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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.

Network48.3.52.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
48.3.52.0
Broadcast address
48.3.55.255
First usable
48.3.52.1
Last usable
48.3.55.254
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 30033400 · Integer 805516288 to 805517311
Reverse DNS zones
52.3.48.in-addr.arpa
53.3.48.in-addr.arpa
54.3.48.in-addr.arpa
55.3.48.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
Address00110000.00000011.00110100.0000000048.3.52.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network00110000.00000011.00110100.0000000048.3.52.0
Broadcast00110000.00000011.00110111.1111111148.3.55.255
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)

48.3.52.0/22 makes 128 subnets of /29.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
148.3.52.0/2948.3.52.1 to 48.3.52.648.3.52.76
248.3.52.8/2948.3.52.9 to 48.3.52.1448.3.52.156
348.3.52.16/2948.3.52.17 to 48.3.52.2248.3.52.236
448.3.52.24/2948.3.52.25 to 48.3.52.3048.3.52.316
548.3.52.32/2948.3.52.33 to 48.3.52.3848.3.52.396
648.3.52.40/2948.3.52.41 to 48.3.52.4648.3.52.476
748.3.52.48/2948.3.52.49 to 48.3.52.5448.3.52.556
848.3.52.56/2948.3.52.57 to 48.3.52.6248.3.52.636
948.3.52.64/2948.3.52.65 to 48.3.52.7048.3.52.716
1048.3.52.72/2948.3.52.73 to 48.3.52.7848.3.52.796
1148.3.52.80/2948.3.52.81 to 48.3.52.8648.3.52.876
1248.3.52.88/2948.3.52.89 to 48.3.52.9448.3.52.956
1348.3.52.96/2948.3.52.97 to 48.3.52.10248.3.52.1036
1448.3.52.104/2948.3.52.105 to 48.3.52.11048.3.52.1116
1548.3.52.112/2948.3.52.113 to 48.3.52.11848.3.52.1196
1648.3.52.120/2948.3.52.121 to 48.3.52.12648.3.52.1276
1748.3.52.128/2948.3.52.129 to 48.3.52.13448.3.52.1356
1848.3.52.136/2948.3.52.137 to 48.3.52.14248.3.52.1436
1948.3.52.144/2948.3.52.145 to 48.3.52.15048.3.52.1516
2048.3.52.152/2948.3.52.153 to 48.3.52.15848.3.52.1596
2148.3.52.160/2948.3.52.161 to 48.3.52.16648.3.52.1676
2248.3.52.168/2948.3.52.169 to 48.3.52.17448.3.52.1756
2348.3.52.176/2948.3.52.177 to 48.3.52.18248.3.52.1836
2448.3.52.184/2948.3.52.185 to 48.3.52.19048.3.52.1916
2548.3.52.192/2948.3.52.193 to 48.3.52.19848.3.52.1996
2648.3.52.200/2948.3.52.201 to 48.3.52.20648.3.52.2076
2748.3.52.208/2948.3.52.209 to 48.3.52.21448.3.52.2156
2848.3.52.216/2948.3.52.217 to 48.3.52.22248.3.52.2236
2948.3.52.224/2948.3.52.225 to 48.3.52.23048.3.52.2316
3048.3.52.232/2948.3.52.233 to 48.3.52.23848.3.52.2396
3148.3.52.240/2948.3.52.241 to 48.3.52.24648.3.52.2476
3248.3.52.248/2948.3.52.249 to 48.3.52.25448.3.52.2556
3348.3.53.0/2948.3.53.1 to 48.3.53.648.3.53.76
3448.3.53.8/2948.3.53.9 to 48.3.53.1448.3.53.156
3548.3.53.16/2948.3.53.17 to 48.3.53.2248.3.53.236
3648.3.53.24/2948.3.53.25 to 48.3.53.3048.3.53.316
3748.3.53.32/2948.3.53.33 to 48.3.53.3848.3.53.396
3848.3.53.40/2948.3.53.41 to 48.3.53.4648.3.53.476
3948.3.53.48/2948.3.53.49 to 48.3.53.5448.3.53.556
4048.3.53.56/2948.3.53.57 to 48.3.53.6248.3.53.636
4148.3.53.64/2948.3.53.65 to 48.3.53.7048.3.53.716
4248.3.53.72/2948.3.53.73 to 48.3.53.7848.3.53.796
4348.3.53.80/2948.3.53.81 to 48.3.53.8648.3.53.876
4448.3.53.88/2948.3.53.89 to 48.3.53.9448.3.53.956
4548.3.53.96/2948.3.53.97 to 48.3.53.10248.3.53.1036
4648.3.53.104/2948.3.53.105 to 48.3.53.11048.3.53.1116
4748.3.53.112/2948.3.53.113 to 48.3.53.11848.3.53.1196
4848.3.53.120/2948.3.53.121 to 48.3.53.12648.3.53.1276
4948.3.53.128/2948.3.53.129 to 48.3.53.13448.3.53.1356
5048.3.53.136/2948.3.53.137 to 48.3.53.14248.3.53.1436
5148.3.53.144/2948.3.53.145 to 48.3.53.15048.3.53.1516
5248.3.53.152/2948.3.53.153 to 48.3.53.15848.3.53.1596
5348.3.53.160/2948.3.53.161 to 48.3.53.16648.3.53.1676
5448.3.53.168/2948.3.53.169 to 48.3.53.17448.3.53.1756
5548.3.53.176/2948.3.53.177 to 48.3.53.18248.3.53.1836
5648.3.53.184/2948.3.53.185 to 48.3.53.19048.3.53.1916
5748.3.53.192/2948.3.53.193 to 48.3.53.19848.3.53.1996
5848.3.53.200/2948.3.53.201 to 48.3.53.20648.3.53.2076
5948.3.53.208/2948.3.53.209 to 48.3.53.21448.3.53.2156
6048.3.53.216/2948.3.53.217 to 48.3.53.22248.3.53.2236
6148.3.53.224/2948.3.53.225 to 48.3.53.23048.3.53.2316
6248.3.53.232/2948.3.53.233 to 48.3.53.23848.3.53.2396
6348.3.53.240/2948.3.53.241 to 48.3.53.24648.3.53.2476
6448.3.53.248/2948.3.53.249 to 48.3.53.25448.3.53.2556
6548.3.54.0/2948.3.54.1 to 48.3.54.648.3.54.76
6648.3.54.8/2948.3.54.9 to 48.3.54.1448.3.54.156
6748.3.54.16/2948.3.54.17 to 48.3.54.2248.3.54.236
6848.3.54.24/2948.3.54.25 to 48.3.54.3048.3.54.316
6948.3.54.32/2948.3.54.33 to 48.3.54.3848.3.54.396
7048.3.54.40/2948.3.54.41 to 48.3.54.4648.3.54.476
7148.3.54.48/2948.3.54.49 to 48.3.54.5448.3.54.556
7248.3.54.56/2948.3.54.57 to 48.3.54.6248.3.54.636
7348.3.54.64/2948.3.54.65 to 48.3.54.7048.3.54.716
7448.3.54.72/2948.3.54.73 to 48.3.54.7848.3.54.796
7548.3.54.80/2948.3.54.81 to 48.3.54.8648.3.54.876
7648.3.54.88/2948.3.54.89 to 48.3.54.9448.3.54.956
7748.3.54.96/2948.3.54.97 to 48.3.54.10248.3.54.1036
7848.3.54.104/2948.3.54.105 to 48.3.54.11048.3.54.1116
7948.3.54.112/2948.3.54.113 to 48.3.54.11848.3.54.1196
8048.3.54.120/2948.3.54.121 to 48.3.54.12648.3.54.1276
8148.3.54.128/2948.3.54.129 to 48.3.54.13448.3.54.1356
8248.3.54.136/2948.3.54.137 to 48.3.54.14248.3.54.1436
8348.3.54.144/2948.3.54.145 to 48.3.54.15048.3.54.1516
8448.3.54.152/2948.3.54.153 to 48.3.54.15848.3.54.1596
8548.3.54.160/2948.3.54.161 to 48.3.54.16648.3.54.1676
8648.3.54.168/2948.3.54.169 to 48.3.54.17448.3.54.1756
8748.3.54.176/2948.3.54.177 to 48.3.54.18248.3.54.1836
8848.3.54.184/2948.3.54.185 to 48.3.54.19048.3.54.1916
8948.3.54.192/2948.3.54.193 to 48.3.54.19848.3.54.1996
9048.3.54.200/2948.3.54.201 to 48.3.54.20648.3.54.2076
9148.3.54.208/2948.3.54.209 to 48.3.54.21448.3.54.2156
9248.3.54.216/2948.3.54.217 to 48.3.54.22248.3.54.2236
9348.3.54.224/2948.3.54.225 to 48.3.54.23048.3.54.2316
9448.3.54.232/2948.3.54.233 to 48.3.54.23848.3.54.2396
9548.3.54.240/2948.3.54.241 to 48.3.54.24648.3.54.2476
9648.3.54.248/2948.3.54.249 to 48.3.54.25448.3.54.2556
9748.3.55.0/2948.3.55.1 to 48.3.55.648.3.55.76
9848.3.55.8/2948.3.55.9 to 48.3.55.1448.3.55.156
9948.3.55.16/2948.3.55.17 to 48.3.55.2248.3.55.236
10048.3.55.24/2948.3.55.25 to 48.3.55.3048.3.55.316
10148.3.55.32/2948.3.55.33 to 48.3.55.3848.3.55.396
10248.3.55.40/2948.3.55.41 to 48.3.55.4648.3.55.476
10348.3.55.48/2948.3.55.49 to 48.3.55.5448.3.55.556
10448.3.55.56/2948.3.55.57 to 48.3.55.6248.3.55.636
10548.3.55.64/2948.3.55.65 to 48.3.55.7048.3.55.716
10648.3.55.72/2948.3.55.73 to 48.3.55.7848.3.55.796
10748.3.55.80/2948.3.55.81 to 48.3.55.8648.3.55.876
10848.3.55.88/2948.3.55.89 to 48.3.55.9448.3.55.956
10948.3.55.96/2948.3.55.97 to 48.3.55.10248.3.55.1036
11048.3.55.104/2948.3.55.105 to 48.3.55.11048.3.55.1116
11148.3.55.112/2948.3.55.113 to 48.3.55.11848.3.55.1196
11248.3.55.120/2948.3.55.121 to 48.3.55.12648.3.55.1276
11348.3.55.128/2948.3.55.129 to 48.3.55.13448.3.55.1356
11448.3.55.136/2948.3.55.137 to 48.3.55.14248.3.55.1436
11548.3.55.144/2948.3.55.145 to 48.3.55.15048.3.55.1516
11648.3.55.152/2948.3.55.153 to 48.3.55.15848.3.55.1596
11748.3.55.160/2948.3.55.161 to 48.3.55.16648.3.55.1676
11848.3.55.168/2948.3.55.169 to 48.3.55.17448.3.55.1756
11948.3.55.176/2948.3.55.177 to 48.3.55.18248.3.55.1836
12048.3.55.184/2948.3.55.185 to 48.3.55.19048.3.55.1916
12148.3.55.192/2948.3.55.193 to 48.3.55.19848.3.55.1996
12248.3.55.200/2948.3.55.201 to 48.3.55.20648.3.55.2076
12348.3.55.208/2948.3.55.209 to 48.3.55.21448.3.55.2156
12448.3.55.216/2948.3.55.217 to 48.3.55.22248.3.55.2236
12548.3.55.224/2948.3.55.225 to 48.3.55.23048.3.55.2316
12648.3.55.232/2948.3.55.233 to 48.3.55.23848.3.55.2396
12748.3.55.240/2948.3.55.241 to 48.3.55.24648.3.55.2476
12848.3.55.248/2948.3.55.249 to 48.3.55.25448.3.55.2556

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.