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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.

Network192.136.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
192.136.0.0
Broadcast address
192.143.255.255
First usable
192.136.0.1
Last usable
192.143.255.254
Usable hosts
524,286 (524,288 less the network and broadcast addresses)
Subnet mask
255.248.0.0
Wildcard mask
0.7.255.255 (Cisco ACLs, OSPF)
Prefix length
/13
Type
Public public
Old class
C (default /24)
As numbers
Hex C0880000 · Integer 3230138368 to 3230662655
Reverse DNS zones
136.192.in-addr.arpa
137.192.in-addr.arpa
138.192.in-addr.arpa
139.192.in-addr.arpa
140.192.in-addr.arpa
141.192.in-addr.arpa
142.192.in-addr.arpa
143.192.in-addr.arpa
/13 is not on a 8-bit boundary, so it takes 8 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11000000.10001000.00000000.00000000192.136.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network11000000.10001000.00000000.00000000192.136.0.0
Broadcast11000000.10001111.11111111.11111111192.143.255.255
Split into smaller subnets/22
/14 (2)/15 (4)/16 (8)/17 (16)/18 (32)/19 (64)/20 (128)/21 (256)/22 (512)/23 (1,024)/24 (2,048)/25 (4,096)

192.136.0.0/13 makes 512 subnets of /22; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1192.136.0.0/22192.136.0.1 to 192.136.3.254192.136.3.2551,022
2192.136.4.0/22192.136.4.1 to 192.136.7.254192.136.7.2551,022
3192.136.8.0/22192.136.8.1 to 192.136.11.254192.136.11.2551,022
4192.136.12.0/22192.136.12.1 to 192.136.15.254192.136.15.2551,022
5192.136.16.0/22192.136.16.1 to 192.136.19.254192.136.19.2551,022
6192.136.20.0/22192.136.20.1 to 192.136.23.254192.136.23.2551,022
7192.136.24.0/22192.136.24.1 to 192.136.27.254192.136.27.2551,022
8192.136.28.0/22192.136.28.1 to 192.136.31.254192.136.31.2551,022
9192.136.32.0/22192.136.32.1 to 192.136.35.254192.136.35.2551,022
10192.136.36.0/22192.136.36.1 to 192.136.39.254192.136.39.2551,022
11192.136.40.0/22192.136.40.1 to 192.136.43.254192.136.43.2551,022
12192.136.44.0/22192.136.44.1 to 192.136.47.254192.136.47.2551,022
13192.136.48.0/22192.136.48.1 to 192.136.51.254192.136.51.2551,022
14192.136.52.0/22192.136.52.1 to 192.136.55.254192.136.55.2551,022
15192.136.56.0/22192.136.56.1 to 192.136.59.254192.136.59.2551,022
16192.136.60.0/22192.136.60.1 to 192.136.63.254192.136.63.2551,022
17192.136.64.0/22192.136.64.1 to 192.136.67.254192.136.67.2551,022
18192.136.68.0/22192.136.68.1 to 192.136.71.254192.136.71.2551,022
19192.136.72.0/22192.136.72.1 to 192.136.75.254192.136.75.2551,022
20192.136.76.0/22192.136.76.1 to 192.136.79.254192.136.79.2551,022
21192.136.80.0/22192.136.80.1 to 192.136.83.254192.136.83.2551,022
22192.136.84.0/22192.136.84.1 to 192.136.87.254192.136.87.2551,022
23192.136.88.0/22192.136.88.1 to 192.136.91.254192.136.91.2551,022
24192.136.92.0/22192.136.92.1 to 192.136.95.254192.136.95.2551,022
25192.136.96.0/22192.136.96.1 to 192.136.99.254192.136.99.2551,022
26192.136.100.0/22192.136.100.1 to 192.136.103.254192.136.103.2551,022
27192.136.104.0/22192.136.104.1 to 192.136.107.254192.136.107.2551,022
28192.136.108.0/22192.136.108.1 to 192.136.111.254192.136.111.2551,022
29192.136.112.0/22192.136.112.1 to 192.136.115.254192.136.115.2551,022
30192.136.116.0/22192.136.116.1 to 192.136.119.254192.136.119.2551,022
31192.136.120.0/22192.136.120.1 to 192.136.123.254192.136.123.2551,022
32192.136.124.0/22192.136.124.1 to 192.136.127.254192.136.127.2551,022
33192.136.128.0/22192.136.128.1 to 192.136.131.254192.136.131.2551,022
34192.136.132.0/22192.136.132.1 to 192.136.135.254192.136.135.2551,022
35192.136.136.0/22192.136.136.1 to 192.136.139.254192.136.139.2551,022
36192.136.140.0/22192.136.140.1 to 192.136.143.254192.136.143.2551,022
37192.136.144.0/22192.136.144.1 to 192.136.147.254192.136.147.2551,022
38192.136.148.0/22192.136.148.1 to 192.136.151.254192.136.151.2551,022
39192.136.152.0/22192.136.152.1 to 192.136.155.254192.136.155.2551,022
40192.136.156.0/22192.136.156.1 to 192.136.159.254192.136.159.2551,022
41192.136.160.0/22192.136.160.1 to 192.136.163.254192.136.163.2551,022
42192.136.164.0/22192.136.164.1 to 192.136.167.254192.136.167.2551,022
43192.136.168.0/22192.136.168.1 to 192.136.171.254192.136.171.2551,022
44192.136.172.0/22192.136.172.1 to 192.136.175.254192.136.175.2551,022
45192.136.176.0/22192.136.176.1 to 192.136.179.254192.136.179.2551,022
46192.136.180.0/22192.136.180.1 to 192.136.183.254192.136.183.2551,022
47192.136.184.0/22192.136.184.1 to 192.136.187.254192.136.187.2551,022
48192.136.188.0/22192.136.188.1 to 192.136.191.254192.136.191.2551,022
49192.136.192.0/22192.136.192.1 to 192.136.195.254192.136.195.2551,022
50192.136.196.0/22192.136.196.1 to 192.136.199.254192.136.199.2551,022
51192.136.200.0/22192.136.200.1 to 192.136.203.254192.136.203.2551,022
52192.136.204.0/22192.136.204.1 to 192.136.207.254192.136.207.2551,022
53192.136.208.0/22192.136.208.1 to 192.136.211.254192.136.211.2551,022
54192.136.212.0/22192.136.212.1 to 192.136.215.254192.136.215.2551,022
55192.136.216.0/22192.136.216.1 to 192.136.219.254192.136.219.2551,022
56192.136.220.0/22192.136.220.1 to 192.136.223.254192.136.223.2551,022
57192.136.224.0/22192.136.224.1 to 192.136.227.254192.136.227.2551,022
58192.136.228.0/22192.136.228.1 to 192.136.231.254192.136.231.2551,022
59192.136.232.0/22192.136.232.1 to 192.136.235.254192.136.235.2551,022
60192.136.236.0/22192.136.236.1 to 192.136.239.254192.136.239.2551,022
61192.136.240.0/22192.136.240.1 to 192.136.243.254192.136.243.2551,022
62192.136.244.0/22192.136.244.1 to 192.136.247.254192.136.247.2551,022
63192.136.248.0/22192.136.248.1 to 192.136.251.254192.136.251.2551,022
64192.136.252.0/22192.136.252.1 to 192.136.255.254192.136.255.2551,022
65192.137.0.0/22192.137.0.1 to 192.137.3.254192.137.3.2551,022
66192.137.4.0/22192.137.4.1 to 192.137.7.254192.137.7.2551,022
67192.137.8.0/22192.137.8.1 to 192.137.11.254192.137.11.2551,022
68192.137.12.0/22192.137.12.1 to 192.137.15.254192.137.15.2551,022
69192.137.16.0/22192.137.16.1 to 192.137.19.254192.137.19.2551,022
70192.137.20.0/22192.137.20.1 to 192.137.23.254192.137.23.2551,022
71192.137.24.0/22192.137.24.1 to 192.137.27.254192.137.27.2551,022
72192.137.28.0/22192.137.28.1 to 192.137.31.254192.137.31.2551,022
73192.137.32.0/22192.137.32.1 to 192.137.35.254192.137.35.2551,022
74192.137.36.0/22192.137.36.1 to 192.137.39.254192.137.39.2551,022
75192.137.40.0/22192.137.40.1 to 192.137.43.254192.137.43.2551,022
76192.137.44.0/22192.137.44.1 to 192.137.47.254192.137.47.2551,022
77192.137.48.0/22192.137.48.1 to 192.137.51.254192.137.51.2551,022
78192.137.52.0/22192.137.52.1 to 192.137.55.254192.137.55.2551,022
79192.137.56.0/22192.137.56.1 to 192.137.59.254192.137.59.2551,022
80192.137.60.0/22192.137.60.1 to 192.137.63.254192.137.63.2551,022
81192.137.64.0/22192.137.64.1 to 192.137.67.254192.137.67.2551,022
82192.137.68.0/22192.137.68.1 to 192.137.71.254192.137.71.2551,022
83192.137.72.0/22192.137.72.1 to 192.137.75.254192.137.75.2551,022
84192.137.76.0/22192.137.76.1 to 192.137.79.254192.137.79.2551,022
85192.137.80.0/22192.137.80.1 to 192.137.83.254192.137.83.2551,022
86192.137.84.0/22192.137.84.1 to 192.137.87.254192.137.87.2551,022
87192.137.88.0/22192.137.88.1 to 192.137.91.254192.137.91.2551,022
88192.137.92.0/22192.137.92.1 to 192.137.95.254192.137.95.2551,022
89192.137.96.0/22192.137.96.1 to 192.137.99.254192.137.99.2551,022
90192.137.100.0/22192.137.100.1 to 192.137.103.254192.137.103.2551,022
91192.137.104.0/22192.137.104.1 to 192.137.107.254192.137.107.2551,022
92192.137.108.0/22192.137.108.1 to 192.137.111.254192.137.111.2551,022
93192.137.112.0/22192.137.112.1 to 192.137.115.254192.137.115.2551,022
94192.137.116.0/22192.137.116.1 to 192.137.119.254192.137.119.2551,022
95192.137.120.0/22192.137.120.1 to 192.137.123.254192.137.123.2551,022
96192.137.124.0/22192.137.124.1 to 192.137.127.254192.137.127.2551,022
97192.137.128.0/22192.137.128.1 to 192.137.131.254192.137.131.2551,022
98192.137.132.0/22192.137.132.1 to 192.137.135.254192.137.135.2551,022
99192.137.136.0/22192.137.136.1 to 192.137.139.254192.137.139.2551,022
100192.137.140.0/22192.137.140.1 to 192.137.143.254192.137.143.2551,022
101192.137.144.0/22192.137.144.1 to 192.137.147.254192.137.147.2551,022
102192.137.148.0/22192.137.148.1 to 192.137.151.254192.137.151.2551,022
103192.137.152.0/22192.137.152.1 to 192.137.155.254192.137.155.2551,022
104192.137.156.0/22192.137.156.1 to 192.137.159.254192.137.159.2551,022
105192.137.160.0/22192.137.160.1 to 192.137.163.254192.137.163.2551,022
106192.137.164.0/22192.137.164.1 to 192.137.167.254192.137.167.2551,022
107192.137.168.0/22192.137.168.1 to 192.137.171.254192.137.171.2551,022
108192.137.172.0/22192.137.172.1 to 192.137.175.254192.137.175.2551,022
109192.137.176.0/22192.137.176.1 to 192.137.179.254192.137.179.2551,022
110192.137.180.0/22192.137.180.1 to 192.137.183.254192.137.183.2551,022
111192.137.184.0/22192.137.184.1 to 192.137.187.254192.137.187.2551,022
112192.137.188.0/22192.137.188.1 to 192.137.191.254192.137.191.2551,022
113192.137.192.0/22192.137.192.1 to 192.137.195.254192.137.195.2551,022
114192.137.196.0/22192.137.196.1 to 192.137.199.254192.137.199.2551,022
115192.137.200.0/22192.137.200.1 to 192.137.203.254192.137.203.2551,022
116192.137.204.0/22192.137.204.1 to 192.137.207.254192.137.207.2551,022
117192.137.208.0/22192.137.208.1 to 192.137.211.254192.137.211.2551,022
118192.137.212.0/22192.137.212.1 to 192.137.215.254192.137.215.2551,022
119192.137.216.0/22192.137.216.1 to 192.137.219.254192.137.219.2551,022
120192.137.220.0/22192.137.220.1 to 192.137.223.254192.137.223.2551,022
121192.137.224.0/22192.137.224.1 to 192.137.227.254192.137.227.2551,022
122192.137.228.0/22192.137.228.1 to 192.137.231.254192.137.231.2551,022
123192.137.232.0/22192.137.232.1 to 192.137.235.254192.137.235.2551,022
124192.137.236.0/22192.137.236.1 to 192.137.239.254192.137.239.2551,022
125192.137.240.0/22192.137.240.1 to 192.137.243.254192.137.243.2551,022
126192.137.244.0/22192.137.244.1 to 192.137.247.254192.137.247.2551,022
127192.137.248.0/22192.137.248.1 to 192.137.251.254192.137.251.2551,022
128192.137.252.0/22192.137.252.1 to 192.137.255.254192.137.255.2551,022
129192.138.0.0/22192.138.0.1 to 192.138.3.254192.138.3.2551,022
130192.138.4.0/22192.138.4.1 to 192.138.7.254192.138.7.2551,022
131192.138.8.0/22192.138.8.1 to 192.138.11.254192.138.11.2551,022
132192.138.12.0/22192.138.12.1 to 192.138.15.254192.138.15.2551,022
133192.138.16.0/22192.138.16.1 to 192.138.19.254192.138.19.2551,022
134192.138.20.0/22192.138.20.1 to 192.138.23.254192.138.23.2551,022
135192.138.24.0/22192.138.24.1 to 192.138.27.254192.138.27.2551,022
136192.138.28.0/22192.138.28.1 to 192.138.31.254192.138.31.2551,022
137192.138.32.0/22192.138.32.1 to 192.138.35.254192.138.35.2551,022
138192.138.36.0/22192.138.36.1 to 192.138.39.254192.138.39.2551,022
139192.138.40.0/22192.138.40.1 to 192.138.43.254192.138.43.2551,022
140192.138.44.0/22192.138.44.1 to 192.138.47.254192.138.47.2551,022
141192.138.48.0/22192.138.48.1 to 192.138.51.254192.138.51.2551,022
142192.138.52.0/22192.138.52.1 to 192.138.55.254192.138.55.2551,022
143192.138.56.0/22192.138.56.1 to 192.138.59.254192.138.59.2551,022
144192.138.60.0/22192.138.60.1 to 192.138.63.254192.138.63.2551,022
145192.138.64.0/22192.138.64.1 to 192.138.67.254192.138.67.2551,022
146192.138.68.0/22192.138.68.1 to 192.138.71.254192.138.71.2551,022
147192.138.72.0/22192.138.72.1 to 192.138.75.254192.138.75.2551,022
148192.138.76.0/22192.138.76.1 to 192.138.79.254192.138.79.2551,022
149192.138.80.0/22192.138.80.1 to 192.138.83.254192.138.83.2551,022
150192.138.84.0/22192.138.84.1 to 192.138.87.254192.138.87.2551,022
151192.138.88.0/22192.138.88.1 to 192.138.91.254192.138.91.2551,022
152192.138.92.0/22192.138.92.1 to 192.138.95.254192.138.95.2551,022
153192.138.96.0/22192.138.96.1 to 192.138.99.254192.138.99.2551,022
154192.138.100.0/22192.138.100.1 to 192.138.103.254192.138.103.2551,022
155192.138.104.0/22192.138.104.1 to 192.138.107.254192.138.107.2551,022
156192.138.108.0/22192.138.108.1 to 192.138.111.254192.138.111.2551,022
157192.138.112.0/22192.138.112.1 to 192.138.115.254192.138.115.2551,022
158192.138.116.0/22192.138.116.1 to 192.138.119.254192.138.119.2551,022
159192.138.120.0/22192.138.120.1 to 192.138.123.254192.138.123.2551,022
160192.138.124.0/22192.138.124.1 to 192.138.127.254192.138.127.2551,022
161192.138.128.0/22192.138.128.1 to 192.138.131.254192.138.131.2551,022
162192.138.132.0/22192.138.132.1 to 192.138.135.254192.138.135.2551,022
163192.138.136.0/22192.138.136.1 to 192.138.139.254192.138.139.2551,022
164192.138.140.0/22192.138.140.1 to 192.138.143.254192.138.143.2551,022
165192.138.144.0/22192.138.144.1 to 192.138.147.254192.138.147.2551,022
166192.138.148.0/22192.138.148.1 to 192.138.151.254192.138.151.2551,022
167192.138.152.0/22192.138.152.1 to 192.138.155.254192.138.155.2551,022
168192.138.156.0/22192.138.156.1 to 192.138.159.254192.138.159.2551,022
169192.138.160.0/22192.138.160.1 to 192.138.163.254192.138.163.2551,022
170192.138.164.0/22192.138.164.1 to 192.138.167.254192.138.167.2551,022
171192.138.168.0/22192.138.168.1 to 192.138.171.254192.138.171.2551,022
172192.138.172.0/22192.138.172.1 to 192.138.175.254192.138.175.2551,022
173192.138.176.0/22192.138.176.1 to 192.138.179.254192.138.179.2551,022
174192.138.180.0/22192.138.180.1 to 192.138.183.254192.138.183.2551,022
175192.138.184.0/22192.138.184.1 to 192.138.187.254192.138.187.2551,022
176192.138.188.0/22192.138.188.1 to 192.138.191.254192.138.191.2551,022
177192.138.192.0/22192.138.192.1 to 192.138.195.254192.138.195.2551,022
178192.138.196.0/22192.138.196.1 to 192.138.199.254192.138.199.2551,022
179192.138.200.0/22192.138.200.1 to 192.138.203.254192.138.203.2551,022
180192.138.204.0/22192.138.204.1 to 192.138.207.254192.138.207.2551,022
181192.138.208.0/22192.138.208.1 to 192.138.211.254192.138.211.2551,022
182192.138.212.0/22192.138.212.1 to 192.138.215.254192.138.215.2551,022
183192.138.216.0/22192.138.216.1 to 192.138.219.254192.138.219.2551,022
184192.138.220.0/22192.138.220.1 to 192.138.223.254192.138.223.2551,022
185192.138.224.0/22192.138.224.1 to 192.138.227.254192.138.227.2551,022
186192.138.228.0/22192.138.228.1 to 192.138.231.254192.138.231.2551,022
187192.138.232.0/22192.138.232.1 to 192.138.235.254192.138.235.2551,022
188192.138.236.0/22192.138.236.1 to 192.138.239.254192.138.239.2551,022
189192.138.240.0/22192.138.240.1 to 192.138.243.254192.138.243.2551,022
190192.138.244.0/22192.138.244.1 to 192.138.247.254192.138.247.2551,022
191192.138.248.0/22192.138.248.1 to 192.138.251.254192.138.251.2551,022
192192.138.252.0/22192.138.252.1 to 192.138.255.254192.138.255.2551,022
193192.139.0.0/22192.139.0.1 to 192.139.3.254192.139.3.2551,022
194192.139.4.0/22192.139.4.1 to 192.139.7.254192.139.7.2551,022
195192.139.8.0/22192.139.8.1 to 192.139.11.254192.139.11.2551,022
196192.139.12.0/22192.139.12.1 to 192.139.15.254192.139.15.2551,022
197192.139.16.0/22192.139.16.1 to 192.139.19.254192.139.19.2551,022
198192.139.20.0/22192.139.20.1 to 192.139.23.254192.139.23.2551,022
199192.139.24.0/22192.139.24.1 to 192.139.27.254192.139.27.2551,022
200192.139.28.0/22192.139.28.1 to 192.139.31.254192.139.31.2551,022
201192.139.32.0/22192.139.32.1 to 192.139.35.254192.139.35.2551,022
202192.139.36.0/22192.139.36.1 to 192.139.39.254192.139.39.2551,022
203192.139.40.0/22192.139.40.1 to 192.139.43.254192.139.43.2551,022
204192.139.44.0/22192.139.44.1 to 192.139.47.254192.139.47.2551,022
205192.139.48.0/22192.139.48.1 to 192.139.51.254192.139.51.2551,022
206192.139.52.0/22192.139.52.1 to 192.139.55.254192.139.55.2551,022
207192.139.56.0/22192.139.56.1 to 192.139.59.254192.139.59.2551,022
208192.139.60.0/22192.139.60.1 to 192.139.63.254192.139.63.2551,022
209192.139.64.0/22192.139.64.1 to 192.139.67.254192.139.67.2551,022
210192.139.68.0/22192.139.68.1 to 192.139.71.254192.139.71.2551,022
211192.139.72.0/22192.139.72.1 to 192.139.75.254192.139.75.2551,022
212192.139.76.0/22192.139.76.1 to 192.139.79.254192.139.79.2551,022
213192.139.80.0/22192.139.80.1 to 192.139.83.254192.139.83.2551,022
214192.139.84.0/22192.139.84.1 to 192.139.87.254192.139.87.2551,022
215192.139.88.0/22192.139.88.1 to 192.139.91.254192.139.91.2551,022
216192.139.92.0/22192.139.92.1 to 192.139.95.254192.139.95.2551,022
217192.139.96.0/22192.139.96.1 to 192.139.99.254192.139.99.2551,022
218192.139.100.0/22192.139.100.1 to 192.139.103.254192.139.103.2551,022
219192.139.104.0/22192.139.104.1 to 192.139.107.254192.139.107.2551,022
220192.139.108.0/22192.139.108.1 to 192.139.111.254192.139.111.2551,022
221192.139.112.0/22192.139.112.1 to 192.139.115.254192.139.115.2551,022
222192.139.116.0/22192.139.116.1 to 192.139.119.254192.139.119.2551,022
223192.139.120.0/22192.139.120.1 to 192.139.123.254192.139.123.2551,022
224192.139.124.0/22192.139.124.1 to 192.139.127.254192.139.127.2551,022
225192.139.128.0/22192.139.128.1 to 192.139.131.254192.139.131.2551,022
226192.139.132.0/22192.139.132.1 to 192.139.135.254192.139.135.2551,022
227192.139.136.0/22192.139.136.1 to 192.139.139.254192.139.139.2551,022
228192.139.140.0/22192.139.140.1 to 192.139.143.254192.139.143.2551,022
229192.139.144.0/22192.139.144.1 to 192.139.147.254192.139.147.2551,022
230192.139.148.0/22192.139.148.1 to 192.139.151.254192.139.151.2551,022
231192.139.152.0/22192.139.152.1 to 192.139.155.254192.139.155.2551,022
232192.139.156.0/22192.139.156.1 to 192.139.159.254192.139.159.2551,022
233192.139.160.0/22192.139.160.1 to 192.139.163.254192.139.163.2551,022
234192.139.164.0/22192.139.164.1 to 192.139.167.254192.139.167.2551,022
235192.139.168.0/22192.139.168.1 to 192.139.171.254192.139.171.2551,022
236192.139.172.0/22192.139.172.1 to 192.139.175.254192.139.175.2551,022
237192.139.176.0/22192.139.176.1 to 192.139.179.254192.139.179.2551,022
238192.139.180.0/22192.139.180.1 to 192.139.183.254192.139.183.2551,022
239192.139.184.0/22192.139.184.1 to 192.139.187.254192.139.187.2551,022
240192.139.188.0/22192.139.188.1 to 192.139.191.254192.139.191.2551,022
241192.139.192.0/22192.139.192.1 to 192.139.195.254192.139.195.2551,022
242192.139.196.0/22192.139.196.1 to 192.139.199.254192.139.199.2551,022
243192.139.200.0/22192.139.200.1 to 192.139.203.254192.139.203.2551,022
244192.139.204.0/22192.139.204.1 to 192.139.207.254192.139.207.2551,022
245192.139.208.0/22192.139.208.1 to 192.139.211.254192.139.211.2551,022
246192.139.212.0/22192.139.212.1 to 192.139.215.254192.139.215.2551,022
247192.139.216.0/22192.139.216.1 to 192.139.219.254192.139.219.2551,022
248192.139.220.0/22192.139.220.1 to 192.139.223.254192.139.223.2551,022
249192.139.224.0/22192.139.224.1 to 192.139.227.254192.139.227.2551,022
250192.139.228.0/22192.139.228.1 to 192.139.231.254192.139.231.2551,022
251192.139.232.0/22192.139.232.1 to 192.139.235.254192.139.235.2551,022
252192.139.236.0/22192.139.236.1 to 192.139.239.254192.139.239.2551,022
253192.139.240.0/22192.139.240.1 to 192.139.243.254192.139.243.2551,022
254192.139.244.0/22192.139.244.1 to 192.139.247.254192.139.247.2551,022
255192.139.248.0/22192.139.248.1 to 192.139.251.254192.139.251.2551,022
256192.139.252.0/22192.139.252.1 to 192.139.255.254192.139.255.2551,022

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.