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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.

Network75.98.0.0/17
Usable hosts32,766
Subnet mask255.255.128.0
Addresses32,768
Network address
75.98.0.0
Broadcast address
75.98.127.255
First usable
75.98.0.1
Last usable
75.98.127.254
Usable hosts
32,766 (32,768 less the network and broadcast addresses)
Subnet mask
255.255.128.0
Wildcard mask
0.0.127.255 (Cisco ACLs, OSPF)
Prefix length
/17
Type
Public public
Old class
A (default /8)
As numbers
Hex 4B620000 · Integer 1264713728 to 1264746495
Reverse DNS zones
0.98.75.in-addr.arpa
1.98.75.in-addr.arpa
2.98.75.in-addr.arpa
3.98.75.in-addr.arpa
4.98.75.in-addr.arpa
5.98.75.in-addr.arpa
6.98.75.in-addr.arpa
7.98.75.in-addr.arpa
8.98.75.in-addr.arpa
9.98.75.in-addr.arpa
10.98.75.in-addr.arpa
11.98.75.in-addr.arpa
12.98.75.in-addr.arpa
13.98.75.in-addr.arpa
14.98.75.in-addr.arpa
15.98.75.in-addr.arpa
and 112 more
/17 is not on a 8-bit boundary, so it takes 128 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01001011.01100010.00000000.0000000075.98.0.0
Subnet mask11111111.11111111.10000000.00000000255.255.128.0
Network01001011.01100010.00000000.0000000075.98.0.0
Broadcast01001011.01100010.01111111.1111111175.98.127.255
Split into smaller subnets/24

75.98.0.0/17 makes 128 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
175.98.0.0/2475.98.0.1 to 75.98.0.25475.98.0.255254
275.98.1.0/2475.98.1.1 to 75.98.1.25475.98.1.255254
375.98.2.0/2475.98.2.1 to 75.98.2.25475.98.2.255254
475.98.3.0/2475.98.3.1 to 75.98.3.25475.98.3.255254
575.98.4.0/2475.98.4.1 to 75.98.4.25475.98.4.255254
675.98.5.0/2475.98.5.1 to 75.98.5.25475.98.5.255254
775.98.6.0/2475.98.6.1 to 75.98.6.25475.98.6.255254
875.98.7.0/2475.98.7.1 to 75.98.7.25475.98.7.255254
975.98.8.0/2475.98.8.1 to 75.98.8.25475.98.8.255254
1075.98.9.0/2475.98.9.1 to 75.98.9.25475.98.9.255254
1175.98.10.0/2475.98.10.1 to 75.98.10.25475.98.10.255254
1275.98.11.0/2475.98.11.1 to 75.98.11.25475.98.11.255254
1375.98.12.0/2475.98.12.1 to 75.98.12.25475.98.12.255254
1475.98.13.0/2475.98.13.1 to 75.98.13.25475.98.13.255254
1575.98.14.0/2475.98.14.1 to 75.98.14.25475.98.14.255254
1675.98.15.0/2475.98.15.1 to 75.98.15.25475.98.15.255254
1775.98.16.0/2475.98.16.1 to 75.98.16.25475.98.16.255254
1875.98.17.0/2475.98.17.1 to 75.98.17.25475.98.17.255254
1975.98.18.0/2475.98.18.1 to 75.98.18.25475.98.18.255254
2075.98.19.0/2475.98.19.1 to 75.98.19.25475.98.19.255254
2175.98.20.0/2475.98.20.1 to 75.98.20.25475.98.20.255254
2275.98.21.0/2475.98.21.1 to 75.98.21.25475.98.21.255254
2375.98.22.0/2475.98.22.1 to 75.98.22.25475.98.22.255254
2475.98.23.0/2475.98.23.1 to 75.98.23.25475.98.23.255254
2575.98.24.0/2475.98.24.1 to 75.98.24.25475.98.24.255254
2675.98.25.0/2475.98.25.1 to 75.98.25.25475.98.25.255254
2775.98.26.0/2475.98.26.1 to 75.98.26.25475.98.26.255254
2875.98.27.0/2475.98.27.1 to 75.98.27.25475.98.27.255254
2975.98.28.0/2475.98.28.1 to 75.98.28.25475.98.28.255254
3075.98.29.0/2475.98.29.1 to 75.98.29.25475.98.29.255254
3175.98.30.0/2475.98.30.1 to 75.98.30.25475.98.30.255254
3275.98.31.0/2475.98.31.1 to 75.98.31.25475.98.31.255254
3375.98.32.0/2475.98.32.1 to 75.98.32.25475.98.32.255254
3475.98.33.0/2475.98.33.1 to 75.98.33.25475.98.33.255254
3575.98.34.0/2475.98.34.1 to 75.98.34.25475.98.34.255254
3675.98.35.0/2475.98.35.1 to 75.98.35.25475.98.35.255254
3775.98.36.0/2475.98.36.1 to 75.98.36.25475.98.36.255254
3875.98.37.0/2475.98.37.1 to 75.98.37.25475.98.37.255254
3975.98.38.0/2475.98.38.1 to 75.98.38.25475.98.38.255254
4075.98.39.0/2475.98.39.1 to 75.98.39.25475.98.39.255254
4175.98.40.0/2475.98.40.1 to 75.98.40.25475.98.40.255254
4275.98.41.0/2475.98.41.1 to 75.98.41.25475.98.41.255254
4375.98.42.0/2475.98.42.1 to 75.98.42.25475.98.42.255254
4475.98.43.0/2475.98.43.1 to 75.98.43.25475.98.43.255254
4575.98.44.0/2475.98.44.1 to 75.98.44.25475.98.44.255254
4675.98.45.0/2475.98.45.1 to 75.98.45.25475.98.45.255254
4775.98.46.0/2475.98.46.1 to 75.98.46.25475.98.46.255254
4875.98.47.0/2475.98.47.1 to 75.98.47.25475.98.47.255254
4975.98.48.0/2475.98.48.1 to 75.98.48.25475.98.48.255254
5075.98.49.0/2475.98.49.1 to 75.98.49.25475.98.49.255254
5175.98.50.0/2475.98.50.1 to 75.98.50.25475.98.50.255254
5275.98.51.0/2475.98.51.1 to 75.98.51.25475.98.51.255254
5375.98.52.0/2475.98.52.1 to 75.98.52.25475.98.52.255254
5475.98.53.0/2475.98.53.1 to 75.98.53.25475.98.53.255254
5575.98.54.0/2475.98.54.1 to 75.98.54.25475.98.54.255254
5675.98.55.0/2475.98.55.1 to 75.98.55.25475.98.55.255254
5775.98.56.0/2475.98.56.1 to 75.98.56.25475.98.56.255254
5875.98.57.0/2475.98.57.1 to 75.98.57.25475.98.57.255254
5975.98.58.0/2475.98.58.1 to 75.98.58.25475.98.58.255254
6075.98.59.0/2475.98.59.1 to 75.98.59.25475.98.59.255254
6175.98.60.0/2475.98.60.1 to 75.98.60.25475.98.60.255254
6275.98.61.0/2475.98.61.1 to 75.98.61.25475.98.61.255254
6375.98.62.0/2475.98.62.1 to 75.98.62.25475.98.62.255254
6475.98.63.0/2475.98.63.1 to 75.98.63.25475.98.63.255254
6575.98.64.0/2475.98.64.1 to 75.98.64.25475.98.64.255254
6675.98.65.0/2475.98.65.1 to 75.98.65.25475.98.65.255254
6775.98.66.0/2475.98.66.1 to 75.98.66.25475.98.66.255254
6875.98.67.0/2475.98.67.1 to 75.98.67.25475.98.67.255254
6975.98.68.0/2475.98.68.1 to 75.98.68.25475.98.68.255254
7075.98.69.0/2475.98.69.1 to 75.98.69.25475.98.69.255254
7175.98.70.0/2475.98.70.1 to 75.98.70.25475.98.70.255254
7275.98.71.0/2475.98.71.1 to 75.98.71.25475.98.71.255254
7375.98.72.0/2475.98.72.1 to 75.98.72.25475.98.72.255254
7475.98.73.0/2475.98.73.1 to 75.98.73.25475.98.73.255254
7575.98.74.0/2475.98.74.1 to 75.98.74.25475.98.74.255254
7675.98.75.0/2475.98.75.1 to 75.98.75.25475.98.75.255254
7775.98.76.0/2475.98.76.1 to 75.98.76.25475.98.76.255254
7875.98.77.0/2475.98.77.1 to 75.98.77.25475.98.77.255254
7975.98.78.0/2475.98.78.1 to 75.98.78.25475.98.78.255254
8075.98.79.0/2475.98.79.1 to 75.98.79.25475.98.79.255254
8175.98.80.0/2475.98.80.1 to 75.98.80.25475.98.80.255254
8275.98.81.0/2475.98.81.1 to 75.98.81.25475.98.81.255254
8375.98.82.0/2475.98.82.1 to 75.98.82.25475.98.82.255254
8475.98.83.0/2475.98.83.1 to 75.98.83.25475.98.83.255254
8575.98.84.0/2475.98.84.1 to 75.98.84.25475.98.84.255254
8675.98.85.0/2475.98.85.1 to 75.98.85.25475.98.85.255254
8775.98.86.0/2475.98.86.1 to 75.98.86.25475.98.86.255254
8875.98.87.0/2475.98.87.1 to 75.98.87.25475.98.87.255254
8975.98.88.0/2475.98.88.1 to 75.98.88.25475.98.88.255254
9075.98.89.0/2475.98.89.1 to 75.98.89.25475.98.89.255254
9175.98.90.0/2475.98.90.1 to 75.98.90.25475.98.90.255254
9275.98.91.0/2475.98.91.1 to 75.98.91.25475.98.91.255254
9375.98.92.0/2475.98.92.1 to 75.98.92.25475.98.92.255254
9475.98.93.0/2475.98.93.1 to 75.98.93.25475.98.93.255254
9575.98.94.0/2475.98.94.1 to 75.98.94.25475.98.94.255254
9675.98.95.0/2475.98.95.1 to 75.98.95.25475.98.95.255254
9775.98.96.0/2475.98.96.1 to 75.98.96.25475.98.96.255254
9875.98.97.0/2475.98.97.1 to 75.98.97.25475.98.97.255254
9975.98.98.0/2475.98.98.1 to 75.98.98.25475.98.98.255254
10075.98.99.0/2475.98.99.1 to 75.98.99.25475.98.99.255254
10175.98.100.0/2475.98.100.1 to 75.98.100.25475.98.100.255254
10275.98.101.0/2475.98.101.1 to 75.98.101.25475.98.101.255254
10375.98.102.0/2475.98.102.1 to 75.98.102.25475.98.102.255254
10475.98.103.0/2475.98.103.1 to 75.98.103.25475.98.103.255254
10575.98.104.0/2475.98.104.1 to 75.98.104.25475.98.104.255254
10675.98.105.0/2475.98.105.1 to 75.98.105.25475.98.105.255254
10775.98.106.0/2475.98.106.1 to 75.98.106.25475.98.106.255254
10875.98.107.0/2475.98.107.1 to 75.98.107.25475.98.107.255254
10975.98.108.0/2475.98.108.1 to 75.98.108.25475.98.108.255254
11075.98.109.0/2475.98.109.1 to 75.98.109.25475.98.109.255254
11175.98.110.0/2475.98.110.1 to 75.98.110.25475.98.110.255254
11275.98.111.0/2475.98.111.1 to 75.98.111.25475.98.111.255254
11375.98.112.0/2475.98.112.1 to 75.98.112.25475.98.112.255254
11475.98.113.0/2475.98.113.1 to 75.98.113.25475.98.113.255254
11575.98.114.0/2475.98.114.1 to 75.98.114.25475.98.114.255254
11675.98.115.0/2475.98.115.1 to 75.98.115.25475.98.115.255254
11775.98.116.0/2475.98.116.1 to 75.98.116.25475.98.116.255254
11875.98.117.0/2475.98.117.1 to 75.98.117.25475.98.117.255254
11975.98.118.0/2475.98.118.1 to 75.98.118.25475.98.118.255254
12075.98.119.0/2475.98.119.1 to 75.98.119.25475.98.119.255254
12175.98.120.0/2475.98.120.1 to 75.98.120.25475.98.120.255254
12275.98.121.0/2475.98.121.1 to 75.98.121.25475.98.121.255254
12375.98.122.0/2475.98.122.1 to 75.98.122.25475.98.122.255254
12475.98.123.0/2475.98.123.1 to 75.98.123.25475.98.123.255254
12575.98.124.0/2475.98.124.1 to 75.98.124.25475.98.124.255254
12675.98.125.0/2475.98.125.1 to 75.98.125.25475.98.125.255254
12775.98.126.0/2475.98.126.1 to 75.98.126.25475.98.126.255254
12875.98.127.0/2475.98.127.1 to 75.98.127.25475.98.127.255254

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