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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.

Network107.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
107.0.0.0
Broadcast address
107.255.255.255
First usable
107.0.0.1
Last usable
107.255.255.254
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 6B000000 · Integer 1795162112 to 1811939327
Reverse DNS zone
107.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01101011..00000000.00000000.00000000107.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network01101011..00000000.00000000.00000000107.0.0.0
Broadcast01101011..11111111.11111111.11111111107.255.255.255
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)

107.0.0.0/8 makes 256 subnets of /16.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1107.0.0.0/16107.0.0.1 to 107.0.255.254107.0.255.25565,534
2107.1.0.0/16107.1.0.1 to 107.1.255.254107.1.255.25565,534
3107.2.0.0/16107.2.0.1 to 107.2.255.254107.2.255.25565,534
4107.3.0.0/16107.3.0.1 to 107.3.255.254107.3.255.25565,534
5107.4.0.0/16107.4.0.1 to 107.4.255.254107.4.255.25565,534
6107.5.0.0/16107.5.0.1 to 107.5.255.254107.5.255.25565,534
7107.6.0.0/16107.6.0.1 to 107.6.255.254107.6.255.25565,534
8107.7.0.0/16107.7.0.1 to 107.7.255.254107.7.255.25565,534
9107.8.0.0/16107.8.0.1 to 107.8.255.254107.8.255.25565,534
10107.9.0.0/16107.9.0.1 to 107.9.255.254107.9.255.25565,534
11107.10.0.0/16107.10.0.1 to 107.10.255.254107.10.255.25565,534
12107.11.0.0/16107.11.0.1 to 107.11.255.254107.11.255.25565,534
13107.12.0.0/16107.12.0.1 to 107.12.255.254107.12.255.25565,534
14107.13.0.0/16107.13.0.1 to 107.13.255.254107.13.255.25565,534
15107.14.0.0/16107.14.0.1 to 107.14.255.254107.14.255.25565,534
16107.15.0.0/16107.15.0.1 to 107.15.255.254107.15.255.25565,534
17107.16.0.0/16107.16.0.1 to 107.16.255.254107.16.255.25565,534
18107.17.0.0/16107.17.0.1 to 107.17.255.254107.17.255.25565,534
19107.18.0.0/16107.18.0.1 to 107.18.255.254107.18.255.25565,534
20107.19.0.0/16107.19.0.1 to 107.19.255.254107.19.255.25565,534
21107.20.0.0/16107.20.0.1 to 107.20.255.254107.20.255.25565,534
22107.21.0.0/16107.21.0.1 to 107.21.255.254107.21.255.25565,534
23107.22.0.0/16107.22.0.1 to 107.22.255.254107.22.255.25565,534
24107.23.0.0/16107.23.0.1 to 107.23.255.254107.23.255.25565,534
25107.24.0.0/16107.24.0.1 to 107.24.255.254107.24.255.25565,534
26107.25.0.0/16107.25.0.1 to 107.25.255.254107.25.255.25565,534
27107.26.0.0/16107.26.0.1 to 107.26.255.254107.26.255.25565,534
28107.27.0.0/16107.27.0.1 to 107.27.255.254107.27.255.25565,534
29107.28.0.0/16107.28.0.1 to 107.28.255.254107.28.255.25565,534
30107.29.0.0/16107.29.0.1 to 107.29.255.254107.29.255.25565,534
31107.30.0.0/16107.30.0.1 to 107.30.255.254107.30.255.25565,534
32107.31.0.0/16107.31.0.1 to 107.31.255.254107.31.255.25565,534
33107.32.0.0/16107.32.0.1 to 107.32.255.254107.32.255.25565,534
34107.33.0.0/16107.33.0.1 to 107.33.255.254107.33.255.25565,534
35107.34.0.0/16107.34.0.1 to 107.34.255.254107.34.255.25565,534
36107.35.0.0/16107.35.0.1 to 107.35.255.254107.35.255.25565,534
37107.36.0.0/16107.36.0.1 to 107.36.255.254107.36.255.25565,534
38107.37.0.0/16107.37.0.1 to 107.37.255.254107.37.255.25565,534
39107.38.0.0/16107.38.0.1 to 107.38.255.254107.38.255.25565,534
40107.39.0.0/16107.39.0.1 to 107.39.255.254107.39.255.25565,534
41107.40.0.0/16107.40.0.1 to 107.40.255.254107.40.255.25565,534
42107.41.0.0/16107.41.0.1 to 107.41.255.254107.41.255.25565,534
43107.42.0.0/16107.42.0.1 to 107.42.255.254107.42.255.25565,534
44107.43.0.0/16107.43.0.1 to 107.43.255.254107.43.255.25565,534
45107.44.0.0/16107.44.0.1 to 107.44.255.254107.44.255.25565,534
46107.45.0.0/16107.45.0.1 to 107.45.255.254107.45.255.25565,534
47107.46.0.0/16107.46.0.1 to 107.46.255.254107.46.255.25565,534
48107.47.0.0/16107.47.0.1 to 107.47.255.254107.47.255.25565,534
49107.48.0.0/16107.48.0.1 to 107.48.255.254107.48.255.25565,534
50107.49.0.0/16107.49.0.1 to 107.49.255.254107.49.255.25565,534
51107.50.0.0/16107.50.0.1 to 107.50.255.254107.50.255.25565,534
52107.51.0.0/16107.51.0.1 to 107.51.255.254107.51.255.25565,534
53107.52.0.0/16107.52.0.1 to 107.52.255.254107.52.255.25565,534
54107.53.0.0/16107.53.0.1 to 107.53.255.254107.53.255.25565,534
55107.54.0.0/16107.54.0.1 to 107.54.255.254107.54.255.25565,534
56107.55.0.0/16107.55.0.1 to 107.55.255.254107.55.255.25565,534
57107.56.0.0/16107.56.0.1 to 107.56.255.254107.56.255.25565,534
58107.57.0.0/16107.57.0.1 to 107.57.255.254107.57.255.25565,534
59107.58.0.0/16107.58.0.1 to 107.58.255.254107.58.255.25565,534
60107.59.0.0/16107.59.0.1 to 107.59.255.254107.59.255.25565,534
61107.60.0.0/16107.60.0.1 to 107.60.255.254107.60.255.25565,534
62107.61.0.0/16107.61.0.1 to 107.61.255.254107.61.255.25565,534
63107.62.0.0/16107.62.0.1 to 107.62.255.254107.62.255.25565,534
64107.63.0.0/16107.63.0.1 to 107.63.255.254107.63.255.25565,534
65107.64.0.0/16107.64.0.1 to 107.64.255.254107.64.255.25565,534
66107.65.0.0/16107.65.0.1 to 107.65.255.254107.65.255.25565,534
67107.66.0.0/16107.66.0.1 to 107.66.255.254107.66.255.25565,534
68107.67.0.0/16107.67.0.1 to 107.67.255.254107.67.255.25565,534
69107.68.0.0/16107.68.0.1 to 107.68.255.254107.68.255.25565,534
70107.69.0.0/16107.69.0.1 to 107.69.255.254107.69.255.25565,534
71107.70.0.0/16107.70.0.1 to 107.70.255.254107.70.255.25565,534
72107.71.0.0/16107.71.0.1 to 107.71.255.254107.71.255.25565,534
73107.72.0.0/16107.72.0.1 to 107.72.255.254107.72.255.25565,534
74107.73.0.0/16107.73.0.1 to 107.73.255.254107.73.255.25565,534
75107.74.0.0/16107.74.0.1 to 107.74.255.254107.74.255.25565,534
76107.75.0.0/16107.75.0.1 to 107.75.255.254107.75.255.25565,534
77107.76.0.0/16107.76.0.1 to 107.76.255.254107.76.255.25565,534
78107.77.0.0/16107.77.0.1 to 107.77.255.254107.77.255.25565,534
79107.78.0.0/16107.78.0.1 to 107.78.255.254107.78.255.25565,534
80107.79.0.0/16107.79.0.1 to 107.79.255.254107.79.255.25565,534
81107.80.0.0/16107.80.0.1 to 107.80.255.254107.80.255.25565,534
82107.81.0.0/16107.81.0.1 to 107.81.255.254107.81.255.25565,534
83107.82.0.0/16107.82.0.1 to 107.82.255.254107.82.255.25565,534
84107.83.0.0/16107.83.0.1 to 107.83.255.254107.83.255.25565,534
85107.84.0.0/16107.84.0.1 to 107.84.255.254107.84.255.25565,534
86107.85.0.0/16107.85.0.1 to 107.85.255.254107.85.255.25565,534
87107.86.0.0/16107.86.0.1 to 107.86.255.254107.86.255.25565,534
88107.87.0.0/16107.87.0.1 to 107.87.255.254107.87.255.25565,534
89107.88.0.0/16107.88.0.1 to 107.88.255.254107.88.255.25565,534
90107.89.0.0/16107.89.0.1 to 107.89.255.254107.89.255.25565,534
91107.90.0.0/16107.90.0.1 to 107.90.255.254107.90.255.25565,534
92107.91.0.0/16107.91.0.1 to 107.91.255.254107.91.255.25565,534
93107.92.0.0/16107.92.0.1 to 107.92.255.254107.92.255.25565,534
94107.93.0.0/16107.93.0.1 to 107.93.255.254107.93.255.25565,534
95107.94.0.0/16107.94.0.1 to 107.94.255.254107.94.255.25565,534
96107.95.0.0/16107.95.0.1 to 107.95.255.254107.95.255.25565,534
97107.96.0.0/16107.96.0.1 to 107.96.255.254107.96.255.25565,534
98107.97.0.0/16107.97.0.1 to 107.97.255.254107.97.255.25565,534
99107.98.0.0/16107.98.0.1 to 107.98.255.254107.98.255.25565,534
100107.99.0.0/16107.99.0.1 to 107.99.255.254107.99.255.25565,534
101107.100.0.0/16107.100.0.1 to 107.100.255.254107.100.255.25565,534
102107.101.0.0/16107.101.0.1 to 107.101.255.254107.101.255.25565,534
103107.102.0.0/16107.102.0.1 to 107.102.255.254107.102.255.25565,534
104107.103.0.0/16107.103.0.1 to 107.103.255.254107.103.255.25565,534
105107.104.0.0/16107.104.0.1 to 107.104.255.254107.104.255.25565,534
106107.105.0.0/16107.105.0.1 to 107.105.255.254107.105.255.25565,534
107107.106.0.0/16107.106.0.1 to 107.106.255.254107.106.255.25565,534
108107.107.0.0/16107.107.0.1 to 107.107.255.254107.107.255.25565,534
109107.108.0.0/16107.108.0.1 to 107.108.255.254107.108.255.25565,534
110107.109.0.0/16107.109.0.1 to 107.109.255.254107.109.255.25565,534
111107.110.0.0/16107.110.0.1 to 107.110.255.254107.110.255.25565,534
112107.111.0.0/16107.111.0.1 to 107.111.255.254107.111.255.25565,534
113107.112.0.0/16107.112.0.1 to 107.112.255.254107.112.255.25565,534
114107.113.0.0/16107.113.0.1 to 107.113.255.254107.113.255.25565,534
115107.114.0.0/16107.114.0.1 to 107.114.255.254107.114.255.25565,534
116107.115.0.0/16107.115.0.1 to 107.115.255.254107.115.255.25565,534
117107.116.0.0/16107.116.0.1 to 107.116.255.254107.116.255.25565,534
118107.117.0.0/16107.117.0.1 to 107.117.255.254107.117.255.25565,534
119107.118.0.0/16107.118.0.1 to 107.118.255.254107.118.255.25565,534
120107.119.0.0/16107.119.0.1 to 107.119.255.254107.119.255.25565,534
121107.120.0.0/16107.120.0.1 to 107.120.255.254107.120.255.25565,534
122107.121.0.0/16107.121.0.1 to 107.121.255.254107.121.255.25565,534
123107.122.0.0/16107.122.0.1 to 107.122.255.254107.122.255.25565,534
124107.123.0.0/16107.123.0.1 to 107.123.255.254107.123.255.25565,534
125107.124.0.0/16107.124.0.1 to 107.124.255.254107.124.255.25565,534
126107.125.0.0/16107.125.0.1 to 107.125.255.254107.125.255.25565,534
127107.126.0.0/16107.126.0.1 to 107.126.255.254107.126.255.25565,534
128107.127.0.0/16107.127.0.1 to 107.127.255.254107.127.255.25565,534
129107.128.0.0/16107.128.0.1 to 107.128.255.254107.128.255.25565,534
130107.129.0.0/16107.129.0.1 to 107.129.255.254107.129.255.25565,534
131107.130.0.0/16107.130.0.1 to 107.130.255.254107.130.255.25565,534
132107.131.0.0/16107.131.0.1 to 107.131.255.254107.131.255.25565,534
133107.132.0.0/16107.132.0.1 to 107.132.255.254107.132.255.25565,534
134107.133.0.0/16107.133.0.1 to 107.133.255.254107.133.255.25565,534
135107.134.0.0/16107.134.0.1 to 107.134.255.254107.134.255.25565,534
136107.135.0.0/16107.135.0.1 to 107.135.255.254107.135.255.25565,534
137107.136.0.0/16107.136.0.1 to 107.136.255.254107.136.255.25565,534
138107.137.0.0/16107.137.0.1 to 107.137.255.254107.137.255.25565,534
139107.138.0.0/16107.138.0.1 to 107.138.255.254107.138.255.25565,534
140107.139.0.0/16107.139.0.1 to 107.139.255.254107.139.255.25565,534
141107.140.0.0/16107.140.0.1 to 107.140.255.254107.140.255.25565,534
142107.141.0.0/16107.141.0.1 to 107.141.255.254107.141.255.25565,534
143107.142.0.0/16107.142.0.1 to 107.142.255.254107.142.255.25565,534
144107.143.0.0/16107.143.0.1 to 107.143.255.254107.143.255.25565,534
145107.144.0.0/16107.144.0.1 to 107.144.255.254107.144.255.25565,534
146107.145.0.0/16107.145.0.1 to 107.145.255.254107.145.255.25565,534
147107.146.0.0/16107.146.0.1 to 107.146.255.254107.146.255.25565,534
148107.147.0.0/16107.147.0.1 to 107.147.255.254107.147.255.25565,534
149107.148.0.0/16107.148.0.1 to 107.148.255.254107.148.255.25565,534
150107.149.0.0/16107.149.0.1 to 107.149.255.254107.149.255.25565,534
151107.150.0.0/16107.150.0.1 to 107.150.255.254107.150.255.25565,534
152107.151.0.0/16107.151.0.1 to 107.151.255.254107.151.255.25565,534
153107.152.0.0/16107.152.0.1 to 107.152.255.254107.152.255.25565,534
154107.153.0.0/16107.153.0.1 to 107.153.255.254107.153.255.25565,534
155107.154.0.0/16107.154.0.1 to 107.154.255.254107.154.255.25565,534
156107.155.0.0/16107.155.0.1 to 107.155.255.254107.155.255.25565,534
157107.156.0.0/16107.156.0.1 to 107.156.255.254107.156.255.25565,534
158107.157.0.0/16107.157.0.1 to 107.157.255.254107.157.255.25565,534
159107.158.0.0/16107.158.0.1 to 107.158.255.254107.158.255.25565,534
160107.159.0.0/16107.159.0.1 to 107.159.255.254107.159.255.25565,534
161107.160.0.0/16107.160.0.1 to 107.160.255.254107.160.255.25565,534
162107.161.0.0/16107.161.0.1 to 107.161.255.254107.161.255.25565,534
163107.162.0.0/16107.162.0.1 to 107.162.255.254107.162.255.25565,534
164107.163.0.0/16107.163.0.1 to 107.163.255.254107.163.255.25565,534
165107.164.0.0/16107.164.0.1 to 107.164.255.254107.164.255.25565,534
166107.165.0.0/16107.165.0.1 to 107.165.255.254107.165.255.25565,534
167107.166.0.0/16107.166.0.1 to 107.166.255.254107.166.255.25565,534
168107.167.0.0/16107.167.0.1 to 107.167.255.254107.167.255.25565,534
169107.168.0.0/16107.168.0.1 to 107.168.255.254107.168.255.25565,534
170107.169.0.0/16107.169.0.1 to 107.169.255.254107.169.255.25565,534
171107.170.0.0/16107.170.0.1 to 107.170.255.254107.170.255.25565,534
172107.171.0.0/16107.171.0.1 to 107.171.255.254107.171.255.25565,534
173107.172.0.0/16107.172.0.1 to 107.172.255.254107.172.255.25565,534
174107.173.0.0/16107.173.0.1 to 107.173.255.254107.173.255.25565,534
175107.174.0.0/16107.174.0.1 to 107.174.255.254107.174.255.25565,534
176107.175.0.0/16107.175.0.1 to 107.175.255.254107.175.255.25565,534
177107.176.0.0/16107.176.0.1 to 107.176.255.254107.176.255.25565,534
178107.177.0.0/16107.177.0.1 to 107.177.255.254107.177.255.25565,534
179107.178.0.0/16107.178.0.1 to 107.178.255.254107.178.255.25565,534
180107.179.0.0/16107.179.0.1 to 107.179.255.254107.179.255.25565,534
181107.180.0.0/16107.180.0.1 to 107.180.255.254107.180.255.25565,534
182107.181.0.0/16107.181.0.1 to 107.181.255.254107.181.255.25565,534
183107.182.0.0/16107.182.0.1 to 107.182.255.254107.182.255.25565,534
184107.183.0.0/16107.183.0.1 to 107.183.255.254107.183.255.25565,534
185107.184.0.0/16107.184.0.1 to 107.184.255.254107.184.255.25565,534
186107.185.0.0/16107.185.0.1 to 107.185.255.254107.185.255.25565,534
187107.186.0.0/16107.186.0.1 to 107.186.255.254107.186.255.25565,534
188107.187.0.0/16107.187.0.1 to 107.187.255.254107.187.255.25565,534
189107.188.0.0/16107.188.0.1 to 107.188.255.254107.188.255.25565,534
190107.189.0.0/16107.189.0.1 to 107.189.255.254107.189.255.25565,534
191107.190.0.0/16107.190.0.1 to 107.190.255.254107.190.255.25565,534
192107.191.0.0/16107.191.0.1 to 107.191.255.254107.191.255.25565,534
193107.192.0.0/16107.192.0.1 to 107.192.255.254107.192.255.25565,534
194107.193.0.0/16107.193.0.1 to 107.193.255.254107.193.255.25565,534
195107.194.0.0/16107.194.0.1 to 107.194.255.254107.194.255.25565,534
196107.195.0.0/16107.195.0.1 to 107.195.255.254107.195.255.25565,534
197107.196.0.0/16107.196.0.1 to 107.196.255.254107.196.255.25565,534
198107.197.0.0/16107.197.0.1 to 107.197.255.254107.197.255.25565,534
199107.198.0.0/16107.198.0.1 to 107.198.255.254107.198.255.25565,534
200107.199.0.0/16107.199.0.1 to 107.199.255.254107.199.255.25565,534
201107.200.0.0/16107.200.0.1 to 107.200.255.254107.200.255.25565,534
202107.201.0.0/16107.201.0.1 to 107.201.255.254107.201.255.25565,534
203107.202.0.0/16107.202.0.1 to 107.202.255.254107.202.255.25565,534
204107.203.0.0/16107.203.0.1 to 107.203.255.254107.203.255.25565,534
205107.204.0.0/16107.204.0.1 to 107.204.255.254107.204.255.25565,534
206107.205.0.0/16107.205.0.1 to 107.205.255.254107.205.255.25565,534
207107.206.0.0/16107.206.0.1 to 107.206.255.254107.206.255.25565,534
208107.207.0.0/16107.207.0.1 to 107.207.255.254107.207.255.25565,534
209107.208.0.0/16107.208.0.1 to 107.208.255.254107.208.255.25565,534
210107.209.0.0/16107.209.0.1 to 107.209.255.254107.209.255.25565,534
211107.210.0.0/16107.210.0.1 to 107.210.255.254107.210.255.25565,534
212107.211.0.0/16107.211.0.1 to 107.211.255.254107.211.255.25565,534
213107.212.0.0/16107.212.0.1 to 107.212.255.254107.212.255.25565,534
214107.213.0.0/16107.213.0.1 to 107.213.255.254107.213.255.25565,534
215107.214.0.0/16107.214.0.1 to 107.214.255.254107.214.255.25565,534
216107.215.0.0/16107.215.0.1 to 107.215.255.254107.215.255.25565,534
217107.216.0.0/16107.216.0.1 to 107.216.255.254107.216.255.25565,534
218107.217.0.0/16107.217.0.1 to 107.217.255.254107.217.255.25565,534
219107.218.0.0/16107.218.0.1 to 107.218.255.254107.218.255.25565,534
220107.219.0.0/16107.219.0.1 to 107.219.255.254107.219.255.25565,534
221107.220.0.0/16107.220.0.1 to 107.220.255.254107.220.255.25565,534
222107.221.0.0/16107.221.0.1 to 107.221.255.254107.221.255.25565,534
223107.222.0.0/16107.222.0.1 to 107.222.255.254107.222.255.25565,534
224107.223.0.0/16107.223.0.1 to 107.223.255.254107.223.255.25565,534
225107.224.0.0/16107.224.0.1 to 107.224.255.254107.224.255.25565,534
226107.225.0.0/16107.225.0.1 to 107.225.255.254107.225.255.25565,534
227107.226.0.0/16107.226.0.1 to 107.226.255.254107.226.255.25565,534
228107.227.0.0/16107.227.0.1 to 107.227.255.254107.227.255.25565,534
229107.228.0.0/16107.228.0.1 to 107.228.255.254107.228.255.25565,534
230107.229.0.0/16107.229.0.1 to 107.229.255.254107.229.255.25565,534
231107.230.0.0/16107.230.0.1 to 107.230.255.254107.230.255.25565,534
232107.231.0.0/16107.231.0.1 to 107.231.255.254107.231.255.25565,534
233107.232.0.0/16107.232.0.1 to 107.232.255.254107.232.255.25565,534
234107.233.0.0/16107.233.0.1 to 107.233.255.254107.233.255.25565,534
235107.234.0.0/16107.234.0.1 to 107.234.255.254107.234.255.25565,534
236107.235.0.0/16107.235.0.1 to 107.235.255.254107.235.255.25565,534
237107.236.0.0/16107.236.0.1 to 107.236.255.254107.236.255.25565,534
238107.237.0.0/16107.237.0.1 to 107.237.255.254107.237.255.25565,534
239107.238.0.0/16107.238.0.1 to 107.238.255.254107.238.255.25565,534
240107.239.0.0/16107.239.0.1 to 107.239.255.254107.239.255.25565,534
241107.240.0.0/16107.240.0.1 to 107.240.255.254107.240.255.25565,534
242107.241.0.0/16107.241.0.1 to 107.241.255.254107.241.255.25565,534
243107.242.0.0/16107.242.0.1 to 107.242.255.254107.242.255.25565,534
244107.243.0.0/16107.243.0.1 to 107.243.255.254107.243.255.25565,534
245107.244.0.0/16107.244.0.1 to 107.244.255.254107.244.255.25565,534
246107.245.0.0/16107.245.0.1 to 107.245.255.254107.245.255.25565,534
247107.246.0.0/16107.246.0.1 to 107.246.255.254107.246.255.25565,534
248107.247.0.0/16107.247.0.1 to 107.247.255.254107.247.255.25565,534
249107.248.0.0/16107.248.0.1 to 107.248.255.254107.248.255.25565,534
250107.249.0.0/16107.249.0.1 to 107.249.255.254107.249.255.25565,534
251107.250.0.0/16107.250.0.1 to 107.250.255.254107.250.255.25565,534
252107.251.0.0/16107.251.0.1 to 107.251.255.254107.251.255.25565,534
253107.252.0.0/16107.252.0.1 to 107.252.255.254107.252.255.25565,534
254107.253.0.0/16107.253.0.1 to 107.253.255.254107.253.255.25565,534
255107.254.0.0/16107.254.0.1 to 107.254.255.254107.254.255.25565,534
256107.255.0.0/16107.255.0.1 to 107.255.255.254107.255.255.25565,534

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.