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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.

Network32.167.232.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
32.167.232.0
Broadcast address
32.167.235.255
First usable
32.167.232.1
Last usable
32.167.235.254
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 20A7E800 · Integer 547874816 to 547875839
Reverse DNS zones
232.167.32.in-addr.arpa
233.167.32.in-addr.arpa
234.167.32.in-addr.arpa
235.167.32.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
Address00100000.10100111.11101000.0000000032.167.232.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network00100000.10100111.11101000.0000000032.167.232.0
Broadcast00100000.10100111.11101011.1111111132.167.235.255
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)

32.167.232.0/22 makes 128 subnets of /29.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
132.167.232.0/2932.167.232.1 to 32.167.232.632.167.232.76
232.167.232.8/2932.167.232.9 to 32.167.232.1432.167.232.156
332.167.232.16/2932.167.232.17 to 32.167.232.2232.167.232.236
432.167.232.24/2932.167.232.25 to 32.167.232.3032.167.232.316
532.167.232.32/2932.167.232.33 to 32.167.232.3832.167.232.396
632.167.232.40/2932.167.232.41 to 32.167.232.4632.167.232.476
732.167.232.48/2932.167.232.49 to 32.167.232.5432.167.232.556
832.167.232.56/2932.167.232.57 to 32.167.232.6232.167.232.636
932.167.232.64/2932.167.232.65 to 32.167.232.7032.167.232.716
1032.167.232.72/2932.167.232.73 to 32.167.232.7832.167.232.796
1132.167.232.80/2932.167.232.81 to 32.167.232.8632.167.232.876
1232.167.232.88/2932.167.232.89 to 32.167.232.9432.167.232.956
1332.167.232.96/2932.167.232.97 to 32.167.232.10232.167.232.1036
1432.167.232.104/2932.167.232.105 to 32.167.232.11032.167.232.1116
1532.167.232.112/2932.167.232.113 to 32.167.232.11832.167.232.1196
1632.167.232.120/2932.167.232.121 to 32.167.232.12632.167.232.1276
1732.167.232.128/2932.167.232.129 to 32.167.232.13432.167.232.1356
1832.167.232.136/2932.167.232.137 to 32.167.232.14232.167.232.1436
1932.167.232.144/2932.167.232.145 to 32.167.232.15032.167.232.1516
2032.167.232.152/2932.167.232.153 to 32.167.232.15832.167.232.1596
2132.167.232.160/2932.167.232.161 to 32.167.232.16632.167.232.1676
2232.167.232.168/2932.167.232.169 to 32.167.232.17432.167.232.1756
2332.167.232.176/2932.167.232.177 to 32.167.232.18232.167.232.1836
2432.167.232.184/2932.167.232.185 to 32.167.232.19032.167.232.1916
2532.167.232.192/2932.167.232.193 to 32.167.232.19832.167.232.1996
2632.167.232.200/2932.167.232.201 to 32.167.232.20632.167.232.2076
2732.167.232.208/2932.167.232.209 to 32.167.232.21432.167.232.2156
2832.167.232.216/2932.167.232.217 to 32.167.232.22232.167.232.2236
2932.167.232.224/2932.167.232.225 to 32.167.232.23032.167.232.2316
3032.167.232.232/2932.167.232.233 to 32.167.232.23832.167.232.2396
3132.167.232.240/2932.167.232.241 to 32.167.232.24632.167.232.2476
3232.167.232.248/2932.167.232.249 to 32.167.232.25432.167.232.2556
3332.167.233.0/2932.167.233.1 to 32.167.233.632.167.233.76
3432.167.233.8/2932.167.233.9 to 32.167.233.1432.167.233.156
3532.167.233.16/2932.167.233.17 to 32.167.233.2232.167.233.236
3632.167.233.24/2932.167.233.25 to 32.167.233.3032.167.233.316
3732.167.233.32/2932.167.233.33 to 32.167.233.3832.167.233.396
3832.167.233.40/2932.167.233.41 to 32.167.233.4632.167.233.476
3932.167.233.48/2932.167.233.49 to 32.167.233.5432.167.233.556
4032.167.233.56/2932.167.233.57 to 32.167.233.6232.167.233.636
4132.167.233.64/2932.167.233.65 to 32.167.233.7032.167.233.716
4232.167.233.72/2932.167.233.73 to 32.167.233.7832.167.233.796
4332.167.233.80/2932.167.233.81 to 32.167.233.8632.167.233.876
4432.167.233.88/2932.167.233.89 to 32.167.233.9432.167.233.956
4532.167.233.96/2932.167.233.97 to 32.167.233.10232.167.233.1036
4632.167.233.104/2932.167.233.105 to 32.167.233.11032.167.233.1116
4732.167.233.112/2932.167.233.113 to 32.167.233.11832.167.233.1196
4832.167.233.120/2932.167.233.121 to 32.167.233.12632.167.233.1276
4932.167.233.128/2932.167.233.129 to 32.167.233.13432.167.233.1356
5032.167.233.136/2932.167.233.137 to 32.167.233.14232.167.233.1436
5132.167.233.144/2932.167.233.145 to 32.167.233.15032.167.233.1516
5232.167.233.152/2932.167.233.153 to 32.167.233.15832.167.233.1596
5332.167.233.160/2932.167.233.161 to 32.167.233.16632.167.233.1676
5432.167.233.168/2932.167.233.169 to 32.167.233.17432.167.233.1756
5532.167.233.176/2932.167.233.177 to 32.167.233.18232.167.233.1836
5632.167.233.184/2932.167.233.185 to 32.167.233.19032.167.233.1916
5732.167.233.192/2932.167.233.193 to 32.167.233.19832.167.233.1996
5832.167.233.200/2932.167.233.201 to 32.167.233.20632.167.233.2076
5932.167.233.208/2932.167.233.209 to 32.167.233.21432.167.233.2156
6032.167.233.216/2932.167.233.217 to 32.167.233.22232.167.233.2236
6132.167.233.224/2932.167.233.225 to 32.167.233.23032.167.233.2316
6232.167.233.232/2932.167.233.233 to 32.167.233.23832.167.233.2396
6332.167.233.240/2932.167.233.241 to 32.167.233.24632.167.233.2476
6432.167.233.248/2932.167.233.249 to 32.167.233.25432.167.233.2556
6532.167.234.0/2932.167.234.1 to 32.167.234.632.167.234.76
6632.167.234.8/2932.167.234.9 to 32.167.234.1432.167.234.156
6732.167.234.16/2932.167.234.17 to 32.167.234.2232.167.234.236
6832.167.234.24/2932.167.234.25 to 32.167.234.3032.167.234.316
6932.167.234.32/2932.167.234.33 to 32.167.234.3832.167.234.396
7032.167.234.40/2932.167.234.41 to 32.167.234.4632.167.234.476
7132.167.234.48/2932.167.234.49 to 32.167.234.5432.167.234.556
7232.167.234.56/2932.167.234.57 to 32.167.234.6232.167.234.636
7332.167.234.64/2932.167.234.65 to 32.167.234.7032.167.234.716
7432.167.234.72/2932.167.234.73 to 32.167.234.7832.167.234.796
7532.167.234.80/2932.167.234.81 to 32.167.234.8632.167.234.876
7632.167.234.88/2932.167.234.89 to 32.167.234.9432.167.234.956
7732.167.234.96/2932.167.234.97 to 32.167.234.10232.167.234.1036
7832.167.234.104/2932.167.234.105 to 32.167.234.11032.167.234.1116
7932.167.234.112/2932.167.234.113 to 32.167.234.11832.167.234.1196
8032.167.234.120/2932.167.234.121 to 32.167.234.12632.167.234.1276
8132.167.234.128/2932.167.234.129 to 32.167.234.13432.167.234.1356
8232.167.234.136/2932.167.234.137 to 32.167.234.14232.167.234.1436
8332.167.234.144/2932.167.234.145 to 32.167.234.15032.167.234.1516
8432.167.234.152/2932.167.234.153 to 32.167.234.15832.167.234.1596
8532.167.234.160/2932.167.234.161 to 32.167.234.16632.167.234.1676
8632.167.234.168/2932.167.234.169 to 32.167.234.17432.167.234.1756
8732.167.234.176/2932.167.234.177 to 32.167.234.18232.167.234.1836
8832.167.234.184/2932.167.234.185 to 32.167.234.19032.167.234.1916
8932.167.234.192/2932.167.234.193 to 32.167.234.19832.167.234.1996
9032.167.234.200/2932.167.234.201 to 32.167.234.20632.167.234.2076
9132.167.234.208/2932.167.234.209 to 32.167.234.21432.167.234.2156
9232.167.234.216/2932.167.234.217 to 32.167.234.22232.167.234.2236
9332.167.234.224/2932.167.234.225 to 32.167.234.23032.167.234.2316
9432.167.234.232/2932.167.234.233 to 32.167.234.23832.167.234.2396
9532.167.234.240/2932.167.234.241 to 32.167.234.24632.167.234.2476
9632.167.234.248/2932.167.234.249 to 32.167.234.25432.167.234.2556
9732.167.235.0/2932.167.235.1 to 32.167.235.632.167.235.76
9832.167.235.8/2932.167.235.9 to 32.167.235.1432.167.235.156
9932.167.235.16/2932.167.235.17 to 32.167.235.2232.167.235.236
10032.167.235.24/2932.167.235.25 to 32.167.235.3032.167.235.316
10132.167.235.32/2932.167.235.33 to 32.167.235.3832.167.235.396
10232.167.235.40/2932.167.235.41 to 32.167.235.4632.167.235.476
10332.167.235.48/2932.167.235.49 to 32.167.235.5432.167.235.556
10432.167.235.56/2932.167.235.57 to 32.167.235.6232.167.235.636
10532.167.235.64/2932.167.235.65 to 32.167.235.7032.167.235.716
10632.167.235.72/2932.167.235.73 to 32.167.235.7832.167.235.796
10732.167.235.80/2932.167.235.81 to 32.167.235.8632.167.235.876
10832.167.235.88/2932.167.235.89 to 32.167.235.9432.167.235.956
10932.167.235.96/2932.167.235.97 to 32.167.235.10232.167.235.1036
11032.167.235.104/2932.167.235.105 to 32.167.235.11032.167.235.1116
11132.167.235.112/2932.167.235.113 to 32.167.235.11832.167.235.1196
11232.167.235.120/2932.167.235.121 to 32.167.235.12632.167.235.1276
11332.167.235.128/2932.167.235.129 to 32.167.235.13432.167.235.1356
11432.167.235.136/2932.167.235.137 to 32.167.235.14232.167.235.1436
11532.167.235.144/2932.167.235.145 to 32.167.235.15032.167.235.1516
11632.167.235.152/2932.167.235.153 to 32.167.235.15832.167.235.1596
11732.167.235.160/2932.167.235.161 to 32.167.235.16632.167.235.1676
11832.167.235.168/2932.167.235.169 to 32.167.235.17432.167.235.1756
11932.167.235.176/2932.167.235.177 to 32.167.235.18232.167.235.1836
12032.167.235.184/2932.167.235.185 to 32.167.235.19032.167.235.1916
12132.167.235.192/2932.167.235.193 to 32.167.235.19832.167.235.1996
12232.167.235.200/2932.167.235.201 to 32.167.235.20632.167.235.2076
12332.167.235.208/2932.167.235.209 to 32.167.235.21432.167.235.2156
12432.167.235.216/2932.167.235.217 to 32.167.235.22232.167.235.2236
12532.167.235.224/2932.167.235.225 to 32.167.235.23032.167.235.2316
12632.167.235.232/2932.167.235.233 to 32.167.235.23832.167.235.2396
12732.167.235.240/2932.167.235.241 to 32.167.235.24632.167.235.2476
12832.167.235.248/2932.167.235.249 to 32.167.235.25432.167.235.2556

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.