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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.

Network47.167.84.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
47.167.84.0
Broadcast address
47.167.87.255
First usable
47.167.84.1
Last usable
47.167.87.254
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 2FA75400 · Integer 799495168 to 799496191
Reverse DNS zones
84.167.47.in-addr.arpa
85.167.47.in-addr.arpa
86.167.47.in-addr.arpa
87.167.47.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
Address00101111.10100111.01010100.0000000047.167.84.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network00101111.10100111.01010100.0000000047.167.84.0
Broadcast00101111.10100111.01010111.1111111147.167.87.255
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)

47.167.84.0/22 makes 128 subnets of /29.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
147.167.84.0/2947.167.84.1 to 47.167.84.647.167.84.76
247.167.84.8/2947.167.84.9 to 47.167.84.1447.167.84.156
347.167.84.16/2947.167.84.17 to 47.167.84.2247.167.84.236
447.167.84.24/2947.167.84.25 to 47.167.84.3047.167.84.316
547.167.84.32/2947.167.84.33 to 47.167.84.3847.167.84.396
647.167.84.40/2947.167.84.41 to 47.167.84.4647.167.84.476
747.167.84.48/2947.167.84.49 to 47.167.84.5447.167.84.556
847.167.84.56/2947.167.84.57 to 47.167.84.6247.167.84.636
947.167.84.64/2947.167.84.65 to 47.167.84.7047.167.84.716
1047.167.84.72/2947.167.84.73 to 47.167.84.7847.167.84.796
1147.167.84.80/2947.167.84.81 to 47.167.84.8647.167.84.876
1247.167.84.88/2947.167.84.89 to 47.167.84.9447.167.84.956
1347.167.84.96/2947.167.84.97 to 47.167.84.10247.167.84.1036
1447.167.84.104/2947.167.84.105 to 47.167.84.11047.167.84.1116
1547.167.84.112/2947.167.84.113 to 47.167.84.11847.167.84.1196
1647.167.84.120/2947.167.84.121 to 47.167.84.12647.167.84.1276
1747.167.84.128/2947.167.84.129 to 47.167.84.13447.167.84.1356
1847.167.84.136/2947.167.84.137 to 47.167.84.14247.167.84.1436
1947.167.84.144/2947.167.84.145 to 47.167.84.15047.167.84.1516
2047.167.84.152/2947.167.84.153 to 47.167.84.15847.167.84.1596
2147.167.84.160/2947.167.84.161 to 47.167.84.16647.167.84.1676
2247.167.84.168/2947.167.84.169 to 47.167.84.17447.167.84.1756
2347.167.84.176/2947.167.84.177 to 47.167.84.18247.167.84.1836
2447.167.84.184/2947.167.84.185 to 47.167.84.19047.167.84.1916
2547.167.84.192/2947.167.84.193 to 47.167.84.19847.167.84.1996
2647.167.84.200/2947.167.84.201 to 47.167.84.20647.167.84.2076
2747.167.84.208/2947.167.84.209 to 47.167.84.21447.167.84.2156
2847.167.84.216/2947.167.84.217 to 47.167.84.22247.167.84.2236
2947.167.84.224/2947.167.84.225 to 47.167.84.23047.167.84.2316
3047.167.84.232/2947.167.84.233 to 47.167.84.23847.167.84.2396
3147.167.84.240/2947.167.84.241 to 47.167.84.24647.167.84.2476
3247.167.84.248/2947.167.84.249 to 47.167.84.25447.167.84.2556
3347.167.85.0/2947.167.85.1 to 47.167.85.647.167.85.76
3447.167.85.8/2947.167.85.9 to 47.167.85.1447.167.85.156
3547.167.85.16/2947.167.85.17 to 47.167.85.2247.167.85.236
3647.167.85.24/2947.167.85.25 to 47.167.85.3047.167.85.316
3747.167.85.32/2947.167.85.33 to 47.167.85.3847.167.85.396
3847.167.85.40/2947.167.85.41 to 47.167.85.4647.167.85.476
3947.167.85.48/2947.167.85.49 to 47.167.85.5447.167.85.556
4047.167.85.56/2947.167.85.57 to 47.167.85.6247.167.85.636
4147.167.85.64/2947.167.85.65 to 47.167.85.7047.167.85.716
4247.167.85.72/2947.167.85.73 to 47.167.85.7847.167.85.796
4347.167.85.80/2947.167.85.81 to 47.167.85.8647.167.85.876
4447.167.85.88/2947.167.85.89 to 47.167.85.9447.167.85.956
4547.167.85.96/2947.167.85.97 to 47.167.85.10247.167.85.1036
4647.167.85.104/2947.167.85.105 to 47.167.85.11047.167.85.1116
4747.167.85.112/2947.167.85.113 to 47.167.85.11847.167.85.1196
4847.167.85.120/2947.167.85.121 to 47.167.85.12647.167.85.1276
4947.167.85.128/2947.167.85.129 to 47.167.85.13447.167.85.1356
5047.167.85.136/2947.167.85.137 to 47.167.85.14247.167.85.1436
5147.167.85.144/2947.167.85.145 to 47.167.85.15047.167.85.1516
5247.167.85.152/2947.167.85.153 to 47.167.85.15847.167.85.1596
5347.167.85.160/2947.167.85.161 to 47.167.85.16647.167.85.1676
5447.167.85.168/2947.167.85.169 to 47.167.85.17447.167.85.1756
5547.167.85.176/2947.167.85.177 to 47.167.85.18247.167.85.1836
5647.167.85.184/2947.167.85.185 to 47.167.85.19047.167.85.1916
5747.167.85.192/2947.167.85.193 to 47.167.85.19847.167.85.1996
5847.167.85.200/2947.167.85.201 to 47.167.85.20647.167.85.2076
5947.167.85.208/2947.167.85.209 to 47.167.85.21447.167.85.2156
6047.167.85.216/2947.167.85.217 to 47.167.85.22247.167.85.2236
6147.167.85.224/2947.167.85.225 to 47.167.85.23047.167.85.2316
6247.167.85.232/2947.167.85.233 to 47.167.85.23847.167.85.2396
6347.167.85.240/2947.167.85.241 to 47.167.85.24647.167.85.2476
6447.167.85.248/2947.167.85.249 to 47.167.85.25447.167.85.2556
6547.167.86.0/2947.167.86.1 to 47.167.86.647.167.86.76
6647.167.86.8/2947.167.86.9 to 47.167.86.1447.167.86.156
6747.167.86.16/2947.167.86.17 to 47.167.86.2247.167.86.236
6847.167.86.24/2947.167.86.25 to 47.167.86.3047.167.86.316
6947.167.86.32/2947.167.86.33 to 47.167.86.3847.167.86.396
7047.167.86.40/2947.167.86.41 to 47.167.86.4647.167.86.476
7147.167.86.48/2947.167.86.49 to 47.167.86.5447.167.86.556
7247.167.86.56/2947.167.86.57 to 47.167.86.6247.167.86.636
7347.167.86.64/2947.167.86.65 to 47.167.86.7047.167.86.716
7447.167.86.72/2947.167.86.73 to 47.167.86.7847.167.86.796
7547.167.86.80/2947.167.86.81 to 47.167.86.8647.167.86.876
7647.167.86.88/2947.167.86.89 to 47.167.86.9447.167.86.956
7747.167.86.96/2947.167.86.97 to 47.167.86.10247.167.86.1036
7847.167.86.104/2947.167.86.105 to 47.167.86.11047.167.86.1116
7947.167.86.112/2947.167.86.113 to 47.167.86.11847.167.86.1196
8047.167.86.120/2947.167.86.121 to 47.167.86.12647.167.86.1276
8147.167.86.128/2947.167.86.129 to 47.167.86.13447.167.86.1356
8247.167.86.136/2947.167.86.137 to 47.167.86.14247.167.86.1436
8347.167.86.144/2947.167.86.145 to 47.167.86.15047.167.86.1516
8447.167.86.152/2947.167.86.153 to 47.167.86.15847.167.86.1596
8547.167.86.160/2947.167.86.161 to 47.167.86.16647.167.86.1676
8647.167.86.168/2947.167.86.169 to 47.167.86.17447.167.86.1756
8747.167.86.176/2947.167.86.177 to 47.167.86.18247.167.86.1836
8847.167.86.184/2947.167.86.185 to 47.167.86.19047.167.86.1916
8947.167.86.192/2947.167.86.193 to 47.167.86.19847.167.86.1996
9047.167.86.200/2947.167.86.201 to 47.167.86.20647.167.86.2076
9147.167.86.208/2947.167.86.209 to 47.167.86.21447.167.86.2156
9247.167.86.216/2947.167.86.217 to 47.167.86.22247.167.86.2236
9347.167.86.224/2947.167.86.225 to 47.167.86.23047.167.86.2316
9447.167.86.232/2947.167.86.233 to 47.167.86.23847.167.86.2396
9547.167.86.240/2947.167.86.241 to 47.167.86.24647.167.86.2476
9647.167.86.248/2947.167.86.249 to 47.167.86.25447.167.86.2556
9747.167.87.0/2947.167.87.1 to 47.167.87.647.167.87.76
9847.167.87.8/2947.167.87.9 to 47.167.87.1447.167.87.156
9947.167.87.16/2947.167.87.17 to 47.167.87.2247.167.87.236
10047.167.87.24/2947.167.87.25 to 47.167.87.3047.167.87.316
10147.167.87.32/2947.167.87.33 to 47.167.87.3847.167.87.396
10247.167.87.40/2947.167.87.41 to 47.167.87.4647.167.87.476
10347.167.87.48/2947.167.87.49 to 47.167.87.5447.167.87.556
10447.167.87.56/2947.167.87.57 to 47.167.87.6247.167.87.636
10547.167.87.64/2947.167.87.65 to 47.167.87.7047.167.87.716
10647.167.87.72/2947.167.87.73 to 47.167.87.7847.167.87.796
10747.167.87.80/2947.167.87.81 to 47.167.87.8647.167.87.876
10847.167.87.88/2947.167.87.89 to 47.167.87.9447.167.87.956
10947.167.87.96/2947.167.87.97 to 47.167.87.10247.167.87.1036
11047.167.87.104/2947.167.87.105 to 47.167.87.11047.167.87.1116
11147.167.87.112/2947.167.87.113 to 47.167.87.11847.167.87.1196
11247.167.87.120/2947.167.87.121 to 47.167.87.12647.167.87.1276
11347.167.87.128/2947.167.87.129 to 47.167.87.13447.167.87.1356
11447.167.87.136/2947.167.87.137 to 47.167.87.14247.167.87.1436
11547.167.87.144/2947.167.87.145 to 47.167.87.15047.167.87.1516
11647.167.87.152/2947.167.87.153 to 47.167.87.15847.167.87.1596
11747.167.87.160/2947.167.87.161 to 47.167.87.16647.167.87.1676
11847.167.87.168/2947.167.87.169 to 47.167.87.17447.167.87.1756
11947.167.87.176/2947.167.87.177 to 47.167.87.18247.167.87.1836
12047.167.87.184/2947.167.87.185 to 47.167.87.19047.167.87.1916
12147.167.87.192/2947.167.87.193 to 47.167.87.19847.167.87.1996
12247.167.87.200/2947.167.87.201 to 47.167.87.20647.167.87.2076
12347.167.87.208/2947.167.87.209 to 47.167.87.21447.167.87.2156
12447.167.87.216/2947.167.87.217 to 47.167.87.22247.167.87.2236
12547.167.87.224/2947.167.87.225 to 47.167.87.23047.167.87.2316
12647.167.87.232/2947.167.87.233 to 47.167.87.23847.167.87.2396
12747.167.87.240/2947.167.87.241 to 47.167.87.24647.167.87.2476
12847.167.87.248/2947.167.87.249 to 47.167.87.25447.167.87.2556

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.