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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.

Network98.48.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
98.48.0.0
Broadcast address
98.55.255.255
First usable
98.48.0.1
Last usable
98.55.255.254
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 62300000 · Integer 1647312896 to 1647837183
Reverse DNS zones
48.98.in-addr.arpa
49.98.in-addr.arpa
50.98.in-addr.arpa
51.98.in-addr.arpa
52.98.in-addr.arpa
53.98.in-addr.arpa
54.98.in-addr.arpa
55.98.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
Address01100010.00110000.00000000.0000000098.48.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01100010.00110000.00000000.0000000098.48.0.0
Broadcast01100010.00110111.11111111.1111111198.55.255.255
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)

98.48.0.0/13 makes 128 subnets of /20.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
198.48.0.0/2098.48.0.1 to 98.48.15.25498.48.15.2554,094
298.48.16.0/2098.48.16.1 to 98.48.31.25498.48.31.2554,094
398.48.32.0/2098.48.32.1 to 98.48.47.25498.48.47.2554,094
498.48.48.0/2098.48.48.1 to 98.48.63.25498.48.63.2554,094
598.48.64.0/2098.48.64.1 to 98.48.79.25498.48.79.2554,094
698.48.80.0/2098.48.80.1 to 98.48.95.25498.48.95.2554,094
798.48.96.0/2098.48.96.1 to 98.48.111.25498.48.111.2554,094
898.48.112.0/2098.48.112.1 to 98.48.127.25498.48.127.2554,094
998.48.128.0/2098.48.128.1 to 98.48.143.25498.48.143.2554,094
1098.48.144.0/2098.48.144.1 to 98.48.159.25498.48.159.2554,094
1198.48.160.0/2098.48.160.1 to 98.48.175.25498.48.175.2554,094
1298.48.176.0/2098.48.176.1 to 98.48.191.25498.48.191.2554,094
1398.48.192.0/2098.48.192.1 to 98.48.207.25498.48.207.2554,094
1498.48.208.0/2098.48.208.1 to 98.48.223.25498.48.223.2554,094
1598.48.224.0/2098.48.224.1 to 98.48.239.25498.48.239.2554,094
1698.48.240.0/2098.48.240.1 to 98.48.255.25498.48.255.2554,094
1798.49.0.0/2098.49.0.1 to 98.49.15.25498.49.15.2554,094
1898.49.16.0/2098.49.16.1 to 98.49.31.25498.49.31.2554,094
1998.49.32.0/2098.49.32.1 to 98.49.47.25498.49.47.2554,094
2098.49.48.0/2098.49.48.1 to 98.49.63.25498.49.63.2554,094
2198.49.64.0/2098.49.64.1 to 98.49.79.25498.49.79.2554,094
2298.49.80.0/2098.49.80.1 to 98.49.95.25498.49.95.2554,094
2398.49.96.0/2098.49.96.1 to 98.49.111.25498.49.111.2554,094
2498.49.112.0/2098.49.112.1 to 98.49.127.25498.49.127.2554,094
2598.49.128.0/2098.49.128.1 to 98.49.143.25498.49.143.2554,094
2698.49.144.0/2098.49.144.1 to 98.49.159.25498.49.159.2554,094
2798.49.160.0/2098.49.160.1 to 98.49.175.25498.49.175.2554,094
2898.49.176.0/2098.49.176.1 to 98.49.191.25498.49.191.2554,094
2998.49.192.0/2098.49.192.1 to 98.49.207.25498.49.207.2554,094
3098.49.208.0/2098.49.208.1 to 98.49.223.25498.49.223.2554,094
3198.49.224.0/2098.49.224.1 to 98.49.239.25498.49.239.2554,094
3298.49.240.0/2098.49.240.1 to 98.49.255.25498.49.255.2554,094
3398.50.0.0/2098.50.0.1 to 98.50.15.25498.50.15.2554,094
3498.50.16.0/2098.50.16.1 to 98.50.31.25498.50.31.2554,094
3598.50.32.0/2098.50.32.1 to 98.50.47.25498.50.47.2554,094
3698.50.48.0/2098.50.48.1 to 98.50.63.25498.50.63.2554,094
3798.50.64.0/2098.50.64.1 to 98.50.79.25498.50.79.2554,094
3898.50.80.0/2098.50.80.1 to 98.50.95.25498.50.95.2554,094
3998.50.96.0/2098.50.96.1 to 98.50.111.25498.50.111.2554,094
4098.50.112.0/2098.50.112.1 to 98.50.127.25498.50.127.2554,094
4198.50.128.0/2098.50.128.1 to 98.50.143.25498.50.143.2554,094
4298.50.144.0/2098.50.144.1 to 98.50.159.25498.50.159.2554,094
4398.50.160.0/2098.50.160.1 to 98.50.175.25498.50.175.2554,094
4498.50.176.0/2098.50.176.1 to 98.50.191.25498.50.191.2554,094
4598.50.192.0/2098.50.192.1 to 98.50.207.25498.50.207.2554,094
4698.50.208.0/2098.50.208.1 to 98.50.223.25498.50.223.2554,094
4798.50.224.0/2098.50.224.1 to 98.50.239.25498.50.239.2554,094
4898.50.240.0/2098.50.240.1 to 98.50.255.25498.50.255.2554,094
4998.51.0.0/2098.51.0.1 to 98.51.15.25498.51.15.2554,094
5098.51.16.0/2098.51.16.1 to 98.51.31.25498.51.31.2554,094
5198.51.32.0/2098.51.32.1 to 98.51.47.25498.51.47.2554,094
5298.51.48.0/2098.51.48.1 to 98.51.63.25498.51.63.2554,094
5398.51.64.0/2098.51.64.1 to 98.51.79.25498.51.79.2554,094
5498.51.80.0/2098.51.80.1 to 98.51.95.25498.51.95.2554,094
5598.51.96.0/2098.51.96.1 to 98.51.111.25498.51.111.2554,094
5698.51.112.0/2098.51.112.1 to 98.51.127.25498.51.127.2554,094
5798.51.128.0/2098.51.128.1 to 98.51.143.25498.51.143.2554,094
5898.51.144.0/2098.51.144.1 to 98.51.159.25498.51.159.2554,094
5998.51.160.0/2098.51.160.1 to 98.51.175.25498.51.175.2554,094
6098.51.176.0/2098.51.176.1 to 98.51.191.25498.51.191.2554,094
6198.51.192.0/2098.51.192.1 to 98.51.207.25498.51.207.2554,094
6298.51.208.0/2098.51.208.1 to 98.51.223.25498.51.223.2554,094
6398.51.224.0/2098.51.224.1 to 98.51.239.25498.51.239.2554,094
6498.51.240.0/2098.51.240.1 to 98.51.255.25498.51.255.2554,094
6598.52.0.0/2098.52.0.1 to 98.52.15.25498.52.15.2554,094
6698.52.16.0/2098.52.16.1 to 98.52.31.25498.52.31.2554,094
6798.52.32.0/2098.52.32.1 to 98.52.47.25498.52.47.2554,094
6898.52.48.0/2098.52.48.1 to 98.52.63.25498.52.63.2554,094
6998.52.64.0/2098.52.64.1 to 98.52.79.25498.52.79.2554,094
7098.52.80.0/2098.52.80.1 to 98.52.95.25498.52.95.2554,094
7198.52.96.0/2098.52.96.1 to 98.52.111.25498.52.111.2554,094
7298.52.112.0/2098.52.112.1 to 98.52.127.25498.52.127.2554,094
7398.52.128.0/2098.52.128.1 to 98.52.143.25498.52.143.2554,094
7498.52.144.0/2098.52.144.1 to 98.52.159.25498.52.159.2554,094
7598.52.160.0/2098.52.160.1 to 98.52.175.25498.52.175.2554,094
7698.52.176.0/2098.52.176.1 to 98.52.191.25498.52.191.2554,094
7798.52.192.0/2098.52.192.1 to 98.52.207.25498.52.207.2554,094
7898.52.208.0/2098.52.208.1 to 98.52.223.25498.52.223.2554,094
7998.52.224.0/2098.52.224.1 to 98.52.239.25498.52.239.2554,094
8098.52.240.0/2098.52.240.1 to 98.52.255.25498.52.255.2554,094
8198.53.0.0/2098.53.0.1 to 98.53.15.25498.53.15.2554,094
8298.53.16.0/2098.53.16.1 to 98.53.31.25498.53.31.2554,094
8398.53.32.0/2098.53.32.1 to 98.53.47.25498.53.47.2554,094
8498.53.48.0/2098.53.48.1 to 98.53.63.25498.53.63.2554,094
8598.53.64.0/2098.53.64.1 to 98.53.79.25498.53.79.2554,094
8698.53.80.0/2098.53.80.1 to 98.53.95.25498.53.95.2554,094
8798.53.96.0/2098.53.96.1 to 98.53.111.25498.53.111.2554,094
8898.53.112.0/2098.53.112.1 to 98.53.127.25498.53.127.2554,094
8998.53.128.0/2098.53.128.1 to 98.53.143.25498.53.143.2554,094
9098.53.144.0/2098.53.144.1 to 98.53.159.25498.53.159.2554,094
9198.53.160.0/2098.53.160.1 to 98.53.175.25498.53.175.2554,094
9298.53.176.0/2098.53.176.1 to 98.53.191.25498.53.191.2554,094
9398.53.192.0/2098.53.192.1 to 98.53.207.25498.53.207.2554,094
9498.53.208.0/2098.53.208.1 to 98.53.223.25498.53.223.2554,094
9598.53.224.0/2098.53.224.1 to 98.53.239.25498.53.239.2554,094
9698.53.240.0/2098.53.240.1 to 98.53.255.25498.53.255.2554,094
9798.54.0.0/2098.54.0.1 to 98.54.15.25498.54.15.2554,094
9898.54.16.0/2098.54.16.1 to 98.54.31.25498.54.31.2554,094
9998.54.32.0/2098.54.32.1 to 98.54.47.25498.54.47.2554,094
10098.54.48.0/2098.54.48.1 to 98.54.63.25498.54.63.2554,094
10198.54.64.0/2098.54.64.1 to 98.54.79.25498.54.79.2554,094
10298.54.80.0/2098.54.80.1 to 98.54.95.25498.54.95.2554,094
10398.54.96.0/2098.54.96.1 to 98.54.111.25498.54.111.2554,094
10498.54.112.0/2098.54.112.1 to 98.54.127.25498.54.127.2554,094
10598.54.128.0/2098.54.128.1 to 98.54.143.25498.54.143.2554,094
10698.54.144.0/2098.54.144.1 to 98.54.159.25498.54.159.2554,094
10798.54.160.0/2098.54.160.1 to 98.54.175.25498.54.175.2554,094
10898.54.176.0/2098.54.176.1 to 98.54.191.25498.54.191.2554,094
10998.54.192.0/2098.54.192.1 to 98.54.207.25498.54.207.2554,094
11098.54.208.0/2098.54.208.1 to 98.54.223.25498.54.223.2554,094
11198.54.224.0/2098.54.224.1 to 98.54.239.25498.54.239.2554,094
11298.54.240.0/2098.54.240.1 to 98.54.255.25498.54.255.2554,094
11398.55.0.0/2098.55.0.1 to 98.55.15.25498.55.15.2554,094
11498.55.16.0/2098.55.16.1 to 98.55.31.25498.55.31.2554,094
11598.55.32.0/2098.55.32.1 to 98.55.47.25498.55.47.2554,094
11698.55.48.0/2098.55.48.1 to 98.55.63.25498.55.63.2554,094
11798.55.64.0/2098.55.64.1 to 98.55.79.25498.55.79.2554,094
11898.55.80.0/2098.55.80.1 to 98.55.95.25498.55.95.2554,094
11998.55.96.0/2098.55.96.1 to 98.55.111.25498.55.111.2554,094
12098.55.112.0/2098.55.112.1 to 98.55.127.25498.55.127.2554,094
12198.55.128.0/2098.55.128.1 to 98.55.143.25498.55.143.2554,094
12298.55.144.0/2098.55.144.1 to 98.55.159.25498.55.159.2554,094
12398.55.160.0/2098.55.160.1 to 98.55.175.25498.55.175.2554,094
12498.55.176.0/2098.55.176.1 to 98.55.191.25498.55.191.2554,094
12598.55.192.0/2098.55.192.1 to 98.55.207.25498.55.207.2554,094
12698.55.208.0/2098.55.208.1 to 98.55.223.25498.55.223.2554,094
12798.55.224.0/2098.55.224.1 to 98.55.239.25498.55.239.2554,094
12898.55.240.0/2098.55.240.1 to 98.55.255.25498.55.255.2554,094

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.