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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/18
/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 2,048 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1190.0.0.0/18190.0.0.1 to 190.0.63.254190.0.63.25516,382
2190.0.64.0/18190.0.64.1 to 190.0.127.254190.0.127.25516,382
3190.0.128.0/18190.0.128.1 to 190.0.191.254190.0.191.25516,382
4190.0.192.0/18190.0.192.1 to 190.0.255.254190.0.255.25516,382
5190.1.0.0/18190.1.0.1 to 190.1.63.254190.1.63.25516,382
6190.1.64.0/18190.1.64.1 to 190.1.127.254190.1.127.25516,382
7190.1.128.0/18190.1.128.1 to 190.1.191.254190.1.191.25516,382
8190.1.192.0/18190.1.192.1 to 190.1.255.254190.1.255.25516,382
9190.2.0.0/18190.2.0.1 to 190.2.63.254190.2.63.25516,382
10190.2.64.0/18190.2.64.1 to 190.2.127.254190.2.127.25516,382
11190.2.128.0/18190.2.128.1 to 190.2.191.254190.2.191.25516,382
12190.2.192.0/18190.2.192.1 to 190.2.255.254190.2.255.25516,382
13190.3.0.0/18190.3.0.1 to 190.3.63.254190.3.63.25516,382
14190.3.64.0/18190.3.64.1 to 190.3.127.254190.3.127.25516,382
15190.3.128.0/18190.3.128.1 to 190.3.191.254190.3.191.25516,382
16190.3.192.0/18190.3.192.1 to 190.3.255.254190.3.255.25516,382
17190.4.0.0/18190.4.0.1 to 190.4.63.254190.4.63.25516,382
18190.4.64.0/18190.4.64.1 to 190.4.127.254190.4.127.25516,382
19190.4.128.0/18190.4.128.1 to 190.4.191.254190.4.191.25516,382
20190.4.192.0/18190.4.192.1 to 190.4.255.254190.4.255.25516,382
21190.5.0.0/18190.5.0.1 to 190.5.63.254190.5.63.25516,382
22190.5.64.0/18190.5.64.1 to 190.5.127.254190.5.127.25516,382
23190.5.128.0/18190.5.128.1 to 190.5.191.254190.5.191.25516,382
24190.5.192.0/18190.5.192.1 to 190.5.255.254190.5.255.25516,382
25190.6.0.0/18190.6.0.1 to 190.6.63.254190.6.63.25516,382
26190.6.64.0/18190.6.64.1 to 190.6.127.254190.6.127.25516,382
27190.6.128.0/18190.6.128.1 to 190.6.191.254190.6.191.25516,382
28190.6.192.0/18190.6.192.1 to 190.6.255.254190.6.255.25516,382
29190.7.0.0/18190.7.0.1 to 190.7.63.254190.7.63.25516,382
30190.7.64.0/18190.7.64.1 to 190.7.127.254190.7.127.25516,382
31190.7.128.0/18190.7.128.1 to 190.7.191.254190.7.191.25516,382
32190.7.192.0/18190.7.192.1 to 190.7.255.254190.7.255.25516,382
33190.8.0.0/18190.8.0.1 to 190.8.63.254190.8.63.25516,382
34190.8.64.0/18190.8.64.1 to 190.8.127.254190.8.127.25516,382
35190.8.128.0/18190.8.128.1 to 190.8.191.254190.8.191.25516,382
36190.8.192.0/18190.8.192.1 to 190.8.255.254190.8.255.25516,382
37190.9.0.0/18190.9.0.1 to 190.9.63.254190.9.63.25516,382
38190.9.64.0/18190.9.64.1 to 190.9.127.254190.9.127.25516,382
39190.9.128.0/18190.9.128.1 to 190.9.191.254190.9.191.25516,382
40190.9.192.0/18190.9.192.1 to 190.9.255.254190.9.255.25516,382
41190.10.0.0/18190.10.0.1 to 190.10.63.254190.10.63.25516,382
42190.10.64.0/18190.10.64.1 to 190.10.127.254190.10.127.25516,382
43190.10.128.0/18190.10.128.1 to 190.10.191.254190.10.191.25516,382
44190.10.192.0/18190.10.192.1 to 190.10.255.254190.10.255.25516,382
45190.11.0.0/18190.11.0.1 to 190.11.63.254190.11.63.25516,382
46190.11.64.0/18190.11.64.1 to 190.11.127.254190.11.127.25516,382
47190.11.128.0/18190.11.128.1 to 190.11.191.254190.11.191.25516,382
48190.11.192.0/18190.11.192.1 to 190.11.255.254190.11.255.25516,382
49190.12.0.0/18190.12.0.1 to 190.12.63.254190.12.63.25516,382
50190.12.64.0/18190.12.64.1 to 190.12.127.254190.12.127.25516,382
51190.12.128.0/18190.12.128.1 to 190.12.191.254190.12.191.25516,382
52190.12.192.0/18190.12.192.1 to 190.12.255.254190.12.255.25516,382
53190.13.0.0/18190.13.0.1 to 190.13.63.254190.13.63.25516,382
54190.13.64.0/18190.13.64.1 to 190.13.127.254190.13.127.25516,382
55190.13.128.0/18190.13.128.1 to 190.13.191.254190.13.191.25516,382
56190.13.192.0/18190.13.192.1 to 190.13.255.254190.13.255.25516,382
57190.14.0.0/18190.14.0.1 to 190.14.63.254190.14.63.25516,382
58190.14.64.0/18190.14.64.1 to 190.14.127.254190.14.127.25516,382
59190.14.128.0/18190.14.128.1 to 190.14.191.254190.14.191.25516,382
60190.14.192.0/18190.14.192.1 to 190.14.255.254190.14.255.25516,382
61190.15.0.0/18190.15.0.1 to 190.15.63.254190.15.63.25516,382
62190.15.64.0/18190.15.64.1 to 190.15.127.254190.15.127.25516,382
63190.15.128.0/18190.15.128.1 to 190.15.191.254190.15.191.25516,382
64190.15.192.0/18190.15.192.1 to 190.15.255.254190.15.255.25516,382
65190.16.0.0/18190.16.0.1 to 190.16.63.254190.16.63.25516,382
66190.16.64.0/18190.16.64.1 to 190.16.127.254190.16.127.25516,382
67190.16.128.0/18190.16.128.1 to 190.16.191.254190.16.191.25516,382
68190.16.192.0/18190.16.192.1 to 190.16.255.254190.16.255.25516,382
69190.17.0.0/18190.17.0.1 to 190.17.63.254190.17.63.25516,382
70190.17.64.0/18190.17.64.1 to 190.17.127.254190.17.127.25516,382
71190.17.128.0/18190.17.128.1 to 190.17.191.254190.17.191.25516,382
72190.17.192.0/18190.17.192.1 to 190.17.255.254190.17.255.25516,382
73190.18.0.0/18190.18.0.1 to 190.18.63.254190.18.63.25516,382
74190.18.64.0/18190.18.64.1 to 190.18.127.254190.18.127.25516,382
75190.18.128.0/18190.18.128.1 to 190.18.191.254190.18.191.25516,382
76190.18.192.0/18190.18.192.1 to 190.18.255.254190.18.255.25516,382
77190.19.0.0/18190.19.0.1 to 190.19.63.254190.19.63.25516,382
78190.19.64.0/18190.19.64.1 to 190.19.127.254190.19.127.25516,382
79190.19.128.0/18190.19.128.1 to 190.19.191.254190.19.191.25516,382
80190.19.192.0/18190.19.192.1 to 190.19.255.254190.19.255.25516,382
81190.20.0.0/18190.20.0.1 to 190.20.63.254190.20.63.25516,382
82190.20.64.0/18190.20.64.1 to 190.20.127.254190.20.127.25516,382
83190.20.128.0/18190.20.128.1 to 190.20.191.254190.20.191.25516,382
84190.20.192.0/18190.20.192.1 to 190.20.255.254190.20.255.25516,382
85190.21.0.0/18190.21.0.1 to 190.21.63.254190.21.63.25516,382
86190.21.64.0/18190.21.64.1 to 190.21.127.254190.21.127.25516,382
87190.21.128.0/18190.21.128.1 to 190.21.191.254190.21.191.25516,382
88190.21.192.0/18190.21.192.1 to 190.21.255.254190.21.255.25516,382
89190.22.0.0/18190.22.0.1 to 190.22.63.254190.22.63.25516,382
90190.22.64.0/18190.22.64.1 to 190.22.127.254190.22.127.25516,382
91190.22.128.0/18190.22.128.1 to 190.22.191.254190.22.191.25516,382
92190.22.192.0/18190.22.192.1 to 190.22.255.254190.22.255.25516,382
93190.23.0.0/18190.23.0.1 to 190.23.63.254190.23.63.25516,382
94190.23.64.0/18190.23.64.1 to 190.23.127.254190.23.127.25516,382
95190.23.128.0/18190.23.128.1 to 190.23.191.254190.23.191.25516,382
96190.23.192.0/18190.23.192.1 to 190.23.255.254190.23.255.25516,382
97190.24.0.0/18190.24.0.1 to 190.24.63.254190.24.63.25516,382
98190.24.64.0/18190.24.64.1 to 190.24.127.254190.24.127.25516,382
99190.24.128.0/18190.24.128.1 to 190.24.191.254190.24.191.25516,382
100190.24.192.0/18190.24.192.1 to 190.24.255.254190.24.255.25516,382
101190.25.0.0/18190.25.0.1 to 190.25.63.254190.25.63.25516,382
102190.25.64.0/18190.25.64.1 to 190.25.127.254190.25.127.25516,382
103190.25.128.0/18190.25.128.1 to 190.25.191.254190.25.191.25516,382
104190.25.192.0/18190.25.192.1 to 190.25.255.254190.25.255.25516,382
105190.26.0.0/18190.26.0.1 to 190.26.63.254190.26.63.25516,382
106190.26.64.0/18190.26.64.1 to 190.26.127.254190.26.127.25516,382
107190.26.128.0/18190.26.128.1 to 190.26.191.254190.26.191.25516,382
108190.26.192.0/18190.26.192.1 to 190.26.255.254190.26.255.25516,382
109190.27.0.0/18190.27.0.1 to 190.27.63.254190.27.63.25516,382
110190.27.64.0/18190.27.64.1 to 190.27.127.254190.27.127.25516,382
111190.27.128.0/18190.27.128.1 to 190.27.191.254190.27.191.25516,382
112190.27.192.0/18190.27.192.1 to 190.27.255.254190.27.255.25516,382
113190.28.0.0/18190.28.0.1 to 190.28.63.254190.28.63.25516,382
114190.28.64.0/18190.28.64.1 to 190.28.127.254190.28.127.25516,382
115190.28.128.0/18190.28.128.1 to 190.28.191.254190.28.191.25516,382
116190.28.192.0/18190.28.192.1 to 190.28.255.254190.28.255.25516,382
117190.29.0.0/18190.29.0.1 to 190.29.63.254190.29.63.25516,382
118190.29.64.0/18190.29.64.1 to 190.29.127.254190.29.127.25516,382
119190.29.128.0/18190.29.128.1 to 190.29.191.254190.29.191.25516,382
120190.29.192.0/18190.29.192.1 to 190.29.255.254190.29.255.25516,382
121190.30.0.0/18190.30.0.1 to 190.30.63.254190.30.63.25516,382
122190.30.64.0/18190.30.64.1 to 190.30.127.254190.30.127.25516,382
123190.30.128.0/18190.30.128.1 to 190.30.191.254190.30.191.25516,382
124190.30.192.0/18190.30.192.1 to 190.30.255.254190.30.255.25516,382
125190.31.0.0/18190.31.0.1 to 190.31.63.254190.31.63.25516,382
126190.31.64.0/18190.31.64.1 to 190.31.127.254190.31.127.25516,382
127190.31.128.0/18190.31.128.1 to 190.31.191.254190.31.191.25516,382
128190.31.192.0/18190.31.192.1 to 190.31.255.254190.31.255.25516,382
129190.32.0.0/18190.32.0.1 to 190.32.63.254190.32.63.25516,382
130190.32.64.0/18190.32.64.1 to 190.32.127.254190.32.127.25516,382
131190.32.128.0/18190.32.128.1 to 190.32.191.254190.32.191.25516,382
132190.32.192.0/18190.32.192.1 to 190.32.255.254190.32.255.25516,382
133190.33.0.0/18190.33.0.1 to 190.33.63.254190.33.63.25516,382
134190.33.64.0/18190.33.64.1 to 190.33.127.254190.33.127.25516,382
135190.33.128.0/18190.33.128.1 to 190.33.191.254190.33.191.25516,382
136190.33.192.0/18190.33.192.1 to 190.33.255.254190.33.255.25516,382
137190.34.0.0/18190.34.0.1 to 190.34.63.254190.34.63.25516,382
138190.34.64.0/18190.34.64.1 to 190.34.127.254190.34.127.25516,382
139190.34.128.0/18190.34.128.1 to 190.34.191.254190.34.191.25516,382
140190.34.192.0/18190.34.192.1 to 190.34.255.254190.34.255.25516,382
141190.35.0.0/18190.35.0.1 to 190.35.63.254190.35.63.25516,382
142190.35.64.0/18190.35.64.1 to 190.35.127.254190.35.127.25516,382
143190.35.128.0/18190.35.128.1 to 190.35.191.254190.35.191.25516,382
144190.35.192.0/18190.35.192.1 to 190.35.255.254190.35.255.25516,382
145190.36.0.0/18190.36.0.1 to 190.36.63.254190.36.63.25516,382
146190.36.64.0/18190.36.64.1 to 190.36.127.254190.36.127.25516,382
147190.36.128.0/18190.36.128.1 to 190.36.191.254190.36.191.25516,382
148190.36.192.0/18190.36.192.1 to 190.36.255.254190.36.255.25516,382
149190.37.0.0/18190.37.0.1 to 190.37.63.254190.37.63.25516,382
150190.37.64.0/18190.37.64.1 to 190.37.127.254190.37.127.25516,382
151190.37.128.0/18190.37.128.1 to 190.37.191.254190.37.191.25516,382
152190.37.192.0/18190.37.192.1 to 190.37.255.254190.37.255.25516,382
153190.38.0.0/18190.38.0.1 to 190.38.63.254190.38.63.25516,382
154190.38.64.0/18190.38.64.1 to 190.38.127.254190.38.127.25516,382
155190.38.128.0/18190.38.128.1 to 190.38.191.254190.38.191.25516,382
156190.38.192.0/18190.38.192.1 to 190.38.255.254190.38.255.25516,382
157190.39.0.0/18190.39.0.1 to 190.39.63.254190.39.63.25516,382
158190.39.64.0/18190.39.64.1 to 190.39.127.254190.39.127.25516,382
159190.39.128.0/18190.39.128.1 to 190.39.191.254190.39.191.25516,382
160190.39.192.0/18190.39.192.1 to 190.39.255.254190.39.255.25516,382
161190.40.0.0/18190.40.0.1 to 190.40.63.254190.40.63.25516,382
162190.40.64.0/18190.40.64.1 to 190.40.127.254190.40.127.25516,382
163190.40.128.0/18190.40.128.1 to 190.40.191.254190.40.191.25516,382
164190.40.192.0/18190.40.192.1 to 190.40.255.254190.40.255.25516,382
165190.41.0.0/18190.41.0.1 to 190.41.63.254190.41.63.25516,382
166190.41.64.0/18190.41.64.1 to 190.41.127.254190.41.127.25516,382
167190.41.128.0/18190.41.128.1 to 190.41.191.254190.41.191.25516,382
168190.41.192.0/18190.41.192.1 to 190.41.255.254190.41.255.25516,382
169190.42.0.0/18190.42.0.1 to 190.42.63.254190.42.63.25516,382
170190.42.64.0/18190.42.64.1 to 190.42.127.254190.42.127.25516,382
171190.42.128.0/18190.42.128.1 to 190.42.191.254190.42.191.25516,382
172190.42.192.0/18190.42.192.1 to 190.42.255.254190.42.255.25516,382
173190.43.0.0/18190.43.0.1 to 190.43.63.254190.43.63.25516,382
174190.43.64.0/18190.43.64.1 to 190.43.127.254190.43.127.25516,382
175190.43.128.0/18190.43.128.1 to 190.43.191.254190.43.191.25516,382
176190.43.192.0/18190.43.192.1 to 190.43.255.254190.43.255.25516,382
177190.44.0.0/18190.44.0.1 to 190.44.63.254190.44.63.25516,382
178190.44.64.0/18190.44.64.1 to 190.44.127.254190.44.127.25516,382
179190.44.128.0/18190.44.128.1 to 190.44.191.254190.44.191.25516,382
180190.44.192.0/18190.44.192.1 to 190.44.255.254190.44.255.25516,382
181190.45.0.0/18190.45.0.1 to 190.45.63.254190.45.63.25516,382
182190.45.64.0/18190.45.64.1 to 190.45.127.254190.45.127.25516,382
183190.45.128.0/18190.45.128.1 to 190.45.191.254190.45.191.25516,382
184190.45.192.0/18190.45.192.1 to 190.45.255.254190.45.255.25516,382
185190.46.0.0/18190.46.0.1 to 190.46.63.254190.46.63.25516,382
186190.46.64.0/18190.46.64.1 to 190.46.127.254190.46.127.25516,382
187190.46.128.0/18190.46.128.1 to 190.46.191.254190.46.191.25516,382
188190.46.192.0/18190.46.192.1 to 190.46.255.254190.46.255.25516,382
189190.47.0.0/18190.47.0.1 to 190.47.63.254190.47.63.25516,382
190190.47.64.0/18190.47.64.1 to 190.47.127.254190.47.127.25516,382
191190.47.128.0/18190.47.128.1 to 190.47.191.254190.47.191.25516,382
192190.47.192.0/18190.47.192.1 to 190.47.255.254190.47.255.25516,382
193190.48.0.0/18190.48.0.1 to 190.48.63.254190.48.63.25516,382
194190.48.64.0/18190.48.64.1 to 190.48.127.254190.48.127.25516,382
195190.48.128.0/18190.48.128.1 to 190.48.191.254190.48.191.25516,382
196190.48.192.0/18190.48.192.1 to 190.48.255.254190.48.255.25516,382
197190.49.0.0/18190.49.0.1 to 190.49.63.254190.49.63.25516,382
198190.49.64.0/18190.49.64.1 to 190.49.127.254190.49.127.25516,382
199190.49.128.0/18190.49.128.1 to 190.49.191.254190.49.191.25516,382
200190.49.192.0/18190.49.192.1 to 190.49.255.254190.49.255.25516,382
201190.50.0.0/18190.50.0.1 to 190.50.63.254190.50.63.25516,382
202190.50.64.0/18190.50.64.1 to 190.50.127.254190.50.127.25516,382
203190.50.128.0/18190.50.128.1 to 190.50.191.254190.50.191.25516,382
204190.50.192.0/18190.50.192.1 to 190.50.255.254190.50.255.25516,382
205190.51.0.0/18190.51.0.1 to 190.51.63.254190.51.63.25516,382
206190.51.64.0/18190.51.64.1 to 190.51.127.254190.51.127.25516,382
207190.51.128.0/18190.51.128.1 to 190.51.191.254190.51.191.25516,382
208190.51.192.0/18190.51.192.1 to 190.51.255.254190.51.255.25516,382
209190.52.0.0/18190.52.0.1 to 190.52.63.254190.52.63.25516,382
210190.52.64.0/18190.52.64.1 to 190.52.127.254190.52.127.25516,382
211190.52.128.0/18190.52.128.1 to 190.52.191.254190.52.191.25516,382
212190.52.192.0/18190.52.192.1 to 190.52.255.254190.52.255.25516,382
213190.53.0.0/18190.53.0.1 to 190.53.63.254190.53.63.25516,382
214190.53.64.0/18190.53.64.1 to 190.53.127.254190.53.127.25516,382
215190.53.128.0/18190.53.128.1 to 190.53.191.254190.53.191.25516,382
216190.53.192.0/18190.53.192.1 to 190.53.255.254190.53.255.25516,382
217190.54.0.0/18190.54.0.1 to 190.54.63.254190.54.63.25516,382
218190.54.64.0/18190.54.64.1 to 190.54.127.254190.54.127.25516,382
219190.54.128.0/18190.54.128.1 to 190.54.191.254190.54.191.25516,382
220190.54.192.0/18190.54.192.1 to 190.54.255.254190.54.255.25516,382
221190.55.0.0/18190.55.0.1 to 190.55.63.254190.55.63.25516,382
222190.55.64.0/18190.55.64.1 to 190.55.127.254190.55.127.25516,382
223190.55.128.0/18190.55.128.1 to 190.55.191.254190.55.191.25516,382
224190.55.192.0/18190.55.192.1 to 190.55.255.254190.55.255.25516,382
225190.56.0.0/18190.56.0.1 to 190.56.63.254190.56.63.25516,382
226190.56.64.0/18190.56.64.1 to 190.56.127.254190.56.127.25516,382
227190.56.128.0/18190.56.128.1 to 190.56.191.254190.56.191.25516,382
228190.56.192.0/18190.56.192.1 to 190.56.255.254190.56.255.25516,382
229190.57.0.0/18190.57.0.1 to 190.57.63.254190.57.63.25516,382
230190.57.64.0/18190.57.64.1 to 190.57.127.254190.57.127.25516,382
231190.57.128.0/18190.57.128.1 to 190.57.191.254190.57.191.25516,382
232190.57.192.0/18190.57.192.1 to 190.57.255.254190.57.255.25516,382
233190.58.0.0/18190.58.0.1 to 190.58.63.254190.58.63.25516,382
234190.58.64.0/18190.58.64.1 to 190.58.127.254190.58.127.25516,382
235190.58.128.0/18190.58.128.1 to 190.58.191.254190.58.191.25516,382
236190.58.192.0/18190.58.192.1 to 190.58.255.254190.58.255.25516,382
237190.59.0.0/18190.59.0.1 to 190.59.63.254190.59.63.25516,382
238190.59.64.0/18190.59.64.1 to 190.59.127.254190.59.127.25516,382
239190.59.128.0/18190.59.128.1 to 190.59.191.254190.59.191.25516,382
240190.59.192.0/18190.59.192.1 to 190.59.255.254190.59.255.25516,382
241190.60.0.0/18190.60.0.1 to 190.60.63.254190.60.63.25516,382
242190.60.64.0/18190.60.64.1 to 190.60.127.254190.60.127.25516,382
243190.60.128.0/18190.60.128.1 to 190.60.191.254190.60.191.25516,382
244190.60.192.0/18190.60.192.1 to 190.60.255.254190.60.255.25516,382
245190.61.0.0/18190.61.0.1 to 190.61.63.254190.61.63.25516,382
246190.61.64.0/18190.61.64.1 to 190.61.127.254190.61.127.25516,382
247190.61.128.0/18190.61.128.1 to 190.61.191.254190.61.191.25516,382
248190.61.192.0/18190.61.192.1 to 190.61.255.254190.61.255.25516,382
249190.62.0.0/18190.62.0.1 to 190.62.63.254190.62.63.25516,382
250190.62.64.0/18190.62.64.1 to 190.62.127.254190.62.127.25516,382
251190.62.128.0/18190.62.128.1 to 190.62.191.254190.62.191.25516,382
252190.62.192.0/18190.62.192.1 to 190.62.255.254190.62.255.25516,382
253190.63.0.0/18190.63.0.1 to 190.63.63.254190.63.63.25516,382
254190.63.64.0/18190.63.64.1 to 190.63.127.254190.63.127.25516,382
255190.63.128.0/18190.63.128.1 to 190.63.191.254190.63.191.25516,382
256190.63.192.0/18190.63.192.1 to 190.63.255.254190.63.255.25516,382

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.