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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
2650::/12
First address
2650::
Last address
265f: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
2650:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
5.6.2.ip6.arpa
Split into smaller subnets/28
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2650::/12 makes 65,536 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
12650::/282650:f:ffff:ffff:ffff:ffff:ffff:ffff
22650:10::/282650:1f:ffff:ffff:ffff:ffff:ffff:ffff
32650:20::/282650:2f:ffff:ffff:ffff:ffff:ffff:ffff
42650:30::/282650:3f:ffff:ffff:ffff:ffff:ffff:ffff
52650:40::/282650:4f:ffff:ffff:ffff:ffff:ffff:ffff
62650:50::/282650:5f:ffff:ffff:ffff:ffff:ffff:ffff
72650:60::/282650:6f:ffff:ffff:ffff:ffff:ffff:ffff
82650:70::/282650:7f:ffff:ffff:ffff:ffff:ffff:ffff
92650:80::/282650:8f:ffff:ffff:ffff:ffff:ffff:ffff
102650:90::/282650:9f:ffff:ffff:ffff:ffff:ffff:ffff
112650:a0::/282650:af:ffff:ffff:ffff:ffff:ffff:ffff
122650:b0::/282650:bf:ffff:ffff:ffff:ffff:ffff:ffff
132650:c0::/282650:cf:ffff:ffff:ffff:ffff:ffff:ffff
142650:d0::/282650:df:ffff:ffff:ffff:ffff:ffff:ffff
152650:e0::/282650:ef:ffff:ffff:ffff:ffff:ffff:ffff
162650:f0::/282650:ff:ffff:ffff:ffff:ffff:ffff:ffff
172650:100::/282650:10f:ffff:ffff:ffff:ffff:ffff:ffff
182650:110::/282650:11f:ffff:ffff:ffff:ffff:ffff:ffff
192650:120::/282650:12f:ffff:ffff:ffff:ffff:ffff:ffff
202650:130::/282650:13f:ffff:ffff:ffff:ffff:ffff:ffff
212650:140::/282650:14f:ffff:ffff:ffff:ffff:ffff:ffff
222650:150::/282650:15f:ffff:ffff:ffff:ffff:ffff:ffff
232650:160::/282650:16f:ffff:ffff:ffff:ffff:ffff:ffff
242650:170::/282650:17f:ffff:ffff:ffff:ffff:ffff:ffff
252650:180::/282650:18f:ffff:ffff:ffff:ffff:ffff:ffff
262650:190::/282650:19f:ffff:ffff:ffff:ffff:ffff:ffff
272650:1a0::/282650:1af:ffff:ffff:ffff:ffff:ffff:ffff
282650:1b0::/282650:1bf:ffff:ffff:ffff:ffff:ffff:ffff
292650:1c0::/282650:1cf:ffff:ffff:ffff:ffff:ffff:ffff
302650:1d0::/282650:1df:ffff:ffff:ffff:ffff:ffff:ffff
312650:1e0::/282650:1ef:ffff:ffff:ffff:ffff:ffff:ffff
322650:1f0::/282650:1ff:ffff:ffff:ffff:ffff:ffff:ffff
332650:200::/282650:20f:ffff:ffff:ffff:ffff:ffff:ffff
342650:210::/282650:21f:ffff:ffff:ffff:ffff:ffff:ffff
352650:220::/282650:22f:ffff:ffff:ffff:ffff:ffff:ffff
362650:230::/282650:23f:ffff:ffff:ffff:ffff:ffff:ffff
372650:240::/282650:24f:ffff:ffff:ffff:ffff:ffff:ffff
382650:250::/282650:25f:ffff:ffff:ffff:ffff:ffff:ffff
392650:260::/282650:26f:ffff:ffff:ffff:ffff:ffff:ffff
402650:270::/282650:27f:ffff:ffff:ffff:ffff:ffff:ffff
412650:280::/282650:28f:ffff:ffff:ffff:ffff:ffff:ffff
422650:290::/282650:29f:ffff:ffff:ffff:ffff:ffff:ffff
432650:2a0::/282650:2af:ffff:ffff:ffff:ffff:ffff:ffff
442650:2b0::/282650:2bf:ffff:ffff:ffff:ffff:ffff:ffff
452650:2c0::/282650:2cf:ffff:ffff:ffff:ffff:ffff:ffff
462650:2d0::/282650:2df:ffff:ffff:ffff:ffff:ffff:ffff
472650:2e0::/282650:2ef:ffff:ffff:ffff:ffff:ffff:ffff
482650:2f0::/282650:2ff:ffff:ffff:ffff:ffff:ffff:ffff
492650:300::/282650:30f:ffff:ffff:ffff:ffff:ffff:ffff
502650:310::/282650:31f:ffff:ffff:ffff:ffff:ffff:ffff
512650:320::/282650:32f:ffff:ffff:ffff:ffff:ffff:ffff
522650:330::/282650:33f:ffff:ffff:ffff:ffff:ffff:ffff
532650:340::/282650:34f:ffff:ffff:ffff:ffff:ffff:ffff
542650:350::/282650:35f:ffff:ffff:ffff:ffff:ffff:ffff
552650:360::/282650:36f:ffff:ffff:ffff:ffff:ffff:ffff
562650:370::/282650:37f:ffff:ffff:ffff:ffff:ffff:ffff
572650:380::/282650:38f:ffff:ffff:ffff:ffff:ffff:ffff
582650:390::/282650:39f:ffff:ffff:ffff:ffff:ffff:ffff
592650:3a0::/282650:3af:ffff:ffff:ffff:ffff:ffff:ffff
602650:3b0::/282650:3bf:ffff:ffff:ffff:ffff:ffff:ffff
612650:3c0::/282650:3cf:ffff:ffff:ffff:ffff:ffff:ffff
622650:3d0::/282650:3df:ffff:ffff:ffff:ffff:ffff:ffff
632650:3e0::/282650:3ef:ffff:ffff:ffff:ffff:ffff:ffff
642650:3f0::/282650:3ff:ffff:ffff:ffff:ffff:ffff:ffff
652650:400::/282650:40f:ffff:ffff:ffff:ffff:ffff:ffff
662650:410::/282650:41f:ffff:ffff:ffff:ffff:ffff:ffff
672650:420::/282650:42f:ffff:ffff:ffff:ffff:ffff:ffff
682650:430::/282650:43f:ffff:ffff:ffff:ffff:ffff:ffff
692650:440::/282650:44f:ffff:ffff:ffff:ffff:ffff:ffff
702650:450::/282650:45f:ffff:ffff:ffff:ffff:ffff:ffff
712650:460::/282650:46f:ffff:ffff:ffff:ffff:ffff:ffff
722650:470::/282650:47f:ffff:ffff:ffff:ffff:ffff:ffff
732650:480::/282650:48f:ffff:ffff:ffff:ffff:ffff:ffff
742650:490::/282650:49f:ffff:ffff:ffff:ffff:ffff:ffff
752650:4a0::/282650:4af:ffff:ffff:ffff:ffff:ffff:ffff
762650:4b0::/282650:4bf:ffff:ffff:ffff:ffff:ffff:ffff
772650:4c0::/282650:4cf:ffff:ffff:ffff:ffff:ffff:ffff
782650:4d0::/282650:4df:ffff:ffff:ffff:ffff:ffff:ffff
792650:4e0::/282650:4ef:ffff:ffff:ffff:ffff:ffff:ffff
802650:4f0::/282650:4ff:ffff:ffff:ffff:ffff:ffff:ffff
812650:500::/282650:50f:ffff:ffff:ffff:ffff:ffff:ffff
822650:510::/282650:51f:ffff:ffff:ffff:ffff:ffff:ffff
832650:520::/282650:52f:ffff:ffff:ffff:ffff:ffff:ffff
842650:530::/282650:53f:ffff:ffff:ffff:ffff:ffff:ffff
852650:540::/282650:54f:ffff:ffff:ffff:ffff:ffff:ffff
862650:550::/282650:55f:ffff:ffff:ffff:ffff:ffff:ffff
872650:560::/282650:56f:ffff:ffff:ffff:ffff:ffff:ffff
882650:570::/282650:57f:ffff:ffff:ffff:ffff:ffff:ffff
892650:580::/282650:58f:ffff:ffff:ffff:ffff:ffff:ffff
902650:590::/282650:59f:ffff:ffff:ffff:ffff:ffff:ffff
912650:5a0::/282650:5af:ffff:ffff:ffff:ffff:ffff:ffff
922650:5b0::/282650:5bf:ffff:ffff:ffff:ffff:ffff:ffff
932650:5c0::/282650:5cf:ffff:ffff:ffff:ffff:ffff:ffff
942650:5d0::/282650:5df:ffff:ffff:ffff:ffff:ffff:ffff
952650:5e0::/282650:5ef:ffff:ffff:ffff:ffff:ffff:ffff
962650:5f0::/282650:5ff:ffff:ffff:ffff:ffff:ffff:ffff
972650:600::/282650:60f:ffff:ffff:ffff:ffff:ffff:ffff
982650:610::/282650:61f:ffff:ffff:ffff:ffff:ffff:ffff
992650:620::/282650:62f:ffff:ffff:ffff:ffff:ffff:ffff
1002650:630::/282650:63f:ffff:ffff:ffff:ffff:ffff:ffff
1012650:640::/282650:64f:ffff:ffff:ffff:ffff:ffff:ffff
1022650:650::/282650:65f:ffff:ffff:ffff:ffff:ffff:ffff
1032650:660::/282650:66f:ffff:ffff:ffff:ffff:ffff:ffff
1042650:670::/282650:67f:ffff:ffff:ffff:ffff:ffff:ffff
1052650:680::/282650:68f:ffff:ffff:ffff:ffff:ffff:ffff
1062650:690::/282650:69f:ffff:ffff:ffff:ffff:ffff:ffff
1072650:6a0::/282650:6af:ffff:ffff:ffff:ffff:ffff:ffff
1082650:6b0::/282650:6bf:ffff:ffff:ffff:ffff:ffff:ffff
1092650:6c0::/282650:6cf:ffff:ffff:ffff:ffff:ffff:ffff
1102650:6d0::/282650:6df:ffff:ffff:ffff:ffff:ffff:ffff
1112650:6e0::/282650:6ef:ffff:ffff:ffff:ffff:ffff:ffff
1122650:6f0::/282650:6ff:ffff:ffff:ffff:ffff:ffff:ffff
1132650:700::/282650:70f:ffff:ffff:ffff:ffff:ffff:ffff
1142650:710::/282650:71f:ffff:ffff:ffff:ffff:ffff:ffff
1152650:720::/282650:72f:ffff:ffff:ffff:ffff:ffff:ffff
1162650:730::/282650:73f:ffff:ffff:ffff:ffff:ffff:ffff
1172650:740::/282650:74f:ffff:ffff:ffff:ffff:ffff:ffff
1182650:750::/282650:75f:ffff:ffff:ffff:ffff:ffff:ffff
1192650:760::/282650:76f:ffff:ffff:ffff:ffff:ffff:ffff
1202650:770::/282650:77f:ffff:ffff:ffff:ffff:ffff:ffff
1212650:780::/282650:78f:ffff:ffff:ffff:ffff:ffff:ffff
1222650:790::/282650:79f:ffff:ffff:ffff:ffff:ffff:ffff
1232650:7a0::/282650:7af:ffff:ffff:ffff:ffff:ffff:ffff
1242650:7b0::/282650:7bf:ffff:ffff:ffff:ffff:ffff:ffff
1252650:7c0::/282650:7cf:ffff:ffff:ffff:ffff:ffff:ffff
1262650:7d0::/282650:7df:ffff:ffff:ffff:ffff:ffff:ffff
1272650:7e0::/282650:7ef:ffff:ffff:ffff:ffff:ffff:ffff
1282650:7f0::/282650:7ff:ffff:ffff:ffff:ffff:ffff:ffff
1292650:800::/282650:80f:ffff:ffff:ffff:ffff:ffff:ffff
1302650:810::/282650:81f:ffff:ffff:ffff:ffff:ffff:ffff
1312650:820::/282650:82f:ffff:ffff:ffff:ffff:ffff:ffff
1322650:830::/282650:83f:ffff:ffff:ffff:ffff:ffff:ffff
1332650:840::/282650:84f:ffff:ffff:ffff:ffff:ffff:ffff
1342650:850::/282650:85f:ffff:ffff:ffff:ffff:ffff:ffff
1352650:860::/282650:86f:ffff:ffff:ffff:ffff:ffff:ffff
1362650:870::/282650:87f:ffff:ffff:ffff:ffff:ffff:ffff
1372650:880::/282650:88f:ffff:ffff:ffff:ffff:ffff:ffff
1382650:890::/282650:89f:ffff:ffff:ffff:ffff:ffff:ffff
1392650:8a0::/282650:8af:ffff:ffff:ffff:ffff:ffff:ffff
1402650:8b0::/282650:8bf:ffff:ffff:ffff:ffff:ffff:ffff
1412650:8c0::/282650:8cf:ffff:ffff:ffff:ffff:ffff:ffff
1422650:8d0::/282650:8df:ffff:ffff:ffff:ffff:ffff:ffff
1432650:8e0::/282650:8ef:ffff:ffff:ffff:ffff:ffff:ffff
1442650:8f0::/282650:8ff:ffff:ffff:ffff:ffff:ffff:ffff
1452650:900::/282650:90f:ffff:ffff:ffff:ffff:ffff:ffff
1462650:910::/282650:91f:ffff:ffff:ffff:ffff:ffff:ffff
1472650:920::/282650:92f:ffff:ffff:ffff:ffff:ffff:ffff
1482650:930::/282650:93f:ffff:ffff:ffff:ffff:ffff:ffff
1492650:940::/282650:94f:ffff:ffff:ffff:ffff:ffff:ffff
1502650:950::/282650:95f:ffff:ffff:ffff:ffff:ffff:ffff
1512650:960::/282650:96f:ffff:ffff:ffff:ffff:ffff:ffff
1522650:970::/282650:97f:ffff:ffff:ffff:ffff:ffff:ffff
1532650:980::/282650:98f:ffff:ffff:ffff:ffff:ffff:ffff
1542650:990::/282650:99f:ffff:ffff:ffff:ffff:ffff:ffff
1552650:9a0::/282650:9af:ffff:ffff:ffff:ffff:ffff:ffff
1562650:9b0::/282650:9bf:ffff:ffff:ffff:ffff:ffff:ffff
1572650:9c0::/282650:9cf:ffff:ffff:ffff:ffff:ffff:ffff
1582650:9d0::/282650:9df:ffff:ffff:ffff:ffff:ffff:ffff
1592650:9e0::/282650:9ef:ffff:ffff:ffff:ffff:ffff:ffff
1602650:9f0::/282650:9ff:ffff:ffff:ffff:ffff:ffff:ffff
1612650:a00::/282650:a0f:ffff:ffff:ffff:ffff:ffff:ffff
1622650:a10::/282650:a1f:ffff:ffff:ffff:ffff:ffff:ffff
1632650:a20::/282650:a2f:ffff:ffff:ffff:ffff:ffff:ffff
1642650:a30::/282650:a3f:ffff:ffff:ffff:ffff:ffff:ffff
1652650:a40::/282650:a4f:ffff:ffff:ffff:ffff:ffff:ffff
1662650:a50::/282650:a5f:ffff:ffff:ffff:ffff:ffff:ffff
1672650:a60::/282650:a6f:ffff:ffff:ffff:ffff:ffff:ffff
1682650:a70::/282650:a7f:ffff:ffff:ffff:ffff:ffff:ffff
1692650:a80::/282650:a8f:ffff:ffff:ffff:ffff:ffff:ffff
1702650:a90::/282650:a9f:ffff:ffff:ffff:ffff:ffff:ffff
1712650:aa0::/282650:aaf:ffff:ffff:ffff:ffff:ffff:ffff
1722650:ab0::/282650:abf:ffff:ffff:ffff:ffff:ffff:ffff
1732650:ac0::/282650:acf:ffff:ffff:ffff:ffff:ffff:ffff
1742650:ad0::/282650:adf:ffff:ffff:ffff:ffff:ffff:ffff
1752650:ae0::/282650:aef:ffff:ffff:ffff:ffff:ffff:ffff
1762650:af0::/282650:aff:ffff:ffff:ffff:ffff:ffff:ffff
1772650:b00::/282650:b0f:ffff:ffff:ffff:ffff:ffff:ffff
1782650:b10::/282650:b1f:ffff:ffff:ffff:ffff:ffff:ffff
1792650:b20::/282650:b2f:ffff:ffff:ffff:ffff:ffff:ffff
1802650:b30::/282650:b3f:ffff:ffff:ffff:ffff:ffff:ffff
1812650:b40::/282650:b4f:ffff:ffff:ffff:ffff:ffff:ffff
1822650:b50::/282650:b5f:ffff:ffff:ffff:ffff:ffff:ffff
1832650:b60::/282650:b6f:ffff:ffff:ffff:ffff:ffff:ffff
1842650:b70::/282650:b7f:ffff:ffff:ffff:ffff:ffff:ffff
1852650:b80::/282650:b8f:ffff:ffff:ffff:ffff:ffff:ffff
1862650:b90::/282650:b9f:ffff:ffff:ffff:ffff:ffff:ffff
1872650:ba0::/282650:baf:ffff:ffff:ffff:ffff:ffff:ffff
1882650:bb0::/282650:bbf:ffff:ffff:ffff:ffff:ffff:ffff
1892650:bc0::/282650:bcf:ffff:ffff:ffff:ffff:ffff:ffff
1902650:bd0::/282650:bdf:ffff:ffff:ffff:ffff:ffff:ffff
1912650:be0::/282650:bef:ffff:ffff:ffff:ffff:ffff:ffff
1922650:bf0::/282650:bff:ffff:ffff:ffff:ffff:ffff:ffff
1932650:c00::/282650:c0f:ffff:ffff:ffff:ffff:ffff:ffff
1942650:c10::/282650:c1f:ffff:ffff:ffff:ffff:ffff:ffff
1952650:c20::/282650:c2f:ffff:ffff:ffff:ffff:ffff:ffff
1962650:c30::/282650:c3f:ffff:ffff:ffff:ffff:ffff:ffff
1972650:c40::/282650:c4f:ffff:ffff:ffff:ffff:ffff:ffff
1982650:c50::/282650:c5f:ffff:ffff:ffff:ffff:ffff:ffff
1992650:c60::/282650:c6f:ffff:ffff:ffff:ffff:ffff:ffff
2002650:c70::/282650:c7f:ffff:ffff:ffff:ffff:ffff:ffff
2012650:c80::/282650:c8f:ffff:ffff:ffff:ffff:ffff:ffff
2022650:c90::/282650:c9f:ffff:ffff:ffff:ffff:ffff:ffff
2032650:ca0::/282650:caf:ffff:ffff:ffff:ffff:ffff:ffff
2042650:cb0::/282650:cbf:ffff:ffff:ffff:ffff:ffff:ffff
2052650:cc0::/282650:ccf:ffff:ffff:ffff:ffff:ffff:ffff
2062650:cd0::/282650:cdf:ffff:ffff:ffff:ffff:ffff:ffff
2072650:ce0::/282650:cef:ffff:ffff:ffff:ffff:ffff:ffff
2082650:cf0::/282650:cff:ffff:ffff:ffff:ffff:ffff:ffff
2092650:d00::/282650:d0f:ffff:ffff:ffff:ffff:ffff:ffff
2102650:d10::/282650:d1f:ffff:ffff:ffff:ffff:ffff:ffff
2112650:d20::/282650:d2f:ffff:ffff:ffff:ffff:ffff:ffff
2122650:d30::/282650:d3f:ffff:ffff:ffff:ffff:ffff:ffff
2132650:d40::/282650:d4f:ffff:ffff:ffff:ffff:ffff:ffff
2142650:d50::/282650:d5f:ffff:ffff:ffff:ffff:ffff:ffff
2152650:d60::/282650:d6f:ffff:ffff:ffff:ffff:ffff:ffff
2162650:d70::/282650:d7f:ffff:ffff:ffff:ffff:ffff:ffff
2172650:d80::/282650:d8f:ffff:ffff:ffff:ffff:ffff:ffff
2182650:d90::/282650:d9f:ffff:ffff:ffff:ffff:ffff:ffff
2192650:da0::/282650:daf:ffff:ffff:ffff:ffff:ffff:ffff
2202650:db0::/282650:dbf:ffff:ffff:ffff:ffff:ffff:ffff
2212650:dc0::/282650:dcf:ffff:ffff:ffff:ffff:ffff:ffff
2222650:dd0::/282650:ddf:ffff:ffff:ffff:ffff:ffff:ffff
2232650:de0::/282650:def:ffff:ffff:ffff:ffff:ffff:ffff
2242650:df0::/282650:dff:ffff:ffff:ffff:ffff:ffff:ffff
2252650:e00::/282650:e0f:ffff:ffff:ffff:ffff:ffff:ffff
2262650:e10::/282650:e1f:ffff:ffff:ffff:ffff:ffff:ffff
2272650:e20::/282650:e2f:ffff:ffff:ffff:ffff:ffff:ffff
2282650:e30::/282650:e3f:ffff:ffff:ffff:ffff:ffff:ffff
2292650:e40::/282650:e4f:ffff:ffff:ffff:ffff:ffff:ffff
2302650:e50::/282650:e5f:ffff:ffff:ffff:ffff:ffff:ffff
2312650:e60::/282650:e6f:ffff:ffff:ffff:ffff:ffff:ffff
2322650:e70::/282650:e7f:ffff:ffff:ffff:ffff:ffff:ffff
2332650:e80::/282650:e8f:ffff:ffff:ffff:ffff:ffff:ffff
2342650:e90::/282650:e9f:ffff:ffff:ffff:ffff:ffff:ffff
2352650:ea0::/282650:eaf:ffff:ffff:ffff:ffff:ffff:ffff
2362650:eb0::/282650:ebf:ffff:ffff:ffff:ffff:ffff:ffff
2372650:ec0::/282650:ecf:ffff:ffff:ffff:ffff:ffff:ffff
2382650:ed0::/282650:edf:ffff:ffff:ffff:ffff:ffff:ffff
2392650:ee0::/282650:eef:ffff:ffff:ffff:ffff:ffff:ffff
2402650:ef0::/282650:eff:ffff:ffff:ffff:ffff:ffff:ffff
2412650:f00::/282650:f0f:ffff:ffff:ffff:ffff:ffff:ffff
2422650:f10::/282650:f1f:ffff:ffff:ffff:ffff:ffff:ffff
2432650:f20::/282650:f2f:ffff:ffff:ffff:ffff:ffff:ffff
2442650:f30::/282650:f3f:ffff:ffff:ffff:ffff:ffff:ffff
2452650:f40::/282650:f4f:ffff:ffff:ffff:ffff:ffff:ffff
2462650:f50::/282650:f5f:ffff:ffff:ffff:ffff:ffff:ffff
2472650:f60::/282650:f6f:ffff:ffff:ffff:ffff:ffff:ffff
2482650:f70::/282650:f7f:ffff:ffff:ffff:ffff:ffff:ffff
2492650:f80::/282650:f8f:ffff:ffff:ffff:ffff:ffff:ffff
2502650:f90::/282650:f9f:ffff:ffff:ffff:ffff:ffff:ffff
2512650:fa0::/282650:faf:ffff:ffff:ffff:ffff:ffff:ffff
2522650:fb0::/282650:fbf:ffff:ffff:ffff:ffff:ffff:ffff
2532650:fc0::/282650:fcf:ffff:ffff:ffff:ffff:ffff:ffff
2542650:fd0::/282650:fdf:ffff:ffff:ffff:ffff:ffff:ffff
2552650:fe0::/282650:fef:ffff:ffff:ffff:ffff:ffff:ffff
2562650:ff0::/282650: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.