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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.

Network3.95.80.0/20
Usable hosts4,094
Subnet mask255.255.240.0
Addresses4,096
Network address
3.95.80.0
Broadcast address
3.95.95.255
First usable
3.95.80.1
Last usable
3.95.95.254
Usable hosts
4,094 (4,096 less the network and broadcast addresses)
Subnet mask
255.255.240.0
Wildcard mask
0.0.15.255 (Cisco ACLs, OSPF)
Prefix length
/20
Type
Public public
Old class
A (default /8)
As numbers
Hex 035F5000 · Integer 56578048 to 56582143
Reverse DNS zones
80.95.3.in-addr.arpa
81.95.3.in-addr.arpa
82.95.3.in-addr.arpa
83.95.3.in-addr.arpa
84.95.3.in-addr.arpa
85.95.3.in-addr.arpa
86.95.3.in-addr.arpa
87.95.3.in-addr.arpa
88.95.3.in-addr.arpa
89.95.3.in-addr.arpa
90.95.3.in-addr.arpa
91.95.3.in-addr.arpa
92.95.3.in-addr.arpa
93.95.3.in-addr.arpa
94.95.3.in-addr.arpa
95.95.3.in-addr.arpa
/20 is not on a 8-bit boundary, so it takes 16 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address00000011.01011111.01010000.000000003.95.80.0
Subnet mask11111111.11111111.11110000.00000000255.255.240.0
Network00000011.01011111.01010000.000000003.95.80.0
Broadcast00000011.01011111.01011111.111111113.95.95.255
Split into smaller subnets/27

3.95.80.0/20 makes 128 subnets of /27.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
13.95.80.0/273.95.80.1 to 3.95.80.303.95.80.3130
23.95.80.32/273.95.80.33 to 3.95.80.623.95.80.6330
33.95.80.64/273.95.80.65 to 3.95.80.943.95.80.9530
43.95.80.96/273.95.80.97 to 3.95.80.1263.95.80.12730
53.95.80.128/273.95.80.129 to 3.95.80.1583.95.80.15930
63.95.80.160/273.95.80.161 to 3.95.80.1903.95.80.19130
73.95.80.192/273.95.80.193 to 3.95.80.2223.95.80.22330
83.95.80.224/273.95.80.225 to 3.95.80.2543.95.80.25530
93.95.81.0/273.95.81.1 to 3.95.81.303.95.81.3130
103.95.81.32/273.95.81.33 to 3.95.81.623.95.81.6330
113.95.81.64/273.95.81.65 to 3.95.81.943.95.81.9530
123.95.81.96/273.95.81.97 to 3.95.81.1263.95.81.12730
133.95.81.128/273.95.81.129 to 3.95.81.1583.95.81.15930
143.95.81.160/273.95.81.161 to 3.95.81.1903.95.81.19130
153.95.81.192/273.95.81.193 to 3.95.81.2223.95.81.22330
163.95.81.224/273.95.81.225 to 3.95.81.2543.95.81.25530
173.95.82.0/273.95.82.1 to 3.95.82.303.95.82.3130
183.95.82.32/273.95.82.33 to 3.95.82.623.95.82.6330
193.95.82.64/273.95.82.65 to 3.95.82.943.95.82.9530
203.95.82.96/273.95.82.97 to 3.95.82.1263.95.82.12730
213.95.82.128/273.95.82.129 to 3.95.82.1583.95.82.15930
223.95.82.160/273.95.82.161 to 3.95.82.1903.95.82.19130
233.95.82.192/273.95.82.193 to 3.95.82.2223.95.82.22330
243.95.82.224/273.95.82.225 to 3.95.82.2543.95.82.25530
253.95.83.0/273.95.83.1 to 3.95.83.303.95.83.3130
263.95.83.32/273.95.83.33 to 3.95.83.623.95.83.6330
273.95.83.64/273.95.83.65 to 3.95.83.943.95.83.9530
283.95.83.96/273.95.83.97 to 3.95.83.1263.95.83.12730
293.95.83.128/273.95.83.129 to 3.95.83.1583.95.83.15930
303.95.83.160/273.95.83.161 to 3.95.83.1903.95.83.19130
313.95.83.192/273.95.83.193 to 3.95.83.2223.95.83.22330
323.95.83.224/273.95.83.225 to 3.95.83.2543.95.83.25530
333.95.84.0/273.95.84.1 to 3.95.84.303.95.84.3130
343.95.84.32/273.95.84.33 to 3.95.84.623.95.84.6330
353.95.84.64/273.95.84.65 to 3.95.84.943.95.84.9530
363.95.84.96/273.95.84.97 to 3.95.84.1263.95.84.12730
373.95.84.128/273.95.84.129 to 3.95.84.1583.95.84.15930
383.95.84.160/273.95.84.161 to 3.95.84.1903.95.84.19130
393.95.84.192/273.95.84.193 to 3.95.84.2223.95.84.22330
403.95.84.224/273.95.84.225 to 3.95.84.2543.95.84.25530
413.95.85.0/273.95.85.1 to 3.95.85.303.95.85.3130
423.95.85.32/273.95.85.33 to 3.95.85.623.95.85.6330
433.95.85.64/273.95.85.65 to 3.95.85.943.95.85.9530
443.95.85.96/273.95.85.97 to 3.95.85.1263.95.85.12730
453.95.85.128/273.95.85.129 to 3.95.85.1583.95.85.15930
463.95.85.160/273.95.85.161 to 3.95.85.1903.95.85.19130
473.95.85.192/273.95.85.193 to 3.95.85.2223.95.85.22330
483.95.85.224/273.95.85.225 to 3.95.85.2543.95.85.25530
493.95.86.0/273.95.86.1 to 3.95.86.303.95.86.3130
503.95.86.32/273.95.86.33 to 3.95.86.623.95.86.6330
513.95.86.64/273.95.86.65 to 3.95.86.943.95.86.9530
523.95.86.96/273.95.86.97 to 3.95.86.1263.95.86.12730
533.95.86.128/273.95.86.129 to 3.95.86.1583.95.86.15930
543.95.86.160/273.95.86.161 to 3.95.86.1903.95.86.19130
553.95.86.192/273.95.86.193 to 3.95.86.2223.95.86.22330
563.95.86.224/273.95.86.225 to 3.95.86.2543.95.86.25530
573.95.87.0/273.95.87.1 to 3.95.87.303.95.87.3130
583.95.87.32/273.95.87.33 to 3.95.87.623.95.87.6330
593.95.87.64/273.95.87.65 to 3.95.87.943.95.87.9530
603.95.87.96/273.95.87.97 to 3.95.87.1263.95.87.12730
613.95.87.128/273.95.87.129 to 3.95.87.1583.95.87.15930
623.95.87.160/273.95.87.161 to 3.95.87.1903.95.87.19130
633.95.87.192/273.95.87.193 to 3.95.87.2223.95.87.22330
643.95.87.224/273.95.87.225 to 3.95.87.2543.95.87.25530
653.95.88.0/273.95.88.1 to 3.95.88.303.95.88.3130
663.95.88.32/273.95.88.33 to 3.95.88.623.95.88.6330
673.95.88.64/273.95.88.65 to 3.95.88.943.95.88.9530
683.95.88.96/273.95.88.97 to 3.95.88.1263.95.88.12730
693.95.88.128/273.95.88.129 to 3.95.88.1583.95.88.15930
703.95.88.160/273.95.88.161 to 3.95.88.1903.95.88.19130
713.95.88.192/273.95.88.193 to 3.95.88.2223.95.88.22330
723.95.88.224/273.95.88.225 to 3.95.88.2543.95.88.25530
733.95.89.0/273.95.89.1 to 3.95.89.303.95.89.3130
743.95.89.32/273.95.89.33 to 3.95.89.623.95.89.6330
753.95.89.64/273.95.89.65 to 3.95.89.943.95.89.9530
763.95.89.96/273.95.89.97 to 3.95.89.1263.95.89.12730
773.95.89.128/273.95.89.129 to 3.95.89.1583.95.89.15930
783.95.89.160/273.95.89.161 to 3.95.89.1903.95.89.19130
793.95.89.192/273.95.89.193 to 3.95.89.2223.95.89.22330
803.95.89.224/273.95.89.225 to 3.95.89.2543.95.89.25530
813.95.90.0/273.95.90.1 to 3.95.90.303.95.90.3130
823.95.90.32/273.95.90.33 to 3.95.90.623.95.90.6330
833.95.90.64/273.95.90.65 to 3.95.90.943.95.90.9530
843.95.90.96/273.95.90.97 to 3.95.90.1263.95.90.12730
853.95.90.128/273.95.90.129 to 3.95.90.1583.95.90.15930
863.95.90.160/273.95.90.161 to 3.95.90.1903.95.90.19130
873.95.90.192/273.95.90.193 to 3.95.90.2223.95.90.22330
883.95.90.224/273.95.90.225 to 3.95.90.2543.95.90.25530
893.95.91.0/273.95.91.1 to 3.95.91.303.95.91.3130
903.95.91.32/273.95.91.33 to 3.95.91.623.95.91.6330
913.95.91.64/273.95.91.65 to 3.95.91.943.95.91.9530
923.95.91.96/273.95.91.97 to 3.95.91.1263.95.91.12730
933.95.91.128/273.95.91.129 to 3.95.91.1583.95.91.15930
943.95.91.160/273.95.91.161 to 3.95.91.1903.95.91.19130
953.95.91.192/273.95.91.193 to 3.95.91.2223.95.91.22330
963.95.91.224/273.95.91.225 to 3.95.91.2543.95.91.25530
973.95.92.0/273.95.92.1 to 3.95.92.303.95.92.3130
983.95.92.32/273.95.92.33 to 3.95.92.623.95.92.6330
993.95.92.64/273.95.92.65 to 3.95.92.943.95.92.9530
1003.95.92.96/273.95.92.97 to 3.95.92.1263.95.92.12730
1013.95.92.128/273.95.92.129 to 3.95.92.1583.95.92.15930
1023.95.92.160/273.95.92.161 to 3.95.92.1903.95.92.19130
1033.95.92.192/273.95.92.193 to 3.95.92.2223.95.92.22330
1043.95.92.224/273.95.92.225 to 3.95.92.2543.95.92.25530
1053.95.93.0/273.95.93.1 to 3.95.93.303.95.93.3130
1063.95.93.32/273.95.93.33 to 3.95.93.623.95.93.6330
1073.95.93.64/273.95.93.65 to 3.95.93.943.95.93.9530
1083.95.93.96/273.95.93.97 to 3.95.93.1263.95.93.12730
1093.95.93.128/273.95.93.129 to 3.95.93.1583.95.93.15930
1103.95.93.160/273.95.93.161 to 3.95.93.1903.95.93.19130
1113.95.93.192/273.95.93.193 to 3.95.93.2223.95.93.22330
1123.95.93.224/273.95.93.225 to 3.95.93.2543.95.93.25530
1133.95.94.0/273.95.94.1 to 3.95.94.303.95.94.3130
1143.95.94.32/273.95.94.33 to 3.95.94.623.95.94.6330
1153.95.94.64/273.95.94.65 to 3.95.94.943.95.94.9530
1163.95.94.96/273.95.94.97 to 3.95.94.1263.95.94.12730
1173.95.94.128/273.95.94.129 to 3.95.94.1583.95.94.15930
1183.95.94.160/273.95.94.161 to 3.95.94.1903.95.94.19130
1193.95.94.192/273.95.94.193 to 3.95.94.2223.95.94.22330
1203.95.94.224/273.95.94.225 to 3.95.94.2543.95.94.25530
1213.95.95.0/273.95.95.1 to 3.95.95.303.95.95.3130
1223.95.95.32/273.95.95.33 to 3.95.95.623.95.95.6330
1233.95.95.64/273.95.95.65 to 3.95.95.943.95.95.9530
1243.95.95.96/273.95.95.97 to 3.95.95.1263.95.95.12730
1253.95.95.128/273.95.95.129 to 3.95.95.1583.95.95.15930
1263.95.95.160/273.95.95.161 to 3.95.95.1903.95.95.19130
1273.95.95.192/273.95.95.193 to 3.95.95.2223.95.95.22330
1283.95.95.224/273.95.95.225 to 3.95.95.2543.95.95.25530

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