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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
2e22::/16
First address
2e22::
Last address
2e22: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
2e22:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.2.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)

2e22::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
12e22::/282e22:f:ffff:ffff:ffff:ffff:ffff:ffff
22e22:10::/282e22:1f:ffff:ffff:ffff:ffff:ffff:ffff
32e22:20::/282e22:2f:ffff:ffff:ffff:ffff:ffff:ffff
42e22:30::/282e22:3f:ffff:ffff:ffff:ffff:ffff:ffff
52e22:40::/282e22:4f:ffff:ffff:ffff:ffff:ffff:ffff
62e22:50::/282e22:5f:ffff:ffff:ffff:ffff:ffff:ffff
72e22:60::/282e22:6f:ffff:ffff:ffff:ffff:ffff:ffff
82e22:70::/282e22:7f:ffff:ffff:ffff:ffff:ffff:ffff
92e22:80::/282e22:8f:ffff:ffff:ffff:ffff:ffff:ffff
102e22:90::/282e22:9f:ffff:ffff:ffff:ffff:ffff:ffff
112e22:a0::/282e22:af:ffff:ffff:ffff:ffff:ffff:ffff
122e22:b0::/282e22:bf:ffff:ffff:ffff:ffff:ffff:ffff
132e22:c0::/282e22:cf:ffff:ffff:ffff:ffff:ffff:ffff
142e22:d0::/282e22:df:ffff:ffff:ffff:ffff:ffff:ffff
152e22:e0::/282e22:ef:ffff:ffff:ffff:ffff:ffff:ffff
162e22:f0::/282e22:ff:ffff:ffff:ffff:ffff:ffff:ffff
172e22:100::/282e22:10f:ffff:ffff:ffff:ffff:ffff:ffff
182e22:110::/282e22:11f:ffff:ffff:ffff:ffff:ffff:ffff
192e22:120::/282e22:12f:ffff:ffff:ffff:ffff:ffff:ffff
202e22:130::/282e22:13f:ffff:ffff:ffff:ffff:ffff:ffff
212e22:140::/282e22:14f:ffff:ffff:ffff:ffff:ffff:ffff
222e22:150::/282e22:15f:ffff:ffff:ffff:ffff:ffff:ffff
232e22:160::/282e22:16f:ffff:ffff:ffff:ffff:ffff:ffff
242e22:170::/282e22:17f:ffff:ffff:ffff:ffff:ffff:ffff
252e22:180::/282e22:18f:ffff:ffff:ffff:ffff:ffff:ffff
262e22:190::/282e22:19f:ffff:ffff:ffff:ffff:ffff:ffff
272e22:1a0::/282e22:1af:ffff:ffff:ffff:ffff:ffff:ffff
282e22:1b0::/282e22:1bf:ffff:ffff:ffff:ffff:ffff:ffff
292e22:1c0::/282e22:1cf:ffff:ffff:ffff:ffff:ffff:ffff
302e22:1d0::/282e22:1df:ffff:ffff:ffff:ffff:ffff:ffff
312e22:1e0::/282e22:1ef:ffff:ffff:ffff:ffff:ffff:ffff
322e22:1f0::/282e22:1ff:ffff:ffff:ffff:ffff:ffff:ffff
332e22:200::/282e22:20f:ffff:ffff:ffff:ffff:ffff:ffff
342e22:210::/282e22:21f:ffff:ffff:ffff:ffff:ffff:ffff
352e22:220::/282e22:22f:ffff:ffff:ffff:ffff:ffff:ffff
362e22:230::/282e22:23f:ffff:ffff:ffff:ffff:ffff:ffff
372e22:240::/282e22:24f:ffff:ffff:ffff:ffff:ffff:ffff
382e22:250::/282e22:25f:ffff:ffff:ffff:ffff:ffff:ffff
392e22:260::/282e22:26f:ffff:ffff:ffff:ffff:ffff:ffff
402e22:270::/282e22:27f:ffff:ffff:ffff:ffff:ffff:ffff
412e22:280::/282e22:28f:ffff:ffff:ffff:ffff:ffff:ffff
422e22:290::/282e22:29f:ffff:ffff:ffff:ffff:ffff:ffff
432e22:2a0::/282e22:2af:ffff:ffff:ffff:ffff:ffff:ffff
442e22:2b0::/282e22:2bf:ffff:ffff:ffff:ffff:ffff:ffff
452e22:2c0::/282e22:2cf:ffff:ffff:ffff:ffff:ffff:ffff
462e22:2d0::/282e22:2df:ffff:ffff:ffff:ffff:ffff:ffff
472e22:2e0::/282e22:2ef:ffff:ffff:ffff:ffff:ffff:ffff
482e22:2f0::/282e22:2ff:ffff:ffff:ffff:ffff:ffff:ffff
492e22:300::/282e22:30f:ffff:ffff:ffff:ffff:ffff:ffff
502e22:310::/282e22:31f:ffff:ffff:ffff:ffff:ffff:ffff
512e22:320::/282e22:32f:ffff:ffff:ffff:ffff:ffff:ffff
522e22:330::/282e22:33f:ffff:ffff:ffff:ffff:ffff:ffff
532e22:340::/282e22:34f:ffff:ffff:ffff:ffff:ffff:ffff
542e22:350::/282e22:35f:ffff:ffff:ffff:ffff:ffff:ffff
552e22:360::/282e22:36f:ffff:ffff:ffff:ffff:ffff:ffff
562e22:370::/282e22:37f:ffff:ffff:ffff:ffff:ffff:ffff
572e22:380::/282e22:38f:ffff:ffff:ffff:ffff:ffff:ffff
582e22:390::/282e22:39f:ffff:ffff:ffff:ffff:ffff:ffff
592e22:3a0::/282e22:3af:ffff:ffff:ffff:ffff:ffff:ffff
602e22:3b0::/282e22:3bf:ffff:ffff:ffff:ffff:ffff:ffff
612e22:3c0::/282e22:3cf:ffff:ffff:ffff:ffff:ffff:ffff
622e22:3d0::/282e22:3df:ffff:ffff:ffff:ffff:ffff:ffff
632e22:3e0::/282e22:3ef:ffff:ffff:ffff:ffff:ffff:ffff
642e22:3f0::/282e22:3ff:ffff:ffff:ffff:ffff:ffff:ffff
652e22:400::/282e22:40f:ffff:ffff:ffff:ffff:ffff:ffff
662e22:410::/282e22:41f:ffff:ffff:ffff:ffff:ffff:ffff
672e22:420::/282e22:42f:ffff:ffff:ffff:ffff:ffff:ffff
682e22:430::/282e22:43f:ffff:ffff:ffff:ffff:ffff:ffff
692e22:440::/282e22:44f:ffff:ffff:ffff:ffff:ffff:ffff
702e22:450::/282e22:45f:ffff:ffff:ffff:ffff:ffff:ffff
712e22:460::/282e22:46f:ffff:ffff:ffff:ffff:ffff:ffff
722e22:470::/282e22:47f:ffff:ffff:ffff:ffff:ffff:ffff
732e22:480::/282e22:48f:ffff:ffff:ffff:ffff:ffff:ffff
742e22:490::/282e22:49f:ffff:ffff:ffff:ffff:ffff:ffff
752e22:4a0::/282e22:4af:ffff:ffff:ffff:ffff:ffff:ffff
762e22:4b0::/282e22:4bf:ffff:ffff:ffff:ffff:ffff:ffff
772e22:4c0::/282e22:4cf:ffff:ffff:ffff:ffff:ffff:ffff
782e22:4d0::/282e22:4df:ffff:ffff:ffff:ffff:ffff:ffff
792e22:4e0::/282e22:4ef:ffff:ffff:ffff:ffff:ffff:ffff
802e22:4f0::/282e22:4ff:ffff:ffff:ffff:ffff:ffff:ffff
812e22:500::/282e22:50f:ffff:ffff:ffff:ffff:ffff:ffff
822e22:510::/282e22:51f:ffff:ffff:ffff:ffff:ffff:ffff
832e22:520::/282e22:52f:ffff:ffff:ffff:ffff:ffff:ffff
842e22:530::/282e22:53f:ffff:ffff:ffff:ffff:ffff:ffff
852e22:540::/282e22:54f:ffff:ffff:ffff:ffff:ffff:ffff
862e22:550::/282e22:55f:ffff:ffff:ffff:ffff:ffff:ffff
872e22:560::/282e22:56f:ffff:ffff:ffff:ffff:ffff:ffff
882e22:570::/282e22:57f:ffff:ffff:ffff:ffff:ffff:ffff
892e22:580::/282e22:58f:ffff:ffff:ffff:ffff:ffff:ffff
902e22:590::/282e22:59f:ffff:ffff:ffff:ffff:ffff:ffff
912e22:5a0::/282e22:5af:ffff:ffff:ffff:ffff:ffff:ffff
922e22:5b0::/282e22:5bf:ffff:ffff:ffff:ffff:ffff:ffff
932e22:5c0::/282e22:5cf:ffff:ffff:ffff:ffff:ffff:ffff
942e22:5d0::/282e22:5df:ffff:ffff:ffff:ffff:ffff:ffff
952e22:5e0::/282e22:5ef:ffff:ffff:ffff:ffff:ffff:ffff
962e22:5f0::/282e22:5ff:ffff:ffff:ffff:ffff:ffff:ffff
972e22:600::/282e22:60f:ffff:ffff:ffff:ffff:ffff:ffff
982e22:610::/282e22:61f:ffff:ffff:ffff:ffff:ffff:ffff
992e22:620::/282e22:62f:ffff:ffff:ffff:ffff:ffff:ffff
1002e22:630::/282e22:63f:ffff:ffff:ffff:ffff:ffff:ffff
1012e22:640::/282e22:64f:ffff:ffff:ffff:ffff:ffff:ffff
1022e22:650::/282e22:65f:ffff:ffff:ffff:ffff:ffff:ffff
1032e22:660::/282e22:66f:ffff:ffff:ffff:ffff:ffff:ffff
1042e22:670::/282e22:67f:ffff:ffff:ffff:ffff:ffff:ffff
1052e22:680::/282e22:68f:ffff:ffff:ffff:ffff:ffff:ffff
1062e22:690::/282e22:69f:ffff:ffff:ffff:ffff:ffff:ffff
1072e22:6a0::/282e22:6af:ffff:ffff:ffff:ffff:ffff:ffff
1082e22:6b0::/282e22:6bf:ffff:ffff:ffff:ffff:ffff:ffff
1092e22:6c0::/282e22:6cf:ffff:ffff:ffff:ffff:ffff:ffff
1102e22:6d0::/282e22:6df:ffff:ffff:ffff:ffff:ffff:ffff
1112e22:6e0::/282e22:6ef:ffff:ffff:ffff:ffff:ffff:ffff
1122e22:6f0::/282e22:6ff:ffff:ffff:ffff:ffff:ffff:ffff
1132e22:700::/282e22:70f:ffff:ffff:ffff:ffff:ffff:ffff
1142e22:710::/282e22:71f:ffff:ffff:ffff:ffff:ffff:ffff
1152e22:720::/282e22:72f:ffff:ffff:ffff:ffff:ffff:ffff
1162e22:730::/282e22:73f:ffff:ffff:ffff:ffff:ffff:ffff
1172e22:740::/282e22:74f:ffff:ffff:ffff:ffff:ffff:ffff
1182e22:750::/282e22:75f:ffff:ffff:ffff:ffff:ffff:ffff
1192e22:760::/282e22:76f:ffff:ffff:ffff:ffff:ffff:ffff
1202e22:770::/282e22:77f:ffff:ffff:ffff:ffff:ffff:ffff
1212e22:780::/282e22:78f:ffff:ffff:ffff:ffff:ffff:ffff
1222e22:790::/282e22:79f:ffff:ffff:ffff:ffff:ffff:ffff
1232e22:7a0::/282e22:7af:ffff:ffff:ffff:ffff:ffff:ffff
1242e22:7b0::/282e22:7bf:ffff:ffff:ffff:ffff:ffff:ffff
1252e22:7c0::/282e22:7cf:ffff:ffff:ffff:ffff:ffff:ffff
1262e22:7d0::/282e22:7df:ffff:ffff:ffff:ffff:ffff:ffff
1272e22:7e0::/282e22:7ef:ffff:ffff:ffff:ffff:ffff:ffff
1282e22:7f0::/282e22:7ff:ffff:ffff:ffff:ffff:ffff:ffff
1292e22:800::/282e22:80f:ffff:ffff:ffff:ffff:ffff:ffff
1302e22:810::/282e22:81f:ffff:ffff:ffff:ffff:ffff:ffff
1312e22:820::/282e22:82f:ffff:ffff:ffff:ffff:ffff:ffff
1322e22:830::/282e22:83f:ffff:ffff:ffff:ffff:ffff:ffff
1332e22:840::/282e22:84f:ffff:ffff:ffff:ffff:ffff:ffff
1342e22:850::/282e22:85f:ffff:ffff:ffff:ffff:ffff:ffff
1352e22:860::/282e22:86f:ffff:ffff:ffff:ffff:ffff:ffff
1362e22:870::/282e22:87f:ffff:ffff:ffff:ffff:ffff:ffff
1372e22:880::/282e22:88f:ffff:ffff:ffff:ffff:ffff:ffff
1382e22:890::/282e22:89f:ffff:ffff:ffff:ffff:ffff:ffff
1392e22:8a0::/282e22:8af:ffff:ffff:ffff:ffff:ffff:ffff
1402e22:8b0::/282e22:8bf:ffff:ffff:ffff:ffff:ffff:ffff
1412e22:8c0::/282e22:8cf:ffff:ffff:ffff:ffff:ffff:ffff
1422e22:8d0::/282e22:8df:ffff:ffff:ffff:ffff:ffff:ffff
1432e22:8e0::/282e22:8ef:ffff:ffff:ffff:ffff:ffff:ffff
1442e22:8f0::/282e22:8ff:ffff:ffff:ffff:ffff:ffff:ffff
1452e22:900::/282e22:90f:ffff:ffff:ffff:ffff:ffff:ffff
1462e22:910::/282e22:91f:ffff:ffff:ffff:ffff:ffff:ffff
1472e22:920::/282e22:92f:ffff:ffff:ffff:ffff:ffff:ffff
1482e22:930::/282e22:93f:ffff:ffff:ffff:ffff:ffff:ffff
1492e22:940::/282e22:94f:ffff:ffff:ffff:ffff:ffff:ffff
1502e22:950::/282e22:95f:ffff:ffff:ffff:ffff:ffff:ffff
1512e22:960::/282e22:96f:ffff:ffff:ffff:ffff:ffff:ffff
1522e22:970::/282e22:97f:ffff:ffff:ffff:ffff:ffff:ffff
1532e22:980::/282e22:98f:ffff:ffff:ffff:ffff:ffff:ffff
1542e22:990::/282e22:99f:ffff:ffff:ffff:ffff:ffff:ffff
1552e22:9a0::/282e22:9af:ffff:ffff:ffff:ffff:ffff:ffff
1562e22:9b0::/282e22:9bf:ffff:ffff:ffff:ffff:ffff:ffff
1572e22:9c0::/282e22:9cf:ffff:ffff:ffff:ffff:ffff:ffff
1582e22:9d0::/282e22:9df:ffff:ffff:ffff:ffff:ffff:ffff
1592e22:9e0::/282e22:9ef:ffff:ffff:ffff:ffff:ffff:ffff
1602e22:9f0::/282e22:9ff:ffff:ffff:ffff:ffff:ffff:ffff
1612e22:a00::/282e22:a0f:ffff:ffff:ffff:ffff:ffff:ffff
1622e22:a10::/282e22:a1f:ffff:ffff:ffff:ffff:ffff:ffff
1632e22:a20::/282e22:a2f:ffff:ffff:ffff:ffff:ffff:ffff
1642e22:a30::/282e22:a3f:ffff:ffff:ffff:ffff:ffff:ffff
1652e22:a40::/282e22:a4f:ffff:ffff:ffff:ffff:ffff:ffff
1662e22:a50::/282e22:a5f:ffff:ffff:ffff:ffff:ffff:ffff
1672e22:a60::/282e22:a6f:ffff:ffff:ffff:ffff:ffff:ffff
1682e22:a70::/282e22:a7f:ffff:ffff:ffff:ffff:ffff:ffff
1692e22:a80::/282e22:a8f:ffff:ffff:ffff:ffff:ffff:ffff
1702e22:a90::/282e22:a9f:ffff:ffff:ffff:ffff:ffff:ffff
1712e22:aa0::/282e22:aaf:ffff:ffff:ffff:ffff:ffff:ffff
1722e22:ab0::/282e22:abf:ffff:ffff:ffff:ffff:ffff:ffff
1732e22:ac0::/282e22:acf:ffff:ffff:ffff:ffff:ffff:ffff
1742e22:ad0::/282e22:adf:ffff:ffff:ffff:ffff:ffff:ffff
1752e22:ae0::/282e22:aef:ffff:ffff:ffff:ffff:ffff:ffff
1762e22:af0::/282e22:aff:ffff:ffff:ffff:ffff:ffff:ffff
1772e22:b00::/282e22:b0f:ffff:ffff:ffff:ffff:ffff:ffff
1782e22:b10::/282e22:b1f:ffff:ffff:ffff:ffff:ffff:ffff
1792e22:b20::/282e22:b2f:ffff:ffff:ffff:ffff:ffff:ffff
1802e22:b30::/282e22:b3f:ffff:ffff:ffff:ffff:ffff:ffff
1812e22:b40::/282e22:b4f:ffff:ffff:ffff:ffff:ffff:ffff
1822e22:b50::/282e22:b5f:ffff:ffff:ffff:ffff:ffff:ffff
1832e22:b60::/282e22:b6f:ffff:ffff:ffff:ffff:ffff:ffff
1842e22:b70::/282e22:b7f:ffff:ffff:ffff:ffff:ffff:ffff
1852e22:b80::/282e22:b8f:ffff:ffff:ffff:ffff:ffff:ffff
1862e22:b90::/282e22:b9f:ffff:ffff:ffff:ffff:ffff:ffff
1872e22:ba0::/282e22:baf:ffff:ffff:ffff:ffff:ffff:ffff
1882e22:bb0::/282e22:bbf:ffff:ffff:ffff:ffff:ffff:ffff
1892e22:bc0::/282e22:bcf:ffff:ffff:ffff:ffff:ffff:ffff
1902e22:bd0::/282e22:bdf:ffff:ffff:ffff:ffff:ffff:ffff
1912e22:be0::/282e22:bef:ffff:ffff:ffff:ffff:ffff:ffff
1922e22:bf0::/282e22:bff:ffff:ffff:ffff:ffff:ffff:ffff
1932e22:c00::/282e22:c0f:ffff:ffff:ffff:ffff:ffff:ffff
1942e22:c10::/282e22:c1f:ffff:ffff:ffff:ffff:ffff:ffff
1952e22:c20::/282e22:c2f:ffff:ffff:ffff:ffff:ffff:ffff
1962e22:c30::/282e22:c3f:ffff:ffff:ffff:ffff:ffff:ffff
1972e22:c40::/282e22:c4f:ffff:ffff:ffff:ffff:ffff:ffff
1982e22:c50::/282e22:c5f:ffff:ffff:ffff:ffff:ffff:ffff
1992e22:c60::/282e22:c6f:ffff:ffff:ffff:ffff:ffff:ffff
2002e22:c70::/282e22:c7f:ffff:ffff:ffff:ffff:ffff:ffff
2012e22:c80::/282e22:c8f:ffff:ffff:ffff:ffff:ffff:ffff
2022e22:c90::/282e22:c9f:ffff:ffff:ffff:ffff:ffff:ffff
2032e22:ca0::/282e22:caf:ffff:ffff:ffff:ffff:ffff:ffff
2042e22:cb0::/282e22:cbf:ffff:ffff:ffff:ffff:ffff:ffff
2052e22:cc0::/282e22:ccf:ffff:ffff:ffff:ffff:ffff:ffff
2062e22:cd0::/282e22:cdf:ffff:ffff:ffff:ffff:ffff:ffff
2072e22:ce0::/282e22:cef:ffff:ffff:ffff:ffff:ffff:ffff
2082e22:cf0::/282e22:cff:ffff:ffff:ffff:ffff:ffff:ffff
2092e22:d00::/282e22:d0f:ffff:ffff:ffff:ffff:ffff:ffff
2102e22:d10::/282e22:d1f:ffff:ffff:ffff:ffff:ffff:ffff
2112e22:d20::/282e22:d2f:ffff:ffff:ffff:ffff:ffff:ffff
2122e22:d30::/282e22:d3f:ffff:ffff:ffff:ffff:ffff:ffff
2132e22:d40::/282e22:d4f:ffff:ffff:ffff:ffff:ffff:ffff
2142e22:d50::/282e22:d5f:ffff:ffff:ffff:ffff:ffff:ffff
2152e22:d60::/282e22:d6f:ffff:ffff:ffff:ffff:ffff:ffff
2162e22:d70::/282e22:d7f:ffff:ffff:ffff:ffff:ffff:ffff
2172e22:d80::/282e22:d8f:ffff:ffff:ffff:ffff:ffff:ffff
2182e22:d90::/282e22:d9f:ffff:ffff:ffff:ffff:ffff:ffff
2192e22:da0::/282e22:daf:ffff:ffff:ffff:ffff:ffff:ffff
2202e22:db0::/282e22:dbf:ffff:ffff:ffff:ffff:ffff:ffff
2212e22:dc0::/282e22:dcf:ffff:ffff:ffff:ffff:ffff:ffff
2222e22:dd0::/282e22:ddf:ffff:ffff:ffff:ffff:ffff:ffff
2232e22:de0::/282e22:def:ffff:ffff:ffff:ffff:ffff:ffff
2242e22:df0::/282e22:dff:ffff:ffff:ffff:ffff:ffff:ffff
2252e22:e00::/282e22:e0f:ffff:ffff:ffff:ffff:ffff:ffff
2262e22:e10::/282e22:e1f:ffff:ffff:ffff:ffff:ffff:ffff
2272e22:e20::/282e22:e2f:ffff:ffff:ffff:ffff:ffff:ffff
2282e22:e30::/282e22:e3f:ffff:ffff:ffff:ffff:ffff:ffff
2292e22:e40::/282e22:e4f:ffff:ffff:ffff:ffff:ffff:ffff
2302e22:e50::/282e22:e5f:ffff:ffff:ffff:ffff:ffff:ffff
2312e22:e60::/282e22:e6f:ffff:ffff:ffff:ffff:ffff:ffff
2322e22:e70::/282e22:e7f:ffff:ffff:ffff:ffff:ffff:ffff
2332e22:e80::/282e22:e8f:ffff:ffff:ffff:ffff:ffff:ffff
2342e22:e90::/282e22:e9f:ffff:ffff:ffff:ffff:ffff:ffff
2352e22:ea0::/282e22:eaf:ffff:ffff:ffff:ffff:ffff:ffff
2362e22:eb0::/282e22:ebf:ffff:ffff:ffff:ffff:ffff:ffff
2372e22:ec0::/282e22:ecf:ffff:ffff:ffff:ffff:ffff:ffff
2382e22:ed0::/282e22:edf:ffff:ffff:ffff:ffff:ffff:ffff
2392e22:ee0::/282e22:eef:ffff:ffff:ffff:ffff:ffff:ffff
2402e22:ef0::/282e22:eff:ffff:ffff:ffff:ffff:ffff:ffff
2412e22:f00::/282e22:f0f:ffff:ffff:ffff:ffff:ffff:ffff
2422e22:f10::/282e22:f1f:ffff:ffff:ffff:ffff:ffff:ffff
2432e22:f20::/282e22:f2f:ffff:ffff:ffff:ffff:ffff:ffff
2442e22:f30::/282e22:f3f:ffff:ffff:ffff:ffff:ffff:ffff
2452e22:f40::/282e22:f4f:ffff:ffff:ffff:ffff:ffff:ffff
2462e22:f50::/282e22:f5f:ffff:ffff:ffff:ffff:ffff:ffff
2472e22:f60::/282e22:f6f:ffff:ffff:ffff:ffff:ffff:ffff
2482e22:f70::/282e22:f7f:ffff:ffff:ffff:ffff:ffff:ffff
2492e22:f80::/282e22:f8f:ffff:ffff:ffff:ffff:ffff:ffff
2502e22:f90::/282e22:f9f:ffff:ffff:ffff:ffff:ffff:ffff
2512e22:fa0::/282e22:faf:ffff:ffff:ffff:ffff:ffff:ffff
2522e22:fb0::/282e22:fbf:ffff:ffff:ffff:ffff:ffff:ffff
2532e22:fc0::/282e22:fcf:ffff:ffff:ffff:ffff:ffff:ffff
2542e22:fd0::/282e22:fdf:ffff:ffff:ffff:ffff:ffff:ffff
2552e22:fe0::/282e22:fef:ffff:ffff:ffff:ffff:ffff:ffff
2562e22:ff0::/282e22: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.