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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
ff93::/16
First address
ff93::
Last address
ff93: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
ff93:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
3.9.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)

ff93::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
1ff93::/24ff93:ff:ffff:ffff:ffff:ffff:ffff:ffff
2ff93:100::/24ff93:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3ff93:200::/24ff93:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4ff93:300::/24ff93:3ff:ffff:ffff:ffff:ffff:ffff:ffff
5ff93:400::/24ff93:4ff:ffff:ffff:ffff:ffff:ffff:ffff
6ff93:500::/24ff93:5ff:ffff:ffff:ffff:ffff:ffff:ffff
7ff93:600::/24ff93:6ff:ffff:ffff:ffff:ffff:ffff:ffff
8ff93:700::/24ff93:7ff:ffff:ffff:ffff:ffff:ffff:ffff
9ff93:800::/24ff93:8ff:ffff:ffff:ffff:ffff:ffff:ffff
10ff93:900::/24ff93:9ff:ffff:ffff:ffff:ffff:ffff:ffff
11ff93:a00::/24ff93:aff:ffff:ffff:ffff:ffff:ffff:ffff
12ff93:b00::/24ff93:bff:ffff:ffff:ffff:ffff:ffff:ffff
13ff93:c00::/24ff93:cff:ffff:ffff:ffff:ffff:ffff:ffff
14ff93:d00::/24ff93:dff:ffff:ffff:ffff:ffff:ffff:ffff
15ff93:e00::/24ff93:eff:ffff:ffff:ffff:ffff:ffff:ffff
16ff93:f00::/24ff93:fff:ffff:ffff:ffff:ffff:ffff:ffff
17ff93:1000::/24ff93:10ff:ffff:ffff:ffff:ffff:ffff:ffff
18ff93:1100::/24ff93:11ff:ffff:ffff:ffff:ffff:ffff:ffff
19ff93:1200::/24ff93:12ff:ffff:ffff:ffff:ffff:ffff:ffff
20ff93:1300::/24ff93:13ff:ffff:ffff:ffff:ffff:ffff:ffff
21ff93:1400::/24ff93:14ff:ffff:ffff:ffff:ffff:ffff:ffff
22ff93:1500::/24ff93:15ff:ffff:ffff:ffff:ffff:ffff:ffff
23ff93:1600::/24ff93:16ff:ffff:ffff:ffff:ffff:ffff:ffff
24ff93:1700::/24ff93:17ff:ffff:ffff:ffff:ffff:ffff:ffff
25ff93:1800::/24ff93:18ff:ffff:ffff:ffff:ffff:ffff:ffff
26ff93:1900::/24ff93:19ff:ffff:ffff:ffff:ffff:ffff:ffff
27ff93:1a00::/24ff93:1aff:ffff:ffff:ffff:ffff:ffff:ffff
28ff93:1b00::/24ff93:1bff:ffff:ffff:ffff:ffff:ffff:ffff
29ff93:1c00::/24ff93:1cff:ffff:ffff:ffff:ffff:ffff:ffff
30ff93:1d00::/24ff93:1dff:ffff:ffff:ffff:ffff:ffff:ffff
31ff93:1e00::/24ff93:1eff:ffff:ffff:ffff:ffff:ffff:ffff
32ff93:1f00::/24ff93:1fff:ffff:ffff:ffff:ffff:ffff:ffff
33ff93:2000::/24ff93:20ff:ffff:ffff:ffff:ffff:ffff:ffff
34ff93:2100::/24ff93:21ff:ffff:ffff:ffff:ffff:ffff:ffff
35ff93:2200::/24ff93:22ff:ffff:ffff:ffff:ffff:ffff:ffff
36ff93:2300::/24ff93:23ff:ffff:ffff:ffff:ffff:ffff:ffff
37ff93:2400::/24ff93:24ff:ffff:ffff:ffff:ffff:ffff:ffff
38ff93:2500::/24ff93:25ff:ffff:ffff:ffff:ffff:ffff:ffff
39ff93:2600::/24ff93:26ff:ffff:ffff:ffff:ffff:ffff:ffff
40ff93:2700::/24ff93:27ff:ffff:ffff:ffff:ffff:ffff:ffff
41ff93:2800::/24ff93:28ff:ffff:ffff:ffff:ffff:ffff:ffff
42ff93:2900::/24ff93:29ff:ffff:ffff:ffff:ffff:ffff:ffff
43ff93:2a00::/24ff93:2aff:ffff:ffff:ffff:ffff:ffff:ffff
44ff93:2b00::/24ff93:2bff:ffff:ffff:ffff:ffff:ffff:ffff
45ff93:2c00::/24ff93:2cff:ffff:ffff:ffff:ffff:ffff:ffff
46ff93:2d00::/24ff93:2dff:ffff:ffff:ffff:ffff:ffff:ffff
47ff93:2e00::/24ff93:2eff:ffff:ffff:ffff:ffff:ffff:ffff
48ff93:2f00::/24ff93:2fff:ffff:ffff:ffff:ffff:ffff:ffff
49ff93:3000::/24ff93:30ff:ffff:ffff:ffff:ffff:ffff:ffff
50ff93:3100::/24ff93:31ff:ffff:ffff:ffff:ffff:ffff:ffff
51ff93:3200::/24ff93:32ff:ffff:ffff:ffff:ffff:ffff:ffff
52ff93:3300::/24ff93:33ff:ffff:ffff:ffff:ffff:ffff:ffff
53ff93:3400::/24ff93:34ff:ffff:ffff:ffff:ffff:ffff:ffff
54ff93:3500::/24ff93:35ff:ffff:ffff:ffff:ffff:ffff:ffff
55ff93:3600::/24ff93:36ff:ffff:ffff:ffff:ffff:ffff:ffff
56ff93:3700::/24ff93:37ff:ffff:ffff:ffff:ffff:ffff:ffff
57ff93:3800::/24ff93:38ff:ffff:ffff:ffff:ffff:ffff:ffff
58ff93:3900::/24ff93:39ff:ffff:ffff:ffff:ffff:ffff:ffff
59ff93:3a00::/24ff93:3aff:ffff:ffff:ffff:ffff:ffff:ffff
60ff93:3b00::/24ff93:3bff:ffff:ffff:ffff:ffff:ffff:ffff
61ff93:3c00::/24ff93:3cff:ffff:ffff:ffff:ffff:ffff:ffff
62ff93:3d00::/24ff93:3dff:ffff:ffff:ffff:ffff:ffff:ffff
63ff93:3e00::/24ff93:3eff:ffff:ffff:ffff:ffff:ffff:ffff
64ff93:3f00::/24ff93:3fff:ffff:ffff:ffff:ffff:ffff:ffff
65ff93:4000::/24ff93:40ff:ffff:ffff:ffff:ffff:ffff:ffff
66ff93:4100::/24ff93:41ff:ffff:ffff:ffff:ffff:ffff:ffff
67ff93:4200::/24ff93:42ff:ffff:ffff:ffff:ffff:ffff:ffff
68ff93:4300::/24ff93:43ff:ffff:ffff:ffff:ffff:ffff:ffff
69ff93:4400::/24ff93:44ff:ffff:ffff:ffff:ffff:ffff:ffff
70ff93:4500::/24ff93:45ff:ffff:ffff:ffff:ffff:ffff:ffff
71ff93:4600::/24ff93:46ff:ffff:ffff:ffff:ffff:ffff:ffff
72ff93:4700::/24ff93:47ff:ffff:ffff:ffff:ffff:ffff:ffff
73ff93:4800::/24ff93:48ff:ffff:ffff:ffff:ffff:ffff:ffff
74ff93:4900::/24ff93:49ff:ffff:ffff:ffff:ffff:ffff:ffff
75ff93:4a00::/24ff93:4aff:ffff:ffff:ffff:ffff:ffff:ffff
76ff93:4b00::/24ff93:4bff:ffff:ffff:ffff:ffff:ffff:ffff
77ff93:4c00::/24ff93:4cff:ffff:ffff:ffff:ffff:ffff:ffff
78ff93:4d00::/24ff93:4dff:ffff:ffff:ffff:ffff:ffff:ffff
79ff93:4e00::/24ff93:4eff:ffff:ffff:ffff:ffff:ffff:ffff
80ff93:4f00::/24ff93:4fff:ffff:ffff:ffff:ffff:ffff:ffff
81ff93:5000::/24ff93:50ff:ffff:ffff:ffff:ffff:ffff:ffff
82ff93:5100::/24ff93:51ff:ffff:ffff:ffff:ffff:ffff:ffff
83ff93:5200::/24ff93:52ff:ffff:ffff:ffff:ffff:ffff:ffff
84ff93:5300::/24ff93:53ff:ffff:ffff:ffff:ffff:ffff:ffff
85ff93:5400::/24ff93:54ff:ffff:ffff:ffff:ffff:ffff:ffff
86ff93:5500::/24ff93:55ff:ffff:ffff:ffff:ffff:ffff:ffff
87ff93:5600::/24ff93:56ff:ffff:ffff:ffff:ffff:ffff:ffff
88ff93:5700::/24ff93:57ff:ffff:ffff:ffff:ffff:ffff:ffff
89ff93:5800::/24ff93:58ff:ffff:ffff:ffff:ffff:ffff:ffff
90ff93:5900::/24ff93:59ff:ffff:ffff:ffff:ffff:ffff:ffff
91ff93:5a00::/24ff93:5aff:ffff:ffff:ffff:ffff:ffff:ffff
92ff93:5b00::/24ff93:5bff:ffff:ffff:ffff:ffff:ffff:ffff
93ff93:5c00::/24ff93:5cff:ffff:ffff:ffff:ffff:ffff:ffff
94ff93:5d00::/24ff93:5dff:ffff:ffff:ffff:ffff:ffff:ffff
95ff93:5e00::/24ff93:5eff:ffff:ffff:ffff:ffff:ffff:ffff
96ff93:5f00::/24ff93:5fff:ffff:ffff:ffff:ffff:ffff:ffff
97ff93:6000::/24ff93:60ff:ffff:ffff:ffff:ffff:ffff:ffff
98ff93:6100::/24ff93:61ff:ffff:ffff:ffff:ffff:ffff:ffff
99ff93:6200::/24ff93:62ff:ffff:ffff:ffff:ffff:ffff:ffff
100ff93:6300::/24ff93:63ff:ffff:ffff:ffff:ffff:ffff:ffff
101ff93:6400::/24ff93:64ff:ffff:ffff:ffff:ffff:ffff:ffff
102ff93:6500::/24ff93:65ff:ffff:ffff:ffff:ffff:ffff:ffff
103ff93:6600::/24ff93:66ff:ffff:ffff:ffff:ffff:ffff:ffff
104ff93:6700::/24ff93:67ff:ffff:ffff:ffff:ffff:ffff:ffff
105ff93:6800::/24ff93:68ff:ffff:ffff:ffff:ffff:ffff:ffff
106ff93:6900::/24ff93:69ff:ffff:ffff:ffff:ffff:ffff:ffff
107ff93:6a00::/24ff93:6aff:ffff:ffff:ffff:ffff:ffff:ffff
108ff93:6b00::/24ff93:6bff:ffff:ffff:ffff:ffff:ffff:ffff
109ff93:6c00::/24ff93:6cff:ffff:ffff:ffff:ffff:ffff:ffff
110ff93:6d00::/24ff93:6dff:ffff:ffff:ffff:ffff:ffff:ffff
111ff93:6e00::/24ff93:6eff:ffff:ffff:ffff:ffff:ffff:ffff
112ff93:6f00::/24ff93:6fff:ffff:ffff:ffff:ffff:ffff:ffff
113ff93:7000::/24ff93:70ff:ffff:ffff:ffff:ffff:ffff:ffff
114ff93:7100::/24ff93:71ff:ffff:ffff:ffff:ffff:ffff:ffff
115ff93:7200::/24ff93:72ff:ffff:ffff:ffff:ffff:ffff:ffff
116ff93:7300::/24ff93:73ff:ffff:ffff:ffff:ffff:ffff:ffff
117ff93:7400::/24ff93:74ff:ffff:ffff:ffff:ffff:ffff:ffff
118ff93:7500::/24ff93:75ff:ffff:ffff:ffff:ffff:ffff:ffff
119ff93:7600::/24ff93:76ff:ffff:ffff:ffff:ffff:ffff:ffff
120ff93:7700::/24ff93:77ff:ffff:ffff:ffff:ffff:ffff:ffff
121ff93:7800::/24ff93:78ff:ffff:ffff:ffff:ffff:ffff:ffff
122ff93:7900::/24ff93:79ff:ffff:ffff:ffff:ffff:ffff:ffff
123ff93:7a00::/24ff93:7aff:ffff:ffff:ffff:ffff:ffff:ffff
124ff93:7b00::/24ff93:7bff:ffff:ffff:ffff:ffff:ffff:ffff
125ff93:7c00::/24ff93:7cff:ffff:ffff:ffff:ffff:ffff:ffff
126ff93:7d00::/24ff93:7dff:ffff:ffff:ffff:ffff:ffff:ffff
127ff93:7e00::/24ff93:7eff:ffff:ffff:ffff:ffff:ffff:ffff
128ff93:7f00::/24ff93:7fff:ffff:ffff:ffff:ffff:ffff:ffff
129ff93:8000::/24ff93:80ff:ffff:ffff:ffff:ffff:ffff:ffff
130ff93:8100::/24ff93:81ff:ffff:ffff:ffff:ffff:ffff:ffff
131ff93:8200::/24ff93:82ff:ffff:ffff:ffff:ffff:ffff:ffff
132ff93:8300::/24ff93:83ff:ffff:ffff:ffff:ffff:ffff:ffff
133ff93:8400::/24ff93:84ff:ffff:ffff:ffff:ffff:ffff:ffff
134ff93:8500::/24ff93:85ff:ffff:ffff:ffff:ffff:ffff:ffff
135ff93:8600::/24ff93:86ff:ffff:ffff:ffff:ffff:ffff:ffff
136ff93:8700::/24ff93:87ff:ffff:ffff:ffff:ffff:ffff:ffff
137ff93:8800::/24ff93:88ff:ffff:ffff:ffff:ffff:ffff:ffff
138ff93:8900::/24ff93:89ff:ffff:ffff:ffff:ffff:ffff:ffff
139ff93:8a00::/24ff93:8aff:ffff:ffff:ffff:ffff:ffff:ffff
140ff93:8b00::/24ff93:8bff:ffff:ffff:ffff:ffff:ffff:ffff
141ff93:8c00::/24ff93:8cff:ffff:ffff:ffff:ffff:ffff:ffff
142ff93:8d00::/24ff93:8dff:ffff:ffff:ffff:ffff:ffff:ffff
143ff93:8e00::/24ff93:8eff:ffff:ffff:ffff:ffff:ffff:ffff
144ff93:8f00::/24ff93:8fff:ffff:ffff:ffff:ffff:ffff:ffff
145ff93:9000::/24ff93:90ff:ffff:ffff:ffff:ffff:ffff:ffff
146ff93:9100::/24ff93:91ff:ffff:ffff:ffff:ffff:ffff:ffff
147ff93:9200::/24ff93:92ff:ffff:ffff:ffff:ffff:ffff:ffff
148ff93:9300::/24ff93:93ff:ffff:ffff:ffff:ffff:ffff:ffff
149ff93:9400::/24ff93:94ff:ffff:ffff:ffff:ffff:ffff:ffff
150ff93:9500::/24ff93:95ff:ffff:ffff:ffff:ffff:ffff:ffff
151ff93:9600::/24ff93:96ff:ffff:ffff:ffff:ffff:ffff:ffff
152ff93:9700::/24ff93:97ff:ffff:ffff:ffff:ffff:ffff:ffff
153ff93:9800::/24ff93:98ff:ffff:ffff:ffff:ffff:ffff:ffff
154ff93:9900::/24ff93:99ff:ffff:ffff:ffff:ffff:ffff:ffff
155ff93:9a00::/24ff93:9aff:ffff:ffff:ffff:ffff:ffff:ffff
156ff93:9b00::/24ff93:9bff:ffff:ffff:ffff:ffff:ffff:ffff
157ff93:9c00::/24ff93:9cff:ffff:ffff:ffff:ffff:ffff:ffff
158ff93:9d00::/24ff93:9dff:ffff:ffff:ffff:ffff:ffff:ffff
159ff93:9e00::/24ff93:9eff:ffff:ffff:ffff:ffff:ffff:ffff
160ff93:9f00::/24ff93:9fff:ffff:ffff:ffff:ffff:ffff:ffff
161ff93:a000::/24ff93:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
162ff93:a100::/24ff93:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
163ff93:a200::/24ff93:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
164ff93:a300::/24ff93:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
165ff93:a400::/24ff93:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
166ff93:a500::/24ff93:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
167ff93:a600::/24ff93:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
168ff93:a700::/24ff93:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
169ff93:a800::/24ff93:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
170ff93:a900::/24ff93:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
171ff93:aa00::/24ff93:aaff:ffff:ffff:ffff:ffff:ffff:ffff
172ff93:ab00::/24ff93:abff:ffff:ffff:ffff:ffff:ffff:ffff
173ff93:ac00::/24ff93:acff:ffff:ffff:ffff:ffff:ffff:ffff
174ff93:ad00::/24ff93:adff:ffff:ffff:ffff:ffff:ffff:ffff
175ff93:ae00::/24ff93:aeff:ffff:ffff:ffff:ffff:ffff:ffff
176ff93:af00::/24ff93:afff:ffff:ffff:ffff:ffff:ffff:ffff
177ff93:b000::/24ff93:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
178ff93:b100::/24ff93:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
179ff93:b200::/24ff93:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
180ff93:b300::/24ff93:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
181ff93:b400::/24ff93:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
182ff93:b500::/24ff93:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
183ff93:b600::/24ff93:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
184ff93:b700::/24ff93:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
185ff93:b800::/24ff93:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
186ff93:b900::/24ff93:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
187ff93:ba00::/24ff93:baff:ffff:ffff:ffff:ffff:ffff:ffff
188ff93:bb00::/24ff93:bbff:ffff:ffff:ffff:ffff:ffff:ffff
189ff93:bc00::/24ff93:bcff:ffff:ffff:ffff:ffff:ffff:ffff
190ff93:bd00::/24ff93:bdff:ffff:ffff:ffff:ffff:ffff:ffff
191ff93:be00::/24ff93:beff:ffff:ffff:ffff:ffff:ffff:ffff
192ff93:bf00::/24ff93:bfff:ffff:ffff:ffff:ffff:ffff:ffff
193ff93:c000::/24ff93:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
194ff93:c100::/24ff93:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
195ff93:c200::/24ff93:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
196ff93:c300::/24ff93:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
197ff93:c400::/24ff93:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
198ff93:c500::/24ff93:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
199ff93:c600::/24ff93:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
200ff93:c700::/24ff93:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
201ff93:c800::/24ff93:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
202ff93:c900::/24ff93:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
203ff93:ca00::/24ff93:caff:ffff:ffff:ffff:ffff:ffff:ffff
204ff93:cb00::/24ff93:cbff:ffff:ffff:ffff:ffff:ffff:ffff
205ff93:cc00::/24ff93:ccff:ffff:ffff:ffff:ffff:ffff:ffff
206ff93:cd00::/24ff93:cdff:ffff:ffff:ffff:ffff:ffff:ffff
207ff93:ce00::/24ff93:ceff:ffff:ffff:ffff:ffff:ffff:ffff
208ff93:cf00::/24ff93:cfff:ffff:ffff:ffff:ffff:ffff:ffff
209ff93:d000::/24ff93:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
210ff93:d100::/24ff93:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
211ff93:d200::/24ff93:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
212ff93:d300::/24ff93:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
213ff93:d400::/24ff93:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
214ff93:d500::/24ff93:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
215ff93:d600::/24ff93:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
216ff93:d700::/24ff93:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
217ff93:d800::/24ff93:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
218ff93:d900::/24ff93:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
219ff93:da00::/24ff93:daff:ffff:ffff:ffff:ffff:ffff:ffff
220ff93:db00::/24ff93:dbff:ffff:ffff:ffff:ffff:ffff:ffff
221ff93:dc00::/24ff93:dcff:ffff:ffff:ffff:ffff:ffff:ffff
222ff93:dd00::/24ff93:ddff:ffff:ffff:ffff:ffff:ffff:ffff
223ff93:de00::/24ff93:deff:ffff:ffff:ffff:ffff:ffff:ffff
224ff93:df00::/24ff93:dfff:ffff:ffff:ffff:ffff:ffff:ffff
225ff93:e000::/24ff93:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
226ff93:e100::/24ff93:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
227ff93:e200::/24ff93:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
228ff93:e300::/24ff93:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
229ff93:e400::/24ff93:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
230ff93:e500::/24ff93:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
231ff93:e600::/24ff93:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
232ff93:e700::/24ff93:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
233ff93:e800::/24ff93:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
234ff93:e900::/24ff93:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
235ff93:ea00::/24ff93:eaff:ffff:ffff:ffff:ffff:ffff:ffff
236ff93:eb00::/24ff93:ebff:ffff:ffff:ffff:ffff:ffff:ffff
237ff93:ec00::/24ff93:ecff:ffff:ffff:ffff:ffff:ffff:ffff
238ff93:ed00::/24ff93:edff:ffff:ffff:ffff:ffff:ffff:ffff
239ff93:ee00::/24ff93:eeff:ffff:ffff:ffff:ffff:ffff:ffff
240ff93:ef00::/24ff93:efff:ffff:ffff:ffff:ffff:ffff:ffff
241ff93:f000::/24ff93:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
242ff93:f100::/24ff93:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
243ff93:f200::/24ff93:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
244ff93:f300::/24ff93:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
245ff93:f400::/24ff93:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
246ff93:f500::/24ff93:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
247ff93:f600::/24ff93:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
248ff93:f700::/24ff93:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
249ff93:f800::/24ff93:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
250ff93:f900::/24ff93:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
251ff93:fa00::/24ff93:faff:ffff:ffff:ffff:ffff:ffff:ffff
252ff93:fb00::/24ff93:fbff:ffff:ffff:ffff:ffff:ffff:ffff
253ff93:fc00::/24ff93:fcff:ffff:ffff:ffff:ffff:ffff:ffff
254ff93:fd00::/24ff93:fdff:ffff:ffff:ffff:ffff:ffff:ffff
255ff93:fe00::/24ff93:feff:ffff:ffff:ffff:ffff:ffff:ffff
256ff93:ff00::/24ff93: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.