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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/18
Addresses2^110
/64 networks2^46
Network
ff4e::/18
First address
ff4e::
Last address
ff4e:3fff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
1,298,074,214,633,706,907,132,624,082,305,024 (2^110)
/64 networks (LANs)
70,368,744,177,664 (2^46)
Full form
ff4e:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zones
0.e.4.f.f.ip6.arpa
1.e.4.f.f.ip6.arpa
2.e.4.f.f.ip6.arpa
3.e.4.f.f.ip6.arpa
/18 is not on a 4-bit boundary, so it takes 4 /20 zones.
Split into smaller subnets/28
/19 (2)/20 (4)/21 (8)/22 (16)/24 (64)/28 (1,024)/32 (16,384)

ff4e::/18 makes 1,024 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
1ff4e::/28ff4e:f:ffff:ffff:ffff:ffff:ffff:ffff
2ff4e:10::/28ff4e:1f:ffff:ffff:ffff:ffff:ffff:ffff
3ff4e:20::/28ff4e:2f:ffff:ffff:ffff:ffff:ffff:ffff
4ff4e:30::/28ff4e:3f:ffff:ffff:ffff:ffff:ffff:ffff
5ff4e:40::/28ff4e:4f:ffff:ffff:ffff:ffff:ffff:ffff
6ff4e:50::/28ff4e:5f:ffff:ffff:ffff:ffff:ffff:ffff
7ff4e:60::/28ff4e:6f:ffff:ffff:ffff:ffff:ffff:ffff
8ff4e:70::/28ff4e:7f:ffff:ffff:ffff:ffff:ffff:ffff
9ff4e:80::/28ff4e:8f:ffff:ffff:ffff:ffff:ffff:ffff
10ff4e:90::/28ff4e:9f:ffff:ffff:ffff:ffff:ffff:ffff
11ff4e:a0::/28ff4e:af:ffff:ffff:ffff:ffff:ffff:ffff
12ff4e:b0::/28ff4e:bf:ffff:ffff:ffff:ffff:ffff:ffff
13ff4e:c0::/28ff4e:cf:ffff:ffff:ffff:ffff:ffff:ffff
14ff4e:d0::/28ff4e:df:ffff:ffff:ffff:ffff:ffff:ffff
15ff4e:e0::/28ff4e:ef:ffff:ffff:ffff:ffff:ffff:ffff
16ff4e:f0::/28ff4e:ff:ffff:ffff:ffff:ffff:ffff:ffff
17ff4e:100::/28ff4e:10f:ffff:ffff:ffff:ffff:ffff:ffff
18ff4e:110::/28ff4e:11f:ffff:ffff:ffff:ffff:ffff:ffff
19ff4e:120::/28ff4e:12f:ffff:ffff:ffff:ffff:ffff:ffff
20ff4e:130::/28ff4e:13f:ffff:ffff:ffff:ffff:ffff:ffff
21ff4e:140::/28ff4e:14f:ffff:ffff:ffff:ffff:ffff:ffff
22ff4e:150::/28ff4e:15f:ffff:ffff:ffff:ffff:ffff:ffff
23ff4e:160::/28ff4e:16f:ffff:ffff:ffff:ffff:ffff:ffff
24ff4e:170::/28ff4e:17f:ffff:ffff:ffff:ffff:ffff:ffff
25ff4e:180::/28ff4e:18f:ffff:ffff:ffff:ffff:ffff:ffff
26ff4e:190::/28ff4e:19f:ffff:ffff:ffff:ffff:ffff:ffff
27ff4e:1a0::/28ff4e:1af:ffff:ffff:ffff:ffff:ffff:ffff
28ff4e:1b0::/28ff4e:1bf:ffff:ffff:ffff:ffff:ffff:ffff
29ff4e:1c0::/28ff4e:1cf:ffff:ffff:ffff:ffff:ffff:ffff
30ff4e:1d0::/28ff4e:1df:ffff:ffff:ffff:ffff:ffff:ffff
31ff4e:1e0::/28ff4e:1ef:ffff:ffff:ffff:ffff:ffff:ffff
32ff4e:1f0::/28ff4e:1ff:ffff:ffff:ffff:ffff:ffff:ffff
33ff4e:200::/28ff4e:20f:ffff:ffff:ffff:ffff:ffff:ffff
34ff4e:210::/28ff4e:21f:ffff:ffff:ffff:ffff:ffff:ffff
35ff4e:220::/28ff4e:22f:ffff:ffff:ffff:ffff:ffff:ffff
36ff4e:230::/28ff4e:23f:ffff:ffff:ffff:ffff:ffff:ffff
37ff4e:240::/28ff4e:24f:ffff:ffff:ffff:ffff:ffff:ffff
38ff4e:250::/28ff4e:25f:ffff:ffff:ffff:ffff:ffff:ffff
39ff4e:260::/28ff4e:26f:ffff:ffff:ffff:ffff:ffff:ffff
40ff4e:270::/28ff4e:27f:ffff:ffff:ffff:ffff:ffff:ffff
41ff4e:280::/28ff4e:28f:ffff:ffff:ffff:ffff:ffff:ffff
42ff4e:290::/28ff4e:29f:ffff:ffff:ffff:ffff:ffff:ffff
43ff4e:2a0::/28ff4e:2af:ffff:ffff:ffff:ffff:ffff:ffff
44ff4e:2b0::/28ff4e:2bf:ffff:ffff:ffff:ffff:ffff:ffff
45ff4e:2c0::/28ff4e:2cf:ffff:ffff:ffff:ffff:ffff:ffff
46ff4e:2d0::/28ff4e:2df:ffff:ffff:ffff:ffff:ffff:ffff
47ff4e:2e0::/28ff4e:2ef:ffff:ffff:ffff:ffff:ffff:ffff
48ff4e:2f0::/28ff4e:2ff:ffff:ffff:ffff:ffff:ffff:ffff
49ff4e:300::/28ff4e:30f:ffff:ffff:ffff:ffff:ffff:ffff
50ff4e:310::/28ff4e:31f:ffff:ffff:ffff:ffff:ffff:ffff
51ff4e:320::/28ff4e:32f:ffff:ffff:ffff:ffff:ffff:ffff
52ff4e:330::/28ff4e:33f:ffff:ffff:ffff:ffff:ffff:ffff
53ff4e:340::/28ff4e:34f:ffff:ffff:ffff:ffff:ffff:ffff
54ff4e:350::/28ff4e:35f:ffff:ffff:ffff:ffff:ffff:ffff
55ff4e:360::/28ff4e:36f:ffff:ffff:ffff:ffff:ffff:ffff
56ff4e:370::/28ff4e:37f:ffff:ffff:ffff:ffff:ffff:ffff
57ff4e:380::/28ff4e:38f:ffff:ffff:ffff:ffff:ffff:ffff
58ff4e:390::/28ff4e:39f:ffff:ffff:ffff:ffff:ffff:ffff
59ff4e:3a0::/28ff4e:3af:ffff:ffff:ffff:ffff:ffff:ffff
60ff4e:3b0::/28ff4e:3bf:ffff:ffff:ffff:ffff:ffff:ffff
61ff4e:3c0::/28ff4e:3cf:ffff:ffff:ffff:ffff:ffff:ffff
62ff4e:3d0::/28ff4e:3df:ffff:ffff:ffff:ffff:ffff:ffff
63ff4e:3e0::/28ff4e:3ef:ffff:ffff:ffff:ffff:ffff:ffff
64ff4e:3f0::/28ff4e:3ff:ffff:ffff:ffff:ffff:ffff:ffff
65ff4e:400::/28ff4e:40f:ffff:ffff:ffff:ffff:ffff:ffff
66ff4e:410::/28ff4e:41f:ffff:ffff:ffff:ffff:ffff:ffff
67ff4e:420::/28ff4e:42f:ffff:ffff:ffff:ffff:ffff:ffff
68ff4e:430::/28ff4e:43f:ffff:ffff:ffff:ffff:ffff:ffff
69ff4e:440::/28ff4e:44f:ffff:ffff:ffff:ffff:ffff:ffff
70ff4e:450::/28ff4e:45f:ffff:ffff:ffff:ffff:ffff:ffff
71ff4e:460::/28ff4e:46f:ffff:ffff:ffff:ffff:ffff:ffff
72ff4e:470::/28ff4e:47f:ffff:ffff:ffff:ffff:ffff:ffff
73ff4e:480::/28ff4e:48f:ffff:ffff:ffff:ffff:ffff:ffff
74ff4e:490::/28ff4e:49f:ffff:ffff:ffff:ffff:ffff:ffff
75ff4e:4a0::/28ff4e:4af:ffff:ffff:ffff:ffff:ffff:ffff
76ff4e:4b0::/28ff4e:4bf:ffff:ffff:ffff:ffff:ffff:ffff
77ff4e:4c0::/28ff4e:4cf:ffff:ffff:ffff:ffff:ffff:ffff
78ff4e:4d0::/28ff4e:4df:ffff:ffff:ffff:ffff:ffff:ffff
79ff4e:4e0::/28ff4e:4ef:ffff:ffff:ffff:ffff:ffff:ffff
80ff4e:4f0::/28ff4e:4ff:ffff:ffff:ffff:ffff:ffff:ffff
81ff4e:500::/28ff4e:50f:ffff:ffff:ffff:ffff:ffff:ffff
82ff4e:510::/28ff4e:51f:ffff:ffff:ffff:ffff:ffff:ffff
83ff4e:520::/28ff4e:52f:ffff:ffff:ffff:ffff:ffff:ffff
84ff4e:530::/28ff4e:53f:ffff:ffff:ffff:ffff:ffff:ffff
85ff4e:540::/28ff4e:54f:ffff:ffff:ffff:ffff:ffff:ffff
86ff4e:550::/28ff4e:55f:ffff:ffff:ffff:ffff:ffff:ffff
87ff4e:560::/28ff4e:56f:ffff:ffff:ffff:ffff:ffff:ffff
88ff4e:570::/28ff4e:57f:ffff:ffff:ffff:ffff:ffff:ffff
89ff4e:580::/28ff4e:58f:ffff:ffff:ffff:ffff:ffff:ffff
90ff4e:590::/28ff4e:59f:ffff:ffff:ffff:ffff:ffff:ffff
91ff4e:5a0::/28ff4e:5af:ffff:ffff:ffff:ffff:ffff:ffff
92ff4e:5b0::/28ff4e:5bf:ffff:ffff:ffff:ffff:ffff:ffff
93ff4e:5c0::/28ff4e:5cf:ffff:ffff:ffff:ffff:ffff:ffff
94ff4e:5d0::/28ff4e:5df:ffff:ffff:ffff:ffff:ffff:ffff
95ff4e:5e0::/28ff4e:5ef:ffff:ffff:ffff:ffff:ffff:ffff
96ff4e:5f0::/28ff4e:5ff:ffff:ffff:ffff:ffff:ffff:ffff
97ff4e:600::/28ff4e:60f:ffff:ffff:ffff:ffff:ffff:ffff
98ff4e:610::/28ff4e:61f:ffff:ffff:ffff:ffff:ffff:ffff
99ff4e:620::/28ff4e:62f:ffff:ffff:ffff:ffff:ffff:ffff
100ff4e:630::/28ff4e:63f:ffff:ffff:ffff:ffff:ffff:ffff
101ff4e:640::/28ff4e:64f:ffff:ffff:ffff:ffff:ffff:ffff
102ff4e:650::/28ff4e:65f:ffff:ffff:ffff:ffff:ffff:ffff
103ff4e:660::/28ff4e:66f:ffff:ffff:ffff:ffff:ffff:ffff
104ff4e:670::/28ff4e:67f:ffff:ffff:ffff:ffff:ffff:ffff
105ff4e:680::/28ff4e:68f:ffff:ffff:ffff:ffff:ffff:ffff
106ff4e:690::/28ff4e:69f:ffff:ffff:ffff:ffff:ffff:ffff
107ff4e:6a0::/28ff4e:6af:ffff:ffff:ffff:ffff:ffff:ffff
108ff4e:6b0::/28ff4e:6bf:ffff:ffff:ffff:ffff:ffff:ffff
109ff4e:6c0::/28ff4e:6cf:ffff:ffff:ffff:ffff:ffff:ffff
110ff4e:6d0::/28ff4e:6df:ffff:ffff:ffff:ffff:ffff:ffff
111ff4e:6e0::/28ff4e:6ef:ffff:ffff:ffff:ffff:ffff:ffff
112ff4e:6f0::/28ff4e:6ff:ffff:ffff:ffff:ffff:ffff:ffff
113ff4e:700::/28ff4e:70f:ffff:ffff:ffff:ffff:ffff:ffff
114ff4e:710::/28ff4e:71f:ffff:ffff:ffff:ffff:ffff:ffff
115ff4e:720::/28ff4e:72f:ffff:ffff:ffff:ffff:ffff:ffff
116ff4e:730::/28ff4e:73f:ffff:ffff:ffff:ffff:ffff:ffff
117ff4e:740::/28ff4e:74f:ffff:ffff:ffff:ffff:ffff:ffff
118ff4e:750::/28ff4e:75f:ffff:ffff:ffff:ffff:ffff:ffff
119ff4e:760::/28ff4e:76f:ffff:ffff:ffff:ffff:ffff:ffff
120ff4e:770::/28ff4e:77f:ffff:ffff:ffff:ffff:ffff:ffff
121ff4e:780::/28ff4e:78f:ffff:ffff:ffff:ffff:ffff:ffff
122ff4e:790::/28ff4e:79f:ffff:ffff:ffff:ffff:ffff:ffff
123ff4e:7a0::/28ff4e:7af:ffff:ffff:ffff:ffff:ffff:ffff
124ff4e:7b0::/28ff4e:7bf:ffff:ffff:ffff:ffff:ffff:ffff
125ff4e:7c0::/28ff4e:7cf:ffff:ffff:ffff:ffff:ffff:ffff
126ff4e:7d0::/28ff4e:7df:ffff:ffff:ffff:ffff:ffff:ffff
127ff4e:7e0::/28ff4e:7ef:ffff:ffff:ffff:ffff:ffff:ffff
128ff4e:7f0::/28ff4e:7ff:ffff:ffff:ffff:ffff:ffff:ffff
129ff4e:800::/28ff4e:80f:ffff:ffff:ffff:ffff:ffff:ffff
130ff4e:810::/28ff4e:81f:ffff:ffff:ffff:ffff:ffff:ffff
131ff4e:820::/28ff4e:82f:ffff:ffff:ffff:ffff:ffff:ffff
132ff4e:830::/28ff4e:83f:ffff:ffff:ffff:ffff:ffff:ffff
133ff4e:840::/28ff4e:84f:ffff:ffff:ffff:ffff:ffff:ffff
134ff4e:850::/28ff4e:85f:ffff:ffff:ffff:ffff:ffff:ffff
135ff4e:860::/28ff4e:86f:ffff:ffff:ffff:ffff:ffff:ffff
136ff4e:870::/28ff4e:87f:ffff:ffff:ffff:ffff:ffff:ffff
137ff4e:880::/28ff4e:88f:ffff:ffff:ffff:ffff:ffff:ffff
138ff4e:890::/28ff4e:89f:ffff:ffff:ffff:ffff:ffff:ffff
139ff4e:8a0::/28ff4e:8af:ffff:ffff:ffff:ffff:ffff:ffff
140ff4e:8b0::/28ff4e:8bf:ffff:ffff:ffff:ffff:ffff:ffff
141ff4e:8c0::/28ff4e:8cf:ffff:ffff:ffff:ffff:ffff:ffff
142ff4e:8d0::/28ff4e:8df:ffff:ffff:ffff:ffff:ffff:ffff
143ff4e:8e0::/28ff4e:8ef:ffff:ffff:ffff:ffff:ffff:ffff
144ff4e:8f0::/28ff4e:8ff:ffff:ffff:ffff:ffff:ffff:ffff
145ff4e:900::/28ff4e:90f:ffff:ffff:ffff:ffff:ffff:ffff
146ff4e:910::/28ff4e:91f:ffff:ffff:ffff:ffff:ffff:ffff
147ff4e:920::/28ff4e:92f:ffff:ffff:ffff:ffff:ffff:ffff
148ff4e:930::/28ff4e:93f:ffff:ffff:ffff:ffff:ffff:ffff
149ff4e:940::/28ff4e:94f:ffff:ffff:ffff:ffff:ffff:ffff
150ff4e:950::/28ff4e:95f:ffff:ffff:ffff:ffff:ffff:ffff
151ff4e:960::/28ff4e:96f:ffff:ffff:ffff:ffff:ffff:ffff
152ff4e:970::/28ff4e:97f:ffff:ffff:ffff:ffff:ffff:ffff
153ff4e:980::/28ff4e:98f:ffff:ffff:ffff:ffff:ffff:ffff
154ff4e:990::/28ff4e:99f:ffff:ffff:ffff:ffff:ffff:ffff
155ff4e:9a0::/28ff4e:9af:ffff:ffff:ffff:ffff:ffff:ffff
156ff4e:9b0::/28ff4e:9bf:ffff:ffff:ffff:ffff:ffff:ffff
157ff4e:9c0::/28ff4e:9cf:ffff:ffff:ffff:ffff:ffff:ffff
158ff4e:9d0::/28ff4e:9df:ffff:ffff:ffff:ffff:ffff:ffff
159ff4e:9e0::/28ff4e:9ef:ffff:ffff:ffff:ffff:ffff:ffff
160ff4e:9f0::/28ff4e:9ff:ffff:ffff:ffff:ffff:ffff:ffff
161ff4e:a00::/28ff4e:a0f:ffff:ffff:ffff:ffff:ffff:ffff
162ff4e:a10::/28ff4e:a1f:ffff:ffff:ffff:ffff:ffff:ffff
163ff4e:a20::/28ff4e:a2f:ffff:ffff:ffff:ffff:ffff:ffff
164ff4e:a30::/28ff4e:a3f:ffff:ffff:ffff:ffff:ffff:ffff
165ff4e:a40::/28ff4e:a4f:ffff:ffff:ffff:ffff:ffff:ffff
166ff4e:a50::/28ff4e:a5f:ffff:ffff:ffff:ffff:ffff:ffff
167ff4e:a60::/28ff4e:a6f:ffff:ffff:ffff:ffff:ffff:ffff
168ff4e:a70::/28ff4e:a7f:ffff:ffff:ffff:ffff:ffff:ffff
169ff4e:a80::/28ff4e:a8f:ffff:ffff:ffff:ffff:ffff:ffff
170ff4e:a90::/28ff4e:a9f:ffff:ffff:ffff:ffff:ffff:ffff
171ff4e:aa0::/28ff4e:aaf:ffff:ffff:ffff:ffff:ffff:ffff
172ff4e:ab0::/28ff4e:abf:ffff:ffff:ffff:ffff:ffff:ffff
173ff4e:ac0::/28ff4e:acf:ffff:ffff:ffff:ffff:ffff:ffff
174ff4e:ad0::/28ff4e:adf:ffff:ffff:ffff:ffff:ffff:ffff
175ff4e:ae0::/28ff4e:aef:ffff:ffff:ffff:ffff:ffff:ffff
176ff4e:af0::/28ff4e:aff:ffff:ffff:ffff:ffff:ffff:ffff
177ff4e:b00::/28ff4e:b0f:ffff:ffff:ffff:ffff:ffff:ffff
178ff4e:b10::/28ff4e:b1f:ffff:ffff:ffff:ffff:ffff:ffff
179ff4e:b20::/28ff4e:b2f:ffff:ffff:ffff:ffff:ffff:ffff
180ff4e:b30::/28ff4e:b3f:ffff:ffff:ffff:ffff:ffff:ffff
181ff4e:b40::/28ff4e:b4f:ffff:ffff:ffff:ffff:ffff:ffff
182ff4e:b50::/28ff4e:b5f:ffff:ffff:ffff:ffff:ffff:ffff
183ff4e:b60::/28ff4e:b6f:ffff:ffff:ffff:ffff:ffff:ffff
184ff4e:b70::/28ff4e:b7f:ffff:ffff:ffff:ffff:ffff:ffff
185ff4e:b80::/28ff4e:b8f:ffff:ffff:ffff:ffff:ffff:ffff
186ff4e:b90::/28ff4e:b9f:ffff:ffff:ffff:ffff:ffff:ffff
187ff4e:ba0::/28ff4e:baf:ffff:ffff:ffff:ffff:ffff:ffff
188ff4e:bb0::/28ff4e:bbf:ffff:ffff:ffff:ffff:ffff:ffff
189ff4e:bc0::/28ff4e:bcf:ffff:ffff:ffff:ffff:ffff:ffff
190ff4e:bd0::/28ff4e:bdf:ffff:ffff:ffff:ffff:ffff:ffff
191ff4e:be0::/28ff4e:bef:ffff:ffff:ffff:ffff:ffff:ffff
192ff4e:bf0::/28ff4e:bff:ffff:ffff:ffff:ffff:ffff:ffff
193ff4e:c00::/28ff4e:c0f:ffff:ffff:ffff:ffff:ffff:ffff
194ff4e:c10::/28ff4e:c1f:ffff:ffff:ffff:ffff:ffff:ffff
195ff4e:c20::/28ff4e:c2f:ffff:ffff:ffff:ffff:ffff:ffff
196ff4e:c30::/28ff4e:c3f:ffff:ffff:ffff:ffff:ffff:ffff
197ff4e:c40::/28ff4e:c4f:ffff:ffff:ffff:ffff:ffff:ffff
198ff4e:c50::/28ff4e:c5f:ffff:ffff:ffff:ffff:ffff:ffff
199ff4e:c60::/28ff4e:c6f:ffff:ffff:ffff:ffff:ffff:ffff
200ff4e:c70::/28ff4e:c7f:ffff:ffff:ffff:ffff:ffff:ffff
201ff4e:c80::/28ff4e:c8f:ffff:ffff:ffff:ffff:ffff:ffff
202ff4e:c90::/28ff4e:c9f:ffff:ffff:ffff:ffff:ffff:ffff
203ff4e:ca0::/28ff4e:caf:ffff:ffff:ffff:ffff:ffff:ffff
204ff4e:cb0::/28ff4e:cbf:ffff:ffff:ffff:ffff:ffff:ffff
205ff4e:cc0::/28ff4e:ccf:ffff:ffff:ffff:ffff:ffff:ffff
206ff4e:cd0::/28ff4e:cdf:ffff:ffff:ffff:ffff:ffff:ffff
207ff4e:ce0::/28ff4e:cef:ffff:ffff:ffff:ffff:ffff:ffff
208ff4e:cf0::/28ff4e:cff:ffff:ffff:ffff:ffff:ffff:ffff
209ff4e:d00::/28ff4e:d0f:ffff:ffff:ffff:ffff:ffff:ffff
210ff4e:d10::/28ff4e:d1f:ffff:ffff:ffff:ffff:ffff:ffff
211ff4e:d20::/28ff4e:d2f:ffff:ffff:ffff:ffff:ffff:ffff
212ff4e:d30::/28ff4e:d3f:ffff:ffff:ffff:ffff:ffff:ffff
213ff4e:d40::/28ff4e:d4f:ffff:ffff:ffff:ffff:ffff:ffff
214ff4e:d50::/28ff4e:d5f:ffff:ffff:ffff:ffff:ffff:ffff
215ff4e:d60::/28ff4e:d6f:ffff:ffff:ffff:ffff:ffff:ffff
216ff4e:d70::/28ff4e:d7f:ffff:ffff:ffff:ffff:ffff:ffff
217ff4e:d80::/28ff4e:d8f:ffff:ffff:ffff:ffff:ffff:ffff
218ff4e:d90::/28ff4e:d9f:ffff:ffff:ffff:ffff:ffff:ffff
219ff4e:da0::/28ff4e:daf:ffff:ffff:ffff:ffff:ffff:ffff
220ff4e:db0::/28ff4e:dbf:ffff:ffff:ffff:ffff:ffff:ffff
221ff4e:dc0::/28ff4e:dcf:ffff:ffff:ffff:ffff:ffff:ffff
222ff4e:dd0::/28ff4e:ddf:ffff:ffff:ffff:ffff:ffff:ffff
223ff4e:de0::/28ff4e:def:ffff:ffff:ffff:ffff:ffff:ffff
224ff4e:df0::/28ff4e:dff:ffff:ffff:ffff:ffff:ffff:ffff
225ff4e:e00::/28ff4e:e0f:ffff:ffff:ffff:ffff:ffff:ffff
226ff4e:e10::/28ff4e:e1f:ffff:ffff:ffff:ffff:ffff:ffff
227ff4e:e20::/28ff4e:e2f:ffff:ffff:ffff:ffff:ffff:ffff
228ff4e:e30::/28ff4e:e3f:ffff:ffff:ffff:ffff:ffff:ffff
229ff4e:e40::/28ff4e:e4f:ffff:ffff:ffff:ffff:ffff:ffff
230ff4e:e50::/28ff4e:e5f:ffff:ffff:ffff:ffff:ffff:ffff
231ff4e:e60::/28ff4e:e6f:ffff:ffff:ffff:ffff:ffff:ffff
232ff4e:e70::/28ff4e:e7f:ffff:ffff:ffff:ffff:ffff:ffff
233ff4e:e80::/28ff4e:e8f:ffff:ffff:ffff:ffff:ffff:ffff
234ff4e:e90::/28ff4e:e9f:ffff:ffff:ffff:ffff:ffff:ffff
235ff4e:ea0::/28ff4e:eaf:ffff:ffff:ffff:ffff:ffff:ffff
236ff4e:eb0::/28ff4e:ebf:ffff:ffff:ffff:ffff:ffff:ffff
237ff4e:ec0::/28ff4e:ecf:ffff:ffff:ffff:ffff:ffff:ffff
238ff4e:ed0::/28ff4e:edf:ffff:ffff:ffff:ffff:ffff:ffff
239ff4e:ee0::/28ff4e:eef:ffff:ffff:ffff:ffff:ffff:ffff
240ff4e:ef0::/28ff4e:eff:ffff:ffff:ffff:ffff:ffff:ffff
241ff4e:f00::/28ff4e:f0f:ffff:ffff:ffff:ffff:ffff:ffff
242ff4e:f10::/28ff4e:f1f:ffff:ffff:ffff:ffff:ffff:ffff
243ff4e:f20::/28ff4e:f2f:ffff:ffff:ffff:ffff:ffff:ffff
244ff4e:f30::/28ff4e:f3f:ffff:ffff:ffff:ffff:ffff:ffff
245ff4e:f40::/28ff4e:f4f:ffff:ffff:ffff:ffff:ffff:ffff
246ff4e:f50::/28ff4e:f5f:ffff:ffff:ffff:ffff:ffff:ffff
247ff4e:f60::/28ff4e:f6f:ffff:ffff:ffff:ffff:ffff:ffff
248ff4e:f70::/28ff4e:f7f:ffff:ffff:ffff:ffff:ffff:ffff
249ff4e:f80::/28ff4e:f8f:ffff:ffff:ffff:ffff:ffff:ffff
250ff4e:f90::/28ff4e:f9f:ffff:ffff:ffff:ffff:ffff:ffff
251ff4e:fa0::/28ff4e:faf:ffff:ffff:ffff:ffff:ffff:ffff
252ff4e:fb0::/28ff4e:fbf:ffff:ffff:ffff:ffff:ffff:ffff
253ff4e:fc0::/28ff4e:fcf:ffff:ffff:ffff:ffff:ffff:ffff
254ff4e:fd0::/28ff4e:fdf:ffff:ffff:ffff:ffff:ffff:ffff
255ff4e:fe0::/28ff4e:fef:ffff:ffff:ffff:ffff:ffff:ffff
256ff4e:ff0::/28ff4e: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.