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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.

Network196.48.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
196.48.0.0
Broadcast address
196.55.255.255
First usable
196.48.0.1
Last usable
196.55.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
C (default /24)
As numbers
Hex C4300000 · Integer 3291480064 to 3292004351
Reverse DNS zones
48.196.in-addr.arpa
49.196.in-addr.arpa
50.196.in-addr.arpa
51.196.in-addr.arpa
52.196.in-addr.arpa
53.196.in-addr.arpa
54.196.in-addr.arpa
55.196.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11000100.00110000.00000000.00000000196.48.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network11000100.00110000.00000000.00000000196.48.0.0
Broadcast11000100.00110111.11111111.11111111196.55.255.255
Split into smaller subnets/19

196.48.0.0/13 makes 64 subnets of /19.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1196.48.0.0/19196.48.0.1 to 196.48.31.254196.48.31.2558,190
2196.48.32.0/19196.48.32.1 to 196.48.63.254196.48.63.2558,190
3196.48.64.0/19196.48.64.1 to 196.48.95.254196.48.95.2558,190
4196.48.96.0/19196.48.96.1 to 196.48.127.254196.48.127.2558,190
5196.48.128.0/19196.48.128.1 to 196.48.159.254196.48.159.2558,190
6196.48.160.0/19196.48.160.1 to 196.48.191.254196.48.191.2558,190
7196.48.192.0/19196.48.192.1 to 196.48.223.254196.48.223.2558,190
8196.48.224.0/19196.48.224.1 to 196.48.255.254196.48.255.2558,190
9196.49.0.0/19196.49.0.1 to 196.49.31.254196.49.31.2558,190
10196.49.32.0/19196.49.32.1 to 196.49.63.254196.49.63.2558,190
11196.49.64.0/19196.49.64.1 to 196.49.95.254196.49.95.2558,190
12196.49.96.0/19196.49.96.1 to 196.49.127.254196.49.127.2558,190
13196.49.128.0/19196.49.128.1 to 196.49.159.254196.49.159.2558,190
14196.49.160.0/19196.49.160.1 to 196.49.191.254196.49.191.2558,190
15196.49.192.0/19196.49.192.1 to 196.49.223.254196.49.223.2558,190
16196.49.224.0/19196.49.224.1 to 196.49.255.254196.49.255.2558,190
17196.50.0.0/19196.50.0.1 to 196.50.31.254196.50.31.2558,190
18196.50.32.0/19196.50.32.1 to 196.50.63.254196.50.63.2558,190
19196.50.64.0/19196.50.64.1 to 196.50.95.254196.50.95.2558,190
20196.50.96.0/19196.50.96.1 to 196.50.127.254196.50.127.2558,190
21196.50.128.0/19196.50.128.1 to 196.50.159.254196.50.159.2558,190
22196.50.160.0/19196.50.160.1 to 196.50.191.254196.50.191.2558,190
23196.50.192.0/19196.50.192.1 to 196.50.223.254196.50.223.2558,190
24196.50.224.0/19196.50.224.1 to 196.50.255.254196.50.255.2558,190
25196.51.0.0/19196.51.0.1 to 196.51.31.254196.51.31.2558,190
26196.51.32.0/19196.51.32.1 to 196.51.63.254196.51.63.2558,190
27196.51.64.0/19196.51.64.1 to 196.51.95.254196.51.95.2558,190
28196.51.96.0/19196.51.96.1 to 196.51.127.254196.51.127.2558,190
29196.51.128.0/19196.51.128.1 to 196.51.159.254196.51.159.2558,190
30196.51.160.0/19196.51.160.1 to 196.51.191.254196.51.191.2558,190
31196.51.192.0/19196.51.192.1 to 196.51.223.254196.51.223.2558,190
32196.51.224.0/19196.51.224.1 to 196.51.255.254196.51.255.2558,190
33196.52.0.0/19196.52.0.1 to 196.52.31.254196.52.31.2558,190
34196.52.32.0/19196.52.32.1 to 196.52.63.254196.52.63.2558,190
35196.52.64.0/19196.52.64.1 to 196.52.95.254196.52.95.2558,190
36196.52.96.0/19196.52.96.1 to 196.52.127.254196.52.127.2558,190
37196.52.128.0/19196.52.128.1 to 196.52.159.254196.52.159.2558,190
38196.52.160.0/19196.52.160.1 to 196.52.191.254196.52.191.2558,190
39196.52.192.0/19196.52.192.1 to 196.52.223.254196.52.223.2558,190
40196.52.224.0/19196.52.224.1 to 196.52.255.254196.52.255.2558,190
41196.53.0.0/19196.53.0.1 to 196.53.31.254196.53.31.2558,190
42196.53.32.0/19196.53.32.1 to 196.53.63.254196.53.63.2558,190
43196.53.64.0/19196.53.64.1 to 196.53.95.254196.53.95.2558,190
44196.53.96.0/19196.53.96.1 to 196.53.127.254196.53.127.2558,190
45196.53.128.0/19196.53.128.1 to 196.53.159.254196.53.159.2558,190
46196.53.160.0/19196.53.160.1 to 196.53.191.254196.53.191.2558,190
47196.53.192.0/19196.53.192.1 to 196.53.223.254196.53.223.2558,190
48196.53.224.0/19196.53.224.1 to 196.53.255.254196.53.255.2558,190
49196.54.0.0/19196.54.0.1 to 196.54.31.254196.54.31.2558,190
50196.54.32.0/19196.54.32.1 to 196.54.63.254196.54.63.2558,190
51196.54.64.0/19196.54.64.1 to 196.54.95.254196.54.95.2558,190
52196.54.96.0/19196.54.96.1 to 196.54.127.254196.54.127.2558,190
53196.54.128.0/19196.54.128.1 to 196.54.159.254196.54.159.2558,190
54196.54.160.0/19196.54.160.1 to 196.54.191.254196.54.191.2558,190
55196.54.192.0/19196.54.192.1 to 196.54.223.254196.54.223.2558,190
56196.54.224.0/19196.54.224.1 to 196.54.255.254196.54.255.2558,190
57196.55.0.0/19196.55.0.1 to 196.55.31.254196.55.31.2558,190
58196.55.32.0/19196.55.32.1 to 196.55.63.254196.55.63.2558,190
59196.55.64.0/19196.55.64.1 to 196.55.95.254196.55.95.2558,190
60196.55.96.0/19196.55.96.1 to 196.55.127.254196.55.127.2558,190
61196.55.128.0/19196.55.128.1 to 196.55.159.254196.55.159.2558,190
62196.55.160.0/19196.55.160.1 to 196.55.191.254196.55.191.2558,190
63196.55.192.0/19196.55.192.1 to 196.55.223.254196.55.223.2558,190
64196.55.224.0/19196.55.224.1 to 196.55.255.254196.55.255.2558,190

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