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

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

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