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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.

Network211.40.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
211.40.0.0
Broadcast address
211.43.255.255
First usable
211.40.0.1
Last usable
211.43.255.254
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 D3280000 · Integer 3542614016 to 3542876159
Reverse DNS zones
40.211.in-addr.arpa
41.211.in-addr.arpa
42.211.in-addr.arpa
43.211.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
Address11010011.00101000.00000000.00000000211.40.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network11010011.00101000.00000000.00000000211.40.0.0
Broadcast11010011.00101011.11111111.11111111211.43.255.255
Split into smaller subnets/24
/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)

211.40.0.0/14 makes 1,024 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1211.40.0.0/24211.40.0.1 to 211.40.0.254211.40.0.255254
2211.40.1.0/24211.40.1.1 to 211.40.1.254211.40.1.255254
3211.40.2.0/24211.40.2.1 to 211.40.2.254211.40.2.255254
4211.40.3.0/24211.40.3.1 to 211.40.3.254211.40.3.255254
5211.40.4.0/24211.40.4.1 to 211.40.4.254211.40.4.255254
6211.40.5.0/24211.40.5.1 to 211.40.5.254211.40.5.255254
7211.40.6.0/24211.40.6.1 to 211.40.6.254211.40.6.255254
8211.40.7.0/24211.40.7.1 to 211.40.7.254211.40.7.255254
9211.40.8.0/24211.40.8.1 to 211.40.8.254211.40.8.255254
10211.40.9.0/24211.40.9.1 to 211.40.9.254211.40.9.255254
11211.40.10.0/24211.40.10.1 to 211.40.10.254211.40.10.255254
12211.40.11.0/24211.40.11.1 to 211.40.11.254211.40.11.255254
13211.40.12.0/24211.40.12.1 to 211.40.12.254211.40.12.255254
14211.40.13.0/24211.40.13.1 to 211.40.13.254211.40.13.255254
15211.40.14.0/24211.40.14.1 to 211.40.14.254211.40.14.255254
16211.40.15.0/24211.40.15.1 to 211.40.15.254211.40.15.255254
17211.40.16.0/24211.40.16.1 to 211.40.16.254211.40.16.255254
18211.40.17.0/24211.40.17.1 to 211.40.17.254211.40.17.255254
19211.40.18.0/24211.40.18.1 to 211.40.18.254211.40.18.255254
20211.40.19.0/24211.40.19.1 to 211.40.19.254211.40.19.255254
21211.40.20.0/24211.40.20.1 to 211.40.20.254211.40.20.255254
22211.40.21.0/24211.40.21.1 to 211.40.21.254211.40.21.255254
23211.40.22.0/24211.40.22.1 to 211.40.22.254211.40.22.255254
24211.40.23.0/24211.40.23.1 to 211.40.23.254211.40.23.255254
25211.40.24.0/24211.40.24.1 to 211.40.24.254211.40.24.255254
26211.40.25.0/24211.40.25.1 to 211.40.25.254211.40.25.255254
27211.40.26.0/24211.40.26.1 to 211.40.26.254211.40.26.255254
28211.40.27.0/24211.40.27.1 to 211.40.27.254211.40.27.255254
29211.40.28.0/24211.40.28.1 to 211.40.28.254211.40.28.255254
30211.40.29.0/24211.40.29.1 to 211.40.29.254211.40.29.255254
31211.40.30.0/24211.40.30.1 to 211.40.30.254211.40.30.255254
32211.40.31.0/24211.40.31.1 to 211.40.31.254211.40.31.255254
33211.40.32.0/24211.40.32.1 to 211.40.32.254211.40.32.255254
34211.40.33.0/24211.40.33.1 to 211.40.33.254211.40.33.255254
35211.40.34.0/24211.40.34.1 to 211.40.34.254211.40.34.255254
36211.40.35.0/24211.40.35.1 to 211.40.35.254211.40.35.255254
37211.40.36.0/24211.40.36.1 to 211.40.36.254211.40.36.255254
38211.40.37.0/24211.40.37.1 to 211.40.37.254211.40.37.255254
39211.40.38.0/24211.40.38.1 to 211.40.38.254211.40.38.255254
40211.40.39.0/24211.40.39.1 to 211.40.39.254211.40.39.255254
41211.40.40.0/24211.40.40.1 to 211.40.40.254211.40.40.255254
42211.40.41.0/24211.40.41.1 to 211.40.41.254211.40.41.255254
43211.40.42.0/24211.40.42.1 to 211.40.42.254211.40.42.255254
44211.40.43.0/24211.40.43.1 to 211.40.43.254211.40.43.255254
45211.40.44.0/24211.40.44.1 to 211.40.44.254211.40.44.255254
46211.40.45.0/24211.40.45.1 to 211.40.45.254211.40.45.255254
47211.40.46.0/24211.40.46.1 to 211.40.46.254211.40.46.255254
48211.40.47.0/24211.40.47.1 to 211.40.47.254211.40.47.255254
49211.40.48.0/24211.40.48.1 to 211.40.48.254211.40.48.255254
50211.40.49.0/24211.40.49.1 to 211.40.49.254211.40.49.255254
51211.40.50.0/24211.40.50.1 to 211.40.50.254211.40.50.255254
52211.40.51.0/24211.40.51.1 to 211.40.51.254211.40.51.255254
53211.40.52.0/24211.40.52.1 to 211.40.52.254211.40.52.255254
54211.40.53.0/24211.40.53.1 to 211.40.53.254211.40.53.255254
55211.40.54.0/24211.40.54.1 to 211.40.54.254211.40.54.255254
56211.40.55.0/24211.40.55.1 to 211.40.55.254211.40.55.255254
57211.40.56.0/24211.40.56.1 to 211.40.56.254211.40.56.255254
58211.40.57.0/24211.40.57.1 to 211.40.57.254211.40.57.255254
59211.40.58.0/24211.40.58.1 to 211.40.58.254211.40.58.255254
60211.40.59.0/24211.40.59.1 to 211.40.59.254211.40.59.255254
61211.40.60.0/24211.40.60.1 to 211.40.60.254211.40.60.255254
62211.40.61.0/24211.40.61.1 to 211.40.61.254211.40.61.255254
63211.40.62.0/24211.40.62.1 to 211.40.62.254211.40.62.255254
64211.40.63.0/24211.40.63.1 to 211.40.63.254211.40.63.255254
65211.40.64.0/24211.40.64.1 to 211.40.64.254211.40.64.255254
66211.40.65.0/24211.40.65.1 to 211.40.65.254211.40.65.255254
67211.40.66.0/24211.40.66.1 to 211.40.66.254211.40.66.255254
68211.40.67.0/24211.40.67.1 to 211.40.67.254211.40.67.255254
69211.40.68.0/24211.40.68.1 to 211.40.68.254211.40.68.255254
70211.40.69.0/24211.40.69.1 to 211.40.69.254211.40.69.255254
71211.40.70.0/24211.40.70.1 to 211.40.70.254211.40.70.255254
72211.40.71.0/24211.40.71.1 to 211.40.71.254211.40.71.255254
73211.40.72.0/24211.40.72.1 to 211.40.72.254211.40.72.255254
74211.40.73.0/24211.40.73.1 to 211.40.73.254211.40.73.255254
75211.40.74.0/24211.40.74.1 to 211.40.74.254211.40.74.255254
76211.40.75.0/24211.40.75.1 to 211.40.75.254211.40.75.255254
77211.40.76.0/24211.40.76.1 to 211.40.76.254211.40.76.255254
78211.40.77.0/24211.40.77.1 to 211.40.77.254211.40.77.255254
79211.40.78.0/24211.40.78.1 to 211.40.78.254211.40.78.255254
80211.40.79.0/24211.40.79.1 to 211.40.79.254211.40.79.255254
81211.40.80.0/24211.40.80.1 to 211.40.80.254211.40.80.255254
82211.40.81.0/24211.40.81.1 to 211.40.81.254211.40.81.255254
83211.40.82.0/24211.40.82.1 to 211.40.82.254211.40.82.255254
84211.40.83.0/24211.40.83.1 to 211.40.83.254211.40.83.255254
85211.40.84.0/24211.40.84.1 to 211.40.84.254211.40.84.255254
86211.40.85.0/24211.40.85.1 to 211.40.85.254211.40.85.255254
87211.40.86.0/24211.40.86.1 to 211.40.86.254211.40.86.255254
88211.40.87.0/24211.40.87.1 to 211.40.87.254211.40.87.255254
89211.40.88.0/24211.40.88.1 to 211.40.88.254211.40.88.255254
90211.40.89.0/24211.40.89.1 to 211.40.89.254211.40.89.255254
91211.40.90.0/24211.40.90.1 to 211.40.90.254211.40.90.255254
92211.40.91.0/24211.40.91.1 to 211.40.91.254211.40.91.255254
93211.40.92.0/24211.40.92.1 to 211.40.92.254211.40.92.255254
94211.40.93.0/24211.40.93.1 to 211.40.93.254211.40.93.255254
95211.40.94.0/24211.40.94.1 to 211.40.94.254211.40.94.255254
96211.40.95.0/24211.40.95.1 to 211.40.95.254211.40.95.255254
97211.40.96.0/24211.40.96.1 to 211.40.96.254211.40.96.255254
98211.40.97.0/24211.40.97.1 to 211.40.97.254211.40.97.255254
99211.40.98.0/24211.40.98.1 to 211.40.98.254211.40.98.255254
100211.40.99.0/24211.40.99.1 to 211.40.99.254211.40.99.255254
101211.40.100.0/24211.40.100.1 to 211.40.100.254211.40.100.255254
102211.40.101.0/24211.40.101.1 to 211.40.101.254211.40.101.255254
103211.40.102.0/24211.40.102.1 to 211.40.102.254211.40.102.255254
104211.40.103.0/24211.40.103.1 to 211.40.103.254211.40.103.255254
105211.40.104.0/24211.40.104.1 to 211.40.104.254211.40.104.255254
106211.40.105.0/24211.40.105.1 to 211.40.105.254211.40.105.255254
107211.40.106.0/24211.40.106.1 to 211.40.106.254211.40.106.255254
108211.40.107.0/24211.40.107.1 to 211.40.107.254211.40.107.255254
109211.40.108.0/24211.40.108.1 to 211.40.108.254211.40.108.255254
110211.40.109.0/24211.40.109.1 to 211.40.109.254211.40.109.255254
111211.40.110.0/24211.40.110.1 to 211.40.110.254211.40.110.255254
112211.40.111.0/24211.40.111.1 to 211.40.111.254211.40.111.255254
113211.40.112.0/24211.40.112.1 to 211.40.112.254211.40.112.255254
114211.40.113.0/24211.40.113.1 to 211.40.113.254211.40.113.255254
115211.40.114.0/24211.40.114.1 to 211.40.114.254211.40.114.255254
116211.40.115.0/24211.40.115.1 to 211.40.115.254211.40.115.255254
117211.40.116.0/24211.40.116.1 to 211.40.116.254211.40.116.255254
118211.40.117.0/24211.40.117.1 to 211.40.117.254211.40.117.255254
119211.40.118.0/24211.40.118.1 to 211.40.118.254211.40.118.255254
120211.40.119.0/24211.40.119.1 to 211.40.119.254211.40.119.255254
121211.40.120.0/24211.40.120.1 to 211.40.120.254211.40.120.255254
122211.40.121.0/24211.40.121.1 to 211.40.121.254211.40.121.255254
123211.40.122.0/24211.40.122.1 to 211.40.122.254211.40.122.255254
124211.40.123.0/24211.40.123.1 to 211.40.123.254211.40.123.255254
125211.40.124.0/24211.40.124.1 to 211.40.124.254211.40.124.255254
126211.40.125.0/24211.40.125.1 to 211.40.125.254211.40.125.255254
127211.40.126.0/24211.40.126.1 to 211.40.126.254211.40.126.255254
128211.40.127.0/24211.40.127.1 to 211.40.127.254211.40.127.255254
129211.40.128.0/24211.40.128.1 to 211.40.128.254211.40.128.255254
130211.40.129.0/24211.40.129.1 to 211.40.129.254211.40.129.255254
131211.40.130.0/24211.40.130.1 to 211.40.130.254211.40.130.255254
132211.40.131.0/24211.40.131.1 to 211.40.131.254211.40.131.255254
133211.40.132.0/24211.40.132.1 to 211.40.132.254211.40.132.255254
134211.40.133.0/24211.40.133.1 to 211.40.133.254211.40.133.255254
135211.40.134.0/24211.40.134.1 to 211.40.134.254211.40.134.255254
136211.40.135.0/24211.40.135.1 to 211.40.135.254211.40.135.255254
137211.40.136.0/24211.40.136.1 to 211.40.136.254211.40.136.255254
138211.40.137.0/24211.40.137.1 to 211.40.137.254211.40.137.255254
139211.40.138.0/24211.40.138.1 to 211.40.138.254211.40.138.255254
140211.40.139.0/24211.40.139.1 to 211.40.139.254211.40.139.255254
141211.40.140.0/24211.40.140.1 to 211.40.140.254211.40.140.255254
142211.40.141.0/24211.40.141.1 to 211.40.141.254211.40.141.255254
143211.40.142.0/24211.40.142.1 to 211.40.142.254211.40.142.255254
144211.40.143.0/24211.40.143.1 to 211.40.143.254211.40.143.255254
145211.40.144.0/24211.40.144.1 to 211.40.144.254211.40.144.255254
146211.40.145.0/24211.40.145.1 to 211.40.145.254211.40.145.255254
147211.40.146.0/24211.40.146.1 to 211.40.146.254211.40.146.255254
148211.40.147.0/24211.40.147.1 to 211.40.147.254211.40.147.255254
149211.40.148.0/24211.40.148.1 to 211.40.148.254211.40.148.255254
150211.40.149.0/24211.40.149.1 to 211.40.149.254211.40.149.255254
151211.40.150.0/24211.40.150.1 to 211.40.150.254211.40.150.255254
152211.40.151.0/24211.40.151.1 to 211.40.151.254211.40.151.255254
153211.40.152.0/24211.40.152.1 to 211.40.152.254211.40.152.255254
154211.40.153.0/24211.40.153.1 to 211.40.153.254211.40.153.255254
155211.40.154.0/24211.40.154.1 to 211.40.154.254211.40.154.255254
156211.40.155.0/24211.40.155.1 to 211.40.155.254211.40.155.255254
157211.40.156.0/24211.40.156.1 to 211.40.156.254211.40.156.255254
158211.40.157.0/24211.40.157.1 to 211.40.157.254211.40.157.255254
159211.40.158.0/24211.40.158.1 to 211.40.158.254211.40.158.255254
160211.40.159.0/24211.40.159.1 to 211.40.159.254211.40.159.255254
161211.40.160.0/24211.40.160.1 to 211.40.160.254211.40.160.255254
162211.40.161.0/24211.40.161.1 to 211.40.161.254211.40.161.255254
163211.40.162.0/24211.40.162.1 to 211.40.162.254211.40.162.255254
164211.40.163.0/24211.40.163.1 to 211.40.163.254211.40.163.255254
165211.40.164.0/24211.40.164.1 to 211.40.164.254211.40.164.255254
166211.40.165.0/24211.40.165.1 to 211.40.165.254211.40.165.255254
167211.40.166.0/24211.40.166.1 to 211.40.166.254211.40.166.255254
168211.40.167.0/24211.40.167.1 to 211.40.167.254211.40.167.255254
169211.40.168.0/24211.40.168.1 to 211.40.168.254211.40.168.255254
170211.40.169.0/24211.40.169.1 to 211.40.169.254211.40.169.255254
171211.40.170.0/24211.40.170.1 to 211.40.170.254211.40.170.255254
172211.40.171.0/24211.40.171.1 to 211.40.171.254211.40.171.255254
173211.40.172.0/24211.40.172.1 to 211.40.172.254211.40.172.255254
174211.40.173.0/24211.40.173.1 to 211.40.173.254211.40.173.255254
175211.40.174.0/24211.40.174.1 to 211.40.174.254211.40.174.255254
176211.40.175.0/24211.40.175.1 to 211.40.175.254211.40.175.255254
177211.40.176.0/24211.40.176.1 to 211.40.176.254211.40.176.255254
178211.40.177.0/24211.40.177.1 to 211.40.177.254211.40.177.255254
179211.40.178.0/24211.40.178.1 to 211.40.178.254211.40.178.255254
180211.40.179.0/24211.40.179.1 to 211.40.179.254211.40.179.255254
181211.40.180.0/24211.40.180.1 to 211.40.180.254211.40.180.255254
182211.40.181.0/24211.40.181.1 to 211.40.181.254211.40.181.255254
183211.40.182.0/24211.40.182.1 to 211.40.182.254211.40.182.255254
184211.40.183.0/24211.40.183.1 to 211.40.183.254211.40.183.255254
185211.40.184.0/24211.40.184.1 to 211.40.184.254211.40.184.255254
186211.40.185.0/24211.40.185.1 to 211.40.185.254211.40.185.255254
187211.40.186.0/24211.40.186.1 to 211.40.186.254211.40.186.255254
188211.40.187.0/24211.40.187.1 to 211.40.187.254211.40.187.255254
189211.40.188.0/24211.40.188.1 to 211.40.188.254211.40.188.255254
190211.40.189.0/24211.40.189.1 to 211.40.189.254211.40.189.255254
191211.40.190.0/24211.40.190.1 to 211.40.190.254211.40.190.255254
192211.40.191.0/24211.40.191.1 to 211.40.191.254211.40.191.255254
193211.40.192.0/24211.40.192.1 to 211.40.192.254211.40.192.255254
194211.40.193.0/24211.40.193.1 to 211.40.193.254211.40.193.255254
195211.40.194.0/24211.40.194.1 to 211.40.194.254211.40.194.255254
196211.40.195.0/24211.40.195.1 to 211.40.195.254211.40.195.255254
197211.40.196.0/24211.40.196.1 to 211.40.196.254211.40.196.255254
198211.40.197.0/24211.40.197.1 to 211.40.197.254211.40.197.255254
199211.40.198.0/24211.40.198.1 to 211.40.198.254211.40.198.255254
200211.40.199.0/24211.40.199.1 to 211.40.199.254211.40.199.255254
201211.40.200.0/24211.40.200.1 to 211.40.200.254211.40.200.255254
202211.40.201.0/24211.40.201.1 to 211.40.201.254211.40.201.255254
203211.40.202.0/24211.40.202.1 to 211.40.202.254211.40.202.255254
204211.40.203.0/24211.40.203.1 to 211.40.203.254211.40.203.255254
205211.40.204.0/24211.40.204.1 to 211.40.204.254211.40.204.255254
206211.40.205.0/24211.40.205.1 to 211.40.205.254211.40.205.255254
207211.40.206.0/24211.40.206.1 to 211.40.206.254211.40.206.255254
208211.40.207.0/24211.40.207.1 to 211.40.207.254211.40.207.255254
209211.40.208.0/24211.40.208.1 to 211.40.208.254211.40.208.255254
210211.40.209.0/24211.40.209.1 to 211.40.209.254211.40.209.255254
211211.40.210.0/24211.40.210.1 to 211.40.210.254211.40.210.255254
212211.40.211.0/24211.40.211.1 to 211.40.211.254211.40.211.255254
213211.40.212.0/24211.40.212.1 to 211.40.212.254211.40.212.255254
214211.40.213.0/24211.40.213.1 to 211.40.213.254211.40.213.255254
215211.40.214.0/24211.40.214.1 to 211.40.214.254211.40.214.255254
216211.40.215.0/24211.40.215.1 to 211.40.215.254211.40.215.255254
217211.40.216.0/24211.40.216.1 to 211.40.216.254211.40.216.255254
218211.40.217.0/24211.40.217.1 to 211.40.217.254211.40.217.255254
219211.40.218.0/24211.40.218.1 to 211.40.218.254211.40.218.255254
220211.40.219.0/24211.40.219.1 to 211.40.219.254211.40.219.255254
221211.40.220.0/24211.40.220.1 to 211.40.220.254211.40.220.255254
222211.40.221.0/24211.40.221.1 to 211.40.221.254211.40.221.255254
223211.40.222.0/24211.40.222.1 to 211.40.222.254211.40.222.255254
224211.40.223.0/24211.40.223.1 to 211.40.223.254211.40.223.255254
225211.40.224.0/24211.40.224.1 to 211.40.224.254211.40.224.255254
226211.40.225.0/24211.40.225.1 to 211.40.225.254211.40.225.255254
227211.40.226.0/24211.40.226.1 to 211.40.226.254211.40.226.255254
228211.40.227.0/24211.40.227.1 to 211.40.227.254211.40.227.255254
229211.40.228.0/24211.40.228.1 to 211.40.228.254211.40.228.255254
230211.40.229.0/24211.40.229.1 to 211.40.229.254211.40.229.255254
231211.40.230.0/24211.40.230.1 to 211.40.230.254211.40.230.255254
232211.40.231.0/24211.40.231.1 to 211.40.231.254211.40.231.255254
233211.40.232.0/24211.40.232.1 to 211.40.232.254211.40.232.255254
234211.40.233.0/24211.40.233.1 to 211.40.233.254211.40.233.255254
235211.40.234.0/24211.40.234.1 to 211.40.234.254211.40.234.255254
236211.40.235.0/24211.40.235.1 to 211.40.235.254211.40.235.255254
237211.40.236.0/24211.40.236.1 to 211.40.236.254211.40.236.255254
238211.40.237.0/24211.40.237.1 to 211.40.237.254211.40.237.255254
239211.40.238.0/24211.40.238.1 to 211.40.238.254211.40.238.255254
240211.40.239.0/24211.40.239.1 to 211.40.239.254211.40.239.255254
241211.40.240.0/24211.40.240.1 to 211.40.240.254211.40.240.255254
242211.40.241.0/24211.40.241.1 to 211.40.241.254211.40.241.255254
243211.40.242.0/24211.40.242.1 to 211.40.242.254211.40.242.255254
244211.40.243.0/24211.40.243.1 to 211.40.243.254211.40.243.255254
245211.40.244.0/24211.40.244.1 to 211.40.244.254211.40.244.255254
246211.40.245.0/24211.40.245.1 to 211.40.245.254211.40.245.255254
247211.40.246.0/24211.40.246.1 to 211.40.246.254211.40.246.255254
248211.40.247.0/24211.40.247.1 to 211.40.247.254211.40.247.255254
249211.40.248.0/24211.40.248.1 to 211.40.248.254211.40.248.255254
250211.40.249.0/24211.40.249.1 to 211.40.249.254211.40.249.255254
251211.40.250.0/24211.40.250.1 to 211.40.250.254211.40.250.255254
252211.40.251.0/24211.40.251.1 to 211.40.251.254211.40.251.255254
253211.40.252.0/24211.40.252.1 to 211.40.252.254211.40.252.255254
254211.40.253.0/24211.40.253.1 to 211.40.253.254211.40.253.255254
255211.40.254.0/24211.40.254.1 to 211.40.254.254211.40.254.255254
256211.40.255.0/24211.40.255.1 to 211.40.255.254211.40.255.255254

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.