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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
ff48::/16
First address
ff48::
Last address
ff48: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
ff48:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
8.4.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)

ff48::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
1ff48::/24ff48:ff:ffff:ffff:ffff:ffff:ffff:ffff
2ff48:100::/24ff48:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3ff48:200::/24ff48:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4ff48:300::/24ff48:3ff:ffff:ffff:ffff:ffff:ffff:ffff
5ff48:400::/24ff48:4ff:ffff:ffff:ffff:ffff:ffff:ffff
6ff48:500::/24ff48:5ff:ffff:ffff:ffff:ffff:ffff:ffff
7ff48:600::/24ff48:6ff:ffff:ffff:ffff:ffff:ffff:ffff
8ff48:700::/24ff48:7ff:ffff:ffff:ffff:ffff:ffff:ffff
9ff48:800::/24ff48:8ff:ffff:ffff:ffff:ffff:ffff:ffff
10ff48:900::/24ff48:9ff:ffff:ffff:ffff:ffff:ffff:ffff
11ff48:a00::/24ff48:aff:ffff:ffff:ffff:ffff:ffff:ffff
12ff48:b00::/24ff48:bff:ffff:ffff:ffff:ffff:ffff:ffff
13ff48:c00::/24ff48:cff:ffff:ffff:ffff:ffff:ffff:ffff
14ff48:d00::/24ff48:dff:ffff:ffff:ffff:ffff:ffff:ffff
15ff48:e00::/24ff48:eff:ffff:ffff:ffff:ffff:ffff:ffff
16ff48:f00::/24ff48:fff:ffff:ffff:ffff:ffff:ffff:ffff
17ff48:1000::/24ff48:10ff:ffff:ffff:ffff:ffff:ffff:ffff
18ff48:1100::/24ff48:11ff:ffff:ffff:ffff:ffff:ffff:ffff
19ff48:1200::/24ff48:12ff:ffff:ffff:ffff:ffff:ffff:ffff
20ff48:1300::/24ff48:13ff:ffff:ffff:ffff:ffff:ffff:ffff
21ff48:1400::/24ff48:14ff:ffff:ffff:ffff:ffff:ffff:ffff
22ff48:1500::/24ff48:15ff:ffff:ffff:ffff:ffff:ffff:ffff
23ff48:1600::/24ff48:16ff:ffff:ffff:ffff:ffff:ffff:ffff
24ff48:1700::/24ff48:17ff:ffff:ffff:ffff:ffff:ffff:ffff
25ff48:1800::/24ff48:18ff:ffff:ffff:ffff:ffff:ffff:ffff
26ff48:1900::/24ff48:19ff:ffff:ffff:ffff:ffff:ffff:ffff
27ff48:1a00::/24ff48:1aff:ffff:ffff:ffff:ffff:ffff:ffff
28ff48:1b00::/24ff48:1bff:ffff:ffff:ffff:ffff:ffff:ffff
29ff48:1c00::/24ff48:1cff:ffff:ffff:ffff:ffff:ffff:ffff
30ff48:1d00::/24ff48:1dff:ffff:ffff:ffff:ffff:ffff:ffff
31ff48:1e00::/24ff48:1eff:ffff:ffff:ffff:ffff:ffff:ffff
32ff48:1f00::/24ff48:1fff:ffff:ffff:ffff:ffff:ffff:ffff
33ff48:2000::/24ff48:20ff:ffff:ffff:ffff:ffff:ffff:ffff
34ff48:2100::/24ff48:21ff:ffff:ffff:ffff:ffff:ffff:ffff
35ff48:2200::/24ff48:22ff:ffff:ffff:ffff:ffff:ffff:ffff
36ff48:2300::/24ff48:23ff:ffff:ffff:ffff:ffff:ffff:ffff
37ff48:2400::/24ff48:24ff:ffff:ffff:ffff:ffff:ffff:ffff
38ff48:2500::/24ff48:25ff:ffff:ffff:ffff:ffff:ffff:ffff
39ff48:2600::/24ff48:26ff:ffff:ffff:ffff:ffff:ffff:ffff
40ff48:2700::/24ff48:27ff:ffff:ffff:ffff:ffff:ffff:ffff
41ff48:2800::/24ff48:28ff:ffff:ffff:ffff:ffff:ffff:ffff
42ff48:2900::/24ff48:29ff:ffff:ffff:ffff:ffff:ffff:ffff
43ff48:2a00::/24ff48:2aff:ffff:ffff:ffff:ffff:ffff:ffff
44ff48:2b00::/24ff48:2bff:ffff:ffff:ffff:ffff:ffff:ffff
45ff48:2c00::/24ff48:2cff:ffff:ffff:ffff:ffff:ffff:ffff
46ff48:2d00::/24ff48:2dff:ffff:ffff:ffff:ffff:ffff:ffff
47ff48:2e00::/24ff48:2eff:ffff:ffff:ffff:ffff:ffff:ffff
48ff48:2f00::/24ff48:2fff:ffff:ffff:ffff:ffff:ffff:ffff
49ff48:3000::/24ff48:30ff:ffff:ffff:ffff:ffff:ffff:ffff
50ff48:3100::/24ff48:31ff:ffff:ffff:ffff:ffff:ffff:ffff
51ff48:3200::/24ff48:32ff:ffff:ffff:ffff:ffff:ffff:ffff
52ff48:3300::/24ff48:33ff:ffff:ffff:ffff:ffff:ffff:ffff
53ff48:3400::/24ff48:34ff:ffff:ffff:ffff:ffff:ffff:ffff
54ff48:3500::/24ff48:35ff:ffff:ffff:ffff:ffff:ffff:ffff
55ff48:3600::/24ff48:36ff:ffff:ffff:ffff:ffff:ffff:ffff
56ff48:3700::/24ff48:37ff:ffff:ffff:ffff:ffff:ffff:ffff
57ff48:3800::/24ff48:38ff:ffff:ffff:ffff:ffff:ffff:ffff
58ff48:3900::/24ff48:39ff:ffff:ffff:ffff:ffff:ffff:ffff
59ff48:3a00::/24ff48:3aff:ffff:ffff:ffff:ffff:ffff:ffff
60ff48:3b00::/24ff48:3bff:ffff:ffff:ffff:ffff:ffff:ffff
61ff48:3c00::/24ff48:3cff:ffff:ffff:ffff:ffff:ffff:ffff
62ff48:3d00::/24ff48:3dff:ffff:ffff:ffff:ffff:ffff:ffff
63ff48:3e00::/24ff48:3eff:ffff:ffff:ffff:ffff:ffff:ffff
64ff48:3f00::/24ff48:3fff:ffff:ffff:ffff:ffff:ffff:ffff
65ff48:4000::/24ff48:40ff:ffff:ffff:ffff:ffff:ffff:ffff
66ff48:4100::/24ff48:41ff:ffff:ffff:ffff:ffff:ffff:ffff
67ff48:4200::/24ff48:42ff:ffff:ffff:ffff:ffff:ffff:ffff
68ff48:4300::/24ff48:43ff:ffff:ffff:ffff:ffff:ffff:ffff
69ff48:4400::/24ff48:44ff:ffff:ffff:ffff:ffff:ffff:ffff
70ff48:4500::/24ff48:45ff:ffff:ffff:ffff:ffff:ffff:ffff
71ff48:4600::/24ff48:46ff:ffff:ffff:ffff:ffff:ffff:ffff
72ff48:4700::/24ff48:47ff:ffff:ffff:ffff:ffff:ffff:ffff
73ff48:4800::/24ff48:48ff:ffff:ffff:ffff:ffff:ffff:ffff
74ff48:4900::/24ff48:49ff:ffff:ffff:ffff:ffff:ffff:ffff
75ff48:4a00::/24ff48:4aff:ffff:ffff:ffff:ffff:ffff:ffff
76ff48:4b00::/24ff48:4bff:ffff:ffff:ffff:ffff:ffff:ffff
77ff48:4c00::/24ff48:4cff:ffff:ffff:ffff:ffff:ffff:ffff
78ff48:4d00::/24ff48:4dff:ffff:ffff:ffff:ffff:ffff:ffff
79ff48:4e00::/24ff48:4eff:ffff:ffff:ffff:ffff:ffff:ffff
80ff48:4f00::/24ff48:4fff:ffff:ffff:ffff:ffff:ffff:ffff
81ff48:5000::/24ff48:50ff:ffff:ffff:ffff:ffff:ffff:ffff
82ff48:5100::/24ff48:51ff:ffff:ffff:ffff:ffff:ffff:ffff
83ff48:5200::/24ff48:52ff:ffff:ffff:ffff:ffff:ffff:ffff
84ff48:5300::/24ff48:53ff:ffff:ffff:ffff:ffff:ffff:ffff
85ff48:5400::/24ff48:54ff:ffff:ffff:ffff:ffff:ffff:ffff
86ff48:5500::/24ff48:55ff:ffff:ffff:ffff:ffff:ffff:ffff
87ff48:5600::/24ff48:56ff:ffff:ffff:ffff:ffff:ffff:ffff
88ff48:5700::/24ff48:57ff:ffff:ffff:ffff:ffff:ffff:ffff
89ff48:5800::/24ff48:58ff:ffff:ffff:ffff:ffff:ffff:ffff
90ff48:5900::/24ff48:59ff:ffff:ffff:ffff:ffff:ffff:ffff
91ff48:5a00::/24ff48:5aff:ffff:ffff:ffff:ffff:ffff:ffff
92ff48:5b00::/24ff48:5bff:ffff:ffff:ffff:ffff:ffff:ffff
93ff48:5c00::/24ff48:5cff:ffff:ffff:ffff:ffff:ffff:ffff
94ff48:5d00::/24ff48:5dff:ffff:ffff:ffff:ffff:ffff:ffff
95ff48:5e00::/24ff48:5eff:ffff:ffff:ffff:ffff:ffff:ffff
96ff48:5f00::/24ff48:5fff:ffff:ffff:ffff:ffff:ffff:ffff
97ff48:6000::/24ff48:60ff:ffff:ffff:ffff:ffff:ffff:ffff
98ff48:6100::/24ff48:61ff:ffff:ffff:ffff:ffff:ffff:ffff
99ff48:6200::/24ff48:62ff:ffff:ffff:ffff:ffff:ffff:ffff
100ff48:6300::/24ff48:63ff:ffff:ffff:ffff:ffff:ffff:ffff
101ff48:6400::/24ff48:64ff:ffff:ffff:ffff:ffff:ffff:ffff
102ff48:6500::/24ff48:65ff:ffff:ffff:ffff:ffff:ffff:ffff
103ff48:6600::/24ff48:66ff:ffff:ffff:ffff:ffff:ffff:ffff
104ff48:6700::/24ff48:67ff:ffff:ffff:ffff:ffff:ffff:ffff
105ff48:6800::/24ff48:68ff:ffff:ffff:ffff:ffff:ffff:ffff
106ff48:6900::/24ff48:69ff:ffff:ffff:ffff:ffff:ffff:ffff
107ff48:6a00::/24ff48:6aff:ffff:ffff:ffff:ffff:ffff:ffff
108ff48:6b00::/24ff48:6bff:ffff:ffff:ffff:ffff:ffff:ffff
109ff48:6c00::/24ff48:6cff:ffff:ffff:ffff:ffff:ffff:ffff
110ff48:6d00::/24ff48:6dff:ffff:ffff:ffff:ffff:ffff:ffff
111ff48:6e00::/24ff48:6eff:ffff:ffff:ffff:ffff:ffff:ffff
112ff48:6f00::/24ff48:6fff:ffff:ffff:ffff:ffff:ffff:ffff
113ff48:7000::/24ff48:70ff:ffff:ffff:ffff:ffff:ffff:ffff
114ff48:7100::/24ff48:71ff:ffff:ffff:ffff:ffff:ffff:ffff
115ff48:7200::/24ff48:72ff:ffff:ffff:ffff:ffff:ffff:ffff
116ff48:7300::/24ff48:73ff:ffff:ffff:ffff:ffff:ffff:ffff
117ff48:7400::/24ff48:74ff:ffff:ffff:ffff:ffff:ffff:ffff
118ff48:7500::/24ff48:75ff:ffff:ffff:ffff:ffff:ffff:ffff
119ff48:7600::/24ff48:76ff:ffff:ffff:ffff:ffff:ffff:ffff
120ff48:7700::/24ff48:77ff:ffff:ffff:ffff:ffff:ffff:ffff
121ff48:7800::/24ff48:78ff:ffff:ffff:ffff:ffff:ffff:ffff
122ff48:7900::/24ff48:79ff:ffff:ffff:ffff:ffff:ffff:ffff
123ff48:7a00::/24ff48:7aff:ffff:ffff:ffff:ffff:ffff:ffff
124ff48:7b00::/24ff48:7bff:ffff:ffff:ffff:ffff:ffff:ffff
125ff48:7c00::/24ff48:7cff:ffff:ffff:ffff:ffff:ffff:ffff
126ff48:7d00::/24ff48:7dff:ffff:ffff:ffff:ffff:ffff:ffff
127ff48:7e00::/24ff48:7eff:ffff:ffff:ffff:ffff:ffff:ffff
128ff48:7f00::/24ff48:7fff:ffff:ffff:ffff:ffff:ffff:ffff
129ff48:8000::/24ff48:80ff:ffff:ffff:ffff:ffff:ffff:ffff
130ff48:8100::/24ff48:81ff:ffff:ffff:ffff:ffff:ffff:ffff
131ff48:8200::/24ff48:82ff:ffff:ffff:ffff:ffff:ffff:ffff
132ff48:8300::/24ff48:83ff:ffff:ffff:ffff:ffff:ffff:ffff
133ff48:8400::/24ff48:84ff:ffff:ffff:ffff:ffff:ffff:ffff
134ff48:8500::/24ff48:85ff:ffff:ffff:ffff:ffff:ffff:ffff
135ff48:8600::/24ff48:86ff:ffff:ffff:ffff:ffff:ffff:ffff
136ff48:8700::/24ff48:87ff:ffff:ffff:ffff:ffff:ffff:ffff
137ff48:8800::/24ff48:88ff:ffff:ffff:ffff:ffff:ffff:ffff
138ff48:8900::/24ff48:89ff:ffff:ffff:ffff:ffff:ffff:ffff
139ff48:8a00::/24ff48:8aff:ffff:ffff:ffff:ffff:ffff:ffff
140ff48:8b00::/24ff48:8bff:ffff:ffff:ffff:ffff:ffff:ffff
141ff48:8c00::/24ff48:8cff:ffff:ffff:ffff:ffff:ffff:ffff
142ff48:8d00::/24ff48:8dff:ffff:ffff:ffff:ffff:ffff:ffff
143ff48:8e00::/24ff48:8eff:ffff:ffff:ffff:ffff:ffff:ffff
144ff48:8f00::/24ff48:8fff:ffff:ffff:ffff:ffff:ffff:ffff
145ff48:9000::/24ff48:90ff:ffff:ffff:ffff:ffff:ffff:ffff
146ff48:9100::/24ff48:91ff:ffff:ffff:ffff:ffff:ffff:ffff
147ff48:9200::/24ff48:92ff:ffff:ffff:ffff:ffff:ffff:ffff
148ff48:9300::/24ff48:93ff:ffff:ffff:ffff:ffff:ffff:ffff
149ff48:9400::/24ff48:94ff:ffff:ffff:ffff:ffff:ffff:ffff
150ff48:9500::/24ff48:95ff:ffff:ffff:ffff:ffff:ffff:ffff
151ff48:9600::/24ff48:96ff:ffff:ffff:ffff:ffff:ffff:ffff
152ff48:9700::/24ff48:97ff:ffff:ffff:ffff:ffff:ffff:ffff
153ff48:9800::/24ff48:98ff:ffff:ffff:ffff:ffff:ffff:ffff
154ff48:9900::/24ff48:99ff:ffff:ffff:ffff:ffff:ffff:ffff
155ff48:9a00::/24ff48:9aff:ffff:ffff:ffff:ffff:ffff:ffff
156ff48:9b00::/24ff48:9bff:ffff:ffff:ffff:ffff:ffff:ffff
157ff48:9c00::/24ff48:9cff:ffff:ffff:ffff:ffff:ffff:ffff
158ff48:9d00::/24ff48:9dff:ffff:ffff:ffff:ffff:ffff:ffff
159ff48:9e00::/24ff48:9eff:ffff:ffff:ffff:ffff:ffff:ffff
160ff48:9f00::/24ff48:9fff:ffff:ffff:ffff:ffff:ffff:ffff
161ff48:a000::/24ff48:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
162ff48:a100::/24ff48:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
163ff48:a200::/24ff48:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
164ff48:a300::/24ff48:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
165ff48:a400::/24ff48:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
166ff48:a500::/24ff48:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
167ff48:a600::/24ff48:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
168ff48:a700::/24ff48:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
169ff48:a800::/24ff48:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
170ff48:a900::/24ff48:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
171ff48:aa00::/24ff48:aaff:ffff:ffff:ffff:ffff:ffff:ffff
172ff48:ab00::/24ff48:abff:ffff:ffff:ffff:ffff:ffff:ffff
173ff48:ac00::/24ff48:acff:ffff:ffff:ffff:ffff:ffff:ffff
174ff48:ad00::/24ff48:adff:ffff:ffff:ffff:ffff:ffff:ffff
175ff48:ae00::/24ff48:aeff:ffff:ffff:ffff:ffff:ffff:ffff
176ff48:af00::/24ff48:afff:ffff:ffff:ffff:ffff:ffff:ffff
177ff48:b000::/24ff48:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
178ff48:b100::/24ff48:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
179ff48:b200::/24ff48:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
180ff48:b300::/24ff48:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
181ff48:b400::/24ff48:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
182ff48:b500::/24ff48:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
183ff48:b600::/24ff48:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
184ff48:b700::/24ff48:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
185ff48:b800::/24ff48:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
186ff48:b900::/24ff48:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
187ff48:ba00::/24ff48:baff:ffff:ffff:ffff:ffff:ffff:ffff
188ff48:bb00::/24ff48:bbff:ffff:ffff:ffff:ffff:ffff:ffff
189ff48:bc00::/24ff48:bcff:ffff:ffff:ffff:ffff:ffff:ffff
190ff48:bd00::/24ff48:bdff:ffff:ffff:ffff:ffff:ffff:ffff
191ff48:be00::/24ff48:beff:ffff:ffff:ffff:ffff:ffff:ffff
192ff48:bf00::/24ff48:bfff:ffff:ffff:ffff:ffff:ffff:ffff
193ff48:c000::/24ff48:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
194ff48:c100::/24ff48:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
195ff48:c200::/24ff48:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
196ff48:c300::/24ff48:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
197ff48:c400::/24ff48:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
198ff48:c500::/24ff48:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
199ff48:c600::/24ff48:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
200ff48:c700::/24ff48:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
201ff48:c800::/24ff48:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
202ff48:c900::/24ff48:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
203ff48:ca00::/24ff48:caff:ffff:ffff:ffff:ffff:ffff:ffff
204ff48:cb00::/24ff48:cbff:ffff:ffff:ffff:ffff:ffff:ffff
205ff48:cc00::/24ff48:ccff:ffff:ffff:ffff:ffff:ffff:ffff
206ff48:cd00::/24ff48:cdff:ffff:ffff:ffff:ffff:ffff:ffff
207ff48:ce00::/24ff48:ceff:ffff:ffff:ffff:ffff:ffff:ffff
208ff48:cf00::/24ff48:cfff:ffff:ffff:ffff:ffff:ffff:ffff
209ff48:d000::/24ff48:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
210ff48:d100::/24ff48:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
211ff48:d200::/24ff48:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
212ff48:d300::/24ff48:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
213ff48:d400::/24ff48:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
214ff48:d500::/24ff48:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
215ff48:d600::/24ff48:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
216ff48:d700::/24ff48:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
217ff48:d800::/24ff48:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
218ff48:d900::/24ff48:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
219ff48:da00::/24ff48:daff:ffff:ffff:ffff:ffff:ffff:ffff
220ff48:db00::/24ff48:dbff:ffff:ffff:ffff:ffff:ffff:ffff
221ff48:dc00::/24ff48:dcff:ffff:ffff:ffff:ffff:ffff:ffff
222ff48:dd00::/24ff48:ddff:ffff:ffff:ffff:ffff:ffff:ffff
223ff48:de00::/24ff48:deff:ffff:ffff:ffff:ffff:ffff:ffff
224ff48:df00::/24ff48:dfff:ffff:ffff:ffff:ffff:ffff:ffff
225ff48:e000::/24ff48:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
226ff48:e100::/24ff48:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
227ff48:e200::/24ff48:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
228ff48:e300::/24ff48:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
229ff48:e400::/24ff48:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
230ff48:e500::/24ff48:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
231ff48:e600::/24ff48:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
232ff48:e700::/24ff48:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
233ff48:e800::/24ff48:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
234ff48:e900::/24ff48:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
235ff48:ea00::/24ff48:eaff:ffff:ffff:ffff:ffff:ffff:ffff
236ff48:eb00::/24ff48:ebff:ffff:ffff:ffff:ffff:ffff:ffff
237ff48:ec00::/24ff48:ecff:ffff:ffff:ffff:ffff:ffff:ffff
238ff48:ed00::/24ff48:edff:ffff:ffff:ffff:ffff:ffff:ffff
239ff48:ee00::/24ff48:eeff:ffff:ffff:ffff:ffff:ffff:ffff
240ff48:ef00::/24ff48:efff:ffff:ffff:ffff:ffff:ffff:ffff
241ff48:f000::/24ff48:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
242ff48:f100::/24ff48:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
243ff48:f200::/24ff48:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
244ff48:f300::/24ff48:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
245ff48:f400::/24ff48:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
246ff48:f500::/24ff48:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
247ff48:f600::/24ff48:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
248ff48:f700::/24ff48:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
249ff48:f800::/24ff48:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
250ff48:f900::/24ff48:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
251ff48:fa00::/24ff48:faff:ffff:ffff:ffff:ffff:ffff:ffff
252ff48:fb00::/24ff48:fbff:ffff:ffff:ffff:ffff:ffff:ffff
253ff48:fc00::/24ff48:fcff:ffff:ffff:ffff:ffff:ffff:ffff
254ff48:fd00::/24ff48:fdff:ffff:ffff:ffff:ffff:ffff:ffff
255ff48:fe00::/24ff48:feff:ffff:ffff:ffff:ffff:ffff:ffff
256ff48:ff00::/24ff48: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.