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

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

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