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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.

Network151.232.0.0/14
Usable hosts262,142
Subnet mask255.252.0.0
Addresses262,144
Network address
151.232.0.0
Broadcast address
151.235.255.255
First usable
151.232.0.1
Last usable
151.235.255.254
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
B (default /16)
As numbers
Hex 97E80000 · Integer 2548563968 to 2548826111
Reverse DNS zones
232.151.in-addr.arpa
233.151.in-addr.arpa
234.151.in-addr.arpa
235.151.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
Address10010111.11101000.00000000.00000000151.232.0.0
Subnet mask11111111.11111100.00000000.00000000255.252.0.0
Network10010111.11101000.00000000.00000000151.232.0.0
Broadcast10010111.11101011.11111111.11111111151.235.255.255
Split into smaller subnets/26
/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)

151.232.0.0/14 makes 4,096 subnets of /26; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1151.232.0.0/26151.232.0.1 to 151.232.0.62151.232.0.6362
2151.232.0.64/26151.232.0.65 to 151.232.0.126151.232.0.12762
3151.232.0.128/26151.232.0.129 to 151.232.0.190151.232.0.19162
4151.232.0.192/26151.232.0.193 to 151.232.0.254151.232.0.25562
5151.232.1.0/26151.232.1.1 to 151.232.1.62151.232.1.6362
6151.232.1.64/26151.232.1.65 to 151.232.1.126151.232.1.12762
7151.232.1.128/26151.232.1.129 to 151.232.1.190151.232.1.19162
8151.232.1.192/26151.232.1.193 to 151.232.1.254151.232.1.25562
9151.232.2.0/26151.232.2.1 to 151.232.2.62151.232.2.6362
10151.232.2.64/26151.232.2.65 to 151.232.2.126151.232.2.12762
11151.232.2.128/26151.232.2.129 to 151.232.2.190151.232.2.19162
12151.232.2.192/26151.232.2.193 to 151.232.2.254151.232.2.25562
13151.232.3.0/26151.232.3.1 to 151.232.3.62151.232.3.6362
14151.232.3.64/26151.232.3.65 to 151.232.3.126151.232.3.12762
15151.232.3.128/26151.232.3.129 to 151.232.3.190151.232.3.19162
16151.232.3.192/26151.232.3.193 to 151.232.3.254151.232.3.25562
17151.232.4.0/26151.232.4.1 to 151.232.4.62151.232.4.6362
18151.232.4.64/26151.232.4.65 to 151.232.4.126151.232.4.12762
19151.232.4.128/26151.232.4.129 to 151.232.4.190151.232.4.19162
20151.232.4.192/26151.232.4.193 to 151.232.4.254151.232.4.25562
21151.232.5.0/26151.232.5.1 to 151.232.5.62151.232.5.6362
22151.232.5.64/26151.232.5.65 to 151.232.5.126151.232.5.12762
23151.232.5.128/26151.232.5.129 to 151.232.5.190151.232.5.19162
24151.232.5.192/26151.232.5.193 to 151.232.5.254151.232.5.25562
25151.232.6.0/26151.232.6.1 to 151.232.6.62151.232.6.6362
26151.232.6.64/26151.232.6.65 to 151.232.6.126151.232.6.12762
27151.232.6.128/26151.232.6.129 to 151.232.6.190151.232.6.19162
28151.232.6.192/26151.232.6.193 to 151.232.6.254151.232.6.25562
29151.232.7.0/26151.232.7.1 to 151.232.7.62151.232.7.6362
30151.232.7.64/26151.232.7.65 to 151.232.7.126151.232.7.12762
31151.232.7.128/26151.232.7.129 to 151.232.7.190151.232.7.19162
32151.232.7.192/26151.232.7.193 to 151.232.7.254151.232.7.25562
33151.232.8.0/26151.232.8.1 to 151.232.8.62151.232.8.6362
34151.232.8.64/26151.232.8.65 to 151.232.8.126151.232.8.12762
35151.232.8.128/26151.232.8.129 to 151.232.8.190151.232.8.19162
36151.232.8.192/26151.232.8.193 to 151.232.8.254151.232.8.25562
37151.232.9.0/26151.232.9.1 to 151.232.9.62151.232.9.6362
38151.232.9.64/26151.232.9.65 to 151.232.9.126151.232.9.12762
39151.232.9.128/26151.232.9.129 to 151.232.9.190151.232.9.19162
40151.232.9.192/26151.232.9.193 to 151.232.9.254151.232.9.25562
41151.232.10.0/26151.232.10.1 to 151.232.10.62151.232.10.6362
42151.232.10.64/26151.232.10.65 to 151.232.10.126151.232.10.12762
43151.232.10.128/26151.232.10.129 to 151.232.10.190151.232.10.19162
44151.232.10.192/26151.232.10.193 to 151.232.10.254151.232.10.25562
45151.232.11.0/26151.232.11.1 to 151.232.11.62151.232.11.6362
46151.232.11.64/26151.232.11.65 to 151.232.11.126151.232.11.12762
47151.232.11.128/26151.232.11.129 to 151.232.11.190151.232.11.19162
48151.232.11.192/26151.232.11.193 to 151.232.11.254151.232.11.25562
49151.232.12.0/26151.232.12.1 to 151.232.12.62151.232.12.6362
50151.232.12.64/26151.232.12.65 to 151.232.12.126151.232.12.12762
51151.232.12.128/26151.232.12.129 to 151.232.12.190151.232.12.19162
52151.232.12.192/26151.232.12.193 to 151.232.12.254151.232.12.25562
53151.232.13.0/26151.232.13.1 to 151.232.13.62151.232.13.6362
54151.232.13.64/26151.232.13.65 to 151.232.13.126151.232.13.12762
55151.232.13.128/26151.232.13.129 to 151.232.13.190151.232.13.19162
56151.232.13.192/26151.232.13.193 to 151.232.13.254151.232.13.25562
57151.232.14.0/26151.232.14.1 to 151.232.14.62151.232.14.6362
58151.232.14.64/26151.232.14.65 to 151.232.14.126151.232.14.12762
59151.232.14.128/26151.232.14.129 to 151.232.14.190151.232.14.19162
60151.232.14.192/26151.232.14.193 to 151.232.14.254151.232.14.25562
61151.232.15.0/26151.232.15.1 to 151.232.15.62151.232.15.6362
62151.232.15.64/26151.232.15.65 to 151.232.15.126151.232.15.12762
63151.232.15.128/26151.232.15.129 to 151.232.15.190151.232.15.19162
64151.232.15.192/26151.232.15.193 to 151.232.15.254151.232.15.25562
65151.232.16.0/26151.232.16.1 to 151.232.16.62151.232.16.6362
66151.232.16.64/26151.232.16.65 to 151.232.16.126151.232.16.12762
67151.232.16.128/26151.232.16.129 to 151.232.16.190151.232.16.19162
68151.232.16.192/26151.232.16.193 to 151.232.16.254151.232.16.25562
69151.232.17.0/26151.232.17.1 to 151.232.17.62151.232.17.6362
70151.232.17.64/26151.232.17.65 to 151.232.17.126151.232.17.12762
71151.232.17.128/26151.232.17.129 to 151.232.17.190151.232.17.19162
72151.232.17.192/26151.232.17.193 to 151.232.17.254151.232.17.25562
73151.232.18.0/26151.232.18.1 to 151.232.18.62151.232.18.6362
74151.232.18.64/26151.232.18.65 to 151.232.18.126151.232.18.12762
75151.232.18.128/26151.232.18.129 to 151.232.18.190151.232.18.19162
76151.232.18.192/26151.232.18.193 to 151.232.18.254151.232.18.25562
77151.232.19.0/26151.232.19.1 to 151.232.19.62151.232.19.6362
78151.232.19.64/26151.232.19.65 to 151.232.19.126151.232.19.12762
79151.232.19.128/26151.232.19.129 to 151.232.19.190151.232.19.19162
80151.232.19.192/26151.232.19.193 to 151.232.19.254151.232.19.25562
81151.232.20.0/26151.232.20.1 to 151.232.20.62151.232.20.6362
82151.232.20.64/26151.232.20.65 to 151.232.20.126151.232.20.12762
83151.232.20.128/26151.232.20.129 to 151.232.20.190151.232.20.19162
84151.232.20.192/26151.232.20.193 to 151.232.20.254151.232.20.25562
85151.232.21.0/26151.232.21.1 to 151.232.21.62151.232.21.6362
86151.232.21.64/26151.232.21.65 to 151.232.21.126151.232.21.12762
87151.232.21.128/26151.232.21.129 to 151.232.21.190151.232.21.19162
88151.232.21.192/26151.232.21.193 to 151.232.21.254151.232.21.25562
89151.232.22.0/26151.232.22.1 to 151.232.22.62151.232.22.6362
90151.232.22.64/26151.232.22.65 to 151.232.22.126151.232.22.12762
91151.232.22.128/26151.232.22.129 to 151.232.22.190151.232.22.19162
92151.232.22.192/26151.232.22.193 to 151.232.22.254151.232.22.25562
93151.232.23.0/26151.232.23.1 to 151.232.23.62151.232.23.6362
94151.232.23.64/26151.232.23.65 to 151.232.23.126151.232.23.12762
95151.232.23.128/26151.232.23.129 to 151.232.23.190151.232.23.19162
96151.232.23.192/26151.232.23.193 to 151.232.23.254151.232.23.25562
97151.232.24.0/26151.232.24.1 to 151.232.24.62151.232.24.6362
98151.232.24.64/26151.232.24.65 to 151.232.24.126151.232.24.12762
99151.232.24.128/26151.232.24.129 to 151.232.24.190151.232.24.19162
100151.232.24.192/26151.232.24.193 to 151.232.24.254151.232.24.25562
101151.232.25.0/26151.232.25.1 to 151.232.25.62151.232.25.6362
102151.232.25.64/26151.232.25.65 to 151.232.25.126151.232.25.12762
103151.232.25.128/26151.232.25.129 to 151.232.25.190151.232.25.19162
104151.232.25.192/26151.232.25.193 to 151.232.25.254151.232.25.25562
105151.232.26.0/26151.232.26.1 to 151.232.26.62151.232.26.6362
106151.232.26.64/26151.232.26.65 to 151.232.26.126151.232.26.12762
107151.232.26.128/26151.232.26.129 to 151.232.26.190151.232.26.19162
108151.232.26.192/26151.232.26.193 to 151.232.26.254151.232.26.25562
109151.232.27.0/26151.232.27.1 to 151.232.27.62151.232.27.6362
110151.232.27.64/26151.232.27.65 to 151.232.27.126151.232.27.12762
111151.232.27.128/26151.232.27.129 to 151.232.27.190151.232.27.19162
112151.232.27.192/26151.232.27.193 to 151.232.27.254151.232.27.25562
113151.232.28.0/26151.232.28.1 to 151.232.28.62151.232.28.6362
114151.232.28.64/26151.232.28.65 to 151.232.28.126151.232.28.12762
115151.232.28.128/26151.232.28.129 to 151.232.28.190151.232.28.19162
116151.232.28.192/26151.232.28.193 to 151.232.28.254151.232.28.25562
117151.232.29.0/26151.232.29.1 to 151.232.29.62151.232.29.6362
118151.232.29.64/26151.232.29.65 to 151.232.29.126151.232.29.12762
119151.232.29.128/26151.232.29.129 to 151.232.29.190151.232.29.19162
120151.232.29.192/26151.232.29.193 to 151.232.29.254151.232.29.25562
121151.232.30.0/26151.232.30.1 to 151.232.30.62151.232.30.6362
122151.232.30.64/26151.232.30.65 to 151.232.30.126151.232.30.12762
123151.232.30.128/26151.232.30.129 to 151.232.30.190151.232.30.19162
124151.232.30.192/26151.232.30.193 to 151.232.30.254151.232.30.25562
125151.232.31.0/26151.232.31.1 to 151.232.31.62151.232.31.6362
126151.232.31.64/26151.232.31.65 to 151.232.31.126151.232.31.12762
127151.232.31.128/26151.232.31.129 to 151.232.31.190151.232.31.19162
128151.232.31.192/26151.232.31.193 to 151.232.31.254151.232.31.25562
129151.232.32.0/26151.232.32.1 to 151.232.32.62151.232.32.6362
130151.232.32.64/26151.232.32.65 to 151.232.32.126151.232.32.12762
131151.232.32.128/26151.232.32.129 to 151.232.32.190151.232.32.19162
132151.232.32.192/26151.232.32.193 to 151.232.32.254151.232.32.25562
133151.232.33.0/26151.232.33.1 to 151.232.33.62151.232.33.6362
134151.232.33.64/26151.232.33.65 to 151.232.33.126151.232.33.12762
135151.232.33.128/26151.232.33.129 to 151.232.33.190151.232.33.19162
136151.232.33.192/26151.232.33.193 to 151.232.33.254151.232.33.25562
137151.232.34.0/26151.232.34.1 to 151.232.34.62151.232.34.6362
138151.232.34.64/26151.232.34.65 to 151.232.34.126151.232.34.12762
139151.232.34.128/26151.232.34.129 to 151.232.34.190151.232.34.19162
140151.232.34.192/26151.232.34.193 to 151.232.34.254151.232.34.25562
141151.232.35.0/26151.232.35.1 to 151.232.35.62151.232.35.6362
142151.232.35.64/26151.232.35.65 to 151.232.35.126151.232.35.12762
143151.232.35.128/26151.232.35.129 to 151.232.35.190151.232.35.19162
144151.232.35.192/26151.232.35.193 to 151.232.35.254151.232.35.25562
145151.232.36.0/26151.232.36.1 to 151.232.36.62151.232.36.6362
146151.232.36.64/26151.232.36.65 to 151.232.36.126151.232.36.12762
147151.232.36.128/26151.232.36.129 to 151.232.36.190151.232.36.19162
148151.232.36.192/26151.232.36.193 to 151.232.36.254151.232.36.25562
149151.232.37.0/26151.232.37.1 to 151.232.37.62151.232.37.6362
150151.232.37.64/26151.232.37.65 to 151.232.37.126151.232.37.12762
151151.232.37.128/26151.232.37.129 to 151.232.37.190151.232.37.19162
152151.232.37.192/26151.232.37.193 to 151.232.37.254151.232.37.25562
153151.232.38.0/26151.232.38.1 to 151.232.38.62151.232.38.6362
154151.232.38.64/26151.232.38.65 to 151.232.38.126151.232.38.12762
155151.232.38.128/26151.232.38.129 to 151.232.38.190151.232.38.19162
156151.232.38.192/26151.232.38.193 to 151.232.38.254151.232.38.25562
157151.232.39.0/26151.232.39.1 to 151.232.39.62151.232.39.6362
158151.232.39.64/26151.232.39.65 to 151.232.39.126151.232.39.12762
159151.232.39.128/26151.232.39.129 to 151.232.39.190151.232.39.19162
160151.232.39.192/26151.232.39.193 to 151.232.39.254151.232.39.25562
161151.232.40.0/26151.232.40.1 to 151.232.40.62151.232.40.6362
162151.232.40.64/26151.232.40.65 to 151.232.40.126151.232.40.12762
163151.232.40.128/26151.232.40.129 to 151.232.40.190151.232.40.19162
164151.232.40.192/26151.232.40.193 to 151.232.40.254151.232.40.25562
165151.232.41.0/26151.232.41.1 to 151.232.41.62151.232.41.6362
166151.232.41.64/26151.232.41.65 to 151.232.41.126151.232.41.12762
167151.232.41.128/26151.232.41.129 to 151.232.41.190151.232.41.19162
168151.232.41.192/26151.232.41.193 to 151.232.41.254151.232.41.25562
169151.232.42.0/26151.232.42.1 to 151.232.42.62151.232.42.6362
170151.232.42.64/26151.232.42.65 to 151.232.42.126151.232.42.12762
171151.232.42.128/26151.232.42.129 to 151.232.42.190151.232.42.19162
172151.232.42.192/26151.232.42.193 to 151.232.42.254151.232.42.25562
173151.232.43.0/26151.232.43.1 to 151.232.43.62151.232.43.6362
174151.232.43.64/26151.232.43.65 to 151.232.43.126151.232.43.12762
175151.232.43.128/26151.232.43.129 to 151.232.43.190151.232.43.19162
176151.232.43.192/26151.232.43.193 to 151.232.43.254151.232.43.25562
177151.232.44.0/26151.232.44.1 to 151.232.44.62151.232.44.6362
178151.232.44.64/26151.232.44.65 to 151.232.44.126151.232.44.12762
179151.232.44.128/26151.232.44.129 to 151.232.44.190151.232.44.19162
180151.232.44.192/26151.232.44.193 to 151.232.44.254151.232.44.25562
181151.232.45.0/26151.232.45.1 to 151.232.45.62151.232.45.6362
182151.232.45.64/26151.232.45.65 to 151.232.45.126151.232.45.12762
183151.232.45.128/26151.232.45.129 to 151.232.45.190151.232.45.19162
184151.232.45.192/26151.232.45.193 to 151.232.45.254151.232.45.25562
185151.232.46.0/26151.232.46.1 to 151.232.46.62151.232.46.6362
186151.232.46.64/26151.232.46.65 to 151.232.46.126151.232.46.12762
187151.232.46.128/26151.232.46.129 to 151.232.46.190151.232.46.19162
188151.232.46.192/26151.232.46.193 to 151.232.46.254151.232.46.25562
189151.232.47.0/26151.232.47.1 to 151.232.47.62151.232.47.6362
190151.232.47.64/26151.232.47.65 to 151.232.47.126151.232.47.12762
191151.232.47.128/26151.232.47.129 to 151.232.47.190151.232.47.19162
192151.232.47.192/26151.232.47.193 to 151.232.47.254151.232.47.25562
193151.232.48.0/26151.232.48.1 to 151.232.48.62151.232.48.6362
194151.232.48.64/26151.232.48.65 to 151.232.48.126151.232.48.12762
195151.232.48.128/26151.232.48.129 to 151.232.48.190151.232.48.19162
196151.232.48.192/26151.232.48.193 to 151.232.48.254151.232.48.25562
197151.232.49.0/26151.232.49.1 to 151.232.49.62151.232.49.6362
198151.232.49.64/26151.232.49.65 to 151.232.49.126151.232.49.12762
199151.232.49.128/26151.232.49.129 to 151.232.49.190151.232.49.19162
200151.232.49.192/26151.232.49.193 to 151.232.49.254151.232.49.25562
201151.232.50.0/26151.232.50.1 to 151.232.50.62151.232.50.6362
202151.232.50.64/26151.232.50.65 to 151.232.50.126151.232.50.12762
203151.232.50.128/26151.232.50.129 to 151.232.50.190151.232.50.19162
204151.232.50.192/26151.232.50.193 to 151.232.50.254151.232.50.25562
205151.232.51.0/26151.232.51.1 to 151.232.51.62151.232.51.6362
206151.232.51.64/26151.232.51.65 to 151.232.51.126151.232.51.12762
207151.232.51.128/26151.232.51.129 to 151.232.51.190151.232.51.19162
208151.232.51.192/26151.232.51.193 to 151.232.51.254151.232.51.25562
209151.232.52.0/26151.232.52.1 to 151.232.52.62151.232.52.6362
210151.232.52.64/26151.232.52.65 to 151.232.52.126151.232.52.12762
211151.232.52.128/26151.232.52.129 to 151.232.52.190151.232.52.19162
212151.232.52.192/26151.232.52.193 to 151.232.52.254151.232.52.25562
213151.232.53.0/26151.232.53.1 to 151.232.53.62151.232.53.6362
214151.232.53.64/26151.232.53.65 to 151.232.53.126151.232.53.12762
215151.232.53.128/26151.232.53.129 to 151.232.53.190151.232.53.19162
216151.232.53.192/26151.232.53.193 to 151.232.53.254151.232.53.25562
217151.232.54.0/26151.232.54.1 to 151.232.54.62151.232.54.6362
218151.232.54.64/26151.232.54.65 to 151.232.54.126151.232.54.12762
219151.232.54.128/26151.232.54.129 to 151.232.54.190151.232.54.19162
220151.232.54.192/26151.232.54.193 to 151.232.54.254151.232.54.25562
221151.232.55.0/26151.232.55.1 to 151.232.55.62151.232.55.6362
222151.232.55.64/26151.232.55.65 to 151.232.55.126151.232.55.12762
223151.232.55.128/26151.232.55.129 to 151.232.55.190151.232.55.19162
224151.232.55.192/26151.232.55.193 to 151.232.55.254151.232.55.25562
225151.232.56.0/26151.232.56.1 to 151.232.56.62151.232.56.6362
226151.232.56.64/26151.232.56.65 to 151.232.56.126151.232.56.12762
227151.232.56.128/26151.232.56.129 to 151.232.56.190151.232.56.19162
228151.232.56.192/26151.232.56.193 to 151.232.56.254151.232.56.25562
229151.232.57.0/26151.232.57.1 to 151.232.57.62151.232.57.6362
230151.232.57.64/26151.232.57.65 to 151.232.57.126151.232.57.12762
231151.232.57.128/26151.232.57.129 to 151.232.57.190151.232.57.19162
232151.232.57.192/26151.232.57.193 to 151.232.57.254151.232.57.25562
233151.232.58.0/26151.232.58.1 to 151.232.58.62151.232.58.6362
234151.232.58.64/26151.232.58.65 to 151.232.58.126151.232.58.12762
235151.232.58.128/26151.232.58.129 to 151.232.58.190151.232.58.19162
236151.232.58.192/26151.232.58.193 to 151.232.58.254151.232.58.25562
237151.232.59.0/26151.232.59.1 to 151.232.59.62151.232.59.6362
238151.232.59.64/26151.232.59.65 to 151.232.59.126151.232.59.12762
239151.232.59.128/26151.232.59.129 to 151.232.59.190151.232.59.19162
240151.232.59.192/26151.232.59.193 to 151.232.59.254151.232.59.25562
241151.232.60.0/26151.232.60.1 to 151.232.60.62151.232.60.6362
242151.232.60.64/26151.232.60.65 to 151.232.60.126151.232.60.12762
243151.232.60.128/26151.232.60.129 to 151.232.60.190151.232.60.19162
244151.232.60.192/26151.232.60.193 to 151.232.60.254151.232.60.25562
245151.232.61.0/26151.232.61.1 to 151.232.61.62151.232.61.6362
246151.232.61.64/26151.232.61.65 to 151.232.61.126151.232.61.12762
247151.232.61.128/26151.232.61.129 to 151.232.61.190151.232.61.19162
248151.232.61.192/26151.232.61.193 to 151.232.61.254151.232.61.25562
249151.232.62.0/26151.232.62.1 to 151.232.62.62151.232.62.6362
250151.232.62.64/26151.232.62.65 to 151.232.62.126151.232.62.12762
251151.232.62.128/26151.232.62.129 to 151.232.62.190151.232.62.19162
252151.232.62.192/26151.232.62.193 to 151.232.62.254151.232.62.25562
253151.232.63.0/26151.232.63.1 to 151.232.63.62151.232.63.6362
254151.232.63.64/26151.232.63.65 to 151.232.63.126151.232.63.12762
255151.232.63.128/26151.232.63.129 to 151.232.63.190151.232.63.19162
256151.232.63.192/26151.232.63.193 to 151.232.63.254151.232.63.25562

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.