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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/24
Addresses2^104
/64 networks2^40
Network
ff76:ec00::/24
First address
ff76:ec00::
Last address
ff76:ecff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
20,282,409,603,651,670,423,947,251,286,016 (2^104)
/64 networks (LANs)
1,099,511,627,776 (2^40)
Full form
ff76:ec00:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
c.e.6.7.f.f.ip6.arpa
Split into smaller subnets/40
/25 (2)/26 (4)/27 (8)/28 (16)/32 (256)/36 (4,096)/40 (65,536)

ff76:ec00::/24 makes 65,536 subnets of /40; the first 256 are listed.

Subnets
#SubnetLast address
1ff76:ec00::/40ff76:ec00:ff:ffff:ffff:ffff:ffff:ffff
2ff76:ec00:100::/40ff76:ec00:1ff:ffff:ffff:ffff:ffff:ffff
3ff76:ec00:200::/40ff76:ec00:2ff:ffff:ffff:ffff:ffff:ffff
4ff76:ec00:300::/40ff76:ec00:3ff:ffff:ffff:ffff:ffff:ffff
5ff76:ec00:400::/40ff76:ec00:4ff:ffff:ffff:ffff:ffff:ffff
6ff76:ec00:500::/40ff76:ec00:5ff:ffff:ffff:ffff:ffff:ffff
7ff76:ec00:600::/40ff76:ec00:6ff:ffff:ffff:ffff:ffff:ffff
8ff76:ec00:700::/40ff76:ec00:7ff:ffff:ffff:ffff:ffff:ffff
9ff76:ec00:800::/40ff76:ec00:8ff:ffff:ffff:ffff:ffff:ffff
10ff76:ec00:900::/40ff76:ec00:9ff:ffff:ffff:ffff:ffff:ffff
11ff76:ec00:a00::/40ff76:ec00:aff:ffff:ffff:ffff:ffff:ffff
12ff76:ec00:b00::/40ff76:ec00:bff:ffff:ffff:ffff:ffff:ffff
13ff76:ec00:c00::/40ff76:ec00:cff:ffff:ffff:ffff:ffff:ffff
14ff76:ec00:d00::/40ff76:ec00:dff:ffff:ffff:ffff:ffff:ffff
15ff76:ec00:e00::/40ff76:ec00:eff:ffff:ffff:ffff:ffff:ffff
16ff76:ec00:f00::/40ff76:ec00:fff:ffff:ffff:ffff:ffff:ffff
17ff76:ec00:1000::/40ff76:ec00:10ff:ffff:ffff:ffff:ffff:ffff
18ff76:ec00:1100::/40ff76:ec00:11ff:ffff:ffff:ffff:ffff:ffff
19ff76:ec00:1200::/40ff76:ec00:12ff:ffff:ffff:ffff:ffff:ffff
20ff76:ec00:1300::/40ff76:ec00:13ff:ffff:ffff:ffff:ffff:ffff
21ff76:ec00:1400::/40ff76:ec00:14ff:ffff:ffff:ffff:ffff:ffff
22ff76:ec00:1500::/40ff76:ec00:15ff:ffff:ffff:ffff:ffff:ffff
23ff76:ec00:1600::/40ff76:ec00:16ff:ffff:ffff:ffff:ffff:ffff
24ff76:ec00:1700::/40ff76:ec00:17ff:ffff:ffff:ffff:ffff:ffff
25ff76:ec00:1800::/40ff76:ec00:18ff:ffff:ffff:ffff:ffff:ffff
26ff76:ec00:1900::/40ff76:ec00:19ff:ffff:ffff:ffff:ffff:ffff
27ff76:ec00:1a00::/40ff76:ec00:1aff:ffff:ffff:ffff:ffff:ffff
28ff76:ec00:1b00::/40ff76:ec00:1bff:ffff:ffff:ffff:ffff:ffff
29ff76:ec00:1c00::/40ff76:ec00:1cff:ffff:ffff:ffff:ffff:ffff
30ff76:ec00:1d00::/40ff76:ec00:1dff:ffff:ffff:ffff:ffff:ffff
31ff76:ec00:1e00::/40ff76:ec00:1eff:ffff:ffff:ffff:ffff:ffff
32ff76:ec00:1f00::/40ff76:ec00:1fff:ffff:ffff:ffff:ffff:ffff
33ff76:ec00:2000::/40ff76:ec00:20ff:ffff:ffff:ffff:ffff:ffff
34ff76:ec00:2100::/40ff76:ec00:21ff:ffff:ffff:ffff:ffff:ffff
35ff76:ec00:2200::/40ff76:ec00:22ff:ffff:ffff:ffff:ffff:ffff
36ff76:ec00:2300::/40ff76:ec00:23ff:ffff:ffff:ffff:ffff:ffff
37ff76:ec00:2400::/40ff76:ec00:24ff:ffff:ffff:ffff:ffff:ffff
38ff76:ec00:2500::/40ff76:ec00:25ff:ffff:ffff:ffff:ffff:ffff
39ff76:ec00:2600::/40ff76:ec00:26ff:ffff:ffff:ffff:ffff:ffff
40ff76:ec00:2700::/40ff76:ec00:27ff:ffff:ffff:ffff:ffff:ffff
41ff76:ec00:2800::/40ff76:ec00:28ff:ffff:ffff:ffff:ffff:ffff
42ff76:ec00:2900::/40ff76:ec00:29ff:ffff:ffff:ffff:ffff:ffff
43ff76:ec00:2a00::/40ff76:ec00:2aff:ffff:ffff:ffff:ffff:ffff
44ff76:ec00:2b00::/40ff76:ec00:2bff:ffff:ffff:ffff:ffff:ffff
45ff76:ec00:2c00::/40ff76:ec00:2cff:ffff:ffff:ffff:ffff:ffff
46ff76:ec00:2d00::/40ff76:ec00:2dff:ffff:ffff:ffff:ffff:ffff
47ff76:ec00:2e00::/40ff76:ec00:2eff:ffff:ffff:ffff:ffff:ffff
48ff76:ec00:2f00::/40ff76:ec00:2fff:ffff:ffff:ffff:ffff:ffff
49ff76:ec00:3000::/40ff76:ec00:30ff:ffff:ffff:ffff:ffff:ffff
50ff76:ec00:3100::/40ff76:ec00:31ff:ffff:ffff:ffff:ffff:ffff
51ff76:ec00:3200::/40ff76:ec00:32ff:ffff:ffff:ffff:ffff:ffff
52ff76:ec00:3300::/40ff76:ec00:33ff:ffff:ffff:ffff:ffff:ffff
53ff76:ec00:3400::/40ff76:ec00:34ff:ffff:ffff:ffff:ffff:ffff
54ff76:ec00:3500::/40ff76:ec00:35ff:ffff:ffff:ffff:ffff:ffff
55ff76:ec00:3600::/40ff76:ec00:36ff:ffff:ffff:ffff:ffff:ffff
56ff76:ec00:3700::/40ff76:ec00:37ff:ffff:ffff:ffff:ffff:ffff
57ff76:ec00:3800::/40ff76:ec00:38ff:ffff:ffff:ffff:ffff:ffff
58ff76:ec00:3900::/40ff76:ec00:39ff:ffff:ffff:ffff:ffff:ffff
59ff76:ec00:3a00::/40ff76:ec00:3aff:ffff:ffff:ffff:ffff:ffff
60ff76:ec00:3b00::/40ff76:ec00:3bff:ffff:ffff:ffff:ffff:ffff
61ff76:ec00:3c00::/40ff76:ec00:3cff:ffff:ffff:ffff:ffff:ffff
62ff76:ec00:3d00::/40ff76:ec00:3dff:ffff:ffff:ffff:ffff:ffff
63ff76:ec00:3e00::/40ff76:ec00:3eff:ffff:ffff:ffff:ffff:ffff
64ff76:ec00:3f00::/40ff76:ec00:3fff:ffff:ffff:ffff:ffff:ffff
65ff76:ec00:4000::/40ff76:ec00:40ff:ffff:ffff:ffff:ffff:ffff
66ff76:ec00:4100::/40ff76:ec00:41ff:ffff:ffff:ffff:ffff:ffff
67ff76:ec00:4200::/40ff76:ec00:42ff:ffff:ffff:ffff:ffff:ffff
68ff76:ec00:4300::/40ff76:ec00:43ff:ffff:ffff:ffff:ffff:ffff
69ff76:ec00:4400::/40ff76:ec00:44ff:ffff:ffff:ffff:ffff:ffff
70ff76:ec00:4500::/40ff76:ec00:45ff:ffff:ffff:ffff:ffff:ffff
71ff76:ec00:4600::/40ff76:ec00:46ff:ffff:ffff:ffff:ffff:ffff
72ff76:ec00:4700::/40ff76:ec00:47ff:ffff:ffff:ffff:ffff:ffff
73ff76:ec00:4800::/40ff76:ec00:48ff:ffff:ffff:ffff:ffff:ffff
74ff76:ec00:4900::/40ff76:ec00:49ff:ffff:ffff:ffff:ffff:ffff
75ff76:ec00:4a00::/40ff76:ec00:4aff:ffff:ffff:ffff:ffff:ffff
76ff76:ec00:4b00::/40ff76:ec00:4bff:ffff:ffff:ffff:ffff:ffff
77ff76:ec00:4c00::/40ff76:ec00:4cff:ffff:ffff:ffff:ffff:ffff
78ff76:ec00:4d00::/40ff76:ec00:4dff:ffff:ffff:ffff:ffff:ffff
79ff76:ec00:4e00::/40ff76:ec00:4eff:ffff:ffff:ffff:ffff:ffff
80ff76:ec00:4f00::/40ff76:ec00:4fff:ffff:ffff:ffff:ffff:ffff
81ff76:ec00:5000::/40ff76:ec00:50ff:ffff:ffff:ffff:ffff:ffff
82ff76:ec00:5100::/40ff76:ec00:51ff:ffff:ffff:ffff:ffff:ffff
83ff76:ec00:5200::/40ff76:ec00:52ff:ffff:ffff:ffff:ffff:ffff
84ff76:ec00:5300::/40ff76:ec00:53ff:ffff:ffff:ffff:ffff:ffff
85ff76:ec00:5400::/40ff76:ec00:54ff:ffff:ffff:ffff:ffff:ffff
86ff76:ec00:5500::/40ff76:ec00:55ff:ffff:ffff:ffff:ffff:ffff
87ff76:ec00:5600::/40ff76:ec00:56ff:ffff:ffff:ffff:ffff:ffff
88ff76:ec00:5700::/40ff76:ec00:57ff:ffff:ffff:ffff:ffff:ffff
89ff76:ec00:5800::/40ff76:ec00:58ff:ffff:ffff:ffff:ffff:ffff
90ff76:ec00:5900::/40ff76:ec00:59ff:ffff:ffff:ffff:ffff:ffff
91ff76:ec00:5a00::/40ff76:ec00:5aff:ffff:ffff:ffff:ffff:ffff
92ff76:ec00:5b00::/40ff76:ec00:5bff:ffff:ffff:ffff:ffff:ffff
93ff76:ec00:5c00::/40ff76:ec00:5cff:ffff:ffff:ffff:ffff:ffff
94ff76:ec00:5d00::/40ff76:ec00:5dff:ffff:ffff:ffff:ffff:ffff
95ff76:ec00:5e00::/40ff76:ec00:5eff:ffff:ffff:ffff:ffff:ffff
96ff76:ec00:5f00::/40ff76:ec00:5fff:ffff:ffff:ffff:ffff:ffff
97ff76:ec00:6000::/40ff76:ec00:60ff:ffff:ffff:ffff:ffff:ffff
98ff76:ec00:6100::/40ff76:ec00:61ff:ffff:ffff:ffff:ffff:ffff
99ff76:ec00:6200::/40ff76:ec00:62ff:ffff:ffff:ffff:ffff:ffff
100ff76:ec00:6300::/40ff76:ec00:63ff:ffff:ffff:ffff:ffff:ffff
101ff76:ec00:6400::/40ff76:ec00:64ff:ffff:ffff:ffff:ffff:ffff
102ff76:ec00:6500::/40ff76:ec00:65ff:ffff:ffff:ffff:ffff:ffff
103ff76:ec00:6600::/40ff76:ec00:66ff:ffff:ffff:ffff:ffff:ffff
104ff76:ec00:6700::/40ff76:ec00:67ff:ffff:ffff:ffff:ffff:ffff
105ff76:ec00:6800::/40ff76:ec00:68ff:ffff:ffff:ffff:ffff:ffff
106ff76:ec00:6900::/40ff76:ec00:69ff:ffff:ffff:ffff:ffff:ffff
107ff76:ec00:6a00::/40ff76:ec00:6aff:ffff:ffff:ffff:ffff:ffff
108ff76:ec00:6b00::/40ff76:ec00:6bff:ffff:ffff:ffff:ffff:ffff
109ff76:ec00:6c00::/40ff76:ec00:6cff:ffff:ffff:ffff:ffff:ffff
110ff76:ec00:6d00::/40ff76:ec00:6dff:ffff:ffff:ffff:ffff:ffff
111ff76:ec00:6e00::/40ff76:ec00:6eff:ffff:ffff:ffff:ffff:ffff
112ff76:ec00:6f00::/40ff76:ec00:6fff:ffff:ffff:ffff:ffff:ffff
113ff76:ec00:7000::/40ff76:ec00:70ff:ffff:ffff:ffff:ffff:ffff
114ff76:ec00:7100::/40ff76:ec00:71ff:ffff:ffff:ffff:ffff:ffff
115ff76:ec00:7200::/40ff76:ec00:72ff:ffff:ffff:ffff:ffff:ffff
116ff76:ec00:7300::/40ff76:ec00:73ff:ffff:ffff:ffff:ffff:ffff
117ff76:ec00:7400::/40ff76:ec00:74ff:ffff:ffff:ffff:ffff:ffff
118ff76:ec00:7500::/40ff76:ec00:75ff:ffff:ffff:ffff:ffff:ffff
119ff76:ec00:7600::/40ff76:ec00:76ff:ffff:ffff:ffff:ffff:ffff
120ff76:ec00:7700::/40ff76:ec00:77ff:ffff:ffff:ffff:ffff:ffff
121ff76:ec00:7800::/40ff76:ec00:78ff:ffff:ffff:ffff:ffff:ffff
122ff76:ec00:7900::/40ff76:ec00:79ff:ffff:ffff:ffff:ffff:ffff
123ff76:ec00:7a00::/40ff76:ec00:7aff:ffff:ffff:ffff:ffff:ffff
124ff76:ec00:7b00::/40ff76:ec00:7bff:ffff:ffff:ffff:ffff:ffff
125ff76:ec00:7c00::/40ff76:ec00:7cff:ffff:ffff:ffff:ffff:ffff
126ff76:ec00:7d00::/40ff76:ec00:7dff:ffff:ffff:ffff:ffff:ffff
127ff76:ec00:7e00::/40ff76:ec00:7eff:ffff:ffff:ffff:ffff:ffff
128ff76:ec00:7f00::/40ff76:ec00:7fff:ffff:ffff:ffff:ffff:ffff
129ff76:ec00:8000::/40ff76:ec00:80ff:ffff:ffff:ffff:ffff:ffff
130ff76:ec00:8100::/40ff76:ec00:81ff:ffff:ffff:ffff:ffff:ffff
131ff76:ec00:8200::/40ff76:ec00:82ff:ffff:ffff:ffff:ffff:ffff
132ff76:ec00:8300::/40ff76:ec00:83ff:ffff:ffff:ffff:ffff:ffff
133ff76:ec00:8400::/40ff76:ec00:84ff:ffff:ffff:ffff:ffff:ffff
134ff76:ec00:8500::/40ff76:ec00:85ff:ffff:ffff:ffff:ffff:ffff
135ff76:ec00:8600::/40ff76:ec00:86ff:ffff:ffff:ffff:ffff:ffff
136ff76:ec00:8700::/40ff76:ec00:87ff:ffff:ffff:ffff:ffff:ffff
137ff76:ec00:8800::/40ff76:ec00:88ff:ffff:ffff:ffff:ffff:ffff
138ff76:ec00:8900::/40ff76:ec00:89ff:ffff:ffff:ffff:ffff:ffff
139ff76:ec00:8a00::/40ff76:ec00:8aff:ffff:ffff:ffff:ffff:ffff
140ff76:ec00:8b00::/40ff76:ec00:8bff:ffff:ffff:ffff:ffff:ffff
141ff76:ec00:8c00::/40ff76:ec00:8cff:ffff:ffff:ffff:ffff:ffff
142ff76:ec00:8d00::/40ff76:ec00:8dff:ffff:ffff:ffff:ffff:ffff
143ff76:ec00:8e00::/40ff76:ec00:8eff:ffff:ffff:ffff:ffff:ffff
144ff76:ec00:8f00::/40ff76:ec00:8fff:ffff:ffff:ffff:ffff:ffff
145ff76:ec00:9000::/40ff76:ec00:90ff:ffff:ffff:ffff:ffff:ffff
146ff76:ec00:9100::/40ff76:ec00:91ff:ffff:ffff:ffff:ffff:ffff
147ff76:ec00:9200::/40ff76:ec00:92ff:ffff:ffff:ffff:ffff:ffff
148ff76:ec00:9300::/40ff76:ec00:93ff:ffff:ffff:ffff:ffff:ffff
149ff76:ec00:9400::/40ff76:ec00:94ff:ffff:ffff:ffff:ffff:ffff
150ff76:ec00:9500::/40ff76:ec00:95ff:ffff:ffff:ffff:ffff:ffff
151ff76:ec00:9600::/40ff76:ec00:96ff:ffff:ffff:ffff:ffff:ffff
152ff76:ec00:9700::/40ff76:ec00:97ff:ffff:ffff:ffff:ffff:ffff
153ff76:ec00:9800::/40ff76:ec00:98ff:ffff:ffff:ffff:ffff:ffff
154ff76:ec00:9900::/40ff76:ec00:99ff:ffff:ffff:ffff:ffff:ffff
155ff76:ec00:9a00::/40ff76:ec00:9aff:ffff:ffff:ffff:ffff:ffff
156ff76:ec00:9b00::/40ff76:ec00:9bff:ffff:ffff:ffff:ffff:ffff
157ff76:ec00:9c00::/40ff76:ec00:9cff:ffff:ffff:ffff:ffff:ffff
158ff76:ec00:9d00::/40ff76:ec00:9dff:ffff:ffff:ffff:ffff:ffff
159ff76:ec00:9e00::/40ff76:ec00:9eff:ffff:ffff:ffff:ffff:ffff
160ff76:ec00:9f00::/40ff76:ec00:9fff:ffff:ffff:ffff:ffff:ffff
161ff76:ec00:a000::/40ff76:ec00:a0ff:ffff:ffff:ffff:ffff:ffff
162ff76:ec00:a100::/40ff76:ec00:a1ff:ffff:ffff:ffff:ffff:ffff
163ff76:ec00:a200::/40ff76:ec00:a2ff:ffff:ffff:ffff:ffff:ffff
164ff76:ec00:a300::/40ff76:ec00:a3ff:ffff:ffff:ffff:ffff:ffff
165ff76:ec00:a400::/40ff76:ec00:a4ff:ffff:ffff:ffff:ffff:ffff
166ff76:ec00:a500::/40ff76:ec00:a5ff:ffff:ffff:ffff:ffff:ffff
167ff76:ec00:a600::/40ff76:ec00:a6ff:ffff:ffff:ffff:ffff:ffff
168ff76:ec00:a700::/40ff76:ec00:a7ff:ffff:ffff:ffff:ffff:ffff
169ff76:ec00:a800::/40ff76:ec00:a8ff:ffff:ffff:ffff:ffff:ffff
170ff76:ec00:a900::/40ff76:ec00:a9ff:ffff:ffff:ffff:ffff:ffff
171ff76:ec00:aa00::/40ff76:ec00:aaff:ffff:ffff:ffff:ffff:ffff
172ff76:ec00:ab00::/40ff76:ec00:abff:ffff:ffff:ffff:ffff:ffff
173ff76:ec00:ac00::/40ff76:ec00:acff:ffff:ffff:ffff:ffff:ffff
174ff76:ec00:ad00::/40ff76:ec00:adff:ffff:ffff:ffff:ffff:ffff
175ff76:ec00:ae00::/40ff76:ec00:aeff:ffff:ffff:ffff:ffff:ffff
176ff76:ec00:af00::/40ff76:ec00:afff:ffff:ffff:ffff:ffff:ffff
177ff76:ec00:b000::/40ff76:ec00:b0ff:ffff:ffff:ffff:ffff:ffff
178ff76:ec00:b100::/40ff76:ec00:b1ff:ffff:ffff:ffff:ffff:ffff
179ff76:ec00:b200::/40ff76:ec00:b2ff:ffff:ffff:ffff:ffff:ffff
180ff76:ec00:b300::/40ff76:ec00:b3ff:ffff:ffff:ffff:ffff:ffff
181ff76:ec00:b400::/40ff76:ec00:b4ff:ffff:ffff:ffff:ffff:ffff
182ff76:ec00:b500::/40ff76:ec00:b5ff:ffff:ffff:ffff:ffff:ffff
183ff76:ec00:b600::/40ff76:ec00:b6ff:ffff:ffff:ffff:ffff:ffff
184ff76:ec00:b700::/40ff76:ec00:b7ff:ffff:ffff:ffff:ffff:ffff
185ff76:ec00:b800::/40ff76:ec00:b8ff:ffff:ffff:ffff:ffff:ffff
186ff76:ec00:b900::/40ff76:ec00:b9ff:ffff:ffff:ffff:ffff:ffff
187ff76:ec00:ba00::/40ff76:ec00:baff:ffff:ffff:ffff:ffff:ffff
188ff76:ec00:bb00::/40ff76:ec00:bbff:ffff:ffff:ffff:ffff:ffff
189ff76:ec00:bc00::/40ff76:ec00:bcff:ffff:ffff:ffff:ffff:ffff
190ff76:ec00:bd00::/40ff76:ec00:bdff:ffff:ffff:ffff:ffff:ffff
191ff76:ec00:be00::/40ff76:ec00:beff:ffff:ffff:ffff:ffff:ffff
192ff76:ec00:bf00::/40ff76:ec00:bfff:ffff:ffff:ffff:ffff:ffff
193ff76:ec00:c000::/40ff76:ec00:c0ff:ffff:ffff:ffff:ffff:ffff
194ff76:ec00:c100::/40ff76:ec00:c1ff:ffff:ffff:ffff:ffff:ffff
195ff76:ec00:c200::/40ff76:ec00:c2ff:ffff:ffff:ffff:ffff:ffff
196ff76:ec00:c300::/40ff76:ec00:c3ff:ffff:ffff:ffff:ffff:ffff
197ff76:ec00:c400::/40ff76:ec00:c4ff:ffff:ffff:ffff:ffff:ffff
198ff76:ec00:c500::/40ff76:ec00:c5ff:ffff:ffff:ffff:ffff:ffff
199ff76:ec00:c600::/40ff76:ec00:c6ff:ffff:ffff:ffff:ffff:ffff
200ff76:ec00:c700::/40ff76:ec00:c7ff:ffff:ffff:ffff:ffff:ffff
201ff76:ec00:c800::/40ff76:ec00:c8ff:ffff:ffff:ffff:ffff:ffff
202ff76:ec00:c900::/40ff76:ec00:c9ff:ffff:ffff:ffff:ffff:ffff
203ff76:ec00:ca00::/40ff76:ec00:caff:ffff:ffff:ffff:ffff:ffff
204ff76:ec00:cb00::/40ff76:ec00:cbff:ffff:ffff:ffff:ffff:ffff
205ff76:ec00:cc00::/40ff76:ec00:ccff:ffff:ffff:ffff:ffff:ffff
206ff76:ec00:cd00::/40ff76:ec00:cdff:ffff:ffff:ffff:ffff:ffff
207ff76:ec00:ce00::/40ff76:ec00:ceff:ffff:ffff:ffff:ffff:ffff
208ff76:ec00:cf00::/40ff76:ec00:cfff:ffff:ffff:ffff:ffff:ffff
209ff76:ec00:d000::/40ff76:ec00:d0ff:ffff:ffff:ffff:ffff:ffff
210ff76:ec00:d100::/40ff76:ec00:d1ff:ffff:ffff:ffff:ffff:ffff
211ff76:ec00:d200::/40ff76:ec00:d2ff:ffff:ffff:ffff:ffff:ffff
212ff76:ec00:d300::/40ff76:ec00:d3ff:ffff:ffff:ffff:ffff:ffff
213ff76:ec00:d400::/40ff76:ec00:d4ff:ffff:ffff:ffff:ffff:ffff
214ff76:ec00:d500::/40ff76:ec00:d5ff:ffff:ffff:ffff:ffff:ffff
215ff76:ec00:d600::/40ff76:ec00:d6ff:ffff:ffff:ffff:ffff:ffff
216ff76:ec00:d700::/40ff76:ec00:d7ff:ffff:ffff:ffff:ffff:ffff
217ff76:ec00:d800::/40ff76:ec00:d8ff:ffff:ffff:ffff:ffff:ffff
218ff76:ec00:d900::/40ff76:ec00:d9ff:ffff:ffff:ffff:ffff:ffff
219ff76:ec00:da00::/40ff76:ec00:daff:ffff:ffff:ffff:ffff:ffff
220ff76:ec00:db00::/40ff76:ec00:dbff:ffff:ffff:ffff:ffff:ffff
221ff76:ec00:dc00::/40ff76:ec00:dcff:ffff:ffff:ffff:ffff:ffff
222ff76:ec00:dd00::/40ff76:ec00:ddff:ffff:ffff:ffff:ffff:ffff
223ff76:ec00:de00::/40ff76:ec00:deff:ffff:ffff:ffff:ffff:ffff
224ff76:ec00:df00::/40ff76:ec00:dfff:ffff:ffff:ffff:ffff:ffff
225ff76:ec00:e000::/40ff76:ec00:e0ff:ffff:ffff:ffff:ffff:ffff
226ff76:ec00:e100::/40ff76:ec00:e1ff:ffff:ffff:ffff:ffff:ffff
227ff76:ec00:e200::/40ff76:ec00:e2ff:ffff:ffff:ffff:ffff:ffff
228ff76:ec00:e300::/40ff76:ec00:e3ff:ffff:ffff:ffff:ffff:ffff
229ff76:ec00:e400::/40ff76:ec00:e4ff:ffff:ffff:ffff:ffff:ffff
230ff76:ec00:e500::/40ff76:ec00:e5ff:ffff:ffff:ffff:ffff:ffff
231ff76:ec00:e600::/40ff76:ec00:e6ff:ffff:ffff:ffff:ffff:ffff
232ff76:ec00:e700::/40ff76:ec00:e7ff:ffff:ffff:ffff:ffff:ffff
233ff76:ec00:e800::/40ff76:ec00:e8ff:ffff:ffff:ffff:ffff:ffff
234ff76:ec00:e900::/40ff76:ec00:e9ff:ffff:ffff:ffff:ffff:ffff
235ff76:ec00:ea00::/40ff76:ec00:eaff:ffff:ffff:ffff:ffff:ffff
236ff76:ec00:eb00::/40ff76:ec00:ebff:ffff:ffff:ffff:ffff:ffff
237ff76:ec00:ec00::/40ff76:ec00:ecff:ffff:ffff:ffff:ffff:ffff
238ff76:ec00:ed00::/40ff76:ec00:edff:ffff:ffff:ffff:ffff:ffff
239ff76:ec00:ee00::/40ff76:ec00:eeff:ffff:ffff:ffff:ffff:ffff
240ff76:ec00:ef00::/40ff76:ec00:efff:ffff:ffff:ffff:ffff:ffff
241ff76:ec00:f000::/40ff76:ec00:f0ff:ffff:ffff:ffff:ffff:ffff
242ff76:ec00:f100::/40ff76:ec00:f1ff:ffff:ffff:ffff:ffff:ffff
243ff76:ec00:f200::/40ff76:ec00:f2ff:ffff:ffff:ffff:ffff:ffff
244ff76:ec00:f300::/40ff76:ec00:f3ff:ffff:ffff:ffff:ffff:ffff
245ff76:ec00:f400::/40ff76:ec00:f4ff:ffff:ffff:ffff:ffff:ffff
246ff76:ec00:f500::/40ff76:ec00:f5ff:ffff:ffff:ffff:ffff:ffff
247ff76:ec00:f600::/40ff76:ec00:f6ff:ffff:ffff:ffff:ffff:ffff
248ff76:ec00:f700::/40ff76:ec00:f7ff:ffff:ffff:ffff:ffff:ffff
249ff76:ec00:f800::/40ff76:ec00:f8ff:ffff:ffff:ffff:ffff:ffff
250ff76:ec00:f900::/40ff76:ec00:f9ff:ffff:ffff:ffff:ffff:ffff
251ff76:ec00:fa00::/40ff76:ec00:faff:ffff:ffff:ffff:ffff:ffff
252ff76:ec00:fb00::/40ff76:ec00:fbff:ffff:ffff:ffff:ffff:ffff
253ff76:ec00:fc00::/40ff76:ec00:fcff:ffff:ffff:ffff:ffff:ffff
254ff76:ec00:fd00::/40ff76:ec00:fdff:ffff:ffff:ffff:ffff:ffff
255ff76:ec00:fe00::/40ff76:ec00:feff:ffff:ffff:ffff:ffff:ffff
256ff76:ec00:ff00::/40ff76:ec00: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.