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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.

Network110.232.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
110.232.0.0
Broadcast address
110.233.255.255
First usable
110.232.0.1
Last usable
110.233.255.254
Usable hosts
131,070 (131,072 less the network and broadcast addresses)
Subnet mask
255.254.0.0
Wildcard mask
0.1.255.255 (Cisco ACLs, OSPF)
Prefix length
/15
Type
Public public
Old class
A (default /8)
As numbers
Hex 6EE80000 · Integer 1860698112 to 1860829183
Reverse DNS zones
232.110.in-addr.arpa
233.110.in-addr.arpa
/15 is not on a 8-bit boundary, so it takes 2 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01101110.11101000.00000000.00000000110.232.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network01101110.11101000.00000000.00000000110.232.0.0
Broadcast01101110.11101001.11111111.11111111110.233.255.255
Split into smaller subnets/24
/16 (2)/17 (4)/18 (8)/19 (16)/20 (32)/21 (64)/22 (128)/23 (256)/24 (512)/25 (1,024)/26 (2,048)/27 (4,096)

110.232.0.0/15 makes 512 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1110.232.0.0/24110.232.0.1 to 110.232.0.254110.232.0.255254
2110.232.1.0/24110.232.1.1 to 110.232.1.254110.232.1.255254
3110.232.2.0/24110.232.2.1 to 110.232.2.254110.232.2.255254
4110.232.3.0/24110.232.3.1 to 110.232.3.254110.232.3.255254
5110.232.4.0/24110.232.4.1 to 110.232.4.254110.232.4.255254
6110.232.5.0/24110.232.5.1 to 110.232.5.254110.232.5.255254
7110.232.6.0/24110.232.6.1 to 110.232.6.254110.232.6.255254
8110.232.7.0/24110.232.7.1 to 110.232.7.254110.232.7.255254
9110.232.8.0/24110.232.8.1 to 110.232.8.254110.232.8.255254
10110.232.9.0/24110.232.9.1 to 110.232.9.254110.232.9.255254
11110.232.10.0/24110.232.10.1 to 110.232.10.254110.232.10.255254
12110.232.11.0/24110.232.11.1 to 110.232.11.254110.232.11.255254
13110.232.12.0/24110.232.12.1 to 110.232.12.254110.232.12.255254
14110.232.13.0/24110.232.13.1 to 110.232.13.254110.232.13.255254
15110.232.14.0/24110.232.14.1 to 110.232.14.254110.232.14.255254
16110.232.15.0/24110.232.15.1 to 110.232.15.254110.232.15.255254
17110.232.16.0/24110.232.16.1 to 110.232.16.254110.232.16.255254
18110.232.17.0/24110.232.17.1 to 110.232.17.254110.232.17.255254
19110.232.18.0/24110.232.18.1 to 110.232.18.254110.232.18.255254
20110.232.19.0/24110.232.19.1 to 110.232.19.254110.232.19.255254
21110.232.20.0/24110.232.20.1 to 110.232.20.254110.232.20.255254
22110.232.21.0/24110.232.21.1 to 110.232.21.254110.232.21.255254
23110.232.22.0/24110.232.22.1 to 110.232.22.254110.232.22.255254
24110.232.23.0/24110.232.23.1 to 110.232.23.254110.232.23.255254
25110.232.24.0/24110.232.24.1 to 110.232.24.254110.232.24.255254
26110.232.25.0/24110.232.25.1 to 110.232.25.254110.232.25.255254
27110.232.26.0/24110.232.26.1 to 110.232.26.254110.232.26.255254
28110.232.27.0/24110.232.27.1 to 110.232.27.254110.232.27.255254
29110.232.28.0/24110.232.28.1 to 110.232.28.254110.232.28.255254
30110.232.29.0/24110.232.29.1 to 110.232.29.254110.232.29.255254
31110.232.30.0/24110.232.30.1 to 110.232.30.254110.232.30.255254
32110.232.31.0/24110.232.31.1 to 110.232.31.254110.232.31.255254
33110.232.32.0/24110.232.32.1 to 110.232.32.254110.232.32.255254
34110.232.33.0/24110.232.33.1 to 110.232.33.254110.232.33.255254
35110.232.34.0/24110.232.34.1 to 110.232.34.254110.232.34.255254
36110.232.35.0/24110.232.35.1 to 110.232.35.254110.232.35.255254
37110.232.36.0/24110.232.36.1 to 110.232.36.254110.232.36.255254
38110.232.37.0/24110.232.37.1 to 110.232.37.254110.232.37.255254
39110.232.38.0/24110.232.38.1 to 110.232.38.254110.232.38.255254
40110.232.39.0/24110.232.39.1 to 110.232.39.254110.232.39.255254
41110.232.40.0/24110.232.40.1 to 110.232.40.254110.232.40.255254
42110.232.41.0/24110.232.41.1 to 110.232.41.254110.232.41.255254
43110.232.42.0/24110.232.42.1 to 110.232.42.254110.232.42.255254
44110.232.43.0/24110.232.43.1 to 110.232.43.254110.232.43.255254
45110.232.44.0/24110.232.44.1 to 110.232.44.254110.232.44.255254
46110.232.45.0/24110.232.45.1 to 110.232.45.254110.232.45.255254
47110.232.46.0/24110.232.46.1 to 110.232.46.254110.232.46.255254
48110.232.47.0/24110.232.47.1 to 110.232.47.254110.232.47.255254
49110.232.48.0/24110.232.48.1 to 110.232.48.254110.232.48.255254
50110.232.49.0/24110.232.49.1 to 110.232.49.254110.232.49.255254
51110.232.50.0/24110.232.50.1 to 110.232.50.254110.232.50.255254
52110.232.51.0/24110.232.51.1 to 110.232.51.254110.232.51.255254
53110.232.52.0/24110.232.52.1 to 110.232.52.254110.232.52.255254
54110.232.53.0/24110.232.53.1 to 110.232.53.254110.232.53.255254
55110.232.54.0/24110.232.54.1 to 110.232.54.254110.232.54.255254
56110.232.55.0/24110.232.55.1 to 110.232.55.254110.232.55.255254
57110.232.56.0/24110.232.56.1 to 110.232.56.254110.232.56.255254
58110.232.57.0/24110.232.57.1 to 110.232.57.254110.232.57.255254
59110.232.58.0/24110.232.58.1 to 110.232.58.254110.232.58.255254
60110.232.59.0/24110.232.59.1 to 110.232.59.254110.232.59.255254
61110.232.60.0/24110.232.60.1 to 110.232.60.254110.232.60.255254
62110.232.61.0/24110.232.61.1 to 110.232.61.254110.232.61.255254
63110.232.62.0/24110.232.62.1 to 110.232.62.254110.232.62.255254
64110.232.63.0/24110.232.63.1 to 110.232.63.254110.232.63.255254
65110.232.64.0/24110.232.64.1 to 110.232.64.254110.232.64.255254
66110.232.65.0/24110.232.65.1 to 110.232.65.254110.232.65.255254
67110.232.66.0/24110.232.66.1 to 110.232.66.254110.232.66.255254
68110.232.67.0/24110.232.67.1 to 110.232.67.254110.232.67.255254
69110.232.68.0/24110.232.68.1 to 110.232.68.254110.232.68.255254
70110.232.69.0/24110.232.69.1 to 110.232.69.254110.232.69.255254
71110.232.70.0/24110.232.70.1 to 110.232.70.254110.232.70.255254
72110.232.71.0/24110.232.71.1 to 110.232.71.254110.232.71.255254
73110.232.72.0/24110.232.72.1 to 110.232.72.254110.232.72.255254
74110.232.73.0/24110.232.73.1 to 110.232.73.254110.232.73.255254
75110.232.74.0/24110.232.74.1 to 110.232.74.254110.232.74.255254
76110.232.75.0/24110.232.75.1 to 110.232.75.254110.232.75.255254
77110.232.76.0/24110.232.76.1 to 110.232.76.254110.232.76.255254
78110.232.77.0/24110.232.77.1 to 110.232.77.254110.232.77.255254
79110.232.78.0/24110.232.78.1 to 110.232.78.254110.232.78.255254
80110.232.79.0/24110.232.79.1 to 110.232.79.254110.232.79.255254
81110.232.80.0/24110.232.80.1 to 110.232.80.254110.232.80.255254
82110.232.81.0/24110.232.81.1 to 110.232.81.254110.232.81.255254
83110.232.82.0/24110.232.82.1 to 110.232.82.254110.232.82.255254
84110.232.83.0/24110.232.83.1 to 110.232.83.254110.232.83.255254
85110.232.84.0/24110.232.84.1 to 110.232.84.254110.232.84.255254
86110.232.85.0/24110.232.85.1 to 110.232.85.254110.232.85.255254
87110.232.86.0/24110.232.86.1 to 110.232.86.254110.232.86.255254
88110.232.87.0/24110.232.87.1 to 110.232.87.254110.232.87.255254
89110.232.88.0/24110.232.88.1 to 110.232.88.254110.232.88.255254
90110.232.89.0/24110.232.89.1 to 110.232.89.254110.232.89.255254
91110.232.90.0/24110.232.90.1 to 110.232.90.254110.232.90.255254
92110.232.91.0/24110.232.91.1 to 110.232.91.254110.232.91.255254
93110.232.92.0/24110.232.92.1 to 110.232.92.254110.232.92.255254
94110.232.93.0/24110.232.93.1 to 110.232.93.254110.232.93.255254
95110.232.94.0/24110.232.94.1 to 110.232.94.254110.232.94.255254
96110.232.95.0/24110.232.95.1 to 110.232.95.254110.232.95.255254
97110.232.96.0/24110.232.96.1 to 110.232.96.254110.232.96.255254
98110.232.97.0/24110.232.97.1 to 110.232.97.254110.232.97.255254
99110.232.98.0/24110.232.98.1 to 110.232.98.254110.232.98.255254
100110.232.99.0/24110.232.99.1 to 110.232.99.254110.232.99.255254
101110.232.100.0/24110.232.100.1 to 110.232.100.254110.232.100.255254
102110.232.101.0/24110.232.101.1 to 110.232.101.254110.232.101.255254
103110.232.102.0/24110.232.102.1 to 110.232.102.254110.232.102.255254
104110.232.103.0/24110.232.103.1 to 110.232.103.254110.232.103.255254
105110.232.104.0/24110.232.104.1 to 110.232.104.254110.232.104.255254
106110.232.105.0/24110.232.105.1 to 110.232.105.254110.232.105.255254
107110.232.106.0/24110.232.106.1 to 110.232.106.254110.232.106.255254
108110.232.107.0/24110.232.107.1 to 110.232.107.254110.232.107.255254
109110.232.108.0/24110.232.108.1 to 110.232.108.254110.232.108.255254
110110.232.109.0/24110.232.109.1 to 110.232.109.254110.232.109.255254
111110.232.110.0/24110.232.110.1 to 110.232.110.254110.232.110.255254
112110.232.111.0/24110.232.111.1 to 110.232.111.254110.232.111.255254
113110.232.112.0/24110.232.112.1 to 110.232.112.254110.232.112.255254
114110.232.113.0/24110.232.113.1 to 110.232.113.254110.232.113.255254
115110.232.114.0/24110.232.114.1 to 110.232.114.254110.232.114.255254
116110.232.115.0/24110.232.115.1 to 110.232.115.254110.232.115.255254
117110.232.116.0/24110.232.116.1 to 110.232.116.254110.232.116.255254
118110.232.117.0/24110.232.117.1 to 110.232.117.254110.232.117.255254
119110.232.118.0/24110.232.118.1 to 110.232.118.254110.232.118.255254
120110.232.119.0/24110.232.119.1 to 110.232.119.254110.232.119.255254
121110.232.120.0/24110.232.120.1 to 110.232.120.254110.232.120.255254
122110.232.121.0/24110.232.121.1 to 110.232.121.254110.232.121.255254
123110.232.122.0/24110.232.122.1 to 110.232.122.254110.232.122.255254
124110.232.123.0/24110.232.123.1 to 110.232.123.254110.232.123.255254
125110.232.124.0/24110.232.124.1 to 110.232.124.254110.232.124.255254
126110.232.125.0/24110.232.125.1 to 110.232.125.254110.232.125.255254
127110.232.126.0/24110.232.126.1 to 110.232.126.254110.232.126.255254
128110.232.127.0/24110.232.127.1 to 110.232.127.254110.232.127.255254
129110.232.128.0/24110.232.128.1 to 110.232.128.254110.232.128.255254
130110.232.129.0/24110.232.129.1 to 110.232.129.254110.232.129.255254
131110.232.130.0/24110.232.130.1 to 110.232.130.254110.232.130.255254
132110.232.131.0/24110.232.131.1 to 110.232.131.254110.232.131.255254
133110.232.132.0/24110.232.132.1 to 110.232.132.254110.232.132.255254
134110.232.133.0/24110.232.133.1 to 110.232.133.254110.232.133.255254
135110.232.134.0/24110.232.134.1 to 110.232.134.254110.232.134.255254
136110.232.135.0/24110.232.135.1 to 110.232.135.254110.232.135.255254
137110.232.136.0/24110.232.136.1 to 110.232.136.254110.232.136.255254
138110.232.137.0/24110.232.137.1 to 110.232.137.254110.232.137.255254
139110.232.138.0/24110.232.138.1 to 110.232.138.254110.232.138.255254
140110.232.139.0/24110.232.139.1 to 110.232.139.254110.232.139.255254
141110.232.140.0/24110.232.140.1 to 110.232.140.254110.232.140.255254
142110.232.141.0/24110.232.141.1 to 110.232.141.254110.232.141.255254
143110.232.142.0/24110.232.142.1 to 110.232.142.254110.232.142.255254
144110.232.143.0/24110.232.143.1 to 110.232.143.254110.232.143.255254
145110.232.144.0/24110.232.144.1 to 110.232.144.254110.232.144.255254
146110.232.145.0/24110.232.145.1 to 110.232.145.254110.232.145.255254
147110.232.146.0/24110.232.146.1 to 110.232.146.254110.232.146.255254
148110.232.147.0/24110.232.147.1 to 110.232.147.254110.232.147.255254
149110.232.148.0/24110.232.148.1 to 110.232.148.254110.232.148.255254
150110.232.149.0/24110.232.149.1 to 110.232.149.254110.232.149.255254
151110.232.150.0/24110.232.150.1 to 110.232.150.254110.232.150.255254
152110.232.151.0/24110.232.151.1 to 110.232.151.254110.232.151.255254
153110.232.152.0/24110.232.152.1 to 110.232.152.254110.232.152.255254
154110.232.153.0/24110.232.153.1 to 110.232.153.254110.232.153.255254
155110.232.154.0/24110.232.154.1 to 110.232.154.254110.232.154.255254
156110.232.155.0/24110.232.155.1 to 110.232.155.254110.232.155.255254
157110.232.156.0/24110.232.156.1 to 110.232.156.254110.232.156.255254
158110.232.157.0/24110.232.157.1 to 110.232.157.254110.232.157.255254
159110.232.158.0/24110.232.158.1 to 110.232.158.254110.232.158.255254
160110.232.159.0/24110.232.159.1 to 110.232.159.254110.232.159.255254
161110.232.160.0/24110.232.160.1 to 110.232.160.254110.232.160.255254
162110.232.161.0/24110.232.161.1 to 110.232.161.254110.232.161.255254
163110.232.162.0/24110.232.162.1 to 110.232.162.254110.232.162.255254
164110.232.163.0/24110.232.163.1 to 110.232.163.254110.232.163.255254
165110.232.164.0/24110.232.164.1 to 110.232.164.254110.232.164.255254
166110.232.165.0/24110.232.165.1 to 110.232.165.254110.232.165.255254
167110.232.166.0/24110.232.166.1 to 110.232.166.254110.232.166.255254
168110.232.167.0/24110.232.167.1 to 110.232.167.254110.232.167.255254
169110.232.168.0/24110.232.168.1 to 110.232.168.254110.232.168.255254
170110.232.169.0/24110.232.169.1 to 110.232.169.254110.232.169.255254
171110.232.170.0/24110.232.170.1 to 110.232.170.254110.232.170.255254
172110.232.171.0/24110.232.171.1 to 110.232.171.254110.232.171.255254
173110.232.172.0/24110.232.172.1 to 110.232.172.254110.232.172.255254
174110.232.173.0/24110.232.173.1 to 110.232.173.254110.232.173.255254
175110.232.174.0/24110.232.174.1 to 110.232.174.254110.232.174.255254
176110.232.175.0/24110.232.175.1 to 110.232.175.254110.232.175.255254
177110.232.176.0/24110.232.176.1 to 110.232.176.254110.232.176.255254
178110.232.177.0/24110.232.177.1 to 110.232.177.254110.232.177.255254
179110.232.178.0/24110.232.178.1 to 110.232.178.254110.232.178.255254
180110.232.179.0/24110.232.179.1 to 110.232.179.254110.232.179.255254
181110.232.180.0/24110.232.180.1 to 110.232.180.254110.232.180.255254
182110.232.181.0/24110.232.181.1 to 110.232.181.254110.232.181.255254
183110.232.182.0/24110.232.182.1 to 110.232.182.254110.232.182.255254
184110.232.183.0/24110.232.183.1 to 110.232.183.254110.232.183.255254
185110.232.184.0/24110.232.184.1 to 110.232.184.254110.232.184.255254
186110.232.185.0/24110.232.185.1 to 110.232.185.254110.232.185.255254
187110.232.186.0/24110.232.186.1 to 110.232.186.254110.232.186.255254
188110.232.187.0/24110.232.187.1 to 110.232.187.254110.232.187.255254
189110.232.188.0/24110.232.188.1 to 110.232.188.254110.232.188.255254
190110.232.189.0/24110.232.189.1 to 110.232.189.254110.232.189.255254
191110.232.190.0/24110.232.190.1 to 110.232.190.254110.232.190.255254
192110.232.191.0/24110.232.191.1 to 110.232.191.254110.232.191.255254
193110.232.192.0/24110.232.192.1 to 110.232.192.254110.232.192.255254
194110.232.193.0/24110.232.193.1 to 110.232.193.254110.232.193.255254
195110.232.194.0/24110.232.194.1 to 110.232.194.254110.232.194.255254
196110.232.195.0/24110.232.195.1 to 110.232.195.254110.232.195.255254
197110.232.196.0/24110.232.196.1 to 110.232.196.254110.232.196.255254
198110.232.197.0/24110.232.197.1 to 110.232.197.254110.232.197.255254
199110.232.198.0/24110.232.198.1 to 110.232.198.254110.232.198.255254
200110.232.199.0/24110.232.199.1 to 110.232.199.254110.232.199.255254
201110.232.200.0/24110.232.200.1 to 110.232.200.254110.232.200.255254
202110.232.201.0/24110.232.201.1 to 110.232.201.254110.232.201.255254
203110.232.202.0/24110.232.202.1 to 110.232.202.254110.232.202.255254
204110.232.203.0/24110.232.203.1 to 110.232.203.254110.232.203.255254
205110.232.204.0/24110.232.204.1 to 110.232.204.254110.232.204.255254
206110.232.205.0/24110.232.205.1 to 110.232.205.254110.232.205.255254
207110.232.206.0/24110.232.206.1 to 110.232.206.254110.232.206.255254
208110.232.207.0/24110.232.207.1 to 110.232.207.254110.232.207.255254
209110.232.208.0/24110.232.208.1 to 110.232.208.254110.232.208.255254
210110.232.209.0/24110.232.209.1 to 110.232.209.254110.232.209.255254
211110.232.210.0/24110.232.210.1 to 110.232.210.254110.232.210.255254
212110.232.211.0/24110.232.211.1 to 110.232.211.254110.232.211.255254
213110.232.212.0/24110.232.212.1 to 110.232.212.254110.232.212.255254
214110.232.213.0/24110.232.213.1 to 110.232.213.254110.232.213.255254
215110.232.214.0/24110.232.214.1 to 110.232.214.254110.232.214.255254
216110.232.215.0/24110.232.215.1 to 110.232.215.254110.232.215.255254
217110.232.216.0/24110.232.216.1 to 110.232.216.254110.232.216.255254
218110.232.217.0/24110.232.217.1 to 110.232.217.254110.232.217.255254
219110.232.218.0/24110.232.218.1 to 110.232.218.254110.232.218.255254
220110.232.219.0/24110.232.219.1 to 110.232.219.254110.232.219.255254
221110.232.220.0/24110.232.220.1 to 110.232.220.254110.232.220.255254
222110.232.221.0/24110.232.221.1 to 110.232.221.254110.232.221.255254
223110.232.222.0/24110.232.222.1 to 110.232.222.254110.232.222.255254
224110.232.223.0/24110.232.223.1 to 110.232.223.254110.232.223.255254
225110.232.224.0/24110.232.224.1 to 110.232.224.254110.232.224.255254
226110.232.225.0/24110.232.225.1 to 110.232.225.254110.232.225.255254
227110.232.226.0/24110.232.226.1 to 110.232.226.254110.232.226.255254
228110.232.227.0/24110.232.227.1 to 110.232.227.254110.232.227.255254
229110.232.228.0/24110.232.228.1 to 110.232.228.254110.232.228.255254
230110.232.229.0/24110.232.229.1 to 110.232.229.254110.232.229.255254
231110.232.230.0/24110.232.230.1 to 110.232.230.254110.232.230.255254
232110.232.231.0/24110.232.231.1 to 110.232.231.254110.232.231.255254
233110.232.232.0/24110.232.232.1 to 110.232.232.254110.232.232.255254
234110.232.233.0/24110.232.233.1 to 110.232.233.254110.232.233.255254
235110.232.234.0/24110.232.234.1 to 110.232.234.254110.232.234.255254
236110.232.235.0/24110.232.235.1 to 110.232.235.254110.232.235.255254
237110.232.236.0/24110.232.236.1 to 110.232.236.254110.232.236.255254
238110.232.237.0/24110.232.237.1 to 110.232.237.254110.232.237.255254
239110.232.238.0/24110.232.238.1 to 110.232.238.254110.232.238.255254
240110.232.239.0/24110.232.239.1 to 110.232.239.254110.232.239.255254
241110.232.240.0/24110.232.240.1 to 110.232.240.254110.232.240.255254
242110.232.241.0/24110.232.241.1 to 110.232.241.254110.232.241.255254
243110.232.242.0/24110.232.242.1 to 110.232.242.254110.232.242.255254
244110.232.243.0/24110.232.243.1 to 110.232.243.254110.232.243.255254
245110.232.244.0/24110.232.244.1 to 110.232.244.254110.232.244.255254
246110.232.245.0/24110.232.245.1 to 110.232.245.254110.232.245.255254
247110.232.246.0/24110.232.246.1 to 110.232.246.254110.232.246.255254
248110.232.247.0/24110.232.247.1 to 110.232.247.254110.232.247.255254
249110.232.248.0/24110.232.248.1 to 110.232.248.254110.232.248.255254
250110.232.249.0/24110.232.249.1 to 110.232.249.254110.232.249.255254
251110.232.250.0/24110.232.250.1 to 110.232.250.254110.232.250.255254
252110.232.251.0/24110.232.251.1 to 110.232.251.254110.232.251.255254
253110.232.252.0/24110.232.252.1 to 110.232.252.254110.232.252.255254
254110.232.253.0/24110.232.253.1 to 110.232.253.254110.232.253.255254
255110.232.254.0/24110.232.254.1 to 110.232.254.254110.232.254.255254
256110.232.255.0/24110.232.255.1 to 110.232.255.254110.232.255.255254

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.