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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.

Network14.0.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
14.0.0.0
Broadcast address
14.7.255.255
First usable
14.0.0.1
Last usable
14.7.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
A (default /8)
As numbers
Hex 0E000000 · Integer 234881024 to 235405311
Reverse DNS zones
0.14.in-addr.arpa
1.14.in-addr.arpa
2.14.in-addr.arpa
3.14.in-addr.arpa
4.14.in-addr.arpa
5.14.in-addr.arpa
6.14.in-addr.arpa
7.14.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00001110.00000000.00000000.0000000014.0.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network00001110.00000000.00000000.0000000014.0.0.0
Broadcast00001110.00000111.11111111.1111111114.7.255.255
Split into smaller subnets/20
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

14.0.0.0/13 makes 128 subnets of /20.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
114.0.0.0/2014.0.0.1 to 14.0.15.25414.0.15.2554,094
214.0.16.0/2014.0.16.1 to 14.0.31.25414.0.31.2554,094
314.0.32.0/2014.0.32.1 to 14.0.47.25414.0.47.2554,094
414.0.48.0/2014.0.48.1 to 14.0.63.25414.0.63.2554,094
514.0.64.0/2014.0.64.1 to 14.0.79.25414.0.79.2554,094
614.0.80.0/2014.0.80.1 to 14.0.95.25414.0.95.2554,094
714.0.96.0/2014.0.96.1 to 14.0.111.25414.0.111.2554,094
814.0.112.0/2014.0.112.1 to 14.0.127.25414.0.127.2554,094
914.0.128.0/2014.0.128.1 to 14.0.143.25414.0.143.2554,094
1014.0.144.0/2014.0.144.1 to 14.0.159.25414.0.159.2554,094
1114.0.160.0/2014.0.160.1 to 14.0.175.25414.0.175.2554,094
1214.0.176.0/2014.0.176.1 to 14.0.191.25414.0.191.2554,094
1314.0.192.0/2014.0.192.1 to 14.0.207.25414.0.207.2554,094
1414.0.208.0/2014.0.208.1 to 14.0.223.25414.0.223.2554,094
1514.0.224.0/2014.0.224.1 to 14.0.239.25414.0.239.2554,094
1614.0.240.0/2014.0.240.1 to 14.0.255.25414.0.255.2554,094
1714.1.0.0/2014.1.0.1 to 14.1.15.25414.1.15.2554,094
1814.1.16.0/2014.1.16.1 to 14.1.31.25414.1.31.2554,094
1914.1.32.0/2014.1.32.1 to 14.1.47.25414.1.47.2554,094
2014.1.48.0/2014.1.48.1 to 14.1.63.25414.1.63.2554,094
2114.1.64.0/2014.1.64.1 to 14.1.79.25414.1.79.2554,094
2214.1.80.0/2014.1.80.1 to 14.1.95.25414.1.95.2554,094
2314.1.96.0/2014.1.96.1 to 14.1.111.25414.1.111.2554,094
2414.1.112.0/2014.1.112.1 to 14.1.127.25414.1.127.2554,094
2514.1.128.0/2014.1.128.1 to 14.1.143.25414.1.143.2554,094
2614.1.144.0/2014.1.144.1 to 14.1.159.25414.1.159.2554,094
2714.1.160.0/2014.1.160.1 to 14.1.175.25414.1.175.2554,094
2814.1.176.0/2014.1.176.1 to 14.1.191.25414.1.191.2554,094
2914.1.192.0/2014.1.192.1 to 14.1.207.25414.1.207.2554,094
3014.1.208.0/2014.1.208.1 to 14.1.223.25414.1.223.2554,094
3114.1.224.0/2014.1.224.1 to 14.1.239.25414.1.239.2554,094
3214.1.240.0/2014.1.240.1 to 14.1.255.25414.1.255.2554,094
3314.2.0.0/2014.2.0.1 to 14.2.15.25414.2.15.2554,094
3414.2.16.0/2014.2.16.1 to 14.2.31.25414.2.31.2554,094
3514.2.32.0/2014.2.32.1 to 14.2.47.25414.2.47.2554,094
3614.2.48.0/2014.2.48.1 to 14.2.63.25414.2.63.2554,094
3714.2.64.0/2014.2.64.1 to 14.2.79.25414.2.79.2554,094
3814.2.80.0/2014.2.80.1 to 14.2.95.25414.2.95.2554,094
3914.2.96.0/2014.2.96.1 to 14.2.111.25414.2.111.2554,094
4014.2.112.0/2014.2.112.1 to 14.2.127.25414.2.127.2554,094
4114.2.128.0/2014.2.128.1 to 14.2.143.25414.2.143.2554,094
4214.2.144.0/2014.2.144.1 to 14.2.159.25414.2.159.2554,094
4314.2.160.0/2014.2.160.1 to 14.2.175.25414.2.175.2554,094
4414.2.176.0/2014.2.176.1 to 14.2.191.25414.2.191.2554,094
4514.2.192.0/2014.2.192.1 to 14.2.207.25414.2.207.2554,094
4614.2.208.0/2014.2.208.1 to 14.2.223.25414.2.223.2554,094
4714.2.224.0/2014.2.224.1 to 14.2.239.25414.2.239.2554,094
4814.2.240.0/2014.2.240.1 to 14.2.255.25414.2.255.2554,094
4914.3.0.0/2014.3.0.1 to 14.3.15.25414.3.15.2554,094
5014.3.16.0/2014.3.16.1 to 14.3.31.25414.3.31.2554,094
5114.3.32.0/2014.3.32.1 to 14.3.47.25414.3.47.2554,094
5214.3.48.0/2014.3.48.1 to 14.3.63.25414.3.63.2554,094
5314.3.64.0/2014.3.64.1 to 14.3.79.25414.3.79.2554,094
5414.3.80.0/2014.3.80.1 to 14.3.95.25414.3.95.2554,094
5514.3.96.0/2014.3.96.1 to 14.3.111.25414.3.111.2554,094
5614.3.112.0/2014.3.112.1 to 14.3.127.25414.3.127.2554,094
5714.3.128.0/2014.3.128.1 to 14.3.143.25414.3.143.2554,094
5814.3.144.0/2014.3.144.1 to 14.3.159.25414.3.159.2554,094
5914.3.160.0/2014.3.160.1 to 14.3.175.25414.3.175.2554,094
6014.3.176.0/2014.3.176.1 to 14.3.191.25414.3.191.2554,094
6114.3.192.0/2014.3.192.1 to 14.3.207.25414.3.207.2554,094
6214.3.208.0/2014.3.208.1 to 14.3.223.25414.3.223.2554,094
6314.3.224.0/2014.3.224.1 to 14.3.239.25414.3.239.2554,094
6414.3.240.0/2014.3.240.1 to 14.3.255.25414.3.255.2554,094
6514.4.0.0/2014.4.0.1 to 14.4.15.25414.4.15.2554,094
6614.4.16.0/2014.4.16.1 to 14.4.31.25414.4.31.2554,094
6714.4.32.0/2014.4.32.1 to 14.4.47.25414.4.47.2554,094
6814.4.48.0/2014.4.48.1 to 14.4.63.25414.4.63.2554,094
6914.4.64.0/2014.4.64.1 to 14.4.79.25414.4.79.2554,094
7014.4.80.0/2014.4.80.1 to 14.4.95.25414.4.95.2554,094
7114.4.96.0/2014.4.96.1 to 14.4.111.25414.4.111.2554,094
7214.4.112.0/2014.4.112.1 to 14.4.127.25414.4.127.2554,094
7314.4.128.0/2014.4.128.1 to 14.4.143.25414.4.143.2554,094
7414.4.144.0/2014.4.144.1 to 14.4.159.25414.4.159.2554,094
7514.4.160.0/2014.4.160.1 to 14.4.175.25414.4.175.2554,094
7614.4.176.0/2014.4.176.1 to 14.4.191.25414.4.191.2554,094
7714.4.192.0/2014.4.192.1 to 14.4.207.25414.4.207.2554,094
7814.4.208.0/2014.4.208.1 to 14.4.223.25414.4.223.2554,094
7914.4.224.0/2014.4.224.1 to 14.4.239.25414.4.239.2554,094
8014.4.240.0/2014.4.240.1 to 14.4.255.25414.4.255.2554,094
8114.5.0.0/2014.5.0.1 to 14.5.15.25414.5.15.2554,094
8214.5.16.0/2014.5.16.1 to 14.5.31.25414.5.31.2554,094
8314.5.32.0/2014.5.32.1 to 14.5.47.25414.5.47.2554,094
8414.5.48.0/2014.5.48.1 to 14.5.63.25414.5.63.2554,094
8514.5.64.0/2014.5.64.1 to 14.5.79.25414.5.79.2554,094
8614.5.80.0/2014.5.80.1 to 14.5.95.25414.5.95.2554,094
8714.5.96.0/2014.5.96.1 to 14.5.111.25414.5.111.2554,094
8814.5.112.0/2014.5.112.1 to 14.5.127.25414.5.127.2554,094
8914.5.128.0/2014.5.128.1 to 14.5.143.25414.5.143.2554,094
9014.5.144.0/2014.5.144.1 to 14.5.159.25414.5.159.2554,094
9114.5.160.0/2014.5.160.1 to 14.5.175.25414.5.175.2554,094
9214.5.176.0/2014.5.176.1 to 14.5.191.25414.5.191.2554,094
9314.5.192.0/2014.5.192.1 to 14.5.207.25414.5.207.2554,094
9414.5.208.0/2014.5.208.1 to 14.5.223.25414.5.223.2554,094
9514.5.224.0/2014.5.224.1 to 14.5.239.25414.5.239.2554,094
9614.5.240.0/2014.5.240.1 to 14.5.255.25414.5.255.2554,094
9714.6.0.0/2014.6.0.1 to 14.6.15.25414.6.15.2554,094
9814.6.16.0/2014.6.16.1 to 14.6.31.25414.6.31.2554,094
9914.6.32.0/2014.6.32.1 to 14.6.47.25414.6.47.2554,094
10014.6.48.0/2014.6.48.1 to 14.6.63.25414.6.63.2554,094
10114.6.64.0/2014.6.64.1 to 14.6.79.25414.6.79.2554,094
10214.6.80.0/2014.6.80.1 to 14.6.95.25414.6.95.2554,094
10314.6.96.0/2014.6.96.1 to 14.6.111.25414.6.111.2554,094
10414.6.112.0/2014.6.112.1 to 14.6.127.25414.6.127.2554,094
10514.6.128.0/2014.6.128.1 to 14.6.143.25414.6.143.2554,094
10614.6.144.0/2014.6.144.1 to 14.6.159.25414.6.159.2554,094
10714.6.160.0/2014.6.160.1 to 14.6.175.25414.6.175.2554,094
10814.6.176.0/2014.6.176.1 to 14.6.191.25414.6.191.2554,094
10914.6.192.0/2014.6.192.1 to 14.6.207.25414.6.207.2554,094
11014.6.208.0/2014.6.208.1 to 14.6.223.25414.6.223.2554,094
11114.6.224.0/2014.6.224.1 to 14.6.239.25414.6.239.2554,094
11214.6.240.0/2014.6.240.1 to 14.6.255.25414.6.255.2554,094
11314.7.0.0/2014.7.0.1 to 14.7.15.25414.7.15.2554,094
11414.7.16.0/2014.7.16.1 to 14.7.31.25414.7.31.2554,094
11514.7.32.0/2014.7.32.1 to 14.7.47.25414.7.47.2554,094
11614.7.48.0/2014.7.48.1 to 14.7.63.25414.7.63.2554,094
11714.7.64.0/2014.7.64.1 to 14.7.79.25414.7.79.2554,094
11814.7.80.0/2014.7.80.1 to 14.7.95.25414.7.95.2554,094
11914.7.96.0/2014.7.96.1 to 14.7.111.25414.7.111.2554,094
12014.7.112.0/2014.7.112.1 to 14.7.127.25414.7.127.2554,094
12114.7.128.0/2014.7.128.1 to 14.7.143.25414.7.143.2554,094
12214.7.144.0/2014.7.144.1 to 14.7.159.25414.7.159.2554,094
12314.7.160.0/2014.7.160.1 to 14.7.175.25414.7.175.2554,094
12414.7.176.0/2014.7.176.1 to 14.7.191.25414.7.191.2554,094
12514.7.192.0/2014.7.192.1 to 14.7.207.25414.7.207.2554,094
12614.7.208.0/2014.7.208.1 to 14.7.223.25414.7.223.2554,094
12714.7.224.0/2014.7.224.1 to 14.7.239.25414.7.239.2554,094
12814.7.240.0/2014.7.240.1 to 14.7.255.25414.7.255.2554,094

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.