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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.

Network107.76.0.0/16
Usable hosts65,534
Subnet mask255.255.0.0
Addresses65,536
Network address
107.76.0.0
Broadcast address
107.76.255.255
First usable
107.76.0.1
Last usable
107.76.255.254
Usable hosts
65,534 (65,536 less the network and broadcast addresses)
Subnet mask
255.255.0.0
Wildcard mask
0.0.255.255 (Cisco ACLs, OSPF)
Prefix length
/16
Type
Public public
Old class
A (default /8)
As numbers
Hex 6B4C0000 · Integer 1800142848 to 1800208383
Reverse DNS zone
76.107.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address01101011.01001100..00000000.00000000107.76.0.0
Subnet mask11111111.11111111..00000000.00000000255.255.0.0
Network01101011.01001100..00000000.00000000107.76.0.0
Broadcast01101011.01001100..11111111.11111111107.76.255.255
Split into smaller subnets/26
/17 (2)/18 (4)/19 (8)/20 (16)/21 (32)/22 (64)/23 (128)/24 (256)/25 (512)/26 (1,024)/27 (2,048)/28 (4,096)

107.76.0.0/16 makes 1,024 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1107.76.0.0/26107.76.0.1 to 107.76.0.62107.76.0.6362
2107.76.0.64/26107.76.0.65 to 107.76.0.126107.76.0.12762
3107.76.0.128/26107.76.0.129 to 107.76.0.190107.76.0.19162
4107.76.0.192/26107.76.0.193 to 107.76.0.254107.76.0.25562
5107.76.1.0/26107.76.1.1 to 107.76.1.62107.76.1.6362
6107.76.1.64/26107.76.1.65 to 107.76.1.126107.76.1.12762
7107.76.1.128/26107.76.1.129 to 107.76.1.190107.76.1.19162
8107.76.1.192/26107.76.1.193 to 107.76.1.254107.76.1.25562
9107.76.2.0/26107.76.2.1 to 107.76.2.62107.76.2.6362
10107.76.2.64/26107.76.2.65 to 107.76.2.126107.76.2.12762
11107.76.2.128/26107.76.2.129 to 107.76.2.190107.76.2.19162
12107.76.2.192/26107.76.2.193 to 107.76.2.254107.76.2.25562
13107.76.3.0/26107.76.3.1 to 107.76.3.62107.76.3.6362
14107.76.3.64/26107.76.3.65 to 107.76.3.126107.76.3.12762
15107.76.3.128/26107.76.3.129 to 107.76.3.190107.76.3.19162
16107.76.3.192/26107.76.3.193 to 107.76.3.254107.76.3.25562
17107.76.4.0/26107.76.4.1 to 107.76.4.62107.76.4.6362
18107.76.4.64/26107.76.4.65 to 107.76.4.126107.76.4.12762
19107.76.4.128/26107.76.4.129 to 107.76.4.190107.76.4.19162
20107.76.4.192/26107.76.4.193 to 107.76.4.254107.76.4.25562
21107.76.5.0/26107.76.5.1 to 107.76.5.62107.76.5.6362
22107.76.5.64/26107.76.5.65 to 107.76.5.126107.76.5.12762
23107.76.5.128/26107.76.5.129 to 107.76.5.190107.76.5.19162
24107.76.5.192/26107.76.5.193 to 107.76.5.254107.76.5.25562
25107.76.6.0/26107.76.6.1 to 107.76.6.62107.76.6.6362
26107.76.6.64/26107.76.6.65 to 107.76.6.126107.76.6.12762
27107.76.6.128/26107.76.6.129 to 107.76.6.190107.76.6.19162
28107.76.6.192/26107.76.6.193 to 107.76.6.254107.76.6.25562
29107.76.7.0/26107.76.7.1 to 107.76.7.62107.76.7.6362
30107.76.7.64/26107.76.7.65 to 107.76.7.126107.76.7.12762
31107.76.7.128/26107.76.7.129 to 107.76.7.190107.76.7.19162
32107.76.7.192/26107.76.7.193 to 107.76.7.254107.76.7.25562
33107.76.8.0/26107.76.8.1 to 107.76.8.62107.76.8.6362
34107.76.8.64/26107.76.8.65 to 107.76.8.126107.76.8.12762
35107.76.8.128/26107.76.8.129 to 107.76.8.190107.76.8.19162
36107.76.8.192/26107.76.8.193 to 107.76.8.254107.76.8.25562
37107.76.9.0/26107.76.9.1 to 107.76.9.62107.76.9.6362
38107.76.9.64/26107.76.9.65 to 107.76.9.126107.76.9.12762
39107.76.9.128/26107.76.9.129 to 107.76.9.190107.76.9.19162
40107.76.9.192/26107.76.9.193 to 107.76.9.254107.76.9.25562
41107.76.10.0/26107.76.10.1 to 107.76.10.62107.76.10.6362
42107.76.10.64/26107.76.10.65 to 107.76.10.126107.76.10.12762
43107.76.10.128/26107.76.10.129 to 107.76.10.190107.76.10.19162
44107.76.10.192/26107.76.10.193 to 107.76.10.254107.76.10.25562
45107.76.11.0/26107.76.11.1 to 107.76.11.62107.76.11.6362
46107.76.11.64/26107.76.11.65 to 107.76.11.126107.76.11.12762
47107.76.11.128/26107.76.11.129 to 107.76.11.190107.76.11.19162
48107.76.11.192/26107.76.11.193 to 107.76.11.254107.76.11.25562
49107.76.12.0/26107.76.12.1 to 107.76.12.62107.76.12.6362
50107.76.12.64/26107.76.12.65 to 107.76.12.126107.76.12.12762
51107.76.12.128/26107.76.12.129 to 107.76.12.190107.76.12.19162
52107.76.12.192/26107.76.12.193 to 107.76.12.254107.76.12.25562
53107.76.13.0/26107.76.13.1 to 107.76.13.62107.76.13.6362
54107.76.13.64/26107.76.13.65 to 107.76.13.126107.76.13.12762
55107.76.13.128/26107.76.13.129 to 107.76.13.190107.76.13.19162
56107.76.13.192/26107.76.13.193 to 107.76.13.254107.76.13.25562
57107.76.14.0/26107.76.14.1 to 107.76.14.62107.76.14.6362
58107.76.14.64/26107.76.14.65 to 107.76.14.126107.76.14.12762
59107.76.14.128/26107.76.14.129 to 107.76.14.190107.76.14.19162
60107.76.14.192/26107.76.14.193 to 107.76.14.254107.76.14.25562
61107.76.15.0/26107.76.15.1 to 107.76.15.62107.76.15.6362
62107.76.15.64/26107.76.15.65 to 107.76.15.126107.76.15.12762
63107.76.15.128/26107.76.15.129 to 107.76.15.190107.76.15.19162
64107.76.15.192/26107.76.15.193 to 107.76.15.254107.76.15.25562
65107.76.16.0/26107.76.16.1 to 107.76.16.62107.76.16.6362
66107.76.16.64/26107.76.16.65 to 107.76.16.126107.76.16.12762
67107.76.16.128/26107.76.16.129 to 107.76.16.190107.76.16.19162
68107.76.16.192/26107.76.16.193 to 107.76.16.254107.76.16.25562
69107.76.17.0/26107.76.17.1 to 107.76.17.62107.76.17.6362
70107.76.17.64/26107.76.17.65 to 107.76.17.126107.76.17.12762
71107.76.17.128/26107.76.17.129 to 107.76.17.190107.76.17.19162
72107.76.17.192/26107.76.17.193 to 107.76.17.254107.76.17.25562
73107.76.18.0/26107.76.18.1 to 107.76.18.62107.76.18.6362
74107.76.18.64/26107.76.18.65 to 107.76.18.126107.76.18.12762
75107.76.18.128/26107.76.18.129 to 107.76.18.190107.76.18.19162
76107.76.18.192/26107.76.18.193 to 107.76.18.254107.76.18.25562
77107.76.19.0/26107.76.19.1 to 107.76.19.62107.76.19.6362
78107.76.19.64/26107.76.19.65 to 107.76.19.126107.76.19.12762
79107.76.19.128/26107.76.19.129 to 107.76.19.190107.76.19.19162
80107.76.19.192/26107.76.19.193 to 107.76.19.254107.76.19.25562
81107.76.20.0/26107.76.20.1 to 107.76.20.62107.76.20.6362
82107.76.20.64/26107.76.20.65 to 107.76.20.126107.76.20.12762
83107.76.20.128/26107.76.20.129 to 107.76.20.190107.76.20.19162
84107.76.20.192/26107.76.20.193 to 107.76.20.254107.76.20.25562
85107.76.21.0/26107.76.21.1 to 107.76.21.62107.76.21.6362
86107.76.21.64/26107.76.21.65 to 107.76.21.126107.76.21.12762
87107.76.21.128/26107.76.21.129 to 107.76.21.190107.76.21.19162
88107.76.21.192/26107.76.21.193 to 107.76.21.254107.76.21.25562
89107.76.22.0/26107.76.22.1 to 107.76.22.62107.76.22.6362
90107.76.22.64/26107.76.22.65 to 107.76.22.126107.76.22.12762
91107.76.22.128/26107.76.22.129 to 107.76.22.190107.76.22.19162
92107.76.22.192/26107.76.22.193 to 107.76.22.254107.76.22.25562
93107.76.23.0/26107.76.23.1 to 107.76.23.62107.76.23.6362
94107.76.23.64/26107.76.23.65 to 107.76.23.126107.76.23.12762
95107.76.23.128/26107.76.23.129 to 107.76.23.190107.76.23.19162
96107.76.23.192/26107.76.23.193 to 107.76.23.254107.76.23.25562
97107.76.24.0/26107.76.24.1 to 107.76.24.62107.76.24.6362
98107.76.24.64/26107.76.24.65 to 107.76.24.126107.76.24.12762
99107.76.24.128/26107.76.24.129 to 107.76.24.190107.76.24.19162
100107.76.24.192/26107.76.24.193 to 107.76.24.254107.76.24.25562
101107.76.25.0/26107.76.25.1 to 107.76.25.62107.76.25.6362
102107.76.25.64/26107.76.25.65 to 107.76.25.126107.76.25.12762
103107.76.25.128/26107.76.25.129 to 107.76.25.190107.76.25.19162
104107.76.25.192/26107.76.25.193 to 107.76.25.254107.76.25.25562
105107.76.26.0/26107.76.26.1 to 107.76.26.62107.76.26.6362
106107.76.26.64/26107.76.26.65 to 107.76.26.126107.76.26.12762
107107.76.26.128/26107.76.26.129 to 107.76.26.190107.76.26.19162
108107.76.26.192/26107.76.26.193 to 107.76.26.254107.76.26.25562
109107.76.27.0/26107.76.27.1 to 107.76.27.62107.76.27.6362
110107.76.27.64/26107.76.27.65 to 107.76.27.126107.76.27.12762
111107.76.27.128/26107.76.27.129 to 107.76.27.190107.76.27.19162
112107.76.27.192/26107.76.27.193 to 107.76.27.254107.76.27.25562
113107.76.28.0/26107.76.28.1 to 107.76.28.62107.76.28.6362
114107.76.28.64/26107.76.28.65 to 107.76.28.126107.76.28.12762
115107.76.28.128/26107.76.28.129 to 107.76.28.190107.76.28.19162
116107.76.28.192/26107.76.28.193 to 107.76.28.254107.76.28.25562
117107.76.29.0/26107.76.29.1 to 107.76.29.62107.76.29.6362
118107.76.29.64/26107.76.29.65 to 107.76.29.126107.76.29.12762
119107.76.29.128/26107.76.29.129 to 107.76.29.190107.76.29.19162
120107.76.29.192/26107.76.29.193 to 107.76.29.254107.76.29.25562
121107.76.30.0/26107.76.30.1 to 107.76.30.62107.76.30.6362
122107.76.30.64/26107.76.30.65 to 107.76.30.126107.76.30.12762
123107.76.30.128/26107.76.30.129 to 107.76.30.190107.76.30.19162
124107.76.30.192/26107.76.30.193 to 107.76.30.254107.76.30.25562
125107.76.31.0/26107.76.31.1 to 107.76.31.62107.76.31.6362
126107.76.31.64/26107.76.31.65 to 107.76.31.126107.76.31.12762
127107.76.31.128/26107.76.31.129 to 107.76.31.190107.76.31.19162
128107.76.31.192/26107.76.31.193 to 107.76.31.254107.76.31.25562
129107.76.32.0/26107.76.32.1 to 107.76.32.62107.76.32.6362
130107.76.32.64/26107.76.32.65 to 107.76.32.126107.76.32.12762
131107.76.32.128/26107.76.32.129 to 107.76.32.190107.76.32.19162
132107.76.32.192/26107.76.32.193 to 107.76.32.254107.76.32.25562
133107.76.33.0/26107.76.33.1 to 107.76.33.62107.76.33.6362
134107.76.33.64/26107.76.33.65 to 107.76.33.126107.76.33.12762
135107.76.33.128/26107.76.33.129 to 107.76.33.190107.76.33.19162
136107.76.33.192/26107.76.33.193 to 107.76.33.254107.76.33.25562
137107.76.34.0/26107.76.34.1 to 107.76.34.62107.76.34.6362
138107.76.34.64/26107.76.34.65 to 107.76.34.126107.76.34.12762
139107.76.34.128/26107.76.34.129 to 107.76.34.190107.76.34.19162
140107.76.34.192/26107.76.34.193 to 107.76.34.254107.76.34.25562
141107.76.35.0/26107.76.35.1 to 107.76.35.62107.76.35.6362
142107.76.35.64/26107.76.35.65 to 107.76.35.126107.76.35.12762
143107.76.35.128/26107.76.35.129 to 107.76.35.190107.76.35.19162
144107.76.35.192/26107.76.35.193 to 107.76.35.254107.76.35.25562
145107.76.36.0/26107.76.36.1 to 107.76.36.62107.76.36.6362
146107.76.36.64/26107.76.36.65 to 107.76.36.126107.76.36.12762
147107.76.36.128/26107.76.36.129 to 107.76.36.190107.76.36.19162
148107.76.36.192/26107.76.36.193 to 107.76.36.254107.76.36.25562
149107.76.37.0/26107.76.37.1 to 107.76.37.62107.76.37.6362
150107.76.37.64/26107.76.37.65 to 107.76.37.126107.76.37.12762
151107.76.37.128/26107.76.37.129 to 107.76.37.190107.76.37.19162
152107.76.37.192/26107.76.37.193 to 107.76.37.254107.76.37.25562
153107.76.38.0/26107.76.38.1 to 107.76.38.62107.76.38.6362
154107.76.38.64/26107.76.38.65 to 107.76.38.126107.76.38.12762
155107.76.38.128/26107.76.38.129 to 107.76.38.190107.76.38.19162
156107.76.38.192/26107.76.38.193 to 107.76.38.254107.76.38.25562
157107.76.39.0/26107.76.39.1 to 107.76.39.62107.76.39.6362
158107.76.39.64/26107.76.39.65 to 107.76.39.126107.76.39.12762
159107.76.39.128/26107.76.39.129 to 107.76.39.190107.76.39.19162
160107.76.39.192/26107.76.39.193 to 107.76.39.254107.76.39.25562
161107.76.40.0/26107.76.40.1 to 107.76.40.62107.76.40.6362
162107.76.40.64/26107.76.40.65 to 107.76.40.126107.76.40.12762
163107.76.40.128/26107.76.40.129 to 107.76.40.190107.76.40.19162
164107.76.40.192/26107.76.40.193 to 107.76.40.254107.76.40.25562
165107.76.41.0/26107.76.41.1 to 107.76.41.62107.76.41.6362
166107.76.41.64/26107.76.41.65 to 107.76.41.126107.76.41.12762
167107.76.41.128/26107.76.41.129 to 107.76.41.190107.76.41.19162
168107.76.41.192/26107.76.41.193 to 107.76.41.254107.76.41.25562
169107.76.42.0/26107.76.42.1 to 107.76.42.62107.76.42.6362
170107.76.42.64/26107.76.42.65 to 107.76.42.126107.76.42.12762
171107.76.42.128/26107.76.42.129 to 107.76.42.190107.76.42.19162
172107.76.42.192/26107.76.42.193 to 107.76.42.254107.76.42.25562
173107.76.43.0/26107.76.43.1 to 107.76.43.62107.76.43.6362
174107.76.43.64/26107.76.43.65 to 107.76.43.126107.76.43.12762
175107.76.43.128/26107.76.43.129 to 107.76.43.190107.76.43.19162
176107.76.43.192/26107.76.43.193 to 107.76.43.254107.76.43.25562
177107.76.44.0/26107.76.44.1 to 107.76.44.62107.76.44.6362
178107.76.44.64/26107.76.44.65 to 107.76.44.126107.76.44.12762
179107.76.44.128/26107.76.44.129 to 107.76.44.190107.76.44.19162
180107.76.44.192/26107.76.44.193 to 107.76.44.254107.76.44.25562
181107.76.45.0/26107.76.45.1 to 107.76.45.62107.76.45.6362
182107.76.45.64/26107.76.45.65 to 107.76.45.126107.76.45.12762
183107.76.45.128/26107.76.45.129 to 107.76.45.190107.76.45.19162
184107.76.45.192/26107.76.45.193 to 107.76.45.254107.76.45.25562
185107.76.46.0/26107.76.46.1 to 107.76.46.62107.76.46.6362
186107.76.46.64/26107.76.46.65 to 107.76.46.126107.76.46.12762
187107.76.46.128/26107.76.46.129 to 107.76.46.190107.76.46.19162
188107.76.46.192/26107.76.46.193 to 107.76.46.254107.76.46.25562
189107.76.47.0/26107.76.47.1 to 107.76.47.62107.76.47.6362
190107.76.47.64/26107.76.47.65 to 107.76.47.126107.76.47.12762
191107.76.47.128/26107.76.47.129 to 107.76.47.190107.76.47.19162
192107.76.47.192/26107.76.47.193 to 107.76.47.254107.76.47.25562
193107.76.48.0/26107.76.48.1 to 107.76.48.62107.76.48.6362
194107.76.48.64/26107.76.48.65 to 107.76.48.126107.76.48.12762
195107.76.48.128/26107.76.48.129 to 107.76.48.190107.76.48.19162
196107.76.48.192/26107.76.48.193 to 107.76.48.254107.76.48.25562
197107.76.49.0/26107.76.49.1 to 107.76.49.62107.76.49.6362
198107.76.49.64/26107.76.49.65 to 107.76.49.126107.76.49.12762
199107.76.49.128/26107.76.49.129 to 107.76.49.190107.76.49.19162
200107.76.49.192/26107.76.49.193 to 107.76.49.254107.76.49.25562
201107.76.50.0/26107.76.50.1 to 107.76.50.62107.76.50.6362
202107.76.50.64/26107.76.50.65 to 107.76.50.126107.76.50.12762
203107.76.50.128/26107.76.50.129 to 107.76.50.190107.76.50.19162
204107.76.50.192/26107.76.50.193 to 107.76.50.254107.76.50.25562
205107.76.51.0/26107.76.51.1 to 107.76.51.62107.76.51.6362
206107.76.51.64/26107.76.51.65 to 107.76.51.126107.76.51.12762
207107.76.51.128/26107.76.51.129 to 107.76.51.190107.76.51.19162
208107.76.51.192/26107.76.51.193 to 107.76.51.254107.76.51.25562
209107.76.52.0/26107.76.52.1 to 107.76.52.62107.76.52.6362
210107.76.52.64/26107.76.52.65 to 107.76.52.126107.76.52.12762
211107.76.52.128/26107.76.52.129 to 107.76.52.190107.76.52.19162
212107.76.52.192/26107.76.52.193 to 107.76.52.254107.76.52.25562
213107.76.53.0/26107.76.53.1 to 107.76.53.62107.76.53.6362
214107.76.53.64/26107.76.53.65 to 107.76.53.126107.76.53.12762
215107.76.53.128/26107.76.53.129 to 107.76.53.190107.76.53.19162
216107.76.53.192/26107.76.53.193 to 107.76.53.254107.76.53.25562
217107.76.54.0/26107.76.54.1 to 107.76.54.62107.76.54.6362
218107.76.54.64/26107.76.54.65 to 107.76.54.126107.76.54.12762
219107.76.54.128/26107.76.54.129 to 107.76.54.190107.76.54.19162
220107.76.54.192/26107.76.54.193 to 107.76.54.254107.76.54.25562
221107.76.55.0/26107.76.55.1 to 107.76.55.62107.76.55.6362
222107.76.55.64/26107.76.55.65 to 107.76.55.126107.76.55.12762
223107.76.55.128/26107.76.55.129 to 107.76.55.190107.76.55.19162
224107.76.55.192/26107.76.55.193 to 107.76.55.254107.76.55.25562
225107.76.56.0/26107.76.56.1 to 107.76.56.62107.76.56.6362
226107.76.56.64/26107.76.56.65 to 107.76.56.126107.76.56.12762
227107.76.56.128/26107.76.56.129 to 107.76.56.190107.76.56.19162
228107.76.56.192/26107.76.56.193 to 107.76.56.254107.76.56.25562
229107.76.57.0/26107.76.57.1 to 107.76.57.62107.76.57.6362
230107.76.57.64/26107.76.57.65 to 107.76.57.126107.76.57.12762
231107.76.57.128/26107.76.57.129 to 107.76.57.190107.76.57.19162
232107.76.57.192/26107.76.57.193 to 107.76.57.254107.76.57.25562
233107.76.58.0/26107.76.58.1 to 107.76.58.62107.76.58.6362
234107.76.58.64/26107.76.58.65 to 107.76.58.126107.76.58.12762
235107.76.58.128/26107.76.58.129 to 107.76.58.190107.76.58.19162
236107.76.58.192/26107.76.58.193 to 107.76.58.254107.76.58.25562
237107.76.59.0/26107.76.59.1 to 107.76.59.62107.76.59.6362
238107.76.59.64/26107.76.59.65 to 107.76.59.126107.76.59.12762
239107.76.59.128/26107.76.59.129 to 107.76.59.190107.76.59.19162
240107.76.59.192/26107.76.59.193 to 107.76.59.254107.76.59.25562
241107.76.60.0/26107.76.60.1 to 107.76.60.62107.76.60.6362
242107.76.60.64/26107.76.60.65 to 107.76.60.126107.76.60.12762
243107.76.60.128/26107.76.60.129 to 107.76.60.190107.76.60.19162
244107.76.60.192/26107.76.60.193 to 107.76.60.254107.76.60.25562
245107.76.61.0/26107.76.61.1 to 107.76.61.62107.76.61.6362
246107.76.61.64/26107.76.61.65 to 107.76.61.126107.76.61.12762
247107.76.61.128/26107.76.61.129 to 107.76.61.190107.76.61.19162
248107.76.61.192/26107.76.61.193 to 107.76.61.254107.76.61.25562
249107.76.62.0/26107.76.62.1 to 107.76.62.62107.76.62.6362
250107.76.62.64/26107.76.62.65 to 107.76.62.126107.76.62.12762
251107.76.62.128/26107.76.62.129 to 107.76.62.190107.76.62.19162
252107.76.62.192/26107.76.62.193 to 107.76.62.254107.76.62.25562
253107.76.63.0/26107.76.63.1 to 107.76.63.62107.76.63.6362
254107.76.63.64/26107.76.63.65 to 107.76.63.126107.76.63.12762
255107.76.63.128/26107.76.63.129 to 107.76.63.190107.76.63.19162
256107.76.63.192/26107.76.63.193 to 107.76.63.254107.76.63.25562

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.