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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.

Network57.3.96.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
57.3.96.0
Broadcast address
57.3.127.255
First usable
57.3.96.1
Last usable
57.3.127.254
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 39036000 · Integer 956522496 to 956530687
Reverse DNS zones
96.3.57.in-addr.arpa
97.3.57.in-addr.arpa
98.3.57.in-addr.arpa
99.3.57.in-addr.arpa
100.3.57.in-addr.arpa
101.3.57.in-addr.arpa
102.3.57.in-addr.arpa
103.3.57.in-addr.arpa
104.3.57.in-addr.arpa
105.3.57.in-addr.arpa
106.3.57.in-addr.arpa
107.3.57.in-addr.arpa
108.3.57.in-addr.arpa
109.3.57.in-addr.arpa
110.3.57.in-addr.arpa
111.3.57.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
Address00111001.00000011.01100000.0000000057.3.96.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network00111001.00000011.01100000.0000000057.3.96.0
Broadcast00111001.00000011.01111111.1111111157.3.127.255
Split into smaller subnets/26

57.3.96.0/19 makes 128 subnets of /26.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
157.3.96.0/2657.3.96.1 to 57.3.96.6257.3.96.6362
257.3.96.64/2657.3.96.65 to 57.3.96.12657.3.96.12762
357.3.96.128/2657.3.96.129 to 57.3.96.19057.3.96.19162
457.3.96.192/2657.3.96.193 to 57.3.96.25457.3.96.25562
557.3.97.0/2657.3.97.1 to 57.3.97.6257.3.97.6362
657.3.97.64/2657.3.97.65 to 57.3.97.12657.3.97.12762
757.3.97.128/2657.3.97.129 to 57.3.97.19057.3.97.19162
857.3.97.192/2657.3.97.193 to 57.3.97.25457.3.97.25562
957.3.98.0/2657.3.98.1 to 57.3.98.6257.3.98.6362
1057.3.98.64/2657.3.98.65 to 57.3.98.12657.3.98.12762
1157.3.98.128/2657.3.98.129 to 57.3.98.19057.3.98.19162
1257.3.98.192/2657.3.98.193 to 57.3.98.25457.3.98.25562
1357.3.99.0/2657.3.99.1 to 57.3.99.6257.3.99.6362
1457.3.99.64/2657.3.99.65 to 57.3.99.12657.3.99.12762
1557.3.99.128/2657.3.99.129 to 57.3.99.19057.3.99.19162
1657.3.99.192/2657.3.99.193 to 57.3.99.25457.3.99.25562
1757.3.100.0/2657.3.100.1 to 57.3.100.6257.3.100.6362
1857.3.100.64/2657.3.100.65 to 57.3.100.12657.3.100.12762
1957.3.100.128/2657.3.100.129 to 57.3.100.19057.3.100.19162
2057.3.100.192/2657.3.100.193 to 57.3.100.25457.3.100.25562
2157.3.101.0/2657.3.101.1 to 57.3.101.6257.3.101.6362
2257.3.101.64/2657.3.101.65 to 57.3.101.12657.3.101.12762
2357.3.101.128/2657.3.101.129 to 57.3.101.19057.3.101.19162
2457.3.101.192/2657.3.101.193 to 57.3.101.25457.3.101.25562
2557.3.102.0/2657.3.102.1 to 57.3.102.6257.3.102.6362
2657.3.102.64/2657.3.102.65 to 57.3.102.12657.3.102.12762
2757.3.102.128/2657.3.102.129 to 57.3.102.19057.3.102.19162
2857.3.102.192/2657.3.102.193 to 57.3.102.25457.3.102.25562
2957.3.103.0/2657.3.103.1 to 57.3.103.6257.3.103.6362
3057.3.103.64/2657.3.103.65 to 57.3.103.12657.3.103.12762
3157.3.103.128/2657.3.103.129 to 57.3.103.19057.3.103.19162
3257.3.103.192/2657.3.103.193 to 57.3.103.25457.3.103.25562
3357.3.104.0/2657.3.104.1 to 57.3.104.6257.3.104.6362
3457.3.104.64/2657.3.104.65 to 57.3.104.12657.3.104.12762
3557.3.104.128/2657.3.104.129 to 57.3.104.19057.3.104.19162
3657.3.104.192/2657.3.104.193 to 57.3.104.25457.3.104.25562
3757.3.105.0/2657.3.105.1 to 57.3.105.6257.3.105.6362
3857.3.105.64/2657.3.105.65 to 57.3.105.12657.3.105.12762
3957.3.105.128/2657.3.105.129 to 57.3.105.19057.3.105.19162
4057.3.105.192/2657.3.105.193 to 57.3.105.25457.3.105.25562
4157.3.106.0/2657.3.106.1 to 57.3.106.6257.3.106.6362
4257.3.106.64/2657.3.106.65 to 57.3.106.12657.3.106.12762
4357.3.106.128/2657.3.106.129 to 57.3.106.19057.3.106.19162
4457.3.106.192/2657.3.106.193 to 57.3.106.25457.3.106.25562
4557.3.107.0/2657.3.107.1 to 57.3.107.6257.3.107.6362
4657.3.107.64/2657.3.107.65 to 57.3.107.12657.3.107.12762
4757.3.107.128/2657.3.107.129 to 57.3.107.19057.3.107.19162
4857.3.107.192/2657.3.107.193 to 57.3.107.25457.3.107.25562
4957.3.108.0/2657.3.108.1 to 57.3.108.6257.3.108.6362
5057.3.108.64/2657.3.108.65 to 57.3.108.12657.3.108.12762
5157.3.108.128/2657.3.108.129 to 57.3.108.19057.3.108.19162
5257.3.108.192/2657.3.108.193 to 57.3.108.25457.3.108.25562
5357.3.109.0/2657.3.109.1 to 57.3.109.6257.3.109.6362
5457.3.109.64/2657.3.109.65 to 57.3.109.12657.3.109.12762
5557.3.109.128/2657.3.109.129 to 57.3.109.19057.3.109.19162
5657.3.109.192/2657.3.109.193 to 57.3.109.25457.3.109.25562
5757.3.110.0/2657.3.110.1 to 57.3.110.6257.3.110.6362
5857.3.110.64/2657.3.110.65 to 57.3.110.12657.3.110.12762
5957.3.110.128/2657.3.110.129 to 57.3.110.19057.3.110.19162
6057.3.110.192/2657.3.110.193 to 57.3.110.25457.3.110.25562
6157.3.111.0/2657.3.111.1 to 57.3.111.6257.3.111.6362
6257.3.111.64/2657.3.111.65 to 57.3.111.12657.3.111.12762
6357.3.111.128/2657.3.111.129 to 57.3.111.19057.3.111.19162
6457.3.111.192/2657.3.111.193 to 57.3.111.25457.3.111.25562
6557.3.112.0/2657.3.112.1 to 57.3.112.6257.3.112.6362
6657.3.112.64/2657.3.112.65 to 57.3.112.12657.3.112.12762
6757.3.112.128/2657.3.112.129 to 57.3.112.19057.3.112.19162
6857.3.112.192/2657.3.112.193 to 57.3.112.25457.3.112.25562
6957.3.113.0/2657.3.113.1 to 57.3.113.6257.3.113.6362
7057.3.113.64/2657.3.113.65 to 57.3.113.12657.3.113.12762
7157.3.113.128/2657.3.113.129 to 57.3.113.19057.3.113.19162
7257.3.113.192/2657.3.113.193 to 57.3.113.25457.3.113.25562
7357.3.114.0/2657.3.114.1 to 57.3.114.6257.3.114.6362
7457.3.114.64/2657.3.114.65 to 57.3.114.12657.3.114.12762
7557.3.114.128/2657.3.114.129 to 57.3.114.19057.3.114.19162
7657.3.114.192/2657.3.114.193 to 57.3.114.25457.3.114.25562
7757.3.115.0/2657.3.115.1 to 57.3.115.6257.3.115.6362
7857.3.115.64/2657.3.115.65 to 57.3.115.12657.3.115.12762
7957.3.115.128/2657.3.115.129 to 57.3.115.19057.3.115.19162
8057.3.115.192/2657.3.115.193 to 57.3.115.25457.3.115.25562
8157.3.116.0/2657.3.116.1 to 57.3.116.6257.3.116.6362
8257.3.116.64/2657.3.116.65 to 57.3.116.12657.3.116.12762
8357.3.116.128/2657.3.116.129 to 57.3.116.19057.3.116.19162
8457.3.116.192/2657.3.116.193 to 57.3.116.25457.3.116.25562
8557.3.117.0/2657.3.117.1 to 57.3.117.6257.3.117.6362
8657.3.117.64/2657.3.117.65 to 57.3.117.12657.3.117.12762
8757.3.117.128/2657.3.117.129 to 57.3.117.19057.3.117.19162
8857.3.117.192/2657.3.117.193 to 57.3.117.25457.3.117.25562
8957.3.118.0/2657.3.118.1 to 57.3.118.6257.3.118.6362
9057.3.118.64/2657.3.118.65 to 57.3.118.12657.3.118.12762
9157.3.118.128/2657.3.118.129 to 57.3.118.19057.3.118.19162
9257.3.118.192/2657.3.118.193 to 57.3.118.25457.3.118.25562
9357.3.119.0/2657.3.119.1 to 57.3.119.6257.3.119.6362
9457.3.119.64/2657.3.119.65 to 57.3.119.12657.3.119.12762
9557.3.119.128/2657.3.119.129 to 57.3.119.19057.3.119.19162
9657.3.119.192/2657.3.119.193 to 57.3.119.25457.3.119.25562
9757.3.120.0/2657.3.120.1 to 57.3.120.6257.3.120.6362
9857.3.120.64/2657.3.120.65 to 57.3.120.12657.3.120.12762
9957.3.120.128/2657.3.120.129 to 57.3.120.19057.3.120.19162
10057.3.120.192/2657.3.120.193 to 57.3.120.25457.3.120.25562
10157.3.121.0/2657.3.121.1 to 57.3.121.6257.3.121.6362
10257.3.121.64/2657.3.121.65 to 57.3.121.12657.3.121.12762
10357.3.121.128/2657.3.121.129 to 57.3.121.19057.3.121.19162
10457.3.121.192/2657.3.121.193 to 57.3.121.25457.3.121.25562
10557.3.122.0/2657.3.122.1 to 57.3.122.6257.3.122.6362
10657.3.122.64/2657.3.122.65 to 57.3.122.12657.3.122.12762
10757.3.122.128/2657.3.122.129 to 57.3.122.19057.3.122.19162
10857.3.122.192/2657.3.122.193 to 57.3.122.25457.3.122.25562
10957.3.123.0/2657.3.123.1 to 57.3.123.6257.3.123.6362
11057.3.123.64/2657.3.123.65 to 57.3.123.12657.3.123.12762
11157.3.123.128/2657.3.123.129 to 57.3.123.19057.3.123.19162
11257.3.123.192/2657.3.123.193 to 57.3.123.25457.3.123.25562
11357.3.124.0/2657.3.124.1 to 57.3.124.6257.3.124.6362
11457.3.124.64/2657.3.124.65 to 57.3.124.12657.3.124.12762
11557.3.124.128/2657.3.124.129 to 57.3.124.19057.3.124.19162
11657.3.124.192/2657.3.124.193 to 57.3.124.25457.3.124.25562
11757.3.125.0/2657.3.125.1 to 57.3.125.6257.3.125.6362
11857.3.125.64/2657.3.125.65 to 57.3.125.12657.3.125.12762
11957.3.125.128/2657.3.125.129 to 57.3.125.19057.3.125.19162
12057.3.125.192/2657.3.125.193 to 57.3.125.25457.3.125.25562
12157.3.126.0/2657.3.126.1 to 57.3.126.6257.3.126.6362
12257.3.126.64/2657.3.126.65 to 57.3.126.12657.3.126.12762
12357.3.126.128/2657.3.126.129 to 57.3.126.19057.3.126.19162
12457.3.126.192/2657.3.126.193 to 57.3.126.25457.3.126.25562
12557.3.127.0/2657.3.127.1 to 57.3.127.6257.3.127.6362
12657.3.127.64/2657.3.127.65 to 57.3.127.12657.3.127.12762
12757.3.127.128/2657.3.127.129 to 57.3.127.19057.3.127.19162
12857.3.127.192/2657.3.127.193 to 57.3.127.25457.3.127.25562

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