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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.

Network232.0.0.0/5
Usable hosts134,217,726
Subnet mask248.0.0.0
Addresses134,217,728
Network address
232.0.0.0
Broadcast address
239.255.255.255
First usable
232.0.0.1
Last usable
239.255.255.254
Usable hosts
134,217,726 (134,217,728 less the network and broadcast addresses)
Subnet mask
248.0.0.0
Wildcard mask
7.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/5
Type
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex E8000000 · Integer 3892314112 to 4026531839
Reverse DNS zones
232.in-addr.arpa
233.in-addr.arpa
234.in-addr.arpa
235.in-addr.arpa
236.in-addr.arpa
237.in-addr.arpa
238.in-addr.arpa
239.in-addr.arpa
/5 is not on a 8-bit boundary, so it takes 8 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11101000.00000000.00000000.00000000232.0.0.0
Subnet mask11111000.00000000.00000000.00000000248.0.0.0
Network11101000.00000000.00000000.00000000232.0.0.0
Broadcast11101111.11111111.11111111.11111111239.255.255.255
Split into smaller subnets/14
/6 (2)/7 (4)/8 (8)/9 (16)/10 (32)/11 (64)/12 (128)/13 (256)/14 (512)/15 (1,024)/16 (2,048)/17 (4,096)

232.0.0.0/5 makes 512 subnets of /14; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1232.0.0.0/14232.0.0.1 to 232.3.255.254232.3.255.255262,142
2232.4.0.0/14232.4.0.1 to 232.7.255.254232.7.255.255262,142
3232.8.0.0/14232.8.0.1 to 232.11.255.254232.11.255.255262,142
4232.12.0.0/14232.12.0.1 to 232.15.255.254232.15.255.255262,142
5232.16.0.0/14232.16.0.1 to 232.19.255.254232.19.255.255262,142
6232.20.0.0/14232.20.0.1 to 232.23.255.254232.23.255.255262,142
7232.24.0.0/14232.24.0.1 to 232.27.255.254232.27.255.255262,142
8232.28.0.0/14232.28.0.1 to 232.31.255.254232.31.255.255262,142
9232.32.0.0/14232.32.0.1 to 232.35.255.254232.35.255.255262,142
10232.36.0.0/14232.36.0.1 to 232.39.255.254232.39.255.255262,142
11232.40.0.0/14232.40.0.1 to 232.43.255.254232.43.255.255262,142
12232.44.0.0/14232.44.0.1 to 232.47.255.254232.47.255.255262,142
13232.48.0.0/14232.48.0.1 to 232.51.255.254232.51.255.255262,142
14232.52.0.0/14232.52.0.1 to 232.55.255.254232.55.255.255262,142
15232.56.0.0/14232.56.0.1 to 232.59.255.254232.59.255.255262,142
16232.60.0.0/14232.60.0.1 to 232.63.255.254232.63.255.255262,142
17232.64.0.0/14232.64.0.1 to 232.67.255.254232.67.255.255262,142
18232.68.0.0/14232.68.0.1 to 232.71.255.254232.71.255.255262,142
19232.72.0.0/14232.72.0.1 to 232.75.255.254232.75.255.255262,142
20232.76.0.0/14232.76.0.1 to 232.79.255.254232.79.255.255262,142
21232.80.0.0/14232.80.0.1 to 232.83.255.254232.83.255.255262,142
22232.84.0.0/14232.84.0.1 to 232.87.255.254232.87.255.255262,142
23232.88.0.0/14232.88.0.1 to 232.91.255.254232.91.255.255262,142
24232.92.0.0/14232.92.0.1 to 232.95.255.254232.95.255.255262,142
25232.96.0.0/14232.96.0.1 to 232.99.255.254232.99.255.255262,142
26232.100.0.0/14232.100.0.1 to 232.103.255.254232.103.255.255262,142
27232.104.0.0/14232.104.0.1 to 232.107.255.254232.107.255.255262,142
28232.108.0.0/14232.108.0.1 to 232.111.255.254232.111.255.255262,142
29232.112.0.0/14232.112.0.1 to 232.115.255.254232.115.255.255262,142
30232.116.0.0/14232.116.0.1 to 232.119.255.254232.119.255.255262,142
31232.120.0.0/14232.120.0.1 to 232.123.255.254232.123.255.255262,142
32232.124.0.0/14232.124.0.1 to 232.127.255.254232.127.255.255262,142
33232.128.0.0/14232.128.0.1 to 232.131.255.254232.131.255.255262,142
34232.132.0.0/14232.132.0.1 to 232.135.255.254232.135.255.255262,142
35232.136.0.0/14232.136.0.1 to 232.139.255.254232.139.255.255262,142
36232.140.0.0/14232.140.0.1 to 232.143.255.254232.143.255.255262,142
37232.144.0.0/14232.144.0.1 to 232.147.255.254232.147.255.255262,142
38232.148.0.0/14232.148.0.1 to 232.151.255.254232.151.255.255262,142
39232.152.0.0/14232.152.0.1 to 232.155.255.254232.155.255.255262,142
40232.156.0.0/14232.156.0.1 to 232.159.255.254232.159.255.255262,142
41232.160.0.0/14232.160.0.1 to 232.163.255.254232.163.255.255262,142
42232.164.0.0/14232.164.0.1 to 232.167.255.254232.167.255.255262,142
43232.168.0.0/14232.168.0.1 to 232.171.255.254232.171.255.255262,142
44232.172.0.0/14232.172.0.1 to 232.175.255.254232.175.255.255262,142
45232.176.0.0/14232.176.0.1 to 232.179.255.254232.179.255.255262,142
46232.180.0.0/14232.180.0.1 to 232.183.255.254232.183.255.255262,142
47232.184.0.0/14232.184.0.1 to 232.187.255.254232.187.255.255262,142
48232.188.0.0/14232.188.0.1 to 232.191.255.254232.191.255.255262,142
49232.192.0.0/14232.192.0.1 to 232.195.255.254232.195.255.255262,142
50232.196.0.0/14232.196.0.1 to 232.199.255.254232.199.255.255262,142
51232.200.0.0/14232.200.0.1 to 232.203.255.254232.203.255.255262,142
52232.204.0.0/14232.204.0.1 to 232.207.255.254232.207.255.255262,142
53232.208.0.0/14232.208.0.1 to 232.211.255.254232.211.255.255262,142
54232.212.0.0/14232.212.0.1 to 232.215.255.254232.215.255.255262,142
55232.216.0.0/14232.216.0.1 to 232.219.255.254232.219.255.255262,142
56232.220.0.0/14232.220.0.1 to 232.223.255.254232.223.255.255262,142
57232.224.0.0/14232.224.0.1 to 232.227.255.254232.227.255.255262,142
58232.228.0.0/14232.228.0.1 to 232.231.255.254232.231.255.255262,142
59232.232.0.0/14232.232.0.1 to 232.235.255.254232.235.255.255262,142
60232.236.0.0/14232.236.0.1 to 232.239.255.254232.239.255.255262,142
61232.240.0.0/14232.240.0.1 to 232.243.255.254232.243.255.255262,142
62232.244.0.0/14232.244.0.1 to 232.247.255.254232.247.255.255262,142
63232.248.0.0/14232.248.0.1 to 232.251.255.254232.251.255.255262,142
64232.252.0.0/14232.252.0.1 to 232.255.255.254232.255.255.255262,142
65233.0.0.0/14233.0.0.1 to 233.3.255.254233.3.255.255262,142
66233.4.0.0/14233.4.0.1 to 233.7.255.254233.7.255.255262,142
67233.8.0.0/14233.8.0.1 to 233.11.255.254233.11.255.255262,142
68233.12.0.0/14233.12.0.1 to 233.15.255.254233.15.255.255262,142
69233.16.0.0/14233.16.0.1 to 233.19.255.254233.19.255.255262,142
70233.20.0.0/14233.20.0.1 to 233.23.255.254233.23.255.255262,142
71233.24.0.0/14233.24.0.1 to 233.27.255.254233.27.255.255262,142
72233.28.0.0/14233.28.0.1 to 233.31.255.254233.31.255.255262,142
73233.32.0.0/14233.32.0.1 to 233.35.255.254233.35.255.255262,142
74233.36.0.0/14233.36.0.1 to 233.39.255.254233.39.255.255262,142
75233.40.0.0/14233.40.0.1 to 233.43.255.254233.43.255.255262,142
76233.44.0.0/14233.44.0.1 to 233.47.255.254233.47.255.255262,142
77233.48.0.0/14233.48.0.1 to 233.51.255.254233.51.255.255262,142
78233.52.0.0/14233.52.0.1 to 233.55.255.254233.55.255.255262,142
79233.56.0.0/14233.56.0.1 to 233.59.255.254233.59.255.255262,142
80233.60.0.0/14233.60.0.1 to 233.63.255.254233.63.255.255262,142
81233.64.0.0/14233.64.0.1 to 233.67.255.254233.67.255.255262,142
82233.68.0.0/14233.68.0.1 to 233.71.255.254233.71.255.255262,142
83233.72.0.0/14233.72.0.1 to 233.75.255.254233.75.255.255262,142
84233.76.0.0/14233.76.0.1 to 233.79.255.254233.79.255.255262,142
85233.80.0.0/14233.80.0.1 to 233.83.255.254233.83.255.255262,142
86233.84.0.0/14233.84.0.1 to 233.87.255.254233.87.255.255262,142
87233.88.0.0/14233.88.0.1 to 233.91.255.254233.91.255.255262,142
88233.92.0.0/14233.92.0.1 to 233.95.255.254233.95.255.255262,142
89233.96.0.0/14233.96.0.1 to 233.99.255.254233.99.255.255262,142
90233.100.0.0/14233.100.0.1 to 233.103.255.254233.103.255.255262,142
91233.104.0.0/14233.104.0.1 to 233.107.255.254233.107.255.255262,142
92233.108.0.0/14233.108.0.1 to 233.111.255.254233.111.255.255262,142
93233.112.0.0/14233.112.0.1 to 233.115.255.254233.115.255.255262,142
94233.116.0.0/14233.116.0.1 to 233.119.255.254233.119.255.255262,142
95233.120.0.0/14233.120.0.1 to 233.123.255.254233.123.255.255262,142
96233.124.0.0/14233.124.0.1 to 233.127.255.254233.127.255.255262,142
97233.128.0.0/14233.128.0.1 to 233.131.255.254233.131.255.255262,142
98233.132.0.0/14233.132.0.1 to 233.135.255.254233.135.255.255262,142
99233.136.0.0/14233.136.0.1 to 233.139.255.254233.139.255.255262,142
100233.140.0.0/14233.140.0.1 to 233.143.255.254233.143.255.255262,142
101233.144.0.0/14233.144.0.1 to 233.147.255.254233.147.255.255262,142
102233.148.0.0/14233.148.0.1 to 233.151.255.254233.151.255.255262,142
103233.152.0.0/14233.152.0.1 to 233.155.255.254233.155.255.255262,142
104233.156.0.0/14233.156.0.1 to 233.159.255.254233.159.255.255262,142
105233.160.0.0/14233.160.0.1 to 233.163.255.254233.163.255.255262,142
106233.164.0.0/14233.164.0.1 to 233.167.255.254233.167.255.255262,142
107233.168.0.0/14233.168.0.1 to 233.171.255.254233.171.255.255262,142
108233.172.0.0/14233.172.0.1 to 233.175.255.254233.175.255.255262,142
109233.176.0.0/14233.176.0.1 to 233.179.255.254233.179.255.255262,142
110233.180.0.0/14233.180.0.1 to 233.183.255.254233.183.255.255262,142
111233.184.0.0/14233.184.0.1 to 233.187.255.254233.187.255.255262,142
112233.188.0.0/14233.188.0.1 to 233.191.255.254233.191.255.255262,142
113233.192.0.0/14233.192.0.1 to 233.195.255.254233.195.255.255262,142
114233.196.0.0/14233.196.0.1 to 233.199.255.254233.199.255.255262,142
115233.200.0.0/14233.200.0.1 to 233.203.255.254233.203.255.255262,142
116233.204.0.0/14233.204.0.1 to 233.207.255.254233.207.255.255262,142
117233.208.0.0/14233.208.0.1 to 233.211.255.254233.211.255.255262,142
118233.212.0.0/14233.212.0.1 to 233.215.255.254233.215.255.255262,142
119233.216.0.0/14233.216.0.1 to 233.219.255.254233.219.255.255262,142
120233.220.0.0/14233.220.0.1 to 233.223.255.254233.223.255.255262,142
121233.224.0.0/14233.224.0.1 to 233.227.255.254233.227.255.255262,142
122233.228.0.0/14233.228.0.1 to 233.231.255.254233.231.255.255262,142
123233.232.0.0/14233.232.0.1 to 233.235.255.254233.235.255.255262,142
124233.236.0.0/14233.236.0.1 to 233.239.255.254233.239.255.255262,142
125233.240.0.0/14233.240.0.1 to 233.243.255.254233.243.255.255262,142
126233.244.0.0/14233.244.0.1 to 233.247.255.254233.247.255.255262,142
127233.248.0.0/14233.248.0.1 to 233.251.255.254233.251.255.255262,142
128233.252.0.0/14233.252.0.1 to 233.255.255.254233.255.255.255262,142
129234.0.0.0/14234.0.0.1 to 234.3.255.254234.3.255.255262,142
130234.4.0.0/14234.4.0.1 to 234.7.255.254234.7.255.255262,142
131234.8.0.0/14234.8.0.1 to 234.11.255.254234.11.255.255262,142
132234.12.0.0/14234.12.0.1 to 234.15.255.254234.15.255.255262,142
133234.16.0.0/14234.16.0.1 to 234.19.255.254234.19.255.255262,142
134234.20.0.0/14234.20.0.1 to 234.23.255.254234.23.255.255262,142
135234.24.0.0/14234.24.0.1 to 234.27.255.254234.27.255.255262,142
136234.28.0.0/14234.28.0.1 to 234.31.255.254234.31.255.255262,142
137234.32.0.0/14234.32.0.1 to 234.35.255.254234.35.255.255262,142
138234.36.0.0/14234.36.0.1 to 234.39.255.254234.39.255.255262,142
139234.40.0.0/14234.40.0.1 to 234.43.255.254234.43.255.255262,142
140234.44.0.0/14234.44.0.1 to 234.47.255.254234.47.255.255262,142
141234.48.0.0/14234.48.0.1 to 234.51.255.254234.51.255.255262,142
142234.52.0.0/14234.52.0.1 to 234.55.255.254234.55.255.255262,142
143234.56.0.0/14234.56.0.1 to 234.59.255.254234.59.255.255262,142
144234.60.0.0/14234.60.0.1 to 234.63.255.254234.63.255.255262,142
145234.64.0.0/14234.64.0.1 to 234.67.255.254234.67.255.255262,142
146234.68.0.0/14234.68.0.1 to 234.71.255.254234.71.255.255262,142
147234.72.0.0/14234.72.0.1 to 234.75.255.254234.75.255.255262,142
148234.76.0.0/14234.76.0.1 to 234.79.255.254234.79.255.255262,142
149234.80.0.0/14234.80.0.1 to 234.83.255.254234.83.255.255262,142
150234.84.0.0/14234.84.0.1 to 234.87.255.254234.87.255.255262,142
151234.88.0.0/14234.88.0.1 to 234.91.255.254234.91.255.255262,142
152234.92.0.0/14234.92.0.1 to 234.95.255.254234.95.255.255262,142
153234.96.0.0/14234.96.0.1 to 234.99.255.254234.99.255.255262,142
154234.100.0.0/14234.100.0.1 to 234.103.255.254234.103.255.255262,142
155234.104.0.0/14234.104.0.1 to 234.107.255.254234.107.255.255262,142
156234.108.0.0/14234.108.0.1 to 234.111.255.254234.111.255.255262,142
157234.112.0.0/14234.112.0.1 to 234.115.255.254234.115.255.255262,142
158234.116.0.0/14234.116.0.1 to 234.119.255.254234.119.255.255262,142
159234.120.0.0/14234.120.0.1 to 234.123.255.254234.123.255.255262,142
160234.124.0.0/14234.124.0.1 to 234.127.255.254234.127.255.255262,142
161234.128.0.0/14234.128.0.1 to 234.131.255.254234.131.255.255262,142
162234.132.0.0/14234.132.0.1 to 234.135.255.254234.135.255.255262,142
163234.136.0.0/14234.136.0.1 to 234.139.255.254234.139.255.255262,142
164234.140.0.0/14234.140.0.1 to 234.143.255.254234.143.255.255262,142
165234.144.0.0/14234.144.0.1 to 234.147.255.254234.147.255.255262,142
166234.148.0.0/14234.148.0.1 to 234.151.255.254234.151.255.255262,142
167234.152.0.0/14234.152.0.1 to 234.155.255.254234.155.255.255262,142
168234.156.0.0/14234.156.0.1 to 234.159.255.254234.159.255.255262,142
169234.160.0.0/14234.160.0.1 to 234.163.255.254234.163.255.255262,142
170234.164.0.0/14234.164.0.1 to 234.167.255.254234.167.255.255262,142
171234.168.0.0/14234.168.0.1 to 234.171.255.254234.171.255.255262,142
172234.172.0.0/14234.172.0.1 to 234.175.255.254234.175.255.255262,142
173234.176.0.0/14234.176.0.1 to 234.179.255.254234.179.255.255262,142
174234.180.0.0/14234.180.0.1 to 234.183.255.254234.183.255.255262,142
175234.184.0.0/14234.184.0.1 to 234.187.255.254234.187.255.255262,142
176234.188.0.0/14234.188.0.1 to 234.191.255.254234.191.255.255262,142
177234.192.0.0/14234.192.0.1 to 234.195.255.254234.195.255.255262,142
178234.196.0.0/14234.196.0.1 to 234.199.255.254234.199.255.255262,142
179234.200.0.0/14234.200.0.1 to 234.203.255.254234.203.255.255262,142
180234.204.0.0/14234.204.0.1 to 234.207.255.254234.207.255.255262,142
181234.208.0.0/14234.208.0.1 to 234.211.255.254234.211.255.255262,142
182234.212.0.0/14234.212.0.1 to 234.215.255.254234.215.255.255262,142
183234.216.0.0/14234.216.0.1 to 234.219.255.254234.219.255.255262,142
184234.220.0.0/14234.220.0.1 to 234.223.255.254234.223.255.255262,142
185234.224.0.0/14234.224.0.1 to 234.227.255.254234.227.255.255262,142
186234.228.0.0/14234.228.0.1 to 234.231.255.254234.231.255.255262,142
187234.232.0.0/14234.232.0.1 to 234.235.255.254234.235.255.255262,142
188234.236.0.0/14234.236.0.1 to 234.239.255.254234.239.255.255262,142
189234.240.0.0/14234.240.0.1 to 234.243.255.254234.243.255.255262,142
190234.244.0.0/14234.244.0.1 to 234.247.255.254234.247.255.255262,142
191234.248.0.0/14234.248.0.1 to 234.251.255.254234.251.255.255262,142
192234.252.0.0/14234.252.0.1 to 234.255.255.254234.255.255.255262,142
193235.0.0.0/14235.0.0.1 to 235.3.255.254235.3.255.255262,142
194235.4.0.0/14235.4.0.1 to 235.7.255.254235.7.255.255262,142
195235.8.0.0/14235.8.0.1 to 235.11.255.254235.11.255.255262,142
196235.12.0.0/14235.12.0.1 to 235.15.255.254235.15.255.255262,142
197235.16.0.0/14235.16.0.1 to 235.19.255.254235.19.255.255262,142
198235.20.0.0/14235.20.0.1 to 235.23.255.254235.23.255.255262,142
199235.24.0.0/14235.24.0.1 to 235.27.255.254235.27.255.255262,142
200235.28.0.0/14235.28.0.1 to 235.31.255.254235.31.255.255262,142
201235.32.0.0/14235.32.0.1 to 235.35.255.254235.35.255.255262,142
202235.36.0.0/14235.36.0.1 to 235.39.255.254235.39.255.255262,142
203235.40.0.0/14235.40.0.1 to 235.43.255.254235.43.255.255262,142
204235.44.0.0/14235.44.0.1 to 235.47.255.254235.47.255.255262,142
205235.48.0.0/14235.48.0.1 to 235.51.255.254235.51.255.255262,142
206235.52.0.0/14235.52.0.1 to 235.55.255.254235.55.255.255262,142
207235.56.0.0/14235.56.0.1 to 235.59.255.254235.59.255.255262,142
208235.60.0.0/14235.60.0.1 to 235.63.255.254235.63.255.255262,142
209235.64.0.0/14235.64.0.1 to 235.67.255.254235.67.255.255262,142
210235.68.0.0/14235.68.0.1 to 235.71.255.254235.71.255.255262,142
211235.72.0.0/14235.72.0.1 to 235.75.255.254235.75.255.255262,142
212235.76.0.0/14235.76.0.1 to 235.79.255.254235.79.255.255262,142
213235.80.0.0/14235.80.0.1 to 235.83.255.254235.83.255.255262,142
214235.84.0.0/14235.84.0.1 to 235.87.255.254235.87.255.255262,142
215235.88.0.0/14235.88.0.1 to 235.91.255.254235.91.255.255262,142
216235.92.0.0/14235.92.0.1 to 235.95.255.254235.95.255.255262,142
217235.96.0.0/14235.96.0.1 to 235.99.255.254235.99.255.255262,142
218235.100.0.0/14235.100.0.1 to 235.103.255.254235.103.255.255262,142
219235.104.0.0/14235.104.0.1 to 235.107.255.254235.107.255.255262,142
220235.108.0.0/14235.108.0.1 to 235.111.255.254235.111.255.255262,142
221235.112.0.0/14235.112.0.1 to 235.115.255.254235.115.255.255262,142
222235.116.0.0/14235.116.0.1 to 235.119.255.254235.119.255.255262,142
223235.120.0.0/14235.120.0.1 to 235.123.255.254235.123.255.255262,142
224235.124.0.0/14235.124.0.1 to 235.127.255.254235.127.255.255262,142
225235.128.0.0/14235.128.0.1 to 235.131.255.254235.131.255.255262,142
226235.132.0.0/14235.132.0.1 to 235.135.255.254235.135.255.255262,142
227235.136.0.0/14235.136.0.1 to 235.139.255.254235.139.255.255262,142
228235.140.0.0/14235.140.0.1 to 235.143.255.254235.143.255.255262,142
229235.144.0.0/14235.144.0.1 to 235.147.255.254235.147.255.255262,142
230235.148.0.0/14235.148.0.1 to 235.151.255.254235.151.255.255262,142
231235.152.0.0/14235.152.0.1 to 235.155.255.254235.155.255.255262,142
232235.156.0.0/14235.156.0.1 to 235.159.255.254235.159.255.255262,142
233235.160.0.0/14235.160.0.1 to 235.163.255.254235.163.255.255262,142
234235.164.0.0/14235.164.0.1 to 235.167.255.254235.167.255.255262,142
235235.168.0.0/14235.168.0.1 to 235.171.255.254235.171.255.255262,142
236235.172.0.0/14235.172.0.1 to 235.175.255.254235.175.255.255262,142
237235.176.0.0/14235.176.0.1 to 235.179.255.254235.179.255.255262,142
238235.180.0.0/14235.180.0.1 to 235.183.255.254235.183.255.255262,142
239235.184.0.0/14235.184.0.1 to 235.187.255.254235.187.255.255262,142
240235.188.0.0/14235.188.0.1 to 235.191.255.254235.191.255.255262,142
241235.192.0.0/14235.192.0.1 to 235.195.255.254235.195.255.255262,142
242235.196.0.0/14235.196.0.1 to 235.199.255.254235.199.255.255262,142
243235.200.0.0/14235.200.0.1 to 235.203.255.254235.203.255.255262,142
244235.204.0.0/14235.204.0.1 to 235.207.255.254235.207.255.255262,142
245235.208.0.0/14235.208.0.1 to 235.211.255.254235.211.255.255262,142
246235.212.0.0/14235.212.0.1 to 235.215.255.254235.215.255.255262,142
247235.216.0.0/14235.216.0.1 to 235.219.255.254235.219.255.255262,142
248235.220.0.0/14235.220.0.1 to 235.223.255.254235.223.255.255262,142
249235.224.0.0/14235.224.0.1 to 235.227.255.254235.227.255.255262,142
250235.228.0.0/14235.228.0.1 to 235.231.255.254235.231.255.255262,142
251235.232.0.0/14235.232.0.1 to 235.235.255.254235.235.255.255262,142
252235.236.0.0/14235.236.0.1 to 235.239.255.254235.239.255.255262,142
253235.240.0.0/14235.240.0.1 to 235.243.255.254235.243.255.255262,142
254235.244.0.0/14235.244.0.1 to 235.247.255.254235.247.255.255262,142
255235.248.0.0/14235.248.0.1 to 235.251.255.254235.251.255.255262,142
256235.252.0.0/14235.252.0.1 to 235.255.255.254235.255.255.255262,142

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.