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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/17
Addresses2^111
/64 networks2^47
Network
ff89::/17
First address
ff89::
Last address
ff89:7fff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
2,596,148,429,267,413,814,265,248,164,610,048 (2^111)
/64 networks (LANs)
140,737,488,355,328 (2^47)
Full form
ff89:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zones
0.9.8.f.f.ip6.arpa
1.9.8.f.f.ip6.arpa
2.9.8.f.f.ip6.arpa
3.9.8.f.f.ip6.arpa
4.9.8.f.f.ip6.arpa
5.9.8.f.f.ip6.arpa
6.9.8.f.f.ip6.arpa
7.9.8.f.f.ip6.arpa
/17 is not on a 4-bit boundary, so it takes 8 /20 zones.
Split into smaller subnets/28
/18 (2)/19 (4)/20 (8)/21 (16)/24 (128)/28 (2,048)/32 (32,768)

ff89::/17 makes 2,048 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
1ff89::/28ff89:f:ffff:ffff:ffff:ffff:ffff:ffff
2ff89:10::/28ff89:1f:ffff:ffff:ffff:ffff:ffff:ffff
3ff89:20::/28ff89:2f:ffff:ffff:ffff:ffff:ffff:ffff
4ff89:30::/28ff89:3f:ffff:ffff:ffff:ffff:ffff:ffff
5ff89:40::/28ff89:4f:ffff:ffff:ffff:ffff:ffff:ffff
6ff89:50::/28ff89:5f:ffff:ffff:ffff:ffff:ffff:ffff
7ff89:60::/28ff89:6f:ffff:ffff:ffff:ffff:ffff:ffff
8ff89:70::/28ff89:7f:ffff:ffff:ffff:ffff:ffff:ffff
9ff89:80::/28ff89:8f:ffff:ffff:ffff:ffff:ffff:ffff
10ff89:90::/28ff89:9f:ffff:ffff:ffff:ffff:ffff:ffff
11ff89:a0::/28ff89:af:ffff:ffff:ffff:ffff:ffff:ffff
12ff89:b0::/28ff89:bf:ffff:ffff:ffff:ffff:ffff:ffff
13ff89:c0::/28ff89:cf:ffff:ffff:ffff:ffff:ffff:ffff
14ff89:d0::/28ff89:df:ffff:ffff:ffff:ffff:ffff:ffff
15ff89:e0::/28ff89:ef:ffff:ffff:ffff:ffff:ffff:ffff
16ff89:f0::/28ff89:ff:ffff:ffff:ffff:ffff:ffff:ffff
17ff89:100::/28ff89:10f:ffff:ffff:ffff:ffff:ffff:ffff
18ff89:110::/28ff89:11f:ffff:ffff:ffff:ffff:ffff:ffff
19ff89:120::/28ff89:12f:ffff:ffff:ffff:ffff:ffff:ffff
20ff89:130::/28ff89:13f:ffff:ffff:ffff:ffff:ffff:ffff
21ff89:140::/28ff89:14f:ffff:ffff:ffff:ffff:ffff:ffff
22ff89:150::/28ff89:15f:ffff:ffff:ffff:ffff:ffff:ffff
23ff89:160::/28ff89:16f:ffff:ffff:ffff:ffff:ffff:ffff
24ff89:170::/28ff89:17f:ffff:ffff:ffff:ffff:ffff:ffff
25ff89:180::/28ff89:18f:ffff:ffff:ffff:ffff:ffff:ffff
26ff89:190::/28ff89:19f:ffff:ffff:ffff:ffff:ffff:ffff
27ff89:1a0::/28ff89:1af:ffff:ffff:ffff:ffff:ffff:ffff
28ff89:1b0::/28ff89:1bf:ffff:ffff:ffff:ffff:ffff:ffff
29ff89:1c0::/28ff89:1cf:ffff:ffff:ffff:ffff:ffff:ffff
30ff89:1d0::/28ff89:1df:ffff:ffff:ffff:ffff:ffff:ffff
31ff89:1e0::/28ff89:1ef:ffff:ffff:ffff:ffff:ffff:ffff
32ff89:1f0::/28ff89:1ff:ffff:ffff:ffff:ffff:ffff:ffff
33ff89:200::/28ff89:20f:ffff:ffff:ffff:ffff:ffff:ffff
34ff89:210::/28ff89:21f:ffff:ffff:ffff:ffff:ffff:ffff
35ff89:220::/28ff89:22f:ffff:ffff:ffff:ffff:ffff:ffff
36ff89:230::/28ff89:23f:ffff:ffff:ffff:ffff:ffff:ffff
37ff89:240::/28ff89:24f:ffff:ffff:ffff:ffff:ffff:ffff
38ff89:250::/28ff89:25f:ffff:ffff:ffff:ffff:ffff:ffff
39ff89:260::/28ff89:26f:ffff:ffff:ffff:ffff:ffff:ffff
40ff89:270::/28ff89:27f:ffff:ffff:ffff:ffff:ffff:ffff
41ff89:280::/28ff89:28f:ffff:ffff:ffff:ffff:ffff:ffff
42ff89:290::/28ff89:29f:ffff:ffff:ffff:ffff:ffff:ffff
43ff89:2a0::/28ff89:2af:ffff:ffff:ffff:ffff:ffff:ffff
44ff89:2b0::/28ff89:2bf:ffff:ffff:ffff:ffff:ffff:ffff
45ff89:2c0::/28ff89:2cf:ffff:ffff:ffff:ffff:ffff:ffff
46ff89:2d0::/28ff89:2df:ffff:ffff:ffff:ffff:ffff:ffff
47ff89:2e0::/28ff89:2ef:ffff:ffff:ffff:ffff:ffff:ffff
48ff89:2f0::/28ff89:2ff:ffff:ffff:ffff:ffff:ffff:ffff
49ff89:300::/28ff89:30f:ffff:ffff:ffff:ffff:ffff:ffff
50ff89:310::/28ff89:31f:ffff:ffff:ffff:ffff:ffff:ffff
51ff89:320::/28ff89:32f:ffff:ffff:ffff:ffff:ffff:ffff
52ff89:330::/28ff89:33f:ffff:ffff:ffff:ffff:ffff:ffff
53ff89:340::/28ff89:34f:ffff:ffff:ffff:ffff:ffff:ffff
54ff89:350::/28ff89:35f:ffff:ffff:ffff:ffff:ffff:ffff
55ff89:360::/28ff89:36f:ffff:ffff:ffff:ffff:ffff:ffff
56ff89:370::/28ff89:37f:ffff:ffff:ffff:ffff:ffff:ffff
57ff89:380::/28ff89:38f:ffff:ffff:ffff:ffff:ffff:ffff
58ff89:390::/28ff89:39f:ffff:ffff:ffff:ffff:ffff:ffff
59ff89:3a0::/28ff89:3af:ffff:ffff:ffff:ffff:ffff:ffff
60ff89:3b0::/28ff89:3bf:ffff:ffff:ffff:ffff:ffff:ffff
61ff89:3c0::/28ff89:3cf:ffff:ffff:ffff:ffff:ffff:ffff
62ff89:3d0::/28ff89:3df:ffff:ffff:ffff:ffff:ffff:ffff
63ff89:3e0::/28ff89:3ef:ffff:ffff:ffff:ffff:ffff:ffff
64ff89:3f0::/28ff89:3ff:ffff:ffff:ffff:ffff:ffff:ffff
65ff89:400::/28ff89:40f:ffff:ffff:ffff:ffff:ffff:ffff
66ff89:410::/28ff89:41f:ffff:ffff:ffff:ffff:ffff:ffff
67ff89:420::/28ff89:42f:ffff:ffff:ffff:ffff:ffff:ffff
68ff89:430::/28ff89:43f:ffff:ffff:ffff:ffff:ffff:ffff
69ff89:440::/28ff89:44f:ffff:ffff:ffff:ffff:ffff:ffff
70ff89:450::/28ff89:45f:ffff:ffff:ffff:ffff:ffff:ffff
71ff89:460::/28ff89:46f:ffff:ffff:ffff:ffff:ffff:ffff
72ff89:470::/28ff89:47f:ffff:ffff:ffff:ffff:ffff:ffff
73ff89:480::/28ff89:48f:ffff:ffff:ffff:ffff:ffff:ffff
74ff89:490::/28ff89:49f:ffff:ffff:ffff:ffff:ffff:ffff
75ff89:4a0::/28ff89:4af:ffff:ffff:ffff:ffff:ffff:ffff
76ff89:4b0::/28ff89:4bf:ffff:ffff:ffff:ffff:ffff:ffff
77ff89:4c0::/28ff89:4cf:ffff:ffff:ffff:ffff:ffff:ffff
78ff89:4d0::/28ff89:4df:ffff:ffff:ffff:ffff:ffff:ffff
79ff89:4e0::/28ff89:4ef:ffff:ffff:ffff:ffff:ffff:ffff
80ff89:4f0::/28ff89:4ff:ffff:ffff:ffff:ffff:ffff:ffff
81ff89:500::/28ff89:50f:ffff:ffff:ffff:ffff:ffff:ffff
82ff89:510::/28ff89:51f:ffff:ffff:ffff:ffff:ffff:ffff
83ff89:520::/28ff89:52f:ffff:ffff:ffff:ffff:ffff:ffff
84ff89:530::/28ff89:53f:ffff:ffff:ffff:ffff:ffff:ffff
85ff89:540::/28ff89:54f:ffff:ffff:ffff:ffff:ffff:ffff
86ff89:550::/28ff89:55f:ffff:ffff:ffff:ffff:ffff:ffff
87ff89:560::/28ff89:56f:ffff:ffff:ffff:ffff:ffff:ffff
88ff89:570::/28ff89:57f:ffff:ffff:ffff:ffff:ffff:ffff
89ff89:580::/28ff89:58f:ffff:ffff:ffff:ffff:ffff:ffff
90ff89:590::/28ff89:59f:ffff:ffff:ffff:ffff:ffff:ffff
91ff89:5a0::/28ff89:5af:ffff:ffff:ffff:ffff:ffff:ffff
92ff89:5b0::/28ff89:5bf:ffff:ffff:ffff:ffff:ffff:ffff
93ff89:5c0::/28ff89:5cf:ffff:ffff:ffff:ffff:ffff:ffff
94ff89:5d0::/28ff89:5df:ffff:ffff:ffff:ffff:ffff:ffff
95ff89:5e0::/28ff89:5ef:ffff:ffff:ffff:ffff:ffff:ffff
96ff89:5f0::/28ff89:5ff:ffff:ffff:ffff:ffff:ffff:ffff
97ff89:600::/28ff89:60f:ffff:ffff:ffff:ffff:ffff:ffff
98ff89:610::/28ff89:61f:ffff:ffff:ffff:ffff:ffff:ffff
99ff89:620::/28ff89:62f:ffff:ffff:ffff:ffff:ffff:ffff
100ff89:630::/28ff89:63f:ffff:ffff:ffff:ffff:ffff:ffff
101ff89:640::/28ff89:64f:ffff:ffff:ffff:ffff:ffff:ffff
102ff89:650::/28ff89:65f:ffff:ffff:ffff:ffff:ffff:ffff
103ff89:660::/28ff89:66f:ffff:ffff:ffff:ffff:ffff:ffff
104ff89:670::/28ff89:67f:ffff:ffff:ffff:ffff:ffff:ffff
105ff89:680::/28ff89:68f:ffff:ffff:ffff:ffff:ffff:ffff
106ff89:690::/28ff89:69f:ffff:ffff:ffff:ffff:ffff:ffff
107ff89:6a0::/28ff89:6af:ffff:ffff:ffff:ffff:ffff:ffff
108ff89:6b0::/28ff89:6bf:ffff:ffff:ffff:ffff:ffff:ffff
109ff89:6c0::/28ff89:6cf:ffff:ffff:ffff:ffff:ffff:ffff
110ff89:6d0::/28ff89:6df:ffff:ffff:ffff:ffff:ffff:ffff
111ff89:6e0::/28ff89:6ef:ffff:ffff:ffff:ffff:ffff:ffff
112ff89:6f0::/28ff89:6ff:ffff:ffff:ffff:ffff:ffff:ffff
113ff89:700::/28ff89:70f:ffff:ffff:ffff:ffff:ffff:ffff
114ff89:710::/28ff89:71f:ffff:ffff:ffff:ffff:ffff:ffff
115ff89:720::/28ff89:72f:ffff:ffff:ffff:ffff:ffff:ffff
116ff89:730::/28ff89:73f:ffff:ffff:ffff:ffff:ffff:ffff
117ff89:740::/28ff89:74f:ffff:ffff:ffff:ffff:ffff:ffff
118ff89:750::/28ff89:75f:ffff:ffff:ffff:ffff:ffff:ffff
119ff89:760::/28ff89:76f:ffff:ffff:ffff:ffff:ffff:ffff
120ff89:770::/28ff89:77f:ffff:ffff:ffff:ffff:ffff:ffff
121ff89:780::/28ff89:78f:ffff:ffff:ffff:ffff:ffff:ffff
122ff89:790::/28ff89:79f:ffff:ffff:ffff:ffff:ffff:ffff
123ff89:7a0::/28ff89:7af:ffff:ffff:ffff:ffff:ffff:ffff
124ff89:7b0::/28ff89:7bf:ffff:ffff:ffff:ffff:ffff:ffff
125ff89:7c0::/28ff89:7cf:ffff:ffff:ffff:ffff:ffff:ffff
126ff89:7d0::/28ff89:7df:ffff:ffff:ffff:ffff:ffff:ffff
127ff89:7e0::/28ff89:7ef:ffff:ffff:ffff:ffff:ffff:ffff
128ff89:7f0::/28ff89:7ff:ffff:ffff:ffff:ffff:ffff:ffff
129ff89:800::/28ff89:80f:ffff:ffff:ffff:ffff:ffff:ffff
130ff89:810::/28ff89:81f:ffff:ffff:ffff:ffff:ffff:ffff
131ff89:820::/28ff89:82f:ffff:ffff:ffff:ffff:ffff:ffff
132ff89:830::/28ff89:83f:ffff:ffff:ffff:ffff:ffff:ffff
133ff89:840::/28ff89:84f:ffff:ffff:ffff:ffff:ffff:ffff
134ff89:850::/28ff89:85f:ffff:ffff:ffff:ffff:ffff:ffff
135ff89:860::/28ff89:86f:ffff:ffff:ffff:ffff:ffff:ffff
136ff89:870::/28ff89:87f:ffff:ffff:ffff:ffff:ffff:ffff
137ff89:880::/28ff89:88f:ffff:ffff:ffff:ffff:ffff:ffff
138ff89:890::/28ff89:89f:ffff:ffff:ffff:ffff:ffff:ffff
139ff89:8a0::/28ff89:8af:ffff:ffff:ffff:ffff:ffff:ffff
140ff89:8b0::/28ff89:8bf:ffff:ffff:ffff:ffff:ffff:ffff
141ff89:8c0::/28ff89:8cf:ffff:ffff:ffff:ffff:ffff:ffff
142ff89:8d0::/28ff89:8df:ffff:ffff:ffff:ffff:ffff:ffff
143ff89:8e0::/28ff89:8ef:ffff:ffff:ffff:ffff:ffff:ffff
144ff89:8f0::/28ff89:8ff:ffff:ffff:ffff:ffff:ffff:ffff
145ff89:900::/28ff89:90f:ffff:ffff:ffff:ffff:ffff:ffff
146ff89:910::/28ff89:91f:ffff:ffff:ffff:ffff:ffff:ffff
147ff89:920::/28ff89:92f:ffff:ffff:ffff:ffff:ffff:ffff
148ff89:930::/28ff89:93f:ffff:ffff:ffff:ffff:ffff:ffff
149ff89:940::/28ff89:94f:ffff:ffff:ffff:ffff:ffff:ffff
150ff89:950::/28ff89:95f:ffff:ffff:ffff:ffff:ffff:ffff
151ff89:960::/28ff89:96f:ffff:ffff:ffff:ffff:ffff:ffff
152ff89:970::/28ff89:97f:ffff:ffff:ffff:ffff:ffff:ffff
153ff89:980::/28ff89:98f:ffff:ffff:ffff:ffff:ffff:ffff
154ff89:990::/28ff89:99f:ffff:ffff:ffff:ffff:ffff:ffff
155ff89:9a0::/28ff89:9af:ffff:ffff:ffff:ffff:ffff:ffff
156ff89:9b0::/28ff89:9bf:ffff:ffff:ffff:ffff:ffff:ffff
157ff89:9c0::/28ff89:9cf:ffff:ffff:ffff:ffff:ffff:ffff
158ff89:9d0::/28ff89:9df:ffff:ffff:ffff:ffff:ffff:ffff
159ff89:9e0::/28ff89:9ef:ffff:ffff:ffff:ffff:ffff:ffff
160ff89:9f0::/28ff89:9ff:ffff:ffff:ffff:ffff:ffff:ffff
161ff89:a00::/28ff89:a0f:ffff:ffff:ffff:ffff:ffff:ffff
162ff89:a10::/28ff89:a1f:ffff:ffff:ffff:ffff:ffff:ffff
163ff89:a20::/28ff89:a2f:ffff:ffff:ffff:ffff:ffff:ffff
164ff89:a30::/28ff89:a3f:ffff:ffff:ffff:ffff:ffff:ffff
165ff89:a40::/28ff89:a4f:ffff:ffff:ffff:ffff:ffff:ffff
166ff89:a50::/28ff89:a5f:ffff:ffff:ffff:ffff:ffff:ffff
167ff89:a60::/28ff89:a6f:ffff:ffff:ffff:ffff:ffff:ffff
168ff89:a70::/28ff89:a7f:ffff:ffff:ffff:ffff:ffff:ffff
169ff89:a80::/28ff89:a8f:ffff:ffff:ffff:ffff:ffff:ffff
170ff89:a90::/28ff89:a9f:ffff:ffff:ffff:ffff:ffff:ffff
171ff89:aa0::/28ff89:aaf:ffff:ffff:ffff:ffff:ffff:ffff
172ff89:ab0::/28ff89:abf:ffff:ffff:ffff:ffff:ffff:ffff
173ff89:ac0::/28ff89:acf:ffff:ffff:ffff:ffff:ffff:ffff
174ff89:ad0::/28ff89:adf:ffff:ffff:ffff:ffff:ffff:ffff
175ff89:ae0::/28ff89:aef:ffff:ffff:ffff:ffff:ffff:ffff
176ff89:af0::/28ff89:aff:ffff:ffff:ffff:ffff:ffff:ffff
177ff89:b00::/28ff89:b0f:ffff:ffff:ffff:ffff:ffff:ffff
178ff89:b10::/28ff89:b1f:ffff:ffff:ffff:ffff:ffff:ffff
179ff89:b20::/28ff89:b2f:ffff:ffff:ffff:ffff:ffff:ffff
180ff89:b30::/28ff89:b3f:ffff:ffff:ffff:ffff:ffff:ffff
181ff89:b40::/28ff89:b4f:ffff:ffff:ffff:ffff:ffff:ffff
182ff89:b50::/28ff89:b5f:ffff:ffff:ffff:ffff:ffff:ffff
183ff89:b60::/28ff89:b6f:ffff:ffff:ffff:ffff:ffff:ffff
184ff89:b70::/28ff89:b7f:ffff:ffff:ffff:ffff:ffff:ffff
185ff89:b80::/28ff89:b8f:ffff:ffff:ffff:ffff:ffff:ffff
186ff89:b90::/28ff89:b9f:ffff:ffff:ffff:ffff:ffff:ffff
187ff89:ba0::/28ff89:baf:ffff:ffff:ffff:ffff:ffff:ffff
188ff89:bb0::/28ff89:bbf:ffff:ffff:ffff:ffff:ffff:ffff
189ff89:bc0::/28ff89:bcf:ffff:ffff:ffff:ffff:ffff:ffff
190ff89:bd0::/28ff89:bdf:ffff:ffff:ffff:ffff:ffff:ffff
191ff89:be0::/28ff89:bef:ffff:ffff:ffff:ffff:ffff:ffff
192ff89:bf0::/28ff89:bff:ffff:ffff:ffff:ffff:ffff:ffff
193ff89:c00::/28ff89:c0f:ffff:ffff:ffff:ffff:ffff:ffff
194ff89:c10::/28ff89:c1f:ffff:ffff:ffff:ffff:ffff:ffff
195ff89:c20::/28ff89:c2f:ffff:ffff:ffff:ffff:ffff:ffff
196ff89:c30::/28ff89:c3f:ffff:ffff:ffff:ffff:ffff:ffff
197ff89:c40::/28ff89:c4f:ffff:ffff:ffff:ffff:ffff:ffff
198ff89:c50::/28ff89:c5f:ffff:ffff:ffff:ffff:ffff:ffff
199ff89:c60::/28ff89:c6f:ffff:ffff:ffff:ffff:ffff:ffff
200ff89:c70::/28ff89:c7f:ffff:ffff:ffff:ffff:ffff:ffff
201ff89:c80::/28ff89:c8f:ffff:ffff:ffff:ffff:ffff:ffff
202ff89:c90::/28ff89:c9f:ffff:ffff:ffff:ffff:ffff:ffff
203ff89:ca0::/28ff89:caf:ffff:ffff:ffff:ffff:ffff:ffff
204ff89:cb0::/28ff89:cbf:ffff:ffff:ffff:ffff:ffff:ffff
205ff89:cc0::/28ff89:ccf:ffff:ffff:ffff:ffff:ffff:ffff
206ff89:cd0::/28ff89:cdf:ffff:ffff:ffff:ffff:ffff:ffff
207ff89:ce0::/28ff89:cef:ffff:ffff:ffff:ffff:ffff:ffff
208ff89:cf0::/28ff89:cff:ffff:ffff:ffff:ffff:ffff:ffff
209ff89:d00::/28ff89:d0f:ffff:ffff:ffff:ffff:ffff:ffff
210ff89:d10::/28ff89:d1f:ffff:ffff:ffff:ffff:ffff:ffff
211ff89:d20::/28ff89:d2f:ffff:ffff:ffff:ffff:ffff:ffff
212ff89:d30::/28ff89:d3f:ffff:ffff:ffff:ffff:ffff:ffff
213ff89:d40::/28ff89:d4f:ffff:ffff:ffff:ffff:ffff:ffff
214ff89:d50::/28ff89:d5f:ffff:ffff:ffff:ffff:ffff:ffff
215ff89:d60::/28ff89:d6f:ffff:ffff:ffff:ffff:ffff:ffff
216ff89:d70::/28ff89:d7f:ffff:ffff:ffff:ffff:ffff:ffff
217ff89:d80::/28ff89:d8f:ffff:ffff:ffff:ffff:ffff:ffff
218ff89:d90::/28ff89:d9f:ffff:ffff:ffff:ffff:ffff:ffff
219ff89:da0::/28ff89:daf:ffff:ffff:ffff:ffff:ffff:ffff
220ff89:db0::/28ff89:dbf:ffff:ffff:ffff:ffff:ffff:ffff
221ff89:dc0::/28ff89:dcf:ffff:ffff:ffff:ffff:ffff:ffff
222ff89:dd0::/28ff89:ddf:ffff:ffff:ffff:ffff:ffff:ffff
223ff89:de0::/28ff89:def:ffff:ffff:ffff:ffff:ffff:ffff
224ff89:df0::/28ff89:dff:ffff:ffff:ffff:ffff:ffff:ffff
225ff89:e00::/28ff89:e0f:ffff:ffff:ffff:ffff:ffff:ffff
226ff89:e10::/28ff89:e1f:ffff:ffff:ffff:ffff:ffff:ffff
227ff89:e20::/28ff89:e2f:ffff:ffff:ffff:ffff:ffff:ffff
228ff89:e30::/28ff89:e3f:ffff:ffff:ffff:ffff:ffff:ffff
229ff89:e40::/28ff89:e4f:ffff:ffff:ffff:ffff:ffff:ffff
230ff89:e50::/28ff89:e5f:ffff:ffff:ffff:ffff:ffff:ffff
231ff89:e60::/28ff89:e6f:ffff:ffff:ffff:ffff:ffff:ffff
232ff89:e70::/28ff89:e7f:ffff:ffff:ffff:ffff:ffff:ffff
233ff89:e80::/28ff89:e8f:ffff:ffff:ffff:ffff:ffff:ffff
234ff89:e90::/28ff89:e9f:ffff:ffff:ffff:ffff:ffff:ffff
235ff89:ea0::/28ff89:eaf:ffff:ffff:ffff:ffff:ffff:ffff
236ff89:eb0::/28ff89:ebf:ffff:ffff:ffff:ffff:ffff:ffff
237ff89:ec0::/28ff89:ecf:ffff:ffff:ffff:ffff:ffff:ffff
238ff89:ed0::/28ff89:edf:ffff:ffff:ffff:ffff:ffff:ffff
239ff89:ee0::/28ff89:eef:ffff:ffff:ffff:ffff:ffff:ffff
240ff89:ef0::/28ff89:eff:ffff:ffff:ffff:ffff:ffff:ffff
241ff89:f00::/28ff89:f0f:ffff:ffff:ffff:ffff:ffff:ffff
242ff89:f10::/28ff89:f1f:ffff:ffff:ffff:ffff:ffff:ffff
243ff89:f20::/28ff89:f2f:ffff:ffff:ffff:ffff:ffff:ffff
244ff89:f30::/28ff89:f3f:ffff:ffff:ffff:ffff:ffff:ffff
245ff89:f40::/28ff89:f4f:ffff:ffff:ffff:ffff:ffff:ffff
246ff89:f50::/28ff89:f5f:ffff:ffff:ffff:ffff:ffff:ffff
247ff89:f60::/28ff89:f6f:ffff:ffff:ffff:ffff:ffff:ffff
248ff89:f70::/28ff89:f7f:ffff:ffff:ffff:ffff:ffff:ffff
249ff89:f80::/28ff89:f8f:ffff:ffff:ffff:ffff:ffff:ffff
250ff89:f90::/28ff89:f9f:ffff:ffff:ffff:ffff:ffff:ffff
251ff89:fa0::/28ff89:faf:ffff:ffff:ffff:ffff:ffff:ffff
252ff89:fb0::/28ff89:fbf:ffff:ffff:ffff:ffff:ffff:ffff
253ff89:fc0::/28ff89:fcf:ffff:ffff:ffff:ffff:ffff:ffff
254ff89:fd0::/28ff89:fdf:ffff:ffff:ffff:ffff:ffff:ffff
255ff89:fe0::/28ff89:fef:ffff:ffff:ffff:ffff:ffff:ffff
256ff89:ff0::/28ff89: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.