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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.

Network108.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
108.0.0.0
Broadcast address
108.255.255.255
First usable
108.0.0.1
Last usable
108.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 6C000000 · Integer 1811939328 to 1828716543
Reverse DNS zone
108.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01101100..00000000.00000000.00000000108.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01101100..00000000.00000000.00000000108.0.0.0
Broadcast01101100..11111111.11111111.11111111108.255.255.255
Split into smaller subnets/16
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

108.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1108.0.0.0/16108.0.0.1 to 108.0.255.254108.0.255.25565,534
2108.1.0.0/16108.1.0.1 to 108.1.255.254108.1.255.25565,534
3108.2.0.0/16108.2.0.1 to 108.2.255.254108.2.255.25565,534
4108.3.0.0/16108.3.0.1 to 108.3.255.254108.3.255.25565,534
5108.4.0.0/16108.4.0.1 to 108.4.255.254108.4.255.25565,534
6108.5.0.0/16108.5.0.1 to 108.5.255.254108.5.255.25565,534
7108.6.0.0/16108.6.0.1 to 108.6.255.254108.6.255.25565,534
8108.7.0.0/16108.7.0.1 to 108.7.255.254108.7.255.25565,534
9108.8.0.0/16108.8.0.1 to 108.8.255.254108.8.255.25565,534
10108.9.0.0/16108.9.0.1 to 108.9.255.254108.9.255.25565,534
11108.10.0.0/16108.10.0.1 to 108.10.255.254108.10.255.25565,534
12108.11.0.0/16108.11.0.1 to 108.11.255.254108.11.255.25565,534
13108.12.0.0/16108.12.0.1 to 108.12.255.254108.12.255.25565,534
14108.13.0.0/16108.13.0.1 to 108.13.255.254108.13.255.25565,534
15108.14.0.0/16108.14.0.1 to 108.14.255.254108.14.255.25565,534
16108.15.0.0/16108.15.0.1 to 108.15.255.254108.15.255.25565,534
17108.16.0.0/16108.16.0.1 to 108.16.255.254108.16.255.25565,534
18108.17.0.0/16108.17.0.1 to 108.17.255.254108.17.255.25565,534
19108.18.0.0/16108.18.0.1 to 108.18.255.254108.18.255.25565,534
20108.19.0.0/16108.19.0.1 to 108.19.255.254108.19.255.25565,534
21108.20.0.0/16108.20.0.1 to 108.20.255.254108.20.255.25565,534
22108.21.0.0/16108.21.0.1 to 108.21.255.254108.21.255.25565,534
23108.22.0.0/16108.22.0.1 to 108.22.255.254108.22.255.25565,534
24108.23.0.0/16108.23.0.1 to 108.23.255.254108.23.255.25565,534
25108.24.0.0/16108.24.0.1 to 108.24.255.254108.24.255.25565,534
26108.25.0.0/16108.25.0.1 to 108.25.255.254108.25.255.25565,534
27108.26.0.0/16108.26.0.1 to 108.26.255.254108.26.255.25565,534
28108.27.0.0/16108.27.0.1 to 108.27.255.254108.27.255.25565,534
29108.28.0.0/16108.28.0.1 to 108.28.255.254108.28.255.25565,534
30108.29.0.0/16108.29.0.1 to 108.29.255.254108.29.255.25565,534
31108.30.0.0/16108.30.0.1 to 108.30.255.254108.30.255.25565,534
32108.31.0.0/16108.31.0.1 to 108.31.255.254108.31.255.25565,534
33108.32.0.0/16108.32.0.1 to 108.32.255.254108.32.255.25565,534
34108.33.0.0/16108.33.0.1 to 108.33.255.254108.33.255.25565,534
35108.34.0.0/16108.34.0.1 to 108.34.255.254108.34.255.25565,534
36108.35.0.0/16108.35.0.1 to 108.35.255.254108.35.255.25565,534
37108.36.0.0/16108.36.0.1 to 108.36.255.254108.36.255.25565,534
38108.37.0.0/16108.37.0.1 to 108.37.255.254108.37.255.25565,534
39108.38.0.0/16108.38.0.1 to 108.38.255.254108.38.255.25565,534
40108.39.0.0/16108.39.0.1 to 108.39.255.254108.39.255.25565,534
41108.40.0.0/16108.40.0.1 to 108.40.255.254108.40.255.25565,534
42108.41.0.0/16108.41.0.1 to 108.41.255.254108.41.255.25565,534
43108.42.0.0/16108.42.0.1 to 108.42.255.254108.42.255.25565,534
44108.43.0.0/16108.43.0.1 to 108.43.255.254108.43.255.25565,534
45108.44.0.0/16108.44.0.1 to 108.44.255.254108.44.255.25565,534
46108.45.0.0/16108.45.0.1 to 108.45.255.254108.45.255.25565,534
47108.46.0.0/16108.46.0.1 to 108.46.255.254108.46.255.25565,534
48108.47.0.0/16108.47.0.1 to 108.47.255.254108.47.255.25565,534
49108.48.0.0/16108.48.0.1 to 108.48.255.254108.48.255.25565,534
50108.49.0.0/16108.49.0.1 to 108.49.255.254108.49.255.25565,534
51108.50.0.0/16108.50.0.1 to 108.50.255.254108.50.255.25565,534
52108.51.0.0/16108.51.0.1 to 108.51.255.254108.51.255.25565,534
53108.52.0.0/16108.52.0.1 to 108.52.255.254108.52.255.25565,534
54108.53.0.0/16108.53.0.1 to 108.53.255.254108.53.255.25565,534
55108.54.0.0/16108.54.0.1 to 108.54.255.254108.54.255.25565,534
56108.55.0.0/16108.55.0.1 to 108.55.255.254108.55.255.25565,534
57108.56.0.0/16108.56.0.1 to 108.56.255.254108.56.255.25565,534
58108.57.0.0/16108.57.0.1 to 108.57.255.254108.57.255.25565,534
59108.58.0.0/16108.58.0.1 to 108.58.255.254108.58.255.25565,534
60108.59.0.0/16108.59.0.1 to 108.59.255.254108.59.255.25565,534
61108.60.0.0/16108.60.0.1 to 108.60.255.254108.60.255.25565,534
62108.61.0.0/16108.61.0.1 to 108.61.255.254108.61.255.25565,534
63108.62.0.0/16108.62.0.1 to 108.62.255.254108.62.255.25565,534
64108.63.0.0/16108.63.0.1 to 108.63.255.254108.63.255.25565,534
65108.64.0.0/16108.64.0.1 to 108.64.255.254108.64.255.25565,534
66108.65.0.0/16108.65.0.1 to 108.65.255.254108.65.255.25565,534
67108.66.0.0/16108.66.0.1 to 108.66.255.254108.66.255.25565,534
68108.67.0.0/16108.67.0.1 to 108.67.255.254108.67.255.25565,534
69108.68.0.0/16108.68.0.1 to 108.68.255.254108.68.255.25565,534
70108.69.0.0/16108.69.0.1 to 108.69.255.254108.69.255.25565,534
71108.70.0.0/16108.70.0.1 to 108.70.255.254108.70.255.25565,534
72108.71.0.0/16108.71.0.1 to 108.71.255.254108.71.255.25565,534
73108.72.0.0/16108.72.0.1 to 108.72.255.254108.72.255.25565,534
74108.73.0.0/16108.73.0.1 to 108.73.255.254108.73.255.25565,534
75108.74.0.0/16108.74.0.1 to 108.74.255.254108.74.255.25565,534
76108.75.0.0/16108.75.0.1 to 108.75.255.254108.75.255.25565,534
77108.76.0.0/16108.76.0.1 to 108.76.255.254108.76.255.25565,534
78108.77.0.0/16108.77.0.1 to 108.77.255.254108.77.255.25565,534
79108.78.0.0/16108.78.0.1 to 108.78.255.254108.78.255.25565,534
80108.79.0.0/16108.79.0.1 to 108.79.255.254108.79.255.25565,534
81108.80.0.0/16108.80.0.1 to 108.80.255.254108.80.255.25565,534
82108.81.0.0/16108.81.0.1 to 108.81.255.254108.81.255.25565,534
83108.82.0.0/16108.82.0.1 to 108.82.255.254108.82.255.25565,534
84108.83.0.0/16108.83.0.1 to 108.83.255.254108.83.255.25565,534
85108.84.0.0/16108.84.0.1 to 108.84.255.254108.84.255.25565,534
86108.85.0.0/16108.85.0.1 to 108.85.255.254108.85.255.25565,534
87108.86.0.0/16108.86.0.1 to 108.86.255.254108.86.255.25565,534
88108.87.0.0/16108.87.0.1 to 108.87.255.254108.87.255.25565,534
89108.88.0.0/16108.88.0.1 to 108.88.255.254108.88.255.25565,534
90108.89.0.0/16108.89.0.1 to 108.89.255.254108.89.255.25565,534
91108.90.0.0/16108.90.0.1 to 108.90.255.254108.90.255.25565,534
92108.91.0.0/16108.91.0.1 to 108.91.255.254108.91.255.25565,534
93108.92.0.0/16108.92.0.1 to 108.92.255.254108.92.255.25565,534
94108.93.0.0/16108.93.0.1 to 108.93.255.254108.93.255.25565,534
95108.94.0.0/16108.94.0.1 to 108.94.255.254108.94.255.25565,534
96108.95.0.0/16108.95.0.1 to 108.95.255.254108.95.255.25565,534
97108.96.0.0/16108.96.0.1 to 108.96.255.254108.96.255.25565,534
98108.97.0.0/16108.97.0.1 to 108.97.255.254108.97.255.25565,534
99108.98.0.0/16108.98.0.1 to 108.98.255.254108.98.255.25565,534
100108.99.0.0/16108.99.0.1 to 108.99.255.254108.99.255.25565,534
101108.100.0.0/16108.100.0.1 to 108.100.255.254108.100.255.25565,534
102108.101.0.0/16108.101.0.1 to 108.101.255.254108.101.255.25565,534
103108.102.0.0/16108.102.0.1 to 108.102.255.254108.102.255.25565,534
104108.103.0.0/16108.103.0.1 to 108.103.255.254108.103.255.25565,534
105108.104.0.0/16108.104.0.1 to 108.104.255.254108.104.255.25565,534
106108.105.0.0/16108.105.0.1 to 108.105.255.254108.105.255.25565,534
107108.106.0.0/16108.106.0.1 to 108.106.255.254108.106.255.25565,534
108108.107.0.0/16108.107.0.1 to 108.107.255.254108.107.255.25565,534
109108.108.0.0/16108.108.0.1 to 108.108.255.254108.108.255.25565,534
110108.109.0.0/16108.109.0.1 to 108.109.255.254108.109.255.25565,534
111108.110.0.0/16108.110.0.1 to 108.110.255.254108.110.255.25565,534
112108.111.0.0/16108.111.0.1 to 108.111.255.254108.111.255.25565,534
113108.112.0.0/16108.112.0.1 to 108.112.255.254108.112.255.25565,534
114108.113.0.0/16108.113.0.1 to 108.113.255.254108.113.255.25565,534
115108.114.0.0/16108.114.0.1 to 108.114.255.254108.114.255.25565,534
116108.115.0.0/16108.115.0.1 to 108.115.255.254108.115.255.25565,534
117108.116.0.0/16108.116.0.1 to 108.116.255.254108.116.255.25565,534
118108.117.0.0/16108.117.0.1 to 108.117.255.254108.117.255.25565,534
119108.118.0.0/16108.118.0.1 to 108.118.255.254108.118.255.25565,534
120108.119.0.0/16108.119.0.1 to 108.119.255.254108.119.255.25565,534
121108.120.0.0/16108.120.0.1 to 108.120.255.254108.120.255.25565,534
122108.121.0.0/16108.121.0.1 to 108.121.255.254108.121.255.25565,534
123108.122.0.0/16108.122.0.1 to 108.122.255.254108.122.255.25565,534
124108.123.0.0/16108.123.0.1 to 108.123.255.254108.123.255.25565,534
125108.124.0.0/16108.124.0.1 to 108.124.255.254108.124.255.25565,534
126108.125.0.0/16108.125.0.1 to 108.125.255.254108.125.255.25565,534
127108.126.0.0/16108.126.0.1 to 108.126.255.254108.126.255.25565,534
128108.127.0.0/16108.127.0.1 to 108.127.255.254108.127.255.25565,534
129108.128.0.0/16108.128.0.1 to 108.128.255.254108.128.255.25565,534
130108.129.0.0/16108.129.0.1 to 108.129.255.254108.129.255.25565,534
131108.130.0.0/16108.130.0.1 to 108.130.255.254108.130.255.25565,534
132108.131.0.0/16108.131.0.1 to 108.131.255.254108.131.255.25565,534
133108.132.0.0/16108.132.0.1 to 108.132.255.254108.132.255.25565,534
134108.133.0.0/16108.133.0.1 to 108.133.255.254108.133.255.25565,534
135108.134.0.0/16108.134.0.1 to 108.134.255.254108.134.255.25565,534
136108.135.0.0/16108.135.0.1 to 108.135.255.254108.135.255.25565,534
137108.136.0.0/16108.136.0.1 to 108.136.255.254108.136.255.25565,534
138108.137.0.0/16108.137.0.1 to 108.137.255.254108.137.255.25565,534
139108.138.0.0/16108.138.0.1 to 108.138.255.254108.138.255.25565,534
140108.139.0.0/16108.139.0.1 to 108.139.255.254108.139.255.25565,534
141108.140.0.0/16108.140.0.1 to 108.140.255.254108.140.255.25565,534
142108.141.0.0/16108.141.0.1 to 108.141.255.254108.141.255.25565,534
143108.142.0.0/16108.142.0.1 to 108.142.255.254108.142.255.25565,534
144108.143.0.0/16108.143.0.1 to 108.143.255.254108.143.255.25565,534
145108.144.0.0/16108.144.0.1 to 108.144.255.254108.144.255.25565,534
146108.145.0.0/16108.145.0.1 to 108.145.255.254108.145.255.25565,534
147108.146.0.0/16108.146.0.1 to 108.146.255.254108.146.255.25565,534
148108.147.0.0/16108.147.0.1 to 108.147.255.254108.147.255.25565,534
149108.148.0.0/16108.148.0.1 to 108.148.255.254108.148.255.25565,534
150108.149.0.0/16108.149.0.1 to 108.149.255.254108.149.255.25565,534
151108.150.0.0/16108.150.0.1 to 108.150.255.254108.150.255.25565,534
152108.151.0.0/16108.151.0.1 to 108.151.255.254108.151.255.25565,534
153108.152.0.0/16108.152.0.1 to 108.152.255.254108.152.255.25565,534
154108.153.0.0/16108.153.0.1 to 108.153.255.254108.153.255.25565,534
155108.154.0.0/16108.154.0.1 to 108.154.255.254108.154.255.25565,534
156108.155.0.0/16108.155.0.1 to 108.155.255.254108.155.255.25565,534
157108.156.0.0/16108.156.0.1 to 108.156.255.254108.156.255.25565,534
158108.157.0.0/16108.157.0.1 to 108.157.255.254108.157.255.25565,534
159108.158.0.0/16108.158.0.1 to 108.158.255.254108.158.255.25565,534
160108.159.0.0/16108.159.0.1 to 108.159.255.254108.159.255.25565,534
161108.160.0.0/16108.160.0.1 to 108.160.255.254108.160.255.25565,534
162108.161.0.0/16108.161.0.1 to 108.161.255.254108.161.255.25565,534
163108.162.0.0/16108.162.0.1 to 108.162.255.254108.162.255.25565,534
164108.163.0.0/16108.163.0.1 to 108.163.255.254108.163.255.25565,534
165108.164.0.0/16108.164.0.1 to 108.164.255.254108.164.255.25565,534
166108.165.0.0/16108.165.0.1 to 108.165.255.254108.165.255.25565,534
167108.166.0.0/16108.166.0.1 to 108.166.255.254108.166.255.25565,534
168108.167.0.0/16108.167.0.1 to 108.167.255.254108.167.255.25565,534
169108.168.0.0/16108.168.0.1 to 108.168.255.254108.168.255.25565,534
170108.169.0.0/16108.169.0.1 to 108.169.255.254108.169.255.25565,534
171108.170.0.0/16108.170.0.1 to 108.170.255.254108.170.255.25565,534
172108.171.0.0/16108.171.0.1 to 108.171.255.254108.171.255.25565,534
173108.172.0.0/16108.172.0.1 to 108.172.255.254108.172.255.25565,534
174108.173.0.0/16108.173.0.1 to 108.173.255.254108.173.255.25565,534
175108.174.0.0/16108.174.0.1 to 108.174.255.254108.174.255.25565,534
176108.175.0.0/16108.175.0.1 to 108.175.255.254108.175.255.25565,534
177108.176.0.0/16108.176.0.1 to 108.176.255.254108.176.255.25565,534
178108.177.0.0/16108.177.0.1 to 108.177.255.254108.177.255.25565,534
179108.178.0.0/16108.178.0.1 to 108.178.255.254108.178.255.25565,534
180108.179.0.0/16108.179.0.1 to 108.179.255.254108.179.255.25565,534
181108.180.0.0/16108.180.0.1 to 108.180.255.254108.180.255.25565,534
182108.181.0.0/16108.181.0.1 to 108.181.255.254108.181.255.25565,534
183108.182.0.0/16108.182.0.1 to 108.182.255.254108.182.255.25565,534
184108.183.0.0/16108.183.0.1 to 108.183.255.254108.183.255.25565,534
185108.184.0.0/16108.184.0.1 to 108.184.255.254108.184.255.25565,534
186108.185.0.0/16108.185.0.1 to 108.185.255.254108.185.255.25565,534
187108.186.0.0/16108.186.0.1 to 108.186.255.254108.186.255.25565,534
188108.187.0.0/16108.187.0.1 to 108.187.255.254108.187.255.25565,534
189108.188.0.0/16108.188.0.1 to 108.188.255.254108.188.255.25565,534
190108.189.0.0/16108.189.0.1 to 108.189.255.254108.189.255.25565,534
191108.190.0.0/16108.190.0.1 to 108.190.255.254108.190.255.25565,534
192108.191.0.0/16108.191.0.1 to 108.191.255.254108.191.255.25565,534
193108.192.0.0/16108.192.0.1 to 108.192.255.254108.192.255.25565,534
194108.193.0.0/16108.193.0.1 to 108.193.255.254108.193.255.25565,534
195108.194.0.0/16108.194.0.1 to 108.194.255.254108.194.255.25565,534
196108.195.0.0/16108.195.0.1 to 108.195.255.254108.195.255.25565,534
197108.196.0.0/16108.196.0.1 to 108.196.255.254108.196.255.25565,534
198108.197.0.0/16108.197.0.1 to 108.197.255.254108.197.255.25565,534
199108.198.0.0/16108.198.0.1 to 108.198.255.254108.198.255.25565,534
200108.199.0.0/16108.199.0.1 to 108.199.255.254108.199.255.25565,534
201108.200.0.0/16108.200.0.1 to 108.200.255.254108.200.255.25565,534
202108.201.0.0/16108.201.0.1 to 108.201.255.254108.201.255.25565,534
203108.202.0.0/16108.202.0.1 to 108.202.255.254108.202.255.25565,534
204108.203.0.0/16108.203.0.1 to 108.203.255.254108.203.255.25565,534
205108.204.0.0/16108.204.0.1 to 108.204.255.254108.204.255.25565,534
206108.205.0.0/16108.205.0.1 to 108.205.255.254108.205.255.25565,534
207108.206.0.0/16108.206.0.1 to 108.206.255.254108.206.255.25565,534
208108.207.0.0/16108.207.0.1 to 108.207.255.254108.207.255.25565,534
209108.208.0.0/16108.208.0.1 to 108.208.255.254108.208.255.25565,534
210108.209.0.0/16108.209.0.1 to 108.209.255.254108.209.255.25565,534
211108.210.0.0/16108.210.0.1 to 108.210.255.254108.210.255.25565,534
212108.211.0.0/16108.211.0.1 to 108.211.255.254108.211.255.25565,534
213108.212.0.0/16108.212.0.1 to 108.212.255.254108.212.255.25565,534
214108.213.0.0/16108.213.0.1 to 108.213.255.254108.213.255.25565,534
215108.214.0.0/16108.214.0.1 to 108.214.255.254108.214.255.25565,534
216108.215.0.0/16108.215.0.1 to 108.215.255.254108.215.255.25565,534
217108.216.0.0/16108.216.0.1 to 108.216.255.254108.216.255.25565,534
218108.217.0.0/16108.217.0.1 to 108.217.255.254108.217.255.25565,534
219108.218.0.0/16108.218.0.1 to 108.218.255.254108.218.255.25565,534
220108.219.0.0/16108.219.0.1 to 108.219.255.254108.219.255.25565,534
221108.220.0.0/16108.220.0.1 to 108.220.255.254108.220.255.25565,534
222108.221.0.0/16108.221.0.1 to 108.221.255.254108.221.255.25565,534
223108.222.0.0/16108.222.0.1 to 108.222.255.254108.222.255.25565,534
224108.223.0.0/16108.223.0.1 to 108.223.255.254108.223.255.25565,534
225108.224.0.0/16108.224.0.1 to 108.224.255.254108.224.255.25565,534
226108.225.0.0/16108.225.0.1 to 108.225.255.254108.225.255.25565,534
227108.226.0.0/16108.226.0.1 to 108.226.255.254108.226.255.25565,534
228108.227.0.0/16108.227.0.1 to 108.227.255.254108.227.255.25565,534
229108.228.0.0/16108.228.0.1 to 108.228.255.254108.228.255.25565,534
230108.229.0.0/16108.229.0.1 to 108.229.255.254108.229.255.25565,534
231108.230.0.0/16108.230.0.1 to 108.230.255.254108.230.255.25565,534
232108.231.0.0/16108.231.0.1 to 108.231.255.254108.231.255.25565,534
233108.232.0.0/16108.232.0.1 to 108.232.255.254108.232.255.25565,534
234108.233.0.0/16108.233.0.1 to 108.233.255.254108.233.255.25565,534
235108.234.0.0/16108.234.0.1 to 108.234.255.254108.234.255.25565,534
236108.235.0.0/16108.235.0.1 to 108.235.255.254108.235.255.25565,534
237108.236.0.0/16108.236.0.1 to 108.236.255.254108.236.255.25565,534
238108.237.0.0/16108.237.0.1 to 108.237.255.254108.237.255.25565,534
239108.238.0.0/16108.238.0.1 to 108.238.255.254108.238.255.25565,534
240108.239.0.0/16108.239.0.1 to 108.239.255.254108.239.255.25565,534
241108.240.0.0/16108.240.0.1 to 108.240.255.254108.240.255.25565,534
242108.241.0.0/16108.241.0.1 to 108.241.255.254108.241.255.25565,534
243108.242.0.0/16108.242.0.1 to 108.242.255.254108.242.255.25565,534
244108.243.0.0/16108.243.0.1 to 108.243.255.254108.243.255.25565,534
245108.244.0.0/16108.244.0.1 to 108.244.255.254108.244.255.25565,534
246108.245.0.0/16108.245.0.1 to 108.245.255.254108.245.255.25565,534
247108.246.0.0/16108.246.0.1 to 108.246.255.254108.246.255.25565,534
248108.247.0.0/16108.247.0.1 to 108.247.255.254108.247.255.25565,534
249108.248.0.0/16108.248.0.1 to 108.248.255.254108.248.255.25565,534
250108.249.0.0/16108.249.0.1 to 108.249.255.254108.249.255.25565,534
251108.250.0.0/16108.250.0.1 to 108.250.255.254108.250.255.25565,534
252108.251.0.0/16108.251.0.1 to 108.251.255.254108.251.255.25565,534
253108.252.0.0/16108.252.0.1 to 108.252.255.254108.252.255.25565,534
254108.253.0.0/16108.253.0.1 to 108.253.255.254108.253.255.25565,534
255108.254.0.0/16108.254.0.1 to 108.254.255.254108.254.255.25565,534
256108.255.0.0/16108.255.0.1 to 108.255.255.254108.255.255.25565,534

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.