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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
ff53::/16
First address
ff53::
Last address
ff53: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
ff53:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
3.5.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)

ff53::/16 makes 65,536 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
1ff53::/32ff53:0:ffff:ffff:ffff:ffff:ffff:ffff
2ff53:1::/32ff53:1:ffff:ffff:ffff:ffff:ffff:ffff
3ff53:2::/32ff53:2:ffff:ffff:ffff:ffff:ffff:ffff
4ff53:3::/32ff53:3:ffff:ffff:ffff:ffff:ffff:ffff
5ff53:4::/32ff53:4:ffff:ffff:ffff:ffff:ffff:ffff
6ff53:5::/32ff53:5:ffff:ffff:ffff:ffff:ffff:ffff
7ff53:6::/32ff53:6:ffff:ffff:ffff:ffff:ffff:ffff
8ff53:7::/32ff53:7:ffff:ffff:ffff:ffff:ffff:ffff
9ff53:8::/32ff53:8:ffff:ffff:ffff:ffff:ffff:ffff
10ff53:9::/32ff53:9:ffff:ffff:ffff:ffff:ffff:ffff
11ff53:a::/32ff53:a:ffff:ffff:ffff:ffff:ffff:ffff
12ff53:b::/32ff53:b:ffff:ffff:ffff:ffff:ffff:ffff
13ff53:c::/32ff53:c:ffff:ffff:ffff:ffff:ffff:ffff
14ff53:d::/32ff53:d:ffff:ffff:ffff:ffff:ffff:ffff
15ff53:e::/32ff53:e:ffff:ffff:ffff:ffff:ffff:ffff
16ff53:f::/32ff53:f:ffff:ffff:ffff:ffff:ffff:ffff
17ff53:10::/32ff53:10:ffff:ffff:ffff:ffff:ffff:ffff
18ff53:11::/32ff53:11:ffff:ffff:ffff:ffff:ffff:ffff
19ff53:12::/32ff53:12:ffff:ffff:ffff:ffff:ffff:ffff
20ff53:13::/32ff53:13:ffff:ffff:ffff:ffff:ffff:ffff
21ff53:14::/32ff53:14:ffff:ffff:ffff:ffff:ffff:ffff
22ff53:15::/32ff53:15:ffff:ffff:ffff:ffff:ffff:ffff
23ff53:16::/32ff53:16:ffff:ffff:ffff:ffff:ffff:ffff
24ff53:17::/32ff53:17:ffff:ffff:ffff:ffff:ffff:ffff
25ff53:18::/32ff53:18:ffff:ffff:ffff:ffff:ffff:ffff
26ff53:19::/32ff53:19:ffff:ffff:ffff:ffff:ffff:ffff
27ff53:1a::/32ff53:1a:ffff:ffff:ffff:ffff:ffff:ffff
28ff53:1b::/32ff53:1b:ffff:ffff:ffff:ffff:ffff:ffff
29ff53:1c::/32ff53:1c:ffff:ffff:ffff:ffff:ffff:ffff
30ff53:1d::/32ff53:1d:ffff:ffff:ffff:ffff:ffff:ffff
31ff53:1e::/32ff53:1e:ffff:ffff:ffff:ffff:ffff:ffff
32ff53:1f::/32ff53:1f:ffff:ffff:ffff:ffff:ffff:ffff
33ff53:20::/32ff53:20:ffff:ffff:ffff:ffff:ffff:ffff
34ff53:21::/32ff53:21:ffff:ffff:ffff:ffff:ffff:ffff
35ff53:22::/32ff53:22:ffff:ffff:ffff:ffff:ffff:ffff
36ff53:23::/32ff53:23:ffff:ffff:ffff:ffff:ffff:ffff
37ff53:24::/32ff53:24:ffff:ffff:ffff:ffff:ffff:ffff
38ff53:25::/32ff53:25:ffff:ffff:ffff:ffff:ffff:ffff
39ff53:26::/32ff53:26:ffff:ffff:ffff:ffff:ffff:ffff
40ff53:27::/32ff53:27:ffff:ffff:ffff:ffff:ffff:ffff
41ff53:28::/32ff53:28:ffff:ffff:ffff:ffff:ffff:ffff
42ff53:29::/32ff53:29:ffff:ffff:ffff:ffff:ffff:ffff
43ff53:2a::/32ff53:2a:ffff:ffff:ffff:ffff:ffff:ffff
44ff53:2b::/32ff53:2b:ffff:ffff:ffff:ffff:ffff:ffff
45ff53:2c::/32ff53:2c:ffff:ffff:ffff:ffff:ffff:ffff
46ff53:2d::/32ff53:2d:ffff:ffff:ffff:ffff:ffff:ffff
47ff53:2e::/32ff53:2e:ffff:ffff:ffff:ffff:ffff:ffff
48ff53:2f::/32ff53:2f:ffff:ffff:ffff:ffff:ffff:ffff
49ff53:30::/32ff53:30:ffff:ffff:ffff:ffff:ffff:ffff
50ff53:31::/32ff53:31:ffff:ffff:ffff:ffff:ffff:ffff
51ff53:32::/32ff53:32:ffff:ffff:ffff:ffff:ffff:ffff
52ff53:33::/32ff53:33:ffff:ffff:ffff:ffff:ffff:ffff
53ff53:34::/32ff53:34:ffff:ffff:ffff:ffff:ffff:ffff
54ff53:35::/32ff53:35:ffff:ffff:ffff:ffff:ffff:ffff
55ff53:36::/32ff53:36:ffff:ffff:ffff:ffff:ffff:ffff
56ff53:37::/32ff53:37:ffff:ffff:ffff:ffff:ffff:ffff
57ff53:38::/32ff53:38:ffff:ffff:ffff:ffff:ffff:ffff
58ff53:39::/32ff53:39:ffff:ffff:ffff:ffff:ffff:ffff
59ff53:3a::/32ff53:3a:ffff:ffff:ffff:ffff:ffff:ffff
60ff53:3b::/32ff53:3b:ffff:ffff:ffff:ffff:ffff:ffff
61ff53:3c::/32ff53:3c:ffff:ffff:ffff:ffff:ffff:ffff
62ff53:3d::/32ff53:3d:ffff:ffff:ffff:ffff:ffff:ffff
63ff53:3e::/32ff53:3e:ffff:ffff:ffff:ffff:ffff:ffff
64ff53:3f::/32ff53:3f:ffff:ffff:ffff:ffff:ffff:ffff
65ff53:40::/32ff53:40:ffff:ffff:ffff:ffff:ffff:ffff
66ff53:41::/32ff53:41:ffff:ffff:ffff:ffff:ffff:ffff
67ff53:42::/32ff53:42:ffff:ffff:ffff:ffff:ffff:ffff
68ff53:43::/32ff53:43:ffff:ffff:ffff:ffff:ffff:ffff
69ff53:44::/32ff53:44:ffff:ffff:ffff:ffff:ffff:ffff
70ff53:45::/32ff53:45:ffff:ffff:ffff:ffff:ffff:ffff
71ff53:46::/32ff53:46:ffff:ffff:ffff:ffff:ffff:ffff
72ff53:47::/32ff53:47:ffff:ffff:ffff:ffff:ffff:ffff
73ff53:48::/32ff53:48:ffff:ffff:ffff:ffff:ffff:ffff
74ff53:49::/32ff53:49:ffff:ffff:ffff:ffff:ffff:ffff
75ff53:4a::/32ff53:4a:ffff:ffff:ffff:ffff:ffff:ffff
76ff53:4b::/32ff53:4b:ffff:ffff:ffff:ffff:ffff:ffff
77ff53:4c::/32ff53:4c:ffff:ffff:ffff:ffff:ffff:ffff
78ff53:4d::/32ff53:4d:ffff:ffff:ffff:ffff:ffff:ffff
79ff53:4e::/32ff53:4e:ffff:ffff:ffff:ffff:ffff:ffff
80ff53:4f::/32ff53:4f:ffff:ffff:ffff:ffff:ffff:ffff
81ff53:50::/32ff53:50:ffff:ffff:ffff:ffff:ffff:ffff
82ff53:51::/32ff53:51:ffff:ffff:ffff:ffff:ffff:ffff
83ff53:52::/32ff53:52:ffff:ffff:ffff:ffff:ffff:ffff
84ff53:53::/32ff53:53:ffff:ffff:ffff:ffff:ffff:ffff
85ff53:54::/32ff53:54:ffff:ffff:ffff:ffff:ffff:ffff
86ff53:55::/32ff53:55:ffff:ffff:ffff:ffff:ffff:ffff
87ff53:56::/32ff53:56:ffff:ffff:ffff:ffff:ffff:ffff
88ff53:57::/32ff53:57:ffff:ffff:ffff:ffff:ffff:ffff
89ff53:58::/32ff53:58:ffff:ffff:ffff:ffff:ffff:ffff
90ff53:59::/32ff53:59:ffff:ffff:ffff:ffff:ffff:ffff
91ff53:5a::/32ff53:5a:ffff:ffff:ffff:ffff:ffff:ffff
92ff53:5b::/32ff53:5b:ffff:ffff:ffff:ffff:ffff:ffff
93ff53:5c::/32ff53:5c:ffff:ffff:ffff:ffff:ffff:ffff
94ff53:5d::/32ff53:5d:ffff:ffff:ffff:ffff:ffff:ffff
95ff53:5e::/32ff53:5e:ffff:ffff:ffff:ffff:ffff:ffff
96ff53:5f::/32ff53:5f:ffff:ffff:ffff:ffff:ffff:ffff
97ff53:60::/32ff53:60:ffff:ffff:ffff:ffff:ffff:ffff
98ff53:61::/32ff53:61:ffff:ffff:ffff:ffff:ffff:ffff
99ff53:62::/32ff53:62:ffff:ffff:ffff:ffff:ffff:ffff
100ff53:63::/32ff53:63:ffff:ffff:ffff:ffff:ffff:ffff
101ff53:64::/32ff53:64:ffff:ffff:ffff:ffff:ffff:ffff
102ff53:65::/32ff53:65:ffff:ffff:ffff:ffff:ffff:ffff
103ff53:66::/32ff53:66:ffff:ffff:ffff:ffff:ffff:ffff
104ff53:67::/32ff53:67:ffff:ffff:ffff:ffff:ffff:ffff
105ff53:68::/32ff53:68:ffff:ffff:ffff:ffff:ffff:ffff
106ff53:69::/32ff53:69:ffff:ffff:ffff:ffff:ffff:ffff
107ff53:6a::/32ff53:6a:ffff:ffff:ffff:ffff:ffff:ffff
108ff53:6b::/32ff53:6b:ffff:ffff:ffff:ffff:ffff:ffff
109ff53:6c::/32ff53:6c:ffff:ffff:ffff:ffff:ffff:ffff
110ff53:6d::/32ff53:6d:ffff:ffff:ffff:ffff:ffff:ffff
111ff53:6e::/32ff53:6e:ffff:ffff:ffff:ffff:ffff:ffff
112ff53:6f::/32ff53:6f:ffff:ffff:ffff:ffff:ffff:ffff
113ff53:70::/32ff53:70:ffff:ffff:ffff:ffff:ffff:ffff
114ff53:71::/32ff53:71:ffff:ffff:ffff:ffff:ffff:ffff
115ff53:72::/32ff53:72:ffff:ffff:ffff:ffff:ffff:ffff
116ff53:73::/32ff53:73:ffff:ffff:ffff:ffff:ffff:ffff
117ff53:74::/32ff53:74:ffff:ffff:ffff:ffff:ffff:ffff
118ff53:75::/32ff53:75:ffff:ffff:ffff:ffff:ffff:ffff
119ff53:76::/32ff53:76:ffff:ffff:ffff:ffff:ffff:ffff
120ff53:77::/32ff53:77:ffff:ffff:ffff:ffff:ffff:ffff
121ff53:78::/32ff53:78:ffff:ffff:ffff:ffff:ffff:ffff
122ff53:79::/32ff53:79:ffff:ffff:ffff:ffff:ffff:ffff
123ff53:7a::/32ff53:7a:ffff:ffff:ffff:ffff:ffff:ffff
124ff53:7b::/32ff53:7b:ffff:ffff:ffff:ffff:ffff:ffff
125ff53:7c::/32ff53:7c:ffff:ffff:ffff:ffff:ffff:ffff
126ff53:7d::/32ff53:7d:ffff:ffff:ffff:ffff:ffff:ffff
127ff53:7e::/32ff53:7e:ffff:ffff:ffff:ffff:ffff:ffff
128ff53:7f::/32ff53:7f:ffff:ffff:ffff:ffff:ffff:ffff
129ff53:80::/32ff53:80:ffff:ffff:ffff:ffff:ffff:ffff
130ff53:81::/32ff53:81:ffff:ffff:ffff:ffff:ffff:ffff
131ff53:82::/32ff53:82:ffff:ffff:ffff:ffff:ffff:ffff
132ff53:83::/32ff53:83:ffff:ffff:ffff:ffff:ffff:ffff
133ff53:84::/32ff53:84:ffff:ffff:ffff:ffff:ffff:ffff
134ff53:85::/32ff53:85:ffff:ffff:ffff:ffff:ffff:ffff
135ff53:86::/32ff53:86:ffff:ffff:ffff:ffff:ffff:ffff
136ff53:87::/32ff53:87:ffff:ffff:ffff:ffff:ffff:ffff
137ff53:88::/32ff53:88:ffff:ffff:ffff:ffff:ffff:ffff
138ff53:89::/32ff53:89:ffff:ffff:ffff:ffff:ffff:ffff
139ff53:8a::/32ff53:8a:ffff:ffff:ffff:ffff:ffff:ffff
140ff53:8b::/32ff53:8b:ffff:ffff:ffff:ffff:ffff:ffff
141ff53:8c::/32ff53:8c:ffff:ffff:ffff:ffff:ffff:ffff
142ff53:8d::/32ff53:8d:ffff:ffff:ffff:ffff:ffff:ffff
143ff53:8e::/32ff53:8e:ffff:ffff:ffff:ffff:ffff:ffff
144ff53:8f::/32ff53:8f:ffff:ffff:ffff:ffff:ffff:ffff
145ff53:90::/32ff53:90:ffff:ffff:ffff:ffff:ffff:ffff
146ff53:91::/32ff53:91:ffff:ffff:ffff:ffff:ffff:ffff
147ff53:92::/32ff53:92:ffff:ffff:ffff:ffff:ffff:ffff
148ff53:93::/32ff53:93:ffff:ffff:ffff:ffff:ffff:ffff
149ff53:94::/32ff53:94:ffff:ffff:ffff:ffff:ffff:ffff
150ff53:95::/32ff53:95:ffff:ffff:ffff:ffff:ffff:ffff
151ff53:96::/32ff53:96:ffff:ffff:ffff:ffff:ffff:ffff
152ff53:97::/32ff53:97:ffff:ffff:ffff:ffff:ffff:ffff
153ff53:98::/32ff53:98:ffff:ffff:ffff:ffff:ffff:ffff
154ff53:99::/32ff53:99:ffff:ffff:ffff:ffff:ffff:ffff
155ff53:9a::/32ff53:9a:ffff:ffff:ffff:ffff:ffff:ffff
156ff53:9b::/32ff53:9b:ffff:ffff:ffff:ffff:ffff:ffff
157ff53:9c::/32ff53:9c:ffff:ffff:ffff:ffff:ffff:ffff
158ff53:9d::/32ff53:9d:ffff:ffff:ffff:ffff:ffff:ffff
159ff53:9e::/32ff53:9e:ffff:ffff:ffff:ffff:ffff:ffff
160ff53:9f::/32ff53:9f:ffff:ffff:ffff:ffff:ffff:ffff
161ff53:a0::/32ff53:a0:ffff:ffff:ffff:ffff:ffff:ffff
162ff53:a1::/32ff53:a1:ffff:ffff:ffff:ffff:ffff:ffff
163ff53:a2::/32ff53:a2:ffff:ffff:ffff:ffff:ffff:ffff
164ff53:a3::/32ff53:a3:ffff:ffff:ffff:ffff:ffff:ffff
165ff53:a4::/32ff53:a4:ffff:ffff:ffff:ffff:ffff:ffff
166ff53:a5::/32ff53:a5:ffff:ffff:ffff:ffff:ffff:ffff
167ff53:a6::/32ff53:a6:ffff:ffff:ffff:ffff:ffff:ffff
168ff53:a7::/32ff53:a7:ffff:ffff:ffff:ffff:ffff:ffff
169ff53:a8::/32ff53:a8:ffff:ffff:ffff:ffff:ffff:ffff
170ff53:a9::/32ff53:a9:ffff:ffff:ffff:ffff:ffff:ffff
171ff53:aa::/32ff53:aa:ffff:ffff:ffff:ffff:ffff:ffff
172ff53:ab::/32ff53:ab:ffff:ffff:ffff:ffff:ffff:ffff
173ff53:ac::/32ff53:ac:ffff:ffff:ffff:ffff:ffff:ffff
174ff53:ad::/32ff53:ad:ffff:ffff:ffff:ffff:ffff:ffff
175ff53:ae::/32ff53:ae:ffff:ffff:ffff:ffff:ffff:ffff
176ff53:af::/32ff53:af:ffff:ffff:ffff:ffff:ffff:ffff
177ff53:b0::/32ff53:b0:ffff:ffff:ffff:ffff:ffff:ffff
178ff53:b1::/32ff53:b1:ffff:ffff:ffff:ffff:ffff:ffff
179ff53:b2::/32ff53:b2:ffff:ffff:ffff:ffff:ffff:ffff
180ff53:b3::/32ff53:b3:ffff:ffff:ffff:ffff:ffff:ffff
181ff53:b4::/32ff53:b4:ffff:ffff:ffff:ffff:ffff:ffff
182ff53:b5::/32ff53:b5:ffff:ffff:ffff:ffff:ffff:ffff
183ff53:b6::/32ff53:b6:ffff:ffff:ffff:ffff:ffff:ffff
184ff53:b7::/32ff53:b7:ffff:ffff:ffff:ffff:ffff:ffff
185ff53:b8::/32ff53:b8:ffff:ffff:ffff:ffff:ffff:ffff
186ff53:b9::/32ff53:b9:ffff:ffff:ffff:ffff:ffff:ffff
187ff53:ba::/32ff53:ba:ffff:ffff:ffff:ffff:ffff:ffff
188ff53:bb::/32ff53:bb:ffff:ffff:ffff:ffff:ffff:ffff
189ff53:bc::/32ff53:bc:ffff:ffff:ffff:ffff:ffff:ffff
190ff53:bd::/32ff53:bd:ffff:ffff:ffff:ffff:ffff:ffff
191ff53:be::/32ff53:be:ffff:ffff:ffff:ffff:ffff:ffff
192ff53:bf::/32ff53:bf:ffff:ffff:ffff:ffff:ffff:ffff
193ff53:c0::/32ff53:c0:ffff:ffff:ffff:ffff:ffff:ffff
194ff53:c1::/32ff53:c1:ffff:ffff:ffff:ffff:ffff:ffff
195ff53:c2::/32ff53:c2:ffff:ffff:ffff:ffff:ffff:ffff
196ff53:c3::/32ff53:c3:ffff:ffff:ffff:ffff:ffff:ffff
197ff53:c4::/32ff53:c4:ffff:ffff:ffff:ffff:ffff:ffff
198ff53:c5::/32ff53:c5:ffff:ffff:ffff:ffff:ffff:ffff
199ff53:c6::/32ff53:c6:ffff:ffff:ffff:ffff:ffff:ffff
200ff53:c7::/32ff53:c7:ffff:ffff:ffff:ffff:ffff:ffff
201ff53:c8::/32ff53:c8:ffff:ffff:ffff:ffff:ffff:ffff
202ff53:c9::/32ff53:c9:ffff:ffff:ffff:ffff:ffff:ffff
203ff53:ca::/32ff53:ca:ffff:ffff:ffff:ffff:ffff:ffff
204ff53:cb::/32ff53:cb:ffff:ffff:ffff:ffff:ffff:ffff
205ff53:cc::/32ff53:cc:ffff:ffff:ffff:ffff:ffff:ffff
206ff53:cd::/32ff53:cd:ffff:ffff:ffff:ffff:ffff:ffff
207ff53:ce::/32ff53:ce:ffff:ffff:ffff:ffff:ffff:ffff
208ff53:cf::/32ff53:cf:ffff:ffff:ffff:ffff:ffff:ffff
209ff53:d0::/32ff53:d0:ffff:ffff:ffff:ffff:ffff:ffff
210ff53:d1::/32ff53:d1:ffff:ffff:ffff:ffff:ffff:ffff
211ff53:d2::/32ff53:d2:ffff:ffff:ffff:ffff:ffff:ffff
212ff53:d3::/32ff53:d3:ffff:ffff:ffff:ffff:ffff:ffff
213ff53:d4::/32ff53:d4:ffff:ffff:ffff:ffff:ffff:ffff
214ff53:d5::/32ff53:d5:ffff:ffff:ffff:ffff:ffff:ffff
215ff53:d6::/32ff53:d6:ffff:ffff:ffff:ffff:ffff:ffff
216ff53:d7::/32ff53:d7:ffff:ffff:ffff:ffff:ffff:ffff
217ff53:d8::/32ff53:d8:ffff:ffff:ffff:ffff:ffff:ffff
218ff53:d9::/32ff53:d9:ffff:ffff:ffff:ffff:ffff:ffff
219ff53:da::/32ff53:da:ffff:ffff:ffff:ffff:ffff:ffff
220ff53:db::/32ff53:db:ffff:ffff:ffff:ffff:ffff:ffff
221ff53:dc::/32ff53:dc:ffff:ffff:ffff:ffff:ffff:ffff
222ff53:dd::/32ff53:dd:ffff:ffff:ffff:ffff:ffff:ffff
223ff53:de::/32ff53:de:ffff:ffff:ffff:ffff:ffff:ffff
224ff53:df::/32ff53:df:ffff:ffff:ffff:ffff:ffff:ffff
225ff53:e0::/32ff53:e0:ffff:ffff:ffff:ffff:ffff:ffff
226ff53:e1::/32ff53:e1:ffff:ffff:ffff:ffff:ffff:ffff
227ff53:e2::/32ff53:e2:ffff:ffff:ffff:ffff:ffff:ffff
228ff53:e3::/32ff53:e3:ffff:ffff:ffff:ffff:ffff:ffff
229ff53:e4::/32ff53:e4:ffff:ffff:ffff:ffff:ffff:ffff
230ff53:e5::/32ff53:e5:ffff:ffff:ffff:ffff:ffff:ffff
231ff53:e6::/32ff53:e6:ffff:ffff:ffff:ffff:ffff:ffff
232ff53:e7::/32ff53:e7:ffff:ffff:ffff:ffff:ffff:ffff
233ff53:e8::/32ff53:e8:ffff:ffff:ffff:ffff:ffff:ffff
234ff53:e9::/32ff53:e9:ffff:ffff:ffff:ffff:ffff:ffff
235ff53:ea::/32ff53:ea:ffff:ffff:ffff:ffff:ffff:ffff
236ff53:eb::/32ff53:eb:ffff:ffff:ffff:ffff:ffff:ffff
237ff53:ec::/32ff53:ec:ffff:ffff:ffff:ffff:ffff:ffff
238ff53:ed::/32ff53:ed:ffff:ffff:ffff:ffff:ffff:ffff
239ff53:ee::/32ff53:ee:ffff:ffff:ffff:ffff:ffff:ffff
240ff53:ef::/32ff53:ef:ffff:ffff:ffff:ffff:ffff:ffff
241ff53:f0::/32ff53:f0:ffff:ffff:ffff:ffff:ffff:ffff
242ff53:f1::/32ff53:f1:ffff:ffff:ffff:ffff:ffff:ffff
243ff53:f2::/32ff53:f2:ffff:ffff:ffff:ffff:ffff:ffff
244ff53:f3::/32ff53:f3:ffff:ffff:ffff:ffff:ffff:ffff
245ff53:f4::/32ff53:f4:ffff:ffff:ffff:ffff:ffff:ffff
246ff53:f5::/32ff53:f5:ffff:ffff:ffff:ffff:ffff:ffff
247ff53:f6::/32ff53:f6:ffff:ffff:ffff:ffff:ffff:ffff
248ff53:f7::/32ff53:f7:ffff:ffff:ffff:ffff:ffff:ffff
249ff53:f8::/32ff53:f8:ffff:ffff:ffff:ffff:ffff:ffff
250ff53:f9::/32ff53:f9:ffff:ffff:ffff:ffff:ffff:ffff
251ff53:fa::/32ff53:fa:ffff:ffff:ffff:ffff:ffff:ffff
252ff53:fb::/32ff53:fb:ffff:ffff:ffff:ffff:ffff:ffff
253ff53:fc::/32ff53:fc:ffff:ffff:ffff:ffff:ffff:ffff
254ff53:fd::/32ff53:fd:ffff:ffff:ffff:ffff:ffff:ffff
255ff53:fe::/32ff53:fe:ffff:ffff:ffff:ffff:ffff:ffff
256ff53:ff::/32ff53: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.