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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.

Network241.136.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
241.136.0.0
Broadcast address
241.139.255.255
First usable
241.136.0.1
Last usable
241.139.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Reserved 240.0.0.0/4
Future use; not usable on most systems
Old class
E (reserved)
As numbers
Hex F1880000 · Integer 4052221952 to 4052484095
Reverse DNS zones
136.241.in-addr.arpa
137.241.in-addr.arpa
138.241.in-addr.arpa
139.241.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11110001.10001000.00000000.00000000241.136.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network11110001.10001000.00000000.00000000241.136.0.0
Broadcast11110001.10001011.11111111.11111111241.139.255.255
Split into smaller subnets/22
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

241.136.0.0/14 makes 256 subnets of /22.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1241.136.0.0/22241.136.0.1 to 241.136.3.254241.136.3.2551,022
2241.136.4.0/22241.136.4.1 to 241.136.7.254241.136.7.2551,022
3241.136.8.0/22241.136.8.1 to 241.136.11.254241.136.11.2551,022
4241.136.12.0/22241.136.12.1 to 241.136.15.254241.136.15.2551,022
5241.136.16.0/22241.136.16.1 to 241.136.19.254241.136.19.2551,022
6241.136.20.0/22241.136.20.1 to 241.136.23.254241.136.23.2551,022
7241.136.24.0/22241.136.24.1 to 241.136.27.254241.136.27.2551,022
8241.136.28.0/22241.136.28.1 to 241.136.31.254241.136.31.2551,022
9241.136.32.0/22241.136.32.1 to 241.136.35.254241.136.35.2551,022
10241.136.36.0/22241.136.36.1 to 241.136.39.254241.136.39.2551,022
11241.136.40.0/22241.136.40.1 to 241.136.43.254241.136.43.2551,022
12241.136.44.0/22241.136.44.1 to 241.136.47.254241.136.47.2551,022
13241.136.48.0/22241.136.48.1 to 241.136.51.254241.136.51.2551,022
14241.136.52.0/22241.136.52.1 to 241.136.55.254241.136.55.2551,022
15241.136.56.0/22241.136.56.1 to 241.136.59.254241.136.59.2551,022
16241.136.60.0/22241.136.60.1 to 241.136.63.254241.136.63.2551,022
17241.136.64.0/22241.136.64.1 to 241.136.67.254241.136.67.2551,022
18241.136.68.0/22241.136.68.1 to 241.136.71.254241.136.71.2551,022
19241.136.72.0/22241.136.72.1 to 241.136.75.254241.136.75.2551,022
20241.136.76.0/22241.136.76.1 to 241.136.79.254241.136.79.2551,022
21241.136.80.0/22241.136.80.1 to 241.136.83.254241.136.83.2551,022
22241.136.84.0/22241.136.84.1 to 241.136.87.254241.136.87.2551,022
23241.136.88.0/22241.136.88.1 to 241.136.91.254241.136.91.2551,022
24241.136.92.0/22241.136.92.1 to 241.136.95.254241.136.95.2551,022
25241.136.96.0/22241.136.96.1 to 241.136.99.254241.136.99.2551,022
26241.136.100.0/22241.136.100.1 to 241.136.103.254241.136.103.2551,022
27241.136.104.0/22241.136.104.1 to 241.136.107.254241.136.107.2551,022
28241.136.108.0/22241.136.108.1 to 241.136.111.254241.136.111.2551,022
29241.136.112.0/22241.136.112.1 to 241.136.115.254241.136.115.2551,022
30241.136.116.0/22241.136.116.1 to 241.136.119.254241.136.119.2551,022
31241.136.120.0/22241.136.120.1 to 241.136.123.254241.136.123.2551,022
32241.136.124.0/22241.136.124.1 to 241.136.127.254241.136.127.2551,022
33241.136.128.0/22241.136.128.1 to 241.136.131.254241.136.131.2551,022
34241.136.132.0/22241.136.132.1 to 241.136.135.254241.136.135.2551,022
35241.136.136.0/22241.136.136.1 to 241.136.139.254241.136.139.2551,022
36241.136.140.0/22241.136.140.1 to 241.136.143.254241.136.143.2551,022
37241.136.144.0/22241.136.144.1 to 241.136.147.254241.136.147.2551,022
38241.136.148.0/22241.136.148.1 to 241.136.151.254241.136.151.2551,022
39241.136.152.0/22241.136.152.1 to 241.136.155.254241.136.155.2551,022
40241.136.156.0/22241.136.156.1 to 241.136.159.254241.136.159.2551,022
41241.136.160.0/22241.136.160.1 to 241.136.163.254241.136.163.2551,022
42241.136.164.0/22241.136.164.1 to 241.136.167.254241.136.167.2551,022
43241.136.168.0/22241.136.168.1 to 241.136.171.254241.136.171.2551,022
44241.136.172.0/22241.136.172.1 to 241.136.175.254241.136.175.2551,022
45241.136.176.0/22241.136.176.1 to 241.136.179.254241.136.179.2551,022
46241.136.180.0/22241.136.180.1 to 241.136.183.254241.136.183.2551,022
47241.136.184.0/22241.136.184.1 to 241.136.187.254241.136.187.2551,022
48241.136.188.0/22241.136.188.1 to 241.136.191.254241.136.191.2551,022
49241.136.192.0/22241.136.192.1 to 241.136.195.254241.136.195.2551,022
50241.136.196.0/22241.136.196.1 to 241.136.199.254241.136.199.2551,022
51241.136.200.0/22241.136.200.1 to 241.136.203.254241.136.203.2551,022
52241.136.204.0/22241.136.204.1 to 241.136.207.254241.136.207.2551,022
53241.136.208.0/22241.136.208.1 to 241.136.211.254241.136.211.2551,022
54241.136.212.0/22241.136.212.1 to 241.136.215.254241.136.215.2551,022
55241.136.216.0/22241.136.216.1 to 241.136.219.254241.136.219.2551,022
56241.136.220.0/22241.136.220.1 to 241.136.223.254241.136.223.2551,022
57241.136.224.0/22241.136.224.1 to 241.136.227.254241.136.227.2551,022
58241.136.228.0/22241.136.228.1 to 241.136.231.254241.136.231.2551,022
59241.136.232.0/22241.136.232.1 to 241.136.235.254241.136.235.2551,022
60241.136.236.0/22241.136.236.1 to 241.136.239.254241.136.239.2551,022
61241.136.240.0/22241.136.240.1 to 241.136.243.254241.136.243.2551,022
62241.136.244.0/22241.136.244.1 to 241.136.247.254241.136.247.2551,022
63241.136.248.0/22241.136.248.1 to 241.136.251.254241.136.251.2551,022
64241.136.252.0/22241.136.252.1 to 241.136.255.254241.136.255.2551,022
65241.137.0.0/22241.137.0.1 to 241.137.3.254241.137.3.2551,022
66241.137.4.0/22241.137.4.1 to 241.137.7.254241.137.7.2551,022
67241.137.8.0/22241.137.8.1 to 241.137.11.254241.137.11.2551,022
68241.137.12.0/22241.137.12.1 to 241.137.15.254241.137.15.2551,022
69241.137.16.0/22241.137.16.1 to 241.137.19.254241.137.19.2551,022
70241.137.20.0/22241.137.20.1 to 241.137.23.254241.137.23.2551,022
71241.137.24.0/22241.137.24.1 to 241.137.27.254241.137.27.2551,022
72241.137.28.0/22241.137.28.1 to 241.137.31.254241.137.31.2551,022
73241.137.32.0/22241.137.32.1 to 241.137.35.254241.137.35.2551,022
74241.137.36.0/22241.137.36.1 to 241.137.39.254241.137.39.2551,022
75241.137.40.0/22241.137.40.1 to 241.137.43.254241.137.43.2551,022
76241.137.44.0/22241.137.44.1 to 241.137.47.254241.137.47.2551,022
77241.137.48.0/22241.137.48.1 to 241.137.51.254241.137.51.2551,022
78241.137.52.0/22241.137.52.1 to 241.137.55.254241.137.55.2551,022
79241.137.56.0/22241.137.56.1 to 241.137.59.254241.137.59.2551,022
80241.137.60.0/22241.137.60.1 to 241.137.63.254241.137.63.2551,022
81241.137.64.0/22241.137.64.1 to 241.137.67.254241.137.67.2551,022
82241.137.68.0/22241.137.68.1 to 241.137.71.254241.137.71.2551,022
83241.137.72.0/22241.137.72.1 to 241.137.75.254241.137.75.2551,022
84241.137.76.0/22241.137.76.1 to 241.137.79.254241.137.79.2551,022
85241.137.80.0/22241.137.80.1 to 241.137.83.254241.137.83.2551,022
86241.137.84.0/22241.137.84.1 to 241.137.87.254241.137.87.2551,022
87241.137.88.0/22241.137.88.1 to 241.137.91.254241.137.91.2551,022
88241.137.92.0/22241.137.92.1 to 241.137.95.254241.137.95.2551,022
89241.137.96.0/22241.137.96.1 to 241.137.99.254241.137.99.2551,022
90241.137.100.0/22241.137.100.1 to 241.137.103.254241.137.103.2551,022
91241.137.104.0/22241.137.104.1 to 241.137.107.254241.137.107.2551,022
92241.137.108.0/22241.137.108.1 to 241.137.111.254241.137.111.2551,022
93241.137.112.0/22241.137.112.1 to 241.137.115.254241.137.115.2551,022
94241.137.116.0/22241.137.116.1 to 241.137.119.254241.137.119.2551,022
95241.137.120.0/22241.137.120.1 to 241.137.123.254241.137.123.2551,022
96241.137.124.0/22241.137.124.1 to 241.137.127.254241.137.127.2551,022
97241.137.128.0/22241.137.128.1 to 241.137.131.254241.137.131.2551,022
98241.137.132.0/22241.137.132.1 to 241.137.135.254241.137.135.2551,022
99241.137.136.0/22241.137.136.1 to 241.137.139.254241.137.139.2551,022
100241.137.140.0/22241.137.140.1 to 241.137.143.254241.137.143.2551,022
101241.137.144.0/22241.137.144.1 to 241.137.147.254241.137.147.2551,022
102241.137.148.0/22241.137.148.1 to 241.137.151.254241.137.151.2551,022
103241.137.152.0/22241.137.152.1 to 241.137.155.254241.137.155.2551,022
104241.137.156.0/22241.137.156.1 to 241.137.159.254241.137.159.2551,022
105241.137.160.0/22241.137.160.1 to 241.137.163.254241.137.163.2551,022
106241.137.164.0/22241.137.164.1 to 241.137.167.254241.137.167.2551,022
107241.137.168.0/22241.137.168.1 to 241.137.171.254241.137.171.2551,022
108241.137.172.0/22241.137.172.1 to 241.137.175.254241.137.175.2551,022
109241.137.176.0/22241.137.176.1 to 241.137.179.254241.137.179.2551,022
110241.137.180.0/22241.137.180.1 to 241.137.183.254241.137.183.2551,022
111241.137.184.0/22241.137.184.1 to 241.137.187.254241.137.187.2551,022
112241.137.188.0/22241.137.188.1 to 241.137.191.254241.137.191.2551,022
113241.137.192.0/22241.137.192.1 to 241.137.195.254241.137.195.2551,022
114241.137.196.0/22241.137.196.1 to 241.137.199.254241.137.199.2551,022
115241.137.200.0/22241.137.200.1 to 241.137.203.254241.137.203.2551,022
116241.137.204.0/22241.137.204.1 to 241.137.207.254241.137.207.2551,022
117241.137.208.0/22241.137.208.1 to 241.137.211.254241.137.211.2551,022
118241.137.212.0/22241.137.212.1 to 241.137.215.254241.137.215.2551,022
119241.137.216.0/22241.137.216.1 to 241.137.219.254241.137.219.2551,022
120241.137.220.0/22241.137.220.1 to 241.137.223.254241.137.223.2551,022
121241.137.224.0/22241.137.224.1 to 241.137.227.254241.137.227.2551,022
122241.137.228.0/22241.137.228.1 to 241.137.231.254241.137.231.2551,022
123241.137.232.0/22241.137.232.1 to 241.137.235.254241.137.235.2551,022
124241.137.236.0/22241.137.236.1 to 241.137.239.254241.137.239.2551,022
125241.137.240.0/22241.137.240.1 to 241.137.243.254241.137.243.2551,022
126241.137.244.0/22241.137.244.1 to 241.137.247.254241.137.247.2551,022
127241.137.248.0/22241.137.248.1 to 241.137.251.254241.137.251.2551,022
128241.137.252.0/22241.137.252.1 to 241.137.255.254241.137.255.2551,022
129241.138.0.0/22241.138.0.1 to 241.138.3.254241.138.3.2551,022
130241.138.4.0/22241.138.4.1 to 241.138.7.254241.138.7.2551,022
131241.138.8.0/22241.138.8.1 to 241.138.11.254241.138.11.2551,022
132241.138.12.0/22241.138.12.1 to 241.138.15.254241.138.15.2551,022
133241.138.16.0/22241.138.16.1 to 241.138.19.254241.138.19.2551,022
134241.138.20.0/22241.138.20.1 to 241.138.23.254241.138.23.2551,022
135241.138.24.0/22241.138.24.1 to 241.138.27.254241.138.27.2551,022
136241.138.28.0/22241.138.28.1 to 241.138.31.254241.138.31.2551,022
137241.138.32.0/22241.138.32.1 to 241.138.35.254241.138.35.2551,022
138241.138.36.0/22241.138.36.1 to 241.138.39.254241.138.39.2551,022
139241.138.40.0/22241.138.40.1 to 241.138.43.254241.138.43.2551,022
140241.138.44.0/22241.138.44.1 to 241.138.47.254241.138.47.2551,022
141241.138.48.0/22241.138.48.1 to 241.138.51.254241.138.51.2551,022
142241.138.52.0/22241.138.52.1 to 241.138.55.254241.138.55.2551,022
143241.138.56.0/22241.138.56.1 to 241.138.59.254241.138.59.2551,022
144241.138.60.0/22241.138.60.1 to 241.138.63.254241.138.63.2551,022
145241.138.64.0/22241.138.64.1 to 241.138.67.254241.138.67.2551,022
146241.138.68.0/22241.138.68.1 to 241.138.71.254241.138.71.2551,022
147241.138.72.0/22241.138.72.1 to 241.138.75.254241.138.75.2551,022
148241.138.76.0/22241.138.76.1 to 241.138.79.254241.138.79.2551,022
149241.138.80.0/22241.138.80.1 to 241.138.83.254241.138.83.2551,022
150241.138.84.0/22241.138.84.1 to 241.138.87.254241.138.87.2551,022
151241.138.88.0/22241.138.88.1 to 241.138.91.254241.138.91.2551,022
152241.138.92.0/22241.138.92.1 to 241.138.95.254241.138.95.2551,022
153241.138.96.0/22241.138.96.1 to 241.138.99.254241.138.99.2551,022
154241.138.100.0/22241.138.100.1 to 241.138.103.254241.138.103.2551,022
155241.138.104.0/22241.138.104.1 to 241.138.107.254241.138.107.2551,022
156241.138.108.0/22241.138.108.1 to 241.138.111.254241.138.111.2551,022
157241.138.112.0/22241.138.112.1 to 241.138.115.254241.138.115.2551,022
158241.138.116.0/22241.138.116.1 to 241.138.119.254241.138.119.2551,022
159241.138.120.0/22241.138.120.1 to 241.138.123.254241.138.123.2551,022
160241.138.124.0/22241.138.124.1 to 241.138.127.254241.138.127.2551,022
161241.138.128.0/22241.138.128.1 to 241.138.131.254241.138.131.2551,022
162241.138.132.0/22241.138.132.1 to 241.138.135.254241.138.135.2551,022
163241.138.136.0/22241.138.136.1 to 241.138.139.254241.138.139.2551,022
164241.138.140.0/22241.138.140.1 to 241.138.143.254241.138.143.2551,022
165241.138.144.0/22241.138.144.1 to 241.138.147.254241.138.147.2551,022
166241.138.148.0/22241.138.148.1 to 241.138.151.254241.138.151.2551,022
167241.138.152.0/22241.138.152.1 to 241.138.155.254241.138.155.2551,022
168241.138.156.0/22241.138.156.1 to 241.138.159.254241.138.159.2551,022
169241.138.160.0/22241.138.160.1 to 241.138.163.254241.138.163.2551,022
170241.138.164.0/22241.138.164.1 to 241.138.167.254241.138.167.2551,022
171241.138.168.0/22241.138.168.1 to 241.138.171.254241.138.171.2551,022
172241.138.172.0/22241.138.172.1 to 241.138.175.254241.138.175.2551,022
173241.138.176.0/22241.138.176.1 to 241.138.179.254241.138.179.2551,022
174241.138.180.0/22241.138.180.1 to 241.138.183.254241.138.183.2551,022
175241.138.184.0/22241.138.184.1 to 241.138.187.254241.138.187.2551,022
176241.138.188.0/22241.138.188.1 to 241.138.191.254241.138.191.2551,022
177241.138.192.0/22241.138.192.1 to 241.138.195.254241.138.195.2551,022
178241.138.196.0/22241.138.196.1 to 241.138.199.254241.138.199.2551,022
179241.138.200.0/22241.138.200.1 to 241.138.203.254241.138.203.2551,022
180241.138.204.0/22241.138.204.1 to 241.138.207.254241.138.207.2551,022
181241.138.208.0/22241.138.208.1 to 241.138.211.254241.138.211.2551,022
182241.138.212.0/22241.138.212.1 to 241.138.215.254241.138.215.2551,022
183241.138.216.0/22241.138.216.1 to 241.138.219.254241.138.219.2551,022
184241.138.220.0/22241.138.220.1 to 241.138.223.254241.138.223.2551,022
185241.138.224.0/22241.138.224.1 to 241.138.227.254241.138.227.2551,022
186241.138.228.0/22241.138.228.1 to 241.138.231.254241.138.231.2551,022
187241.138.232.0/22241.138.232.1 to 241.138.235.254241.138.235.2551,022
188241.138.236.0/22241.138.236.1 to 241.138.239.254241.138.239.2551,022
189241.138.240.0/22241.138.240.1 to 241.138.243.254241.138.243.2551,022
190241.138.244.0/22241.138.244.1 to 241.138.247.254241.138.247.2551,022
191241.138.248.0/22241.138.248.1 to 241.138.251.254241.138.251.2551,022
192241.138.252.0/22241.138.252.1 to 241.138.255.254241.138.255.2551,022
193241.139.0.0/22241.139.0.1 to 241.139.3.254241.139.3.2551,022
194241.139.4.0/22241.139.4.1 to 241.139.7.254241.139.7.2551,022
195241.139.8.0/22241.139.8.1 to 241.139.11.254241.139.11.2551,022
196241.139.12.0/22241.139.12.1 to 241.139.15.254241.139.15.2551,022
197241.139.16.0/22241.139.16.1 to 241.139.19.254241.139.19.2551,022
198241.139.20.0/22241.139.20.1 to 241.139.23.254241.139.23.2551,022
199241.139.24.0/22241.139.24.1 to 241.139.27.254241.139.27.2551,022
200241.139.28.0/22241.139.28.1 to 241.139.31.254241.139.31.2551,022
201241.139.32.0/22241.139.32.1 to 241.139.35.254241.139.35.2551,022
202241.139.36.0/22241.139.36.1 to 241.139.39.254241.139.39.2551,022
203241.139.40.0/22241.139.40.1 to 241.139.43.254241.139.43.2551,022
204241.139.44.0/22241.139.44.1 to 241.139.47.254241.139.47.2551,022
205241.139.48.0/22241.139.48.1 to 241.139.51.254241.139.51.2551,022
206241.139.52.0/22241.139.52.1 to 241.139.55.254241.139.55.2551,022
207241.139.56.0/22241.139.56.1 to 241.139.59.254241.139.59.2551,022
208241.139.60.0/22241.139.60.1 to 241.139.63.254241.139.63.2551,022
209241.139.64.0/22241.139.64.1 to 241.139.67.254241.139.67.2551,022
210241.139.68.0/22241.139.68.1 to 241.139.71.254241.139.71.2551,022
211241.139.72.0/22241.139.72.1 to 241.139.75.254241.139.75.2551,022
212241.139.76.0/22241.139.76.1 to 241.139.79.254241.139.79.2551,022
213241.139.80.0/22241.139.80.1 to 241.139.83.254241.139.83.2551,022
214241.139.84.0/22241.139.84.1 to 241.139.87.254241.139.87.2551,022
215241.139.88.0/22241.139.88.1 to 241.139.91.254241.139.91.2551,022
216241.139.92.0/22241.139.92.1 to 241.139.95.254241.139.95.2551,022
217241.139.96.0/22241.139.96.1 to 241.139.99.254241.139.99.2551,022
218241.139.100.0/22241.139.100.1 to 241.139.103.254241.139.103.2551,022
219241.139.104.0/22241.139.104.1 to 241.139.107.254241.139.107.2551,022
220241.139.108.0/22241.139.108.1 to 241.139.111.254241.139.111.2551,022
221241.139.112.0/22241.139.112.1 to 241.139.115.254241.139.115.2551,022
222241.139.116.0/22241.139.116.1 to 241.139.119.254241.139.119.2551,022
223241.139.120.0/22241.139.120.1 to 241.139.123.254241.139.123.2551,022
224241.139.124.0/22241.139.124.1 to 241.139.127.254241.139.127.2551,022
225241.139.128.0/22241.139.128.1 to 241.139.131.254241.139.131.2551,022
226241.139.132.0/22241.139.132.1 to 241.139.135.254241.139.135.2551,022
227241.139.136.0/22241.139.136.1 to 241.139.139.254241.139.139.2551,022
228241.139.140.0/22241.139.140.1 to 241.139.143.254241.139.143.2551,022
229241.139.144.0/22241.139.144.1 to 241.139.147.254241.139.147.2551,022
230241.139.148.0/22241.139.148.1 to 241.139.151.254241.139.151.2551,022
231241.139.152.0/22241.139.152.1 to 241.139.155.254241.139.155.2551,022
232241.139.156.0/22241.139.156.1 to 241.139.159.254241.139.159.2551,022
233241.139.160.0/22241.139.160.1 to 241.139.163.254241.139.163.2551,022
234241.139.164.0/22241.139.164.1 to 241.139.167.254241.139.167.2551,022
235241.139.168.0/22241.139.168.1 to 241.139.171.254241.139.171.2551,022
236241.139.172.0/22241.139.172.1 to 241.139.175.254241.139.175.2551,022
237241.139.176.0/22241.139.176.1 to 241.139.179.254241.139.179.2551,022
238241.139.180.0/22241.139.180.1 to 241.139.183.254241.139.183.2551,022
239241.139.184.0/22241.139.184.1 to 241.139.187.254241.139.187.2551,022
240241.139.188.0/22241.139.188.1 to 241.139.191.254241.139.191.2551,022
241241.139.192.0/22241.139.192.1 to 241.139.195.254241.139.195.2551,022
242241.139.196.0/22241.139.196.1 to 241.139.199.254241.139.199.2551,022
243241.139.200.0/22241.139.200.1 to 241.139.203.254241.139.203.2551,022
244241.139.204.0/22241.139.204.1 to 241.139.207.254241.139.207.2551,022
245241.139.208.0/22241.139.208.1 to 241.139.211.254241.139.211.2551,022
246241.139.212.0/22241.139.212.1 to 241.139.215.254241.139.215.2551,022
247241.139.216.0/22241.139.216.1 to 241.139.219.254241.139.219.2551,022
248241.139.220.0/22241.139.220.1 to 241.139.223.254241.139.223.2551,022
249241.139.224.0/22241.139.224.1 to 241.139.227.254241.139.227.2551,022
250241.139.228.0/22241.139.228.1 to 241.139.231.254241.139.231.2551,022
251241.139.232.0/22241.139.232.1 to 241.139.235.254241.139.235.2551,022
252241.139.236.0/22241.139.236.1 to 241.139.239.254241.139.239.2551,022
253241.139.240.0/22241.139.240.1 to 241.139.243.254241.139.243.2551,022
254241.139.244.0/22241.139.244.1 to 241.139.247.254241.139.247.2551,022
255241.139.248.0/22241.139.248.1 to 241.139.251.254241.139.251.2551,022
256241.139.252.0/22241.139.252.1 to 241.139.255.254241.139.255.2551,022

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.