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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.

Network52.78.76.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
52.78.76.0
Broadcast address
52.78.79.255
First usable
52.78.76.1
Last usable
52.78.79.254
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 344E4C00 · Integer 877546496 to 877547519
Reverse DNS zones
76.78.52.in-addr.arpa
77.78.52.in-addr.arpa
78.78.52.in-addr.arpa
79.78.52.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
Address00110100.01001110.01001100.0000000052.78.76.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network00110100.01001110.01001100.0000000052.78.76.0
Broadcast00110100.01001110.01001111.1111111152.78.79.255
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)

52.78.76.0/22 makes 128 subnets of /29.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
152.78.76.0/2952.78.76.1 to 52.78.76.652.78.76.76
252.78.76.8/2952.78.76.9 to 52.78.76.1452.78.76.156
352.78.76.16/2952.78.76.17 to 52.78.76.2252.78.76.236
452.78.76.24/2952.78.76.25 to 52.78.76.3052.78.76.316
552.78.76.32/2952.78.76.33 to 52.78.76.3852.78.76.396
652.78.76.40/2952.78.76.41 to 52.78.76.4652.78.76.476
752.78.76.48/2952.78.76.49 to 52.78.76.5452.78.76.556
852.78.76.56/2952.78.76.57 to 52.78.76.6252.78.76.636
952.78.76.64/2952.78.76.65 to 52.78.76.7052.78.76.716
1052.78.76.72/2952.78.76.73 to 52.78.76.7852.78.76.796
1152.78.76.80/2952.78.76.81 to 52.78.76.8652.78.76.876
1252.78.76.88/2952.78.76.89 to 52.78.76.9452.78.76.956
1352.78.76.96/2952.78.76.97 to 52.78.76.10252.78.76.1036
1452.78.76.104/2952.78.76.105 to 52.78.76.11052.78.76.1116
1552.78.76.112/2952.78.76.113 to 52.78.76.11852.78.76.1196
1652.78.76.120/2952.78.76.121 to 52.78.76.12652.78.76.1276
1752.78.76.128/2952.78.76.129 to 52.78.76.13452.78.76.1356
1852.78.76.136/2952.78.76.137 to 52.78.76.14252.78.76.1436
1952.78.76.144/2952.78.76.145 to 52.78.76.15052.78.76.1516
2052.78.76.152/2952.78.76.153 to 52.78.76.15852.78.76.1596
2152.78.76.160/2952.78.76.161 to 52.78.76.16652.78.76.1676
2252.78.76.168/2952.78.76.169 to 52.78.76.17452.78.76.1756
2352.78.76.176/2952.78.76.177 to 52.78.76.18252.78.76.1836
2452.78.76.184/2952.78.76.185 to 52.78.76.19052.78.76.1916
2552.78.76.192/2952.78.76.193 to 52.78.76.19852.78.76.1996
2652.78.76.200/2952.78.76.201 to 52.78.76.20652.78.76.2076
2752.78.76.208/2952.78.76.209 to 52.78.76.21452.78.76.2156
2852.78.76.216/2952.78.76.217 to 52.78.76.22252.78.76.2236
2952.78.76.224/2952.78.76.225 to 52.78.76.23052.78.76.2316
3052.78.76.232/2952.78.76.233 to 52.78.76.23852.78.76.2396
3152.78.76.240/2952.78.76.241 to 52.78.76.24652.78.76.2476
3252.78.76.248/2952.78.76.249 to 52.78.76.25452.78.76.2556
3352.78.77.0/2952.78.77.1 to 52.78.77.652.78.77.76
3452.78.77.8/2952.78.77.9 to 52.78.77.1452.78.77.156
3552.78.77.16/2952.78.77.17 to 52.78.77.2252.78.77.236
3652.78.77.24/2952.78.77.25 to 52.78.77.3052.78.77.316
3752.78.77.32/2952.78.77.33 to 52.78.77.3852.78.77.396
3852.78.77.40/2952.78.77.41 to 52.78.77.4652.78.77.476
3952.78.77.48/2952.78.77.49 to 52.78.77.5452.78.77.556
4052.78.77.56/2952.78.77.57 to 52.78.77.6252.78.77.636
4152.78.77.64/2952.78.77.65 to 52.78.77.7052.78.77.716
4252.78.77.72/2952.78.77.73 to 52.78.77.7852.78.77.796
4352.78.77.80/2952.78.77.81 to 52.78.77.8652.78.77.876
4452.78.77.88/2952.78.77.89 to 52.78.77.9452.78.77.956
4552.78.77.96/2952.78.77.97 to 52.78.77.10252.78.77.1036
4652.78.77.104/2952.78.77.105 to 52.78.77.11052.78.77.1116
4752.78.77.112/2952.78.77.113 to 52.78.77.11852.78.77.1196
4852.78.77.120/2952.78.77.121 to 52.78.77.12652.78.77.1276
4952.78.77.128/2952.78.77.129 to 52.78.77.13452.78.77.1356
5052.78.77.136/2952.78.77.137 to 52.78.77.14252.78.77.1436
5152.78.77.144/2952.78.77.145 to 52.78.77.15052.78.77.1516
5252.78.77.152/2952.78.77.153 to 52.78.77.15852.78.77.1596
5352.78.77.160/2952.78.77.161 to 52.78.77.16652.78.77.1676
5452.78.77.168/2952.78.77.169 to 52.78.77.17452.78.77.1756
5552.78.77.176/2952.78.77.177 to 52.78.77.18252.78.77.1836
5652.78.77.184/2952.78.77.185 to 52.78.77.19052.78.77.1916
5752.78.77.192/2952.78.77.193 to 52.78.77.19852.78.77.1996
5852.78.77.200/2952.78.77.201 to 52.78.77.20652.78.77.2076
5952.78.77.208/2952.78.77.209 to 52.78.77.21452.78.77.2156
6052.78.77.216/2952.78.77.217 to 52.78.77.22252.78.77.2236
6152.78.77.224/2952.78.77.225 to 52.78.77.23052.78.77.2316
6252.78.77.232/2952.78.77.233 to 52.78.77.23852.78.77.2396
6352.78.77.240/2952.78.77.241 to 52.78.77.24652.78.77.2476
6452.78.77.248/2952.78.77.249 to 52.78.77.25452.78.77.2556
6552.78.78.0/2952.78.78.1 to 52.78.78.652.78.78.76
6652.78.78.8/2952.78.78.9 to 52.78.78.1452.78.78.156
6752.78.78.16/2952.78.78.17 to 52.78.78.2252.78.78.236
6852.78.78.24/2952.78.78.25 to 52.78.78.3052.78.78.316
6952.78.78.32/2952.78.78.33 to 52.78.78.3852.78.78.396
7052.78.78.40/2952.78.78.41 to 52.78.78.4652.78.78.476
7152.78.78.48/2952.78.78.49 to 52.78.78.5452.78.78.556
7252.78.78.56/2952.78.78.57 to 52.78.78.6252.78.78.636
7352.78.78.64/2952.78.78.65 to 52.78.78.7052.78.78.716
7452.78.78.72/2952.78.78.73 to 52.78.78.7852.78.78.796
7552.78.78.80/2952.78.78.81 to 52.78.78.8652.78.78.876
7652.78.78.88/2952.78.78.89 to 52.78.78.9452.78.78.956
7752.78.78.96/2952.78.78.97 to 52.78.78.10252.78.78.1036
7852.78.78.104/2952.78.78.105 to 52.78.78.11052.78.78.1116
7952.78.78.112/2952.78.78.113 to 52.78.78.11852.78.78.1196
8052.78.78.120/2952.78.78.121 to 52.78.78.12652.78.78.1276
8152.78.78.128/2952.78.78.129 to 52.78.78.13452.78.78.1356
8252.78.78.136/2952.78.78.137 to 52.78.78.14252.78.78.1436
8352.78.78.144/2952.78.78.145 to 52.78.78.15052.78.78.1516
8452.78.78.152/2952.78.78.153 to 52.78.78.15852.78.78.1596
8552.78.78.160/2952.78.78.161 to 52.78.78.16652.78.78.1676
8652.78.78.168/2952.78.78.169 to 52.78.78.17452.78.78.1756
8752.78.78.176/2952.78.78.177 to 52.78.78.18252.78.78.1836
8852.78.78.184/2952.78.78.185 to 52.78.78.19052.78.78.1916
8952.78.78.192/2952.78.78.193 to 52.78.78.19852.78.78.1996
9052.78.78.200/2952.78.78.201 to 52.78.78.20652.78.78.2076
9152.78.78.208/2952.78.78.209 to 52.78.78.21452.78.78.2156
9252.78.78.216/2952.78.78.217 to 52.78.78.22252.78.78.2236
9352.78.78.224/2952.78.78.225 to 52.78.78.23052.78.78.2316
9452.78.78.232/2952.78.78.233 to 52.78.78.23852.78.78.2396
9552.78.78.240/2952.78.78.241 to 52.78.78.24652.78.78.2476
9652.78.78.248/2952.78.78.249 to 52.78.78.25452.78.78.2556
9752.78.79.0/2952.78.79.1 to 52.78.79.652.78.79.76
9852.78.79.8/2952.78.79.9 to 52.78.79.1452.78.79.156
9952.78.79.16/2952.78.79.17 to 52.78.79.2252.78.79.236
10052.78.79.24/2952.78.79.25 to 52.78.79.3052.78.79.316
10152.78.79.32/2952.78.79.33 to 52.78.79.3852.78.79.396
10252.78.79.40/2952.78.79.41 to 52.78.79.4652.78.79.476
10352.78.79.48/2952.78.79.49 to 52.78.79.5452.78.79.556
10452.78.79.56/2952.78.79.57 to 52.78.79.6252.78.79.636
10552.78.79.64/2952.78.79.65 to 52.78.79.7052.78.79.716
10652.78.79.72/2952.78.79.73 to 52.78.79.7852.78.79.796
10752.78.79.80/2952.78.79.81 to 52.78.79.8652.78.79.876
10852.78.79.88/2952.78.79.89 to 52.78.79.9452.78.79.956
10952.78.79.96/2952.78.79.97 to 52.78.79.10252.78.79.1036
11052.78.79.104/2952.78.79.105 to 52.78.79.11052.78.79.1116
11152.78.79.112/2952.78.79.113 to 52.78.79.11852.78.79.1196
11252.78.79.120/2952.78.79.121 to 52.78.79.12652.78.79.1276
11352.78.79.128/2952.78.79.129 to 52.78.79.13452.78.79.1356
11452.78.79.136/2952.78.79.137 to 52.78.79.14252.78.79.1436
11552.78.79.144/2952.78.79.145 to 52.78.79.15052.78.79.1516
11652.78.79.152/2952.78.79.153 to 52.78.79.15852.78.79.1596
11752.78.79.160/2952.78.79.161 to 52.78.79.16652.78.79.1676
11852.78.79.168/2952.78.79.169 to 52.78.79.17452.78.79.1756
11952.78.79.176/2952.78.79.177 to 52.78.79.18252.78.79.1836
12052.78.79.184/2952.78.79.185 to 52.78.79.19052.78.79.1916
12152.78.79.192/2952.78.79.193 to 52.78.79.19852.78.79.1996
12252.78.79.200/2952.78.79.201 to 52.78.79.20652.78.79.2076
12352.78.79.208/2952.78.79.209 to 52.78.79.21452.78.79.2156
12452.78.79.216/2952.78.79.217 to 52.78.79.22252.78.79.2236
12552.78.79.224/2952.78.79.225 to 52.78.79.23052.78.79.2316
12652.78.79.232/2952.78.79.233 to 52.78.79.23852.78.79.2396
12752.78.79.240/2952.78.79.241 to 52.78.79.24652.78.79.2476
12852.78.79.248/2952.78.79.249 to 52.78.79.25452.78.79.2556

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.