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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.

Network160.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
160.0.0.0
Broadcast address
161.255.255.255
First usable
160.0.0.1
Last usable
161.255.255.254
Usable hosts
33,554,430 (33,554,432 less the network and broadcast addresses)
Subnet mask
254.0.0.0
Wildcard mask
1.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/7
Type
Public public
Old class
B (default /16)
As numbers
Hex A0000000 · Integer 2684354560 to 2717908991
Reverse DNS zones
160.in-addr.arpa
161.in-addr.arpa
/7 is not on a 8-bit boundary, so it takes 2 /8 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10100000.00000000.00000000.00000000160.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network10100000.00000000.00000000.00000000160.0.0.0
Broadcast10100001.11111111.11111111.11111111161.255.255.255
Split into smaller subnets/16
/8 (2)/9 (4)/10 (8)/11 (16)/12 (32)/13 (64)/14 (128)/15 (256)/16 (512)/17 (1,024)/18 (2,048)/19 (4,096)

160.0.0.0/7 makes 512 subnets of /16; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1160.0.0.0/16160.0.0.1 to 160.0.255.254160.0.255.25565,534
2160.1.0.0/16160.1.0.1 to 160.1.255.254160.1.255.25565,534
3160.2.0.0/16160.2.0.1 to 160.2.255.254160.2.255.25565,534
4160.3.0.0/16160.3.0.1 to 160.3.255.254160.3.255.25565,534
5160.4.0.0/16160.4.0.1 to 160.4.255.254160.4.255.25565,534
6160.5.0.0/16160.5.0.1 to 160.5.255.254160.5.255.25565,534
7160.6.0.0/16160.6.0.1 to 160.6.255.254160.6.255.25565,534
8160.7.0.0/16160.7.0.1 to 160.7.255.254160.7.255.25565,534
9160.8.0.0/16160.8.0.1 to 160.8.255.254160.8.255.25565,534
10160.9.0.0/16160.9.0.1 to 160.9.255.254160.9.255.25565,534
11160.10.0.0/16160.10.0.1 to 160.10.255.254160.10.255.25565,534
12160.11.0.0/16160.11.0.1 to 160.11.255.254160.11.255.25565,534
13160.12.0.0/16160.12.0.1 to 160.12.255.254160.12.255.25565,534
14160.13.0.0/16160.13.0.1 to 160.13.255.254160.13.255.25565,534
15160.14.0.0/16160.14.0.1 to 160.14.255.254160.14.255.25565,534
16160.15.0.0/16160.15.0.1 to 160.15.255.254160.15.255.25565,534
17160.16.0.0/16160.16.0.1 to 160.16.255.254160.16.255.25565,534
18160.17.0.0/16160.17.0.1 to 160.17.255.254160.17.255.25565,534
19160.18.0.0/16160.18.0.1 to 160.18.255.254160.18.255.25565,534
20160.19.0.0/16160.19.0.1 to 160.19.255.254160.19.255.25565,534
21160.20.0.0/16160.20.0.1 to 160.20.255.254160.20.255.25565,534
22160.21.0.0/16160.21.0.1 to 160.21.255.254160.21.255.25565,534
23160.22.0.0/16160.22.0.1 to 160.22.255.254160.22.255.25565,534
24160.23.0.0/16160.23.0.1 to 160.23.255.254160.23.255.25565,534
25160.24.0.0/16160.24.0.1 to 160.24.255.254160.24.255.25565,534
26160.25.0.0/16160.25.0.1 to 160.25.255.254160.25.255.25565,534
27160.26.0.0/16160.26.0.1 to 160.26.255.254160.26.255.25565,534
28160.27.0.0/16160.27.0.1 to 160.27.255.254160.27.255.25565,534
29160.28.0.0/16160.28.0.1 to 160.28.255.254160.28.255.25565,534
30160.29.0.0/16160.29.0.1 to 160.29.255.254160.29.255.25565,534
31160.30.0.0/16160.30.0.1 to 160.30.255.254160.30.255.25565,534
32160.31.0.0/16160.31.0.1 to 160.31.255.254160.31.255.25565,534
33160.32.0.0/16160.32.0.1 to 160.32.255.254160.32.255.25565,534
34160.33.0.0/16160.33.0.1 to 160.33.255.254160.33.255.25565,534
35160.34.0.0/16160.34.0.1 to 160.34.255.254160.34.255.25565,534
36160.35.0.0/16160.35.0.1 to 160.35.255.254160.35.255.25565,534
37160.36.0.0/16160.36.0.1 to 160.36.255.254160.36.255.25565,534
38160.37.0.0/16160.37.0.1 to 160.37.255.254160.37.255.25565,534
39160.38.0.0/16160.38.0.1 to 160.38.255.254160.38.255.25565,534
40160.39.0.0/16160.39.0.1 to 160.39.255.254160.39.255.25565,534
41160.40.0.0/16160.40.0.1 to 160.40.255.254160.40.255.25565,534
42160.41.0.0/16160.41.0.1 to 160.41.255.254160.41.255.25565,534
43160.42.0.0/16160.42.0.1 to 160.42.255.254160.42.255.25565,534
44160.43.0.0/16160.43.0.1 to 160.43.255.254160.43.255.25565,534
45160.44.0.0/16160.44.0.1 to 160.44.255.254160.44.255.25565,534
46160.45.0.0/16160.45.0.1 to 160.45.255.254160.45.255.25565,534
47160.46.0.0/16160.46.0.1 to 160.46.255.254160.46.255.25565,534
48160.47.0.0/16160.47.0.1 to 160.47.255.254160.47.255.25565,534
49160.48.0.0/16160.48.0.1 to 160.48.255.254160.48.255.25565,534
50160.49.0.0/16160.49.0.1 to 160.49.255.254160.49.255.25565,534
51160.50.0.0/16160.50.0.1 to 160.50.255.254160.50.255.25565,534
52160.51.0.0/16160.51.0.1 to 160.51.255.254160.51.255.25565,534
53160.52.0.0/16160.52.0.1 to 160.52.255.254160.52.255.25565,534
54160.53.0.0/16160.53.0.1 to 160.53.255.254160.53.255.25565,534
55160.54.0.0/16160.54.0.1 to 160.54.255.254160.54.255.25565,534
56160.55.0.0/16160.55.0.1 to 160.55.255.254160.55.255.25565,534
57160.56.0.0/16160.56.0.1 to 160.56.255.254160.56.255.25565,534
58160.57.0.0/16160.57.0.1 to 160.57.255.254160.57.255.25565,534
59160.58.0.0/16160.58.0.1 to 160.58.255.254160.58.255.25565,534
60160.59.0.0/16160.59.0.1 to 160.59.255.254160.59.255.25565,534
61160.60.0.0/16160.60.0.1 to 160.60.255.254160.60.255.25565,534
62160.61.0.0/16160.61.0.1 to 160.61.255.254160.61.255.25565,534
63160.62.0.0/16160.62.0.1 to 160.62.255.254160.62.255.25565,534
64160.63.0.0/16160.63.0.1 to 160.63.255.254160.63.255.25565,534
65160.64.0.0/16160.64.0.1 to 160.64.255.254160.64.255.25565,534
66160.65.0.0/16160.65.0.1 to 160.65.255.254160.65.255.25565,534
67160.66.0.0/16160.66.0.1 to 160.66.255.254160.66.255.25565,534
68160.67.0.0/16160.67.0.1 to 160.67.255.254160.67.255.25565,534
69160.68.0.0/16160.68.0.1 to 160.68.255.254160.68.255.25565,534
70160.69.0.0/16160.69.0.1 to 160.69.255.254160.69.255.25565,534
71160.70.0.0/16160.70.0.1 to 160.70.255.254160.70.255.25565,534
72160.71.0.0/16160.71.0.1 to 160.71.255.254160.71.255.25565,534
73160.72.0.0/16160.72.0.1 to 160.72.255.254160.72.255.25565,534
74160.73.0.0/16160.73.0.1 to 160.73.255.254160.73.255.25565,534
75160.74.0.0/16160.74.0.1 to 160.74.255.254160.74.255.25565,534
76160.75.0.0/16160.75.0.1 to 160.75.255.254160.75.255.25565,534
77160.76.0.0/16160.76.0.1 to 160.76.255.254160.76.255.25565,534
78160.77.0.0/16160.77.0.1 to 160.77.255.254160.77.255.25565,534
79160.78.0.0/16160.78.0.1 to 160.78.255.254160.78.255.25565,534
80160.79.0.0/16160.79.0.1 to 160.79.255.254160.79.255.25565,534
81160.80.0.0/16160.80.0.1 to 160.80.255.254160.80.255.25565,534
82160.81.0.0/16160.81.0.1 to 160.81.255.254160.81.255.25565,534
83160.82.0.0/16160.82.0.1 to 160.82.255.254160.82.255.25565,534
84160.83.0.0/16160.83.0.1 to 160.83.255.254160.83.255.25565,534
85160.84.0.0/16160.84.0.1 to 160.84.255.254160.84.255.25565,534
86160.85.0.0/16160.85.0.1 to 160.85.255.254160.85.255.25565,534
87160.86.0.0/16160.86.0.1 to 160.86.255.254160.86.255.25565,534
88160.87.0.0/16160.87.0.1 to 160.87.255.254160.87.255.25565,534
89160.88.0.0/16160.88.0.1 to 160.88.255.254160.88.255.25565,534
90160.89.0.0/16160.89.0.1 to 160.89.255.254160.89.255.25565,534
91160.90.0.0/16160.90.0.1 to 160.90.255.254160.90.255.25565,534
92160.91.0.0/16160.91.0.1 to 160.91.255.254160.91.255.25565,534
93160.92.0.0/16160.92.0.1 to 160.92.255.254160.92.255.25565,534
94160.93.0.0/16160.93.0.1 to 160.93.255.254160.93.255.25565,534
95160.94.0.0/16160.94.0.1 to 160.94.255.254160.94.255.25565,534
96160.95.0.0/16160.95.0.1 to 160.95.255.254160.95.255.25565,534
97160.96.0.0/16160.96.0.1 to 160.96.255.254160.96.255.25565,534
98160.97.0.0/16160.97.0.1 to 160.97.255.254160.97.255.25565,534
99160.98.0.0/16160.98.0.1 to 160.98.255.254160.98.255.25565,534
100160.99.0.0/16160.99.0.1 to 160.99.255.254160.99.255.25565,534
101160.100.0.0/16160.100.0.1 to 160.100.255.254160.100.255.25565,534
102160.101.0.0/16160.101.0.1 to 160.101.255.254160.101.255.25565,534
103160.102.0.0/16160.102.0.1 to 160.102.255.254160.102.255.25565,534
104160.103.0.0/16160.103.0.1 to 160.103.255.254160.103.255.25565,534
105160.104.0.0/16160.104.0.1 to 160.104.255.254160.104.255.25565,534
106160.105.0.0/16160.105.0.1 to 160.105.255.254160.105.255.25565,534
107160.106.0.0/16160.106.0.1 to 160.106.255.254160.106.255.25565,534
108160.107.0.0/16160.107.0.1 to 160.107.255.254160.107.255.25565,534
109160.108.0.0/16160.108.0.1 to 160.108.255.254160.108.255.25565,534
110160.109.0.0/16160.109.0.1 to 160.109.255.254160.109.255.25565,534
111160.110.0.0/16160.110.0.1 to 160.110.255.254160.110.255.25565,534
112160.111.0.0/16160.111.0.1 to 160.111.255.254160.111.255.25565,534
113160.112.0.0/16160.112.0.1 to 160.112.255.254160.112.255.25565,534
114160.113.0.0/16160.113.0.1 to 160.113.255.254160.113.255.25565,534
115160.114.0.0/16160.114.0.1 to 160.114.255.254160.114.255.25565,534
116160.115.0.0/16160.115.0.1 to 160.115.255.254160.115.255.25565,534
117160.116.0.0/16160.116.0.1 to 160.116.255.254160.116.255.25565,534
118160.117.0.0/16160.117.0.1 to 160.117.255.254160.117.255.25565,534
119160.118.0.0/16160.118.0.1 to 160.118.255.254160.118.255.25565,534
120160.119.0.0/16160.119.0.1 to 160.119.255.254160.119.255.25565,534
121160.120.0.0/16160.120.0.1 to 160.120.255.254160.120.255.25565,534
122160.121.0.0/16160.121.0.1 to 160.121.255.254160.121.255.25565,534
123160.122.0.0/16160.122.0.1 to 160.122.255.254160.122.255.25565,534
124160.123.0.0/16160.123.0.1 to 160.123.255.254160.123.255.25565,534
125160.124.0.0/16160.124.0.1 to 160.124.255.254160.124.255.25565,534
126160.125.0.0/16160.125.0.1 to 160.125.255.254160.125.255.25565,534
127160.126.0.0/16160.126.0.1 to 160.126.255.254160.126.255.25565,534
128160.127.0.0/16160.127.0.1 to 160.127.255.254160.127.255.25565,534
129160.128.0.0/16160.128.0.1 to 160.128.255.254160.128.255.25565,534
130160.129.0.0/16160.129.0.1 to 160.129.255.254160.129.255.25565,534
131160.130.0.0/16160.130.0.1 to 160.130.255.254160.130.255.25565,534
132160.131.0.0/16160.131.0.1 to 160.131.255.254160.131.255.25565,534
133160.132.0.0/16160.132.0.1 to 160.132.255.254160.132.255.25565,534
134160.133.0.0/16160.133.0.1 to 160.133.255.254160.133.255.25565,534
135160.134.0.0/16160.134.0.1 to 160.134.255.254160.134.255.25565,534
136160.135.0.0/16160.135.0.1 to 160.135.255.254160.135.255.25565,534
137160.136.0.0/16160.136.0.1 to 160.136.255.254160.136.255.25565,534
138160.137.0.0/16160.137.0.1 to 160.137.255.254160.137.255.25565,534
139160.138.0.0/16160.138.0.1 to 160.138.255.254160.138.255.25565,534
140160.139.0.0/16160.139.0.1 to 160.139.255.254160.139.255.25565,534
141160.140.0.0/16160.140.0.1 to 160.140.255.254160.140.255.25565,534
142160.141.0.0/16160.141.0.1 to 160.141.255.254160.141.255.25565,534
143160.142.0.0/16160.142.0.1 to 160.142.255.254160.142.255.25565,534
144160.143.0.0/16160.143.0.1 to 160.143.255.254160.143.255.25565,534
145160.144.0.0/16160.144.0.1 to 160.144.255.254160.144.255.25565,534
146160.145.0.0/16160.145.0.1 to 160.145.255.254160.145.255.25565,534
147160.146.0.0/16160.146.0.1 to 160.146.255.254160.146.255.25565,534
148160.147.0.0/16160.147.0.1 to 160.147.255.254160.147.255.25565,534
149160.148.0.0/16160.148.0.1 to 160.148.255.254160.148.255.25565,534
150160.149.0.0/16160.149.0.1 to 160.149.255.254160.149.255.25565,534
151160.150.0.0/16160.150.0.1 to 160.150.255.254160.150.255.25565,534
152160.151.0.0/16160.151.0.1 to 160.151.255.254160.151.255.25565,534
153160.152.0.0/16160.152.0.1 to 160.152.255.254160.152.255.25565,534
154160.153.0.0/16160.153.0.1 to 160.153.255.254160.153.255.25565,534
155160.154.0.0/16160.154.0.1 to 160.154.255.254160.154.255.25565,534
156160.155.0.0/16160.155.0.1 to 160.155.255.254160.155.255.25565,534
157160.156.0.0/16160.156.0.1 to 160.156.255.254160.156.255.25565,534
158160.157.0.0/16160.157.0.1 to 160.157.255.254160.157.255.25565,534
159160.158.0.0/16160.158.0.1 to 160.158.255.254160.158.255.25565,534
160160.159.0.0/16160.159.0.1 to 160.159.255.254160.159.255.25565,534
161160.160.0.0/16160.160.0.1 to 160.160.255.254160.160.255.25565,534
162160.161.0.0/16160.161.0.1 to 160.161.255.254160.161.255.25565,534
163160.162.0.0/16160.162.0.1 to 160.162.255.254160.162.255.25565,534
164160.163.0.0/16160.163.0.1 to 160.163.255.254160.163.255.25565,534
165160.164.0.0/16160.164.0.1 to 160.164.255.254160.164.255.25565,534
166160.165.0.0/16160.165.0.1 to 160.165.255.254160.165.255.25565,534
167160.166.0.0/16160.166.0.1 to 160.166.255.254160.166.255.25565,534
168160.167.0.0/16160.167.0.1 to 160.167.255.254160.167.255.25565,534
169160.168.0.0/16160.168.0.1 to 160.168.255.254160.168.255.25565,534
170160.169.0.0/16160.169.0.1 to 160.169.255.254160.169.255.25565,534
171160.170.0.0/16160.170.0.1 to 160.170.255.254160.170.255.25565,534
172160.171.0.0/16160.171.0.1 to 160.171.255.254160.171.255.25565,534
173160.172.0.0/16160.172.0.1 to 160.172.255.254160.172.255.25565,534
174160.173.0.0/16160.173.0.1 to 160.173.255.254160.173.255.25565,534
175160.174.0.0/16160.174.0.1 to 160.174.255.254160.174.255.25565,534
176160.175.0.0/16160.175.0.1 to 160.175.255.254160.175.255.25565,534
177160.176.0.0/16160.176.0.1 to 160.176.255.254160.176.255.25565,534
178160.177.0.0/16160.177.0.1 to 160.177.255.254160.177.255.25565,534
179160.178.0.0/16160.178.0.1 to 160.178.255.254160.178.255.25565,534
180160.179.0.0/16160.179.0.1 to 160.179.255.254160.179.255.25565,534
181160.180.0.0/16160.180.0.1 to 160.180.255.254160.180.255.25565,534
182160.181.0.0/16160.181.0.1 to 160.181.255.254160.181.255.25565,534
183160.182.0.0/16160.182.0.1 to 160.182.255.254160.182.255.25565,534
184160.183.0.0/16160.183.0.1 to 160.183.255.254160.183.255.25565,534
185160.184.0.0/16160.184.0.1 to 160.184.255.254160.184.255.25565,534
186160.185.0.0/16160.185.0.1 to 160.185.255.254160.185.255.25565,534
187160.186.0.0/16160.186.0.1 to 160.186.255.254160.186.255.25565,534
188160.187.0.0/16160.187.0.1 to 160.187.255.254160.187.255.25565,534
189160.188.0.0/16160.188.0.1 to 160.188.255.254160.188.255.25565,534
190160.189.0.0/16160.189.0.1 to 160.189.255.254160.189.255.25565,534
191160.190.0.0/16160.190.0.1 to 160.190.255.254160.190.255.25565,534
192160.191.0.0/16160.191.0.1 to 160.191.255.254160.191.255.25565,534
193160.192.0.0/16160.192.0.1 to 160.192.255.254160.192.255.25565,534
194160.193.0.0/16160.193.0.1 to 160.193.255.254160.193.255.25565,534
195160.194.0.0/16160.194.0.1 to 160.194.255.254160.194.255.25565,534
196160.195.0.0/16160.195.0.1 to 160.195.255.254160.195.255.25565,534
197160.196.0.0/16160.196.0.1 to 160.196.255.254160.196.255.25565,534
198160.197.0.0/16160.197.0.1 to 160.197.255.254160.197.255.25565,534
199160.198.0.0/16160.198.0.1 to 160.198.255.254160.198.255.25565,534
200160.199.0.0/16160.199.0.1 to 160.199.255.254160.199.255.25565,534
201160.200.0.0/16160.200.0.1 to 160.200.255.254160.200.255.25565,534
202160.201.0.0/16160.201.0.1 to 160.201.255.254160.201.255.25565,534
203160.202.0.0/16160.202.0.1 to 160.202.255.254160.202.255.25565,534
204160.203.0.0/16160.203.0.1 to 160.203.255.254160.203.255.25565,534
205160.204.0.0/16160.204.0.1 to 160.204.255.254160.204.255.25565,534
206160.205.0.0/16160.205.0.1 to 160.205.255.254160.205.255.25565,534
207160.206.0.0/16160.206.0.1 to 160.206.255.254160.206.255.25565,534
208160.207.0.0/16160.207.0.1 to 160.207.255.254160.207.255.25565,534
209160.208.0.0/16160.208.0.1 to 160.208.255.254160.208.255.25565,534
210160.209.0.0/16160.209.0.1 to 160.209.255.254160.209.255.25565,534
211160.210.0.0/16160.210.0.1 to 160.210.255.254160.210.255.25565,534
212160.211.0.0/16160.211.0.1 to 160.211.255.254160.211.255.25565,534
213160.212.0.0/16160.212.0.1 to 160.212.255.254160.212.255.25565,534
214160.213.0.0/16160.213.0.1 to 160.213.255.254160.213.255.25565,534
215160.214.0.0/16160.214.0.1 to 160.214.255.254160.214.255.25565,534
216160.215.0.0/16160.215.0.1 to 160.215.255.254160.215.255.25565,534
217160.216.0.0/16160.216.0.1 to 160.216.255.254160.216.255.25565,534
218160.217.0.0/16160.217.0.1 to 160.217.255.254160.217.255.25565,534
219160.218.0.0/16160.218.0.1 to 160.218.255.254160.218.255.25565,534
220160.219.0.0/16160.219.0.1 to 160.219.255.254160.219.255.25565,534
221160.220.0.0/16160.220.0.1 to 160.220.255.254160.220.255.25565,534
222160.221.0.0/16160.221.0.1 to 160.221.255.254160.221.255.25565,534
223160.222.0.0/16160.222.0.1 to 160.222.255.254160.222.255.25565,534
224160.223.0.0/16160.223.0.1 to 160.223.255.254160.223.255.25565,534
225160.224.0.0/16160.224.0.1 to 160.224.255.254160.224.255.25565,534
226160.225.0.0/16160.225.0.1 to 160.225.255.254160.225.255.25565,534
227160.226.0.0/16160.226.0.1 to 160.226.255.254160.226.255.25565,534
228160.227.0.0/16160.227.0.1 to 160.227.255.254160.227.255.25565,534
229160.228.0.0/16160.228.0.1 to 160.228.255.254160.228.255.25565,534
230160.229.0.0/16160.229.0.1 to 160.229.255.254160.229.255.25565,534
231160.230.0.0/16160.230.0.1 to 160.230.255.254160.230.255.25565,534
232160.231.0.0/16160.231.0.1 to 160.231.255.254160.231.255.25565,534
233160.232.0.0/16160.232.0.1 to 160.232.255.254160.232.255.25565,534
234160.233.0.0/16160.233.0.1 to 160.233.255.254160.233.255.25565,534
235160.234.0.0/16160.234.0.1 to 160.234.255.254160.234.255.25565,534
236160.235.0.0/16160.235.0.1 to 160.235.255.254160.235.255.25565,534
237160.236.0.0/16160.236.0.1 to 160.236.255.254160.236.255.25565,534
238160.237.0.0/16160.237.0.1 to 160.237.255.254160.237.255.25565,534
239160.238.0.0/16160.238.0.1 to 160.238.255.254160.238.255.25565,534
240160.239.0.0/16160.239.0.1 to 160.239.255.254160.239.255.25565,534
241160.240.0.0/16160.240.0.1 to 160.240.255.254160.240.255.25565,534
242160.241.0.0/16160.241.0.1 to 160.241.255.254160.241.255.25565,534
243160.242.0.0/16160.242.0.1 to 160.242.255.254160.242.255.25565,534
244160.243.0.0/16160.243.0.1 to 160.243.255.254160.243.255.25565,534
245160.244.0.0/16160.244.0.1 to 160.244.255.254160.244.255.25565,534
246160.245.0.0/16160.245.0.1 to 160.245.255.254160.245.255.25565,534
247160.246.0.0/16160.246.0.1 to 160.246.255.254160.246.255.25565,534
248160.247.0.0/16160.247.0.1 to 160.247.255.254160.247.255.25565,534
249160.248.0.0/16160.248.0.1 to 160.248.255.254160.248.255.25565,534
250160.249.0.0/16160.249.0.1 to 160.249.255.254160.249.255.25565,534
251160.250.0.0/16160.250.0.1 to 160.250.255.254160.250.255.25565,534
252160.251.0.0/16160.251.0.1 to 160.251.255.254160.251.255.25565,534
253160.252.0.0/16160.252.0.1 to 160.252.255.254160.252.255.25565,534
254160.253.0.0/16160.253.0.1 to 160.253.255.254160.253.255.25565,534
255160.254.0.0/16160.254.0.1 to 160.254.255.254160.254.255.25565,534
256160.255.0.0/16160.255.0.1 to 160.255.255.254160.255.255.25565,534

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.