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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.

Network60.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
60.0.0.0
Broadcast address
60.255.255.255
First usable
60.0.0.1
Last usable
60.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 3C000000 · Integer 1006632960 to 1023410175
Reverse DNS zone
60.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00111100..00000000.00000000.0000000060.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network00111100..00000000.00000000.0000000060.0.0.0
Broadcast00111100..11111111.11111111.1111111160.255.255.255
Split into smaller subnets/15
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

60.0.0.0/8 makes 128 subnets of /15.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
160.0.0.0/1560.0.0.1 to 60.1.255.25460.1.255.255131,070
260.2.0.0/1560.2.0.1 to 60.3.255.25460.3.255.255131,070
360.4.0.0/1560.4.0.1 to 60.5.255.25460.5.255.255131,070
460.6.0.0/1560.6.0.1 to 60.7.255.25460.7.255.255131,070
560.8.0.0/1560.8.0.1 to 60.9.255.25460.9.255.255131,070
660.10.0.0/1560.10.0.1 to 60.11.255.25460.11.255.255131,070
760.12.0.0/1560.12.0.1 to 60.13.255.25460.13.255.255131,070
860.14.0.0/1560.14.0.1 to 60.15.255.25460.15.255.255131,070
960.16.0.0/1560.16.0.1 to 60.17.255.25460.17.255.255131,070
1060.18.0.0/1560.18.0.1 to 60.19.255.25460.19.255.255131,070
1160.20.0.0/1560.20.0.1 to 60.21.255.25460.21.255.255131,070
1260.22.0.0/1560.22.0.1 to 60.23.255.25460.23.255.255131,070
1360.24.0.0/1560.24.0.1 to 60.25.255.25460.25.255.255131,070
1460.26.0.0/1560.26.0.1 to 60.27.255.25460.27.255.255131,070
1560.28.0.0/1560.28.0.1 to 60.29.255.25460.29.255.255131,070
1660.30.0.0/1560.30.0.1 to 60.31.255.25460.31.255.255131,070
1760.32.0.0/1560.32.0.1 to 60.33.255.25460.33.255.255131,070
1860.34.0.0/1560.34.0.1 to 60.35.255.25460.35.255.255131,070
1960.36.0.0/1560.36.0.1 to 60.37.255.25460.37.255.255131,070
2060.38.0.0/1560.38.0.1 to 60.39.255.25460.39.255.255131,070
2160.40.0.0/1560.40.0.1 to 60.41.255.25460.41.255.255131,070
2260.42.0.0/1560.42.0.1 to 60.43.255.25460.43.255.255131,070
2360.44.0.0/1560.44.0.1 to 60.45.255.25460.45.255.255131,070
2460.46.0.0/1560.46.0.1 to 60.47.255.25460.47.255.255131,070
2560.48.0.0/1560.48.0.1 to 60.49.255.25460.49.255.255131,070
2660.50.0.0/1560.50.0.1 to 60.51.255.25460.51.255.255131,070
2760.52.0.0/1560.52.0.1 to 60.53.255.25460.53.255.255131,070
2860.54.0.0/1560.54.0.1 to 60.55.255.25460.55.255.255131,070
2960.56.0.0/1560.56.0.1 to 60.57.255.25460.57.255.255131,070
3060.58.0.0/1560.58.0.1 to 60.59.255.25460.59.255.255131,070
3160.60.0.0/1560.60.0.1 to 60.61.255.25460.61.255.255131,070
3260.62.0.0/1560.62.0.1 to 60.63.255.25460.63.255.255131,070
3360.64.0.0/1560.64.0.1 to 60.65.255.25460.65.255.255131,070
3460.66.0.0/1560.66.0.1 to 60.67.255.25460.67.255.255131,070
3560.68.0.0/1560.68.0.1 to 60.69.255.25460.69.255.255131,070
3660.70.0.0/1560.70.0.1 to 60.71.255.25460.71.255.255131,070
3760.72.0.0/1560.72.0.1 to 60.73.255.25460.73.255.255131,070
3860.74.0.0/1560.74.0.1 to 60.75.255.25460.75.255.255131,070
3960.76.0.0/1560.76.0.1 to 60.77.255.25460.77.255.255131,070
4060.78.0.0/1560.78.0.1 to 60.79.255.25460.79.255.255131,070
4160.80.0.0/1560.80.0.1 to 60.81.255.25460.81.255.255131,070
4260.82.0.0/1560.82.0.1 to 60.83.255.25460.83.255.255131,070
4360.84.0.0/1560.84.0.1 to 60.85.255.25460.85.255.255131,070
4460.86.0.0/1560.86.0.1 to 60.87.255.25460.87.255.255131,070
4560.88.0.0/1560.88.0.1 to 60.89.255.25460.89.255.255131,070
4660.90.0.0/1560.90.0.1 to 60.91.255.25460.91.255.255131,070
4760.92.0.0/1560.92.0.1 to 60.93.255.25460.93.255.255131,070
4860.94.0.0/1560.94.0.1 to 60.95.255.25460.95.255.255131,070
4960.96.0.0/1560.96.0.1 to 60.97.255.25460.97.255.255131,070
5060.98.0.0/1560.98.0.1 to 60.99.255.25460.99.255.255131,070
5160.100.0.0/1560.100.0.1 to 60.101.255.25460.101.255.255131,070
5260.102.0.0/1560.102.0.1 to 60.103.255.25460.103.255.255131,070
5360.104.0.0/1560.104.0.1 to 60.105.255.25460.105.255.255131,070
5460.106.0.0/1560.106.0.1 to 60.107.255.25460.107.255.255131,070
5560.108.0.0/1560.108.0.1 to 60.109.255.25460.109.255.255131,070
5660.110.0.0/1560.110.0.1 to 60.111.255.25460.111.255.255131,070
5760.112.0.0/1560.112.0.1 to 60.113.255.25460.113.255.255131,070
5860.114.0.0/1560.114.0.1 to 60.115.255.25460.115.255.255131,070
5960.116.0.0/1560.116.0.1 to 60.117.255.25460.117.255.255131,070
6060.118.0.0/1560.118.0.1 to 60.119.255.25460.119.255.255131,070
6160.120.0.0/1560.120.0.1 to 60.121.255.25460.121.255.255131,070
6260.122.0.0/1560.122.0.1 to 60.123.255.25460.123.255.255131,070
6360.124.0.0/1560.124.0.1 to 60.125.255.25460.125.255.255131,070
6460.126.0.0/1560.126.0.1 to 60.127.255.25460.127.255.255131,070
6560.128.0.0/1560.128.0.1 to 60.129.255.25460.129.255.255131,070
6660.130.0.0/1560.130.0.1 to 60.131.255.25460.131.255.255131,070
6760.132.0.0/1560.132.0.1 to 60.133.255.25460.133.255.255131,070
6860.134.0.0/1560.134.0.1 to 60.135.255.25460.135.255.255131,070
6960.136.0.0/1560.136.0.1 to 60.137.255.25460.137.255.255131,070
7060.138.0.0/1560.138.0.1 to 60.139.255.25460.139.255.255131,070
7160.140.0.0/1560.140.0.1 to 60.141.255.25460.141.255.255131,070
7260.142.0.0/1560.142.0.1 to 60.143.255.25460.143.255.255131,070
7360.144.0.0/1560.144.0.1 to 60.145.255.25460.145.255.255131,070
7460.146.0.0/1560.146.0.1 to 60.147.255.25460.147.255.255131,070
7560.148.0.0/1560.148.0.1 to 60.149.255.25460.149.255.255131,070
7660.150.0.0/1560.150.0.1 to 60.151.255.25460.151.255.255131,070
7760.152.0.0/1560.152.0.1 to 60.153.255.25460.153.255.255131,070
7860.154.0.0/1560.154.0.1 to 60.155.255.25460.155.255.255131,070
7960.156.0.0/1560.156.0.1 to 60.157.255.25460.157.255.255131,070
8060.158.0.0/1560.158.0.1 to 60.159.255.25460.159.255.255131,070
8160.160.0.0/1560.160.0.1 to 60.161.255.25460.161.255.255131,070
8260.162.0.0/1560.162.0.1 to 60.163.255.25460.163.255.255131,070
8360.164.0.0/1560.164.0.1 to 60.165.255.25460.165.255.255131,070
8460.166.0.0/1560.166.0.1 to 60.167.255.25460.167.255.255131,070
8560.168.0.0/1560.168.0.1 to 60.169.255.25460.169.255.255131,070
8660.170.0.0/1560.170.0.1 to 60.171.255.25460.171.255.255131,070
8760.172.0.0/1560.172.0.1 to 60.173.255.25460.173.255.255131,070
8860.174.0.0/1560.174.0.1 to 60.175.255.25460.175.255.255131,070
8960.176.0.0/1560.176.0.1 to 60.177.255.25460.177.255.255131,070
9060.178.0.0/1560.178.0.1 to 60.179.255.25460.179.255.255131,070
9160.180.0.0/1560.180.0.1 to 60.181.255.25460.181.255.255131,070
9260.182.0.0/1560.182.0.1 to 60.183.255.25460.183.255.255131,070
9360.184.0.0/1560.184.0.1 to 60.185.255.25460.185.255.255131,070
9460.186.0.0/1560.186.0.1 to 60.187.255.25460.187.255.255131,070
9560.188.0.0/1560.188.0.1 to 60.189.255.25460.189.255.255131,070
9660.190.0.0/1560.190.0.1 to 60.191.255.25460.191.255.255131,070
9760.192.0.0/1560.192.0.1 to 60.193.255.25460.193.255.255131,070
9860.194.0.0/1560.194.0.1 to 60.195.255.25460.195.255.255131,070
9960.196.0.0/1560.196.0.1 to 60.197.255.25460.197.255.255131,070
10060.198.0.0/1560.198.0.1 to 60.199.255.25460.199.255.255131,070
10160.200.0.0/1560.200.0.1 to 60.201.255.25460.201.255.255131,070
10260.202.0.0/1560.202.0.1 to 60.203.255.25460.203.255.255131,070
10360.204.0.0/1560.204.0.1 to 60.205.255.25460.205.255.255131,070
10460.206.0.0/1560.206.0.1 to 60.207.255.25460.207.255.255131,070
10560.208.0.0/1560.208.0.1 to 60.209.255.25460.209.255.255131,070
10660.210.0.0/1560.210.0.1 to 60.211.255.25460.211.255.255131,070
10760.212.0.0/1560.212.0.1 to 60.213.255.25460.213.255.255131,070
10860.214.0.0/1560.214.0.1 to 60.215.255.25460.215.255.255131,070
10960.216.0.0/1560.216.0.1 to 60.217.255.25460.217.255.255131,070
11060.218.0.0/1560.218.0.1 to 60.219.255.25460.219.255.255131,070
11160.220.0.0/1560.220.0.1 to 60.221.255.25460.221.255.255131,070
11260.222.0.0/1560.222.0.1 to 60.223.255.25460.223.255.255131,070
11360.224.0.0/1560.224.0.1 to 60.225.255.25460.225.255.255131,070
11460.226.0.0/1560.226.0.1 to 60.227.255.25460.227.255.255131,070
11560.228.0.0/1560.228.0.1 to 60.229.255.25460.229.255.255131,070
11660.230.0.0/1560.230.0.1 to 60.231.255.25460.231.255.255131,070
11760.232.0.0/1560.232.0.1 to 60.233.255.25460.233.255.255131,070
11860.234.0.0/1560.234.0.1 to 60.235.255.25460.235.255.255131,070
11960.236.0.0/1560.236.0.1 to 60.237.255.25460.237.255.255131,070
12060.238.0.0/1560.238.0.1 to 60.239.255.25460.239.255.255131,070
12160.240.0.0/1560.240.0.1 to 60.241.255.25460.241.255.255131,070
12260.242.0.0/1560.242.0.1 to 60.243.255.25460.243.255.255131,070
12360.244.0.0/1560.244.0.1 to 60.245.255.25460.245.255.255131,070
12460.246.0.0/1560.246.0.1 to 60.247.255.25460.247.255.255131,070
12560.248.0.0/1560.248.0.1 to 60.249.255.25460.249.255.255131,070
12660.250.0.0/1560.250.0.1 to 60.251.255.25460.251.255.255131,070
12760.252.0.0/1560.252.0.1 to 60.253.255.25460.253.255.255131,070
12860.254.0.0/1560.254.0.1 to 60.255.255.25460.255.255.255131,070

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.