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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.

Network113.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
113.0.0.0
Broadcast address
113.255.255.255
First usable
113.0.0.1
Last usable
113.255.255.254
Usable hosts
16,777,214 (16,777,216 less the network and broadcast addresses)
Subnet mask
255.0.0.0
Wildcard mask
0.255.255.255 (Cisco ACLs, OSPF)
Prefix length
/8
Type
Public public
Old class
A (default /8)
As numbers
Hex 71000000 · Integer 1895825408 to 1912602623
Reverse DNS zone
113.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110001..00000000.00000000.00000000113.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01110001..00000000.00000000.00000000113.0.0.0
Broadcast01110001..11111111.11111111.11111111113.255.255.255
Split into smaller subnets/16
/9 (2)/10 (4)/11 (8)/12 (16)/13 (32)/14 (64)/15 (128)/16 (256)/17 (512)/18 (1,024)/19 (2,048)/20 (4,096)

113.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1113.0.0.0/16113.0.0.1 to 113.0.255.254113.0.255.25565,534
2113.1.0.0/16113.1.0.1 to 113.1.255.254113.1.255.25565,534
3113.2.0.0/16113.2.0.1 to 113.2.255.254113.2.255.25565,534
4113.3.0.0/16113.3.0.1 to 113.3.255.254113.3.255.25565,534
5113.4.0.0/16113.4.0.1 to 113.4.255.254113.4.255.25565,534
6113.5.0.0/16113.5.0.1 to 113.5.255.254113.5.255.25565,534
7113.6.0.0/16113.6.0.1 to 113.6.255.254113.6.255.25565,534
8113.7.0.0/16113.7.0.1 to 113.7.255.254113.7.255.25565,534
9113.8.0.0/16113.8.0.1 to 113.8.255.254113.8.255.25565,534
10113.9.0.0/16113.9.0.1 to 113.9.255.254113.9.255.25565,534
11113.10.0.0/16113.10.0.1 to 113.10.255.254113.10.255.25565,534
12113.11.0.0/16113.11.0.1 to 113.11.255.254113.11.255.25565,534
13113.12.0.0/16113.12.0.1 to 113.12.255.254113.12.255.25565,534
14113.13.0.0/16113.13.0.1 to 113.13.255.254113.13.255.25565,534
15113.14.0.0/16113.14.0.1 to 113.14.255.254113.14.255.25565,534
16113.15.0.0/16113.15.0.1 to 113.15.255.254113.15.255.25565,534
17113.16.0.0/16113.16.0.1 to 113.16.255.254113.16.255.25565,534
18113.17.0.0/16113.17.0.1 to 113.17.255.254113.17.255.25565,534
19113.18.0.0/16113.18.0.1 to 113.18.255.254113.18.255.25565,534
20113.19.0.0/16113.19.0.1 to 113.19.255.254113.19.255.25565,534
21113.20.0.0/16113.20.0.1 to 113.20.255.254113.20.255.25565,534
22113.21.0.0/16113.21.0.1 to 113.21.255.254113.21.255.25565,534
23113.22.0.0/16113.22.0.1 to 113.22.255.254113.22.255.25565,534
24113.23.0.0/16113.23.0.1 to 113.23.255.254113.23.255.25565,534
25113.24.0.0/16113.24.0.1 to 113.24.255.254113.24.255.25565,534
26113.25.0.0/16113.25.0.1 to 113.25.255.254113.25.255.25565,534
27113.26.0.0/16113.26.0.1 to 113.26.255.254113.26.255.25565,534
28113.27.0.0/16113.27.0.1 to 113.27.255.254113.27.255.25565,534
29113.28.0.0/16113.28.0.1 to 113.28.255.254113.28.255.25565,534
30113.29.0.0/16113.29.0.1 to 113.29.255.254113.29.255.25565,534
31113.30.0.0/16113.30.0.1 to 113.30.255.254113.30.255.25565,534
32113.31.0.0/16113.31.0.1 to 113.31.255.254113.31.255.25565,534
33113.32.0.0/16113.32.0.1 to 113.32.255.254113.32.255.25565,534
34113.33.0.0/16113.33.0.1 to 113.33.255.254113.33.255.25565,534
35113.34.0.0/16113.34.0.1 to 113.34.255.254113.34.255.25565,534
36113.35.0.0/16113.35.0.1 to 113.35.255.254113.35.255.25565,534
37113.36.0.0/16113.36.0.1 to 113.36.255.254113.36.255.25565,534
38113.37.0.0/16113.37.0.1 to 113.37.255.254113.37.255.25565,534
39113.38.0.0/16113.38.0.1 to 113.38.255.254113.38.255.25565,534
40113.39.0.0/16113.39.0.1 to 113.39.255.254113.39.255.25565,534
41113.40.0.0/16113.40.0.1 to 113.40.255.254113.40.255.25565,534
42113.41.0.0/16113.41.0.1 to 113.41.255.254113.41.255.25565,534
43113.42.0.0/16113.42.0.1 to 113.42.255.254113.42.255.25565,534
44113.43.0.0/16113.43.0.1 to 113.43.255.254113.43.255.25565,534
45113.44.0.0/16113.44.0.1 to 113.44.255.254113.44.255.25565,534
46113.45.0.0/16113.45.0.1 to 113.45.255.254113.45.255.25565,534
47113.46.0.0/16113.46.0.1 to 113.46.255.254113.46.255.25565,534
48113.47.0.0/16113.47.0.1 to 113.47.255.254113.47.255.25565,534
49113.48.0.0/16113.48.0.1 to 113.48.255.254113.48.255.25565,534
50113.49.0.0/16113.49.0.1 to 113.49.255.254113.49.255.25565,534
51113.50.0.0/16113.50.0.1 to 113.50.255.254113.50.255.25565,534
52113.51.0.0/16113.51.0.1 to 113.51.255.254113.51.255.25565,534
53113.52.0.0/16113.52.0.1 to 113.52.255.254113.52.255.25565,534
54113.53.0.0/16113.53.0.1 to 113.53.255.254113.53.255.25565,534
55113.54.0.0/16113.54.0.1 to 113.54.255.254113.54.255.25565,534
56113.55.0.0/16113.55.0.1 to 113.55.255.254113.55.255.25565,534
57113.56.0.0/16113.56.0.1 to 113.56.255.254113.56.255.25565,534
58113.57.0.0/16113.57.0.1 to 113.57.255.254113.57.255.25565,534
59113.58.0.0/16113.58.0.1 to 113.58.255.254113.58.255.25565,534
60113.59.0.0/16113.59.0.1 to 113.59.255.254113.59.255.25565,534
61113.60.0.0/16113.60.0.1 to 113.60.255.254113.60.255.25565,534
62113.61.0.0/16113.61.0.1 to 113.61.255.254113.61.255.25565,534
63113.62.0.0/16113.62.0.1 to 113.62.255.254113.62.255.25565,534
64113.63.0.0/16113.63.0.1 to 113.63.255.254113.63.255.25565,534
65113.64.0.0/16113.64.0.1 to 113.64.255.254113.64.255.25565,534
66113.65.0.0/16113.65.0.1 to 113.65.255.254113.65.255.25565,534
67113.66.0.0/16113.66.0.1 to 113.66.255.254113.66.255.25565,534
68113.67.0.0/16113.67.0.1 to 113.67.255.254113.67.255.25565,534
69113.68.0.0/16113.68.0.1 to 113.68.255.254113.68.255.25565,534
70113.69.0.0/16113.69.0.1 to 113.69.255.254113.69.255.25565,534
71113.70.0.0/16113.70.0.1 to 113.70.255.254113.70.255.25565,534
72113.71.0.0/16113.71.0.1 to 113.71.255.254113.71.255.25565,534
73113.72.0.0/16113.72.0.1 to 113.72.255.254113.72.255.25565,534
74113.73.0.0/16113.73.0.1 to 113.73.255.254113.73.255.25565,534
75113.74.0.0/16113.74.0.1 to 113.74.255.254113.74.255.25565,534
76113.75.0.0/16113.75.0.1 to 113.75.255.254113.75.255.25565,534
77113.76.0.0/16113.76.0.1 to 113.76.255.254113.76.255.25565,534
78113.77.0.0/16113.77.0.1 to 113.77.255.254113.77.255.25565,534
79113.78.0.0/16113.78.0.1 to 113.78.255.254113.78.255.25565,534
80113.79.0.0/16113.79.0.1 to 113.79.255.254113.79.255.25565,534
81113.80.0.0/16113.80.0.1 to 113.80.255.254113.80.255.25565,534
82113.81.0.0/16113.81.0.1 to 113.81.255.254113.81.255.25565,534
83113.82.0.0/16113.82.0.1 to 113.82.255.254113.82.255.25565,534
84113.83.0.0/16113.83.0.1 to 113.83.255.254113.83.255.25565,534
85113.84.0.0/16113.84.0.1 to 113.84.255.254113.84.255.25565,534
86113.85.0.0/16113.85.0.1 to 113.85.255.254113.85.255.25565,534
87113.86.0.0/16113.86.0.1 to 113.86.255.254113.86.255.25565,534
88113.87.0.0/16113.87.0.1 to 113.87.255.254113.87.255.25565,534
89113.88.0.0/16113.88.0.1 to 113.88.255.254113.88.255.25565,534
90113.89.0.0/16113.89.0.1 to 113.89.255.254113.89.255.25565,534
91113.90.0.0/16113.90.0.1 to 113.90.255.254113.90.255.25565,534
92113.91.0.0/16113.91.0.1 to 113.91.255.254113.91.255.25565,534
93113.92.0.0/16113.92.0.1 to 113.92.255.254113.92.255.25565,534
94113.93.0.0/16113.93.0.1 to 113.93.255.254113.93.255.25565,534
95113.94.0.0/16113.94.0.1 to 113.94.255.254113.94.255.25565,534
96113.95.0.0/16113.95.0.1 to 113.95.255.254113.95.255.25565,534
97113.96.0.0/16113.96.0.1 to 113.96.255.254113.96.255.25565,534
98113.97.0.0/16113.97.0.1 to 113.97.255.254113.97.255.25565,534
99113.98.0.0/16113.98.0.1 to 113.98.255.254113.98.255.25565,534
100113.99.0.0/16113.99.0.1 to 113.99.255.254113.99.255.25565,534
101113.100.0.0/16113.100.0.1 to 113.100.255.254113.100.255.25565,534
102113.101.0.0/16113.101.0.1 to 113.101.255.254113.101.255.25565,534
103113.102.0.0/16113.102.0.1 to 113.102.255.254113.102.255.25565,534
104113.103.0.0/16113.103.0.1 to 113.103.255.254113.103.255.25565,534
105113.104.0.0/16113.104.0.1 to 113.104.255.254113.104.255.25565,534
106113.105.0.0/16113.105.0.1 to 113.105.255.254113.105.255.25565,534
107113.106.0.0/16113.106.0.1 to 113.106.255.254113.106.255.25565,534
108113.107.0.0/16113.107.0.1 to 113.107.255.254113.107.255.25565,534
109113.108.0.0/16113.108.0.1 to 113.108.255.254113.108.255.25565,534
110113.109.0.0/16113.109.0.1 to 113.109.255.254113.109.255.25565,534
111113.110.0.0/16113.110.0.1 to 113.110.255.254113.110.255.25565,534
112113.111.0.0/16113.111.0.1 to 113.111.255.254113.111.255.25565,534
113113.112.0.0/16113.112.0.1 to 113.112.255.254113.112.255.25565,534
114113.113.0.0/16113.113.0.1 to 113.113.255.254113.113.255.25565,534
115113.114.0.0/16113.114.0.1 to 113.114.255.254113.114.255.25565,534
116113.115.0.0/16113.115.0.1 to 113.115.255.254113.115.255.25565,534
117113.116.0.0/16113.116.0.1 to 113.116.255.254113.116.255.25565,534
118113.117.0.0/16113.117.0.1 to 113.117.255.254113.117.255.25565,534
119113.118.0.0/16113.118.0.1 to 113.118.255.254113.118.255.25565,534
120113.119.0.0/16113.119.0.1 to 113.119.255.254113.119.255.25565,534
121113.120.0.0/16113.120.0.1 to 113.120.255.254113.120.255.25565,534
122113.121.0.0/16113.121.0.1 to 113.121.255.254113.121.255.25565,534
123113.122.0.0/16113.122.0.1 to 113.122.255.254113.122.255.25565,534
124113.123.0.0/16113.123.0.1 to 113.123.255.254113.123.255.25565,534
125113.124.0.0/16113.124.0.1 to 113.124.255.254113.124.255.25565,534
126113.125.0.0/16113.125.0.1 to 113.125.255.254113.125.255.25565,534
127113.126.0.0/16113.126.0.1 to 113.126.255.254113.126.255.25565,534
128113.127.0.0/16113.127.0.1 to 113.127.255.254113.127.255.25565,534
129113.128.0.0/16113.128.0.1 to 113.128.255.254113.128.255.25565,534
130113.129.0.0/16113.129.0.1 to 113.129.255.254113.129.255.25565,534
131113.130.0.0/16113.130.0.1 to 113.130.255.254113.130.255.25565,534
132113.131.0.0/16113.131.0.1 to 113.131.255.254113.131.255.25565,534
133113.132.0.0/16113.132.0.1 to 113.132.255.254113.132.255.25565,534
134113.133.0.0/16113.133.0.1 to 113.133.255.254113.133.255.25565,534
135113.134.0.0/16113.134.0.1 to 113.134.255.254113.134.255.25565,534
136113.135.0.0/16113.135.0.1 to 113.135.255.254113.135.255.25565,534
137113.136.0.0/16113.136.0.1 to 113.136.255.254113.136.255.25565,534
138113.137.0.0/16113.137.0.1 to 113.137.255.254113.137.255.25565,534
139113.138.0.0/16113.138.0.1 to 113.138.255.254113.138.255.25565,534
140113.139.0.0/16113.139.0.1 to 113.139.255.254113.139.255.25565,534
141113.140.0.0/16113.140.0.1 to 113.140.255.254113.140.255.25565,534
142113.141.0.0/16113.141.0.1 to 113.141.255.254113.141.255.25565,534
143113.142.0.0/16113.142.0.1 to 113.142.255.254113.142.255.25565,534
144113.143.0.0/16113.143.0.1 to 113.143.255.254113.143.255.25565,534
145113.144.0.0/16113.144.0.1 to 113.144.255.254113.144.255.25565,534
146113.145.0.0/16113.145.0.1 to 113.145.255.254113.145.255.25565,534
147113.146.0.0/16113.146.0.1 to 113.146.255.254113.146.255.25565,534
148113.147.0.0/16113.147.0.1 to 113.147.255.254113.147.255.25565,534
149113.148.0.0/16113.148.0.1 to 113.148.255.254113.148.255.25565,534
150113.149.0.0/16113.149.0.1 to 113.149.255.254113.149.255.25565,534
151113.150.0.0/16113.150.0.1 to 113.150.255.254113.150.255.25565,534
152113.151.0.0/16113.151.0.1 to 113.151.255.254113.151.255.25565,534
153113.152.0.0/16113.152.0.1 to 113.152.255.254113.152.255.25565,534
154113.153.0.0/16113.153.0.1 to 113.153.255.254113.153.255.25565,534
155113.154.0.0/16113.154.0.1 to 113.154.255.254113.154.255.25565,534
156113.155.0.0/16113.155.0.1 to 113.155.255.254113.155.255.25565,534
157113.156.0.0/16113.156.0.1 to 113.156.255.254113.156.255.25565,534
158113.157.0.0/16113.157.0.1 to 113.157.255.254113.157.255.25565,534
159113.158.0.0/16113.158.0.1 to 113.158.255.254113.158.255.25565,534
160113.159.0.0/16113.159.0.1 to 113.159.255.254113.159.255.25565,534
161113.160.0.0/16113.160.0.1 to 113.160.255.254113.160.255.25565,534
162113.161.0.0/16113.161.0.1 to 113.161.255.254113.161.255.25565,534
163113.162.0.0/16113.162.0.1 to 113.162.255.254113.162.255.25565,534
164113.163.0.0/16113.163.0.1 to 113.163.255.254113.163.255.25565,534
165113.164.0.0/16113.164.0.1 to 113.164.255.254113.164.255.25565,534
166113.165.0.0/16113.165.0.1 to 113.165.255.254113.165.255.25565,534
167113.166.0.0/16113.166.0.1 to 113.166.255.254113.166.255.25565,534
168113.167.0.0/16113.167.0.1 to 113.167.255.254113.167.255.25565,534
169113.168.0.0/16113.168.0.1 to 113.168.255.254113.168.255.25565,534
170113.169.0.0/16113.169.0.1 to 113.169.255.254113.169.255.25565,534
171113.170.0.0/16113.170.0.1 to 113.170.255.254113.170.255.25565,534
172113.171.0.0/16113.171.0.1 to 113.171.255.254113.171.255.25565,534
173113.172.0.0/16113.172.0.1 to 113.172.255.254113.172.255.25565,534
174113.173.0.0/16113.173.0.1 to 113.173.255.254113.173.255.25565,534
175113.174.0.0/16113.174.0.1 to 113.174.255.254113.174.255.25565,534
176113.175.0.0/16113.175.0.1 to 113.175.255.254113.175.255.25565,534
177113.176.0.0/16113.176.0.1 to 113.176.255.254113.176.255.25565,534
178113.177.0.0/16113.177.0.1 to 113.177.255.254113.177.255.25565,534
179113.178.0.0/16113.178.0.1 to 113.178.255.254113.178.255.25565,534
180113.179.0.0/16113.179.0.1 to 113.179.255.254113.179.255.25565,534
181113.180.0.0/16113.180.0.1 to 113.180.255.254113.180.255.25565,534
182113.181.0.0/16113.181.0.1 to 113.181.255.254113.181.255.25565,534
183113.182.0.0/16113.182.0.1 to 113.182.255.254113.182.255.25565,534
184113.183.0.0/16113.183.0.1 to 113.183.255.254113.183.255.25565,534
185113.184.0.0/16113.184.0.1 to 113.184.255.254113.184.255.25565,534
186113.185.0.0/16113.185.0.1 to 113.185.255.254113.185.255.25565,534
187113.186.0.0/16113.186.0.1 to 113.186.255.254113.186.255.25565,534
188113.187.0.0/16113.187.0.1 to 113.187.255.254113.187.255.25565,534
189113.188.0.0/16113.188.0.1 to 113.188.255.254113.188.255.25565,534
190113.189.0.0/16113.189.0.1 to 113.189.255.254113.189.255.25565,534
191113.190.0.0/16113.190.0.1 to 113.190.255.254113.190.255.25565,534
192113.191.0.0/16113.191.0.1 to 113.191.255.254113.191.255.25565,534
193113.192.0.0/16113.192.0.1 to 113.192.255.254113.192.255.25565,534
194113.193.0.0/16113.193.0.1 to 113.193.255.254113.193.255.25565,534
195113.194.0.0/16113.194.0.1 to 113.194.255.254113.194.255.25565,534
196113.195.0.0/16113.195.0.1 to 113.195.255.254113.195.255.25565,534
197113.196.0.0/16113.196.0.1 to 113.196.255.254113.196.255.25565,534
198113.197.0.0/16113.197.0.1 to 113.197.255.254113.197.255.25565,534
199113.198.0.0/16113.198.0.1 to 113.198.255.254113.198.255.25565,534
200113.199.0.0/16113.199.0.1 to 113.199.255.254113.199.255.25565,534
201113.200.0.0/16113.200.0.1 to 113.200.255.254113.200.255.25565,534
202113.201.0.0/16113.201.0.1 to 113.201.255.254113.201.255.25565,534
203113.202.0.0/16113.202.0.1 to 113.202.255.254113.202.255.25565,534
204113.203.0.0/16113.203.0.1 to 113.203.255.254113.203.255.25565,534
205113.204.0.0/16113.204.0.1 to 113.204.255.254113.204.255.25565,534
206113.205.0.0/16113.205.0.1 to 113.205.255.254113.205.255.25565,534
207113.206.0.0/16113.206.0.1 to 113.206.255.254113.206.255.25565,534
208113.207.0.0/16113.207.0.1 to 113.207.255.254113.207.255.25565,534
209113.208.0.0/16113.208.0.1 to 113.208.255.254113.208.255.25565,534
210113.209.0.0/16113.209.0.1 to 113.209.255.254113.209.255.25565,534
211113.210.0.0/16113.210.0.1 to 113.210.255.254113.210.255.25565,534
212113.211.0.0/16113.211.0.1 to 113.211.255.254113.211.255.25565,534
213113.212.0.0/16113.212.0.1 to 113.212.255.254113.212.255.25565,534
214113.213.0.0/16113.213.0.1 to 113.213.255.254113.213.255.25565,534
215113.214.0.0/16113.214.0.1 to 113.214.255.254113.214.255.25565,534
216113.215.0.0/16113.215.0.1 to 113.215.255.254113.215.255.25565,534
217113.216.0.0/16113.216.0.1 to 113.216.255.254113.216.255.25565,534
218113.217.0.0/16113.217.0.1 to 113.217.255.254113.217.255.25565,534
219113.218.0.0/16113.218.0.1 to 113.218.255.254113.218.255.25565,534
220113.219.0.0/16113.219.0.1 to 113.219.255.254113.219.255.25565,534
221113.220.0.0/16113.220.0.1 to 113.220.255.254113.220.255.25565,534
222113.221.0.0/16113.221.0.1 to 113.221.255.254113.221.255.25565,534
223113.222.0.0/16113.222.0.1 to 113.222.255.254113.222.255.25565,534
224113.223.0.0/16113.223.0.1 to 113.223.255.254113.223.255.25565,534
225113.224.0.0/16113.224.0.1 to 113.224.255.254113.224.255.25565,534
226113.225.0.0/16113.225.0.1 to 113.225.255.254113.225.255.25565,534
227113.226.0.0/16113.226.0.1 to 113.226.255.254113.226.255.25565,534
228113.227.0.0/16113.227.0.1 to 113.227.255.254113.227.255.25565,534
229113.228.0.0/16113.228.0.1 to 113.228.255.254113.228.255.25565,534
230113.229.0.0/16113.229.0.1 to 113.229.255.254113.229.255.25565,534
231113.230.0.0/16113.230.0.1 to 113.230.255.254113.230.255.25565,534
232113.231.0.0/16113.231.0.1 to 113.231.255.254113.231.255.25565,534
233113.232.0.0/16113.232.0.1 to 113.232.255.254113.232.255.25565,534
234113.233.0.0/16113.233.0.1 to 113.233.255.254113.233.255.25565,534
235113.234.0.0/16113.234.0.1 to 113.234.255.254113.234.255.25565,534
236113.235.0.0/16113.235.0.1 to 113.235.255.254113.235.255.25565,534
237113.236.0.0/16113.236.0.1 to 113.236.255.254113.236.255.25565,534
238113.237.0.0/16113.237.0.1 to 113.237.255.254113.237.255.25565,534
239113.238.0.0/16113.238.0.1 to 113.238.255.254113.238.255.25565,534
240113.239.0.0/16113.239.0.1 to 113.239.255.254113.239.255.25565,534
241113.240.0.0/16113.240.0.1 to 113.240.255.254113.240.255.25565,534
242113.241.0.0/16113.241.0.1 to 113.241.255.254113.241.255.25565,534
243113.242.0.0/16113.242.0.1 to 113.242.255.254113.242.255.25565,534
244113.243.0.0/16113.243.0.1 to 113.243.255.254113.243.255.25565,534
245113.244.0.0/16113.244.0.1 to 113.244.255.254113.244.255.25565,534
246113.245.0.0/16113.245.0.1 to 113.245.255.254113.245.255.25565,534
247113.246.0.0/16113.246.0.1 to 113.246.255.254113.246.255.25565,534
248113.247.0.0/16113.247.0.1 to 113.247.255.254113.247.255.25565,534
249113.248.0.0/16113.248.0.1 to 113.248.255.254113.248.255.25565,534
250113.249.0.0/16113.249.0.1 to 113.249.255.254113.249.255.25565,534
251113.250.0.0/16113.250.0.1 to 113.250.255.254113.250.255.25565,534
252113.251.0.0/16113.251.0.1 to 113.251.255.254113.251.255.25565,534
253113.252.0.0/16113.252.0.1 to 113.252.255.254113.252.255.25565,534
254113.253.0.0/16113.253.0.1 to 113.253.255.254113.253.255.25565,534
255113.254.0.0/16113.254.0.1 to 113.254.255.254113.254.255.25565,534
256113.255.0.0/16113.255.0.1 to 113.255.255.254113.255.255.25565,534

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.