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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.

Network116.97.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
116.97.0.0
Broadcast address
116.97.255.255
First usable
116.97.0.1
Last usable
116.97.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 74610000 · Integer 1952514048 to 1952579583
Reverse DNS zone
97.116.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110100.01100001..00000000.00000000116.97.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01110100.01100001..00000000.00000000116.97.0.0
Broadcast01110100.01100001..11111111.11111111116.97.255.255
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

116.97.0.0/16 makes 256 subnets of /24.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1116.97.0.0/24116.97.0.1 to 116.97.0.254116.97.0.255254
2116.97.1.0/24116.97.1.1 to 116.97.1.254116.97.1.255254
3116.97.2.0/24116.97.2.1 to 116.97.2.254116.97.2.255254
4116.97.3.0/24116.97.3.1 to 116.97.3.254116.97.3.255254
5116.97.4.0/24116.97.4.1 to 116.97.4.254116.97.4.255254
6116.97.5.0/24116.97.5.1 to 116.97.5.254116.97.5.255254
7116.97.6.0/24116.97.6.1 to 116.97.6.254116.97.6.255254
8116.97.7.0/24116.97.7.1 to 116.97.7.254116.97.7.255254
9116.97.8.0/24116.97.8.1 to 116.97.8.254116.97.8.255254
10116.97.9.0/24116.97.9.1 to 116.97.9.254116.97.9.255254
11116.97.10.0/24116.97.10.1 to 116.97.10.254116.97.10.255254
12116.97.11.0/24116.97.11.1 to 116.97.11.254116.97.11.255254
13116.97.12.0/24116.97.12.1 to 116.97.12.254116.97.12.255254
14116.97.13.0/24116.97.13.1 to 116.97.13.254116.97.13.255254
15116.97.14.0/24116.97.14.1 to 116.97.14.254116.97.14.255254
16116.97.15.0/24116.97.15.1 to 116.97.15.254116.97.15.255254
17116.97.16.0/24116.97.16.1 to 116.97.16.254116.97.16.255254
18116.97.17.0/24116.97.17.1 to 116.97.17.254116.97.17.255254
19116.97.18.0/24116.97.18.1 to 116.97.18.254116.97.18.255254
20116.97.19.0/24116.97.19.1 to 116.97.19.254116.97.19.255254
21116.97.20.0/24116.97.20.1 to 116.97.20.254116.97.20.255254
22116.97.21.0/24116.97.21.1 to 116.97.21.254116.97.21.255254
23116.97.22.0/24116.97.22.1 to 116.97.22.254116.97.22.255254
24116.97.23.0/24116.97.23.1 to 116.97.23.254116.97.23.255254
25116.97.24.0/24116.97.24.1 to 116.97.24.254116.97.24.255254
26116.97.25.0/24116.97.25.1 to 116.97.25.254116.97.25.255254
27116.97.26.0/24116.97.26.1 to 116.97.26.254116.97.26.255254
28116.97.27.0/24116.97.27.1 to 116.97.27.254116.97.27.255254
29116.97.28.0/24116.97.28.1 to 116.97.28.254116.97.28.255254
30116.97.29.0/24116.97.29.1 to 116.97.29.254116.97.29.255254
31116.97.30.0/24116.97.30.1 to 116.97.30.254116.97.30.255254
32116.97.31.0/24116.97.31.1 to 116.97.31.254116.97.31.255254
33116.97.32.0/24116.97.32.1 to 116.97.32.254116.97.32.255254
34116.97.33.0/24116.97.33.1 to 116.97.33.254116.97.33.255254
35116.97.34.0/24116.97.34.1 to 116.97.34.254116.97.34.255254
36116.97.35.0/24116.97.35.1 to 116.97.35.254116.97.35.255254
37116.97.36.0/24116.97.36.1 to 116.97.36.254116.97.36.255254
38116.97.37.0/24116.97.37.1 to 116.97.37.254116.97.37.255254
39116.97.38.0/24116.97.38.1 to 116.97.38.254116.97.38.255254
40116.97.39.0/24116.97.39.1 to 116.97.39.254116.97.39.255254
41116.97.40.0/24116.97.40.1 to 116.97.40.254116.97.40.255254
42116.97.41.0/24116.97.41.1 to 116.97.41.254116.97.41.255254
43116.97.42.0/24116.97.42.1 to 116.97.42.254116.97.42.255254
44116.97.43.0/24116.97.43.1 to 116.97.43.254116.97.43.255254
45116.97.44.0/24116.97.44.1 to 116.97.44.254116.97.44.255254
46116.97.45.0/24116.97.45.1 to 116.97.45.254116.97.45.255254
47116.97.46.0/24116.97.46.1 to 116.97.46.254116.97.46.255254
48116.97.47.0/24116.97.47.1 to 116.97.47.254116.97.47.255254
49116.97.48.0/24116.97.48.1 to 116.97.48.254116.97.48.255254
50116.97.49.0/24116.97.49.1 to 116.97.49.254116.97.49.255254
51116.97.50.0/24116.97.50.1 to 116.97.50.254116.97.50.255254
52116.97.51.0/24116.97.51.1 to 116.97.51.254116.97.51.255254
53116.97.52.0/24116.97.52.1 to 116.97.52.254116.97.52.255254
54116.97.53.0/24116.97.53.1 to 116.97.53.254116.97.53.255254
55116.97.54.0/24116.97.54.1 to 116.97.54.254116.97.54.255254
56116.97.55.0/24116.97.55.1 to 116.97.55.254116.97.55.255254
57116.97.56.0/24116.97.56.1 to 116.97.56.254116.97.56.255254
58116.97.57.0/24116.97.57.1 to 116.97.57.254116.97.57.255254
59116.97.58.0/24116.97.58.1 to 116.97.58.254116.97.58.255254
60116.97.59.0/24116.97.59.1 to 116.97.59.254116.97.59.255254
61116.97.60.0/24116.97.60.1 to 116.97.60.254116.97.60.255254
62116.97.61.0/24116.97.61.1 to 116.97.61.254116.97.61.255254
63116.97.62.0/24116.97.62.1 to 116.97.62.254116.97.62.255254
64116.97.63.0/24116.97.63.1 to 116.97.63.254116.97.63.255254
65116.97.64.0/24116.97.64.1 to 116.97.64.254116.97.64.255254
66116.97.65.0/24116.97.65.1 to 116.97.65.254116.97.65.255254
67116.97.66.0/24116.97.66.1 to 116.97.66.254116.97.66.255254
68116.97.67.0/24116.97.67.1 to 116.97.67.254116.97.67.255254
69116.97.68.0/24116.97.68.1 to 116.97.68.254116.97.68.255254
70116.97.69.0/24116.97.69.1 to 116.97.69.254116.97.69.255254
71116.97.70.0/24116.97.70.1 to 116.97.70.254116.97.70.255254
72116.97.71.0/24116.97.71.1 to 116.97.71.254116.97.71.255254
73116.97.72.0/24116.97.72.1 to 116.97.72.254116.97.72.255254
74116.97.73.0/24116.97.73.1 to 116.97.73.254116.97.73.255254
75116.97.74.0/24116.97.74.1 to 116.97.74.254116.97.74.255254
76116.97.75.0/24116.97.75.1 to 116.97.75.254116.97.75.255254
77116.97.76.0/24116.97.76.1 to 116.97.76.254116.97.76.255254
78116.97.77.0/24116.97.77.1 to 116.97.77.254116.97.77.255254
79116.97.78.0/24116.97.78.1 to 116.97.78.254116.97.78.255254
80116.97.79.0/24116.97.79.1 to 116.97.79.254116.97.79.255254
81116.97.80.0/24116.97.80.1 to 116.97.80.254116.97.80.255254
82116.97.81.0/24116.97.81.1 to 116.97.81.254116.97.81.255254
83116.97.82.0/24116.97.82.1 to 116.97.82.254116.97.82.255254
84116.97.83.0/24116.97.83.1 to 116.97.83.254116.97.83.255254
85116.97.84.0/24116.97.84.1 to 116.97.84.254116.97.84.255254
86116.97.85.0/24116.97.85.1 to 116.97.85.254116.97.85.255254
87116.97.86.0/24116.97.86.1 to 116.97.86.254116.97.86.255254
88116.97.87.0/24116.97.87.1 to 116.97.87.254116.97.87.255254
89116.97.88.0/24116.97.88.1 to 116.97.88.254116.97.88.255254
90116.97.89.0/24116.97.89.1 to 116.97.89.254116.97.89.255254
91116.97.90.0/24116.97.90.1 to 116.97.90.254116.97.90.255254
92116.97.91.0/24116.97.91.1 to 116.97.91.254116.97.91.255254
93116.97.92.0/24116.97.92.1 to 116.97.92.254116.97.92.255254
94116.97.93.0/24116.97.93.1 to 116.97.93.254116.97.93.255254
95116.97.94.0/24116.97.94.1 to 116.97.94.254116.97.94.255254
96116.97.95.0/24116.97.95.1 to 116.97.95.254116.97.95.255254
97116.97.96.0/24116.97.96.1 to 116.97.96.254116.97.96.255254
98116.97.97.0/24116.97.97.1 to 116.97.97.254116.97.97.255254
99116.97.98.0/24116.97.98.1 to 116.97.98.254116.97.98.255254
100116.97.99.0/24116.97.99.1 to 116.97.99.254116.97.99.255254
101116.97.100.0/24116.97.100.1 to 116.97.100.254116.97.100.255254
102116.97.101.0/24116.97.101.1 to 116.97.101.254116.97.101.255254
103116.97.102.0/24116.97.102.1 to 116.97.102.254116.97.102.255254
104116.97.103.0/24116.97.103.1 to 116.97.103.254116.97.103.255254
105116.97.104.0/24116.97.104.1 to 116.97.104.254116.97.104.255254
106116.97.105.0/24116.97.105.1 to 116.97.105.254116.97.105.255254
107116.97.106.0/24116.97.106.1 to 116.97.106.254116.97.106.255254
108116.97.107.0/24116.97.107.1 to 116.97.107.254116.97.107.255254
109116.97.108.0/24116.97.108.1 to 116.97.108.254116.97.108.255254
110116.97.109.0/24116.97.109.1 to 116.97.109.254116.97.109.255254
111116.97.110.0/24116.97.110.1 to 116.97.110.254116.97.110.255254
112116.97.111.0/24116.97.111.1 to 116.97.111.254116.97.111.255254
113116.97.112.0/24116.97.112.1 to 116.97.112.254116.97.112.255254
114116.97.113.0/24116.97.113.1 to 116.97.113.254116.97.113.255254
115116.97.114.0/24116.97.114.1 to 116.97.114.254116.97.114.255254
116116.97.115.0/24116.97.115.1 to 116.97.115.254116.97.115.255254
117116.97.116.0/24116.97.116.1 to 116.97.116.254116.97.116.255254
118116.97.117.0/24116.97.117.1 to 116.97.117.254116.97.117.255254
119116.97.118.0/24116.97.118.1 to 116.97.118.254116.97.118.255254
120116.97.119.0/24116.97.119.1 to 116.97.119.254116.97.119.255254
121116.97.120.0/24116.97.120.1 to 116.97.120.254116.97.120.255254
122116.97.121.0/24116.97.121.1 to 116.97.121.254116.97.121.255254
123116.97.122.0/24116.97.122.1 to 116.97.122.254116.97.122.255254
124116.97.123.0/24116.97.123.1 to 116.97.123.254116.97.123.255254
125116.97.124.0/24116.97.124.1 to 116.97.124.254116.97.124.255254
126116.97.125.0/24116.97.125.1 to 116.97.125.254116.97.125.255254
127116.97.126.0/24116.97.126.1 to 116.97.126.254116.97.126.255254
128116.97.127.0/24116.97.127.1 to 116.97.127.254116.97.127.255254
129116.97.128.0/24116.97.128.1 to 116.97.128.254116.97.128.255254
130116.97.129.0/24116.97.129.1 to 116.97.129.254116.97.129.255254
131116.97.130.0/24116.97.130.1 to 116.97.130.254116.97.130.255254
132116.97.131.0/24116.97.131.1 to 116.97.131.254116.97.131.255254
133116.97.132.0/24116.97.132.1 to 116.97.132.254116.97.132.255254
134116.97.133.0/24116.97.133.1 to 116.97.133.254116.97.133.255254
135116.97.134.0/24116.97.134.1 to 116.97.134.254116.97.134.255254
136116.97.135.0/24116.97.135.1 to 116.97.135.254116.97.135.255254
137116.97.136.0/24116.97.136.1 to 116.97.136.254116.97.136.255254
138116.97.137.0/24116.97.137.1 to 116.97.137.254116.97.137.255254
139116.97.138.0/24116.97.138.1 to 116.97.138.254116.97.138.255254
140116.97.139.0/24116.97.139.1 to 116.97.139.254116.97.139.255254
141116.97.140.0/24116.97.140.1 to 116.97.140.254116.97.140.255254
142116.97.141.0/24116.97.141.1 to 116.97.141.254116.97.141.255254
143116.97.142.0/24116.97.142.1 to 116.97.142.254116.97.142.255254
144116.97.143.0/24116.97.143.1 to 116.97.143.254116.97.143.255254
145116.97.144.0/24116.97.144.1 to 116.97.144.254116.97.144.255254
146116.97.145.0/24116.97.145.1 to 116.97.145.254116.97.145.255254
147116.97.146.0/24116.97.146.1 to 116.97.146.254116.97.146.255254
148116.97.147.0/24116.97.147.1 to 116.97.147.254116.97.147.255254
149116.97.148.0/24116.97.148.1 to 116.97.148.254116.97.148.255254
150116.97.149.0/24116.97.149.1 to 116.97.149.254116.97.149.255254
151116.97.150.0/24116.97.150.1 to 116.97.150.254116.97.150.255254
152116.97.151.0/24116.97.151.1 to 116.97.151.254116.97.151.255254
153116.97.152.0/24116.97.152.1 to 116.97.152.254116.97.152.255254
154116.97.153.0/24116.97.153.1 to 116.97.153.254116.97.153.255254
155116.97.154.0/24116.97.154.1 to 116.97.154.254116.97.154.255254
156116.97.155.0/24116.97.155.1 to 116.97.155.254116.97.155.255254
157116.97.156.0/24116.97.156.1 to 116.97.156.254116.97.156.255254
158116.97.157.0/24116.97.157.1 to 116.97.157.254116.97.157.255254
159116.97.158.0/24116.97.158.1 to 116.97.158.254116.97.158.255254
160116.97.159.0/24116.97.159.1 to 116.97.159.254116.97.159.255254
161116.97.160.0/24116.97.160.1 to 116.97.160.254116.97.160.255254
162116.97.161.0/24116.97.161.1 to 116.97.161.254116.97.161.255254
163116.97.162.0/24116.97.162.1 to 116.97.162.254116.97.162.255254
164116.97.163.0/24116.97.163.1 to 116.97.163.254116.97.163.255254
165116.97.164.0/24116.97.164.1 to 116.97.164.254116.97.164.255254
166116.97.165.0/24116.97.165.1 to 116.97.165.254116.97.165.255254
167116.97.166.0/24116.97.166.1 to 116.97.166.254116.97.166.255254
168116.97.167.0/24116.97.167.1 to 116.97.167.254116.97.167.255254
169116.97.168.0/24116.97.168.1 to 116.97.168.254116.97.168.255254
170116.97.169.0/24116.97.169.1 to 116.97.169.254116.97.169.255254
171116.97.170.0/24116.97.170.1 to 116.97.170.254116.97.170.255254
172116.97.171.0/24116.97.171.1 to 116.97.171.254116.97.171.255254
173116.97.172.0/24116.97.172.1 to 116.97.172.254116.97.172.255254
174116.97.173.0/24116.97.173.1 to 116.97.173.254116.97.173.255254
175116.97.174.0/24116.97.174.1 to 116.97.174.254116.97.174.255254
176116.97.175.0/24116.97.175.1 to 116.97.175.254116.97.175.255254
177116.97.176.0/24116.97.176.1 to 116.97.176.254116.97.176.255254
178116.97.177.0/24116.97.177.1 to 116.97.177.254116.97.177.255254
179116.97.178.0/24116.97.178.1 to 116.97.178.254116.97.178.255254
180116.97.179.0/24116.97.179.1 to 116.97.179.254116.97.179.255254
181116.97.180.0/24116.97.180.1 to 116.97.180.254116.97.180.255254
182116.97.181.0/24116.97.181.1 to 116.97.181.254116.97.181.255254
183116.97.182.0/24116.97.182.1 to 116.97.182.254116.97.182.255254
184116.97.183.0/24116.97.183.1 to 116.97.183.254116.97.183.255254
185116.97.184.0/24116.97.184.1 to 116.97.184.254116.97.184.255254
186116.97.185.0/24116.97.185.1 to 116.97.185.254116.97.185.255254
187116.97.186.0/24116.97.186.1 to 116.97.186.254116.97.186.255254
188116.97.187.0/24116.97.187.1 to 116.97.187.254116.97.187.255254
189116.97.188.0/24116.97.188.1 to 116.97.188.254116.97.188.255254
190116.97.189.0/24116.97.189.1 to 116.97.189.254116.97.189.255254
191116.97.190.0/24116.97.190.1 to 116.97.190.254116.97.190.255254
192116.97.191.0/24116.97.191.1 to 116.97.191.254116.97.191.255254
193116.97.192.0/24116.97.192.1 to 116.97.192.254116.97.192.255254
194116.97.193.0/24116.97.193.1 to 116.97.193.254116.97.193.255254
195116.97.194.0/24116.97.194.1 to 116.97.194.254116.97.194.255254
196116.97.195.0/24116.97.195.1 to 116.97.195.254116.97.195.255254
197116.97.196.0/24116.97.196.1 to 116.97.196.254116.97.196.255254
198116.97.197.0/24116.97.197.1 to 116.97.197.254116.97.197.255254
199116.97.198.0/24116.97.198.1 to 116.97.198.254116.97.198.255254
200116.97.199.0/24116.97.199.1 to 116.97.199.254116.97.199.255254
201116.97.200.0/24116.97.200.1 to 116.97.200.254116.97.200.255254
202116.97.201.0/24116.97.201.1 to 116.97.201.254116.97.201.255254
203116.97.202.0/24116.97.202.1 to 116.97.202.254116.97.202.255254
204116.97.203.0/24116.97.203.1 to 116.97.203.254116.97.203.255254
205116.97.204.0/24116.97.204.1 to 116.97.204.254116.97.204.255254
206116.97.205.0/24116.97.205.1 to 116.97.205.254116.97.205.255254
207116.97.206.0/24116.97.206.1 to 116.97.206.254116.97.206.255254
208116.97.207.0/24116.97.207.1 to 116.97.207.254116.97.207.255254
209116.97.208.0/24116.97.208.1 to 116.97.208.254116.97.208.255254
210116.97.209.0/24116.97.209.1 to 116.97.209.254116.97.209.255254
211116.97.210.0/24116.97.210.1 to 116.97.210.254116.97.210.255254
212116.97.211.0/24116.97.211.1 to 116.97.211.254116.97.211.255254
213116.97.212.0/24116.97.212.1 to 116.97.212.254116.97.212.255254
214116.97.213.0/24116.97.213.1 to 116.97.213.254116.97.213.255254
215116.97.214.0/24116.97.214.1 to 116.97.214.254116.97.214.255254
216116.97.215.0/24116.97.215.1 to 116.97.215.254116.97.215.255254
217116.97.216.0/24116.97.216.1 to 116.97.216.254116.97.216.255254
218116.97.217.0/24116.97.217.1 to 116.97.217.254116.97.217.255254
219116.97.218.0/24116.97.218.1 to 116.97.218.254116.97.218.255254
220116.97.219.0/24116.97.219.1 to 116.97.219.254116.97.219.255254
221116.97.220.0/24116.97.220.1 to 116.97.220.254116.97.220.255254
222116.97.221.0/24116.97.221.1 to 116.97.221.254116.97.221.255254
223116.97.222.0/24116.97.222.1 to 116.97.222.254116.97.222.255254
224116.97.223.0/24116.97.223.1 to 116.97.223.254116.97.223.255254
225116.97.224.0/24116.97.224.1 to 116.97.224.254116.97.224.255254
226116.97.225.0/24116.97.225.1 to 116.97.225.254116.97.225.255254
227116.97.226.0/24116.97.226.1 to 116.97.226.254116.97.226.255254
228116.97.227.0/24116.97.227.1 to 116.97.227.254116.97.227.255254
229116.97.228.0/24116.97.228.1 to 116.97.228.254116.97.228.255254
230116.97.229.0/24116.97.229.1 to 116.97.229.254116.97.229.255254
231116.97.230.0/24116.97.230.1 to 116.97.230.254116.97.230.255254
232116.97.231.0/24116.97.231.1 to 116.97.231.254116.97.231.255254
233116.97.232.0/24116.97.232.1 to 116.97.232.254116.97.232.255254
234116.97.233.0/24116.97.233.1 to 116.97.233.254116.97.233.255254
235116.97.234.0/24116.97.234.1 to 116.97.234.254116.97.234.255254
236116.97.235.0/24116.97.235.1 to 116.97.235.254116.97.235.255254
237116.97.236.0/24116.97.236.1 to 116.97.236.254116.97.236.255254
238116.97.237.0/24116.97.237.1 to 116.97.237.254116.97.237.255254
239116.97.238.0/24116.97.238.1 to 116.97.238.254116.97.238.255254
240116.97.239.0/24116.97.239.1 to 116.97.239.254116.97.239.255254
241116.97.240.0/24116.97.240.1 to 116.97.240.254116.97.240.255254
242116.97.241.0/24116.97.241.1 to 116.97.241.254116.97.241.255254
243116.97.242.0/24116.97.242.1 to 116.97.242.254116.97.242.255254
244116.97.243.0/24116.97.243.1 to 116.97.243.254116.97.243.255254
245116.97.244.0/24116.97.244.1 to 116.97.244.254116.97.244.255254
246116.97.245.0/24116.97.245.1 to 116.97.245.254116.97.245.255254
247116.97.246.0/24116.97.246.1 to 116.97.246.254116.97.246.255254
248116.97.247.0/24116.97.247.1 to 116.97.247.254116.97.247.255254
249116.97.248.0/24116.97.248.1 to 116.97.248.254116.97.248.255254
250116.97.249.0/24116.97.249.1 to 116.97.249.254116.97.249.255254
251116.97.250.0/24116.97.250.1 to 116.97.250.254116.97.250.255254
252116.97.251.0/24116.97.251.1 to 116.97.251.254116.97.251.255254
253116.97.252.0/24116.97.252.1 to 116.97.252.254116.97.252.255254
254116.97.253.0/24116.97.253.1 to 116.97.253.254116.97.253.255254
255116.97.254.0/24116.97.254.1 to 116.97.254.254116.97.254.255254
256116.97.255.0/24116.97.255.1 to 116.97.255.254116.97.255.255254

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.