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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.

Network49.167.24.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
49.167.24.0
Broadcast address
49.167.27.255
First usable
49.167.24.1
Last usable
49.167.27.254
Usable hosts
1,022 (1,024 less the network and broadcast addresses)
Subnet mask
255.255.252.0
Wildcard mask
0.0.3.255 (Cisco ACLs, OSPF)
Prefix length
/22
Type
Public public
Old class
A (default /8)
As numbers
Hex 31A71800 · Integer 833034240 to 833035263
Reverse DNS zones
24.167.49.in-addr.arpa
25.167.49.in-addr.arpa
26.167.49.in-addr.arpa
27.167.49.in-addr.arpa
/22 is not on a 8-bit boundary, so it takes 4 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00110001.10100111.00011000.0000000049.167.24.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network00110001.10100111.00011000.0000000049.167.24.0
Broadcast00110001.10100111.00011011.1111111149.167.27.255
Split into smaller subnets/29
/23 (2)/24 (4)/25 (8)/26 (16)/27 (32)/28 (64)/29 (128)/30 (256)/31 (512)/32 (1,024)

49.167.24.0/22 makes 128 subnets of /29.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
149.167.24.0/2949.167.24.1 to 49.167.24.649.167.24.76
249.167.24.8/2949.167.24.9 to 49.167.24.1449.167.24.156
349.167.24.16/2949.167.24.17 to 49.167.24.2249.167.24.236
449.167.24.24/2949.167.24.25 to 49.167.24.3049.167.24.316
549.167.24.32/2949.167.24.33 to 49.167.24.3849.167.24.396
649.167.24.40/2949.167.24.41 to 49.167.24.4649.167.24.476
749.167.24.48/2949.167.24.49 to 49.167.24.5449.167.24.556
849.167.24.56/2949.167.24.57 to 49.167.24.6249.167.24.636
949.167.24.64/2949.167.24.65 to 49.167.24.7049.167.24.716
1049.167.24.72/2949.167.24.73 to 49.167.24.7849.167.24.796
1149.167.24.80/2949.167.24.81 to 49.167.24.8649.167.24.876
1249.167.24.88/2949.167.24.89 to 49.167.24.9449.167.24.956
1349.167.24.96/2949.167.24.97 to 49.167.24.10249.167.24.1036
1449.167.24.104/2949.167.24.105 to 49.167.24.11049.167.24.1116
1549.167.24.112/2949.167.24.113 to 49.167.24.11849.167.24.1196
1649.167.24.120/2949.167.24.121 to 49.167.24.12649.167.24.1276
1749.167.24.128/2949.167.24.129 to 49.167.24.13449.167.24.1356
1849.167.24.136/2949.167.24.137 to 49.167.24.14249.167.24.1436
1949.167.24.144/2949.167.24.145 to 49.167.24.15049.167.24.1516
2049.167.24.152/2949.167.24.153 to 49.167.24.15849.167.24.1596
2149.167.24.160/2949.167.24.161 to 49.167.24.16649.167.24.1676
2249.167.24.168/2949.167.24.169 to 49.167.24.17449.167.24.1756
2349.167.24.176/2949.167.24.177 to 49.167.24.18249.167.24.1836
2449.167.24.184/2949.167.24.185 to 49.167.24.19049.167.24.1916
2549.167.24.192/2949.167.24.193 to 49.167.24.19849.167.24.1996
2649.167.24.200/2949.167.24.201 to 49.167.24.20649.167.24.2076
2749.167.24.208/2949.167.24.209 to 49.167.24.21449.167.24.2156
2849.167.24.216/2949.167.24.217 to 49.167.24.22249.167.24.2236
2949.167.24.224/2949.167.24.225 to 49.167.24.23049.167.24.2316
3049.167.24.232/2949.167.24.233 to 49.167.24.23849.167.24.2396
3149.167.24.240/2949.167.24.241 to 49.167.24.24649.167.24.2476
3249.167.24.248/2949.167.24.249 to 49.167.24.25449.167.24.2556
3349.167.25.0/2949.167.25.1 to 49.167.25.649.167.25.76
3449.167.25.8/2949.167.25.9 to 49.167.25.1449.167.25.156
3549.167.25.16/2949.167.25.17 to 49.167.25.2249.167.25.236
3649.167.25.24/2949.167.25.25 to 49.167.25.3049.167.25.316
3749.167.25.32/2949.167.25.33 to 49.167.25.3849.167.25.396
3849.167.25.40/2949.167.25.41 to 49.167.25.4649.167.25.476
3949.167.25.48/2949.167.25.49 to 49.167.25.5449.167.25.556
4049.167.25.56/2949.167.25.57 to 49.167.25.6249.167.25.636
4149.167.25.64/2949.167.25.65 to 49.167.25.7049.167.25.716
4249.167.25.72/2949.167.25.73 to 49.167.25.7849.167.25.796
4349.167.25.80/2949.167.25.81 to 49.167.25.8649.167.25.876
4449.167.25.88/2949.167.25.89 to 49.167.25.9449.167.25.956
4549.167.25.96/2949.167.25.97 to 49.167.25.10249.167.25.1036
4649.167.25.104/2949.167.25.105 to 49.167.25.11049.167.25.1116
4749.167.25.112/2949.167.25.113 to 49.167.25.11849.167.25.1196
4849.167.25.120/2949.167.25.121 to 49.167.25.12649.167.25.1276
4949.167.25.128/2949.167.25.129 to 49.167.25.13449.167.25.1356
5049.167.25.136/2949.167.25.137 to 49.167.25.14249.167.25.1436
5149.167.25.144/2949.167.25.145 to 49.167.25.15049.167.25.1516
5249.167.25.152/2949.167.25.153 to 49.167.25.15849.167.25.1596
5349.167.25.160/2949.167.25.161 to 49.167.25.16649.167.25.1676
5449.167.25.168/2949.167.25.169 to 49.167.25.17449.167.25.1756
5549.167.25.176/2949.167.25.177 to 49.167.25.18249.167.25.1836
5649.167.25.184/2949.167.25.185 to 49.167.25.19049.167.25.1916
5749.167.25.192/2949.167.25.193 to 49.167.25.19849.167.25.1996
5849.167.25.200/2949.167.25.201 to 49.167.25.20649.167.25.2076
5949.167.25.208/2949.167.25.209 to 49.167.25.21449.167.25.2156
6049.167.25.216/2949.167.25.217 to 49.167.25.22249.167.25.2236
6149.167.25.224/2949.167.25.225 to 49.167.25.23049.167.25.2316
6249.167.25.232/2949.167.25.233 to 49.167.25.23849.167.25.2396
6349.167.25.240/2949.167.25.241 to 49.167.25.24649.167.25.2476
6449.167.25.248/2949.167.25.249 to 49.167.25.25449.167.25.2556
6549.167.26.0/2949.167.26.1 to 49.167.26.649.167.26.76
6649.167.26.8/2949.167.26.9 to 49.167.26.1449.167.26.156
6749.167.26.16/2949.167.26.17 to 49.167.26.2249.167.26.236
6849.167.26.24/2949.167.26.25 to 49.167.26.3049.167.26.316
6949.167.26.32/2949.167.26.33 to 49.167.26.3849.167.26.396
7049.167.26.40/2949.167.26.41 to 49.167.26.4649.167.26.476
7149.167.26.48/2949.167.26.49 to 49.167.26.5449.167.26.556
7249.167.26.56/2949.167.26.57 to 49.167.26.6249.167.26.636
7349.167.26.64/2949.167.26.65 to 49.167.26.7049.167.26.716
7449.167.26.72/2949.167.26.73 to 49.167.26.7849.167.26.796
7549.167.26.80/2949.167.26.81 to 49.167.26.8649.167.26.876
7649.167.26.88/2949.167.26.89 to 49.167.26.9449.167.26.956
7749.167.26.96/2949.167.26.97 to 49.167.26.10249.167.26.1036
7849.167.26.104/2949.167.26.105 to 49.167.26.11049.167.26.1116
7949.167.26.112/2949.167.26.113 to 49.167.26.11849.167.26.1196
8049.167.26.120/2949.167.26.121 to 49.167.26.12649.167.26.1276
8149.167.26.128/2949.167.26.129 to 49.167.26.13449.167.26.1356
8249.167.26.136/2949.167.26.137 to 49.167.26.14249.167.26.1436
8349.167.26.144/2949.167.26.145 to 49.167.26.15049.167.26.1516
8449.167.26.152/2949.167.26.153 to 49.167.26.15849.167.26.1596
8549.167.26.160/2949.167.26.161 to 49.167.26.16649.167.26.1676
8649.167.26.168/2949.167.26.169 to 49.167.26.17449.167.26.1756
8749.167.26.176/2949.167.26.177 to 49.167.26.18249.167.26.1836
8849.167.26.184/2949.167.26.185 to 49.167.26.19049.167.26.1916
8949.167.26.192/2949.167.26.193 to 49.167.26.19849.167.26.1996
9049.167.26.200/2949.167.26.201 to 49.167.26.20649.167.26.2076
9149.167.26.208/2949.167.26.209 to 49.167.26.21449.167.26.2156
9249.167.26.216/2949.167.26.217 to 49.167.26.22249.167.26.2236
9349.167.26.224/2949.167.26.225 to 49.167.26.23049.167.26.2316
9449.167.26.232/2949.167.26.233 to 49.167.26.23849.167.26.2396
9549.167.26.240/2949.167.26.241 to 49.167.26.24649.167.26.2476
9649.167.26.248/2949.167.26.249 to 49.167.26.25449.167.26.2556
9749.167.27.0/2949.167.27.1 to 49.167.27.649.167.27.76
9849.167.27.8/2949.167.27.9 to 49.167.27.1449.167.27.156
9949.167.27.16/2949.167.27.17 to 49.167.27.2249.167.27.236
10049.167.27.24/2949.167.27.25 to 49.167.27.3049.167.27.316
10149.167.27.32/2949.167.27.33 to 49.167.27.3849.167.27.396
10249.167.27.40/2949.167.27.41 to 49.167.27.4649.167.27.476
10349.167.27.48/2949.167.27.49 to 49.167.27.5449.167.27.556
10449.167.27.56/2949.167.27.57 to 49.167.27.6249.167.27.636
10549.167.27.64/2949.167.27.65 to 49.167.27.7049.167.27.716
10649.167.27.72/2949.167.27.73 to 49.167.27.7849.167.27.796
10749.167.27.80/2949.167.27.81 to 49.167.27.8649.167.27.876
10849.167.27.88/2949.167.27.89 to 49.167.27.9449.167.27.956
10949.167.27.96/2949.167.27.97 to 49.167.27.10249.167.27.1036
11049.167.27.104/2949.167.27.105 to 49.167.27.11049.167.27.1116
11149.167.27.112/2949.167.27.113 to 49.167.27.11849.167.27.1196
11249.167.27.120/2949.167.27.121 to 49.167.27.12649.167.27.1276
11349.167.27.128/2949.167.27.129 to 49.167.27.13449.167.27.1356
11449.167.27.136/2949.167.27.137 to 49.167.27.14249.167.27.1436
11549.167.27.144/2949.167.27.145 to 49.167.27.15049.167.27.1516
11649.167.27.152/2949.167.27.153 to 49.167.27.15849.167.27.1596
11749.167.27.160/2949.167.27.161 to 49.167.27.16649.167.27.1676
11849.167.27.168/2949.167.27.169 to 49.167.27.17449.167.27.1756
11949.167.27.176/2949.167.27.177 to 49.167.27.18249.167.27.1836
12049.167.27.184/2949.167.27.185 to 49.167.27.19049.167.27.1916
12149.167.27.192/2949.167.27.193 to 49.167.27.19849.167.27.1996
12249.167.27.200/2949.167.27.201 to 49.167.27.20649.167.27.2076
12349.167.27.208/2949.167.27.209 to 49.167.27.21449.167.27.2156
12449.167.27.216/2949.167.27.217 to 49.167.27.22249.167.27.2236
12549.167.27.224/2949.167.27.225 to 49.167.27.23049.167.27.2316
12649.167.27.232/2949.167.27.233 to 49.167.27.23849.167.27.2396
12749.167.27.240/2949.167.27.241 to 49.167.27.24649.167.27.2476
12849.167.27.248/2949.167.27.249 to 49.167.27.25449.167.27.2556

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.