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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.

Network225.0.92.0/22
Usable hosts1,022
Subnet mask255.255.252.0
Addresses1,024
Network address
225.0.92.0
Broadcast address
225.0.95.255
First usable
225.0.92.1
Last usable
225.0.95.254
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
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E1005C00 · Integer 3774897152 to 3774898175
Reverse DNS zones
92.0.225.in-addr.arpa
93.0.225.in-addr.arpa
94.0.225.in-addr.arpa
95.0.225.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
Address11100001.00000000.01011100.00000000225.0.92.0
Subnet mask11111111.11111111.11111100.00000000255.255.252.0
Network11100001.00000000.01011100.00000000225.0.92.0
Broadcast11100001.00000000.01011111.11111111225.0.95.255
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)

225.0.92.0/22 makes 128 subnets of /29.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1225.0.92.0/29225.0.92.1 to 225.0.92.6225.0.92.76
2225.0.92.8/29225.0.92.9 to 225.0.92.14225.0.92.156
3225.0.92.16/29225.0.92.17 to 225.0.92.22225.0.92.236
4225.0.92.24/29225.0.92.25 to 225.0.92.30225.0.92.316
5225.0.92.32/29225.0.92.33 to 225.0.92.38225.0.92.396
6225.0.92.40/29225.0.92.41 to 225.0.92.46225.0.92.476
7225.0.92.48/29225.0.92.49 to 225.0.92.54225.0.92.556
8225.0.92.56/29225.0.92.57 to 225.0.92.62225.0.92.636
9225.0.92.64/29225.0.92.65 to 225.0.92.70225.0.92.716
10225.0.92.72/29225.0.92.73 to 225.0.92.78225.0.92.796
11225.0.92.80/29225.0.92.81 to 225.0.92.86225.0.92.876
12225.0.92.88/29225.0.92.89 to 225.0.92.94225.0.92.956
13225.0.92.96/29225.0.92.97 to 225.0.92.102225.0.92.1036
14225.0.92.104/29225.0.92.105 to 225.0.92.110225.0.92.1116
15225.0.92.112/29225.0.92.113 to 225.0.92.118225.0.92.1196
16225.0.92.120/29225.0.92.121 to 225.0.92.126225.0.92.1276
17225.0.92.128/29225.0.92.129 to 225.0.92.134225.0.92.1356
18225.0.92.136/29225.0.92.137 to 225.0.92.142225.0.92.1436
19225.0.92.144/29225.0.92.145 to 225.0.92.150225.0.92.1516
20225.0.92.152/29225.0.92.153 to 225.0.92.158225.0.92.1596
21225.0.92.160/29225.0.92.161 to 225.0.92.166225.0.92.1676
22225.0.92.168/29225.0.92.169 to 225.0.92.174225.0.92.1756
23225.0.92.176/29225.0.92.177 to 225.0.92.182225.0.92.1836
24225.0.92.184/29225.0.92.185 to 225.0.92.190225.0.92.1916
25225.0.92.192/29225.0.92.193 to 225.0.92.198225.0.92.1996
26225.0.92.200/29225.0.92.201 to 225.0.92.206225.0.92.2076
27225.0.92.208/29225.0.92.209 to 225.0.92.214225.0.92.2156
28225.0.92.216/29225.0.92.217 to 225.0.92.222225.0.92.2236
29225.0.92.224/29225.0.92.225 to 225.0.92.230225.0.92.2316
30225.0.92.232/29225.0.92.233 to 225.0.92.238225.0.92.2396
31225.0.92.240/29225.0.92.241 to 225.0.92.246225.0.92.2476
32225.0.92.248/29225.0.92.249 to 225.0.92.254225.0.92.2556
33225.0.93.0/29225.0.93.1 to 225.0.93.6225.0.93.76
34225.0.93.8/29225.0.93.9 to 225.0.93.14225.0.93.156
35225.0.93.16/29225.0.93.17 to 225.0.93.22225.0.93.236
36225.0.93.24/29225.0.93.25 to 225.0.93.30225.0.93.316
37225.0.93.32/29225.0.93.33 to 225.0.93.38225.0.93.396
38225.0.93.40/29225.0.93.41 to 225.0.93.46225.0.93.476
39225.0.93.48/29225.0.93.49 to 225.0.93.54225.0.93.556
40225.0.93.56/29225.0.93.57 to 225.0.93.62225.0.93.636
41225.0.93.64/29225.0.93.65 to 225.0.93.70225.0.93.716
42225.0.93.72/29225.0.93.73 to 225.0.93.78225.0.93.796
43225.0.93.80/29225.0.93.81 to 225.0.93.86225.0.93.876
44225.0.93.88/29225.0.93.89 to 225.0.93.94225.0.93.956
45225.0.93.96/29225.0.93.97 to 225.0.93.102225.0.93.1036
46225.0.93.104/29225.0.93.105 to 225.0.93.110225.0.93.1116
47225.0.93.112/29225.0.93.113 to 225.0.93.118225.0.93.1196
48225.0.93.120/29225.0.93.121 to 225.0.93.126225.0.93.1276
49225.0.93.128/29225.0.93.129 to 225.0.93.134225.0.93.1356
50225.0.93.136/29225.0.93.137 to 225.0.93.142225.0.93.1436
51225.0.93.144/29225.0.93.145 to 225.0.93.150225.0.93.1516
52225.0.93.152/29225.0.93.153 to 225.0.93.158225.0.93.1596
53225.0.93.160/29225.0.93.161 to 225.0.93.166225.0.93.1676
54225.0.93.168/29225.0.93.169 to 225.0.93.174225.0.93.1756
55225.0.93.176/29225.0.93.177 to 225.0.93.182225.0.93.1836
56225.0.93.184/29225.0.93.185 to 225.0.93.190225.0.93.1916
57225.0.93.192/29225.0.93.193 to 225.0.93.198225.0.93.1996
58225.0.93.200/29225.0.93.201 to 225.0.93.206225.0.93.2076
59225.0.93.208/29225.0.93.209 to 225.0.93.214225.0.93.2156
60225.0.93.216/29225.0.93.217 to 225.0.93.222225.0.93.2236
61225.0.93.224/29225.0.93.225 to 225.0.93.230225.0.93.2316
62225.0.93.232/29225.0.93.233 to 225.0.93.238225.0.93.2396
63225.0.93.240/29225.0.93.241 to 225.0.93.246225.0.93.2476
64225.0.93.248/29225.0.93.249 to 225.0.93.254225.0.93.2556
65225.0.94.0/29225.0.94.1 to 225.0.94.6225.0.94.76
66225.0.94.8/29225.0.94.9 to 225.0.94.14225.0.94.156
67225.0.94.16/29225.0.94.17 to 225.0.94.22225.0.94.236
68225.0.94.24/29225.0.94.25 to 225.0.94.30225.0.94.316
69225.0.94.32/29225.0.94.33 to 225.0.94.38225.0.94.396
70225.0.94.40/29225.0.94.41 to 225.0.94.46225.0.94.476
71225.0.94.48/29225.0.94.49 to 225.0.94.54225.0.94.556
72225.0.94.56/29225.0.94.57 to 225.0.94.62225.0.94.636
73225.0.94.64/29225.0.94.65 to 225.0.94.70225.0.94.716
74225.0.94.72/29225.0.94.73 to 225.0.94.78225.0.94.796
75225.0.94.80/29225.0.94.81 to 225.0.94.86225.0.94.876
76225.0.94.88/29225.0.94.89 to 225.0.94.94225.0.94.956
77225.0.94.96/29225.0.94.97 to 225.0.94.102225.0.94.1036
78225.0.94.104/29225.0.94.105 to 225.0.94.110225.0.94.1116
79225.0.94.112/29225.0.94.113 to 225.0.94.118225.0.94.1196
80225.0.94.120/29225.0.94.121 to 225.0.94.126225.0.94.1276
81225.0.94.128/29225.0.94.129 to 225.0.94.134225.0.94.1356
82225.0.94.136/29225.0.94.137 to 225.0.94.142225.0.94.1436
83225.0.94.144/29225.0.94.145 to 225.0.94.150225.0.94.1516
84225.0.94.152/29225.0.94.153 to 225.0.94.158225.0.94.1596
85225.0.94.160/29225.0.94.161 to 225.0.94.166225.0.94.1676
86225.0.94.168/29225.0.94.169 to 225.0.94.174225.0.94.1756
87225.0.94.176/29225.0.94.177 to 225.0.94.182225.0.94.1836
88225.0.94.184/29225.0.94.185 to 225.0.94.190225.0.94.1916
89225.0.94.192/29225.0.94.193 to 225.0.94.198225.0.94.1996
90225.0.94.200/29225.0.94.201 to 225.0.94.206225.0.94.2076
91225.0.94.208/29225.0.94.209 to 225.0.94.214225.0.94.2156
92225.0.94.216/29225.0.94.217 to 225.0.94.222225.0.94.2236
93225.0.94.224/29225.0.94.225 to 225.0.94.230225.0.94.2316
94225.0.94.232/29225.0.94.233 to 225.0.94.238225.0.94.2396
95225.0.94.240/29225.0.94.241 to 225.0.94.246225.0.94.2476
96225.0.94.248/29225.0.94.249 to 225.0.94.254225.0.94.2556
97225.0.95.0/29225.0.95.1 to 225.0.95.6225.0.95.76
98225.0.95.8/29225.0.95.9 to 225.0.95.14225.0.95.156
99225.0.95.16/29225.0.95.17 to 225.0.95.22225.0.95.236
100225.0.95.24/29225.0.95.25 to 225.0.95.30225.0.95.316
101225.0.95.32/29225.0.95.33 to 225.0.95.38225.0.95.396
102225.0.95.40/29225.0.95.41 to 225.0.95.46225.0.95.476
103225.0.95.48/29225.0.95.49 to 225.0.95.54225.0.95.556
104225.0.95.56/29225.0.95.57 to 225.0.95.62225.0.95.636
105225.0.95.64/29225.0.95.65 to 225.0.95.70225.0.95.716
106225.0.95.72/29225.0.95.73 to 225.0.95.78225.0.95.796
107225.0.95.80/29225.0.95.81 to 225.0.95.86225.0.95.876
108225.0.95.88/29225.0.95.89 to 225.0.95.94225.0.95.956
109225.0.95.96/29225.0.95.97 to 225.0.95.102225.0.95.1036
110225.0.95.104/29225.0.95.105 to 225.0.95.110225.0.95.1116
111225.0.95.112/29225.0.95.113 to 225.0.95.118225.0.95.1196
112225.0.95.120/29225.0.95.121 to 225.0.95.126225.0.95.1276
113225.0.95.128/29225.0.95.129 to 225.0.95.134225.0.95.1356
114225.0.95.136/29225.0.95.137 to 225.0.95.142225.0.95.1436
115225.0.95.144/29225.0.95.145 to 225.0.95.150225.0.95.1516
116225.0.95.152/29225.0.95.153 to 225.0.95.158225.0.95.1596
117225.0.95.160/29225.0.95.161 to 225.0.95.166225.0.95.1676
118225.0.95.168/29225.0.95.169 to 225.0.95.174225.0.95.1756
119225.0.95.176/29225.0.95.177 to 225.0.95.182225.0.95.1836
120225.0.95.184/29225.0.95.185 to 225.0.95.190225.0.95.1916
121225.0.95.192/29225.0.95.193 to 225.0.95.198225.0.95.1996
122225.0.95.200/29225.0.95.201 to 225.0.95.206225.0.95.2076
123225.0.95.208/29225.0.95.209 to 225.0.95.214225.0.95.2156
124225.0.95.216/29225.0.95.217 to 225.0.95.222225.0.95.2236
125225.0.95.224/29225.0.95.225 to 225.0.95.230225.0.95.2316
126225.0.95.232/29225.0.95.233 to 225.0.95.238225.0.95.2396
127225.0.95.240/29225.0.95.241 to 225.0.95.246225.0.95.2476
128225.0.95.248/29225.0.95.249 to 225.0.95.254225.0.95.2556

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.