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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
ff69::/16
First address
ff69::
Last address
ff69: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
ff69:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
9.6.f.f.ip6.arpa
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

ff69::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
1ff69::/24ff69:ff:ffff:ffff:ffff:ffff:ffff:ffff
2ff69:100::/24ff69:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3ff69:200::/24ff69:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4ff69:300::/24ff69:3ff:ffff:ffff:ffff:ffff:ffff:ffff
5ff69:400::/24ff69:4ff:ffff:ffff:ffff:ffff:ffff:ffff
6ff69:500::/24ff69:5ff:ffff:ffff:ffff:ffff:ffff:ffff
7ff69:600::/24ff69:6ff:ffff:ffff:ffff:ffff:ffff:ffff
8ff69:700::/24ff69:7ff:ffff:ffff:ffff:ffff:ffff:ffff
9ff69:800::/24ff69:8ff:ffff:ffff:ffff:ffff:ffff:ffff
10ff69:900::/24ff69:9ff:ffff:ffff:ffff:ffff:ffff:ffff
11ff69:a00::/24ff69:aff:ffff:ffff:ffff:ffff:ffff:ffff
12ff69:b00::/24ff69:bff:ffff:ffff:ffff:ffff:ffff:ffff
13ff69:c00::/24ff69:cff:ffff:ffff:ffff:ffff:ffff:ffff
14ff69:d00::/24ff69:dff:ffff:ffff:ffff:ffff:ffff:ffff
15ff69:e00::/24ff69:eff:ffff:ffff:ffff:ffff:ffff:ffff
16ff69:f00::/24ff69:fff:ffff:ffff:ffff:ffff:ffff:ffff
17ff69:1000::/24ff69:10ff:ffff:ffff:ffff:ffff:ffff:ffff
18ff69:1100::/24ff69:11ff:ffff:ffff:ffff:ffff:ffff:ffff
19ff69:1200::/24ff69:12ff:ffff:ffff:ffff:ffff:ffff:ffff
20ff69:1300::/24ff69:13ff:ffff:ffff:ffff:ffff:ffff:ffff
21ff69:1400::/24ff69:14ff:ffff:ffff:ffff:ffff:ffff:ffff
22ff69:1500::/24ff69:15ff:ffff:ffff:ffff:ffff:ffff:ffff
23ff69:1600::/24ff69:16ff:ffff:ffff:ffff:ffff:ffff:ffff
24ff69:1700::/24ff69:17ff:ffff:ffff:ffff:ffff:ffff:ffff
25ff69:1800::/24ff69:18ff:ffff:ffff:ffff:ffff:ffff:ffff
26ff69:1900::/24ff69:19ff:ffff:ffff:ffff:ffff:ffff:ffff
27ff69:1a00::/24ff69:1aff:ffff:ffff:ffff:ffff:ffff:ffff
28ff69:1b00::/24ff69:1bff:ffff:ffff:ffff:ffff:ffff:ffff
29ff69:1c00::/24ff69:1cff:ffff:ffff:ffff:ffff:ffff:ffff
30ff69:1d00::/24ff69:1dff:ffff:ffff:ffff:ffff:ffff:ffff
31ff69:1e00::/24ff69:1eff:ffff:ffff:ffff:ffff:ffff:ffff
32ff69:1f00::/24ff69:1fff:ffff:ffff:ffff:ffff:ffff:ffff
33ff69:2000::/24ff69:20ff:ffff:ffff:ffff:ffff:ffff:ffff
34ff69:2100::/24ff69:21ff:ffff:ffff:ffff:ffff:ffff:ffff
35ff69:2200::/24ff69:22ff:ffff:ffff:ffff:ffff:ffff:ffff
36ff69:2300::/24ff69:23ff:ffff:ffff:ffff:ffff:ffff:ffff
37ff69:2400::/24ff69:24ff:ffff:ffff:ffff:ffff:ffff:ffff
38ff69:2500::/24ff69:25ff:ffff:ffff:ffff:ffff:ffff:ffff
39ff69:2600::/24ff69:26ff:ffff:ffff:ffff:ffff:ffff:ffff
40ff69:2700::/24ff69:27ff:ffff:ffff:ffff:ffff:ffff:ffff
41ff69:2800::/24ff69:28ff:ffff:ffff:ffff:ffff:ffff:ffff
42ff69:2900::/24ff69:29ff:ffff:ffff:ffff:ffff:ffff:ffff
43ff69:2a00::/24ff69:2aff:ffff:ffff:ffff:ffff:ffff:ffff
44ff69:2b00::/24ff69:2bff:ffff:ffff:ffff:ffff:ffff:ffff
45ff69:2c00::/24ff69:2cff:ffff:ffff:ffff:ffff:ffff:ffff
46ff69:2d00::/24ff69:2dff:ffff:ffff:ffff:ffff:ffff:ffff
47ff69:2e00::/24ff69:2eff:ffff:ffff:ffff:ffff:ffff:ffff
48ff69:2f00::/24ff69:2fff:ffff:ffff:ffff:ffff:ffff:ffff
49ff69:3000::/24ff69:30ff:ffff:ffff:ffff:ffff:ffff:ffff
50ff69:3100::/24ff69:31ff:ffff:ffff:ffff:ffff:ffff:ffff
51ff69:3200::/24ff69:32ff:ffff:ffff:ffff:ffff:ffff:ffff
52ff69:3300::/24ff69:33ff:ffff:ffff:ffff:ffff:ffff:ffff
53ff69:3400::/24ff69:34ff:ffff:ffff:ffff:ffff:ffff:ffff
54ff69:3500::/24ff69:35ff:ffff:ffff:ffff:ffff:ffff:ffff
55ff69:3600::/24ff69:36ff:ffff:ffff:ffff:ffff:ffff:ffff
56ff69:3700::/24ff69:37ff:ffff:ffff:ffff:ffff:ffff:ffff
57ff69:3800::/24ff69:38ff:ffff:ffff:ffff:ffff:ffff:ffff
58ff69:3900::/24ff69:39ff:ffff:ffff:ffff:ffff:ffff:ffff
59ff69:3a00::/24ff69:3aff:ffff:ffff:ffff:ffff:ffff:ffff
60ff69:3b00::/24ff69:3bff:ffff:ffff:ffff:ffff:ffff:ffff
61ff69:3c00::/24ff69:3cff:ffff:ffff:ffff:ffff:ffff:ffff
62ff69:3d00::/24ff69:3dff:ffff:ffff:ffff:ffff:ffff:ffff
63ff69:3e00::/24ff69:3eff:ffff:ffff:ffff:ffff:ffff:ffff
64ff69:3f00::/24ff69:3fff:ffff:ffff:ffff:ffff:ffff:ffff
65ff69:4000::/24ff69:40ff:ffff:ffff:ffff:ffff:ffff:ffff
66ff69:4100::/24ff69:41ff:ffff:ffff:ffff:ffff:ffff:ffff
67ff69:4200::/24ff69:42ff:ffff:ffff:ffff:ffff:ffff:ffff
68ff69:4300::/24ff69:43ff:ffff:ffff:ffff:ffff:ffff:ffff
69ff69:4400::/24ff69:44ff:ffff:ffff:ffff:ffff:ffff:ffff
70ff69:4500::/24ff69:45ff:ffff:ffff:ffff:ffff:ffff:ffff
71ff69:4600::/24ff69:46ff:ffff:ffff:ffff:ffff:ffff:ffff
72ff69:4700::/24ff69:47ff:ffff:ffff:ffff:ffff:ffff:ffff
73ff69:4800::/24ff69:48ff:ffff:ffff:ffff:ffff:ffff:ffff
74ff69:4900::/24ff69:49ff:ffff:ffff:ffff:ffff:ffff:ffff
75ff69:4a00::/24ff69:4aff:ffff:ffff:ffff:ffff:ffff:ffff
76ff69:4b00::/24ff69:4bff:ffff:ffff:ffff:ffff:ffff:ffff
77ff69:4c00::/24ff69:4cff:ffff:ffff:ffff:ffff:ffff:ffff
78ff69:4d00::/24ff69:4dff:ffff:ffff:ffff:ffff:ffff:ffff
79ff69:4e00::/24ff69:4eff:ffff:ffff:ffff:ffff:ffff:ffff
80ff69:4f00::/24ff69:4fff:ffff:ffff:ffff:ffff:ffff:ffff
81ff69:5000::/24ff69:50ff:ffff:ffff:ffff:ffff:ffff:ffff
82ff69:5100::/24ff69:51ff:ffff:ffff:ffff:ffff:ffff:ffff
83ff69:5200::/24ff69:52ff:ffff:ffff:ffff:ffff:ffff:ffff
84ff69:5300::/24ff69:53ff:ffff:ffff:ffff:ffff:ffff:ffff
85ff69:5400::/24ff69:54ff:ffff:ffff:ffff:ffff:ffff:ffff
86ff69:5500::/24ff69:55ff:ffff:ffff:ffff:ffff:ffff:ffff
87ff69:5600::/24ff69:56ff:ffff:ffff:ffff:ffff:ffff:ffff
88ff69:5700::/24ff69:57ff:ffff:ffff:ffff:ffff:ffff:ffff
89ff69:5800::/24ff69:58ff:ffff:ffff:ffff:ffff:ffff:ffff
90ff69:5900::/24ff69:59ff:ffff:ffff:ffff:ffff:ffff:ffff
91ff69:5a00::/24ff69:5aff:ffff:ffff:ffff:ffff:ffff:ffff
92ff69:5b00::/24ff69:5bff:ffff:ffff:ffff:ffff:ffff:ffff
93ff69:5c00::/24ff69:5cff:ffff:ffff:ffff:ffff:ffff:ffff
94ff69:5d00::/24ff69:5dff:ffff:ffff:ffff:ffff:ffff:ffff
95ff69:5e00::/24ff69:5eff:ffff:ffff:ffff:ffff:ffff:ffff
96ff69:5f00::/24ff69:5fff:ffff:ffff:ffff:ffff:ffff:ffff
97ff69:6000::/24ff69:60ff:ffff:ffff:ffff:ffff:ffff:ffff
98ff69:6100::/24ff69:61ff:ffff:ffff:ffff:ffff:ffff:ffff
99ff69:6200::/24ff69:62ff:ffff:ffff:ffff:ffff:ffff:ffff
100ff69:6300::/24ff69:63ff:ffff:ffff:ffff:ffff:ffff:ffff
101ff69:6400::/24ff69:64ff:ffff:ffff:ffff:ffff:ffff:ffff
102ff69:6500::/24ff69:65ff:ffff:ffff:ffff:ffff:ffff:ffff
103ff69:6600::/24ff69:66ff:ffff:ffff:ffff:ffff:ffff:ffff
104ff69:6700::/24ff69:67ff:ffff:ffff:ffff:ffff:ffff:ffff
105ff69:6800::/24ff69:68ff:ffff:ffff:ffff:ffff:ffff:ffff
106ff69:6900::/24ff69:69ff:ffff:ffff:ffff:ffff:ffff:ffff
107ff69:6a00::/24ff69:6aff:ffff:ffff:ffff:ffff:ffff:ffff
108ff69:6b00::/24ff69:6bff:ffff:ffff:ffff:ffff:ffff:ffff
109ff69:6c00::/24ff69:6cff:ffff:ffff:ffff:ffff:ffff:ffff
110ff69:6d00::/24ff69:6dff:ffff:ffff:ffff:ffff:ffff:ffff
111ff69:6e00::/24ff69:6eff:ffff:ffff:ffff:ffff:ffff:ffff
112ff69:6f00::/24ff69:6fff:ffff:ffff:ffff:ffff:ffff:ffff
113ff69:7000::/24ff69:70ff:ffff:ffff:ffff:ffff:ffff:ffff
114ff69:7100::/24ff69:71ff:ffff:ffff:ffff:ffff:ffff:ffff
115ff69:7200::/24ff69:72ff:ffff:ffff:ffff:ffff:ffff:ffff
116ff69:7300::/24ff69:73ff:ffff:ffff:ffff:ffff:ffff:ffff
117ff69:7400::/24ff69:74ff:ffff:ffff:ffff:ffff:ffff:ffff
118ff69:7500::/24ff69:75ff:ffff:ffff:ffff:ffff:ffff:ffff
119ff69:7600::/24ff69:76ff:ffff:ffff:ffff:ffff:ffff:ffff
120ff69:7700::/24ff69:77ff:ffff:ffff:ffff:ffff:ffff:ffff
121ff69:7800::/24ff69:78ff:ffff:ffff:ffff:ffff:ffff:ffff
122ff69:7900::/24ff69:79ff:ffff:ffff:ffff:ffff:ffff:ffff
123ff69:7a00::/24ff69:7aff:ffff:ffff:ffff:ffff:ffff:ffff
124ff69:7b00::/24ff69:7bff:ffff:ffff:ffff:ffff:ffff:ffff
125ff69:7c00::/24ff69:7cff:ffff:ffff:ffff:ffff:ffff:ffff
126ff69:7d00::/24ff69:7dff:ffff:ffff:ffff:ffff:ffff:ffff
127ff69:7e00::/24ff69:7eff:ffff:ffff:ffff:ffff:ffff:ffff
128ff69:7f00::/24ff69:7fff:ffff:ffff:ffff:ffff:ffff:ffff
129ff69:8000::/24ff69:80ff:ffff:ffff:ffff:ffff:ffff:ffff
130ff69:8100::/24ff69:81ff:ffff:ffff:ffff:ffff:ffff:ffff
131ff69:8200::/24ff69:82ff:ffff:ffff:ffff:ffff:ffff:ffff
132ff69:8300::/24ff69:83ff:ffff:ffff:ffff:ffff:ffff:ffff
133ff69:8400::/24ff69:84ff:ffff:ffff:ffff:ffff:ffff:ffff
134ff69:8500::/24ff69:85ff:ffff:ffff:ffff:ffff:ffff:ffff
135ff69:8600::/24ff69:86ff:ffff:ffff:ffff:ffff:ffff:ffff
136ff69:8700::/24ff69:87ff:ffff:ffff:ffff:ffff:ffff:ffff
137ff69:8800::/24ff69:88ff:ffff:ffff:ffff:ffff:ffff:ffff
138ff69:8900::/24ff69:89ff:ffff:ffff:ffff:ffff:ffff:ffff
139ff69:8a00::/24ff69:8aff:ffff:ffff:ffff:ffff:ffff:ffff
140ff69:8b00::/24ff69:8bff:ffff:ffff:ffff:ffff:ffff:ffff
141ff69:8c00::/24ff69:8cff:ffff:ffff:ffff:ffff:ffff:ffff
142ff69:8d00::/24ff69:8dff:ffff:ffff:ffff:ffff:ffff:ffff
143ff69:8e00::/24ff69:8eff:ffff:ffff:ffff:ffff:ffff:ffff
144ff69:8f00::/24ff69:8fff:ffff:ffff:ffff:ffff:ffff:ffff
145ff69:9000::/24ff69:90ff:ffff:ffff:ffff:ffff:ffff:ffff
146ff69:9100::/24ff69:91ff:ffff:ffff:ffff:ffff:ffff:ffff
147ff69:9200::/24ff69:92ff:ffff:ffff:ffff:ffff:ffff:ffff
148ff69:9300::/24ff69:93ff:ffff:ffff:ffff:ffff:ffff:ffff
149ff69:9400::/24ff69:94ff:ffff:ffff:ffff:ffff:ffff:ffff
150ff69:9500::/24ff69:95ff:ffff:ffff:ffff:ffff:ffff:ffff
151ff69:9600::/24ff69:96ff:ffff:ffff:ffff:ffff:ffff:ffff
152ff69:9700::/24ff69:97ff:ffff:ffff:ffff:ffff:ffff:ffff
153ff69:9800::/24ff69:98ff:ffff:ffff:ffff:ffff:ffff:ffff
154ff69:9900::/24ff69:99ff:ffff:ffff:ffff:ffff:ffff:ffff
155ff69:9a00::/24ff69:9aff:ffff:ffff:ffff:ffff:ffff:ffff
156ff69:9b00::/24ff69:9bff:ffff:ffff:ffff:ffff:ffff:ffff
157ff69:9c00::/24ff69:9cff:ffff:ffff:ffff:ffff:ffff:ffff
158ff69:9d00::/24ff69:9dff:ffff:ffff:ffff:ffff:ffff:ffff
159ff69:9e00::/24ff69:9eff:ffff:ffff:ffff:ffff:ffff:ffff
160ff69:9f00::/24ff69:9fff:ffff:ffff:ffff:ffff:ffff:ffff
161ff69:a000::/24ff69:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
162ff69:a100::/24ff69:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
163ff69:a200::/24ff69:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
164ff69:a300::/24ff69:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
165ff69:a400::/24ff69:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
166ff69:a500::/24ff69:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
167ff69:a600::/24ff69:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
168ff69:a700::/24ff69:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
169ff69:a800::/24ff69:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
170ff69:a900::/24ff69:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
171ff69:aa00::/24ff69:aaff:ffff:ffff:ffff:ffff:ffff:ffff
172ff69:ab00::/24ff69:abff:ffff:ffff:ffff:ffff:ffff:ffff
173ff69:ac00::/24ff69:acff:ffff:ffff:ffff:ffff:ffff:ffff
174ff69:ad00::/24ff69:adff:ffff:ffff:ffff:ffff:ffff:ffff
175ff69:ae00::/24ff69:aeff:ffff:ffff:ffff:ffff:ffff:ffff
176ff69:af00::/24ff69:afff:ffff:ffff:ffff:ffff:ffff:ffff
177ff69:b000::/24ff69:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
178ff69:b100::/24ff69:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
179ff69:b200::/24ff69:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
180ff69:b300::/24ff69:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
181ff69:b400::/24ff69:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
182ff69:b500::/24ff69:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
183ff69:b600::/24ff69:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
184ff69:b700::/24ff69:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
185ff69:b800::/24ff69:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
186ff69:b900::/24ff69:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
187ff69:ba00::/24ff69:baff:ffff:ffff:ffff:ffff:ffff:ffff
188ff69:bb00::/24ff69:bbff:ffff:ffff:ffff:ffff:ffff:ffff
189ff69:bc00::/24ff69:bcff:ffff:ffff:ffff:ffff:ffff:ffff
190ff69:bd00::/24ff69:bdff:ffff:ffff:ffff:ffff:ffff:ffff
191ff69:be00::/24ff69:beff:ffff:ffff:ffff:ffff:ffff:ffff
192ff69:bf00::/24ff69:bfff:ffff:ffff:ffff:ffff:ffff:ffff
193ff69:c000::/24ff69:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
194ff69:c100::/24ff69:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
195ff69:c200::/24ff69:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
196ff69:c300::/24ff69:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
197ff69:c400::/24ff69:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
198ff69:c500::/24ff69:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
199ff69:c600::/24ff69:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
200ff69:c700::/24ff69:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
201ff69:c800::/24ff69:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
202ff69:c900::/24ff69:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
203ff69:ca00::/24ff69:caff:ffff:ffff:ffff:ffff:ffff:ffff
204ff69:cb00::/24ff69:cbff:ffff:ffff:ffff:ffff:ffff:ffff
205ff69:cc00::/24ff69:ccff:ffff:ffff:ffff:ffff:ffff:ffff
206ff69:cd00::/24ff69:cdff:ffff:ffff:ffff:ffff:ffff:ffff
207ff69:ce00::/24ff69:ceff:ffff:ffff:ffff:ffff:ffff:ffff
208ff69:cf00::/24ff69:cfff:ffff:ffff:ffff:ffff:ffff:ffff
209ff69:d000::/24ff69:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
210ff69:d100::/24ff69:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
211ff69:d200::/24ff69:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
212ff69:d300::/24ff69:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
213ff69:d400::/24ff69:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
214ff69:d500::/24ff69:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
215ff69:d600::/24ff69:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
216ff69:d700::/24ff69:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
217ff69:d800::/24ff69:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
218ff69:d900::/24ff69:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
219ff69:da00::/24ff69:daff:ffff:ffff:ffff:ffff:ffff:ffff
220ff69:db00::/24ff69:dbff:ffff:ffff:ffff:ffff:ffff:ffff
221ff69:dc00::/24ff69:dcff:ffff:ffff:ffff:ffff:ffff:ffff
222ff69:dd00::/24ff69:ddff:ffff:ffff:ffff:ffff:ffff:ffff
223ff69:de00::/24ff69:deff:ffff:ffff:ffff:ffff:ffff:ffff
224ff69:df00::/24ff69:dfff:ffff:ffff:ffff:ffff:ffff:ffff
225ff69:e000::/24ff69:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
226ff69:e100::/24ff69:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
227ff69:e200::/24ff69:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
228ff69:e300::/24ff69:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
229ff69:e400::/24ff69:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
230ff69:e500::/24ff69:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
231ff69:e600::/24ff69:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
232ff69:e700::/24ff69:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
233ff69:e800::/24ff69:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
234ff69:e900::/24ff69:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
235ff69:ea00::/24ff69:eaff:ffff:ffff:ffff:ffff:ffff:ffff
236ff69:eb00::/24ff69:ebff:ffff:ffff:ffff:ffff:ffff:ffff
237ff69:ec00::/24ff69:ecff:ffff:ffff:ffff:ffff:ffff:ffff
238ff69:ed00::/24ff69:edff:ffff:ffff:ffff:ffff:ffff:ffff
239ff69:ee00::/24ff69:eeff:ffff:ffff:ffff:ffff:ffff:ffff
240ff69:ef00::/24ff69:efff:ffff:ffff:ffff:ffff:ffff:ffff
241ff69:f000::/24ff69:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
242ff69:f100::/24ff69:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
243ff69:f200::/24ff69:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
244ff69:f300::/24ff69:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
245ff69:f400::/24ff69:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
246ff69:f500::/24ff69:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
247ff69:f600::/24ff69:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
248ff69:f700::/24ff69:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
249ff69:f800::/24ff69:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
250ff69:f900::/24ff69:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
251ff69:fa00::/24ff69:faff:ffff:ffff:ffff:ffff:ffff:ffff
252ff69:fb00::/24ff69:fbff:ffff:ffff:ffff:ffff:ffff:ffff
253ff69:fc00::/24ff69:fcff:ffff:ffff:ffff:ffff:ffff:ffff
254ff69:fd00::/24ff69:fdff:ffff:ffff:ffff:ffff:ffff:ffff
255ff69:fe00::/24ff69:feff:ffff:ffff:ffff:ffff:ffff:ffff
256ff69:ff00::/24ff69: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.