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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.

Network182.0.0.0/10
Usable hosts4,194,302
Subnet mask255.192.0.0
Addresses4,194,304
Network address
182.0.0.0
Broadcast address
182.63.255.255
First usable
182.0.0.1
Last usable
182.63.255.254
Usable hosts
4,194,302 (4,194,304 less the network and broadcast addresses)
Subnet mask
255.192.0.0
Wildcard mask
0.63.255.255 (Cisco ACLs, OSPF)
Prefix length
/10
Type
Public public
Old class
B (default /16)
As numbers
Hex B6000000 · Integer 3053453312 to 3057647615
Reverse DNS zones
0.182.in-addr.arpa
1.182.in-addr.arpa
2.182.in-addr.arpa
3.182.in-addr.arpa
4.182.in-addr.arpa
5.182.in-addr.arpa
6.182.in-addr.arpa
7.182.in-addr.arpa
8.182.in-addr.arpa
9.182.in-addr.arpa
10.182.in-addr.arpa
11.182.in-addr.arpa
12.182.in-addr.arpa
13.182.in-addr.arpa
14.182.in-addr.arpa
15.182.in-addr.arpa
and 48 more
/10 is not on a 8-bit boundary, so it takes 64 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address10110110.00000000.00000000.00000000182.0.0.0
Subnet mask11111111.11000000.00000000.00000000255.192.0.0
Network10110110.00000000.00000000.00000000182.0.0.0
Broadcast10110110.00111111.11111111.11111111182.63.255.255
Split into smaller subnets/20
/11 (2)/12 (4)/13 (8)/14 (16)/15 (32)/16 (64)/17 (128)/18 (256)/19 (512)/20 (1,024)/21 (2,048)/22 (4,096)

182.0.0.0/10 makes 1,024 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1182.0.0.0/20182.0.0.1 to 182.0.15.254182.0.15.2554,094
2182.0.16.0/20182.0.16.1 to 182.0.31.254182.0.31.2554,094
3182.0.32.0/20182.0.32.1 to 182.0.47.254182.0.47.2554,094
4182.0.48.0/20182.0.48.1 to 182.0.63.254182.0.63.2554,094
5182.0.64.0/20182.0.64.1 to 182.0.79.254182.0.79.2554,094
6182.0.80.0/20182.0.80.1 to 182.0.95.254182.0.95.2554,094
7182.0.96.0/20182.0.96.1 to 182.0.111.254182.0.111.2554,094
8182.0.112.0/20182.0.112.1 to 182.0.127.254182.0.127.2554,094
9182.0.128.0/20182.0.128.1 to 182.0.143.254182.0.143.2554,094
10182.0.144.0/20182.0.144.1 to 182.0.159.254182.0.159.2554,094
11182.0.160.0/20182.0.160.1 to 182.0.175.254182.0.175.2554,094
12182.0.176.0/20182.0.176.1 to 182.0.191.254182.0.191.2554,094
13182.0.192.0/20182.0.192.1 to 182.0.207.254182.0.207.2554,094
14182.0.208.0/20182.0.208.1 to 182.0.223.254182.0.223.2554,094
15182.0.224.0/20182.0.224.1 to 182.0.239.254182.0.239.2554,094
16182.0.240.0/20182.0.240.1 to 182.0.255.254182.0.255.2554,094
17182.1.0.0/20182.1.0.1 to 182.1.15.254182.1.15.2554,094
18182.1.16.0/20182.1.16.1 to 182.1.31.254182.1.31.2554,094
19182.1.32.0/20182.1.32.1 to 182.1.47.254182.1.47.2554,094
20182.1.48.0/20182.1.48.1 to 182.1.63.254182.1.63.2554,094
21182.1.64.0/20182.1.64.1 to 182.1.79.254182.1.79.2554,094
22182.1.80.0/20182.1.80.1 to 182.1.95.254182.1.95.2554,094
23182.1.96.0/20182.1.96.1 to 182.1.111.254182.1.111.2554,094
24182.1.112.0/20182.1.112.1 to 182.1.127.254182.1.127.2554,094
25182.1.128.0/20182.1.128.1 to 182.1.143.254182.1.143.2554,094
26182.1.144.0/20182.1.144.1 to 182.1.159.254182.1.159.2554,094
27182.1.160.0/20182.1.160.1 to 182.1.175.254182.1.175.2554,094
28182.1.176.0/20182.1.176.1 to 182.1.191.254182.1.191.2554,094
29182.1.192.0/20182.1.192.1 to 182.1.207.254182.1.207.2554,094
30182.1.208.0/20182.1.208.1 to 182.1.223.254182.1.223.2554,094
31182.1.224.0/20182.1.224.1 to 182.1.239.254182.1.239.2554,094
32182.1.240.0/20182.1.240.1 to 182.1.255.254182.1.255.2554,094
33182.2.0.0/20182.2.0.1 to 182.2.15.254182.2.15.2554,094
34182.2.16.0/20182.2.16.1 to 182.2.31.254182.2.31.2554,094
35182.2.32.0/20182.2.32.1 to 182.2.47.254182.2.47.2554,094
36182.2.48.0/20182.2.48.1 to 182.2.63.254182.2.63.2554,094
37182.2.64.0/20182.2.64.1 to 182.2.79.254182.2.79.2554,094
38182.2.80.0/20182.2.80.1 to 182.2.95.254182.2.95.2554,094
39182.2.96.0/20182.2.96.1 to 182.2.111.254182.2.111.2554,094
40182.2.112.0/20182.2.112.1 to 182.2.127.254182.2.127.2554,094
41182.2.128.0/20182.2.128.1 to 182.2.143.254182.2.143.2554,094
42182.2.144.0/20182.2.144.1 to 182.2.159.254182.2.159.2554,094
43182.2.160.0/20182.2.160.1 to 182.2.175.254182.2.175.2554,094
44182.2.176.0/20182.2.176.1 to 182.2.191.254182.2.191.2554,094
45182.2.192.0/20182.2.192.1 to 182.2.207.254182.2.207.2554,094
46182.2.208.0/20182.2.208.1 to 182.2.223.254182.2.223.2554,094
47182.2.224.0/20182.2.224.1 to 182.2.239.254182.2.239.2554,094
48182.2.240.0/20182.2.240.1 to 182.2.255.254182.2.255.2554,094
49182.3.0.0/20182.3.0.1 to 182.3.15.254182.3.15.2554,094
50182.3.16.0/20182.3.16.1 to 182.3.31.254182.3.31.2554,094
51182.3.32.0/20182.3.32.1 to 182.3.47.254182.3.47.2554,094
52182.3.48.0/20182.3.48.1 to 182.3.63.254182.3.63.2554,094
53182.3.64.0/20182.3.64.1 to 182.3.79.254182.3.79.2554,094
54182.3.80.0/20182.3.80.1 to 182.3.95.254182.3.95.2554,094
55182.3.96.0/20182.3.96.1 to 182.3.111.254182.3.111.2554,094
56182.3.112.0/20182.3.112.1 to 182.3.127.254182.3.127.2554,094
57182.3.128.0/20182.3.128.1 to 182.3.143.254182.3.143.2554,094
58182.3.144.0/20182.3.144.1 to 182.3.159.254182.3.159.2554,094
59182.3.160.0/20182.3.160.1 to 182.3.175.254182.3.175.2554,094
60182.3.176.0/20182.3.176.1 to 182.3.191.254182.3.191.2554,094
61182.3.192.0/20182.3.192.1 to 182.3.207.254182.3.207.2554,094
62182.3.208.0/20182.3.208.1 to 182.3.223.254182.3.223.2554,094
63182.3.224.0/20182.3.224.1 to 182.3.239.254182.3.239.2554,094
64182.3.240.0/20182.3.240.1 to 182.3.255.254182.3.255.2554,094
65182.4.0.0/20182.4.0.1 to 182.4.15.254182.4.15.2554,094
66182.4.16.0/20182.4.16.1 to 182.4.31.254182.4.31.2554,094
67182.4.32.0/20182.4.32.1 to 182.4.47.254182.4.47.2554,094
68182.4.48.0/20182.4.48.1 to 182.4.63.254182.4.63.2554,094
69182.4.64.0/20182.4.64.1 to 182.4.79.254182.4.79.2554,094
70182.4.80.0/20182.4.80.1 to 182.4.95.254182.4.95.2554,094
71182.4.96.0/20182.4.96.1 to 182.4.111.254182.4.111.2554,094
72182.4.112.0/20182.4.112.1 to 182.4.127.254182.4.127.2554,094
73182.4.128.0/20182.4.128.1 to 182.4.143.254182.4.143.2554,094
74182.4.144.0/20182.4.144.1 to 182.4.159.254182.4.159.2554,094
75182.4.160.0/20182.4.160.1 to 182.4.175.254182.4.175.2554,094
76182.4.176.0/20182.4.176.1 to 182.4.191.254182.4.191.2554,094
77182.4.192.0/20182.4.192.1 to 182.4.207.254182.4.207.2554,094
78182.4.208.0/20182.4.208.1 to 182.4.223.254182.4.223.2554,094
79182.4.224.0/20182.4.224.1 to 182.4.239.254182.4.239.2554,094
80182.4.240.0/20182.4.240.1 to 182.4.255.254182.4.255.2554,094
81182.5.0.0/20182.5.0.1 to 182.5.15.254182.5.15.2554,094
82182.5.16.0/20182.5.16.1 to 182.5.31.254182.5.31.2554,094
83182.5.32.0/20182.5.32.1 to 182.5.47.254182.5.47.2554,094
84182.5.48.0/20182.5.48.1 to 182.5.63.254182.5.63.2554,094
85182.5.64.0/20182.5.64.1 to 182.5.79.254182.5.79.2554,094
86182.5.80.0/20182.5.80.1 to 182.5.95.254182.5.95.2554,094
87182.5.96.0/20182.5.96.1 to 182.5.111.254182.5.111.2554,094
88182.5.112.0/20182.5.112.1 to 182.5.127.254182.5.127.2554,094
89182.5.128.0/20182.5.128.1 to 182.5.143.254182.5.143.2554,094
90182.5.144.0/20182.5.144.1 to 182.5.159.254182.5.159.2554,094
91182.5.160.0/20182.5.160.1 to 182.5.175.254182.5.175.2554,094
92182.5.176.0/20182.5.176.1 to 182.5.191.254182.5.191.2554,094
93182.5.192.0/20182.5.192.1 to 182.5.207.254182.5.207.2554,094
94182.5.208.0/20182.5.208.1 to 182.5.223.254182.5.223.2554,094
95182.5.224.0/20182.5.224.1 to 182.5.239.254182.5.239.2554,094
96182.5.240.0/20182.5.240.1 to 182.5.255.254182.5.255.2554,094
97182.6.0.0/20182.6.0.1 to 182.6.15.254182.6.15.2554,094
98182.6.16.0/20182.6.16.1 to 182.6.31.254182.6.31.2554,094
99182.6.32.0/20182.6.32.1 to 182.6.47.254182.6.47.2554,094
100182.6.48.0/20182.6.48.1 to 182.6.63.254182.6.63.2554,094
101182.6.64.0/20182.6.64.1 to 182.6.79.254182.6.79.2554,094
102182.6.80.0/20182.6.80.1 to 182.6.95.254182.6.95.2554,094
103182.6.96.0/20182.6.96.1 to 182.6.111.254182.6.111.2554,094
104182.6.112.0/20182.6.112.1 to 182.6.127.254182.6.127.2554,094
105182.6.128.0/20182.6.128.1 to 182.6.143.254182.6.143.2554,094
106182.6.144.0/20182.6.144.1 to 182.6.159.254182.6.159.2554,094
107182.6.160.0/20182.6.160.1 to 182.6.175.254182.6.175.2554,094
108182.6.176.0/20182.6.176.1 to 182.6.191.254182.6.191.2554,094
109182.6.192.0/20182.6.192.1 to 182.6.207.254182.6.207.2554,094
110182.6.208.0/20182.6.208.1 to 182.6.223.254182.6.223.2554,094
111182.6.224.0/20182.6.224.1 to 182.6.239.254182.6.239.2554,094
112182.6.240.0/20182.6.240.1 to 182.6.255.254182.6.255.2554,094
113182.7.0.0/20182.7.0.1 to 182.7.15.254182.7.15.2554,094
114182.7.16.0/20182.7.16.1 to 182.7.31.254182.7.31.2554,094
115182.7.32.0/20182.7.32.1 to 182.7.47.254182.7.47.2554,094
116182.7.48.0/20182.7.48.1 to 182.7.63.254182.7.63.2554,094
117182.7.64.0/20182.7.64.1 to 182.7.79.254182.7.79.2554,094
118182.7.80.0/20182.7.80.1 to 182.7.95.254182.7.95.2554,094
119182.7.96.0/20182.7.96.1 to 182.7.111.254182.7.111.2554,094
120182.7.112.0/20182.7.112.1 to 182.7.127.254182.7.127.2554,094
121182.7.128.0/20182.7.128.1 to 182.7.143.254182.7.143.2554,094
122182.7.144.0/20182.7.144.1 to 182.7.159.254182.7.159.2554,094
123182.7.160.0/20182.7.160.1 to 182.7.175.254182.7.175.2554,094
124182.7.176.0/20182.7.176.1 to 182.7.191.254182.7.191.2554,094
125182.7.192.0/20182.7.192.1 to 182.7.207.254182.7.207.2554,094
126182.7.208.0/20182.7.208.1 to 182.7.223.254182.7.223.2554,094
127182.7.224.0/20182.7.224.1 to 182.7.239.254182.7.239.2554,094
128182.7.240.0/20182.7.240.1 to 182.7.255.254182.7.255.2554,094
129182.8.0.0/20182.8.0.1 to 182.8.15.254182.8.15.2554,094
130182.8.16.0/20182.8.16.1 to 182.8.31.254182.8.31.2554,094
131182.8.32.0/20182.8.32.1 to 182.8.47.254182.8.47.2554,094
132182.8.48.0/20182.8.48.1 to 182.8.63.254182.8.63.2554,094
133182.8.64.0/20182.8.64.1 to 182.8.79.254182.8.79.2554,094
134182.8.80.0/20182.8.80.1 to 182.8.95.254182.8.95.2554,094
135182.8.96.0/20182.8.96.1 to 182.8.111.254182.8.111.2554,094
136182.8.112.0/20182.8.112.1 to 182.8.127.254182.8.127.2554,094
137182.8.128.0/20182.8.128.1 to 182.8.143.254182.8.143.2554,094
138182.8.144.0/20182.8.144.1 to 182.8.159.254182.8.159.2554,094
139182.8.160.0/20182.8.160.1 to 182.8.175.254182.8.175.2554,094
140182.8.176.0/20182.8.176.1 to 182.8.191.254182.8.191.2554,094
141182.8.192.0/20182.8.192.1 to 182.8.207.254182.8.207.2554,094
142182.8.208.0/20182.8.208.1 to 182.8.223.254182.8.223.2554,094
143182.8.224.0/20182.8.224.1 to 182.8.239.254182.8.239.2554,094
144182.8.240.0/20182.8.240.1 to 182.8.255.254182.8.255.2554,094
145182.9.0.0/20182.9.0.1 to 182.9.15.254182.9.15.2554,094
146182.9.16.0/20182.9.16.1 to 182.9.31.254182.9.31.2554,094
147182.9.32.0/20182.9.32.1 to 182.9.47.254182.9.47.2554,094
148182.9.48.0/20182.9.48.1 to 182.9.63.254182.9.63.2554,094
149182.9.64.0/20182.9.64.1 to 182.9.79.254182.9.79.2554,094
150182.9.80.0/20182.9.80.1 to 182.9.95.254182.9.95.2554,094
151182.9.96.0/20182.9.96.1 to 182.9.111.254182.9.111.2554,094
152182.9.112.0/20182.9.112.1 to 182.9.127.254182.9.127.2554,094
153182.9.128.0/20182.9.128.1 to 182.9.143.254182.9.143.2554,094
154182.9.144.0/20182.9.144.1 to 182.9.159.254182.9.159.2554,094
155182.9.160.0/20182.9.160.1 to 182.9.175.254182.9.175.2554,094
156182.9.176.0/20182.9.176.1 to 182.9.191.254182.9.191.2554,094
157182.9.192.0/20182.9.192.1 to 182.9.207.254182.9.207.2554,094
158182.9.208.0/20182.9.208.1 to 182.9.223.254182.9.223.2554,094
159182.9.224.0/20182.9.224.1 to 182.9.239.254182.9.239.2554,094
160182.9.240.0/20182.9.240.1 to 182.9.255.254182.9.255.2554,094
161182.10.0.0/20182.10.0.1 to 182.10.15.254182.10.15.2554,094
162182.10.16.0/20182.10.16.1 to 182.10.31.254182.10.31.2554,094
163182.10.32.0/20182.10.32.1 to 182.10.47.254182.10.47.2554,094
164182.10.48.0/20182.10.48.1 to 182.10.63.254182.10.63.2554,094
165182.10.64.0/20182.10.64.1 to 182.10.79.254182.10.79.2554,094
166182.10.80.0/20182.10.80.1 to 182.10.95.254182.10.95.2554,094
167182.10.96.0/20182.10.96.1 to 182.10.111.254182.10.111.2554,094
168182.10.112.0/20182.10.112.1 to 182.10.127.254182.10.127.2554,094
169182.10.128.0/20182.10.128.1 to 182.10.143.254182.10.143.2554,094
170182.10.144.0/20182.10.144.1 to 182.10.159.254182.10.159.2554,094
171182.10.160.0/20182.10.160.1 to 182.10.175.254182.10.175.2554,094
172182.10.176.0/20182.10.176.1 to 182.10.191.254182.10.191.2554,094
173182.10.192.0/20182.10.192.1 to 182.10.207.254182.10.207.2554,094
174182.10.208.0/20182.10.208.1 to 182.10.223.254182.10.223.2554,094
175182.10.224.0/20182.10.224.1 to 182.10.239.254182.10.239.2554,094
176182.10.240.0/20182.10.240.1 to 182.10.255.254182.10.255.2554,094
177182.11.0.0/20182.11.0.1 to 182.11.15.254182.11.15.2554,094
178182.11.16.0/20182.11.16.1 to 182.11.31.254182.11.31.2554,094
179182.11.32.0/20182.11.32.1 to 182.11.47.254182.11.47.2554,094
180182.11.48.0/20182.11.48.1 to 182.11.63.254182.11.63.2554,094
181182.11.64.0/20182.11.64.1 to 182.11.79.254182.11.79.2554,094
182182.11.80.0/20182.11.80.1 to 182.11.95.254182.11.95.2554,094
183182.11.96.0/20182.11.96.1 to 182.11.111.254182.11.111.2554,094
184182.11.112.0/20182.11.112.1 to 182.11.127.254182.11.127.2554,094
185182.11.128.0/20182.11.128.1 to 182.11.143.254182.11.143.2554,094
186182.11.144.0/20182.11.144.1 to 182.11.159.254182.11.159.2554,094
187182.11.160.0/20182.11.160.1 to 182.11.175.254182.11.175.2554,094
188182.11.176.0/20182.11.176.1 to 182.11.191.254182.11.191.2554,094
189182.11.192.0/20182.11.192.1 to 182.11.207.254182.11.207.2554,094
190182.11.208.0/20182.11.208.1 to 182.11.223.254182.11.223.2554,094
191182.11.224.0/20182.11.224.1 to 182.11.239.254182.11.239.2554,094
192182.11.240.0/20182.11.240.1 to 182.11.255.254182.11.255.2554,094
193182.12.0.0/20182.12.0.1 to 182.12.15.254182.12.15.2554,094
194182.12.16.0/20182.12.16.1 to 182.12.31.254182.12.31.2554,094
195182.12.32.0/20182.12.32.1 to 182.12.47.254182.12.47.2554,094
196182.12.48.0/20182.12.48.1 to 182.12.63.254182.12.63.2554,094
197182.12.64.0/20182.12.64.1 to 182.12.79.254182.12.79.2554,094
198182.12.80.0/20182.12.80.1 to 182.12.95.254182.12.95.2554,094
199182.12.96.0/20182.12.96.1 to 182.12.111.254182.12.111.2554,094
200182.12.112.0/20182.12.112.1 to 182.12.127.254182.12.127.2554,094
201182.12.128.0/20182.12.128.1 to 182.12.143.254182.12.143.2554,094
202182.12.144.0/20182.12.144.1 to 182.12.159.254182.12.159.2554,094
203182.12.160.0/20182.12.160.1 to 182.12.175.254182.12.175.2554,094
204182.12.176.0/20182.12.176.1 to 182.12.191.254182.12.191.2554,094
205182.12.192.0/20182.12.192.1 to 182.12.207.254182.12.207.2554,094
206182.12.208.0/20182.12.208.1 to 182.12.223.254182.12.223.2554,094
207182.12.224.0/20182.12.224.1 to 182.12.239.254182.12.239.2554,094
208182.12.240.0/20182.12.240.1 to 182.12.255.254182.12.255.2554,094
209182.13.0.0/20182.13.0.1 to 182.13.15.254182.13.15.2554,094
210182.13.16.0/20182.13.16.1 to 182.13.31.254182.13.31.2554,094
211182.13.32.0/20182.13.32.1 to 182.13.47.254182.13.47.2554,094
212182.13.48.0/20182.13.48.1 to 182.13.63.254182.13.63.2554,094
213182.13.64.0/20182.13.64.1 to 182.13.79.254182.13.79.2554,094
214182.13.80.0/20182.13.80.1 to 182.13.95.254182.13.95.2554,094
215182.13.96.0/20182.13.96.1 to 182.13.111.254182.13.111.2554,094
216182.13.112.0/20182.13.112.1 to 182.13.127.254182.13.127.2554,094
217182.13.128.0/20182.13.128.1 to 182.13.143.254182.13.143.2554,094
218182.13.144.0/20182.13.144.1 to 182.13.159.254182.13.159.2554,094
219182.13.160.0/20182.13.160.1 to 182.13.175.254182.13.175.2554,094
220182.13.176.0/20182.13.176.1 to 182.13.191.254182.13.191.2554,094
221182.13.192.0/20182.13.192.1 to 182.13.207.254182.13.207.2554,094
222182.13.208.0/20182.13.208.1 to 182.13.223.254182.13.223.2554,094
223182.13.224.0/20182.13.224.1 to 182.13.239.254182.13.239.2554,094
224182.13.240.0/20182.13.240.1 to 182.13.255.254182.13.255.2554,094
225182.14.0.0/20182.14.0.1 to 182.14.15.254182.14.15.2554,094
226182.14.16.0/20182.14.16.1 to 182.14.31.254182.14.31.2554,094
227182.14.32.0/20182.14.32.1 to 182.14.47.254182.14.47.2554,094
228182.14.48.0/20182.14.48.1 to 182.14.63.254182.14.63.2554,094
229182.14.64.0/20182.14.64.1 to 182.14.79.254182.14.79.2554,094
230182.14.80.0/20182.14.80.1 to 182.14.95.254182.14.95.2554,094
231182.14.96.0/20182.14.96.1 to 182.14.111.254182.14.111.2554,094
232182.14.112.0/20182.14.112.1 to 182.14.127.254182.14.127.2554,094
233182.14.128.0/20182.14.128.1 to 182.14.143.254182.14.143.2554,094
234182.14.144.0/20182.14.144.1 to 182.14.159.254182.14.159.2554,094
235182.14.160.0/20182.14.160.1 to 182.14.175.254182.14.175.2554,094
236182.14.176.0/20182.14.176.1 to 182.14.191.254182.14.191.2554,094
237182.14.192.0/20182.14.192.1 to 182.14.207.254182.14.207.2554,094
238182.14.208.0/20182.14.208.1 to 182.14.223.254182.14.223.2554,094
239182.14.224.0/20182.14.224.1 to 182.14.239.254182.14.239.2554,094
240182.14.240.0/20182.14.240.1 to 182.14.255.254182.14.255.2554,094
241182.15.0.0/20182.15.0.1 to 182.15.15.254182.15.15.2554,094
242182.15.16.0/20182.15.16.1 to 182.15.31.254182.15.31.2554,094
243182.15.32.0/20182.15.32.1 to 182.15.47.254182.15.47.2554,094
244182.15.48.0/20182.15.48.1 to 182.15.63.254182.15.63.2554,094
245182.15.64.0/20182.15.64.1 to 182.15.79.254182.15.79.2554,094
246182.15.80.0/20182.15.80.1 to 182.15.95.254182.15.95.2554,094
247182.15.96.0/20182.15.96.1 to 182.15.111.254182.15.111.2554,094
248182.15.112.0/20182.15.112.1 to 182.15.127.254182.15.127.2554,094
249182.15.128.0/20182.15.128.1 to 182.15.143.254182.15.143.2554,094
250182.15.144.0/20182.15.144.1 to 182.15.159.254182.15.159.2554,094
251182.15.160.0/20182.15.160.1 to 182.15.175.254182.15.175.2554,094
252182.15.176.0/20182.15.176.1 to 182.15.191.254182.15.191.2554,094
253182.15.192.0/20182.15.192.1 to 182.15.207.254182.15.207.2554,094
254182.15.208.0/20182.15.208.1 to 182.15.223.254182.15.223.2554,094
255182.15.224.0/20182.15.224.1 to 182.15.239.254182.15.239.2554,094
256182.15.240.0/20182.15.240.1 to 182.15.255.254182.15.255.2554,094

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.