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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.

Network148.76.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
148.76.0.0
Broadcast address
148.79.255.255
First usable
148.76.0.1
Last usable
148.79.255.254
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 944C0000 · Integer 2488008704 to 2488270847
Reverse DNS zones
76.148.in-addr.arpa
77.148.in-addr.arpa
78.148.in-addr.arpa
79.148.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
Address10010100.01001100.00000000.00000000148.76.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10010100.01001100.00000000.00000000148.76.0.0
Broadcast10010100.01001111.11111111.11111111148.79.255.255
Split into smaller subnets/23
/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)

148.76.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1148.76.0.0/23148.76.0.1 to 148.76.1.254148.76.1.255510
2148.76.2.0/23148.76.2.1 to 148.76.3.254148.76.3.255510
3148.76.4.0/23148.76.4.1 to 148.76.5.254148.76.5.255510
4148.76.6.0/23148.76.6.1 to 148.76.7.254148.76.7.255510
5148.76.8.0/23148.76.8.1 to 148.76.9.254148.76.9.255510
6148.76.10.0/23148.76.10.1 to 148.76.11.254148.76.11.255510
7148.76.12.0/23148.76.12.1 to 148.76.13.254148.76.13.255510
8148.76.14.0/23148.76.14.1 to 148.76.15.254148.76.15.255510
9148.76.16.0/23148.76.16.1 to 148.76.17.254148.76.17.255510
10148.76.18.0/23148.76.18.1 to 148.76.19.254148.76.19.255510
11148.76.20.0/23148.76.20.1 to 148.76.21.254148.76.21.255510
12148.76.22.0/23148.76.22.1 to 148.76.23.254148.76.23.255510
13148.76.24.0/23148.76.24.1 to 148.76.25.254148.76.25.255510
14148.76.26.0/23148.76.26.1 to 148.76.27.254148.76.27.255510
15148.76.28.0/23148.76.28.1 to 148.76.29.254148.76.29.255510
16148.76.30.0/23148.76.30.1 to 148.76.31.254148.76.31.255510
17148.76.32.0/23148.76.32.1 to 148.76.33.254148.76.33.255510
18148.76.34.0/23148.76.34.1 to 148.76.35.254148.76.35.255510
19148.76.36.0/23148.76.36.1 to 148.76.37.254148.76.37.255510
20148.76.38.0/23148.76.38.1 to 148.76.39.254148.76.39.255510
21148.76.40.0/23148.76.40.1 to 148.76.41.254148.76.41.255510
22148.76.42.0/23148.76.42.1 to 148.76.43.254148.76.43.255510
23148.76.44.0/23148.76.44.1 to 148.76.45.254148.76.45.255510
24148.76.46.0/23148.76.46.1 to 148.76.47.254148.76.47.255510
25148.76.48.0/23148.76.48.1 to 148.76.49.254148.76.49.255510
26148.76.50.0/23148.76.50.1 to 148.76.51.254148.76.51.255510
27148.76.52.0/23148.76.52.1 to 148.76.53.254148.76.53.255510
28148.76.54.0/23148.76.54.1 to 148.76.55.254148.76.55.255510
29148.76.56.0/23148.76.56.1 to 148.76.57.254148.76.57.255510
30148.76.58.0/23148.76.58.1 to 148.76.59.254148.76.59.255510
31148.76.60.0/23148.76.60.1 to 148.76.61.254148.76.61.255510
32148.76.62.0/23148.76.62.1 to 148.76.63.254148.76.63.255510
33148.76.64.0/23148.76.64.1 to 148.76.65.254148.76.65.255510
34148.76.66.0/23148.76.66.1 to 148.76.67.254148.76.67.255510
35148.76.68.0/23148.76.68.1 to 148.76.69.254148.76.69.255510
36148.76.70.0/23148.76.70.1 to 148.76.71.254148.76.71.255510
37148.76.72.0/23148.76.72.1 to 148.76.73.254148.76.73.255510
38148.76.74.0/23148.76.74.1 to 148.76.75.254148.76.75.255510
39148.76.76.0/23148.76.76.1 to 148.76.77.254148.76.77.255510
40148.76.78.0/23148.76.78.1 to 148.76.79.254148.76.79.255510
41148.76.80.0/23148.76.80.1 to 148.76.81.254148.76.81.255510
42148.76.82.0/23148.76.82.1 to 148.76.83.254148.76.83.255510
43148.76.84.0/23148.76.84.1 to 148.76.85.254148.76.85.255510
44148.76.86.0/23148.76.86.1 to 148.76.87.254148.76.87.255510
45148.76.88.0/23148.76.88.1 to 148.76.89.254148.76.89.255510
46148.76.90.0/23148.76.90.1 to 148.76.91.254148.76.91.255510
47148.76.92.0/23148.76.92.1 to 148.76.93.254148.76.93.255510
48148.76.94.0/23148.76.94.1 to 148.76.95.254148.76.95.255510
49148.76.96.0/23148.76.96.1 to 148.76.97.254148.76.97.255510
50148.76.98.0/23148.76.98.1 to 148.76.99.254148.76.99.255510
51148.76.100.0/23148.76.100.1 to 148.76.101.254148.76.101.255510
52148.76.102.0/23148.76.102.1 to 148.76.103.254148.76.103.255510
53148.76.104.0/23148.76.104.1 to 148.76.105.254148.76.105.255510
54148.76.106.0/23148.76.106.1 to 148.76.107.254148.76.107.255510
55148.76.108.0/23148.76.108.1 to 148.76.109.254148.76.109.255510
56148.76.110.0/23148.76.110.1 to 148.76.111.254148.76.111.255510
57148.76.112.0/23148.76.112.1 to 148.76.113.254148.76.113.255510
58148.76.114.0/23148.76.114.1 to 148.76.115.254148.76.115.255510
59148.76.116.0/23148.76.116.1 to 148.76.117.254148.76.117.255510
60148.76.118.0/23148.76.118.1 to 148.76.119.254148.76.119.255510
61148.76.120.0/23148.76.120.1 to 148.76.121.254148.76.121.255510
62148.76.122.0/23148.76.122.1 to 148.76.123.254148.76.123.255510
63148.76.124.0/23148.76.124.1 to 148.76.125.254148.76.125.255510
64148.76.126.0/23148.76.126.1 to 148.76.127.254148.76.127.255510
65148.76.128.0/23148.76.128.1 to 148.76.129.254148.76.129.255510
66148.76.130.0/23148.76.130.1 to 148.76.131.254148.76.131.255510
67148.76.132.0/23148.76.132.1 to 148.76.133.254148.76.133.255510
68148.76.134.0/23148.76.134.1 to 148.76.135.254148.76.135.255510
69148.76.136.0/23148.76.136.1 to 148.76.137.254148.76.137.255510
70148.76.138.0/23148.76.138.1 to 148.76.139.254148.76.139.255510
71148.76.140.0/23148.76.140.1 to 148.76.141.254148.76.141.255510
72148.76.142.0/23148.76.142.1 to 148.76.143.254148.76.143.255510
73148.76.144.0/23148.76.144.1 to 148.76.145.254148.76.145.255510
74148.76.146.0/23148.76.146.1 to 148.76.147.254148.76.147.255510
75148.76.148.0/23148.76.148.1 to 148.76.149.254148.76.149.255510
76148.76.150.0/23148.76.150.1 to 148.76.151.254148.76.151.255510
77148.76.152.0/23148.76.152.1 to 148.76.153.254148.76.153.255510
78148.76.154.0/23148.76.154.1 to 148.76.155.254148.76.155.255510
79148.76.156.0/23148.76.156.1 to 148.76.157.254148.76.157.255510
80148.76.158.0/23148.76.158.1 to 148.76.159.254148.76.159.255510
81148.76.160.0/23148.76.160.1 to 148.76.161.254148.76.161.255510
82148.76.162.0/23148.76.162.1 to 148.76.163.254148.76.163.255510
83148.76.164.0/23148.76.164.1 to 148.76.165.254148.76.165.255510
84148.76.166.0/23148.76.166.1 to 148.76.167.254148.76.167.255510
85148.76.168.0/23148.76.168.1 to 148.76.169.254148.76.169.255510
86148.76.170.0/23148.76.170.1 to 148.76.171.254148.76.171.255510
87148.76.172.0/23148.76.172.1 to 148.76.173.254148.76.173.255510
88148.76.174.0/23148.76.174.1 to 148.76.175.254148.76.175.255510
89148.76.176.0/23148.76.176.1 to 148.76.177.254148.76.177.255510
90148.76.178.0/23148.76.178.1 to 148.76.179.254148.76.179.255510
91148.76.180.0/23148.76.180.1 to 148.76.181.254148.76.181.255510
92148.76.182.0/23148.76.182.1 to 148.76.183.254148.76.183.255510
93148.76.184.0/23148.76.184.1 to 148.76.185.254148.76.185.255510
94148.76.186.0/23148.76.186.1 to 148.76.187.254148.76.187.255510
95148.76.188.0/23148.76.188.1 to 148.76.189.254148.76.189.255510
96148.76.190.0/23148.76.190.1 to 148.76.191.254148.76.191.255510
97148.76.192.0/23148.76.192.1 to 148.76.193.254148.76.193.255510
98148.76.194.0/23148.76.194.1 to 148.76.195.254148.76.195.255510
99148.76.196.0/23148.76.196.1 to 148.76.197.254148.76.197.255510
100148.76.198.0/23148.76.198.1 to 148.76.199.254148.76.199.255510
101148.76.200.0/23148.76.200.1 to 148.76.201.254148.76.201.255510
102148.76.202.0/23148.76.202.1 to 148.76.203.254148.76.203.255510
103148.76.204.0/23148.76.204.1 to 148.76.205.254148.76.205.255510
104148.76.206.0/23148.76.206.1 to 148.76.207.254148.76.207.255510
105148.76.208.0/23148.76.208.1 to 148.76.209.254148.76.209.255510
106148.76.210.0/23148.76.210.1 to 148.76.211.254148.76.211.255510
107148.76.212.0/23148.76.212.1 to 148.76.213.254148.76.213.255510
108148.76.214.0/23148.76.214.1 to 148.76.215.254148.76.215.255510
109148.76.216.0/23148.76.216.1 to 148.76.217.254148.76.217.255510
110148.76.218.0/23148.76.218.1 to 148.76.219.254148.76.219.255510
111148.76.220.0/23148.76.220.1 to 148.76.221.254148.76.221.255510
112148.76.222.0/23148.76.222.1 to 148.76.223.254148.76.223.255510
113148.76.224.0/23148.76.224.1 to 148.76.225.254148.76.225.255510
114148.76.226.0/23148.76.226.1 to 148.76.227.254148.76.227.255510
115148.76.228.0/23148.76.228.1 to 148.76.229.254148.76.229.255510
116148.76.230.0/23148.76.230.1 to 148.76.231.254148.76.231.255510
117148.76.232.0/23148.76.232.1 to 148.76.233.254148.76.233.255510
118148.76.234.0/23148.76.234.1 to 148.76.235.254148.76.235.255510
119148.76.236.0/23148.76.236.1 to 148.76.237.254148.76.237.255510
120148.76.238.0/23148.76.238.1 to 148.76.239.254148.76.239.255510
121148.76.240.0/23148.76.240.1 to 148.76.241.254148.76.241.255510
122148.76.242.0/23148.76.242.1 to 148.76.243.254148.76.243.255510
123148.76.244.0/23148.76.244.1 to 148.76.245.254148.76.245.255510
124148.76.246.0/23148.76.246.1 to 148.76.247.254148.76.247.255510
125148.76.248.0/23148.76.248.1 to 148.76.249.254148.76.249.255510
126148.76.250.0/23148.76.250.1 to 148.76.251.254148.76.251.255510
127148.76.252.0/23148.76.252.1 to 148.76.253.254148.76.253.255510
128148.76.254.0/23148.76.254.1 to 148.76.255.254148.76.255.255510
129148.77.0.0/23148.77.0.1 to 148.77.1.254148.77.1.255510
130148.77.2.0/23148.77.2.1 to 148.77.3.254148.77.3.255510
131148.77.4.0/23148.77.4.1 to 148.77.5.254148.77.5.255510
132148.77.6.0/23148.77.6.1 to 148.77.7.254148.77.7.255510
133148.77.8.0/23148.77.8.1 to 148.77.9.254148.77.9.255510
134148.77.10.0/23148.77.10.1 to 148.77.11.254148.77.11.255510
135148.77.12.0/23148.77.12.1 to 148.77.13.254148.77.13.255510
136148.77.14.0/23148.77.14.1 to 148.77.15.254148.77.15.255510
137148.77.16.0/23148.77.16.1 to 148.77.17.254148.77.17.255510
138148.77.18.0/23148.77.18.1 to 148.77.19.254148.77.19.255510
139148.77.20.0/23148.77.20.1 to 148.77.21.254148.77.21.255510
140148.77.22.0/23148.77.22.1 to 148.77.23.254148.77.23.255510
141148.77.24.0/23148.77.24.1 to 148.77.25.254148.77.25.255510
142148.77.26.0/23148.77.26.1 to 148.77.27.254148.77.27.255510
143148.77.28.0/23148.77.28.1 to 148.77.29.254148.77.29.255510
144148.77.30.0/23148.77.30.1 to 148.77.31.254148.77.31.255510
145148.77.32.0/23148.77.32.1 to 148.77.33.254148.77.33.255510
146148.77.34.0/23148.77.34.1 to 148.77.35.254148.77.35.255510
147148.77.36.0/23148.77.36.1 to 148.77.37.254148.77.37.255510
148148.77.38.0/23148.77.38.1 to 148.77.39.254148.77.39.255510
149148.77.40.0/23148.77.40.1 to 148.77.41.254148.77.41.255510
150148.77.42.0/23148.77.42.1 to 148.77.43.254148.77.43.255510
151148.77.44.0/23148.77.44.1 to 148.77.45.254148.77.45.255510
152148.77.46.0/23148.77.46.1 to 148.77.47.254148.77.47.255510
153148.77.48.0/23148.77.48.1 to 148.77.49.254148.77.49.255510
154148.77.50.0/23148.77.50.1 to 148.77.51.254148.77.51.255510
155148.77.52.0/23148.77.52.1 to 148.77.53.254148.77.53.255510
156148.77.54.0/23148.77.54.1 to 148.77.55.254148.77.55.255510
157148.77.56.0/23148.77.56.1 to 148.77.57.254148.77.57.255510
158148.77.58.0/23148.77.58.1 to 148.77.59.254148.77.59.255510
159148.77.60.0/23148.77.60.1 to 148.77.61.254148.77.61.255510
160148.77.62.0/23148.77.62.1 to 148.77.63.254148.77.63.255510
161148.77.64.0/23148.77.64.1 to 148.77.65.254148.77.65.255510
162148.77.66.0/23148.77.66.1 to 148.77.67.254148.77.67.255510
163148.77.68.0/23148.77.68.1 to 148.77.69.254148.77.69.255510
164148.77.70.0/23148.77.70.1 to 148.77.71.254148.77.71.255510
165148.77.72.0/23148.77.72.1 to 148.77.73.254148.77.73.255510
166148.77.74.0/23148.77.74.1 to 148.77.75.254148.77.75.255510
167148.77.76.0/23148.77.76.1 to 148.77.77.254148.77.77.255510
168148.77.78.0/23148.77.78.1 to 148.77.79.254148.77.79.255510
169148.77.80.0/23148.77.80.1 to 148.77.81.254148.77.81.255510
170148.77.82.0/23148.77.82.1 to 148.77.83.254148.77.83.255510
171148.77.84.0/23148.77.84.1 to 148.77.85.254148.77.85.255510
172148.77.86.0/23148.77.86.1 to 148.77.87.254148.77.87.255510
173148.77.88.0/23148.77.88.1 to 148.77.89.254148.77.89.255510
174148.77.90.0/23148.77.90.1 to 148.77.91.254148.77.91.255510
175148.77.92.0/23148.77.92.1 to 148.77.93.254148.77.93.255510
176148.77.94.0/23148.77.94.1 to 148.77.95.254148.77.95.255510
177148.77.96.0/23148.77.96.1 to 148.77.97.254148.77.97.255510
178148.77.98.0/23148.77.98.1 to 148.77.99.254148.77.99.255510
179148.77.100.0/23148.77.100.1 to 148.77.101.254148.77.101.255510
180148.77.102.0/23148.77.102.1 to 148.77.103.254148.77.103.255510
181148.77.104.0/23148.77.104.1 to 148.77.105.254148.77.105.255510
182148.77.106.0/23148.77.106.1 to 148.77.107.254148.77.107.255510
183148.77.108.0/23148.77.108.1 to 148.77.109.254148.77.109.255510
184148.77.110.0/23148.77.110.1 to 148.77.111.254148.77.111.255510
185148.77.112.0/23148.77.112.1 to 148.77.113.254148.77.113.255510
186148.77.114.0/23148.77.114.1 to 148.77.115.254148.77.115.255510
187148.77.116.0/23148.77.116.1 to 148.77.117.254148.77.117.255510
188148.77.118.0/23148.77.118.1 to 148.77.119.254148.77.119.255510
189148.77.120.0/23148.77.120.1 to 148.77.121.254148.77.121.255510
190148.77.122.0/23148.77.122.1 to 148.77.123.254148.77.123.255510
191148.77.124.0/23148.77.124.1 to 148.77.125.254148.77.125.255510
192148.77.126.0/23148.77.126.1 to 148.77.127.254148.77.127.255510
193148.77.128.0/23148.77.128.1 to 148.77.129.254148.77.129.255510
194148.77.130.0/23148.77.130.1 to 148.77.131.254148.77.131.255510
195148.77.132.0/23148.77.132.1 to 148.77.133.254148.77.133.255510
196148.77.134.0/23148.77.134.1 to 148.77.135.254148.77.135.255510
197148.77.136.0/23148.77.136.1 to 148.77.137.254148.77.137.255510
198148.77.138.0/23148.77.138.1 to 148.77.139.254148.77.139.255510
199148.77.140.0/23148.77.140.1 to 148.77.141.254148.77.141.255510
200148.77.142.0/23148.77.142.1 to 148.77.143.254148.77.143.255510
201148.77.144.0/23148.77.144.1 to 148.77.145.254148.77.145.255510
202148.77.146.0/23148.77.146.1 to 148.77.147.254148.77.147.255510
203148.77.148.0/23148.77.148.1 to 148.77.149.254148.77.149.255510
204148.77.150.0/23148.77.150.1 to 148.77.151.254148.77.151.255510
205148.77.152.0/23148.77.152.1 to 148.77.153.254148.77.153.255510
206148.77.154.0/23148.77.154.1 to 148.77.155.254148.77.155.255510
207148.77.156.0/23148.77.156.1 to 148.77.157.254148.77.157.255510
208148.77.158.0/23148.77.158.1 to 148.77.159.254148.77.159.255510
209148.77.160.0/23148.77.160.1 to 148.77.161.254148.77.161.255510
210148.77.162.0/23148.77.162.1 to 148.77.163.254148.77.163.255510
211148.77.164.0/23148.77.164.1 to 148.77.165.254148.77.165.255510
212148.77.166.0/23148.77.166.1 to 148.77.167.254148.77.167.255510
213148.77.168.0/23148.77.168.1 to 148.77.169.254148.77.169.255510
214148.77.170.0/23148.77.170.1 to 148.77.171.254148.77.171.255510
215148.77.172.0/23148.77.172.1 to 148.77.173.254148.77.173.255510
216148.77.174.0/23148.77.174.1 to 148.77.175.254148.77.175.255510
217148.77.176.0/23148.77.176.1 to 148.77.177.254148.77.177.255510
218148.77.178.0/23148.77.178.1 to 148.77.179.254148.77.179.255510
219148.77.180.0/23148.77.180.1 to 148.77.181.254148.77.181.255510
220148.77.182.0/23148.77.182.1 to 148.77.183.254148.77.183.255510
221148.77.184.0/23148.77.184.1 to 148.77.185.254148.77.185.255510
222148.77.186.0/23148.77.186.1 to 148.77.187.254148.77.187.255510
223148.77.188.0/23148.77.188.1 to 148.77.189.254148.77.189.255510
224148.77.190.0/23148.77.190.1 to 148.77.191.254148.77.191.255510
225148.77.192.0/23148.77.192.1 to 148.77.193.254148.77.193.255510
226148.77.194.0/23148.77.194.1 to 148.77.195.254148.77.195.255510
227148.77.196.0/23148.77.196.1 to 148.77.197.254148.77.197.255510
228148.77.198.0/23148.77.198.1 to 148.77.199.254148.77.199.255510
229148.77.200.0/23148.77.200.1 to 148.77.201.254148.77.201.255510
230148.77.202.0/23148.77.202.1 to 148.77.203.254148.77.203.255510
231148.77.204.0/23148.77.204.1 to 148.77.205.254148.77.205.255510
232148.77.206.0/23148.77.206.1 to 148.77.207.254148.77.207.255510
233148.77.208.0/23148.77.208.1 to 148.77.209.254148.77.209.255510
234148.77.210.0/23148.77.210.1 to 148.77.211.254148.77.211.255510
235148.77.212.0/23148.77.212.1 to 148.77.213.254148.77.213.255510
236148.77.214.0/23148.77.214.1 to 148.77.215.254148.77.215.255510
237148.77.216.0/23148.77.216.1 to 148.77.217.254148.77.217.255510
238148.77.218.0/23148.77.218.1 to 148.77.219.254148.77.219.255510
239148.77.220.0/23148.77.220.1 to 148.77.221.254148.77.221.255510
240148.77.222.0/23148.77.222.1 to 148.77.223.254148.77.223.255510
241148.77.224.0/23148.77.224.1 to 148.77.225.254148.77.225.255510
242148.77.226.0/23148.77.226.1 to 148.77.227.254148.77.227.255510
243148.77.228.0/23148.77.228.1 to 148.77.229.254148.77.229.255510
244148.77.230.0/23148.77.230.1 to 148.77.231.254148.77.231.255510
245148.77.232.0/23148.77.232.1 to 148.77.233.254148.77.233.255510
246148.77.234.0/23148.77.234.1 to 148.77.235.254148.77.235.255510
247148.77.236.0/23148.77.236.1 to 148.77.237.254148.77.237.255510
248148.77.238.0/23148.77.238.1 to 148.77.239.254148.77.239.255510
249148.77.240.0/23148.77.240.1 to 148.77.241.254148.77.241.255510
250148.77.242.0/23148.77.242.1 to 148.77.243.254148.77.243.255510
251148.77.244.0/23148.77.244.1 to 148.77.245.254148.77.245.255510
252148.77.246.0/23148.77.246.1 to 148.77.247.254148.77.247.255510
253148.77.248.0/23148.77.248.1 to 148.77.249.254148.77.249.255510
254148.77.250.0/23148.77.250.1 to 148.77.251.254148.77.251.255510
255148.77.252.0/23148.77.252.1 to 148.77.253.254148.77.253.255510
256148.77.254.0/23148.77.254.1 to 148.77.255.254148.77.255.255510

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

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.