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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
ff95::/16
First address
ff95::
Last address
ff95: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
ff95:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
5.9.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)

ff95::/16 makes 65,536 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
1ff95::/32ff95:0:ffff:ffff:ffff:ffff:ffff:ffff
2ff95:1::/32ff95:1:ffff:ffff:ffff:ffff:ffff:ffff
3ff95:2::/32ff95:2:ffff:ffff:ffff:ffff:ffff:ffff
4ff95:3::/32ff95:3:ffff:ffff:ffff:ffff:ffff:ffff
5ff95:4::/32ff95:4:ffff:ffff:ffff:ffff:ffff:ffff
6ff95:5::/32ff95:5:ffff:ffff:ffff:ffff:ffff:ffff
7ff95:6::/32ff95:6:ffff:ffff:ffff:ffff:ffff:ffff
8ff95:7::/32ff95:7:ffff:ffff:ffff:ffff:ffff:ffff
9ff95:8::/32ff95:8:ffff:ffff:ffff:ffff:ffff:ffff
10ff95:9::/32ff95:9:ffff:ffff:ffff:ffff:ffff:ffff
11ff95:a::/32ff95:a:ffff:ffff:ffff:ffff:ffff:ffff
12ff95:b::/32ff95:b:ffff:ffff:ffff:ffff:ffff:ffff
13ff95:c::/32ff95:c:ffff:ffff:ffff:ffff:ffff:ffff
14ff95:d::/32ff95:d:ffff:ffff:ffff:ffff:ffff:ffff
15ff95:e::/32ff95:e:ffff:ffff:ffff:ffff:ffff:ffff
16ff95:f::/32ff95:f:ffff:ffff:ffff:ffff:ffff:ffff
17ff95:10::/32ff95:10:ffff:ffff:ffff:ffff:ffff:ffff
18ff95:11::/32ff95:11:ffff:ffff:ffff:ffff:ffff:ffff
19ff95:12::/32ff95:12:ffff:ffff:ffff:ffff:ffff:ffff
20ff95:13::/32ff95:13:ffff:ffff:ffff:ffff:ffff:ffff
21ff95:14::/32ff95:14:ffff:ffff:ffff:ffff:ffff:ffff
22ff95:15::/32ff95:15:ffff:ffff:ffff:ffff:ffff:ffff
23ff95:16::/32ff95:16:ffff:ffff:ffff:ffff:ffff:ffff
24ff95:17::/32ff95:17:ffff:ffff:ffff:ffff:ffff:ffff
25ff95:18::/32ff95:18:ffff:ffff:ffff:ffff:ffff:ffff
26ff95:19::/32ff95:19:ffff:ffff:ffff:ffff:ffff:ffff
27ff95:1a::/32ff95:1a:ffff:ffff:ffff:ffff:ffff:ffff
28ff95:1b::/32ff95:1b:ffff:ffff:ffff:ffff:ffff:ffff
29ff95:1c::/32ff95:1c:ffff:ffff:ffff:ffff:ffff:ffff
30ff95:1d::/32ff95:1d:ffff:ffff:ffff:ffff:ffff:ffff
31ff95:1e::/32ff95:1e:ffff:ffff:ffff:ffff:ffff:ffff
32ff95:1f::/32ff95:1f:ffff:ffff:ffff:ffff:ffff:ffff
33ff95:20::/32ff95:20:ffff:ffff:ffff:ffff:ffff:ffff
34ff95:21::/32ff95:21:ffff:ffff:ffff:ffff:ffff:ffff
35ff95:22::/32ff95:22:ffff:ffff:ffff:ffff:ffff:ffff
36ff95:23::/32ff95:23:ffff:ffff:ffff:ffff:ffff:ffff
37ff95:24::/32ff95:24:ffff:ffff:ffff:ffff:ffff:ffff
38ff95:25::/32ff95:25:ffff:ffff:ffff:ffff:ffff:ffff
39ff95:26::/32ff95:26:ffff:ffff:ffff:ffff:ffff:ffff
40ff95:27::/32ff95:27:ffff:ffff:ffff:ffff:ffff:ffff
41ff95:28::/32ff95:28:ffff:ffff:ffff:ffff:ffff:ffff
42ff95:29::/32ff95:29:ffff:ffff:ffff:ffff:ffff:ffff
43ff95:2a::/32ff95:2a:ffff:ffff:ffff:ffff:ffff:ffff
44ff95:2b::/32ff95:2b:ffff:ffff:ffff:ffff:ffff:ffff
45ff95:2c::/32ff95:2c:ffff:ffff:ffff:ffff:ffff:ffff
46ff95:2d::/32ff95:2d:ffff:ffff:ffff:ffff:ffff:ffff
47ff95:2e::/32ff95:2e:ffff:ffff:ffff:ffff:ffff:ffff
48ff95:2f::/32ff95:2f:ffff:ffff:ffff:ffff:ffff:ffff
49ff95:30::/32ff95:30:ffff:ffff:ffff:ffff:ffff:ffff
50ff95:31::/32ff95:31:ffff:ffff:ffff:ffff:ffff:ffff
51ff95:32::/32ff95:32:ffff:ffff:ffff:ffff:ffff:ffff
52ff95:33::/32ff95:33:ffff:ffff:ffff:ffff:ffff:ffff
53ff95:34::/32ff95:34:ffff:ffff:ffff:ffff:ffff:ffff
54ff95:35::/32ff95:35:ffff:ffff:ffff:ffff:ffff:ffff
55ff95:36::/32ff95:36:ffff:ffff:ffff:ffff:ffff:ffff
56ff95:37::/32ff95:37:ffff:ffff:ffff:ffff:ffff:ffff
57ff95:38::/32ff95:38:ffff:ffff:ffff:ffff:ffff:ffff
58ff95:39::/32ff95:39:ffff:ffff:ffff:ffff:ffff:ffff
59ff95:3a::/32ff95:3a:ffff:ffff:ffff:ffff:ffff:ffff
60ff95:3b::/32ff95:3b:ffff:ffff:ffff:ffff:ffff:ffff
61ff95:3c::/32ff95:3c:ffff:ffff:ffff:ffff:ffff:ffff
62ff95:3d::/32ff95:3d:ffff:ffff:ffff:ffff:ffff:ffff
63ff95:3e::/32ff95:3e:ffff:ffff:ffff:ffff:ffff:ffff
64ff95:3f::/32ff95:3f:ffff:ffff:ffff:ffff:ffff:ffff
65ff95:40::/32ff95:40:ffff:ffff:ffff:ffff:ffff:ffff
66ff95:41::/32ff95:41:ffff:ffff:ffff:ffff:ffff:ffff
67ff95:42::/32ff95:42:ffff:ffff:ffff:ffff:ffff:ffff
68ff95:43::/32ff95:43:ffff:ffff:ffff:ffff:ffff:ffff
69ff95:44::/32ff95:44:ffff:ffff:ffff:ffff:ffff:ffff
70ff95:45::/32ff95:45:ffff:ffff:ffff:ffff:ffff:ffff
71ff95:46::/32ff95:46:ffff:ffff:ffff:ffff:ffff:ffff
72ff95:47::/32ff95:47:ffff:ffff:ffff:ffff:ffff:ffff
73ff95:48::/32ff95:48:ffff:ffff:ffff:ffff:ffff:ffff
74ff95:49::/32ff95:49:ffff:ffff:ffff:ffff:ffff:ffff
75ff95:4a::/32ff95:4a:ffff:ffff:ffff:ffff:ffff:ffff
76ff95:4b::/32ff95:4b:ffff:ffff:ffff:ffff:ffff:ffff
77ff95:4c::/32ff95:4c:ffff:ffff:ffff:ffff:ffff:ffff
78ff95:4d::/32ff95:4d:ffff:ffff:ffff:ffff:ffff:ffff
79ff95:4e::/32ff95:4e:ffff:ffff:ffff:ffff:ffff:ffff
80ff95:4f::/32ff95:4f:ffff:ffff:ffff:ffff:ffff:ffff
81ff95:50::/32ff95:50:ffff:ffff:ffff:ffff:ffff:ffff
82ff95:51::/32ff95:51:ffff:ffff:ffff:ffff:ffff:ffff
83ff95:52::/32ff95:52:ffff:ffff:ffff:ffff:ffff:ffff
84ff95:53::/32ff95:53:ffff:ffff:ffff:ffff:ffff:ffff
85ff95:54::/32ff95:54:ffff:ffff:ffff:ffff:ffff:ffff
86ff95:55::/32ff95:55:ffff:ffff:ffff:ffff:ffff:ffff
87ff95:56::/32ff95:56:ffff:ffff:ffff:ffff:ffff:ffff
88ff95:57::/32ff95:57:ffff:ffff:ffff:ffff:ffff:ffff
89ff95:58::/32ff95:58:ffff:ffff:ffff:ffff:ffff:ffff
90ff95:59::/32ff95:59:ffff:ffff:ffff:ffff:ffff:ffff
91ff95:5a::/32ff95:5a:ffff:ffff:ffff:ffff:ffff:ffff
92ff95:5b::/32ff95:5b:ffff:ffff:ffff:ffff:ffff:ffff
93ff95:5c::/32ff95:5c:ffff:ffff:ffff:ffff:ffff:ffff
94ff95:5d::/32ff95:5d:ffff:ffff:ffff:ffff:ffff:ffff
95ff95:5e::/32ff95:5e:ffff:ffff:ffff:ffff:ffff:ffff
96ff95:5f::/32ff95:5f:ffff:ffff:ffff:ffff:ffff:ffff
97ff95:60::/32ff95:60:ffff:ffff:ffff:ffff:ffff:ffff
98ff95:61::/32ff95:61:ffff:ffff:ffff:ffff:ffff:ffff
99ff95:62::/32ff95:62:ffff:ffff:ffff:ffff:ffff:ffff
100ff95:63::/32ff95:63:ffff:ffff:ffff:ffff:ffff:ffff
101ff95:64::/32ff95:64:ffff:ffff:ffff:ffff:ffff:ffff
102ff95:65::/32ff95:65:ffff:ffff:ffff:ffff:ffff:ffff
103ff95:66::/32ff95:66:ffff:ffff:ffff:ffff:ffff:ffff
104ff95:67::/32ff95:67:ffff:ffff:ffff:ffff:ffff:ffff
105ff95:68::/32ff95:68:ffff:ffff:ffff:ffff:ffff:ffff
106ff95:69::/32ff95:69:ffff:ffff:ffff:ffff:ffff:ffff
107ff95:6a::/32ff95:6a:ffff:ffff:ffff:ffff:ffff:ffff
108ff95:6b::/32ff95:6b:ffff:ffff:ffff:ffff:ffff:ffff
109ff95:6c::/32ff95:6c:ffff:ffff:ffff:ffff:ffff:ffff
110ff95:6d::/32ff95:6d:ffff:ffff:ffff:ffff:ffff:ffff
111ff95:6e::/32ff95:6e:ffff:ffff:ffff:ffff:ffff:ffff
112ff95:6f::/32ff95:6f:ffff:ffff:ffff:ffff:ffff:ffff
113ff95:70::/32ff95:70:ffff:ffff:ffff:ffff:ffff:ffff
114ff95:71::/32ff95:71:ffff:ffff:ffff:ffff:ffff:ffff
115ff95:72::/32ff95:72:ffff:ffff:ffff:ffff:ffff:ffff
116ff95:73::/32ff95:73:ffff:ffff:ffff:ffff:ffff:ffff
117ff95:74::/32ff95:74:ffff:ffff:ffff:ffff:ffff:ffff
118ff95:75::/32ff95:75:ffff:ffff:ffff:ffff:ffff:ffff
119ff95:76::/32ff95:76:ffff:ffff:ffff:ffff:ffff:ffff
120ff95:77::/32ff95:77:ffff:ffff:ffff:ffff:ffff:ffff
121ff95:78::/32ff95:78:ffff:ffff:ffff:ffff:ffff:ffff
122ff95:79::/32ff95:79:ffff:ffff:ffff:ffff:ffff:ffff
123ff95:7a::/32ff95:7a:ffff:ffff:ffff:ffff:ffff:ffff
124ff95:7b::/32ff95:7b:ffff:ffff:ffff:ffff:ffff:ffff
125ff95:7c::/32ff95:7c:ffff:ffff:ffff:ffff:ffff:ffff
126ff95:7d::/32ff95:7d:ffff:ffff:ffff:ffff:ffff:ffff
127ff95:7e::/32ff95:7e:ffff:ffff:ffff:ffff:ffff:ffff
128ff95:7f::/32ff95:7f:ffff:ffff:ffff:ffff:ffff:ffff
129ff95:80::/32ff95:80:ffff:ffff:ffff:ffff:ffff:ffff
130ff95:81::/32ff95:81:ffff:ffff:ffff:ffff:ffff:ffff
131ff95:82::/32ff95:82:ffff:ffff:ffff:ffff:ffff:ffff
132ff95:83::/32ff95:83:ffff:ffff:ffff:ffff:ffff:ffff
133ff95:84::/32ff95:84:ffff:ffff:ffff:ffff:ffff:ffff
134ff95:85::/32ff95:85:ffff:ffff:ffff:ffff:ffff:ffff
135ff95:86::/32ff95:86:ffff:ffff:ffff:ffff:ffff:ffff
136ff95:87::/32ff95:87:ffff:ffff:ffff:ffff:ffff:ffff
137ff95:88::/32ff95:88:ffff:ffff:ffff:ffff:ffff:ffff
138ff95:89::/32ff95:89:ffff:ffff:ffff:ffff:ffff:ffff
139ff95:8a::/32ff95:8a:ffff:ffff:ffff:ffff:ffff:ffff
140ff95:8b::/32ff95:8b:ffff:ffff:ffff:ffff:ffff:ffff
141ff95:8c::/32ff95:8c:ffff:ffff:ffff:ffff:ffff:ffff
142ff95:8d::/32ff95:8d:ffff:ffff:ffff:ffff:ffff:ffff
143ff95:8e::/32ff95:8e:ffff:ffff:ffff:ffff:ffff:ffff
144ff95:8f::/32ff95:8f:ffff:ffff:ffff:ffff:ffff:ffff
145ff95:90::/32ff95:90:ffff:ffff:ffff:ffff:ffff:ffff
146ff95:91::/32ff95:91:ffff:ffff:ffff:ffff:ffff:ffff
147ff95:92::/32ff95:92:ffff:ffff:ffff:ffff:ffff:ffff
148ff95:93::/32ff95:93:ffff:ffff:ffff:ffff:ffff:ffff
149ff95:94::/32ff95:94:ffff:ffff:ffff:ffff:ffff:ffff
150ff95:95::/32ff95:95:ffff:ffff:ffff:ffff:ffff:ffff
151ff95:96::/32ff95:96:ffff:ffff:ffff:ffff:ffff:ffff
152ff95:97::/32ff95:97:ffff:ffff:ffff:ffff:ffff:ffff
153ff95:98::/32ff95:98:ffff:ffff:ffff:ffff:ffff:ffff
154ff95:99::/32ff95:99:ffff:ffff:ffff:ffff:ffff:ffff
155ff95:9a::/32ff95:9a:ffff:ffff:ffff:ffff:ffff:ffff
156ff95:9b::/32ff95:9b:ffff:ffff:ffff:ffff:ffff:ffff
157ff95:9c::/32ff95:9c:ffff:ffff:ffff:ffff:ffff:ffff
158ff95:9d::/32ff95:9d:ffff:ffff:ffff:ffff:ffff:ffff
159ff95:9e::/32ff95:9e:ffff:ffff:ffff:ffff:ffff:ffff
160ff95:9f::/32ff95:9f:ffff:ffff:ffff:ffff:ffff:ffff
161ff95:a0::/32ff95:a0:ffff:ffff:ffff:ffff:ffff:ffff
162ff95:a1::/32ff95:a1:ffff:ffff:ffff:ffff:ffff:ffff
163ff95:a2::/32ff95:a2:ffff:ffff:ffff:ffff:ffff:ffff
164ff95:a3::/32ff95:a3:ffff:ffff:ffff:ffff:ffff:ffff
165ff95:a4::/32ff95:a4:ffff:ffff:ffff:ffff:ffff:ffff
166ff95:a5::/32ff95:a5:ffff:ffff:ffff:ffff:ffff:ffff
167ff95:a6::/32ff95:a6:ffff:ffff:ffff:ffff:ffff:ffff
168ff95:a7::/32ff95:a7:ffff:ffff:ffff:ffff:ffff:ffff
169ff95:a8::/32ff95:a8:ffff:ffff:ffff:ffff:ffff:ffff
170ff95:a9::/32ff95:a9:ffff:ffff:ffff:ffff:ffff:ffff
171ff95:aa::/32ff95:aa:ffff:ffff:ffff:ffff:ffff:ffff
172ff95:ab::/32ff95:ab:ffff:ffff:ffff:ffff:ffff:ffff
173ff95:ac::/32ff95:ac:ffff:ffff:ffff:ffff:ffff:ffff
174ff95:ad::/32ff95:ad:ffff:ffff:ffff:ffff:ffff:ffff
175ff95:ae::/32ff95:ae:ffff:ffff:ffff:ffff:ffff:ffff
176ff95:af::/32ff95:af:ffff:ffff:ffff:ffff:ffff:ffff
177ff95:b0::/32ff95:b0:ffff:ffff:ffff:ffff:ffff:ffff
178ff95:b1::/32ff95:b1:ffff:ffff:ffff:ffff:ffff:ffff
179ff95:b2::/32ff95:b2:ffff:ffff:ffff:ffff:ffff:ffff
180ff95:b3::/32ff95:b3:ffff:ffff:ffff:ffff:ffff:ffff
181ff95:b4::/32ff95:b4:ffff:ffff:ffff:ffff:ffff:ffff
182ff95:b5::/32ff95:b5:ffff:ffff:ffff:ffff:ffff:ffff
183ff95:b6::/32ff95:b6:ffff:ffff:ffff:ffff:ffff:ffff
184ff95:b7::/32ff95:b7:ffff:ffff:ffff:ffff:ffff:ffff
185ff95:b8::/32ff95:b8:ffff:ffff:ffff:ffff:ffff:ffff
186ff95:b9::/32ff95:b9:ffff:ffff:ffff:ffff:ffff:ffff
187ff95:ba::/32ff95:ba:ffff:ffff:ffff:ffff:ffff:ffff
188ff95:bb::/32ff95:bb:ffff:ffff:ffff:ffff:ffff:ffff
189ff95:bc::/32ff95:bc:ffff:ffff:ffff:ffff:ffff:ffff
190ff95:bd::/32ff95:bd:ffff:ffff:ffff:ffff:ffff:ffff
191ff95:be::/32ff95:be:ffff:ffff:ffff:ffff:ffff:ffff
192ff95:bf::/32ff95:bf:ffff:ffff:ffff:ffff:ffff:ffff
193ff95:c0::/32ff95:c0:ffff:ffff:ffff:ffff:ffff:ffff
194ff95:c1::/32ff95:c1:ffff:ffff:ffff:ffff:ffff:ffff
195ff95:c2::/32ff95:c2:ffff:ffff:ffff:ffff:ffff:ffff
196ff95:c3::/32ff95:c3:ffff:ffff:ffff:ffff:ffff:ffff
197ff95:c4::/32ff95:c4:ffff:ffff:ffff:ffff:ffff:ffff
198ff95:c5::/32ff95:c5:ffff:ffff:ffff:ffff:ffff:ffff
199ff95:c6::/32ff95:c6:ffff:ffff:ffff:ffff:ffff:ffff
200ff95:c7::/32ff95:c7:ffff:ffff:ffff:ffff:ffff:ffff
201ff95:c8::/32ff95:c8:ffff:ffff:ffff:ffff:ffff:ffff
202ff95:c9::/32ff95:c9:ffff:ffff:ffff:ffff:ffff:ffff
203ff95:ca::/32ff95:ca:ffff:ffff:ffff:ffff:ffff:ffff
204ff95:cb::/32ff95:cb:ffff:ffff:ffff:ffff:ffff:ffff
205ff95:cc::/32ff95:cc:ffff:ffff:ffff:ffff:ffff:ffff
206ff95:cd::/32ff95:cd:ffff:ffff:ffff:ffff:ffff:ffff
207ff95:ce::/32ff95:ce:ffff:ffff:ffff:ffff:ffff:ffff
208ff95:cf::/32ff95:cf:ffff:ffff:ffff:ffff:ffff:ffff
209ff95:d0::/32ff95:d0:ffff:ffff:ffff:ffff:ffff:ffff
210ff95:d1::/32ff95:d1:ffff:ffff:ffff:ffff:ffff:ffff
211ff95:d2::/32ff95:d2:ffff:ffff:ffff:ffff:ffff:ffff
212ff95:d3::/32ff95:d3:ffff:ffff:ffff:ffff:ffff:ffff
213ff95:d4::/32ff95:d4:ffff:ffff:ffff:ffff:ffff:ffff
214ff95:d5::/32ff95:d5:ffff:ffff:ffff:ffff:ffff:ffff
215ff95:d6::/32ff95:d6:ffff:ffff:ffff:ffff:ffff:ffff
216ff95:d7::/32ff95:d7:ffff:ffff:ffff:ffff:ffff:ffff
217ff95:d8::/32ff95:d8:ffff:ffff:ffff:ffff:ffff:ffff
218ff95:d9::/32ff95:d9:ffff:ffff:ffff:ffff:ffff:ffff
219ff95:da::/32ff95:da:ffff:ffff:ffff:ffff:ffff:ffff
220ff95:db::/32ff95:db:ffff:ffff:ffff:ffff:ffff:ffff
221ff95:dc::/32ff95:dc:ffff:ffff:ffff:ffff:ffff:ffff
222ff95:dd::/32ff95:dd:ffff:ffff:ffff:ffff:ffff:ffff
223ff95:de::/32ff95:de:ffff:ffff:ffff:ffff:ffff:ffff
224ff95:df::/32ff95:df:ffff:ffff:ffff:ffff:ffff:ffff
225ff95:e0::/32ff95:e0:ffff:ffff:ffff:ffff:ffff:ffff
226ff95:e1::/32ff95:e1:ffff:ffff:ffff:ffff:ffff:ffff
227ff95:e2::/32ff95:e2:ffff:ffff:ffff:ffff:ffff:ffff
228ff95:e3::/32ff95:e3:ffff:ffff:ffff:ffff:ffff:ffff
229ff95:e4::/32ff95:e4:ffff:ffff:ffff:ffff:ffff:ffff
230ff95:e5::/32ff95:e5:ffff:ffff:ffff:ffff:ffff:ffff
231ff95:e6::/32ff95:e6:ffff:ffff:ffff:ffff:ffff:ffff
232ff95:e7::/32ff95:e7:ffff:ffff:ffff:ffff:ffff:ffff
233ff95:e8::/32ff95:e8:ffff:ffff:ffff:ffff:ffff:ffff
234ff95:e9::/32ff95:e9:ffff:ffff:ffff:ffff:ffff:ffff
235ff95:ea::/32ff95:ea:ffff:ffff:ffff:ffff:ffff:ffff
236ff95:eb::/32ff95:eb:ffff:ffff:ffff:ffff:ffff:ffff
237ff95:ec::/32ff95:ec:ffff:ffff:ffff:ffff:ffff:ffff
238ff95:ed::/32ff95:ed:ffff:ffff:ffff:ffff:ffff:ffff
239ff95:ee::/32ff95:ee:ffff:ffff:ffff:ffff:ffff:ffff
240ff95:ef::/32ff95:ef:ffff:ffff:ffff:ffff:ffff:ffff
241ff95:f0::/32ff95:f0:ffff:ffff:ffff:ffff:ffff:ffff
242ff95:f1::/32ff95:f1:ffff:ffff:ffff:ffff:ffff:ffff
243ff95:f2::/32ff95:f2:ffff:ffff:ffff:ffff:ffff:ffff
244ff95:f3::/32ff95:f3:ffff:ffff:ffff:ffff:ffff:ffff
245ff95:f4::/32ff95:f4:ffff:ffff:ffff:ffff:ffff:ffff
246ff95:f5::/32ff95:f5:ffff:ffff:ffff:ffff:ffff:ffff
247ff95:f6::/32ff95:f6:ffff:ffff:ffff:ffff:ffff:ffff
248ff95:f7::/32ff95:f7:ffff:ffff:ffff:ffff:ffff:ffff
249ff95:f8::/32ff95:f8:ffff:ffff:ffff:ffff:ffff:ffff
250ff95:f9::/32ff95:f9:ffff:ffff:ffff:ffff:ffff:ffff
251ff95:fa::/32ff95:fa:ffff:ffff:ffff:ffff:ffff:ffff
252ff95:fb::/32ff95:fb:ffff:ffff:ffff:ffff:ffff:ffff
253ff95:fc::/32ff95:fc:ffff:ffff:ffff:ffff:ffff:ffff
254ff95:fd::/32ff95:fd:ffff:ffff:ffff:ffff:ffff:ffff
255ff95:fe::/32ff95:fe:ffff:ffff:ffff:ffff:ffff:ffff
256ff95:ff::/32ff95: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.