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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/12
Addresses2^116
/64 networks2^52
Network
ff30::/12
First address
ff30::
Last address
ff3f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
83,076,749,736,557,242,056,487,941,267,521,536 (2^116)
/64 networks (LANs)
4,503,599,627,370,496 (2^52)
Full form
ff30:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
3.f.f.ip6.arpa
Split into smaller subnets/24
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

ff30::/12 makes 4,096 subnets of /24; the first 256 are listed.

Subnets
#SubnetLast address
1ff30::/24ff30:ff:ffff:ffff:ffff:ffff:ffff:ffff
2ff30:100::/24ff30:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3ff30:200::/24ff30:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4ff30:300::/24ff30:3ff:ffff:ffff:ffff:ffff:ffff:ffff
5ff30:400::/24ff30:4ff:ffff:ffff:ffff:ffff:ffff:ffff
6ff30:500::/24ff30:5ff:ffff:ffff:ffff:ffff:ffff:ffff
7ff30:600::/24ff30:6ff:ffff:ffff:ffff:ffff:ffff:ffff
8ff30:700::/24ff30:7ff:ffff:ffff:ffff:ffff:ffff:ffff
9ff30:800::/24ff30:8ff:ffff:ffff:ffff:ffff:ffff:ffff
10ff30:900::/24ff30:9ff:ffff:ffff:ffff:ffff:ffff:ffff
11ff30:a00::/24ff30:aff:ffff:ffff:ffff:ffff:ffff:ffff
12ff30:b00::/24ff30:bff:ffff:ffff:ffff:ffff:ffff:ffff
13ff30:c00::/24ff30:cff:ffff:ffff:ffff:ffff:ffff:ffff
14ff30:d00::/24ff30:dff:ffff:ffff:ffff:ffff:ffff:ffff
15ff30:e00::/24ff30:eff:ffff:ffff:ffff:ffff:ffff:ffff
16ff30:f00::/24ff30:fff:ffff:ffff:ffff:ffff:ffff:ffff
17ff30:1000::/24ff30:10ff:ffff:ffff:ffff:ffff:ffff:ffff
18ff30:1100::/24ff30:11ff:ffff:ffff:ffff:ffff:ffff:ffff
19ff30:1200::/24ff30:12ff:ffff:ffff:ffff:ffff:ffff:ffff
20ff30:1300::/24ff30:13ff:ffff:ffff:ffff:ffff:ffff:ffff
21ff30:1400::/24ff30:14ff:ffff:ffff:ffff:ffff:ffff:ffff
22ff30:1500::/24ff30:15ff:ffff:ffff:ffff:ffff:ffff:ffff
23ff30:1600::/24ff30:16ff:ffff:ffff:ffff:ffff:ffff:ffff
24ff30:1700::/24ff30:17ff:ffff:ffff:ffff:ffff:ffff:ffff
25ff30:1800::/24ff30:18ff:ffff:ffff:ffff:ffff:ffff:ffff
26ff30:1900::/24ff30:19ff:ffff:ffff:ffff:ffff:ffff:ffff
27ff30:1a00::/24ff30:1aff:ffff:ffff:ffff:ffff:ffff:ffff
28ff30:1b00::/24ff30:1bff:ffff:ffff:ffff:ffff:ffff:ffff
29ff30:1c00::/24ff30:1cff:ffff:ffff:ffff:ffff:ffff:ffff
30ff30:1d00::/24ff30:1dff:ffff:ffff:ffff:ffff:ffff:ffff
31ff30:1e00::/24ff30:1eff:ffff:ffff:ffff:ffff:ffff:ffff
32ff30:1f00::/24ff30:1fff:ffff:ffff:ffff:ffff:ffff:ffff
33ff30:2000::/24ff30:20ff:ffff:ffff:ffff:ffff:ffff:ffff
34ff30:2100::/24ff30:21ff:ffff:ffff:ffff:ffff:ffff:ffff
35ff30:2200::/24ff30:22ff:ffff:ffff:ffff:ffff:ffff:ffff
36ff30:2300::/24ff30:23ff:ffff:ffff:ffff:ffff:ffff:ffff
37ff30:2400::/24ff30:24ff:ffff:ffff:ffff:ffff:ffff:ffff
38ff30:2500::/24ff30:25ff:ffff:ffff:ffff:ffff:ffff:ffff
39ff30:2600::/24ff30:26ff:ffff:ffff:ffff:ffff:ffff:ffff
40ff30:2700::/24ff30:27ff:ffff:ffff:ffff:ffff:ffff:ffff
41ff30:2800::/24ff30:28ff:ffff:ffff:ffff:ffff:ffff:ffff
42ff30:2900::/24ff30:29ff:ffff:ffff:ffff:ffff:ffff:ffff
43ff30:2a00::/24ff30:2aff:ffff:ffff:ffff:ffff:ffff:ffff
44ff30:2b00::/24ff30:2bff:ffff:ffff:ffff:ffff:ffff:ffff
45ff30:2c00::/24ff30:2cff:ffff:ffff:ffff:ffff:ffff:ffff
46ff30:2d00::/24ff30:2dff:ffff:ffff:ffff:ffff:ffff:ffff
47ff30:2e00::/24ff30:2eff:ffff:ffff:ffff:ffff:ffff:ffff
48ff30:2f00::/24ff30:2fff:ffff:ffff:ffff:ffff:ffff:ffff
49ff30:3000::/24ff30:30ff:ffff:ffff:ffff:ffff:ffff:ffff
50ff30:3100::/24ff30:31ff:ffff:ffff:ffff:ffff:ffff:ffff
51ff30:3200::/24ff30:32ff:ffff:ffff:ffff:ffff:ffff:ffff
52ff30:3300::/24ff30:33ff:ffff:ffff:ffff:ffff:ffff:ffff
53ff30:3400::/24ff30:34ff:ffff:ffff:ffff:ffff:ffff:ffff
54ff30:3500::/24ff30:35ff:ffff:ffff:ffff:ffff:ffff:ffff
55ff30:3600::/24ff30:36ff:ffff:ffff:ffff:ffff:ffff:ffff
56ff30:3700::/24ff30:37ff:ffff:ffff:ffff:ffff:ffff:ffff
57ff30:3800::/24ff30:38ff:ffff:ffff:ffff:ffff:ffff:ffff
58ff30:3900::/24ff30:39ff:ffff:ffff:ffff:ffff:ffff:ffff
59ff30:3a00::/24ff30:3aff:ffff:ffff:ffff:ffff:ffff:ffff
60ff30:3b00::/24ff30:3bff:ffff:ffff:ffff:ffff:ffff:ffff
61ff30:3c00::/24ff30:3cff:ffff:ffff:ffff:ffff:ffff:ffff
62ff30:3d00::/24ff30:3dff:ffff:ffff:ffff:ffff:ffff:ffff
63ff30:3e00::/24ff30:3eff:ffff:ffff:ffff:ffff:ffff:ffff
64ff30:3f00::/24ff30:3fff:ffff:ffff:ffff:ffff:ffff:ffff
65ff30:4000::/24ff30:40ff:ffff:ffff:ffff:ffff:ffff:ffff
66ff30:4100::/24ff30:41ff:ffff:ffff:ffff:ffff:ffff:ffff
67ff30:4200::/24ff30:42ff:ffff:ffff:ffff:ffff:ffff:ffff
68ff30:4300::/24ff30:43ff:ffff:ffff:ffff:ffff:ffff:ffff
69ff30:4400::/24ff30:44ff:ffff:ffff:ffff:ffff:ffff:ffff
70ff30:4500::/24ff30:45ff:ffff:ffff:ffff:ffff:ffff:ffff
71ff30:4600::/24ff30:46ff:ffff:ffff:ffff:ffff:ffff:ffff
72ff30:4700::/24ff30:47ff:ffff:ffff:ffff:ffff:ffff:ffff
73ff30:4800::/24ff30:48ff:ffff:ffff:ffff:ffff:ffff:ffff
74ff30:4900::/24ff30:49ff:ffff:ffff:ffff:ffff:ffff:ffff
75ff30:4a00::/24ff30:4aff:ffff:ffff:ffff:ffff:ffff:ffff
76ff30:4b00::/24ff30:4bff:ffff:ffff:ffff:ffff:ffff:ffff
77ff30:4c00::/24ff30:4cff:ffff:ffff:ffff:ffff:ffff:ffff
78ff30:4d00::/24ff30:4dff:ffff:ffff:ffff:ffff:ffff:ffff
79ff30:4e00::/24ff30:4eff:ffff:ffff:ffff:ffff:ffff:ffff
80ff30:4f00::/24ff30:4fff:ffff:ffff:ffff:ffff:ffff:ffff
81ff30:5000::/24ff30:50ff:ffff:ffff:ffff:ffff:ffff:ffff
82ff30:5100::/24ff30:51ff:ffff:ffff:ffff:ffff:ffff:ffff
83ff30:5200::/24ff30:52ff:ffff:ffff:ffff:ffff:ffff:ffff
84ff30:5300::/24ff30:53ff:ffff:ffff:ffff:ffff:ffff:ffff
85ff30:5400::/24ff30:54ff:ffff:ffff:ffff:ffff:ffff:ffff
86ff30:5500::/24ff30:55ff:ffff:ffff:ffff:ffff:ffff:ffff
87ff30:5600::/24ff30:56ff:ffff:ffff:ffff:ffff:ffff:ffff
88ff30:5700::/24ff30:57ff:ffff:ffff:ffff:ffff:ffff:ffff
89ff30:5800::/24ff30:58ff:ffff:ffff:ffff:ffff:ffff:ffff
90ff30:5900::/24ff30:59ff:ffff:ffff:ffff:ffff:ffff:ffff
91ff30:5a00::/24ff30:5aff:ffff:ffff:ffff:ffff:ffff:ffff
92ff30:5b00::/24ff30:5bff:ffff:ffff:ffff:ffff:ffff:ffff
93ff30:5c00::/24ff30:5cff:ffff:ffff:ffff:ffff:ffff:ffff
94ff30:5d00::/24ff30:5dff:ffff:ffff:ffff:ffff:ffff:ffff
95ff30:5e00::/24ff30:5eff:ffff:ffff:ffff:ffff:ffff:ffff
96ff30:5f00::/24ff30:5fff:ffff:ffff:ffff:ffff:ffff:ffff
97ff30:6000::/24ff30:60ff:ffff:ffff:ffff:ffff:ffff:ffff
98ff30:6100::/24ff30:61ff:ffff:ffff:ffff:ffff:ffff:ffff
99ff30:6200::/24ff30:62ff:ffff:ffff:ffff:ffff:ffff:ffff
100ff30:6300::/24ff30:63ff:ffff:ffff:ffff:ffff:ffff:ffff
101ff30:6400::/24ff30:64ff:ffff:ffff:ffff:ffff:ffff:ffff
102ff30:6500::/24ff30:65ff:ffff:ffff:ffff:ffff:ffff:ffff
103ff30:6600::/24ff30:66ff:ffff:ffff:ffff:ffff:ffff:ffff
104ff30:6700::/24ff30:67ff:ffff:ffff:ffff:ffff:ffff:ffff
105ff30:6800::/24ff30:68ff:ffff:ffff:ffff:ffff:ffff:ffff
106ff30:6900::/24ff30:69ff:ffff:ffff:ffff:ffff:ffff:ffff
107ff30:6a00::/24ff30:6aff:ffff:ffff:ffff:ffff:ffff:ffff
108ff30:6b00::/24ff30:6bff:ffff:ffff:ffff:ffff:ffff:ffff
109ff30:6c00::/24ff30:6cff:ffff:ffff:ffff:ffff:ffff:ffff
110ff30:6d00::/24ff30:6dff:ffff:ffff:ffff:ffff:ffff:ffff
111ff30:6e00::/24ff30:6eff:ffff:ffff:ffff:ffff:ffff:ffff
112ff30:6f00::/24ff30:6fff:ffff:ffff:ffff:ffff:ffff:ffff
113ff30:7000::/24ff30:70ff:ffff:ffff:ffff:ffff:ffff:ffff
114ff30:7100::/24ff30:71ff:ffff:ffff:ffff:ffff:ffff:ffff
115ff30:7200::/24ff30:72ff:ffff:ffff:ffff:ffff:ffff:ffff
116ff30:7300::/24ff30:73ff:ffff:ffff:ffff:ffff:ffff:ffff
117ff30:7400::/24ff30:74ff:ffff:ffff:ffff:ffff:ffff:ffff
118ff30:7500::/24ff30:75ff:ffff:ffff:ffff:ffff:ffff:ffff
119ff30:7600::/24ff30:76ff:ffff:ffff:ffff:ffff:ffff:ffff
120ff30:7700::/24ff30:77ff:ffff:ffff:ffff:ffff:ffff:ffff
121ff30:7800::/24ff30:78ff:ffff:ffff:ffff:ffff:ffff:ffff
122ff30:7900::/24ff30:79ff:ffff:ffff:ffff:ffff:ffff:ffff
123ff30:7a00::/24ff30:7aff:ffff:ffff:ffff:ffff:ffff:ffff
124ff30:7b00::/24ff30:7bff:ffff:ffff:ffff:ffff:ffff:ffff
125ff30:7c00::/24ff30:7cff:ffff:ffff:ffff:ffff:ffff:ffff
126ff30:7d00::/24ff30:7dff:ffff:ffff:ffff:ffff:ffff:ffff
127ff30:7e00::/24ff30:7eff:ffff:ffff:ffff:ffff:ffff:ffff
128ff30:7f00::/24ff30:7fff:ffff:ffff:ffff:ffff:ffff:ffff
129ff30:8000::/24ff30:80ff:ffff:ffff:ffff:ffff:ffff:ffff
130ff30:8100::/24ff30:81ff:ffff:ffff:ffff:ffff:ffff:ffff
131ff30:8200::/24ff30:82ff:ffff:ffff:ffff:ffff:ffff:ffff
132ff30:8300::/24ff30:83ff:ffff:ffff:ffff:ffff:ffff:ffff
133ff30:8400::/24ff30:84ff:ffff:ffff:ffff:ffff:ffff:ffff
134ff30:8500::/24ff30:85ff:ffff:ffff:ffff:ffff:ffff:ffff
135ff30:8600::/24ff30:86ff:ffff:ffff:ffff:ffff:ffff:ffff
136ff30:8700::/24ff30:87ff:ffff:ffff:ffff:ffff:ffff:ffff
137ff30:8800::/24ff30:88ff:ffff:ffff:ffff:ffff:ffff:ffff
138ff30:8900::/24ff30:89ff:ffff:ffff:ffff:ffff:ffff:ffff
139ff30:8a00::/24ff30:8aff:ffff:ffff:ffff:ffff:ffff:ffff
140ff30:8b00::/24ff30:8bff:ffff:ffff:ffff:ffff:ffff:ffff
141ff30:8c00::/24ff30:8cff:ffff:ffff:ffff:ffff:ffff:ffff
142ff30:8d00::/24ff30:8dff:ffff:ffff:ffff:ffff:ffff:ffff
143ff30:8e00::/24ff30:8eff:ffff:ffff:ffff:ffff:ffff:ffff
144ff30:8f00::/24ff30:8fff:ffff:ffff:ffff:ffff:ffff:ffff
145ff30:9000::/24ff30:90ff:ffff:ffff:ffff:ffff:ffff:ffff
146ff30:9100::/24ff30:91ff:ffff:ffff:ffff:ffff:ffff:ffff
147ff30:9200::/24ff30:92ff:ffff:ffff:ffff:ffff:ffff:ffff
148ff30:9300::/24ff30:93ff:ffff:ffff:ffff:ffff:ffff:ffff
149ff30:9400::/24ff30:94ff:ffff:ffff:ffff:ffff:ffff:ffff
150ff30:9500::/24ff30:95ff:ffff:ffff:ffff:ffff:ffff:ffff
151ff30:9600::/24ff30:96ff:ffff:ffff:ffff:ffff:ffff:ffff
152ff30:9700::/24ff30:97ff:ffff:ffff:ffff:ffff:ffff:ffff
153ff30:9800::/24ff30:98ff:ffff:ffff:ffff:ffff:ffff:ffff
154ff30:9900::/24ff30:99ff:ffff:ffff:ffff:ffff:ffff:ffff
155ff30:9a00::/24ff30:9aff:ffff:ffff:ffff:ffff:ffff:ffff
156ff30:9b00::/24ff30:9bff:ffff:ffff:ffff:ffff:ffff:ffff
157ff30:9c00::/24ff30:9cff:ffff:ffff:ffff:ffff:ffff:ffff
158ff30:9d00::/24ff30:9dff:ffff:ffff:ffff:ffff:ffff:ffff
159ff30:9e00::/24ff30:9eff:ffff:ffff:ffff:ffff:ffff:ffff
160ff30:9f00::/24ff30:9fff:ffff:ffff:ffff:ffff:ffff:ffff
161ff30:a000::/24ff30:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
162ff30:a100::/24ff30:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
163ff30:a200::/24ff30:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
164ff30:a300::/24ff30:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
165ff30:a400::/24ff30:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
166ff30:a500::/24ff30:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
167ff30:a600::/24ff30:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
168ff30:a700::/24ff30:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
169ff30:a800::/24ff30:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
170ff30:a900::/24ff30:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
171ff30:aa00::/24ff30:aaff:ffff:ffff:ffff:ffff:ffff:ffff
172ff30:ab00::/24ff30:abff:ffff:ffff:ffff:ffff:ffff:ffff
173ff30:ac00::/24ff30:acff:ffff:ffff:ffff:ffff:ffff:ffff
174ff30:ad00::/24ff30:adff:ffff:ffff:ffff:ffff:ffff:ffff
175ff30:ae00::/24ff30:aeff:ffff:ffff:ffff:ffff:ffff:ffff
176ff30:af00::/24ff30:afff:ffff:ffff:ffff:ffff:ffff:ffff
177ff30:b000::/24ff30:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
178ff30:b100::/24ff30:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
179ff30:b200::/24ff30:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
180ff30:b300::/24ff30:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
181ff30:b400::/24ff30:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
182ff30:b500::/24ff30:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
183ff30:b600::/24ff30:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
184ff30:b700::/24ff30:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
185ff30:b800::/24ff30:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
186ff30:b900::/24ff30:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
187ff30:ba00::/24ff30:baff:ffff:ffff:ffff:ffff:ffff:ffff
188ff30:bb00::/24ff30:bbff:ffff:ffff:ffff:ffff:ffff:ffff
189ff30:bc00::/24ff30:bcff:ffff:ffff:ffff:ffff:ffff:ffff
190ff30:bd00::/24ff30:bdff:ffff:ffff:ffff:ffff:ffff:ffff
191ff30:be00::/24ff30:beff:ffff:ffff:ffff:ffff:ffff:ffff
192ff30:bf00::/24ff30:bfff:ffff:ffff:ffff:ffff:ffff:ffff
193ff30:c000::/24ff30:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
194ff30:c100::/24ff30:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
195ff30:c200::/24ff30:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
196ff30:c300::/24ff30:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
197ff30:c400::/24ff30:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
198ff30:c500::/24ff30:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
199ff30:c600::/24ff30:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
200ff30:c700::/24ff30:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
201ff30:c800::/24ff30:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
202ff30:c900::/24ff30:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
203ff30:ca00::/24ff30:caff:ffff:ffff:ffff:ffff:ffff:ffff
204ff30:cb00::/24ff30:cbff:ffff:ffff:ffff:ffff:ffff:ffff
205ff30:cc00::/24ff30:ccff:ffff:ffff:ffff:ffff:ffff:ffff
206ff30:cd00::/24ff30:cdff:ffff:ffff:ffff:ffff:ffff:ffff
207ff30:ce00::/24ff30:ceff:ffff:ffff:ffff:ffff:ffff:ffff
208ff30:cf00::/24ff30:cfff:ffff:ffff:ffff:ffff:ffff:ffff
209ff30:d000::/24ff30:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
210ff30:d100::/24ff30:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
211ff30:d200::/24ff30:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
212ff30:d300::/24ff30:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
213ff30:d400::/24ff30:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
214ff30:d500::/24ff30:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
215ff30:d600::/24ff30:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
216ff30:d700::/24ff30:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
217ff30:d800::/24ff30:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
218ff30:d900::/24ff30:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
219ff30:da00::/24ff30:daff:ffff:ffff:ffff:ffff:ffff:ffff
220ff30:db00::/24ff30:dbff:ffff:ffff:ffff:ffff:ffff:ffff
221ff30:dc00::/24ff30:dcff:ffff:ffff:ffff:ffff:ffff:ffff
222ff30:dd00::/24ff30:ddff:ffff:ffff:ffff:ffff:ffff:ffff
223ff30:de00::/24ff30:deff:ffff:ffff:ffff:ffff:ffff:ffff
224ff30:df00::/24ff30:dfff:ffff:ffff:ffff:ffff:ffff:ffff
225ff30:e000::/24ff30:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
226ff30:e100::/24ff30:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
227ff30:e200::/24ff30:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
228ff30:e300::/24ff30:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
229ff30:e400::/24ff30:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
230ff30:e500::/24ff30:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
231ff30:e600::/24ff30:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
232ff30:e700::/24ff30:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
233ff30:e800::/24ff30:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
234ff30:e900::/24ff30:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
235ff30:ea00::/24ff30:eaff:ffff:ffff:ffff:ffff:ffff:ffff
236ff30:eb00::/24ff30:ebff:ffff:ffff:ffff:ffff:ffff:ffff
237ff30:ec00::/24ff30:ecff:ffff:ffff:ffff:ffff:ffff:ffff
238ff30:ed00::/24ff30:edff:ffff:ffff:ffff:ffff:ffff:ffff
239ff30:ee00::/24ff30:eeff:ffff:ffff:ffff:ffff:ffff:ffff
240ff30:ef00::/24ff30:efff:ffff:ffff:ffff:ffff:ffff:ffff
241ff30:f000::/24ff30:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
242ff30:f100::/24ff30:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
243ff30:f200::/24ff30:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
244ff30:f300::/24ff30:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
245ff30:f400::/24ff30:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
246ff30:f500::/24ff30:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
247ff30:f600::/24ff30:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
248ff30:f700::/24ff30:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
249ff30:f800::/24ff30:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
250ff30:f900::/24ff30:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
251ff30:fa00::/24ff30:faff:ffff:ffff:ffff:ffff:ffff:ffff
252ff30:fb00::/24ff30:fbff:ffff:ffff:ffff:ffff:ffff:ffff
253ff30:fc00::/24ff30:fcff:ffff:ffff:ffff:ffff:ffff:ffff
254ff30:fd00::/24ff30:fdff:ffff:ffff:ffff:ffff:ffff:ffff
255ff30:fe00::/24ff30:feff:ffff:ffff:ffff:ffff:ffff:ffff
256ff30:ff00::/24ff30:ffff: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.