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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
ff35::/16
First address
ff35::
Last address
ff35: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
ff35:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
5.3.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)

ff35::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
1ff35::/28ff35:f:ffff:ffff:ffff:ffff:ffff:ffff
2ff35:10::/28ff35:1f:ffff:ffff:ffff:ffff:ffff:ffff
3ff35:20::/28ff35:2f:ffff:ffff:ffff:ffff:ffff:ffff
4ff35:30::/28ff35:3f:ffff:ffff:ffff:ffff:ffff:ffff
5ff35:40::/28ff35:4f:ffff:ffff:ffff:ffff:ffff:ffff
6ff35:50::/28ff35:5f:ffff:ffff:ffff:ffff:ffff:ffff
7ff35:60::/28ff35:6f:ffff:ffff:ffff:ffff:ffff:ffff
8ff35:70::/28ff35:7f:ffff:ffff:ffff:ffff:ffff:ffff
9ff35:80::/28ff35:8f:ffff:ffff:ffff:ffff:ffff:ffff
10ff35:90::/28ff35:9f:ffff:ffff:ffff:ffff:ffff:ffff
11ff35:a0::/28ff35:af:ffff:ffff:ffff:ffff:ffff:ffff
12ff35:b0::/28ff35:bf:ffff:ffff:ffff:ffff:ffff:ffff
13ff35:c0::/28ff35:cf:ffff:ffff:ffff:ffff:ffff:ffff
14ff35:d0::/28ff35:df:ffff:ffff:ffff:ffff:ffff:ffff
15ff35:e0::/28ff35:ef:ffff:ffff:ffff:ffff:ffff:ffff
16ff35:f0::/28ff35:ff:ffff:ffff:ffff:ffff:ffff:ffff
17ff35:100::/28ff35:10f:ffff:ffff:ffff:ffff:ffff:ffff
18ff35:110::/28ff35:11f:ffff:ffff:ffff:ffff:ffff:ffff
19ff35:120::/28ff35:12f:ffff:ffff:ffff:ffff:ffff:ffff
20ff35:130::/28ff35:13f:ffff:ffff:ffff:ffff:ffff:ffff
21ff35:140::/28ff35:14f:ffff:ffff:ffff:ffff:ffff:ffff
22ff35:150::/28ff35:15f:ffff:ffff:ffff:ffff:ffff:ffff
23ff35:160::/28ff35:16f:ffff:ffff:ffff:ffff:ffff:ffff
24ff35:170::/28ff35:17f:ffff:ffff:ffff:ffff:ffff:ffff
25ff35:180::/28ff35:18f:ffff:ffff:ffff:ffff:ffff:ffff
26ff35:190::/28ff35:19f:ffff:ffff:ffff:ffff:ffff:ffff
27ff35:1a0::/28ff35:1af:ffff:ffff:ffff:ffff:ffff:ffff
28ff35:1b0::/28ff35:1bf:ffff:ffff:ffff:ffff:ffff:ffff
29ff35:1c0::/28ff35:1cf:ffff:ffff:ffff:ffff:ffff:ffff
30ff35:1d0::/28ff35:1df:ffff:ffff:ffff:ffff:ffff:ffff
31ff35:1e0::/28ff35:1ef:ffff:ffff:ffff:ffff:ffff:ffff
32ff35:1f0::/28ff35:1ff:ffff:ffff:ffff:ffff:ffff:ffff
33ff35:200::/28ff35:20f:ffff:ffff:ffff:ffff:ffff:ffff
34ff35:210::/28ff35:21f:ffff:ffff:ffff:ffff:ffff:ffff
35ff35:220::/28ff35:22f:ffff:ffff:ffff:ffff:ffff:ffff
36ff35:230::/28ff35:23f:ffff:ffff:ffff:ffff:ffff:ffff
37ff35:240::/28ff35:24f:ffff:ffff:ffff:ffff:ffff:ffff
38ff35:250::/28ff35:25f:ffff:ffff:ffff:ffff:ffff:ffff
39ff35:260::/28ff35:26f:ffff:ffff:ffff:ffff:ffff:ffff
40ff35:270::/28ff35:27f:ffff:ffff:ffff:ffff:ffff:ffff
41ff35:280::/28ff35:28f:ffff:ffff:ffff:ffff:ffff:ffff
42ff35:290::/28ff35:29f:ffff:ffff:ffff:ffff:ffff:ffff
43ff35:2a0::/28ff35:2af:ffff:ffff:ffff:ffff:ffff:ffff
44ff35:2b0::/28ff35:2bf:ffff:ffff:ffff:ffff:ffff:ffff
45ff35:2c0::/28ff35:2cf:ffff:ffff:ffff:ffff:ffff:ffff
46ff35:2d0::/28ff35:2df:ffff:ffff:ffff:ffff:ffff:ffff
47ff35:2e0::/28ff35:2ef:ffff:ffff:ffff:ffff:ffff:ffff
48ff35:2f0::/28ff35:2ff:ffff:ffff:ffff:ffff:ffff:ffff
49ff35:300::/28ff35:30f:ffff:ffff:ffff:ffff:ffff:ffff
50ff35:310::/28ff35:31f:ffff:ffff:ffff:ffff:ffff:ffff
51ff35:320::/28ff35:32f:ffff:ffff:ffff:ffff:ffff:ffff
52ff35:330::/28ff35:33f:ffff:ffff:ffff:ffff:ffff:ffff
53ff35:340::/28ff35:34f:ffff:ffff:ffff:ffff:ffff:ffff
54ff35:350::/28ff35:35f:ffff:ffff:ffff:ffff:ffff:ffff
55ff35:360::/28ff35:36f:ffff:ffff:ffff:ffff:ffff:ffff
56ff35:370::/28ff35:37f:ffff:ffff:ffff:ffff:ffff:ffff
57ff35:380::/28ff35:38f:ffff:ffff:ffff:ffff:ffff:ffff
58ff35:390::/28ff35:39f:ffff:ffff:ffff:ffff:ffff:ffff
59ff35:3a0::/28ff35:3af:ffff:ffff:ffff:ffff:ffff:ffff
60ff35:3b0::/28ff35:3bf:ffff:ffff:ffff:ffff:ffff:ffff
61ff35:3c0::/28ff35:3cf:ffff:ffff:ffff:ffff:ffff:ffff
62ff35:3d0::/28ff35:3df:ffff:ffff:ffff:ffff:ffff:ffff
63ff35:3e0::/28ff35:3ef:ffff:ffff:ffff:ffff:ffff:ffff
64ff35:3f0::/28ff35:3ff:ffff:ffff:ffff:ffff:ffff:ffff
65ff35:400::/28ff35:40f:ffff:ffff:ffff:ffff:ffff:ffff
66ff35:410::/28ff35:41f:ffff:ffff:ffff:ffff:ffff:ffff
67ff35:420::/28ff35:42f:ffff:ffff:ffff:ffff:ffff:ffff
68ff35:430::/28ff35:43f:ffff:ffff:ffff:ffff:ffff:ffff
69ff35:440::/28ff35:44f:ffff:ffff:ffff:ffff:ffff:ffff
70ff35:450::/28ff35:45f:ffff:ffff:ffff:ffff:ffff:ffff
71ff35:460::/28ff35:46f:ffff:ffff:ffff:ffff:ffff:ffff
72ff35:470::/28ff35:47f:ffff:ffff:ffff:ffff:ffff:ffff
73ff35:480::/28ff35:48f:ffff:ffff:ffff:ffff:ffff:ffff
74ff35:490::/28ff35:49f:ffff:ffff:ffff:ffff:ffff:ffff
75ff35:4a0::/28ff35:4af:ffff:ffff:ffff:ffff:ffff:ffff
76ff35:4b0::/28ff35:4bf:ffff:ffff:ffff:ffff:ffff:ffff
77ff35:4c0::/28ff35:4cf:ffff:ffff:ffff:ffff:ffff:ffff
78ff35:4d0::/28ff35:4df:ffff:ffff:ffff:ffff:ffff:ffff
79ff35:4e0::/28ff35:4ef:ffff:ffff:ffff:ffff:ffff:ffff
80ff35:4f0::/28ff35:4ff:ffff:ffff:ffff:ffff:ffff:ffff
81ff35:500::/28ff35:50f:ffff:ffff:ffff:ffff:ffff:ffff
82ff35:510::/28ff35:51f:ffff:ffff:ffff:ffff:ffff:ffff
83ff35:520::/28ff35:52f:ffff:ffff:ffff:ffff:ffff:ffff
84ff35:530::/28ff35:53f:ffff:ffff:ffff:ffff:ffff:ffff
85ff35:540::/28ff35:54f:ffff:ffff:ffff:ffff:ffff:ffff
86ff35:550::/28ff35:55f:ffff:ffff:ffff:ffff:ffff:ffff
87ff35:560::/28ff35:56f:ffff:ffff:ffff:ffff:ffff:ffff
88ff35:570::/28ff35:57f:ffff:ffff:ffff:ffff:ffff:ffff
89ff35:580::/28ff35:58f:ffff:ffff:ffff:ffff:ffff:ffff
90ff35:590::/28ff35:59f:ffff:ffff:ffff:ffff:ffff:ffff
91ff35:5a0::/28ff35:5af:ffff:ffff:ffff:ffff:ffff:ffff
92ff35:5b0::/28ff35:5bf:ffff:ffff:ffff:ffff:ffff:ffff
93ff35:5c0::/28ff35:5cf:ffff:ffff:ffff:ffff:ffff:ffff
94ff35:5d0::/28ff35:5df:ffff:ffff:ffff:ffff:ffff:ffff
95ff35:5e0::/28ff35:5ef:ffff:ffff:ffff:ffff:ffff:ffff
96ff35:5f0::/28ff35:5ff:ffff:ffff:ffff:ffff:ffff:ffff
97ff35:600::/28ff35:60f:ffff:ffff:ffff:ffff:ffff:ffff
98ff35:610::/28ff35:61f:ffff:ffff:ffff:ffff:ffff:ffff
99ff35:620::/28ff35:62f:ffff:ffff:ffff:ffff:ffff:ffff
100ff35:630::/28ff35:63f:ffff:ffff:ffff:ffff:ffff:ffff
101ff35:640::/28ff35:64f:ffff:ffff:ffff:ffff:ffff:ffff
102ff35:650::/28ff35:65f:ffff:ffff:ffff:ffff:ffff:ffff
103ff35:660::/28ff35:66f:ffff:ffff:ffff:ffff:ffff:ffff
104ff35:670::/28ff35:67f:ffff:ffff:ffff:ffff:ffff:ffff
105ff35:680::/28ff35:68f:ffff:ffff:ffff:ffff:ffff:ffff
106ff35:690::/28ff35:69f:ffff:ffff:ffff:ffff:ffff:ffff
107ff35:6a0::/28ff35:6af:ffff:ffff:ffff:ffff:ffff:ffff
108ff35:6b0::/28ff35:6bf:ffff:ffff:ffff:ffff:ffff:ffff
109ff35:6c0::/28ff35:6cf:ffff:ffff:ffff:ffff:ffff:ffff
110ff35:6d0::/28ff35:6df:ffff:ffff:ffff:ffff:ffff:ffff
111ff35:6e0::/28ff35:6ef:ffff:ffff:ffff:ffff:ffff:ffff
112ff35:6f0::/28ff35:6ff:ffff:ffff:ffff:ffff:ffff:ffff
113ff35:700::/28ff35:70f:ffff:ffff:ffff:ffff:ffff:ffff
114ff35:710::/28ff35:71f:ffff:ffff:ffff:ffff:ffff:ffff
115ff35:720::/28ff35:72f:ffff:ffff:ffff:ffff:ffff:ffff
116ff35:730::/28ff35:73f:ffff:ffff:ffff:ffff:ffff:ffff
117ff35:740::/28ff35:74f:ffff:ffff:ffff:ffff:ffff:ffff
118ff35:750::/28ff35:75f:ffff:ffff:ffff:ffff:ffff:ffff
119ff35:760::/28ff35:76f:ffff:ffff:ffff:ffff:ffff:ffff
120ff35:770::/28ff35:77f:ffff:ffff:ffff:ffff:ffff:ffff
121ff35:780::/28ff35:78f:ffff:ffff:ffff:ffff:ffff:ffff
122ff35:790::/28ff35:79f:ffff:ffff:ffff:ffff:ffff:ffff
123ff35:7a0::/28ff35:7af:ffff:ffff:ffff:ffff:ffff:ffff
124ff35:7b0::/28ff35:7bf:ffff:ffff:ffff:ffff:ffff:ffff
125ff35:7c0::/28ff35:7cf:ffff:ffff:ffff:ffff:ffff:ffff
126ff35:7d0::/28ff35:7df:ffff:ffff:ffff:ffff:ffff:ffff
127ff35:7e0::/28ff35:7ef:ffff:ffff:ffff:ffff:ffff:ffff
128ff35:7f0::/28ff35:7ff:ffff:ffff:ffff:ffff:ffff:ffff
129ff35:800::/28ff35:80f:ffff:ffff:ffff:ffff:ffff:ffff
130ff35:810::/28ff35:81f:ffff:ffff:ffff:ffff:ffff:ffff
131ff35:820::/28ff35:82f:ffff:ffff:ffff:ffff:ffff:ffff
132ff35:830::/28ff35:83f:ffff:ffff:ffff:ffff:ffff:ffff
133ff35:840::/28ff35:84f:ffff:ffff:ffff:ffff:ffff:ffff
134ff35:850::/28ff35:85f:ffff:ffff:ffff:ffff:ffff:ffff
135ff35:860::/28ff35:86f:ffff:ffff:ffff:ffff:ffff:ffff
136ff35:870::/28ff35:87f:ffff:ffff:ffff:ffff:ffff:ffff
137ff35:880::/28ff35:88f:ffff:ffff:ffff:ffff:ffff:ffff
138ff35:890::/28ff35:89f:ffff:ffff:ffff:ffff:ffff:ffff
139ff35:8a0::/28ff35:8af:ffff:ffff:ffff:ffff:ffff:ffff
140ff35:8b0::/28ff35:8bf:ffff:ffff:ffff:ffff:ffff:ffff
141ff35:8c0::/28ff35:8cf:ffff:ffff:ffff:ffff:ffff:ffff
142ff35:8d0::/28ff35:8df:ffff:ffff:ffff:ffff:ffff:ffff
143ff35:8e0::/28ff35:8ef:ffff:ffff:ffff:ffff:ffff:ffff
144ff35:8f0::/28ff35:8ff:ffff:ffff:ffff:ffff:ffff:ffff
145ff35:900::/28ff35:90f:ffff:ffff:ffff:ffff:ffff:ffff
146ff35:910::/28ff35:91f:ffff:ffff:ffff:ffff:ffff:ffff
147ff35:920::/28ff35:92f:ffff:ffff:ffff:ffff:ffff:ffff
148ff35:930::/28ff35:93f:ffff:ffff:ffff:ffff:ffff:ffff
149ff35:940::/28ff35:94f:ffff:ffff:ffff:ffff:ffff:ffff
150ff35:950::/28ff35:95f:ffff:ffff:ffff:ffff:ffff:ffff
151ff35:960::/28ff35:96f:ffff:ffff:ffff:ffff:ffff:ffff
152ff35:970::/28ff35:97f:ffff:ffff:ffff:ffff:ffff:ffff
153ff35:980::/28ff35:98f:ffff:ffff:ffff:ffff:ffff:ffff
154ff35:990::/28ff35:99f:ffff:ffff:ffff:ffff:ffff:ffff
155ff35:9a0::/28ff35:9af:ffff:ffff:ffff:ffff:ffff:ffff
156ff35:9b0::/28ff35:9bf:ffff:ffff:ffff:ffff:ffff:ffff
157ff35:9c0::/28ff35:9cf:ffff:ffff:ffff:ffff:ffff:ffff
158ff35:9d0::/28ff35:9df:ffff:ffff:ffff:ffff:ffff:ffff
159ff35:9e0::/28ff35:9ef:ffff:ffff:ffff:ffff:ffff:ffff
160ff35:9f0::/28ff35:9ff:ffff:ffff:ffff:ffff:ffff:ffff
161ff35:a00::/28ff35:a0f:ffff:ffff:ffff:ffff:ffff:ffff
162ff35:a10::/28ff35:a1f:ffff:ffff:ffff:ffff:ffff:ffff
163ff35:a20::/28ff35:a2f:ffff:ffff:ffff:ffff:ffff:ffff
164ff35:a30::/28ff35:a3f:ffff:ffff:ffff:ffff:ffff:ffff
165ff35:a40::/28ff35:a4f:ffff:ffff:ffff:ffff:ffff:ffff
166ff35:a50::/28ff35:a5f:ffff:ffff:ffff:ffff:ffff:ffff
167ff35:a60::/28ff35:a6f:ffff:ffff:ffff:ffff:ffff:ffff
168ff35:a70::/28ff35:a7f:ffff:ffff:ffff:ffff:ffff:ffff
169ff35:a80::/28ff35:a8f:ffff:ffff:ffff:ffff:ffff:ffff
170ff35:a90::/28ff35:a9f:ffff:ffff:ffff:ffff:ffff:ffff
171ff35:aa0::/28ff35:aaf:ffff:ffff:ffff:ffff:ffff:ffff
172ff35:ab0::/28ff35:abf:ffff:ffff:ffff:ffff:ffff:ffff
173ff35:ac0::/28ff35:acf:ffff:ffff:ffff:ffff:ffff:ffff
174ff35:ad0::/28ff35:adf:ffff:ffff:ffff:ffff:ffff:ffff
175ff35:ae0::/28ff35:aef:ffff:ffff:ffff:ffff:ffff:ffff
176ff35:af0::/28ff35:aff:ffff:ffff:ffff:ffff:ffff:ffff
177ff35:b00::/28ff35:b0f:ffff:ffff:ffff:ffff:ffff:ffff
178ff35:b10::/28ff35:b1f:ffff:ffff:ffff:ffff:ffff:ffff
179ff35:b20::/28ff35:b2f:ffff:ffff:ffff:ffff:ffff:ffff
180ff35:b30::/28ff35:b3f:ffff:ffff:ffff:ffff:ffff:ffff
181ff35:b40::/28ff35:b4f:ffff:ffff:ffff:ffff:ffff:ffff
182ff35:b50::/28ff35:b5f:ffff:ffff:ffff:ffff:ffff:ffff
183ff35:b60::/28ff35:b6f:ffff:ffff:ffff:ffff:ffff:ffff
184ff35:b70::/28ff35:b7f:ffff:ffff:ffff:ffff:ffff:ffff
185ff35:b80::/28ff35:b8f:ffff:ffff:ffff:ffff:ffff:ffff
186ff35:b90::/28ff35:b9f:ffff:ffff:ffff:ffff:ffff:ffff
187ff35:ba0::/28ff35:baf:ffff:ffff:ffff:ffff:ffff:ffff
188ff35:bb0::/28ff35:bbf:ffff:ffff:ffff:ffff:ffff:ffff
189ff35:bc0::/28ff35:bcf:ffff:ffff:ffff:ffff:ffff:ffff
190ff35:bd0::/28ff35:bdf:ffff:ffff:ffff:ffff:ffff:ffff
191ff35:be0::/28ff35:bef:ffff:ffff:ffff:ffff:ffff:ffff
192ff35:bf0::/28ff35:bff:ffff:ffff:ffff:ffff:ffff:ffff
193ff35:c00::/28ff35:c0f:ffff:ffff:ffff:ffff:ffff:ffff
194ff35:c10::/28ff35:c1f:ffff:ffff:ffff:ffff:ffff:ffff
195ff35:c20::/28ff35:c2f:ffff:ffff:ffff:ffff:ffff:ffff
196ff35:c30::/28ff35:c3f:ffff:ffff:ffff:ffff:ffff:ffff
197ff35:c40::/28ff35:c4f:ffff:ffff:ffff:ffff:ffff:ffff
198ff35:c50::/28ff35:c5f:ffff:ffff:ffff:ffff:ffff:ffff
199ff35:c60::/28ff35:c6f:ffff:ffff:ffff:ffff:ffff:ffff
200ff35:c70::/28ff35:c7f:ffff:ffff:ffff:ffff:ffff:ffff
201ff35:c80::/28ff35:c8f:ffff:ffff:ffff:ffff:ffff:ffff
202ff35:c90::/28ff35:c9f:ffff:ffff:ffff:ffff:ffff:ffff
203ff35:ca0::/28ff35:caf:ffff:ffff:ffff:ffff:ffff:ffff
204ff35:cb0::/28ff35:cbf:ffff:ffff:ffff:ffff:ffff:ffff
205ff35:cc0::/28ff35:ccf:ffff:ffff:ffff:ffff:ffff:ffff
206ff35:cd0::/28ff35:cdf:ffff:ffff:ffff:ffff:ffff:ffff
207ff35:ce0::/28ff35:cef:ffff:ffff:ffff:ffff:ffff:ffff
208ff35:cf0::/28ff35:cff:ffff:ffff:ffff:ffff:ffff:ffff
209ff35:d00::/28ff35:d0f:ffff:ffff:ffff:ffff:ffff:ffff
210ff35:d10::/28ff35:d1f:ffff:ffff:ffff:ffff:ffff:ffff
211ff35:d20::/28ff35:d2f:ffff:ffff:ffff:ffff:ffff:ffff
212ff35:d30::/28ff35:d3f:ffff:ffff:ffff:ffff:ffff:ffff
213ff35:d40::/28ff35:d4f:ffff:ffff:ffff:ffff:ffff:ffff
214ff35:d50::/28ff35:d5f:ffff:ffff:ffff:ffff:ffff:ffff
215ff35:d60::/28ff35:d6f:ffff:ffff:ffff:ffff:ffff:ffff
216ff35:d70::/28ff35:d7f:ffff:ffff:ffff:ffff:ffff:ffff
217ff35:d80::/28ff35:d8f:ffff:ffff:ffff:ffff:ffff:ffff
218ff35:d90::/28ff35:d9f:ffff:ffff:ffff:ffff:ffff:ffff
219ff35:da0::/28ff35:daf:ffff:ffff:ffff:ffff:ffff:ffff
220ff35:db0::/28ff35:dbf:ffff:ffff:ffff:ffff:ffff:ffff
221ff35:dc0::/28ff35:dcf:ffff:ffff:ffff:ffff:ffff:ffff
222ff35:dd0::/28ff35:ddf:ffff:ffff:ffff:ffff:ffff:ffff
223ff35:de0::/28ff35:def:ffff:ffff:ffff:ffff:ffff:ffff
224ff35:df0::/28ff35:dff:ffff:ffff:ffff:ffff:ffff:ffff
225ff35:e00::/28ff35:e0f:ffff:ffff:ffff:ffff:ffff:ffff
226ff35:e10::/28ff35:e1f:ffff:ffff:ffff:ffff:ffff:ffff
227ff35:e20::/28ff35:e2f:ffff:ffff:ffff:ffff:ffff:ffff
228ff35:e30::/28ff35:e3f:ffff:ffff:ffff:ffff:ffff:ffff
229ff35:e40::/28ff35:e4f:ffff:ffff:ffff:ffff:ffff:ffff
230ff35:e50::/28ff35:e5f:ffff:ffff:ffff:ffff:ffff:ffff
231ff35:e60::/28ff35:e6f:ffff:ffff:ffff:ffff:ffff:ffff
232ff35:e70::/28ff35:e7f:ffff:ffff:ffff:ffff:ffff:ffff
233ff35:e80::/28ff35:e8f:ffff:ffff:ffff:ffff:ffff:ffff
234ff35:e90::/28ff35:e9f:ffff:ffff:ffff:ffff:ffff:ffff
235ff35:ea0::/28ff35:eaf:ffff:ffff:ffff:ffff:ffff:ffff
236ff35:eb0::/28ff35:ebf:ffff:ffff:ffff:ffff:ffff:ffff
237ff35:ec0::/28ff35:ecf:ffff:ffff:ffff:ffff:ffff:ffff
238ff35:ed0::/28ff35:edf:ffff:ffff:ffff:ffff:ffff:ffff
239ff35:ee0::/28ff35:eef:ffff:ffff:ffff:ffff:ffff:ffff
240ff35:ef0::/28ff35:eff:ffff:ffff:ffff:ffff:ffff:ffff
241ff35:f00::/28ff35:f0f:ffff:ffff:ffff:ffff:ffff:ffff
242ff35:f10::/28ff35:f1f:ffff:ffff:ffff:ffff:ffff:ffff
243ff35:f20::/28ff35:f2f:ffff:ffff:ffff:ffff:ffff:ffff
244ff35:f30::/28ff35:f3f:ffff:ffff:ffff:ffff:ffff:ffff
245ff35:f40::/28ff35:f4f:ffff:ffff:ffff:ffff:ffff:ffff
246ff35:f50::/28ff35:f5f:ffff:ffff:ffff:ffff:ffff:ffff
247ff35:f60::/28ff35:f6f:ffff:ffff:ffff:ffff:ffff:ffff
248ff35:f70::/28ff35:f7f:ffff:ffff:ffff:ffff:ffff:ffff
249ff35:f80::/28ff35:f8f:ffff:ffff:ffff:ffff:ffff:ffff
250ff35:f90::/28ff35:f9f:ffff:ffff:ffff:ffff:ffff:ffff
251ff35:fa0::/28ff35:faf:ffff:ffff:ffff:ffff:ffff:ffff
252ff35:fb0::/28ff35:fbf:ffff:ffff:ffff:ffff:ffff:ffff
253ff35:fc0::/28ff35:fcf:ffff:ffff:ffff:ffff:ffff:ffff
254ff35:fd0::/28ff35:fdf:ffff:ffff:ffff:ffff:ffff:ffff
255ff35:fe0::/28ff35:fef:ffff:ffff:ffff:ffff:ffff:ffff
256ff35:ff0::/28ff35: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.