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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.

Network107.76.0.0/15
Usable hosts131,070
Subnet mask255.254.0.0
Addresses131,072
Network address
107.76.0.0
Broadcast address
107.77.255.255
First usable
107.76.0.1
Last usable
107.77.255.254
Usable hosts
131,070 (131,072 less the network and broadcast addresses)
Subnet mask
255.254.0.0
Wildcard mask
0.1.255.255 (Cisco ACLs, OSPF)
Prefix length
/15
Type
Public public
Old class
A (default /8)
As numbers
Hex 6B4C0000 · Integer 1800142848 to 1800273919
Reverse DNS zones
76.107.in-addr.arpa
77.107.in-addr.arpa
/15 is not on a 8-bit boundary, so it takes 2 /16 zones.
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01101011.01001100.00000000.00000000107.76.0.0
Subnet mask11111111.11111110.00000000.00000000255.254.0.0
Network01101011.01001100.00000000.00000000107.76.0.0
Broadcast01101011.01001101.11111111.11111111107.77.255.255
Split into smaller subnets/25
/16 (2)/17 (4)/18 (8)/19 (16)/20 (32)/21 (64)/22 (128)/23 (256)/24 (512)/25 (1,024)/26 (2,048)/27 (4,096)

107.76.0.0/15 makes 1,024 subnets of /25; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1107.76.0.0/25107.76.0.1 to 107.76.0.126107.76.0.127126
2107.76.0.128/25107.76.0.129 to 107.76.0.254107.76.0.255126
3107.76.1.0/25107.76.1.1 to 107.76.1.126107.76.1.127126
4107.76.1.128/25107.76.1.129 to 107.76.1.254107.76.1.255126
5107.76.2.0/25107.76.2.1 to 107.76.2.126107.76.2.127126
6107.76.2.128/25107.76.2.129 to 107.76.2.254107.76.2.255126
7107.76.3.0/25107.76.3.1 to 107.76.3.126107.76.3.127126
8107.76.3.128/25107.76.3.129 to 107.76.3.254107.76.3.255126
9107.76.4.0/25107.76.4.1 to 107.76.4.126107.76.4.127126
10107.76.4.128/25107.76.4.129 to 107.76.4.254107.76.4.255126
11107.76.5.0/25107.76.5.1 to 107.76.5.126107.76.5.127126
12107.76.5.128/25107.76.5.129 to 107.76.5.254107.76.5.255126
13107.76.6.0/25107.76.6.1 to 107.76.6.126107.76.6.127126
14107.76.6.128/25107.76.6.129 to 107.76.6.254107.76.6.255126
15107.76.7.0/25107.76.7.1 to 107.76.7.126107.76.7.127126
16107.76.7.128/25107.76.7.129 to 107.76.7.254107.76.7.255126
17107.76.8.0/25107.76.8.1 to 107.76.8.126107.76.8.127126
18107.76.8.128/25107.76.8.129 to 107.76.8.254107.76.8.255126
19107.76.9.0/25107.76.9.1 to 107.76.9.126107.76.9.127126
20107.76.9.128/25107.76.9.129 to 107.76.9.254107.76.9.255126
21107.76.10.0/25107.76.10.1 to 107.76.10.126107.76.10.127126
22107.76.10.128/25107.76.10.129 to 107.76.10.254107.76.10.255126
23107.76.11.0/25107.76.11.1 to 107.76.11.126107.76.11.127126
24107.76.11.128/25107.76.11.129 to 107.76.11.254107.76.11.255126
25107.76.12.0/25107.76.12.1 to 107.76.12.126107.76.12.127126
26107.76.12.128/25107.76.12.129 to 107.76.12.254107.76.12.255126
27107.76.13.0/25107.76.13.1 to 107.76.13.126107.76.13.127126
28107.76.13.128/25107.76.13.129 to 107.76.13.254107.76.13.255126
29107.76.14.0/25107.76.14.1 to 107.76.14.126107.76.14.127126
30107.76.14.128/25107.76.14.129 to 107.76.14.254107.76.14.255126
31107.76.15.0/25107.76.15.1 to 107.76.15.126107.76.15.127126
32107.76.15.128/25107.76.15.129 to 107.76.15.254107.76.15.255126
33107.76.16.0/25107.76.16.1 to 107.76.16.126107.76.16.127126
34107.76.16.128/25107.76.16.129 to 107.76.16.254107.76.16.255126
35107.76.17.0/25107.76.17.1 to 107.76.17.126107.76.17.127126
36107.76.17.128/25107.76.17.129 to 107.76.17.254107.76.17.255126
37107.76.18.0/25107.76.18.1 to 107.76.18.126107.76.18.127126
38107.76.18.128/25107.76.18.129 to 107.76.18.254107.76.18.255126
39107.76.19.0/25107.76.19.1 to 107.76.19.126107.76.19.127126
40107.76.19.128/25107.76.19.129 to 107.76.19.254107.76.19.255126
41107.76.20.0/25107.76.20.1 to 107.76.20.126107.76.20.127126
42107.76.20.128/25107.76.20.129 to 107.76.20.254107.76.20.255126
43107.76.21.0/25107.76.21.1 to 107.76.21.126107.76.21.127126
44107.76.21.128/25107.76.21.129 to 107.76.21.254107.76.21.255126
45107.76.22.0/25107.76.22.1 to 107.76.22.126107.76.22.127126
46107.76.22.128/25107.76.22.129 to 107.76.22.254107.76.22.255126
47107.76.23.0/25107.76.23.1 to 107.76.23.126107.76.23.127126
48107.76.23.128/25107.76.23.129 to 107.76.23.254107.76.23.255126
49107.76.24.0/25107.76.24.1 to 107.76.24.126107.76.24.127126
50107.76.24.128/25107.76.24.129 to 107.76.24.254107.76.24.255126
51107.76.25.0/25107.76.25.1 to 107.76.25.126107.76.25.127126
52107.76.25.128/25107.76.25.129 to 107.76.25.254107.76.25.255126
53107.76.26.0/25107.76.26.1 to 107.76.26.126107.76.26.127126
54107.76.26.128/25107.76.26.129 to 107.76.26.254107.76.26.255126
55107.76.27.0/25107.76.27.1 to 107.76.27.126107.76.27.127126
56107.76.27.128/25107.76.27.129 to 107.76.27.254107.76.27.255126
57107.76.28.0/25107.76.28.1 to 107.76.28.126107.76.28.127126
58107.76.28.128/25107.76.28.129 to 107.76.28.254107.76.28.255126
59107.76.29.0/25107.76.29.1 to 107.76.29.126107.76.29.127126
60107.76.29.128/25107.76.29.129 to 107.76.29.254107.76.29.255126
61107.76.30.0/25107.76.30.1 to 107.76.30.126107.76.30.127126
62107.76.30.128/25107.76.30.129 to 107.76.30.254107.76.30.255126
63107.76.31.0/25107.76.31.1 to 107.76.31.126107.76.31.127126
64107.76.31.128/25107.76.31.129 to 107.76.31.254107.76.31.255126
65107.76.32.0/25107.76.32.1 to 107.76.32.126107.76.32.127126
66107.76.32.128/25107.76.32.129 to 107.76.32.254107.76.32.255126
67107.76.33.0/25107.76.33.1 to 107.76.33.126107.76.33.127126
68107.76.33.128/25107.76.33.129 to 107.76.33.254107.76.33.255126
69107.76.34.0/25107.76.34.1 to 107.76.34.126107.76.34.127126
70107.76.34.128/25107.76.34.129 to 107.76.34.254107.76.34.255126
71107.76.35.0/25107.76.35.1 to 107.76.35.126107.76.35.127126
72107.76.35.128/25107.76.35.129 to 107.76.35.254107.76.35.255126
73107.76.36.0/25107.76.36.1 to 107.76.36.126107.76.36.127126
74107.76.36.128/25107.76.36.129 to 107.76.36.254107.76.36.255126
75107.76.37.0/25107.76.37.1 to 107.76.37.126107.76.37.127126
76107.76.37.128/25107.76.37.129 to 107.76.37.254107.76.37.255126
77107.76.38.0/25107.76.38.1 to 107.76.38.126107.76.38.127126
78107.76.38.128/25107.76.38.129 to 107.76.38.254107.76.38.255126
79107.76.39.0/25107.76.39.1 to 107.76.39.126107.76.39.127126
80107.76.39.128/25107.76.39.129 to 107.76.39.254107.76.39.255126
81107.76.40.0/25107.76.40.1 to 107.76.40.126107.76.40.127126
82107.76.40.128/25107.76.40.129 to 107.76.40.254107.76.40.255126
83107.76.41.0/25107.76.41.1 to 107.76.41.126107.76.41.127126
84107.76.41.128/25107.76.41.129 to 107.76.41.254107.76.41.255126
85107.76.42.0/25107.76.42.1 to 107.76.42.126107.76.42.127126
86107.76.42.128/25107.76.42.129 to 107.76.42.254107.76.42.255126
87107.76.43.0/25107.76.43.1 to 107.76.43.126107.76.43.127126
88107.76.43.128/25107.76.43.129 to 107.76.43.254107.76.43.255126
89107.76.44.0/25107.76.44.1 to 107.76.44.126107.76.44.127126
90107.76.44.128/25107.76.44.129 to 107.76.44.254107.76.44.255126
91107.76.45.0/25107.76.45.1 to 107.76.45.126107.76.45.127126
92107.76.45.128/25107.76.45.129 to 107.76.45.254107.76.45.255126
93107.76.46.0/25107.76.46.1 to 107.76.46.126107.76.46.127126
94107.76.46.128/25107.76.46.129 to 107.76.46.254107.76.46.255126
95107.76.47.0/25107.76.47.1 to 107.76.47.126107.76.47.127126
96107.76.47.128/25107.76.47.129 to 107.76.47.254107.76.47.255126
97107.76.48.0/25107.76.48.1 to 107.76.48.126107.76.48.127126
98107.76.48.128/25107.76.48.129 to 107.76.48.254107.76.48.255126
99107.76.49.0/25107.76.49.1 to 107.76.49.126107.76.49.127126
100107.76.49.128/25107.76.49.129 to 107.76.49.254107.76.49.255126
101107.76.50.0/25107.76.50.1 to 107.76.50.126107.76.50.127126
102107.76.50.128/25107.76.50.129 to 107.76.50.254107.76.50.255126
103107.76.51.0/25107.76.51.1 to 107.76.51.126107.76.51.127126
104107.76.51.128/25107.76.51.129 to 107.76.51.254107.76.51.255126
105107.76.52.0/25107.76.52.1 to 107.76.52.126107.76.52.127126
106107.76.52.128/25107.76.52.129 to 107.76.52.254107.76.52.255126
107107.76.53.0/25107.76.53.1 to 107.76.53.126107.76.53.127126
108107.76.53.128/25107.76.53.129 to 107.76.53.254107.76.53.255126
109107.76.54.0/25107.76.54.1 to 107.76.54.126107.76.54.127126
110107.76.54.128/25107.76.54.129 to 107.76.54.254107.76.54.255126
111107.76.55.0/25107.76.55.1 to 107.76.55.126107.76.55.127126
112107.76.55.128/25107.76.55.129 to 107.76.55.254107.76.55.255126
113107.76.56.0/25107.76.56.1 to 107.76.56.126107.76.56.127126
114107.76.56.128/25107.76.56.129 to 107.76.56.254107.76.56.255126
115107.76.57.0/25107.76.57.1 to 107.76.57.126107.76.57.127126
116107.76.57.128/25107.76.57.129 to 107.76.57.254107.76.57.255126
117107.76.58.0/25107.76.58.1 to 107.76.58.126107.76.58.127126
118107.76.58.128/25107.76.58.129 to 107.76.58.254107.76.58.255126
119107.76.59.0/25107.76.59.1 to 107.76.59.126107.76.59.127126
120107.76.59.128/25107.76.59.129 to 107.76.59.254107.76.59.255126
121107.76.60.0/25107.76.60.1 to 107.76.60.126107.76.60.127126
122107.76.60.128/25107.76.60.129 to 107.76.60.254107.76.60.255126
123107.76.61.0/25107.76.61.1 to 107.76.61.126107.76.61.127126
124107.76.61.128/25107.76.61.129 to 107.76.61.254107.76.61.255126
125107.76.62.0/25107.76.62.1 to 107.76.62.126107.76.62.127126
126107.76.62.128/25107.76.62.129 to 107.76.62.254107.76.62.255126
127107.76.63.0/25107.76.63.1 to 107.76.63.126107.76.63.127126
128107.76.63.128/25107.76.63.129 to 107.76.63.254107.76.63.255126
129107.76.64.0/25107.76.64.1 to 107.76.64.126107.76.64.127126
130107.76.64.128/25107.76.64.129 to 107.76.64.254107.76.64.255126
131107.76.65.0/25107.76.65.1 to 107.76.65.126107.76.65.127126
132107.76.65.128/25107.76.65.129 to 107.76.65.254107.76.65.255126
133107.76.66.0/25107.76.66.1 to 107.76.66.126107.76.66.127126
134107.76.66.128/25107.76.66.129 to 107.76.66.254107.76.66.255126
135107.76.67.0/25107.76.67.1 to 107.76.67.126107.76.67.127126
136107.76.67.128/25107.76.67.129 to 107.76.67.254107.76.67.255126
137107.76.68.0/25107.76.68.1 to 107.76.68.126107.76.68.127126
138107.76.68.128/25107.76.68.129 to 107.76.68.254107.76.68.255126
139107.76.69.0/25107.76.69.1 to 107.76.69.126107.76.69.127126
140107.76.69.128/25107.76.69.129 to 107.76.69.254107.76.69.255126
141107.76.70.0/25107.76.70.1 to 107.76.70.126107.76.70.127126
142107.76.70.128/25107.76.70.129 to 107.76.70.254107.76.70.255126
143107.76.71.0/25107.76.71.1 to 107.76.71.126107.76.71.127126
144107.76.71.128/25107.76.71.129 to 107.76.71.254107.76.71.255126
145107.76.72.0/25107.76.72.1 to 107.76.72.126107.76.72.127126
146107.76.72.128/25107.76.72.129 to 107.76.72.254107.76.72.255126
147107.76.73.0/25107.76.73.1 to 107.76.73.126107.76.73.127126
148107.76.73.128/25107.76.73.129 to 107.76.73.254107.76.73.255126
149107.76.74.0/25107.76.74.1 to 107.76.74.126107.76.74.127126
150107.76.74.128/25107.76.74.129 to 107.76.74.254107.76.74.255126
151107.76.75.0/25107.76.75.1 to 107.76.75.126107.76.75.127126
152107.76.75.128/25107.76.75.129 to 107.76.75.254107.76.75.255126
153107.76.76.0/25107.76.76.1 to 107.76.76.126107.76.76.127126
154107.76.76.128/25107.76.76.129 to 107.76.76.254107.76.76.255126
155107.76.77.0/25107.76.77.1 to 107.76.77.126107.76.77.127126
156107.76.77.128/25107.76.77.129 to 107.76.77.254107.76.77.255126
157107.76.78.0/25107.76.78.1 to 107.76.78.126107.76.78.127126
158107.76.78.128/25107.76.78.129 to 107.76.78.254107.76.78.255126
159107.76.79.0/25107.76.79.1 to 107.76.79.126107.76.79.127126
160107.76.79.128/25107.76.79.129 to 107.76.79.254107.76.79.255126
161107.76.80.0/25107.76.80.1 to 107.76.80.126107.76.80.127126
162107.76.80.128/25107.76.80.129 to 107.76.80.254107.76.80.255126
163107.76.81.0/25107.76.81.1 to 107.76.81.126107.76.81.127126
164107.76.81.128/25107.76.81.129 to 107.76.81.254107.76.81.255126
165107.76.82.0/25107.76.82.1 to 107.76.82.126107.76.82.127126
166107.76.82.128/25107.76.82.129 to 107.76.82.254107.76.82.255126
167107.76.83.0/25107.76.83.1 to 107.76.83.126107.76.83.127126
168107.76.83.128/25107.76.83.129 to 107.76.83.254107.76.83.255126
169107.76.84.0/25107.76.84.1 to 107.76.84.126107.76.84.127126
170107.76.84.128/25107.76.84.129 to 107.76.84.254107.76.84.255126
171107.76.85.0/25107.76.85.1 to 107.76.85.126107.76.85.127126
172107.76.85.128/25107.76.85.129 to 107.76.85.254107.76.85.255126
173107.76.86.0/25107.76.86.1 to 107.76.86.126107.76.86.127126
174107.76.86.128/25107.76.86.129 to 107.76.86.254107.76.86.255126
175107.76.87.0/25107.76.87.1 to 107.76.87.126107.76.87.127126
176107.76.87.128/25107.76.87.129 to 107.76.87.254107.76.87.255126
177107.76.88.0/25107.76.88.1 to 107.76.88.126107.76.88.127126
178107.76.88.128/25107.76.88.129 to 107.76.88.254107.76.88.255126
179107.76.89.0/25107.76.89.1 to 107.76.89.126107.76.89.127126
180107.76.89.128/25107.76.89.129 to 107.76.89.254107.76.89.255126
181107.76.90.0/25107.76.90.1 to 107.76.90.126107.76.90.127126
182107.76.90.128/25107.76.90.129 to 107.76.90.254107.76.90.255126
183107.76.91.0/25107.76.91.1 to 107.76.91.126107.76.91.127126
184107.76.91.128/25107.76.91.129 to 107.76.91.254107.76.91.255126
185107.76.92.0/25107.76.92.1 to 107.76.92.126107.76.92.127126
186107.76.92.128/25107.76.92.129 to 107.76.92.254107.76.92.255126
187107.76.93.0/25107.76.93.1 to 107.76.93.126107.76.93.127126
188107.76.93.128/25107.76.93.129 to 107.76.93.254107.76.93.255126
189107.76.94.0/25107.76.94.1 to 107.76.94.126107.76.94.127126
190107.76.94.128/25107.76.94.129 to 107.76.94.254107.76.94.255126
191107.76.95.0/25107.76.95.1 to 107.76.95.126107.76.95.127126
192107.76.95.128/25107.76.95.129 to 107.76.95.254107.76.95.255126
193107.76.96.0/25107.76.96.1 to 107.76.96.126107.76.96.127126
194107.76.96.128/25107.76.96.129 to 107.76.96.254107.76.96.255126
195107.76.97.0/25107.76.97.1 to 107.76.97.126107.76.97.127126
196107.76.97.128/25107.76.97.129 to 107.76.97.254107.76.97.255126
197107.76.98.0/25107.76.98.1 to 107.76.98.126107.76.98.127126
198107.76.98.128/25107.76.98.129 to 107.76.98.254107.76.98.255126
199107.76.99.0/25107.76.99.1 to 107.76.99.126107.76.99.127126
200107.76.99.128/25107.76.99.129 to 107.76.99.254107.76.99.255126
201107.76.100.0/25107.76.100.1 to 107.76.100.126107.76.100.127126
202107.76.100.128/25107.76.100.129 to 107.76.100.254107.76.100.255126
203107.76.101.0/25107.76.101.1 to 107.76.101.126107.76.101.127126
204107.76.101.128/25107.76.101.129 to 107.76.101.254107.76.101.255126
205107.76.102.0/25107.76.102.1 to 107.76.102.126107.76.102.127126
206107.76.102.128/25107.76.102.129 to 107.76.102.254107.76.102.255126
207107.76.103.0/25107.76.103.1 to 107.76.103.126107.76.103.127126
208107.76.103.128/25107.76.103.129 to 107.76.103.254107.76.103.255126
209107.76.104.0/25107.76.104.1 to 107.76.104.126107.76.104.127126
210107.76.104.128/25107.76.104.129 to 107.76.104.254107.76.104.255126
211107.76.105.0/25107.76.105.1 to 107.76.105.126107.76.105.127126
212107.76.105.128/25107.76.105.129 to 107.76.105.254107.76.105.255126
213107.76.106.0/25107.76.106.1 to 107.76.106.126107.76.106.127126
214107.76.106.128/25107.76.106.129 to 107.76.106.254107.76.106.255126
215107.76.107.0/25107.76.107.1 to 107.76.107.126107.76.107.127126
216107.76.107.128/25107.76.107.129 to 107.76.107.254107.76.107.255126
217107.76.108.0/25107.76.108.1 to 107.76.108.126107.76.108.127126
218107.76.108.128/25107.76.108.129 to 107.76.108.254107.76.108.255126
219107.76.109.0/25107.76.109.1 to 107.76.109.126107.76.109.127126
220107.76.109.128/25107.76.109.129 to 107.76.109.254107.76.109.255126
221107.76.110.0/25107.76.110.1 to 107.76.110.126107.76.110.127126
222107.76.110.128/25107.76.110.129 to 107.76.110.254107.76.110.255126
223107.76.111.0/25107.76.111.1 to 107.76.111.126107.76.111.127126
224107.76.111.128/25107.76.111.129 to 107.76.111.254107.76.111.255126
225107.76.112.0/25107.76.112.1 to 107.76.112.126107.76.112.127126
226107.76.112.128/25107.76.112.129 to 107.76.112.254107.76.112.255126
227107.76.113.0/25107.76.113.1 to 107.76.113.126107.76.113.127126
228107.76.113.128/25107.76.113.129 to 107.76.113.254107.76.113.255126
229107.76.114.0/25107.76.114.1 to 107.76.114.126107.76.114.127126
230107.76.114.128/25107.76.114.129 to 107.76.114.254107.76.114.255126
231107.76.115.0/25107.76.115.1 to 107.76.115.126107.76.115.127126
232107.76.115.128/25107.76.115.129 to 107.76.115.254107.76.115.255126
233107.76.116.0/25107.76.116.1 to 107.76.116.126107.76.116.127126
234107.76.116.128/25107.76.116.129 to 107.76.116.254107.76.116.255126
235107.76.117.0/25107.76.117.1 to 107.76.117.126107.76.117.127126
236107.76.117.128/25107.76.117.129 to 107.76.117.254107.76.117.255126
237107.76.118.0/25107.76.118.1 to 107.76.118.126107.76.118.127126
238107.76.118.128/25107.76.118.129 to 107.76.118.254107.76.118.255126
239107.76.119.0/25107.76.119.1 to 107.76.119.126107.76.119.127126
240107.76.119.128/25107.76.119.129 to 107.76.119.254107.76.119.255126
241107.76.120.0/25107.76.120.1 to 107.76.120.126107.76.120.127126
242107.76.120.128/25107.76.120.129 to 107.76.120.254107.76.120.255126
243107.76.121.0/25107.76.121.1 to 107.76.121.126107.76.121.127126
244107.76.121.128/25107.76.121.129 to 107.76.121.254107.76.121.255126
245107.76.122.0/25107.76.122.1 to 107.76.122.126107.76.122.127126
246107.76.122.128/25107.76.122.129 to 107.76.122.254107.76.122.255126
247107.76.123.0/25107.76.123.1 to 107.76.123.126107.76.123.127126
248107.76.123.128/25107.76.123.129 to 107.76.123.254107.76.123.255126
249107.76.124.0/25107.76.124.1 to 107.76.124.126107.76.124.127126
250107.76.124.128/25107.76.124.129 to 107.76.124.254107.76.124.255126
251107.76.125.0/25107.76.125.1 to 107.76.125.126107.76.125.127126
252107.76.125.128/25107.76.125.129 to 107.76.125.254107.76.125.255126
253107.76.126.0/25107.76.126.1 to 107.76.126.126107.76.126.127126
254107.76.126.128/25107.76.126.129 to 107.76.126.254107.76.126.255126
255107.76.127.0/25107.76.127.1 to 107.76.127.126107.76.127.127126
256107.76.127.128/25107.76.127.129 to 107.76.127.254107.76.127.255126

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.