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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.

Network98.76.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
98.76.0.0
Broadcast address
98.79.255.255
First usable
98.76.0.1
Last usable
98.79.255.254
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 624C0000 · Integer 1649147904 to 1649410047
Reverse DNS zones
76.98.in-addr.arpa
77.98.in-addr.arpa
78.98.in-addr.arpa
79.98.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
Address01100010.01001100.00000000.0000000098.76.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01100010.01001100.00000000.0000000098.76.0.0
Broadcast01100010.01001111.11111111.1111111198.79.255.255
Split into smaller subnets/21
/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)

98.76.0.0/14 makes 128 subnets of /21.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
198.76.0.0/2198.76.0.1 to 98.76.7.25498.76.7.2552,046
298.76.8.0/2198.76.8.1 to 98.76.15.25498.76.15.2552,046
398.76.16.0/2198.76.16.1 to 98.76.23.25498.76.23.2552,046
498.76.24.0/2198.76.24.1 to 98.76.31.25498.76.31.2552,046
598.76.32.0/2198.76.32.1 to 98.76.39.25498.76.39.2552,046
698.76.40.0/2198.76.40.1 to 98.76.47.25498.76.47.2552,046
798.76.48.0/2198.76.48.1 to 98.76.55.25498.76.55.2552,046
898.76.56.0/2198.76.56.1 to 98.76.63.25498.76.63.2552,046
998.76.64.0/2198.76.64.1 to 98.76.71.25498.76.71.2552,046
1098.76.72.0/2198.76.72.1 to 98.76.79.25498.76.79.2552,046
1198.76.80.0/2198.76.80.1 to 98.76.87.25498.76.87.2552,046
1298.76.88.0/2198.76.88.1 to 98.76.95.25498.76.95.2552,046
1398.76.96.0/2198.76.96.1 to 98.76.103.25498.76.103.2552,046
1498.76.104.0/2198.76.104.1 to 98.76.111.25498.76.111.2552,046
1598.76.112.0/2198.76.112.1 to 98.76.119.25498.76.119.2552,046
1698.76.120.0/2198.76.120.1 to 98.76.127.25498.76.127.2552,046
1798.76.128.0/2198.76.128.1 to 98.76.135.25498.76.135.2552,046
1898.76.136.0/2198.76.136.1 to 98.76.143.25498.76.143.2552,046
1998.76.144.0/2198.76.144.1 to 98.76.151.25498.76.151.2552,046
2098.76.152.0/2198.76.152.1 to 98.76.159.25498.76.159.2552,046
2198.76.160.0/2198.76.160.1 to 98.76.167.25498.76.167.2552,046
2298.76.168.0/2198.76.168.1 to 98.76.175.25498.76.175.2552,046
2398.76.176.0/2198.76.176.1 to 98.76.183.25498.76.183.2552,046
2498.76.184.0/2198.76.184.1 to 98.76.191.25498.76.191.2552,046
2598.76.192.0/2198.76.192.1 to 98.76.199.25498.76.199.2552,046
2698.76.200.0/2198.76.200.1 to 98.76.207.25498.76.207.2552,046
2798.76.208.0/2198.76.208.1 to 98.76.215.25498.76.215.2552,046
2898.76.216.0/2198.76.216.1 to 98.76.223.25498.76.223.2552,046
2998.76.224.0/2198.76.224.1 to 98.76.231.25498.76.231.2552,046
3098.76.232.0/2198.76.232.1 to 98.76.239.25498.76.239.2552,046
3198.76.240.0/2198.76.240.1 to 98.76.247.25498.76.247.2552,046
3298.76.248.0/2198.76.248.1 to 98.76.255.25498.76.255.2552,046
3398.77.0.0/2198.77.0.1 to 98.77.7.25498.77.7.2552,046
3498.77.8.0/2198.77.8.1 to 98.77.15.25498.77.15.2552,046
3598.77.16.0/2198.77.16.1 to 98.77.23.25498.77.23.2552,046
3698.77.24.0/2198.77.24.1 to 98.77.31.25498.77.31.2552,046
3798.77.32.0/2198.77.32.1 to 98.77.39.25498.77.39.2552,046
3898.77.40.0/2198.77.40.1 to 98.77.47.25498.77.47.2552,046
3998.77.48.0/2198.77.48.1 to 98.77.55.25498.77.55.2552,046
4098.77.56.0/2198.77.56.1 to 98.77.63.25498.77.63.2552,046
4198.77.64.0/2198.77.64.1 to 98.77.71.25498.77.71.2552,046
4298.77.72.0/2198.77.72.1 to 98.77.79.25498.77.79.2552,046
4398.77.80.0/2198.77.80.1 to 98.77.87.25498.77.87.2552,046
4498.77.88.0/2198.77.88.1 to 98.77.95.25498.77.95.2552,046
4598.77.96.0/2198.77.96.1 to 98.77.103.25498.77.103.2552,046
4698.77.104.0/2198.77.104.1 to 98.77.111.25498.77.111.2552,046
4798.77.112.0/2198.77.112.1 to 98.77.119.25498.77.119.2552,046
4898.77.120.0/2198.77.120.1 to 98.77.127.25498.77.127.2552,046
4998.77.128.0/2198.77.128.1 to 98.77.135.25498.77.135.2552,046
5098.77.136.0/2198.77.136.1 to 98.77.143.25498.77.143.2552,046
5198.77.144.0/2198.77.144.1 to 98.77.151.25498.77.151.2552,046
5298.77.152.0/2198.77.152.1 to 98.77.159.25498.77.159.2552,046
5398.77.160.0/2198.77.160.1 to 98.77.167.25498.77.167.2552,046
5498.77.168.0/2198.77.168.1 to 98.77.175.25498.77.175.2552,046
5598.77.176.0/2198.77.176.1 to 98.77.183.25498.77.183.2552,046
5698.77.184.0/2198.77.184.1 to 98.77.191.25498.77.191.2552,046
5798.77.192.0/2198.77.192.1 to 98.77.199.25498.77.199.2552,046
5898.77.200.0/2198.77.200.1 to 98.77.207.25498.77.207.2552,046
5998.77.208.0/2198.77.208.1 to 98.77.215.25498.77.215.2552,046
6098.77.216.0/2198.77.216.1 to 98.77.223.25498.77.223.2552,046
6198.77.224.0/2198.77.224.1 to 98.77.231.25498.77.231.2552,046
6298.77.232.0/2198.77.232.1 to 98.77.239.25498.77.239.2552,046
6398.77.240.0/2198.77.240.1 to 98.77.247.25498.77.247.2552,046
6498.77.248.0/2198.77.248.1 to 98.77.255.25498.77.255.2552,046
6598.78.0.0/2198.78.0.1 to 98.78.7.25498.78.7.2552,046
6698.78.8.0/2198.78.8.1 to 98.78.15.25498.78.15.2552,046
6798.78.16.0/2198.78.16.1 to 98.78.23.25498.78.23.2552,046
6898.78.24.0/2198.78.24.1 to 98.78.31.25498.78.31.2552,046
6998.78.32.0/2198.78.32.1 to 98.78.39.25498.78.39.2552,046
7098.78.40.0/2198.78.40.1 to 98.78.47.25498.78.47.2552,046
7198.78.48.0/2198.78.48.1 to 98.78.55.25498.78.55.2552,046
7298.78.56.0/2198.78.56.1 to 98.78.63.25498.78.63.2552,046
7398.78.64.0/2198.78.64.1 to 98.78.71.25498.78.71.2552,046
7498.78.72.0/2198.78.72.1 to 98.78.79.25498.78.79.2552,046
7598.78.80.0/2198.78.80.1 to 98.78.87.25498.78.87.2552,046
7698.78.88.0/2198.78.88.1 to 98.78.95.25498.78.95.2552,046
7798.78.96.0/2198.78.96.1 to 98.78.103.25498.78.103.2552,046
7898.78.104.0/2198.78.104.1 to 98.78.111.25498.78.111.2552,046
7998.78.112.0/2198.78.112.1 to 98.78.119.25498.78.119.2552,046
8098.78.120.0/2198.78.120.1 to 98.78.127.25498.78.127.2552,046
8198.78.128.0/2198.78.128.1 to 98.78.135.25498.78.135.2552,046
8298.78.136.0/2198.78.136.1 to 98.78.143.25498.78.143.2552,046
8398.78.144.0/2198.78.144.1 to 98.78.151.25498.78.151.2552,046
8498.78.152.0/2198.78.152.1 to 98.78.159.25498.78.159.2552,046
8598.78.160.0/2198.78.160.1 to 98.78.167.25498.78.167.2552,046
8698.78.168.0/2198.78.168.1 to 98.78.175.25498.78.175.2552,046
8798.78.176.0/2198.78.176.1 to 98.78.183.25498.78.183.2552,046
8898.78.184.0/2198.78.184.1 to 98.78.191.25498.78.191.2552,046
8998.78.192.0/2198.78.192.1 to 98.78.199.25498.78.199.2552,046
9098.78.200.0/2198.78.200.1 to 98.78.207.25498.78.207.2552,046
9198.78.208.0/2198.78.208.1 to 98.78.215.25498.78.215.2552,046
9298.78.216.0/2198.78.216.1 to 98.78.223.25498.78.223.2552,046
9398.78.224.0/2198.78.224.1 to 98.78.231.25498.78.231.2552,046
9498.78.232.0/2198.78.232.1 to 98.78.239.25498.78.239.2552,046
9598.78.240.0/2198.78.240.1 to 98.78.247.25498.78.247.2552,046
9698.78.248.0/2198.78.248.1 to 98.78.255.25498.78.255.2552,046
9798.79.0.0/2198.79.0.1 to 98.79.7.25498.79.7.2552,046
9898.79.8.0/2198.79.8.1 to 98.79.15.25498.79.15.2552,046
9998.79.16.0/2198.79.16.1 to 98.79.23.25498.79.23.2552,046
10098.79.24.0/2198.79.24.1 to 98.79.31.25498.79.31.2552,046
10198.79.32.0/2198.79.32.1 to 98.79.39.25498.79.39.2552,046
10298.79.40.0/2198.79.40.1 to 98.79.47.25498.79.47.2552,046
10398.79.48.0/2198.79.48.1 to 98.79.55.25498.79.55.2552,046
10498.79.56.0/2198.79.56.1 to 98.79.63.25498.79.63.2552,046
10598.79.64.0/2198.79.64.1 to 98.79.71.25498.79.71.2552,046
10698.79.72.0/2198.79.72.1 to 98.79.79.25498.79.79.2552,046
10798.79.80.0/2198.79.80.1 to 98.79.87.25498.79.87.2552,046
10898.79.88.0/2198.79.88.1 to 98.79.95.25498.79.95.2552,046
10998.79.96.0/2198.79.96.1 to 98.79.103.25498.79.103.2552,046
11098.79.104.0/2198.79.104.1 to 98.79.111.25498.79.111.2552,046
11198.79.112.0/2198.79.112.1 to 98.79.119.25498.79.119.2552,046
11298.79.120.0/2198.79.120.1 to 98.79.127.25498.79.127.2552,046
11398.79.128.0/2198.79.128.1 to 98.79.135.25498.79.135.2552,046
11498.79.136.0/2198.79.136.1 to 98.79.143.25498.79.143.2552,046
11598.79.144.0/2198.79.144.1 to 98.79.151.25498.79.151.2552,046
11698.79.152.0/2198.79.152.1 to 98.79.159.25498.79.159.2552,046
11798.79.160.0/2198.79.160.1 to 98.79.167.25498.79.167.2552,046
11898.79.168.0/2198.79.168.1 to 98.79.175.25498.79.175.2552,046
11998.79.176.0/2198.79.176.1 to 98.79.183.25498.79.183.2552,046
12098.79.184.0/2198.79.184.1 to 98.79.191.25498.79.191.2552,046
12198.79.192.0/2198.79.192.1 to 98.79.199.25498.79.199.2552,046
12298.79.200.0/2198.79.200.1 to 98.79.207.25498.79.207.2552,046
12398.79.208.0/2198.79.208.1 to 98.79.215.25498.79.215.2552,046
12498.79.216.0/2198.79.216.1 to 98.79.223.25498.79.223.2552,046
12598.79.224.0/2198.79.224.1 to 98.79.231.25498.79.231.2552,046
12698.79.232.0/2198.79.232.1 to 98.79.239.25498.79.239.2552,046
12798.79.240.0/2198.79.240.1 to 98.79.247.25498.79.247.2552,046
12898.79.248.0/2198.79.248.1 to 98.79.255.25498.79.255.2552,046

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

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.