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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.

Network234.32.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
234.32.0.0
Broadcast address
234.63.255.255
First usable
234.32.0.1
Last usable
234.63.255.254
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
Multicast 224.0.0.0/4
One-to-many traffic, such as IPTV and routing protocols
Old class
D (multicast)
As numbers
Hex EA200000 · Integer 3927965696 to 3930062847
Reverse DNS zones
32.234.in-addr.arpa
33.234.in-addr.arpa
34.234.in-addr.arpa
35.234.in-addr.arpa
36.234.in-addr.arpa
37.234.in-addr.arpa
38.234.in-addr.arpa
39.234.in-addr.arpa
40.234.in-addr.arpa
41.234.in-addr.arpa
42.234.in-addr.arpa
43.234.in-addr.arpa
44.234.in-addr.arpa
45.234.in-addr.arpa
46.234.in-addr.arpa
47.234.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
Address11101010.00100000.00000000.00000000234.32.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11101010.00100000.00000000.00000000234.32.0.0
Broadcast11101010.00111111.11111111.11111111234.63.255.255
Split into smaller subnets/23
/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)

234.32.0.0/11 makes 4,096 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1234.32.0.0/23234.32.0.1 to 234.32.1.254234.32.1.255510
2234.32.2.0/23234.32.2.1 to 234.32.3.254234.32.3.255510
3234.32.4.0/23234.32.4.1 to 234.32.5.254234.32.5.255510
4234.32.6.0/23234.32.6.1 to 234.32.7.254234.32.7.255510
5234.32.8.0/23234.32.8.1 to 234.32.9.254234.32.9.255510
6234.32.10.0/23234.32.10.1 to 234.32.11.254234.32.11.255510
7234.32.12.0/23234.32.12.1 to 234.32.13.254234.32.13.255510
8234.32.14.0/23234.32.14.1 to 234.32.15.254234.32.15.255510
9234.32.16.0/23234.32.16.1 to 234.32.17.254234.32.17.255510
10234.32.18.0/23234.32.18.1 to 234.32.19.254234.32.19.255510
11234.32.20.0/23234.32.20.1 to 234.32.21.254234.32.21.255510
12234.32.22.0/23234.32.22.1 to 234.32.23.254234.32.23.255510
13234.32.24.0/23234.32.24.1 to 234.32.25.254234.32.25.255510
14234.32.26.0/23234.32.26.1 to 234.32.27.254234.32.27.255510
15234.32.28.0/23234.32.28.1 to 234.32.29.254234.32.29.255510
16234.32.30.0/23234.32.30.1 to 234.32.31.254234.32.31.255510
17234.32.32.0/23234.32.32.1 to 234.32.33.254234.32.33.255510
18234.32.34.0/23234.32.34.1 to 234.32.35.254234.32.35.255510
19234.32.36.0/23234.32.36.1 to 234.32.37.254234.32.37.255510
20234.32.38.0/23234.32.38.1 to 234.32.39.254234.32.39.255510
21234.32.40.0/23234.32.40.1 to 234.32.41.254234.32.41.255510
22234.32.42.0/23234.32.42.1 to 234.32.43.254234.32.43.255510
23234.32.44.0/23234.32.44.1 to 234.32.45.254234.32.45.255510
24234.32.46.0/23234.32.46.1 to 234.32.47.254234.32.47.255510
25234.32.48.0/23234.32.48.1 to 234.32.49.254234.32.49.255510
26234.32.50.0/23234.32.50.1 to 234.32.51.254234.32.51.255510
27234.32.52.0/23234.32.52.1 to 234.32.53.254234.32.53.255510
28234.32.54.0/23234.32.54.1 to 234.32.55.254234.32.55.255510
29234.32.56.0/23234.32.56.1 to 234.32.57.254234.32.57.255510
30234.32.58.0/23234.32.58.1 to 234.32.59.254234.32.59.255510
31234.32.60.0/23234.32.60.1 to 234.32.61.254234.32.61.255510
32234.32.62.0/23234.32.62.1 to 234.32.63.254234.32.63.255510
33234.32.64.0/23234.32.64.1 to 234.32.65.254234.32.65.255510
34234.32.66.0/23234.32.66.1 to 234.32.67.254234.32.67.255510
35234.32.68.0/23234.32.68.1 to 234.32.69.254234.32.69.255510
36234.32.70.0/23234.32.70.1 to 234.32.71.254234.32.71.255510
37234.32.72.0/23234.32.72.1 to 234.32.73.254234.32.73.255510
38234.32.74.0/23234.32.74.1 to 234.32.75.254234.32.75.255510
39234.32.76.0/23234.32.76.1 to 234.32.77.254234.32.77.255510
40234.32.78.0/23234.32.78.1 to 234.32.79.254234.32.79.255510
41234.32.80.0/23234.32.80.1 to 234.32.81.254234.32.81.255510
42234.32.82.0/23234.32.82.1 to 234.32.83.254234.32.83.255510
43234.32.84.0/23234.32.84.1 to 234.32.85.254234.32.85.255510
44234.32.86.0/23234.32.86.1 to 234.32.87.254234.32.87.255510
45234.32.88.0/23234.32.88.1 to 234.32.89.254234.32.89.255510
46234.32.90.0/23234.32.90.1 to 234.32.91.254234.32.91.255510
47234.32.92.0/23234.32.92.1 to 234.32.93.254234.32.93.255510
48234.32.94.0/23234.32.94.1 to 234.32.95.254234.32.95.255510
49234.32.96.0/23234.32.96.1 to 234.32.97.254234.32.97.255510
50234.32.98.0/23234.32.98.1 to 234.32.99.254234.32.99.255510
51234.32.100.0/23234.32.100.1 to 234.32.101.254234.32.101.255510
52234.32.102.0/23234.32.102.1 to 234.32.103.254234.32.103.255510
53234.32.104.0/23234.32.104.1 to 234.32.105.254234.32.105.255510
54234.32.106.0/23234.32.106.1 to 234.32.107.254234.32.107.255510
55234.32.108.0/23234.32.108.1 to 234.32.109.254234.32.109.255510
56234.32.110.0/23234.32.110.1 to 234.32.111.254234.32.111.255510
57234.32.112.0/23234.32.112.1 to 234.32.113.254234.32.113.255510
58234.32.114.0/23234.32.114.1 to 234.32.115.254234.32.115.255510
59234.32.116.0/23234.32.116.1 to 234.32.117.254234.32.117.255510
60234.32.118.0/23234.32.118.1 to 234.32.119.254234.32.119.255510
61234.32.120.0/23234.32.120.1 to 234.32.121.254234.32.121.255510
62234.32.122.0/23234.32.122.1 to 234.32.123.254234.32.123.255510
63234.32.124.0/23234.32.124.1 to 234.32.125.254234.32.125.255510
64234.32.126.0/23234.32.126.1 to 234.32.127.254234.32.127.255510
65234.32.128.0/23234.32.128.1 to 234.32.129.254234.32.129.255510
66234.32.130.0/23234.32.130.1 to 234.32.131.254234.32.131.255510
67234.32.132.0/23234.32.132.1 to 234.32.133.254234.32.133.255510
68234.32.134.0/23234.32.134.1 to 234.32.135.254234.32.135.255510
69234.32.136.0/23234.32.136.1 to 234.32.137.254234.32.137.255510
70234.32.138.0/23234.32.138.1 to 234.32.139.254234.32.139.255510
71234.32.140.0/23234.32.140.1 to 234.32.141.254234.32.141.255510
72234.32.142.0/23234.32.142.1 to 234.32.143.254234.32.143.255510
73234.32.144.0/23234.32.144.1 to 234.32.145.254234.32.145.255510
74234.32.146.0/23234.32.146.1 to 234.32.147.254234.32.147.255510
75234.32.148.0/23234.32.148.1 to 234.32.149.254234.32.149.255510
76234.32.150.0/23234.32.150.1 to 234.32.151.254234.32.151.255510
77234.32.152.0/23234.32.152.1 to 234.32.153.254234.32.153.255510
78234.32.154.0/23234.32.154.1 to 234.32.155.254234.32.155.255510
79234.32.156.0/23234.32.156.1 to 234.32.157.254234.32.157.255510
80234.32.158.0/23234.32.158.1 to 234.32.159.254234.32.159.255510
81234.32.160.0/23234.32.160.1 to 234.32.161.254234.32.161.255510
82234.32.162.0/23234.32.162.1 to 234.32.163.254234.32.163.255510
83234.32.164.0/23234.32.164.1 to 234.32.165.254234.32.165.255510
84234.32.166.0/23234.32.166.1 to 234.32.167.254234.32.167.255510
85234.32.168.0/23234.32.168.1 to 234.32.169.254234.32.169.255510
86234.32.170.0/23234.32.170.1 to 234.32.171.254234.32.171.255510
87234.32.172.0/23234.32.172.1 to 234.32.173.254234.32.173.255510
88234.32.174.0/23234.32.174.1 to 234.32.175.254234.32.175.255510
89234.32.176.0/23234.32.176.1 to 234.32.177.254234.32.177.255510
90234.32.178.0/23234.32.178.1 to 234.32.179.254234.32.179.255510
91234.32.180.0/23234.32.180.1 to 234.32.181.254234.32.181.255510
92234.32.182.0/23234.32.182.1 to 234.32.183.254234.32.183.255510
93234.32.184.0/23234.32.184.1 to 234.32.185.254234.32.185.255510
94234.32.186.0/23234.32.186.1 to 234.32.187.254234.32.187.255510
95234.32.188.0/23234.32.188.1 to 234.32.189.254234.32.189.255510
96234.32.190.0/23234.32.190.1 to 234.32.191.254234.32.191.255510
97234.32.192.0/23234.32.192.1 to 234.32.193.254234.32.193.255510
98234.32.194.0/23234.32.194.1 to 234.32.195.254234.32.195.255510
99234.32.196.0/23234.32.196.1 to 234.32.197.254234.32.197.255510
100234.32.198.0/23234.32.198.1 to 234.32.199.254234.32.199.255510
101234.32.200.0/23234.32.200.1 to 234.32.201.254234.32.201.255510
102234.32.202.0/23234.32.202.1 to 234.32.203.254234.32.203.255510
103234.32.204.0/23234.32.204.1 to 234.32.205.254234.32.205.255510
104234.32.206.0/23234.32.206.1 to 234.32.207.254234.32.207.255510
105234.32.208.0/23234.32.208.1 to 234.32.209.254234.32.209.255510
106234.32.210.0/23234.32.210.1 to 234.32.211.254234.32.211.255510
107234.32.212.0/23234.32.212.1 to 234.32.213.254234.32.213.255510
108234.32.214.0/23234.32.214.1 to 234.32.215.254234.32.215.255510
109234.32.216.0/23234.32.216.1 to 234.32.217.254234.32.217.255510
110234.32.218.0/23234.32.218.1 to 234.32.219.254234.32.219.255510
111234.32.220.0/23234.32.220.1 to 234.32.221.254234.32.221.255510
112234.32.222.0/23234.32.222.1 to 234.32.223.254234.32.223.255510
113234.32.224.0/23234.32.224.1 to 234.32.225.254234.32.225.255510
114234.32.226.0/23234.32.226.1 to 234.32.227.254234.32.227.255510
115234.32.228.0/23234.32.228.1 to 234.32.229.254234.32.229.255510
116234.32.230.0/23234.32.230.1 to 234.32.231.254234.32.231.255510
117234.32.232.0/23234.32.232.1 to 234.32.233.254234.32.233.255510
118234.32.234.0/23234.32.234.1 to 234.32.235.254234.32.235.255510
119234.32.236.0/23234.32.236.1 to 234.32.237.254234.32.237.255510
120234.32.238.0/23234.32.238.1 to 234.32.239.254234.32.239.255510
121234.32.240.0/23234.32.240.1 to 234.32.241.254234.32.241.255510
122234.32.242.0/23234.32.242.1 to 234.32.243.254234.32.243.255510
123234.32.244.0/23234.32.244.1 to 234.32.245.254234.32.245.255510
124234.32.246.0/23234.32.246.1 to 234.32.247.254234.32.247.255510
125234.32.248.0/23234.32.248.1 to 234.32.249.254234.32.249.255510
126234.32.250.0/23234.32.250.1 to 234.32.251.254234.32.251.255510
127234.32.252.0/23234.32.252.1 to 234.32.253.254234.32.253.255510
128234.32.254.0/23234.32.254.1 to 234.32.255.254234.32.255.255510
129234.33.0.0/23234.33.0.1 to 234.33.1.254234.33.1.255510
130234.33.2.0/23234.33.2.1 to 234.33.3.254234.33.3.255510
131234.33.4.0/23234.33.4.1 to 234.33.5.254234.33.5.255510
132234.33.6.0/23234.33.6.1 to 234.33.7.254234.33.7.255510
133234.33.8.0/23234.33.8.1 to 234.33.9.254234.33.9.255510
134234.33.10.0/23234.33.10.1 to 234.33.11.254234.33.11.255510
135234.33.12.0/23234.33.12.1 to 234.33.13.254234.33.13.255510
136234.33.14.0/23234.33.14.1 to 234.33.15.254234.33.15.255510
137234.33.16.0/23234.33.16.1 to 234.33.17.254234.33.17.255510
138234.33.18.0/23234.33.18.1 to 234.33.19.254234.33.19.255510
139234.33.20.0/23234.33.20.1 to 234.33.21.254234.33.21.255510
140234.33.22.0/23234.33.22.1 to 234.33.23.254234.33.23.255510
141234.33.24.0/23234.33.24.1 to 234.33.25.254234.33.25.255510
142234.33.26.0/23234.33.26.1 to 234.33.27.254234.33.27.255510
143234.33.28.0/23234.33.28.1 to 234.33.29.254234.33.29.255510
144234.33.30.0/23234.33.30.1 to 234.33.31.254234.33.31.255510
145234.33.32.0/23234.33.32.1 to 234.33.33.254234.33.33.255510
146234.33.34.0/23234.33.34.1 to 234.33.35.254234.33.35.255510
147234.33.36.0/23234.33.36.1 to 234.33.37.254234.33.37.255510
148234.33.38.0/23234.33.38.1 to 234.33.39.254234.33.39.255510
149234.33.40.0/23234.33.40.1 to 234.33.41.254234.33.41.255510
150234.33.42.0/23234.33.42.1 to 234.33.43.254234.33.43.255510
151234.33.44.0/23234.33.44.1 to 234.33.45.254234.33.45.255510
152234.33.46.0/23234.33.46.1 to 234.33.47.254234.33.47.255510
153234.33.48.0/23234.33.48.1 to 234.33.49.254234.33.49.255510
154234.33.50.0/23234.33.50.1 to 234.33.51.254234.33.51.255510
155234.33.52.0/23234.33.52.1 to 234.33.53.254234.33.53.255510
156234.33.54.0/23234.33.54.1 to 234.33.55.254234.33.55.255510
157234.33.56.0/23234.33.56.1 to 234.33.57.254234.33.57.255510
158234.33.58.0/23234.33.58.1 to 234.33.59.254234.33.59.255510
159234.33.60.0/23234.33.60.1 to 234.33.61.254234.33.61.255510
160234.33.62.0/23234.33.62.1 to 234.33.63.254234.33.63.255510
161234.33.64.0/23234.33.64.1 to 234.33.65.254234.33.65.255510
162234.33.66.0/23234.33.66.1 to 234.33.67.254234.33.67.255510
163234.33.68.0/23234.33.68.1 to 234.33.69.254234.33.69.255510
164234.33.70.0/23234.33.70.1 to 234.33.71.254234.33.71.255510
165234.33.72.0/23234.33.72.1 to 234.33.73.254234.33.73.255510
166234.33.74.0/23234.33.74.1 to 234.33.75.254234.33.75.255510
167234.33.76.0/23234.33.76.1 to 234.33.77.254234.33.77.255510
168234.33.78.0/23234.33.78.1 to 234.33.79.254234.33.79.255510
169234.33.80.0/23234.33.80.1 to 234.33.81.254234.33.81.255510
170234.33.82.0/23234.33.82.1 to 234.33.83.254234.33.83.255510
171234.33.84.0/23234.33.84.1 to 234.33.85.254234.33.85.255510
172234.33.86.0/23234.33.86.1 to 234.33.87.254234.33.87.255510
173234.33.88.0/23234.33.88.1 to 234.33.89.254234.33.89.255510
174234.33.90.0/23234.33.90.1 to 234.33.91.254234.33.91.255510
175234.33.92.0/23234.33.92.1 to 234.33.93.254234.33.93.255510
176234.33.94.0/23234.33.94.1 to 234.33.95.254234.33.95.255510
177234.33.96.0/23234.33.96.1 to 234.33.97.254234.33.97.255510
178234.33.98.0/23234.33.98.1 to 234.33.99.254234.33.99.255510
179234.33.100.0/23234.33.100.1 to 234.33.101.254234.33.101.255510
180234.33.102.0/23234.33.102.1 to 234.33.103.254234.33.103.255510
181234.33.104.0/23234.33.104.1 to 234.33.105.254234.33.105.255510
182234.33.106.0/23234.33.106.1 to 234.33.107.254234.33.107.255510
183234.33.108.0/23234.33.108.1 to 234.33.109.254234.33.109.255510
184234.33.110.0/23234.33.110.1 to 234.33.111.254234.33.111.255510
185234.33.112.0/23234.33.112.1 to 234.33.113.254234.33.113.255510
186234.33.114.0/23234.33.114.1 to 234.33.115.254234.33.115.255510
187234.33.116.0/23234.33.116.1 to 234.33.117.254234.33.117.255510
188234.33.118.0/23234.33.118.1 to 234.33.119.254234.33.119.255510
189234.33.120.0/23234.33.120.1 to 234.33.121.254234.33.121.255510
190234.33.122.0/23234.33.122.1 to 234.33.123.254234.33.123.255510
191234.33.124.0/23234.33.124.1 to 234.33.125.254234.33.125.255510
192234.33.126.0/23234.33.126.1 to 234.33.127.254234.33.127.255510
193234.33.128.0/23234.33.128.1 to 234.33.129.254234.33.129.255510
194234.33.130.0/23234.33.130.1 to 234.33.131.254234.33.131.255510
195234.33.132.0/23234.33.132.1 to 234.33.133.254234.33.133.255510
196234.33.134.0/23234.33.134.1 to 234.33.135.254234.33.135.255510
197234.33.136.0/23234.33.136.1 to 234.33.137.254234.33.137.255510
198234.33.138.0/23234.33.138.1 to 234.33.139.254234.33.139.255510
199234.33.140.0/23234.33.140.1 to 234.33.141.254234.33.141.255510
200234.33.142.0/23234.33.142.1 to 234.33.143.254234.33.143.255510
201234.33.144.0/23234.33.144.1 to 234.33.145.254234.33.145.255510
202234.33.146.0/23234.33.146.1 to 234.33.147.254234.33.147.255510
203234.33.148.0/23234.33.148.1 to 234.33.149.254234.33.149.255510
204234.33.150.0/23234.33.150.1 to 234.33.151.254234.33.151.255510
205234.33.152.0/23234.33.152.1 to 234.33.153.254234.33.153.255510
206234.33.154.0/23234.33.154.1 to 234.33.155.254234.33.155.255510
207234.33.156.0/23234.33.156.1 to 234.33.157.254234.33.157.255510
208234.33.158.0/23234.33.158.1 to 234.33.159.254234.33.159.255510
209234.33.160.0/23234.33.160.1 to 234.33.161.254234.33.161.255510
210234.33.162.0/23234.33.162.1 to 234.33.163.254234.33.163.255510
211234.33.164.0/23234.33.164.1 to 234.33.165.254234.33.165.255510
212234.33.166.0/23234.33.166.1 to 234.33.167.254234.33.167.255510
213234.33.168.0/23234.33.168.1 to 234.33.169.254234.33.169.255510
214234.33.170.0/23234.33.170.1 to 234.33.171.254234.33.171.255510
215234.33.172.0/23234.33.172.1 to 234.33.173.254234.33.173.255510
216234.33.174.0/23234.33.174.1 to 234.33.175.254234.33.175.255510
217234.33.176.0/23234.33.176.1 to 234.33.177.254234.33.177.255510
218234.33.178.0/23234.33.178.1 to 234.33.179.254234.33.179.255510
219234.33.180.0/23234.33.180.1 to 234.33.181.254234.33.181.255510
220234.33.182.0/23234.33.182.1 to 234.33.183.254234.33.183.255510
221234.33.184.0/23234.33.184.1 to 234.33.185.254234.33.185.255510
222234.33.186.0/23234.33.186.1 to 234.33.187.254234.33.187.255510
223234.33.188.0/23234.33.188.1 to 234.33.189.254234.33.189.255510
224234.33.190.0/23234.33.190.1 to 234.33.191.254234.33.191.255510
225234.33.192.0/23234.33.192.1 to 234.33.193.254234.33.193.255510
226234.33.194.0/23234.33.194.1 to 234.33.195.254234.33.195.255510
227234.33.196.0/23234.33.196.1 to 234.33.197.254234.33.197.255510
228234.33.198.0/23234.33.198.1 to 234.33.199.254234.33.199.255510
229234.33.200.0/23234.33.200.1 to 234.33.201.254234.33.201.255510
230234.33.202.0/23234.33.202.1 to 234.33.203.254234.33.203.255510
231234.33.204.0/23234.33.204.1 to 234.33.205.254234.33.205.255510
232234.33.206.0/23234.33.206.1 to 234.33.207.254234.33.207.255510
233234.33.208.0/23234.33.208.1 to 234.33.209.254234.33.209.255510
234234.33.210.0/23234.33.210.1 to 234.33.211.254234.33.211.255510
235234.33.212.0/23234.33.212.1 to 234.33.213.254234.33.213.255510
236234.33.214.0/23234.33.214.1 to 234.33.215.254234.33.215.255510
237234.33.216.0/23234.33.216.1 to 234.33.217.254234.33.217.255510
238234.33.218.0/23234.33.218.1 to 234.33.219.254234.33.219.255510
239234.33.220.0/23234.33.220.1 to 234.33.221.254234.33.221.255510
240234.33.222.0/23234.33.222.1 to 234.33.223.254234.33.223.255510
241234.33.224.0/23234.33.224.1 to 234.33.225.254234.33.225.255510
242234.33.226.0/23234.33.226.1 to 234.33.227.254234.33.227.255510
243234.33.228.0/23234.33.228.1 to 234.33.229.254234.33.229.255510
244234.33.230.0/23234.33.230.1 to 234.33.231.254234.33.231.255510
245234.33.232.0/23234.33.232.1 to 234.33.233.254234.33.233.255510
246234.33.234.0/23234.33.234.1 to 234.33.235.254234.33.235.255510
247234.33.236.0/23234.33.236.1 to 234.33.237.254234.33.237.255510
248234.33.238.0/23234.33.238.1 to 234.33.239.254234.33.239.255510
249234.33.240.0/23234.33.240.1 to 234.33.241.254234.33.241.255510
250234.33.242.0/23234.33.242.1 to 234.33.243.254234.33.243.255510
251234.33.244.0/23234.33.244.1 to 234.33.245.254234.33.245.255510
252234.33.246.0/23234.33.246.1 to 234.33.247.254234.33.247.255510
253234.33.248.0/23234.33.248.1 to 234.33.249.254234.33.249.255510
254234.33.250.0/23234.33.250.1 to 234.33.251.254234.33.251.255510
255234.33.252.0/23234.33.252.1 to 234.33.253.254234.33.253.255510
256234.33.254.0/23234.33.254.1 to 234.33.255.254234.33.255.255510

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.