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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.

Network174.0.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
174.0.0.0
Broadcast address
174.3.255.255
First usable
174.0.0.1
Last usable
174.3.255.254
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
Public public
Old class
B (default /16)
As numbers
Hex AE000000 · Integer 2919235584 to 2919497727
Reverse DNS zones
0.174.in-addr.arpa
1.174.in-addr.arpa
2.174.in-addr.arpa
3.174.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
Address10101110.00000000.00000000.00000000174.0.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10101110.00000000.00000000.00000000174.0.0.0
Broadcast10101110.00000011.11111111.11111111174.3.255.255
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)

174.0.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1174.0.0.0/23174.0.0.1 to 174.0.1.254174.0.1.255510
2174.0.2.0/23174.0.2.1 to 174.0.3.254174.0.3.255510
3174.0.4.0/23174.0.4.1 to 174.0.5.254174.0.5.255510
4174.0.6.0/23174.0.6.1 to 174.0.7.254174.0.7.255510
5174.0.8.0/23174.0.8.1 to 174.0.9.254174.0.9.255510
6174.0.10.0/23174.0.10.1 to 174.0.11.254174.0.11.255510
7174.0.12.0/23174.0.12.1 to 174.0.13.254174.0.13.255510
8174.0.14.0/23174.0.14.1 to 174.0.15.254174.0.15.255510
9174.0.16.0/23174.0.16.1 to 174.0.17.254174.0.17.255510
10174.0.18.0/23174.0.18.1 to 174.0.19.254174.0.19.255510
11174.0.20.0/23174.0.20.1 to 174.0.21.254174.0.21.255510
12174.0.22.0/23174.0.22.1 to 174.0.23.254174.0.23.255510
13174.0.24.0/23174.0.24.1 to 174.0.25.254174.0.25.255510
14174.0.26.0/23174.0.26.1 to 174.0.27.254174.0.27.255510
15174.0.28.0/23174.0.28.1 to 174.0.29.254174.0.29.255510
16174.0.30.0/23174.0.30.1 to 174.0.31.254174.0.31.255510
17174.0.32.0/23174.0.32.1 to 174.0.33.254174.0.33.255510
18174.0.34.0/23174.0.34.1 to 174.0.35.254174.0.35.255510
19174.0.36.0/23174.0.36.1 to 174.0.37.254174.0.37.255510
20174.0.38.0/23174.0.38.1 to 174.0.39.254174.0.39.255510
21174.0.40.0/23174.0.40.1 to 174.0.41.254174.0.41.255510
22174.0.42.0/23174.0.42.1 to 174.0.43.254174.0.43.255510
23174.0.44.0/23174.0.44.1 to 174.0.45.254174.0.45.255510
24174.0.46.0/23174.0.46.1 to 174.0.47.254174.0.47.255510
25174.0.48.0/23174.0.48.1 to 174.0.49.254174.0.49.255510
26174.0.50.0/23174.0.50.1 to 174.0.51.254174.0.51.255510
27174.0.52.0/23174.0.52.1 to 174.0.53.254174.0.53.255510
28174.0.54.0/23174.0.54.1 to 174.0.55.254174.0.55.255510
29174.0.56.0/23174.0.56.1 to 174.0.57.254174.0.57.255510
30174.0.58.0/23174.0.58.1 to 174.0.59.254174.0.59.255510
31174.0.60.0/23174.0.60.1 to 174.0.61.254174.0.61.255510
32174.0.62.0/23174.0.62.1 to 174.0.63.254174.0.63.255510
33174.0.64.0/23174.0.64.1 to 174.0.65.254174.0.65.255510
34174.0.66.0/23174.0.66.1 to 174.0.67.254174.0.67.255510
35174.0.68.0/23174.0.68.1 to 174.0.69.254174.0.69.255510
36174.0.70.0/23174.0.70.1 to 174.0.71.254174.0.71.255510
37174.0.72.0/23174.0.72.1 to 174.0.73.254174.0.73.255510
38174.0.74.0/23174.0.74.1 to 174.0.75.254174.0.75.255510
39174.0.76.0/23174.0.76.1 to 174.0.77.254174.0.77.255510
40174.0.78.0/23174.0.78.1 to 174.0.79.254174.0.79.255510
41174.0.80.0/23174.0.80.1 to 174.0.81.254174.0.81.255510
42174.0.82.0/23174.0.82.1 to 174.0.83.254174.0.83.255510
43174.0.84.0/23174.0.84.1 to 174.0.85.254174.0.85.255510
44174.0.86.0/23174.0.86.1 to 174.0.87.254174.0.87.255510
45174.0.88.0/23174.0.88.1 to 174.0.89.254174.0.89.255510
46174.0.90.0/23174.0.90.1 to 174.0.91.254174.0.91.255510
47174.0.92.0/23174.0.92.1 to 174.0.93.254174.0.93.255510
48174.0.94.0/23174.0.94.1 to 174.0.95.254174.0.95.255510
49174.0.96.0/23174.0.96.1 to 174.0.97.254174.0.97.255510
50174.0.98.0/23174.0.98.1 to 174.0.99.254174.0.99.255510
51174.0.100.0/23174.0.100.1 to 174.0.101.254174.0.101.255510
52174.0.102.0/23174.0.102.1 to 174.0.103.254174.0.103.255510
53174.0.104.0/23174.0.104.1 to 174.0.105.254174.0.105.255510
54174.0.106.0/23174.0.106.1 to 174.0.107.254174.0.107.255510
55174.0.108.0/23174.0.108.1 to 174.0.109.254174.0.109.255510
56174.0.110.0/23174.0.110.1 to 174.0.111.254174.0.111.255510
57174.0.112.0/23174.0.112.1 to 174.0.113.254174.0.113.255510
58174.0.114.0/23174.0.114.1 to 174.0.115.254174.0.115.255510
59174.0.116.0/23174.0.116.1 to 174.0.117.254174.0.117.255510
60174.0.118.0/23174.0.118.1 to 174.0.119.254174.0.119.255510
61174.0.120.0/23174.0.120.1 to 174.0.121.254174.0.121.255510
62174.0.122.0/23174.0.122.1 to 174.0.123.254174.0.123.255510
63174.0.124.0/23174.0.124.1 to 174.0.125.254174.0.125.255510
64174.0.126.0/23174.0.126.1 to 174.0.127.254174.0.127.255510
65174.0.128.0/23174.0.128.1 to 174.0.129.254174.0.129.255510
66174.0.130.0/23174.0.130.1 to 174.0.131.254174.0.131.255510
67174.0.132.0/23174.0.132.1 to 174.0.133.254174.0.133.255510
68174.0.134.0/23174.0.134.1 to 174.0.135.254174.0.135.255510
69174.0.136.0/23174.0.136.1 to 174.0.137.254174.0.137.255510
70174.0.138.0/23174.0.138.1 to 174.0.139.254174.0.139.255510
71174.0.140.0/23174.0.140.1 to 174.0.141.254174.0.141.255510
72174.0.142.0/23174.0.142.1 to 174.0.143.254174.0.143.255510
73174.0.144.0/23174.0.144.1 to 174.0.145.254174.0.145.255510
74174.0.146.0/23174.0.146.1 to 174.0.147.254174.0.147.255510
75174.0.148.0/23174.0.148.1 to 174.0.149.254174.0.149.255510
76174.0.150.0/23174.0.150.1 to 174.0.151.254174.0.151.255510
77174.0.152.0/23174.0.152.1 to 174.0.153.254174.0.153.255510
78174.0.154.0/23174.0.154.1 to 174.0.155.254174.0.155.255510
79174.0.156.0/23174.0.156.1 to 174.0.157.254174.0.157.255510
80174.0.158.0/23174.0.158.1 to 174.0.159.254174.0.159.255510
81174.0.160.0/23174.0.160.1 to 174.0.161.254174.0.161.255510
82174.0.162.0/23174.0.162.1 to 174.0.163.254174.0.163.255510
83174.0.164.0/23174.0.164.1 to 174.0.165.254174.0.165.255510
84174.0.166.0/23174.0.166.1 to 174.0.167.254174.0.167.255510
85174.0.168.0/23174.0.168.1 to 174.0.169.254174.0.169.255510
86174.0.170.0/23174.0.170.1 to 174.0.171.254174.0.171.255510
87174.0.172.0/23174.0.172.1 to 174.0.173.254174.0.173.255510
88174.0.174.0/23174.0.174.1 to 174.0.175.254174.0.175.255510
89174.0.176.0/23174.0.176.1 to 174.0.177.254174.0.177.255510
90174.0.178.0/23174.0.178.1 to 174.0.179.254174.0.179.255510
91174.0.180.0/23174.0.180.1 to 174.0.181.254174.0.181.255510
92174.0.182.0/23174.0.182.1 to 174.0.183.254174.0.183.255510
93174.0.184.0/23174.0.184.1 to 174.0.185.254174.0.185.255510
94174.0.186.0/23174.0.186.1 to 174.0.187.254174.0.187.255510
95174.0.188.0/23174.0.188.1 to 174.0.189.254174.0.189.255510
96174.0.190.0/23174.0.190.1 to 174.0.191.254174.0.191.255510
97174.0.192.0/23174.0.192.1 to 174.0.193.254174.0.193.255510
98174.0.194.0/23174.0.194.1 to 174.0.195.254174.0.195.255510
99174.0.196.0/23174.0.196.1 to 174.0.197.254174.0.197.255510
100174.0.198.0/23174.0.198.1 to 174.0.199.254174.0.199.255510
101174.0.200.0/23174.0.200.1 to 174.0.201.254174.0.201.255510
102174.0.202.0/23174.0.202.1 to 174.0.203.254174.0.203.255510
103174.0.204.0/23174.0.204.1 to 174.0.205.254174.0.205.255510
104174.0.206.0/23174.0.206.1 to 174.0.207.254174.0.207.255510
105174.0.208.0/23174.0.208.1 to 174.0.209.254174.0.209.255510
106174.0.210.0/23174.0.210.1 to 174.0.211.254174.0.211.255510
107174.0.212.0/23174.0.212.1 to 174.0.213.254174.0.213.255510
108174.0.214.0/23174.0.214.1 to 174.0.215.254174.0.215.255510
109174.0.216.0/23174.0.216.1 to 174.0.217.254174.0.217.255510
110174.0.218.0/23174.0.218.1 to 174.0.219.254174.0.219.255510
111174.0.220.0/23174.0.220.1 to 174.0.221.254174.0.221.255510
112174.0.222.0/23174.0.222.1 to 174.0.223.254174.0.223.255510
113174.0.224.0/23174.0.224.1 to 174.0.225.254174.0.225.255510
114174.0.226.0/23174.0.226.1 to 174.0.227.254174.0.227.255510
115174.0.228.0/23174.0.228.1 to 174.0.229.254174.0.229.255510
116174.0.230.0/23174.0.230.1 to 174.0.231.254174.0.231.255510
117174.0.232.0/23174.0.232.1 to 174.0.233.254174.0.233.255510
118174.0.234.0/23174.0.234.1 to 174.0.235.254174.0.235.255510
119174.0.236.0/23174.0.236.1 to 174.0.237.254174.0.237.255510
120174.0.238.0/23174.0.238.1 to 174.0.239.254174.0.239.255510
121174.0.240.0/23174.0.240.1 to 174.0.241.254174.0.241.255510
122174.0.242.0/23174.0.242.1 to 174.0.243.254174.0.243.255510
123174.0.244.0/23174.0.244.1 to 174.0.245.254174.0.245.255510
124174.0.246.0/23174.0.246.1 to 174.0.247.254174.0.247.255510
125174.0.248.0/23174.0.248.1 to 174.0.249.254174.0.249.255510
126174.0.250.0/23174.0.250.1 to 174.0.251.254174.0.251.255510
127174.0.252.0/23174.0.252.1 to 174.0.253.254174.0.253.255510
128174.0.254.0/23174.0.254.1 to 174.0.255.254174.0.255.255510
129174.1.0.0/23174.1.0.1 to 174.1.1.254174.1.1.255510
130174.1.2.0/23174.1.2.1 to 174.1.3.254174.1.3.255510
131174.1.4.0/23174.1.4.1 to 174.1.5.254174.1.5.255510
132174.1.6.0/23174.1.6.1 to 174.1.7.254174.1.7.255510
133174.1.8.0/23174.1.8.1 to 174.1.9.254174.1.9.255510
134174.1.10.0/23174.1.10.1 to 174.1.11.254174.1.11.255510
135174.1.12.0/23174.1.12.1 to 174.1.13.254174.1.13.255510
136174.1.14.0/23174.1.14.1 to 174.1.15.254174.1.15.255510
137174.1.16.0/23174.1.16.1 to 174.1.17.254174.1.17.255510
138174.1.18.0/23174.1.18.1 to 174.1.19.254174.1.19.255510
139174.1.20.0/23174.1.20.1 to 174.1.21.254174.1.21.255510
140174.1.22.0/23174.1.22.1 to 174.1.23.254174.1.23.255510
141174.1.24.0/23174.1.24.1 to 174.1.25.254174.1.25.255510
142174.1.26.0/23174.1.26.1 to 174.1.27.254174.1.27.255510
143174.1.28.0/23174.1.28.1 to 174.1.29.254174.1.29.255510
144174.1.30.0/23174.1.30.1 to 174.1.31.254174.1.31.255510
145174.1.32.0/23174.1.32.1 to 174.1.33.254174.1.33.255510
146174.1.34.0/23174.1.34.1 to 174.1.35.254174.1.35.255510
147174.1.36.0/23174.1.36.1 to 174.1.37.254174.1.37.255510
148174.1.38.0/23174.1.38.1 to 174.1.39.254174.1.39.255510
149174.1.40.0/23174.1.40.1 to 174.1.41.254174.1.41.255510
150174.1.42.0/23174.1.42.1 to 174.1.43.254174.1.43.255510
151174.1.44.0/23174.1.44.1 to 174.1.45.254174.1.45.255510
152174.1.46.0/23174.1.46.1 to 174.1.47.254174.1.47.255510
153174.1.48.0/23174.1.48.1 to 174.1.49.254174.1.49.255510
154174.1.50.0/23174.1.50.1 to 174.1.51.254174.1.51.255510
155174.1.52.0/23174.1.52.1 to 174.1.53.254174.1.53.255510
156174.1.54.0/23174.1.54.1 to 174.1.55.254174.1.55.255510
157174.1.56.0/23174.1.56.1 to 174.1.57.254174.1.57.255510
158174.1.58.0/23174.1.58.1 to 174.1.59.254174.1.59.255510
159174.1.60.0/23174.1.60.1 to 174.1.61.254174.1.61.255510
160174.1.62.0/23174.1.62.1 to 174.1.63.254174.1.63.255510
161174.1.64.0/23174.1.64.1 to 174.1.65.254174.1.65.255510
162174.1.66.0/23174.1.66.1 to 174.1.67.254174.1.67.255510
163174.1.68.0/23174.1.68.1 to 174.1.69.254174.1.69.255510
164174.1.70.0/23174.1.70.1 to 174.1.71.254174.1.71.255510
165174.1.72.0/23174.1.72.1 to 174.1.73.254174.1.73.255510
166174.1.74.0/23174.1.74.1 to 174.1.75.254174.1.75.255510
167174.1.76.0/23174.1.76.1 to 174.1.77.254174.1.77.255510
168174.1.78.0/23174.1.78.1 to 174.1.79.254174.1.79.255510
169174.1.80.0/23174.1.80.1 to 174.1.81.254174.1.81.255510
170174.1.82.0/23174.1.82.1 to 174.1.83.254174.1.83.255510
171174.1.84.0/23174.1.84.1 to 174.1.85.254174.1.85.255510
172174.1.86.0/23174.1.86.1 to 174.1.87.254174.1.87.255510
173174.1.88.0/23174.1.88.1 to 174.1.89.254174.1.89.255510
174174.1.90.0/23174.1.90.1 to 174.1.91.254174.1.91.255510
175174.1.92.0/23174.1.92.1 to 174.1.93.254174.1.93.255510
176174.1.94.0/23174.1.94.1 to 174.1.95.254174.1.95.255510
177174.1.96.0/23174.1.96.1 to 174.1.97.254174.1.97.255510
178174.1.98.0/23174.1.98.1 to 174.1.99.254174.1.99.255510
179174.1.100.0/23174.1.100.1 to 174.1.101.254174.1.101.255510
180174.1.102.0/23174.1.102.1 to 174.1.103.254174.1.103.255510
181174.1.104.0/23174.1.104.1 to 174.1.105.254174.1.105.255510
182174.1.106.0/23174.1.106.1 to 174.1.107.254174.1.107.255510
183174.1.108.0/23174.1.108.1 to 174.1.109.254174.1.109.255510
184174.1.110.0/23174.1.110.1 to 174.1.111.254174.1.111.255510
185174.1.112.0/23174.1.112.1 to 174.1.113.254174.1.113.255510
186174.1.114.0/23174.1.114.1 to 174.1.115.254174.1.115.255510
187174.1.116.0/23174.1.116.1 to 174.1.117.254174.1.117.255510
188174.1.118.0/23174.1.118.1 to 174.1.119.254174.1.119.255510
189174.1.120.0/23174.1.120.1 to 174.1.121.254174.1.121.255510
190174.1.122.0/23174.1.122.1 to 174.1.123.254174.1.123.255510
191174.1.124.0/23174.1.124.1 to 174.1.125.254174.1.125.255510
192174.1.126.0/23174.1.126.1 to 174.1.127.254174.1.127.255510
193174.1.128.0/23174.1.128.1 to 174.1.129.254174.1.129.255510
194174.1.130.0/23174.1.130.1 to 174.1.131.254174.1.131.255510
195174.1.132.0/23174.1.132.1 to 174.1.133.254174.1.133.255510
196174.1.134.0/23174.1.134.1 to 174.1.135.254174.1.135.255510
197174.1.136.0/23174.1.136.1 to 174.1.137.254174.1.137.255510
198174.1.138.0/23174.1.138.1 to 174.1.139.254174.1.139.255510
199174.1.140.0/23174.1.140.1 to 174.1.141.254174.1.141.255510
200174.1.142.0/23174.1.142.1 to 174.1.143.254174.1.143.255510
201174.1.144.0/23174.1.144.1 to 174.1.145.254174.1.145.255510
202174.1.146.0/23174.1.146.1 to 174.1.147.254174.1.147.255510
203174.1.148.0/23174.1.148.1 to 174.1.149.254174.1.149.255510
204174.1.150.0/23174.1.150.1 to 174.1.151.254174.1.151.255510
205174.1.152.0/23174.1.152.1 to 174.1.153.254174.1.153.255510
206174.1.154.0/23174.1.154.1 to 174.1.155.254174.1.155.255510
207174.1.156.0/23174.1.156.1 to 174.1.157.254174.1.157.255510
208174.1.158.0/23174.1.158.1 to 174.1.159.254174.1.159.255510
209174.1.160.0/23174.1.160.1 to 174.1.161.254174.1.161.255510
210174.1.162.0/23174.1.162.1 to 174.1.163.254174.1.163.255510
211174.1.164.0/23174.1.164.1 to 174.1.165.254174.1.165.255510
212174.1.166.0/23174.1.166.1 to 174.1.167.254174.1.167.255510
213174.1.168.0/23174.1.168.1 to 174.1.169.254174.1.169.255510
214174.1.170.0/23174.1.170.1 to 174.1.171.254174.1.171.255510
215174.1.172.0/23174.1.172.1 to 174.1.173.254174.1.173.255510
216174.1.174.0/23174.1.174.1 to 174.1.175.254174.1.175.255510
217174.1.176.0/23174.1.176.1 to 174.1.177.254174.1.177.255510
218174.1.178.0/23174.1.178.1 to 174.1.179.254174.1.179.255510
219174.1.180.0/23174.1.180.1 to 174.1.181.254174.1.181.255510
220174.1.182.0/23174.1.182.1 to 174.1.183.254174.1.183.255510
221174.1.184.0/23174.1.184.1 to 174.1.185.254174.1.185.255510
222174.1.186.0/23174.1.186.1 to 174.1.187.254174.1.187.255510
223174.1.188.0/23174.1.188.1 to 174.1.189.254174.1.189.255510
224174.1.190.0/23174.1.190.1 to 174.1.191.254174.1.191.255510
225174.1.192.0/23174.1.192.1 to 174.1.193.254174.1.193.255510
226174.1.194.0/23174.1.194.1 to 174.1.195.254174.1.195.255510
227174.1.196.0/23174.1.196.1 to 174.1.197.254174.1.197.255510
228174.1.198.0/23174.1.198.1 to 174.1.199.254174.1.199.255510
229174.1.200.0/23174.1.200.1 to 174.1.201.254174.1.201.255510
230174.1.202.0/23174.1.202.1 to 174.1.203.254174.1.203.255510
231174.1.204.0/23174.1.204.1 to 174.1.205.254174.1.205.255510
232174.1.206.0/23174.1.206.1 to 174.1.207.254174.1.207.255510
233174.1.208.0/23174.1.208.1 to 174.1.209.254174.1.209.255510
234174.1.210.0/23174.1.210.1 to 174.1.211.254174.1.211.255510
235174.1.212.0/23174.1.212.1 to 174.1.213.254174.1.213.255510
236174.1.214.0/23174.1.214.1 to 174.1.215.254174.1.215.255510
237174.1.216.0/23174.1.216.1 to 174.1.217.254174.1.217.255510
238174.1.218.0/23174.1.218.1 to 174.1.219.254174.1.219.255510
239174.1.220.0/23174.1.220.1 to 174.1.221.254174.1.221.255510
240174.1.222.0/23174.1.222.1 to 174.1.223.254174.1.223.255510
241174.1.224.0/23174.1.224.1 to 174.1.225.254174.1.225.255510
242174.1.226.0/23174.1.226.1 to 174.1.227.254174.1.227.255510
243174.1.228.0/23174.1.228.1 to 174.1.229.254174.1.229.255510
244174.1.230.0/23174.1.230.1 to 174.1.231.254174.1.231.255510
245174.1.232.0/23174.1.232.1 to 174.1.233.254174.1.233.255510
246174.1.234.0/23174.1.234.1 to 174.1.235.254174.1.235.255510
247174.1.236.0/23174.1.236.1 to 174.1.237.254174.1.237.255510
248174.1.238.0/23174.1.238.1 to 174.1.239.254174.1.239.255510
249174.1.240.0/23174.1.240.1 to 174.1.241.254174.1.241.255510
250174.1.242.0/23174.1.242.1 to 174.1.243.254174.1.243.255510
251174.1.244.0/23174.1.244.1 to 174.1.245.254174.1.245.255510
252174.1.246.0/23174.1.246.1 to 174.1.247.254174.1.247.255510
253174.1.248.0/23174.1.248.1 to 174.1.249.254174.1.249.255510
254174.1.250.0/23174.1.250.1 to 174.1.251.254174.1.251.255510
255174.1.252.0/23174.1.252.1 to 174.1.253.254174.1.253.255510
256174.1.254.0/23174.1.254.1 to 174.1.255.254174.1.255.255510

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.