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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.

Network113.76.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
113.76.0.0
Broadcast address
113.79.255.255
First usable
113.76.0.1
Last usable
113.79.255.254
Usable hosts
262,142 (262,144 less the network and broadcast addresses)
Subnet mask
255.252.0.0
Wildcard mask
0.3.255.255 (Cisco ACLs, OSPF)
Prefix length
/14
Type
Public public
Old class
A (default /8)
As numbers
Hex 714C0000 · Integer 1900806144 to 1901068287
Reverse DNS zones
76.113.in-addr.arpa
77.113.in-addr.arpa
78.113.in-addr.arpa
79.113.in-addr.arpa
/14 is not on a 8-bit boundary, so it takes 4 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01110001.01001100.00000000.00000000113.76.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network01110001.01001100.00000000.00000000113.76.0.0
Broadcast01110001.01001111.11111111.11111111113.79.255.255
Split into smaller subnets/23
/15 (2)/16 (4)/17 (8)/18 (16)/19 (32)/20 (64)/21 (128)/22 (256)/23 (512)/24 (1,024)/25 (2,048)/26 (4,096)

113.76.0.0/14 makes 512 subnets of /23; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1113.76.0.0/23113.76.0.1 to 113.76.1.254113.76.1.255510
2113.76.2.0/23113.76.2.1 to 113.76.3.254113.76.3.255510
3113.76.4.0/23113.76.4.1 to 113.76.5.254113.76.5.255510
4113.76.6.0/23113.76.6.1 to 113.76.7.254113.76.7.255510
5113.76.8.0/23113.76.8.1 to 113.76.9.254113.76.9.255510
6113.76.10.0/23113.76.10.1 to 113.76.11.254113.76.11.255510
7113.76.12.0/23113.76.12.1 to 113.76.13.254113.76.13.255510
8113.76.14.0/23113.76.14.1 to 113.76.15.254113.76.15.255510
9113.76.16.0/23113.76.16.1 to 113.76.17.254113.76.17.255510
10113.76.18.0/23113.76.18.1 to 113.76.19.254113.76.19.255510
11113.76.20.0/23113.76.20.1 to 113.76.21.254113.76.21.255510
12113.76.22.0/23113.76.22.1 to 113.76.23.254113.76.23.255510
13113.76.24.0/23113.76.24.1 to 113.76.25.254113.76.25.255510
14113.76.26.0/23113.76.26.1 to 113.76.27.254113.76.27.255510
15113.76.28.0/23113.76.28.1 to 113.76.29.254113.76.29.255510
16113.76.30.0/23113.76.30.1 to 113.76.31.254113.76.31.255510
17113.76.32.0/23113.76.32.1 to 113.76.33.254113.76.33.255510
18113.76.34.0/23113.76.34.1 to 113.76.35.254113.76.35.255510
19113.76.36.0/23113.76.36.1 to 113.76.37.254113.76.37.255510
20113.76.38.0/23113.76.38.1 to 113.76.39.254113.76.39.255510
21113.76.40.0/23113.76.40.1 to 113.76.41.254113.76.41.255510
22113.76.42.0/23113.76.42.1 to 113.76.43.254113.76.43.255510
23113.76.44.0/23113.76.44.1 to 113.76.45.254113.76.45.255510
24113.76.46.0/23113.76.46.1 to 113.76.47.254113.76.47.255510
25113.76.48.0/23113.76.48.1 to 113.76.49.254113.76.49.255510
26113.76.50.0/23113.76.50.1 to 113.76.51.254113.76.51.255510
27113.76.52.0/23113.76.52.1 to 113.76.53.254113.76.53.255510
28113.76.54.0/23113.76.54.1 to 113.76.55.254113.76.55.255510
29113.76.56.0/23113.76.56.1 to 113.76.57.254113.76.57.255510
30113.76.58.0/23113.76.58.1 to 113.76.59.254113.76.59.255510
31113.76.60.0/23113.76.60.1 to 113.76.61.254113.76.61.255510
32113.76.62.0/23113.76.62.1 to 113.76.63.254113.76.63.255510
33113.76.64.0/23113.76.64.1 to 113.76.65.254113.76.65.255510
34113.76.66.0/23113.76.66.1 to 113.76.67.254113.76.67.255510
35113.76.68.0/23113.76.68.1 to 113.76.69.254113.76.69.255510
36113.76.70.0/23113.76.70.1 to 113.76.71.254113.76.71.255510
37113.76.72.0/23113.76.72.1 to 113.76.73.254113.76.73.255510
38113.76.74.0/23113.76.74.1 to 113.76.75.254113.76.75.255510
39113.76.76.0/23113.76.76.1 to 113.76.77.254113.76.77.255510
40113.76.78.0/23113.76.78.1 to 113.76.79.254113.76.79.255510
41113.76.80.0/23113.76.80.1 to 113.76.81.254113.76.81.255510
42113.76.82.0/23113.76.82.1 to 113.76.83.254113.76.83.255510
43113.76.84.0/23113.76.84.1 to 113.76.85.254113.76.85.255510
44113.76.86.0/23113.76.86.1 to 113.76.87.254113.76.87.255510
45113.76.88.0/23113.76.88.1 to 113.76.89.254113.76.89.255510
46113.76.90.0/23113.76.90.1 to 113.76.91.254113.76.91.255510
47113.76.92.0/23113.76.92.1 to 113.76.93.254113.76.93.255510
48113.76.94.0/23113.76.94.1 to 113.76.95.254113.76.95.255510
49113.76.96.0/23113.76.96.1 to 113.76.97.254113.76.97.255510
50113.76.98.0/23113.76.98.1 to 113.76.99.254113.76.99.255510
51113.76.100.0/23113.76.100.1 to 113.76.101.254113.76.101.255510
52113.76.102.0/23113.76.102.1 to 113.76.103.254113.76.103.255510
53113.76.104.0/23113.76.104.1 to 113.76.105.254113.76.105.255510
54113.76.106.0/23113.76.106.1 to 113.76.107.254113.76.107.255510
55113.76.108.0/23113.76.108.1 to 113.76.109.254113.76.109.255510
56113.76.110.0/23113.76.110.1 to 113.76.111.254113.76.111.255510
57113.76.112.0/23113.76.112.1 to 113.76.113.254113.76.113.255510
58113.76.114.0/23113.76.114.1 to 113.76.115.254113.76.115.255510
59113.76.116.0/23113.76.116.1 to 113.76.117.254113.76.117.255510
60113.76.118.0/23113.76.118.1 to 113.76.119.254113.76.119.255510
61113.76.120.0/23113.76.120.1 to 113.76.121.254113.76.121.255510
62113.76.122.0/23113.76.122.1 to 113.76.123.254113.76.123.255510
63113.76.124.0/23113.76.124.1 to 113.76.125.254113.76.125.255510
64113.76.126.0/23113.76.126.1 to 113.76.127.254113.76.127.255510
65113.76.128.0/23113.76.128.1 to 113.76.129.254113.76.129.255510
66113.76.130.0/23113.76.130.1 to 113.76.131.254113.76.131.255510
67113.76.132.0/23113.76.132.1 to 113.76.133.254113.76.133.255510
68113.76.134.0/23113.76.134.1 to 113.76.135.254113.76.135.255510
69113.76.136.0/23113.76.136.1 to 113.76.137.254113.76.137.255510
70113.76.138.0/23113.76.138.1 to 113.76.139.254113.76.139.255510
71113.76.140.0/23113.76.140.1 to 113.76.141.254113.76.141.255510
72113.76.142.0/23113.76.142.1 to 113.76.143.254113.76.143.255510
73113.76.144.0/23113.76.144.1 to 113.76.145.254113.76.145.255510
74113.76.146.0/23113.76.146.1 to 113.76.147.254113.76.147.255510
75113.76.148.0/23113.76.148.1 to 113.76.149.254113.76.149.255510
76113.76.150.0/23113.76.150.1 to 113.76.151.254113.76.151.255510
77113.76.152.0/23113.76.152.1 to 113.76.153.254113.76.153.255510
78113.76.154.0/23113.76.154.1 to 113.76.155.254113.76.155.255510
79113.76.156.0/23113.76.156.1 to 113.76.157.254113.76.157.255510
80113.76.158.0/23113.76.158.1 to 113.76.159.254113.76.159.255510
81113.76.160.0/23113.76.160.1 to 113.76.161.254113.76.161.255510
82113.76.162.0/23113.76.162.1 to 113.76.163.254113.76.163.255510
83113.76.164.0/23113.76.164.1 to 113.76.165.254113.76.165.255510
84113.76.166.0/23113.76.166.1 to 113.76.167.254113.76.167.255510
85113.76.168.0/23113.76.168.1 to 113.76.169.254113.76.169.255510
86113.76.170.0/23113.76.170.1 to 113.76.171.254113.76.171.255510
87113.76.172.0/23113.76.172.1 to 113.76.173.254113.76.173.255510
88113.76.174.0/23113.76.174.1 to 113.76.175.254113.76.175.255510
89113.76.176.0/23113.76.176.1 to 113.76.177.254113.76.177.255510
90113.76.178.0/23113.76.178.1 to 113.76.179.254113.76.179.255510
91113.76.180.0/23113.76.180.1 to 113.76.181.254113.76.181.255510
92113.76.182.0/23113.76.182.1 to 113.76.183.254113.76.183.255510
93113.76.184.0/23113.76.184.1 to 113.76.185.254113.76.185.255510
94113.76.186.0/23113.76.186.1 to 113.76.187.254113.76.187.255510
95113.76.188.0/23113.76.188.1 to 113.76.189.254113.76.189.255510
96113.76.190.0/23113.76.190.1 to 113.76.191.254113.76.191.255510
97113.76.192.0/23113.76.192.1 to 113.76.193.254113.76.193.255510
98113.76.194.0/23113.76.194.1 to 113.76.195.254113.76.195.255510
99113.76.196.0/23113.76.196.1 to 113.76.197.254113.76.197.255510
100113.76.198.0/23113.76.198.1 to 113.76.199.254113.76.199.255510
101113.76.200.0/23113.76.200.1 to 113.76.201.254113.76.201.255510
102113.76.202.0/23113.76.202.1 to 113.76.203.254113.76.203.255510
103113.76.204.0/23113.76.204.1 to 113.76.205.254113.76.205.255510
104113.76.206.0/23113.76.206.1 to 113.76.207.254113.76.207.255510
105113.76.208.0/23113.76.208.1 to 113.76.209.254113.76.209.255510
106113.76.210.0/23113.76.210.1 to 113.76.211.254113.76.211.255510
107113.76.212.0/23113.76.212.1 to 113.76.213.254113.76.213.255510
108113.76.214.0/23113.76.214.1 to 113.76.215.254113.76.215.255510
109113.76.216.0/23113.76.216.1 to 113.76.217.254113.76.217.255510
110113.76.218.0/23113.76.218.1 to 113.76.219.254113.76.219.255510
111113.76.220.0/23113.76.220.1 to 113.76.221.254113.76.221.255510
112113.76.222.0/23113.76.222.1 to 113.76.223.254113.76.223.255510
113113.76.224.0/23113.76.224.1 to 113.76.225.254113.76.225.255510
114113.76.226.0/23113.76.226.1 to 113.76.227.254113.76.227.255510
115113.76.228.0/23113.76.228.1 to 113.76.229.254113.76.229.255510
116113.76.230.0/23113.76.230.1 to 113.76.231.254113.76.231.255510
117113.76.232.0/23113.76.232.1 to 113.76.233.254113.76.233.255510
118113.76.234.0/23113.76.234.1 to 113.76.235.254113.76.235.255510
119113.76.236.0/23113.76.236.1 to 113.76.237.254113.76.237.255510
120113.76.238.0/23113.76.238.1 to 113.76.239.254113.76.239.255510
121113.76.240.0/23113.76.240.1 to 113.76.241.254113.76.241.255510
122113.76.242.0/23113.76.242.1 to 113.76.243.254113.76.243.255510
123113.76.244.0/23113.76.244.1 to 113.76.245.254113.76.245.255510
124113.76.246.0/23113.76.246.1 to 113.76.247.254113.76.247.255510
125113.76.248.0/23113.76.248.1 to 113.76.249.254113.76.249.255510
126113.76.250.0/23113.76.250.1 to 113.76.251.254113.76.251.255510
127113.76.252.0/23113.76.252.1 to 113.76.253.254113.76.253.255510
128113.76.254.0/23113.76.254.1 to 113.76.255.254113.76.255.255510
129113.77.0.0/23113.77.0.1 to 113.77.1.254113.77.1.255510
130113.77.2.0/23113.77.2.1 to 113.77.3.254113.77.3.255510
131113.77.4.0/23113.77.4.1 to 113.77.5.254113.77.5.255510
132113.77.6.0/23113.77.6.1 to 113.77.7.254113.77.7.255510
133113.77.8.0/23113.77.8.1 to 113.77.9.254113.77.9.255510
134113.77.10.0/23113.77.10.1 to 113.77.11.254113.77.11.255510
135113.77.12.0/23113.77.12.1 to 113.77.13.254113.77.13.255510
136113.77.14.0/23113.77.14.1 to 113.77.15.254113.77.15.255510
137113.77.16.0/23113.77.16.1 to 113.77.17.254113.77.17.255510
138113.77.18.0/23113.77.18.1 to 113.77.19.254113.77.19.255510
139113.77.20.0/23113.77.20.1 to 113.77.21.254113.77.21.255510
140113.77.22.0/23113.77.22.1 to 113.77.23.254113.77.23.255510
141113.77.24.0/23113.77.24.1 to 113.77.25.254113.77.25.255510
142113.77.26.0/23113.77.26.1 to 113.77.27.254113.77.27.255510
143113.77.28.0/23113.77.28.1 to 113.77.29.254113.77.29.255510
144113.77.30.0/23113.77.30.1 to 113.77.31.254113.77.31.255510
145113.77.32.0/23113.77.32.1 to 113.77.33.254113.77.33.255510
146113.77.34.0/23113.77.34.1 to 113.77.35.254113.77.35.255510
147113.77.36.0/23113.77.36.1 to 113.77.37.254113.77.37.255510
148113.77.38.0/23113.77.38.1 to 113.77.39.254113.77.39.255510
149113.77.40.0/23113.77.40.1 to 113.77.41.254113.77.41.255510
150113.77.42.0/23113.77.42.1 to 113.77.43.254113.77.43.255510
151113.77.44.0/23113.77.44.1 to 113.77.45.254113.77.45.255510
152113.77.46.0/23113.77.46.1 to 113.77.47.254113.77.47.255510
153113.77.48.0/23113.77.48.1 to 113.77.49.254113.77.49.255510
154113.77.50.0/23113.77.50.1 to 113.77.51.254113.77.51.255510
155113.77.52.0/23113.77.52.1 to 113.77.53.254113.77.53.255510
156113.77.54.0/23113.77.54.1 to 113.77.55.254113.77.55.255510
157113.77.56.0/23113.77.56.1 to 113.77.57.254113.77.57.255510
158113.77.58.0/23113.77.58.1 to 113.77.59.254113.77.59.255510
159113.77.60.0/23113.77.60.1 to 113.77.61.254113.77.61.255510
160113.77.62.0/23113.77.62.1 to 113.77.63.254113.77.63.255510
161113.77.64.0/23113.77.64.1 to 113.77.65.254113.77.65.255510
162113.77.66.0/23113.77.66.1 to 113.77.67.254113.77.67.255510
163113.77.68.0/23113.77.68.1 to 113.77.69.254113.77.69.255510
164113.77.70.0/23113.77.70.1 to 113.77.71.254113.77.71.255510
165113.77.72.0/23113.77.72.1 to 113.77.73.254113.77.73.255510
166113.77.74.0/23113.77.74.1 to 113.77.75.254113.77.75.255510
167113.77.76.0/23113.77.76.1 to 113.77.77.254113.77.77.255510
168113.77.78.0/23113.77.78.1 to 113.77.79.254113.77.79.255510
169113.77.80.0/23113.77.80.1 to 113.77.81.254113.77.81.255510
170113.77.82.0/23113.77.82.1 to 113.77.83.254113.77.83.255510
171113.77.84.0/23113.77.84.1 to 113.77.85.254113.77.85.255510
172113.77.86.0/23113.77.86.1 to 113.77.87.254113.77.87.255510
173113.77.88.0/23113.77.88.1 to 113.77.89.254113.77.89.255510
174113.77.90.0/23113.77.90.1 to 113.77.91.254113.77.91.255510
175113.77.92.0/23113.77.92.1 to 113.77.93.254113.77.93.255510
176113.77.94.0/23113.77.94.1 to 113.77.95.254113.77.95.255510
177113.77.96.0/23113.77.96.1 to 113.77.97.254113.77.97.255510
178113.77.98.0/23113.77.98.1 to 113.77.99.254113.77.99.255510
179113.77.100.0/23113.77.100.1 to 113.77.101.254113.77.101.255510
180113.77.102.0/23113.77.102.1 to 113.77.103.254113.77.103.255510
181113.77.104.0/23113.77.104.1 to 113.77.105.254113.77.105.255510
182113.77.106.0/23113.77.106.1 to 113.77.107.254113.77.107.255510
183113.77.108.0/23113.77.108.1 to 113.77.109.254113.77.109.255510
184113.77.110.0/23113.77.110.1 to 113.77.111.254113.77.111.255510
185113.77.112.0/23113.77.112.1 to 113.77.113.254113.77.113.255510
186113.77.114.0/23113.77.114.1 to 113.77.115.254113.77.115.255510
187113.77.116.0/23113.77.116.1 to 113.77.117.254113.77.117.255510
188113.77.118.0/23113.77.118.1 to 113.77.119.254113.77.119.255510
189113.77.120.0/23113.77.120.1 to 113.77.121.254113.77.121.255510
190113.77.122.0/23113.77.122.1 to 113.77.123.254113.77.123.255510
191113.77.124.0/23113.77.124.1 to 113.77.125.254113.77.125.255510
192113.77.126.0/23113.77.126.1 to 113.77.127.254113.77.127.255510
193113.77.128.0/23113.77.128.1 to 113.77.129.254113.77.129.255510
194113.77.130.0/23113.77.130.1 to 113.77.131.254113.77.131.255510
195113.77.132.0/23113.77.132.1 to 113.77.133.254113.77.133.255510
196113.77.134.0/23113.77.134.1 to 113.77.135.254113.77.135.255510
197113.77.136.0/23113.77.136.1 to 113.77.137.254113.77.137.255510
198113.77.138.0/23113.77.138.1 to 113.77.139.254113.77.139.255510
199113.77.140.0/23113.77.140.1 to 113.77.141.254113.77.141.255510
200113.77.142.0/23113.77.142.1 to 113.77.143.254113.77.143.255510
201113.77.144.0/23113.77.144.1 to 113.77.145.254113.77.145.255510
202113.77.146.0/23113.77.146.1 to 113.77.147.254113.77.147.255510
203113.77.148.0/23113.77.148.1 to 113.77.149.254113.77.149.255510
204113.77.150.0/23113.77.150.1 to 113.77.151.254113.77.151.255510
205113.77.152.0/23113.77.152.1 to 113.77.153.254113.77.153.255510
206113.77.154.0/23113.77.154.1 to 113.77.155.254113.77.155.255510
207113.77.156.0/23113.77.156.1 to 113.77.157.254113.77.157.255510
208113.77.158.0/23113.77.158.1 to 113.77.159.254113.77.159.255510
209113.77.160.0/23113.77.160.1 to 113.77.161.254113.77.161.255510
210113.77.162.0/23113.77.162.1 to 113.77.163.254113.77.163.255510
211113.77.164.0/23113.77.164.1 to 113.77.165.254113.77.165.255510
212113.77.166.0/23113.77.166.1 to 113.77.167.254113.77.167.255510
213113.77.168.0/23113.77.168.1 to 113.77.169.254113.77.169.255510
214113.77.170.0/23113.77.170.1 to 113.77.171.254113.77.171.255510
215113.77.172.0/23113.77.172.1 to 113.77.173.254113.77.173.255510
216113.77.174.0/23113.77.174.1 to 113.77.175.254113.77.175.255510
217113.77.176.0/23113.77.176.1 to 113.77.177.254113.77.177.255510
218113.77.178.0/23113.77.178.1 to 113.77.179.254113.77.179.255510
219113.77.180.0/23113.77.180.1 to 113.77.181.254113.77.181.255510
220113.77.182.0/23113.77.182.1 to 113.77.183.254113.77.183.255510
221113.77.184.0/23113.77.184.1 to 113.77.185.254113.77.185.255510
222113.77.186.0/23113.77.186.1 to 113.77.187.254113.77.187.255510
223113.77.188.0/23113.77.188.1 to 113.77.189.254113.77.189.255510
224113.77.190.0/23113.77.190.1 to 113.77.191.254113.77.191.255510
225113.77.192.0/23113.77.192.1 to 113.77.193.254113.77.193.255510
226113.77.194.0/23113.77.194.1 to 113.77.195.254113.77.195.255510
227113.77.196.0/23113.77.196.1 to 113.77.197.254113.77.197.255510
228113.77.198.0/23113.77.198.1 to 113.77.199.254113.77.199.255510
229113.77.200.0/23113.77.200.1 to 113.77.201.254113.77.201.255510
230113.77.202.0/23113.77.202.1 to 113.77.203.254113.77.203.255510
231113.77.204.0/23113.77.204.1 to 113.77.205.254113.77.205.255510
232113.77.206.0/23113.77.206.1 to 113.77.207.254113.77.207.255510
233113.77.208.0/23113.77.208.1 to 113.77.209.254113.77.209.255510
234113.77.210.0/23113.77.210.1 to 113.77.211.254113.77.211.255510
235113.77.212.0/23113.77.212.1 to 113.77.213.254113.77.213.255510
236113.77.214.0/23113.77.214.1 to 113.77.215.254113.77.215.255510
237113.77.216.0/23113.77.216.1 to 113.77.217.254113.77.217.255510
238113.77.218.0/23113.77.218.1 to 113.77.219.254113.77.219.255510
239113.77.220.0/23113.77.220.1 to 113.77.221.254113.77.221.255510
240113.77.222.0/23113.77.222.1 to 113.77.223.254113.77.223.255510
241113.77.224.0/23113.77.224.1 to 113.77.225.254113.77.225.255510
242113.77.226.0/23113.77.226.1 to 113.77.227.254113.77.227.255510
243113.77.228.0/23113.77.228.1 to 113.77.229.254113.77.229.255510
244113.77.230.0/23113.77.230.1 to 113.77.231.254113.77.231.255510
245113.77.232.0/23113.77.232.1 to 113.77.233.254113.77.233.255510
246113.77.234.0/23113.77.234.1 to 113.77.235.254113.77.235.255510
247113.77.236.0/23113.77.236.1 to 113.77.237.254113.77.237.255510
248113.77.238.0/23113.77.238.1 to 113.77.239.254113.77.239.255510
249113.77.240.0/23113.77.240.1 to 113.77.241.254113.77.241.255510
250113.77.242.0/23113.77.242.1 to 113.77.243.254113.77.243.255510
251113.77.244.0/23113.77.244.1 to 113.77.245.254113.77.245.255510
252113.77.246.0/23113.77.246.1 to 113.77.247.254113.77.247.255510
253113.77.248.0/23113.77.248.1 to 113.77.249.254113.77.249.255510
254113.77.250.0/23113.77.250.1 to 113.77.251.254113.77.251.255510
255113.77.252.0/23113.77.252.1 to 113.77.253.254113.77.253.255510
256113.77.254.0/23113.77.254.1 to 113.77.255.254113.77.255.255510

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.