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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.

Network177.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
177.0.0.0
Broadcast address
177.255.255.255
First usable
177.0.0.1
Last usable
177.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
B (default /16)
As numbers
Hex B1000000 · Integer 2969567232 to 2986344447
Reverse DNS zone
177.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10110001..00000000.00000000.00000000177.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network10110001..00000000.00000000.00000000177.0.0.0
Broadcast10110001..11111111.11111111.11111111177.255.255.255
Split into smaller subnets/16
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

177.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1177.0.0.0/16177.0.0.1 to 177.0.255.254177.0.255.25565,534
2177.1.0.0/16177.1.0.1 to 177.1.255.254177.1.255.25565,534
3177.2.0.0/16177.2.0.1 to 177.2.255.254177.2.255.25565,534
4177.3.0.0/16177.3.0.1 to 177.3.255.254177.3.255.25565,534
5177.4.0.0/16177.4.0.1 to 177.4.255.254177.4.255.25565,534
6177.5.0.0/16177.5.0.1 to 177.5.255.254177.5.255.25565,534
7177.6.0.0/16177.6.0.1 to 177.6.255.254177.6.255.25565,534
8177.7.0.0/16177.7.0.1 to 177.7.255.254177.7.255.25565,534
9177.8.0.0/16177.8.0.1 to 177.8.255.254177.8.255.25565,534
10177.9.0.0/16177.9.0.1 to 177.9.255.254177.9.255.25565,534
11177.10.0.0/16177.10.0.1 to 177.10.255.254177.10.255.25565,534
12177.11.0.0/16177.11.0.1 to 177.11.255.254177.11.255.25565,534
13177.12.0.0/16177.12.0.1 to 177.12.255.254177.12.255.25565,534
14177.13.0.0/16177.13.0.1 to 177.13.255.254177.13.255.25565,534
15177.14.0.0/16177.14.0.1 to 177.14.255.254177.14.255.25565,534
16177.15.0.0/16177.15.0.1 to 177.15.255.254177.15.255.25565,534
17177.16.0.0/16177.16.0.1 to 177.16.255.254177.16.255.25565,534
18177.17.0.0/16177.17.0.1 to 177.17.255.254177.17.255.25565,534
19177.18.0.0/16177.18.0.1 to 177.18.255.254177.18.255.25565,534
20177.19.0.0/16177.19.0.1 to 177.19.255.254177.19.255.25565,534
21177.20.0.0/16177.20.0.1 to 177.20.255.254177.20.255.25565,534
22177.21.0.0/16177.21.0.1 to 177.21.255.254177.21.255.25565,534
23177.22.0.0/16177.22.0.1 to 177.22.255.254177.22.255.25565,534
24177.23.0.0/16177.23.0.1 to 177.23.255.254177.23.255.25565,534
25177.24.0.0/16177.24.0.1 to 177.24.255.254177.24.255.25565,534
26177.25.0.0/16177.25.0.1 to 177.25.255.254177.25.255.25565,534
27177.26.0.0/16177.26.0.1 to 177.26.255.254177.26.255.25565,534
28177.27.0.0/16177.27.0.1 to 177.27.255.254177.27.255.25565,534
29177.28.0.0/16177.28.0.1 to 177.28.255.254177.28.255.25565,534
30177.29.0.0/16177.29.0.1 to 177.29.255.254177.29.255.25565,534
31177.30.0.0/16177.30.0.1 to 177.30.255.254177.30.255.25565,534
32177.31.0.0/16177.31.0.1 to 177.31.255.254177.31.255.25565,534
33177.32.0.0/16177.32.0.1 to 177.32.255.254177.32.255.25565,534
34177.33.0.0/16177.33.0.1 to 177.33.255.254177.33.255.25565,534
35177.34.0.0/16177.34.0.1 to 177.34.255.254177.34.255.25565,534
36177.35.0.0/16177.35.0.1 to 177.35.255.254177.35.255.25565,534
37177.36.0.0/16177.36.0.1 to 177.36.255.254177.36.255.25565,534
38177.37.0.0/16177.37.0.1 to 177.37.255.254177.37.255.25565,534
39177.38.0.0/16177.38.0.1 to 177.38.255.254177.38.255.25565,534
40177.39.0.0/16177.39.0.1 to 177.39.255.254177.39.255.25565,534
41177.40.0.0/16177.40.0.1 to 177.40.255.254177.40.255.25565,534
42177.41.0.0/16177.41.0.1 to 177.41.255.254177.41.255.25565,534
43177.42.0.0/16177.42.0.1 to 177.42.255.254177.42.255.25565,534
44177.43.0.0/16177.43.0.1 to 177.43.255.254177.43.255.25565,534
45177.44.0.0/16177.44.0.1 to 177.44.255.254177.44.255.25565,534
46177.45.0.0/16177.45.0.1 to 177.45.255.254177.45.255.25565,534
47177.46.0.0/16177.46.0.1 to 177.46.255.254177.46.255.25565,534
48177.47.0.0/16177.47.0.1 to 177.47.255.254177.47.255.25565,534
49177.48.0.0/16177.48.0.1 to 177.48.255.254177.48.255.25565,534
50177.49.0.0/16177.49.0.1 to 177.49.255.254177.49.255.25565,534
51177.50.0.0/16177.50.0.1 to 177.50.255.254177.50.255.25565,534
52177.51.0.0/16177.51.0.1 to 177.51.255.254177.51.255.25565,534
53177.52.0.0/16177.52.0.1 to 177.52.255.254177.52.255.25565,534
54177.53.0.0/16177.53.0.1 to 177.53.255.254177.53.255.25565,534
55177.54.0.0/16177.54.0.1 to 177.54.255.254177.54.255.25565,534
56177.55.0.0/16177.55.0.1 to 177.55.255.254177.55.255.25565,534
57177.56.0.0/16177.56.0.1 to 177.56.255.254177.56.255.25565,534
58177.57.0.0/16177.57.0.1 to 177.57.255.254177.57.255.25565,534
59177.58.0.0/16177.58.0.1 to 177.58.255.254177.58.255.25565,534
60177.59.0.0/16177.59.0.1 to 177.59.255.254177.59.255.25565,534
61177.60.0.0/16177.60.0.1 to 177.60.255.254177.60.255.25565,534
62177.61.0.0/16177.61.0.1 to 177.61.255.254177.61.255.25565,534
63177.62.0.0/16177.62.0.1 to 177.62.255.254177.62.255.25565,534
64177.63.0.0/16177.63.0.1 to 177.63.255.254177.63.255.25565,534
65177.64.0.0/16177.64.0.1 to 177.64.255.254177.64.255.25565,534
66177.65.0.0/16177.65.0.1 to 177.65.255.254177.65.255.25565,534
67177.66.0.0/16177.66.0.1 to 177.66.255.254177.66.255.25565,534
68177.67.0.0/16177.67.0.1 to 177.67.255.254177.67.255.25565,534
69177.68.0.0/16177.68.0.1 to 177.68.255.254177.68.255.25565,534
70177.69.0.0/16177.69.0.1 to 177.69.255.254177.69.255.25565,534
71177.70.0.0/16177.70.0.1 to 177.70.255.254177.70.255.25565,534
72177.71.0.0/16177.71.0.1 to 177.71.255.254177.71.255.25565,534
73177.72.0.0/16177.72.0.1 to 177.72.255.254177.72.255.25565,534
74177.73.0.0/16177.73.0.1 to 177.73.255.254177.73.255.25565,534
75177.74.0.0/16177.74.0.1 to 177.74.255.254177.74.255.25565,534
76177.75.0.0/16177.75.0.1 to 177.75.255.254177.75.255.25565,534
77177.76.0.0/16177.76.0.1 to 177.76.255.254177.76.255.25565,534
78177.77.0.0/16177.77.0.1 to 177.77.255.254177.77.255.25565,534
79177.78.0.0/16177.78.0.1 to 177.78.255.254177.78.255.25565,534
80177.79.0.0/16177.79.0.1 to 177.79.255.254177.79.255.25565,534
81177.80.0.0/16177.80.0.1 to 177.80.255.254177.80.255.25565,534
82177.81.0.0/16177.81.0.1 to 177.81.255.254177.81.255.25565,534
83177.82.0.0/16177.82.0.1 to 177.82.255.254177.82.255.25565,534
84177.83.0.0/16177.83.0.1 to 177.83.255.254177.83.255.25565,534
85177.84.0.0/16177.84.0.1 to 177.84.255.254177.84.255.25565,534
86177.85.0.0/16177.85.0.1 to 177.85.255.254177.85.255.25565,534
87177.86.0.0/16177.86.0.1 to 177.86.255.254177.86.255.25565,534
88177.87.0.0/16177.87.0.1 to 177.87.255.254177.87.255.25565,534
89177.88.0.0/16177.88.0.1 to 177.88.255.254177.88.255.25565,534
90177.89.0.0/16177.89.0.1 to 177.89.255.254177.89.255.25565,534
91177.90.0.0/16177.90.0.1 to 177.90.255.254177.90.255.25565,534
92177.91.0.0/16177.91.0.1 to 177.91.255.254177.91.255.25565,534
93177.92.0.0/16177.92.0.1 to 177.92.255.254177.92.255.25565,534
94177.93.0.0/16177.93.0.1 to 177.93.255.254177.93.255.25565,534
95177.94.0.0/16177.94.0.1 to 177.94.255.254177.94.255.25565,534
96177.95.0.0/16177.95.0.1 to 177.95.255.254177.95.255.25565,534
97177.96.0.0/16177.96.0.1 to 177.96.255.254177.96.255.25565,534
98177.97.0.0/16177.97.0.1 to 177.97.255.254177.97.255.25565,534
99177.98.0.0/16177.98.0.1 to 177.98.255.254177.98.255.25565,534
100177.99.0.0/16177.99.0.1 to 177.99.255.254177.99.255.25565,534
101177.100.0.0/16177.100.0.1 to 177.100.255.254177.100.255.25565,534
102177.101.0.0/16177.101.0.1 to 177.101.255.254177.101.255.25565,534
103177.102.0.0/16177.102.0.1 to 177.102.255.254177.102.255.25565,534
104177.103.0.0/16177.103.0.1 to 177.103.255.254177.103.255.25565,534
105177.104.0.0/16177.104.0.1 to 177.104.255.254177.104.255.25565,534
106177.105.0.0/16177.105.0.1 to 177.105.255.254177.105.255.25565,534
107177.106.0.0/16177.106.0.1 to 177.106.255.254177.106.255.25565,534
108177.107.0.0/16177.107.0.1 to 177.107.255.254177.107.255.25565,534
109177.108.0.0/16177.108.0.1 to 177.108.255.254177.108.255.25565,534
110177.109.0.0/16177.109.0.1 to 177.109.255.254177.109.255.25565,534
111177.110.0.0/16177.110.0.1 to 177.110.255.254177.110.255.25565,534
112177.111.0.0/16177.111.0.1 to 177.111.255.254177.111.255.25565,534
113177.112.0.0/16177.112.0.1 to 177.112.255.254177.112.255.25565,534
114177.113.0.0/16177.113.0.1 to 177.113.255.254177.113.255.25565,534
115177.114.0.0/16177.114.0.1 to 177.114.255.254177.114.255.25565,534
116177.115.0.0/16177.115.0.1 to 177.115.255.254177.115.255.25565,534
117177.116.0.0/16177.116.0.1 to 177.116.255.254177.116.255.25565,534
118177.117.0.0/16177.117.0.1 to 177.117.255.254177.117.255.25565,534
119177.118.0.0/16177.118.0.1 to 177.118.255.254177.118.255.25565,534
120177.119.0.0/16177.119.0.1 to 177.119.255.254177.119.255.25565,534
121177.120.0.0/16177.120.0.1 to 177.120.255.254177.120.255.25565,534
122177.121.0.0/16177.121.0.1 to 177.121.255.254177.121.255.25565,534
123177.122.0.0/16177.122.0.1 to 177.122.255.254177.122.255.25565,534
124177.123.0.0/16177.123.0.1 to 177.123.255.254177.123.255.25565,534
125177.124.0.0/16177.124.0.1 to 177.124.255.254177.124.255.25565,534
126177.125.0.0/16177.125.0.1 to 177.125.255.254177.125.255.25565,534
127177.126.0.0/16177.126.0.1 to 177.126.255.254177.126.255.25565,534
128177.127.0.0/16177.127.0.1 to 177.127.255.254177.127.255.25565,534
129177.128.0.0/16177.128.0.1 to 177.128.255.254177.128.255.25565,534
130177.129.0.0/16177.129.0.1 to 177.129.255.254177.129.255.25565,534
131177.130.0.0/16177.130.0.1 to 177.130.255.254177.130.255.25565,534
132177.131.0.0/16177.131.0.1 to 177.131.255.254177.131.255.25565,534
133177.132.0.0/16177.132.0.1 to 177.132.255.254177.132.255.25565,534
134177.133.0.0/16177.133.0.1 to 177.133.255.254177.133.255.25565,534
135177.134.0.0/16177.134.0.1 to 177.134.255.254177.134.255.25565,534
136177.135.0.0/16177.135.0.1 to 177.135.255.254177.135.255.25565,534
137177.136.0.0/16177.136.0.1 to 177.136.255.254177.136.255.25565,534
138177.137.0.0/16177.137.0.1 to 177.137.255.254177.137.255.25565,534
139177.138.0.0/16177.138.0.1 to 177.138.255.254177.138.255.25565,534
140177.139.0.0/16177.139.0.1 to 177.139.255.254177.139.255.25565,534
141177.140.0.0/16177.140.0.1 to 177.140.255.254177.140.255.25565,534
142177.141.0.0/16177.141.0.1 to 177.141.255.254177.141.255.25565,534
143177.142.0.0/16177.142.0.1 to 177.142.255.254177.142.255.25565,534
144177.143.0.0/16177.143.0.1 to 177.143.255.254177.143.255.25565,534
145177.144.0.0/16177.144.0.1 to 177.144.255.254177.144.255.25565,534
146177.145.0.0/16177.145.0.1 to 177.145.255.254177.145.255.25565,534
147177.146.0.0/16177.146.0.1 to 177.146.255.254177.146.255.25565,534
148177.147.0.0/16177.147.0.1 to 177.147.255.254177.147.255.25565,534
149177.148.0.0/16177.148.0.1 to 177.148.255.254177.148.255.25565,534
150177.149.0.0/16177.149.0.1 to 177.149.255.254177.149.255.25565,534
151177.150.0.0/16177.150.0.1 to 177.150.255.254177.150.255.25565,534
152177.151.0.0/16177.151.0.1 to 177.151.255.254177.151.255.25565,534
153177.152.0.0/16177.152.0.1 to 177.152.255.254177.152.255.25565,534
154177.153.0.0/16177.153.0.1 to 177.153.255.254177.153.255.25565,534
155177.154.0.0/16177.154.0.1 to 177.154.255.254177.154.255.25565,534
156177.155.0.0/16177.155.0.1 to 177.155.255.254177.155.255.25565,534
157177.156.0.0/16177.156.0.1 to 177.156.255.254177.156.255.25565,534
158177.157.0.0/16177.157.0.1 to 177.157.255.254177.157.255.25565,534
159177.158.0.0/16177.158.0.1 to 177.158.255.254177.158.255.25565,534
160177.159.0.0/16177.159.0.1 to 177.159.255.254177.159.255.25565,534
161177.160.0.0/16177.160.0.1 to 177.160.255.254177.160.255.25565,534
162177.161.0.0/16177.161.0.1 to 177.161.255.254177.161.255.25565,534
163177.162.0.0/16177.162.0.1 to 177.162.255.254177.162.255.25565,534
164177.163.0.0/16177.163.0.1 to 177.163.255.254177.163.255.25565,534
165177.164.0.0/16177.164.0.1 to 177.164.255.254177.164.255.25565,534
166177.165.0.0/16177.165.0.1 to 177.165.255.254177.165.255.25565,534
167177.166.0.0/16177.166.0.1 to 177.166.255.254177.166.255.25565,534
168177.167.0.0/16177.167.0.1 to 177.167.255.254177.167.255.25565,534
169177.168.0.0/16177.168.0.1 to 177.168.255.254177.168.255.25565,534
170177.169.0.0/16177.169.0.1 to 177.169.255.254177.169.255.25565,534
171177.170.0.0/16177.170.0.1 to 177.170.255.254177.170.255.25565,534
172177.171.0.0/16177.171.0.1 to 177.171.255.254177.171.255.25565,534
173177.172.0.0/16177.172.0.1 to 177.172.255.254177.172.255.25565,534
174177.173.0.0/16177.173.0.1 to 177.173.255.254177.173.255.25565,534
175177.174.0.0/16177.174.0.1 to 177.174.255.254177.174.255.25565,534
176177.175.0.0/16177.175.0.1 to 177.175.255.254177.175.255.25565,534
177177.176.0.0/16177.176.0.1 to 177.176.255.254177.176.255.25565,534
178177.177.0.0/16177.177.0.1 to 177.177.255.254177.177.255.25565,534
179177.178.0.0/16177.178.0.1 to 177.178.255.254177.178.255.25565,534
180177.179.0.0/16177.179.0.1 to 177.179.255.254177.179.255.25565,534
181177.180.0.0/16177.180.0.1 to 177.180.255.254177.180.255.25565,534
182177.181.0.0/16177.181.0.1 to 177.181.255.254177.181.255.25565,534
183177.182.0.0/16177.182.0.1 to 177.182.255.254177.182.255.25565,534
184177.183.0.0/16177.183.0.1 to 177.183.255.254177.183.255.25565,534
185177.184.0.0/16177.184.0.1 to 177.184.255.254177.184.255.25565,534
186177.185.0.0/16177.185.0.1 to 177.185.255.254177.185.255.25565,534
187177.186.0.0/16177.186.0.1 to 177.186.255.254177.186.255.25565,534
188177.187.0.0/16177.187.0.1 to 177.187.255.254177.187.255.25565,534
189177.188.0.0/16177.188.0.1 to 177.188.255.254177.188.255.25565,534
190177.189.0.0/16177.189.0.1 to 177.189.255.254177.189.255.25565,534
191177.190.0.0/16177.190.0.1 to 177.190.255.254177.190.255.25565,534
192177.191.0.0/16177.191.0.1 to 177.191.255.254177.191.255.25565,534
193177.192.0.0/16177.192.0.1 to 177.192.255.254177.192.255.25565,534
194177.193.0.0/16177.193.0.1 to 177.193.255.254177.193.255.25565,534
195177.194.0.0/16177.194.0.1 to 177.194.255.254177.194.255.25565,534
196177.195.0.0/16177.195.0.1 to 177.195.255.254177.195.255.25565,534
197177.196.0.0/16177.196.0.1 to 177.196.255.254177.196.255.25565,534
198177.197.0.0/16177.197.0.1 to 177.197.255.254177.197.255.25565,534
199177.198.0.0/16177.198.0.1 to 177.198.255.254177.198.255.25565,534
200177.199.0.0/16177.199.0.1 to 177.199.255.254177.199.255.25565,534
201177.200.0.0/16177.200.0.1 to 177.200.255.254177.200.255.25565,534
202177.201.0.0/16177.201.0.1 to 177.201.255.254177.201.255.25565,534
203177.202.0.0/16177.202.0.1 to 177.202.255.254177.202.255.25565,534
204177.203.0.0/16177.203.0.1 to 177.203.255.254177.203.255.25565,534
205177.204.0.0/16177.204.0.1 to 177.204.255.254177.204.255.25565,534
206177.205.0.0/16177.205.0.1 to 177.205.255.254177.205.255.25565,534
207177.206.0.0/16177.206.0.1 to 177.206.255.254177.206.255.25565,534
208177.207.0.0/16177.207.0.1 to 177.207.255.254177.207.255.25565,534
209177.208.0.0/16177.208.0.1 to 177.208.255.254177.208.255.25565,534
210177.209.0.0/16177.209.0.1 to 177.209.255.254177.209.255.25565,534
211177.210.0.0/16177.210.0.1 to 177.210.255.254177.210.255.25565,534
212177.211.0.0/16177.211.0.1 to 177.211.255.254177.211.255.25565,534
213177.212.0.0/16177.212.0.1 to 177.212.255.254177.212.255.25565,534
214177.213.0.0/16177.213.0.1 to 177.213.255.254177.213.255.25565,534
215177.214.0.0/16177.214.0.1 to 177.214.255.254177.214.255.25565,534
216177.215.0.0/16177.215.0.1 to 177.215.255.254177.215.255.25565,534
217177.216.0.0/16177.216.0.1 to 177.216.255.254177.216.255.25565,534
218177.217.0.0/16177.217.0.1 to 177.217.255.254177.217.255.25565,534
219177.218.0.0/16177.218.0.1 to 177.218.255.254177.218.255.25565,534
220177.219.0.0/16177.219.0.1 to 177.219.255.254177.219.255.25565,534
221177.220.0.0/16177.220.0.1 to 177.220.255.254177.220.255.25565,534
222177.221.0.0/16177.221.0.1 to 177.221.255.254177.221.255.25565,534
223177.222.0.0/16177.222.0.1 to 177.222.255.254177.222.255.25565,534
224177.223.0.0/16177.223.0.1 to 177.223.255.254177.223.255.25565,534
225177.224.0.0/16177.224.0.1 to 177.224.255.254177.224.255.25565,534
226177.225.0.0/16177.225.0.1 to 177.225.255.254177.225.255.25565,534
227177.226.0.0/16177.226.0.1 to 177.226.255.254177.226.255.25565,534
228177.227.0.0/16177.227.0.1 to 177.227.255.254177.227.255.25565,534
229177.228.0.0/16177.228.0.1 to 177.228.255.254177.228.255.25565,534
230177.229.0.0/16177.229.0.1 to 177.229.255.254177.229.255.25565,534
231177.230.0.0/16177.230.0.1 to 177.230.255.254177.230.255.25565,534
232177.231.0.0/16177.231.0.1 to 177.231.255.254177.231.255.25565,534
233177.232.0.0/16177.232.0.1 to 177.232.255.254177.232.255.25565,534
234177.233.0.0/16177.233.0.1 to 177.233.255.254177.233.255.25565,534
235177.234.0.0/16177.234.0.1 to 177.234.255.254177.234.255.25565,534
236177.235.0.0/16177.235.0.1 to 177.235.255.254177.235.255.25565,534
237177.236.0.0/16177.236.0.1 to 177.236.255.254177.236.255.25565,534
238177.237.0.0/16177.237.0.1 to 177.237.255.254177.237.255.25565,534
239177.238.0.0/16177.238.0.1 to 177.238.255.254177.238.255.25565,534
240177.239.0.0/16177.239.0.1 to 177.239.255.254177.239.255.25565,534
241177.240.0.0/16177.240.0.1 to 177.240.255.254177.240.255.25565,534
242177.241.0.0/16177.241.0.1 to 177.241.255.254177.241.255.25565,534
243177.242.0.0/16177.242.0.1 to 177.242.255.254177.242.255.25565,534
244177.243.0.0/16177.243.0.1 to 177.243.255.254177.243.255.25565,534
245177.244.0.0/16177.244.0.1 to 177.244.255.254177.244.255.25565,534
246177.245.0.0/16177.245.0.1 to 177.245.255.254177.245.255.25565,534
247177.246.0.0/16177.246.0.1 to 177.246.255.254177.246.255.25565,534
248177.247.0.0/16177.247.0.1 to 177.247.255.254177.247.255.25565,534
249177.248.0.0/16177.248.0.1 to 177.248.255.254177.248.255.25565,534
250177.249.0.0/16177.249.0.1 to 177.249.255.254177.249.255.25565,534
251177.250.0.0/16177.250.0.1 to 177.250.255.254177.250.255.25565,534
252177.251.0.0/16177.251.0.1 to 177.251.255.254177.251.255.25565,534
253177.252.0.0/16177.252.0.1 to 177.252.255.254177.252.255.25565,534
254177.253.0.0/16177.253.0.1 to 177.253.255.254177.253.255.25565,534
255177.254.0.0/16177.254.0.1 to 177.254.255.254177.254.255.25565,534
256177.255.0.0/16177.255.0.1 to 177.255.255.254177.255.255.25565,534

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.