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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.

Network254.232.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
254.232.0.0
Broadcast address
254.235.255.255
First usable
254.232.0.1
Last usable
254.235.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Reserved 240.0.0.0/4
Future use; not usable on most systems
Old class
E (reserved)
As numbers
Hex FEE80000 · Integer 4276617216 to 4276879359
Reverse DNS zones
232.254.in-addr.arpa
233.254.in-addr.arpa
234.254.in-addr.arpa
235.254.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11111110.11101000.00000000.00000000254.232.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network11111110.11101000.00000000.00000000254.232.0.0
Broadcast11111110.11101011.11111111.11111111254.235.255.255
Split into smaller subnets/23
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

254.232.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1254.232.0.0/23254.232.0.1 to 254.232.1.254254.232.1.255510
2254.232.2.0/23254.232.2.1 to 254.232.3.254254.232.3.255510
3254.232.4.0/23254.232.4.1 to 254.232.5.254254.232.5.255510
4254.232.6.0/23254.232.6.1 to 254.232.7.254254.232.7.255510
5254.232.8.0/23254.232.8.1 to 254.232.9.254254.232.9.255510
6254.232.10.0/23254.232.10.1 to 254.232.11.254254.232.11.255510
7254.232.12.0/23254.232.12.1 to 254.232.13.254254.232.13.255510
8254.232.14.0/23254.232.14.1 to 254.232.15.254254.232.15.255510
9254.232.16.0/23254.232.16.1 to 254.232.17.254254.232.17.255510
10254.232.18.0/23254.232.18.1 to 254.232.19.254254.232.19.255510
11254.232.20.0/23254.232.20.1 to 254.232.21.254254.232.21.255510
12254.232.22.0/23254.232.22.1 to 254.232.23.254254.232.23.255510
13254.232.24.0/23254.232.24.1 to 254.232.25.254254.232.25.255510
14254.232.26.0/23254.232.26.1 to 254.232.27.254254.232.27.255510
15254.232.28.0/23254.232.28.1 to 254.232.29.254254.232.29.255510
16254.232.30.0/23254.232.30.1 to 254.232.31.254254.232.31.255510
17254.232.32.0/23254.232.32.1 to 254.232.33.254254.232.33.255510
18254.232.34.0/23254.232.34.1 to 254.232.35.254254.232.35.255510
19254.232.36.0/23254.232.36.1 to 254.232.37.254254.232.37.255510
20254.232.38.0/23254.232.38.1 to 254.232.39.254254.232.39.255510
21254.232.40.0/23254.232.40.1 to 254.232.41.254254.232.41.255510
22254.232.42.0/23254.232.42.1 to 254.232.43.254254.232.43.255510
23254.232.44.0/23254.232.44.1 to 254.232.45.254254.232.45.255510
24254.232.46.0/23254.232.46.1 to 254.232.47.254254.232.47.255510
25254.232.48.0/23254.232.48.1 to 254.232.49.254254.232.49.255510
26254.232.50.0/23254.232.50.1 to 254.232.51.254254.232.51.255510
27254.232.52.0/23254.232.52.1 to 254.232.53.254254.232.53.255510
28254.232.54.0/23254.232.54.1 to 254.232.55.254254.232.55.255510
29254.232.56.0/23254.232.56.1 to 254.232.57.254254.232.57.255510
30254.232.58.0/23254.232.58.1 to 254.232.59.254254.232.59.255510
31254.232.60.0/23254.232.60.1 to 254.232.61.254254.232.61.255510
32254.232.62.0/23254.232.62.1 to 254.232.63.254254.232.63.255510
33254.232.64.0/23254.232.64.1 to 254.232.65.254254.232.65.255510
34254.232.66.0/23254.232.66.1 to 254.232.67.254254.232.67.255510
35254.232.68.0/23254.232.68.1 to 254.232.69.254254.232.69.255510
36254.232.70.0/23254.232.70.1 to 254.232.71.254254.232.71.255510
37254.232.72.0/23254.232.72.1 to 254.232.73.254254.232.73.255510
38254.232.74.0/23254.232.74.1 to 254.232.75.254254.232.75.255510
39254.232.76.0/23254.232.76.1 to 254.232.77.254254.232.77.255510
40254.232.78.0/23254.232.78.1 to 254.232.79.254254.232.79.255510
41254.232.80.0/23254.232.80.1 to 254.232.81.254254.232.81.255510
42254.232.82.0/23254.232.82.1 to 254.232.83.254254.232.83.255510
43254.232.84.0/23254.232.84.1 to 254.232.85.254254.232.85.255510
44254.232.86.0/23254.232.86.1 to 254.232.87.254254.232.87.255510
45254.232.88.0/23254.232.88.1 to 254.232.89.254254.232.89.255510
46254.232.90.0/23254.232.90.1 to 254.232.91.254254.232.91.255510
47254.232.92.0/23254.232.92.1 to 254.232.93.254254.232.93.255510
48254.232.94.0/23254.232.94.1 to 254.232.95.254254.232.95.255510
49254.232.96.0/23254.232.96.1 to 254.232.97.254254.232.97.255510
50254.232.98.0/23254.232.98.1 to 254.232.99.254254.232.99.255510
51254.232.100.0/23254.232.100.1 to 254.232.101.254254.232.101.255510
52254.232.102.0/23254.232.102.1 to 254.232.103.254254.232.103.255510
53254.232.104.0/23254.232.104.1 to 254.232.105.254254.232.105.255510
54254.232.106.0/23254.232.106.1 to 254.232.107.254254.232.107.255510
55254.232.108.0/23254.232.108.1 to 254.232.109.254254.232.109.255510
56254.232.110.0/23254.232.110.1 to 254.232.111.254254.232.111.255510
57254.232.112.0/23254.232.112.1 to 254.232.113.254254.232.113.255510
58254.232.114.0/23254.232.114.1 to 254.232.115.254254.232.115.255510
59254.232.116.0/23254.232.116.1 to 254.232.117.254254.232.117.255510
60254.232.118.0/23254.232.118.1 to 254.232.119.254254.232.119.255510
61254.232.120.0/23254.232.120.1 to 254.232.121.254254.232.121.255510
62254.232.122.0/23254.232.122.1 to 254.232.123.254254.232.123.255510
63254.232.124.0/23254.232.124.1 to 254.232.125.254254.232.125.255510
64254.232.126.0/23254.232.126.1 to 254.232.127.254254.232.127.255510
65254.232.128.0/23254.232.128.1 to 254.232.129.254254.232.129.255510
66254.232.130.0/23254.232.130.1 to 254.232.131.254254.232.131.255510
67254.232.132.0/23254.232.132.1 to 254.232.133.254254.232.133.255510
68254.232.134.0/23254.232.134.1 to 254.232.135.254254.232.135.255510
69254.232.136.0/23254.232.136.1 to 254.232.137.254254.232.137.255510
70254.232.138.0/23254.232.138.1 to 254.232.139.254254.232.139.255510
71254.232.140.0/23254.232.140.1 to 254.232.141.254254.232.141.255510
72254.232.142.0/23254.232.142.1 to 254.232.143.254254.232.143.255510
73254.232.144.0/23254.232.144.1 to 254.232.145.254254.232.145.255510
74254.232.146.0/23254.232.146.1 to 254.232.147.254254.232.147.255510
75254.232.148.0/23254.232.148.1 to 254.232.149.254254.232.149.255510
76254.232.150.0/23254.232.150.1 to 254.232.151.254254.232.151.255510
77254.232.152.0/23254.232.152.1 to 254.232.153.254254.232.153.255510
78254.232.154.0/23254.232.154.1 to 254.232.155.254254.232.155.255510
79254.232.156.0/23254.232.156.1 to 254.232.157.254254.232.157.255510
80254.232.158.0/23254.232.158.1 to 254.232.159.254254.232.159.255510
81254.232.160.0/23254.232.160.1 to 254.232.161.254254.232.161.255510
82254.232.162.0/23254.232.162.1 to 254.232.163.254254.232.163.255510
83254.232.164.0/23254.232.164.1 to 254.232.165.254254.232.165.255510
84254.232.166.0/23254.232.166.1 to 254.232.167.254254.232.167.255510
85254.232.168.0/23254.232.168.1 to 254.232.169.254254.232.169.255510
86254.232.170.0/23254.232.170.1 to 254.232.171.254254.232.171.255510
87254.232.172.0/23254.232.172.1 to 254.232.173.254254.232.173.255510
88254.232.174.0/23254.232.174.1 to 254.232.175.254254.232.175.255510
89254.232.176.0/23254.232.176.1 to 254.232.177.254254.232.177.255510
90254.232.178.0/23254.232.178.1 to 254.232.179.254254.232.179.255510
91254.232.180.0/23254.232.180.1 to 254.232.181.254254.232.181.255510
92254.232.182.0/23254.232.182.1 to 254.232.183.254254.232.183.255510
93254.232.184.0/23254.232.184.1 to 254.232.185.254254.232.185.255510
94254.232.186.0/23254.232.186.1 to 254.232.187.254254.232.187.255510
95254.232.188.0/23254.232.188.1 to 254.232.189.254254.232.189.255510
96254.232.190.0/23254.232.190.1 to 254.232.191.254254.232.191.255510
97254.232.192.0/23254.232.192.1 to 254.232.193.254254.232.193.255510
98254.232.194.0/23254.232.194.1 to 254.232.195.254254.232.195.255510
99254.232.196.0/23254.232.196.1 to 254.232.197.254254.232.197.255510
100254.232.198.0/23254.232.198.1 to 254.232.199.254254.232.199.255510
101254.232.200.0/23254.232.200.1 to 254.232.201.254254.232.201.255510
102254.232.202.0/23254.232.202.1 to 254.232.203.254254.232.203.255510
103254.232.204.0/23254.232.204.1 to 254.232.205.254254.232.205.255510
104254.232.206.0/23254.232.206.1 to 254.232.207.254254.232.207.255510
105254.232.208.0/23254.232.208.1 to 254.232.209.254254.232.209.255510
106254.232.210.0/23254.232.210.1 to 254.232.211.254254.232.211.255510
107254.232.212.0/23254.232.212.1 to 254.232.213.254254.232.213.255510
108254.232.214.0/23254.232.214.1 to 254.232.215.254254.232.215.255510
109254.232.216.0/23254.232.216.1 to 254.232.217.254254.232.217.255510
110254.232.218.0/23254.232.218.1 to 254.232.219.254254.232.219.255510
111254.232.220.0/23254.232.220.1 to 254.232.221.254254.232.221.255510
112254.232.222.0/23254.232.222.1 to 254.232.223.254254.232.223.255510
113254.232.224.0/23254.232.224.1 to 254.232.225.254254.232.225.255510
114254.232.226.0/23254.232.226.1 to 254.232.227.254254.232.227.255510
115254.232.228.0/23254.232.228.1 to 254.232.229.254254.232.229.255510
116254.232.230.0/23254.232.230.1 to 254.232.231.254254.232.231.255510
117254.232.232.0/23254.232.232.1 to 254.232.233.254254.232.233.255510
118254.232.234.0/23254.232.234.1 to 254.232.235.254254.232.235.255510
119254.232.236.0/23254.232.236.1 to 254.232.237.254254.232.237.255510
120254.232.238.0/23254.232.238.1 to 254.232.239.254254.232.239.255510
121254.232.240.0/23254.232.240.1 to 254.232.241.254254.232.241.255510
122254.232.242.0/23254.232.242.1 to 254.232.243.254254.232.243.255510
123254.232.244.0/23254.232.244.1 to 254.232.245.254254.232.245.255510
124254.232.246.0/23254.232.246.1 to 254.232.247.254254.232.247.255510
125254.232.248.0/23254.232.248.1 to 254.232.249.254254.232.249.255510
126254.232.250.0/23254.232.250.1 to 254.232.251.254254.232.251.255510
127254.232.252.0/23254.232.252.1 to 254.232.253.254254.232.253.255510
128254.232.254.0/23254.232.254.1 to 254.232.255.254254.232.255.255510
129254.233.0.0/23254.233.0.1 to 254.233.1.254254.233.1.255510
130254.233.2.0/23254.233.2.1 to 254.233.3.254254.233.3.255510
131254.233.4.0/23254.233.4.1 to 254.233.5.254254.233.5.255510
132254.233.6.0/23254.233.6.1 to 254.233.7.254254.233.7.255510
133254.233.8.0/23254.233.8.1 to 254.233.9.254254.233.9.255510
134254.233.10.0/23254.233.10.1 to 254.233.11.254254.233.11.255510
135254.233.12.0/23254.233.12.1 to 254.233.13.254254.233.13.255510
136254.233.14.0/23254.233.14.1 to 254.233.15.254254.233.15.255510
137254.233.16.0/23254.233.16.1 to 254.233.17.254254.233.17.255510
138254.233.18.0/23254.233.18.1 to 254.233.19.254254.233.19.255510
139254.233.20.0/23254.233.20.1 to 254.233.21.254254.233.21.255510
140254.233.22.0/23254.233.22.1 to 254.233.23.254254.233.23.255510
141254.233.24.0/23254.233.24.1 to 254.233.25.254254.233.25.255510
142254.233.26.0/23254.233.26.1 to 254.233.27.254254.233.27.255510
143254.233.28.0/23254.233.28.1 to 254.233.29.254254.233.29.255510
144254.233.30.0/23254.233.30.1 to 254.233.31.254254.233.31.255510
145254.233.32.0/23254.233.32.1 to 254.233.33.254254.233.33.255510
146254.233.34.0/23254.233.34.1 to 254.233.35.254254.233.35.255510
147254.233.36.0/23254.233.36.1 to 254.233.37.254254.233.37.255510
148254.233.38.0/23254.233.38.1 to 254.233.39.254254.233.39.255510
149254.233.40.0/23254.233.40.1 to 254.233.41.254254.233.41.255510
150254.233.42.0/23254.233.42.1 to 254.233.43.254254.233.43.255510
151254.233.44.0/23254.233.44.1 to 254.233.45.254254.233.45.255510
152254.233.46.0/23254.233.46.1 to 254.233.47.254254.233.47.255510
153254.233.48.0/23254.233.48.1 to 254.233.49.254254.233.49.255510
154254.233.50.0/23254.233.50.1 to 254.233.51.254254.233.51.255510
155254.233.52.0/23254.233.52.1 to 254.233.53.254254.233.53.255510
156254.233.54.0/23254.233.54.1 to 254.233.55.254254.233.55.255510
157254.233.56.0/23254.233.56.1 to 254.233.57.254254.233.57.255510
158254.233.58.0/23254.233.58.1 to 254.233.59.254254.233.59.255510
159254.233.60.0/23254.233.60.1 to 254.233.61.254254.233.61.255510
160254.233.62.0/23254.233.62.1 to 254.233.63.254254.233.63.255510
161254.233.64.0/23254.233.64.1 to 254.233.65.254254.233.65.255510
162254.233.66.0/23254.233.66.1 to 254.233.67.254254.233.67.255510
163254.233.68.0/23254.233.68.1 to 254.233.69.254254.233.69.255510
164254.233.70.0/23254.233.70.1 to 254.233.71.254254.233.71.255510
165254.233.72.0/23254.233.72.1 to 254.233.73.254254.233.73.255510
166254.233.74.0/23254.233.74.1 to 254.233.75.254254.233.75.255510
167254.233.76.0/23254.233.76.1 to 254.233.77.254254.233.77.255510
168254.233.78.0/23254.233.78.1 to 254.233.79.254254.233.79.255510
169254.233.80.0/23254.233.80.1 to 254.233.81.254254.233.81.255510
170254.233.82.0/23254.233.82.1 to 254.233.83.254254.233.83.255510
171254.233.84.0/23254.233.84.1 to 254.233.85.254254.233.85.255510
172254.233.86.0/23254.233.86.1 to 254.233.87.254254.233.87.255510
173254.233.88.0/23254.233.88.1 to 254.233.89.254254.233.89.255510
174254.233.90.0/23254.233.90.1 to 254.233.91.254254.233.91.255510
175254.233.92.0/23254.233.92.1 to 254.233.93.254254.233.93.255510
176254.233.94.0/23254.233.94.1 to 254.233.95.254254.233.95.255510
177254.233.96.0/23254.233.96.1 to 254.233.97.254254.233.97.255510
178254.233.98.0/23254.233.98.1 to 254.233.99.254254.233.99.255510
179254.233.100.0/23254.233.100.1 to 254.233.101.254254.233.101.255510
180254.233.102.0/23254.233.102.1 to 254.233.103.254254.233.103.255510
181254.233.104.0/23254.233.104.1 to 254.233.105.254254.233.105.255510
182254.233.106.0/23254.233.106.1 to 254.233.107.254254.233.107.255510
183254.233.108.0/23254.233.108.1 to 254.233.109.254254.233.109.255510
184254.233.110.0/23254.233.110.1 to 254.233.111.254254.233.111.255510
185254.233.112.0/23254.233.112.1 to 254.233.113.254254.233.113.255510
186254.233.114.0/23254.233.114.1 to 254.233.115.254254.233.115.255510
187254.233.116.0/23254.233.116.1 to 254.233.117.254254.233.117.255510
188254.233.118.0/23254.233.118.1 to 254.233.119.254254.233.119.255510
189254.233.120.0/23254.233.120.1 to 254.233.121.254254.233.121.255510
190254.233.122.0/23254.233.122.1 to 254.233.123.254254.233.123.255510
191254.233.124.0/23254.233.124.1 to 254.233.125.254254.233.125.255510
192254.233.126.0/23254.233.126.1 to 254.233.127.254254.233.127.255510
193254.233.128.0/23254.233.128.1 to 254.233.129.254254.233.129.255510
194254.233.130.0/23254.233.130.1 to 254.233.131.254254.233.131.255510
195254.233.132.0/23254.233.132.1 to 254.233.133.254254.233.133.255510
196254.233.134.0/23254.233.134.1 to 254.233.135.254254.233.135.255510
197254.233.136.0/23254.233.136.1 to 254.233.137.254254.233.137.255510
198254.233.138.0/23254.233.138.1 to 254.233.139.254254.233.139.255510
199254.233.140.0/23254.233.140.1 to 254.233.141.254254.233.141.255510
200254.233.142.0/23254.233.142.1 to 254.233.143.254254.233.143.255510
201254.233.144.0/23254.233.144.1 to 254.233.145.254254.233.145.255510
202254.233.146.0/23254.233.146.1 to 254.233.147.254254.233.147.255510
203254.233.148.0/23254.233.148.1 to 254.233.149.254254.233.149.255510
204254.233.150.0/23254.233.150.1 to 254.233.151.254254.233.151.255510
205254.233.152.0/23254.233.152.1 to 254.233.153.254254.233.153.255510
206254.233.154.0/23254.233.154.1 to 254.233.155.254254.233.155.255510
207254.233.156.0/23254.233.156.1 to 254.233.157.254254.233.157.255510
208254.233.158.0/23254.233.158.1 to 254.233.159.254254.233.159.255510
209254.233.160.0/23254.233.160.1 to 254.233.161.254254.233.161.255510
210254.233.162.0/23254.233.162.1 to 254.233.163.254254.233.163.255510
211254.233.164.0/23254.233.164.1 to 254.233.165.254254.233.165.255510
212254.233.166.0/23254.233.166.1 to 254.233.167.254254.233.167.255510
213254.233.168.0/23254.233.168.1 to 254.233.169.254254.233.169.255510
214254.233.170.0/23254.233.170.1 to 254.233.171.254254.233.171.255510
215254.233.172.0/23254.233.172.1 to 254.233.173.254254.233.173.255510
216254.233.174.0/23254.233.174.1 to 254.233.175.254254.233.175.255510
217254.233.176.0/23254.233.176.1 to 254.233.177.254254.233.177.255510
218254.233.178.0/23254.233.178.1 to 254.233.179.254254.233.179.255510
219254.233.180.0/23254.233.180.1 to 254.233.181.254254.233.181.255510
220254.233.182.0/23254.233.182.1 to 254.233.183.254254.233.183.255510
221254.233.184.0/23254.233.184.1 to 254.233.185.254254.233.185.255510
222254.233.186.0/23254.233.186.1 to 254.233.187.254254.233.187.255510
223254.233.188.0/23254.233.188.1 to 254.233.189.254254.233.189.255510
224254.233.190.0/23254.233.190.1 to 254.233.191.254254.233.191.255510
225254.233.192.0/23254.233.192.1 to 254.233.193.254254.233.193.255510
226254.233.194.0/23254.233.194.1 to 254.233.195.254254.233.195.255510
227254.233.196.0/23254.233.196.1 to 254.233.197.254254.233.197.255510
228254.233.198.0/23254.233.198.1 to 254.233.199.254254.233.199.255510
229254.233.200.0/23254.233.200.1 to 254.233.201.254254.233.201.255510
230254.233.202.0/23254.233.202.1 to 254.233.203.254254.233.203.255510
231254.233.204.0/23254.233.204.1 to 254.233.205.254254.233.205.255510
232254.233.206.0/23254.233.206.1 to 254.233.207.254254.233.207.255510
233254.233.208.0/23254.233.208.1 to 254.233.209.254254.233.209.255510
234254.233.210.0/23254.233.210.1 to 254.233.211.254254.233.211.255510
235254.233.212.0/23254.233.212.1 to 254.233.213.254254.233.213.255510
236254.233.214.0/23254.233.214.1 to 254.233.215.254254.233.215.255510
237254.233.216.0/23254.233.216.1 to 254.233.217.254254.233.217.255510
238254.233.218.0/23254.233.218.1 to 254.233.219.254254.233.219.255510
239254.233.220.0/23254.233.220.1 to 254.233.221.254254.233.221.255510
240254.233.222.0/23254.233.222.1 to 254.233.223.254254.233.223.255510
241254.233.224.0/23254.233.224.1 to 254.233.225.254254.233.225.255510
242254.233.226.0/23254.233.226.1 to 254.233.227.254254.233.227.255510
243254.233.228.0/23254.233.228.1 to 254.233.229.254254.233.229.255510
244254.233.230.0/23254.233.230.1 to 254.233.231.254254.233.231.255510
245254.233.232.0/23254.233.232.1 to 254.233.233.254254.233.233.255510
246254.233.234.0/23254.233.234.1 to 254.233.235.254254.233.235.255510
247254.233.236.0/23254.233.236.1 to 254.233.237.254254.233.237.255510
248254.233.238.0/23254.233.238.1 to 254.233.239.254254.233.239.255510
249254.233.240.0/23254.233.240.1 to 254.233.241.254254.233.241.255510
250254.233.242.0/23254.233.242.1 to 254.233.243.254254.233.243.255510
251254.233.244.0/23254.233.244.1 to 254.233.245.254254.233.245.255510
252254.233.246.0/23254.233.246.1 to 254.233.247.254254.233.247.255510
253254.233.248.0/23254.233.248.1 to 254.233.249.254254.233.249.255510
254254.233.250.0/23254.233.250.1 to 254.233.251.254254.233.251.255510
255254.233.252.0/23254.233.252.1 to 254.233.253.254254.233.253.255510
256254.233.254.0/23254.233.254.1 to 254.233.255.254254.233.255.255510

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.