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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.

Prefix/16
Addresses2^112
/64 networks2^48
Network
ffaa::/16
First address
ffaa::
Last address
ffaa:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
5,192,296,858,534,827,628,530,496,329,220,096 (2^112)
/64 networks (LANs)
281,474,976,710,656 (2^48)
Full form
ffaa:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
a.a.f.f.ip6.arpa
Split into smaller subnets/32
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

ffaa::/16 makes 65,536 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
1ffaa::/32ffaa:0:ffff:ffff:ffff:ffff:ffff:ffff
2ffaa:1::/32ffaa:1:ffff:ffff:ffff:ffff:ffff:ffff
3ffaa:2::/32ffaa:2:ffff:ffff:ffff:ffff:ffff:ffff
4ffaa:3::/32ffaa:3:ffff:ffff:ffff:ffff:ffff:ffff
5ffaa:4::/32ffaa:4:ffff:ffff:ffff:ffff:ffff:ffff
6ffaa:5::/32ffaa:5:ffff:ffff:ffff:ffff:ffff:ffff
7ffaa:6::/32ffaa:6:ffff:ffff:ffff:ffff:ffff:ffff
8ffaa:7::/32ffaa:7:ffff:ffff:ffff:ffff:ffff:ffff
9ffaa:8::/32ffaa:8:ffff:ffff:ffff:ffff:ffff:ffff
10ffaa:9::/32ffaa:9:ffff:ffff:ffff:ffff:ffff:ffff
11ffaa:a::/32ffaa:a:ffff:ffff:ffff:ffff:ffff:ffff
12ffaa:b::/32ffaa:b:ffff:ffff:ffff:ffff:ffff:ffff
13ffaa:c::/32ffaa:c:ffff:ffff:ffff:ffff:ffff:ffff
14ffaa:d::/32ffaa:d:ffff:ffff:ffff:ffff:ffff:ffff
15ffaa:e::/32ffaa:e:ffff:ffff:ffff:ffff:ffff:ffff
16ffaa:f::/32ffaa:f:ffff:ffff:ffff:ffff:ffff:ffff
17ffaa:10::/32ffaa:10:ffff:ffff:ffff:ffff:ffff:ffff
18ffaa:11::/32ffaa:11:ffff:ffff:ffff:ffff:ffff:ffff
19ffaa:12::/32ffaa:12:ffff:ffff:ffff:ffff:ffff:ffff
20ffaa:13::/32ffaa:13:ffff:ffff:ffff:ffff:ffff:ffff
21ffaa:14::/32ffaa:14:ffff:ffff:ffff:ffff:ffff:ffff
22ffaa:15::/32ffaa:15:ffff:ffff:ffff:ffff:ffff:ffff
23ffaa:16::/32ffaa:16:ffff:ffff:ffff:ffff:ffff:ffff
24ffaa:17::/32ffaa:17:ffff:ffff:ffff:ffff:ffff:ffff
25ffaa:18::/32ffaa:18:ffff:ffff:ffff:ffff:ffff:ffff
26ffaa:19::/32ffaa:19:ffff:ffff:ffff:ffff:ffff:ffff
27ffaa:1a::/32ffaa:1a:ffff:ffff:ffff:ffff:ffff:ffff
28ffaa:1b::/32ffaa:1b:ffff:ffff:ffff:ffff:ffff:ffff
29ffaa:1c::/32ffaa:1c:ffff:ffff:ffff:ffff:ffff:ffff
30ffaa:1d::/32ffaa:1d:ffff:ffff:ffff:ffff:ffff:ffff
31ffaa:1e::/32ffaa:1e:ffff:ffff:ffff:ffff:ffff:ffff
32ffaa:1f::/32ffaa:1f:ffff:ffff:ffff:ffff:ffff:ffff
33ffaa:20::/32ffaa:20:ffff:ffff:ffff:ffff:ffff:ffff
34ffaa:21::/32ffaa:21:ffff:ffff:ffff:ffff:ffff:ffff
35ffaa:22::/32ffaa:22:ffff:ffff:ffff:ffff:ffff:ffff
36ffaa:23::/32ffaa:23:ffff:ffff:ffff:ffff:ffff:ffff
37ffaa:24::/32ffaa:24:ffff:ffff:ffff:ffff:ffff:ffff
38ffaa:25::/32ffaa:25:ffff:ffff:ffff:ffff:ffff:ffff
39ffaa:26::/32ffaa:26:ffff:ffff:ffff:ffff:ffff:ffff
40ffaa:27::/32ffaa:27:ffff:ffff:ffff:ffff:ffff:ffff
41ffaa:28::/32ffaa:28:ffff:ffff:ffff:ffff:ffff:ffff
42ffaa:29::/32ffaa:29:ffff:ffff:ffff:ffff:ffff:ffff
43ffaa:2a::/32ffaa:2a:ffff:ffff:ffff:ffff:ffff:ffff
44ffaa:2b::/32ffaa:2b:ffff:ffff:ffff:ffff:ffff:ffff
45ffaa:2c::/32ffaa:2c:ffff:ffff:ffff:ffff:ffff:ffff
46ffaa:2d::/32ffaa:2d:ffff:ffff:ffff:ffff:ffff:ffff
47ffaa:2e::/32ffaa:2e:ffff:ffff:ffff:ffff:ffff:ffff
48ffaa:2f::/32ffaa:2f:ffff:ffff:ffff:ffff:ffff:ffff
49ffaa:30::/32ffaa:30:ffff:ffff:ffff:ffff:ffff:ffff
50ffaa:31::/32ffaa:31:ffff:ffff:ffff:ffff:ffff:ffff
51ffaa:32::/32ffaa:32:ffff:ffff:ffff:ffff:ffff:ffff
52ffaa:33::/32ffaa:33:ffff:ffff:ffff:ffff:ffff:ffff
53ffaa:34::/32ffaa:34:ffff:ffff:ffff:ffff:ffff:ffff
54ffaa:35::/32ffaa:35:ffff:ffff:ffff:ffff:ffff:ffff
55ffaa:36::/32ffaa:36:ffff:ffff:ffff:ffff:ffff:ffff
56ffaa:37::/32ffaa:37:ffff:ffff:ffff:ffff:ffff:ffff
57ffaa:38::/32ffaa:38:ffff:ffff:ffff:ffff:ffff:ffff
58ffaa:39::/32ffaa:39:ffff:ffff:ffff:ffff:ffff:ffff
59ffaa:3a::/32ffaa:3a:ffff:ffff:ffff:ffff:ffff:ffff
60ffaa:3b::/32ffaa:3b:ffff:ffff:ffff:ffff:ffff:ffff
61ffaa:3c::/32ffaa:3c:ffff:ffff:ffff:ffff:ffff:ffff
62ffaa:3d::/32ffaa:3d:ffff:ffff:ffff:ffff:ffff:ffff
63ffaa:3e::/32ffaa:3e:ffff:ffff:ffff:ffff:ffff:ffff
64ffaa:3f::/32ffaa:3f:ffff:ffff:ffff:ffff:ffff:ffff
65ffaa:40::/32ffaa:40:ffff:ffff:ffff:ffff:ffff:ffff
66ffaa:41::/32ffaa:41:ffff:ffff:ffff:ffff:ffff:ffff
67ffaa:42::/32ffaa:42:ffff:ffff:ffff:ffff:ffff:ffff
68ffaa:43::/32ffaa:43:ffff:ffff:ffff:ffff:ffff:ffff
69ffaa:44::/32ffaa:44:ffff:ffff:ffff:ffff:ffff:ffff
70ffaa:45::/32ffaa:45:ffff:ffff:ffff:ffff:ffff:ffff
71ffaa:46::/32ffaa:46:ffff:ffff:ffff:ffff:ffff:ffff
72ffaa:47::/32ffaa:47:ffff:ffff:ffff:ffff:ffff:ffff
73ffaa:48::/32ffaa:48:ffff:ffff:ffff:ffff:ffff:ffff
74ffaa:49::/32ffaa:49:ffff:ffff:ffff:ffff:ffff:ffff
75ffaa:4a::/32ffaa:4a:ffff:ffff:ffff:ffff:ffff:ffff
76ffaa:4b::/32ffaa:4b:ffff:ffff:ffff:ffff:ffff:ffff
77ffaa:4c::/32ffaa:4c:ffff:ffff:ffff:ffff:ffff:ffff
78ffaa:4d::/32ffaa:4d:ffff:ffff:ffff:ffff:ffff:ffff
79ffaa:4e::/32ffaa:4e:ffff:ffff:ffff:ffff:ffff:ffff
80ffaa:4f::/32ffaa:4f:ffff:ffff:ffff:ffff:ffff:ffff
81ffaa:50::/32ffaa:50:ffff:ffff:ffff:ffff:ffff:ffff
82ffaa:51::/32ffaa:51:ffff:ffff:ffff:ffff:ffff:ffff
83ffaa:52::/32ffaa:52:ffff:ffff:ffff:ffff:ffff:ffff
84ffaa:53::/32ffaa:53:ffff:ffff:ffff:ffff:ffff:ffff
85ffaa:54::/32ffaa:54:ffff:ffff:ffff:ffff:ffff:ffff
86ffaa:55::/32ffaa:55:ffff:ffff:ffff:ffff:ffff:ffff
87ffaa:56::/32ffaa:56:ffff:ffff:ffff:ffff:ffff:ffff
88ffaa:57::/32ffaa:57:ffff:ffff:ffff:ffff:ffff:ffff
89ffaa:58::/32ffaa:58:ffff:ffff:ffff:ffff:ffff:ffff
90ffaa:59::/32ffaa:59:ffff:ffff:ffff:ffff:ffff:ffff
91ffaa:5a::/32ffaa:5a:ffff:ffff:ffff:ffff:ffff:ffff
92ffaa:5b::/32ffaa:5b:ffff:ffff:ffff:ffff:ffff:ffff
93ffaa:5c::/32ffaa:5c:ffff:ffff:ffff:ffff:ffff:ffff
94ffaa:5d::/32ffaa:5d:ffff:ffff:ffff:ffff:ffff:ffff
95ffaa:5e::/32ffaa:5e:ffff:ffff:ffff:ffff:ffff:ffff
96ffaa:5f::/32ffaa:5f:ffff:ffff:ffff:ffff:ffff:ffff
97ffaa:60::/32ffaa:60:ffff:ffff:ffff:ffff:ffff:ffff
98ffaa:61::/32ffaa:61:ffff:ffff:ffff:ffff:ffff:ffff
99ffaa:62::/32ffaa:62:ffff:ffff:ffff:ffff:ffff:ffff
100ffaa:63::/32ffaa:63:ffff:ffff:ffff:ffff:ffff:ffff
101ffaa:64::/32ffaa:64:ffff:ffff:ffff:ffff:ffff:ffff
102ffaa:65::/32ffaa:65:ffff:ffff:ffff:ffff:ffff:ffff
103ffaa:66::/32ffaa:66:ffff:ffff:ffff:ffff:ffff:ffff
104ffaa:67::/32ffaa:67:ffff:ffff:ffff:ffff:ffff:ffff
105ffaa:68::/32ffaa:68:ffff:ffff:ffff:ffff:ffff:ffff
106ffaa:69::/32ffaa:69:ffff:ffff:ffff:ffff:ffff:ffff
107ffaa:6a::/32ffaa:6a:ffff:ffff:ffff:ffff:ffff:ffff
108ffaa:6b::/32ffaa:6b:ffff:ffff:ffff:ffff:ffff:ffff
109ffaa:6c::/32ffaa:6c:ffff:ffff:ffff:ffff:ffff:ffff
110ffaa:6d::/32ffaa:6d:ffff:ffff:ffff:ffff:ffff:ffff
111ffaa:6e::/32ffaa:6e:ffff:ffff:ffff:ffff:ffff:ffff
112ffaa:6f::/32ffaa:6f:ffff:ffff:ffff:ffff:ffff:ffff
113ffaa:70::/32ffaa:70:ffff:ffff:ffff:ffff:ffff:ffff
114ffaa:71::/32ffaa:71:ffff:ffff:ffff:ffff:ffff:ffff
115ffaa:72::/32ffaa:72:ffff:ffff:ffff:ffff:ffff:ffff
116ffaa:73::/32ffaa:73:ffff:ffff:ffff:ffff:ffff:ffff
117ffaa:74::/32ffaa:74:ffff:ffff:ffff:ffff:ffff:ffff
118ffaa:75::/32ffaa:75:ffff:ffff:ffff:ffff:ffff:ffff
119ffaa:76::/32ffaa:76:ffff:ffff:ffff:ffff:ffff:ffff
120ffaa:77::/32ffaa:77:ffff:ffff:ffff:ffff:ffff:ffff
121ffaa:78::/32ffaa:78:ffff:ffff:ffff:ffff:ffff:ffff
122ffaa:79::/32ffaa:79:ffff:ffff:ffff:ffff:ffff:ffff
123ffaa:7a::/32ffaa:7a:ffff:ffff:ffff:ffff:ffff:ffff
124ffaa:7b::/32ffaa:7b:ffff:ffff:ffff:ffff:ffff:ffff
125ffaa:7c::/32ffaa:7c:ffff:ffff:ffff:ffff:ffff:ffff
126ffaa:7d::/32ffaa:7d:ffff:ffff:ffff:ffff:ffff:ffff
127ffaa:7e::/32ffaa:7e:ffff:ffff:ffff:ffff:ffff:ffff
128ffaa:7f::/32ffaa:7f:ffff:ffff:ffff:ffff:ffff:ffff
129ffaa:80::/32ffaa:80:ffff:ffff:ffff:ffff:ffff:ffff
130ffaa:81::/32ffaa:81:ffff:ffff:ffff:ffff:ffff:ffff
131ffaa:82::/32ffaa:82:ffff:ffff:ffff:ffff:ffff:ffff
132ffaa:83::/32ffaa:83:ffff:ffff:ffff:ffff:ffff:ffff
133ffaa:84::/32ffaa:84:ffff:ffff:ffff:ffff:ffff:ffff
134ffaa:85::/32ffaa:85:ffff:ffff:ffff:ffff:ffff:ffff
135ffaa:86::/32ffaa:86:ffff:ffff:ffff:ffff:ffff:ffff
136ffaa:87::/32ffaa:87:ffff:ffff:ffff:ffff:ffff:ffff
137ffaa:88::/32ffaa:88:ffff:ffff:ffff:ffff:ffff:ffff
138ffaa:89::/32ffaa:89:ffff:ffff:ffff:ffff:ffff:ffff
139ffaa:8a::/32ffaa:8a:ffff:ffff:ffff:ffff:ffff:ffff
140ffaa:8b::/32ffaa:8b:ffff:ffff:ffff:ffff:ffff:ffff
141ffaa:8c::/32ffaa:8c:ffff:ffff:ffff:ffff:ffff:ffff
142ffaa:8d::/32ffaa:8d:ffff:ffff:ffff:ffff:ffff:ffff
143ffaa:8e::/32ffaa:8e:ffff:ffff:ffff:ffff:ffff:ffff
144ffaa:8f::/32ffaa:8f:ffff:ffff:ffff:ffff:ffff:ffff
145ffaa:90::/32ffaa:90:ffff:ffff:ffff:ffff:ffff:ffff
146ffaa:91::/32ffaa:91:ffff:ffff:ffff:ffff:ffff:ffff
147ffaa:92::/32ffaa:92:ffff:ffff:ffff:ffff:ffff:ffff
148ffaa:93::/32ffaa:93:ffff:ffff:ffff:ffff:ffff:ffff
149ffaa:94::/32ffaa:94:ffff:ffff:ffff:ffff:ffff:ffff
150ffaa:95::/32ffaa:95:ffff:ffff:ffff:ffff:ffff:ffff
151ffaa:96::/32ffaa:96:ffff:ffff:ffff:ffff:ffff:ffff
152ffaa:97::/32ffaa:97:ffff:ffff:ffff:ffff:ffff:ffff
153ffaa:98::/32ffaa:98:ffff:ffff:ffff:ffff:ffff:ffff
154ffaa:99::/32ffaa:99:ffff:ffff:ffff:ffff:ffff:ffff
155ffaa:9a::/32ffaa:9a:ffff:ffff:ffff:ffff:ffff:ffff
156ffaa:9b::/32ffaa:9b:ffff:ffff:ffff:ffff:ffff:ffff
157ffaa:9c::/32ffaa:9c:ffff:ffff:ffff:ffff:ffff:ffff
158ffaa:9d::/32ffaa:9d:ffff:ffff:ffff:ffff:ffff:ffff
159ffaa:9e::/32ffaa:9e:ffff:ffff:ffff:ffff:ffff:ffff
160ffaa:9f::/32ffaa:9f:ffff:ffff:ffff:ffff:ffff:ffff
161ffaa:a0::/32ffaa:a0:ffff:ffff:ffff:ffff:ffff:ffff
162ffaa:a1::/32ffaa:a1:ffff:ffff:ffff:ffff:ffff:ffff
163ffaa:a2::/32ffaa:a2:ffff:ffff:ffff:ffff:ffff:ffff
164ffaa:a3::/32ffaa:a3:ffff:ffff:ffff:ffff:ffff:ffff
165ffaa:a4::/32ffaa:a4:ffff:ffff:ffff:ffff:ffff:ffff
166ffaa:a5::/32ffaa:a5:ffff:ffff:ffff:ffff:ffff:ffff
167ffaa:a6::/32ffaa:a6:ffff:ffff:ffff:ffff:ffff:ffff
168ffaa:a7::/32ffaa:a7:ffff:ffff:ffff:ffff:ffff:ffff
169ffaa:a8::/32ffaa:a8:ffff:ffff:ffff:ffff:ffff:ffff
170ffaa:a9::/32ffaa:a9:ffff:ffff:ffff:ffff:ffff:ffff
171ffaa:aa::/32ffaa:aa:ffff:ffff:ffff:ffff:ffff:ffff
172ffaa:ab::/32ffaa:ab:ffff:ffff:ffff:ffff:ffff:ffff
173ffaa:ac::/32ffaa:ac:ffff:ffff:ffff:ffff:ffff:ffff
174ffaa:ad::/32ffaa:ad:ffff:ffff:ffff:ffff:ffff:ffff
175ffaa:ae::/32ffaa:ae:ffff:ffff:ffff:ffff:ffff:ffff
176ffaa:af::/32ffaa:af:ffff:ffff:ffff:ffff:ffff:ffff
177ffaa:b0::/32ffaa:b0:ffff:ffff:ffff:ffff:ffff:ffff
178ffaa:b1::/32ffaa:b1:ffff:ffff:ffff:ffff:ffff:ffff
179ffaa:b2::/32ffaa:b2:ffff:ffff:ffff:ffff:ffff:ffff
180ffaa:b3::/32ffaa:b3:ffff:ffff:ffff:ffff:ffff:ffff
181ffaa:b4::/32ffaa:b4:ffff:ffff:ffff:ffff:ffff:ffff
182ffaa:b5::/32ffaa:b5:ffff:ffff:ffff:ffff:ffff:ffff
183ffaa:b6::/32ffaa:b6:ffff:ffff:ffff:ffff:ffff:ffff
184ffaa:b7::/32ffaa:b7:ffff:ffff:ffff:ffff:ffff:ffff
185ffaa:b8::/32ffaa:b8:ffff:ffff:ffff:ffff:ffff:ffff
186ffaa:b9::/32ffaa:b9:ffff:ffff:ffff:ffff:ffff:ffff
187ffaa:ba::/32ffaa:ba:ffff:ffff:ffff:ffff:ffff:ffff
188ffaa:bb::/32ffaa:bb:ffff:ffff:ffff:ffff:ffff:ffff
189ffaa:bc::/32ffaa:bc:ffff:ffff:ffff:ffff:ffff:ffff
190ffaa:bd::/32ffaa:bd:ffff:ffff:ffff:ffff:ffff:ffff
191ffaa:be::/32ffaa:be:ffff:ffff:ffff:ffff:ffff:ffff
192ffaa:bf::/32ffaa:bf:ffff:ffff:ffff:ffff:ffff:ffff
193ffaa:c0::/32ffaa:c0:ffff:ffff:ffff:ffff:ffff:ffff
194ffaa:c1::/32ffaa:c1:ffff:ffff:ffff:ffff:ffff:ffff
195ffaa:c2::/32ffaa:c2:ffff:ffff:ffff:ffff:ffff:ffff
196ffaa:c3::/32ffaa:c3:ffff:ffff:ffff:ffff:ffff:ffff
197ffaa:c4::/32ffaa:c4:ffff:ffff:ffff:ffff:ffff:ffff
198ffaa:c5::/32ffaa:c5:ffff:ffff:ffff:ffff:ffff:ffff
199ffaa:c6::/32ffaa:c6:ffff:ffff:ffff:ffff:ffff:ffff
200ffaa:c7::/32ffaa:c7:ffff:ffff:ffff:ffff:ffff:ffff
201ffaa:c8::/32ffaa:c8:ffff:ffff:ffff:ffff:ffff:ffff
202ffaa:c9::/32ffaa:c9:ffff:ffff:ffff:ffff:ffff:ffff
203ffaa:ca::/32ffaa:ca:ffff:ffff:ffff:ffff:ffff:ffff
204ffaa:cb::/32ffaa:cb:ffff:ffff:ffff:ffff:ffff:ffff
205ffaa:cc::/32ffaa:cc:ffff:ffff:ffff:ffff:ffff:ffff
206ffaa:cd::/32ffaa:cd:ffff:ffff:ffff:ffff:ffff:ffff
207ffaa:ce::/32ffaa:ce:ffff:ffff:ffff:ffff:ffff:ffff
208ffaa:cf::/32ffaa:cf:ffff:ffff:ffff:ffff:ffff:ffff
209ffaa:d0::/32ffaa:d0:ffff:ffff:ffff:ffff:ffff:ffff
210ffaa:d1::/32ffaa:d1:ffff:ffff:ffff:ffff:ffff:ffff
211ffaa:d2::/32ffaa:d2:ffff:ffff:ffff:ffff:ffff:ffff
212ffaa:d3::/32ffaa:d3:ffff:ffff:ffff:ffff:ffff:ffff
213ffaa:d4::/32ffaa:d4:ffff:ffff:ffff:ffff:ffff:ffff
214ffaa:d5::/32ffaa:d5:ffff:ffff:ffff:ffff:ffff:ffff
215ffaa:d6::/32ffaa:d6:ffff:ffff:ffff:ffff:ffff:ffff
216ffaa:d7::/32ffaa:d7:ffff:ffff:ffff:ffff:ffff:ffff
217ffaa:d8::/32ffaa:d8:ffff:ffff:ffff:ffff:ffff:ffff
218ffaa:d9::/32ffaa:d9:ffff:ffff:ffff:ffff:ffff:ffff
219ffaa:da::/32ffaa:da:ffff:ffff:ffff:ffff:ffff:ffff
220ffaa:db::/32ffaa:db:ffff:ffff:ffff:ffff:ffff:ffff
221ffaa:dc::/32ffaa:dc:ffff:ffff:ffff:ffff:ffff:ffff
222ffaa:dd::/32ffaa:dd:ffff:ffff:ffff:ffff:ffff:ffff
223ffaa:de::/32ffaa:de:ffff:ffff:ffff:ffff:ffff:ffff
224ffaa:df::/32ffaa:df:ffff:ffff:ffff:ffff:ffff:ffff
225ffaa:e0::/32ffaa:e0:ffff:ffff:ffff:ffff:ffff:ffff
226ffaa:e1::/32ffaa:e1:ffff:ffff:ffff:ffff:ffff:ffff
227ffaa:e2::/32ffaa:e2:ffff:ffff:ffff:ffff:ffff:ffff
228ffaa:e3::/32ffaa:e3:ffff:ffff:ffff:ffff:ffff:ffff
229ffaa:e4::/32ffaa:e4:ffff:ffff:ffff:ffff:ffff:ffff
230ffaa:e5::/32ffaa:e5:ffff:ffff:ffff:ffff:ffff:ffff
231ffaa:e6::/32ffaa:e6:ffff:ffff:ffff:ffff:ffff:ffff
232ffaa:e7::/32ffaa:e7:ffff:ffff:ffff:ffff:ffff:ffff
233ffaa:e8::/32ffaa:e8:ffff:ffff:ffff:ffff:ffff:ffff
234ffaa:e9::/32ffaa:e9:ffff:ffff:ffff:ffff:ffff:ffff
235ffaa:ea::/32ffaa:ea:ffff:ffff:ffff:ffff:ffff:ffff
236ffaa:eb::/32ffaa:eb:ffff:ffff:ffff:ffff:ffff:ffff
237ffaa:ec::/32ffaa:ec:ffff:ffff:ffff:ffff:ffff:ffff
238ffaa:ed::/32ffaa:ed:ffff:ffff:ffff:ffff:ffff:ffff
239ffaa:ee::/32ffaa:ee:ffff:ffff:ffff:ffff:ffff:ffff
240ffaa:ef::/32ffaa:ef:ffff:ffff:ffff:ffff:ffff:ffff
241ffaa:f0::/32ffaa:f0:ffff:ffff:ffff:ffff:ffff:ffff
242ffaa:f1::/32ffaa:f1:ffff:ffff:ffff:ffff:ffff:ffff
243ffaa:f2::/32ffaa:f2:ffff:ffff:ffff:ffff:ffff:ffff
244ffaa:f3::/32ffaa:f3:ffff:ffff:ffff:ffff:ffff:ffff
245ffaa:f4::/32ffaa:f4:ffff:ffff:ffff:ffff:ffff:ffff
246ffaa:f5::/32ffaa:f5:ffff:ffff:ffff:ffff:ffff:ffff
247ffaa:f6::/32ffaa:f6:ffff:ffff:ffff:ffff:ffff:ffff
248ffaa:f7::/32ffaa:f7:ffff:ffff:ffff:ffff:ffff:ffff
249ffaa:f8::/32ffaa:f8:ffff:ffff:ffff:ffff:ffff:ffff
250ffaa:f9::/32ffaa:f9:ffff:ffff:ffff:ffff:ffff:ffff
251ffaa:fa::/32ffaa:fa:ffff:ffff:ffff:ffff:ffff:ffff
252ffaa:fb::/32ffaa:fb:ffff:ffff:ffff:ffff:ffff:ffff
253ffaa:fc::/32ffaa:fc:ffff:ffff:ffff:ffff:ffff:ffff
254ffaa:fd::/32ffaa:fd:ffff:ffff:ffff:ffff:ffff:ffff
255ffaa:fe::/32ffaa:fe:ffff:ffff:ffff:ffff:ffff:ffff
256ffaa:ff::/32ffaa:ff:ffff:ffff:ffff:ffff:ffff:ffff

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.