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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
ff86::/16
First address
ff86::
Last address
ff86: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
ff86:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
6.8.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)

ff86::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
1ff86::/28ff86:f:ffff:ffff:ffff:ffff:ffff:ffff
2ff86:10::/28ff86:1f:ffff:ffff:ffff:ffff:ffff:ffff
3ff86:20::/28ff86:2f:ffff:ffff:ffff:ffff:ffff:ffff
4ff86:30::/28ff86:3f:ffff:ffff:ffff:ffff:ffff:ffff
5ff86:40::/28ff86:4f:ffff:ffff:ffff:ffff:ffff:ffff
6ff86:50::/28ff86:5f:ffff:ffff:ffff:ffff:ffff:ffff
7ff86:60::/28ff86:6f:ffff:ffff:ffff:ffff:ffff:ffff
8ff86:70::/28ff86:7f:ffff:ffff:ffff:ffff:ffff:ffff
9ff86:80::/28ff86:8f:ffff:ffff:ffff:ffff:ffff:ffff
10ff86:90::/28ff86:9f:ffff:ffff:ffff:ffff:ffff:ffff
11ff86:a0::/28ff86:af:ffff:ffff:ffff:ffff:ffff:ffff
12ff86:b0::/28ff86:bf:ffff:ffff:ffff:ffff:ffff:ffff
13ff86:c0::/28ff86:cf:ffff:ffff:ffff:ffff:ffff:ffff
14ff86:d0::/28ff86:df:ffff:ffff:ffff:ffff:ffff:ffff
15ff86:e0::/28ff86:ef:ffff:ffff:ffff:ffff:ffff:ffff
16ff86:f0::/28ff86:ff:ffff:ffff:ffff:ffff:ffff:ffff
17ff86:100::/28ff86:10f:ffff:ffff:ffff:ffff:ffff:ffff
18ff86:110::/28ff86:11f:ffff:ffff:ffff:ffff:ffff:ffff
19ff86:120::/28ff86:12f:ffff:ffff:ffff:ffff:ffff:ffff
20ff86:130::/28ff86:13f:ffff:ffff:ffff:ffff:ffff:ffff
21ff86:140::/28ff86:14f:ffff:ffff:ffff:ffff:ffff:ffff
22ff86:150::/28ff86:15f:ffff:ffff:ffff:ffff:ffff:ffff
23ff86:160::/28ff86:16f:ffff:ffff:ffff:ffff:ffff:ffff
24ff86:170::/28ff86:17f:ffff:ffff:ffff:ffff:ffff:ffff
25ff86:180::/28ff86:18f:ffff:ffff:ffff:ffff:ffff:ffff
26ff86:190::/28ff86:19f:ffff:ffff:ffff:ffff:ffff:ffff
27ff86:1a0::/28ff86:1af:ffff:ffff:ffff:ffff:ffff:ffff
28ff86:1b0::/28ff86:1bf:ffff:ffff:ffff:ffff:ffff:ffff
29ff86:1c0::/28ff86:1cf:ffff:ffff:ffff:ffff:ffff:ffff
30ff86:1d0::/28ff86:1df:ffff:ffff:ffff:ffff:ffff:ffff
31ff86:1e0::/28ff86:1ef:ffff:ffff:ffff:ffff:ffff:ffff
32ff86:1f0::/28ff86:1ff:ffff:ffff:ffff:ffff:ffff:ffff
33ff86:200::/28ff86:20f:ffff:ffff:ffff:ffff:ffff:ffff
34ff86:210::/28ff86:21f:ffff:ffff:ffff:ffff:ffff:ffff
35ff86:220::/28ff86:22f:ffff:ffff:ffff:ffff:ffff:ffff
36ff86:230::/28ff86:23f:ffff:ffff:ffff:ffff:ffff:ffff
37ff86:240::/28ff86:24f:ffff:ffff:ffff:ffff:ffff:ffff
38ff86:250::/28ff86:25f:ffff:ffff:ffff:ffff:ffff:ffff
39ff86:260::/28ff86:26f:ffff:ffff:ffff:ffff:ffff:ffff
40ff86:270::/28ff86:27f:ffff:ffff:ffff:ffff:ffff:ffff
41ff86:280::/28ff86:28f:ffff:ffff:ffff:ffff:ffff:ffff
42ff86:290::/28ff86:29f:ffff:ffff:ffff:ffff:ffff:ffff
43ff86:2a0::/28ff86:2af:ffff:ffff:ffff:ffff:ffff:ffff
44ff86:2b0::/28ff86:2bf:ffff:ffff:ffff:ffff:ffff:ffff
45ff86:2c0::/28ff86:2cf:ffff:ffff:ffff:ffff:ffff:ffff
46ff86:2d0::/28ff86:2df:ffff:ffff:ffff:ffff:ffff:ffff
47ff86:2e0::/28ff86:2ef:ffff:ffff:ffff:ffff:ffff:ffff
48ff86:2f0::/28ff86:2ff:ffff:ffff:ffff:ffff:ffff:ffff
49ff86:300::/28ff86:30f:ffff:ffff:ffff:ffff:ffff:ffff
50ff86:310::/28ff86:31f:ffff:ffff:ffff:ffff:ffff:ffff
51ff86:320::/28ff86:32f:ffff:ffff:ffff:ffff:ffff:ffff
52ff86:330::/28ff86:33f:ffff:ffff:ffff:ffff:ffff:ffff
53ff86:340::/28ff86:34f:ffff:ffff:ffff:ffff:ffff:ffff
54ff86:350::/28ff86:35f:ffff:ffff:ffff:ffff:ffff:ffff
55ff86:360::/28ff86:36f:ffff:ffff:ffff:ffff:ffff:ffff
56ff86:370::/28ff86:37f:ffff:ffff:ffff:ffff:ffff:ffff
57ff86:380::/28ff86:38f:ffff:ffff:ffff:ffff:ffff:ffff
58ff86:390::/28ff86:39f:ffff:ffff:ffff:ffff:ffff:ffff
59ff86:3a0::/28ff86:3af:ffff:ffff:ffff:ffff:ffff:ffff
60ff86:3b0::/28ff86:3bf:ffff:ffff:ffff:ffff:ffff:ffff
61ff86:3c0::/28ff86:3cf:ffff:ffff:ffff:ffff:ffff:ffff
62ff86:3d0::/28ff86:3df:ffff:ffff:ffff:ffff:ffff:ffff
63ff86:3e0::/28ff86:3ef:ffff:ffff:ffff:ffff:ffff:ffff
64ff86:3f0::/28ff86:3ff:ffff:ffff:ffff:ffff:ffff:ffff
65ff86:400::/28ff86:40f:ffff:ffff:ffff:ffff:ffff:ffff
66ff86:410::/28ff86:41f:ffff:ffff:ffff:ffff:ffff:ffff
67ff86:420::/28ff86:42f:ffff:ffff:ffff:ffff:ffff:ffff
68ff86:430::/28ff86:43f:ffff:ffff:ffff:ffff:ffff:ffff
69ff86:440::/28ff86:44f:ffff:ffff:ffff:ffff:ffff:ffff
70ff86:450::/28ff86:45f:ffff:ffff:ffff:ffff:ffff:ffff
71ff86:460::/28ff86:46f:ffff:ffff:ffff:ffff:ffff:ffff
72ff86:470::/28ff86:47f:ffff:ffff:ffff:ffff:ffff:ffff
73ff86:480::/28ff86:48f:ffff:ffff:ffff:ffff:ffff:ffff
74ff86:490::/28ff86:49f:ffff:ffff:ffff:ffff:ffff:ffff
75ff86:4a0::/28ff86:4af:ffff:ffff:ffff:ffff:ffff:ffff
76ff86:4b0::/28ff86:4bf:ffff:ffff:ffff:ffff:ffff:ffff
77ff86:4c0::/28ff86:4cf:ffff:ffff:ffff:ffff:ffff:ffff
78ff86:4d0::/28ff86:4df:ffff:ffff:ffff:ffff:ffff:ffff
79ff86:4e0::/28ff86:4ef:ffff:ffff:ffff:ffff:ffff:ffff
80ff86:4f0::/28ff86:4ff:ffff:ffff:ffff:ffff:ffff:ffff
81ff86:500::/28ff86:50f:ffff:ffff:ffff:ffff:ffff:ffff
82ff86:510::/28ff86:51f:ffff:ffff:ffff:ffff:ffff:ffff
83ff86:520::/28ff86:52f:ffff:ffff:ffff:ffff:ffff:ffff
84ff86:530::/28ff86:53f:ffff:ffff:ffff:ffff:ffff:ffff
85ff86:540::/28ff86:54f:ffff:ffff:ffff:ffff:ffff:ffff
86ff86:550::/28ff86:55f:ffff:ffff:ffff:ffff:ffff:ffff
87ff86:560::/28ff86:56f:ffff:ffff:ffff:ffff:ffff:ffff
88ff86:570::/28ff86:57f:ffff:ffff:ffff:ffff:ffff:ffff
89ff86:580::/28ff86:58f:ffff:ffff:ffff:ffff:ffff:ffff
90ff86:590::/28ff86:59f:ffff:ffff:ffff:ffff:ffff:ffff
91ff86:5a0::/28ff86:5af:ffff:ffff:ffff:ffff:ffff:ffff
92ff86:5b0::/28ff86:5bf:ffff:ffff:ffff:ffff:ffff:ffff
93ff86:5c0::/28ff86:5cf:ffff:ffff:ffff:ffff:ffff:ffff
94ff86:5d0::/28ff86:5df:ffff:ffff:ffff:ffff:ffff:ffff
95ff86:5e0::/28ff86:5ef:ffff:ffff:ffff:ffff:ffff:ffff
96ff86:5f0::/28ff86:5ff:ffff:ffff:ffff:ffff:ffff:ffff
97ff86:600::/28ff86:60f:ffff:ffff:ffff:ffff:ffff:ffff
98ff86:610::/28ff86:61f:ffff:ffff:ffff:ffff:ffff:ffff
99ff86:620::/28ff86:62f:ffff:ffff:ffff:ffff:ffff:ffff
100ff86:630::/28ff86:63f:ffff:ffff:ffff:ffff:ffff:ffff
101ff86:640::/28ff86:64f:ffff:ffff:ffff:ffff:ffff:ffff
102ff86:650::/28ff86:65f:ffff:ffff:ffff:ffff:ffff:ffff
103ff86:660::/28ff86:66f:ffff:ffff:ffff:ffff:ffff:ffff
104ff86:670::/28ff86:67f:ffff:ffff:ffff:ffff:ffff:ffff
105ff86:680::/28ff86:68f:ffff:ffff:ffff:ffff:ffff:ffff
106ff86:690::/28ff86:69f:ffff:ffff:ffff:ffff:ffff:ffff
107ff86:6a0::/28ff86:6af:ffff:ffff:ffff:ffff:ffff:ffff
108ff86:6b0::/28ff86:6bf:ffff:ffff:ffff:ffff:ffff:ffff
109ff86:6c0::/28ff86:6cf:ffff:ffff:ffff:ffff:ffff:ffff
110ff86:6d0::/28ff86:6df:ffff:ffff:ffff:ffff:ffff:ffff
111ff86:6e0::/28ff86:6ef:ffff:ffff:ffff:ffff:ffff:ffff
112ff86:6f0::/28ff86:6ff:ffff:ffff:ffff:ffff:ffff:ffff
113ff86:700::/28ff86:70f:ffff:ffff:ffff:ffff:ffff:ffff
114ff86:710::/28ff86:71f:ffff:ffff:ffff:ffff:ffff:ffff
115ff86:720::/28ff86:72f:ffff:ffff:ffff:ffff:ffff:ffff
116ff86:730::/28ff86:73f:ffff:ffff:ffff:ffff:ffff:ffff
117ff86:740::/28ff86:74f:ffff:ffff:ffff:ffff:ffff:ffff
118ff86:750::/28ff86:75f:ffff:ffff:ffff:ffff:ffff:ffff
119ff86:760::/28ff86:76f:ffff:ffff:ffff:ffff:ffff:ffff
120ff86:770::/28ff86:77f:ffff:ffff:ffff:ffff:ffff:ffff
121ff86:780::/28ff86:78f:ffff:ffff:ffff:ffff:ffff:ffff
122ff86:790::/28ff86:79f:ffff:ffff:ffff:ffff:ffff:ffff
123ff86:7a0::/28ff86:7af:ffff:ffff:ffff:ffff:ffff:ffff
124ff86:7b0::/28ff86:7bf:ffff:ffff:ffff:ffff:ffff:ffff
125ff86:7c0::/28ff86:7cf:ffff:ffff:ffff:ffff:ffff:ffff
126ff86:7d0::/28ff86:7df:ffff:ffff:ffff:ffff:ffff:ffff
127ff86:7e0::/28ff86:7ef:ffff:ffff:ffff:ffff:ffff:ffff
128ff86:7f0::/28ff86:7ff:ffff:ffff:ffff:ffff:ffff:ffff
129ff86:800::/28ff86:80f:ffff:ffff:ffff:ffff:ffff:ffff
130ff86:810::/28ff86:81f:ffff:ffff:ffff:ffff:ffff:ffff
131ff86:820::/28ff86:82f:ffff:ffff:ffff:ffff:ffff:ffff
132ff86:830::/28ff86:83f:ffff:ffff:ffff:ffff:ffff:ffff
133ff86:840::/28ff86:84f:ffff:ffff:ffff:ffff:ffff:ffff
134ff86:850::/28ff86:85f:ffff:ffff:ffff:ffff:ffff:ffff
135ff86:860::/28ff86:86f:ffff:ffff:ffff:ffff:ffff:ffff
136ff86:870::/28ff86:87f:ffff:ffff:ffff:ffff:ffff:ffff
137ff86:880::/28ff86:88f:ffff:ffff:ffff:ffff:ffff:ffff
138ff86:890::/28ff86:89f:ffff:ffff:ffff:ffff:ffff:ffff
139ff86:8a0::/28ff86:8af:ffff:ffff:ffff:ffff:ffff:ffff
140ff86:8b0::/28ff86:8bf:ffff:ffff:ffff:ffff:ffff:ffff
141ff86:8c0::/28ff86:8cf:ffff:ffff:ffff:ffff:ffff:ffff
142ff86:8d0::/28ff86:8df:ffff:ffff:ffff:ffff:ffff:ffff
143ff86:8e0::/28ff86:8ef:ffff:ffff:ffff:ffff:ffff:ffff
144ff86:8f0::/28ff86:8ff:ffff:ffff:ffff:ffff:ffff:ffff
145ff86:900::/28ff86:90f:ffff:ffff:ffff:ffff:ffff:ffff
146ff86:910::/28ff86:91f:ffff:ffff:ffff:ffff:ffff:ffff
147ff86:920::/28ff86:92f:ffff:ffff:ffff:ffff:ffff:ffff
148ff86:930::/28ff86:93f:ffff:ffff:ffff:ffff:ffff:ffff
149ff86:940::/28ff86:94f:ffff:ffff:ffff:ffff:ffff:ffff
150ff86:950::/28ff86:95f:ffff:ffff:ffff:ffff:ffff:ffff
151ff86:960::/28ff86:96f:ffff:ffff:ffff:ffff:ffff:ffff
152ff86:970::/28ff86:97f:ffff:ffff:ffff:ffff:ffff:ffff
153ff86:980::/28ff86:98f:ffff:ffff:ffff:ffff:ffff:ffff
154ff86:990::/28ff86:99f:ffff:ffff:ffff:ffff:ffff:ffff
155ff86:9a0::/28ff86:9af:ffff:ffff:ffff:ffff:ffff:ffff
156ff86:9b0::/28ff86:9bf:ffff:ffff:ffff:ffff:ffff:ffff
157ff86:9c0::/28ff86:9cf:ffff:ffff:ffff:ffff:ffff:ffff
158ff86:9d0::/28ff86:9df:ffff:ffff:ffff:ffff:ffff:ffff
159ff86:9e0::/28ff86:9ef:ffff:ffff:ffff:ffff:ffff:ffff
160ff86:9f0::/28ff86:9ff:ffff:ffff:ffff:ffff:ffff:ffff
161ff86:a00::/28ff86:a0f:ffff:ffff:ffff:ffff:ffff:ffff
162ff86:a10::/28ff86:a1f:ffff:ffff:ffff:ffff:ffff:ffff
163ff86:a20::/28ff86:a2f:ffff:ffff:ffff:ffff:ffff:ffff
164ff86:a30::/28ff86:a3f:ffff:ffff:ffff:ffff:ffff:ffff
165ff86:a40::/28ff86:a4f:ffff:ffff:ffff:ffff:ffff:ffff
166ff86:a50::/28ff86:a5f:ffff:ffff:ffff:ffff:ffff:ffff
167ff86:a60::/28ff86:a6f:ffff:ffff:ffff:ffff:ffff:ffff
168ff86:a70::/28ff86:a7f:ffff:ffff:ffff:ffff:ffff:ffff
169ff86:a80::/28ff86:a8f:ffff:ffff:ffff:ffff:ffff:ffff
170ff86:a90::/28ff86:a9f:ffff:ffff:ffff:ffff:ffff:ffff
171ff86:aa0::/28ff86:aaf:ffff:ffff:ffff:ffff:ffff:ffff
172ff86:ab0::/28ff86:abf:ffff:ffff:ffff:ffff:ffff:ffff
173ff86:ac0::/28ff86:acf:ffff:ffff:ffff:ffff:ffff:ffff
174ff86:ad0::/28ff86:adf:ffff:ffff:ffff:ffff:ffff:ffff
175ff86:ae0::/28ff86:aef:ffff:ffff:ffff:ffff:ffff:ffff
176ff86:af0::/28ff86:aff:ffff:ffff:ffff:ffff:ffff:ffff
177ff86:b00::/28ff86:b0f:ffff:ffff:ffff:ffff:ffff:ffff
178ff86:b10::/28ff86:b1f:ffff:ffff:ffff:ffff:ffff:ffff
179ff86:b20::/28ff86:b2f:ffff:ffff:ffff:ffff:ffff:ffff
180ff86:b30::/28ff86:b3f:ffff:ffff:ffff:ffff:ffff:ffff
181ff86:b40::/28ff86:b4f:ffff:ffff:ffff:ffff:ffff:ffff
182ff86:b50::/28ff86:b5f:ffff:ffff:ffff:ffff:ffff:ffff
183ff86:b60::/28ff86:b6f:ffff:ffff:ffff:ffff:ffff:ffff
184ff86:b70::/28ff86:b7f:ffff:ffff:ffff:ffff:ffff:ffff
185ff86:b80::/28ff86:b8f:ffff:ffff:ffff:ffff:ffff:ffff
186ff86:b90::/28ff86:b9f:ffff:ffff:ffff:ffff:ffff:ffff
187ff86:ba0::/28ff86:baf:ffff:ffff:ffff:ffff:ffff:ffff
188ff86:bb0::/28ff86:bbf:ffff:ffff:ffff:ffff:ffff:ffff
189ff86:bc0::/28ff86:bcf:ffff:ffff:ffff:ffff:ffff:ffff
190ff86:bd0::/28ff86:bdf:ffff:ffff:ffff:ffff:ffff:ffff
191ff86:be0::/28ff86:bef:ffff:ffff:ffff:ffff:ffff:ffff
192ff86:bf0::/28ff86:bff:ffff:ffff:ffff:ffff:ffff:ffff
193ff86:c00::/28ff86:c0f:ffff:ffff:ffff:ffff:ffff:ffff
194ff86:c10::/28ff86:c1f:ffff:ffff:ffff:ffff:ffff:ffff
195ff86:c20::/28ff86:c2f:ffff:ffff:ffff:ffff:ffff:ffff
196ff86:c30::/28ff86:c3f:ffff:ffff:ffff:ffff:ffff:ffff
197ff86:c40::/28ff86:c4f:ffff:ffff:ffff:ffff:ffff:ffff
198ff86:c50::/28ff86:c5f:ffff:ffff:ffff:ffff:ffff:ffff
199ff86:c60::/28ff86:c6f:ffff:ffff:ffff:ffff:ffff:ffff
200ff86:c70::/28ff86:c7f:ffff:ffff:ffff:ffff:ffff:ffff
201ff86:c80::/28ff86:c8f:ffff:ffff:ffff:ffff:ffff:ffff
202ff86:c90::/28ff86:c9f:ffff:ffff:ffff:ffff:ffff:ffff
203ff86:ca0::/28ff86:caf:ffff:ffff:ffff:ffff:ffff:ffff
204ff86:cb0::/28ff86:cbf:ffff:ffff:ffff:ffff:ffff:ffff
205ff86:cc0::/28ff86:ccf:ffff:ffff:ffff:ffff:ffff:ffff
206ff86:cd0::/28ff86:cdf:ffff:ffff:ffff:ffff:ffff:ffff
207ff86:ce0::/28ff86:cef:ffff:ffff:ffff:ffff:ffff:ffff
208ff86:cf0::/28ff86:cff:ffff:ffff:ffff:ffff:ffff:ffff
209ff86:d00::/28ff86:d0f:ffff:ffff:ffff:ffff:ffff:ffff
210ff86:d10::/28ff86:d1f:ffff:ffff:ffff:ffff:ffff:ffff
211ff86:d20::/28ff86:d2f:ffff:ffff:ffff:ffff:ffff:ffff
212ff86:d30::/28ff86:d3f:ffff:ffff:ffff:ffff:ffff:ffff
213ff86:d40::/28ff86:d4f:ffff:ffff:ffff:ffff:ffff:ffff
214ff86:d50::/28ff86:d5f:ffff:ffff:ffff:ffff:ffff:ffff
215ff86:d60::/28ff86:d6f:ffff:ffff:ffff:ffff:ffff:ffff
216ff86:d70::/28ff86:d7f:ffff:ffff:ffff:ffff:ffff:ffff
217ff86:d80::/28ff86:d8f:ffff:ffff:ffff:ffff:ffff:ffff
218ff86:d90::/28ff86:d9f:ffff:ffff:ffff:ffff:ffff:ffff
219ff86:da0::/28ff86:daf:ffff:ffff:ffff:ffff:ffff:ffff
220ff86:db0::/28ff86:dbf:ffff:ffff:ffff:ffff:ffff:ffff
221ff86:dc0::/28ff86:dcf:ffff:ffff:ffff:ffff:ffff:ffff
222ff86:dd0::/28ff86:ddf:ffff:ffff:ffff:ffff:ffff:ffff
223ff86:de0::/28ff86:def:ffff:ffff:ffff:ffff:ffff:ffff
224ff86:df0::/28ff86:dff:ffff:ffff:ffff:ffff:ffff:ffff
225ff86:e00::/28ff86:e0f:ffff:ffff:ffff:ffff:ffff:ffff
226ff86:e10::/28ff86:e1f:ffff:ffff:ffff:ffff:ffff:ffff
227ff86:e20::/28ff86:e2f:ffff:ffff:ffff:ffff:ffff:ffff
228ff86:e30::/28ff86:e3f:ffff:ffff:ffff:ffff:ffff:ffff
229ff86:e40::/28ff86:e4f:ffff:ffff:ffff:ffff:ffff:ffff
230ff86:e50::/28ff86:e5f:ffff:ffff:ffff:ffff:ffff:ffff
231ff86:e60::/28ff86:e6f:ffff:ffff:ffff:ffff:ffff:ffff
232ff86:e70::/28ff86:e7f:ffff:ffff:ffff:ffff:ffff:ffff
233ff86:e80::/28ff86:e8f:ffff:ffff:ffff:ffff:ffff:ffff
234ff86:e90::/28ff86:e9f:ffff:ffff:ffff:ffff:ffff:ffff
235ff86:ea0::/28ff86:eaf:ffff:ffff:ffff:ffff:ffff:ffff
236ff86:eb0::/28ff86:ebf:ffff:ffff:ffff:ffff:ffff:ffff
237ff86:ec0::/28ff86:ecf:ffff:ffff:ffff:ffff:ffff:ffff
238ff86:ed0::/28ff86:edf:ffff:ffff:ffff:ffff:ffff:ffff
239ff86:ee0::/28ff86:eef:ffff:ffff:ffff:ffff:ffff:ffff
240ff86:ef0::/28ff86:eff:ffff:ffff:ffff:ffff:ffff:ffff
241ff86:f00::/28ff86:f0f:ffff:ffff:ffff:ffff:ffff:ffff
242ff86:f10::/28ff86:f1f:ffff:ffff:ffff:ffff:ffff:ffff
243ff86:f20::/28ff86:f2f:ffff:ffff:ffff:ffff:ffff:ffff
244ff86:f30::/28ff86:f3f:ffff:ffff:ffff:ffff:ffff:ffff
245ff86:f40::/28ff86:f4f:ffff:ffff:ffff:ffff:ffff:ffff
246ff86:f50::/28ff86:f5f:ffff:ffff:ffff:ffff:ffff:ffff
247ff86:f60::/28ff86:f6f:ffff:ffff:ffff:ffff:ffff:ffff
248ff86:f70::/28ff86:f7f:ffff:ffff:ffff:ffff:ffff:ffff
249ff86:f80::/28ff86:f8f:ffff:ffff:ffff:ffff:ffff:ffff
250ff86:f90::/28ff86:f9f:ffff:ffff:ffff:ffff:ffff:ffff
251ff86:fa0::/28ff86:faf:ffff:ffff:ffff:ffff:ffff:ffff
252ff86:fb0::/28ff86:fbf:ffff:ffff:ffff:ffff:ffff:ffff
253ff86:fc0::/28ff86:fcf:ffff:ffff:ffff:ffff:ffff:ffff
254ff86:fd0::/28ff86:fdf:ffff:ffff:ffff:ffff:ffff:ffff
255ff86:fe0::/28ff86:fef:ffff:ffff:ffff:ffff:ffff:ffff
256ff86:ff0::/28ff86: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.