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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
2630::/12
First address
2630::
Last address
263f: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
2630:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.6.2.ip6.arpa
Split into smaller subnets/28
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2630::/12 makes 65,536 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
12630::/282630:f:ffff:ffff:ffff:ffff:ffff:ffff
22630:10::/282630:1f:ffff:ffff:ffff:ffff:ffff:ffff
32630:20::/282630:2f:ffff:ffff:ffff:ffff:ffff:ffff
42630:30::/282630:3f:ffff:ffff:ffff:ffff:ffff:ffff
52630:40::/282630:4f:ffff:ffff:ffff:ffff:ffff:ffff
62630:50::/282630:5f:ffff:ffff:ffff:ffff:ffff:ffff
72630:60::/282630:6f:ffff:ffff:ffff:ffff:ffff:ffff
82630:70::/282630:7f:ffff:ffff:ffff:ffff:ffff:ffff
92630:80::/282630:8f:ffff:ffff:ffff:ffff:ffff:ffff
102630:90::/282630:9f:ffff:ffff:ffff:ffff:ffff:ffff
112630:a0::/282630:af:ffff:ffff:ffff:ffff:ffff:ffff
122630:b0::/282630:bf:ffff:ffff:ffff:ffff:ffff:ffff
132630:c0::/282630:cf:ffff:ffff:ffff:ffff:ffff:ffff
142630:d0::/282630:df:ffff:ffff:ffff:ffff:ffff:ffff
152630:e0::/282630:ef:ffff:ffff:ffff:ffff:ffff:ffff
162630:f0::/282630:ff:ffff:ffff:ffff:ffff:ffff:ffff
172630:100::/282630:10f:ffff:ffff:ffff:ffff:ffff:ffff
182630:110::/282630:11f:ffff:ffff:ffff:ffff:ffff:ffff
192630:120::/282630:12f:ffff:ffff:ffff:ffff:ffff:ffff
202630:130::/282630:13f:ffff:ffff:ffff:ffff:ffff:ffff
212630:140::/282630:14f:ffff:ffff:ffff:ffff:ffff:ffff
222630:150::/282630:15f:ffff:ffff:ffff:ffff:ffff:ffff
232630:160::/282630:16f:ffff:ffff:ffff:ffff:ffff:ffff
242630:170::/282630:17f:ffff:ffff:ffff:ffff:ffff:ffff
252630:180::/282630:18f:ffff:ffff:ffff:ffff:ffff:ffff
262630:190::/282630:19f:ffff:ffff:ffff:ffff:ffff:ffff
272630:1a0::/282630:1af:ffff:ffff:ffff:ffff:ffff:ffff
282630:1b0::/282630:1bf:ffff:ffff:ffff:ffff:ffff:ffff
292630:1c0::/282630:1cf:ffff:ffff:ffff:ffff:ffff:ffff
302630:1d0::/282630:1df:ffff:ffff:ffff:ffff:ffff:ffff
312630:1e0::/282630:1ef:ffff:ffff:ffff:ffff:ffff:ffff
322630:1f0::/282630:1ff:ffff:ffff:ffff:ffff:ffff:ffff
332630:200::/282630:20f:ffff:ffff:ffff:ffff:ffff:ffff
342630:210::/282630:21f:ffff:ffff:ffff:ffff:ffff:ffff
352630:220::/282630:22f:ffff:ffff:ffff:ffff:ffff:ffff
362630:230::/282630:23f:ffff:ffff:ffff:ffff:ffff:ffff
372630:240::/282630:24f:ffff:ffff:ffff:ffff:ffff:ffff
382630:250::/282630:25f:ffff:ffff:ffff:ffff:ffff:ffff
392630:260::/282630:26f:ffff:ffff:ffff:ffff:ffff:ffff
402630:270::/282630:27f:ffff:ffff:ffff:ffff:ffff:ffff
412630:280::/282630:28f:ffff:ffff:ffff:ffff:ffff:ffff
422630:290::/282630:29f:ffff:ffff:ffff:ffff:ffff:ffff
432630:2a0::/282630:2af:ffff:ffff:ffff:ffff:ffff:ffff
442630:2b0::/282630:2bf:ffff:ffff:ffff:ffff:ffff:ffff
452630:2c0::/282630:2cf:ffff:ffff:ffff:ffff:ffff:ffff
462630:2d0::/282630:2df:ffff:ffff:ffff:ffff:ffff:ffff
472630:2e0::/282630:2ef:ffff:ffff:ffff:ffff:ffff:ffff
482630:2f0::/282630:2ff:ffff:ffff:ffff:ffff:ffff:ffff
492630:300::/282630:30f:ffff:ffff:ffff:ffff:ffff:ffff
502630:310::/282630:31f:ffff:ffff:ffff:ffff:ffff:ffff
512630:320::/282630:32f:ffff:ffff:ffff:ffff:ffff:ffff
522630:330::/282630:33f:ffff:ffff:ffff:ffff:ffff:ffff
532630:340::/282630:34f:ffff:ffff:ffff:ffff:ffff:ffff
542630:350::/282630:35f:ffff:ffff:ffff:ffff:ffff:ffff
552630:360::/282630:36f:ffff:ffff:ffff:ffff:ffff:ffff
562630:370::/282630:37f:ffff:ffff:ffff:ffff:ffff:ffff
572630:380::/282630:38f:ffff:ffff:ffff:ffff:ffff:ffff
582630:390::/282630:39f:ffff:ffff:ffff:ffff:ffff:ffff
592630:3a0::/282630:3af:ffff:ffff:ffff:ffff:ffff:ffff
602630:3b0::/282630:3bf:ffff:ffff:ffff:ffff:ffff:ffff
612630:3c0::/282630:3cf:ffff:ffff:ffff:ffff:ffff:ffff
622630:3d0::/282630:3df:ffff:ffff:ffff:ffff:ffff:ffff
632630:3e0::/282630:3ef:ffff:ffff:ffff:ffff:ffff:ffff
642630:3f0::/282630:3ff:ffff:ffff:ffff:ffff:ffff:ffff
652630:400::/282630:40f:ffff:ffff:ffff:ffff:ffff:ffff
662630:410::/282630:41f:ffff:ffff:ffff:ffff:ffff:ffff
672630:420::/282630:42f:ffff:ffff:ffff:ffff:ffff:ffff
682630:430::/282630:43f:ffff:ffff:ffff:ffff:ffff:ffff
692630:440::/282630:44f:ffff:ffff:ffff:ffff:ffff:ffff
702630:450::/282630:45f:ffff:ffff:ffff:ffff:ffff:ffff
712630:460::/282630:46f:ffff:ffff:ffff:ffff:ffff:ffff
722630:470::/282630:47f:ffff:ffff:ffff:ffff:ffff:ffff
732630:480::/282630:48f:ffff:ffff:ffff:ffff:ffff:ffff
742630:490::/282630:49f:ffff:ffff:ffff:ffff:ffff:ffff
752630:4a0::/282630:4af:ffff:ffff:ffff:ffff:ffff:ffff
762630:4b0::/282630:4bf:ffff:ffff:ffff:ffff:ffff:ffff
772630:4c0::/282630:4cf:ffff:ffff:ffff:ffff:ffff:ffff
782630:4d0::/282630:4df:ffff:ffff:ffff:ffff:ffff:ffff
792630:4e0::/282630:4ef:ffff:ffff:ffff:ffff:ffff:ffff
802630:4f0::/282630:4ff:ffff:ffff:ffff:ffff:ffff:ffff
812630:500::/282630:50f:ffff:ffff:ffff:ffff:ffff:ffff
822630:510::/282630:51f:ffff:ffff:ffff:ffff:ffff:ffff
832630:520::/282630:52f:ffff:ffff:ffff:ffff:ffff:ffff
842630:530::/282630:53f:ffff:ffff:ffff:ffff:ffff:ffff
852630:540::/282630:54f:ffff:ffff:ffff:ffff:ffff:ffff
862630:550::/282630:55f:ffff:ffff:ffff:ffff:ffff:ffff
872630:560::/282630:56f:ffff:ffff:ffff:ffff:ffff:ffff
882630:570::/282630:57f:ffff:ffff:ffff:ffff:ffff:ffff
892630:580::/282630:58f:ffff:ffff:ffff:ffff:ffff:ffff
902630:590::/282630:59f:ffff:ffff:ffff:ffff:ffff:ffff
912630:5a0::/282630:5af:ffff:ffff:ffff:ffff:ffff:ffff
922630:5b0::/282630:5bf:ffff:ffff:ffff:ffff:ffff:ffff
932630:5c0::/282630:5cf:ffff:ffff:ffff:ffff:ffff:ffff
942630:5d0::/282630:5df:ffff:ffff:ffff:ffff:ffff:ffff
952630:5e0::/282630:5ef:ffff:ffff:ffff:ffff:ffff:ffff
962630:5f0::/282630:5ff:ffff:ffff:ffff:ffff:ffff:ffff
972630:600::/282630:60f:ffff:ffff:ffff:ffff:ffff:ffff
982630:610::/282630:61f:ffff:ffff:ffff:ffff:ffff:ffff
992630:620::/282630:62f:ffff:ffff:ffff:ffff:ffff:ffff
1002630:630::/282630:63f:ffff:ffff:ffff:ffff:ffff:ffff
1012630:640::/282630:64f:ffff:ffff:ffff:ffff:ffff:ffff
1022630:650::/282630:65f:ffff:ffff:ffff:ffff:ffff:ffff
1032630:660::/282630:66f:ffff:ffff:ffff:ffff:ffff:ffff
1042630:670::/282630:67f:ffff:ffff:ffff:ffff:ffff:ffff
1052630:680::/282630:68f:ffff:ffff:ffff:ffff:ffff:ffff
1062630:690::/282630:69f:ffff:ffff:ffff:ffff:ffff:ffff
1072630:6a0::/282630:6af:ffff:ffff:ffff:ffff:ffff:ffff
1082630:6b0::/282630:6bf:ffff:ffff:ffff:ffff:ffff:ffff
1092630:6c0::/282630:6cf:ffff:ffff:ffff:ffff:ffff:ffff
1102630:6d0::/282630:6df:ffff:ffff:ffff:ffff:ffff:ffff
1112630:6e0::/282630:6ef:ffff:ffff:ffff:ffff:ffff:ffff
1122630:6f0::/282630:6ff:ffff:ffff:ffff:ffff:ffff:ffff
1132630:700::/282630:70f:ffff:ffff:ffff:ffff:ffff:ffff
1142630:710::/282630:71f:ffff:ffff:ffff:ffff:ffff:ffff
1152630:720::/282630:72f:ffff:ffff:ffff:ffff:ffff:ffff
1162630:730::/282630:73f:ffff:ffff:ffff:ffff:ffff:ffff
1172630:740::/282630:74f:ffff:ffff:ffff:ffff:ffff:ffff
1182630:750::/282630:75f:ffff:ffff:ffff:ffff:ffff:ffff
1192630:760::/282630:76f:ffff:ffff:ffff:ffff:ffff:ffff
1202630:770::/282630:77f:ffff:ffff:ffff:ffff:ffff:ffff
1212630:780::/282630:78f:ffff:ffff:ffff:ffff:ffff:ffff
1222630:790::/282630:79f:ffff:ffff:ffff:ffff:ffff:ffff
1232630:7a0::/282630:7af:ffff:ffff:ffff:ffff:ffff:ffff
1242630:7b0::/282630:7bf:ffff:ffff:ffff:ffff:ffff:ffff
1252630:7c0::/282630:7cf:ffff:ffff:ffff:ffff:ffff:ffff
1262630:7d0::/282630:7df:ffff:ffff:ffff:ffff:ffff:ffff
1272630:7e0::/282630:7ef:ffff:ffff:ffff:ffff:ffff:ffff
1282630:7f0::/282630:7ff:ffff:ffff:ffff:ffff:ffff:ffff
1292630:800::/282630:80f:ffff:ffff:ffff:ffff:ffff:ffff
1302630:810::/282630:81f:ffff:ffff:ffff:ffff:ffff:ffff
1312630:820::/282630:82f:ffff:ffff:ffff:ffff:ffff:ffff
1322630:830::/282630:83f:ffff:ffff:ffff:ffff:ffff:ffff
1332630:840::/282630:84f:ffff:ffff:ffff:ffff:ffff:ffff
1342630:850::/282630:85f:ffff:ffff:ffff:ffff:ffff:ffff
1352630:860::/282630:86f:ffff:ffff:ffff:ffff:ffff:ffff
1362630:870::/282630:87f:ffff:ffff:ffff:ffff:ffff:ffff
1372630:880::/282630:88f:ffff:ffff:ffff:ffff:ffff:ffff
1382630:890::/282630:89f:ffff:ffff:ffff:ffff:ffff:ffff
1392630:8a0::/282630:8af:ffff:ffff:ffff:ffff:ffff:ffff
1402630:8b0::/282630:8bf:ffff:ffff:ffff:ffff:ffff:ffff
1412630:8c0::/282630:8cf:ffff:ffff:ffff:ffff:ffff:ffff
1422630:8d0::/282630:8df:ffff:ffff:ffff:ffff:ffff:ffff
1432630:8e0::/282630:8ef:ffff:ffff:ffff:ffff:ffff:ffff
1442630:8f0::/282630:8ff:ffff:ffff:ffff:ffff:ffff:ffff
1452630:900::/282630:90f:ffff:ffff:ffff:ffff:ffff:ffff
1462630:910::/282630:91f:ffff:ffff:ffff:ffff:ffff:ffff
1472630:920::/282630:92f:ffff:ffff:ffff:ffff:ffff:ffff
1482630:930::/282630:93f:ffff:ffff:ffff:ffff:ffff:ffff
1492630:940::/282630:94f:ffff:ffff:ffff:ffff:ffff:ffff
1502630:950::/282630:95f:ffff:ffff:ffff:ffff:ffff:ffff
1512630:960::/282630:96f:ffff:ffff:ffff:ffff:ffff:ffff
1522630:970::/282630:97f:ffff:ffff:ffff:ffff:ffff:ffff
1532630:980::/282630:98f:ffff:ffff:ffff:ffff:ffff:ffff
1542630:990::/282630:99f:ffff:ffff:ffff:ffff:ffff:ffff
1552630:9a0::/282630:9af:ffff:ffff:ffff:ffff:ffff:ffff
1562630:9b0::/282630:9bf:ffff:ffff:ffff:ffff:ffff:ffff
1572630:9c0::/282630:9cf:ffff:ffff:ffff:ffff:ffff:ffff
1582630:9d0::/282630:9df:ffff:ffff:ffff:ffff:ffff:ffff
1592630:9e0::/282630:9ef:ffff:ffff:ffff:ffff:ffff:ffff
1602630:9f0::/282630:9ff:ffff:ffff:ffff:ffff:ffff:ffff
1612630:a00::/282630:a0f:ffff:ffff:ffff:ffff:ffff:ffff
1622630:a10::/282630:a1f:ffff:ffff:ffff:ffff:ffff:ffff
1632630:a20::/282630:a2f:ffff:ffff:ffff:ffff:ffff:ffff
1642630:a30::/282630:a3f:ffff:ffff:ffff:ffff:ffff:ffff
1652630:a40::/282630:a4f:ffff:ffff:ffff:ffff:ffff:ffff
1662630:a50::/282630:a5f:ffff:ffff:ffff:ffff:ffff:ffff
1672630:a60::/282630:a6f:ffff:ffff:ffff:ffff:ffff:ffff
1682630:a70::/282630:a7f:ffff:ffff:ffff:ffff:ffff:ffff
1692630:a80::/282630:a8f:ffff:ffff:ffff:ffff:ffff:ffff
1702630:a90::/282630:a9f:ffff:ffff:ffff:ffff:ffff:ffff
1712630:aa0::/282630:aaf:ffff:ffff:ffff:ffff:ffff:ffff
1722630:ab0::/282630:abf:ffff:ffff:ffff:ffff:ffff:ffff
1732630:ac0::/282630:acf:ffff:ffff:ffff:ffff:ffff:ffff
1742630:ad0::/282630:adf:ffff:ffff:ffff:ffff:ffff:ffff
1752630:ae0::/282630:aef:ffff:ffff:ffff:ffff:ffff:ffff
1762630:af0::/282630:aff:ffff:ffff:ffff:ffff:ffff:ffff
1772630:b00::/282630:b0f:ffff:ffff:ffff:ffff:ffff:ffff
1782630:b10::/282630:b1f:ffff:ffff:ffff:ffff:ffff:ffff
1792630:b20::/282630:b2f:ffff:ffff:ffff:ffff:ffff:ffff
1802630:b30::/282630:b3f:ffff:ffff:ffff:ffff:ffff:ffff
1812630:b40::/282630:b4f:ffff:ffff:ffff:ffff:ffff:ffff
1822630:b50::/282630:b5f:ffff:ffff:ffff:ffff:ffff:ffff
1832630:b60::/282630:b6f:ffff:ffff:ffff:ffff:ffff:ffff
1842630:b70::/282630:b7f:ffff:ffff:ffff:ffff:ffff:ffff
1852630:b80::/282630:b8f:ffff:ffff:ffff:ffff:ffff:ffff
1862630:b90::/282630:b9f:ffff:ffff:ffff:ffff:ffff:ffff
1872630:ba0::/282630:baf:ffff:ffff:ffff:ffff:ffff:ffff
1882630:bb0::/282630:bbf:ffff:ffff:ffff:ffff:ffff:ffff
1892630:bc0::/282630:bcf:ffff:ffff:ffff:ffff:ffff:ffff
1902630:bd0::/282630:bdf:ffff:ffff:ffff:ffff:ffff:ffff
1912630:be0::/282630:bef:ffff:ffff:ffff:ffff:ffff:ffff
1922630:bf0::/282630:bff:ffff:ffff:ffff:ffff:ffff:ffff
1932630:c00::/282630:c0f:ffff:ffff:ffff:ffff:ffff:ffff
1942630:c10::/282630:c1f:ffff:ffff:ffff:ffff:ffff:ffff
1952630:c20::/282630:c2f:ffff:ffff:ffff:ffff:ffff:ffff
1962630:c30::/282630:c3f:ffff:ffff:ffff:ffff:ffff:ffff
1972630:c40::/282630:c4f:ffff:ffff:ffff:ffff:ffff:ffff
1982630:c50::/282630:c5f:ffff:ffff:ffff:ffff:ffff:ffff
1992630:c60::/282630:c6f:ffff:ffff:ffff:ffff:ffff:ffff
2002630:c70::/282630:c7f:ffff:ffff:ffff:ffff:ffff:ffff
2012630:c80::/282630:c8f:ffff:ffff:ffff:ffff:ffff:ffff
2022630:c90::/282630:c9f:ffff:ffff:ffff:ffff:ffff:ffff
2032630:ca0::/282630:caf:ffff:ffff:ffff:ffff:ffff:ffff
2042630:cb0::/282630:cbf:ffff:ffff:ffff:ffff:ffff:ffff
2052630:cc0::/282630:ccf:ffff:ffff:ffff:ffff:ffff:ffff
2062630:cd0::/282630:cdf:ffff:ffff:ffff:ffff:ffff:ffff
2072630:ce0::/282630:cef:ffff:ffff:ffff:ffff:ffff:ffff
2082630:cf0::/282630:cff:ffff:ffff:ffff:ffff:ffff:ffff
2092630:d00::/282630:d0f:ffff:ffff:ffff:ffff:ffff:ffff
2102630:d10::/282630:d1f:ffff:ffff:ffff:ffff:ffff:ffff
2112630:d20::/282630:d2f:ffff:ffff:ffff:ffff:ffff:ffff
2122630:d30::/282630:d3f:ffff:ffff:ffff:ffff:ffff:ffff
2132630:d40::/282630:d4f:ffff:ffff:ffff:ffff:ffff:ffff
2142630:d50::/282630:d5f:ffff:ffff:ffff:ffff:ffff:ffff
2152630:d60::/282630:d6f:ffff:ffff:ffff:ffff:ffff:ffff
2162630:d70::/282630:d7f:ffff:ffff:ffff:ffff:ffff:ffff
2172630:d80::/282630:d8f:ffff:ffff:ffff:ffff:ffff:ffff
2182630:d90::/282630:d9f:ffff:ffff:ffff:ffff:ffff:ffff
2192630:da0::/282630:daf:ffff:ffff:ffff:ffff:ffff:ffff
2202630:db0::/282630:dbf:ffff:ffff:ffff:ffff:ffff:ffff
2212630:dc0::/282630:dcf:ffff:ffff:ffff:ffff:ffff:ffff
2222630:dd0::/282630:ddf:ffff:ffff:ffff:ffff:ffff:ffff
2232630:de0::/282630:def:ffff:ffff:ffff:ffff:ffff:ffff
2242630:df0::/282630:dff:ffff:ffff:ffff:ffff:ffff:ffff
2252630:e00::/282630:e0f:ffff:ffff:ffff:ffff:ffff:ffff
2262630:e10::/282630:e1f:ffff:ffff:ffff:ffff:ffff:ffff
2272630:e20::/282630:e2f:ffff:ffff:ffff:ffff:ffff:ffff
2282630:e30::/282630:e3f:ffff:ffff:ffff:ffff:ffff:ffff
2292630:e40::/282630:e4f:ffff:ffff:ffff:ffff:ffff:ffff
2302630:e50::/282630:e5f:ffff:ffff:ffff:ffff:ffff:ffff
2312630:e60::/282630:e6f:ffff:ffff:ffff:ffff:ffff:ffff
2322630:e70::/282630:e7f:ffff:ffff:ffff:ffff:ffff:ffff
2332630:e80::/282630:e8f:ffff:ffff:ffff:ffff:ffff:ffff
2342630:e90::/282630:e9f:ffff:ffff:ffff:ffff:ffff:ffff
2352630:ea0::/282630:eaf:ffff:ffff:ffff:ffff:ffff:ffff
2362630:eb0::/282630:ebf:ffff:ffff:ffff:ffff:ffff:ffff
2372630:ec0::/282630:ecf:ffff:ffff:ffff:ffff:ffff:ffff
2382630:ed0::/282630:edf:ffff:ffff:ffff:ffff:ffff:ffff
2392630:ee0::/282630:eef:ffff:ffff:ffff:ffff:ffff:ffff
2402630:ef0::/282630:eff:ffff:ffff:ffff:ffff:ffff:ffff
2412630:f00::/282630:f0f:ffff:ffff:ffff:ffff:ffff:ffff
2422630:f10::/282630:f1f:ffff:ffff:ffff:ffff:ffff:ffff
2432630:f20::/282630:f2f:ffff:ffff:ffff:ffff:ffff:ffff
2442630:f30::/282630:f3f:ffff:ffff:ffff:ffff:ffff:ffff
2452630:f40::/282630:f4f:ffff:ffff:ffff:ffff:ffff:ffff
2462630:f50::/282630:f5f:ffff:ffff:ffff:ffff:ffff:ffff
2472630:f60::/282630:f6f:ffff:ffff:ffff:ffff:ffff:ffff
2482630:f70::/282630:f7f:ffff:ffff:ffff:ffff:ffff:ffff
2492630:f80::/282630:f8f:ffff:ffff:ffff:ffff:ffff:ffff
2502630:f90::/282630:f9f:ffff:ffff:ffff:ffff:ffff:ffff
2512630:fa0::/282630:faf:ffff:ffff:ffff:ffff:ffff:ffff
2522630:fb0::/282630:fbf:ffff:ffff:ffff:ffff:ffff:ffff
2532630:fc0::/282630:fcf:ffff:ffff:ffff:ffff:ffff:ffff
2542630:fd0::/282630:fdf:ffff:ffff:ffff:ffff:ffff:ffff
2552630:fe0::/282630:fef:ffff:ffff:ffff:ffff:ffff:ffff
2562630:ff0::/282630: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.