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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.

Network137.76.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
137.76.0.0
Broadcast address
137.79.255.255
First usable
137.76.0.1
Last usable
137.79.255.254
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 894C0000 · Integer 2303459328 to 2303721471
Reverse DNS zones
76.137.in-addr.arpa
77.137.in-addr.arpa
78.137.in-addr.arpa
79.137.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
Address10001001.01001100.00000000.00000000137.76.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10001001.01001100.00000000.00000000137.76.0.0
Broadcast10001001.01001111.11111111.11111111137.79.255.255
Split into smaller subnets/24
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

137.76.0.0/14 makes 1,024 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1137.76.0.0/24137.76.0.1 to 137.76.0.254137.76.0.255254
2137.76.1.0/24137.76.1.1 to 137.76.1.254137.76.1.255254
3137.76.2.0/24137.76.2.1 to 137.76.2.254137.76.2.255254
4137.76.3.0/24137.76.3.1 to 137.76.3.254137.76.3.255254
5137.76.4.0/24137.76.4.1 to 137.76.4.254137.76.4.255254
6137.76.5.0/24137.76.5.1 to 137.76.5.254137.76.5.255254
7137.76.6.0/24137.76.6.1 to 137.76.6.254137.76.6.255254
8137.76.7.0/24137.76.7.1 to 137.76.7.254137.76.7.255254
9137.76.8.0/24137.76.8.1 to 137.76.8.254137.76.8.255254
10137.76.9.0/24137.76.9.1 to 137.76.9.254137.76.9.255254
11137.76.10.0/24137.76.10.1 to 137.76.10.254137.76.10.255254
12137.76.11.0/24137.76.11.1 to 137.76.11.254137.76.11.255254
13137.76.12.0/24137.76.12.1 to 137.76.12.254137.76.12.255254
14137.76.13.0/24137.76.13.1 to 137.76.13.254137.76.13.255254
15137.76.14.0/24137.76.14.1 to 137.76.14.254137.76.14.255254
16137.76.15.0/24137.76.15.1 to 137.76.15.254137.76.15.255254
17137.76.16.0/24137.76.16.1 to 137.76.16.254137.76.16.255254
18137.76.17.0/24137.76.17.1 to 137.76.17.254137.76.17.255254
19137.76.18.0/24137.76.18.1 to 137.76.18.254137.76.18.255254
20137.76.19.0/24137.76.19.1 to 137.76.19.254137.76.19.255254
21137.76.20.0/24137.76.20.1 to 137.76.20.254137.76.20.255254
22137.76.21.0/24137.76.21.1 to 137.76.21.254137.76.21.255254
23137.76.22.0/24137.76.22.1 to 137.76.22.254137.76.22.255254
24137.76.23.0/24137.76.23.1 to 137.76.23.254137.76.23.255254
25137.76.24.0/24137.76.24.1 to 137.76.24.254137.76.24.255254
26137.76.25.0/24137.76.25.1 to 137.76.25.254137.76.25.255254
27137.76.26.0/24137.76.26.1 to 137.76.26.254137.76.26.255254
28137.76.27.0/24137.76.27.1 to 137.76.27.254137.76.27.255254
29137.76.28.0/24137.76.28.1 to 137.76.28.254137.76.28.255254
30137.76.29.0/24137.76.29.1 to 137.76.29.254137.76.29.255254
31137.76.30.0/24137.76.30.1 to 137.76.30.254137.76.30.255254
32137.76.31.0/24137.76.31.1 to 137.76.31.254137.76.31.255254
33137.76.32.0/24137.76.32.1 to 137.76.32.254137.76.32.255254
34137.76.33.0/24137.76.33.1 to 137.76.33.254137.76.33.255254
35137.76.34.0/24137.76.34.1 to 137.76.34.254137.76.34.255254
36137.76.35.0/24137.76.35.1 to 137.76.35.254137.76.35.255254
37137.76.36.0/24137.76.36.1 to 137.76.36.254137.76.36.255254
38137.76.37.0/24137.76.37.1 to 137.76.37.254137.76.37.255254
39137.76.38.0/24137.76.38.1 to 137.76.38.254137.76.38.255254
40137.76.39.0/24137.76.39.1 to 137.76.39.254137.76.39.255254
41137.76.40.0/24137.76.40.1 to 137.76.40.254137.76.40.255254
42137.76.41.0/24137.76.41.1 to 137.76.41.254137.76.41.255254
43137.76.42.0/24137.76.42.1 to 137.76.42.254137.76.42.255254
44137.76.43.0/24137.76.43.1 to 137.76.43.254137.76.43.255254
45137.76.44.0/24137.76.44.1 to 137.76.44.254137.76.44.255254
46137.76.45.0/24137.76.45.1 to 137.76.45.254137.76.45.255254
47137.76.46.0/24137.76.46.1 to 137.76.46.254137.76.46.255254
48137.76.47.0/24137.76.47.1 to 137.76.47.254137.76.47.255254
49137.76.48.0/24137.76.48.1 to 137.76.48.254137.76.48.255254
50137.76.49.0/24137.76.49.1 to 137.76.49.254137.76.49.255254
51137.76.50.0/24137.76.50.1 to 137.76.50.254137.76.50.255254
52137.76.51.0/24137.76.51.1 to 137.76.51.254137.76.51.255254
53137.76.52.0/24137.76.52.1 to 137.76.52.254137.76.52.255254
54137.76.53.0/24137.76.53.1 to 137.76.53.254137.76.53.255254
55137.76.54.0/24137.76.54.1 to 137.76.54.254137.76.54.255254
56137.76.55.0/24137.76.55.1 to 137.76.55.254137.76.55.255254
57137.76.56.0/24137.76.56.1 to 137.76.56.254137.76.56.255254
58137.76.57.0/24137.76.57.1 to 137.76.57.254137.76.57.255254
59137.76.58.0/24137.76.58.1 to 137.76.58.254137.76.58.255254
60137.76.59.0/24137.76.59.1 to 137.76.59.254137.76.59.255254
61137.76.60.0/24137.76.60.1 to 137.76.60.254137.76.60.255254
62137.76.61.0/24137.76.61.1 to 137.76.61.254137.76.61.255254
63137.76.62.0/24137.76.62.1 to 137.76.62.254137.76.62.255254
64137.76.63.0/24137.76.63.1 to 137.76.63.254137.76.63.255254
65137.76.64.0/24137.76.64.1 to 137.76.64.254137.76.64.255254
66137.76.65.0/24137.76.65.1 to 137.76.65.254137.76.65.255254
67137.76.66.0/24137.76.66.1 to 137.76.66.254137.76.66.255254
68137.76.67.0/24137.76.67.1 to 137.76.67.254137.76.67.255254
69137.76.68.0/24137.76.68.1 to 137.76.68.254137.76.68.255254
70137.76.69.0/24137.76.69.1 to 137.76.69.254137.76.69.255254
71137.76.70.0/24137.76.70.1 to 137.76.70.254137.76.70.255254
72137.76.71.0/24137.76.71.1 to 137.76.71.254137.76.71.255254
73137.76.72.0/24137.76.72.1 to 137.76.72.254137.76.72.255254
74137.76.73.0/24137.76.73.1 to 137.76.73.254137.76.73.255254
75137.76.74.0/24137.76.74.1 to 137.76.74.254137.76.74.255254
76137.76.75.0/24137.76.75.1 to 137.76.75.254137.76.75.255254
77137.76.76.0/24137.76.76.1 to 137.76.76.254137.76.76.255254
78137.76.77.0/24137.76.77.1 to 137.76.77.254137.76.77.255254
79137.76.78.0/24137.76.78.1 to 137.76.78.254137.76.78.255254
80137.76.79.0/24137.76.79.1 to 137.76.79.254137.76.79.255254
81137.76.80.0/24137.76.80.1 to 137.76.80.254137.76.80.255254
82137.76.81.0/24137.76.81.1 to 137.76.81.254137.76.81.255254
83137.76.82.0/24137.76.82.1 to 137.76.82.254137.76.82.255254
84137.76.83.0/24137.76.83.1 to 137.76.83.254137.76.83.255254
85137.76.84.0/24137.76.84.1 to 137.76.84.254137.76.84.255254
86137.76.85.0/24137.76.85.1 to 137.76.85.254137.76.85.255254
87137.76.86.0/24137.76.86.1 to 137.76.86.254137.76.86.255254
88137.76.87.0/24137.76.87.1 to 137.76.87.254137.76.87.255254
89137.76.88.0/24137.76.88.1 to 137.76.88.254137.76.88.255254
90137.76.89.0/24137.76.89.1 to 137.76.89.254137.76.89.255254
91137.76.90.0/24137.76.90.1 to 137.76.90.254137.76.90.255254
92137.76.91.0/24137.76.91.1 to 137.76.91.254137.76.91.255254
93137.76.92.0/24137.76.92.1 to 137.76.92.254137.76.92.255254
94137.76.93.0/24137.76.93.1 to 137.76.93.254137.76.93.255254
95137.76.94.0/24137.76.94.1 to 137.76.94.254137.76.94.255254
96137.76.95.0/24137.76.95.1 to 137.76.95.254137.76.95.255254
97137.76.96.0/24137.76.96.1 to 137.76.96.254137.76.96.255254
98137.76.97.0/24137.76.97.1 to 137.76.97.254137.76.97.255254
99137.76.98.0/24137.76.98.1 to 137.76.98.254137.76.98.255254
100137.76.99.0/24137.76.99.1 to 137.76.99.254137.76.99.255254
101137.76.100.0/24137.76.100.1 to 137.76.100.254137.76.100.255254
102137.76.101.0/24137.76.101.1 to 137.76.101.254137.76.101.255254
103137.76.102.0/24137.76.102.1 to 137.76.102.254137.76.102.255254
104137.76.103.0/24137.76.103.1 to 137.76.103.254137.76.103.255254
105137.76.104.0/24137.76.104.1 to 137.76.104.254137.76.104.255254
106137.76.105.0/24137.76.105.1 to 137.76.105.254137.76.105.255254
107137.76.106.0/24137.76.106.1 to 137.76.106.254137.76.106.255254
108137.76.107.0/24137.76.107.1 to 137.76.107.254137.76.107.255254
109137.76.108.0/24137.76.108.1 to 137.76.108.254137.76.108.255254
110137.76.109.0/24137.76.109.1 to 137.76.109.254137.76.109.255254
111137.76.110.0/24137.76.110.1 to 137.76.110.254137.76.110.255254
112137.76.111.0/24137.76.111.1 to 137.76.111.254137.76.111.255254
113137.76.112.0/24137.76.112.1 to 137.76.112.254137.76.112.255254
114137.76.113.0/24137.76.113.1 to 137.76.113.254137.76.113.255254
115137.76.114.0/24137.76.114.1 to 137.76.114.254137.76.114.255254
116137.76.115.0/24137.76.115.1 to 137.76.115.254137.76.115.255254
117137.76.116.0/24137.76.116.1 to 137.76.116.254137.76.116.255254
118137.76.117.0/24137.76.117.1 to 137.76.117.254137.76.117.255254
119137.76.118.0/24137.76.118.1 to 137.76.118.254137.76.118.255254
120137.76.119.0/24137.76.119.1 to 137.76.119.254137.76.119.255254
121137.76.120.0/24137.76.120.1 to 137.76.120.254137.76.120.255254
122137.76.121.0/24137.76.121.1 to 137.76.121.254137.76.121.255254
123137.76.122.0/24137.76.122.1 to 137.76.122.254137.76.122.255254
124137.76.123.0/24137.76.123.1 to 137.76.123.254137.76.123.255254
125137.76.124.0/24137.76.124.1 to 137.76.124.254137.76.124.255254
126137.76.125.0/24137.76.125.1 to 137.76.125.254137.76.125.255254
127137.76.126.0/24137.76.126.1 to 137.76.126.254137.76.126.255254
128137.76.127.0/24137.76.127.1 to 137.76.127.254137.76.127.255254
129137.76.128.0/24137.76.128.1 to 137.76.128.254137.76.128.255254
130137.76.129.0/24137.76.129.1 to 137.76.129.254137.76.129.255254
131137.76.130.0/24137.76.130.1 to 137.76.130.254137.76.130.255254
132137.76.131.0/24137.76.131.1 to 137.76.131.254137.76.131.255254
133137.76.132.0/24137.76.132.1 to 137.76.132.254137.76.132.255254
134137.76.133.0/24137.76.133.1 to 137.76.133.254137.76.133.255254
135137.76.134.0/24137.76.134.1 to 137.76.134.254137.76.134.255254
136137.76.135.0/24137.76.135.1 to 137.76.135.254137.76.135.255254
137137.76.136.0/24137.76.136.1 to 137.76.136.254137.76.136.255254
138137.76.137.0/24137.76.137.1 to 137.76.137.254137.76.137.255254
139137.76.138.0/24137.76.138.1 to 137.76.138.254137.76.138.255254
140137.76.139.0/24137.76.139.1 to 137.76.139.254137.76.139.255254
141137.76.140.0/24137.76.140.1 to 137.76.140.254137.76.140.255254
142137.76.141.0/24137.76.141.1 to 137.76.141.254137.76.141.255254
143137.76.142.0/24137.76.142.1 to 137.76.142.254137.76.142.255254
144137.76.143.0/24137.76.143.1 to 137.76.143.254137.76.143.255254
145137.76.144.0/24137.76.144.1 to 137.76.144.254137.76.144.255254
146137.76.145.0/24137.76.145.1 to 137.76.145.254137.76.145.255254
147137.76.146.0/24137.76.146.1 to 137.76.146.254137.76.146.255254
148137.76.147.0/24137.76.147.1 to 137.76.147.254137.76.147.255254
149137.76.148.0/24137.76.148.1 to 137.76.148.254137.76.148.255254
150137.76.149.0/24137.76.149.1 to 137.76.149.254137.76.149.255254
151137.76.150.0/24137.76.150.1 to 137.76.150.254137.76.150.255254
152137.76.151.0/24137.76.151.1 to 137.76.151.254137.76.151.255254
153137.76.152.0/24137.76.152.1 to 137.76.152.254137.76.152.255254
154137.76.153.0/24137.76.153.1 to 137.76.153.254137.76.153.255254
155137.76.154.0/24137.76.154.1 to 137.76.154.254137.76.154.255254
156137.76.155.0/24137.76.155.1 to 137.76.155.254137.76.155.255254
157137.76.156.0/24137.76.156.1 to 137.76.156.254137.76.156.255254
158137.76.157.0/24137.76.157.1 to 137.76.157.254137.76.157.255254
159137.76.158.0/24137.76.158.1 to 137.76.158.254137.76.158.255254
160137.76.159.0/24137.76.159.1 to 137.76.159.254137.76.159.255254
161137.76.160.0/24137.76.160.1 to 137.76.160.254137.76.160.255254
162137.76.161.0/24137.76.161.1 to 137.76.161.254137.76.161.255254
163137.76.162.0/24137.76.162.1 to 137.76.162.254137.76.162.255254
164137.76.163.0/24137.76.163.1 to 137.76.163.254137.76.163.255254
165137.76.164.0/24137.76.164.1 to 137.76.164.254137.76.164.255254
166137.76.165.0/24137.76.165.1 to 137.76.165.254137.76.165.255254
167137.76.166.0/24137.76.166.1 to 137.76.166.254137.76.166.255254
168137.76.167.0/24137.76.167.1 to 137.76.167.254137.76.167.255254
169137.76.168.0/24137.76.168.1 to 137.76.168.254137.76.168.255254
170137.76.169.0/24137.76.169.1 to 137.76.169.254137.76.169.255254
171137.76.170.0/24137.76.170.1 to 137.76.170.254137.76.170.255254
172137.76.171.0/24137.76.171.1 to 137.76.171.254137.76.171.255254
173137.76.172.0/24137.76.172.1 to 137.76.172.254137.76.172.255254
174137.76.173.0/24137.76.173.1 to 137.76.173.254137.76.173.255254
175137.76.174.0/24137.76.174.1 to 137.76.174.254137.76.174.255254
176137.76.175.0/24137.76.175.1 to 137.76.175.254137.76.175.255254
177137.76.176.0/24137.76.176.1 to 137.76.176.254137.76.176.255254
178137.76.177.0/24137.76.177.1 to 137.76.177.254137.76.177.255254
179137.76.178.0/24137.76.178.1 to 137.76.178.254137.76.178.255254
180137.76.179.0/24137.76.179.1 to 137.76.179.254137.76.179.255254
181137.76.180.0/24137.76.180.1 to 137.76.180.254137.76.180.255254
182137.76.181.0/24137.76.181.1 to 137.76.181.254137.76.181.255254
183137.76.182.0/24137.76.182.1 to 137.76.182.254137.76.182.255254
184137.76.183.0/24137.76.183.1 to 137.76.183.254137.76.183.255254
185137.76.184.0/24137.76.184.1 to 137.76.184.254137.76.184.255254
186137.76.185.0/24137.76.185.1 to 137.76.185.254137.76.185.255254
187137.76.186.0/24137.76.186.1 to 137.76.186.254137.76.186.255254
188137.76.187.0/24137.76.187.1 to 137.76.187.254137.76.187.255254
189137.76.188.0/24137.76.188.1 to 137.76.188.254137.76.188.255254
190137.76.189.0/24137.76.189.1 to 137.76.189.254137.76.189.255254
191137.76.190.0/24137.76.190.1 to 137.76.190.254137.76.190.255254
192137.76.191.0/24137.76.191.1 to 137.76.191.254137.76.191.255254
193137.76.192.0/24137.76.192.1 to 137.76.192.254137.76.192.255254
194137.76.193.0/24137.76.193.1 to 137.76.193.254137.76.193.255254
195137.76.194.0/24137.76.194.1 to 137.76.194.254137.76.194.255254
196137.76.195.0/24137.76.195.1 to 137.76.195.254137.76.195.255254
197137.76.196.0/24137.76.196.1 to 137.76.196.254137.76.196.255254
198137.76.197.0/24137.76.197.1 to 137.76.197.254137.76.197.255254
199137.76.198.0/24137.76.198.1 to 137.76.198.254137.76.198.255254
200137.76.199.0/24137.76.199.1 to 137.76.199.254137.76.199.255254
201137.76.200.0/24137.76.200.1 to 137.76.200.254137.76.200.255254
202137.76.201.0/24137.76.201.1 to 137.76.201.254137.76.201.255254
203137.76.202.0/24137.76.202.1 to 137.76.202.254137.76.202.255254
204137.76.203.0/24137.76.203.1 to 137.76.203.254137.76.203.255254
205137.76.204.0/24137.76.204.1 to 137.76.204.254137.76.204.255254
206137.76.205.0/24137.76.205.1 to 137.76.205.254137.76.205.255254
207137.76.206.0/24137.76.206.1 to 137.76.206.254137.76.206.255254
208137.76.207.0/24137.76.207.1 to 137.76.207.254137.76.207.255254
209137.76.208.0/24137.76.208.1 to 137.76.208.254137.76.208.255254
210137.76.209.0/24137.76.209.1 to 137.76.209.254137.76.209.255254
211137.76.210.0/24137.76.210.1 to 137.76.210.254137.76.210.255254
212137.76.211.0/24137.76.211.1 to 137.76.211.254137.76.211.255254
213137.76.212.0/24137.76.212.1 to 137.76.212.254137.76.212.255254
214137.76.213.0/24137.76.213.1 to 137.76.213.254137.76.213.255254
215137.76.214.0/24137.76.214.1 to 137.76.214.254137.76.214.255254
216137.76.215.0/24137.76.215.1 to 137.76.215.254137.76.215.255254
217137.76.216.0/24137.76.216.1 to 137.76.216.254137.76.216.255254
218137.76.217.0/24137.76.217.1 to 137.76.217.254137.76.217.255254
219137.76.218.0/24137.76.218.1 to 137.76.218.254137.76.218.255254
220137.76.219.0/24137.76.219.1 to 137.76.219.254137.76.219.255254
221137.76.220.0/24137.76.220.1 to 137.76.220.254137.76.220.255254
222137.76.221.0/24137.76.221.1 to 137.76.221.254137.76.221.255254
223137.76.222.0/24137.76.222.1 to 137.76.222.254137.76.222.255254
224137.76.223.0/24137.76.223.1 to 137.76.223.254137.76.223.255254
225137.76.224.0/24137.76.224.1 to 137.76.224.254137.76.224.255254
226137.76.225.0/24137.76.225.1 to 137.76.225.254137.76.225.255254
227137.76.226.0/24137.76.226.1 to 137.76.226.254137.76.226.255254
228137.76.227.0/24137.76.227.1 to 137.76.227.254137.76.227.255254
229137.76.228.0/24137.76.228.1 to 137.76.228.254137.76.228.255254
230137.76.229.0/24137.76.229.1 to 137.76.229.254137.76.229.255254
231137.76.230.0/24137.76.230.1 to 137.76.230.254137.76.230.255254
232137.76.231.0/24137.76.231.1 to 137.76.231.254137.76.231.255254
233137.76.232.0/24137.76.232.1 to 137.76.232.254137.76.232.255254
234137.76.233.0/24137.76.233.1 to 137.76.233.254137.76.233.255254
235137.76.234.0/24137.76.234.1 to 137.76.234.254137.76.234.255254
236137.76.235.0/24137.76.235.1 to 137.76.235.254137.76.235.255254
237137.76.236.0/24137.76.236.1 to 137.76.236.254137.76.236.255254
238137.76.237.0/24137.76.237.1 to 137.76.237.254137.76.237.255254
239137.76.238.0/24137.76.238.1 to 137.76.238.254137.76.238.255254
240137.76.239.0/24137.76.239.1 to 137.76.239.254137.76.239.255254
241137.76.240.0/24137.76.240.1 to 137.76.240.254137.76.240.255254
242137.76.241.0/24137.76.241.1 to 137.76.241.254137.76.241.255254
243137.76.242.0/24137.76.242.1 to 137.76.242.254137.76.242.255254
244137.76.243.0/24137.76.243.1 to 137.76.243.254137.76.243.255254
245137.76.244.0/24137.76.244.1 to 137.76.244.254137.76.244.255254
246137.76.245.0/24137.76.245.1 to 137.76.245.254137.76.245.255254
247137.76.246.0/24137.76.246.1 to 137.76.246.254137.76.246.255254
248137.76.247.0/24137.76.247.1 to 137.76.247.254137.76.247.255254
249137.76.248.0/24137.76.248.1 to 137.76.248.254137.76.248.255254
250137.76.249.0/24137.76.249.1 to 137.76.249.254137.76.249.255254
251137.76.250.0/24137.76.250.1 to 137.76.250.254137.76.250.255254
252137.76.251.0/24137.76.251.1 to 137.76.251.254137.76.251.255254
253137.76.252.0/24137.76.252.1 to 137.76.252.254137.76.252.255254
254137.76.253.0/24137.76.253.1 to 137.76.253.254137.76.253.255254
255137.76.254.0/24137.76.254.1 to 137.76.254.254137.76.254.255254
256137.76.255.0/24137.76.255.1 to 137.76.255.254137.76.255.255254

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.