff:ffff
1772082:b00::/282082:b0f:ffff:ffff:ffff:ffff:ffff:ffff
1782082:b10::/282082:b1f:ffff:ffff:ffff:ffff:ffff:ffff
1792082:b20::/282082:b2f:ffff:ffff:ffff:ffff:ffff:ffff
1802082:b30::/282082:b3f:ffff:ffff:ffff:ffff:ffff:ffff
1812082:b40::/282082:b4f:ffff:ffff:ffff:ffff:ffff:ffff
1822082:b50::/282082:b5f:ffff:ffff:ffff:ffff:ffff:ffff
1832082:b60::/282082:b6f:ffff:ffff:ffff:ffff:ffff:ffff
1842082:b70::/282082:b7f:ffff:ffff:ffff:ffff:ffff:ffff
1852082:b80::/282082:b8f:ffff:ffff:ffff:ffff:ffff:ffff
1862082:b90::/282082:b9f:ffff:ffff:ffff:ffff:ffff:ffff
1872082:ba0::/282082:baf:ffff:ffff:ffff:ffff:ffff:ffff
1882082:bb0::/282082:bbf:ffff:ffff:ffff:ffff:ffff:ffff
1892082:bc0::/282082:bcf:ffff:ffff:ffff:ffff:ffff:ffff
1902082:bd0::/282082:bdf:ffff:ffff:ffff:ffff:ffff:ffff
1912082:be0::/282082:bef:ffff:ffff:ffff:ffff:ffff:ffff
1922082:bf0::/282082:bff:ffff:ffff:ffff:ffff:ffff:ffff
1932082:c00::/282082:c0f:ffff:ffff:ffff:ffff:ffff:ffff
1942082:c10::/282082:c1f:ffff:ffff:ffff:ffff:ffff:ffff
1952082:c20::/282082:c2f:ffff:ffff:ffff:ffff:ffff:ffff
1962082:c30::/282082:c3f:ffff:ffff:ffff:ffff:ffff:ffff
1972082:c40::/282082:c4f:ffff:ffff:ffff:ffff:ffff:ffff
1982082:c50::/282082:c5f:ffff:ffff:ffff:ffff:ffff:ffff
1992082:c60::/282082:c6f:ffff:ffff:ffff:ffff:ffff:ffff
2002082:c70::/282082:c7f:ffff:ffff:ffff:ffff:ffff:ffff
2012082:c80::/282082:c8f:ffff:ffff:ffff:ffff:ffff:ffff
2022082:c90::/282082:c9f:ffff:ffff:ffff:ffff:ffff:ffff
2032082:ca0::/282082:caf:ffff:ffff:ffff:ffff:ffff:ffff
2042082:cb0::/282082:cbf:ffff:ffff:ffff:ffff:ffff:ffff
2052082:cc0::/282082:ccf:ffff:ffff:ffff:ffff:ffff:ffff
2062082:cd0::/282082:cdf:ffff:ffff:ffff:ffff:ffff:ffff
2072082:ce0::/282082:cef:ffff:ffff:ffff:ffff:ffff:ffff
2082082:cf0::/282082:cff:ffff:ffff:ffff:ffff:ffff:ffff
2092082:d00::/282082:d0f:ffff:ffff:ffff:ffff:ffff:ffff
2102082:d10::/282082:d1f:ffff:ffff:ffff:ffff:ffff:ffff
2112082:d20::/282082:d2f:ffff:ffff:ffff:ffff:ffff:ffff
2122082:d30::/282082:d3f:ffff:ffff:ffff:ffff:ffff:ffff
2132082:d40::/282082:d4f:ffff:ffff:ffff:ffff:ffff:ffff
2142082:d50::/282082:d5f:ffff:ffff:ffff:ffff:ffff:ffff
2152082:d60::/282082:d6f:ffff:ffff:ffff:ffff:ffff:ffff
2162082:d70::/282082:d7f:ffff:ffff:ffff:ffff:ffff:ffff
2172082:d80::/282082:d8f:ffff:ffff:ffff:ffff:ffff:ffff
2182082:d90::/282082:d9f:ffff:ffff:ffff:ffff:ffff:ffff
2192082:da0::/282082:daf:ffff:ffff:ffff:ffff:ffff:ffff
2202082:db0::/282082:dbf:ffff:ffff:ffff:ffff:ffff:ffff
2212082:dc0::/282082:dcf:ffff:ffff:ffff:ffff:ffff:ffff
2222082:dd0::/282082:ddf:ffff:ffff:ffff:ffff:ffff:ffff
2232082:de0::/282082:def:ffff:ffff:ffff:ffff:ffff:ffff
2242082:df0::/282082:dff:ffff:ffff:ffff:ffff:ffff:ffff
2252082:e00::/282082:e0f:ffff:ffff:ffff:ffff:ffff:ffff
2262082:e10::/282082:e1f:ffff:ffff:ffff:ffff:ffff:ffff
2272082:e20::/282082:e2f:ffff:ffff:ffff:ffff:ffff:ffff
2282082:e30::/282082:e3f:ffff:ffff:ffff:ffff:ffff:ffff
2292082:e40::/282082:e4f:ffff:ffff:ffff:ffff:ffff:ffff
2302082:e50::/282082:e5f:ffff:ffff:ffff:ffff:ffff:ffff
2312082:e60::/282082:e6f:ffff:ffff:ffff:ffff:ffff:ffff
2322082:e70::/282082:e7f:ffff:ffff:ffff:ffff:ffff:ffff
2332082:e80::/282082:e8f:ffff:ffff:ffff:ffff:ffff:ffff
2342082:e90::/282082:e9f:ffff:ffff:ffff:ffff:ffff:ffff
2352082:ea0::/282082:eaf:ffff:ffff:ffff:ffff:ffff:ffff
2362082:eb0::/282082:ebf:ffff:ffff:ffff:ffff:ffff:ffff
2372082:ec0::/282082:ecf:ffff:ffff:ffff:ffff:ffff:ffff
2382082:ed0::/282082:edf:ffff:ffff:ffff:ffff:ffff:ffff
2392082:ee0::/282082:eef:ffff:ffff:ffff:ffff:ffff:ffff
2402082:ef0::/282082:eff:ffff:ffff:ffff:ffff:ffff:ffff
2412082:f00::/282082:f0f:ffff:ffff:ffff:ffff:ffff:ffff
2422082:f10::/282082:f1f:ffff:ffff:ffff:ffff:ffff:ffff
2432082:f20::/282082:f2f:ffff:ffff:ffff:ffff:ffff:ffff
2442082:f30::/282082:f3f:ffff:ffff:ffff:ffff:ffff:ffff
2452082:f40::/282082:f4f:ffff:ffff:ffff:ffff:ffff:ffff
2462082:f50::/282082:f5f:ffff:ffff:ffff:ffff:ffff:ffff
2472082:f60::/282082:f6f:ffff:ffff:ffff:ffff:ffff:ffff
2482082:f70::/282082:f7f:ffff:ffff:ffff:ffff:ffff:ffff
2492082:f80::/282082:f8f:ffff:ffff:ffff:ffff:ffff:ffff
2502082:f90::/282082:f9f:ffff:ffff:ffff:ffff:ffff:ffff
2512082:fa0::/282082:faf:ffff:ffff:ffff:ffff:ffff:ffff
2522082:fb0::/282082:fbf:ffff:ffff:ffff:ffff:ffff:ffff
2532082:fc0::/282082:fcf:ffff:ffff:ffff:ffff:ffff:ffff
2542082:fd0::/282082:fdf:ffff:ffff:ffff:ffff:ffff:ffff
2552082:fe0::/282082:fef:ffff:ffff:ffff:ffff:ffff:ffff
2562082:ff0::/282082: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.