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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.

Network198.0.0.0/8
Usable hosts16,777,214
Subnet mask255.0.0.0
Addresses16,777,216
Network address
198.0.0.0
Broadcast address
198.255.255.255
First usable
198.0.0.1
Last usable
198.255.255.254
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
C (default /24)
As numbers
Hex C6000000 · Integer 3321888768 to 3338665983
Reverse DNS zone
198.in-addr.arpa
Binary
Binary view
Binary (network bits bold, host bits grey)Dotted
Address11000110..00000000.00000000.00000000198.0.0.0
Subnet mask11111111..00000000.00000000.00000000255.0.0.0
Network11000110..00000000.00000000.00000000198.0.0.0
Broadcast11000110..11111111.11111111.11111111198.255.255.255
Split into smaller subnets/18
/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)

198.0.0.0/8 makes 1,024 subnets of /18; the first 256 are listed.

Subnets
#SubnetUsable hosts rangeBroadcastHosts
1198.0.0.0/18198.0.0.1 to 198.0.63.254198.0.63.25516,382
2198.0.64.0/18198.0.64.1 to 198.0.127.254198.0.127.25516,382
3198.0.128.0/18198.0.128.1 to 198.0.191.254198.0.191.25516,382
4198.0.192.0/18198.0.192.1 to 198.0.255.254198.0.255.25516,382
5198.1.0.0/18198.1.0.1 to 198.1.63.254198.1.63.25516,382
6198.1.64.0/18198.1.64.1 to 198.1.127.254198.1.127.25516,382
7198.1.128.0/18198.1.128.1 to 198.1.191.254198.1.191.25516,382
8198.1.192.0/18198.1.192.1 to 198.1.255.254198.1.255.25516,382
9198.2.0.0/18198.2.0.1 to 198.2.63.254198.2.63.25516,382
10198.2.64.0/18198.2.64.1 to 198.2.127.254198.2.127.25516,382
11198.2.128.0/18198.2.128.1 to 198.2.191.254198.2.191.25516,382
12198.2.192.0/18198.2.192.1 to 198.2.255.254198.2.255.25516,382
13198.3.0.0/18198.3.0.1 to 198.3.63.254198.3.63.25516,382
14198.3.64.0/18198.3.64.1 to 198.3.127.254198.3.127.25516,382
15198.3.128.0/18198.3.128.1 to 198.3.191.254198.3.191.25516,382
16198.3.192.0/18198.3.192.1 to 198.3.255.254198.3.255.25516,382
17198.4.0.0/18198.4.0.1 to 198.4.63.254198.4.63.25516,382
18198.4.64.0/18198.4.64.1 to 198.4.127.254198.4.127.25516,382
19198.4.128.0/18198.4.128.1 to 198.4.191.254198.4.191.25516,382
20198.4.192.0/18198.4.192.1 to 198.4.255.254198.4.255.25516,382
21198.5.0.0/18198.5.0.1 to 198.5.63.254198.5.63.25516,382
22198.5.64.0/18198.5.64.1 to 198.5.127.254198.5.127.25516,382
23198.5.128.0/18198.5.128.1 to 198.5.191.254198.5.191.25516,382
24198.5.192.0/18198.5.192.1 to 198.5.255.254198.5.255.25516,382
25198.6.0.0/18198.6.0.1 to 198.6.63.254198.6.63.25516,382
26198.6.64.0/18198.6.64.1 to 198.6.127.254198.6.127.25516,382
27198.6.128.0/18198.6.128.1 to 198.6.191.254198.6.191.25516,382
28198.6.192.0/18198.6.192.1 to 198.6.255.254198.6.255.25516,382
29198.7.0.0/18198.7.0.1 to 198.7.63.254198.7.63.25516,382
30198.7.64.0/18198.7.64.1 to 198.7.127.254198.7.127.25516,382
31198.7.128.0/18198.7.128.1 to 198.7.191.254198.7.191.25516,382
32198.7.192.0/18198.7.192.1 to 198.7.255.254198.7.255.25516,382
33198.8.0.0/18198.8.0.1 to 198.8.63.254198.8.63.25516,382
34198.8.64.0/18198.8.64.1 to 198.8.127.254198.8.127.25516,382
35198.8.128.0/18198.8.128.1 to 198.8.191.254198.8.191.25516,382
36198.8.192.0/18198.8.192.1 to 198.8.255.254198.8.255.25516,382
37198.9.0.0/18198.9.0.1 to 198.9.63.254198.9.63.25516,382
38198.9.64.0/18198.9.64.1 to 198.9.127.254198.9.127.25516,382
39198.9.128.0/18198.9.128.1 to 198.9.191.254198.9.191.25516,382
40198.9.192.0/18198.9.192.1 to 198.9.255.254198.9.255.25516,382
41198.10.0.0/18198.10.0.1 to 198.10.63.254198.10.63.25516,382
42198.10.64.0/18198.10.64.1 to 198.10.127.254198.10.127.25516,382
43198.10.128.0/18198.10.128.1 to 198.10.191.254198.10.191.25516,382
44198.10.192.0/18198.10.192.1 to 198.10.255.254198.10.255.25516,382
45198.11.0.0/18198.11.0.1 to 198.11.63.254198.11.63.25516,382
46198.11.64.0/18198.11.64.1 to 198.11.127.254198.11.127.25516,382
47198.11.128.0/18198.11.128.1 to 198.11.191.254198.11.191.25516,382
48198.11.192.0/18198.11.192.1 to 198.11.255.254198.11.255.25516,382
49198.12.0.0/18198.12.0.1 to 198.12.63.254198.12.63.25516,382
50198.12.64.0/18198.12.64.1 to 198.12.127.254198.12.127.25516,382
51198.12.128.0/18198.12.128.1 to 198.12.191.254198.12.191.25516,382
52198.12.192.0/18198.12.192.1 to 198.12.255.254198.12.255.25516,382
53198.13.0.0/18198.13.0.1 to 198.13.63.254198.13.63.25516,382
54198.13.64.0/18198.13.64.1 to 198.13.127.254198.13.127.25516,382
55198.13.128.0/18198.13.128.1 to 198.13.191.254198.13.191.25516,382
56198.13.192.0/18198.13.192.1 to 198.13.255.254198.13.255.25516,382
57198.14.0.0/18198.14.0.1 to 198.14.63.254198.14.63.25516,382
58198.14.64.0/18198.14.64.1 to 198.14.127.254198.14.127.25516,382
59198.14.128.0/18198.14.128.1 to 198.14.191.254198.14.191.25516,382
60198.14.192.0/18198.14.192.1 to 198.14.255.254198.14.255.25516,382
61198.15.0.0/18198.15.0.1 to 198.15.63.254198.15.63.25516,382
62198.15.64.0/18198.15.64.1 to 198.15.127.254198.15.127.25516,382
63198.15.128.0/18198.15.128.1 to 198.15.191.254198.15.191.25516,382
64198.15.192.0/18198.15.192.1 to 198.15.255.254198.15.255.25516,382
65198.16.0.0/18198.16.0.1 to 198.16.63.254198.16.63.25516,382
66198.16.64.0/18198.16.64.1 to 198.16.127.254198.16.127.25516,382
67198.16.128.0/18198.16.128.1 to 198.16.191.254198.16.191.25516,382
68198.16.192.0/18198.16.192.1 to 198.16.255.254198.16.255.25516,382
69198.17.0.0/18198.17.0.1 to 198.17.63.254198.17.63.25516,382
70198.17.64.0/18198.17.64.1 to 198.17.127.254198.17.127.25516,382
71198.17.128.0/18198.17.128.1 to 198.17.191.254198.17.191.25516,382
72198.17.192.0/18198.17.192.1 to 198.17.255.254198.17.255.25516,382
73198.18.0.0/18198.18.0.1 to 198.18.63.254198.18.63.25516,382
74198.18.64.0/18198.18.64.1 to 198.18.127.254198.18.127.25516,382
75198.18.128.0/18198.18.128.1 to 198.18.191.254198.18.191.25516,382
76198.18.192.0/18198.18.192.1 to 198.18.255.254198.18.255.25516,382
77198.19.0.0/18198.19.0.1 to 198.19.63.254198.19.63.25516,382
78198.19.64.0/18198.19.64.1 to 198.19.127.254198.19.127.25516,382
79198.19.128.0/18198.19.128.1 to 198.19.191.254198.19.191.25516,382
80198.19.192.0/18198.19.192.1 to 198.19.255.254198.19.255.25516,382
81198.20.0.0/18198.20.0.1 to 198.20.63.254198.20.63.25516,382
82198.20.64.0/18198.20.64.1 to 198.20.127.254198.20.127.25516,382
83198.20.128.0/18198.20.128.1 to 198.20.191.254198.20.191.25516,382
84198.20.192.0/18198.20.192.1 to 198.20.255.254198.20.255.25516,382
85198.21.0.0/18198.21.0.1 to 198.21.63.254198.21.63.25516,382
86198.21.64.0/18198.21.64.1 to 198.21.127.254198.21.127.25516,382
87198.21.128.0/18198.21.128.1 to 198.21.191.254198.21.191.25516,382
88198.21.192.0/18198.21.192.1 to 198.21.255.254198.21.255.25516,382
89198.22.0.0/18198.22.0.1 to 198.22.63.254198.22.63.25516,382
90198.22.64.0/18198.22.64.1 to 198.22.127.254198.22.127.25516,382
91198.22.128.0/18198.22.128.1 to 198.22.191.254198.22.191.25516,382
92198.22.192.0/18198.22.192.1 to 198.22.255.254198.22.255.25516,382
93198.23.0.0/18198.23.0.1 to 198.23.63.254198.23.63.25516,382
94198.23.64.0/18198.23.64.1 to 198.23.127.254198.23.127.25516,382
95198.23.128.0/18198.23.128.1 to 198.23.191.254198.23.191.25516,382
96198.23.192.0/18198.23.192.1 to 198.23.255.254198.23.255.25516,382
97198.24.0.0/18198.24.0.1 to 198.24.63.254198.24.63.25516,382
98198.24.64.0/18198.24.64.1 to 198.24.127.254198.24.127.25516,382
99198.24.128.0/18198.24.128.1 to 198.24.191.254198.24.191.25516,382
100198.24.192.0/18198.24.192.1 to 198.24.255.254198.24.255.25516,382
101198.25.0.0/18198.25.0.1 to 198.25.63.254198.25.63.25516,382
102198.25.64.0/18198.25.64.1 to 198.25.127.254198.25.127.25516,382
103198.25.128.0/18198.25.128.1 to 198.25.191.254198.25.191.25516,382
104198.25.192.0/18198.25.192.1 to 198.25.255.254198.25.255.25516,382
105198.26.0.0/18198.26.0.1 to 198.26.63.254198.26.63.25516,382
106198.26.64.0/18198.26.64.1 to 198.26.127.254198.26.127.25516,382
107198.26.128.0/18198.26.128.1 to 198.26.191.254198.26.191.25516,382
108198.26.192.0/18198.26.192.1 to 198.26.255.254198.26.255.25516,382
109198.27.0.0/18198.27.0.1 to 198.27.63.254198.27.63.25516,382
110198.27.64.0/18198.27.64.1 to 198.27.127.254198.27.127.25516,382
111198.27.128.0/18198.27.128.1 to 198.27.191.254198.27.191.25516,382
112198.27.192.0/18198.27.192.1 to 198.27.255.254198.27.255.25516,382
113198.28.0.0/18198.28.0.1 to 198.28.63.254198.28.63.25516,382
114198.28.64.0/18198.28.64.1 to 198.28.127.254198.28.127.25516,382
115198.28.128.0/18198.28.128.1 to 198.28.191.254198.28.191.25516,382
116198.28.192.0/18198.28.192.1 to 198.28.255.254198.28.255.25516,382
117198.29.0.0/18198.29.0.1 to 198.29.63.254198.29.63.25516,382
118198.29.64.0/18198.29.64.1 to 198.29.127.254198.29.127.25516,382
119198.29.128.0/18198.29.128.1 to 198.29.191.254198.29.191.25516,382
120198.29.192.0/18198.29.192.1 to 198.29.255.254198.29.255.25516,382
121198.30.0.0/18198.30.0.1 to 198.30.63.254198.30.63.25516,382
122198.30.64.0/18198.30.64.1 to 198.30.127.254198.30.127.25516,382
123198.30.128.0/18198.30.128.1 to 198.30.191.254198.30.191.25516,382
124198.30.192.0/18198.30.192.1 to 198.30.255.254198.30.255.25516,382
125198.31.0.0/18198.31.0.1 to 198.31.63.254198.31.63.25516,382
126198.31.64.0/18198.31.64.1 to 198.31.127.254198.31.127.25516,382
127198.31.128.0/18198.31.128.1 to 198.31.191.254198.31.191.25516,382
128198.31.192.0/18198.31.192.1 to 198.31.255.254198.31.255.25516,382
129198.32.0.0/18198.32.0.1 to 198.32.63.254198.32.63.25516,382
130198.32.64.0/18198.32.64.1 to 198.32.127.254198.32.127.25516,382
131198.32.128.0/18198.32.128.1 to 198.32.191.254198.32.191.25516,382
132198.32.192.0/18198.32.192.1 to 198.32.255.254198.32.255.25516,382
133198.33.0.0/18198.33.0.1 to 198.33.63.254198.33.63.25516,382
134198.33.64.0/18198.33.64.1 to 198.33.127.254198.33.127.25516,382
135198.33.128.0/18198.33.128.1 to 198.33.191.254198.33.191.25516,382
136198.33.192.0/18198.33.192.1 to 198.33.255.254198.33.255.25516,382
137198.34.0.0/18198.34.0.1 to 198.34.63.254198.34.63.25516,382
138198.34.64.0/18198.34.64.1 to 198.34.127.254198.34.127.25516,382
139198.34.128.0/18198.34.128.1 to 198.34.191.254198.34.191.25516,382
140198.34.192.0/18198.34.192.1 to 198.34.255.254198.34.255.25516,382
141198.35.0.0/18198.35.0.1 to 198.35.63.254198.35.63.25516,382
142198.35.64.0/18198.35.64.1 to 198.35.127.254198.35.127.25516,382
143198.35.128.0/18198.35.128.1 to 198.35.191.254198.35.191.25516,382
144198.35.192.0/18198.35.192.1 to 198.35.255.254198.35.255.25516,382
145198.36.0.0/18198.36.0.1 to 198.36.63.254198.36.63.25516,382
146198.36.64.0/18198.36.64.1 to 198.36.127.254198.36.127.25516,382
147198.36.128.0/18198.36.128.1 to 198.36.191.254198.36.191.25516,382
148198.36.192.0/18198.36.192.1 to 198.36.255.254198.36.255.25516,382
149198.37.0.0/18198.37.0.1 to 198.37.63.254198.37.63.25516,382
150198.37.64.0/18198.37.64.1 to 198.37.127.254198.37.127.25516,382
151198.37.128.0/18198.37.128.1 to 198.37.191.254198.37.191.25516,382
152198.37.192.0/18198.37.192.1 to 198.37.255.254198.37.255.25516,382
153198.38.0.0/18198.38.0.1 to 198.38.63.254198.38.63.25516,382
154198.38.64.0/18198.38.64.1 to 198.38.127.254198.38.127.25516,382
155198.38.128.0/18198.38.128.1 to 198.38.191.254198.38.191.25516,382
156198.38.192.0/18198.38.192.1 to 198.38.255.254198.38.255.25516,382
157198.39.0.0/18198.39.0.1 to 198.39.63.254198.39.63.25516,382
158198.39.64.0/18198.39.64.1 to 198.39.127.254198.39.127.25516,382
159198.39.128.0/18198.39.128.1 to 198.39.191.254198.39.191.25516,382
160198.39.192.0/18198.39.192.1 to 198.39.255.254198.39.255.25516,382
161198.40.0.0/18198.40.0.1 to 198.40.63.254198.40.63.25516,382
162198.40.64.0/18198.40.64.1 to 198.40.127.254198.40.127.25516,382
163198.40.128.0/18198.40.128.1 to 198.40.191.254198.40.191.25516,382
164198.40.192.0/18198.40.192.1 to 198.40.255.254198.40.255.25516,382
165198.41.0.0/18198.41.0.1 to 198.41.63.254198.41.63.25516,382
166198.41.64.0/18198.41.64.1 to 198.41.127.254198.41.127.25516,382
167198.41.128.0/18198.41.128.1 to 198.41.191.254198.41.191.25516,382
168198.41.192.0/18198.41.192.1 to 198.41.255.254198.41.255.25516,382
169198.42.0.0/18198.42.0.1 to 198.42.63.254198.42.63.25516,382
170198.42.64.0/18198.42.64.1 to 198.42.127.254198.42.127.25516,382
171198.42.128.0/18198.42.128.1 to 198.42.191.254198.42.191.25516,382
172198.42.192.0/18198.42.192.1 to 198.42.255.254198.42.255.25516,382
173198.43.0.0/18198.43.0.1 to 198.43.63.254198.43.63.25516,382
174198.43.64.0/18198.43.64.1 to 198.43.127.254198.43.127.25516,382
175198.43.128.0/18198.43.128.1 to 198.43.191.254198.43.191.25516,382
176198.43.192.0/18198.43.192.1 to 198.43.255.254198.43.255.25516,382
177198.44.0.0/18198.44.0.1 to 198.44.63.254198.44.63.25516,382
178198.44.64.0/18198.44.64.1 to 198.44.127.254198.44.127.25516,382
179198.44.128.0/18198.44.128.1 to 198.44.191.254198.44.191.25516,382
180198.44.192.0/18198.44.192.1 to 198.44.255.254198.44.255.25516,382
181198.45.0.0/18198.45.0.1 to 198.45.63.254198.45.63.25516,382
182198.45.64.0/18198.45.64.1 to 198.45.127.254198.45.127.25516,382
183198.45.128.0/18198.45.128.1 to 198.45.191.254198.45.191.25516,382
184198.45.192.0/18198.45.192.1 to 198.45.255.254198.45.255.25516,382
185198.46.0.0/18198.46.0.1 to 198.46.63.254198.46.63.25516,382
186198.46.64.0/18198.46.64.1 to 198.46.127.254198.46.127.25516,382
187198.46.128.0/18198.46.128.1 to 198.46.191.254198.46.191.25516,382
188198.46.192.0/18198.46.192.1 to 198.46.255.254198.46.255.25516,382
189198.47.0.0/18198.47.0.1 to 198.47.63.254198.47.63.25516,382
190198.47.64.0/18198.47.64.1 to 198.47.127.254198.47.127.25516,382
191198.47.128.0/18198.47.128.1 to 198.47.191.254198.47.191.25516,382
192198.47.192.0/18198.47.192.1 to 198.47.255.254198.47.255.25516,382
193198.48.0.0/18198.48.0.1 to 198.48.63.254198.48.63.25516,382
194198.48.64.0/18198.48.64.1 to 198.48.127.254198.48.127.25516,382
195198.48.128.0/18198.48.128.1 to 198.48.191.254198.48.191.25516,382
196198.48.192.0/18198.48.192.1 to 198.48.255.254198.48.255.25516,382
197198.49.0.0/18198.49.0.1 to 198.49.63.254198.49.63.25516,382
198198.49.64.0/18198.49.64.1 to 198.49.127.254198.49.127.25516,382
199198.49.128.0/18198.49.128.1 to 198.49.191.254198.49.191.25516,382
200198.49.192.0/18198.49.192.1 to 198.49.255.254198.49.255.25516,382
201198.50.0.0/18198.50.0.1 to 198.50.63.254198.50.63.25516,382
202198.50.64.0/18198.50.64.1 to 198.50.127.254198.50.127.25516,382
203198.50.128.0/18198.50.128.1 to 198.50.191.254198.50.191.25516,382
204198.50.192.0/18198.50.192.1 to 198.50.255.254198.50.255.25516,382
205198.51.0.0/18198.51.0.1 to 198.51.63.254198.51.63.25516,382
206198.51.64.0/18198.51.64.1 to 198.51.127.254198.51.127.25516,382
207198.51.128.0/18198.51.128.1 to 198.51.191.254198.51.191.25516,382
208198.51.192.0/18198.51.192.1 to 198.51.255.254198.51.255.25516,382
209198.52.0.0/18198.52.0.1 to 198.52.63.254198.52.63.25516,382
210198.52.64.0/18198.52.64.1 to 198.52.127.254198.52.127.25516,382
211198.52.128.0/18198.52.128.1 to 198.52.191.254198.52.191.25516,382
212198.52.192.0/18198.52.192.1 to 198.52.255.254198.52.255.25516,382
213198.53.0.0/18198.53.0.1 to 198.53.63.254198.53.63.25516,382
214198.53.64.0/18198.53.64.1 to 198.53.127.254198.53.127.25516,382
215198.53.128.0/18198.53.128.1 to 198.53.191.254198.53.191.25516,382
216198.53.192.0/18198.53.192.1 to 198.53.255.254198.53.255.25516,382
217198.54.0.0/18198.54.0.1 to 198.54.63.254198.54.63.25516,382
218198.54.64.0/18198.54.64.1 to 198.54.127.254198.54.127.25516,382
219198.54.128.0/18198.54.128.1 to 198.54.191.254198.54.191.25516,382
220198.54.192.0/18198.54.192.1 to 198.54.255.254198.54.255.25516,382
221198.55.0.0/18198.55.0.1 to 198.55.63.254198.55.63.25516,382
222198.55.64.0/18198.55.64.1 to 198.55.127.254198.55.127.25516,382
223198.55.128.0/18198.55.128.1 to 198.55.191.254198.55.191.25516,382
224198.55.192.0/18198.55.192.1 to 198.55.255.254198.55.255.25516,382
225198.56.0.0/18198.56.0.1 to 198.56.63.254198.56.63.25516,382
226198.56.64.0/18198.56.64.1 to 198.56.127.254198.56.127.25516,382
227198.56.128.0/18198.56.128.1 to 198.56.191.254198.56.191.25516,382
228198.56.192.0/18198.56.192.1 to 198.56.255.254198.56.255.25516,382
229198.57.0.0/18198.57.0.1 to 198.57.63.254198.57.63.25516,382
230198.57.64.0/18198.57.64.1 to 198.57.127.254198.57.127.25516,382
231198.57.128.0/18198.57.128.1 to 198.57.191.254198.57.191.25516,382
232198.57.192.0/18198.57.192.1 to 198.57.255.254198.57.255.25516,382
233198.58.0.0/18198.58.0.1 to 198.58.63.254198.58.63.25516,382
234198.58.64.0/18198.58.64.1 to 198.58.127.254198.58.127.25516,382
235198.58.128.0/18198.58.128.1 to 198.58.191.254198.58.191.25516,382
236198.58.192.0/18198.58.192.1 to 198.58.255.254198.58.255.25516,382
237198.59.0.0/18198.59.0.1 to 198.59.63.254198.59.63.25516,382
238198.59.64.0/18198.59.64.1 to 198.59.127.254198.59.127.25516,382
239198.59.128.0/18198.59.128.1 to 198.59.191.254198.59.191.25516,382
240198.59.192.0/18198.59.192.1 to 198.59.255.254198.59.255.25516,382
241198.60.0.0/18198.60.0.1 to 198.60.63.254198.60.63.25516,382
242198.60.64.0/18198.60.64.1 to 198.60.127.254198.60.127.25516,382
243198.60.128.0/18198.60.128.1 to 198.60.191.254198.60.191.25516,382
244198.60.192.0/18198.60.192.1 to 198.60.255.254198.60.255.25516,382
245198.61.0.0/18198.61.0.1 to 198.61.63.254198.61.63.25516,382
246198.61.64.0/18198.61.64.1 to 198.61.127.254198.61.127.25516,382
247198.61.128.0/18198.61.128.1 to 198.61.191.254198.61.191.25516,382
248198.61.192.0/18198.61.192.1 to 198.61.255.254198.61.255.25516,382
249198.62.0.0/18198.62.0.1 to 198.62.63.254198.62.63.25516,382
250198.62.64.0/18198.62.64.1 to 198.62.127.254198.62.127.25516,382
251198.62.128.0/18198.62.128.1 to 198.62.191.254198.62.191.25516,382
252198.62.192.0/18198.62.192.1 to 198.62.255.254198.62.255.25516,382
253198.63.0.0/18198.63.0.1 to 198.63.63.254198.63.63.25516,382
254198.63.64.0/18198.63.64.1 to 198.63.127.254198.63.127.25516,382
255198.63.128.0/18198.63.128.1 to 198.63.191.254198.63.191.25516,382
256198.63.192.0/18198.63.192.1 to 198.63.255.254198.63.255.25516,382

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.