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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.

Network75.167.96.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
75.167.96.0
Broadcast address
75.167.99.255
First usable
75.167.96.1
Last usable
75.167.99.254
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 4BA76000 · Integer 1269260288 to 1269261311
Reverse DNS zones
96.167.75.in-addr.arpa
97.167.75.in-addr.arpa
98.167.75.in-addr.arpa
99.167.75.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
Address01001011.10100111.01100000.0000000075.167.96.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network01001011.10100111.01100000.0000000075.167.96.0
Broadcast01001011.10100111.01100011.1111111175.167.99.255
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)

75.167.96.0/22 makes 128 subnets of /29.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
175.167.96.0/2975.167.96.1 to 75.167.96.675.167.96.76
275.167.96.8/2975.167.96.9 to 75.167.96.1475.167.96.156
375.167.96.16/2975.167.96.17 to 75.167.96.2275.167.96.236
475.167.96.24/2975.167.96.25 to 75.167.96.3075.167.96.316
575.167.96.32/2975.167.96.33 to 75.167.96.3875.167.96.396
675.167.96.40/2975.167.96.41 to 75.167.96.4675.167.96.476
775.167.96.48/2975.167.96.49 to 75.167.96.5475.167.96.556
875.167.96.56/2975.167.96.57 to 75.167.96.6275.167.96.636
975.167.96.64/2975.167.96.65 to 75.167.96.7075.167.96.716
1075.167.96.72/2975.167.96.73 to 75.167.96.7875.167.96.796
1175.167.96.80/2975.167.96.81 to 75.167.96.8675.167.96.876
1275.167.96.88/2975.167.96.89 to 75.167.96.9475.167.96.956
1375.167.96.96/2975.167.96.97 to 75.167.96.10275.167.96.1036
1475.167.96.104/2975.167.96.105 to 75.167.96.11075.167.96.1116
1575.167.96.112/2975.167.96.113 to 75.167.96.11875.167.96.1196
1675.167.96.120/2975.167.96.121 to 75.167.96.12675.167.96.1276
1775.167.96.128/2975.167.96.129 to 75.167.96.13475.167.96.1356
1875.167.96.136/2975.167.96.137 to 75.167.96.14275.167.96.1436
1975.167.96.144/2975.167.96.145 to 75.167.96.15075.167.96.1516
2075.167.96.152/2975.167.96.153 to 75.167.96.15875.167.96.1596
2175.167.96.160/2975.167.96.161 to 75.167.96.16675.167.96.1676
2275.167.96.168/2975.167.96.169 to 75.167.96.17475.167.96.1756
2375.167.96.176/2975.167.96.177 to 75.167.96.18275.167.96.1836
2475.167.96.184/2975.167.96.185 to 75.167.96.19075.167.96.1916
2575.167.96.192/2975.167.96.193 to 75.167.96.19875.167.96.1996
2675.167.96.200/2975.167.96.201 to 75.167.96.20675.167.96.2076
2775.167.96.208/2975.167.96.209 to 75.167.96.21475.167.96.2156
2875.167.96.216/2975.167.96.217 to 75.167.96.22275.167.96.2236
2975.167.96.224/2975.167.96.225 to 75.167.96.23075.167.96.2316
3075.167.96.232/2975.167.96.233 to 75.167.96.23875.167.96.2396
3175.167.96.240/2975.167.96.241 to 75.167.96.24675.167.96.2476
3275.167.96.248/2975.167.96.249 to 75.167.96.25475.167.96.2556
3375.167.97.0/2975.167.97.1 to 75.167.97.675.167.97.76
3475.167.97.8/2975.167.97.9 to 75.167.97.1475.167.97.156
3575.167.97.16/2975.167.97.17 to 75.167.97.2275.167.97.236
3675.167.97.24/2975.167.97.25 to 75.167.97.3075.167.97.316
3775.167.97.32/2975.167.97.33 to 75.167.97.3875.167.97.396
3875.167.97.40/2975.167.97.41 to 75.167.97.4675.167.97.476
3975.167.97.48/2975.167.97.49 to 75.167.97.5475.167.97.556
4075.167.97.56/2975.167.97.57 to 75.167.97.6275.167.97.636
4175.167.97.64/2975.167.97.65 to 75.167.97.7075.167.97.716
4275.167.97.72/2975.167.97.73 to 75.167.97.7875.167.97.796
4375.167.97.80/2975.167.97.81 to 75.167.97.8675.167.97.876
4475.167.97.88/2975.167.97.89 to 75.167.97.9475.167.97.956
4575.167.97.96/2975.167.97.97 to 75.167.97.10275.167.97.1036
4675.167.97.104/2975.167.97.105 to 75.167.97.11075.167.97.1116
4775.167.97.112/2975.167.97.113 to 75.167.97.11875.167.97.1196
4875.167.97.120/2975.167.97.121 to 75.167.97.12675.167.97.1276
4975.167.97.128/2975.167.97.129 to 75.167.97.13475.167.97.1356
5075.167.97.136/2975.167.97.137 to 75.167.97.14275.167.97.1436
5175.167.97.144/2975.167.97.145 to 75.167.97.15075.167.97.1516
5275.167.97.152/2975.167.97.153 to 75.167.97.15875.167.97.1596
5375.167.97.160/2975.167.97.161 to 75.167.97.16675.167.97.1676
5475.167.97.168/2975.167.97.169 to 75.167.97.17475.167.97.1756
5575.167.97.176/2975.167.97.177 to 75.167.97.18275.167.97.1836
5675.167.97.184/2975.167.97.185 to 75.167.97.19075.167.97.1916
5775.167.97.192/2975.167.97.193 to 75.167.97.19875.167.97.1996
5875.167.97.200/2975.167.97.201 to 75.167.97.20675.167.97.2076
5975.167.97.208/2975.167.97.209 to 75.167.97.21475.167.97.2156
6075.167.97.216/2975.167.97.217 to 75.167.97.22275.167.97.2236
6175.167.97.224/2975.167.97.225 to 75.167.97.23075.167.97.2316
6275.167.97.232/2975.167.97.233 to 75.167.97.23875.167.97.2396
6375.167.97.240/2975.167.97.241 to 75.167.97.24675.167.97.2476
6475.167.97.248/2975.167.97.249 to 75.167.97.25475.167.97.2556
6575.167.98.0/2975.167.98.1 to 75.167.98.675.167.98.76
6675.167.98.8/2975.167.98.9 to 75.167.98.1475.167.98.156
6775.167.98.16/2975.167.98.17 to 75.167.98.2275.167.98.236
6875.167.98.24/2975.167.98.25 to 75.167.98.3075.167.98.316
6975.167.98.32/2975.167.98.33 to 75.167.98.3875.167.98.396
7075.167.98.40/2975.167.98.41 to 75.167.98.4675.167.98.476
7175.167.98.48/2975.167.98.49 to 75.167.98.5475.167.98.556
7275.167.98.56/2975.167.98.57 to 75.167.98.6275.167.98.636
7375.167.98.64/2975.167.98.65 to 75.167.98.7075.167.98.716
7475.167.98.72/2975.167.98.73 to 75.167.98.7875.167.98.796
7575.167.98.80/2975.167.98.81 to 75.167.98.8675.167.98.876
7675.167.98.88/2975.167.98.89 to 75.167.98.9475.167.98.956
7775.167.98.96/2975.167.98.97 to 75.167.98.10275.167.98.1036
7875.167.98.104/2975.167.98.105 to 75.167.98.11075.167.98.1116
7975.167.98.112/2975.167.98.113 to 75.167.98.11875.167.98.1196
8075.167.98.120/2975.167.98.121 to 75.167.98.12675.167.98.1276
8175.167.98.128/2975.167.98.129 to 75.167.98.13475.167.98.1356
8275.167.98.136/2975.167.98.137 to 75.167.98.14275.167.98.1436
8375.167.98.144/2975.167.98.145 to 75.167.98.15075.167.98.1516
8475.167.98.152/2975.167.98.153 to 75.167.98.15875.167.98.1596
8575.167.98.160/2975.167.98.161 to 75.167.98.16675.167.98.1676
8675.167.98.168/2975.167.98.169 to 75.167.98.17475.167.98.1756
8775.167.98.176/2975.167.98.177 to 75.167.98.18275.167.98.1836
8875.167.98.184/2975.167.98.185 to 75.167.98.19075.167.98.1916
8975.167.98.192/2975.167.98.193 to 75.167.98.19875.167.98.1996
9075.167.98.200/2975.167.98.201 to 75.167.98.20675.167.98.2076
9175.167.98.208/2975.167.98.209 to 75.167.98.21475.167.98.2156
9275.167.98.216/2975.167.98.217 to 75.167.98.22275.167.98.2236
9375.167.98.224/2975.167.98.225 to 75.167.98.23075.167.98.2316
9475.167.98.232/2975.167.98.233 to 75.167.98.23875.167.98.2396
9575.167.98.240/2975.167.98.241 to 75.167.98.24675.167.98.2476
9675.167.98.248/2975.167.98.249 to 75.167.98.25475.167.98.2556
9775.167.99.0/2975.167.99.1 to 75.167.99.675.167.99.76
9875.167.99.8/2975.167.99.9 to 75.167.99.1475.167.99.156
9975.167.99.16/2975.167.99.17 to 75.167.99.2275.167.99.236
10075.167.99.24/2975.167.99.25 to 75.167.99.3075.167.99.316
10175.167.99.32/2975.167.99.33 to 75.167.99.3875.167.99.396
10275.167.99.40/2975.167.99.41 to 75.167.99.4675.167.99.476
10375.167.99.48/2975.167.99.49 to 75.167.99.5475.167.99.556
10475.167.99.56/2975.167.99.57 to 75.167.99.6275.167.99.636
10575.167.99.64/2975.167.99.65 to 75.167.99.7075.167.99.716
10675.167.99.72/2975.167.99.73 to 75.167.99.7875.167.99.796
10775.167.99.80/2975.167.99.81 to 75.167.99.8675.167.99.876
10875.167.99.88/2975.167.99.89 to 75.167.99.9475.167.99.956
10975.167.99.96/2975.167.99.97 to 75.167.99.10275.167.99.1036
11075.167.99.104/2975.167.99.105 to 75.167.99.11075.167.99.1116
11175.167.99.112/2975.167.99.113 to 75.167.99.11875.167.99.1196
11275.167.99.120/2975.167.99.121 to 75.167.99.12675.167.99.1276
11375.167.99.128/2975.167.99.129 to 75.167.99.13475.167.99.1356
11475.167.99.136/2975.167.99.137 to 75.167.99.14275.167.99.1436
11575.167.99.144/2975.167.99.145 to 75.167.99.15075.167.99.1516
11675.167.99.152/2975.167.99.153 to 75.167.99.15875.167.99.1596
11775.167.99.160/2975.167.99.161 to 75.167.99.16675.167.99.1676
11875.167.99.168/2975.167.99.169 to 75.167.99.17475.167.99.1756
11975.167.99.176/2975.167.99.177 to 75.167.99.18275.167.99.1836
12075.167.99.184/2975.167.99.185 to 75.167.99.19075.167.99.1916
12175.167.99.192/2975.167.99.193 to 75.167.99.19875.167.99.1996
12275.167.99.200/2975.167.99.201 to 75.167.99.20675.167.99.2076
12375.167.99.208/2975.167.99.209 to 75.167.99.21475.167.99.2156
12475.167.99.216/2975.167.99.217 to 75.167.99.22275.167.99.2236
12575.167.99.224/2975.167.99.225 to 75.167.99.23075.167.99.2316
12675.167.99.232/2975.167.99.233 to 75.167.99.23875.167.99.2396
12775.167.99.240/2975.167.99.241 to 75.167.99.24675.167.99.2476
12875.167.99.248/2975.167.99.249 to 75.167.99.25475.167.99.2556

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.