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

3eea::/16 makes 65,536 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
13eea::/323eea:0:ffff:ffff:ffff:ffff:ffff:ffff
23eea:1::/323eea:1:ffff:ffff:ffff:ffff:ffff:ffff
33eea:2::/323eea:2:ffff:ffff:ffff:ffff:ffff:ffff
43eea:3::/323eea:3:ffff:ffff:ffff:ffff:ffff:ffff
53eea:4::/323eea:4:ffff:ffff:ffff:ffff:ffff:ffff
63eea:5::/323eea:5:ffff:ffff:ffff:ffff:ffff:ffff
73eea:6::/323eea:6:ffff:ffff:ffff:ffff:ffff:ffff
83eea:7::/323eea:7:ffff:ffff:ffff:ffff:ffff:ffff
93eea:8::/323eea:8:ffff:ffff:ffff:ffff:ffff:ffff
103eea:9::/323eea:9:ffff:ffff:ffff:ffff:ffff:ffff
113eea:a::/323eea:a:ffff:ffff:ffff:ffff:ffff:ffff
123eea:b::/323eea:b:ffff:ffff:ffff:ffff:ffff:ffff
133eea:c::/323eea:c:ffff:ffff:ffff:ffff:ffff:ffff
143eea:d::/323eea:d:ffff:ffff:ffff:ffff:ffff:ffff
153eea:e::/323eea:e:ffff:ffff:ffff:ffff:ffff:ffff
163eea:f::/323eea:f:ffff:ffff:ffff:ffff:ffff:ffff
173eea:10::/323eea:10:ffff:ffff:ffff:ffff:ffff:ffff
183eea:11::/323eea:11:ffff:ffff:ffff:ffff:ffff:ffff
193eea:12::/323eea:12:ffff:ffff:ffff:ffff:ffff:ffff
203eea:13::/323eea:13:ffff:ffff:ffff:ffff:ffff:ffff
213eea:14::/323eea:14:ffff:ffff:ffff:ffff:ffff:ffff
223eea:15::/323eea:15:ffff:ffff:ffff:ffff:ffff:ffff
233eea:16::/323eea:16:ffff:ffff:ffff:ffff:ffff:ffff
243eea:17::/323eea:17:ffff:ffff:ffff:ffff:ffff:ffff
253eea:18::/323eea:18:ffff:ffff:ffff:ffff:ffff:ffff
263eea:19::/323eea:19:ffff:ffff:ffff:ffff:ffff:ffff
273eea:1a::/323eea:1a:ffff:ffff:ffff:ffff:ffff:ffff
283eea:1b::/323eea:1b:ffff:ffff:ffff:ffff:ffff:ffff
293eea:1c::/323eea:1c:ffff:ffff:ffff:ffff:ffff:ffff
303eea:1d::/323eea:1d:ffff:ffff:ffff:ffff:ffff:ffff
313eea:1e::/323eea:1e:ffff:ffff:ffff:ffff:ffff:ffff
323eea:1f::/323eea:1f:ffff:ffff:ffff:ffff:ffff:ffff
333eea:20::/323eea:20:ffff:ffff:ffff:ffff:ffff:ffff
343eea:21::/323eea:21:ffff:ffff:ffff:ffff:ffff:ffff
353eea:22::/323eea:22:ffff:ffff:ffff:ffff:ffff:ffff
363eea:23::/323eea:23:ffff:ffff:ffff:ffff:ffff:ffff
373eea:24::/323eea:24:ffff:ffff:ffff:ffff:ffff:ffff
383eea:25::/323eea:25:ffff:ffff:ffff:ffff:ffff:ffff
393eea:26::/323eea:26:ffff:ffff:ffff:ffff:ffff:ffff
403eea:27::/323eea:27:ffff:ffff:ffff:ffff:ffff:ffff
413eea:28::/323eea:28:ffff:ffff:ffff:ffff:ffff:ffff
423eea:29::/323eea:29:ffff:ffff:ffff:ffff:ffff:ffff
433eea:2a::/323eea:2a:ffff:ffff:ffff:ffff:ffff:ffff
443eea:2b::/323eea:2b:ffff:ffff:ffff:ffff:ffff:ffff
453eea:2c::/323eea:2c:ffff:ffff:ffff:ffff:ffff:ffff
463eea:2d::/323eea:2d:ffff:ffff:ffff:ffff:ffff:ffff
473eea:2e::/323eea:2e:ffff:ffff:ffff:ffff:ffff:ffff
483eea:2f::/323eea:2f:ffff:ffff:ffff:ffff:ffff:ffff
493eea:30::/323eea:30:ffff:ffff:ffff:ffff:ffff:ffff
503eea:31::/323eea:31:ffff:ffff:ffff:ffff:ffff:ffff
513eea:32::/323eea:32:ffff:ffff:ffff:ffff:ffff:ffff
523eea:33::/323eea:33:ffff:ffff:ffff:ffff:ffff:ffff
533eea:34::/323eea:34:ffff:ffff:ffff:ffff:ffff:ffff
543eea:35::/323eea:35:ffff:ffff:ffff:ffff:ffff:ffff
553eea:36::/323eea:36:ffff:ffff:ffff:ffff:ffff:ffff
563eea:37::/323eea:37:ffff:ffff:ffff:ffff:ffff:ffff
573eea:38::/323eea:38:ffff:ffff:ffff:ffff:ffff:ffff
583eea:39::/323eea:39:ffff:ffff:ffff:ffff:ffff:ffff
593eea:3a::/323eea:3a:ffff:ffff:ffff:ffff:ffff:ffff
603eea:3b::/323eea:3b:ffff:ffff:ffff:ffff:ffff:ffff
613eea:3c::/323eea:3c:ffff:ffff:ffff:ffff:ffff:ffff
623eea:3d::/323eea:3d:ffff:ffff:ffff:ffff:ffff:ffff
633eea:3e::/323eea:3e:ffff:ffff:ffff:ffff:ffff:ffff
643eea:3f::/323eea:3f:ffff:ffff:ffff:ffff:ffff:ffff
653eea:40::/323eea:40:ffff:ffff:ffff:ffff:ffff:ffff
663eea:41::/323eea:41:ffff:ffff:ffff:ffff:ffff:ffff
673eea:42::/323eea:42:ffff:ffff:ffff:ffff:ffff:ffff
683eea:43::/323eea:43:ffff:ffff:ffff:ffff:ffff:ffff
693eea:44::/323eea:44:ffff:ffff:ffff:ffff:ffff:ffff
703eea:45::/323eea:45:ffff:ffff:ffff:ffff:ffff:ffff
713eea:46::/323eea:46:ffff:ffff:ffff:ffff:ffff:ffff
723eea:47::/323eea:47:ffff:ffff:ffff:ffff:ffff:ffff
733eea:48::/323eea:48:ffff:ffff:ffff:ffff:ffff:ffff
743eea:49::/323eea:49:ffff:ffff:ffff:ffff:ffff:ffff
753eea:4a::/323eea:4a:ffff:ffff:ffff:ffff:ffff:ffff
763eea:4b::/323eea:4b:ffff:ffff:ffff:ffff:ffff:ffff
773eea:4c::/323eea:4c:ffff:ffff:ffff:ffff:ffff:ffff
783eea:4d::/323eea:4d:ffff:ffff:ffff:ffff:ffff:ffff
793eea:4e::/323eea:4e:ffff:ffff:ffff:ffff:ffff:ffff
803eea:4f::/323eea:4f:ffff:ffff:ffff:ffff:ffff:ffff
813eea:50::/323eea:50:ffff:ffff:ffff:ffff:ffff:ffff
823eea:51::/323eea:51:ffff:ffff:ffff:ffff:ffff:ffff
833eea:52::/323eea:52:ffff:ffff:ffff:ffff:ffff:ffff
843eea:53::/323eea:53:ffff:ffff:ffff:ffff:ffff:ffff
853eea:54::/323eea:54:ffff:ffff:ffff:ffff:ffff:ffff
863eea:55::/323eea:55:ffff:ffff:ffff:ffff:ffff:ffff
873eea:56::/323eea:56:ffff:ffff:ffff:ffff:ffff:ffff
883eea:57::/323eea:57:ffff:ffff:ffff:ffff:ffff:ffff
893eea:58::/323eea:58:ffff:ffff:ffff:ffff:ffff:ffff
903eea:59::/323eea:59:ffff:ffff:ffff:ffff:ffff:ffff
913eea:5a::/323eea:5a:ffff:ffff:ffff:ffff:ffff:ffff
923eea:5b::/323eea:5b:ffff:ffff:ffff:ffff:ffff:ffff
933eea:5c::/323eea:5c:ffff:ffff:ffff:ffff:ffff:ffff
943eea:5d::/323eea:5d:ffff:ffff:ffff:ffff:ffff:ffff
953eea:5e::/323eea:5e:ffff:ffff:ffff:ffff:ffff:ffff
963eea:5f::/323eea:5f:ffff:ffff:ffff:ffff:ffff:ffff
973eea:60::/323eea:60:ffff:ffff:ffff:ffff:ffff:ffff
983eea:61::/323eea:61:ffff:ffff:ffff:ffff:ffff:ffff
993eea:62::/323eea:62:ffff:ffff:ffff:ffff:ffff:ffff
1003eea:63::/323eea:63:ffff:ffff:ffff:ffff:ffff:ffff
1013eea:64::/323eea:64:ffff:ffff:ffff:ffff:ffff:ffff
1023eea:65::/323eea:65:ffff:ffff:ffff:ffff:ffff:ffff
1033eea:66::/323eea:66:ffff:ffff:ffff:ffff:ffff:ffff
1043eea:67::/323eea:67:ffff:ffff:ffff:ffff:ffff:ffff
1053eea:68::/323eea:68:ffff:ffff:ffff:ffff:ffff:ffff
1063eea:69::/323eea:69:ffff:ffff:ffff:ffff:ffff:ffff
1073eea:6a::/323eea:6a:ffff:ffff:ffff:ffff:ffff:ffff
1083eea:6b::/323eea:6b:ffff:ffff:ffff:ffff:ffff:ffff
1093eea:6c::/323eea:6c:ffff:ffff:ffff:ffff:ffff:ffff
1103eea:6d::/323eea:6d:ffff:ffff:ffff:ffff:ffff:ffff
1113eea:6e::/323eea:6e:ffff:ffff:ffff:ffff:ffff:ffff
1123eea:6f::/323eea:6f:ffff:ffff:ffff:ffff:ffff:ffff
1133eea:70::/323eea:70:ffff:ffff:ffff:ffff:ffff:ffff
1143eea:71::/323eea:71:ffff:ffff:ffff:ffff:ffff:ffff
1153eea:72::/323eea:72:ffff:ffff:ffff:ffff:ffff:ffff
1163eea:73::/323eea:73:ffff:ffff:ffff:ffff:ffff:ffff
1173eea:74::/323eea:74:ffff:ffff:ffff:ffff:ffff:ffff
1183eea:75::/323eea:75:ffff:ffff:ffff:ffff:ffff:ffff
1193eea:76::/323eea:76:ffff:ffff:ffff:ffff:ffff:ffff
1203eea:77::/323eea:77:ffff:ffff:ffff:ffff:ffff:ffff
1213eea:78::/323eea:78:ffff:ffff:ffff:ffff:ffff:ffff
1223eea:79::/323eea:79:ffff:ffff:ffff:ffff:ffff:ffff
1233eea:7a::/323eea:7a:ffff:ffff:ffff:ffff:ffff:ffff
1243eea:7b::/323eea:7b:ffff:ffff:ffff:ffff:ffff:ffff
1253eea:7c::/323eea:7c:ffff:ffff:ffff:ffff:ffff:ffff
1263eea:7d::/323eea:7d:ffff:ffff:ffff:ffff:ffff:ffff
1273eea:7e::/323eea:7e:ffff:ffff:ffff:ffff:ffff:ffff
1283eea:7f::/323eea:7f:ffff:ffff:ffff:ffff:ffff:ffff
1293eea:80::/323eea:80:ffff:ffff:ffff:ffff:ffff:ffff
1303eea:81::/323eea:81:ffff:ffff:ffff:ffff:ffff:ffff
1313eea:82::/323eea:82:ffff:ffff:ffff:ffff:ffff:ffff
1323eea:83::/323eea:83:ffff:ffff:ffff:ffff:ffff:ffff
1333eea:84::/323eea:84:ffff:ffff:ffff:ffff:ffff:ffff
1343eea:85::/323eea:85:ffff:ffff:ffff:ffff:ffff:ffff
1353eea:86::/323eea:86:ffff:ffff:ffff:ffff:ffff:ffff
1363eea:87::/323eea:87:ffff:ffff:ffff:ffff:ffff:ffff
1373eea:88::/323eea:88:ffff:ffff:ffff:ffff:ffff:ffff
1383eea:89::/323eea:89:ffff:ffff:ffff:ffff:ffff:ffff
1393eea:8a::/323eea:8a:ffff:ffff:ffff:ffff:ffff:ffff
1403eea:8b::/323eea:8b:ffff:ffff:ffff:ffff:ffff:ffff
1413eea:8c::/323eea:8c:ffff:ffff:ffff:ffff:ffff:ffff
1423eea:8d::/323eea:8d:ffff:ffff:ffff:ffff:ffff:ffff
1433eea:8e::/323eea:8e:ffff:ffff:ffff:ffff:ffff:ffff
1443eea:8f::/323eea:8f:ffff:ffff:ffff:ffff:ffff:ffff
1453eea:90::/323eea:90:ffff:ffff:ffff:ffff:ffff:ffff
1463eea:91::/323eea:91:ffff:ffff:ffff:ffff:ffff:ffff
1473eea:92::/323eea:92:ffff:ffff:ffff:ffff:ffff:ffff
1483eea:93::/323eea:93:ffff:ffff:ffff:ffff:ffff:ffff
1493eea:94::/323eea:94:ffff:ffff:ffff:ffff:ffff:ffff
1503eea:95::/323eea:95:ffff:ffff:ffff:ffff:ffff:ffff
1513eea:96::/323eea:96:ffff:ffff:ffff:ffff:ffff:ffff
1523eea:97::/323eea:97:ffff:ffff:ffff:ffff:ffff:ffff
1533eea:98::/323eea:98:ffff:ffff:ffff:ffff:ffff:ffff
1543eea:99::/323eea:99:ffff:ffff:ffff:ffff:ffff:ffff
1553eea:9a::/323eea:9a:ffff:ffff:ffff:ffff:ffff:ffff
1563eea:9b::/323eea:9b:ffff:ffff:ffff:ffff:ffff:ffff
1573eea:9c::/323eea:9c:ffff:ffff:ffff:ffff:ffff:ffff
1583eea:9d::/323eea:9d:ffff:ffff:ffff:ffff:ffff:ffff
1593eea:9e::/323eea:9e:ffff:ffff:ffff:ffff:ffff:ffff
1603eea:9f::/323eea:9f:ffff:ffff:ffff:ffff:ffff:ffff
1613eea:a0::/323eea:a0:ffff:ffff:ffff:ffff:ffff:ffff
1623eea:a1::/323eea:a1:ffff:ffff:ffff:ffff:ffff:ffff
1633eea:a2::/323eea:a2:ffff:ffff:ffff:ffff:ffff:ffff
1643eea:a3::/323eea:a3:ffff:ffff:ffff:ffff:ffff:ffff
1653eea:a4::/323eea:a4:ffff:ffff:ffff:ffff:ffff:ffff
1663eea:a5::/323eea:a5:ffff:ffff:ffff:ffff:ffff:ffff
1673eea:a6::/323eea:a6:ffff:ffff:ffff:ffff:ffff:ffff
1683eea:a7::/323eea:a7:ffff:ffff:ffff:ffff:ffff:ffff
1693eea:a8::/323eea:a8:ffff:ffff:ffff:ffff:ffff:ffff
1703eea:a9::/323eea:a9:ffff:ffff:ffff:ffff:ffff:ffff
1713eea:aa::/323eea:aa:ffff:ffff:ffff:ffff:ffff:ffff
1723eea:ab::/323eea:ab:ffff:ffff:ffff:ffff:ffff:ffff
1733eea:ac::/323eea:ac:ffff:ffff:ffff:ffff:ffff:ffff
1743eea:ad::/323eea:ad:ffff:ffff:ffff:ffff:ffff:ffff
1753eea:ae::/323eea:ae:ffff:ffff:ffff:ffff:ffff:ffff
1763eea:af::/323eea:af:ffff:ffff:ffff:ffff:ffff:ffff
1773eea:b0::/323eea:b0:ffff:ffff:ffff:ffff:ffff:ffff
1783eea:b1::/323eea:b1:ffff:ffff:ffff:ffff:ffff:ffff
1793eea:b2::/323eea:b2:ffff:ffff:ffff:ffff:ffff:ffff
1803eea:b3::/323eea:b3:ffff:ffff:ffff:ffff:ffff:ffff
1813eea:b4::/323eea:b4:ffff:ffff:ffff:ffff:ffff:ffff
1823eea:b5::/323eea:b5:ffff:ffff:ffff:ffff:ffff:ffff
1833eea:b6::/323eea:b6:ffff:ffff:ffff:ffff:ffff:ffff
1843eea:b7::/323eea:b7:ffff:ffff:ffff:ffff:ffff:ffff
1853eea:b8::/323eea:b8:ffff:ffff:ffff:ffff:ffff:ffff
1863eea:b9::/323eea:b9:ffff:ffff:ffff:ffff:ffff:ffff
1873eea:ba::/323eea:ba:ffff:ffff:ffff:ffff:ffff:ffff
1883eea:bb::/323eea:bb:ffff:ffff:ffff:ffff:ffff:ffff
1893eea:bc::/323eea:bc:ffff:ffff:ffff:ffff:ffff:ffff
1903eea:bd::/323eea:bd:ffff:ffff:ffff:ffff:ffff:ffff
1913eea:be::/323eea:be:ffff:ffff:ffff:ffff:ffff:ffff
1923eea:bf::/323eea:bf:ffff:ffff:ffff:ffff:ffff:ffff
1933eea:c0::/323eea:c0:ffff:ffff:ffff:ffff:ffff:ffff
1943eea:c1::/323eea:c1:ffff:ffff:ffff:ffff:ffff:ffff
1953eea:c2::/323eea:c2:ffff:ffff:ffff:ffff:ffff:ffff
1963eea:c3::/323eea:c3:ffff:ffff:ffff:ffff:ffff:ffff
1973eea:c4::/323eea:c4:ffff:ffff:ffff:ffff:ffff:ffff
1983eea:c5::/323eea:c5:ffff:ffff:ffff:ffff:ffff:ffff
1993eea:c6::/323eea:c6:ffff:ffff:ffff:ffff:ffff:ffff
2003eea:c7::/323eea:c7:ffff:ffff:ffff:ffff:ffff:ffff
2013eea:c8::/323eea:c8:ffff:ffff:ffff:ffff:ffff:ffff
2023eea:c9::/323eea:c9:ffff:ffff:ffff:ffff:ffff:ffff
2033eea:ca::/323eea:ca:ffff:ffff:ffff:ffff:ffff:ffff
2043eea:cb::/323eea:cb:ffff:ffff:ffff:ffff:ffff:ffff
2053eea:cc::/323eea:cc:ffff:ffff:ffff:ffff:ffff:ffff
2063eea:cd::/323eea:cd:ffff:ffff:ffff:ffff:ffff:ffff
2073eea:ce::/323eea:ce:ffff:ffff:ffff:ffff:ffff:ffff
2083eea:cf::/323eea:cf:ffff:ffff:ffff:ffff:ffff:ffff
2093eea:d0::/323eea:d0:ffff:ffff:ffff:ffff:ffff:ffff
2103eea:d1::/323eea:d1:ffff:ffff:ffff:ffff:ffff:ffff
2113eea:d2::/323eea:d2:ffff:ffff:ffff:ffff:ffff:ffff
2123eea:d3::/323eea:d3:ffff:ffff:ffff:ffff:ffff:ffff
2133eea:d4::/323eea:d4:ffff:ffff:ffff:ffff:ffff:ffff
2143eea:d5::/323eea:d5:ffff:ffff:ffff:ffff:ffff:ffff
2153eea:d6::/323eea:d6:ffff:ffff:ffff:ffff:ffff:ffff
2163eea:d7::/323eea:d7:ffff:ffff:ffff:ffff:ffff:ffff
2173eea:d8::/323eea:d8:ffff:ffff:ffff:ffff:ffff:ffff
2183eea:d9::/323eea:d9:ffff:ffff:ffff:ffff:ffff:ffff
2193eea:da::/323eea:da:ffff:ffff:ffff:ffff:ffff:ffff
2203eea:db::/323eea:db:ffff:ffff:ffff:ffff:ffff:ffff
2213eea:dc::/323eea:dc:ffff:ffff:ffff:ffff:ffff:ffff
2223eea:dd::/323eea:dd:ffff:ffff:ffff:ffff:ffff:ffff
2233eea:de::/323eea:de:ffff:ffff:ffff:ffff:ffff:ffff
2243eea:df::/323eea:df:ffff:ffff:ffff:ffff:ffff:ffff
2253eea:e0::/323eea:e0:ffff:ffff:ffff:ffff:ffff:ffff
2263eea:e1::/323eea:e1:ffff:ffff:ffff:ffff:ffff:ffff
2273eea:e2::/323eea:e2:ffff:ffff:ffff:ffff:ffff:ffff
2283eea:e3::/323eea:e3:ffff:ffff:ffff:ffff:ffff:ffff
2293eea:e4::/323eea:e4:ffff:ffff:ffff:ffff:ffff:ffff
2303eea:e5::/323eea:e5:ffff:ffff:ffff:ffff:ffff:ffff
2313eea:e6::/323eea:e6:ffff:ffff:ffff:ffff:ffff:ffff
2323eea:e7::/323eea:e7:ffff:ffff:ffff:ffff:ffff:ffff
2333eea:e8::/323eea:e8:ffff:ffff:ffff:ffff:ffff:ffff
2343eea:e9::/323eea:e9:ffff:ffff:ffff:ffff:ffff:ffff
2353eea:ea::/323eea:ea:ffff:ffff:ffff:ffff:ffff:ffff
2363eea:eb::/323eea:eb:ffff:ffff:ffff:ffff:ffff:ffff
2373eea:ec::/323eea:ec:ffff:ffff:ffff:ffff:ffff:ffff
2383eea:ed::/323eea:ed:ffff:ffff:ffff:ffff:ffff:ffff
2393eea:ee::/323eea:ee:ffff:ffff:ffff:ffff:ffff:ffff
2403eea:ef::/323eea:ef:ffff:ffff:ffff:ffff:ffff:ffff
2413eea:f0::/323eea:f0:ffff:ffff:ffff:ffff:ffff:ffff
2423eea:f1::/323eea:f1:ffff:ffff:ffff:ffff:ffff:ffff
2433eea:f2::/323eea:f2:ffff:ffff:ffff:ffff:ffff:ffff
2443eea:f3::/323eea:f3:ffff:ffff:ffff:ffff:ffff:ffff
2453eea:f4::/323eea:f4:ffff:ffff:ffff:ffff:ffff:ffff
2463eea:f5::/323eea:f5:ffff:ffff:ffff:ffff:ffff:ffff
2473eea:f6::/323eea:f6:ffff:ffff:ffff:ffff:ffff:ffff
2483eea:f7::/323eea:f7:ffff:ffff:ffff:ffff:ffff:ffff
2493eea:f8::/323eea:f8:ffff:ffff:ffff:ffff:ffff:ffff
2503eea:f9::/323eea:f9:ffff:ffff:ffff:ffff:ffff:ffff
2513eea:fa::/323eea:fa:ffff:ffff:ffff:ffff:ffff:ffff
2523eea:fb::/323eea:fb:ffff:ffff:ffff:ffff:ffff:ffff
2533eea:fc::/323eea:fc:ffff:ffff:ffff:ffff:ffff:ffff
2543eea:fd::/323eea:fd:ffff:ffff:ffff:ffff:ffff:ffff
2553eea:fe::/323eea:fe:ffff:ffff:ffff:ffff:ffff:ffff
2563eea:ff::/323eea:ff: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.