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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
ff67::/16
First address
ff67::
Last address
ff67: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
ff67:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
7.6.f.f.ip6.arpa
Split into smaller subnets/28
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

ff67::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
1ff67::/28ff67:f:ffff:ffff:ffff:ffff:ffff:ffff
2ff67:10::/28ff67:1f:ffff:ffff:ffff:ffff:ffff:ffff
3ff67:20::/28ff67:2f:ffff:ffff:ffff:ffff:ffff:ffff
4ff67:30::/28ff67:3f:ffff:ffff:ffff:ffff:ffff:ffff
5ff67:40::/28ff67:4f:ffff:ffff:ffff:ffff:ffff:ffff
6ff67:50::/28ff67:5f:ffff:ffff:ffff:ffff:ffff:ffff
7ff67:60::/28ff67:6f:ffff:ffff:ffff:ffff:ffff:ffff
8ff67:70::/28ff67:7f:ffff:ffff:ffff:ffff:ffff:ffff
9ff67:80::/28ff67:8f:ffff:ffff:ffff:ffff:ffff:ffff
10ff67:90::/28ff67:9f:ffff:ffff:ffff:ffff:ffff:ffff
11ff67:a0::/28ff67:af:ffff:ffff:ffff:ffff:ffff:ffff
12ff67:b0::/28ff67:bf:ffff:ffff:ffff:ffff:ffff:ffff
13ff67:c0::/28ff67:cf:ffff:ffff:ffff:ffff:ffff:ffff
14ff67:d0::/28ff67:df:ffff:ffff:ffff:ffff:ffff:ffff
15ff67:e0::/28ff67:ef:ffff:ffff:ffff:ffff:ffff:ffff
16ff67:f0::/28ff67:ff:ffff:ffff:ffff:ffff:ffff:ffff
17ff67:100::/28ff67:10f:ffff:ffff:ffff:ffff:ffff:ffff
18ff67:110::/28ff67:11f:ffff:ffff:ffff:ffff:ffff:ffff
19ff67:120::/28ff67:12f:ffff:ffff:ffff:ffff:ffff:ffff
20ff67:130::/28ff67:13f:ffff:ffff:ffff:ffff:ffff:ffff
21ff67:140::/28ff67:14f:ffff:ffff:ffff:ffff:ffff:ffff
22ff67:150::/28ff67:15f:ffff:ffff:ffff:ffff:ffff:ffff
23ff67:160::/28ff67:16f:ffff:ffff:ffff:ffff:ffff:ffff
24ff67:170::/28ff67:17f:ffff:ffff:ffff:ffff:ffff:ffff
25ff67:180::/28ff67:18f:ffff:ffff:ffff:ffff:ffff:ffff
26ff67:190::/28ff67:19f:ffff:ffff:ffff:ffff:ffff:ffff
27ff67:1a0::/28ff67:1af:ffff:ffff:ffff:ffff:ffff:ffff
28ff67:1b0::/28ff67:1bf:ffff:ffff:ffff:ffff:ffff:ffff
29ff67:1c0::/28ff67:1cf:ffff:ffff:ffff:ffff:ffff:ffff
30ff67:1d0::/28ff67:1df:ffff:ffff:ffff:ffff:ffff:ffff
31ff67:1e0::/28ff67:1ef:ffff:ffff:ffff:ffff:ffff:ffff
32ff67:1f0::/28ff67:1ff:ffff:ffff:ffff:ffff:ffff:ffff
33ff67:200::/28ff67:20f:ffff:ffff:ffff:ffff:ffff:ffff
34ff67:210::/28ff67:21f:ffff:ffff:ffff:ffff:ffff:ffff
35ff67:220::/28ff67:22f:ffff:ffff:ffff:ffff:ffff:ffff
36ff67:230::/28ff67:23f:ffff:ffff:ffff:ffff:ffff:ffff
37ff67:240::/28ff67:24f:ffff:ffff:ffff:ffff:ffff:ffff
38ff67:250::/28ff67:25f:ffff:ffff:ffff:ffff:ffff:ffff
39ff67:260::/28ff67:26f:ffff:ffff:ffff:ffff:ffff:ffff
40ff67:270::/28ff67:27f:ffff:ffff:ffff:ffff:ffff:ffff
41ff67:280::/28ff67:28f:ffff:ffff:ffff:ffff:ffff:ffff
42ff67:290::/28ff67:29f:ffff:ffff:ffff:ffff:ffff:ffff
43ff67:2a0::/28ff67:2af:ffff:ffff:ffff:ffff:ffff:ffff
44ff67:2b0::/28ff67:2bf:ffff:ffff:ffff:ffff:ffff:ffff
45ff67:2c0::/28ff67:2cf:ffff:ffff:ffff:ffff:ffff:ffff
46ff67:2d0::/28ff67:2df:ffff:ffff:ffff:ffff:ffff:ffff
47ff67:2e0::/28ff67:2ef:ffff:ffff:ffff:ffff:ffff:ffff
48ff67:2f0::/28ff67:2ff:ffff:ffff:ffff:ffff:ffff:ffff
49ff67:300::/28ff67:30f:ffff:ffff:ffff:ffff:ffff:ffff
50ff67:310::/28ff67:31f:ffff:ffff:ffff:ffff:ffff:ffff
51ff67:320::/28ff67:32f:ffff:ffff:ffff:ffff:ffff:ffff
52ff67:330::/28ff67:33f:ffff:ffff:ffff:ffff:ffff:ffff
53ff67:340::/28ff67:34f:ffff:ffff:ffff:ffff:ffff:ffff
54ff67:350::/28ff67:35f:ffff:ffff:ffff:ffff:ffff:ffff
55ff67:360::/28ff67:36f:ffff:ffff:ffff:ffff:ffff:ffff
56ff67:370::/28ff67:37f:ffff:ffff:ffff:ffff:ffff:ffff
57ff67:380::/28ff67:38f:ffff:ffff:ffff:ffff:ffff:ffff
58ff67:390::/28ff67:39f:ffff:ffff:ffff:ffff:ffff:ffff
59ff67:3a0::/28ff67:3af:ffff:ffff:ffff:ffff:ffff:ffff
60ff67:3b0::/28ff67:3bf:ffff:ffff:ffff:ffff:ffff:ffff
61ff67:3c0::/28ff67:3cf:ffff:ffff:ffff:ffff:ffff:ffff
62ff67:3d0::/28ff67:3df:ffff:ffff:ffff:ffff:ffff:ffff
63ff67:3e0::/28ff67:3ef:ffff:ffff:ffff:ffff:ffff:ffff
64ff67:3f0::/28ff67:3ff:ffff:ffff:ffff:ffff:ffff:ffff
65ff67:400::/28ff67:40f:ffff:ffff:ffff:ffff:ffff:ffff
66ff67:410::/28ff67:41f:ffff:ffff:ffff:ffff:ffff:ffff
67ff67:420::/28ff67:42f:ffff:ffff:ffff:ffff:ffff:ffff
68ff67:430::/28ff67:43f:ffff:ffff:ffff:ffff:ffff:ffff
69ff67:440::/28ff67:44f:ffff:ffff:ffff:ffff:ffff:ffff
70ff67:450::/28ff67:45f:ffff:ffff:ffff:ffff:ffff:ffff
71ff67:460::/28ff67:46f:ffff:ffff:ffff:ffff:ffff:ffff
72ff67:470::/28ff67:47f:ffff:ffff:ffff:ffff:ffff:ffff
73ff67:480::/28ff67:48f:ffff:ffff:ffff:ffff:ffff:ffff
74ff67:490::/28ff67:49f:ffff:ffff:ffff:ffff:ffff:ffff
75ff67:4a0::/28ff67:4af:ffff:ffff:ffff:ffff:ffff:ffff
76ff67:4b0::/28ff67:4bf:ffff:ffff:ffff:ffff:ffff:ffff
77ff67:4c0::/28ff67:4cf:ffff:ffff:ffff:ffff:ffff:ffff
78ff67:4d0::/28ff67:4df:ffff:ffff:ffff:ffff:ffff:ffff
79ff67:4e0::/28ff67:4ef:ffff:ffff:ffff:ffff:ffff:ffff
80ff67:4f0::/28ff67:4ff:ffff:ffff:ffff:ffff:ffff:ffff
81ff67:500::/28ff67:50f:ffff:ffff:ffff:ffff:ffff:ffff
82ff67:510::/28ff67:51f:ffff:ffff:ffff:ffff:ffff:ffff
83ff67:520::/28ff67:52f:ffff:ffff:ffff:ffff:ffff:ffff
84ff67:530::/28ff67:53f:ffff:ffff:ffff:ffff:ffff:ffff
85ff67:540::/28ff67:54f:ffff:ffff:ffff:ffff:ffff:ffff
86ff67:550::/28ff67:55f:ffff:ffff:ffff:ffff:ffff:ffff
87ff67:560::/28ff67:56f:ffff:ffff:ffff:ffff:ffff:ffff
88ff67:570::/28ff67:57f:ffff:ffff:ffff:ffff:ffff:ffff
89ff67:580::/28ff67:58f:ffff:ffff:ffff:ffff:ffff:ffff
90ff67:590::/28ff67:59f:ffff:ffff:ffff:ffff:ffff:ffff
91ff67:5a0::/28ff67:5af:ffff:ffff:ffff:ffff:ffff:ffff
92ff67:5b0::/28ff67:5bf:ffff:ffff:ffff:ffff:ffff:ffff
93ff67:5c0::/28ff67:5cf:ffff:ffff:ffff:ffff:ffff:ffff
94ff67:5d0::/28ff67:5df:ffff:ffff:ffff:ffff:ffff:ffff
95ff67:5e0::/28ff67:5ef:ffff:ffff:ffff:ffff:ffff:ffff
96ff67:5f0::/28ff67:5ff:ffff:ffff:ffff:ffff:ffff:ffff
97ff67:600::/28ff67:60f:ffff:ffff:ffff:ffff:ffff:ffff
98ff67:610::/28ff67:61f:ffff:ffff:ffff:ffff:ffff:ffff
99ff67:620::/28ff67:62f:ffff:ffff:ffff:ffff:ffff:ffff
100ff67:630::/28ff67:63f:ffff:ffff:ffff:ffff:ffff:ffff
101ff67:640::/28ff67:64f:ffff:ffff:ffff:ffff:ffff:ffff
102ff67:650::/28ff67:65f:ffff:ffff:ffff:ffff:ffff:ffff
103ff67:660::/28ff67:66f:ffff:ffff:ffff:ffff:ffff:ffff
104ff67:670::/28ff67:67f:ffff:ffff:ffff:ffff:ffff:ffff
105ff67:680::/28ff67:68f:ffff:ffff:ffff:ffff:ffff:ffff
106ff67:690::/28ff67:69f:ffff:ffff:ffff:ffff:ffff:ffff
107ff67:6a0::/28ff67:6af:ffff:ffff:ffff:ffff:ffff:ffff
108ff67:6b0::/28ff67:6bf:ffff:ffff:ffff:ffff:ffff:ffff
109ff67:6c0::/28ff67:6cf:ffff:ffff:ffff:ffff:ffff:ffff
110ff67:6d0::/28ff67:6df:ffff:ffff:ffff:ffff:ffff:ffff
111ff67:6e0::/28ff67:6ef:ffff:ffff:ffff:ffff:ffff:ffff
112ff67:6f0::/28ff67:6ff:ffff:ffff:ffff:ffff:ffff:ffff
113ff67:700::/28ff67:70f:ffff:ffff:ffff:ffff:ffff:ffff
114ff67:710::/28ff67:71f:ffff:ffff:ffff:ffff:ffff:ffff
115ff67:720::/28ff67:72f:ffff:ffff:ffff:ffff:ffff:ffff
116ff67:730::/28ff67:73f:ffff:ffff:ffff:ffff:ffff:ffff
117ff67:740::/28ff67:74f:ffff:ffff:ffff:ffff:ffff:ffff
118ff67:750::/28ff67:75f:ffff:ffff:ffff:ffff:ffff:ffff
119ff67:760::/28ff67:76f:ffff:ffff:ffff:ffff:ffff:ffff
120ff67:770::/28ff67:77f:ffff:ffff:ffff:ffff:ffff:ffff
121ff67:780::/28ff67:78f:ffff:ffff:ffff:ffff:ffff:ffff
122ff67:790::/28ff67:79f:ffff:ffff:ffff:ffff:ffff:ffff
123ff67:7a0::/28ff67:7af:ffff:ffff:ffff:ffff:ffff:ffff
124ff67:7b0::/28ff67:7bf:ffff:ffff:ffff:ffff:ffff:ffff
125ff67:7c0::/28ff67:7cf:ffff:ffff:ffff:ffff:ffff:ffff
126ff67:7d0::/28ff67:7df:ffff:ffff:ffff:ffff:ffff:ffff
127ff67:7e0::/28ff67:7ef:ffff:ffff:ffff:ffff:ffff:ffff
128ff67:7f0::/28ff67:7ff:ffff:ffff:ffff:ffff:ffff:ffff
129ff67:800::/28ff67:80f:ffff:ffff:ffff:ffff:ffff:ffff
130ff67:810::/28ff67:81f:ffff:ffff:ffff:ffff:ffff:ffff
131ff67:820::/28ff67:82f:ffff:ffff:ffff:ffff:ffff:ffff
132ff67:830::/28ff67:83f:ffff:ffff:ffff:ffff:ffff:ffff
133ff67:840::/28ff67:84f:ffff:ffff:ffff:ffff:ffff:ffff
134ff67:850::/28ff67:85f:ffff:ffff:ffff:ffff:ffff:ffff
135ff67:860::/28ff67:86f:ffff:ffff:ffff:ffff:ffff:ffff
136ff67:870::/28ff67:87f:ffff:ffff:ffff:ffff:ffff:ffff
137ff67:880::/28ff67:88f:ffff:ffff:ffff:ffff:ffff:ffff
138ff67:890::/28ff67:89f:ffff:ffff:ffff:ffff:ffff:ffff
139ff67:8a0::/28ff67:8af:ffff:ffff:ffff:ffff:ffff:ffff
140ff67:8b0::/28ff67:8bf:ffff:ffff:ffff:ffff:ffff:ffff
141ff67:8c0::/28ff67:8cf:ffff:ffff:ffff:ffff:ffff:ffff
142ff67:8d0::/28ff67:8df:ffff:ffff:ffff:ffff:ffff:ffff
143ff67:8e0::/28ff67:8ef:ffff:ffff:ffff:ffff:ffff:ffff
144ff67:8f0::/28ff67:8ff:ffff:ffff:ffff:ffff:ffff:ffff
145ff67:900::/28ff67:90f:ffff:ffff:ffff:ffff:ffff:ffff
146ff67:910::/28ff67:91f:ffff:ffff:ffff:ffff:ffff:ffff
147ff67:920::/28ff67:92f:ffff:ffff:ffff:ffff:ffff:ffff
148ff67:930::/28ff67:93f:ffff:ffff:ffff:ffff:ffff:ffff
149ff67:940::/28ff67:94f:ffff:ffff:ffff:ffff:ffff:ffff
150ff67:950::/28ff67:95f:ffff:ffff:ffff:ffff:ffff:ffff
151ff67:960::/28ff67:96f:ffff:ffff:ffff:ffff:ffff:ffff
152ff67:970::/28ff67:97f:ffff:ffff:ffff:ffff:ffff:ffff
153ff67:980::/28ff67:98f:ffff:ffff:ffff:ffff:ffff:ffff
154ff67:990::/28ff67:99f:ffff:ffff:ffff:ffff:ffff:ffff
155ff67:9a0::/28ff67:9af:ffff:ffff:ffff:ffff:ffff:ffff
156ff67:9b0::/28ff67:9bf:ffff:ffff:ffff:ffff:ffff:ffff
157ff67:9c0::/28ff67:9cf:ffff:ffff:ffff:ffff:ffff:ffff
158ff67:9d0::/28ff67:9df:ffff:ffff:ffff:ffff:ffff:ffff
159ff67:9e0::/28ff67:9ef:ffff:ffff:ffff:ffff:ffff:ffff
160ff67:9f0::/28ff67:9ff:ffff:ffff:ffff:ffff:ffff:ffff
161ff67:a00::/28ff67:a0f:ffff:ffff:ffff:ffff:ffff:ffff
162ff67:a10::/28ff67:a1f:ffff:ffff:ffff:ffff:ffff:ffff
163ff67:a20::/28ff67:a2f:ffff:ffff:ffff:ffff:ffff:ffff
164ff67:a30::/28ff67:a3f:ffff:ffff:ffff:ffff:ffff:ffff
165ff67:a40::/28ff67:a4f:ffff:ffff:ffff:ffff:ffff:ffff
166ff67:a50::/28ff67:a5f:ffff:ffff:ffff:ffff:ffff:ffff
167ff67:a60::/28ff67:a6f:ffff:ffff:ffff:ffff:ffff:ffff
168ff67:a70::/28ff67:a7f:ffff:ffff:ffff:ffff:ffff:ffff
169ff67:a80::/28ff67:a8f:ffff:ffff:ffff:ffff:ffff:ffff
170ff67:a90::/28ff67:a9f:ffff:ffff:ffff:ffff:ffff:ffff
171ff67:aa0::/28ff67:aaf:ffff:ffff:ffff:ffff:ffff:ffff
172ff67:ab0::/28ff67:abf:ffff:ffff:ffff:ffff:ffff:ffff
173ff67:ac0::/28ff67:acf:ffff:ffff:ffff:ffff:ffff:ffff
174ff67:ad0::/28ff67:adf:ffff:ffff:ffff:ffff:ffff:ffff
175ff67:ae0::/28ff67:aef:ffff:ffff:ffff:ffff:ffff:ffff
176ff67:af0::/28ff67:aff:ffff:ffff:ffff:ffff:ffff:ffff
177ff67:b00::/28ff67:b0f:ffff:ffff:ffff:ffff:ffff:ffff
178ff67:b10::/28ff67:b1f:ffff:ffff:ffff:ffff:ffff:ffff
179ff67:b20::/28ff67:b2f:ffff:ffff:ffff:ffff:ffff:ffff
180ff67:b30::/28ff67:b3f:ffff:ffff:ffff:ffff:ffff:ffff
181ff67:b40::/28ff67:b4f:ffff:ffff:ffff:ffff:ffff:ffff
182ff67:b50::/28ff67:b5f:ffff:ffff:ffff:ffff:ffff:ffff
183ff67:b60::/28ff67:b6f:ffff:ffff:ffff:ffff:ffff:ffff
184ff67:b70::/28ff67:b7f:ffff:ffff:ffff:ffff:ffff:ffff
185ff67:b80::/28ff67:b8f:ffff:ffff:ffff:ffff:ffff:ffff
186ff67:b90::/28ff67:b9f:ffff:ffff:ffff:ffff:ffff:ffff
187ff67:ba0::/28ff67:baf:ffff:ffff:ffff:ffff:ffff:ffff
188ff67:bb0::/28ff67:bbf:ffff:ffff:ffff:ffff:ffff:ffff
189ff67:bc0::/28ff67:bcf:ffff:ffff:ffff:ffff:ffff:ffff
190ff67:bd0::/28ff67:bdf:ffff:ffff:ffff:ffff:ffff:ffff
191ff67:be0::/28ff67:bef:ffff:ffff:ffff:ffff:ffff:ffff
192ff67:bf0::/28ff67:bff:ffff:ffff:ffff:ffff:ffff:ffff
193ff67:c00::/28ff67:c0f:ffff:ffff:ffff:ffff:ffff:ffff
194ff67:c10::/28ff67:c1f:ffff:ffff:ffff:ffff:ffff:ffff
195ff67:c20::/28ff67:c2f:ffff:ffff:ffff:ffff:ffff:ffff
196ff67:c30::/28ff67:c3f:ffff:ffff:ffff:ffff:ffff:ffff
197ff67:c40::/28ff67:c4f:ffff:ffff:ffff:ffff:ffff:ffff
198ff67:c50::/28ff67:c5f:ffff:ffff:ffff:ffff:ffff:ffff
199ff67:c60::/28ff67:c6f:ffff:ffff:ffff:ffff:ffff:ffff
200ff67:c70::/28ff67:c7f:ffff:ffff:ffff:ffff:ffff:ffff
201ff67:c80::/28ff67:c8f:ffff:ffff:ffff:ffff:ffff:ffff
202ff67:c90::/28ff67:c9f:ffff:ffff:ffff:ffff:ffff:ffff
203ff67:ca0::/28ff67:caf:ffff:ffff:ffff:ffff:ffff:ffff
204ff67:cb0::/28ff67:cbf:ffff:ffff:ffff:ffff:ffff:ffff
205ff67:cc0::/28ff67:ccf:ffff:ffff:ffff:ffff:ffff:ffff
206ff67:cd0::/28ff67:cdf:ffff:ffff:ffff:ffff:ffff:ffff
207ff67:ce0::/28ff67:cef:ffff:ffff:ffff:ffff:ffff:ffff
208ff67:cf0::/28ff67:cff:ffff:ffff:ffff:ffff:ffff:ffff
209ff67:d00::/28ff67:d0f:ffff:ffff:ffff:ffff:ffff:ffff
210ff67:d10::/28ff67:d1f:ffff:ffff:ffff:ffff:ffff:ffff
211ff67:d20::/28ff67:d2f:ffff:ffff:ffff:ffff:ffff:ffff
212ff67:d30::/28ff67:d3f:ffff:ffff:ffff:ffff:ffff:ffff
213ff67:d40::/28ff67:d4f:ffff:ffff:ffff:ffff:ffff:ffff
214ff67:d50::/28ff67:d5f:ffff:ffff:ffff:ffff:ffff:ffff
215ff67:d60::/28ff67:d6f:ffff:ffff:ffff:ffff:ffff:ffff
216ff67:d70::/28ff67:d7f:ffff:ffff:ffff:ffff:ffff:ffff
217ff67:d80::/28ff67:d8f:ffff:ffff:ffff:ffff:ffff:ffff
218ff67:d90::/28ff67:d9f:ffff:ffff:ffff:ffff:ffff:ffff
219ff67:da0::/28ff67:daf:ffff:ffff:ffff:ffff:ffff:ffff
220ff67:db0::/28ff67:dbf:ffff:ffff:ffff:ffff:ffff:ffff
221ff67:dc0::/28ff67:dcf:ffff:ffff:ffff:ffff:ffff:ffff
222ff67:dd0::/28ff67:ddf:ffff:ffff:ffff:ffff:ffff:ffff
223ff67:de0::/28ff67:def:ffff:ffff:ffff:ffff:ffff:ffff
224ff67:df0::/28ff67:dff:ffff:ffff:ffff:ffff:ffff:ffff
225ff67:e00::/28ff67:e0f:ffff:ffff:ffff:ffff:ffff:ffff
226ff67:e10::/28ff67:e1f:ffff:ffff:ffff:ffff:ffff:ffff
227ff67:e20::/28ff67:e2f:ffff:ffff:ffff:ffff:ffff:ffff
228ff67:e30::/28ff67:e3f:ffff:ffff:ffff:ffff:ffff:ffff
229ff67:e40::/28ff67:e4f:ffff:ffff:ffff:ffff:ffff:ffff
230ff67:e50::/28ff67:e5f:ffff:ffff:ffff:ffff:ffff:ffff
231ff67:e60::/28ff67:e6f:ffff:ffff:ffff:ffff:ffff:ffff
232ff67:e70::/28ff67:e7f:ffff:ffff:ffff:ffff:ffff:ffff
233ff67:e80::/28ff67:e8f:ffff:ffff:ffff:ffff:ffff:ffff
234ff67:e90::/28ff67:e9f:ffff:ffff:ffff:ffff:ffff:ffff
235ff67:ea0::/28ff67:eaf:ffff:ffff:ffff:ffff:ffff:ffff
236ff67:eb0::/28ff67:ebf:ffff:ffff:ffff:ffff:ffff:ffff
237ff67:ec0::/28ff67:ecf:ffff:ffff:ffff:ffff:ffff:ffff
238ff67:ed0::/28ff67:edf:ffff:ffff:ffff:ffff:ffff:ffff
239ff67:ee0::/28ff67:eef:ffff:ffff:ffff:ffff:ffff:ffff
240ff67:ef0::/28ff67:eff:ffff:ffff:ffff:ffff:ffff:ffff
241ff67:f00::/28ff67:f0f:ffff:ffff:ffff:ffff:ffff:ffff
242ff67:f10::/28ff67:f1f:ffff:ffff:ffff:ffff:ffff:ffff
243ff67:f20::/28ff67:f2f:ffff:ffff:ffff:ffff:ffff:ffff
244ff67:f30::/28ff67:f3f:ffff:ffff:ffff:ffff:ffff:ffff
245ff67:f40::/28ff67:f4f:ffff:ffff:ffff:ffff:ffff:ffff
246ff67:f50::/28ff67:f5f:ffff:ffff:ffff:ffff:ffff:ffff
247ff67:f60::/28ff67:f6f:ffff:ffff:ffff:ffff:ffff:ffff
248ff67:f70::/28ff67:f7f:ffff:ffff:ffff:ffff:ffff:ffff
249ff67:f80::/28ff67:f8f:ffff:ffff:ffff:ffff:ffff:ffff
250ff67:f90::/28ff67:f9f:ffff:ffff:ffff:ffff:ffff:ffff
251ff67:fa0::/28ff67:faf:ffff:ffff:ffff:ffff:ffff:ffff
252ff67:fb0::/28ff67:fbf:ffff:ffff:ffff:ffff:ffff:ffff
253ff67:fc0::/28ff67:fcf:ffff:ffff:ffff:ffff:ffff:ffff
254ff67:fd0::/28ff67:fdf:ffff:ffff:ffff:ffff:ffff:ffff
255ff67:fe0::/28ff67:fef:ffff:ffff:ffff:ffff:ffff:ffff
256ff67:ff0::/28ff67:fff: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.