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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.

Network50.167.232.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
50.167.232.0
Broadcast address
50.167.235.255
First usable
50.167.232.1
Last usable
50.167.235.254
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 32A7E800 · Integer 849864704 to 849865727
Reverse DNS zones
232.167.50.in-addr.arpa
233.167.50.in-addr.arpa
234.167.50.in-addr.arpa
235.167.50.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
Address00110010.10100111.11101000.0000000050.167.232.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network00110010.10100111.11101000.0000000050.167.232.0
Broadcast00110010.10100111.11101011.1111111150.167.235.255
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)

50.167.232.0/22 makes 128 subnets of /29.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
150.167.232.0/2950.167.232.1 to 50.167.232.650.167.232.76
250.167.232.8/2950.167.232.9 to 50.167.232.1450.167.232.156
350.167.232.16/2950.167.232.17 to 50.167.232.2250.167.232.236
450.167.232.24/2950.167.232.25 to 50.167.232.3050.167.232.316
550.167.232.32/2950.167.232.33 to 50.167.232.3850.167.232.396
650.167.232.40/2950.167.232.41 to 50.167.232.4650.167.232.476
750.167.232.48/2950.167.232.49 to 50.167.232.5450.167.232.556
850.167.232.56/2950.167.232.57 to 50.167.232.6250.167.232.636
950.167.232.64/2950.167.232.65 to 50.167.232.7050.167.232.716
1050.167.232.72/2950.167.232.73 to 50.167.232.7850.167.232.796
1150.167.232.80/2950.167.232.81 to 50.167.232.8650.167.232.876
1250.167.232.88/2950.167.232.89 to 50.167.232.9450.167.232.956
1350.167.232.96/2950.167.232.97 to 50.167.232.10250.167.232.1036
1450.167.232.104/2950.167.232.105 to 50.167.232.11050.167.232.1116
1550.167.232.112/2950.167.232.113 to 50.167.232.11850.167.232.1196
1650.167.232.120/2950.167.232.121 to 50.167.232.12650.167.232.1276
1750.167.232.128/2950.167.232.129 to 50.167.232.13450.167.232.1356
1850.167.232.136/2950.167.232.137 to 50.167.232.14250.167.232.1436
1950.167.232.144/2950.167.232.145 to 50.167.232.15050.167.232.1516
2050.167.232.152/2950.167.232.153 to 50.167.232.15850.167.232.1596
2150.167.232.160/2950.167.232.161 to 50.167.232.16650.167.232.1676
2250.167.232.168/2950.167.232.169 to 50.167.232.17450.167.232.1756
2350.167.232.176/2950.167.232.177 to 50.167.232.18250.167.232.1836
2450.167.232.184/2950.167.232.185 to 50.167.232.19050.167.232.1916
2550.167.232.192/2950.167.232.193 to 50.167.232.19850.167.232.1996
2650.167.232.200/2950.167.232.201 to 50.167.232.20650.167.232.2076
2750.167.232.208/2950.167.232.209 to 50.167.232.21450.167.232.2156
2850.167.232.216/2950.167.232.217 to 50.167.232.22250.167.232.2236
2950.167.232.224/2950.167.232.225 to 50.167.232.23050.167.232.2316
3050.167.232.232/2950.167.232.233 to 50.167.232.23850.167.232.2396
3150.167.232.240/2950.167.232.241 to 50.167.232.24650.167.232.2476
3250.167.232.248/2950.167.232.249 to 50.167.232.25450.167.232.2556
3350.167.233.0/2950.167.233.1 to 50.167.233.650.167.233.76
3450.167.233.8/2950.167.233.9 to 50.167.233.1450.167.233.156
3550.167.233.16/2950.167.233.17 to 50.167.233.2250.167.233.236
3650.167.233.24/2950.167.233.25 to 50.167.233.3050.167.233.316
3750.167.233.32/2950.167.233.33 to 50.167.233.3850.167.233.396
3850.167.233.40/2950.167.233.41 to 50.167.233.4650.167.233.476
3950.167.233.48/2950.167.233.49 to 50.167.233.5450.167.233.556
4050.167.233.56/2950.167.233.57 to 50.167.233.6250.167.233.636
4150.167.233.64/2950.167.233.65 to 50.167.233.7050.167.233.716
4250.167.233.72/2950.167.233.73 to 50.167.233.7850.167.233.796
4350.167.233.80/2950.167.233.81 to 50.167.233.8650.167.233.876
4450.167.233.88/2950.167.233.89 to 50.167.233.9450.167.233.956
4550.167.233.96/2950.167.233.97 to 50.167.233.10250.167.233.1036
4650.167.233.104/2950.167.233.105 to 50.167.233.11050.167.233.1116
4750.167.233.112/2950.167.233.113 to 50.167.233.11850.167.233.1196
4850.167.233.120/2950.167.233.121 to 50.167.233.12650.167.233.1276
4950.167.233.128/2950.167.233.129 to 50.167.233.13450.167.233.1356
5050.167.233.136/2950.167.233.137 to 50.167.233.14250.167.233.1436
5150.167.233.144/2950.167.233.145 to 50.167.233.15050.167.233.1516
5250.167.233.152/2950.167.233.153 to 50.167.233.15850.167.233.1596
5350.167.233.160/2950.167.233.161 to 50.167.233.16650.167.233.1676
5450.167.233.168/2950.167.233.169 to 50.167.233.17450.167.233.1756
5550.167.233.176/2950.167.233.177 to 50.167.233.18250.167.233.1836
5650.167.233.184/2950.167.233.185 to 50.167.233.19050.167.233.1916
5750.167.233.192/2950.167.233.193 to 50.167.233.19850.167.233.1996
5850.167.233.200/2950.167.233.201 to 50.167.233.20650.167.233.2076
5950.167.233.208/2950.167.233.209 to 50.167.233.21450.167.233.2156
6050.167.233.216/2950.167.233.217 to 50.167.233.22250.167.233.2236
6150.167.233.224/2950.167.233.225 to 50.167.233.23050.167.233.2316
6250.167.233.232/2950.167.233.233 to 50.167.233.23850.167.233.2396
6350.167.233.240/2950.167.233.241 to 50.167.233.24650.167.233.2476
6450.167.233.248/2950.167.233.249 to 50.167.233.25450.167.233.2556
6550.167.234.0/2950.167.234.1 to 50.167.234.650.167.234.76
6650.167.234.8/2950.167.234.9 to 50.167.234.1450.167.234.156
6750.167.234.16/2950.167.234.17 to 50.167.234.2250.167.234.236
6850.167.234.24/2950.167.234.25 to 50.167.234.3050.167.234.316
6950.167.234.32/2950.167.234.33 to 50.167.234.3850.167.234.396
7050.167.234.40/2950.167.234.41 to 50.167.234.4650.167.234.476
7150.167.234.48/2950.167.234.49 to 50.167.234.5450.167.234.556
7250.167.234.56/2950.167.234.57 to 50.167.234.6250.167.234.636
7350.167.234.64/2950.167.234.65 to 50.167.234.7050.167.234.716
7450.167.234.72/2950.167.234.73 to 50.167.234.7850.167.234.796
7550.167.234.80/2950.167.234.81 to 50.167.234.8650.167.234.876
7650.167.234.88/2950.167.234.89 to 50.167.234.9450.167.234.956
7750.167.234.96/2950.167.234.97 to 50.167.234.10250.167.234.1036
7850.167.234.104/2950.167.234.105 to 50.167.234.11050.167.234.1116
7950.167.234.112/2950.167.234.113 to 50.167.234.11850.167.234.1196
8050.167.234.120/2950.167.234.121 to 50.167.234.12650.167.234.1276
8150.167.234.128/2950.167.234.129 to 50.167.234.13450.167.234.1356
8250.167.234.136/2950.167.234.137 to 50.167.234.14250.167.234.1436
8350.167.234.144/2950.167.234.145 to 50.167.234.15050.167.234.1516
8450.167.234.152/2950.167.234.153 to 50.167.234.15850.167.234.1596
8550.167.234.160/2950.167.234.161 to 50.167.234.16650.167.234.1676
8650.167.234.168/2950.167.234.169 to 50.167.234.17450.167.234.1756
8750.167.234.176/2950.167.234.177 to 50.167.234.18250.167.234.1836
8850.167.234.184/2950.167.234.185 to 50.167.234.19050.167.234.1916
8950.167.234.192/2950.167.234.193 to 50.167.234.19850.167.234.1996
9050.167.234.200/2950.167.234.201 to 50.167.234.20650.167.234.2076
9150.167.234.208/2950.167.234.209 to 50.167.234.21450.167.234.2156
9250.167.234.216/2950.167.234.217 to 50.167.234.22250.167.234.2236
9350.167.234.224/2950.167.234.225 to 50.167.234.23050.167.234.2316
9450.167.234.232/2950.167.234.233 to 50.167.234.23850.167.234.2396
9550.167.234.240/2950.167.234.241 to 50.167.234.24650.167.234.2476
9650.167.234.248/2950.167.234.249 to 50.167.234.25450.167.234.2556
9750.167.235.0/2950.167.235.1 to 50.167.235.650.167.235.76
9850.167.235.8/2950.167.235.9 to 50.167.235.1450.167.235.156
9950.167.235.16/2950.167.235.17 to 50.167.235.2250.167.235.236
10050.167.235.24/2950.167.235.25 to 50.167.235.3050.167.235.316
10150.167.235.32/2950.167.235.33 to 50.167.235.3850.167.235.396
10250.167.235.40/2950.167.235.41 to 50.167.235.4650.167.235.476
10350.167.235.48/2950.167.235.49 to 50.167.235.5450.167.235.556
10450.167.235.56/2950.167.235.57 to 50.167.235.6250.167.235.636
10550.167.235.64/2950.167.235.65 to 50.167.235.7050.167.235.716
10650.167.235.72/2950.167.235.73 to 50.167.235.7850.167.235.796
10750.167.235.80/2950.167.235.81 to 50.167.235.8650.167.235.876
10850.167.235.88/2950.167.235.89 to 50.167.235.9450.167.235.956
10950.167.235.96/2950.167.235.97 to 50.167.235.10250.167.235.1036
11050.167.235.104/2950.167.235.105 to 50.167.235.11050.167.235.1116
11150.167.235.112/2950.167.235.113 to 50.167.235.11850.167.235.1196
11250.167.235.120/2950.167.235.121 to 50.167.235.12650.167.235.1276
11350.167.235.128/2950.167.235.129 to 50.167.235.13450.167.235.1356
11450.167.235.136/2950.167.235.137 to 50.167.235.14250.167.235.1436
11550.167.235.144/2950.167.235.145 to 50.167.235.15050.167.235.1516
11650.167.235.152/2950.167.235.153 to 50.167.235.15850.167.235.1596
11750.167.235.160/2950.167.235.161 to 50.167.235.16650.167.235.1676
11850.167.235.168/2950.167.235.169 to 50.167.235.17450.167.235.1756
11950.167.235.176/2950.167.235.177 to 50.167.235.18250.167.235.1836
12050.167.235.184/2950.167.235.185 to 50.167.235.19050.167.235.1916
12150.167.235.192/2950.167.235.193 to 50.167.235.19850.167.235.1996
12250.167.235.200/2950.167.235.201 to 50.167.235.20650.167.235.2076
12350.167.235.208/2950.167.235.209 to 50.167.235.21450.167.235.2156
12450.167.235.216/2950.167.235.217 to 50.167.235.22250.167.235.2236
12550.167.235.224/2950.167.235.225 to 50.167.235.23050.167.235.2316
12650.167.235.232/2950.167.235.233 to 50.167.235.23850.167.235.2396
12750.167.235.240/2950.167.235.241 to 50.167.235.24650.167.235.2476
12850.167.235.248/2950.167.235.249 to 50.167.235.25450.167.235.2556

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.