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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
ff24::/16
First address
ff24::
Last address
ff24: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
ff24:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
4.2.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)

ff24::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
1ff24::/28ff24:f:ffff:ffff:ffff:ffff:ffff:ffff
2ff24:10::/28ff24:1f:ffff:ffff:ffff:ffff:ffff:ffff
3ff24:20::/28ff24:2f:ffff:ffff:ffff:ffff:ffff:ffff
4ff24:30::/28ff24:3f:ffff:ffff:ffff:ffff:ffff:ffff
5ff24:40::/28ff24:4f:ffff:ffff:ffff:ffff:ffff:ffff
6ff24:50::/28ff24:5f:ffff:ffff:ffff:ffff:ffff:ffff
7ff24:60::/28ff24:6f:ffff:ffff:ffff:ffff:ffff:ffff
8ff24:70::/28ff24:7f:ffff:ffff:ffff:ffff:ffff:ffff
9ff24:80::/28ff24:8f:ffff:ffff:ffff:ffff:ffff:ffff
10ff24:90::/28ff24:9f:ffff:ffff:ffff:ffff:ffff:ffff
11ff24:a0::/28ff24:af:ffff:ffff:ffff:ffff:ffff:ffff
12ff24:b0::/28ff24:bf:ffff:ffff:ffff:ffff:ffff:ffff
13ff24:c0::/28ff24:cf:ffff:ffff:ffff:ffff:ffff:ffff
14ff24:d0::/28ff24:df:ffff:ffff:ffff:ffff:ffff:ffff
15ff24:e0::/28ff24:ef:ffff:ffff:ffff:ffff:ffff:ffff
16ff24:f0::/28ff24:ff:ffff:ffff:ffff:ffff:ffff:ffff
17ff24:100::/28ff24:10f:ffff:ffff:ffff:ffff:ffff:ffff
18ff24:110::/28ff24:11f:ffff:ffff:ffff:ffff:ffff:ffff
19ff24:120::/28ff24:12f:ffff:ffff:ffff:ffff:ffff:ffff
20ff24:130::/28ff24:13f:ffff:ffff:ffff:ffff:ffff:ffff
21ff24:140::/28ff24:14f:ffff:ffff:ffff:ffff:ffff:ffff
22ff24:150::/28ff24:15f:ffff:ffff:ffff:ffff:ffff:ffff
23ff24:160::/28ff24:16f:ffff:ffff:ffff:ffff:ffff:ffff
24ff24:170::/28ff24:17f:ffff:ffff:ffff:ffff:ffff:ffff
25ff24:180::/28ff24:18f:ffff:ffff:ffff:ffff:ffff:ffff
26ff24:190::/28ff24:19f:ffff:ffff:ffff:ffff:ffff:ffff
27ff24:1a0::/28ff24:1af:ffff:ffff:ffff:ffff:ffff:ffff
28ff24:1b0::/28ff24:1bf:ffff:ffff:ffff:ffff:ffff:ffff
29ff24:1c0::/28ff24:1cf:ffff:ffff:ffff:ffff:ffff:ffff
30ff24:1d0::/28ff24:1df:ffff:ffff:ffff:ffff:ffff:ffff
31ff24:1e0::/28ff24:1ef:ffff:ffff:ffff:ffff:ffff:ffff
32ff24:1f0::/28ff24:1ff:ffff:ffff:ffff:ffff:ffff:ffff
33ff24:200::/28ff24:20f:ffff:ffff:ffff:ffff:ffff:ffff
34ff24:210::/28ff24:21f:ffff:ffff:ffff:ffff:ffff:ffff
35ff24:220::/28ff24:22f:ffff:ffff:ffff:ffff:ffff:ffff
36ff24:230::/28ff24:23f:ffff:ffff:ffff:ffff:ffff:ffff
37ff24:240::/28ff24:24f:ffff:ffff:ffff:ffff:ffff:ffff
38ff24:250::/28ff24:25f:ffff:ffff:ffff:ffff:ffff:ffff
39ff24:260::/28ff24:26f:ffff:ffff:ffff:ffff:ffff:ffff
40ff24:270::/28ff24:27f:ffff:ffff:ffff:ffff:ffff:ffff
41ff24:280::/28ff24:28f:ffff:ffff:ffff:ffff:ffff:ffff
42ff24:290::/28ff24:29f:ffff:ffff:ffff:ffff:ffff:ffff
43ff24:2a0::/28ff24:2af:ffff:ffff:ffff:ffff:ffff:ffff
44ff24:2b0::/28ff24:2bf:ffff:ffff:ffff:ffff:ffff:ffff
45ff24:2c0::/28ff24:2cf:ffff:ffff:ffff:ffff:ffff:ffff
46ff24:2d0::/28ff24:2df:ffff:ffff:ffff:ffff:ffff:ffff
47ff24:2e0::/28ff24:2ef:ffff:ffff:ffff:ffff:ffff:ffff
48ff24:2f0::/28ff24:2ff:ffff:ffff:ffff:ffff:ffff:ffff
49ff24:300::/28ff24:30f:ffff:ffff:ffff:ffff:ffff:ffff
50ff24:310::/28ff24:31f:ffff:ffff:ffff:ffff:ffff:ffff
51ff24:320::/28ff24:32f:ffff:ffff:ffff:ffff:ffff:ffff
52ff24:330::/28ff24:33f:ffff:ffff:ffff:ffff:ffff:ffff
53ff24:340::/28ff24:34f:ffff:ffff:ffff:ffff:ffff:ffff
54ff24:350::/28ff24:35f:ffff:ffff:ffff:ffff:ffff:ffff
55ff24:360::/28ff24:36f:ffff:ffff:ffff:ffff:ffff:ffff
56ff24:370::/28ff24:37f:ffff:ffff:ffff:ffff:ffff:ffff
57ff24:380::/28ff24:38f:ffff:ffff:ffff:ffff:ffff:ffff
58ff24:390::/28ff24:39f:ffff:ffff:ffff:ffff:ffff:ffff
59ff24:3a0::/28ff24:3af:ffff:ffff:ffff:ffff:ffff:ffff
60ff24:3b0::/28ff24:3bf:ffff:ffff:ffff:ffff:ffff:ffff
61ff24:3c0::/28ff24:3cf:ffff:ffff:ffff:ffff:ffff:ffff
62ff24:3d0::/28ff24:3df:ffff:ffff:ffff:ffff:ffff:ffff
63ff24:3e0::/28ff24:3ef:ffff:ffff:ffff:ffff:ffff:ffff
64ff24:3f0::/28ff24:3ff:ffff:ffff:ffff:ffff:ffff:ffff
65ff24:400::/28ff24:40f:ffff:ffff:ffff:ffff:ffff:ffff
66ff24:410::/28ff24:41f:ffff:ffff:ffff:ffff:ffff:ffff
67ff24:420::/28ff24:42f:ffff:ffff:ffff:ffff:ffff:ffff
68ff24:430::/28ff24:43f:ffff:ffff:ffff:ffff:ffff:ffff
69ff24:440::/28ff24:44f:ffff:ffff:ffff:ffff:ffff:ffff
70ff24:450::/28ff24:45f:ffff:ffff:ffff:ffff:ffff:ffff
71ff24:460::/28ff24:46f:ffff:ffff:ffff:ffff:ffff:ffff
72ff24:470::/28ff24:47f:ffff:ffff:ffff:ffff:ffff:ffff
73ff24:480::/28ff24:48f:ffff:ffff:ffff:ffff:ffff:ffff
74ff24:490::/28ff24:49f:ffff:ffff:ffff:ffff:ffff:ffff
75ff24:4a0::/28ff24:4af:ffff:ffff:ffff:ffff:ffff:ffff
76ff24:4b0::/28ff24:4bf:ffff:ffff:ffff:ffff:ffff:ffff
77ff24:4c0::/28ff24:4cf:ffff:ffff:ffff:ffff:ffff:ffff
78ff24:4d0::/28ff24:4df:ffff:ffff:ffff:ffff:ffff:ffff
79ff24:4e0::/28ff24:4ef:ffff:ffff:ffff:ffff:ffff:ffff
80ff24:4f0::/28ff24:4ff:ffff:ffff:ffff:ffff:ffff:ffff
81ff24:500::/28ff24:50f:ffff:ffff:ffff:ffff:ffff:ffff
82ff24:510::/28ff24:51f:ffff:ffff:ffff:ffff:ffff:ffff
83ff24:520::/28ff24:52f:ffff:ffff:ffff:ffff:ffff:ffff
84ff24:530::/28ff24:53f:ffff:ffff:ffff:ffff:ffff:ffff
85ff24:540::/28ff24:54f:ffff:ffff:ffff:ffff:ffff:ffff
86ff24:550::/28ff24:55f:ffff:ffff:ffff:ffff:ffff:ffff
87ff24:560::/28ff24:56f:ffff:ffff:ffff:ffff:ffff:ffff
88ff24:570::/28ff24:57f:ffff:ffff:ffff:ffff:ffff:ffff
89ff24:580::/28ff24:58f:ffff:ffff:ffff:ffff:ffff:ffff
90ff24:590::/28ff24:59f:ffff:ffff:ffff:ffff:ffff:ffff
91ff24:5a0::/28ff24:5af:ffff:ffff:ffff:ffff:ffff:ffff
92ff24:5b0::/28ff24:5bf:ffff:ffff:ffff:ffff:ffff:ffff
93ff24:5c0::/28ff24:5cf:ffff:ffff:ffff:ffff:ffff:ffff
94ff24:5d0::/28ff24:5df:ffff:ffff:ffff:ffff:ffff:ffff
95ff24:5e0::/28ff24:5ef:ffff:ffff:ffff:ffff:ffff:ffff
96ff24:5f0::/28ff24:5ff:ffff:ffff:ffff:ffff:ffff:ffff
97ff24:600::/28ff24:60f:ffff:ffff:ffff:ffff:ffff:ffff
98ff24:610::/28ff24:61f:ffff:ffff:ffff:ffff:ffff:ffff
99ff24:620::/28ff24:62f:ffff:ffff:ffff:ffff:ffff:ffff
100ff24:630::/28ff24:63f:ffff:ffff:ffff:ffff:ffff:ffff
101ff24:640::/28ff24:64f:ffff:ffff:ffff:ffff:ffff:ffff
102ff24:650::/28ff24:65f:ffff:ffff:ffff:ffff:ffff:ffff
103ff24:660::/28ff24:66f:ffff:ffff:ffff:ffff:ffff:ffff
104ff24:670::/28ff24:67f:ffff:ffff:ffff:ffff:ffff:ffff
105ff24:680::/28ff24:68f:ffff:ffff:ffff:ffff:ffff:ffff
106ff24:690::/28ff24:69f:ffff:ffff:ffff:ffff:ffff:ffff
107ff24:6a0::/28ff24:6af:ffff:ffff:ffff:ffff:ffff:ffff
108ff24:6b0::/28ff24:6bf:ffff:ffff:ffff:ffff:ffff:ffff
109ff24:6c0::/28ff24:6cf:ffff:ffff:ffff:ffff:ffff:ffff
110ff24:6d0::/28ff24:6df:ffff:ffff:ffff:ffff:ffff:ffff
111ff24:6e0::/28ff24:6ef:ffff:ffff:ffff:ffff:ffff:ffff
112ff24:6f0::/28ff24:6ff:ffff:ffff:ffff:ffff:ffff:ffff
113ff24:700::/28ff24:70f:ffff:ffff:ffff:ffff:ffff:ffff
114ff24:710::/28ff24:71f:ffff:ffff:ffff:ffff:ffff:ffff
115ff24:720::/28ff24:72f:ffff:ffff:ffff:ffff:ffff:ffff
116ff24:730::/28ff24:73f:ffff:ffff:ffff:ffff:ffff:ffff
117ff24:740::/28ff24:74f:ffff:ffff:ffff:ffff:ffff:ffff
118ff24:750::/28ff24:75f:ffff:ffff:ffff:ffff:ffff:ffff
119ff24:760::/28ff24:76f:ffff:ffff:ffff:ffff:ffff:ffff
120ff24:770::/28ff24:77f:ffff:ffff:ffff:ffff:ffff:ffff
121ff24:780::/28ff24:78f:ffff:ffff:ffff:ffff:ffff:ffff
122ff24:790::/28ff24:79f:ffff:ffff:ffff:ffff:ffff:ffff
123ff24:7a0::/28ff24:7af:ffff:ffff:ffff:ffff:ffff:ffff
124ff24:7b0::/28ff24:7bf:ffff:ffff:ffff:ffff:ffff:ffff
125ff24:7c0::/28ff24:7cf:ffff:ffff:ffff:ffff:ffff:ffff
126ff24:7d0::/28ff24:7df:ffff:ffff:ffff:ffff:ffff:ffff
127ff24:7e0::/28ff24:7ef:ffff:ffff:ffff:ffff:ffff:ffff
128ff24:7f0::/28ff24:7ff:ffff:ffff:ffff:ffff:ffff:ffff
129ff24:800::/28ff24:80f:ffff:ffff:ffff:ffff:ffff:ffff
130ff24:810::/28ff24:81f:ffff:ffff:ffff:ffff:ffff:ffff
131ff24:820::/28ff24:82f:ffff:ffff:ffff:ffff:ffff:ffff
132ff24:830::/28ff24:83f:ffff:ffff:ffff:ffff:ffff:ffff
133ff24:840::/28ff24:84f:ffff:ffff:ffff:ffff:ffff:ffff
134ff24:850::/28ff24:85f:ffff:ffff:ffff:ffff:ffff:ffff
135ff24:860::/28ff24:86f:ffff:ffff:ffff:ffff:ffff:ffff
136ff24:870::/28ff24:87f:ffff:ffff:ffff:ffff:ffff:ffff
137ff24:880::/28ff24:88f:ffff:ffff:ffff:ffff:ffff:ffff
138ff24:890::/28ff24:89f:ffff:ffff:ffff:ffff:ffff:ffff
139ff24:8a0::/28ff24:8af:ffff:ffff:ffff:ffff:ffff:ffff
140ff24:8b0::/28ff24:8bf:ffff:ffff:ffff:ffff:ffff:ffff
141ff24:8c0::/28ff24:8cf:ffff:ffff:ffff:ffff:ffff:ffff
142ff24:8d0::/28ff24:8df:ffff:ffff:ffff:ffff:ffff:ffff
143ff24:8e0::/28ff24:8ef:ffff:ffff:ffff:ffff:ffff:ffff
144ff24:8f0::/28ff24:8ff:ffff:ffff:ffff:ffff:ffff:ffff
145ff24:900::/28ff24:90f:ffff:ffff:ffff:ffff:ffff:ffff
146ff24:910::/28ff24:91f:ffff:ffff:ffff:ffff:ffff:ffff
147ff24:920::/28ff24:92f:ffff:ffff:ffff:ffff:ffff:ffff
148ff24:930::/28ff24:93f:ffff:ffff:ffff:ffff:ffff:ffff
149ff24:940::/28ff24:94f:ffff:ffff:ffff:ffff:ffff:ffff
150ff24:950::/28ff24:95f:ffff:ffff:ffff:ffff:ffff:ffff
151ff24:960::/28ff24:96f:ffff:ffff:ffff:ffff:ffff:ffff
152ff24:970::/28ff24:97f:ffff:ffff:ffff:ffff:ffff:ffff
153ff24:980::/28ff24:98f:ffff:ffff:ffff:ffff:ffff:ffff
154ff24:990::/28ff24:99f:ffff:ffff:ffff:ffff:ffff:ffff
155ff24:9a0::/28ff24:9af:ffff:ffff:ffff:ffff:ffff:ffff
156ff24:9b0::/28ff24:9bf:ffff:ffff:ffff:ffff:ffff:ffff
157ff24:9c0::/28ff24:9cf:ffff:ffff:ffff:ffff:ffff:ffff
158ff24:9d0::/28ff24:9df:ffff:ffff:ffff:ffff:ffff:ffff
159ff24:9e0::/28ff24:9ef:ffff:ffff:ffff:ffff:ffff:ffff
160ff24:9f0::/28ff24:9ff:ffff:ffff:ffff:ffff:ffff:ffff
161ff24:a00::/28ff24:a0f:ffff:ffff:ffff:ffff:ffff:ffff
162ff24:a10::/28ff24:a1f:ffff:ffff:ffff:ffff:ffff:ffff
163ff24:a20::/28ff24:a2f:ffff:ffff:ffff:ffff:ffff:ffff
164ff24:a30::/28ff24:a3f:ffff:ffff:ffff:ffff:ffff:ffff
165ff24:a40::/28ff24:a4f:ffff:ffff:ffff:ffff:ffff:ffff
166ff24:a50::/28ff24:a5f:ffff:ffff:ffff:ffff:ffff:ffff
167ff24:a60::/28ff24:a6f:ffff:ffff:ffff:ffff:ffff:ffff
168ff24:a70::/28ff24:a7f:ffff:ffff:ffff:ffff:ffff:ffff
169ff24:a80::/28ff24:a8f:ffff:ffff:ffff:ffff:ffff:ffff
170ff24:a90::/28ff24:a9f:ffff:ffff:ffff:ffff:ffff:ffff
171ff24:aa0::/28ff24:aaf:ffff:ffff:ffff:ffff:ffff:ffff
172ff24:ab0::/28ff24:abf:ffff:ffff:ffff:ffff:ffff:ffff
173ff24:ac0::/28ff24:acf:ffff:ffff:ffff:ffff:ffff:ffff
174ff24:ad0::/28ff24:adf:ffff:ffff:ffff:ffff:ffff:ffff
175ff24:ae0::/28ff24:aef:ffff:ffff:ffff:ffff:ffff:ffff
176ff24:af0::/28ff24:aff:ffff:ffff:ffff:ffff:ffff:ffff
177ff24:b00::/28ff24:b0f:ffff:ffff:ffff:ffff:ffff:ffff
178ff24:b10::/28ff24:b1f:ffff:ffff:ffff:ffff:ffff:ffff
179ff24:b20::/28ff24:b2f:ffff:ffff:ffff:ffff:ffff:ffff
180ff24:b30::/28ff24:b3f:ffff:ffff:ffff:ffff:ffff:ffff
181ff24:b40::/28ff24:b4f:ffff:ffff:ffff:ffff:ffff:ffff
182ff24:b50::/28ff24:b5f:ffff:ffff:ffff:ffff:ffff:ffff
183ff24:b60::/28ff24:b6f:ffff:ffff:ffff:ffff:ffff:ffff
184ff24:b70::/28ff24:b7f:ffff:ffff:ffff:ffff:ffff:ffff
185ff24:b80::/28ff24:b8f:ffff:ffff:ffff:ffff:ffff:ffff
186ff24:b90::/28ff24:b9f:ffff:ffff:ffff:ffff:ffff:ffff
187ff24:ba0::/28ff24:baf:ffff:ffff:ffff:ffff:ffff:ffff
188ff24:bb0::/28ff24:bbf:ffff:ffff:ffff:ffff:ffff:ffff
189ff24:bc0::/28ff24:bcf:ffff:ffff:ffff:ffff:ffff:ffff
190ff24:bd0::/28ff24:bdf:ffff:ffff:ffff:ffff:ffff:ffff
191ff24:be0::/28ff24:bef:ffff:ffff:ffff:ffff:ffff:ffff
192ff24:bf0::/28ff24:bff:ffff:ffff:ffff:ffff:ffff:ffff
193ff24:c00::/28ff24:c0f:ffff:ffff:ffff:ffff:ffff:ffff
194ff24:c10::/28ff24:c1f:ffff:ffff:ffff:ffff:ffff:ffff
195ff24:c20::/28ff24:c2f:ffff:ffff:ffff:ffff:ffff:ffff
196ff24:c30::/28ff24:c3f:ffff:ffff:ffff:ffff:ffff:ffff
197ff24:c40::/28ff24:c4f:ffff:ffff:ffff:ffff:ffff:ffff
198ff24:c50::/28ff24:c5f:ffff:ffff:ffff:ffff:ffff:ffff
199ff24:c60::/28ff24:c6f:ffff:ffff:ffff:ffff:ffff:ffff
200ff24:c70::/28ff24:c7f:ffff:ffff:ffff:ffff:ffff:ffff
201ff24:c80::/28ff24:c8f:ffff:ffff:ffff:ffff:ffff:ffff
202ff24:c90::/28ff24:c9f:ffff:ffff:ffff:ffff:ffff:ffff
203ff24:ca0::/28ff24:caf:ffff:ffff:ffff:ffff:ffff:ffff
204ff24:cb0::/28ff24:cbf:ffff:ffff:ffff:ffff:ffff:ffff
205ff24:cc0::/28ff24:ccf:ffff:ffff:ffff:ffff:ffff:ffff
206ff24:cd0::/28ff24:cdf:ffff:ffff:ffff:ffff:ffff:ffff
207ff24:ce0::/28ff24:cef:ffff:ffff:ffff:ffff:ffff:ffff
208ff24:cf0::/28ff24:cff:ffff:ffff:ffff:ffff:ffff:ffff
209ff24:d00::/28ff24:d0f:ffff:ffff:ffff:ffff:ffff:ffff
210ff24:d10::/28ff24:d1f:ffff:ffff:ffff:ffff:ffff:ffff
211ff24:d20::/28ff24:d2f:ffff:ffff:ffff:ffff:ffff:ffff
212ff24:d30::/28ff24:d3f:ffff:ffff:ffff:ffff:ffff:ffff
213ff24:d40::/28ff24:d4f:ffff:ffff:ffff:ffff:ffff:ffff
214ff24:d50::/28ff24:d5f:ffff:ffff:ffff:ffff:ffff:ffff
215ff24:d60::/28ff24:d6f:ffff:ffff:ffff:ffff:ffff:ffff
216ff24:d70::/28ff24:d7f:ffff:ffff:ffff:ffff:ffff:ffff
217ff24:d80::/28ff24:d8f:ffff:ffff:ffff:ffff:ffff:ffff
218ff24:d90::/28ff24:d9f:ffff:ffff:ffff:ffff:ffff:ffff
219ff24:da0::/28ff24:daf:ffff:ffff:ffff:ffff:ffff:ffff
220ff24:db0::/28ff24:dbf:ffff:ffff:ffff:ffff:ffff:ffff
221ff24:dc0::/28ff24:dcf:ffff:ffff:ffff:ffff:ffff:ffff
222ff24:dd0::/28ff24:ddf:ffff:ffff:ffff:ffff:ffff:ffff
223ff24:de0::/28ff24:def:ffff:ffff:ffff:ffff:ffff:ffff
224ff24:df0::/28ff24:dff:ffff:ffff:ffff:ffff:ffff:ffff
225ff24:e00::/28ff24:e0f:ffff:ffff:ffff:ffff:ffff:ffff
226ff24:e10::/28ff24:e1f:ffff:ffff:ffff:ffff:ffff:ffff
227ff24:e20::/28ff24:e2f:ffff:ffff:ffff:ffff:ffff:ffff
228ff24:e30::/28ff24:e3f:ffff:ffff:ffff:ffff:ffff:ffff
229ff24:e40::/28ff24:e4f:ffff:ffff:ffff:ffff:ffff:ffff
230ff24:e50::/28ff24:e5f:ffff:ffff:ffff:ffff:ffff:ffff
231ff24:e60::/28ff24:e6f:ffff:ffff:ffff:ffff:ffff:ffff
232ff24:e70::/28ff24:e7f:ffff:ffff:ffff:ffff:ffff:ffff
233ff24:e80::/28ff24:e8f:ffff:ffff:ffff:ffff:ffff:ffff
234ff24:e90::/28ff24:e9f:ffff:ffff:ffff:ffff:ffff:ffff
235ff24:ea0::/28ff24:eaf:ffff:ffff:ffff:ffff:ffff:ffff
236ff24:eb0::/28ff24:ebf:ffff:ffff:ffff:ffff:ffff:ffff
237ff24:ec0::/28ff24:ecf:ffff:ffff:ffff:ffff:ffff:ffff
238ff24:ed0::/28ff24:edf:ffff:ffff:ffff:ffff:ffff:ffff
239ff24:ee0::/28ff24:eef:ffff:ffff:ffff:ffff:ffff:ffff
240ff24:ef0::/28ff24:eff:ffff:ffff:ffff:ffff:ffff:ffff
241ff24:f00::/28ff24:f0f:ffff:ffff:ffff:ffff:ffff:ffff
242ff24:f10::/28ff24:f1f:ffff:ffff:ffff:ffff:ffff:ffff
243ff24:f20::/28ff24:f2f:ffff:ffff:ffff:ffff:ffff:ffff
244ff24:f30::/28ff24:f3f:ffff:ffff:ffff:ffff:ffff:ffff
245ff24:f40::/28ff24:f4f:ffff:ffff:ffff:ffff:ffff:ffff
246ff24:f50::/28ff24:f5f:ffff:ffff:ffff:ffff:ffff:ffff
247ff24:f60::/28ff24:f6f:ffff:ffff:ffff:ffff:ffff:ffff
248ff24:f70::/28ff24:f7f:ffff:ffff:ffff:ffff:ffff:ffff
249ff24:f80::/28ff24:f8f:ffff:ffff:ffff:ffff:ffff:ffff
250ff24:f90::/28ff24:f9f:ffff:ffff:ffff:ffff:ffff:ffff
251ff24:fa0::/28ff24:faf:ffff:ffff:ffff:ffff:ffff:ffff
252ff24:fb0::/28ff24:fbf:ffff:ffff:ffff:ffff:ffff:ffff
253ff24:fc0::/28ff24:fcf:ffff:ffff:ffff:ffff:ffff:ffff
254ff24:fd0::/28ff24:fdf:ffff:ffff:ffff:ffff:ffff:ffff
255ff24:fe0::/28ff24:fef:ffff:ffff:ffff:ffff:ffff:ffff
256ff24:ff0::/28ff24: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.