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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.

Network118.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
118.0.0.0
Broadcast address
119.255.255.255
First usable
118.0.0.1
Last usable
119.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
A (default /8)
As numbers
Hex 76000000 · Integer 1979711488 to 2013265919
Reverse DNS zones
118.in-addr.arpa
119.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110110.00000000.00000000.00000000118.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network01110110.00000000.00000000.00000000118.0.0.0
Broadcast01110111.11111111.11111111.11111111119.255.255.255
Split into smaller subnets/15
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

118.0.0.0/7 makes 256 subnets of /15.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1118.0.0.0/15118.0.0.1 to 118.1.255.254118.1.255.255131,070
2118.2.0.0/15118.2.0.1 to 118.3.255.254118.3.255.255131,070
3118.4.0.0/15118.4.0.1 to 118.5.255.254118.5.255.255131,070
4118.6.0.0/15118.6.0.1 to 118.7.255.254118.7.255.255131,070
5118.8.0.0/15118.8.0.1 to 118.9.255.254118.9.255.255131,070
6118.10.0.0/15118.10.0.1 to 118.11.255.254118.11.255.255131,070
7118.12.0.0/15118.12.0.1 to 118.13.255.254118.13.255.255131,070
8118.14.0.0/15118.14.0.1 to 118.15.255.254118.15.255.255131,070
9118.16.0.0/15118.16.0.1 to 118.17.255.254118.17.255.255131,070
10118.18.0.0/15118.18.0.1 to 118.19.255.254118.19.255.255131,070
11118.20.0.0/15118.20.0.1 to 118.21.255.254118.21.255.255131,070
12118.22.0.0/15118.22.0.1 to 118.23.255.254118.23.255.255131,070
13118.24.0.0/15118.24.0.1 to 118.25.255.254118.25.255.255131,070
14118.26.0.0/15118.26.0.1 to 118.27.255.254118.27.255.255131,070
15118.28.0.0/15118.28.0.1 to 118.29.255.254118.29.255.255131,070
16118.30.0.0/15118.30.0.1 to 118.31.255.254118.31.255.255131,070
17118.32.0.0/15118.32.0.1 to 118.33.255.254118.33.255.255131,070
18118.34.0.0/15118.34.0.1 to 118.35.255.254118.35.255.255131,070
19118.36.0.0/15118.36.0.1 to 118.37.255.254118.37.255.255131,070
20118.38.0.0/15118.38.0.1 to 118.39.255.254118.39.255.255131,070
21118.40.0.0/15118.40.0.1 to 118.41.255.254118.41.255.255131,070
22118.42.0.0/15118.42.0.1 to 118.43.255.254118.43.255.255131,070
23118.44.0.0/15118.44.0.1 to 118.45.255.254118.45.255.255131,070
24118.46.0.0/15118.46.0.1 to 118.47.255.254118.47.255.255131,070
25118.48.0.0/15118.48.0.1 to 118.49.255.254118.49.255.255131,070
26118.50.0.0/15118.50.0.1 to 118.51.255.254118.51.255.255131,070
27118.52.0.0/15118.52.0.1 to 118.53.255.254118.53.255.255131,070
28118.54.0.0/15118.54.0.1 to 118.55.255.254118.55.255.255131,070
29118.56.0.0/15118.56.0.1 to 118.57.255.254118.57.255.255131,070
30118.58.0.0/15118.58.0.1 to 118.59.255.254118.59.255.255131,070
31118.60.0.0/15118.60.0.1 to 118.61.255.254118.61.255.255131,070
32118.62.0.0/15118.62.0.1 to 118.63.255.254118.63.255.255131,070
33118.64.0.0/15118.64.0.1 to 118.65.255.254118.65.255.255131,070
34118.66.0.0/15118.66.0.1 to 118.67.255.254118.67.255.255131,070
35118.68.0.0/15118.68.0.1 to 118.69.255.254118.69.255.255131,070
36118.70.0.0/15118.70.0.1 to 118.71.255.254118.71.255.255131,070
37118.72.0.0/15118.72.0.1 to 118.73.255.254118.73.255.255131,070
38118.74.0.0/15118.74.0.1 to 118.75.255.254118.75.255.255131,070
39118.76.0.0/15118.76.0.1 to 118.77.255.254118.77.255.255131,070
40118.78.0.0/15118.78.0.1 to 118.79.255.254118.79.255.255131,070
41118.80.0.0/15118.80.0.1 to 118.81.255.254118.81.255.255131,070
42118.82.0.0/15118.82.0.1 to 118.83.255.254118.83.255.255131,070
43118.84.0.0/15118.84.0.1 to 118.85.255.254118.85.255.255131,070
44118.86.0.0/15118.86.0.1 to 118.87.255.254118.87.255.255131,070
45118.88.0.0/15118.88.0.1 to 118.89.255.254118.89.255.255131,070
46118.90.0.0/15118.90.0.1 to 118.91.255.254118.91.255.255131,070
47118.92.0.0/15118.92.0.1 to 118.93.255.254118.93.255.255131,070
48118.94.0.0/15118.94.0.1 to 118.95.255.254118.95.255.255131,070
49118.96.0.0/15118.96.0.1 to 118.97.255.254118.97.255.255131,070
50118.98.0.0/15118.98.0.1 to 118.99.255.254118.99.255.255131,070
51118.100.0.0/15118.100.0.1 to 118.101.255.254118.101.255.255131,070
52118.102.0.0/15118.102.0.1 to 118.103.255.254118.103.255.255131,070
53118.104.0.0/15118.104.0.1 to 118.105.255.254118.105.255.255131,070
54118.106.0.0/15118.106.0.1 to 118.107.255.254118.107.255.255131,070
55118.108.0.0/15118.108.0.1 to 118.109.255.254118.109.255.255131,070
56118.110.0.0/15118.110.0.1 to 118.111.255.254118.111.255.255131,070
57118.112.0.0/15118.112.0.1 to 118.113.255.254118.113.255.255131,070
58118.114.0.0/15118.114.0.1 to 118.115.255.254118.115.255.255131,070
59118.116.0.0/15118.116.0.1 to 118.117.255.254118.117.255.255131,070
60118.118.0.0/15118.118.0.1 to 118.119.255.254118.119.255.255131,070
61118.120.0.0/15118.120.0.1 to 118.121.255.254118.121.255.255131,070
62118.122.0.0/15118.122.0.1 to 118.123.255.254118.123.255.255131,070
63118.124.0.0/15118.124.0.1 to 118.125.255.254118.125.255.255131,070
64118.126.0.0/15118.126.0.1 to 118.127.255.254118.127.255.255131,070
65118.128.0.0/15118.128.0.1 to 118.129.255.254118.129.255.255131,070
66118.130.0.0/15118.130.0.1 to 118.131.255.254118.131.255.255131,070
67118.132.0.0/15118.132.0.1 to 118.133.255.254118.133.255.255131,070
68118.134.0.0/15118.134.0.1 to 118.135.255.254118.135.255.255131,070
69118.136.0.0/15118.136.0.1 to 118.137.255.254118.137.255.255131,070
70118.138.0.0/15118.138.0.1 to 118.139.255.254118.139.255.255131,070
71118.140.0.0/15118.140.0.1 to 118.141.255.254118.141.255.255131,070
72118.142.0.0/15118.142.0.1 to 118.143.255.254118.143.255.255131,070
73118.144.0.0/15118.144.0.1 to 118.145.255.254118.145.255.255131,070
74118.146.0.0/15118.146.0.1 to 118.147.255.254118.147.255.255131,070
75118.148.0.0/15118.148.0.1 to 118.149.255.254118.149.255.255131,070
76118.150.0.0/15118.150.0.1 to 118.151.255.254118.151.255.255131,070
77118.152.0.0/15118.152.0.1 to 118.153.255.254118.153.255.255131,070
78118.154.0.0/15118.154.0.1 to 118.155.255.254118.155.255.255131,070
79118.156.0.0/15118.156.0.1 to 118.157.255.254118.157.255.255131,070
80118.158.0.0/15118.158.0.1 to 118.159.255.254118.159.255.255131,070
81118.160.0.0/15118.160.0.1 to 118.161.255.254118.161.255.255131,070
82118.162.0.0/15118.162.0.1 to 118.163.255.254118.163.255.255131,070
83118.164.0.0/15118.164.0.1 to 118.165.255.254118.165.255.255131,070
84118.166.0.0/15118.166.0.1 to 118.167.255.254118.167.255.255131,070
85118.168.0.0/15118.168.0.1 to 118.169.255.254118.169.255.255131,070
86118.170.0.0/15118.170.0.1 to 118.171.255.254118.171.255.255131,070
87118.172.0.0/15118.172.0.1 to 118.173.255.254118.173.255.255131,070
88118.174.0.0/15118.174.0.1 to 118.175.255.254118.175.255.255131,070
89118.176.0.0/15118.176.0.1 to 118.177.255.254118.177.255.255131,070
90118.178.0.0/15118.178.0.1 to 118.179.255.254118.179.255.255131,070
91118.180.0.0/15118.180.0.1 to 118.181.255.254118.181.255.255131,070
92118.182.0.0/15118.182.0.1 to 118.183.255.254118.183.255.255131,070
93118.184.0.0/15118.184.0.1 to 118.185.255.254118.185.255.255131,070
94118.186.0.0/15118.186.0.1 to 118.187.255.254118.187.255.255131,070
95118.188.0.0/15118.188.0.1 to 118.189.255.254118.189.255.255131,070
96118.190.0.0/15118.190.0.1 to 118.191.255.254118.191.255.255131,070
97118.192.0.0/15118.192.0.1 to 118.193.255.254118.193.255.255131,070
98118.194.0.0/15118.194.0.1 to 118.195.255.254118.195.255.255131,070
99118.196.0.0/15118.196.0.1 to 118.197.255.254118.197.255.255131,070
100118.198.0.0/15118.198.0.1 to 118.199.255.254118.199.255.255131,070
101118.200.0.0/15118.200.0.1 to 118.201.255.254118.201.255.255131,070
102118.202.0.0/15118.202.0.1 to 118.203.255.254118.203.255.255131,070
103118.204.0.0/15118.204.0.1 to 118.205.255.254118.205.255.255131,070
104118.206.0.0/15118.206.0.1 to 118.207.255.254118.207.255.255131,070
105118.208.0.0/15118.208.0.1 to 118.209.255.254118.209.255.255131,070
106118.210.0.0/15118.210.0.1 to 118.211.255.254118.211.255.255131,070
107118.212.0.0/15118.212.0.1 to 118.213.255.254118.213.255.255131,070
108118.214.0.0/15118.214.0.1 to 118.215.255.254118.215.255.255131,070
109118.216.0.0/15118.216.0.1 to 118.217.255.254118.217.255.255131,070
110118.218.0.0/15118.218.0.1 to 118.219.255.254118.219.255.255131,070
111118.220.0.0/15118.220.0.1 to 118.221.255.254118.221.255.255131,070
112118.222.0.0/15118.222.0.1 to 118.223.255.254118.223.255.255131,070
113118.224.0.0/15118.224.0.1 to 118.225.255.254118.225.255.255131,070
114118.226.0.0/15118.226.0.1 to 118.227.255.254118.227.255.255131,070
115118.228.0.0/15118.228.0.1 to 118.229.255.254118.229.255.255131,070
116118.230.0.0/15118.230.0.1 to 118.231.255.254118.231.255.255131,070
117118.232.0.0/15118.232.0.1 to 118.233.255.254118.233.255.255131,070
118118.234.0.0/15118.234.0.1 to 118.235.255.254118.235.255.255131,070
119118.236.0.0/15118.236.0.1 to 118.237.255.254118.237.255.255131,070
120118.238.0.0/15118.238.0.1 to 118.239.255.254118.239.255.255131,070
121118.240.0.0/15118.240.0.1 to 118.241.255.254118.241.255.255131,070
122118.242.0.0/15118.242.0.1 to 118.243.255.254118.243.255.255131,070
123118.244.0.0/15118.244.0.1 to 118.245.255.254118.245.255.255131,070
124118.246.0.0/15118.246.0.1 to 118.247.255.254118.247.255.255131,070
125118.248.0.0/15118.248.0.1 to 118.249.255.254118.249.255.255131,070
126118.250.0.0/15118.250.0.1 to 118.251.255.254118.251.255.255131,070
127118.252.0.0/15118.252.0.1 to 118.253.255.254118.253.255.255131,070
128118.254.0.0/15118.254.0.1 to 118.255.255.254118.255.255.255131,070
129119.0.0.0/15119.0.0.1 to 119.1.255.254119.1.255.255131,070
130119.2.0.0/15119.2.0.1 to 119.3.255.254119.3.255.255131,070
131119.4.0.0/15119.4.0.1 to 119.5.255.254119.5.255.255131,070
132119.6.0.0/15119.6.0.1 to 119.7.255.254119.7.255.255131,070
133119.8.0.0/15119.8.0.1 to 119.9.255.254119.9.255.255131,070
134119.10.0.0/15119.10.0.1 to 119.11.255.254119.11.255.255131,070
135119.12.0.0/15119.12.0.1 to 119.13.255.254119.13.255.255131,070
136119.14.0.0/15119.14.0.1 to 119.15.255.254119.15.255.255131,070
137119.16.0.0/15119.16.0.1 to 119.17.255.254119.17.255.255131,070
138119.18.0.0/15119.18.0.1 to 119.19.255.254119.19.255.255131,070
139119.20.0.0/15119.20.0.1 to 119.21.255.254119.21.255.255131,070
140119.22.0.0/15119.22.0.1 to 119.23.255.254119.23.255.255131,070
141119.24.0.0/15119.24.0.1 to 119.25.255.254119.25.255.255131,070
142119.26.0.0/15119.26.0.1 to 119.27.255.254119.27.255.255131,070
143119.28.0.0/15119.28.0.1 to 119.29.255.254119.29.255.255131,070
144119.30.0.0/15119.30.0.1 to 119.31.255.254119.31.255.255131,070
145119.32.0.0/15119.32.0.1 to 119.33.255.254119.33.255.255131,070
146119.34.0.0/15119.34.0.1 to 119.35.255.254119.35.255.255131,070
147119.36.0.0/15119.36.0.1 to 119.37.255.254119.37.255.255131,070
148119.38.0.0/15119.38.0.1 to 119.39.255.254119.39.255.255131,070
149119.40.0.0/15119.40.0.1 to 119.41.255.254119.41.255.255131,070
150119.42.0.0/15119.42.0.1 to 119.43.255.254119.43.255.255131,070
151119.44.0.0/15119.44.0.1 to 119.45.255.254119.45.255.255131,070
152119.46.0.0/15119.46.0.1 to 119.47.255.254119.47.255.255131,070
153119.48.0.0/15119.48.0.1 to 119.49.255.254119.49.255.255131,070
154119.50.0.0/15119.50.0.1 to 119.51.255.254119.51.255.255131,070
155119.52.0.0/15119.52.0.1 to 119.53.255.254119.53.255.255131,070
156119.54.0.0/15119.54.0.1 to 119.55.255.254119.55.255.255131,070
157119.56.0.0/15119.56.0.1 to 119.57.255.254119.57.255.255131,070
158119.58.0.0/15119.58.0.1 to 119.59.255.254119.59.255.255131,070
159119.60.0.0/15119.60.0.1 to 119.61.255.254119.61.255.255131,070
160119.62.0.0/15119.62.0.1 to 119.63.255.254119.63.255.255131,070
161119.64.0.0/15119.64.0.1 to 119.65.255.254119.65.255.255131,070
162119.66.0.0/15119.66.0.1 to 119.67.255.254119.67.255.255131,070
163119.68.0.0/15119.68.0.1 to 119.69.255.254119.69.255.255131,070
164119.70.0.0/15119.70.0.1 to 119.71.255.254119.71.255.255131,070
165119.72.0.0/15119.72.0.1 to 119.73.255.254119.73.255.255131,070
166119.74.0.0/15119.74.0.1 to 119.75.255.254119.75.255.255131,070
167119.76.0.0/15119.76.0.1 to 119.77.255.254119.77.255.255131,070
168119.78.0.0/15119.78.0.1 to 119.79.255.254119.79.255.255131,070
169119.80.0.0/15119.80.0.1 to 119.81.255.254119.81.255.255131,070
170119.82.0.0/15119.82.0.1 to 119.83.255.254119.83.255.255131,070
171119.84.0.0/15119.84.0.1 to 119.85.255.254119.85.255.255131,070
172119.86.0.0/15119.86.0.1 to 119.87.255.254119.87.255.255131,070
173119.88.0.0/15119.88.0.1 to 119.89.255.254119.89.255.255131,070
174119.90.0.0/15119.90.0.1 to 119.91.255.254119.91.255.255131,070
175119.92.0.0/15119.92.0.1 to 119.93.255.254119.93.255.255131,070
176119.94.0.0/15119.94.0.1 to 119.95.255.254119.95.255.255131,070
177119.96.0.0/15119.96.0.1 to 119.97.255.254119.97.255.255131,070
178119.98.0.0/15119.98.0.1 to 119.99.255.254119.99.255.255131,070
179119.100.0.0/15119.100.0.1 to 119.101.255.254119.101.255.255131,070
180119.102.0.0/15119.102.0.1 to 119.103.255.254119.103.255.255131,070
181119.104.0.0/15119.104.0.1 to 119.105.255.254119.105.255.255131,070
182119.106.0.0/15119.106.0.1 to 119.107.255.254119.107.255.255131,070
183119.108.0.0/15119.108.0.1 to 119.109.255.254119.109.255.255131,070
184119.110.0.0/15119.110.0.1 to 119.111.255.254119.111.255.255131,070
185119.112.0.0/15119.112.0.1 to 119.113.255.254119.113.255.255131,070
186119.114.0.0/15119.114.0.1 to 119.115.255.254119.115.255.255131,070
187119.116.0.0/15119.116.0.1 to 119.117.255.254119.117.255.255131,070
188119.118.0.0/15119.118.0.1 to 119.119.255.254119.119.255.255131,070
189119.120.0.0/15119.120.0.1 to 119.121.255.254119.121.255.255131,070
190119.122.0.0/15119.122.0.1 to 119.123.255.254119.123.255.255131,070
191119.124.0.0/15119.124.0.1 to 119.125.255.254119.125.255.255131,070
192119.126.0.0/15119.126.0.1 to 119.127.255.254119.127.255.255131,070
193119.128.0.0/15119.128.0.1 to 119.129.255.254119.129.255.255131,070
194119.130.0.0/15119.130.0.1 to 119.131.255.254119.131.255.255131,070
195119.132.0.0/15119.132.0.1 to 119.133.255.254119.133.255.255131,070
196119.134.0.0/15119.134.0.1 to 119.135.255.254119.135.255.255131,070
197119.136.0.0/15119.136.0.1 to 119.137.255.254119.137.255.255131,070
198119.138.0.0/15119.138.0.1 to 119.139.255.254119.139.255.255131,070
199119.140.0.0/15119.140.0.1 to 119.141.255.254119.141.255.255131,070
200119.142.0.0/15119.142.0.1 to 119.143.255.254119.143.255.255131,070
201119.144.0.0/15119.144.0.1 to 119.145.255.254119.145.255.255131,070
202119.146.0.0/15119.146.0.1 to 119.147.255.254119.147.255.255131,070
203119.148.0.0/15119.148.0.1 to 119.149.255.254119.149.255.255131,070
204119.150.0.0/15119.150.0.1 to 119.151.255.254119.151.255.255131,070
205119.152.0.0/15119.152.0.1 to 119.153.255.254119.153.255.255131,070
206119.154.0.0/15119.154.0.1 to 119.155.255.254119.155.255.255131,070
207119.156.0.0/15119.156.0.1 to 119.157.255.254119.157.255.255131,070
208119.158.0.0/15119.158.0.1 to 119.159.255.254119.159.255.255131,070
209119.160.0.0/15119.160.0.1 to 119.161.255.254119.161.255.255131,070
210119.162.0.0/15119.162.0.1 to 119.163.255.254119.163.255.255131,070
211119.164.0.0/15119.164.0.1 to 119.165.255.254119.165.255.255131,070
212119.166.0.0/15119.166.0.1 to 119.167.255.254119.167.255.255131,070
213119.168.0.0/15119.168.0.1 to 119.169.255.254119.169.255.255131,070
214119.170.0.0/15119.170.0.1 to 119.171.255.254119.171.255.255131,070
215119.172.0.0/15119.172.0.1 to 119.173.255.254119.173.255.255131,070
216119.174.0.0/15119.174.0.1 to 119.175.255.254119.175.255.255131,070
217119.176.0.0/15119.176.0.1 to 119.177.255.254119.177.255.255131,070
218119.178.0.0/15119.178.0.1 to 119.179.255.254119.179.255.255131,070
219119.180.0.0/15119.180.0.1 to 119.181.255.254119.181.255.255131,070
220119.182.0.0/15119.182.0.1 to 119.183.255.254119.183.255.255131,070
221119.184.0.0/15119.184.0.1 to 119.185.255.254119.185.255.255131,070
222119.186.0.0/15119.186.0.1 to 119.187.255.254119.187.255.255131,070
223119.188.0.0/15119.188.0.1 to 119.189.255.254119.189.255.255131,070
224119.190.0.0/15119.190.0.1 to 119.191.255.254119.191.255.255131,070
225119.192.0.0/15119.192.0.1 to 119.193.255.254119.193.255.255131,070
226119.194.0.0/15119.194.0.1 to 119.195.255.254119.195.255.255131,070
227119.196.0.0/15119.196.0.1 to 119.197.255.254119.197.255.255131,070
228119.198.0.0/15119.198.0.1 to 119.199.255.254119.199.255.255131,070
229119.200.0.0/15119.200.0.1 to 119.201.255.254119.201.255.255131,070
230119.202.0.0/15119.202.0.1 to 119.203.255.254119.203.255.255131,070
231119.204.0.0/15119.204.0.1 to 119.205.255.254119.205.255.255131,070
232119.206.0.0/15119.206.0.1 to 119.207.255.254119.207.255.255131,070
233119.208.0.0/15119.208.0.1 to 119.209.255.254119.209.255.255131,070
234119.210.0.0/15119.210.0.1 to 119.211.255.254119.211.255.255131,070
235119.212.0.0/15119.212.0.1 to 119.213.255.254119.213.255.255131,070
236119.214.0.0/15119.214.0.1 to 119.215.255.254119.215.255.255131,070
237119.216.0.0/15119.216.0.1 to 119.217.255.254119.217.255.255131,070
238119.218.0.0/15119.218.0.1 to 119.219.255.254119.219.255.255131,070
239119.220.0.0/15119.220.0.1 to 119.221.255.254119.221.255.255131,070
240119.222.0.0/15119.222.0.1 to 119.223.255.254119.223.255.255131,070
241119.224.0.0/15119.224.0.1 to 119.225.255.254119.225.255.255131,070
242119.226.0.0/15119.226.0.1 to 119.227.255.254119.227.255.255131,070
243119.228.0.0/15119.228.0.1 to 119.229.255.254119.229.255.255131,070
244119.230.0.0/15119.230.0.1 to 119.231.255.254119.231.255.255131,070
245119.232.0.0/15119.232.0.1 to 119.233.255.254119.233.255.255131,070
246119.234.0.0/15119.234.0.1 to 119.235.255.254119.235.255.255131,070
247119.236.0.0/15119.236.0.1 to 119.237.255.254119.237.255.255131,070
248119.238.0.0/15119.238.0.1 to 119.239.255.254119.239.255.255131,070
249119.240.0.0/15119.240.0.1 to 119.241.255.254119.241.255.255131,070
250119.242.0.0/15119.242.0.1 to 119.243.255.254119.243.255.255131,070
251119.244.0.0/15119.244.0.1 to 119.245.255.254119.245.255.255131,070
252119.246.0.0/15119.246.0.1 to 119.247.255.254119.247.255.255131,070
253119.248.0.0/15119.248.0.1 to 119.249.255.254119.249.255.255131,070
254119.250.0.0/15119.250.0.1 to 119.251.255.254119.251.255.255131,070
255119.252.0.0/15119.252.0.1 to 119.253.255.254119.253.255.255131,070
256119.254.0.0/15119.254.0.1 to 119.255.255.254119.255.255.255131,070

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.