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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.

Network46.167.76.0/24
Usable hosts254
Subnet mask255.255.255.0
Addresses256
Network address
46.167.76.0
Broadcast address
46.167.76.255
First usable
46.167.76.1
Last usable
46.167.76.254
Usable hosts
254 (256 less the network and broadcast addresses)
Subnet mask
255.255.255.0
Wildcard mask
0.0.0.255 (Cisco ACLs, OSPF)
Prefix length
/24
Type
Public public
Old class
A (default /8)
As numbers
Hex 2EA74C00 · Integer 782715904 to 782716159
Reverse DNS zone
76.167.46.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101110.10100111.01001100..0000000046.167.76.0
Subnet mask11111111.11111111.11111111..00000000255.255.255.0
Network00101110.10100111.01001100..0000000046.167.76.0
Broadcast00101110.10100111.01001100..1111111146.167.76.255
Split into smaller subnets/30
/25 (2)/26 (4)/27 (8)/28 (16)/29 (32)/30 (64)/31 (128)/32 (256)

46.167.76.0/24 makes 64 subnets of /30.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
146.167.76.0/3046.167.76.1 to 46.167.76.246.167.76.32
246.167.76.4/3046.167.76.5 to 46.167.76.646.167.76.72
346.167.76.8/3046.167.76.9 to 46.167.76.1046.167.76.112
446.167.76.12/3046.167.76.13 to 46.167.76.1446.167.76.152
546.167.76.16/3046.167.76.17 to 46.167.76.1846.167.76.192
646.167.76.20/3046.167.76.21 to 46.167.76.2246.167.76.232
746.167.76.24/3046.167.76.25 to 46.167.76.2646.167.76.272
846.167.76.28/3046.167.76.29 to 46.167.76.3046.167.76.312
946.167.76.32/3046.167.76.33 to 46.167.76.3446.167.76.352
1046.167.76.36/3046.167.76.37 to 46.167.76.3846.167.76.392
1146.167.76.40/3046.167.76.41 to 46.167.76.4246.167.76.432
1246.167.76.44/3046.167.76.45 to 46.167.76.4646.167.76.472
1346.167.76.48/3046.167.76.49 to 46.167.76.5046.167.76.512
1446.167.76.52/3046.167.76.53 to 46.167.76.5446.167.76.552
1546.167.76.56/3046.167.76.57 to 46.167.76.5846.167.76.592
1646.167.76.60/3046.167.76.61 to 46.167.76.6246.167.76.632
1746.167.76.64/3046.167.76.65 to 46.167.76.6646.167.76.672
1846.167.76.68/3046.167.76.69 to 46.167.76.7046.167.76.712
1946.167.76.72/3046.167.76.73 to 46.167.76.7446.167.76.752
2046.167.76.76/3046.167.76.77 to 46.167.76.7846.167.76.792
2146.167.76.80/3046.167.76.81 to 46.167.76.8246.167.76.832
2246.167.76.84/3046.167.76.85 to 46.167.76.8646.167.76.872
2346.167.76.88/3046.167.76.89 to 46.167.76.9046.167.76.912
2446.167.76.92/3046.167.76.93 to 46.167.76.9446.167.76.952
2546.167.76.96/3046.167.76.97 to 46.167.76.9846.167.76.992
2646.167.76.100/3046.167.76.101 to 46.167.76.10246.167.76.1032
2746.167.76.104/3046.167.76.105 to 46.167.76.10646.167.76.1072
2846.167.76.108/3046.167.76.109 to 46.167.76.11046.167.76.1112
2946.167.76.112/3046.167.76.113 to 46.167.76.11446.167.76.1152
3046.167.76.116/3046.167.76.117 to 46.167.76.11846.167.76.1192
3146.167.76.120/3046.167.76.121 to 46.167.76.12246.167.76.1232
3246.167.76.124/3046.167.76.125 to 46.167.76.12646.167.76.1272
3346.167.76.128/3046.167.76.129 to 46.167.76.13046.167.76.1312
3446.167.76.132/3046.167.76.133 to 46.167.76.13446.167.76.1352
3546.167.76.136/3046.167.76.137 to 46.167.76.13846.167.76.1392
3646.167.76.140/3046.167.76.141 to 46.167.76.14246.167.76.1432
3746.167.76.144/3046.167.76.145 to 46.167.76.14646.167.76.1472
3846.167.76.148/3046.167.76.149 to 46.167.76.15046.167.76.1512
3946.167.76.152/3046.167.76.153 to 46.167.76.15446.167.76.1552
4046.167.76.156/3046.167.76.157 to 46.167.76.15846.167.76.1592
4146.167.76.160/3046.167.76.161 to 46.167.76.16246.167.76.1632
4246.167.76.164/3046.167.76.165 to 46.167.76.16646.167.76.1672
4346.167.76.168/3046.167.76.169 to 46.167.76.17046.167.76.1712
4446.167.76.172/3046.167.76.173 to 46.167.76.17446.167.76.1752
4546.167.76.176/3046.167.76.177 to 46.167.76.17846.167.76.1792
4646.167.76.180/3046.167.76.181 to 46.167.76.18246.167.76.1832
4746.167.76.184/3046.167.76.185 to 46.167.76.18646.167.76.1872
4846.167.76.188/3046.167.76.189 to 46.167.76.19046.167.76.1912
4946.167.76.192/3046.167.76.193 to 46.167.76.19446.167.76.1952
5046.167.76.196/3046.167.76.197 to 46.167.76.19846.167.76.1992
5146.167.76.200/3046.167.76.201 to 46.167.76.20246.167.76.2032
5246.167.76.204/3046.167.76.205 to 46.167.76.20646.167.76.2072
5346.167.76.208/3046.167.76.209 to 46.167.76.21046.167.76.2112
5446.167.76.212/3046.167.76.213 to 46.167.76.21446.167.76.2152
5546.167.76.216/3046.167.76.217 to 46.167.76.21846.167.76.2192
5646.167.76.220/3046.167.76.221 to 46.167.76.22246.167.76.2232
5746.167.76.224/3046.167.76.225 to 46.167.76.22646.167.76.2272
5846.167.76.228/3046.167.76.229 to 46.167.76.23046.167.76.2312
5946.167.76.232/3046.167.76.233 to 46.167.76.23446.167.76.2352
6046.167.76.236/3046.167.76.237 to 46.167.76.23846.167.76.2392
6146.167.76.240/3046.167.76.241 to 46.167.76.24246.167.76.2432
6246.167.76.244/3046.167.76.245 to 46.167.76.24646.167.76.2472
6346.167.76.248/3046.167.76.249 to 46.167.76.25046.167.76.2512
6446.167.76.252/3046.167.76.253 to 46.167.76.25446.167.76.2552

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.