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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.

Network233.30.0.0/19
Usable hosts8,190
Subnet mask255.255.224.0
Addresses8,192
Network address
233.30.0.0
Broadcast address
233.30.31.255
First usable
233.30.0.1
Last usable
233.30.31.254
Usable hosts
8,190 (8,192 less the network and broadcast addresses)
Subnet mask
255.255.224.0
Wildcard mask
0.0.31.255 (Cisco ACLs, OSPF)
Prefix length
/19
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E91E0000 · Integer 3911057408 to 3911065599
Reverse DNS zones
0.30.233.in-addr.arpa
1.30.233.in-addr.arpa
2.30.233.in-addr.arpa
3.30.233.in-addr.arpa
4.30.233.in-addr.arpa
5.30.233.in-addr.arpa
6.30.233.in-addr.arpa
7.30.233.in-addr.arpa
8.30.233.in-addr.arpa
9.30.233.in-addr.arpa
10.30.233.in-addr.arpa
11.30.233.in-addr.arpa
12.30.233.in-addr.arpa
13.30.233.in-addr.arpa
14.30.233.in-addr.arpa
15.30.233.in-addr.arpa
and 16 more
/19 is not on a 8-bit boundary, so it takes 32 /24 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11101001.00011110.00000000.00000000233.30.0.0
Subnet mask11111111.11111111.11100000.00000000255.255.224.0
Network11101001.00011110.00000000.00000000233.30.0.0
Broadcast11101001.00011110.00011111.11111111233.30.31.255
Split into smaller subnets/26

233.30.0.0/19 makes 128 subnets of /26.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1233.30.0.0/26233.30.0.1 to 233.30.0.62233.30.0.6362
2233.30.0.64/26233.30.0.65 to 233.30.0.126233.30.0.12762
3233.30.0.128/26233.30.0.129 to 233.30.0.190233.30.0.19162
4233.30.0.192/26233.30.0.193 to 233.30.0.254233.30.0.25562
5233.30.1.0/26233.30.1.1 to 233.30.1.62233.30.1.6362
6233.30.1.64/26233.30.1.65 to 233.30.1.126233.30.1.12762
7233.30.1.128/26233.30.1.129 to 233.30.1.190233.30.1.19162
8233.30.1.192/26233.30.1.193 to 233.30.1.254233.30.1.25562
9233.30.2.0/26233.30.2.1 to 233.30.2.62233.30.2.6362
10233.30.2.64/26233.30.2.65 to 233.30.2.126233.30.2.12762
11233.30.2.128/26233.30.2.129 to 233.30.2.190233.30.2.19162
12233.30.2.192/26233.30.2.193 to 233.30.2.254233.30.2.25562
13233.30.3.0/26233.30.3.1 to 233.30.3.62233.30.3.6362
14233.30.3.64/26233.30.3.65 to 233.30.3.126233.30.3.12762
15233.30.3.128/26233.30.3.129 to 233.30.3.190233.30.3.19162
16233.30.3.192/26233.30.3.193 to 233.30.3.254233.30.3.25562
17233.30.4.0/26233.30.4.1 to 233.30.4.62233.30.4.6362
18233.30.4.64/26233.30.4.65 to 233.30.4.126233.30.4.12762
19233.30.4.128/26233.30.4.129 to 233.30.4.190233.30.4.19162
20233.30.4.192/26233.30.4.193 to 233.30.4.254233.30.4.25562
21233.30.5.0/26233.30.5.1 to 233.30.5.62233.30.5.6362
22233.30.5.64/26233.30.5.65 to 233.30.5.126233.30.5.12762
23233.30.5.128/26233.30.5.129 to 233.30.5.190233.30.5.19162
24233.30.5.192/26233.30.5.193 to 233.30.5.254233.30.5.25562
25233.30.6.0/26233.30.6.1 to 233.30.6.62233.30.6.6362
26233.30.6.64/26233.30.6.65 to 233.30.6.126233.30.6.12762
27233.30.6.128/26233.30.6.129 to 233.30.6.190233.30.6.19162
28233.30.6.192/26233.30.6.193 to 233.30.6.254233.30.6.25562
29233.30.7.0/26233.30.7.1 to 233.30.7.62233.30.7.6362
30233.30.7.64/26233.30.7.65 to 233.30.7.126233.30.7.12762
31233.30.7.128/26233.30.7.129 to 233.30.7.190233.30.7.19162
32233.30.7.192/26233.30.7.193 to 233.30.7.254233.30.7.25562
33233.30.8.0/26233.30.8.1 to 233.30.8.62233.30.8.6362
34233.30.8.64/26233.30.8.65 to 233.30.8.126233.30.8.12762
35233.30.8.128/26233.30.8.129 to 233.30.8.190233.30.8.19162
36233.30.8.192/26233.30.8.193 to 233.30.8.254233.30.8.25562
37233.30.9.0/26233.30.9.1 to 233.30.9.62233.30.9.6362
38233.30.9.64/26233.30.9.65 to 233.30.9.126233.30.9.12762
39233.30.9.128/26233.30.9.129 to 233.30.9.190233.30.9.19162
40233.30.9.192/26233.30.9.193 to 233.30.9.254233.30.9.25562
41233.30.10.0/26233.30.10.1 to 233.30.10.62233.30.10.6362
42233.30.10.64/26233.30.10.65 to 233.30.10.126233.30.10.12762
43233.30.10.128/26233.30.10.129 to 233.30.10.190233.30.10.19162
44233.30.10.192/26233.30.10.193 to 233.30.10.254233.30.10.25562
45233.30.11.0/26233.30.11.1 to 233.30.11.62233.30.11.6362
46233.30.11.64/26233.30.11.65 to 233.30.11.126233.30.11.12762
47233.30.11.128/26233.30.11.129 to 233.30.11.190233.30.11.19162
48233.30.11.192/26233.30.11.193 to 233.30.11.254233.30.11.25562
49233.30.12.0/26233.30.12.1 to 233.30.12.62233.30.12.6362
50233.30.12.64/26233.30.12.65 to 233.30.12.126233.30.12.12762
51233.30.12.128/26233.30.12.129 to 233.30.12.190233.30.12.19162
52233.30.12.192/26233.30.12.193 to 233.30.12.254233.30.12.25562
53233.30.13.0/26233.30.13.1 to 233.30.13.62233.30.13.6362
54233.30.13.64/26233.30.13.65 to 233.30.13.126233.30.13.12762
55233.30.13.128/26233.30.13.129 to 233.30.13.190233.30.13.19162
56233.30.13.192/26233.30.13.193 to 233.30.13.254233.30.13.25562
57233.30.14.0/26233.30.14.1 to 233.30.14.62233.30.14.6362
58233.30.14.64/26233.30.14.65 to 233.30.14.126233.30.14.12762
59233.30.14.128/26233.30.14.129 to 233.30.14.190233.30.14.19162
60233.30.14.192/26233.30.14.193 to 233.30.14.254233.30.14.25562
61233.30.15.0/26233.30.15.1 to 233.30.15.62233.30.15.6362
62233.30.15.64/26233.30.15.65 to 233.30.15.126233.30.15.12762
63233.30.15.128/26233.30.15.129 to 233.30.15.190233.30.15.19162
64233.30.15.192/26233.30.15.193 to 233.30.15.254233.30.15.25562
65233.30.16.0/26233.30.16.1 to 233.30.16.62233.30.16.6362
66233.30.16.64/26233.30.16.65 to 233.30.16.126233.30.16.12762
67233.30.16.128/26233.30.16.129 to 233.30.16.190233.30.16.19162
68233.30.16.192/26233.30.16.193 to 233.30.16.254233.30.16.25562
69233.30.17.0/26233.30.17.1 to 233.30.17.62233.30.17.6362
70233.30.17.64/26233.30.17.65 to 233.30.17.126233.30.17.12762
71233.30.17.128/26233.30.17.129 to 233.30.17.190233.30.17.19162
72233.30.17.192/26233.30.17.193 to 233.30.17.254233.30.17.25562
73233.30.18.0/26233.30.18.1 to 233.30.18.62233.30.18.6362
74233.30.18.64/26233.30.18.65 to 233.30.18.126233.30.18.12762
75233.30.18.128/26233.30.18.129 to 233.30.18.190233.30.18.19162
76233.30.18.192/26233.30.18.193 to 233.30.18.254233.30.18.25562
77233.30.19.0/26233.30.19.1 to 233.30.19.62233.30.19.6362
78233.30.19.64/26233.30.19.65 to 233.30.19.126233.30.19.12762
79233.30.19.128/26233.30.19.129 to 233.30.19.190233.30.19.19162
80233.30.19.192/26233.30.19.193 to 233.30.19.254233.30.19.25562
81233.30.20.0/26233.30.20.1 to 233.30.20.62233.30.20.6362
82233.30.20.64/26233.30.20.65 to 233.30.20.126233.30.20.12762
83233.30.20.128/26233.30.20.129 to 233.30.20.190233.30.20.19162
84233.30.20.192/26233.30.20.193 to 233.30.20.254233.30.20.25562
85233.30.21.0/26233.30.21.1 to 233.30.21.62233.30.21.6362
86233.30.21.64/26233.30.21.65 to 233.30.21.126233.30.21.12762
87233.30.21.128/26233.30.21.129 to 233.30.21.190233.30.21.19162
88233.30.21.192/26233.30.21.193 to 233.30.21.254233.30.21.25562
89233.30.22.0/26233.30.22.1 to 233.30.22.62233.30.22.6362
90233.30.22.64/26233.30.22.65 to 233.30.22.126233.30.22.12762
91233.30.22.128/26233.30.22.129 to 233.30.22.190233.30.22.19162
92233.30.22.192/26233.30.22.193 to 233.30.22.254233.30.22.25562
93233.30.23.0/26233.30.23.1 to 233.30.23.62233.30.23.6362
94233.30.23.64/26233.30.23.65 to 233.30.23.126233.30.23.12762
95233.30.23.128/26233.30.23.129 to 233.30.23.190233.30.23.19162
96233.30.23.192/26233.30.23.193 to 233.30.23.254233.30.23.25562
97233.30.24.0/26233.30.24.1 to 233.30.24.62233.30.24.6362
98233.30.24.64/26233.30.24.65 to 233.30.24.126233.30.24.12762
99233.30.24.128/26233.30.24.129 to 233.30.24.190233.30.24.19162
100233.30.24.192/26233.30.24.193 to 233.30.24.254233.30.24.25562
101233.30.25.0/26233.30.25.1 to 233.30.25.62233.30.25.6362
102233.30.25.64/26233.30.25.65 to 233.30.25.126233.30.25.12762
103233.30.25.128/26233.30.25.129 to 233.30.25.190233.30.25.19162
104233.30.25.192/26233.30.25.193 to 233.30.25.254233.30.25.25562
105233.30.26.0/26233.30.26.1 to 233.30.26.62233.30.26.6362
106233.30.26.64/26233.30.26.65 to 233.30.26.126233.30.26.12762
107233.30.26.128/26233.30.26.129 to 233.30.26.190233.30.26.19162
108233.30.26.192/26233.30.26.193 to 233.30.26.254233.30.26.25562
109233.30.27.0/26233.30.27.1 to 233.30.27.62233.30.27.6362
110233.30.27.64/26233.30.27.65 to 233.30.27.126233.30.27.12762
111233.30.27.128/26233.30.27.129 to 233.30.27.190233.30.27.19162
112233.30.27.192/26233.30.27.193 to 233.30.27.254233.30.27.25562
113233.30.28.0/26233.30.28.1 to 233.30.28.62233.30.28.6362
114233.30.28.64/26233.30.28.65 to 233.30.28.126233.30.28.12762
115233.30.28.128/26233.30.28.129 to 233.30.28.190233.30.28.19162
116233.30.28.192/26233.30.28.193 to 233.30.28.254233.30.28.25562
117233.30.29.0/26233.30.29.1 to 233.30.29.62233.30.29.6362
118233.30.29.64/26233.30.29.65 to 233.30.29.126233.30.29.12762
119233.30.29.128/26233.30.29.129 to 233.30.29.190233.30.29.19162
120233.30.29.192/26233.30.29.193 to 233.30.29.254233.30.29.25562
121233.30.30.0/26233.30.30.1 to 233.30.30.62233.30.30.6362
122233.30.30.64/26233.30.30.65 to 233.30.30.126233.30.30.12762
123233.30.30.128/26233.30.30.129 to 233.30.30.190233.30.30.19162
124233.30.30.192/26233.30.30.193 to 233.30.30.254233.30.30.25562
125233.30.31.0/26233.30.31.1 to 233.30.31.62233.30.31.6362
126233.30.31.64/26233.30.31.65 to 233.30.31.126233.30.31.12762
127233.30.31.128/26233.30.31.129 to 233.30.31.190233.30.31.19162
128233.30.31.192/26233.30.31.193 to 233.30.31.254233.30.31.25562

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