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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.

Network4.8.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
4.8.0.0
Broadcast address
4.11.255.255
First usable
4.8.0.1
Last usable
4.11.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
A (default /8)
As numbers
Hex 04080000 · Integer 67633152 to 67895295
Reverse DNS zones
8.4.in-addr.arpa
9.4.in-addr.arpa
10.4.in-addr.arpa
11.4.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00000100.00001000.00000000.000000004.8.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00000100.00001000.00000000.000000004.8.0.0
Broadcast00000100.00001011.11111111.111111114.11.255.255
Split into smaller subnets/21

4.8.0.0/14 makes 128 subnets of /21.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
14.8.0.0/214.8.0.1 to 4.8.7.2544.8.7.2552,046
24.8.8.0/214.8.8.1 to 4.8.15.2544.8.15.2552,046
34.8.16.0/214.8.16.1 to 4.8.23.2544.8.23.2552,046
44.8.24.0/214.8.24.1 to 4.8.31.2544.8.31.2552,046
54.8.32.0/214.8.32.1 to 4.8.39.2544.8.39.2552,046
64.8.40.0/214.8.40.1 to 4.8.47.2544.8.47.2552,046
74.8.48.0/214.8.48.1 to 4.8.55.2544.8.55.2552,046
84.8.56.0/214.8.56.1 to 4.8.63.2544.8.63.2552,046
94.8.64.0/214.8.64.1 to 4.8.71.2544.8.71.2552,046
104.8.72.0/214.8.72.1 to 4.8.79.2544.8.79.2552,046
114.8.80.0/214.8.80.1 to 4.8.87.2544.8.87.2552,046
124.8.88.0/214.8.88.1 to 4.8.95.2544.8.95.2552,046
134.8.96.0/214.8.96.1 to 4.8.103.2544.8.103.2552,046
144.8.104.0/214.8.104.1 to 4.8.111.2544.8.111.2552,046
154.8.112.0/214.8.112.1 to 4.8.119.2544.8.119.2552,046
164.8.120.0/214.8.120.1 to 4.8.127.2544.8.127.2552,046
174.8.128.0/214.8.128.1 to 4.8.135.2544.8.135.2552,046
184.8.136.0/214.8.136.1 to 4.8.143.2544.8.143.2552,046
194.8.144.0/214.8.144.1 to 4.8.151.2544.8.151.2552,046
204.8.152.0/214.8.152.1 to 4.8.159.2544.8.159.2552,046
214.8.160.0/214.8.160.1 to 4.8.167.2544.8.167.2552,046
224.8.168.0/214.8.168.1 to 4.8.175.2544.8.175.2552,046
234.8.176.0/214.8.176.1 to 4.8.183.2544.8.183.2552,046
244.8.184.0/214.8.184.1 to 4.8.191.2544.8.191.2552,046
254.8.192.0/214.8.192.1 to 4.8.199.2544.8.199.2552,046
264.8.200.0/214.8.200.1 to 4.8.207.2544.8.207.2552,046
274.8.208.0/214.8.208.1 to 4.8.215.2544.8.215.2552,046
284.8.216.0/214.8.216.1 to 4.8.223.2544.8.223.2552,046
294.8.224.0/214.8.224.1 to 4.8.231.2544.8.231.2552,046
304.8.232.0/214.8.232.1 to 4.8.239.2544.8.239.2552,046
314.8.240.0/214.8.240.1 to 4.8.247.2544.8.247.2552,046
324.8.248.0/214.8.248.1 to 4.8.255.2544.8.255.2552,046
334.9.0.0/214.9.0.1 to 4.9.7.2544.9.7.2552,046
344.9.8.0/214.9.8.1 to 4.9.15.2544.9.15.2552,046
354.9.16.0/214.9.16.1 to 4.9.23.2544.9.23.2552,046
364.9.24.0/214.9.24.1 to 4.9.31.2544.9.31.2552,046
374.9.32.0/214.9.32.1 to 4.9.39.2544.9.39.2552,046
384.9.40.0/214.9.40.1 to 4.9.47.2544.9.47.2552,046
394.9.48.0/214.9.48.1 to 4.9.55.2544.9.55.2552,046
404.9.56.0/214.9.56.1 to 4.9.63.2544.9.63.2552,046
414.9.64.0/214.9.64.1 to 4.9.71.2544.9.71.2552,046
424.9.72.0/214.9.72.1 to 4.9.79.2544.9.79.2552,046
434.9.80.0/214.9.80.1 to 4.9.87.2544.9.87.2552,046
444.9.88.0/214.9.88.1 to 4.9.95.2544.9.95.2552,046
454.9.96.0/214.9.96.1 to 4.9.103.2544.9.103.2552,046
464.9.104.0/214.9.104.1 to 4.9.111.2544.9.111.2552,046
474.9.112.0/214.9.112.1 to 4.9.119.2544.9.119.2552,046
484.9.120.0/214.9.120.1 to 4.9.127.2544.9.127.2552,046
494.9.128.0/214.9.128.1 to 4.9.135.2544.9.135.2552,046
504.9.136.0/214.9.136.1 to 4.9.143.2544.9.143.2552,046
514.9.144.0/214.9.144.1 to 4.9.151.2544.9.151.2552,046
524.9.152.0/214.9.152.1 to 4.9.159.2544.9.159.2552,046
534.9.160.0/214.9.160.1 to 4.9.167.2544.9.167.2552,046
544.9.168.0/214.9.168.1 to 4.9.175.2544.9.175.2552,046
554.9.176.0/214.9.176.1 to 4.9.183.2544.9.183.2552,046
564.9.184.0/214.9.184.1 to 4.9.191.2544.9.191.2552,046
574.9.192.0/214.9.192.1 to 4.9.199.2544.9.199.2552,046
584.9.200.0/214.9.200.1 to 4.9.207.2544.9.207.2552,046
594.9.208.0/214.9.208.1 to 4.9.215.2544.9.215.2552,046
604.9.216.0/214.9.216.1 to 4.9.223.2544.9.223.2552,046
614.9.224.0/214.9.224.1 to 4.9.231.2544.9.231.2552,046
624.9.232.0/214.9.232.1 to 4.9.239.2544.9.239.2552,046
634.9.240.0/214.9.240.1 to 4.9.247.2544.9.247.2552,046
644.9.248.0/214.9.248.1 to 4.9.255.2544.9.255.2552,046
654.10.0.0/214.10.0.1 to 4.10.7.2544.10.7.2552,046
664.10.8.0/214.10.8.1 to 4.10.15.2544.10.15.2552,046
674.10.16.0/214.10.16.1 to 4.10.23.2544.10.23.2552,046
684.10.24.0/214.10.24.1 to 4.10.31.2544.10.31.2552,046
694.10.32.0/214.10.32.1 to 4.10.39.2544.10.39.2552,046
704.10.40.0/214.10.40.1 to 4.10.47.2544.10.47.2552,046
714.10.48.0/214.10.48.1 to 4.10.55.2544.10.55.2552,046
724.10.56.0/214.10.56.1 to 4.10.63.2544.10.63.2552,046
734.10.64.0/214.10.64.1 to 4.10.71.2544.10.71.2552,046
744.10.72.0/214.10.72.1 to 4.10.79.2544.10.79.2552,046
754.10.80.0/214.10.80.1 to 4.10.87.2544.10.87.2552,046
764.10.88.0/214.10.88.1 to 4.10.95.2544.10.95.2552,046
774.10.96.0/214.10.96.1 to 4.10.103.2544.10.103.2552,046
784.10.104.0/214.10.104.1 to 4.10.111.2544.10.111.2552,046
794.10.112.0/214.10.112.1 to 4.10.119.2544.10.119.2552,046
804.10.120.0/214.10.120.1 to 4.10.127.2544.10.127.2552,046
814.10.128.0/214.10.128.1 to 4.10.135.2544.10.135.2552,046
824.10.136.0/214.10.136.1 to 4.10.143.2544.10.143.2552,046
834.10.144.0/214.10.144.1 to 4.10.151.2544.10.151.2552,046
844.10.152.0/214.10.152.1 to 4.10.159.2544.10.159.2552,046
854.10.160.0/214.10.160.1 to 4.10.167.2544.10.167.2552,046
864.10.168.0/214.10.168.1 to 4.10.175.2544.10.175.2552,046
874.10.176.0/214.10.176.1 to 4.10.183.2544.10.183.2552,046
884.10.184.0/214.10.184.1 to 4.10.191.2544.10.191.2552,046
894.10.192.0/214.10.192.1 to 4.10.199.2544.10.199.2552,046
904.10.200.0/214.10.200.1 to 4.10.207.2544.10.207.2552,046
914.10.208.0/214.10.208.1 to 4.10.215.2544.10.215.2552,046
924.10.216.0/214.10.216.1 to 4.10.223.2544.10.223.2552,046
934.10.224.0/214.10.224.1 to 4.10.231.2544.10.231.2552,046
944.10.232.0/214.10.232.1 to 4.10.239.2544.10.239.2552,046
954.10.240.0/214.10.240.1 to 4.10.247.2544.10.247.2552,046
964.10.248.0/214.10.248.1 to 4.10.255.2544.10.255.2552,046
974.11.0.0/214.11.0.1 to 4.11.7.2544.11.7.2552,046
984.11.8.0/214.11.8.1 to 4.11.15.2544.11.15.2552,046
994.11.16.0/214.11.16.1 to 4.11.23.2544.11.23.2552,046
1004.11.24.0/214.11.24.1 to 4.11.31.2544.11.31.2552,046
1014.11.32.0/214.11.32.1 to 4.11.39.2544.11.39.2552,046
1024.11.40.0/214.11.40.1 to 4.11.47.2544.11.47.2552,046
1034.11.48.0/214.11.48.1 to 4.11.55.2544.11.55.2552,046
1044.11.56.0/214.11.56.1 to 4.11.63.2544.11.63.2552,046
1054.11.64.0/214.11.64.1 to 4.11.71.2544.11.71.2552,046
1064.11.72.0/214.11.72.1 to 4.11.79.2544.11.79.2552,046
1074.11.80.0/214.11.80.1 to 4.11.87.2544.11.87.2552,046
1084.11.88.0/214.11.88.1 to 4.11.95.2544.11.95.2552,046
1094.11.96.0/214.11.96.1 to 4.11.103.2544.11.103.2552,046
1104.11.104.0/214.11.104.1 to 4.11.111.2544.11.111.2552,046
1114.11.112.0/214.11.112.1 to 4.11.119.2544.11.119.2552,046
1124.11.120.0/214.11.120.1 to 4.11.127.2544.11.127.2552,046
1134.11.128.0/214.11.128.1 to 4.11.135.2544.11.135.2552,046
1144.11.136.0/214.11.136.1 to 4.11.143.2544.11.143.2552,046
1154.11.144.0/214.11.144.1 to 4.11.151.2544.11.151.2552,046
1164.11.152.0/214.11.152.1 to 4.11.159.2544.11.159.2552,046
1174.11.160.0/214.11.160.1 to 4.11.167.2544.11.167.2552,046
1184.11.168.0/214.11.168.1 to 4.11.175.2544.11.175.2552,046
1194.11.176.0/214.11.176.1 to 4.11.183.2544.11.183.2552,046
1204.11.184.0/214.11.184.1 to 4.11.191.2544.11.191.2552,046
1214.11.192.0/214.11.192.1 to 4.11.199.2544.11.199.2552,046
1224.11.200.0/214.11.200.1 to 4.11.207.2544.11.207.2552,046
1234.11.208.0/214.11.208.1 to 4.11.215.2544.11.215.2552,046
1244.11.216.0/214.11.216.1 to 4.11.223.2544.11.223.2552,046
1254.11.224.0/214.11.224.1 to 4.11.231.2544.11.231.2552,046
1264.11.232.0/214.11.232.1 to 4.11.239.2544.11.239.2552,046
1274.11.240.0/214.11.240.1 to 4.11.247.2544.11.247.2552,046
1284.11.248.0/214.11.248.1 to 4.11.255.2544.11.255.2552,046

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