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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.

Network250.96.0.0/11
Usable hosts2,097,150
Subnet mask255.224.0.0
Addresses2,097,152
Network address
250.96.0.0
Broadcast address
250.127.255.255
First usable
250.96.0.1
Last usable
250.127.255.254
Usable hosts
2,097,150 (2,097,152 less the network and broadcast addresses)
Subnet mask
255.224.0.0
Wildcard mask
0.31.255.255 (Cisco ACLs, OSPF)
Prefix length
/11
Type
Reserved 240.0.0.0/4
Future use; not usable on most systems
Old class
E (reserved)
As numbers
Hex FA600000 · Integer 4200595456 to 4202692607
Reverse DNS zones
96.250.in-addr.arpa
97.250.in-addr.arpa
98.250.in-addr.arpa
99.250.in-addr.arpa
100.250.in-addr.arpa
101.250.in-addr.arpa
102.250.in-addr.arpa
103.250.in-addr.arpa
104.250.in-addr.arpa
105.250.in-addr.arpa
106.250.in-addr.arpa
107.250.in-addr.arpa
108.250.in-addr.arpa
109.250.in-addr.arpa
110.250.in-addr.arpa
111.250.in-addr.arpa
and 16 more
/11 is not on a 8-bit boundary, so it takes 32 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11111010.01100000.00000000.00000000250.96.0.0
Subnet mask11111111.11100000.00000000.00000000255.224.0.0
Network11111010.01100000.00000000.00000000250.96.0.0
Broadcast11111010.01111111.11111111.11111111250.127.255.255
Split into smaller subnets/20
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/17 (64)/18 (128)/19 (256)/20 (512)/21 (1,024)/22 (2,048)/23 (4,096)

250.96.0.0/11 makes 512 subnets of /20; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1250.96.0.0/20250.96.0.1 to 250.96.15.254250.96.15.2554,094
2250.96.16.0/20250.96.16.1 to 250.96.31.254250.96.31.2554,094
3250.96.32.0/20250.96.32.1 to 250.96.47.254250.96.47.2554,094
4250.96.48.0/20250.96.48.1 to 250.96.63.254250.96.63.2554,094
5250.96.64.0/20250.96.64.1 to 250.96.79.254250.96.79.2554,094
6250.96.80.0/20250.96.80.1 to 250.96.95.254250.96.95.2554,094
7250.96.96.0/20250.96.96.1 to 250.96.111.254250.96.111.2554,094
8250.96.112.0/20250.96.112.1 to 250.96.127.254250.96.127.2554,094
9250.96.128.0/20250.96.128.1 to 250.96.143.254250.96.143.2554,094
10250.96.144.0/20250.96.144.1 to 250.96.159.254250.96.159.2554,094
11250.96.160.0/20250.96.160.1 to 250.96.175.254250.96.175.2554,094
12250.96.176.0/20250.96.176.1 to 250.96.191.254250.96.191.2554,094
13250.96.192.0/20250.96.192.1 to 250.96.207.254250.96.207.2554,094
14250.96.208.0/20250.96.208.1 to 250.96.223.254250.96.223.2554,094
15250.96.224.0/20250.96.224.1 to 250.96.239.254250.96.239.2554,094
16250.96.240.0/20250.96.240.1 to 250.96.255.254250.96.255.2554,094
17250.97.0.0/20250.97.0.1 to 250.97.15.254250.97.15.2554,094
18250.97.16.0/20250.97.16.1 to 250.97.31.254250.97.31.2554,094
19250.97.32.0/20250.97.32.1 to 250.97.47.254250.97.47.2554,094
20250.97.48.0/20250.97.48.1 to 250.97.63.254250.97.63.2554,094
21250.97.64.0/20250.97.64.1 to 250.97.79.254250.97.79.2554,094
22250.97.80.0/20250.97.80.1 to 250.97.95.254250.97.95.2554,094
23250.97.96.0/20250.97.96.1 to 250.97.111.254250.97.111.2554,094
24250.97.112.0/20250.97.112.1 to 250.97.127.254250.97.127.2554,094
25250.97.128.0/20250.97.128.1 to 250.97.143.254250.97.143.2554,094
26250.97.144.0/20250.97.144.1 to 250.97.159.254250.97.159.2554,094
27250.97.160.0/20250.97.160.1 to 250.97.175.254250.97.175.2554,094
28250.97.176.0/20250.97.176.1 to 250.97.191.254250.97.191.2554,094
29250.97.192.0/20250.97.192.1 to 250.97.207.254250.97.207.2554,094
30250.97.208.0/20250.97.208.1 to 250.97.223.254250.97.223.2554,094
31250.97.224.0/20250.97.224.1 to 250.97.239.254250.97.239.2554,094
32250.97.240.0/20250.97.240.1 to 250.97.255.254250.97.255.2554,094
33250.98.0.0/20250.98.0.1 to 250.98.15.254250.98.15.2554,094
34250.98.16.0/20250.98.16.1 to 250.98.31.254250.98.31.2554,094
35250.98.32.0/20250.98.32.1 to 250.98.47.254250.98.47.2554,094
36250.98.48.0/20250.98.48.1 to 250.98.63.254250.98.63.2554,094
37250.98.64.0/20250.98.64.1 to 250.98.79.254250.98.79.2554,094
38250.98.80.0/20250.98.80.1 to 250.98.95.254250.98.95.2554,094
39250.98.96.0/20250.98.96.1 to 250.98.111.254250.98.111.2554,094
40250.98.112.0/20250.98.112.1 to 250.98.127.254250.98.127.2554,094
41250.98.128.0/20250.98.128.1 to 250.98.143.254250.98.143.2554,094
42250.98.144.0/20250.98.144.1 to 250.98.159.254250.98.159.2554,094
43250.98.160.0/20250.98.160.1 to 250.98.175.254250.98.175.2554,094
44250.98.176.0/20250.98.176.1 to 250.98.191.254250.98.191.2554,094
45250.98.192.0/20250.98.192.1 to 250.98.207.254250.98.207.2554,094
46250.98.208.0/20250.98.208.1 to 250.98.223.254250.98.223.2554,094
47250.98.224.0/20250.98.224.1 to 250.98.239.254250.98.239.2554,094
48250.98.240.0/20250.98.240.1 to 250.98.255.254250.98.255.2554,094
49250.99.0.0/20250.99.0.1 to 250.99.15.254250.99.15.2554,094
50250.99.16.0/20250.99.16.1 to 250.99.31.254250.99.31.2554,094
51250.99.32.0/20250.99.32.1 to 250.99.47.254250.99.47.2554,094
52250.99.48.0/20250.99.48.1 to 250.99.63.254250.99.63.2554,094
53250.99.64.0/20250.99.64.1 to 250.99.79.254250.99.79.2554,094
54250.99.80.0/20250.99.80.1 to 250.99.95.254250.99.95.2554,094
55250.99.96.0/20250.99.96.1 to 250.99.111.254250.99.111.2554,094
56250.99.112.0/20250.99.112.1 to 250.99.127.254250.99.127.2554,094
57250.99.128.0/20250.99.128.1 to 250.99.143.254250.99.143.2554,094
58250.99.144.0/20250.99.144.1 to 250.99.159.254250.99.159.2554,094
59250.99.160.0/20250.99.160.1 to 250.99.175.254250.99.175.2554,094
60250.99.176.0/20250.99.176.1 to 250.99.191.254250.99.191.2554,094
61250.99.192.0/20250.99.192.1 to 250.99.207.254250.99.207.2554,094
62250.99.208.0/20250.99.208.1 to 250.99.223.254250.99.223.2554,094
63250.99.224.0/20250.99.224.1 to 250.99.239.254250.99.239.2554,094
64250.99.240.0/20250.99.240.1 to 250.99.255.254250.99.255.2554,094
65250.100.0.0/20250.100.0.1 to 250.100.15.254250.100.15.2554,094
66250.100.16.0/20250.100.16.1 to 250.100.31.254250.100.31.2554,094
67250.100.32.0/20250.100.32.1 to 250.100.47.254250.100.47.2554,094
68250.100.48.0/20250.100.48.1 to 250.100.63.254250.100.63.2554,094
69250.100.64.0/20250.100.64.1 to 250.100.79.254250.100.79.2554,094
70250.100.80.0/20250.100.80.1 to 250.100.95.254250.100.95.2554,094
71250.100.96.0/20250.100.96.1 to 250.100.111.254250.100.111.2554,094
72250.100.112.0/20250.100.112.1 to 250.100.127.254250.100.127.2554,094
73250.100.128.0/20250.100.128.1 to 250.100.143.254250.100.143.2554,094
74250.100.144.0/20250.100.144.1 to 250.100.159.254250.100.159.2554,094
75250.100.160.0/20250.100.160.1 to 250.100.175.254250.100.175.2554,094
76250.100.176.0/20250.100.176.1 to 250.100.191.254250.100.191.2554,094
77250.100.192.0/20250.100.192.1 to 250.100.207.254250.100.207.2554,094
78250.100.208.0/20250.100.208.1 to 250.100.223.254250.100.223.2554,094
79250.100.224.0/20250.100.224.1 to 250.100.239.254250.100.239.2554,094
80250.100.240.0/20250.100.240.1 to 250.100.255.254250.100.255.2554,094
81250.101.0.0/20250.101.0.1 to 250.101.15.254250.101.15.2554,094
82250.101.16.0/20250.101.16.1 to 250.101.31.254250.101.31.2554,094
83250.101.32.0/20250.101.32.1 to 250.101.47.254250.101.47.2554,094
84250.101.48.0/20250.101.48.1 to 250.101.63.254250.101.63.2554,094
85250.101.64.0/20250.101.64.1 to 250.101.79.254250.101.79.2554,094
86250.101.80.0/20250.101.80.1 to 250.101.95.254250.101.95.2554,094
87250.101.96.0/20250.101.96.1 to 250.101.111.254250.101.111.2554,094
88250.101.112.0/20250.101.112.1 to 250.101.127.254250.101.127.2554,094
89250.101.128.0/20250.101.128.1 to 250.101.143.254250.101.143.2554,094
90250.101.144.0/20250.101.144.1 to 250.101.159.254250.101.159.2554,094
91250.101.160.0/20250.101.160.1 to 250.101.175.254250.101.175.2554,094
92250.101.176.0/20250.101.176.1 to 250.101.191.254250.101.191.2554,094
93250.101.192.0/20250.101.192.1 to 250.101.207.254250.101.207.2554,094
94250.101.208.0/20250.101.208.1 to 250.101.223.254250.101.223.2554,094
95250.101.224.0/20250.101.224.1 to 250.101.239.254250.101.239.2554,094
96250.101.240.0/20250.101.240.1 to 250.101.255.254250.101.255.2554,094
97250.102.0.0/20250.102.0.1 to 250.102.15.254250.102.15.2554,094
98250.102.16.0/20250.102.16.1 to 250.102.31.254250.102.31.2554,094
99250.102.32.0/20250.102.32.1 to 250.102.47.254250.102.47.2554,094
100250.102.48.0/20250.102.48.1 to 250.102.63.254250.102.63.2554,094
101250.102.64.0/20250.102.64.1 to 250.102.79.254250.102.79.2554,094
102250.102.80.0/20250.102.80.1 to 250.102.95.254250.102.95.2554,094
103250.102.96.0/20250.102.96.1 to 250.102.111.254250.102.111.2554,094
104250.102.112.0/20250.102.112.1 to 250.102.127.254250.102.127.2554,094
105250.102.128.0/20250.102.128.1 to 250.102.143.254250.102.143.2554,094
106250.102.144.0/20250.102.144.1 to 250.102.159.254250.102.159.2554,094
107250.102.160.0/20250.102.160.1 to 250.102.175.254250.102.175.2554,094
108250.102.176.0/20250.102.176.1 to 250.102.191.254250.102.191.2554,094
109250.102.192.0/20250.102.192.1 to 250.102.207.254250.102.207.2554,094
110250.102.208.0/20250.102.208.1 to 250.102.223.254250.102.223.2554,094
111250.102.224.0/20250.102.224.1 to 250.102.239.254250.102.239.2554,094
112250.102.240.0/20250.102.240.1 to 250.102.255.254250.102.255.2554,094
113250.103.0.0/20250.103.0.1 to 250.103.15.254250.103.15.2554,094
114250.103.16.0/20250.103.16.1 to 250.103.31.254250.103.31.2554,094
115250.103.32.0/20250.103.32.1 to 250.103.47.254250.103.47.2554,094
116250.103.48.0/20250.103.48.1 to 250.103.63.254250.103.63.2554,094
117250.103.64.0/20250.103.64.1 to 250.103.79.254250.103.79.2554,094
118250.103.80.0/20250.103.80.1 to 250.103.95.254250.103.95.2554,094
119250.103.96.0/20250.103.96.1 to 250.103.111.254250.103.111.2554,094
120250.103.112.0/20250.103.112.1 to 250.103.127.254250.103.127.2554,094
121250.103.128.0/20250.103.128.1 to 250.103.143.254250.103.143.2554,094
122250.103.144.0/20250.103.144.1 to 250.103.159.254250.103.159.2554,094
123250.103.160.0/20250.103.160.1 to 250.103.175.254250.103.175.2554,094
124250.103.176.0/20250.103.176.1 to 250.103.191.254250.103.191.2554,094
125250.103.192.0/20250.103.192.1 to 250.103.207.254250.103.207.2554,094
126250.103.208.0/20250.103.208.1 to 250.103.223.254250.103.223.2554,094
127250.103.224.0/20250.103.224.1 to 250.103.239.254250.103.239.2554,094
128250.103.240.0/20250.103.240.1 to 250.103.255.254250.103.255.2554,094
129250.104.0.0/20250.104.0.1 to 250.104.15.254250.104.15.2554,094
130250.104.16.0/20250.104.16.1 to 250.104.31.254250.104.31.2554,094
131250.104.32.0/20250.104.32.1 to 250.104.47.254250.104.47.2554,094
132250.104.48.0/20250.104.48.1 to 250.104.63.254250.104.63.2554,094
133250.104.64.0/20250.104.64.1 to 250.104.79.254250.104.79.2554,094
134250.104.80.0/20250.104.80.1 to 250.104.95.254250.104.95.2554,094
135250.104.96.0/20250.104.96.1 to 250.104.111.254250.104.111.2554,094
136250.104.112.0/20250.104.112.1 to 250.104.127.254250.104.127.2554,094
137250.104.128.0/20250.104.128.1 to 250.104.143.254250.104.143.2554,094
138250.104.144.0/20250.104.144.1 to 250.104.159.254250.104.159.2554,094
139250.104.160.0/20250.104.160.1 to 250.104.175.254250.104.175.2554,094
140250.104.176.0/20250.104.176.1 to 250.104.191.254250.104.191.2554,094
141250.104.192.0/20250.104.192.1 to 250.104.207.254250.104.207.2554,094
142250.104.208.0/20250.104.208.1 to 250.104.223.254250.104.223.2554,094
143250.104.224.0/20250.104.224.1 to 250.104.239.254250.104.239.2554,094
144250.104.240.0/20250.104.240.1 to 250.104.255.254250.104.255.2554,094
145250.105.0.0/20250.105.0.1 to 250.105.15.254250.105.15.2554,094
146250.105.16.0/20250.105.16.1 to 250.105.31.254250.105.31.2554,094
147250.105.32.0/20250.105.32.1 to 250.105.47.254250.105.47.2554,094
148250.105.48.0/20250.105.48.1 to 250.105.63.254250.105.63.2554,094
149250.105.64.0/20250.105.64.1 to 250.105.79.254250.105.79.2554,094
150250.105.80.0/20250.105.80.1 to 250.105.95.254250.105.95.2554,094
151250.105.96.0/20250.105.96.1 to 250.105.111.254250.105.111.2554,094
152250.105.112.0/20250.105.112.1 to 250.105.127.254250.105.127.2554,094
153250.105.128.0/20250.105.128.1 to 250.105.143.254250.105.143.2554,094
154250.105.144.0/20250.105.144.1 to 250.105.159.254250.105.159.2554,094
155250.105.160.0/20250.105.160.1 to 250.105.175.254250.105.175.2554,094
156250.105.176.0/20250.105.176.1 to 250.105.191.254250.105.191.2554,094
157250.105.192.0/20250.105.192.1 to 250.105.207.254250.105.207.2554,094
158250.105.208.0/20250.105.208.1 to 250.105.223.254250.105.223.2554,094
159250.105.224.0/20250.105.224.1 to 250.105.239.254250.105.239.2554,094
160250.105.240.0/20250.105.240.1 to 250.105.255.254250.105.255.2554,094
161250.106.0.0/20250.106.0.1 to 250.106.15.254250.106.15.2554,094
162250.106.16.0/20250.106.16.1 to 250.106.31.254250.106.31.2554,094
163250.106.32.0/20250.106.32.1 to 250.106.47.254250.106.47.2554,094
164250.106.48.0/20250.106.48.1 to 250.106.63.254250.106.63.2554,094
165250.106.64.0/20250.106.64.1 to 250.106.79.254250.106.79.2554,094
166250.106.80.0/20250.106.80.1 to 250.106.95.254250.106.95.2554,094
167250.106.96.0/20250.106.96.1 to 250.106.111.254250.106.111.2554,094
168250.106.112.0/20250.106.112.1 to 250.106.127.254250.106.127.2554,094
169250.106.128.0/20250.106.128.1 to 250.106.143.254250.106.143.2554,094
170250.106.144.0/20250.106.144.1 to 250.106.159.254250.106.159.2554,094
171250.106.160.0/20250.106.160.1 to 250.106.175.254250.106.175.2554,094
172250.106.176.0/20250.106.176.1 to 250.106.191.254250.106.191.2554,094
173250.106.192.0/20250.106.192.1 to 250.106.207.254250.106.207.2554,094
174250.106.208.0/20250.106.208.1 to 250.106.223.254250.106.223.2554,094
175250.106.224.0/20250.106.224.1 to 250.106.239.254250.106.239.2554,094
176250.106.240.0/20250.106.240.1 to 250.106.255.254250.106.255.2554,094
177250.107.0.0/20250.107.0.1 to 250.107.15.254250.107.15.2554,094
178250.107.16.0/20250.107.16.1 to 250.107.31.254250.107.31.2554,094
179250.107.32.0/20250.107.32.1 to 250.107.47.254250.107.47.2554,094
180250.107.48.0/20250.107.48.1 to 250.107.63.254250.107.63.2554,094
181250.107.64.0/20250.107.64.1 to 250.107.79.254250.107.79.2554,094
182250.107.80.0/20250.107.80.1 to 250.107.95.254250.107.95.2554,094
183250.107.96.0/20250.107.96.1 to 250.107.111.254250.107.111.2554,094
184250.107.112.0/20250.107.112.1 to 250.107.127.254250.107.127.2554,094
185250.107.128.0/20250.107.128.1 to 250.107.143.254250.107.143.2554,094
186250.107.144.0/20250.107.144.1 to 250.107.159.254250.107.159.2554,094
187250.107.160.0/20250.107.160.1 to 250.107.175.254250.107.175.2554,094
188250.107.176.0/20250.107.176.1 to 250.107.191.254250.107.191.2554,094
189250.107.192.0/20250.107.192.1 to 250.107.207.254250.107.207.2554,094
190250.107.208.0/20250.107.208.1 to 250.107.223.254250.107.223.2554,094
191250.107.224.0/20250.107.224.1 to 250.107.239.254250.107.239.2554,094
192250.107.240.0/20250.107.240.1 to 250.107.255.254250.107.255.2554,094
193250.108.0.0/20250.108.0.1 to 250.108.15.254250.108.15.2554,094
194250.108.16.0/20250.108.16.1 to 250.108.31.254250.108.31.2554,094
195250.108.32.0/20250.108.32.1 to 250.108.47.254250.108.47.2554,094
196250.108.48.0/20250.108.48.1 to 250.108.63.254250.108.63.2554,094
197250.108.64.0/20250.108.64.1 to 250.108.79.254250.108.79.2554,094
198250.108.80.0/20250.108.80.1 to 250.108.95.254250.108.95.2554,094
199250.108.96.0/20250.108.96.1 to 250.108.111.254250.108.111.2554,094
200250.108.112.0/20250.108.112.1 to 250.108.127.254250.108.127.2554,094
201250.108.128.0/20250.108.128.1 to 250.108.143.254250.108.143.2554,094
202250.108.144.0/20250.108.144.1 to 250.108.159.254250.108.159.2554,094
203250.108.160.0/20250.108.160.1 to 250.108.175.254250.108.175.2554,094
204250.108.176.0/20250.108.176.1 to 250.108.191.254250.108.191.2554,094
205250.108.192.0/20250.108.192.1 to 250.108.207.254250.108.207.2554,094
206250.108.208.0/20250.108.208.1 to 250.108.223.254250.108.223.2554,094
207250.108.224.0/20250.108.224.1 to 250.108.239.254250.108.239.2554,094
208250.108.240.0/20250.108.240.1 to 250.108.255.254250.108.255.2554,094
209250.109.0.0/20250.109.0.1 to 250.109.15.254250.109.15.2554,094
210250.109.16.0/20250.109.16.1 to 250.109.31.254250.109.31.2554,094
211250.109.32.0/20250.109.32.1 to 250.109.47.254250.109.47.2554,094
212250.109.48.0/20250.109.48.1 to 250.109.63.254250.109.63.2554,094
213250.109.64.0/20250.109.64.1 to 250.109.79.254250.109.79.2554,094
214250.109.80.0/20250.109.80.1 to 250.109.95.254250.109.95.2554,094
215250.109.96.0/20250.109.96.1 to 250.109.111.254250.109.111.2554,094
216250.109.112.0/20250.109.112.1 to 250.109.127.254250.109.127.2554,094
217250.109.128.0/20250.109.128.1 to 250.109.143.254250.109.143.2554,094
218250.109.144.0/20250.109.144.1 to 250.109.159.254250.109.159.2554,094
219250.109.160.0/20250.109.160.1 to 250.109.175.254250.109.175.2554,094
220250.109.176.0/20250.109.176.1 to 250.109.191.254250.109.191.2554,094
221250.109.192.0/20250.109.192.1 to 250.109.207.254250.109.207.2554,094
222250.109.208.0/20250.109.208.1 to 250.109.223.254250.109.223.2554,094
223250.109.224.0/20250.109.224.1 to 250.109.239.254250.109.239.2554,094
224250.109.240.0/20250.109.240.1 to 250.109.255.254250.109.255.2554,094
225250.110.0.0/20250.110.0.1 to 250.110.15.254250.110.15.2554,094
226250.110.16.0/20250.110.16.1 to 250.110.31.254250.110.31.2554,094
227250.110.32.0/20250.110.32.1 to 250.110.47.254250.110.47.2554,094
228250.110.48.0/20250.110.48.1 to 250.110.63.254250.110.63.2554,094
229250.110.64.0/20250.110.64.1 to 250.110.79.254250.110.79.2554,094
230250.110.80.0/20250.110.80.1 to 250.110.95.254250.110.95.2554,094
231250.110.96.0/20250.110.96.1 to 250.110.111.254250.110.111.2554,094
232250.110.112.0/20250.110.112.1 to 250.110.127.254250.110.127.2554,094
233250.110.128.0/20250.110.128.1 to 250.110.143.254250.110.143.2554,094
234250.110.144.0/20250.110.144.1 to 250.110.159.254250.110.159.2554,094
235250.110.160.0/20250.110.160.1 to 250.110.175.254250.110.175.2554,094
236250.110.176.0/20250.110.176.1 to 250.110.191.254250.110.191.2554,094
237250.110.192.0/20250.110.192.1 to 250.110.207.254250.110.207.2554,094
238250.110.208.0/20250.110.208.1 to 250.110.223.254250.110.223.2554,094
239250.110.224.0/20250.110.224.1 to 250.110.239.254250.110.239.2554,094
240250.110.240.0/20250.110.240.1 to 250.110.255.254250.110.255.2554,094
241250.111.0.0/20250.111.0.1 to 250.111.15.254250.111.15.2554,094
242250.111.16.0/20250.111.16.1 to 250.111.31.254250.111.31.2554,094
243250.111.32.0/20250.111.32.1 to 250.111.47.254250.111.47.2554,094
244250.111.48.0/20250.111.48.1 to 250.111.63.254250.111.63.2554,094
245250.111.64.0/20250.111.64.1 to 250.111.79.254250.111.79.2554,094
246250.111.80.0/20250.111.80.1 to 250.111.95.254250.111.95.2554,094
247250.111.96.0/20250.111.96.1 to 250.111.111.254250.111.111.2554,094
248250.111.112.0/20250.111.112.1 to 250.111.127.254250.111.127.2554,094
249250.111.128.0/20250.111.128.1 to 250.111.143.254250.111.143.2554,094
250250.111.144.0/20250.111.144.1 to 250.111.159.254250.111.159.2554,094
251250.111.160.0/20250.111.160.1 to 250.111.175.254250.111.175.2554,094
252250.111.176.0/20250.111.176.1 to 250.111.191.254250.111.191.2554,094
253250.111.192.0/20250.111.192.1 to 250.111.207.254250.111.207.2554,094
254250.111.208.0/20250.111.208.1 to 250.111.223.254250.111.223.2554,094
255250.111.224.0/20250.111.224.1 to 250.111.239.254250.111.239.2554,094
256250.111.240.0/20250.111.240.1 to 250.111.255.254250.111.255.2554,094

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.