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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.

Network102.136.0.0/13
Usable hosts524,286
Subnet mask255.248.0.0
Addresses524,288
Network address
102.136.0.0
Broadcast address
102.143.255.255
First usable
102.136.0.1
Last usable
102.143.255.254
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
A (default /8)
As numbers
Hex 66880000 · Integer 1720188928 to 1720713215
Reverse DNS zones
136.102.in-addr.arpa
137.102.in-addr.arpa
138.102.in-addr.arpa
139.102.in-addr.arpa
140.102.in-addr.arpa
141.102.in-addr.arpa
142.102.in-addr.arpa
143.102.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
Address01100110.10001000.00000000.00000000102.136.0.0
Subnet mask11111111.11111000.00000000.00000000255.248.0.0
Network01100110.10001000.00000000.00000000102.136.0.0
Broadcast01100110.10001111.11111111.11111111102.143.255.255
Split into smaller subnets/24
/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)

102.136.0.0/13 makes 2,048 subnets of /24; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1102.136.0.0/24102.136.0.1 to 102.136.0.254102.136.0.255254
2102.136.1.0/24102.136.1.1 to 102.136.1.254102.136.1.255254
3102.136.2.0/24102.136.2.1 to 102.136.2.254102.136.2.255254
4102.136.3.0/24102.136.3.1 to 102.136.3.254102.136.3.255254
5102.136.4.0/24102.136.4.1 to 102.136.4.254102.136.4.255254
6102.136.5.0/24102.136.5.1 to 102.136.5.254102.136.5.255254
7102.136.6.0/24102.136.6.1 to 102.136.6.254102.136.6.255254
8102.136.7.0/24102.136.7.1 to 102.136.7.254102.136.7.255254
9102.136.8.0/24102.136.8.1 to 102.136.8.254102.136.8.255254
10102.136.9.0/24102.136.9.1 to 102.136.9.254102.136.9.255254
11102.136.10.0/24102.136.10.1 to 102.136.10.254102.136.10.255254
12102.136.11.0/24102.136.11.1 to 102.136.11.254102.136.11.255254
13102.136.12.0/24102.136.12.1 to 102.136.12.254102.136.12.255254
14102.136.13.0/24102.136.13.1 to 102.136.13.254102.136.13.255254
15102.136.14.0/24102.136.14.1 to 102.136.14.254102.136.14.255254
16102.136.15.0/24102.136.15.1 to 102.136.15.254102.136.15.255254
17102.136.16.0/24102.136.16.1 to 102.136.16.254102.136.16.255254
18102.136.17.0/24102.136.17.1 to 102.136.17.254102.136.17.255254
19102.136.18.0/24102.136.18.1 to 102.136.18.254102.136.18.255254
20102.136.19.0/24102.136.19.1 to 102.136.19.254102.136.19.255254
21102.136.20.0/24102.136.20.1 to 102.136.20.254102.136.20.255254
22102.136.21.0/24102.136.21.1 to 102.136.21.254102.136.21.255254
23102.136.22.0/24102.136.22.1 to 102.136.22.254102.136.22.255254
24102.136.23.0/24102.136.23.1 to 102.136.23.254102.136.23.255254
25102.136.24.0/24102.136.24.1 to 102.136.24.254102.136.24.255254
26102.136.25.0/24102.136.25.1 to 102.136.25.254102.136.25.255254
27102.136.26.0/24102.136.26.1 to 102.136.26.254102.136.26.255254
28102.136.27.0/24102.136.27.1 to 102.136.27.254102.136.27.255254
29102.136.28.0/24102.136.28.1 to 102.136.28.254102.136.28.255254
30102.136.29.0/24102.136.29.1 to 102.136.29.254102.136.29.255254
31102.136.30.0/24102.136.30.1 to 102.136.30.254102.136.30.255254
32102.136.31.0/24102.136.31.1 to 102.136.31.254102.136.31.255254
33102.136.32.0/24102.136.32.1 to 102.136.32.254102.136.32.255254
34102.136.33.0/24102.136.33.1 to 102.136.33.254102.136.33.255254
35102.136.34.0/24102.136.34.1 to 102.136.34.254102.136.34.255254
36102.136.35.0/24102.136.35.1 to 102.136.35.254102.136.35.255254
37102.136.36.0/24102.136.36.1 to 102.136.36.254102.136.36.255254
38102.136.37.0/24102.136.37.1 to 102.136.37.254102.136.37.255254
39102.136.38.0/24102.136.38.1 to 102.136.38.254102.136.38.255254
40102.136.39.0/24102.136.39.1 to 102.136.39.254102.136.39.255254
41102.136.40.0/24102.136.40.1 to 102.136.40.254102.136.40.255254
42102.136.41.0/24102.136.41.1 to 102.136.41.254102.136.41.255254
43102.136.42.0/24102.136.42.1 to 102.136.42.254102.136.42.255254
44102.136.43.0/24102.136.43.1 to 102.136.43.254102.136.43.255254
45102.136.44.0/24102.136.44.1 to 102.136.44.254102.136.44.255254
46102.136.45.0/24102.136.45.1 to 102.136.45.254102.136.45.255254
47102.136.46.0/24102.136.46.1 to 102.136.46.254102.136.46.255254
48102.136.47.0/24102.136.47.1 to 102.136.47.254102.136.47.255254
49102.136.48.0/24102.136.48.1 to 102.136.48.254102.136.48.255254
50102.136.49.0/24102.136.49.1 to 102.136.49.254102.136.49.255254
51102.136.50.0/24102.136.50.1 to 102.136.50.254102.136.50.255254
52102.136.51.0/24102.136.51.1 to 102.136.51.254102.136.51.255254
53102.136.52.0/24102.136.52.1 to 102.136.52.254102.136.52.255254
54102.136.53.0/24102.136.53.1 to 102.136.53.254102.136.53.255254
55102.136.54.0/24102.136.54.1 to 102.136.54.254102.136.54.255254
56102.136.55.0/24102.136.55.1 to 102.136.55.254102.136.55.255254
57102.136.56.0/24102.136.56.1 to 102.136.56.254102.136.56.255254
58102.136.57.0/24102.136.57.1 to 102.136.57.254102.136.57.255254
59102.136.58.0/24102.136.58.1 to 102.136.58.254102.136.58.255254
60102.136.59.0/24102.136.59.1 to 102.136.59.254102.136.59.255254
61102.136.60.0/24102.136.60.1 to 102.136.60.254102.136.60.255254
62102.136.61.0/24102.136.61.1 to 102.136.61.254102.136.61.255254
63102.136.62.0/24102.136.62.1 to 102.136.62.254102.136.62.255254
64102.136.63.0/24102.136.63.1 to 102.136.63.254102.136.63.255254
65102.136.64.0/24102.136.64.1 to 102.136.64.254102.136.64.255254
66102.136.65.0/24102.136.65.1 to 102.136.65.254102.136.65.255254
67102.136.66.0/24102.136.66.1 to 102.136.66.254102.136.66.255254
68102.136.67.0/24102.136.67.1 to 102.136.67.254102.136.67.255254
69102.136.68.0/24102.136.68.1 to 102.136.68.254102.136.68.255254
70102.136.69.0/24102.136.69.1 to 102.136.69.254102.136.69.255254
71102.136.70.0/24102.136.70.1 to 102.136.70.254102.136.70.255254
72102.136.71.0/24102.136.71.1 to 102.136.71.254102.136.71.255254
73102.136.72.0/24102.136.72.1 to 102.136.72.254102.136.72.255254
74102.136.73.0/24102.136.73.1 to 102.136.73.254102.136.73.255254
75102.136.74.0/24102.136.74.1 to 102.136.74.254102.136.74.255254
76102.136.75.0/24102.136.75.1 to 102.136.75.254102.136.75.255254
77102.136.76.0/24102.136.76.1 to 102.136.76.254102.136.76.255254
78102.136.77.0/24102.136.77.1 to 102.136.77.254102.136.77.255254
79102.136.78.0/24102.136.78.1 to 102.136.78.254102.136.78.255254
80102.136.79.0/24102.136.79.1 to 102.136.79.254102.136.79.255254
81102.136.80.0/24102.136.80.1 to 102.136.80.254102.136.80.255254
82102.136.81.0/24102.136.81.1 to 102.136.81.254102.136.81.255254
83102.136.82.0/24102.136.82.1 to 102.136.82.254102.136.82.255254
84102.136.83.0/24102.136.83.1 to 102.136.83.254102.136.83.255254
85102.136.84.0/24102.136.84.1 to 102.136.84.254102.136.84.255254
86102.136.85.0/24102.136.85.1 to 102.136.85.254102.136.85.255254
87102.136.86.0/24102.136.86.1 to 102.136.86.254102.136.86.255254
88102.136.87.0/24102.136.87.1 to 102.136.87.254102.136.87.255254
89102.136.88.0/24102.136.88.1 to 102.136.88.254102.136.88.255254
90102.136.89.0/24102.136.89.1 to 102.136.89.254102.136.89.255254
91102.136.90.0/24102.136.90.1 to 102.136.90.254102.136.90.255254
92102.136.91.0/24102.136.91.1 to 102.136.91.254102.136.91.255254
93102.136.92.0/24102.136.92.1 to 102.136.92.254102.136.92.255254
94102.136.93.0/24102.136.93.1 to 102.136.93.254102.136.93.255254
95102.136.94.0/24102.136.94.1 to 102.136.94.254102.136.94.255254
96102.136.95.0/24102.136.95.1 to 102.136.95.254102.136.95.255254
97102.136.96.0/24102.136.96.1 to 102.136.96.254102.136.96.255254
98102.136.97.0/24102.136.97.1 to 102.136.97.254102.136.97.255254
99102.136.98.0/24102.136.98.1 to 102.136.98.254102.136.98.255254
100102.136.99.0/24102.136.99.1 to 102.136.99.254102.136.99.255254
101102.136.100.0/24102.136.100.1 to 102.136.100.254102.136.100.255254
102102.136.101.0/24102.136.101.1 to 102.136.101.254102.136.101.255254
103102.136.102.0/24102.136.102.1 to 102.136.102.254102.136.102.255254
104102.136.103.0/24102.136.103.1 to 102.136.103.254102.136.103.255254
105102.136.104.0/24102.136.104.1 to 102.136.104.254102.136.104.255254
106102.136.105.0/24102.136.105.1 to 102.136.105.254102.136.105.255254
107102.136.106.0/24102.136.106.1 to 102.136.106.254102.136.106.255254
108102.136.107.0/24102.136.107.1 to 102.136.107.254102.136.107.255254
109102.136.108.0/24102.136.108.1 to 102.136.108.254102.136.108.255254
110102.136.109.0/24102.136.109.1 to 102.136.109.254102.136.109.255254
111102.136.110.0/24102.136.110.1 to 102.136.110.254102.136.110.255254
112102.136.111.0/24102.136.111.1 to 102.136.111.254102.136.111.255254
113102.136.112.0/24102.136.112.1 to 102.136.112.254102.136.112.255254
114102.136.113.0/24102.136.113.1 to 102.136.113.254102.136.113.255254
115102.136.114.0/24102.136.114.1 to 102.136.114.254102.136.114.255254
116102.136.115.0/24102.136.115.1 to 102.136.115.254102.136.115.255254
117102.136.116.0/24102.136.116.1 to 102.136.116.254102.136.116.255254
118102.136.117.0/24102.136.117.1 to 102.136.117.254102.136.117.255254
119102.136.118.0/24102.136.118.1 to 102.136.118.254102.136.118.255254
120102.136.119.0/24102.136.119.1 to 102.136.119.254102.136.119.255254
121102.136.120.0/24102.136.120.1 to 102.136.120.254102.136.120.255254
122102.136.121.0/24102.136.121.1 to 102.136.121.254102.136.121.255254
123102.136.122.0/24102.136.122.1 to 102.136.122.254102.136.122.255254
124102.136.123.0/24102.136.123.1 to 102.136.123.254102.136.123.255254
125102.136.124.0/24102.136.124.1 to 102.136.124.254102.136.124.255254
126102.136.125.0/24102.136.125.1 to 102.136.125.254102.136.125.255254
127102.136.126.0/24102.136.126.1 to 102.136.126.254102.136.126.255254
128102.136.127.0/24102.136.127.1 to 102.136.127.254102.136.127.255254
129102.136.128.0/24102.136.128.1 to 102.136.128.254102.136.128.255254
130102.136.129.0/24102.136.129.1 to 102.136.129.254102.136.129.255254
131102.136.130.0/24102.136.130.1 to 102.136.130.254102.136.130.255254
132102.136.131.0/24102.136.131.1 to 102.136.131.254102.136.131.255254
133102.136.132.0/24102.136.132.1 to 102.136.132.254102.136.132.255254
134102.136.133.0/24102.136.133.1 to 102.136.133.254102.136.133.255254
135102.136.134.0/24102.136.134.1 to 102.136.134.254102.136.134.255254
136102.136.135.0/24102.136.135.1 to 102.136.135.254102.136.135.255254
137102.136.136.0/24102.136.136.1 to 102.136.136.254102.136.136.255254
138102.136.137.0/24102.136.137.1 to 102.136.137.254102.136.137.255254
139102.136.138.0/24102.136.138.1 to 102.136.138.254102.136.138.255254
140102.136.139.0/24102.136.139.1 to 102.136.139.254102.136.139.255254
141102.136.140.0/24102.136.140.1 to 102.136.140.254102.136.140.255254
142102.136.141.0/24102.136.141.1 to 102.136.141.254102.136.141.255254
143102.136.142.0/24102.136.142.1 to 102.136.142.254102.136.142.255254
144102.136.143.0/24102.136.143.1 to 102.136.143.254102.136.143.255254
145102.136.144.0/24102.136.144.1 to 102.136.144.254102.136.144.255254
146102.136.145.0/24102.136.145.1 to 102.136.145.254102.136.145.255254
147102.136.146.0/24102.136.146.1 to 102.136.146.254102.136.146.255254
148102.136.147.0/24102.136.147.1 to 102.136.147.254102.136.147.255254
149102.136.148.0/24102.136.148.1 to 102.136.148.254102.136.148.255254
150102.136.149.0/24102.136.149.1 to 102.136.149.254102.136.149.255254
151102.136.150.0/24102.136.150.1 to 102.136.150.254102.136.150.255254
152102.136.151.0/24102.136.151.1 to 102.136.151.254102.136.151.255254
153102.136.152.0/24102.136.152.1 to 102.136.152.254102.136.152.255254
154102.136.153.0/24102.136.153.1 to 102.136.153.254102.136.153.255254
155102.136.154.0/24102.136.154.1 to 102.136.154.254102.136.154.255254
156102.136.155.0/24102.136.155.1 to 102.136.155.254102.136.155.255254
157102.136.156.0/24102.136.156.1 to 102.136.156.254102.136.156.255254
158102.136.157.0/24102.136.157.1 to 102.136.157.254102.136.157.255254
159102.136.158.0/24102.136.158.1 to 102.136.158.254102.136.158.255254
160102.136.159.0/24102.136.159.1 to 102.136.159.254102.136.159.255254
161102.136.160.0/24102.136.160.1 to 102.136.160.254102.136.160.255254
162102.136.161.0/24102.136.161.1 to 102.136.161.254102.136.161.255254
163102.136.162.0/24102.136.162.1 to 102.136.162.254102.136.162.255254
164102.136.163.0/24102.136.163.1 to 102.136.163.254102.136.163.255254
165102.136.164.0/24102.136.164.1 to 102.136.164.254102.136.164.255254
166102.136.165.0/24102.136.165.1 to 102.136.165.254102.136.165.255254
167102.136.166.0/24102.136.166.1 to 102.136.166.254102.136.166.255254
168102.136.167.0/24102.136.167.1 to 102.136.167.254102.136.167.255254
169102.136.168.0/24102.136.168.1 to 102.136.168.254102.136.168.255254
170102.136.169.0/24102.136.169.1 to 102.136.169.254102.136.169.255254
171102.136.170.0/24102.136.170.1 to 102.136.170.254102.136.170.255254
172102.136.171.0/24102.136.171.1 to 102.136.171.254102.136.171.255254
173102.136.172.0/24102.136.172.1 to 102.136.172.254102.136.172.255254
174102.136.173.0/24102.136.173.1 to 102.136.173.254102.136.173.255254
175102.136.174.0/24102.136.174.1 to 102.136.174.254102.136.174.255254
176102.136.175.0/24102.136.175.1 to 102.136.175.254102.136.175.255254
177102.136.176.0/24102.136.176.1 to 102.136.176.254102.136.176.255254
178102.136.177.0/24102.136.177.1 to 102.136.177.254102.136.177.255254
179102.136.178.0/24102.136.178.1 to 102.136.178.254102.136.178.255254
180102.136.179.0/24102.136.179.1 to 102.136.179.254102.136.179.255254
181102.136.180.0/24102.136.180.1 to 102.136.180.254102.136.180.255254
182102.136.181.0/24102.136.181.1 to 102.136.181.254102.136.181.255254
183102.136.182.0/24102.136.182.1 to 102.136.182.254102.136.182.255254
184102.136.183.0/24102.136.183.1 to 102.136.183.254102.136.183.255254
185102.136.184.0/24102.136.184.1 to 102.136.184.254102.136.184.255254
186102.136.185.0/24102.136.185.1 to 102.136.185.254102.136.185.255254
187102.136.186.0/24102.136.186.1 to 102.136.186.254102.136.186.255254
188102.136.187.0/24102.136.187.1 to 102.136.187.254102.136.187.255254
189102.136.188.0/24102.136.188.1 to 102.136.188.254102.136.188.255254
190102.136.189.0/24102.136.189.1 to 102.136.189.254102.136.189.255254
191102.136.190.0/24102.136.190.1 to 102.136.190.254102.136.190.255254
192102.136.191.0/24102.136.191.1 to 102.136.191.254102.136.191.255254
193102.136.192.0/24102.136.192.1 to 102.136.192.254102.136.192.255254
194102.136.193.0/24102.136.193.1 to 102.136.193.254102.136.193.255254
195102.136.194.0/24102.136.194.1 to 102.136.194.254102.136.194.255254
196102.136.195.0/24102.136.195.1 to 102.136.195.254102.136.195.255254
197102.136.196.0/24102.136.196.1 to 102.136.196.254102.136.196.255254
198102.136.197.0/24102.136.197.1 to 102.136.197.254102.136.197.255254
199102.136.198.0/24102.136.198.1 to 102.136.198.254102.136.198.255254
200102.136.199.0/24102.136.199.1 to 102.136.199.254102.136.199.255254
201102.136.200.0/24102.136.200.1 to 102.136.200.254102.136.200.255254
202102.136.201.0/24102.136.201.1 to 102.136.201.254102.136.201.255254
203102.136.202.0/24102.136.202.1 to 102.136.202.254102.136.202.255254
204102.136.203.0/24102.136.203.1 to 102.136.203.254102.136.203.255254
205102.136.204.0/24102.136.204.1 to 102.136.204.254102.136.204.255254
206102.136.205.0/24102.136.205.1 to 102.136.205.254102.136.205.255254
207102.136.206.0/24102.136.206.1 to 102.136.206.254102.136.206.255254
208102.136.207.0/24102.136.207.1 to 102.136.207.254102.136.207.255254
209102.136.208.0/24102.136.208.1 to 102.136.208.254102.136.208.255254
210102.136.209.0/24102.136.209.1 to 102.136.209.254102.136.209.255254
211102.136.210.0/24102.136.210.1 to 102.136.210.254102.136.210.255254
212102.136.211.0/24102.136.211.1 to 102.136.211.254102.136.211.255254
213102.136.212.0/24102.136.212.1 to 102.136.212.254102.136.212.255254
214102.136.213.0/24102.136.213.1 to 102.136.213.254102.136.213.255254
215102.136.214.0/24102.136.214.1 to 102.136.214.254102.136.214.255254
216102.136.215.0/24102.136.215.1 to 102.136.215.254102.136.215.255254
217102.136.216.0/24102.136.216.1 to 102.136.216.254102.136.216.255254
218102.136.217.0/24102.136.217.1 to 102.136.217.254102.136.217.255254
219102.136.218.0/24102.136.218.1 to 102.136.218.254102.136.218.255254
220102.136.219.0/24102.136.219.1 to 102.136.219.254102.136.219.255254
221102.136.220.0/24102.136.220.1 to 102.136.220.254102.136.220.255254
222102.136.221.0/24102.136.221.1 to 102.136.221.254102.136.221.255254
223102.136.222.0/24102.136.222.1 to 102.136.222.254102.136.222.255254
224102.136.223.0/24102.136.223.1 to 102.136.223.254102.136.223.255254
225102.136.224.0/24102.136.224.1 to 102.136.224.254102.136.224.255254
226102.136.225.0/24102.136.225.1 to 102.136.225.254102.136.225.255254
227102.136.226.0/24102.136.226.1 to 102.136.226.254102.136.226.255254
228102.136.227.0/24102.136.227.1 to 102.136.227.254102.136.227.255254
229102.136.228.0/24102.136.228.1 to 102.136.228.254102.136.228.255254
230102.136.229.0/24102.136.229.1 to 102.136.229.254102.136.229.255254
231102.136.230.0/24102.136.230.1 to 102.136.230.254102.136.230.255254
232102.136.231.0/24102.136.231.1 to 102.136.231.254102.136.231.255254
233102.136.232.0/24102.136.232.1 to 102.136.232.254102.136.232.255254
234102.136.233.0/24102.136.233.1 to 102.136.233.254102.136.233.255254
235102.136.234.0/24102.136.234.1 to 102.136.234.254102.136.234.255254
236102.136.235.0/24102.136.235.1 to 102.136.235.254102.136.235.255254
237102.136.236.0/24102.136.236.1 to 102.136.236.254102.136.236.255254
238102.136.237.0/24102.136.237.1 to 102.136.237.254102.136.237.255254
239102.136.238.0/24102.136.238.1 to 102.136.238.254102.136.238.255254
240102.136.239.0/24102.136.239.1 to 102.136.239.254102.136.239.255254
241102.136.240.0/24102.136.240.1 to 102.136.240.254102.136.240.255254
242102.136.241.0/24102.136.241.1 to 102.136.241.254102.136.241.255254
243102.136.242.0/24102.136.242.1 to 102.136.242.254102.136.242.255254
244102.136.243.0/24102.136.243.1 to 102.136.243.254102.136.243.255254
245102.136.244.0/24102.136.244.1 to 102.136.244.254102.136.244.255254
246102.136.245.0/24102.136.245.1 to 102.136.245.254102.136.245.255254
247102.136.246.0/24102.136.246.1 to 102.136.246.254102.136.246.255254
248102.136.247.0/24102.136.247.1 to 102.136.247.254102.136.247.255254
249102.136.248.0/24102.136.248.1 to 102.136.248.254102.136.248.255254
250102.136.249.0/24102.136.249.1 to 102.136.249.254102.136.249.255254
251102.136.250.0/24102.136.250.1 to 102.136.250.254102.136.250.255254
252102.136.251.0/24102.136.251.1 to 102.136.251.254102.136.251.255254
253102.136.252.0/24102.136.252.1 to 102.136.252.254102.136.252.255254
254102.136.253.0/24102.136.253.1 to 102.136.253.254102.136.253.255254
255102.136.254.0/24102.136.254.1 to 102.136.254.254102.136.254.255254
256102.136.255.0/24102.136.255.1 to 102.136.255.254102.136.255.255254

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.