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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
ff80::/16
First address
ff80::
Last address
ff80: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
ff80:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
0.8.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)

ff80::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
1ff80::/24ff80:ff:ffff:ffff:ffff:ffff:ffff:ffff
2ff80:100::/24ff80:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3ff80:200::/24ff80:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4ff80:300::/24ff80:3ff:ffff:ffff:ffff:ffff:ffff:ffff
5ff80:400::/24ff80:4ff:ffff:ffff:ffff:ffff:ffff:ffff
6ff80:500::/24ff80:5ff:ffff:ffff:ffff:ffff:ffff:ffff
7ff80:600::/24ff80:6ff:ffff:ffff:ffff:ffff:ffff:ffff
8ff80:700::/24ff80:7ff:ffff:ffff:ffff:ffff:ffff:ffff
9ff80:800::/24ff80:8ff:ffff:ffff:ffff:ffff:ffff:ffff
10ff80:900::/24ff80:9ff:ffff:ffff:ffff:ffff:ffff:ffff
11ff80:a00::/24ff80:aff:ffff:ffff:ffff:ffff:ffff:ffff
12ff80:b00::/24ff80:bff:ffff:ffff:ffff:ffff:ffff:ffff
13ff80:c00::/24ff80:cff:ffff:ffff:ffff:ffff:ffff:ffff
14ff80:d00::/24ff80:dff:ffff:ffff:ffff:ffff:ffff:ffff
15ff80:e00::/24ff80:eff:ffff:ffff:ffff:ffff:ffff:ffff
16ff80:f00::/24ff80:fff:ffff:ffff:ffff:ffff:ffff:ffff
17ff80:1000::/24ff80:10ff:ffff:ffff:ffff:ffff:ffff:ffff
18ff80:1100::/24ff80:11ff:ffff:ffff:ffff:ffff:ffff:ffff
19ff80:1200::/24ff80:12ff:ffff:ffff:ffff:ffff:ffff:ffff
20ff80:1300::/24ff80:13ff:ffff:ffff:ffff:ffff:ffff:ffff
21ff80:1400::/24ff80:14ff:ffff:ffff:ffff:ffff:ffff:ffff
22ff80:1500::/24ff80:15ff:ffff:ffff:ffff:ffff:ffff:ffff
23ff80:1600::/24ff80:16ff:ffff:ffff:ffff:ffff:ffff:ffff
24ff80:1700::/24ff80:17ff:ffff:ffff:ffff:ffff:ffff:ffff
25ff80:1800::/24ff80:18ff:ffff:ffff:ffff:ffff:ffff:ffff
26ff80:1900::/24ff80:19ff:ffff:ffff:ffff:ffff:ffff:ffff
27ff80:1a00::/24ff80:1aff:ffff:ffff:ffff:ffff:ffff:ffff
28ff80:1b00::/24ff80:1bff:ffff:ffff:ffff:ffff:ffff:ffff
29ff80:1c00::/24ff80:1cff:ffff:ffff:ffff:ffff:ffff:ffff
30ff80:1d00::/24ff80:1dff:ffff:ffff:ffff:ffff:ffff:ffff
31ff80:1e00::/24ff80:1eff:ffff:ffff:ffff:ffff:ffff:ffff
32ff80:1f00::/24ff80:1fff:ffff:ffff:ffff:ffff:ffff:ffff
33ff80:2000::/24ff80:20ff:ffff:ffff:ffff:ffff:ffff:ffff
34ff80:2100::/24ff80:21ff:ffff:ffff:ffff:ffff:ffff:ffff
35ff80:2200::/24ff80:22ff:ffff:ffff:ffff:ffff:ffff:ffff
36ff80:2300::/24ff80:23ff:ffff:ffff:ffff:ffff:ffff:ffff
37ff80:2400::/24ff80:24ff:ffff:ffff:ffff:ffff:ffff:ffff
38ff80:2500::/24ff80:25ff:ffff:ffff:ffff:ffff:ffff:ffff
39ff80:2600::/24ff80:26ff:ffff:ffff:ffff:ffff:ffff:ffff
40ff80:2700::/24ff80:27ff:ffff:ffff:ffff:ffff:ffff:ffff
41ff80:2800::/24ff80:28ff:ffff:ffff:ffff:ffff:ffff:ffff
42ff80:2900::/24ff80:29ff:ffff:ffff:ffff:ffff:ffff:ffff
43ff80:2a00::/24ff80:2aff:ffff:ffff:ffff:ffff:ffff:ffff
44ff80:2b00::/24ff80:2bff:ffff:ffff:ffff:ffff:ffff:ffff
45ff80:2c00::/24ff80:2cff:ffff:ffff:ffff:ffff:ffff:ffff
46ff80:2d00::/24ff80:2dff:ffff:ffff:ffff:ffff:ffff:ffff
47ff80:2e00::/24ff80:2eff:ffff:ffff:ffff:ffff:ffff:ffff
48ff80:2f00::/24ff80:2fff:ffff:ffff:ffff:ffff:ffff:ffff
49ff80:3000::/24ff80:30ff:ffff:ffff:ffff:ffff:ffff:ffff
50ff80:3100::/24ff80:31ff:ffff:ffff:ffff:ffff:ffff:ffff
51ff80:3200::/24ff80:32ff:ffff:ffff:ffff:ffff:ffff:ffff
52ff80:3300::/24ff80:33ff:ffff:ffff:ffff:ffff:ffff:ffff
53ff80:3400::/24ff80:34ff:ffff:ffff:ffff:ffff:ffff:ffff
54ff80:3500::/24ff80:35ff:ffff:ffff:ffff:ffff:ffff:ffff
55ff80:3600::/24ff80:36ff:ffff:ffff:ffff:ffff:ffff:ffff
56ff80:3700::/24ff80:37ff:ffff:ffff:ffff:ffff:ffff:ffff
57ff80:3800::/24ff80:38ff:ffff:ffff:ffff:ffff:ffff:ffff
58ff80:3900::/24ff80:39ff:ffff:ffff:ffff:ffff:ffff:ffff
59ff80:3a00::/24ff80:3aff:ffff:ffff:ffff:ffff:ffff:ffff
60ff80:3b00::/24ff80:3bff:ffff:ffff:ffff:ffff:ffff:ffff
61ff80:3c00::/24ff80:3cff:ffff:ffff:ffff:ffff:ffff:ffff
62ff80:3d00::/24ff80:3dff:ffff:ffff:ffff:ffff:ffff:ffff
63ff80:3e00::/24ff80:3eff:ffff:ffff:ffff:ffff:ffff:ffff
64ff80:3f00::/24ff80:3fff:ffff:ffff:ffff:ffff:ffff:ffff
65ff80:4000::/24ff80:40ff:ffff:ffff:ffff:ffff:ffff:ffff
66ff80:4100::/24ff80:41ff:ffff:ffff:ffff:ffff:ffff:ffff
67ff80:4200::/24ff80:42ff:ffff:ffff:ffff:ffff:ffff:ffff
68ff80:4300::/24ff80:43ff:ffff:ffff:ffff:ffff:ffff:ffff
69ff80:4400::/24ff80:44ff:ffff:ffff:ffff:ffff:ffff:ffff
70ff80:4500::/24ff80:45ff:ffff:ffff:ffff:ffff:ffff:ffff
71ff80:4600::/24ff80:46ff:ffff:ffff:ffff:ffff:ffff:ffff
72ff80:4700::/24ff80:47ff:ffff:ffff:ffff:ffff:ffff:ffff
73ff80:4800::/24ff80:48ff:ffff:ffff:ffff:ffff:ffff:ffff
74ff80:4900::/24ff80:49ff:ffff:ffff:ffff:ffff:ffff:ffff
75ff80:4a00::/24ff80:4aff:ffff:ffff:ffff:ffff:ffff:ffff
76ff80:4b00::/24ff80:4bff:ffff:ffff:ffff:ffff:ffff:ffff
77ff80:4c00::/24ff80:4cff:ffff:ffff:ffff:ffff:ffff:ffff
78ff80:4d00::/24ff80:4dff:ffff:ffff:ffff:ffff:ffff:ffff
79ff80:4e00::/24ff80:4eff:ffff:ffff:ffff:ffff:ffff:ffff
80ff80:4f00::/24ff80:4fff:ffff:ffff:ffff:ffff:ffff:ffff
81ff80:5000::/24ff80:50ff:ffff:ffff:ffff:ffff:ffff:ffff
82ff80:5100::/24ff80:51ff:ffff:ffff:ffff:ffff:ffff:ffff
83ff80:5200::/24ff80:52ff:ffff:ffff:ffff:ffff:ffff:ffff
84ff80:5300::/24ff80:53ff:ffff:ffff:ffff:ffff:ffff:ffff
85ff80:5400::/24ff80:54ff:ffff:ffff:ffff:ffff:ffff:ffff
86ff80:5500::/24ff80:55ff:ffff:ffff:ffff:ffff:ffff:ffff
87ff80:5600::/24ff80:56ff:ffff:ffff:ffff:ffff:ffff:ffff
88ff80:5700::/24ff80:57ff:ffff:ffff:ffff:ffff:ffff:ffff
89ff80:5800::/24ff80:58ff:ffff:ffff:ffff:ffff:ffff:ffff
90ff80:5900::/24ff80:59ff:ffff:ffff:ffff:ffff:ffff:ffff
91ff80:5a00::/24ff80:5aff:ffff:ffff:ffff:ffff:ffff:ffff
92ff80:5b00::/24ff80:5bff:ffff:ffff:ffff:ffff:ffff:ffff
93ff80:5c00::/24ff80:5cff:ffff:ffff:ffff:ffff:ffff:ffff
94ff80:5d00::/24ff80:5dff:ffff:ffff:ffff:ffff:ffff:ffff
95ff80:5e00::/24ff80:5eff:ffff:ffff:ffff:ffff:ffff:ffff
96ff80:5f00::/24ff80:5fff:ffff:ffff:ffff:ffff:ffff:ffff
97ff80:6000::/24ff80:60ff:ffff:ffff:ffff:ffff:ffff:ffff
98ff80:6100::/24ff80:61ff:ffff:ffff:ffff:ffff:ffff:ffff
99ff80:6200::/24ff80:62ff:ffff:ffff:ffff:ffff:ffff:ffff
100ff80:6300::/24ff80:63ff:ffff:ffff:ffff:ffff:ffff:ffff
101ff80:6400::/24ff80:64ff:ffff:ffff:ffff:ffff:ffff:ffff
102ff80:6500::/24ff80:65ff:ffff:ffff:ffff:ffff:ffff:ffff
103ff80:6600::/24ff80:66ff:ffff:ffff:ffff:ffff:ffff:ffff
104ff80:6700::/24ff80:67ff:ffff:ffff:ffff:ffff:ffff:ffff
105ff80:6800::/24ff80:68ff:ffff:ffff:ffff:ffff:ffff:ffff
106ff80:6900::/24ff80:69ff:ffff:ffff:ffff:ffff:ffff:ffff
107ff80:6a00::/24ff80:6aff:ffff:ffff:ffff:ffff:ffff:ffff
108ff80:6b00::/24ff80:6bff:ffff:ffff:ffff:ffff:ffff:ffff
109ff80:6c00::/24ff80:6cff:ffff:ffff:ffff:ffff:ffff:ffff
110ff80:6d00::/24ff80:6dff:ffff:ffff:ffff:ffff:ffff:ffff
111ff80:6e00::/24ff80:6eff:ffff:ffff:ffff:ffff:ffff:ffff
112ff80:6f00::/24ff80:6fff:ffff:ffff:ffff:ffff:ffff:ffff
113ff80:7000::/24ff80:70ff:ffff:ffff:ffff:ffff:ffff:ffff
114ff80:7100::/24ff80:71ff:ffff:ffff:ffff:ffff:ffff:ffff
115ff80:7200::/24ff80:72ff:ffff:ffff:ffff:ffff:ffff:ffff
116ff80:7300::/24ff80:73ff:ffff:ffff:ffff:ffff:ffff:ffff
117ff80:7400::/24ff80:74ff:ffff:ffff:ffff:ffff:ffff:ffff
118ff80:7500::/24ff80:75ff:ffff:ffff:ffff:ffff:ffff:ffff
119ff80:7600::/24ff80:76ff:ffff:ffff:ffff:ffff:ffff:ffff
120ff80:7700::/24ff80:77ff:ffff:ffff:ffff:ffff:ffff:ffff
121ff80:7800::/24ff80:78ff:ffff:ffff:ffff:ffff:ffff:ffff
122ff80:7900::/24ff80:79ff:ffff:ffff:ffff:ffff:ffff:ffff
123ff80:7a00::/24ff80:7aff:ffff:ffff:ffff:ffff:ffff:ffff
124ff80:7b00::/24ff80:7bff:ffff:ffff:ffff:ffff:ffff:ffff
125ff80:7c00::/24ff80:7cff:ffff:ffff:ffff:ffff:ffff:ffff
126ff80:7d00::/24ff80:7dff:ffff:ffff:ffff:ffff:ffff:ffff
127ff80:7e00::/24ff80:7eff:ffff:ffff:ffff:ffff:ffff:ffff
128ff80:7f00::/24ff80:7fff:ffff:ffff:ffff:ffff:ffff:ffff
129ff80:8000::/24ff80:80ff:ffff:ffff:ffff:ffff:ffff:ffff
130ff80:8100::/24ff80:81ff:ffff:ffff:ffff:ffff:ffff:ffff
131ff80:8200::/24ff80:82ff:ffff:ffff:ffff:ffff:ffff:ffff
132ff80:8300::/24ff80:83ff:ffff:ffff:ffff:ffff:ffff:ffff
133ff80:8400::/24ff80:84ff:ffff:ffff:ffff:ffff:ffff:ffff
134ff80:8500::/24ff80:85ff:ffff:ffff:ffff:ffff:ffff:ffff
135ff80:8600::/24ff80:86ff:ffff:ffff:ffff:ffff:ffff:ffff
136ff80:8700::/24ff80:87ff:ffff:ffff:ffff:ffff:ffff:ffff
137ff80:8800::/24ff80:88ff:ffff:ffff:ffff:ffff:ffff:ffff
138ff80:8900::/24ff80:89ff:ffff:ffff:ffff:ffff:ffff:ffff
139ff80:8a00::/24ff80:8aff:ffff:ffff:ffff:ffff:ffff:ffff
140ff80:8b00::/24ff80:8bff:ffff:ffff:ffff:ffff:ffff:ffff
141ff80:8c00::/24ff80:8cff:ffff:ffff:ffff:ffff:ffff:ffff
142ff80:8d00::/24ff80:8dff:ffff:ffff:ffff:ffff:ffff:ffff
143ff80:8e00::/24ff80:8eff:ffff:ffff:ffff:ffff:ffff:ffff
144ff80:8f00::/24ff80:8fff:ffff:ffff:ffff:ffff:ffff:ffff
145ff80:9000::/24ff80:90ff:ffff:ffff:ffff:ffff:ffff:ffff
146ff80:9100::/24ff80:91ff:ffff:ffff:ffff:ffff:ffff:ffff
147ff80:9200::/24ff80:92ff:ffff:ffff:ffff:ffff:ffff:ffff
148ff80:9300::/24ff80:93ff:ffff:ffff:ffff:ffff:ffff:ffff
149ff80:9400::/24ff80:94ff:ffff:ffff:ffff:ffff:ffff:ffff
150ff80:9500::/24ff80:95ff:ffff:ffff:ffff:ffff:ffff:ffff
151ff80:9600::/24ff80:96ff:ffff:ffff:ffff:ffff:ffff:ffff
152ff80:9700::/24ff80:97ff:ffff:ffff:ffff:ffff:ffff:ffff
153ff80:9800::/24ff80:98ff:ffff:ffff:ffff:ffff:ffff:ffff
154ff80:9900::/24ff80:99ff:ffff:ffff:ffff:ffff:ffff:ffff
155ff80:9a00::/24ff80:9aff:ffff:ffff:ffff:ffff:ffff:ffff
156ff80:9b00::/24ff80:9bff:ffff:ffff:ffff:ffff:ffff:ffff
157ff80:9c00::/24ff80:9cff:ffff:ffff:ffff:ffff:ffff:ffff
158ff80:9d00::/24ff80:9dff:ffff:ffff:ffff:ffff:ffff:ffff
159ff80:9e00::/24ff80:9eff:ffff:ffff:ffff:ffff:ffff:ffff
160ff80:9f00::/24ff80:9fff:ffff:ffff:ffff:ffff:ffff:ffff
161ff80:a000::/24ff80:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
162ff80:a100::/24ff80:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
163ff80:a200::/24ff80:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
164ff80:a300::/24ff80:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
165ff80:a400::/24ff80:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
166ff80:a500::/24ff80:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
167ff80:a600::/24ff80:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
168ff80:a700::/24ff80:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
169ff80:a800::/24ff80:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
170ff80:a900::/24ff80:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
171ff80:aa00::/24ff80:aaff:ffff:ffff:ffff:ffff:ffff:ffff
172ff80:ab00::/24ff80:abff:ffff:ffff:ffff:ffff:ffff:ffff
173ff80:ac00::/24ff80:acff:ffff:ffff:ffff:ffff:ffff:ffff
174ff80:ad00::/24ff80:adff:ffff:ffff:ffff:ffff:ffff:ffff
175ff80:ae00::/24ff80:aeff:ffff:ffff:ffff:ffff:ffff:ffff
176ff80:af00::/24ff80:afff:ffff:ffff:ffff:ffff:ffff:ffff
177ff80:b000::/24ff80:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
178ff80:b100::/24ff80:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
179ff80:b200::/24ff80:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
180ff80:b300::/24ff80:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
181ff80:b400::/24ff80:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
182ff80:b500::/24ff80:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
183ff80:b600::/24ff80:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
184ff80:b700::/24ff80:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
185ff80:b800::/24ff80:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
186ff80:b900::/24ff80:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
187ff80:ba00::/24ff80:baff:ffff:ffff:ffff:ffff:ffff:ffff
188ff80:bb00::/24ff80:bbff:ffff:ffff:ffff:ffff:ffff:ffff
189ff80:bc00::/24ff80:bcff:ffff:ffff:ffff:ffff:ffff:ffff
190ff80:bd00::/24ff80:bdff:ffff:ffff:ffff:ffff:ffff:ffff
191ff80:be00::/24ff80:beff:ffff:ffff:ffff:ffff:ffff:ffff
192ff80:bf00::/24ff80:bfff:ffff:ffff:ffff:ffff:ffff:ffff
193ff80:c000::/24ff80:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
194ff80:c100::/24ff80:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
195ff80:c200::/24ff80:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
196ff80:c300::/24ff80:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
197ff80:c400::/24ff80:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
198ff80:c500::/24ff80:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
199ff80:c600::/24ff80:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
200ff80:c700::/24ff80:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
201ff80:c800::/24ff80:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
202ff80:c900::/24ff80:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
203ff80:ca00::/24ff80:caff:ffff:ffff:ffff:ffff:ffff:ffff
204ff80:cb00::/24ff80:cbff:ffff:ffff:ffff:ffff:ffff:ffff
205ff80:cc00::/24ff80:ccff:ffff:ffff:ffff:ffff:ffff:ffff
206ff80:cd00::/24ff80:cdff:ffff:ffff:ffff:ffff:ffff:ffff
207ff80:ce00::/24ff80:ceff:ffff:ffff:ffff:ffff:ffff:ffff
208ff80:cf00::/24ff80:cfff:ffff:ffff:ffff:ffff:ffff:ffff
209ff80:d000::/24ff80:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
210ff80:d100::/24ff80:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
211ff80:d200::/24ff80:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
212ff80:d300::/24ff80:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
213ff80:d400::/24ff80:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
214ff80:d500::/24ff80:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
215ff80:d600::/24ff80:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
216ff80:d700::/24ff80:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
217ff80:d800::/24ff80:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
218ff80:d900::/24ff80:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
219ff80:da00::/24ff80:daff:ffff:ffff:ffff:ffff:ffff:ffff
220ff80:db00::/24ff80:dbff:ffff:ffff:ffff:ffff:ffff:ffff
221ff80:dc00::/24ff80:dcff:ffff:ffff:ffff:ffff:ffff:ffff
222ff80:dd00::/24ff80:ddff:ffff:ffff:ffff:ffff:ffff:ffff
223ff80:de00::/24ff80:deff:ffff:ffff:ffff:ffff:ffff:ffff
224ff80:df00::/24ff80:dfff:ffff:ffff:ffff:ffff:ffff:ffff
225ff80:e000::/24ff80:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
226ff80:e100::/24ff80:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
227ff80:e200::/24ff80:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
228ff80:e300::/24ff80:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
229ff80:e400::/24ff80:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
230ff80:e500::/24ff80:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
231ff80:e600::/24ff80:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
232ff80:e700::/24ff80:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
233ff80:e800::/24ff80:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
234ff80:e900::/24ff80:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
235ff80:ea00::/24ff80:eaff:ffff:ffff:ffff:ffff:ffff:ffff
236ff80:eb00::/24ff80:ebff:ffff:ffff:ffff:ffff:ffff:ffff
237ff80:ec00::/24ff80:ecff:ffff:ffff:ffff:ffff:ffff:ffff
238ff80:ed00::/24ff80:edff:ffff:ffff:ffff:ffff:ffff:ffff
239ff80:ee00::/24ff80:eeff:ffff:ffff:ffff:ffff:ffff:ffff
240ff80:ef00::/24ff80:efff:ffff:ffff:ffff:ffff:ffff:ffff
241ff80:f000::/24ff80:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
242ff80:f100::/24ff80:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
243ff80:f200::/24ff80:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
244ff80:f300::/24ff80:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
245ff80:f400::/24ff80:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
246ff80:f500::/24ff80:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
247ff80:f600::/24ff80:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
248ff80:f700::/24ff80:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
249ff80:f800::/24ff80:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
250ff80:f900::/24ff80:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
251ff80:fa00::/24ff80:faff:ffff:ffff:ffff:ffff:ffff:ffff
252ff80:fb00::/24ff80:fbff:ffff:ffff:ffff:ffff:ffff:ffff
253ff80:fc00::/24ff80:fcff:ffff:ffff:ffff:ffff:ffff:ffff
254ff80:fd00::/24ff80:fdff:ffff:ffff:ffff:ffff:ffff:ffff
255ff80:fe00::/24ff80:feff:ffff:ffff:ffff:ffff:ffff:ffff
256ff80:ff00::/24ff80: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.