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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
2067::/16
First address
2067::
Last address
2067: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
2067:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
7.6.0.2.ip6.arpa
Split into smaller subnets/28
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

2067::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
12067::/282067:f:ffff:ffff:ffff:ffff:ffff:ffff
22067:10::/282067:1f:ffff:ffff:ffff:ffff:ffff:ffff
32067:20::/282067:2f:ffff:ffff:ffff:ffff:ffff:ffff
42067:30::/282067:3f:ffff:ffff:ffff:ffff:ffff:ffff
52067:40::/282067:4f:ffff:ffff:ffff:ffff:ffff:ffff
62067:50::/282067:5f:ffff:ffff:ffff:ffff:ffff:ffff
72067:60::/282067:6f:ffff:ffff:ffff:ffff:ffff:ffff
82067:70::/282067:7f:ffff:ffff:ffff:ffff:ffff:ffff
92067:80::/282067:8f:ffff:ffff:ffff:ffff:ffff:ffff
102067:90::/282067:9f:ffff:ffff:ffff:ffff:ffff:ffff
112067:a0::/282067:af:ffff:ffff:ffff:ffff:ffff:ffff
122067:b0::/282067:bf:ffff:ffff:ffff:ffff:ffff:ffff
132067:c0::/282067:cf:ffff:ffff:ffff:ffff:ffff:ffff
142067:d0::/282067:df:ffff:ffff:ffff:ffff:ffff:ffff
152067:e0::/282067:ef:ffff:ffff:ffff:ffff:ffff:ffff
162067:f0::/282067:ff:ffff:ffff:ffff:ffff:ffff:ffff
172067:100::/282067:10f:ffff:ffff:ffff:ffff:ffff:ffff
182067:110::/282067:11f:ffff:ffff:ffff:ffff:ffff:ffff
192067:120::/282067:12f:ffff:ffff:ffff:ffff:ffff:ffff
202067:130::/282067:13f:ffff:ffff:ffff:ffff:ffff:ffff
212067:140::/282067:14f:ffff:ffff:ffff:ffff:ffff:ffff
222067:150::/282067:15f:ffff:ffff:ffff:ffff:ffff:ffff
232067:160::/282067:16f:ffff:ffff:ffff:ffff:ffff:ffff
242067:170::/282067:17f:ffff:ffff:ffff:ffff:ffff:ffff
252067:180::/282067:18f:ffff:ffff:ffff:ffff:ffff:ffff
262067:190::/282067:19f:ffff:ffff:ffff:ffff:ffff:ffff
272067:1a0::/282067:1af:ffff:ffff:ffff:ffff:ffff:ffff
282067:1b0::/282067:1bf:ffff:ffff:ffff:ffff:ffff:ffff
292067:1c0::/282067:1cf:ffff:ffff:ffff:ffff:ffff:ffff
302067:1d0::/282067:1df:ffff:ffff:ffff:ffff:ffff:ffff
312067:1e0::/282067:1ef:ffff:ffff:ffff:ffff:ffff:ffff
322067:1f0::/282067:1ff:ffff:ffff:ffff:ffff:ffff:ffff
332067:200::/282067:20f:ffff:ffff:ffff:ffff:ffff:ffff
342067:210::/282067:21f:ffff:ffff:ffff:ffff:ffff:ffff
352067:220::/282067:22f:ffff:ffff:ffff:ffff:ffff:ffff
362067:230::/282067:23f:ffff:ffff:ffff:ffff:ffff:ffff
372067:240::/282067:24f:ffff:ffff:ffff:ffff:ffff:ffff
382067:250::/282067:25f:ffff:ffff:ffff:ffff:ffff:ffff
392067:260::/282067:26f:ffff:ffff:ffff:ffff:ffff:ffff
402067:270::/282067:27f:ffff:ffff:ffff:ffff:ffff:ffff
412067:280::/282067:28f:ffff:ffff:ffff:ffff:ffff:ffff
422067:290::/282067:29f:ffff:ffff:ffff:ffff:ffff:ffff
432067:2a0::/282067:2af:ffff:ffff:ffff:ffff:ffff:ffff
442067:2b0::/282067:2bf:ffff:ffff:ffff:ffff:ffff:ffff
452067:2c0::/282067:2cf:ffff:ffff:ffff:ffff:ffff:ffff
462067:2d0::/282067:2df:ffff:ffff:ffff:ffff:ffff:ffff
472067:2e0::/282067:2ef:ffff:ffff:ffff:ffff:ffff:ffff
482067:2f0::/282067:2ff:ffff:ffff:ffff:ffff:ffff:ffff
492067:300::/282067:30f:ffff:ffff:ffff:ffff:ffff:ffff
502067:310::/282067:31f:ffff:ffff:ffff:ffff:ffff:ffff
512067:320::/282067:32f:ffff:ffff:ffff:ffff:ffff:ffff
522067:330::/282067:33f:ffff:ffff:ffff:ffff:ffff:ffff
532067:340::/282067:34f:ffff:ffff:ffff:ffff:ffff:ffff
542067:350::/282067:35f:ffff:ffff:ffff:ffff:ffff:ffff
552067:360::/282067:36f:ffff:ffff:ffff:ffff:ffff:ffff
562067:370::/282067:37f:ffff:ffff:ffff:ffff:ffff:ffff
572067:380::/282067:38f:ffff:ffff:ffff:ffff:ffff:ffff
582067:390::/282067:39f:ffff:ffff:ffff:ffff:ffff:ffff
592067:3a0::/282067:3af:ffff:ffff:ffff:ffff:ffff:ffff
602067:3b0::/282067:3bf:ffff:ffff:ffff:ffff:ffff:ffff
612067:3c0::/282067:3cf:ffff:ffff:ffff:ffff:ffff:ffff
622067:3d0::/282067:3df:ffff:ffff:ffff:ffff:ffff:ffff
632067:3e0::/282067:3ef:ffff:ffff:ffff:ffff:ffff:ffff
642067:3f0::/282067:3ff:ffff:ffff:ffff:ffff:ffff:ffff
652067:400::/282067:40f:ffff:ffff:ffff:ffff:ffff:ffff
662067:410::/282067:41f:ffff:ffff:ffff:ffff:ffff:ffff
672067:420::/282067:42f:ffff:ffff:ffff:ffff:ffff:ffff
682067:430::/282067:43f:ffff:ffff:ffff:ffff:ffff:ffff
692067:440::/282067:44f:ffff:ffff:ffff:ffff:ffff:ffff
702067:450::/282067:45f:ffff:ffff:ffff:ffff:ffff:ffff
712067:460::/282067:46f:ffff:ffff:ffff:ffff:ffff:ffff
722067:470::/282067:47f:ffff:ffff:ffff:ffff:ffff:ffff
732067:480::/282067:48f:ffff:ffff:ffff:ffff:ffff:ffff
742067:490::/282067:49f:ffff:ffff:ffff:ffff:ffff:ffff
752067:4a0::/282067:4af:ffff:ffff:ffff:ffff:ffff:ffff
762067:4b0::/282067:4bf:ffff:ffff:ffff:ffff:ffff:ffff
772067:4c0::/282067:4cf:ffff:ffff:ffff:ffff:ffff:ffff
782067:4d0::/282067:4df:ffff:ffff:ffff:ffff:ffff:ffff
792067:4e0::/282067:4ef:ffff:ffff:ffff:ffff:ffff:ffff
802067:4f0::/282067:4ff:ffff:ffff:ffff:ffff:ffff:ffff
812067:500::/282067:50f:ffff:ffff:ffff:ffff:ffff:ffff
822067:510::/282067:51f:ffff:ffff:ffff:ffff:ffff:ffff
832067:520::/282067:52f:ffff:ffff:ffff:ffff:ffff:ffff
842067:530::/282067:53f:ffff:ffff:ffff:ffff:ffff:ffff
852067:540::/282067:54f:ffff:ffff:ffff:ffff:ffff:ffff
862067:550::/282067:55f:ffff:ffff:ffff:ffff:ffff:ffff
872067:560::/282067:56f:ffff:ffff:ffff:ffff:ffff:ffff
882067:570::/282067:57f:ffff:ffff:ffff:ffff:ffff:ffff
892067:580::/282067:58f:ffff:ffff:ffff:ffff:ffff:ffff
902067:590::/282067:59f:ffff:ffff:ffff:ffff:ffff:ffff
912067:5a0::/282067:5af:ffff:ffff:ffff:ffff:ffff:ffff
922067:5b0::/282067:5bf:ffff:ffff:ffff:ffff:ffff:ffff
932067:5c0::/282067:5cf:ffff:ffff:ffff:ffff:ffff:ffff
942067:5d0::/282067:5df:ffff:ffff:ffff:ffff:ffff:ffff
952067:5e0::/282067:5ef:ffff:ffff:ffff:ffff:ffff:ffff
962067:5f0::/282067:5ff:ffff:ffff:ffff:ffff:ffff:ffff
972067:600::/282067:60f:ffff:ffff:ffff:ffff:ffff:ffff
982067:610::/282067:61f:ffff:ffff:ffff:ffff:ffff:ffff
992067:620::/282067:62f:ffff:ffff:ffff:ffff:ffff:ffff
1002067:630::/282067:63f:ffff:ffff:ffff:ffff:ffff:ffff
1012067:640::/282067:64f:ffff:ffff:ffff:ffff:ffff:ffff
1022067:650::/282067:65f:ffff:ffff:ffff:ffff:ffff:ffff
1032067:660::/282067:66f:ffff:ffff:ffff:ffff:ffff:ffff
1042067:670::/282067:67f:ffff:ffff:ffff:ffff:ffff:ffff
1052067:680::/282067:68f:ffff:ffff:ffff:ffff:ffff:ffff
1062067:690::/282067:69f:ffff:ffff:ffff:ffff:ffff:ffff
1072067:6a0::/282067:6af:ffff:ffff:ffff:ffff:ffff:ffff
1082067:6b0::/282067:6bf:ffff:ffff:ffff:ffff:ffff:ffff
1092067:6c0::/282067:6cf:ffff:ffff:ffff:ffff:ffff:ffff
1102067:6d0::/282067:6df:ffff:ffff:ffff:ffff:ffff:ffff
1112067:6e0::/282067:6ef:ffff:ffff:ffff:ffff:ffff:ffff
1122067:6f0::/282067:6ff:ffff:ffff:ffff:ffff:ffff:ffff
1132067:700::/282067:70f:ffff:ffff:ffff:ffff:ffff:ffff
1142067:710::/282067:71f:ffff:ffff:ffff:ffff:ffff:ffff
1152067:720::/282067:72f:ffff:ffff:ffff:ffff:ffff:ffff
1162067:730::/282067:73f:ffff:ffff:ffff:ffff:ffff:ffff
1172067:740::/282067:74f:ffff:ffff:ffff:ffff:ffff:ffff
1182067:750::/282067:75f:ffff:ffff:ffff:ffff:ffff:ffff
1192067:760::/282067:76f:ffff:ffff:ffff:ffff:ffff:ffff
1202067:770::/282067:77f:ffff:ffff:ffff:ffff:ffff:ffff
1212067:780::/282067:78f:ffff:ffff:ffff:ffff:ffff:ffff
1222067:790::/282067:79f:ffff:ffff:ffff:ffff:ffff:ffff
1232067:7a0::/282067:7af:ffff:ffff:ffff:ffff:ffff:ffff
1242067:7b0::/282067:7bf:ffff:ffff:ffff:ffff:ffff:ffff
1252067:7c0::/282067:7cf:ffff:ffff:ffff:ffff:ffff:ffff
1262067:7d0::/282067:7df:ffff:ffff:ffff:ffff:ffff:ffff
1272067:7e0::/282067:7ef:ffff:ffff:ffff:ffff:ffff:ffff
1282067:7f0::/282067:7ff:ffff:ffff:ffff:ffff:ffff:ffff
1292067:800::/282067:80f:ffff:ffff:ffff:ffff:ffff:ffff
1302067:810::/282067:81f:ffff:ffff:ffff:ffff:ffff:ffff
1312067:820::/282067:82f:ffff:ffff:ffff:ffff:ffff:ffff
1322067:830::/282067:83f:ffff:ffff:ffff:ffff:ffff:ffff
1332067:840::/282067:84f:ffff:ffff:ffff:ffff:ffff:ffff
1342067:850::/282067:85f:ffff:ffff:ffff:ffff:ffff:ffff
1352067:860::/282067:86f:ffff:ffff:ffff:ffff:ffff:ffff
1362067:870::/282067:87f:ffff:ffff:ffff:ffff:ffff:ffff
1372067:880::/282067:88f:ffff:ffff:ffff:ffff:ffff:ffff
1382067:890::/282067:89f:ffff:ffff:ffff:ffff:ffff:ffff
1392067:8a0::/282067:8af:ffff:ffff:ffff:ffff:ffff:ffff
1402067:8b0::/282067:8bf:ffff:ffff:ffff:ffff:ffff:ffff
1412067:8c0::/282067:8cf:ffff:ffff:ffff:ffff:ffff:ffff
1422067:8d0::/282067:8df:ffff:ffff:ffff:ffff:ffff:ffff
1432067:8e0::/282067:8ef:ffff:ffff:ffff:ffff:ffff:ffff
1442067:8f0::/282067:8ff:ffff:ffff:ffff:ffff:ffff:ffff
1452067:900::/282067:90f:ffff:ffff:ffff:ffff:ffff:ffff
1462067:910::/282067:91f:ffff:ffff:ffff:ffff:ffff:ffff
1472067:920::/282067:92f:ffff:ffff:ffff:ffff:ffff:ffff
1482067:930::/282067:93f:ffff:ffff:ffff:ffff:ffff:ffff
1492067:940::/282067:94f:ffff:ffff:ffff:ffff:ffff:ffff
1502067:950::/282067:95f:ffff:ffff:ffff:ffff:ffff:ffff
1512067:960::/282067:96f:ffff:ffff:ffff:ffff:ffff:ffff
1522067:970::/282067:97f:ffff:ffff:ffff:ffff:ffff:ffff
1532067:980::/282067:98f:ffff:ffff:ffff:ffff:ffff:ffff
1542067:990::/282067:99f:ffff:ffff:ffff:ffff:ffff:ffff
1552067:9a0::/282067:9af:ffff:ffff:ffff:ffff:ffff:ffff
1562067:9b0::/282067:9bf:ffff:ffff:ffff:ffff:ffff:ffff
1572067:9c0::/282067:9cf:ffff:ffff:ffff:ffff:ffff:ffff
1582067:9d0::/282067:9df:ffff:ffff:ffff:ffff:ffff:ffff
1592067:9e0::/282067:9ef:ffff:ffff:ffff:ffff:ffff:ffff
1602067:9f0::/282067:9ff:ffff:ffff:ffff:ffff:ffff:ffff
1612067:a00::/282067:a0f:ffff:ffff:ffff:ffff:ffff:ffff
1622067:a10::/282067:a1f:ffff:ffff:ffff:ffff:ffff:ffff
1632067:a20::/282067:a2f:ffff:ffff:ffff:ffff:ffff:ffff
1642067:a30::/282067:a3f:ffff:ffff:ffff:ffff:ffff:ffff
1652067:a40::/282067:a4f:ffff:ffff:ffff:ffff:ffff:ffff
1662067:a50::/282067:a5f:ffff:ffff:ffff:ffff:ffff:ffff
1672067:a60::/282067:a6f:ffff:ffff:ffff:ffff:ffff:ffff
1682067:a70::/282067:a7f:ffff:ffff:ffff:ffff:ffff:ffff
1692067:a80::/282067:a8f:ffff:ffff:ffff:ffff:ffff:ffff
1702067:a90::/282067:a9f:ffff:ffff:ffff:ffff:ffff:ffff
1712067:aa0::/282067:aaf:ffff:ffff:ffff:ffff:ffff:ffff
1722067:ab0::/282067:abf:ffff:ffff:ffff:ffff:ffff:ffff
1732067:ac0::/282067:acf:ffff:ffff:ffff:ffff:ffff:ffff
1742067:ad0::/282067:adf:ffff:ffff:ffff:ffff:ffff:ffff
1752067:ae0::/282067:aef:ffff:ffff:ffff:ffff:ffff:ffff
1762067:af0::/282067:aff:ffff:ffff:ffff:ffff:ffff:ffff
1772067:b00::/282067:b0f:ffff:ffff:ffff:ffff:ffff:ffff
1782067:b10::/282067:b1f:ffff:ffff:ffff:ffff:ffff:ffff
1792067:b20::/282067:b2f:ffff:ffff:ffff:ffff:ffff:ffff
1802067:b30::/282067:b3f:ffff:ffff:ffff:ffff:ffff:ffff
1812067:b40::/282067:b4f:ffff:ffff:ffff:ffff:ffff:ffff
1822067:b50::/282067:b5f:ffff:ffff:ffff:ffff:ffff:ffff
1832067:b60::/282067:b6f:ffff:ffff:ffff:ffff:ffff:ffff
1842067:b70::/282067:b7f:ffff:ffff:ffff:ffff:ffff:ffff
1852067:b80::/282067:b8f:ffff:ffff:ffff:ffff:ffff:ffff
1862067:b90::/282067:b9f:ffff:ffff:ffff:ffff:ffff:ffff
1872067:ba0::/282067:baf:ffff:ffff:ffff:ffff:ffff:ffff
1882067:bb0::/282067:bbf:ffff:ffff:ffff:ffff:ffff:ffff
1892067:bc0::/282067:bcf:ffff:ffff:ffff:ffff:ffff:ffff
1902067:bd0::/282067:bdf:ffff:ffff:ffff:ffff:ffff:ffff
1912067:be0::/282067:bef:ffff:ffff:ffff:ffff:ffff:ffff
1922067:bf0::/282067:bff:ffff:ffff:ffff:ffff:ffff:ffff
1932067:c00::/282067:c0f:ffff:ffff:ffff:ffff:ffff:ffff
1942067:c10::/282067:c1f:ffff:ffff:ffff:ffff:ffff:ffff
1952067:c20::/282067:c2f:ffff:ffff:ffff:ffff:ffff:ffff
1962067:c30::/282067:c3f:ffff:ffff:ffff:ffff:ffff:ffff
1972067:c40::/282067:c4f:ffff:ffff:ffff:ffff:ffff:ffff
1982067:c50::/282067:c5f:ffff:ffff:ffff:ffff:ffff:ffff
1992067:c60::/282067:c6f:ffff:ffff:ffff:ffff:ffff:ffff
2002067:c70::/282067:c7f:ffff:ffff:ffff:ffff:ffff:ffff
2012067:c80::/282067:c8f:ffff:ffff:ffff:ffff:ffff:ffff
2022067:c90::/282067:c9f:ffff:ffff:ffff:ffff:ffff:ffff
2032067:ca0::/282067:caf:ffff:ffff:ffff:ffff:ffff:ffff
2042067:cb0::/282067:cbf:ffff:ffff:ffff:ffff:ffff:ffff
2052067:cc0::/282067:ccf:ffff:ffff:ffff:ffff:ffff:ffff
2062067:cd0::/282067:cdf:ffff:ffff:ffff:ffff:ffff:ffff
2072067:ce0::/282067:cef:ffff:ffff:ffff:ffff:ffff:ffff
2082067:cf0::/282067:cff:ffff:ffff:ffff:ffff:ffff:ffff
2092067:d00::/282067:d0f:ffff:ffff:ffff:ffff:ffff:ffff
2102067:d10::/282067:d1f:ffff:ffff:ffff:ffff:ffff:ffff
2112067:d20::/282067:d2f:ffff:ffff:ffff:ffff:ffff:ffff
2122067:d30::/282067:d3f:ffff:ffff:ffff:ffff:ffff:ffff
2132067:d40::/282067:d4f:ffff:ffff:ffff:ffff:ffff:ffff
2142067:d50::/282067:d5f:ffff:ffff:ffff:ffff:ffff:ffff
2152067:d60::/282067:d6f:ffff:ffff:ffff:ffff:ffff:ffff
2162067:d70::/282067:d7f:ffff:ffff:ffff:ffff:ffff:ffff
2172067:d80::/282067:d8f:ffff:ffff:ffff:ffff:ffff:ffff
2182067:d90::/282067:d9f:ffff:ffff:ffff:ffff:ffff:ffff
2192067:da0::/282067:daf:ffff:ffff:ffff:ffff:ffff:ffff
2202067:db0::/282067:dbf:ffff:ffff:ffff:ffff:ffff:ffff
2212067:dc0::/282067:dcf:ffff:ffff:ffff:ffff:ffff:ffff
2222067:dd0::/282067:ddf:ffff:ffff:ffff:ffff:ffff:ffff
2232067:de0::/282067:def:ffff:ffff:ffff:ffff:ffff:ffff
2242067:df0::/282067:dff:ffff:ffff:ffff:ffff:ffff:ffff
2252067:e00::/282067:e0f:ffff:ffff:ffff:ffff:ffff:ffff
2262067:e10::/282067:e1f:ffff:ffff:ffff:ffff:ffff:ffff
2272067:e20::/282067:e2f:ffff:ffff:ffff:ffff:ffff:ffff
2282067:e30::/282067:e3f:ffff:ffff:ffff:ffff:ffff:ffff
2292067:e40::/282067:e4f:ffff:ffff:ffff:ffff:ffff:ffff
2302067:e50::/282067:e5f:ffff:ffff:ffff:ffff:ffff:ffff
2312067:e60::/282067:e6f:ffff:ffff:ffff:ffff:ffff:ffff
2322067:e70::/282067:e7f:ffff:ffff:ffff:ffff:ffff:ffff
2332067:e80::/282067:e8f:ffff:ffff:ffff:ffff:ffff:ffff
2342067:e90::/282067:e9f:ffff:ffff:ffff:ffff:ffff:ffff
2352067:ea0::/282067:eaf:ffff:ffff:ffff:ffff:ffff:ffff
2362067:eb0::/282067:ebf:ffff:ffff:ffff:ffff:ffff:ffff
2372067:ec0::/282067:ecf:ffff:ffff:ffff:ffff:ffff:ffff
2382067:ed0::/282067:edf:ffff:ffff:ffff:ffff:ffff:ffff
2392067:ee0::/282067:eef:ffff:ffff:ffff:ffff:ffff:ffff
2402067:ef0::/282067:eff:ffff:ffff:ffff:ffff:ffff:ffff
2412067:f00::/282067:f0f:ffff:ffff:ffff:ffff:ffff:ffff
2422067:f10::/282067:f1f:ffff:ffff:ffff:ffff:ffff:ffff
2432067:f20::/282067:f2f:ffff:ffff:ffff:ffff:ffff:ffff
2442067:f30::/282067:f3f:ffff:ffff:ffff:ffff:ffff:ffff
2452067:f40::/282067:f4f:ffff:ffff:ffff:ffff:ffff:ffff
2462067:f50::/282067:f5f:ffff:ffff:ffff:ffff:ffff:ffff
2472067:f60::/282067:f6f:ffff:ffff:ffff:ffff:ffff:ffff
2482067:f70::/282067:f7f:ffff:ffff:ffff:ffff:ffff:ffff
2492067:f80::/282067:f8f:ffff:ffff:ffff:ffff:ffff:ffff
2502067:f90::/282067:f9f:ffff:ffff:ffff:ffff:ffff:ffff
2512067:fa0::/282067:faf:ffff:ffff:ffff:ffff:ffff:ffff
2522067:fb0::/282067:fbf:ffff:ffff:ffff:ffff:ffff:ffff
2532067:fc0::/282067:fcf:ffff:ffff:ffff:ffff:ffff:ffff
2542067:fd0::/282067:fdf:ffff:ffff:ffff:ffff:ffff:ffff
2552067:fe0::/282067:fef:ffff:ffff:ffff:ffff:ffff:ffff
2562067:ff0::/282067: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.