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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.

Network93.60.0.0/18
Usable hosts16,382
Subnet mask255.255.192.0
Addresses16,384
Network address
93.60.0.0
Broadcast address
93.60.63.255
First usable
93.60.0.1
Last usable
93.60.63.254
Usable hosts
16,382 (16,384 less the network and broadcast addresses)
Subnet mask
255.255.192.0
Wildcard mask
0.0.63.255 (Cisco ACLs, OSPF)
Prefix length
/18
Type
Public public
Old class
A (default /8)
As numbers
Hex 5D3C0000 · Integer 1564213248 to 1564229631
Reverse DNS zones
0.60.93.in-addr.arpa
1.60.93.in-addr.arpa
2.60.93.in-addr.arpa
3.60.93.in-addr.arpa
4.60.93.in-addr.arpa
5.60.93.in-addr.arpa
6.60.93.in-addr.arpa
7.60.93.in-addr.arpa
8.60.93.in-addr.arpa
9.60.93.in-addr.arpa
10.60.93.in-addr.arpa
11.60.93.in-addr.arpa
12.60.93.in-addr.arpa
13.60.93.in-addr.arpa
14.60.93.in-addr.arpa
15.60.93.in-addr.arpa
and 48 more
/18 is not on a 8-bit boundary, so it takes 64 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011101.00111100.00000000.0000000093.60.0.0
Subnet mask11111111.11111111.11000000.00000000255.255.192.0
Network01011101.00111100.00000000.0000000093.60.0.0
Broadcast01011101.00111100.00111111.1111111193.60.63.255
Split into smaller subnets/25
/19 (2)/20 (4)/21 (8)/22 (16)/23 (32)/24 (64)/25 (128)/26 (256)/27 (512)/28 (1,024)/29 (2,048)/30 (4,096)

93.60.0.0/18 makes 128 subnets of /25.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
193.60.0.0/2593.60.0.1 to 93.60.0.12693.60.0.127126
293.60.0.128/2593.60.0.129 to 93.60.0.25493.60.0.255126
393.60.1.0/2593.60.1.1 to 93.60.1.12693.60.1.127126
493.60.1.128/2593.60.1.129 to 93.60.1.25493.60.1.255126
593.60.2.0/2593.60.2.1 to 93.60.2.12693.60.2.127126
693.60.2.128/2593.60.2.129 to 93.60.2.25493.60.2.255126
793.60.3.0/2593.60.3.1 to 93.60.3.12693.60.3.127126
893.60.3.128/2593.60.3.129 to 93.60.3.25493.60.3.255126
993.60.4.0/2593.60.4.1 to 93.60.4.12693.60.4.127126
1093.60.4.128/2593.60.4.129 to 93.60.4.25493.60.4.255126
1193.60.5.0/2593.60.5.1 to 93.60.5.12693.60.5.127126
1293.60.5.128/2593.60.5.129 to 93.60.5.25493.60.5.255126
1393.60.6.0/2593.60.6.1 to 93.60.6.12693.60.6.127126
1493.60.6.128/2593.60.6.129 to 93.60.6.25493.60.6.255126
1593.60.7.0/2593.60.7.1 to 93.60.7.12693.60.7.127126
1693.60.7.128/2593.60.7.129 to 93.60.7.25493.60.7.255126
1793.60.8.0/2593.60.8.1 to 93.60.8.12693.60.8.127126
1893.60.8.128/2593.60.8.129 to 93.60.8.25493.60.8.255126
1993.60.9.0/2593.60.9.1 to 93.60.9.12693.60.9.127126
2093.60.9.128/2593.60.9.129 to 93.60.9.25493.60.9.255126
2193.60.10.0/2593.60.10.1 to 93.60.10.12693.60.10.127126
2293.60.10.128/2593.60.10.129 to 93.60.10.25493.60.10.255126
2393.60.11.0/2593.60.11.1 to 93.60.11.12693.60.11.127126
2493.60.11.128/2593.60.11.129 to 93.60.11.25493.60.11.255126
2593.60.12.0/2593.60.12.1 to 93.60.12.12693.60.12.127126
2693.60.12.128/2593.60.12.129 to 93.60.12.25493.60.12.255126
2793.60.13.0/2593.60.13.1 to 93.60.13.12693.60.13.127126
2893.60.13.128/2593.60.13.129 to 93.60.13.25493.60.13.255126
2993.60.14.0/2593.60.14.1 to 93.60.14.12693.60.14.127126
3093.60.14.128/2593.60.14.129 to 93.60.14.25493.60.14.255126
3193.60.15.0/2593.60.15.1 to 93.60.15.12693.60.15.127126
3293.60.15.128/2593.60.15.129 to 93.60.15.25493.60.15.255126
3393.60.16.0/2593.60.16.1 to 93.60.16.12693.60.16.127126
3493.60.16.128/2593.60.16.129 to 93.60.16.25493.60.16.255126
3593.60.17.0/2593.60.17.1 to 93.60.17.12693.60.17.127126
3693.60.17.128/2593.60.17.129 to 93.60.17.25493.60.17.255126
3793.60.18.0/2593.60.18.1 to 93.60.18.12693.60.18.127126
3893.60.18.128/2593.60.18.129 to 93.60.18.25493.60.18.255126
3993.60.19.0/2593.60.19.1 to 93.60.19.12693.60.19.127126
4093.60.19.128/2593.60.19.129 to 93.60.19.25493.60.19.255126
4193.60.20.0/2593.60.20.1 to 93.60.20.12693.60.20.127126
4293.60.20.128/2593.60.20.129 to 93.60.20.25493.60.20.255126
4393.60.21.0/2593.60.21.1 to 93.60.21.12693.60.21.127126
4493.60.21.128/2593.60.21.129 to 93.60.21.25493.60.21.255126
4593.60.22.0/2593.60.22.1 to 93.60.22.12693.60.22.127126
4693.60.22.128/2593.60.22.129 to 93.60.22.25493.60.22.255126
4793.60.23.0/2593.60.23.1 to 93.60.23.12693.60.23.127126
4893.60.23.128/2593.60.23.129 to 93.60.23.25493.60.23.255126
4993.60.24.0/2593.60.24.1 to 93.60.24.12693.60.24.127126
5093.60.24.128/2593.60.24.129 to 93.60.24.25493.60.24.255126
5193.60.25.0/2593.60.25.1 to 93.60.25.12693.60.25.127126
5293.60.25.128/2593.60.25.129 to 93.60.25.25493.60.25.255126
5393.60.26.0/2593.60.26.1 to 93.60.26.12693.60.26.127126
5493.60.26.128/2593.60.26.129 to 93.60.26.25493.60.26.255126
5593.60.27.0/2593.60.27.1 to 93.60.27.12693.60.27.127126
5693.60.27.128/2593.60.27.129 to 93.60.27.25493.60.27.255126
5793.60.28.0/2593.60.28.1 to 93.60.28.12693.60.28.127126
5893.60.28.128/2593.60.28.129 to 93.60.28.25493.60.28.255126
5993.60.29.0/2593.60.29.1 to 93.60.29.12693.60.29.127126
6093.60.29.128/2593.60.29.129 to 93.60.29.25493.60.29.255126
6193.60.30.0/2593.60.30.1 to 93.60.30.12693.60.30.127126
6293.60.30.128/2593.60.30.129 to 93.60.30.25493.60.30.255126
6393.60.31.0/2593.60.31.1 to 93.60.31.12693.60.31.127126
6493.60.31.128/2593.60.31.129 to 93.60.31.25493.60.31.255126
6593.60.32.0/2593.60.32.1 to 93.60.32.12693.60.32.127126
6693.60.32.128/2593.60.32.129 to 93.60.32.25493.60.32.255126
6793.60.33.0/2593.60.33.1 to 93.60.33.12693.60.33.127126
6893.60.33.128/2593.60.33.129 to 93.60.33.25493.60.33.255126
6993.60.34.0/2593.60.34.1 to 93.60.34.12693.60.34.127126
7093.60.34.128/2593.60.34.129 to 93.60.34.25493.60.34.255126
7193.60.35.0/2593.60.35.1 to 93.60.35.12693.60.35.127126
7293.60.35.128/2593.60.35.129 to 93.60.35.25493.60.35.255126
7393.60.36.0/2593.60.36.1 to 93.60.36.12693.60.36.127126
7493.60.36.128/2593.60.36.129 to 93.60.36.25493.60.36.255126
7593.60.37.0/2593.60.37.1 to 93.60.37.12693.60.37.127126
7693.60.37.128/2593.60.37.129 to 93.60.37.25493.60.37.255126
7793.60.38.0/2593.60.38.1 to 93.60.38.12693.60.38.127126
7893.60.38.128/2593.60.38.129 to 93.60.38.25493.60.38.255126
7993.60.39.0/2593.60.39.1 to 93.60.39.12693.60.39.127126
8093.60.39.128/2593.60.39.129 to 93.60.39.25493.60.39.255126
8193.60.40.0/2593.60.40.1 to 93.60.40.12693.60.40.127126
8293.60.40.128/2593.60.40.129 to 93.60.40.25493.60.40.255126
8393.60.41.0/2593.60.41.1 to 93.60.41.12693.60.41.127126
8493.60.41.128/2593.60.41.129 to 93.60.41.25493.60.41.255126
8593.60.42.0/2593.60.42.1 to 93.60.42.12693.60.42.127126
8693.60.42.128/2593.60.42.129 to 93.60.42.25493.60.42.255126
8793.60.43.0/2593.60.43.1 to 93.60.43.12693.60.43.127126
8893.60.43.128/2593.60.43.129 to 93.60.43.25493.60.43.255126
8993.60.44.0/2593.60.44.1 to 93.60.44.12693.60.44.127126
9093.60.44.128/2593.60.44.129 to 93.60.44.25493.60.44.255126
9193.60.45.0/2593.60.45.1 to 93.60.45.12693.60.45.127126
9293.60.45.128/2593.60.45.129 to 93.60.45.25493.60.45.255126
9393.60.46.0/2593.60.46.1 to 93.60.46.12693.60.46.127126
9493.60.46.128/2593.60.46.129 to 93.60.46.25493.60.46.255126
9593.60.47.0/2593.60.47.1 to 93.60.47.12693.60.47.127126
9693.60.47.128/2593.60.47.129 to 93.60.47.25493.60.47.255126
9793.60.48.0/2593.60.48.1 to 93.60.48.12693.60.48.127126
9893.60.48.128/2593.60.48.129 to 93.60.48.25493.60.48.255126
9993.60.49.0/2593.60.49.1 to 93.60.49.12693.60.49.127126
10093.60.49.128/2593.60.49.129 to 93.60.49.25493.60.49.255126
10193.60.50.0/2593.60.50.1 to 93.60.50.12693.60.50.127126
10293.60.50.128/2593.60.50.129 to 93.60.50.25493.60.50.255126
10393.60.51.0/2593.60.51.1 to 93.60.51.12693.60.51.127126
10493.60.51.128/2593.60.51.129 to 93.60.51.25493.60.51.255126
10593.60.52.0/2593.60.52.1 to 93.60.52.12693.60.52.127126
10693.60.52.128/2593.60.52.129 to 93.60.52.25493.60.52.255126
10793.60.53.0/2593.60.53.1 to 93.60.53.12693.60.53.127126
10893.60.53.128/2593.60.53.129 to 93.60.53.25493.60.53.255126
10993.60.54.0/2593.60.54.1 to 93.60.54.12693.60.54.127126
11093.60.54.128/2593.60.54.129 to 93.60.54.25493.60.54.255126
11193.60.55.0/2593.60.55.1 to 93.60.55.12693.60.55.127126
11293.60.55.128/2593.60.55.129 to 93.60.55.25493.60.55.255126
11393.60.56.0/2593.60.56.1 to 93.60.56.12693.60.56.127126
11493.60.56.128/2593.60.56.129 to 93.60.56.25493.60.56.255126
11593.60.57.0/2593.60.57.1 to 93.60.57.12693.60.57.127126
11693.60.57.128/2593.60.57.129 to 93.60.57.25493.60.57.255126
11793.60.58.0/2593.60.58.1 to 93.60.58.12693.60.58.127126
11893.60.58.128/2593.60.58.129 to 93.60.58.25493.60.58.255126
11993.60.59.0/2593.60.59.1 to 93.60.59.12693.60.59.127126
12093.60.59.128/2593.60.59.129 to 93.60.59.25493.60.59.255126
12193.60.60.0/2593.60.60.1 to 93.60.60.12693.60.60.127126
12293.60.60.128/2593.60.60.129 to 93.60.60.25493.60.60.255126
12393.60.61.0/2593.60.61.1 to 93.60.61.12693.60.61.127126
12493.60.61.128/2593.60.61.129 to 93.60.61.25493.60.61.255126
12593.60.62.0/2593.60.62.1 to 93.60.62.12693.60.62.127126
12693.60.62.128/2593.60.62.129 to 93.60.62.25493.60.62.255126
12793.60.63.0/2593.60.63.1 to 93.60.63.12693.60.63.127126
12893.60.63.128/2593.60.63.129 to 93.60.63.25493.60.63.255126

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.