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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/23
/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 1,024 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1192.136.0.0/23192.136.0.1 to 192.136.1.254192.136.1.255510
2192.136.2.0/23192.136.2.1 to 192.136.3.254192.136.3.255510
3192.136.4.0/23192.136.4.1 to 192.136.5.254192.136.5.255510
4192.136.6.0/23192.136.6.1 to 192.136.7.254192.136.7.255510
5192.136.8.0/23192.136.8.1 to 192.136.9.254192.136.9.255510
6192.136.10.0/23192.136.10.1 to 192.136.11.254192.136.11.255510
7192.136.12.0/23192.136.12.1 to 192.136.13.254192.136.13.255510
8192.136.14.0/23192.136.14.1 to 192.136.15.254192.136.15.255510
9192.136.16.0/23192.136.16.1 to 192.136.17.254192.136.17.255510
10192.136.18.0/23192.136.18.1 to 192.136.19.254192.136.19.255510
11192.136.20.0/23192.136.20.1 to 192.136.21.254192.136.21.255510
12192.136.22.0/23192.136.22.1 to 192.136.23.254192.136.23.255510
13192.136.24.0/23192.136.24.1 to 192.136.25.254192.136.25.255510
14192.136.26.0/23192.136.26.1 to 192.136.27.254192.136.27.255510
15192.136.28.0/23192.136.28.1 to 192.136.29.254192.136.29.255510
16192.136.30.0/23192.136.30.1 to 192.136.31.254192.136.31.255510
17192.136.32.0/23192.136.32.1 to 192.136.33.254192.136.33.255510
18192.136.34.0/23192.136.34.1 to 192.136.35.254192.136.35.255510
19192.136.36.0/23192.136.36.1 to 192.136.37.254192.136.37.255510
20192.136.38.0/23192.136.38.1 to 192.136.39.254192.136.39.255510
21192.136.40.0/23192.136.40.1 to 192.136.41.254192.136.41.255510
22192.136.42.0/23192.136.42.1 to 192.136.43.254192.136.43.255510
23192.136.44.0/23192.136.44.1 to 192.136.45.254192.136.45.255510
24192.136.46.0/23192.136.46.1 to 192.136.47.254192.136.47.255510
25192.136.48.0/23192.136.48.1 to 192.136.49.254192.136.49.255510
26192.136.50.0/23192.136.50.1 to 192.136.51.254192.136.51.255510
27192.136.52.0/23192.136.52.1 to 192.136.53.254192.136.53.255510
28192.136.54.0/23192.136.54.1 to 192.136.55.254192.136.55.255510
29192.136.56.0/23192.136.56.1 to 192.136.57.254192.136.57.255510
30192.136.58.0/23192.136.58.1 to 192.136.59.254192.136.59.255510
31192.136.60.0/23192.136.60.1 to 192.136.61.254192.136.61.255510
32192.136.62.0/23192.136.62.1 to 192.136.63.254192.136.63.255510
33192.136.64.0/23192.136.64.1 to 192.136.65.254192.136.65.255510
34192.136.66.0/23192.136.66.1 to 192.136.67.254192.136.67.255510
35192.136.68.0/23192.136.68.1 to 192.136.69.254192.136.69.255510
36192.136.70.0/23192.136.70.1 to 192.136.71.254192.136.71.255510
37192.136.72.0/23192.136.72.1 to 192.136.73.254192.136.73.255510
38192.136.74.0/23192.136.74.1 to 192.136.75.254192.136.75.255510
39192.136.76.0/23192.136.76.1 to 192.136.77.254192.136.77.255510
40192.136.78.0/23192.136.78.1 to 192.136.79.254192.136.79.255510
41192.136.80.0/23192.136.80.1 to 192.136.81.254192.136.81.255510
42192.136.82.0/23192.136.82.1 to 192.136.83.254192.136.83.255510
43192.136.84.0/23192.136.84.1 to 192.136.85.254192.136.85.255510
44192.136.86.0/23192.136.86.1 to 192.136.87.254192.136.87.255510
45192.136.88.0/23192.136.88.1 to 192.136.89.254192.136.89.255510
46192.136.90.0/23192.136.90.1 to 192.136.91.254192.136.91.255510
47192.136.92.0/23192.136.92.1 to 192.136.93.254192.136.93.255510
48192.136.94.0/23192.136.94.1 to 192.136.95.254192.136.95.255510
49192.136.96.0/23192.136.96.1 to 192.136.97.254192.136.97.255510
50192.136.98.0/23192.136.98.1 to 192.136.99.254192.136.99.255510
51192.136.100.0/23192.136.100.1 to 192.136.101.254192.136.101.255510
52192.136.102.0/23192.136.102.1 to 192.136.103.254192.136.103.255510
53192.136.104.0/23192.136.104.1 to 192.136.105.254192.136.105.255510
54192.136.106.0/23192.136.106.1 to 192.136.107.254192.136.107.255510
55192.136.108.0/23192.136.108.1 to 192.136.109.254192.136.109.255510
56192.136.110.0/23192.136.110.1 to 192.136.111.254192.136.111.255510
57192.136.112.0/23192.136.112.1 to 192.136.113.254192.136.113.255510
58192.136.114.0/23192.136.114.1 to 192.136.115.254192.136.115.255510
59192.136.116.0/23192.136.116.1 to 192.136.117.254192.136.117.255510
60192.136.118.0/23192.136.118.1 to 192.136.119.254192.136.119.255510
61192.136.120.0/23192.136.120.1 to 192.136.121.254192.136.121.255510
62192.136.122.0/23192.136.122.1 to 192.136.123.254192.136.123.255510
63192.136.124.0/23192.136.124.1 to 192.136.125.254192.136.125.255510
64192.136.126.0/23192.136.126.1 to 192.136.127.254192.136.127.255510
65192.136.128.0/23192.136.128.1 to 192.136.129.254192.136.129.255510
66192.136.130.0/23192.136.130.1 to 192.136.131.254192.136.131.255510
67192.136.132.0/23192.136.132.1 to 192.136.133.254192.136.133.255510
68192.136.134.0/23192.136.134.1 to 192.136.135.254192.136.135.255510
69192.136.136.0/23192.136.136.1 to 192.136.137.254192.136.137.255510
70192.136.138.0/23192.136.138.1 to 192.136.139.254192.136.139.255510
71192.136.140.0/23192.136.140.1 to 192.136.141.254192.136.141.255510
72192.136.142.0/23192.136.142.1 to 192.136.143.254192.136.143.255510
73192.136.144.0/23192.136.144.1 to 192.136.145.254192.136.145.255510
74192.136.146.0/23192.136.146.1 to 192.136.147.254192.136.147.255510
75192.136.148.0/23192.136.148.1 to 192.136.149.254192.136.149.255510
76192.136.150.0/23192.136.150.1 to 192.136.151.254192.136.151.255510
77192.136.152.0/23192.136.152.1 to 192.136.153.254192.136.153.255510
78192.136.154.0/23192.136.154.1 to 192.136.155.254192.136.155.255510
79192.136.156.0/23192.136.156.1 to 192.136.157.254192.136.157.255510
80192.136.158.0/23192.136.158.1 to 192.136.159.254192.136.159.255510
81192.136.160.0/23192.136.160.1 to 192.136.161.254192.136.161.255510
82192.136.162.0/23192.136.162.1 to 192.136.163.254192.136.163.255510
83192.136.164.0/23192.136.164.1 to 192.136.165.254192.136.165.255510
84192.136.166.0/23192.136.166.1 to 192.136.167.254192.136.167.255510
85192.136.168.0/23192.136.168.1 to 192.136.169.254192.136.169.255510
86192.136.170.0/23192.136.170.1 to 192.136.171.254192.136.171.255510
87192.136.172.0/23192.136.172.1 to 192.136.173.254192.136.173.255510
88192.136.174.0/23192.136.174.1 to 192.136.175.254192.136.175.255510
89192.136.176.0/23192.136.176.1 to 192.136.177.254192.136.177.255510
90192.136.178.0/23192.136.178.1 to 192.136.179.254192.136.179.255510
91192.136.180.0/23192.136.180.1 to 192.136.181.254192.136.181.255510
92192.136.182.0/23192.136.182.1 to 192.136.183.254192.136.183.255510
93192.136.184.0/23192.136.184.1 to 192.136.185.254192.136.185.255510
94192.136.186.0/23192.136.186.1 to 192.136.187.254192.136.187.255510
95192.136.188.0/23192.136.188.1 to 192.136.189.254192.136.189.255510
96192.136.190.0/23192.136.190.1 to 192.136.191.254192.136.191.255510
97192.136.192.0/23192.136.192.1 to 192.136.193.254192.136.193.255510
98192.136.194.0/23192.136.194.1 to 192.136.195.254192.136.195.255510
99192.136.196.0/23192.136.196.1 to 192.136.197.254192.136.197.255510
100192.136.198.0/23192.136.198.1 to 192.136.199.254192.136.199.255510
101192.136.200.0/23192.136.200.1 to 192.136.201.254192.136.201.255510
102192.136.202.0/23192.136.202.1 to 192.136.203.254192.136.203.255510
103192.136.204.0/23192.136.204.1 to 192.136.205.254192.136.205.255510
104192.136.206.0/23192.136.206.1 to 192.136.207.254192.136.207.255510
105192.136.208.0/23192.136.208.1 to 192.136.209.254192.136.209.255510
106192.136.210.0/23192.136.210.1 to 192.136.211.254192.136.211.255510
107192.136.212.0/23192.136.212.1 to 192.136.213.254192.136.213.255510
108192.136.214.0/23192.136.214.1 to 192.136.215.254192.136.215.255510
109192.136.216.0/23192.136.216.1 to 192.136.217.254192.136.217.255510
110192.136.218.0/23192.136.218.1 to 192.136.219.254192.136.219.255510
111192.136.220.0/23192.136.220.1 to 192.136.221.254192.136.221.255510
112192.136.222.0/23192.136.222.1 to 192.136.223.254192.136.223.255510
113192.136.224.0/23192.136.224.1 to 192.136.225.254192.136.225.255510
114192.136.226.0/23192.136.226.1 to 192.136.227.254192.136.227.255510
115192.136.228.0/23192.136.228.1 to 192.136.229.254192.136.229.255510
116192.136.230.0/23192.136.230.1 to 192.136.231.254192.136.231.255510
117192.136.232.0/23192.136.232.1 to 192.136.233.254192.136.233.255510
118192.136.234.0/23192.136.234.1 to 192.136.235.254192.136.235.255510
119192.136.236.0/23192.136.236.1 to 192.136.237.254192.136.237.255510
120192.136.238.0/23192.136.238.1 to 192.136.239.254192.136.239.255510
121192.136.240.0/23192.136.240.1 to 192.136.241.254192.136.241.255510
122192.136.242.0/23192.136.242.1 to 192.136.243.254192.136.243.255510
123192.136.244.0/23192.136.244.1 to 192.136.245.254192.136.245.255510
124192.136.246.0/23192.136.246.1 to 192.136.247.254192.136.247.255510
125192.136.248.0/23192.136.248.1 to 192.136.249.254192.136.249.255510
126192.136.250.0/23192.136.250.1 to 192.136.251.254192.136.251.255510
127192.136.252.0/23192.136.252.1 to 192.136.253.254192.136.253.255510
128192.136.254.0/23192.136.254.1 to 192.136.255.254192.136.255.255510
129192.137.0.0/23192.137.0.1 to 192.137.1.254192.137.1.255510
130192.137.2.0/23192.137.2.1 to 192.137.3.254192.137.3.255510
131192.137.4.0/23192.137.4.1 to 192.137.5.254192.137.5.255510
132192.137.6.0/23192.137.6.1 to 192.137.7.254192.137.7.255510
133192.137.8.0/23192.137.8.1 to 192.137.9.254192.137.9.255510
134192.137.10.0/23192.137.10.1 to 192.137.11.254192.137.11.255510
135192.137.12.0/23192.137.12.1 to 192.137.13.254192.137.13.255510
136192.137.14.0/23192.137.14.1 to 192.137.15.254192.137.15.255510
137192.137.16.0/23192.137.16.1 to 192.137.17.254192.137.17.255510
138192.137.18.0/23192.137.18.1 to 192.137.19.254192.137.19.255510
139192.137.20.0/23192.137.20.1 to 192.137.21.254192.137.21.255510
140192.137.22.0/23192.137.22.1 to 192.137.23.254192.137.23.255510
141192.137.24.0/23192.137.24.1 to 192.137.25.254192.137.25.255510
142192.137.26.0/23192.137.26.1 to 192.137.27.254192.137.27.255510
143192.137.28.0/23192.137.28.1 to 192.137.29.254192.137.29.255510
144192.137.30.0/23192.137.30.1 to 192.137.31.254192.137.31.255510
145192.137.32.0/23192.137.32.1 to 192.137.33.254192.137.33.255510
146192.137.34.0/23192.137.34.1 to 192.137.35.254192.137.35.255510
147192.137.36.0/23192.137.36.1 to 192.137.37.254192.137.37.255510
148192.137.38.0/23192.137.38.1 to 192.137.39.254192.137.39.255510
149192.137.40.0/23192.137.40.1 to 192.137.41.254192.137.41.255510
150192.137.42.0/23192.137.42.1 to 192.137.43.254192.137.43.255510
151192.137.44.0/23192.137.44.1 to 192.137.45.254192.137.45.255510
152192.137.46.0/23192.137.46.1 to 192.137.47.254192.137.47.255510
153192.137.48.0/23192.137.48.1 to 192.137.49.254192.137.49.255510
154192.137.50.0/23192.137.50.1 to 192.137.51.254192.137.51.255510
155192.137.52.0/23192.137.52.1 to 192.137.53.254192.137.53.255510
156192.137.54.0/23192.137.54.1 to 192.137.55.254192.137.55.255510
157192.137.56.0/23192.137.56.1 to 192.137.57.254192.137.57.255510
158192.137.58.0/23192.137.58.1 to 192.137.59.254192.137.59.255510
159192.137.60.0/23192.137.60.1 to 192.137.61.254192.137.61.255510
160192.137.62.0/23192.137.62.1 to 192.137.63.254192.137.63.255510
161192.137.64.0/23192.137.64.1 to 192.137.65.254192.137.65.255510
162192.137.66.0/23192.137.66.1 to 192.137.67.254192.137.67.255510
163192.137.68.0/23192.137.68.1 to 192.137.69.254192.137.69.255510
164192.137.70.0/23192.137.70.1 to 192.137.71.254192.137.71.255510
165192.137.72.0/23192.137.72.1 to 192.137.73.254192.137.73.255510
166192.137.74.0/23192.137.74.1 to 192.137.75.254192.137.75.255510
167192.137.76.0/23192.137.76.1 to 192.137.77.254192.137.77.255510
168192.137.78.0/23192.137.78.1 to 192.137.79.254192.137.79.255510
169192.137.80.0/23192.137.80.1 to 192.137.81.254192.137.81.255510
170192.137.82.0/23192.137.82.1 to 192.137.83.254192.137.83.255510
171192.137.84.0/23192.137.84.1 to 192.137.85.254192.137.85.255510
172192.137.86.0/23192.137.86.1 to 192.137.87.254192.137.87.255510
173192.137.88.0/23192.137.88.1 to 192.137.89.254192.137.89.255510
174192.137.90.0/23192.137.90.1 to 192.137.91.254192.137.91.255510
175192.137.92.0/23192.137.92.1 to 192.137.93.254192.137.93.255510
176192.137.94.0/23192.137.94.1 to 192.137.95.254192.137.95.255510
177192.137.96.0/23192.137.96.1 to 192.137.97.254192.137.97.255510
178192.137.98.0/23192.137.98.1 to 192.137.99.254192.137.99.255510
179192.137.100.0/23192.137.100.1 to 192.137.101.254192.137.101.255510
180192.137.102.0/23192.137.102.1 to 192.137.103.254192.137.103.255510
181192.137.104.0/23192.137.104.1 to 192.137.105.254192.137.105.255510
182192.137.106.0/23192.137.106.1 to 192.137.107.254192.137.107.255510
183192.137.108.0/23192.137.108.1 to 192.137.109.254192.137.109.255510
184192.137.110.0/23192.137.110.1 to 192.137.111.254192.137.111.255510
185192.137.112.0/23192.137.112.1 to 192.137.113.254192.137.113.255510
186192.137.114.0/23192.137.114.1 to 192.137.115.254192.137.115.255510
187192.137.116.0/23192.137.116.1 to 192.137.117.254192.137.117.255510
188192.137.118.0/23192.137.118.1 to 192.137.119.254192.137.119.255510
189192.137.120.0/23192.137.120.1 to 192.137.121.254192.137.121.255510
190192.137.122.0/23192.137.122.1 to 192.137.123.254192.137.123.255510
191192.137.124.0/23192.137.124.1 to 192.137.125.254192.137.125.255510
192192.137.126.0/23192.137.126.1 to 192.137.127.254192.137.127.255510
193192.137.128.0/23192.137.128.1 to 192.137.129.254192.137.129.255510
194192.137.130.0/23192.137.130.1 to 192.137.131.254192.137.131.255510
195192.137.132.0/23192.137.132.1 to 192.137.133.254192.137.133.255510
196192.137.134.0/23192.137.134.1 to 192.137.135.254192.137.135.255510
197192.137.136.0/23192.137.136.1 to 192.137.137.254192.137.137.255510
198192.137.138.0/23192.137.138.1 to 192.137.139.254192.137.139.255510
199192.137.140.0/23192.137.140.1 to 192.137.141.254192.137.141.255510
200192.137.142.0/23192.137.142.1 to 192.137.143.254192.137.143.255510
201192.137.144.0/23192.137.144.1 to 192.137.145.254192.137.145.255510
202192.137.146.0/23192.137.146.1 to 192.137.147.254192.137.147.255510
203192.137.148.0/23192.137.148.1 to 192.137.149.254192.137.149.255510
204192.137.150.0/23192.137.150.1 to 192.137.151.254192.137.151.255510
205192.137.152.0/23192.137.152.1 to 192.137.153.254192.137.153.255510
206192.137.154.0/23192.137.154.1 to 192.137.155.254192.137.155.255510
207192.137.156.0/23192.137.156.1 to 192.137.157.254192.137.157.255510
208192.137.158.0/23192.137.158.1 to 192.137.159.254192.137.159.255510
209192.137.160.0/23192.137.160.1 to 192.137.161.254192.137.161.255510
210192.137.162.0/23192.137.162.1 to 192.137.163.254192.137.163.255510
211192.137.164.0/23192.137.164.1 to 192.137.165.254192.137.165.255510
212192.137.166.0/23192.137.166.1 to 192.137.167.254192.137.167.255510
213192.137.168.0/23192.137.168.1 to 192.137.169.254192.137.169.255510
214192.137.170.0/23192.137.170.1 to 192.137.171.254192.137.171.255510
215192.137.172.0/23192.137.172.1 to 192.137.173.254192.137.173.255510
216192.137.174.0/23192.137.174.1 to 192.137.175.254192.137.175.255510
217192.137.176.0/23192.137.176.1 to 192.137.177.254192.137.177.255510
218192.137.178.0/23192.137.178.1 to 192.137.179.254192.137.179.255510
219192.137.180.0/23192.137.180.1 to 192.137.181.254192.137.181.255510
220192.137.182.0/23192.137.182.1 to 192.137.183.254192.137.183.255510
221192.137.184.0/23192.137.184.1 to 192.137.185.254192.137.185.255510
222192.137.186.0/23192.137.186.1 to 192.137.187.254192.137.187.255510
223192.137.188.0/23192.137.188.1 to 192.137.189.254192.137.189.255510
224192.137.190.0/23192.137.190.1 to 192.137.191.254192.137.191.255510
225192.137.192.0/23192.137.192.1 to 192.137.193.254192.137.193.255510
226192.137.194.0/23192.137.194.1 to 192.137.195.254192.137.195.255510
227192.137.196.0/23192.137.196.1 to 192.137.197.254192.137.197.255510
228192.137.198.0/23192.137.198.1 to 192.137.199.254192.137.199.255510
229192.137.200.0/23192.137.200.1 to 192.137.201.254192.137.201.255510
230192.137.202.0/23192.137.202.1 to 192.137.203.254192.137.203.255510
231192.137.204.0/23192.137.204.1 to 192.137.205.254192.137.205.255510
232192.137.206.0/23192.137.206.1 to 192.137.207.254192.137.207.255510
233192.137.208.0/23192.137.208.1 to 192.137.209.254192.137.209.255510
234192.137.210.0/23192.137.210.1 to 192.137.211.254192.137.211.255510
235192.137.212.0/23192.137.212.1 to 192.137.213.254192.137.213.255510
236192.137.214.0/23192.137.214.1 to 192.137.215.254192.137.215.255510
237192.137.216.0/23192.137.216.1 to 192.137.217.254192.137.217.255510
238192.137.218.0/23192.137.218.1 to 192.137.219.254192.137.219.255510
239192.137.220.0/23192.137.220.1 to 192.137.221.254192.137.221.255510
240192.137.222.0/23192.137.222.1 to 192.137.223.254192.137.223.255510
241192.137.224.0/23192.137.224.1 to 192.137.225.254192.137.225.255510
242192.137.226.0/23192.137.226.1 to 192.137.227.254192.137.227.255510
243192.137.228.0/23192.137.228.1 to 192.137.229.254192.137.229.255510
244192.137.230.0/23192.137.230.1 to 192.137.231.254192.137.231.255510
245192.137.232.0/23192.137.232.1 to 192.137.233.254192.137.233.255510
246192.137.234.0/23192.137.234.1 to 192.137.235.254192.137.235.255510
247192.137.236.0/23192.137.236.1 to 192.137.237.254192.137.237.255510
248192.137.238.0/23192.137.238.1 to 192.137.239.254192.137.239.255510
249192.137.240.0/23192.137.240.1 to 192.137.241.254192.137.241.255510
250192.137.242.0/23192.137.242.1 to 192.137.243.254192.137.243.255510
251192.137.244.0/23192.137.244.1 to 192.137.245.254192.137.245.255510
252192.137.246.0/23192.137.246.1 to 192.137.247.254192.137.247.255510
253192.137.248.0/23192.137.248.1 to 192.137.249.254192.137.249.255510
254192.137.250.0/23192.137.250.1 to 192.137.251.254192.137.251.255510
255192.137.252.0/23192.137.252.1 to 192.137.253.254192.137.253.255510
256192.137.254.0/23192.137.254.1 to 192.137.255.254192.137.255.255510

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.