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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.

Network211.32.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
211.32.0.0
Broadcast address
211.35.255.255
First usable
211.32.0.1
Last usable
211.35.255.254
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
C (default /24)
As numbers
Hex D3200000 · Integer 3542089728 to 3542351871
Reverse DNS zones
32.211.in-addr.arpa
33.211.in-addr.arpa
34.211.in-addr.arpa
35.211.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
Address11010011.00100000.00000000.00000000211.32.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network11010011.00100000.00000000.00000000211.32.0.0
Broadcast11010011.00100011.11111111.11111111211.35.255.255
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)

211.32.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1211.32.0.0/23211.32.0.1 to 211.32.1.254211.32.1.255510
2211.32.2.0/23211.32.2.1 to 211.32.3.254211.32.3.255510
3211.32.4.0/23211.32.4.1 to 211.32.5.254211.32.5.255510
4211.32.6.0/23211.32.6.1 to 211.32.7.254211.32.7.255510
5211.32.8.0/23211.32.8.1 to 211.32.9.254211.32.9.255510
6211.32.10.0/23211.32.10.1 to 211.32.11.254211.32.11.255510
7211.32.12.0/23211.32.12.1 to 211.32.13.254211.32.13.255510
8211.32.14.0/23211.32.14.1 to 211.32.15.254211.32.15.255510
9211.32.16.0/23211.32.16.1 to 211.32.17.254211.32.17.255510
10211.32.18.0/23211.32.18.1 to 211.32.19.254211.32.19.255510
11211.32.20.0/23211.32.20.1 to 211.32.21.254211.32.21.255510
12211.32.22.0/23211.32.22.1 to 211.32.23.254211.32.23.255510
13211.32.24.0/23211.32.24.1 to 211.32.25.254211.32.25.255510
14211.32.26.0/23211.32.26.1 to 211.32.27.254211.32.27.255510
15211.32.28.0/23211.32.28.1 to 211.32.29.254211.32.29.255510
16211.32.30.0/23211.32.30.1 to 211.32.31.254211.32.31.255510
17211.32.32.0/23211.32.32.1 to 211.32.33.254211.32.33.255510
18211.32.34.0/23211.32.34.1 to 211.32.35.254211.32.35.255510
19211.32.36.0/23211.32.36.1 to 211.32.37.254211.32.37.255510
20211.32.38.0/23211.32.38.1 to 211.32.39.254211.32.39.255510
21211.32.40.0/23211.32.40.1 to 211.32.41.254211.32.41.255510
22211.32.42.0/23211.32.42.1 to 211.32.43.254211.32.43.255510
23211.32.44.0/23211.32.44.1 to 211.32.45.254211.32.45.255510
24211.32.46.0/23211.32.46.1 to 211.32.47.254211.32.47.255510
25211.32.48.0/23211.32.48.1 to 211.32.49.254211.32.49.255510
26211.32.50.0/23211.32.50.1 to 211.32.51.254211.32.51.255510
27211.32.52.0/23211.32.52.1 to 211.32.53.254211.32.53.255510
28211.32.54.0/23211.32.54.1 to 211.32.55.254211.32.55.255510
29211.32.56.0/23211.32.56.1 to 211.32.57.254211.32.57.255510
30211.32.58.0/23211.32.58.1 to 211.32.59.254211.32.59.255510
31211.32.60.0/23211.32.60.1 to 211.32.61.254211.32.61.255510
32211.32.62.0/23211.32.62.1 to 211.32.63.254211.32.63.255510
33211.32.64.0/23211.32.64.1 to 211.32.65.254211.32.65.255510
34211.32.66.0/23211.32.66.1 to 211.32.67.254211.32.67.255510
35211.32.68.0/23211.32.68.1 to 211.32.69.254211.32.69.255510
36211.32.70.0/23211.32.70.1 to 211.32.71.254211.32.71.255510
37211.32.72.0/23211.32.72.1 to 211.32.73.254211.32.73.255510
38211.32.74.0/23211.32.74.1 to 211.32.75.254211.32.75.255510
39211.32.76.0/23211.32.76.1 to 211.32.77.254211.32.77.255510
40211.32.78.0/23211.32.78.1 to 211.32.79.254211.32.79.255510
41211.32.80.0/23211.32.80.1 to 211.32.81.254211.32.81.255510
42211.32.82.0/23211.32.82.1 to 211.32.83.254211.32.83.255510
43211.32.84.0/23211.32.84.1 to 211.32.85.254211.32.85.255510
44211.32.86.0/23211.32.86.1 to 211.32.87.254211.32.87.255510
45211.32.88.0/23211.32.88.1 to 211.32.89.254211.32.89.255510
46211.32.90.0/23211.32.90.1 to 211.32.91.254211.32.91.255510
47211.32.92.0/23211.32.92.1 to 211.32.93.254211.32.93.255510
48211.32.94.0/23211.32.94.1 to 211.32.95.254211.32.95.255510
49211.32.96.0/23211.32.96.1 to 211.32.97.254211.32.97.255510
50211.32.98.0/23211.32.98.1 to 211.32.99.254211.32.99.255510
51211.32.100.0/23211.32.100.1 to 211.32.101.254211.32.101.255510
52211.32.102.0/23211.32.102.1 to 211.32.103.254211.32.103.255510
53211.32.104.0/23211.32.104.1 to 211.32.105.254211.32.105.255510
54211.32.106.0/23211.32.106.1 to 211.32.107.254211.32.107.255510
55211.32.108.0/23211.32.108.1 to 211.32.109.254211.32.109.255510
56211.32.110.0/23211.32.110.1 to 211.32.111.254211.32.111.255510
57211.32.112.0/23211.32.112.1 to 211.32.113.254211.32.113.255510
58211.32.114.0/23211.32.114.1 to 211.32.115.254211.32.115.255510
59211.32.116.0/23211.32.116.1 to 211.32.117.254211.32.117.255510
60211.32.118.0/23211.32.118.1 to 211.32.119.254211.32.119.255510
61211.32.120.0/23211.32.120.1 to 211.32.121.254211.32.121.255510
62211.32.122.0/23211.32.122.1 to 211.32.123.254211.32.123.255510
63211.32.124.0/23211.32.124.1 to 211.32.125.254211.32.125.255510
64211.32.126.0/23211.32.126.1 to 211.32.127.254211.32.127.255510
65211.32.128.0/23211.32.128.1 to 211.32.129.254211.32.129.255510
66211.32.130.0/23211.32.130.1 to 211.32.131.254211.32.131.255510
67211.32.132.0/23211.32.132.1 to 211.32.133.254211.32.133.255510
68211.32.134.0/23211.32.134.1 to 211.32.135.254211.32.135.255510
69211.32.136.0/23211.32.136.1 to 211.32.137.254211.32.137.255510
70211.32.138.0/23211.32.138.1 to 211.32.139.254211.32.139.255510
71211.32.140.0/23211.32.140.1 to 211.32.141.254211.32.141.255510
72211.32.142.0/23211.32.142.1 to 211.32.143.254211.32.143.255510
73211.32.144.0/23211.32.144.1 to 211.32.145.254211.32.145.255510
74211.32.146.0/23211.32.146.1 to 211.32.147.254211.32.147.255510
75211.32.148.0/23211.32.148.1 to 211.32.149.254211.32.149.255510
76211.32.150.0/23211.32.150.1 to 211.32.151.254211.32.151.255510
77211.32.152.0/23211.32.152.1 to 211.32.153.254211.32.153.255510
78211.32.154.0/23211.32.154.1 to 211.32.155.254211.32.155.255510
79211.32.156.0/23211.32.156.1 to 211.32.157.254211.32.157.255510
80211.32.158.0/23211.32.158.1 to 211.32.159.254211.32.159.255510
81211.32.160.0/23211.32.160.1 to 211.32.161.254211.32.161.255510
82211.32.162.0/23211.32.162.1 to 211.32.163.254211.32.163.255510
83211.32.164.0/23211.32.164.1 to 211.32.165.254211.32.165.255510
84211.32.166.0/23211.32.166.1 to 211.32.167.254211.32.167.255510
85211.32.168.0/23211.32.168.1 to 211.32.169.254211.32.169.255510
86211.32.170.0/23211.32.170.1 to 211.32.171.254211.32.171.255510
87211.32.172.0/23211.32.172.1 to 211.32.173.254211.32.173.255510
88211.32.174.0/23211.32.174.1 to 211.32.175.254211.32.175.255510
89211.32.176.0/23211.32.176.1 to 211.32.177.254211.32.177.255510
90211.32.178.0/23211.32.178.1 to 211.32.179.254211.32.179.255510
91211.32.180.0/23211.32.180.1 to 211.32.181.254211.32.181.255510
92211.32.182.0/23211.32.182.1 to 211.32.183.254211.32.183.255510
93211.32.184.0/23211.32.184.1 to 211.32.185.254211.32.185.255510
94211.32.186.0/23211.32.186.1 to 211.32.187.254211.32.187.255510
95211.32.188.0/23211.32.188.1 to 211.32.189.254211.32.189.255510
96211.32.190.0/23211.32.190.1 to 211.32.191.254211.32.191.255510
97211.32.192.0/23211.32.192.1 to 211.32.193.254211.32.193.255510
98211.32.194.0/23211.32.194.1 to 211.32.195.254211.32.195.255510
99211.32.196.0/23211.32.196.1 to 211.32.197.254211.32.197.255510
100211.32.198.0/23211.32.198.1 to 211.32.199.254211.32.199.255510
101211.32.200.0/23211.32.200.1 to 211.32.201.254211.32.201.255510
102211.32.202.0/23211.32.202.1 to 211.32.203.254211.32.203.255510
103211.32.204.0/23211.32.204.1 to 211.32.205.254211.32.205.255510
104211.32.206.0/23211.32.206.1 to 211.32.207.254211.32.207.255510
105211.32.208.0/23211.32.208.1 to 211.32.209.254211.32.209.255510
106211.32.210.0/23211.32.210.1 to 211.32.211.254211.32.211.255510
107211.32.212.0/23211.32.212.1 to 211.32.213.254211.32.213.255510
108211.32.214.0/23211.32.214.1 to 211.32.215.254211.32.215.255510
109211.32.216.0/23211.32.216.1 to 211.32.217.254211.32.217.255510
110211.32.218.0/23211.32.218.1 to 211.32.219.254211.32.219.255510
111211.32.220.0/23211.32.220.1 to 211.32.221.254211.32.221.255510
112211.32.222.0/23211.32.222.1 to 211.32.223.254211.32.223.255510
113211.32.224.0/23211.32.224.1 to 211.32.225.254211.32.225.255510
114211.32.226.0/23211.32.226.1 to 211.32.227.254211.32.227.255510
115211.32.228.0/23211.32.228.1 to 211.32.229.254211.32.229.255510
116211.32.230.0/23211.32.230.1 to 211.32.231.254211.32.231.255510
117211.32.232.0/23211.32.232.1 to 211.32.233.254211.32.233.255510
118211.32.234.0/23211.32.234.1 to 211.32.235.254211.32.235.255510
119211.32.236.0/23211.32.236.1 to 211.32.237.254211.32.237.255510
120211.32.238.0/23211.32.238.1 to 211.32.239.254211.32.239.255510
121211.32.240.0/23211.32.240.1 to 211.32.241.254211.32.241.255510
122211.32.242.0/23211.32.242.1 to 211.32.243.254211.32.243.255510
123211.32.244.0/23211.32.244.1 to 211.32.245.254211.32.245.255510
124211.32.246.0/23211.32.246.1 to 211.32.247.254211.32.247.255510
125211.32.248.0/23211.32.248.1 to 211.32.249.254211.32.249.255510
126211.32.250.0/23211.32.250.1 to 211.32.251.254211.32.251.255510
127211.32.252.0/23211.32.252.1 to 211.32.253.254211.32.253.255510
128211.32.254.0/23211.32.254.1 to 211.32.255.254211.32.255.255510
129211.33.0.0/23211.33.0.1 to 211.33.1.254211.33.1.255510
130211.33.2.0/23211.33.2.1 to 211.33.3.254211.33.3.255510
131211.33.4.0/23211.33.4.1 to 211.33.5.254211.33.5.255510
132211.33.6.0/23211.33.6.1 to 211.33.7.254211.33.7.255510
133211.33.8.0/23211.33.8.1 to 211.33.9.254211.33.9.255510
134211.33.10.0/23211.33.10.1 to 211.33.11.254211.33.11.255510
135211.33.12.0/23211.33.12.1 to 211.33.13.254211.33.13.255510
136211.33.14.0/23211.33.14.1 to 211.33.15.254211.33.15.255510
137211.33.16.0/23211.33.16.1 to 211.33.17.254211.33.17.255510
138211.33.18.0/23211.33.18.1 to 211.33.19.254211.33.19.255510
139211.33.20.0/23211.33.20.1 to 211.33.21.254211.33.21.255510
140211.33.22.0/23211.33.22.1 to 211.33.23.254211.33.23.255510
141211.33.24.0/23211.33.24.1 to 211.33.25.254211.33.25.255510
142211.33.26.0/23211.33.26.1 to 211.33.27.254211.33.27.255510
143211.33.28.0/23211.33.28.1 to 211.33.29.254211.33.29.255510
144211.33.30.0/23211.33.30.1 to 211.33.31.254211.33.31.255510
145211.33.32.0/23211.33.32.1 to 211.33.33.254211.33.33.255510
146211.33.34.0/23211.33.34.1 to 211.33.35.254211.33.35.255510
147211.33.36.0/23211.33.36.1 to 211.33.37.254211.33.37.255510
148211.33.38.0/23211.33.38.1 to 211.33.39.254211.33.39.255510
149211.33.40.0/23211.33.40.1 to 211.33.41.254211.33.41.255510
150211.33.42.0/23211.33.42.1 to 211.33.43.254211.33.43.255510
151211.33.44.0/23211.33.44.1 to 211.33.45.254211.33.45.255510
152211.33.46.0/23211.33.46.1 to 211.33.47.254211.33.47.255510
153211.33.48.0/23211.33.48.1 to 211.33.49.254211.33.49.255510
154211.33.50.0/23211.33.50.1 to 211.33.51.254211.33.51.255510
155211.33.52.0/23211.33.52.1 to 211.33.53.254211.33.53.255510
156211.33.54.0/23211.33.54.1 to 211.33.55.254211.33.55.255510
157211.33.56.0/23211.33.56.1 to 211.33.57.254211.33.57.255510
158211.33.58.0/23211.33.58.1 to 211.33.59.254211.33.59.255510
159211.33.60.0/23211.33.60.1 to 211.33.61.254211.33.61.255510
160211.33.62.0/23211.33.62.1 to 211.33.63.254211.33.63.255510
161211.33.64.0/23211.33.64.1 to 211.33.65.254211.33.65.255510
162211.33.66.0/23211.33.66.1 to 211.33.67.254211.33.67.255510
163211.33.68.0/23211.33.68.1 to 211.33.69.254211.33.69.255510
164211.33.70.0/23211.33.70.1 to 211.33.71.254211.33.71.255510
165211.33.72.0/23211.33.72.1 to 211.33.73.254211.33.73.255510
166211.33.74.0/23211.33.74.1 to 211.33.75.254211.33.75.255510
167211.33.76.0/23211.33.76.1 to 211.33.77.254211.33.77.255510
168211.33.78.0/23211.33.78.1 to 211.33.79.254211.33.79.255510
169211.33.80.0/23211.33.80.1 to 211.33.81.254211.33.81.255510
170211.33.82.0/23211.33.82.1 to 211.33.83.254211.33.83.255510
171211.33.84.0/23211.33.84.1 to 211.33.85.254211.33.85.255510
172211.33.86.0/23211.33.86.1 to 211.33.87.254211.33.87.255510
173211.33.88.0/23211.33.88.1 to 211.33.89.254211.33.89.255510
174211.33.90.0/23211.33.90.1 to 211.33.91.254211.33.91.255510
175211.33.92.0/23211.33.92.1 to 211.33.93.254211.33.93.255510
176211.33.94.0/23211.33.94.1 to 211.33.95.254211.33.95.255510
177211.33.96.0/23211.33.96.1 to 211.33.97.254211.33.97.255510
178211.33.98.0/23211.33.98.1 to 211.33.99.254211.33.99.255510
179211.33.100.0/23211.33.100.1 to 211.33.101.254211.33.101.255510
180211.33.102.0/23211.33.102.1 to 211.33.103.254211.33.103.255510
181211.33.104.0/23211.33.104.1 to 211.33.105.254211.33.105.255510
182211.33.106.0/23211.33.106.1 to 211.33.107.254211.33.107.255510
183211.33.108.0/23211.33.108.1 to 211.33.109.254211.33.109.255510
184211.33.110.0/23211.33.110.1 to 211.33.111.254211.33.111.255510
185211.33.112.0/23211.33.112.1 to 211.33.113.254211.33.113.255510
186211.33.114.0/23211.33.114.1 to 211.33.115.254211.33.115.255510
187211.33.116.0/23211.33.116.1 to 211.33.117.254211.33.117.255510
188211.33.118.0/23211.33.118.1 to 211.33.119.254211.33.119.255510
189211.33.120.0/23211.33.120.1 to 211.33.121.254211.33.121.255510
190211.33.122.0/23211.33.122.1 to 211.33.123.254211.33.123.255510
191211.33.124.0/23211.33.124.1 to 211.33.125.254211.33.125.255510
192211.33.126.0/23211.33.126.1 to 211.33.127.254211.33.127.255510
193211.33.128.0/23211.33.128.1 to 211.33.129.254211.33.129.255510
194211.33.130.0/23211.33.130.1 to 211.33.131.254211.33.131.255510
195211.33.132.0/23211.33.132.1 to 211.33.133.254211.33.133.255510
196211.33.134.0/23211.33.134.1 to 211.33.135.254211.33.135.255510
197211.33.136.0/23211.33.136.1 to 211.33.137.254211.33.137.255510
198211.33.138.0/23211.33.138.1 to 211.33.139.254211.33.139.255510
199211.33.140.0/23211.33.140.1 to 211.33.141.254211.33.141.255510
200211.33.142.0/23211.33.142.1 to 211.33.143.254211.33.143.255510
201211.33.144.0/23211.33.144.1 to 211.33.145.254211.33.145.255510
202211.33.146.0/23211.33.146.1 to 211.33.147.254211.33.147.255510
203211.33.148.0/23211.33.148.1 to 211.33.149.254211.33.149.255510
204211.33.150.0/23211.33.150.1 to 211.33.151.254211.33.151.255510
205211.33.152.0/23211.33.152.1 to 211.33.153.254211.33.153.255510
206211.33.154.0/23211.33.154.1 to 211.33.155.254211.33.155.255510
207211.33.156.0/23211.33.156.1 to 211.33.157.254211.33.157.255510
208211.33.158.0/23211.33.158.1 to 211.33.159.254211.33.159.255510
209211.33.160.0/23211.33.160.1 to 211.33.161.254211.33.161.255510
210211.33.162.0/23211.33.162.1 to 211.33.163.254211.33.163.255510
211211.33.164.0/23211.33.164.1 to 211.33.165.254211.33.165.255510
212211.33.166.0/23211.33.166.1 to 211.33.167.254211.33.167.255510
213211.33.168.0/23211.33.168.1 to 211.33.169.254211.33.169.255510
214211.33.170.0/23211.33.170.1 to 211.33.171.254211.33.171.255510
215211.33.172.0/23211.33.172.1 to 211.33.173.254211.33.173.255510
216211.33.174.0/23211.33.174.1 to 211.33.175.254211.33.175.255510
217211.33.176.0/23211.33.176.1 to 211.33.177.254211.33.177.255510
218211.33.178.0/23211.33.178.1 to 211.33.179.254211.33.179.255510
219211.33.180.0/23211.33.180.1 to 211.33.181.254211.33.181.255510
220211.33.182.0/23211.33.182.1 to 211.33.183.254211.33.183.255510
221211.33.184.0/23211.33.184.1 to 211.33.185.254211.33.185.255510
222211.33.186.0/23211.33.186.1 to 211.33.187.254211.33.187.255510
223211.33.188.0/23211.33.188.1 to 211.33.189.254211.33.189.255510
224211.33.190.0/23211.33.190.1 to 211.33.191.254211.33.191.255510
225211.33.192.0/23211.33.192.1 to 211.33.193.254211.33.193.255510
226211.33.194.0/23211.33.194.1 to 211.33.195.254211.33.195.255510
227211.33.196.0/23211.33.196.1 to 211.33.197.254211.33.197.255510
228211.33.198.0/23211.33.198.1 to 211.33.199.254211.33.199.255510
229211.33.200.0/23211.33.200.1 to 211.33.201.254211.33.201.255510
230211.33.202.0/23211.33.202.1 to 211.33.203.254211.33.203.255510
231211.33.204.0/23211.33.204.1 to 211.33.205.254211.33.205.255510
232211.33.206.0/23211.33.206.1 to 211.33.207.254211.33.207.255510
233211.33.208.0/23211.33.208.1 to 211.33.209.254211.33.209.255510
234211.33.210.0/23211.33.210.1 to 211.33.211.254211.33.211.255510
235211.33.212.0/23211.33.212.1 to 211.33.213.254211.33.213.255510
236211.33.214.0/23211.33.214.1 to 211.33.215.254211.33.215.255510
237211.33.216.0/23211.33.216.1 to 211.33.217.254211.33.217.255510
238211.33.218.0/23211.33.218.1 to 211.33.219.254211.33.219.255510
239211.33.220.0/23211.33.220.1 to 211.33.221.254211.33.221.255510
240211.33.222.0/23211.33.222.1 to 211.33.223.254211.33.223.255510
241211.33.224.0/23211.33.224.1 to 211.33.225.254211.33.225.255510
242211.33.226.0/23211.33.226.1 to 211.33.227.254211.33.227.255510
243211.33.228.0/23211.33.228.1 to 211.33.229.254211.33.229.255510
244211.33.230.0/23211.33.230.1 to 211.33.231.254211.33.231.255510
245211.33.232.0/23211.33.232.1 to 211.33.233.254211.33.233.255510
246211.33.234.0/23211.33.234.1 to 211.33.235.254211.33.235.255510
247211.33.236.0/23211.33.236.1 to 211.33.237.254211.33.237.255510
248211.33.238.0/23211.33.238.1 to 211.33.239.254211.33.239.255510
249211.33.240.0/23211.33.240.1 to 211.33.241.254211.33.241.255510
250211.33.242.0/23211.33.242.1 to 211.33.243.254211.33.243.255510
251211.33.244.0/23211.33.244.1 to 211.33.245.254211.33.245.255510
252211.33.246.0/23211.33.246.1 to 211.33.247.254211.33.247.255510
253211.33.248.0/23211.33.248.1 to 211.33.249.254211.33.249.255510
254211.33.250.0/23211.33.250.1 to 211.33.251.254211.33.251.255510
255211.33.252.0/23211.33.252.1 to 211.33.253.254211.33.253.255510
256211.33.254.0/23211.33.254.1 to 211.33.255.254211.33.255.255510

IPv4 CIDR reference (/0 to /32)

IPv4 prefix lengths
PrefixSubnet maskWildcardAddressesUsable hostsSizeTypical use
/00.0.0.0255.255.255.2554,294,967,2964,294,967,29416,777,216 × /24
/1128.0.0.0127.255.255.2552,147,483,6482,147,483,6468,388,608 × /24
/2192.0.0.063.255.255.2551,073,741,8241,073,741,8224,194,304 × /24
/3224.0.0.031.255.255.255536,870,912536,870,9102,097,152 × /24
/4240.0.0.015.255.255.255268,435,456268,435,4541,048,576 × /24
/5248.0.0.07.255.255.255134,217,728134,217,726524,288 × /24
/6252.0.0.03.255.255.25567,108,86467,108,862262,144 × /24
/7254.0.0.01.255.255.25533,554,43233,554,430131,072 × /24
/8255.0.0.00.255.255.25516,777,21616,777,21465,536 × /24Old class A; 10.0.0.0/8
/9255.128.0.00.127.255.2558,388,6088,388,60632,768 × /24
/10255.192.0.00.63.255.2554,194,3044,194,30216,384 × /24
/11255.224.0.00.31.255.2552,097,1522,097,1508,192 × /24
/12255.240.0.00.15.255.2551,048,5761,048,5744,096 × /24172.16.0.0/12
/13255.248.0.00.7.255.255524,288524,2862,048 × /24
/14255.252.0.00.3.255.255262,144262,1421,024 × /24
/15255.254.0.00.1.255.255131,072131,070512 × /24
/16255.255.0.00.0.255.25565,53665,534256 × /24Old class B; 192.168.0.0/16
/17255.255.128.00.0.127.25532,76832,766128 × /24
/18255.255.192.00.0.63.25516,38416,38264 × /24
/19255.255.224.00.0.31.2558,1928,19032 × /24
/20255.255.240.00.0.15.2554,0964,09416 × /24
/21255.255.248.00.0.7.2552,0482,0468 × /24
/22255.255.252.00.0.3.2551,0241,0224 × /24Large office or guest Wi-Fi (1,022 hosts)
/23255.255.254.00.0.1.2555125102 × /24Larger office LAN (510 hosts)
/24255.255.255.00.0.0.2552562541 × /24Typical office LAN (old class C)
/25255.255.255.1280.0.0.1271281261/2 of a /24Smaller LAN or VLAN
/26255.255.255.1920.0.0.6364621/4 of a /24Smaller LAN or VLAN
/27255.255.255.2240.0.0.3132301/8 of a /24Small VLAN, phones, cameras
/28255.255.255.2400.0.0.1516141/16 of a /24Small VLAN, phones, cameras
/29255.255.255.2480.0.0.7861/32 of a /24Small fixed public block (5 usable)
/30255.255.255.2520.0.0.3421/64 of a /24Point-to-point (old style)
/31255.255.255.2540.0.0.1221/128 of a /24Point-to-point link (RFC 3021)
/32255.255.255.2550.0.0.0111/256 of a /24One host

IPv6 prefix reference

IPv6 prefix lengths
PrefixAddresses/64 LANs/48 sitesNibbleTypical use
/342,535,295,865,117,307,932,921,825,928,971,026,432 (2^125)2,305,843,009,213,693,95235,184,372,088,832NoAll global unicast (2000::/3)
/165,192,296,858,534,827,628,530,496,329,220,096 (2^112)281,474,976,710,6564,294,967,296Yes
/20324,518,553,658,426,726,783,156,020,576,256 (2^108)17,592,186,044,416268,435,456YesLarge provider allocation (RIPE minimum for some)
/29633,825,300,114,114,700,748,351,602,688 (2^99)34,359,738,368524,288NoRIPE allocation to a provider (often)
/3279,228,162,514,264,337,593,543,950,336 (2^96)4,294,967,29665,536YesProvider allocation (RIPE default)
/364,951,760,157,141,521,099,596,496,896 (2^92)268,435,4564,096Yes
/40309,485,009,821,345,068,724,781,056 (2^88)16,777,216256Yes
/4419,342,813,113,834,066,795,298,816 (2^84)1,048,57616Yes
/481,208,925,819,614,629,174,706,176 (2^80)65,5361YesOne site or organisation (RIPE PI / assignment)
/5275,557,863,725,914,323,419,136 (2^76)4,096Yes
/564,722,366,482,869,645,213,696 (2^72)256YesSmall site or home (common provider assignment)
/60295,147,905,179,352,825,856 (2^68)16YesSome home broadband (16 LANs)
/6418,446,744,073,709,551,616 (2^64)1YesOne LAN or VLAN (needed for SLAAC)
/7272,057,594,037,927,936 (2^56)1/256 of a /64Yes
/80281,474,976,710,656 (2^48)1/65,536 of a /64Yes
/964,294,967,2961/4,294,967,296 of a /64YesEmbeds an IPv4 address (NAT64)
/11265,5361/281,474,976,710,656 of a /64Yes
/1202561/72,057,594,037,927,936 of a /64Yes
/124161/1,152,921,504,606,846,976 of a /64Yes
/12641/4,611,686,018,427,387,904 of a /64No
/12721/9,223,372,036,854,775,808 of a /64NoPoint-to-point link (RFC 6164)
/12811/18,446,744,073,709,551,616 of a /64YesOne host or loopback

Private and special ranges

IPv4

Special-purpose ranges
RangeNameWhat it is
255.255.255.255/32Limited broadcastEvery host on the local network
0.0.0.0/8This networkNot routed; 0.0.0.0 means "any address" in settings
10.0.0.0/8Private (RFC 1918)Office and home networks; not routed on the internet
100.64.0.0/10Shared address space (CGNAT)Used by providers behind carrier-grade NAT (RFC 6598)
127.0.0.0/8LoopbackThis computer
169.254.0.0/16Link-local (APIPA)Self-assigned when no DHCP server answers
172.16.0.0/12Private (RFC 1918)Office and home networks; not routed on the internet
192.0.0.0/24IETF protocol assignmentsSpecial uses such as DS-Lite
192.0.2.0/24Documentation (TEST-NET-1)For examples; never used on a network
192.88.99.0/246to4 relay (deprecated)Formerly anycast for 6to4
192.168.0.0/16Private (RFC 1918)Office and home networks; not routed on the internet
198.18.0.0/15BenchmarkingNetwork equipment testing (RFC 2544)
198.51.100.0/24Documentation (TEST-NET-2)For examples; never used on a network
203.0.113.0/24Documentation (TEST-NET-3)For examples; never used on a network
224.0.0.0/4MulticastOne-to-many traffic, such as IPTV and routing protocols
240.0.0.0/4ReservedFuture use; not usable on most systems

IPv6

Special-purpose ranges
RangeNameWhat it is
::/128UnspecifiedNo address; :: means "any address" in settings
::1/128LoopbackThis computer
::ffff:0:0/96IPv4-mappedAn IPv4 address written as IPv6
64:ff9b::/96NAT64IPv4 addresses reached through a NAT64 gateway
100::/64Discard onlyTraffic sent here is dropped (RFC 6666)
2001:db8::/32DocumentationFor examples; never used on a network
2001::/32TeredoIPv6 tunnelled over IPv4 UDP
2002::/166to4IPv6 tunnelled over IPv4 (largely retired)
3fff::/20DocumentationFor examples (RFC 9637)
fc00::/7Unique local (ULA)Private IPv6, like RFC 1918; usually fd00::/8
fe80::/10Link-localEvery IPv6 interface has one; not routed
ff00::/8MulticastOne-to-many traffic; replaces broadcast
2000::/3Global unicastPublic internet addresses

About this tool

A network is written as an address and a prefix length, such as 192.168.1.0/24: the first 24 bits name the network and the rest number the devices on it. The calculator works out where the network starts and ends, how many devices it holds, its subnet and wildcard masks, and the reverse DNS zone to ask your provider for.

It also splits a network into equal smaller ones (one per VLAN or site), turns a range of addresses into the fewest CIDR blocks for a firewall rule, and lists every IPv4 prefix length and the common IPv6 ones in reference tables.

Common questions

Why are two addresses lost in every IPv4 subnet?

The first address names the network and the last is the broadcast address, so a /24 has 256 addresses but 254 for devices. A /31 (a link between two routers) and a /32 (one host) are the exceptions.

What size of IPv6 network should a LAN use?

Always /64. Devices pick their own address within it (SLAAC), which needs the full 64 bits. A site usually gets a /48 or /56 from its provider, which holds 65,536 or 256 LANs.

What is a wildcard mask?

The subnet mask turned inside out: 255.255.255.0 becomes 0.0.0.255. Cisco access lists and OSPF use it to say which bits must match.

Which ranges can I use inside an office?

IPv4: 10.0.0.0/8, 172.16.0.0/12 and 192.168.0.0/16. IPv6: unique local addresses from fd00::/8, though most networks use the public prefix from their provider.