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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.

Network190.96.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
190.96.0.0
Broadcast address
190.127.255.255
First usable
190.96.0.1
Last usable
190.127.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Public public
Old class
B (default /16)
As numbers
Hex BE600000 · Integer 3193962496 to 3196059647
Reverse DNS zones
96.190.in-addr.arpa
97.190.in-addr.arpa
98.190.in-addr.arpa
99.190.in-addr.arpa
100.190.in-addr.arpa
101.190.in-addr.arpa
102.190.in-addr.arpa
103.190.in-addr.arpa
104.190.in-addr.arpa
105.190.in-addr.arpa
106.190.in-addr.arpa
107.190.in-addr.arpa
108.190.in-addr.arpa
109.190.in-addr.arpa
110.190.in-addr.arpa
111.190.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10111110.01100000.00000000.00000000190.96.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network10111110.01100000.00000000.00000000190.96.0.0
Broadcast10111110.01111111.11111111.11111111190.127.255.255
Split into smaller subnets/21
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

190.96.0.0/11 makes 1,024 subnets of /21; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1190.96.0.0/21190.96.0.1 to 190.96.7.254190.96.7.2552,046
2190.96.8.0/21190.96.8.1 to 190.96.15.254190.96.15.2552,046
3190.96.16.0/21190.96.16.1 to 190.96.23.254190.96.23.2552,046
4190.96.24.0/21190.96.24.1 to 190.96.31.254190.96.31.2552,046
5190.96.32.0/21190.96.32.1 to 190.96.39.254190.96.39.2552,046
6190.96.40.0/21190.96.40.1 to 190.96.47.254190.96.47.2552,046
7190.96.48.0/21190.96.48.1 to 190.96.55.254190.96.55.2552,046
8190.96.56.0/21190.96.56.1 to 190.96.63.254190.96.63.2552,046
9190.96.64.0/21190.96.64.1 to 190.96.71.254190.96.71.2552,046
10190.96.72.0/21190.96.72.1 to 190.96.79.254190.96.79.2552,046
11190.96.80.0/21190.96.80.1 to 190.96.87.254190.96.87.2552,046
12190.96.88.0/21190.96.88.1 to 190.96.95.254190.96.95.2552,046
13190.96.96.0/21190.96.96.1 to 190.96.103.254190.96.103.2552,046
14190.96.104.0/21190.96.104.1 to 190.96.111.254190.96.111.2552,046
15190.96.112.0/21190.96.112.1 to 190.96.119.254190.96.119.2552,046
16190.96.120.0/21190.96.120.1 to 190.96.127.254190.96.127.2552,046
17190.96.128.0/21190.96.128.1 to 190.96.135.254190.96.135.2552,046
18190.96.136.0/21190.96.136.1 to 190.96.143.254190.96.143.2552,046
19190.96.144.0/21190.96.144.1 to 190.96.151.254190.96.151.2552,046
20190.96.152.0/21190.96.152.1 to 190.96.159.254190.96.159.2552,046
21190.96.160.0/21190.96.160.1 to 190.96.167.254190.96.167.2552,046
22190.96.168.0/21190.96.168.1 to 190.96.175.254190.96.175.2552,046
23190.96.176.0/21190.96.176.1 to 190.96.183.254190.96.183.2552,046
24190.96.184.0/21190.96.184.1 to 190.96.191.254190.96.191.2552,046
25190.96.192.0/21190.96.192.1 to 190.96.199.254190.96.199.2552,046
26190.96.200.0/21190.96.200.1 to 190.96.207.254190.96.207.2552,046
27190.96.208.0/21190.96.208.1 to 190.96.215.254190.96.215.2552,046
28190.96.216.0/21190.96.216.1 to 190.96.223.254190.96.223.2552,046
29190.96.224.0/21190.96.224.1 to 190.96.231.254190.96.231.2552,046
30190.96.232.0/21190.96.232.1 to 190.96.239.254190.96.239.2552,046
31190.96.240.0/21190.96.240.1 to 190.96.247.254190.96.247.2552,046
32190.96.248.0/21190.96.248.1 to 190.96.255.254190.96.255.2552,046
33190.97.0.0/21190.97.0.1 to 190.97.7.254190.97.7.2552,046
34190.97.8.0/21190.97.8.1 to 190.97.15.254190.97.15.2552,046
35190.97.16.0/21190.97.16.1 to 190.97.23.254190.97.23.2552,046
36190.97.24.0/21190.97.24.1 to 190.97.31.254190.97.31.2552,046
37190.97.32.0/21190.97.32.1 to 190.97.39.254190.97.39.2552,046
38190.97.40.0/21190.97.40.1 to 190.97.47.254190.97.47.2552,046
39190.97.48.0/21190.97.48.1 to 190.97.55.254190.97.55.2552,046
40190.97.56.0/21190.97.56.1 to 190.97.63.254190.97.63.2552,046
41190.97.64.0/21190.97.64.1 to 190.97.71.254190.97.71.2552,046
42190.97.72.0/21190.97.72.1 to 190.97.79.254190.97.79.2552,046
43190.97.80.0/21190.97.80.1 to 190.97.87.254190.97.87.2552,046
44190.97.88.0/21190.97.88.1 to 190.97.95.254190.97.95.2552,046
45190.97.96.0/21190.97.96.1 to 190.97.103.254190.97.103.2552,046
46190.97.104.0/21190.97.104.1 to 190.97.111.254190.97.111.2552,046
47190.97.112.0/21190.97.112.1 to 190.97.119.254190.97.119.2552,046
48190.97.120.0/21190.97.120.1 to 190.97.127.254190.97.127.2552,046
49190.97.128.0/21190.97.128.1 to 190.97.135.254190.97.135.2552,046
50190.97.136.0/21190.97.136.1 to 190.97.143.254190.97.143.2552,046
51190.97.144.0/21190.97.144.1 to 190.97.151.254190.97.151.2552,046
52190.97.152.0/21190.97.152.1 to 190.97.159.254190.97.159.2552,046
53190.97.160.0/21190.97.160.1 to 190.97.167.254190.97.167.2552,046
54190.97.168.0/21190.97.168.1 to 190.97.175.254190.97.175.2552,046
55190.97.176.0/21190.97.176.1 to 190.97.183.254190.97.183.2552,046
56190.97.184.0/21190.97.184.1 to 190.97.191.254190.97.191.2552,046
57190.97.192.0/21190.97.192.1 to 190.97.199.254190.97.199.2552,046
58190.97.200.0/21190.97.200.1 to 190.97.207.254190.97.207.2552,046
59190.97.208.0/21190.97.208.1 to 190.97.215.254190.97.215.2552,046
60190.97.216.0/21190.97.216.1 to 190.97.223.254190.97.223.2552,046
61190.97.224.0/21190.97.224.1 to 190.97.231.254190.97.231.2552,046
62190.97.232.0/21190.97.232.1 to 190.97.239.254190.97.239.2552,046
63190.97.240.0/21190.97.240.1 to 190.97.247.254190.97.247.2552,046
64190.97.248.0/21190.97.248.1 to 190.97.255.254190.97.255.2552,046
65190.98.0.0/21190.98.0.1 to 190.98.7.254190.98.7.2552,046
66190.98.8.0/21190.98.8.1 to 190.98.15.254190.98.15.2552,046
67190.98.16.0/21190.98.16.1 to 190.98.23.254190.98.23.2552,046
68190.98.24.0/21190.98.24.1 to 190.98.31.254190.98.31.2552,046
69190.98.32.0/21190.98.32.1 to 190.98.39.254190.98.39.2552,046
70190.98.40.0/21190.98.40.1 to 190.98.47.254190.98.47.2552,046
71190.98.48.0/21190.98.48.1 to 190.98.55.254190.98.55.2552,046
72190.98.56.0/21190.98.56.1 to 190.98.63.254190.98.63.2552,046
73190.98.64.0/21190.98.64.1 to 190.98.71.254190.98.71.2552,046
74190.98.72.0/21190.98.72.1 to 190.98.79.254190.98.79.2552,046
75190.98.80.0/21190.98.80.1 to 190.98.87.254190.98.87.2552,046
76190.98.88.0/21190.98.88.1 to 190.98.95.254190.98.95.2552,046
77190.98.96.0/21190.98.96.1 to 190.98.103.254190.98.103.2552,046
78190.98.104.0/21190.98.104.1 to 190.98.111.254190.98.111.2552,046
79190.98.112.0/21190.98.112.1 to 190.98.119.254190.98.119.2552,046
80190.98.120.0/21190.98.120.1 to 190.98.127.254190.98.127.2552,046
81190.98.128.0/21190.98.128.1 to 190.98.135.254190.98.135.2552,046
82190.98.136.0/21190.98.136.1 to 190.98.143.254190.98.143.2552,046
83190.98.144.0/21190.98.144.1 to 190.98.151.254190.98.151.2552,046
84190.98.152.0/21190.98.152.1 to 190.98.159.254190.98.159.2552,046
85190.98.160.0/21190.98.160.1 to 190.98.167.254190.98.167.2552,046
86190.98.168.0/21190.98.168.1 to 190.98.175.254190.98.175.2552,046
87190.98.176.0/21190.98.176.1 to 190.98.183.254190.98.183.2552,046
88190.98.184.0/21190.98.184.1 to 190.98.191.254190.98.191.2552,046
89190.98.192.0/21190.98.192.1 to 190.98.199.254190.98.199.2552,046
90190.98.200.0/21190.98.200.1 to 190.98.207.254190.98.207.2552,046
91190.98.208.0/21190.98.208.1 to 190.98.215.254190.98.215.2552,046
92190.98.216.0/21190.98.216.1 to 190.98.223.254190.98.223.2552,046
93190.98.224.0/21190.98.224.1 to 190.98.231.254190.98.231.2552,046
94190.98.232.0/21190.98.232.1 to 190.98.239.254190.98.239.2552,046
95190.98.240.0/21190.98.240.1 to 190.98.247.254190.98.247.2552,046
96190.98.248.0/21190.98.248.1 to 190.98.255.254190.98.255.2552,046
97190.99.0.0/21190.99.0.1 to 190.99.7.254190.99.7.2552,046
98190.99.8.0/21190.99.8.1 to 190.99.15.254190.99.15.2552,046
99190.99.16.0/21190.99.16.1 to 190.99.23.254190.99.23.2552,046
100190.99.24.0/21190.99.24.1 to 190.99.31.254190.99.31.2552,046
101190.99.32.0/21190.99.32.1 to 190.99.39.254190.99.39.2552,046
102190.99.40.0/21190.99.40.1 to 190.99.47.254190.99.47.2552,046
103190.99.48.0/21190.99.48.1 to 190.99.55.254190.99.55.2552,046
104190.99.56.0/21190.99.56.1 to 190.99.63.254190.99.63.2552,046
105190.99.64.0/21190.99.64.1 to 190.99.71.254190.99.71.2552,046
106190.99.72.0/21190.99.72.1 to 190.99.79.254190.99.79.2552,046
107190.99.80.0/21190.99.80.1 to 190.99.87.254190.99.87.2552,046
108190.99.88.0/21190.99.88.1 to 190.99.95.254190.99.95.2552,046
109190.99.96.0/21190.99.96.1 to 190.99.103.254190.99.103.2552,046
110190.99.104.0/21190.99.104.1 to 190.99.111.254190.99.111.2552,046
111190.99.112.0/21190.99.112.1 to 190.99.119.254190.99.119.2552,046
112190.99.120.0/21190.99.120.1 to 190.99.127.254190.99.127.2552,046
113190.99.128.0/21190.99.128.1 to 190.99.135.254190.99.135.2552,046
114190.99.136.0/21190.99.136.1 to 190.99.143.254190.99.143.2552,046
115190.99.144.0/21190.99.144.1 to 190.99.151.254190.99.151.2552,046
116190.99.152.0/21190.99.152.1 to 190.99.159.254190.99.159.2552,046
117190.99.160.0/21190.99.160.1 to 190.99.167.254190.99.167.2552,046
118190.99.168.0/21190.99.168.1 to 190.99.175.254190.99.175.2552,046
119190.99.176.0/21190.99.176.1 to 190.99.183.254190.99.183.2552,046
120190.99.184.0/21190.99.184.1 to 190.99.191.254190.99.191.2552,046
121190.99.192.0/21190.99.192.1 to 190.99.199.254190.99.199.2552,046
122190.99.200.0/21190.99.200.1 to 190.99.207.254190.99.207.2552,046
123190.99.208.0/21190.99.208.1 to 190.99.215.254190.99.215.2552,046
124190.99.216.0/21190.99.216.1 to 190.99.223.254190.99.223.2552,046
125190.99.224.0/21190.99.224.1 to 190.99.231.254190.99.231.2552,046
126190.99.232.0/21190.99.232.1 to 190.99.239.254190.99.239.2552,046
127190.99.240.0/21190.99.240.1 to 190.99.247.254190.99.247.2552,046
128190.99.248.0/21190.99.248.1 to 190.99.255.254190.99.255.2552,046
129190.100.0.0/21190.100.0.1 to 190.100.7.254190.100.7.2552,046
130190.100.8.0/21190.100.8.1 to 190.100.15.254190.100.15.2552,046
131190.100.16.0/21190.100.16.1 to 190.100.23.254190.100.23.2552,046
132190.100.24.0/21190.100.24.1 to 190.100.31.254190.100.31.2552,046
133190.100.32.0/21190.100.32.1 to 190.100.39.254190.100.39.2552,046
134190.100.40.0/21190.100.40.1 to 190.100.47.254190.100.47.2552,046
135190.100.48.0/21190.100.48.1 to 190.100.55.254190.100.55.2552,046
136190.100.56.0/21190.100.56.1 to 190.100.63.254190.100.63.2552,046
137190.100.64.0/21190.100.64.1 to 190.100.71.254190.100.71.2552,046
138190.100.72.0/21190.100.72.1 to 190.100.79.254190.100.79.2552,046
139190.100.80.0/21190.100.80.1 to 190.100.87.254190.100.87.2552,046
140190.100.88.0/21190.100.88.1 to 190.100.95.254190.100.95.2552,046
141190.100.96.0/21190.100.96.1 to 190.100.103.254190.100.103.2552,046
142190.100.104.0/21190.100.104.1 to 190.100.111.254190.100.111.2552,046
143190.100.112.0/21190.100.112.1 to 190.100.119.254190.100.119.2552,046
144190.100.120.0/21190.100.120.1 to 190.100.127.254190.100.127.2552,046
145190.100.128.0/21190.100.128.1 to 190.100.135.254190.100.135.2552,046
146190.100.136.0/21190.100.136.1 to 190.100.143.254190.100.143.2552,046
147190.100.144.0/21190.100.144.1 to 190.100.151.254190.100.151.2552,046
148190.100.152.0/21190.100.152.1 to 190.100.159.254190.100.159.2552,046
149190.100.160.0/21190.100.160.1 to 190.100.167.254190.100.167.2552,046
150190.100.168.0/21190.100.168.1 to 190.100.175.254190.100.175.2552,046
151190.100.176.0/21190.100.176.1 to 190.100.183.254190.100.183.2552,046
152190.100.184.0/21190.100.184.1 to 190.100.191.254190.100.191.2552,046
153190.100.192.0/21190.100.192.1 to 190.100.199.254190.100.199.2552,046
154190.100.200.0/21190.100.200.1 to 190.100.207.254190.100.207.2552,046
155190.100.208.0/21190.100.208.1 to 190.100.215.254190.100.215.2552,046
156190.100.216.0/21190.100.216.1 to 190.100.223.254190.100.223.2552,046
157190.100.224.0/21190.100.224.1 to 190.100.231.254190.100.231.2552,046
158190.100.232.0/21190.100.232.1 to 190.100.239.254190.100.239.2552,046
159190.100.240.0/21190.100.240.1 to 190.100.247.254190.100.247.2552,046
160190.100.248.0/21190.100.248.1 to 190.100.255.254190.100.255.2552,046
161190.101.0.0/21190.101.0.1 to 190.101.7.254190.101.7.2552,046
162190.101.8.0/21190.101.8.1 to 190.101.15.254190.101.15.2552,046
163190.101.16.0/21190.101.16.1 to 190.101.23.254190.101.23.2552,046
164190.101.24.0/21190.101.24.1 to 190.101.31.254190.101.31.2552,046
165190.101.32.0/21190.101.32.1 to 190.101.39.254190.101.39.2552,046
166190.101.40.0/21190.101.40.1 to 190.101.47.254190.101.47.2552,046
167190.101.48.0/21190.101.48.1 to 190.101.55.254190.101.55.2552,046
168190.101.56.0/21190.101.56.1 to 190.101.63.254190.101.63.2552,046
169190.101.64.0/21190.101.64.1 to 190.101.71.254190.101.71.2552,046
170190.101.72.0/21190.101.72.1 to 190.101.79.254190.101.79.2552,046
171190.101.80.0/21190.101.80.1 to 190.101.87.254190.101.87.2552,046
172190.101.88.0/21190.101.88.1 to 190.101.95.254190.101.95.2552,046
173190.101.96.0/21190.101.96.1 to 190.101.103.254190.101.103.2552,046
174190.101.104.0/21190.101.104.1 to 190.101.111.254190.101.111.2552,046
175190.101.112.0/21190.101.112.1 to 190.101.119.254190.101.119.2552,046
176190.101.120.0/21190.101.120.1 to 190.101.127.254190.101.127.2552,046
177190.101.128.0/21190.101.128.1 to 190.101.135.254190.101.135.2552,046
178190.101.136.0/21190.101.136.1 to 190.101.143.254190.101.143.2552,046
179190.101.144.0/21190.101.144.1 to 190.101.151.254190.101.151.2552,046
180190.101.152.0/21190.101.152.1 to 190.101.159.254190.101.159.2552,046
181190.101.160.0/21190.101.160.1 to 190.101.167.254190.101.167.2552,046
182190.101.168.0/21190.101.168.1 to 190.101.175.254190.101.175.2552,046
183190.101.176.0/21190.101.176.1 to 190.101.183.254190.101.183.2552,046
184190.101.184.0/21190.101.184.1 to 190.101.191.254190.101.191.2552,046
185190.101.192.0/21190.101.192.1 to 190.101.199.254190.101.199.2552,046
186190.101.200.0/21190.101.200.1 to 190.101.207.254190.101.207.2552,046
187190.101.208.0/21190.101.208.1 to 190.101.215.254190.101.215.2552,046
188190.101.216.0/21190.101.216.1 to 190.101.223.254190.101.223.2552,046
189190.101.224.0/21190.101.224.1 to 190.101.231.254190.101.231.2552,046
190190.101.232.0/21190.101.232.1 to 190.101.239.254190.101.239.2552,046
191190.101.240.0/21190.101.240.1 to 190.101.247.254190.101.247.2552,046
192190.101.248.0/21190.101.248.1 to 190.101.255.254190.101.255.2552,046
193190.102.0.0/21190.102.0.1 to 190.102.7.254190.102.7.2552,046
194190.102.8.0/21190.102.8.1 to 190.102.15.254190.102.15.2552,046
195190.102.16.0/21190.102.16.1 to 190.102.23.254190.102.23.2552,046
196190.102.24.0/21190.102.24.1 to 190.102.31.254190.102.31.2552,046
197190.102.32.0/21190.102.32.1 to 190.102.39.254190.102.39.2552,046
198190.102.40.0/21190.102.40.1 to 190.102.47.254190.102.47.2552,046
199190.102.48.0/21190.102.48.1 to 190.102.55.254190.102.55.2552,046
200190.102.56.0/21190.102.56.1 to 190.102.63.254190.102.63.2552,046
201190.102.64.0/21190.102.64.1 to 190.102.71.254190.102.71.2552,046
202190.102.72.0/21190.102.72.1 to 190.102.79.254190.102.79.2552,046
203190.102.80.0/21190.102.80.1 to 190.102.87.254190.102.87.2552,046
204190.102.88.0/21190.102.88.1 to 190.102.95.254190.102.95.2552,046
205190.102.96.0/21190.102.96.1 to 190.102.103.254190.102.103.2552,046
206190.102.104.0/21190.102.104.1 to 190.102.111.254190.102.111.2552,046
207190.102.112.0/21190.102.112.1 to 190.102.119.254190.102.119.2552,046
208190.102.120.0/21190.102.120.1 to 190.102.127.254190.102.127.2552,046
209190.102.128.0/21190.102.128.1 to 190.102.135.254190.102.135.2552,046
210190.102.136.0/21190.102.136.1 to 190.102.143.254190.102.143.2552,046
211190.102.144.0/21190.102.144.1 to 190.102.151.254190.102.151.2552,046
212190.102.152.0/21190.102.152.1 to 190.102.159.254190.102.159.2552,046
213190.102.160.0/21190.102.160.1 to 190.102.167.254190.102.167.2552,046
214190.102.168.0/21190.102.168.1 to 190.102.175.254190.102.175.2552,046
215190.102.176.0/21190.102.176.1 to 190.102.183.254190.102.183.2552,046
216190.102.184.0/21190.102.184.1 to 190.102.191.254190.102.191.2552,046
217190.102.192.0/21190.102.192.1 to 190.102.199.254190.102.199.2552,046
218190.102.200.0/21190.102.200.1 to 190.102.207.254190.102.207.2552,046
219190.102.208.0/21190.102.208.1 to 190.102.215.254190.102.215.2552,046
220190.102.216.0/21190.102.216.1 to 190.102.223.254190.102.223.2552,046
221190.102.224.0/21190.102.224.1 to 190.102.231.254190.102.231.2552,046
222190.102.232.0/21190.102.232.1 to 190.102.239.254190.102.239.2552,046
223190.102.240.0/21190.102.240.1 to 190.102.247.254190.102.247.2552,046
224190.102.248.0/21190.102.248.1 to 190.102.255.254190.102.255.2552,046
225190.103.0.0/21190.103.0.1 to 190.103.7.254190.103.7.2552,046
226190.103.8.0/21190.103.8.1 to 190.103.15.254190.103.15.2552,046
227190.103.16.0/21190.103.16.1 to 190.103.23.254190.103.23.2552,046
228190.103.24.0/21190.103.24.1 to 190.103.31.254190.103.31.2552,046
229190.103.32.0/21190.103.32.1 to 190.103.39.254190.103.39.2552,046
230190.103.40.0/21190.103.40.1 to 190.103.47.254190.103.47.2552,046
231190.103.48.0/21190.103.48.1 to 190.103.55.254190.103.55.2552,046
232190.103.56.0/21190.103.56.1 to 190.103.63.254190.103.63.2552,046
233190.103.64.0/21190.103.64.1 to 190.103.71.254190.103.71.2552,046
234190.103.72.0/21190.103.72.1 to 190.103.79.254190.103.79.2552,046
235190.103.80.0/21190.103.80.1 to 190.103.87.254190.103.87.2552,046
236190.103.88.0/21190.103.88.1 to 190.103.95.254190.103.95.2552,046
237190.103.96.0/21190.103.96.1 to 190.103.103.254190.103.103.2552,046
238190.103.104.0/21190.103.104.1 to 190.103.111.254190.103.111.2552,046
239190.103.112.0/21190.103.112.1 to 190.103.119.254190.103.119.2552,046
240190.103.120.0/21190.103.120.1 to 190.103.127.254190.103.127.2552,046
241190.103.128.0/21190.103.128.1 to 190.103.135.254190.103.135.2552,046
242190.103.136.0/21190.103.136.1 to 190.103.143.254190.103.143.2552,046
243190.103.144.0/21190.103.144.1 to 190.103.151.254190.103.151.2552,046
244190.103.152.0/21190.103.152.1 to 190.103.159.254190.103.159.2552,046
245190.103.160.0/21190.103.160.1 to 190.103.167.254190.103.167.2552,046
246190.103.168.0/21190.103.168.1 to 190.103.175.254190.103.175.2552,046
247190.103.176.0/21190.103.176.1 to 190.103.183.254190.103.183.2552,046
248190.103.184.0/21190.103.184.1 to 190.103.191.254190.103.191.2552,046
249190.103.192.0/21190.103.192.1 to 190.103.199.254190.103.199.2552,046
250190.103.200.0/21190.103.200.1 to 190.103.207.254190.103.207.2552,046
251190.103.208.0/21190.103.208.1 to 190.103.215.254190.103.215.2552,046
252190.103.216.0/21190.103.216.1 to 190.103.223.254190.103.223.2552,046
253190.103.224.0/21190.103.224.1 to 190.103.231.254190.103.231.2552,046
254190.103.232.0/21190.103.232.1 to 190.103.239.254190.103.239.2552,046
255190.103.240.0/21190.103.240.1 to 190.103.247.254190.103.247.2552,046
256190.103.248.0/21190.103.248.1 to 190.103.255.254190.103.255.2552,046

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

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.