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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.

Network130.136.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
130.136.0.0
Broadcast address
130.143.255.255
First usable
130.136.0.1
Last usable
130.143.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
B (default /16)
As numbers
Hex 82880000 · Integer 2189950976 to 2190475263
Reverse DNS zones
136.130.in-addr.arpa
137.130.in-addr.arpa
138.130.in-addr.arpa
139.130.in-addr.arpa
140.130.in-addr.arpa
141.130.in-addr.arpa
142.130.in-addr.arpa
143.130.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10000010.10001000.00000000.00000000130.136.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network10000010.10001000.00000000.00000000130.136.0.0
Broadcast10000010.10001111.11111111.11111111130.143.255.255
Split into smaller subnets/24
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

130.136.0.0/13 makes 2,048 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1130.136.0.0/24130.136.0.1 to 130.136.0.254130.136.0.255254
2130.136.1.0/24130.136.1.1 to 130.136.1.254130.136.1.255254
3130.136.2.0/24130.136.2.1 to 130.136.2.254130.136.2.255254
4130.136.3.0/24130.136.3.1 to 130.136.3.254130.136.3.255254
5130.136.4.0/24130.136.4.1 to 130.136.4.254130.136.4.255254
6130.136.5.0/24130.136.5.1 to 130.136.5.254130.136.5.255254
7130.136.6.0/24130.136.6.1 to 130.136.6.254130.136.6.255254
8130.136.7.0/24130.136.7.1 to 130.136.7.254130.136.7.255254
9130.136.8.0/24130.136.8.1 to 130.136.8.254130.136.8.255254
10130.136.9.0/24130.136.9.1 to 130.136.9.254130.136.9.255254
11130.136.10.0/24130.136.10.1 to 130.136.10.254130.136.10.255254
12130.136.11.0/24130.136.11.1 to 130.136.11.254130.136.11.255254
13130.136.12.0/24130.136.12.1 to 130.136.12.254130.136.12.255254
14130.136.13.0/24130.136.13.1 to 130.136.13.254130.136.13.255254
15130.136.14.0/24130.136.14.1 to 130.136.14.254130.136.14.255254
16130.136.15.0/24130.136.15.1 to 130.136.15.254130.136.15.255254
17130.136.16.0/24130.136.16.1 to 130.136.16.254130.136.16.255254
18130.136.17.0/24130.136.17.1 to 130.136.17.254130.136.17.255254
19130.136.18.0/24130.136.18.1 to 130.136.18.254130.136.18.255254
20130.136.19.0/24130.136.19.1 to 130.136.19.254130.136.19.255254
21130.136.20.0/24130.136.20.1 to 130.136.20.254130.136.20.255254
22130.136.21.0/24130.136.21.1 to 130.136.21.254130.136.21.255254
23130.136.22.0/24130.136.22.1 to 130.136.22.254130.136.22.255254
24130.136.23.0/24130.136.23.1 to 130.136.23.254130.136.23.255254
25130.136.24.0/24130.136.24.1 to 130.136.24.254130.136.24.255254
26130.136.25.0/24130.136.25.1 to 130.136.25.254130.136.25.255254
27130.136.26.0/24130.136.26.1 to 130.136.26.254130.136.26.255254
28130.136.27.0/24130.136.27.1 to 130.136.27.254130.136.27.255254
29130.136.28.0/24130.136.28.1 to 130.136.28.254130.136.28.255254
30130.136.29.0/24130.136.29.1 to 130.136.29.254130.136.29.255254
31130.136.30.0/24130.136.30.1 to 130.136.30.254130.136.30.255254
32130.136.31.0/24130.136.31.1 to 130.136.31.254130.136.31.255254
33130.136.32.0/24130.136.32.1 to 130.136.32.254130.136.32.255254
34130.136.33.0/24130.136.33.1 to 130.136.33.254130.136.33.255254
35130.136.34.0/24130.136.34.1 to 130.136.34.254130.136.34.255254
36130.136.35.0/24130.136.35.1 to 130.136.35.254130.136.35.255254
37130.136.36.0/24130.136.36.1 to 130.136.36.254130.136.36.255254
38130.136.37.0/24130.136.37.1 to 130.136.37.254130.136.37.255254
39130.136.38.0/24130.136.38.1 to 130.136.38.254130.136.38.255254
40130.136.39.0/24130.136.39.1 to 130.136.39.254130.136.39.255254
41130.136.40.0/24130.136.40.1 to 130.136.40.254130.136.40.255254
42130.136.41.0/24130.136.41.1 to 130.136.41.254130.136.41.255254
43130.136.42.0/24130.136.42.1 to 130.136.42.254130.136.42.255254
44130.136.43.0/24130.136.43.1 to 130.136.43.254130.136.43.255254
45130.136.44.0/24130.136.44.1 to 130.136.44.254130.136.44.255254
46130.136.45.0/24130.136.45.1 to 130.136.45.254130.136.45.255254
47130.136.46.0/24130.136.46.1 to 130.136.46.254130.136.46.255254
48130.136.47.0/24130.136.47.1 to 130.136.47.254130.136.47.255254
49130.136.48.0/24130.136.48.1 to 130.136.48.254130.136.48.255254
50130.136.49.0/24130.136.49.1 to 130.136.49.254130.136.49.255254
51130.136.50.0/24130.136.50.1 to 130.136.50.254130.136.50.255254
52130.136.51.0/24130.136.51.1 to 130.136.51.254130.136.51.255254
53130.136.52.0/24130.136.52.1 to 130.136.52.254130.136.52.255254
54130.136.53.0/24130.136.53.1 to 130.136.53.254130.136.53.255254
55130.136.54.0/24130.136.54.1 to 130.136.54.254130.136.54.255254
56130.136.55.0/24130.136.55.1 to 130.136.55.254130.136.55.255254
57130.136.56.0/24130.136.56.1 to 130.136.56.254130.136.56.255254
58130.136.57.0/24130.136.57.1 to 130.136.57.254130.136.57.255254
59130.136.58.0/24130.136.58.1 to 130.136.58.254130.136.58.255254
60130.136.59.0/24130.136.59.1 to 130.136.59.254130.136.59.255254
61130.136.60.0/24130.136.60.1 to 130.136.60.254130.136.60.255254
62130.136.61.0/24130.136.61.1 to 130.136.61.254130.136.61.255254
63130.136.62.0/24130.136.62.1 to 130.136.62.254130.136.62.255254
64130.136.63.0/24130.136.63.1 to 130.136.63.254130.136.63.255254
65130.136.64.0/24130.136.64.1 to 130.136.64.254130.136.64.255254
66130.136.65.0/24130.136.65.1 to 130.136.65.254130.136.65.255254
67130.136.66.0/24130.136.66.1 to 130.136.66.254130.136.66.255254
68130.136.67.0/24130.136.67.1 to 130.136.67.254130.136.67.255254
69130.136.68.0/24130.136.68.1 to 130.136.68.254130.136.68.255254
70130.136.69.0/24130.136.69.1 to 130.136.69.254130.136.69.255254
71130.136.70.0/24130.136.70.1 to 130.136.70.254130.136.70.255254
72130.136.71.0/24130.136.71.1 to 130.136.71.254130.136.71.255254
73130.136.72.0/24130.136.72.1 to 130.136.72.254130.136.72.255254
74130.136.73.0/24130.136.73.1 to 130.136.73.254130.136.73.255254
75130.136.74.0/24130.136.74.1 to 130.136.74.254130.136.74.255254
76130.136.75.0/24130.136.75.1 to 130.136.75.254130.136.75.255254
77130.136.76.0/24130.136.76.1 to 130.136.76.254130.136.76.255254
78130.136.77.0/24130.136.77.1 to 130.136.77.254130.136.77.255254
79130.136.78.0/24130.136.78.1 to 130.136.78.254130.136.78.255254
80130.136.79.0/24130.136.79.1 to 130.136.79.254130.136.79.255254
81130.136.80.0/24130.136.80.1 to 130.136.80.254130.136.80.255254
82130.136.81.0/24130.136.81.1 to 130.136.81.254130.136.81.255254
83130.136.82.0/24130.136.82.1 to 130.136.82.254130.136.82.255254
84130.136.83.0/24130.136.83.1 to 130.136.83.254130.136.83.255254
85130.136.84.0/24130.136.84.1 to 130.136.84.254130.136.84.255254
86130.136.85.0/24130.136.85.1 to 130.136.85.254130.136.85.255254
87130.136.86.0/24130.136.86.1 to 130.136.86.254130.136.86.255254
88130.136.87.0/24130.136.87.1 to 130.136.87.254130.136.87.255254
89130.136.88.0/24130.136.88.1 to 130.136.88.254130.136.88.255254
90130.136.89.0/24130.136.89.1 to 130.136.89.254130.136.89.255254
91130.136.90.0/24130.136.90.1 to 130.136.90.254130.136.90.255254
92130.136.91.0/24130.136.91.1 to 130.136.91.254130.136.91.255254
93130.136.92.0/24130.136.92.1 to 130.136.92.254130.136.92.255254
94130.136.93.0/24130.136.93.1 to 130.136.93.254130.136.93.255254
95130.136.94.0/24130.136.94.1 to 130.136.94.254130.136.94.255254
96130.136.95.0/24130.136.95.1 to 130.136.95.254130.136.95.255254
97130.136.96.0/24130.136.96.1 to 130.136.96.254130.136.96.255254
98130.136.97.0/24130.136.97.1 to 130.136.97.254130.136.97.255254
99130.136.98.0/24130.136.98.1 to 130.136.98.254130.136.98.255254
100130.136.99.0/24130.136.99.1 to 130.136.99.254130.136.99.255254
101130.136.100.0/24130.136.100.1 to 130.136.100.254130.136.100.255254
102130.136.101.0/24130.136.101.1 to 130.136.101.254130.136.101.255254
103130.136.102.0/24130.136.102.1 to 130.136.102.254130.136.102.255254
104130.136.103.0/24130.136.103.1 to 130.136.103.254130.136.103.255254
105130.136.104.0/24130.136.104.1 to 130.136.104.254130.136.104.255254
106130.136.105.0/24130.136.105.1 to 130.136.105.254130.136.105.255254
107130.136.106.0/24130.136.106.1 to 130.136.106.254130.136.106.255254
108130.136.107.0/24130.136.107.1 to 130.136.107.254130.136.107.255254
109130.136.108.0/24130.136.108.1 to 130.136.108.254130.136.108.255254
110130.136.109.0/24130.136.109.1 to 130.136.109.254130.136.109.255254
111130.136.110.0/24130.136.110.1 to 130.136.110.254130.136.110.255254
112130.136.111.0/24130.136.111.1 to 130.136.111.254130.136.111.255254
113130.136.112.0/24130.136.112.1 to 130.136.112.254130.136.112.255254
114130.136.113.0/24130.136.113.1 to 130.136.113.254130.136.113.255254
115130.136.114.0/24130.136.114.1 to 130.136.114.254130.136.114.255254
116130.136.115.0/24130.136.115.1 to 130.136.115.254130.136.115.255254
117130.136.116.0/24130.136.116.1 to 130.136.116.254130.136.116.255254
118130.136.117.0/24130.136.117.1 to 130.136.117.254130.136.117.255254
119130.136.118.0/24130.136.118.1 to 130.136.118.254130.136.118.255254
120130.136.119.0/24130.136.119.1 to 130.136.119.254130.136.119.255254
121130.136.120.0/24130.136.120.1 to 130.136.120.254130.136.120.255254
122130.136.121.0/24130.136.121.1 to 130.136.121.254130.136.121.255254
123130.136.122.0/24130.136.122.1 to 130.136.122.254130.136.122.255254
124130.136.123.0/24130.136.123.1 to 130.136.123.254130.136.123.255254
125130.136.124.0/24130.136.124.1 to 130.136.124.254130.136.124.255254
126130.136.125.0/24130.136.125.1 to 130.136.125.254130.136.125.255254
127130.136.126.0/24130.136.126.1 to 130.136.126.254130.136.126.255254
128130.136.127.0/24130.136.127.1 to 130.136.127.254130.136.127.255254
129130.136.128.0/24130.136.128.1 to 130.136.128.254130.136.128.255254
130130.136.129.0/24130.136.129.1 to 130.136.129.254130.136.129.255254
131130.136.130.0/24130.136.130.1 to 130.136.130.254130.136.130.255254
132130.136.131.0/24130.136.131.1 to 130.136.131.254130.136.131.255254
133130.136.132.0/24130.136.132.1 to 130.136.132.254130.136.132.255254
134130.136.133.0/24130.136.133.1 to 130.136.133.254130.136.133.255254
135130.136.134.0/24130.136.134.1 to 130.136.134.254130.136.134.255254
136130.136.135.0/24130.136.135.1 to 130.136.135.254130.136.135.255254
137130.136.136.0/24130.136.136.1 to 130.136.136.254130.136.136.255254
138130.136.137.0/24130.136.137.1 to 130.136.137.254130.136.137.255254
139130.136.138.0/24130.136.138.1 to 130.136.138.254130.136.138.255254
140130.136.139.0/24130.136.139.1 to 130.136.139.254130.136.139.255254
141130.136.140.0/24130.136.140.1 to 130.136.140.254130.136.140.255254
142130.136.141.0/24130.136.141.1 to 130.136.141.254130.136.141.255254
143130.136.142.0/24130.136.142.1 to 130.136.142.254130.136.142.255254
144130.136.143.0/24130.136.143.1 to 130.136.143.254130.136.143.255254
145130.136.144.0/24130.136.144.1 to 130.136.144.254130.136.144.255254
146130.136.145.0/24130.136.145.1 to 130.136.145.254130.136.145.255254
147130.136.146.0/24130.136.146.1 to 130.136.146.254130.136.146.255254
148130.136.147.0/24130.136.147.1 to 130.136.147.254130.136.147.255254
149130.136.148.0/24130.136.148.1 to 130.136.148.254130.136.148.255254
150130.136.149.0/24130.136.149.1 to 130.136.149.254130.136.149.255254
151130.136.150.0/24130.136.150.1 to 130.136.150.254130.136.150.255254
152130.136.151.0/24130.136.151.1 to 130.136.151.254130.136.151.255254
153130.136.152.0/24130.136.152.1 to 130.136.152.254130.136.152.255254
154130.136.153.0/24130.136.153.1 to 130.136.153.254130.136.153.255254
155130.136.154.0/24130.136.154.1 to 130.136.154.254130.136.154.255254
156130.136.155.0/24130.136.155.1 to 130.136.155.254130.136.155.255254
157130.136.156.0/24130.136.156.1 to 130.136.156.254130.136.156.255254
158130.136.157.0/24130.136.157.1 to 130.136.157.254130.136.157.255254
159130.136.158.0/24130.136.158.1 to 130.136.158.254130.136.158.255254
160130.136.159.0/24130.136.159.1 to 130.136.159.254130.136.159.255254
161130.136.160.0/24130.136.160.1 to 130.136.160.254130.136.160.255254
162130.136.161.0/24130.136.161.1 to 130.136.161.254130.136.161.255254
163130.136.162.0/24130.136.162.1 to 130.136.162.254130.136.162.255254
164130.136.163.0/24130.136.163.1 to 130.136.163.254130.136.163.255254
165130.136.164.0/24130.136.164.1 to 130.136.164.254130.136.164.255254
166130.136.165.0/24130.136.165.1 to 130.136.165.254130.136.165.255254
167130.136.166.0/24130.136.166.1 to 130.136.166.254130.136.166.255254
168130.136.167.0/24130.136.167.1 to 130.136.167.254130.136.167.255254
169130.136.168.0/24130.136.168.1 to 130.136.168.254130.136.168.255254
170130.136.169.0/24130.136.169.1 to 130.136.169.254130.136.169.255254
171130.136.170.0/24130.136.170.1 to 130.136.170.254130.136.170.255254
172130.136.171.0/24130.136.171.1 to 130.136.171.254130.136.171.255254
173130.136.172.0/24130.136.172.1 to 130.136.172.254130.136.172.255254
174130.136.173.0/24130.136.173.1 to 130.136.173.254130.136.173.255254
175130.136.174.0/24130.136.174.1 to 130.136.174.254130.136.174.255254
176130.136.175.0/24130.136.175.1 to 130.136.175.254130.136.175.255254
177130.136.176.0/24130.136.176.1 to 130.136.176.254130.136.176.255254
178130.136.177.0/24130.136.177.1 to 130.136.177.254130.136.177.255254
179130.136.178.0/24130.136.178.1 to 130.136.178.254130.136.178.255254
180130.136.179.0/24130.136.179.1 to 130.136.179.254130.136.179.255254
181130.136.180.0/24130.136.180.1 to 130.136.180.254130.136.180.255254
182130.136.181.0/24130.136.181.1 to 130.136.181.254130.136.181.255254
183130.136.182.0/24130.136.182.1 to 130.136.182.254130.136.182.255254
184130.136.183.0/24130.136.183.1 to 130.136.183.254130.136.183.255254
185130.136.184.0/24130.136.184.1 to 130.136.184.254130.136.184.255254
186130.136.185.0/24130.136.185.1 to 130.136.185.254130.136.185.255254
187130.136.186.0/24130.136.186.1 to 130.136.186.254130.136.186.255254
188130.136.187.0/24130.136.187.1 to 130.136.187.254130.136.187.255254
189130.136.188.0/24130.136.188.1 to 130.136.188.254130.136.188.255254
190130.136.189.0/24130.136.189.1 to 130.136.189.254130.136.189.255254
191130.136.190.0/24130.136.190.1 to 130.136.190.254130.136.190.255254
192130.136.191.0/24130.136.191.1 to 130.136.191.254130.136.191.255254
193130.136.192.0/24130.136.192.1 to 130.136.192.254130.136.192.255254
194130.136.193.0/24130.136.193.1 to 130.136.193.254130.136.193.255254
195130.136.194.0/24130.136.194.1 to 130.136.194.254130.136.194.255254
196130.136.195.0/24130.136.195.1 to 130.136.195.254130.136.195.255254
197130.136.196.0/24130.136.196.1 to 130.136.196.254130.136.196.255254
198130.136.197.0/24130.136.197.1 to 130.136.197.254130.136.197.255254
199130.136.198.0/24130.136.198.1 to 130.136.198.254130.136.198.255254
200130.136.199.0/24130.136.199.1 to 130.136.199.254130.136.199.255254
201130.136.200.0/24130.136.200.1 to 130.136.200.254130.136.200.255254
202130.136.201.0/24130.136.201.1 to 130.136.201.254130.136.201.255254
203130.136.202.0/24130.136.202.1 to 130.136.202.254130.136.202.255254
204130.136.203.0/24130.136.203.1 to 130.136.203.254130.136.203.255254
205130.136.204.0/24130.136.204.1 to 130.136.204.254130.136.204.255254
206130.136.205.0/24130.136.205.1 to 130.136.205.254130.136.205.255254
207130.136.206.0/24130.136.206.1 to 130.136.206.254130.136.206.255254
208130.136.207.0/24130.136.207.1 to 130.136.207.254130.136.207.255254
209130.136.208.0/24130.136.208.1 to 130.136.208.254130.136.208.255254
210130.136.209.0/24130.136.209.1 to 130.136.209.254130.136.209.255254
211130.136.210.0/24130.136.210.1 to 130.136.210.254130.136.210.255254
212130.136.211.0/24130.136.211.1 to 130.136.211.254130.136.211.255254
213130.136.212.0/24130.136.212.1 to 130.136.212.254130.136.212.255254
214130.136.213.0/24130.136.213.1 to 130.136.213.254130.136.213.255254
215130.136.214.0/24130.136.214.1 to 130.136.214.254130.136.214.255254
216130.136.215.0/24130.136.215.1 to 130.136.215.254130.136.215.255254
217130.136.216.0/24130.136.216.1 to 130.136.216.254130.136.216.255254
218130.136.217.0/24130.136.217.1 to 130.136.217.254130.136.217.255254
219130.136.218.0/24130.136.218.1 to 130.136.218.254130.136.218.255254
220130.136.219.0/24130.136.219.1 to 130.136.219.254130.136.219.255254
221130.136.220.0/24130.136.220.1 to 130.136.220.254130.136.220.255254
222130.136.221.0/24130.136.221.1 to 130.136.221.254130.136.221.255254
223130.136.222.0/24130.136.222.1 to 130.136.222.254130.136.222.255254
224130.136.223.0/24130.136.223.1 to 130.136.223.254130.136.223.255254
225130.136.224.0/24130.136.224.1 to 130.136.224.254130.136.224.255254
226130.136.225.0/24130.136.225.1 to 130.136.225.254130.136.225.255254
227130.136.226.0/24130.136.226.1 to 130.136.226.254130.136.226.255254
228130.136.227.0/24130.136.227.1 to 130.136.227.254130.136.227.255254
229130.136.228.0/24130.136.228.1 to 130.136.228.254130.136.228.255254
230130.136.229.0/24130.136.229.1 to 130.136.229.254130.136.229.255254
231130.136.230.0/24130.136.230.1 to 130.136.230.254130.136.230.255254
232130.136.231.0/24130.136.231.1 to 130.136.231.254130.136.231.255254
233130.136.232.0/24130.136.232.1 to 130.136.232.254130.136.232.255254
234130.136.233.0/24130.136.233.1 to 130.136.233.254130.136.233.255254
235130.136.234.0/24130.136.234.1 to 130.136.234.254130.136.234.255254
236130.136.235.0/24130.136.235.1 to 130.136.235.254130.136.235.255254
237130.136.236.0/24130.136.236.1 to 130.136.236.254130.136.236.255254
238130.136.237.0/24130.136.237.1 to 130.136.237.254130.136.237.255254
239130.136.238.0/24130.136.238.1 to 130.136.238.254130.136.238.255254
240130.136.239.0/24130.136.239.1 to 130.136.239.254130.136.239.255254
241130.136.240.0/24130.136.240.1 to 130.136.240.254130.136.240.255254
242130.136.241.0/24130.136.241.1 to 130.136.241.254130.136.241.255254
243130.136.242.0/24130.136.242.1 to 130.136.242.254130.136.242.255254
244130.136.243.0/24130.136.243.1 to 130.136.243.254130.136.243.255254
245130.136.244.0/24130.136.244.1 to 130.136.244.254130.136.244.255254
246130.136.245.0/24130.136.245.1 to 130.136.245.254130.136.245.255254
247130.136.246.0/24130.136.246.1 to 130.136.246.254130.136.246.255254
248130.136.247.0/24130.136.247.1 to 130.136.247.254130.136.247.255254
249130.136.248.0/24130.136.248.1 to 130.136.248.254130.136.248.255254
250130.136.249.0/24130.136.249.1 to 130.136.249.254130.136.249.255254
251130.136.250.0/24130.136.250.1 to 130.136.250.254130.136.250.255254
252130.136.251.0/24130.136.251.1 to 130.136.251.254130.136.251.255254
253130.136.252.0/24130.136.252.1 to 130.136.252.254130.136.252.255254
254130.136.253.0/24130.136.253.1 to 130.136.253.254130.136.253.255254
255130.136.254.0/24130.136.254.1 to 130.136.254.254130.136.254.255254
256130.136.255.0/24130.136.255.1 to 130.136.255.254130.136.255.255254

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.