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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.

Network41.22.32.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
41.22.32.0
Broadcast address
41.22.63.255
First usable
41.22.32.1
Last usable
41.22.63.254
Usable hosts
8,190 (8,192 less the network and broadcast addresses)
Subnet mask
255.255.224.0
Wildcard mask
0.0.31.255 (Cisco ACLs, OSPF)
Prefix length
/19
Type
Public public
Old class
A (default /8)
As numbers
Hex 29162000 · Integer 689315840 to 689324031
Reverse DNS zones
32.22.41.in-addr.arpa
33.22.41.in-addr.arpa
34.22.41.in-addr.arpa
35.22.41.in-addr.arpa
36.22.41.in-addr.arpa
37.22.41.in-addr.arpa
38.22.41.in-addr.arpa
39.22.41.in-addr.arpa
40.22.41.in-addr.arpa
41.22.41.in-addr.arpa
42.22.41.in-addr.arpa
43.22.41.in-addr.arpa
44.22.41.in-addr.arpa
45.22.41.in-addr.arpa
46.22.41.in-addr.arpa
47.22.41.in-addr.arpa
and 16 more
/19 is not on a 8-bit boundary, so it takes 32 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00101001.00010110.00100000.0000000041.22.32.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network00101001.00010110.00100000.0000000041.22.32.0
Broadcast00101001.00010110.00111111.1111111141.22.63.255
Split into smaller subnets/26
/20 (2)/21 (4)/22 (8)/23 (16)/24 (32)/25 (64)/26 (128)/27 (256)/28 (512)/29 (1,024)/30 (2,048)/31 (4,096)

41.22.32.0/19 makes 128 subnets of /26.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
141.22.32.0/2641.22.32.1 to 41.22.32.6241.22.32.6362
241.22.32.64/2641.22.32.65 to 41.22.32.12641.22.32.12762
341.22.32.128/2641.22.32.129 to 41.22.32.19041.22.32.19162
441.22.32.192/2641.22.32.193 to 41.22.32.25441.22.32.25562
541.22.33.0/2641.22.33.1 to 41.22.33.6241.22.33.6362
641.22.33.64/2641.22.33.65 to 41.22.33.12641.22.33.12762
741.22.33.128/2641.22.33.129 to 41.22.33.19041.22.33.19162
841.22.33.192/2641.22.33.193 to 41.22.33.25441.22.33.25562
941.22.34.0/2641.22.34.1 to 41.22.34.6241.22.34.6362
1041.22.34.64/2641.22.34.65 to 41.22.34.12641.22.34.12762
1141.22.34.128/2641.22.34.129 to 41.22.34.19041.22.34.19162
1241.22.34.192/2641.22.34.193 to 41.22.34.25441.22.34.25562
1341.22.35.0/2641.22.35.1 to 41.22.35.6241.22.35.6362
1441.22.35.64/2641.22.35.65 to 41.22.35.12641.22.35.12762
1541.22.35.128/2641.22.35.129 to 41.22.35.19041.22.35.19162
1641.22.35.192/2641.22.35.193 to 41.22.35.25441.22.35.25562
1741.22.36.0/2641.22.36.1 to 41.22.36.6241.22.36.6362
1841.22.36.64/2641.22.36.65 to 41.22.36.12641.22.36.12762
1941.22.36.128/2641.22.36.129 to 41.22.36.19041.22.36.19162
2041.22.36.192/2641.22.36.193 to 41.22.36.25441.22.36.25562
2141.22.37.0/2641.22.37.1 to 41.22.37.6241.22.37.6362
2241.22.37.64/2641.22.37.65 to 41.22.37.12641.22.37.12762
2341.22.37.128/2641.22.37.129 to 41.22.37.19041.22.37.19162
2441.22.37.192/2641.22.37.193 to 41.22.37.25441.22.37.25562
2541.22.38.0/2641.22.38.1 to 41.22.38.6241.22.38.6362
2641.22.38.64/2641.22.38.65 to 41.22.38.12641.22.38.12762
2741.22.38.128/2641.22.38.129 to 41.22.38.19041.22.38.19162
2841.22.38.192/2641.22.38.193 to 41.22.38.25441.22.38.25562
2941.22.39.0/2641.22.39.1 to 41.22.39.6241.22.39.6362
3041.22.39.64/2641.22.39.65 to 41.22.39.12641.22.39.12762
3141.22.39.128/2641.22.39.129 to 41.22.39.19041.22.39.19162
3241.22.39.192/2641.22.39.193 to 41.22.39.25441.22.39.25562
3341.22.40.0/2641.22.40.1 to 41.22.40.6241.22.40.6362
3441.22.40.64/2641.22.40.65 to 41.22.40.12641.22.40.12762
3541.22.40.128/2641.22.40.129 to 41.22.40.19041.22.40.19162
3641.22.40.192/2641.22.40.193 to 41.22.40.25441.22.40.25562
3741.22.41.0/2641.22.41.1 to 41.22.41.6241.22.41.6362
3841.22.41.64/2641.22.41.65 to 41.22.41.12641.22.41.12762
3941.22.41.128/2641.22.41.129 to 41.22.41.19041.22.41.19162
4041.22.41.192/2641.22.41.193 to 41.22.41.25441.22.41.25562
4141.22.42.0/2641.22.42.1 to 41.22.42.6241.22.42.6362
4241.22.42.64/2641.22.42.65 to 41.22.42.12641.22.42.12762
4341.22.42.128/2641.22.42.129 to 41.22.42.19041.22.42.19162
4441.22.42.192/2641.22.42.193 to 41.22.42.25441.22.42.25562
4541.22.43.0/2641.22.43.1 to 41.22.43.6241.22.43.6362
4641.22.43.64/2641.22.43.65 to 41.22.43.12641.22.43.12762
4741.22.43.128/2641.22.43.129 to 41.22.43.19041.22.43.19162
4841.22.43.192/2641.22.43.193 to 41.22.43.25441.22.43.25562
4941.22.44.0/2641.22.44.1 to 41.22.44.6241.22.44.6362
5041.22.44.64/2641.22.44.65 to 41.22.44.12641.22.44.12762
5141.22.44.128/2641.22.44.129 to 41.22.44.19041.22.44.19162
5241.22.44.192/2641.22.44.193 to 41.22.44.25441.22.44.25562
5341.22.45.0/2641.22.45.1 to 41.22.45.6241.22.45.6362
5441.22.45.64/2641.22.45.65 to 41.22.45.12641.22.45.12762
5541.22.45.128/2641.22.45.129 to 41.22.45.19041.22.45.19162
5641.22.45.192/2641.22.45.193 to 41.22.45.25441.22.45.25562
5741.22.46.0/2641.22.46.1 to 41.22.46.6241.22.46.6362
5841.22.46.64/2641.22.46.65 to 41.22.46.12641.22.46.12762
5941.22.46.128/2641.22.46.129 to 41.22.46.19041.22.46.19162
6041.22.46.192/2641.22.46.193 to 41.22.46.25441.22.46.25562
6141.22.47.0/2641.22.47.1 to 41.22.47.6241.22.47.6362
6241.22.47.64/2641.22.47.65 to 41.22.47.12641.22.47.12762
6341.22.47.128/2641.22.47.129 to 41.22.47.19041.22.47.19162
6441.22.47.192/2641.22.47.193 to 41.22.47.25441.22.47.25562
6541.22.48.0/2641.22.48.1 to 41.22.48.6241.22.48.6362
6641.22.48.64/2641.22.48.65 to 41.22.48.12641.22.48.12762
6741.22.48.128/2641.22.48.129 to 41.22.48.19041.22.48.19162
6841.22.48.192/2641.22.48.193 to 41.22.48.25441.22.48.25562
6941.22.49.0/2641.22.49.1 to 41.22.49.6241.22.49.6362
7041.22.49.64/2641.22.49.65 to 41.22.49.12641.22.49.12762
7141.22.49.128/2641.22.49.129 to 41.22.49.19041.22.49.19162
7241.22.49.192/2641.22.49.193 to 41.22.49.25441.22.49.25562
7341.22.50.0/2641.22.50.1 to 41.22.50.6241.22.50.6362
7441.22.50.64/2641.22.50.65 to 41.22.50.12641.22.50.12762
7541.22.50.128/2641.22.50.129 to 41.22.50.19041.22.50.19162
7641.22.50.192/2641.22.50.193 to 41.22.50.25441.22.50.25562
7741.22.51.0/2641.22.51.1 to 41.22.51.6241.22.51.6362
7841.22.51.64/2641.22.51.65 to 41.22.51.12641.22.51.12762
7941.22.51.128/2641.22.51.129 to 41.22.51.19041.22.51.19162
8041.22.51.192/2641.22.51.193 to 41.22.51.25441.22.51.25562
8141.22.52.0/2641.22.52.1 to 41.22.52.6241.22.52.6362
8241.22.52.64/2641.22.52.65 to 41.22.52.12641.22.52.12762
8341.22.52.128/2641.22.52.129 to 41.22.52.19041.22.52.19162
8441.22.52.192/2641.22.52.193 to 41.22.52.25441.22.52.25562
8541.22.53.0/2641.22.53.1 to 41.22.53.6241.22.53.6362
8641.22.53.64/2641.22.53.65 to 41.22.53.12641.22.53.12762
8741.22.53.128/2641.22.53.129 to 41.22.53.19041.22.53.19162
8841.22.53.192/2641.22.53.193 to 41.22.53.25441.22.53.25562
8941.22.54.0/2641.22.54.1 to 41.22.54.6241.22.54.6362
9041.22.54.64/2641.22.54.65 to 41.22.54.12641.22.54.12762
9141.22.54.128/2641.22.54.129 to 41.22.54.19041.22.54.19162
9241.22.54.192/2641.22.54.193 to 41.22.54.25441.22.54.25562
9341.22.55.0/2641.22.55.1 to 41.22.55.6241.22.55.6362
9441.22.55.64/2641.22.55.65 to 41.22.55.12641.22.55.12762
9541.22.55.128/2641.22.55.129 to 41.22.55.19041.22.55.19162
9641.22.55.192/2641.22.55.193 to 41.22.55.25441.22.55.25562
9741.22.56.0/2641.22.56.1 to 41.22.56.6241.22.56.6362
9841.22.56.64/2641.22.56.65 to 41.22.56.12641.22.56.12762
9941.22.56.128/2641.22.56.129 to 41.22.56.19041.22.56.19162
10041.22.56.192/2641.22.56.193 to 41.22.56.25441.22.56.25562
10141.22.57.0/2641.22.57.1 to 41.22.57.6241.22.57.6362
10241.22.57.64/2641.22.57.65 to 41.22.57.12641.22.57.12762
10341.22.57.128/2641.22.57.129 to 41.22.57.19041.22.57.19162
10441.22.57.192/2641.22.57.193 to 41.22.57.25441.22.57.25562
10541.22.58.0/2641.22.58.1 to 41.22.58.6241.22.58.6362
10641.22.58.64/2641.22.58.65 to 41.22.58.12641.22.58.12762
10741.22.58.128/2641.22.58.129 to 41.22.58.19041.22.58.19162
10841.22.58.192/2641.22.58.193 to 41.22.58.25441.22.58.25562
10941.22.59.0/2641.22.59.1 to 41.22.59.6241.22.59.6362
11041.22.59.64/2641.22.59.65 to 41.22.59.12641.22.59.12762
11141.22.59.128/2641.22.59.129 to 41.22.59.19041.22.59.19162
11241.22.59.192/2641.22.59.193 to 41.22.59.25441.22.59.25562
11341.22.60.0/2641.22.60.1 to 41.22.60.6241.22.60.6362
11441.22.60.64/2641.22.60.65 to 41.22.60.12641.22.60.12762
11541.22.60.128/2641.22.60.129 to 41.22.60.19041.22.60.19162
11641.22.60.192/2641.22.60.193 to 41.22.60.25441.22.60.25562
11741.22.61.0/2641.22.61.1 to 41.22.61.6241.22.61.6362
11841.22.61.64/2641.22.61.65 to 41.22.61.12641.22.61.12762
11941.22.61.128/2641.22.61.129 to 41.22.61.19041.22.61.19162
12041.22.61.192/2641.22.61.193 to 41.22.61.25441.22.61.25562
12141.22.62.0/2641.22.62.1 to 41.22.62.6241.22.62.6362
12241.22.62.64/2641.22.62.65 to 41.22.62.12641.22.62.12762
12341.22.62.128/2641.22.62.129 to 41.22.62.19041.22.62.19162
12441.22.62.192/2641.22.62.193 to 41.22.62.25441.22.62.25562
12541.22.63.0/2641.22.63.1 to 41.22.63.6241.22.63.6362
12641.22.63.64/2641.22.63.65 to 41.22.63.12641.22.63.12762
12741.22.63.128/2641.22.63.129 to 41.22.63.19041.22.63.19162
12841.22.63.192/2641.22.63.193 to 41.22.63.25441.22.63.25562

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.