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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
2ec0::/12
First address
2ec0::
Last address
2ecf: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
2ec0:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
c.e.2.ip6.arpa
Split into smaller subnets/28
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2ec0::/12 makes 65,536 subnets of /28; the first 256 are listed.

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