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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.

Network11.124.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
11.124.0.0
Broadcast address
11.127.255.255
First usable
11.124.0.1
Last usable
11.127.255.254
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 0B7C0000 · Integer 192675840 to 192937983
Reverse DNS zones
124.11.in-addr.arpa
125.11.in-addr.arpa
126.11.in-addr.arpa
127.11.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
Address00001011.01111100.00000000.0000000011.124.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network00001011.01111100.00000000.0000000011.124.0.0
Broadcast00001011.01111111.11111111.1111111111.127.255.255
Split into smaller subnets/20
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

11.124.0.0/14 makes 64 subnets of /20.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
111.124.0.0/2011.124.0.1 to 11.124.15.25411.124.15.2554,094
211.124.16.0/2011.124.16.1 to 11.124.31.25411.124.31.2554,094
311.124.32.0/2011.124.32.1 to 11.124.47.25411.124.47.2554,094
411.124.48.0/2011.124.48.1 to 11.124.63.25411.124.63.2554,094
511.124.64.0/2011.124.64.1 to 11.124.79.25411.124.79.2554,094
611.124.80.0/2011.124.80.1 to 11.124.95.25411.124.95.2554,094
711.124.96.0/2011.124.96.1 to 11.124.111.25411.124.111.2554,094
811.124.112.0/2011.124.112.1 to 11.124.127.25411.124.127.2554,094
911.124.128.0/2011.124.128.1 to 11.124.143.25411.124.143.2554,094
1011.124.144.0/2011.124.144.1 to 11.124.159.25411.124.159.2554,094
1111.124.160.0/2011.124.160.1 to 11.124.175.25411.124.175.2554,094
1211.124.176.0/2011.124.176.1 to 11.124.191.25411.124.191.2554,094
1311.124.192.0/2011.124.192.1 to 11.124.207.25411.124.207.2554,094
1411.124.208.0/2011.124.208.1 to 11.124.223.25411.124.223.2554,094
1511.124.224.0/2011.124.224.1 to 11.124.239.25411.124.239.2554,094
1611.124.240.0/2011.124.240.1 to 11.124.255.25411.124.255.2554,094
1711.125.0.0/2011.125.0.1 to 11.125.15.25411.125.15.2554,094
1811.125.16.0/2011.125.16.1 to 11.125.31.25411.125.31.2554,094
1911.125.32.0/2011.125.32.1 to 11.125.47.25411.125.47.2554,094
2011.125.48.0/2011.125.48.1 to 11.125.63.25411.125.63.2554,094
2111.125.64.0/2011.125.64.1 to 11.125.79.25411.125.79.2554,094
2211.125.80.0/2011.125.80.1 to 11.125.95.25411.125.95.2554,094
2311.125.96.0/2011.125.96.1 to 11.125.111.25411.125.111.2554,094
2411.125.112.0/2011.125.112.1 to 11.125.127.25411.125.127.2554,094
2511.125.128.0/2011.125.128.1 to 11.125.143.25411.125.143.2554,094
2611.125.144.0/2011.125.144.1 to 11.125.159.25411.125.159.2554,094
2711.125.160.0/2011.125.160.1 to 11.125.175.25411.125.175.2554,094
2811.125.176.0/2011.125.176.1 to 11.125.191.25411.125.191.2554,094
2911.125.192.0/2011.125.192.1 to 11.125.207.25411.125.207.2554,094
3011.125.208.0/2011.125.208.1 to 11.125.223.25411.125.223.2554,094
3111.125.224.0/2011.125.224.1 to 11.125.239.25411.125.239.2554,094
3211.125.240.0/2011.125.240.1 to 11.125.255.25411.125.255.2554,094
3311.126.0.0/2011.126.0.1 to 11.126.15.25411.126.15.2554,094
3411.126.16.0/2011.126.16.1 to 11.126.31.25411.126.31.2554,094
3511.126.32.0/2011.126.32.1 to 11.126.47.25411.126.47.2554,094
3611.126.48.0/2011.126.48.1 to 11.126.63.25411.126.63.2554,094
3711.126.64.0/2011.126.64.1 to 11.126.79.25411.126.79.2554,094
3811.126.80.0/2011.126.80.1 to 11.126.95.25411.126.95.2554,094
3911.126.96.0/2011.126.96.1 to 11.126.111.25411.126.111.2554,094
4011.126.112.0/2011.126.112.1 to 11.126.127.25411.126.127.2554,094
4111.126.128.0/2011.126.128.1 to 11.126.143.25411.126.143.2554,094
4211.126.144.0/2011.126.144.1 to 11.126.159.25411.126.159.2554,094
4311.126.160.0/2011.126.160.1 to 11.126.175.25411.126.175.2554,094
4411.126.176.0/2011.126.176.1 to 11.126.191.25411.126.191.2554,094
4511.126.192.0/2011.126.192.1 to 11.126.207.25411.126.207.2554,094
4611.126.208.0/2011.126.208.1 to 11.126.223.25411.126.223.2554,094
4711.126.224.0/2011.126.224.1 to 11.126.239.25411.126.239.2554,094
4811.126.240.0/2011.126.240.1 to 11.126.255.25411.126.255.2554,094
4911.127.0.0/2011.127.0.1 to 11.127.15.25411.127.15.2554,094
5011.127.16.0/2011.127.16.1 to 11.127.31.25411.127.31.2554,094
5111.127.32.0/2011.127.32.1 to 11.127.47.25411.127.47.2554,094
5211.127.48.0/2011.127.48.1 to 11.127.63.25411.127.63.2554,094
5311.127.64.0/2011.127.64.1 to 11.127.79.25411.127.79.2554,094
5411.127.80.0/2011.127.80.1 to 11.127.95.25411.127.95.2554,094
5511.127.96.0/2011.127.96.1 to 11.127.111.25411.127.111.2554,094
5611.127.112.0/2011.127.112.1 to 11.127.127.25411.127.127.2554,094
5711.127.128.0/2011.127.128.1 to 11.127.143.25411.127.143.2554,094
5811.127.144.0/2011.127.144.1 to 11.127.159.25411.127.159.2554,094
5911.127.160.0/2011.127.160.1 to 11.127.175.25411.127.175.2554,094
6011.127.176.0/2011.127.176.1 to 11.127.191.25411.127.191.2554,094
6111.127.192.0/2011.127.192.1 to 11.127.207.25411.127.207.2554,094
6211.127.208.0/2011.127.208.1 to 11.127.223.25411.127.223.2554,094
6311.127.224.0/2011.127.224.1 to 11.127.239.25411.127.239.2554,094
6411.127.240.0/2011.127.240.1 to 11.127.255.25411.127.255.2554,094

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.