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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.

Network90.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
90.0.0.0
Broadcast address
91.255.255.255
First usable
90.0.0.1
Last usable
91.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 5A000000 · Integer 1509949440 to 1543503871
Reverse DNS zones
90.in-addr.arpa
91.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01011010.00000000.00000000.0000000090.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network01011010.00000000.00000000.0000000090.0.0.0
Broadcast01011011.11111111.11111111.1111111191.255.255.255
Split into smaller subnets/14

90.0.0.0/7 makes 128 subnets of /14.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
190.0.0.0/1490.0.0.1 to 90.3.255.25490.3.255.255262,142
290.4.0.0/1490.4.0.1 to 90.7.255.25490.7.255.255262,142
390.8.0.0/1490.8.0.1 to 90.11.255.25490.11.255.255262,142
490.12.0.0/1490.12.0.1 to 90.15.255.25490.15.255.255262,142
590.16.0.0/1490.16.0.1 to 90.19.255.25490.19.255.255262,142
690.20.0.0/1490.20.0.1 to 90.23.255.25490.23.255.255262,142
790.24.0.0/1490.24.0.1 to 90.27.255.25490.27.255.255262,142
890.28.0.0/1490.28.0.1 to 90.31.255.25490.31.255.255262,142
990.32.0.0/1490.32.0.1 to 90.35.255.25490.35.255.255262,142
1090.36.0.0/1490.36.0.1 to 90.39.255.25490.39.255.255262,142
1190.40.0.0/1490.40.0.1 to 90.43.255.25490.43.255.255262,142
1290.44.0.0/1490.44.0.1 to 90.47.255.25490.47.255.255262,142
1390.48.0.0/1490.48.0.1 to 90.51.255.25490.51.255.255262,142
1490.52.0.0/1490.52.0.1 to 90.55.255.25490.55.255.255262,142
1590.56.0.0/1490.56.0.1 to 90.59.255.25490.59.255.255262,142
1690.60.0.0/1490.60.0.1 to 90.63.255.25490.63.255.255262,142
1790.64.0.0/1490.64.0.1 to 90.67.255.25490.67.255.255262,142
1890.68.0.0/1490.68.0.1 to 90.71.255.25490.71.255.255262,142
1990.72.0.0/1490.72.0.1 to 90.75.255.25490.75.255.255262,142
2090.76.0.0/1490.76.0.1 to 90.79.255.25490.79.255.255262,142
2190.80.0.0/1490.80.0.1 to 90.83.255.25490.83.255.255262,142
2290.84.0.0/1490.84.0.1 to 90.87.255.25490.87.255.255262,142
2390.88.0.0/1490.88.0.1 to 90.91.255.25490.91.255.255262,142
2490.92.0.0/1490.92.0.1 to 90.95.255.25490.95.255.255262,142
2590.96.0.0/1490.96.0.1 to 90.99.255.25490.99.255.255262,142
2690.100.0.0/1490.100.0.1 to 90.103.255.25490.103.255.255262,142
2790.104.0.0/1490.104.0.1 to 90.107.255.25490.107.255.255262,142
2890.108.0.0/1490.108.0.1 to 90.111.255.25490.111.255.255262,142
2990.112.0.0/1490.112.0.1 to 90.115.255.25490.115.255.255262,142
3090.116.0.0/1490.116.0.1 to 90.119.255.25490.119.255.255262,142
3190.120.0.0/1490.120.0.1 to 90.123.255.25490.123.255.255262,142
3290.124.0.0/1490.124.0.1 to 90.127.255.25490.127.255.255262,142
3390.128.0.0/1490.128.0.1 to 90.131.255.25490.131.255.255262,142
3490.132.0.0/1490.132.0.1 to 90.135.255.25490.135.255.255262,142
3590.136.0.0/1490.136.0.1 to 90.139.255.25490.139.255.255262,142
3690.140.0.0/1490.140.0.1 to 90.143.255.25490.143.255.255262,142
3790.144.0.0/1490.144.0.1 to 90.147.255.25490.147.255.255262,142
3890.148.0.0/1490.148.0.1 to 90.151.255.25490.151.255.255262,142
3990.152.0.0/1490.152.0.1 to 90.155.255.25490.155.255.255262,142
4090.156.0.0/1490.156.0.1 to 90.159.255.25490.159.255.255262,142
4190.160.0.0/1490.160.0.1 to 90.163.255.25490.163.255.255262,142
4290.164.0.0/1490.164.0.1 to 90.167.255.25490.167.255.255262,142
4390.168.0.0/1490.168.0.1 to 90.171.255.25490.171.255.255262,142
4490.172.0.0/1490.172.0.1 to 90.175.255.25490.175.255.255262,142
4590.176.0.0/1490.176.0.1 to 90.179.255.25490.179.255.255262,142
4690.180.0.0/1490.180.0.1 to 90.183.255.25490.183.255.255262,142
4790.184.0.0/1490.184.0.1 to 90.187.255.25490.187.255.255262,142
4890.188.0.0/1490.188.0.1 to 90.191.255.25490.191.255.255262,142
4990.192.0.0/1490.192.0.1 to 90.195.255.25490.195.255.255262,142
5090.196.0.0/1490.196.0.1 to 90.199.255.25490.199.255.255262,142
5190.200.0.0/1490.200.0.1 to 90.203.255.25490.203.255.255262,142
5290.204.0.0/1490.204.0.1 to 90.207.255.25490.207.255.255262,142
5390.208.0.0/1490.208.0.1 to 90.211.255.25490.211.255.255262,142
5490.212.0.0/1490.212.0.1 to 90.215.255.25490.215.255.255262,142
5590.216.0.0/1490.216.0.1 to 90.219.255.25490.219.255.255262,142
5690.220.0.0/1490.220.0.1 to 90.223.255.25490.223.255.255262,142
5790.224.0.0/1490.224.0.1 to 90.227.255.25490.227.255.255262,142
5890.228.0.0/1490.228.0.1 to 90.231.255.25490.231.255.255262,142
5990.232.0.0/1490.232.0.1 to 90.235.255.25490.235.255.255262,142
6090.236.0.0/1490.236.0.1 to 90.239.255.25490.239.255.255262,142
6190.240.0.0/1490.240.0.1 to 90.243.255.25490.243.255.255262,142
6290.244.0.0/1490.244.0.1 to 90.247.255.25490.247.255.255262,142
6390.248.0.0/1490.248.0.1 to 90.251.255.25490.251.255.255262,142
6490.252.0.0/1490.252.0.1 to 90.255.255.25490.255.255.255262,142
6591.0.0.0/1491.0.0.1 to 91.3.255.25491.3.255.255262,142
6691.4.0.0/1491.4.0.1 to 91.7.255.25491.7.255.255262,142
6791.8.0.0/1491.8.0.1 to 91.11.255.25491.11.255.255262,142
6891.12.0.0/1491.12.0.1 to 91.15.255.25491.15.255.255262,142
6991.16.0.0/1491.16.0.1 to 91.19.255.25491.19.255.255262,142
7091.20.0.0/1491.20.0.1 to 91.23.255.25491.23.255.255262,142
7191.24.0.0/1491.24.0.1 to 91.27.255.25491.27.255.255262,142
7291.28.0.0/1491.28.0.1 to 91.31.255.25491.31.255.255262,142
7391.32.0.0/1491.32.0.1 to 91.35.255.25491.35.255.255262,142
7491.36.0.0/1491.36.0.1 to 91.39.255.25491.39.255.255262,142
7591.40.0.0/1491.40.0.1 to 91.43.255.25491.43.255.255262,142
7691.44.0.0/1491.44.0.1 to 91.47.255.25491.47.255.255262,142
7791.48.0.0/1491.48.0.1 to 91.51.255.25491.51.255.255262,142
7891.52.0.0/1491.52.0.1 to 91.55.255.25491.55.255.255262,142
7991.56.0.0/1491.56.0.1 to 91.59.255.25491.59.255.255262,142
8091.60.0.0/1491.60.0.1 to 91.63.255.25491.63.255.255262,142
8191.64.0.0/1491.64.0.1 to 91.67.255.25491.67.255.255262,142
8291.68.0.0/1491.68.0.1 to 91.71.255.25491.71.255.255262,142
8391.72.0.0/1491.72.0.1 to 91.75.255.25491.75.255.255262,142
8491.76.0.0/1491.76.0.1 to 91.79.255.25491.79.255.255262,142
8591.80.0.0/1491.80.0.1 to 91.83.255.25491.83.255.255262,142
8691.84.0.0/1491.84.0.1 to 91.87.255.25491.87.255.255262,142
8791.88.0.0/1491.88.0.1 to 91.91.255.25491.91.255.255262,142
8891.92.0.0/1491.92.0.1 to 91.95.255.25491.95.255.255262,142
8991.96.0.0/1491.96.0.1 to 91.99.255.25491.99.255.255262,142
9091.100.0.0/1491.100.0.1 to 91.103.255.25491.103.255.255262,142
9191.104.0.0/1491.104.0.1 to 91.107.255.25491.107.255.255262,142
9291.108.0.0/1491.108.0.1 to 91.111.255.25491.111.255.255262,142
9391.112.0.0/1491.112.0.1 to 91.115.255.25491.115.255.255262,142
9491.116.0.0/1491.116.0.1 to 91.119.255.25491.119.255.255262,142
9591.120.0.0/1491.120.0.1 to 91.123.255.25491.123.255.255262,142
9691.124.0.0/1491.124.0.1 to 91.127.255.25491.127.255.255262,142
9791.128.0.0/1491.128.0.1 to 91.131.255.25491.131.255.255262,142
9891.132.0.0/1491.132.0.1 to 91.135.255.25491.135.255.255262,142
9991.136.0.0/1491.136.0.1 to 91.139.255.25491.139.255.255262,142
10091.140.0.0/1491.140.0.1 to 91.143.255.25491.143.255.255262,142
10191.144.0.0/1491.144.0.1 to 91.147.255.25491.147.255.255262,142
10291.148.0.0/1491.148.0.1 to 91.151.255.25491.151.255.255262,142
10391.152.0.0/1491.152.0.1 to 91.155.255.25491.155.255.255262,142
10491.156.0.0/1491.156.0.1 to 91.159.255.25491.159.255.255262,142
10591.160.0.0/1491.160.0.1 to 91.163.255.25491.163.255.255262,142
10691.164.0.0/1491.164.0.1 to 91.167.255.25491.167.255.255262,142
10791.168.0.0/1491.168.0.1 to 91.171.255.25491.171.255.255262,142
10891.172.0.0/1491.172.0.1 to 91.175.255.25491.175.255.255262,142
10991.176.0.0/1491.176.0.1 to 91.179.255.25491.179.255.255262,142
11091.180.0.0/1491.180.0.1 to 91.183.255.25491.183.255.255262,142
11191.184.0.0/1491.184.0.1 to 91.187.255.25491.187.255.255262,142
11291.188.0.0/1491.188.0.1 to 91.191.255.25491.191.255.255262,142
11391.192.0.0/1491.192.0.1 to 91.195.255.25491.195.255.255262,142
11491.196.0.0/1491.196.0.1 to 91.199.255.25491.199.255.255262,142
11591.200.0.0/1491.200.0.1 to 91.203.255.25491.203.255.255262,142
11691.204.0.0/1491.204.0.1 to 91.207.255.25491.207.255.255262,142
11791.208.0.0/1491.208.0.1 to 91.211.255.25491.211.255.255262,142
11891.212.0.0/1491.212.0.1 to 91.215.255.25491.215.255.255262,142
11991.216.0.0/1491.216.0.1 to 91.219.255.25491.219.255.255262,142
12091.220.0.0/1491.220.0.1 to 91.223.255.25491.223.255.255262,142
12191.224.0.0/1491.224.0.1 to 91.227.255.25491.227.255.255262,142
12291.228.0.0/1491.228.0.1 to 91.231.255.25491.231.255.255262,142
12391.232.0.0/1491.232.0.1 to 91.235.255.25491.235.255.255262,142
12491.236.0.0/1491.236.0.1 to 91.239.255.25491.239.255.255262,142
12591.240.0.0/1491.240.0.1 to 91.243.255.25491.243.255.255262,142
12691.244.0.0/1491.244.0.1 to 91.247.255.25491.247.255.255262,142
12791.248.0.0/1491.248.0.1 to 91.251.255.25491.251.255.255262,142
12891.252.0.0/1491.252.0.1 to 91.255.255.25491.255.255.255262,142

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