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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.

Network190.0.0.0/7
Usable hosts33,554,430
Subnet mask254.0.0.0
Addresses33,554,432
Network address
190.0.0.0
Broadcast address
191.255.255.255
First usable
190.0.0.1
Last usable
191.255.255.254
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 BE000000 · Integer 3187671040 to 3221225471
Reverse DNS zones
190.in-addr.arpa
191.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
Address10111110.00000000.00000000.00000000190.0.0.0
Subnet mask11111110.00000000.00000000.00000000254.0.0.0
Network10111110.00000000.00000000.00000000190.0.0.0
Broadcast10111111.11111111.11111111.11111111191.255.255.255
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)

190.0.0.0/7 makes 512 subnets of /16; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1190.0.0.0/16190.0.0.1 to 190.0.255.254190.0.255.25565,534
2190.1.0.0/16190.1.0.1 to 190.1.255.254190.1.255.25565,534
3190.2.0.0/16190.2.0.1 to 190.2.255.254190.2.255.25565,534
4190.3.0.0/16190.3.0.1 to 190.3.255.254190.3.255.25565,534
5190.4.0.0/16190.4.0.1 to 190.4.255.254190.4.255.25565,534
6190.5.0.0/16190.5.0.1 to 190.5.255.254190.5.255.25565,534
7190.6.0.0/16190.6.0.1 to 190.6.255.254190.6.255.25565,534
8190.7.0.0/16190.7.0.1 to 190.7.255.254190.7.255.25565,534
9190.8.0.0/16190.8.0.1 to 190.8.255.254190.8.255.25565,534
10190.9.0.0/16190.9.0.1 to 190.9.255.254190.9.255.25565,534
11190.10.0.0/16190.10.0.1 to 190.10.255.254190.10.255.25565,534
12190.11.0.0/16190.11.0.1 to 190.11.255.254190.11.255.25565,534
13190.12.0.0/16190.12.0.1 to 190.12.255.254190.12.255.25565,534
14190.13.0.0/16190.13.0.1 to 190.13.255.254190.13.255.25565,534
15190.14.0.0/16190.14.0.1 to 190.14.255.254190.14.255.25565,534
16190.15.0.0/16190.15.0.1 to 190.15.255.254190.15.255.25565,534
17190.16.0.0/16190.16.0.1 to 190.16.255.254190.16.255.25565,534
18190.17.0.0/16190.17.0.1 to 190.17.255.254190.17.255.25565,534
19190.18.0.0/16190.18.0.1 to 190.18.255.254190.18.255.25565,534
20190.19.0.0/16190.19.0.1 to 190.19.255.254190.19.255.25565,534
21190.20.0.0/16190.20.0.1 to 190.20.255.254190.20.255.25565,534
22190.21.0.0/16190.21.0.1 to 190.21.255.254190.21.255.25565,534
23190.22.0.0/16190.22.0.1 to 190.22.255.254190.22.255.25565,534
24190.23.0.0/16190.23.0.1 to 190.23.255.254190.23.255.25565,534
25190.24.0.0/16190.24.0.1 to 190.24.255.254190.24.255.25565,534
26190.25.0.0/16190.25.0.1 to 190.25.255.254190.25.255.25565,534
27190.26.0.0/16190.26.0.1 to 190.26.255.254190.26.255.25565,534
28190.27.0.0/16190.27.0.1 to 190.27.255.254190.27.255.25565,534
29190.28.0.0/16190.28.0.1 to 190.28.255.254190.28.255.25565,534
30190.29.0.0/16190.29.0.1 to 190.29.255.254190.29.255.25565,534
31190.30.0.0/16190.30.0.1 to 190.30.255.254190.30.255.25565,534
32190.31.0.0/16190.31.0.1 to 190.31.255.254190.31.255.25565,534
33190.32.0.0/16190.32.0.1 to 190.32.255.254190.32.255.25565,534
34190.33.0.0/16190.33.0.1 to 190.33.255.254190.33.255.25565,534
35190.34.0.0/16190.34.0.1 to 190.34.255.254190.34.255.25565,534
36190.35.0.0/16190.35.0.1 to 190.35.255.254190.35.255.25565,534
37190.36.0.0/16190.36.0.1 to 190.36.255.254190.36.255.25565,534
38190.37.0.0/16190.37.0.1 to 190.37.255.254190.37.255.25565,534
39190.38.0.0/16190.38.0.1 to 190.38.255.254190.38.255.25565,534
40190.39.0.0/16190.39.0.1 to 190.39.255.254190.39.255.25565,534
41190.40.0.0/16190.40.0.1 to 190.40.255.254190.40.255.25565,534
42190.41.0.0/16190.41.0.1 to 190.41.255.254190.41.255.25565,534
43190.42.0.0/16190.42.0.1 to 190.42.255.254190.42.255.25565,534
44190.43.0.0/16190.43.0.1 to 190.43.255.254190.43.255.25565,534
45190.44.0.0/16190.44.0.1 to 190.44.255.254190.44.255.25565,534
46190.45.0.0/16190.45.0.1 to 190.45.255.254190.45.255.25565,534
47190.46.0.0/16190.46.0.1 to 190.46.255.254190.46.255.25565,534
48190.47.0.0/16190.47.0.1 to 190.47.255.254190.47.255.25565,534
49190.48.0.0/16190.48.0.1 to 190.48.255.254190.48.255.25565,534
50190.49.0.0/16190.49.0.1 to 190.49.255.254190.49.255.25565,534
51190.50.0.0/16190.50.0.1 to 190.50.255.254190.50.255.25565,534
52190.51.0.0/16190.51.0.1 to 190.51.255.254190.51.255.25565,534
53190.52.0.0/16190.52.0.1 to 190.52.255.254190.52.255.25565,534
54190.53.0.0/16190.53.0.1 to 190.53.255.254190.53.255.25565,534
55190.54.0.0/16190.54.0.1 to 190.54.255.254190.54.255.25565,534
56190.55.0.0/16190.55.0.1 to 190.55.255.254190.55.255.25565,534
57190.56.0.0/16190.56.0.1 to 190.56.255.254190.56.255.25565,534
58190.57.0.0/16190.57.0.1 to 190.57.255.254190.57.255.25565,534
59190.58.0.0/16190.58.0.1 to 190.58.255.254190.58.255.25565,534
60190.59.0.0/16190.59.0.1 to 190.59.255.254190.59.255.25565,534
61190.60.0.0/16190.60.0.1 to 190.60.255.254190.60.255.25565,534
62190.61.0.0/16190.61.0.1 to 190.61.255.254190.61.255.25565,534
63190.62.0.0/16190.62.0.1 to 190.62.255.254190.62.255.25565,534
64190.63.0.0/16190.63.0.1 to 190.63.255.254190.63.255.25565,534
65190.64.0.0/16190.64.0.1 to 190.64.255.254190.64.255.25565,534
66190.65.0.0/16190.65.0.1 to 190.65.255.254190.65.255.25565,534
67190.66.0.0/16190.66.0.1 to 190.66.255.254190.66.255.25565,534
68190.67.0.0/16190.67.0.1 to 190.67.255.254190.67.255.25565,534
69190.68.0.0/16190.68.0.1 to 190.68.255.254190.68.255.25565,534
70190.69.0.0/16190.69.0.1 to 190.69.255.254190.69.255.25565,534
71190.70.0.0/16190.70.0.1 to 190.70.255.254190.70.255.25565,534
72190.71.0.0/16190.71.0.1 to 190.71.255.254190.71.255.25565,534
73190.72.0.0/16190.72.0.1 to 190.72.255.254190.72.255.25565,534
74190.73.0.0/16190.73.0.1 to 190.73.255.254190.73.255.25565,534
75190.74.0.0/16190.74.0.1 to 190.74.255.254190.74.255.25565,534
76190.75.0.0/16190.75.0.1 to 190.75.255.254190.75.255.25565,534
77190.76.0.0/16190.76.0.1 to 190.76.255.254190.76.255.25565,534
78190.77.0.0/16190.77.0.1 to 190.77.255.254190.77.255.25565,534
79190.78.0.0/16190.78.0.1 to 190.78.255.254190.78.255.25565,534
80190.79.0.0/16190.79.0.1 to 190.79.255.254190.79.255.25565,534
81190.80.0.0/16190.80.0.1 to 190.80.255.254190.80.255.25565,534
82190.81.0.0/16190.81.0.1 to 190.81.255.254190.81.255.25565,534
83190.82.0.0/16190.82.0.1 to 190.82.255.254190.82.255.25565,534
84190.83.0.0/16190.83.0.1 to 190.83.255.254190.83.255.25565,534
85190.84.0.0/16190.84.0.1 to 190.84.255.254190.84.255.25565,534
86190.85.0.0/16190.85.0.1 to 190.85.255.254190.85.255.25565,534
87190.86.0.0/16190.86.0.1 to 190.86.255.254190.86.255.25565,534
88190.87.0.0/16190.87.0.1 to 190.87.255.254190.87.255.25565,534
89190.88.0.0/16190.88.0.1 to 190.88.255.254190.88.255.25565,534
90190.89.0.0/16190.89.0.1 to 190.89.255.254190.89.255.25565,534
91190.90.0.0/16190.90.0.1 to 190.90.255.254190.90.255.25565,534
92190.91.0.0/16190.91.0.1 to 190.91.255.254190.91.255.25565,534
93190.92.0.0/16190.92.0.1 to 190.92.255.254190.92.255.25565,534
94190.93.0.0/16190.93.0.1 to 190.93.255.254190.93.255.25565,534
95190.94.0.0/16190.94.0.1 to 190.94.255.254190.94.255.25565,534
96190.95.0.0/16190.95.0.1 to 190.95.255.254190.95.255.25565,534
97190.96.0.0/16190.96.0.1 to 190.96.255.254190.96.255.25565,534
98190.97.0.0/16190.97.0.1 to 190.97.255.254190.97.255.25565,534
99190.98.0.0/16190.98.0.1 to 190.98.255.254190.98.255.25565,534
100190.99.0.0/16190.99.0.1 to 190.99.255.254190.99.255.25565,534
101190.100.0.0/16190.100.0.1 to 190.100.255.254190.100.255.25565,534
102190.101.0.0/16190.101.0.1 to 190.101.255.254190.101.255.25565,534
103190.102.0.0/16190.102.0.1 to 190.102.255.254190.102.255.25565,534
104190.103.0.0/16190.103.0.1 to 190.103.255.254190.103.255.25565,534
105190.104.0.0/16190.104.0.1 to 190.104.255.254190.104.255.25565,534
106190.105.0.0/16190.105.0.1 to 190.105.255.254190.105.255.25565,534
107190.106.0.0/16190.106.0.1 to 190.106.255.254190.106.255.25565,534
108190.107.0.0/16190.107.0.1 to 190.107.255.254190.107.255.25565,534
109190.108.0.0/16190.108.0.1 to 190.108.255.254190.108.255.25565,534
110190.109.0.0/16190.109.0.1 to 190.109.255.254190.109.255.25565,534
111190.110.0.0/16190.110.0.1 to 190.110.255.254190.110.255.25565,534
112190.111.0.0/16190.111.0.1 to 190.111.255.254190.111.255.25565,534
113190.112.0.0/16190.112.0.1 to 190.112.255.254190.112.255.25565,534
114190.113.0.0/16190.113.0.1 to 190.113.255.254190.113.255.25565,534
115190.114.0.0/16190.114.0.1 to 190.114.255.254190.114.255.25565,534
116190.115.0.0/16190.115.0.1 to 190.115.255.254190.115.255.25565,534
117190.116.0.0/16190.116.0.1 to 190.116.255.254190.116.255.25565,534
118190.117.0.0/16190.117.0.1 to 190.117.255.254190.117.255.25565,534
119190.118.0.0/16190.118.0.1 to 190.118.255.254190.118.255.25565,534
120190.119.0.0/16190.119.0.1 to 190.119.255.254190.119.255.25565,534
121190.120.0.0/16190.120.0.1 to 190.120.255.254190.120.255.25565,534
122190.121.0.0/16190.121.0.1 to 190.121.255.254190.121.255.25565,534
123190.122.0.0/16190.122.0.1 to 190.122.255.254190.122.255.25565,534
124190.123.0.0/16190.123.0.1 to 190.123.255.254190.123.255.25565,534
125190.124.0.0/16190.124.0.1 to 190.124.255.254190.124.255.25565,534
126190.125.0.0/16190.125.0.1 to 190.125.255.254190.125.255.25565,534
127190.126.0.0/16190.126.0.1 to 190.126.255.254190.126.255.25565,534
128190.127.0.0/16190.127.0.1 to 190.127.255.254190.127.255.25565,534
129190.128.0.0/16190.128.0.1 to 190.128.255.254190.128.255.25565,534
130190.129.0.0/16190.129.0.1 to 190.129.255.254190.129.255.25565,534
131190.130.0.0/16190.130.0.1 to 190.130.255.254190.130.255.25565,534
132190.131.0.0/16190.131.0.1 to 190.131.255.254190.131.255.25565,534
133190.132.0.0/16190.132.0.1 to 190.132.255.254190.132.255.25565,534
134190.133.0.0/16190.133.0.1 to 190.133.255.254190.133.255.25565,534
135190.134.0.0/16190.134.0.1 to 190.134.255.254190.134.255.25565,534
136190.135.0.0/16190.135.0.1 to 190.135.255.254190.135.255.25565,534
137190.136.0.0/16190.136.0.1 to 190.136.255.254190.136.255.25565,534
138190.137.0.0/16190.137.0.1 to 190.137.255.254190.137.255.25565,534
139190.138.0.0/16190.138.0.1 to 190.138.255.254190.138.255.25565,534
140190.139.0.0/16190.139.0.1 to 190.139.255.254190.139.255.25565,534
141190.140.0.0/16190.140.0.1 to 190.140.255.254190.140.255.25565,534
142190.141.0.0/16190.141.0.1 to 190.141.255.254190.141.255.25565,534
143190.142.0.0/16190.142.0.1 to 190.142.255.254190.142.255.25565,534
144190.143.0.0/16190.143.0.1 to 190.143.255.254190.143.255.25565,534
145190.144.0.0/16190.144.0.1 to 190.144.255.254190.144.255.25565,534
146190.145.0.0/16190.145.0.1 to 190.145.255.254190.145.255.25565,534
147190.146.0.0/16190.146.0.1 to 190.146.255.254190.146.255.25565,534
148190.147.0.0/16190.147.0.1 to 190.147.255.254190.147.255.25565,534
149190.148.0.0/16190.148.0.1 to 190.148.255.254190.148.255.25565,534
150190.149.0.0/16190.149.0.1 to 190.149.255.254190.149.255.25565,534
151190.150.0.0/16190.150.0.1 to 190.150.255.254190.150.255.25565,534
152190.151.0.0/16190.151.0.1 to 190.151.255.254190.151.255.25565,534
153190.152.0.0/16190.152.0.1 to 190.152.255.254190.152.255.25565,534
154190.153.0.0/16190.153.0.1 to 190.153.255.254190.153.255.25565,534
155190.154.0.0/16190.154.0.1 to 190.154.255.254190.154.255.25565,534
156190.155.0.0/16190.155.0.1 to 190.155.255.254190.155.255.25565,534
157190.156.0.0/16190.156.0.1 to 190.156.255.254190.156.255.25565,534
158190.157.0.0/16190.157.0.1 to 190.157.255.254190.157.255.25565,534
159190.158.0.0/16190.158.0.1 to 190.158.255.254190.158.255.25565,534
160190.159.0.0/16190.159.0.1 to 190.159.255.254190.159.255.25565,534
161190.160.0.0/16190.160.0.1 to 190.160.255.254190.160.255.25565,534
162190.161.0.0/16190.161.0.1 to 190.161.255.254190.161.255.25565,534
163190.162.0.0/16190.162.0.1 to 190.162.255.254190.162.255.25565,534
164190.163.0.0/16190.163.0.1 to 190.163.255.254190.163.255.25565,534
165190.164.0.0/16190.164.0.1 to 190.164.255.254190.164.255.25565,534
166190.165.0.0/16190.165.0.1 to 190.165.255.254190.165.255.25565,534
167190.166.0.0/16190.166.0.1 to 190.166.255.254190.166.255.25565,534
168190.167.0.0/16190.167.0.1 to 190.167.255.254190.167.255.25565,534
169190.168.0.0/16190.168.0.1 to 190.168.255.254190.168.255.25565,534
170190.169.0.0/16190.169.0.1 to 190.169.255.254190.169.255.25565,534
171190.170.0.0/16190.170.0.1 to 190.170.255.254190.170.255.25565,534
172190.171.0.0/16190.171.0.1 to 190.171.255.254190.171.255.25565,534
173190.172.0.0/16190.172.0.1 to 190.172.255.254190.172.255.25565,534
174190.173.0.0/16190.173.0.1 to 190.173.255.254190.173.255.25565,534
175190.174.0.0/16190.174.0.1 to 190.174.255.254190.174.255.25565,534
176190.175.0.0/16190.175.0.1 to 190.175.255.254190.175.255.25565,534
177190.176.0.0/16190.176.0.1 to 190.176.255.254190.176.255.25565,534
178190.177.0.0/16190.177.0.1 to 190.177.255.254190.177.255.25565,534
179190.178.0.0/16190.178.0.1 to 190.178.255.254190.178.255.25565,534
180190.179.0.0/16190.179.0.1 to 190.179.255.254190.179.255.25565,534
181190.180.0.0/16190.180.0.1 to 190.180.255.254190.180.255.25565,534
182190.181.0.0/16190.181.0.1 to 190.181.255.254190.181.255.25565,534
183190.182.0.0/16190.182.0.1 to 190.182.255.254190.182.255.25565,534
184190.183.0.0/16190.183.0.1 to 190.183.255.254190.183.255.25565,534
185190.184.0.0/16190.184.0.1 to 190.184.255.254190.184.255.25565,534
186190.185.0.0/16190.185.0.1 to 190.185.255.254190.185.255.25565,534
187190.186.0.0/16190.186.0.1 to 190.186.255.254190.186.255.25565,534
188190.187.0.0/16190.187.0.1 to 190.187.255.254190.187.255.25565,534
189190.188.0.0/16190.188.0.1 to 190.188.255.254190.188.255.25565,534
190190.189.0.0/16190.189.0.1 to 190.189.255.254190.189.255.25565,534
191190.190.0.0/16190.190.0.1 to 190.190.255.254190.190.255.25565,534
192190.191.0.0/16190.191.0.1 to 190.191.255.254190.191.255.25565,534
193190.192.0.0/16190.192.0.1 to 190.192.255.254190.192.255.25565,534
194190.193.0.0/16190.193.0.1 to 190.193.255.254190.193.255.25565,534
195190.194.0.0/16190.194.0.1 to 190.194.255.254190.194.255.25565,534
196190.195.0.0/16190.195.0.1 to 190.195.255.254190.195.255.25565,534
197190.196.0.0/16190.196.0.1 to 190.196.255.254190.196.255.25565,534
198190.197.0.0/16190.197.0.1 to 190.197.255.254190.197.255.25565,534
199190.198.0.0/16190.198.0.1 to 190.198.255.254190.198.255.25565,534
200190.199.0.0/16190.199.0.1 to 190.199.255.254190.199.255.25565,534
201190.200.0.0/16190.200.0.1 to 190.200.255.254190.200.255.25565,534
202190.201.0.0/16190.201.0.1 to 190.201.255.254190.201.255.25565,534
203190.202.0.0/16190.202.0.1 to 190.202.255.254190.202.255.25565,534
204190.203.0.0/16190.203.0.1 to 190.203.255.254190.203.255.25565,534
205190.204.0.0/16190.204.0.1 to 190.204.255.254190.204.255.25565,534
206190.205.0.0/16190.205.0.1 to 190.205.255.254190.205.255.25565,534
207190.206.0.0/16190.206.0.1 to 190.206.255.254190.206.255.25565,534
208190.207.0.0/16190.207.0.1 to 190.207.255.254190.207.255.25565,534
209190.208.0.0/16190.208.0.1 to 190.208.255.254190.208.255.25565,534
210190.209.0.0/16190.209.0.1 to 190.209.255.254190.209.255.25565,534
211190.210.0.0/16190.210.0.1 to 190.210.255.254190.210.255.25565,534
212190.211.0.0/16190.211.0.1 to 190.211.255.254190.211.255.25565,534
213190.212.0.0/16190.212.0.1 to 190.212.255.254190.212.255.25565,534
214190.213.0.0/16190.213.0.1 to 190.213.255.254190.213.255.25565,534
215190.214.0.0/16190.214.0.1 to 190.214.255.254190.214.255.25565,534
216190.215.0.0/16190.215.0.1 to 190.215.255.254190.215.255.25565,534
217190.216.0.0/16190.216.0.1 to 190.216.255.254190.216.255.25565,534
218190.217.0.0/16190.217.0.1 to 190.217.255.254190.217.255.25565,534
219190.218.0.0/16190.218.0.1 to 190.218.255.254190.218.255.25565,534
220190.219.0.0/16190.219.0.1 to 190.219.255.254190.219.255.25565,534
221190.220.0.0/16190.220.0.1 to 190.220.255.254190.220.255.25565,534
222190.221.0.0/16190.221.0.1 to 190.221.255.254190.221.255.25565,534
223190.222.0.0/16190.222.0.1 to 190.222.255.254190.222.255.25565,534
224190.223.0.0/16190.223.0.1 to 190.223.255.254190.223.255.25565,534
225190.224.0.0/16190.224.0.1 to 190.224.255.254190.224.255.25565,534
226190.225.0.0/16190.225.0.1 to 190.225.255.254190.225.255.25565,534
227190.226.0.0/16190.226.0.1 to 190.226.255.254190.226.255.25565,534
228190.227.0.0/16190.227.0.1 to 190.227.255.254190.227.255.25565,534
229190.228.0.0/16190.228.0.1 to 190.228.255.254190.228.255.25565,534
230190.229.0.0/16190.229.0.1 to 190.229.255.254190.229.255.25565,534
231190.230.0.0/16190.230.0.1 to 190.230.255.254190.230.255.25565,534
232190.231.0.0/16190.231.0.1 to 190.231.255.254190.231.255.25565,534
233190.232.0.0/16190.232.0.1 to 190.232.255.254190.232.255.25565,534
234190.233.0.0/16190.233.0.1 to 190.233.255.254190.233.255.25565,534
235190.234.0.0/16190.234.0.1 to 190.234.255.254190.234.255.25565,534
236190.235.0.0/16190.235.0.1 to 190.235.255.254190.235.255.25565,534
237190.236.0.0/16190.236.0.1 to 190.236.255.254190.236.255.25565,534
238190.237.0.0/16190.237.0.1 to 190.237.255.254190.237.255.25565,534
239190.238.0.0/16190.238.0.1 to 190.238.255.254190.238.255.25565,534
240190.239.0.0/16190.239.0.1 to 190.239.255.254190.239.255.25565,534
241190.240.0.0/16190.240.0.1 to 190.240.255.254190.240.255.25565,534
242190.241.0.0/16190.241.0.1 to 190.241.255.254190.241.255.25565,534
243190.242.0.0/16190.242.0.1 to 190.242.255.254190.242.255.25565,534
244190.243.0.0/16190.243.0.1 to 190.243.255.254190.243.255.25565,534
245190.244.0.0/16190.244.0.1 to 190.244.255.254190.244.255.25565,534
246190.245.0.0/16190.245.0.1 to 190.245.255.254190.245.255.25565,534
247190.246.0.0/16190.246.0.1 to 190.246.255.254190.246.255.25565,534
248190.247.0.0/16190.247.0.1 to 190.247.255.254190.247.255.25565,534
249190.248.0.0/16190.248.0.1 to 190.248.255.254190.248.255.25565,534
250190.249.0.0/16190.249.0.1 to 190.249.255.254190.249.255.25565,534
251190.250.0.0/16190.250.0.1 to 190.250.255.254190.250.255.25565,534
252190.251.0.0/16190.251.0.1 to 190.251.255.254190.251.255.25565,534
253190.252.0.0/16190.252.0.1 to 190.252.255.254190.252.255.25565,534
254190.253.0.0/16190.253.0.1 to 190.253.255.254190.253.255.25565,534
255190.254.0.0/16190.254.0.1 to 190.254.255.254190.254.255.25565,534
256190.255.0.0/16190.255.0.1 to 190.255.255.254190.255.255.25565,534

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.