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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.

Network53.30.0.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
53.30.0.0
Broadcast address
53.30.31.255
First usable
53.30.0.1
Last usable
53.30.31.254
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 351E0000 · Integer 891158528 to 891166719
Reverse DNS zones
0.30.53.in-addr.arpa
1.30.53.in-addr.arpa
2.30.53.in-addr.arpa
3.30.53.in-addr.arpa
4.30.53.in-addr.arpa
5.30.53.in-addr.arpa
6.30.53.in-addr.arpa
7.30.53.in-addr.arpa
8.30.53.in-addr.arpa
9.30.53.in-addr.arpa
10.30.53.in-addr.arpa
11.30.53.in-addr.arpa
12.30.53.in-addr.arpa
13.30.53.in-addr.arpa
14.30.53.in-addr.arpa
15.30.53.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
Address00110101.00011110.00000000.0000000053.30.0.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network00110101.00011110.00000000.0000000053.30.0.0
Broadcast00110101.00011110.00011111.1111111153.30.31.255
Split into smaller subnets/26

53.30.0.0/19 makes 128 subnets of /26.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
153.30.0.0/2653.30.0.1 to 53.30.0.6253.30.0.6362
253.30.0.64/2653.30.0.65 to 53.30.0.12653.30.0.12762
353.30.0.128/2653.30.0.129 to 53.30.0.19053.30.0.19162
453.30.0.192/2653.30.0.193 to 53.30.0.25453.30.0.25562
553.30.1.0/2653.30.1.1 to 53.30.1.6253.30.1.6362
653.30.1.64/2653.30.1.65 to 53.30.1.12653.30.1.12762
753.30.1.128/2653.30.1.129 to 53.30.1.19053.30.1.19162
853.30.1.192/2653.30.1.193 to 53.30.1.25453.30.1.25562
953.30.2.0/2653.30.2.1 to 53.30.2.6253.30.2.6362
1053.30.2.64/2653.30.2.65 to 53.30.2.12653.30.2.12762
1153.30.2.128/2653.30.2.129 to 53.30.2.19053.30.2.19162
1253.30.2.192/2653.30.2.193 to 53.30.2.25453.30.2.25562
1353.30.3.0/2653.30.3.1 to 53.30.3.6253.30.3.6362
1453.30.3.64/2653.30.3.65 to 53.30.3.12653.30.3.12762
1553.30.3.128/2653.30.3.129 to 53.30.3.19053.30.3.19162
1653.30.3.192/2653.30.3.193 to 53.30.3.25453.30.3.25562
1753.30.4.0/2653.30.4.1 to 53.30.4.6253.30.4.6362
1853.30.4.64/2653.30.4.65 to 53.30.4.12653.30.4.12762
1953.30.4.128/2653.30.4.129 to 53.30.4.19053.30.4.19162
2053.30.4.192/2653.30.4.193 to 53.30.4.25453.30.4.25562
2153.30.5.0/2653.30.5.1 to 53.30.5.6253.30.5.6362
2253.30.5.64/2653.30.5.65 to 53.30.5.12653.30.5.12762
2353.30.5.128/2653.30.5.129 to 53.30.5.19053.30.5.19162
2453.30.5.192/2653.30.5.193 to 53.30.5.25453.30.5.25562
2553.30.6.0/2653.30.6.1 to 53.30.6.6253.30.6.6362
2653.30.6.64/2653.30.6.65 to 53.30.6.12653.30.6.12762
2753.30.6.128/2653.30.6.129 to 53.30.6.19053.30.6.19162
2853.30.6.192/2653.30.6.193 to 53.30.6.25453.30.6.25562
2953.30.7.0/2653.30.7.1 to 53.30.7.6253.30.7.6362
3053.30.7.64/2653.30.7.65 to 53.30.7.12653.30.7.12762
3153.30.7.128/2653.30.7.129 to 53.30.7.19053.30.7.19162
3253.30.7.192/2653.30.7.193 to 53.30.7.25453.30.7.25562
3353.30.8.0/2653.30.8.1 to 53.30.8.6253.30.8.6362
3453.30.8.64/2653.30.8.65 to 53.30.8.12653.30.8.12762
3553.30.8.128/2653.30.8.129 to 53.30.8.19053.30.8.19162
3653.30.8.192/2653.30.8.193 to 53.30.8.25453.30.8.25562
3753.30.9.0/2653.30.9.1 to 53.30.9.6253.30.9.6362
3853.30.9.64/2653.30.9.65 to 53.30.9.12653.30.9.12762
3953.30.9.128/2653.30.9.129 to 53.30.9.19053.30.9.19162
4053.30.9.192/2653.30.9.193 to 53.30.9.25453.30.9.25562
4153.30.10.0/2653.30.10.1 to 53.30.10.6253.30.10.6362
4253.30.10.64/2653.30.10.65 to 53.30.10.12653.30.10.12762
4353.30.10.128/2653.30.10.129 to 53.30.10.19053.30.10.19162
4453.30.10.192/2653.30.10.193 to 53.30.10.25453.30.10.25562
4553.30.11.0/2653.30.11.1 to 53.30.11.6253.30.11.6362
4653.30.11.64/2653.30.11.65 to 53.30.11.12653.30.11.12762
4753.30.11.128/2653.30.11.129 to 53.30.11.19053.30.11.19162
4853.30.11.192/2653.30.11.193 to 53.30.11.25453.30.11.25562
4953.30.12.0/2653.30.12.1 to 53.30.12.6253.30.12.6362
5053.30.12.64/2653.30.12.65 to 53.30.12.12653.30.12.12762
5153.30.12.128/2653.30.12.129 to 53.30.12.19053.30.12.19162
5253.30.12.192/2653.30.12.193 to 53.30.12.25453.30.12.25562
5353.30.13.0/2653.30.13.1 to 53.30.13.6253.30.13.6362
5453.30.13.64/2653.30.13.65 to 53.30.13.12653.30.13.12762
5553.30.13.128/2653.30.13.129 to 53.30.13.19053.30.13.19162
5653.30.13.192/2653.30.13.193 to 53.30.13.25453.30.13.25562
5753.30.14.0/2653.30.14.1 to 53.30.14.6253.30.14.6362
5853.30.14.64/2653.30.14.65 to 53.30.14.12653.30.14.12762
5953.30.14.128/2653.30.14.129 to 53.30.14.19053.30.14.19162
6053.30.14.192/2653.30.14.193 to 53.30.14.25453.30.14.25562
6153.30.15.0/2653.30.15.1 to 53.30.15.6253.30.15.6362
6253.30.15.64/2653.30.15.65 to 53.30.15.12653.30.15.12762
6353.30.15.128/2653.30.15.129 to 53.30.15.19053.30.15.19162
6453.30.15.192/2653.30.15.193 to 53.30.15.25453.30.15.25562
6553.30.16.0/2653.30.16.1 to 53.30.16.6253.30.16.6362
6653.30.16.64/2653.30.16.65 to 53.30.16.12653.30.16.12762
6753.30.16.128/2653.30.16.129 to 53.30.16.19053.30.16.19162
6853.30.16.192/2653.30.16.193 to 53.30.16.25453.30.16.25562
6953.30.17.0/2653.30.17.1 to 53.30.17.6253.30.17.6362
7053.30.17.64/2653.30.17.65 to 53.30.17.12653.30.17.12762
7153.30.17.128/2653.30.17.129 to 53.30.17.19053.30.17.19162
7253.30.17.192/2653.30.17.193 to 53.30.17.25453.30.17.25562
7353.30.18.0/2653.30.18.1 to 53.30.18.6253.30.18.6362
7453.30.18.64/2653.30.18.65 to 53.30.18.12653.30.18.12762
7553.30.18.128/2653.30.18.129 to 53.30.18.19053.30.18.19162
7653.30.18.192/2653.30.18.193 to 53.30.18.25453.30.18.25562
7753.30.19.0/2653.30.19.1 to 53.30.19.6253.30.19.6362
7853.30.19.64/2653.30.19.65 to 53.30.19.12653.30.19.12762
7953.30.19.128/2653.30.19.129 to 53.30.19.19053.30.19.19162
8053.30.19.192/2653.30.19.193 to 53.30.19.25453.30.19.25562
8153.30.20.0/2653.30.20.1 to 53.30.20.6253.30.20.6362
8253.30.20.64/2653.30.20.65 to 53.30.20.12653.30.20.12762
8353.30.20.128/2653.30.20.129 to 53.30.20.19053.30.20.19162
8453.30.20.192/2653.30.20.193 to 53.30.20.25453.30.20.25562
8553.30.21.0/2653.30.21.1 to 53.30.21.6253.30.21.6362
8653.30.21.64/2653.30.21.65 to 53.30.21.12653.30.21.12762
8753.30.21.128/2653.30.21.129 to 53.30.21.19053.30.21.19162
8853.30.21.192/2653.30.21.193 to 53.30.21.25453.30.21.25562
8953.30.22.0/2653.30.22.1 to 53.30.22.6253.30.22.6362
9053.30.22.64/2653.30.22.65 to 53.30.22.12653.30.22.12762
9153.30.22.128/2653.30.22.129 to 53.30.22.19053.30.22.19162
9253.30.22.192/2653.30.22.193 to 53.30.22.25453.30.22.25562
9353.30.23.0/2653.30.23.1 to 53.30.23.6253.30.23.6362
9453.30.23.64/2653.30.23.65 to 53.30.23.12653.30.23.12762
9553.30.23.128/2653.30.23.129 to 53.30.23.19053.30.23.19162
9653.30.23.192/2653.30.23.193 to 53.30.23.25453.30.23.25562
9753.30.24.0/2653.30.24.1 to 53.30.24.6253.30.24.6362
9853.30.24.64/2653.30.24.65 to 53.30.24.12653.30.24.12762
9953.30.24.128/2653.30.24.129 to 53.30.24.19053.30.24.19162
10053.30.24.192/2653.30.24.193 to 53.30.24.25453.30.24.25562
10153.30.25.0/2653.30.25.1 to 53.30.25.6253.30.25.6362
10253.30.25.64/2653.30.25.65 to 53.30.25.12653.30.25.12762
10353.30.25.128/2653.30.25.129 to 53.30.25.19053.30.25.19162
10453.30.25.192/2653.30.25.193 to 53.30.25.25453.30.25.25562
10553.30.26.0/2653.30.26.1 to 53.30.26.6253.30.26.6362
10653.30.26.64/2653.30.26.65 to 53.30.26.12653.30.26.12762
10753.30.26.128/2653.30.26.129 to 53.30.26.19053.30.26.19162
10853.30.26.192/2653.30.26.193 to 53.30.26.25453.30.26.25562
10953.30.27.0/2653.30.27.1 to 53.30.27.6253.30.27.6362
11053.30.27.64/2653.30.27.65 to 53.30.27.12653.30.27.12762
11153.30.27.128/2653.30.27.129 to 53.30.27.19053.30.27.19162
11253.30.27.192/2653.30.27.193 to 53.30.27.25453.30.27.25562
11353.30.28.0/2653.30.28.1 to 53.30.28.6253.30.28.6362
11453.30.28.64/2653.30.28.65 to 53.30.28.12653.30.28.12762
11553.30.28.128/2653.30.28.129 to 53.30.28.19053.30.28.19162
11653.30.28.192/2653.30.28.193 to 53.30.28.25453.30.28.25562
11753.30.29.0/2653.30.29.1 to 53.30.29.6253.30.29.6362
11853.30.29.64/2653.30.29.65 to 53.30.29.12653.30.29.12762
11953.30.29.128/2653.30.29.129 to 53.30.29.19053.30.29.19162
12053.30.29.192/2653.30.29.193 to 53.30.29.25453.30.29.25562
12153.30.30.0/2653.30.30.1 to 53.30.30.6253.30.30.6362
12253.30.30.64/2653.30.30.65 to 53.30.30.12653.30.30.12762
12353.30.30.128/2653.30.30.129 to 53.30.30.19053.30.30.19162
12453.30.30.192/2653.30.30.193 to 53.30.30.25453.30.30.25562
12553.30.31.0/2653.30.31.1 to 53.30.31.6253.30.31.6362
12653.30.31.64/2653.30.31.65 to 53.30.31.12653.30.31.12762
12753.30.31.128/2653.30.31.129 to 53.30.31.19053.30.31.19162
12853.30.31.192/2653.30.31.193 to 53.30.31.25453.30.31.25562

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