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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
ffcc::/16
First address
ffcc::
Last address
ffcc: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
ffcc:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
c.c.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)

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

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