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

3ebd::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
13ebd::/283ebd:f:ffff:ffff:ffff:ffff:ffff:ffff
23ebd:10::/283ebd:1f:ffff:ffff:ffff:ffff:ffff:ffff
33ebd:20::/283ebd:2f:ffff:ffff:ffff:ffff:ffff:ffff
43ebd:30::/283ebd:3f:ffff:ffff:ffff:ffff:ffff:ffff
53ebd:40::/283ebd:4f:ffff:ffff:ffff:ffff:ffff:ffff
63ebd:50::/283ebd:5f:ffff:ffff:ffff:ffff:ffff:ffff
73ebd:60::/283ebd:6f:ffff:ffff:ffff:ffff:ffff:ffff
83ebd:70::/283ebd:7f:ffff:ffff:ffff:ffff:ffff:ffff
93ebd:80::/283ebd:8f:ffff:ffff:ffff:ffff:ffff:ffff
103ebd:90::/283ebd:9f:ffff:ffff:ffff:ffff:ffff:ffff
113ebd:a0::/283ebd:af:ffff:ffff:ffff:ffff:ffff:ffff
123ebd:b0::/283ebd:bf:ffff:ffff:ffff:ffff:ffff:ffff
133ebd:c0::/283ebd:cf:ffff:ffff:ffff:ffff:ffff:ffff
143ebd:d0::/283ebd:df:ffff:ffff:ffff:ffff:ffff:ffff
153ebd:e0::/283ebd:ef:ffff:ffff:ffff:ffff:ffff:ffff
163ebd:f0::/283ebd:ff:ffff:ffff:ffff:ffff:ffff:ffff
173ebd:100::/283ebd:10f:ffff:ffff:ffff:ffff:ffff:ffff
183ebd:110::/283ebd:11f:ffff:ffff:ffff:ffff:ffff:ffff
193ebd:120::/283ebd:12f:ffff:ffff:ffff:ffff:ffff:ffff
203ebd:130::/283ebd:13f:ffff:ffff:ffff:ffff:ffff:ffff
213ebd:140::/283ebd:14f:ffff:ffff:ffff:ffff:ffff:ffff
223ebd:150::/283ebd:15f:ffff:ffff:ffff:ffff:ffff:ffff
233ebd:160::/283ebd:16f:ffff:ffff:ffff:ffff:ffff:ffff
243ebd:170::/283ebd:17f:ffff:ffff:ffff:ffff:ffff:ffff
253ebd:180::/283ebd:18f:ffff:ffff:ffff:ffff:ffff:ffff
263ebd:190::/283ebd:19f:ffff:ffff:ffff:ffff:ffff:ffff
273ebd:1a0::/283ebd:1af:ffff:ffff:ffff:ffff:ffff:ffff
283ebd:1b0::/283ebd:1bf:ffff:ffff:ffff:ffff:ffff:ffff
293ebd:1c0::/283ebd:1cf:ffff:ffff:ffff:ffff:ffff:ffff
303ebd:1d0::/283ebd:1df:ffff:ffff:ffff:ffff:ffff:ffff
313ebd:1e0::/283ebd:1ef:ffff:ffff:ffff:ffff:ffff:ffff
323ebd:1f0::/283ebd:1ff:ffff:ffff:ffff:ffff:ffff:ffff
333ebd:200::/283ebd:20f:ffff:ffff:ffff:ffff:ffff:ffff
343ebd:210::/283ebd:21f:ffff:ffff:ffff:ffff:ffff:ffff
353ebd:220::/283ebd:22f:ffff:ffff:ffff:ffff:ffff:ffff
363ebd:230::/283ebd:23f:ffff:ffff:ffff:ffff:ffff:ffff
373ebd:240::/283ebd:24f:ffff:ffff:ffff:ffff:ffff:ffff
383ebd:250::/283ebd:25f:ffff:ffff:ffff:ffff:ffff:ffff
393ebd:260::/283ebd:26f:ffff:ffff:ffff:ffff:ffff:ffff
403ebd:270::/283ebd:27f:ffff:ffff:ffff:ffff:ffff:ffff
413ebd:280::/283ebd:28f:ffff:ffff:ffff:ffff:ffff:ffff
423ebd:290::/283ebd:29f:ffff:ffff:ffff:ffff:ffff:ffff
433ebd:2a0::/283ebd:2af:ffff:ffff:ffff:ffff:ffff:ffff
443ebd:2b0::/283ebd:2bf:ffff:ffff:ffff:ffff:ffff:ffff
453ebd:2c0::/283ebd:2cf:ffff:ffff:ffff:ffff:ffff:ffff
463ebd:2d0::/283ebd:2df:ffff:ffff:ffff:ffff:ffff:ffff
473ebd:2e0::/283ebd:2ef:ffff:ffff:ffff:ffff:ffff:ffff
483ebd:2f0::/283ebd:2ff:ffff:ffff:ffff:ffff:ffff:ffff
493ebd:300::/283ebd:30f:ffff:ffff:ffff:ffff:ffff:ffff
503ebd:310::/283ebd:31f:ffff:ffff:ffff:ffff:ffff:ffff
513ebd:320::/283ebd:32f:ffff:ffff:ffff:ffff:ffff:ffff
523ebd:330::/283ebd:33f:ffff:ffff:ffff:ffff:ffff:ffff
533ebd:340::/283ebd:34f:ffff:ffff:ffff:ffff:ffff:ffff
543ebd:350::/283ebd:35f:ffff:ffff:ffff:ffff:ffff:ffff
553ebd:360::/283ebd:36f:ffff:ffff:ffff:ffff:ffff:ffff
563ebd:370::/283ebd:37f:ffff:ffff:ffff:ffff:ffff:ffff
573ebd:380::/283ebd:38f:ffff:ffff:ffff:ffff:ffff:ffff
583ebd:390::/283ebd:39f:ffff:ffff:ffff:ffff:ffff:ffff
593ebd:3a0::/283ebd:3af:ffff:ffff:ffff:ffff:ffff:ffff
603ebd:3b0::/283ebd:3bf:ffff:ffff:ffff:ffff:ffff:ffff
613ebd:3c0::/283ebd:3cf:ffff:ffff:ffff:ffff:ffff:ffff
623ebd:3d0::/283ebd:3df:ffff:ffff:ffff:ffff:ffff:ffff
633ebd:3e0::/283ebd:3ef:ffff:ffff:ffff:ffff:ffff:ffff
643ebd:3f0::/283ebd:3ff:ffff:ffff:ffff:ffff:ffff:ffff
653ebd:400::/283ebd:40f:ffff:ffff:ffff:ffff:ffff:ffff
663ebd:410::/283ebd:41f:ffff:ffff:ffff:ffff:ffff:ffff
673ebd:420::/283ebd:42f:ffff:ffff:ffff:ffff:ffff:ffff
683ebd:430::/283ebd:43f:ffff:ffff:ffff:ffff:ffff:ffff
693ebd:440::/283ebd:44f:ffff:ffff:ffff:ffff:ffff:ffff
703ebd:450::/283ebd:45f:ffff:ffff:ffff:ffff:ffff:ffff
713ebd:460::/283ebd:46f:ffff:ffff:ffff:ffff:ffff:ffff
723ebd:470::/283ebd:47f:ffff:ffff:ffff:ffff:ffff:ffff
733ebd:480::/283ebd:48f:ffff:ffff:ffff:ffff:ffff:ffff
743ebd:490::/283ebd:49f:ffff:ffff:ffff:ffff:ffff:ffff
753ebd:4a0::/283ebd:4af:ffff:ffff:ffff:ffff:ffff:ffff
763ebd:4b0::/283ebd:4bf:ffff:ffff:ffff:ffff:ffff:ffff
773ebd:4c0::/283ebd:4cf:ffff:ffff:ffff:ffff:ffff:ffff
783ebd:4d0::/283ebd:4df:ffff:ffff:ffff:ffff:ffff:ffff
793ebd:4e0::/283ebd:4ef:ffff:ffff:ffff:ffff:ffff:ffff
803ebd:4f0::/283ebd:4ff:ffff:ffff:ffff:ffff:ffff:ffff
813ebd:500::/283ebd:50f:ffff:ffff:ffff:ffff:ffff:ffff
823ebd:510::/283ebd:51f:ffff:ffff:ffff:ffff:ffff:ffff
833ebd:520::/283ebd:52f:ffff:ffff:ffff:ffff:ffff:ffff
843ebd:530::/283ebd:53f:ffff:ffff:ffff:ffff:ffff:ffff
853ebd:540::/283ebd:54f:ffff:ffff:ffff:ffff:ffff:ffff
863ebd:550::/283ebd:55f:ffff:ffff:ffff:ffff:ffff:ffff
873ebd:560::/283ebd:56f:ffff:ffff:ffff:ffff:ffff:ffff
883ebd:570::/283ebd:57f:ffff:ffff:ffff:ffff:ffff:ffff
893ebd:580::/283ebd:58f:ffff:ffff:ffff:ffff:ffff:ffff
903ebd:590::/283ebd:59f:ffff:ffff:ffff:ffff:ffff:ffff
913ebd:5a0::/283ebd:5af:ffff:ffff:ffff:ffff:ffff:ffff
923ebd:5b0::/283ebd:5bf:ffff:ffff:ffff:ffff:ffff:ffff
933ebd:5c0::/283ebd:5cf:ffff:ffff:ffff:ffff:ffff:ffff
943ebd:5d0::/283ebd:5df:ffff:ffff:ffff:ffff:ffff:ffff
953ebd:5e0::/283ebd:5ef:ffff:ffff:ffff:ffff:ffff:ffff
963ebd:5f0::/283ebd:5ff:ffff:ffff:ffff:ffff:ffff:ffff
973ebd:600::/283ebd:60f:ffff:ffff:ffff:ffff:ffff:ffff
983ebd:610::/283ebd:61f:ffff:ffff:ffff:ffff:ffff:ffff
993ebd:620::/283ebd:62f:ffff:ffff:ffff:ffff:ffff:ffff
1003ebd:630::/283ebd:63f:ffff:ffff:ffff:ffff:ffff:ffff
1013ebd:640::/283ebd:64f:ffff:ffff:ffff:ffff:ffff:ffff
1023ebd:650::/283ebd:65f:ffff:ffff:ffff:ffff:ffff:ffff
1033ebd:660::/283ebd:66f:ffff:ffff:ffff:ffff:ffff:ffff
1043ebd:670::/283ebd:67f:ffff:ffff:ffff:ffff:ffff:ffff
1053ebd:680::/283ebd:68f:ffff:ffff:ffff:ffff:ffff:ffff
1063ebd:690::/283ebd:69f:ffff:ffff:ffff:ffff:ffff:ffff
1073ebd:6a0::/283ebd:6af:ffff:ffff:ffff:ffff:ffff:ffff
1083ebd:6b0::/283ebd:6bf:ffff:ffff:ffff:ffff:ffff:ffff
1093ebd:6c0::/283ebd:6cf:ffff:ffff:ffff:ffff:ffff:ffff
1103ebd:6d0::/283ebd:6df:ffff:ffff:ffff:ffff:ffff:ffff
1113ebd:6e0::/283ebd:6ef:ffff:ffff:ffff:ffff:ffff:ffff
1123ebd:6f0::/283ebd:6ff:ffff:ffff:ffff:ffff:ffff:ffff
1133ebd:700::/283ebd:70f:ffff:ffff:ffff:ffff:ffff:ffff
1143ebd:710::/283ebd:71f:ffff:ffff:ffff:ffff:ffff:ffff
1153ebd:720::/283ebd:72f:ffff:ffff:ffff:ffff:ffff:ffff
1163ebd:730::/283ebd:73f:ffff:ffff:ffff:ffff:ffff:ffff
1173ebd:740::/283ebd:74f:ffff:ffff:ffff:ffff:ffff:ffff
1183ebd:750::/283ebd:75f:ffff:ffff:ffff:ffff:ffff:ffff
1193ebd:760::/283ebd:76f:ffff:ffff:ffff:ffff:ffff:ffff
1203ebd:770::/283ebd:77f:ffff:ffff:ffff:ffff:ffff:ffff
1213ebd:780::/283ebd:78f:ffff:ffff:ffff:ffff:ffff:ffff
1223ebd:790::/283ebd:79f:ffff:ffff:ffff:ffff:ffff:ffff
1233ebd:7a0::/283ebd:7af:ffff:ffff:ffff:ffff:ffff:ffff
1243ebd:7b0::/283ebd:7bf:ffff:ffff:ffff:ffff:ffff:ffff
1253ebd:7c0::/283ebd:7cf:ffff:ffff:ffff:ffff:ffff:ffff
1263ebd:7d0::/283ebd:7df:ffff:ffff:ffff:ffff:ffff:ffff
1273ebd:7e0::/283ebd:7ef:ffff:ffff:ffff:ffff:ffff:ffff
1283ebd:7f0::/283ebd:7ff:ffff:ffff:ffff:ffff:ffff:ffff
1293ebd:800::/283ebd:80f:ffff:ffff:ffff:ffff:ffff:ffff
1303ebd:810::/283ebd:81f:ffff:ffff:ffff:ffff:ffff:ffff
1313ebd:820::/283ebd:82f:ffff:ffff:ffff:ffff:ffff:ffff
1323ebd:830::/283ebd:83f:ffff:ffff:ffff:ffff:ffff:ffff
1333ebd:840::/283ebd:84f:ffff:ffff:ffff:ffff:ffff:ffff
1343ebd:850::/283ebd:85f:ffff:ffff:ffff:ffff:ffff:ffff
1353ebd:860::/283ebd:86f:ffff:ffff:ffff:ffff:ffff:ffff
1363ebd:870::/283ebd:87f:ffff:ffff:ffff:ffff:ffff:ffff
1373ebd:880::/283ebd:88f:ffff:ffff:ffff:ffff:ffff:ffff
1383ebd:890::/283ebd:89f:ffff:ffff:ffff:ffff:ffff:ffff
1393ebd:8a0::/283ebd:8af:ffff:ffff:ffff:ffff:ffff:ffff
1403ebd:8b0::/283ebd:8bf:ffff:ffff:ffff:ffff:ffff:ffff
1413ebd:8c0::/283ebd:8cf:ffff:ffff:ffff:ffff:ffff:ffff
1423ebd:8d0::/283ebd:8df:ffff:ffff:ffff:ffff:ffff:ffff
1433ebd:8e0::/283ebd:8ef:ffff:ffff:ffff:ffff:ffff:ffff
1443ebd:8f0::/283ebd:8ff:ffff:ffff:ffff:ffff:ffff:ffff
1453ebd:900::/283ebd:90f:ffff:ffff:ffff:ffff:ffff:ffff
1463ebd:910::/283ebd:91f:ffff:ffff:ffff:ffff:ffff:ffff
1473ebd:920::/283ebd:92f:ffff:ffff:ffff:ffff:ffff:ffff
1483ebd:930::/283ebd:93f:ffff:ffff:ffff:ffff:ffff:ffff
1493ebd:940::/283ebd:94f:ffff:ffff:ffff:ffff:ffff:ffff
1503ebd:950::/283ebd:95f:ffff:ffff:ffff:ffff:ffff:ffff
1513ebd:960::/283ebd:96f:ffff:ffff:ffff:ffff:ffff:ffff
1523ebd:970::/283ebd:97f:ffff:ffff:ffff:ffff:ffff:ffff
1533ebd:980::/283ebd:98f:ffff:ffff:ffff:ffff:ffff:ffff
1543ebd:990::/283ebd:99f:ffff:ffff:ffff:ffff:ffff:ffff
1553ebd:9a0::/283ebd:9af:ffff:ffff:ffff:ffff:ffff:ffff
1563ebd:9b0::/283ebd:9bf:ffff:ffff:ffff:ffff:ffff:ffff
1573ebd:9c0::/283ebd:9cf:ffff:ffff:ffff:ffff:ffff:ffff
1583ebd:9d0::/283ebd:9df:ffff:ffff:ffff:ffff:ffff:ffff
1593ebd:9e0::/283ebd:9ef:ffff:ffff:ffff:ffff:ffff:ffff
1603ebd:9f0::/283ebd:9ff:ffff:ffff:ffff:ffff:ffff:ffff
1613ebd:a00::/283ebd:a0f:ffff:ffff:ffff:ffff:ffff:ffff
1623ebd:a10::/283ebd:a1f:ffff:ffff:ffff:ffff:ffff:ffff
1633ebd:a20::/283ebd:a2f:ffff:ffff:ffff:ffff:ffff:ffff
1643ebd:a30::/283ebd:a3f:ffff:ffff:ffff:ffff:ffff:ffff
1653ebd:a40::/283ebd:a4f:ffff:ffff:ffff:ffff:ffff:ffff
1663ebd:a50::/283ebd:a5f:ffff:ffff:ffff:ffff:ffff:ffff
1673ebd:a60::/283ebd:a6f:ffff:ffff:ffff:ffff:ffff:ffff
1683ebd:a70::/283ebd:a7f:ffff:ffff:ffff:ffff:ffff:ffff
1693ebd:a80::/283ebd:a8f:ffff:ffff:ffff:ffff:ffff:ffff
1703ebd:a90::/283ebd:a9f:ffff:ffff:ffff:ffff:ffff:ffff
1713ebd:aa0::/283ebd:aaf:ffff:ffff:ffff:ffff:ffff:ffff
1723ebd:ab0::/283ebd:abf:ffff:ffff:ffff:ffff:ffff:ffff
1733ebd:ac0::/283ebd:acf:ffff:ffff:ffff:ffff:ffff:ffff
1743ebd:ad0::/283ebd:adf:ffff:ffff:ffff:ffff:ffff:ffff
1753ebd:ae0::/283ebd:aef:ffff:ffff:ffff:ffff:ffff:ffff
1763ebd:af0::/283ebd:aff:ffff:ffff:ffff:ffff:ffff:ffff
1773ebd:b00::/283ebd:b0f:ffff:ffff:ffff:ffff:ffff:ffff
1783ebd:b10::/283ebd:b1f:ffff:ffff:ffff:ffff:ffff:ffff
1793ebd:b20::/283ebd:b2f:ffff:ffff:ffff:ffff:ffff:ffff
1803ebd:b30::/283ebd:b3f:ffff:ffff:ffff:ffff:ffff:ffff
1813ebd:b40::/283ebd:b4f:ffff:ffff:ffff:ffff:ffff:ffff
1823ebd:b50::/283ebd:b5f:ffff:ffff:ffff:ffff:ffff:ffff
1833ebd:b60::/283ebd:b6f:ffff:ffff:ffff:ffff:ffff:ffff
1843ebd:b70::/283ebd:b7f:ffff:ffff:ffff:ffff:ffff:ffff
1853ebd:b80::/283ebd:b8f:ffff:ffff:ffff:ffff:ffff:ffff
1863ebd:b90::/283ebd:b9f:ffff:ffff:ffff:ffff:ffff:ffff
1873ebd:ba0::/283ebd:baf:ffff:ffff:ffff:ffff:ffff:ffff
1883ebd:bb0::/283ebd:bbf:ffff:ffff:ffff:ffff:ffff:ffff
1893ebd:bc0::/283ebd:bcf:ffff:ffff:ffff:ffff:ffff:ffff
1903ebd:bd0::/283ebd:bdf:ffff:ffff:ffff:ffff:ffff:ffff
1913ebd:be0::/283ebd:bef:ffff:ffff:ffff:ffff:ffff:ffff
1923ebd:bf0::/283ebd:bff:ffff:ffff:ffff:ffff:ffff:ffff
1933ebd:c00::/283ebd:c0f:ffff:ffff:ffff:ffff:ffff:ffff
1943ebd:c10::/283ebd:c1f:ffff:ffff:ffff:ffff:ffff:ffff
1953ebd:c20::/283ebd:c2f:ffff:ffff:ffff:ffff:ffff:ffff
1963ebd:c30::/283ebd:c3f:ffff:ffff:ffff:ffff:ffff:ffff
1973ebd:c40::/283ebd:c4f:ffff:ffff:ffff:ffff:ffff:ffff
1983ebd:c50::/283ebd:c5f:ffff:ffff:ffff:ffff:ffff:ffff
1993ebd:c60::/283ebd:c6f:ffff:ffff:ffff:ffff:ffff:ffff
2003ebd:c70::/283ebd:c7f:ffff:ffff:ffff:ffff:ffff:ffff
2013ebd:c80::/283ebd:c8f:ffff:ffff:ffff:ffff:ffff:ffff
2023ebd:c90::/283ebd:c9f:ffff:ffff:ffff:ffff:ffff:ffff
2033ebd:ca0::/283ebd:caf:ffff:ffff:ffff:ffff:ffff:ffff
2043ebd:cb0::/283ebd:cbf:ffff:ffff:ffff:ffff:ffff:ffff
2053ebd:cc0::/283ebd:ccf:ffff:ffff:ffff:ffff:ffff:ffff
2063ebd:cd0::/283ebd:cdf:ffff:ffff:ffff:ffff:ffff:ffff
2073ebd:ce0::/283ebd:cef:ffff:ffff:ffff:ffff:ffff:ffff
2083ebd:cf0::/283ebd:cff:ffff:ffff:ffff:ffff:ffff:ffff
2093ebd:d00::/283ebd:d0f:ffff:ffff:ffff:ffff:ffff:ffff
2103ebd:d10::/283ebd:d1f:ffff:ffff:ffff:ffff:ffff:ffff
2113ebd:d20::/283ebd:d2f:ffff:ffff:ffff:ffff:ffff:ffff
2123ebd:d30::/283ebd:d3f:ffff:ffff:ffff:ffff:ffff:ffff
2133ebd:d40::/283ebd:d4f:ffff:ffff:ffff:ffff:ffff:ffff
2143ebd:d50::/283ebd:d5f:ffff:ffff:ffff:ffff:ffff:ffff
2153ebd:d60::/283ebd:d6f:ffff:ffff:ffff:ffff:ffff:ffff
2163ebd:d70::/283ebd:d7f:ffff:ffff:ffff:ffff:ffff:ffff
2173ebd:d80::/283ebd:d8f:ffff:ffff:ffff:ffff:ffff:ffff
2183ebd:d90::/283ebd:d9f:ffff:ffff:ffff:ffff:ffff:ffff
2193ebd:da0::/283ebd:daf:ffff:ffff:ffff:ffff:ffff:ffff
2203ebd:db0::/283ebd:dbf:ffff:ffff:ffff:ffff:ffff:ffff
2213ebd:dc0::/283ebd:dcf:ffff:ffff:ffff:ffff:ffff:ffff
2223ebd:dd0::/283ebd:ddf:ffff:ffff:ffff:ffff:ffff:ffff
2233ebd:de0::/283ebd:def:ffff:ffff:ffff:ffff:ffff:ffff
2243ebd:df0::/283ebd:dff:ffff:ffff:ffff:ffff:ffff:ffff
2253ebd:e00::/283ebd:e0f:ffff:ffff:ffff:ffff:ffff:ffff
2263ebd:e10::/283ebd:e1f:ffff:ffff:ffff:ffff:ffff:ffff
2273ebd:e20::/283ebd:e2f:ffff:ffff:ffff:ffff:ffff:ffff
2283ebd:e30::/283ebd:e3f:ffff:ffff:ffff:ffff:ffff:ffff
2293ebd:e40::/283ebd:e4f:ffff:ffff:ffff:ffff:ffff:ffff
2303ebd:e50::/283ebd:e5f:ffff:ffff:ffff:ffff:ffff:ffff
2313ebd:e60::/283ebd:e6f:ffff:ffff:ffff:ffff:ffff:ffff
2323ebd:e70::/283ebd:e7f:ffff:ffff:ffff:ffff:ffff:ffff
2333ebd:e80::/283ebd:e8f:ffff:ffff:ffff:ffff:ffff:ffff
2343ebd:e90::/283ebd:e9f:ffff:ffff:ffff:ffff:ffff:ffff
2353ebd:ea0::/283ebd:eaf:ffff:ffff:ffff:ffff:ffff:ffff
2363ebd:eb0::/283ebd:ebf:ffff:ffff:ffff:ffff:ffff:ffff
2373ebd:ec0::/283ebd:ecf:ffff:ffff:ffff:ffff:ffff:ffff
2383ebd:ed0::/283ebd:edf:ffff:ffff:ffff:ffff:ffff:ffff
2393ebd:ee0::/283ebd:eef:ffff:ffff:ffff:ffff:ffff:ffff
2403ebd:ef0::/283ebd:eff:ffff:ffff:ffff:ffff:ffff:ffff
2413ebd:f00::/283ebd:f0f:ffff:ffff:ffff:ffff:ffff:ffff
2423ebd:f10::/283ebd:f1f:ffff:ffff:ffff:ffff:ffff:ffff
2433ebd:f20::/283ebd:f2f:ffff:ffff:ffff:ffff:ffff:ffff
2443ebd:f30::/283ebd:f3f:ffff:ffff:ffff:ffff:ffff:ffff
2453ebd:f40::/283ebd:f4f:ffff:ffff:ffff:ffff:ffff:ffff
2463ebd:f50::/283ebd:f5f:ffff:ffff:ffff:ffff:ffff:ffff
2473ebd:f60::/283ebd:f6f:ffff:ffff:ffff:ffff:ffff:ffff
2483ebd:f70::/283ebd:f7f:ffff:ffff:ffff:ffff:ffff:ffff
2493ebd:f80::/283ebd:f8f:ffff:ffff:ffff:ffff:ffff:ffff
2503ebd:f90::/283ebd:f9f:ffff:ffff:ffff:ffff:ffff:ffff
2513ebd:fa0::/283ebd:faf:ffff:ffff:ffff:ffff:ffff:ffff
2523ebd:fb0::/283ebd:fbf:ffff:ffff:ffff:ffff:ffff:ffff
2533ebd:fc0::/283ebd:fcf:ffff:ffff:ffff:ffff:ffff:ffff
2543ebd:fd0::/283ebd:fdf:ffff:ffff:ffff:ffff:ffff:ffff
2553ebd:fe0::/283ebd:fef:ffff:ffff:ffff:ffff:ffff:ffff
2563ebd:ff0::/283ebd: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.