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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.

Network182.136.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
182.136.0.0
Broadcast address
182.143.255.255
First usable
182.136.0.1
Last usable
182.143.255.254
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 B6880000 · Integer 3062366208 to 3062890495
Reverse DNS zones
136.182.in-addr.arpa
137.182.in-addr.arpa
138.182.in-addr.arpa
139.182.in-addr.arpa
140.182.in-addr.arpa
141.182.in-addr.arpa
142.182.in-addr.arpa
143.182.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
Address10110110.10001000.00000000.00000000182.136.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network10110110.10001000.00000000.00000000182.136.0.0
Broadcast10110110.10001111.11111111.11111111182.143.255.255
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)

182.136.0.0/13 makes 2,048 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1182.136.0.0/24182.136.0.1 to 182.136.0.254182.136.0.255254
2182.136.1.0/24182.136.1.1 to 182.136.1.254182.136.1.255254
3182.136.2.0/24182.136.2.1 to 182.136.2.254182.136.2.255254
4182.136.3.0/24182.136.3.1 to 182.136.3.254182.136.3.255254
5182.136.4.0/24182.136.4.1 to 182.136.4.254182.136.4.255254
6182.136.5.0/24182.136.5.1 to 182.136.5.254182.136.5.255254
7182.136.6.0/24182.136.6.1 to 182.136.6.254182.136.6.255254
8182.136.7.0/24182.136.7.1 to 182.136.7.254182.136.7.255254
9182.136.8.0/24182.136.8.1 to 182.136.8.254182.136.8.255254
10182.136.9.0/24182.136.9.1 to 182.136.9.254182.136.9.255254
11182.136.10.0/24182.136.10.1 to 182.136.10.254182.136.10.255254
12182.136.11.0/24182.136.11.1 to 182.136.11.254182.136.11.255254
13182.136.12.0/24182.136.12.1 to 182.136.12.254182.136.12.255254
14182.136.13.0/24182.136.13.1 to 182.136.13.254182.136.13.255254
15182.136.14.0/24182.136.14.1 to 182.136.14.254182.136.14.255254
16182.136.15.0/24182.136.15.1 to 182.136.15.254182.136.15.255254
17182.136.16.0/24182.136.16.1 to 182.136.16.254182.136.16.255254
18182.136.17.0/24182.136.17.1 to 182.136.17.254182.136.17.255254
19182.136.18.0/24182.136.18.1 to 182.136.18.254182.136.18.255254
20182.136.19.0/24182.136.19.1 to 182.136.19.254182.136.19.255254
21182.136.20.0/24182.136.20.1 to 182.136.20.254182.136.20.255254
22182.136.21.0/24182.136.21.1 to 182.136.21.254182.136.21.255254
23182.136.22.0/24182.136.22.1 to 182.136.22.254182.136.22.255254
24182.136.23.0/24182.136.23.1 to 182.136.23.254182.136.23.255254
25182.136.24.0/24182.136.24.1 to 182.136.24.254182.136.24.255254
26182.136.25.0/24182.136.25.1 to 182.136.25.254182.136.25.255254
27182.136.26.0/24182.136.26.1 to 182.136.26.254182.136.26.255254
28182.136.27.0/24182.136.27.1 to 182.136.27.254182.136.27.255254
29182.136.28.0/24182.136.28.1 to 182.136.28.254182.136.28.255254
30182.136.29.0/24182.136.29.1 to 182.136.29.254182.136.29.255254
31182.136.30.0/24182.136.30.1 to 182.136.30.254182.136.30.255254
32182.136.31.0/24182.136.31.1 to 182.136.31.254182.136.31.255254
33182.136.32.0/24182.136.32.1 to 182.136.32.254182.136.32.255254
34182.136.33.0/24182.136.33.1 to 182.136.33.254182.136.33.255254
35182.136.34.0/24182.136.34.1 to 182.136.34.254182.136.34.255254
36182.136.35.0/24182.136.35.1 to 182.136.35.254182.136.35.255254
37182.136.36.0/24182.136.36.1 to 182.136.36.254182.136.36.255254
38182.136.37.0/24182.136.37.1 to 182.136.37.254182.136.37.255254
39182.136.38.0/24182.136.38.1 to 182.136.38.254182.136.38.255254
40182.136.39.0/24182.136.39.1 to 182.136.39.254182.136.39.255254
41182.136.40.0/24182.136.40.1 to 182.136.40.254182.136.40.255254
42182.136.41.0/24182.136.41.1 to 182.136.41.254182.136.41.255254
43182.136.42.0/24182.136.42.1 to 182.136.42.254182.136.42.255254
44182.136.43.0/24182.136.43.1 to 182.136.43.254182.136.43.255254
45182.136.44.0/24182.136.44.1 to 182.136.44.254182.136.44.255254
46182.136.45.0/24182.136.45.1 to 182.136.45.254182.136.45.255254
47182.136.46.0/24182.136.46.1 to 182.136.46.254182.136.46.255254
48182.136.47.0/24182.136.47.1 to 182.136.47.254182.136.47.255254
49182.136.48.0/24182.136.48.1 to 182.136.48.254182.136.48.255254
50182.136.49.0/24182.136.49.1 to 182.136.49.254182.136.49.255254
51182.136.50.0/24182.136.50.1 to 182.136.50.254182.136.50.255254
52182.136.51.0/24182.136.51.1 to 182.136.51.254182.136.51.255254
53182.136.52.0/24182.136.52.1 to 182.136.52.254182.136.52.255254
54182.136.53.0/24182.136.53.1 to 182.136.53.254182.136.53.255254
55182.136.54.0/24182.136.54.1 to 182.136.54.254182.136.54.255254
56182.136.55.0/24182.136.55.1 to 182.136.55.254182.136.55.255254
57182.136.56.0/24182.136.56.1 to 182.136.56.254182.136.56.255254
58182.136.57.0/24182.136.57.1 to 182.136.57.254182.136.57.255254
59182.136.58.0/24182.136.58.1 to 182.136.58.254182.136.58.255254
60182.136.59.0/24182.136.59.1 to 182.136.59.254182.136.59.255254
61182.136.60.0/24182.136.60.1 to 182.136.60.254182.136.60.255254
62182.136.61.0/24182.136.61.1 to 182.136.61.254182.136.61.255254
63182.136.62.0/24182.136.62.1 to 182.136.62.254182.136.62.255254
64182.136.63.0/24182.136.63.1 to 182.136.63.254182.136.63.255254
65182.136.64.0/24182.136.64.1 to 182.136.64.254182.136.64.255254
66182.136.65.0/24182.136.65.1 to 182.136.65.254182.136.65.255254
67182.136.66.0/24182.136.66.1 to 182.136.66.254182.136.66.255254
68182.136.67.0/24182.136.67.1 to 182.136.67.254182.136.67.255254
69182.136.68.0/24182.136.68.1 to 182.136.68.254182.136.68.255254
70182.136.69.0/24182.136.69.1 to 182.136.69.254182.136.69.255254
71182.136.70.0/24182.136.70.1 to 182.136.70.254182.136.70.255254
72182.136.71.0/24182.136.71.1 to 182.136.71.254182.136.71.255254
73182.136.72.0/24182.136.72.1 to 182.136.72.254182.136.72.255254
74182.136.73.0/24182.136.73.1 to 182.136.73.254182.136.73.255254
75182.136.74.0/24182.136.74.1 to 182.136.74.254182.136.74.255254
76182.136.75.0/24182.136.75.1 to 182.136.75.254182.136.75.255254
77182.136.76.0/24182.136.76.1 to 182.136.76.254182.136.76.255254
78182.136.77.0/24182.136.77.1 to 182.136.77.254182.136.77.255254
79182.136.78.0/24182.136.78.1 to 182.136.78.254182.136.78.255254
80182.136.79.0/24182.136.79.1 to 182.136.79.254182.136.79.255254
81182.136.80.0/24182.136.80.1 to 182.136.80.254182.136.80.255254
82182.136.81.0/24182.136.81.1 to 182.136.81.254182.136.81.255254
83182.136.82.0/24182.136.82.1 to 182.136.82.254182.136.82.255254
84182.136.83.0/24182.136.83.1 to 182.136.83.254182.136.83.255254
85182.136.84.0/24182.136.84.1 to 182.136.84.254182.136.84.255254
86182.136.85.0/24182.136.85.1 to 182.136.85.254182.136.85.255254
87182.136.86.0/24182.136.86.1 to 182.136.86.254182.136.86.255254
88182.136.87.0/24182.136.87.1 to 182.136.87.254182.136.87.255254
89182.136.88.0/24182.136.88.1 to 182.136.88.254182.136.88.255254
90182.136.89.0/24182.136.89.1 to 182.136.89.254182.136.89.255254
91182.136.90.0/24182.136.90.1 to 182.136.90.254182.136.90.255254
92182.136.91.0/24182.136.91.1 to 182.136.91.254182.136.91.255254
93182.136.92.0/24182.136.92.1 to 182.136.92.254182.136.92.255254
94182.136.93.0/24182.136.93.1 to 182.136.93.254182.136.93.255254
95182.136.94.0/24182.136.94.1 to 182.136.94.254182.136.94.255254
96182.136.95.0/24182.136.95.1 to 182.136.95.254182.136.95.255254
97182.136.96.0/24182.136.96.1 to 182.136.96.254182.136.96.255254
98182.136.97.0/24182.136.97.1 to 182.136.97.254182.136.97.255254
99182.136.98.0/24182.136.98.1 to 182.136.98.254182.136.98.255254
100182.136.99.0/24182.136.99.1 to 182.136.99.254182.136.99.255254
101182.136.100.0/24182.136.100.1 to 182.136.100.254182.136.100.255254
102182.136.101.0/24182.136.101.1 to 182.136.101.254182.136.101.255254
103182.136.102.0/24182.136.102.1 to 182.136.102.254182.136.102.255254
104182.136.103.0/24182.136.103.1 to 182.136.103.254182.136.103.255254
105182.136.104.0/24182.136.104.1 to 182.136.104.254182.136.104.255254
106182.136.105.0/24182.136.105.1 to 182.136.105.254182.136.105.255254
107182.136.106.0/24182.136.106.1 to 182.136.106.254182.136.106.255254
108182.136.107.0/24182.136.107.1 to 182.136.107.254182.136.107.255254
109182.136.108.0/24182.136.108.1 to 182.136.108.254182.136.108.255254
110182.136.109.0/24182.136.109.1 to 182.136.109.254182.136.109.255254
111182.136.110.0/24182.136.110.1 to 182.136.110.254182.136.110.255254
112182.136.111.0/24182.136.111.1 to 182.136.111.254182.136.111.255254
113182.136.112.0/24182.136.112.1 to 182.136.112.254182.136.112.255254
114182.136.113.0/24182.136.113.1 to 182.136.113.254182.136.113.255254
115182.136.114.0/24182.136.114.1 to 182.136.114.254182.136.114.255254
116182.136.115.0/24182.136.115.1 to 182.136.115.254182.136.115.255254
117182.136.116.0/24182.136.116.1 to 182.136.116.254182.136.116.255254
118182.136.117.0/24182.136.117.1 to 182.136.117.254182.136.117.255254
119182.136.118.0/24182.136.118.1 to 182.136.118.254182.136.118.255254
120182.136.119.0/24182.136.119.1 to 182.136.119.254182.136.119.255254
121182.136.120.0/24182.136.120.1 to 182.136.120.254182.136.120.255254
122182.136.121.0/24182.136.121.1 to 182.136.121.254182.136.121.255254
123182.136.122.0/24182.136.122.1 to 182.136.122.254182.136.122.255254
124182.136.123.0/24182.136.123.1 to 182.136.123.254182.136.123.255254
125182.136.124.0/24182.136.124.1 to 182.136.124.254182.136.124.255254
126182.136.125.0/24182.136.125.1 to 182.136.125.254182.136.125.255254
127182.136.126.0/24182.136.126.1 to 182.136.126.254182.136.126.255254
128182.136.127.0/24182.136.127.1 to 182.136.127.254182.136.127.255254
129182.136.128.0/24182.136.128.1 to 182.136.128.254182.136.128.255254
130182.136.129.0/24182.136.129.1 to 182.136.129.254182.136.129.255254
131182.136.130.0/24182.136.130.1 to 182.136.130.254182.136.130.255254
132182.136.131.0/24182.136.131.1 to 182.136.131.254182.136.131.255254
133182.136.132.0/24182.136.132.1 to 182.136.132.254182.136.132.255254
134182.136.133.0/24182.136.133.1 to 182.136.133.254182.136.133.255254
135182.136.134.0/24182.136.134.1 to 182.136.134.254182.136.134.255254
136182.136.135.0/24182.136.135.1 to 182.136.135.254182.136.135.255254
137182.136.136.0/24182.136.136.1 to 182.136.136.254182.136.136.255254
138182.136.137.0/24182.136.137.1 to 182.136.137.254182.136.137.255254
139182.136.138.0/24182.136.138.1 to 182.136.138.254182.136.138.255254
140182.136.139.0/24182.136.139.1 to 182.136.139.254182.136.139.255254
141182.136.140.0/24182.136.140.1 to 182.136.140.254182.136.140.255254
142182.136.141.0/24182.136.141.1 to 182.136.141.254182.136.141.255254
143182.136.142.0/24182.136.142.1 to 182.136.142.254182.136.142.255254
144182.136.143.0/24182.136.143.1 to 182.136.143.254182.136.143.255254
145182.136.144.0/24182.136.144.1 to 182.136.144.254182.136.144.255254
146182.136.145.0/24182.136.145.1 to 182.136.145.254182.136.145.255254
147182.136.146.0/24182.136.146.1 to 182.136.146.254182.136.146.255254
148182.136.147.0/24182.136.147.1 to 182.136.147.254182.136.147.255254
149182.136.148.0/24182.136.148.1 to 182.136.148.254182.136.148.255254
150182.136.149.0/24182.136.149.1 to 182.136.149.254182.136.149.255254
151182.136.150.0/24182.136.150.1 to 182.136.150.254182.136.150.255254
152182.136.151.0/24182.136.151.1 to 182.136.151.254182.136.151.255254
153182.136.152.0/24182.136.152.1 to 182.136.152.254182.136.152.255254
154182.136.153.0/24182.136.153.1 to 182.136.153.254182.136.153.255254
155182.136.154.0/24182.136.154.1 to 182.136.154.254182.136.154.255254
156182.136.155.0/24182.136.155.1 to 182.136.155.254182.136.155.255254
157182.136.156.0/24182.136.156.1 to 182.136.156.254182.136.156.255254
158182.136.157.0/24182.136.157.1 to 182.136.157.254182.136.157.255254
159182.136.158.0/24182.136.158.1 to 182.136.158.254182.136.158.255254
160182.136.159.0/24182.136.159.1 to 182.136.159.254182.136.159.255254
161182.136.160.0/24182.136.160.1 to 182.136.160.254182.136.160.255254
162182.136.161.0/24182.136.161.1 to 182.136.161.254182.136.161.255254
163182.136.162.0/24182.136.162.1 to 182.136.162.254182.136.162.255254
164182.136.163.0/24182.136.163.1 to 182.136.163.254182.136.163.255254
165182.136.164.0/24182.136.164.1 to 182.136.164.254182.136.164.255254
166182.136.165.0/24182.136.165.1 to 182.136.165.254182.136.165.255254
167182.136.166.0/24182.136.166.1 to 182.136.166.254182.136.166.255254
168182.136.167.0/24182.136.167.1 to 182.136.167.254182.136.167.255254
169182.136.168.0/24182.136.168.1 to 182.136.168.254182.136.168.255254
170182.136.169.0/24182.136.169.1 to 182.136.169.254182.136.169.255254
171182.136.170.0/24182.136.170.1 to 182.136.170.254182.136.170.255254
172182.136.171.0/24182.136.171.1 to 182.136.171.254182.136.171.255254
173182.136.172.0/24182.136.172.1 to 182.136.172.254182.136.172.255254
174182.136.173.0/24182.136.173.1 to 182.136.173.254182.136.173.255254
175182.136.174.0/24182.136.174.1 to 182.136.174.254182.136.174.255254
176182.136.175.0/24182.136.175.1 to 182.136.175.254182.136.175.255254
177182.136.176.0/24182.136.176.1 to 182.136.176.254182.136.176.255254
178182.136.177.0/24182.136.177.1 to 182.136.177.254182.136.177.255254
179182.136.178.0/24182.136.178.1 to 182.136.178.254182.136.178.255254
180182.136.179.0/24182.136.179.1 to 182.136.179.254182.136.179.255254
181182.136.180.0/24182.136.180.1 to 182.136.180.254182.136.180.255254
182182.136.181.0/24182.136.181.1 to 182.136.181.254182.136.181.255254
183182.136.182.0/24182.136.182.1 to 182.136.182.254182.136.182.255254
184182.136.183.0/24182.136.183.1 to 182.136.183.254182.136.183.255254
185182.136.184.0/24182.136.184.1 to 182.136.184.254182.136.184.255254
186182.136.185.0/24182.136.185.1 to 182.136.185.254182.136.185.255254
187182.136.186.0/24182.136.186.1 to 182.136.186.254182.136.186.255254
188182.136.187.0/24182.136.187.1 to 182.136.187.254182.136.187.255254
189182.136.188.0/24182.136.188.1 to 182.136.188.254182.136.188.255254
190182.136.189.0/24182.136.189.1 to 182.136.189.254182.136.189.255254
191182.136.190.0/24182.136.190.1 to 182.136.190.254182.136.190.255254
192182.136.191.0/24182.136.191.1 to 182.136.191.254182.136.191.255254
193182.136.192.0/24182.136.192.1 to 182.136.192.254182.136.192.255254
194182.136.193.0/24182.136.193.1 to 182.136.193.254182.136.193.255254
195182.136.194.0/24182.136.194.1 to 182.136.194.254182.136.194.255254
196182.136.195.0/24182.136.195.1 to 182.136.195.254182.136.195.255254
197182.136.196.0/24182.136.196.1 to 182.136.196.254182.136.196.255254
198182.136.197.0/24182.136.197.1 to 182.136.197.254182.136.197.255254
199182.136.198.0/24182.136.198.1 to 182.136.198.254182.136.198.255254
200182.136.199.0/24182.136.199.1 to 182.136.199.254182.136.199.255254
201182.136.200.0/24182.136.200.1 to 182.136.200.254182.136.200.255254
202182.136.201.0/24182.136.201.1 to 182.136.201.254182.136.201.255254
203182.136.202.0/24182.136.202.1 to 182.136.202.254182.136.202.255254
204182.136.203.0/24182.136.203.1 to 182.136.203.254182.136.203.255254
205182.136.204.0/24182.136.204.1 to 182.136.204.254182.136.204.255254
206182.136.205.0/24182.136.205.1 to 182.136.205.254182.136.205.255254
207182.136.206.0/24182.136.206.1 to 182.136.206.254182.136.206.255254
208182.136.207.0/24182.136.207.1 to 182.136.207.254182.136.207.255254
209182.136.208.0/24182.136.208.1 to 182.136.208.254182.136.208.255254
210182.136.209.0/24182.136.209.1 to 182.136.209.254182.136.209.255254
211182.136.210.0/24182.136.210.1 to 182.136.210.254182.136.210.255254
212182.136.211.0/24182.136.211.1 to 182.136.211.254182.136.211.255254
213182.136.212.0/24182.136.212.1 to 182.136.212.254182.136.212.255254
214182.136.213.0/24182.136.213.1 to 182.136.213.254182.136.213.255254
215182.136.214.0/24182.136.214.1 to 182.136.214.254182.136.214.255254
216182.136.215.0/24182.136.215.1 to 182.136.215.254182.136.215.255254
217182.136.216.0/24182.136.216.1 to 182.136.216.254182.136.216.255254
218182.136.217.0/24182.136.217.1 to 182.136.217.254182.136.217.255254
219182.136.218.0/24182.136.218.1 to 182.136.218.254182.136.218.255254
220182.136.219.0/24182.136.219.1 to 182.136.219.254182.136.219.255254
221182.136.220.0/24182.136.220.1 to 182.136.220.254182.136.220.255254
222182.136.221.0/24182.136.221.1 to 182.136.221.254182.136.221.255254
223182.136.222.0/24182.136.222.1 to 182.136.222.254182.136.222.255254
224182.136.223.0/24182.136.223.1 to 182.136.223.254182.136.223.255254
225182.136.224.0/24182.136.224.1 to 182.136.224.254182.136.224.255254
226182.136.225.0/24182.136.225.1 to 182.136.225.254182.136.225.255254
227182.136.226.0/24182.136.226.1 to 182.136.226.254182.136.226.255254
228182.136.227.0/24182.136.227.1 to 182.136.227.254182.136.227.255254
229182.136.228.0/24182.136.228.1 to 182.136.228.254182.136.228.255254
230182.136.229.0/24182.136.229.1 to 182.136.229.254182.136.229.255254
231182.136.230.0/24182.136.230.1 to 182.136.230.254182.136.230.255254
232182.136.231.0/24182.136.231.1 to 182.136.231.254182.136.231.255254
233182.136.232.0/24182.136.232.1 to 182.136.232.254182.136.232.255254
234182.136.233.0/24182.136.233.1 to 182.136.233.254182.136.233.255254
235182.136.234.0/24182.136.234.1 to 182.136.234.254182.136.234.255254
236182.136.235.0/24182.136.235.1 to 182.136.235.254182.136.235.255254
237182.136.236.0/24182.136.236.1 to 182.136.236.254182.136.236.255254
238182.136.237.0/24182.136.237.1 to 182.136.237.254182.136.237.255254
239182.136.238.0/24182.136.238.1 to 182.136.238.254182.136.238.255254
240182.136.239.0/24182.136.239.1 to 182.136.239.254182.136.239.255254
241182.136.240.0/24182.136.240.1 to 182.136.240.254182.136.240.255254
242182.136.241.0/24182.136.241.1 to 182.136.241.254182.136.241.255254
243182.136.242.0/24182.136.242.1 to 182.136.242.254182.136.242.255254
244182.136.243.0/24182.136.243.1 to 182.136.243.254182.136.243.255254
245182.136.244.0/24182.136.244.1 to 182.136.244.254182.136.244.255254
246182.136.245.0/24182.136.245.1 to 182.136.245.254182.136.245.255254
247182.136.246.0/24182.136.246.1 to 182.136.246.254182.136.246.255254
248182.136.247.0/24182.136.247.1 to 182.136.247.254182.136.247.255254
249182.136.248.0/24182.136.248.1 to 182.136.248.254182.136.248.255254
250182.136.249.0/24182.136.249.1 to 182.136.249.254182.136.249.255254
251182.136.250.0/24182.136.250.1 to 182.136.250.254182.136.250.255254
252182.136.251.0/24182.136.251.1 to 182.136.251.254182.136.251.255254
253182.136.252.0/24182.136.252.1 to 182.136.252.254182.136.252.255254
254182.136.253.0/24182.136.253.1 to 182.136.253.254182.136.253.255254
255182.136.254.0/24182.136.254.1 to 182.136.254.254182.136.254.255254
256182.136.255.0/24182.136.255.1 to 182.136.255.254182.136.255.255254

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.