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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
2ea0::/12
First address
2ea0::
Last address
2eaf: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
2ea0:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
a.e.2.ip6.arpa
Split into smaller subnets/20
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2ea0::/12 makes 256 subnets of /20.

Subnets
#SubnetLast address
12ea0::/202ea0:fff:ffff:ffff:ffff:ffff:ffff:ffff
22ea0:1000::/202ea0:1fff:ffff:ffff:ffff:ffff:ffff:ffff
32ea0:2000::/202ea0:2fff:ffff:ffff:ffff:ffff:ffff:ffff
42ea0:3000::/202ea0:3fff:ffff:ffff:ffff:ffff:ffff:ffff
52ea0:4000::/202ea0:4fff:ffff:ffff:ffff:ffff:ffff:ffff
62ea0:5000::/202ea0:5fff:ffff:ffff:ffff:ffff:ffff:ffff
72ea0:6000::/202ea0:6fff:ffff:ffff:ffff:ffff:ffff:ffff
82ea0:7000::/202ea0:7fff:ffff:ffff:ffff:ffff:ffff:ffff
92ea0:8000::/202ea0:8fff:ffff:ffff:ffff:ffff:ffff:ffff
102ea0:9000::/202ea0:9fff:ffff:ffff:ffff:ffff:ffff:ffff
112ea0:a000::/202ea0:afff:ffff:ffff:ffff:ffff:ffff:ffff
122ea0:b000::/202ea0:bfff:ffff:ffff:ffff:ffff:ffff:ffff
132ea0:c000::/202ea0:cfff:ffff:ffff:ffff:ffff:ffff:ffff
142ea0:d000::/202ea0:dfff:ffff:ffff:ffff:ffff:ffff:ffff
152ea0:e000::/202ea0:efff:ffff:ffff:ffff:ffff:ffff:ffff
162ea0:f000::/202ea0:ffff:ffff:ffff:ffff:ffff:ffff:ffff
172ea1::/202ea1:fff:ffff:ffff:ffff:ffff:ffff:ffff
182ea1:1000::/202ea1:1fff:ffff:ffff:ffff:ffff:ffff:ffff
192ea1:2000::/202ea1:2fff:ffff:ffff:ffff:ffff:ffff:ffff
202ea1:3000::/202ea1:3fff:ffff:ffff:ffff:ffff:ffff:ffff
212ea1:4000::/202ea1:4fff:ffff:ffff:ffff:ffff:ffff:ffff
222ea1:5000::/202ea1:5fff:ffff:ffff:ffff:ffff:ffff:ffff
232ea1:6000::/202ea1:6fff:ffff:ffff:ffff:ffff:ffff:ffff
242ea1:7000::/202ea1:7fff:ffff:ffff:ffff:ffff:ffff:ffff
252ea1:8000::/202ea1:8fff:ffff:ffff:ffff:ffff:ffff:ffff
262ea1:9000::/202ea1:9fff:ffff:ffff:ffff:ffff:ffff:ffff
272ea1:a000::/202ea1:afff:ffff:ffff:ffff:ffff:ffff:ffff
282ea1:b000::/202ea1:bfff:ffff:ffff:ffff:ffff:ffff:ffff
292ea1:c000::/202ea1:cfff:ffff:ffff:ffff:ffff:ffff:ffff
302ea1:d000::/202ea1:dfff:ffff:ffff:ffff:ffff:ffff:ffff
312ea1:e000::/202ea1:efff:ffff:ffff:ffff:ffff:ffff:ffff
322ea1:f000::/202ea1:ffff:ffff:ffff:ffff:ffff:ffff:ffff
332ea2::/202ea2:fff:ffff:ffff:ffff:ffff:ffff:ffff
342ea2:1000::/202ea2:1fff:ffff:ffff:ffff:ffff:ffff:ffff
352ea2:2000::/202ea2:2fff:ffff:ffff:ffff:ffff:ffff:ffff
362ea2:3000::/202ea2:3fff:ffff:ffff:ffff:ffff:ffff:ffff
372ea2:4000::/202ea2:4fff:ffff:ffff:ffff:ffff:ffff:ffff
382ea2:5000::/202ea2:5fff:ffff:ffff:ffff:ffff:ffff:ffff
392ea2:6000::/202ea2:6fff:ffff:ffff:ffff:ffff:ffff:ffff
402ea2:7000::/202ea2:7fff:ffff:ffff:ffff:ffff:ffff:ffff
412ea2:8000::/202ea2:8fff:ffff:ffff:ffff:ffff:ffff:ffff
422ea2:9000::/202ea2:9fff:ffff:ffff:ffff:ffff:ffff:ffff
432ea2:a000::/202ea2:afff:ffff:ffff:ffff:ffff:ffff:ffff
442ea2:b000::/202ea2:bfff:ffff:ffff:ffff:ffff:ffff:ffff
452ea2:c000::/202ea2:cfff:ffff:ffff:ffff:ffff:ffff:ffff
462ea2:d000::/202ea2:dfff:ffff:ffff:ffff:ffff:ffff:ffff
472ea2:e000::/202ea2:efff:ffff:ffff:ffff:ffff:ffff:ffff
482ea2:f000::/202ea2:ffff:ffff:ffff:ffff:ffff:ffff:ffff
492ea3::/202ea3:fff:ffff:ffff:ffff:ffff:ffff:ffff
502ea3:1000::/202ea3:1fff:ffff:ffff:ffff:ffff:ffff:ffff
512ea3:2000::/202ea3:2fff:ffff:ffff:ffff:ffff:ffff:ffff
522ea3:3000::/202ea3:3fff:ffff:ffff:ffff:ffff:ffff:ffff
532ea3:4000::/202ea3:4fff:ffff:ffff:ffff:ffff:ffff:ffff
542ea3:5000::/202ea3:5fff:ffff:ffff:ffff:ffff:ffff:ffff
552ea3:6000::/202ea3:6fff:ffff:ffff:ffff:ffff:ffff:ffff
562ea3:7000::/202ea3:7fff:ffff:ffff:ffff:ffff:ffff:ffff
572ea3:8000::/202ea3:8fff:ffff:ffff:ffff:ffff:ffff:ffff
582ea3:9000::/202ea3:9fff:ffff:ffff:ffff:ffff:ffff:ffff
592ea3:a000::/202ea3:afff:ffff:ffff:ffff:ffff:ffff:ffff
602ea3:b000::/202ea3:bfff:ffff:ffff:ffff:ffff:ffff:ffff
612ea3:c000::/202ea3:cfff:ffff:ffff:ffff:ffff:ffff:ffff
622ea3:d000::/202ea3:dfff:ffff:ffff:ffff:ffff:ffff:ffff
632ea3:e000::/202ea3:efff:ffff:ffff:ffff:ffff:ffff:ffff
642ea3:f000::/202ea3:ffff:ffff:ffff:ffff:ffff:ffff:ffff
652ea4::/202ea4:fff:ffff:ffff:ffff:ffff:ffff:ffff
662ea4:1000::/202ea4:1fff:ffff:ffff:ffff:ffff:ffff:ffff
672ea4:2000::/202ea4:2fff:ffff:ffff:ffff:ffff:ffff:ffff
682ea4:3000::/202ea4:3fff:ffff:ffff:ffff:ffff:ffff:ffff
692ea4:4000::/202ea4:4fff:ffff:ffff:ffff:ffff:ffff:ffff
702ea4:5000::/202ea4:5fff:ffff:ffff:ffff:ffff:ffff:ffff
712ea4:6000::/202ea4:6fff:ffff:ffff:ffff:ffff:ffff:ffff
722ea4:7000::/202ea4:7fff:ffff:ffff:ffff:ffff:ffff:ffff
732ea4:8000::/202ea4:8fff:ffff:ffff:ffff:ffff:ffff:ffff
742ea4:9000::/202ea4:9fff:ffff:ffff:ffff:ffff:ffff:ffff
752ea4:a000::/202ea4:afff:ffff:ffff:ffff:ffff:ffff:ffff
762ea4:b000::/202ea4:bfff:ffff:ffff:ffff:ffff:ffff:ffff
772ea4:c000::/202ea4:cfff:ffff:ffff:ffff:ffff:ffff:ffff
782ea4:d000::/202ea4:dfff:ffff:ffff:ffff:ffff:ffff:ffff
792ea4:e000::/202ea4:efff:ffff:ffff:ffff:ffff:ffff:ffff
802ea4:f000::/202ea4:ffff:ffff:ffff:ffff:ffff:ffff:ffff
812ea5::/202ea5:fff:ffff:ffff:ffff:ffff:ffff:ffff
822ea5:1000::/202ea5:1fff:ffff:ffff:ffff:ffff:ffff:ffff
832ea5:2000::/202ea5:2fff:ffff:ffff:ffff:ffff:ffff:ffff
842ea5:3000::/202ea5:3fff:ffff:ffff:ffff:ffff:ffff:ffff
852ea5:4000::/202ea5:4fff:ffff:ffff:ffff:ffff:ffff:ffff
862ea5:5000::/202ea5:5fff:ffff:ffff:ffff:ffff:ffff:ffff
872ea5:6000::/202ea5:6fff:ffff:ffff:ffff:ffff:ffff:ffff
882ea5:7000::/202ea5:7fff:ffff:ffff:ffff:ffff:ffff:ffff
892ea5:8000::/202ea5:8fff:ffff:ffff:ffff:ffff:ffff:ffff
902ea5:9000::/202ea5:9fff:ffff:ffff:ffff:ffff:ffff:ffff
912ea5:a000::/202ea5:afff:ffff:ffff:ffff:ffff:ffff:ffff
922ea5:b000::/202ea5:bfff:ffff:ffff:ffff:ffff:ffff:ffff
932ea5:c000::/202ea5:cfff:ffff:ffff:ffff:ffff:ffff:ffff
942ea5:d000::/202ea5:dfff:ffff:ffff:ffff:ffff:ffff:ffff
952ea5:e000::/202ea5:efff:ffff:ffff:ffff:ffff:ffff:ffff
962ea5:f000::/202ea5:ffff:ffff:ffff:ffff:ffff:ffff:ffff
972ea6::/202ea6:fff:ffff:ffff:ffff:ffff:ffff:ffff
982ea6:1000::/202ea6:1fff:ffff:ffff:ffff:ffff:ffff:ffff
992ea6:2000::/202ea6:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1002ea6:3000::/202ea6:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1012ea6:4000::/202ea6:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1022ea6:5000::/202ea6:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1032ea6:6000::/202ea6:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1042ea6:7000::/202ea6:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1052ea6:8000::/202ea6:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1062ea6:9000::/202ea6:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1072ea6:a000::/202ea6:afff:ffff:ffff:ffff:ffff:ffff:ffff
1082ea6:b000::/202ea6:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1092ea6:c000::/202ea6:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1102ea6:d000::/202ea6:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1112ea6:e000::/202ea6:efff:ffff:ffff:ffff:ffff:ffff:ffff
1122ea6:f000::/202ea6:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1132ea7::/202ea7:fff:ffff:ffff:ffff:ffff:ffff:ffff
1142ea7:1000::/202ea7:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1152ea7:2000::/202ea7:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1162ea7:3000::/202ea7:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1172ea7:4000::/202ea7:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1182ea7:5000::/202ea7:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1192ea7:6000::/202ea7:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1202ea7:7000::/202ea7:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1212ea7:8000::/202ea7:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1222ea7:9000::/202ea7:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1232ea7:a000::/202ea7:afff:ffff:ffff:ffff:ffff:ffff:ffff
1242ea7:b000::/202ea7:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1252ea7:c000::/202ea7:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1262ea7:d000::/202ea7:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1272ea7:e000::/202ea7:efff:ffff:ffff:ffff:ffff:ffff:ffff
1282ea7:f000::/202ea7:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1292ea8::/202ea8:fff:ffff:ffff:ffff:ffff:ffff:ffff
1302ea8:1000::/202ea8:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1312ea8:2000::/202ea8:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1322ea8:3000::/202ea8:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1332ea8:4000::/202ea8:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1342ea8:5000::/202ea8:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1352ea8:6000::/202ea8:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1362ea8:7000::/202ea8:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1372ea8:8000::/202ea8:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1382ea8:9000::/202ea8:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1392ea8:a000::/202ea8:afff:ffff:ffff:ffff:ffff:ffff:ffff
1402ea8:b000::/202ea8:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1412ea8:c000::/202ea8:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1422ea8:d000::/202ea8:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1432ea8:e000::/202ea8:efff:ffff:ffff:ffff:ffff:ffff:ffff
1442ea8:f000::/202ea8:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1452ea9::/202ea9:fff:ffff:ffff:ffff:ffff:ffff:ffff
1462ea9:1000::/202ea9:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1472ea9:2000::/202ea9:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1482ea9:3000::/202ea9:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1492ea9:4000::/202ea9:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1502ea9:5000::/202ea9:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1512ea9:6000::/202ea9:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1522ea9:7000::/202ea9:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1532ea9:8000::/202ea9:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1542ea9:9000::/202ea9:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1552ea9:a000::/202ea9:afff:ffff:ffff:ffff:ffff:ffff:ffff
1562ea9:b000::/202ea9:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1572ea9:c000::/202ea9:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1582ea9:d000::/202ea9:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1592ea9:e000::/202ea9:efff:ffff:ffff:ffff:ffff:ffff:ffff
1602ea9:f000::/202ea9:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1612eaa::/202eaa:fff:ffff:ffff:ffff:ffff:ffff:ffff
1622eaa:1000::/202eaa:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1632eaa:2000::/202eaa:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1642eaa:3000::/202eaa:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1652eaa:4000::/202eaa:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1662eaa:5000::/202eaa:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1672eaa:6000::/202eaa:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1682eaa:7000::/202eaa:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1692eaa:8000::/202eaa:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1702eaa:9000::/202eaa:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1712eaa:a000::/202eaa:afff:ffff:ffff:ffff:ffff:ffff:ffff
1722eaa:b000::/202eaa:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1732eaa:c000::/202eaa:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1742eaa:d000::/202eaa:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1752eaa:e000::/202eaa:efff:ffff:ffff:ffff:ffff:ffff:ffff
1762eaa:f000::/202eaa:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1772eab::/202eab:fff:ffff:ffff:ffff:ffff:ffff:ffff
1782eab:1000::/202eab:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1792eab:2000::/202eab:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1802eab:3000::/202eab:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1812eab:4000::/202eab:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1822eab:5000::/202eab:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1832eab:6000::/202eab:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1842eab:7000::/202eab:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1852eab:8000::/202eab:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1862eab:9000::/202eab:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1872eab:a000::/202eab:afff:ffff:ffff:ffff:ffff:ffff:ffff
1882eab:b000::/202eab:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1892eab:c000::/202eab:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1902eab:d000::/202eab:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1912eab:e000::/202eab:efff:ffff:ffff:ffff:ffff:ffff:ffff
1922eab:f000::/202eab:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1932eac::/202eac:fff:ffff:ffff:ffff:ffff:ffff:ffff
1942eac:1000::/202eac:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1952eac:2000::/202eac:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1962eac:3000::/202eac:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1972eac:4000::/202eac:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1982eac:5000::/202eac:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1992eac:6000::/202eac:6fff:ffff:ffff:ffff:ffff:ffff:ffff
2002eac:7000::/202eac:7fff:ffff:ffff:ffff:ffff:ffff:ffff
2012eac:8000::/202eac:8fff:ffff:ffff:ffff:ffff:ffff:ffff
2022eac:9000::/202eac:9fff:ffff:ffff:ffff:ffff:ffff:ffff
2032eac:a000::/202eac:afff:ffff:ffff:ffff:ffff:ffff:ffff
2042eac:b000::/202eac:bfff:ffff:ffff:ffff:ffff:ffff:ffff
2052eac:c000::/202eac:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2062eac:d000::/202eac:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2072eac:e000::/202eac:efff:ffff:ffff:ffff:ffff:ffff:ffff
2082eac:f000::/202eac:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2092ead::/202ead:fff:ffff:ffff:ffff:ffff:ffff:ffff
2102ead:1000::/202ead:1fff:ffff:ffff:ffff:ffff:ffff:ffff
2112ead:2000::/202ead:2fff:ffff:ffff:ffff:ffff:ffff:ffff
2122ead:3000::/202ead:3fff:ffff:ffff:ffff:ffff:ffff:ffff
2132ead:4000::/202ead:4fff:ffff:ffff:ffff:ffff:ffff:ffff
2142ead:5000::/202ead:5fff:ffff:ffff:ffff:ffff:ffff:ffff
2152ead:6000::/202ead:6fff:ffff:ffff:ffff:ffff:ffff:ffff
2162ead:7000::/202ead:7fff:ffff:ffff:ffff:ffff:ffff:ffff
2172ead:8000::/202ead:8fff:ffff:ffff:ffff:ffff:ffff:ffff
2182ead:9000::/202ead:9fff:ffff:ffff:ffff:ffff:ffff:ffff
2192ead:a000::/202ead:afff:ffff:ffff:ffff:ffff:ffff:ffff
2202ead:b000::/202ead:bfff:ffff:ffff:ffff:ffff:ffff:ffff
2212ead:c000::/202ead:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2222ead:d000::/202ead:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2232ead:e000::/202ead:efff:ffff:ffff:ffff:ffff:ffff:ffff
2242ead:f000::/202ead:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2252eae::/202eae:fff:ffff:ffff:ffff:ffff:ffff:ffff
2262eae:1000::/202eae:1fff:ffff:ffff:ffff:ffff:ffff:ffff
2272eae:2000::/202eae:2fff:ffff:ffff:ffff:ffff:ffff:ffff
2282eae:3000::/202eae:3fff:ffff:ffff:ffff:ffff:ffff:ffff
2292eae:4000::/202eae:4fff:ffff:ffff:ffff:ffff:ffff:ffff
2302eae:5000::/202eae:5fff:ffff:ffff:ffff:ffff:ffff:ffff
2312eae:6000::/202eae:6fff:ffff:ffff:ffff:ffff:ffff:ffff
2322eae:7000::/202eae:7fff:ffff:ffff:ffff:ffff:ffff:ffff
2332eae:8000::/202eae:8fff:ffff:ffff:ffff:ffff:ffff:ffff
2342eae:9000::/202eae:9fff:ffff:ffff:ffff:ffff:ffff:ffff
2352eae:a000::/202eae:afff:ffff:ffff:ffff:ffff:ffff:ffff
2362eae:b000::/202eae:bfff:ffff:ffff:ffff:ffff:ffff:ffff
2372eae:c000::/202eae:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2382eae:d000::/202eae:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2392eae:e000::/202eae:efff:ffff:ffff:ffff:ffff:ffff:ffff
2402eae:f000::/202eae:ffff:ffff:ffff:ffff:ffff:ffff:ffff
2412eaf::/202eaf:fff:ffff:ffff:ffff:ffff:ffff:ffff
2422eaf:1000::/202eaf:1fff:ffff:ffff:ffff:ffff:ffff:ffff
2432eaf:2000::/202eaf:2fff:ffff:ffff:ffff:ffff:ffff:ffff
2442eaf:3000::/202eaf:3fff:ffff:ffff:ffff:ffff:ffff:ffff
2452eaf:4000::/202eaf:4fff:ffff:ffff:ffff:ffff:ffff:ffff
2462eaf:5000::/202eaf:5fff:ffff:ffff:ffff:ffff:ffff:ffff
2472eaf:6000::/202eaf:6fff:ffff:ffff:ffff:ffff:ffff:ffff
2482eaf:7000::/202eaf:7fff:ffff:ffff:ffff:ffff:ffff:ffff
2492eaf:8000::/202eaf:8fff:ffff:ffff:ffff:ffff:ffff:ffff
2502eaf:9000::/202eaf:9fff:ffff:ffff:ffff:ffff:ffff:ffff
2512eaf:a000::/202eaf:afff:ffff:ffff:ffff:ffff:ffff:ffff
2522eaf:b000::/202eaf:bfff:ffff:ffff:ffff:ffff:ffff:ffff
2532eaf:c000::/202eaf:cfff:ffff:ffff:ffff:ffff:ffff:ffff
2542eaf:d000::/202eaf:dfff:ffff:ffff:ffff:ffff:ffff:ffff
2552eaf:e000::/202eaf:efff:ffff:ffff:ffff:ffff:ffff:ffff
2562eaf:f000::/202eaf:ffff: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.