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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.

Network131.88.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
131.88.0.0
Broadcast address
131.91.255.255
First usable
131.88.0.1
Last usable
131.91.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
B (default /16)
As numbers
Hex 83580000 · Integer 2203582464 to 2203844607
Reverse DNS zones
88.131.in-addr.arpa
89.131.in-addr.arpa
90.131.in-addr.arpa
91.131.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
Address10000011.01011000.00000000.00000000131.88.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10000011.01011000.00000000.00000000131.88.0.0
Broadcast10000011.01011011.11111111.11111111131.91.255.255
Split into smaller subnets/23

131.88.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1131.88.0.0/23131.88.0.1 to 131.88.1.254131.88.1.255510
2131.88.2.0/23131.88.2.1 to 131.88.3.254131.88.3.255510
3131.88.4.0/23131.88.4.1 to 131.88.5.254131.88.5.255510
4131.88.6.0/23131.88.6.1 to 131.88.7.254131.88.7.255510
5131.88.8.0/23131.88.8.1 to 131.88.9.254131.88.9.255510
6131.88.10.0/23131.88.10.1 to 131.88.11.254131.88.11.255510
7131.88.12.0/23131.88.12.1 to 131.88.13.254131.88.13.255510
8131.88.14.0/23131.88.14.1 to 131.88.15.254131.88.15.255510
9131.88.16.0/23131.88.16.1 to 131.88.17.254131.88.17.255510
10131.88.18.0/23131.88.18.1 to 131.88.19.254131.88.19.255510
11131.88.20.0/23131.88.20.1 to 131.88.21.254131.88.21.255510
12131.88.22.0/23131.88.22.1 to 131.88.23.254131.88.23.255510
13131.88.24.0/23131.88.24.1 to 131.88.25.254131.88.25.255510
14131.88.26.0/23131.88.26.1 to 131.88.27.254131.88.27.255510
15131.88.28.0/23131.88.28.1 to 131.88.29.254131.88.29.255510
16131.88.30.0/23131.88.30.1 to 131.88.31.254131.88.31.255510
17131.88.32.0/23131.88.32.1 to 131.88.33.254131.88.33.255510
18131.88.34.0/23131.88.34.1 to 131.88.35.254131.88.35.255510
19131.88.36.0/23131.88.36.1 to 131.88.37.254131.88.37.255510
20131.88.38.0/23131.88.38.1 to 131.88.39.254131.88.39.255510
21131.88.40.0/23131.88.40.1 to 131.88.41.254131.88.41.255510
22131.88.42.0/23131.88.42.1 to 131.88.43.254131.88.43.255510
23131.88.44.0/23131.88.44.1 to 131.88.45.254131.88.45.255510
24131.88.46.0/23131.88.46.1 to 131.88.47.254131.88.47.255510
25131.88.48.0/23131.88.48.1 to 131.88.49.254131.88.49.255510
26131.88.50.0/23131.88.50.1 to 131.88.51.254131.88.51.255510
27131.88.52.0/23131.88.52.1 to 131.88.53.254131.88.53.255510
28131.88.54.0/23131.88.54.1 to 131.88.55.254131.88.55.255510
29131.88.56.0/23131.88.56.1 to 131.88.57.254131.88.57.255510
30131.88.58.0/23131.88.58.1 to 131.88.59.254131.88.59.255510
31131.88.60.0/23131.88.60.1 to 131.88.61.254131.88.61.255510
32131.88.62.0/23131.88.62.1 to 131.88.63.254131.88.63.255510
33131.88.64.0/23131.88.64.1 to 131.88.65.254131.88.65.255510
34131.88.66.0/23131.88.66.1 to 131.88.67.254131.88.67.255510
35131.88.68.0/23131.88.68.1 to 131.88.69.254131.88.69.255510
36131.88.70.0/23131.88.70.1 to 131.88.71.254131.88.71.255510
37131.88.72.0/23131.88.72.1 to 131.88.73.254131.88.73.255510
38131.88.74.0/23131.88.74.1 to 131.88.75.254131.88.75.255510
39131.88.76.0/23131.88.76.1 to 131.88.77.254131.88.77.255510
40131.88.78.0/23131.88.78.1 to 131.88.79.254131.88.79.255510
41131.88.80.0/23131.88.80.1 to 131.88.81.254131.88.81.255510
42131.88.82.0/23131.88.82.1 to 131.88.83.254131.88.83.255510
43131.88.84.0/23131.88.84.1 to 131.88.85.254131.88.85.255510
44131.88.86.0/23131.88.86.1 to 131.88.87.254131.88.87.255510
45131.88.88.0/23131.88.88.1 to 131.88.89.254131.88.89.255510
46131.88.90.0/23131.88.90.1 to 131.88.91.254131.88.91.255510
47131.88.92.0/23131.88.92.1 to 131.88.93.254131.88.93.255510
48131.88.94.0/23131.88.94.1 to 131.88.95.254131.88.95.255510
49131.88.96.0/23131.88.96.1 to 131.88.97.254131.88.97.255510
50131.88.98.0/23131.88.98.1 to 131.88.99.254131.88.99.255510
51131.88.100.0/23131.88.100.1 to 131.88.101.254131.88.101.255510
52131.88.102.0/23131.88.102.1 to 131.88.103.254131.88.103.255510
53131.88.104.0/23131.88.104.1 to 131.88.105.254131.88.105.255510
54131.88.106.0/23131.88.106.1 to 131.88.107.254131.88.107.255510
55131.88.108.0/23131.88.108.1 to 131.88.109.254131.88.109.255510
56131.88.110.0/23131.88.110.1 to 131.88.111.254131.88.111.255510
57131.88.112.0/23131.88.112.1 to 131.88.113.254131.88.113.255510
58131.88.114.0/23131.88.114.1 to 131.88.115.254131.88.115.255510
59131.88.116.0/23131.88.116.1 to 131.88.117.254131.88.117.255510
60131.88.118.0/23131.88.118.1 to 131.88.119.254131.88.119.255510
61131.88.120.0/23131.88.120.1 to 131.88.121.254131.88.121.255510
62131.88.122.0/23131.88.122.1 to 131.88.123.254131.88.123.255510
63131.88.124.0/23131.88.124.1 to 131.88.125.254131.88.125.255510
64131.88.126.0/23131.88.126.1 to 131.88.127.254131.88.127.255510
65131.88.128.0/23131.88.128.1 to 131.88.129.254131.88.129.255510
66131.88.130.0/23131.88.130.1 to 131.88.131.254131.88.131.255510
67131.88.132.0/23131.88.132.1 to 131.88.133.254131.88.133.255510
68131.88.134.0/23131.88.134.1 to 131.88.135.254131.88.135.255510
69131.88.136.0/23131.88.136.1 to 131.88.137.254131.88.137.255510
70131.88.138.0/23131.88.138.1 to 131.88.139.254131.88.139.255510
71131.88.140.0/23131.88.140.1 to 131.88.141.254131.88.141.255510
72131.88.142.0/23131.88.142.1 to 131.88.143.254131.88.143.255510
73131.88.144.0/23131.88.144.1 to 131.88.145.254131.88.145.255510
74131.88.146.0/23131.88.146.1 to 131.88.147.254131.88.147.255510
75131.88.148.0/23131.88.148.1 to 131.88.149.254131.88.149.255510
76131.88.150.0/23131.88.150.1 to 131.88.151.254131.88.151.255510
77131.88.152.0/23131.88.152.1 to 131.88.153.254131.88.153.255510
78131.88.154.0/23131.88.154.1 to 131.88.155.254131.88.155.255510
79131.88.156.0/23131.88.156.1 to 131.88.157.254131.88.157.255510
80131.88.158.0/23131.88.158.1 to 131.88.159.254131.88.159.255510
81131.88.160.0/23131.88.160.1 to 131.88.161.254131.88.161.255510
82131.88.162.0/23131.88.162.1 to 131.88.163.254131.88.163.255510
83131.88.164.0/23131.88.164.1 to 131.88.165.254131.88.165.255510
84131.88.166.0/23131.88.166.1 to 131.88.167.254131.88.167.255510
85131.88.168.0/23131.88.168.1 to 131.88.169.254131.88.169.255510
86131.88.170.0/23131.88.170.1 to 131.88.171.254131.88.171.255510
87131.88.172.0/23131.88.172.1 to 131.88.173.254131.88.173.255510
88131.88.174.0/23131.88.174.1 to 131.88.175.254131.88.175.255510
89131.88.176.0/23131.88.176.1 to 131.88.177.254131.88.177.255510
90131.88.178.0/23131.88.178.1 to 131.88.179.254131.88.179.255510
91131.88.180.0/23131.88.180.1 to 131.88.181.254131.88.181.255510
92131.88.182.0/23131.88.182.1 to 131.88.183.254131.88.183.255510
93131.88.184.0/23131.88.184.1 to 131.88.185.254131.88.185.255510
94131.88.186.0/23131.88.186.1 to 131.88.187.254131.88.187.255510
95131.88.188.0/23131.88.188.1 to 131.88.189.254131.88.189.255510
96131.88.190.0/23131.88.190.1 to 131.88.191.254131.88.191.255510
97131.88.192.0/23131.88.192.1 to 131.88.193.254131.88.193.255510
98131.88.194.0/23131.88.194.1 to 131.88.195.254131.88.195.255510
99131.88.196.0/23131.88.196.1 to 131.88.197.254131.88.197.255510
100131.88.198.0/23131.88.198.1 to 131.88.199.254131.88.199.255510
101131.88.200.0/23131.88.200.1 to 131.88.201.254131.88.201.255510
102131.88.202.0/23131.88.202.1 to 131.88.203.254131.88.203.255510
103131.88.204.0/23131.88.204.1 to 131.88.205.254131.88.205.255510
104131.88.206.0/23131.88.206.1 to 131.88.207.254131.88.207.255510
105131.88.208.0/23131.88.208.1 to 131.88.209.254131.88.209.255510
106131.88.210.0/23131.88.210.1 to 131.88.211.254131.88.211.255510
107131.88.212.0/23131.88.212.1 to 131.88.213.254131.88.213.255510
108131.88.214.0/23131.88.214.1 to 131.88.215.254131.88.215.255510
109131.88.216.0/23131.88.216.1 to 131.88.217.254131.88.217.255510
110131.88.218.0/23131.88.218.1 to 131.88.219.254131.88.219.255510
111131.88.220.0/23131.88.220.1 to 131.88.221.254131.88.221.255510
112131.88.222.0/23131.88.222.1 to 131.88.223.254131.88.223.255510
113131.88.224.0/23131.88.224.1 to 131.88.225.254131.88.225.255510
114131.88.226.0/23131.88.226.1 to 131.88.227.254131.88.227.255510
115131.88.228.0/23131.88.228.1 to 131.88.229.254131.88.229.255510
116131.88.230.0/23131.88.230.1 to 131.88.231.254131.88.231.255510
117131.88.232.0/23131.88.232.1 to 131.88.233.254131.88.233.255510
118131.88.234.0/23131.88.234.1 to 131.88.235.254131.88.235.255510
119131.88.236.0/23131.88.236.1 to 131.88.237.254131.88.237.255510
120131.88.238.0/23131.88.238.1 to 131.88.239.254131.88.239.255510
121131.88.240.0/23131.88.240.1 to 131.88.241.254131.88.241.255510
122131.88.242.0/23131.88.242.1 to 131.88.243.254131.88.243.255510
123131.88.244.0/23131.88.244.1 to 131.88.245.254131.88.245.255510
124131.88.246.0/23131.88.246.1 to 131.88.247.254131.88.247.255510
125131.88.248.0/23131.88.248.1 to 131.88.249.254131.88.249.255510
126131.88.250.0/23131.88.250.1 to 131.88.251.254131.88.251.255510
127131.88.252.0/23131.88.252.1 to 131.88.253.254131.88.253.255510
128131.88.254.0/23131.88.254.1 to 131.88.255.254131.88.255.255510
129131.89.0.0/23131.89.0.1 to 131.89.1.254131.89.1.255510
130131.89.2.0/23131.89.2.1 to 131.89.3.254131.89.3.255510
131131.89.4.0/23131.89.4.1 to 131.89.5.254131.89.5.255510
132131.89.6.0/23131.89.6.1 to 131.89.7.254131.89.7.255510
133131.89.8.0/23131.89.8.1 to 131.89.9.254131.89.9.255510
134131.89.10.0/23131.89.10.1 to 131.89.11.254131.89.11.255510
135131.89.12.0/23131.89.12.1 to 131.89.13.254131.89.13.255510
136131.89.14.0/23131.89.14.1 to 131.89.15.254131.89.15.255510
137131.89.16.0/23131.89.16.1 to 131.89.17.254131.89.17.255510
138131.89.18.0/23131.89.18.1 to 131.89.19.254131.89.19.255510
139131.89.20.0/23131.89.20.1 to 131.89.21.254131.89.21.255510
140131.89.22.0/23131.89.22.1 to 131.89.23.254131.89.23.255510
141131.89.24.0/23131.89.24.1 to 131.89.25.254131.89.25.255510
142131.89.26.0/23131.89.26.1 to 131.89.27.254131.89.27.255510
143131.89.28.0/23131.89.28.1 to 131.89.29.254131.89.29.255510
144131.89.30.0/23131.89.30.1 to 131.89.31.254131.89.31.255510
145131.89.32.0/23131.89.32.1 to 131.89.33.254131.89.33.255510
146131.89.34.0/23131.89.34.1 to 131.89.35.254131.89.35.255510
147131.89.36.0/23131.89.36.1 to 131.89.37.254131.89.37.255510
148131.89.38.0/23131.89.38.1 to 131.89.39.254131.89.39.255510
149131.89.40.0/23131.89.40.1 to 131.89.41.254131.89.41.255510
150131.89.42.0/23131.89.42.1 to 131.89.43.254131.89.43.255510
151131.89.44.0/23131.89.44.1 to 131.89.45.254131.89.45.255510
152131.89.46.0/23131.89.46.1 to 131.89.47.254131.89.47.255510
153131.89.48.0/23131.89.48.1 to 131.89.49.254131.89.49.255510
154131.89.50.0/23131.89.50.1 to 131.89.51.254131.89.51.255510
155131.89.52.0/23131.89.52.1 to 131.89.53.254131.89.53.255510
156131.89.54.0/23131.89.54.1 to 131.89.55.254131.89.55.255510
157131.89.56.0/23131.89.56.1 to 131.89.57.254131.89.57.255510
158131.89.58.0/23131.89.58.1 to 131.89.59.254131.89.59.255510
159131.89.60.0/23131.89.60.1 to 131.89.61.254131.89.61.255510
160131.89.62.0/23131.89.62.1 to 131.89.63.254131.89.63.255510
161131.89.64.0/23131.89.64.1 to 131.89.65.254131.89.65.255510
162131.89.66.0/23131.89.66.1 to 131.89.67.254131.89.67.255510
163131.89.68.0/23131.89.68.1 to 131.89.69.254131.89.69.255510
164131.89.70.0/23131.89.70.1 to 131.89.71.254131.89.71.255510
165131.89.72.0/23131.89.72.1 to 131.89.73.254131.89.73.255510
166131.89.74.0/23131.89.74.1 to 131.89.75.254131.89.75.255510
167131.89.76.0/23131.89.76.1 to 131.89.77.254131.89.77.255510
168131.89.78.0/23131.89.78.1 to 131.89.79.254131.89.79.255510
169131.89.80.0/23131.89.80.1 to 131.89.81.254131.89.81.255510
170131.89.82.0/23131.89.82.1 to 131.89.83.254131.89.83.255510
171131.89.84.0/23131.89.84.1 to 131.89.85.254131.89.85.255510
172131.89.86.0/23131.89.86.1 to 131.89.87.254131.89.87.255510
173131.89.88.0/23131.89.88.1 to 131.89.89.254131.89.89.255510
174131.89.90.0/23131.89.90.1 to 131.89.91.254131.89.91.255510
175131.89.92.0/23131.89.92.1 to 131.89.93.254131.89.93.255510
176131.89.94.0/23131.89.94.1 to 131.89.95.254131.89.95.255510
177131.89.96.0/23131.89.96.1 to 131.89.97.254131.89.97.255510
178131.89.98.0/23131.89.98.1 to 131.89.99.254131.89.99.255510
179131.89.100.0/23131.89.100.1 to 131.89.101.254131.89.101.255510
180131.89.102.0/23131.89.102.1 to 131.89.103.254131.89.103.255510
181131.89.104.0/23131.89.104.1 to 131.89.105.254131.89.105.255510
182131.89.106.0/23131.89.106.1 to 131.89.107.254131.89.107.255510
183131.89.108.0/23131.89.108.1 to 131.89.109.254131.89.109.255510
184131.89.110.0/23131.89.110.1 to 131.89.111.254131.89.111.255510
185131.89.112.0/23131.89.112.1 to 131.89.113.254131.89.113.255510
186131.89.114.0/23131.89.114.1 to 131.89.115.254131.89.115.255510
187131.89.116.0/23131.89.116.1 to 131.89.117.254131.89.117.255510
188131.89.118.0/23131.89.118.1 to 131.89.119.254131.89.119.255510
189131.89.120.0/23131.89.120.1 to 131.89.121.254131.89.121.255510
190131.89.122.0/23131.89.122.1 to 131.89.123.254131.89.123.255510
191131.89.124.0/23131.89.124.1 to 131.89.125.254131.89.125.255510
192131.89.126.0/23131.89.126.1 to 131.89.127.254131.89.127.255510
193131.89.128.0/23131.89.128.1 to 131.89.129.254131.89.129.255510
194131.89.130.0/23131.89.130.1 to 131.89.131.254131.89.131.255510
195131.89.132.0/23131.89.132.1 to 131.89.133.254131.89.133.255510
196131.89.134.0/23131.89.134.1 to 131.89.135.254131.89.135.255510
197131.89.136.0/23131.89.136.1 to 131.89.137.254131.89.137.255510
198131.89.138.0/23131.89.138.1 to 131.89.139.254131.89.139.255510
199131.89.140.0/23131.89.140.1 to 131.89.141.254131.89.141.255510
200131.89.142.0/23131.89.142.1 to 131.89.143.254131.89.143.255510
201131.89.144.0/23131.89.144.1 to 131.89.145.254131.89.145.255510
202131.89.146.0/23131.89.146.1 to 131.89.147.254131.89.147.255510
203131.89.148.0/23131.89.148.1 to 131.89.149.254131.89.149.255510
204131.89.150.0/23131.89.150.1 to 131.89.151.254131.89.151.255510
205131.89.152.0/23131.89.152.1 to 131.89.153.254131.89.153.255510
206131.89.154.0/23131.89.154.1 to 131.89.155.254131.89.155.255510
207131.89.156.0/23131.89.156.1 to 131.89.157.254131.89.157.255510
208131.89.158.0/23131.89.158.1 to 131.89.159.254131.89.159.255510
209131.89.160.0/23131.89.160.1 to 131.89.161.254131.89.161.255510
210131.89.162.0/23131.89.162.1 to 131.89.163.254131.89.163.255510
211131.89.164.0/23131.89.164.1 to 131.89.165.254131.89.165.255510
212131.89.166.0/23131.89.166.1 to 131.89.167.254131.89.167.255510
213131.89.168.0/23131.89.168.1 to 131.89.169.254131.89.169.255510
214131.89.170.0/23131.89.170.1 to 131.89.171.254131.89.171.255510
215131.89.172.0/23131.89.172.1 to 131.89.173.254131.89.173.255510
216131.89.174.0/23131.89.174.1 to 131.89.175.254131.89.175.255510
217131.89.176.0/23131.89.176.1 to 131.89.177.254131.89.177.255510
218131.89.178.0/23131.89.178.1 to 131.89.179.254131.89.179.255510
219131.89.180.0/23131.89.180.1 to 131.89.181.254131.89.181.255510
220131.89.182.0/23131.89.182.1 to 131.89.183.254131.89.183.255510
221131.89.184.0/23131.89.184.1 to 131.89.185.254131.89.185.255510
222131.89.186.0/23131.89.186.1 to 131.89.187.254131.89.187.255510
223131.89.188.0/23131.89.188.1 to 131.89.189.254131.89.189.255510
224131.89.190.0/23131.89.190.1 to 131.89.191.254131.89.191.255510
225131.89.192.0/23131.89.192.1 to 131.89.193.254131.89.193.255510
226131.89.194.0/23131.89.194.1 to 131.89.195.254131.89.195.255510
227131.89.196.0/23131.89.196.1 to 131.89.197.254131.89.197.255510
228131.89.198.0/23131.89.198.1 to 131.89.199.254131.89.199.255510
229131.89.200.0/23131.89.200.1 to 131.89.201.254131.89.201.255510
230131.89.202.0/23131.89.202.1 to 131.89.203.254131.89.203.255510
231131.89.204.0/23131.89.204.1 to 131.89.205.254131.89.205.255510
232131.89.206.0/23131.89.206.1 to 131.89.207.254131.89.207.255510
233131.89.208.0/23131.89.208.1 to 131.89.209.254131.89.209.255510
234131.89.210.0/23131.89.210.1 to 131.89.211.254131.89.211.255510
235131.89.212.0/23131.89.212.1 to 131.89.213.254131.89.213.255510
236131.89.214.0/23131.89.214.1 to 131.89.215.254131.89.215.255510
237131.89.216.0/23131.89.216.1 to 131.89.217.254131.89.217.255510
238131.89.218.0/23131.89.218.1 to 131.89.219.254131.89.219.255510
239131.89.220.0/23131.89.220.1 to 131.89.221.254131.89.221.255510
240131.89.222.0/23131.89.222.1 to 131.89.223.254131.89.223.255510
241131.89.224.0/23131.89.224.1 to 131.89.225.254131.89.225.255510
242131.89.226.0/23131.89.226.1 to 131.89.227.254131.89.227.255510
243131.89.228.0/23131.89.228.1 to 131.89.229.254131.89.229.255510
244131.89.230.0/23131.89.230.1 to 131.89.231.254131.89.231.255510
245131.89.232.0/23131.89.232.1 to 131.89.233.254131.89.233.255510
246131.89.234.0/23131.89.234.1 to 131.89.235.254131.89.235.255510
247131.89.236.0/23131.89.236.1 to 131.89.237.254131.89.237.255510
248131.89.238.0/23131.89.238.1 to 131.89.239.254131.89.239.255510
249131.89.240.0/23131.89.240.1 to 131.89.241.254131.89.241.255510
250131.89.242.0/23131.89.242.1 to 131.89.243.254131.89.243.255510
251131.89.244.0/23131.89.244.1 to 131.89.245.254131.89.245.255510
252131.89.246.0/23131.89.246.1 to 131.89.247.254131.89.247.255510
253131.89.248.0/23131.89.248.1 to 131.89.249.254131.89.249.255510
254131.89.250.0/23131.89.250.1 to 131.89.251.254131.89.251.255510
255131.89.252.0/23131.89.252.1 to 131.89.253.254131.89.253.255510
256131.89.254.0/23131.89.254.1 to 131.89.255.254131.89.255.255510

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