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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.

Network46.167.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
46.167.0.0
Broadcast address
46.167.127.255
First usable
46.167.0.1
Last usable
46.167.127.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
Public public
Old class
A (default /8)
As numbers
Hex 2EA70000 · Integer 782696448 to 782729215
Reverse DNS zones
0.167.46.in-addr.arpa
1.167.46.in-addr.arpa
2.167.46.in-addr.arpa
3.167.46.in-addr.arpa
4.167.46.in-addr.arpa
5.167.46.in-addr.arpa
6.167.46.in-addr.arpa
7.167.46.in-addr.arpa
8.167.46.in-addr.arpa
9.167.46.in-addr.arpa
10.167.46.in-addr.arpa
11.167.46.in-addr.arpa
12.167.46.in-addr.arpa
13.167.46.in-addr.arpa
14.167.46.in-addr.arpa
15.167.46.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101110.10100111.00000000.0000000046.167.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network00101110.10100111.00000000.0000000046.167.0.0
Broadcast00101110.10100111.01111111.1111111146.167.127.255
Split into smaller subnets/24
/18 (2)/19 (4)/20 (8)/21 (16)/22 (32)/23 (64)/24 (128)/25 (256)/26 (512)/27 (1,024)/28 (2,048)/29 (4,096)

46.167.0.0/17 makes 128 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
146.167.0.0/2446.167.0.1 to 46.167.0.25446.167.0.255254
246.167.1.0/2446.167.1.1 to 46.167.1.25446.167.1.255254
346.167.2.0/2446.167.2.1 to 46.167.2.25446.167.2.255254
446.167.3.0/2446.167.3.1 to 46.167.3.25446.167.3.255254
546.167.4.0/2446.167.4.1 to 46.167.4.25446.167.4.255254
646.167.5.0/2446.167.5.1 to 46.167.5.25446.167.5.255254
746.167.6.0/2446.167.6.1 to 46.167.6.25446.167.6.255254
846.167.7.0/2446.167.7.1 to 46.167.7.25446.167.7.255254
946.167.8.0/2446.167.8.1 to 46.167.8.25446.167.8.255254
1046.167.9.0/2446.167.9.1 to 46.167.9.25446.167.9.255254
1146.167.10.0/2446.167.10.1 to 46.167.10.25446.167.10.255254
1246.167.11.0/2446.167.11.1 to 46.167.11.25446.167.11.255254
1346.167.12.0/2446.167.12.1 to 46.167.12.25446.167.12.255254
1446.167.13.0/2446.167.13.1 to 46.167.13.25446.167.13.255254
1546.167.14.0/2446.167.14.1 to 46.167.14.25446.167.14.255254
1646.167.15.0/2446.167.15.1 to 46.167.15.25446.167.15.255254
1746.167.16.0/2446.167.16.1 to 46.167.16.25446.167.16.255254
1846.167.17.0/2446.167.17.1 to 46.167.17.25446.167.17.255254
1946.167.18.0/2446.167.18.1 to 46.167.18.25446.167.18.255254
2046.167.19.0/2446.167.19.1 to 46.167.19.25446.167.19.255254
2146.167.20.0/2446.167.20.1 to 46.167.20.25446.167.20.255254
2246.167.21.0/2446.167.21.1 to 46.167.21.25446.167.21.255254
2346.167.22.0/2446.167.22.1 to 46.167.22.25446.167.22.255254
2446.167.23.0/2446.167.23.1 to 46.167.23.25446.167.23.255254
2546.167.24.0/2446.167.24.1 to 46.167.24.25446.167.24.255254
2646.167.25.0/2446.167.25.1 to 46.167.25.25446.167.25.255254
2746.167.26.0/2446.167.26.1 to 46.167.26.25446.167.26.255254
2846.167.27.0/2446.167.27.1 to 46.167.27.25446.167.27.255254
2946.167.28.0/2446.167.28.1 to 46.167.28.25446.167.28.255254
3046.167.29.0/2446.167.29.1 to 46.167.29.25446.167.29.255254
3146.167.30.0/2446.167.30.1 to 46.167.30.25446.167.30.255254
3246.167.31.0/2446.167.31.1 to 46.167.31.25446.167.31.255254
3346.167.32.0/2446.167.32.1 to 46.167.32.25446.167.32.255254
3446.167.33.0/2446.167.33.1 to 46.167.33.25446.167.33.255254
3546.167.34.0/2446.167.34.1 to 46.167.34.25446.167.34.255254
3646.167.35.0/2446.167.35.1 to 46.167.35.25446.167.35.255254
3746.167.36.0/2446.167.36.1 to 46.167.36.25446.167.36.255254
3846.167.37.0/2446.167.37.1 to 46.167.37.25446.167.37.255254
3946.167.38.0/2446.167.38.1 to 46.167.38.25446.167.38.255254
4046.167.39.0/2446.167.39.1 to 46.167.39.25446.167.39.255254
4146.167.40.0/2446.167.40.1 to 46.167.40.25446.167.40.255254
4246.167.41.0/2446.167.41.1 to 46.167.41.25446.167.41.255254
4346.167.42.0/2446.167.42.1 to 46.167.42.25446.167.42.255254
4446.167.43.0/2446.167.43.1 to 46.167.43.25446.167.43.255254
4546.167.44.0/2446.167.44.1 to 46.167.44.25446.167.44.255254
4646.167.45.0/2446.167.45.1 to 46.167.45.25446.167.45.255254
4746.167.46.0/2446.167.46.1 to 46.167.46.25446.167.46.255254
4846.167.47.0/2446.167.47.1 to 46.167.47.25446.167.47.255254
4946.167.48.0/2446.167.48.1 to 46.167.48.25446.167.48.255254
5046.167.49.0/2446.167.49.1 to 46.167.49.25446.167.49.255254
5146.167.50.0/2446.167.50.1 to 46.167.50.25446.167.50.255254
5246.167.51.0/2446.167.51.1 to 46.167.51.25446.167.51.255254
5346.167.52.0/2446.167.52.1 to 46.167.52.25446.167.52.255254
5446.167.53.0/2446.167.53.1 to 46.167.53.25446.167.53.255254
5546.167.54.0/2446.167.54.1 to 46.167.54.25446.167.54.255254
5646.167.55.0/2446.167.55.1 to 46.167.55.25446.167.55.255254
5746.167.56.0/2446.167.56.1 to 46.167.56.25446.167.56.255254
5846.167.57.0/2446.167.57.1 to 46.167.57.25446.167.57.255254
5946.167.58.0/2446.167.58.1 to 46.167.58.25446.167.58.255254
6046.167.59.0/2446.167.59.1 to 46.167.59.25446.167.59.255254
6146.167.60.0/2446.167.60.1 to 46.167.60.25446.167.60.255254
6246.167.61.0/2446.167.61.1 to 46.167.61.25446.167.61.255254
6346.167.62.0/2446.167.62.1 to 46.167.62.25446.167.62.255254
6446.167.63.0/2446.167.63.1 to 46.167.63.25446.167.63.255254
6546.167.64.0/2446.167.64.1 to 46.167.64.25446.167.64.255254
6646.167.65.0/2446.167.65.1 to 46.167.65.25446.167.65.255254
6746.167.66.0/2446.167.66.1 to 46.167.66.25446.167.66.255254
6846.167.67.0/2446.167.67.1 to 46.167.67.25446.167.67.255254
6946.167.68.0/2446.167.68.1 to 46.167.68.25446.167.68.255254
7046.167.69.0/2446.167.69.1 to 46.167.69.25446.167.69.255254
7146.167.70.0/2446.167.70.1 to 46.167.70.25446.167.70.255254
7246.167.71.0/2446.167.71.1 to 46.167.71.25446.167.71.255254
7346.167.72.0/2446.167.72.1 to 46.167.72.25446.167.72.255254
7446.167.73.0/2446.167.73.1 to 46.167.73.25446.167.73.255254
7546.167.74.0/2446.167.74.1 to 46.167.74.25446.167.74.255254
7646.167.75.0/2446.167.75.1 to 46.167.75.25446.167.75.255254
7746.167.76.0/2446.167.76.1 to 46.167.76.25446.167.76.255254
7846.167.77.0/2446.167.77.1 to 46.167.77.25446.167.77.255254
7946.167.78.0/2446.167.78.1 to 46.167.78.25446.167.78.255254
8046.167.79.0/2446.167.79.1 to 46.167.79.25446.167.79.255254
8146.167.80.0/2446.167.80.1 to 46.167.80.25446.167.80.255254
8246.167.81.0/2446.167.81.1 to 46.167.81.25446.167.81.255254
8346.167.82.0/2446.167.82.1 to 46.167.82.25446.167.82.255254
8446.167.83.0/2446.167.83.1 to 46.167.83.25446.167.83.255254
8546.167.84.0/2446.167.84.1 to 46.167.84.25446.167.84.255254
8646.167.85.0/2446.167.85.1 to 46.167.85.25446.167.85.255254
8746.167.86.0/2446.167.86.1 to 46.167.86.25446.167.86.255254
8846.167.87.0/2446.167.87.1 to 46.167.87.25446.167.87.255254
8946.167.88.0/2446.167.88.1 to 46.167.88.25446.167.88.255254
9046.167.89.0/2446.167.89.1 to 46.167.89.25446.167.89.255254
9146.167.90.0/2446.167.90.1 to 46.167.90.25446.167.90.255254
9246.167.91.0/2446.167.91.1 to 46.167.91.25446.167.91.255254
9346.167.92.0/2446.167.92.1 to 46.167.92.25446.167.92.255254
9446.167.93.0/2446.167.93.1 to 46.167.93.25446.167.93.255254
9546.167.94.0/2446.167.94.1 to 46.167.94.25446.167.94.255254
9646.167.95.0/2446.167.95.1 to 46.167.95.25446.167.95.255254
9746.167.96.0/2446.167.96.1 to 46.167.96.25446.167.96.255254
9846.167.97.0/2446.167.97.1 to 46.167.97.25446.167.97.255254
9946.167.98.0/2446.167.98.1 to 46.167.98.25446.167.98.255254
10046.167.99.0/2446.167.99.1 to 46.167.99.25446.167.99.255254
10146.167.100.0/2446.167.100.1 to 46.167.100.25446.167.100.255254
10246.167.101.0/2446.167.101.1 to 46.167.101.25446.167.101.255254
10346.167.102.0/2446.167.102.1 to 46.167.102.25446.167.102.255254
10446.167.103.0/2446.167.103.1 to 46.167.103.25446.167.103.255254
10546.167.104.0/2446.167.104.1 to 46.167.104.25446.167.104.255254
10646.167.105.0/2446.167.105.1 to 46.167.105.25446.167.105.255254
10746.167.106.0/2446.167.106.1 to 46.167.106.25446.167.106.255254
10846.167.107.0/2446.167.107.1 to 46.167.107.25446.167.107.255254
10946.167.108.0/2446.167.108.1 to 46.167.108.25446.167.108.255254
11046.167.109.0/2446.167.109.1 to 46.167.109.25446.167.109.255254
11146.167.110.0/2446.167.110.1 to 46.167.110.25446.167.110.255254
11246.167.111.0/2446.167.111.1 to 46.167.111.25446.167.111.255254
11346.167.112.0/2446.167.112.1 to 46.167.112.25446.167.112.255254
11446.167.113.0/2446.167.113.1 to 46.167.113.25446.167.113.255254
11546.167.114.0/2446.167.114.1 to 46.167.114.25446.167.114.255254
11646.167.115.0/2446.167.115.1 to 46.167.115.25446.167.115.255254
11746.167.116.0/2446.167.116.1 to 46.167.116.25446.167.116.255254
11846.167.117.0/2446.167.117.1 to 46.167.117.25446.167.117.255254
11946.167.118.0/2446.167.118.1 to 46.167.118.25446.167.118.255254
12046.167.119.0/2446.167.119.1 to 46.167.119.25446.167.119.255254
12146.167.120.0/2446.167.120.1 to 46.167.120.25446.167.120.255254
12246.167.121.0/2446.167.121.1 to 46.167.121.25446.167.121.255254
12346.167.122.0/2446.167.122.1 to 46.167.122.25446.167.122.255254
12446.167.123.0/2446.167.123.1 to 46.167.123.25446.167.123.255254
12546.167.124.0/2446.167.124.1 to 46.167.124.25446.167.124.255254
12646.167.125.0/2446.167.125.1 to 46.167.125.25446.167.125.255254
12746.167.126.0/2446.167.126.1 to 46.167.126.25446.167.126.255254
12846.167.127.0/2446.167.127.1 to 46.167.127.25446.167.127.255254

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.