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Speed and call quality testTest delay, jitter and speed, with a focus on phone calls.My IP addressYour public IPv4 and IPv6 addresses, provider and address range.WhoIs lookupWho owns a domain or IP address, when it expires, and its DNS.DNS reportEvery DNS record for a domain, with email setup checked.IP subnet calculatorWork out a network's range, mask and hosts, and split it into subnets.

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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/20
Addresses2^108
/64 networks2^44
Network
ff02:c000::/20
First address
ff02:c000::
Last address
ff02:cfff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
324,518,553,658,426,726,783,156,020,576,256 (2^108)
/64 networks (LANs)
17,592,186,044,416 (2^44)
Full form
ff02:c000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
c.2.0.f.f.ip6.arpa
Split into smaller subnets/28
/21 (2)/22 (4)/23 (8)/24 (16)/28 (256)/32 (4,096)/36 (65,536)

ff02:c000::/20 makes 256 subnets of /28.

Subnets
#SubnetLast address
1ff02:c000::/28ff02:c00f:ffff:ffff:ffff:ffff:ffff:ffff
2ff02:c010::/28ff02:c01f:ffff:ffff:ffff:ffff:ffff:ffff
3ff02:c020::/28ff02:c02f:ffff:ffff:ffff:ffff:ffff:ffff
4ff02:c030::/28ff02:c03f:ffff:ffff:ffff:ffff:ffff:ffff
5ff02:c040::/28ff02:c04f:ffff:ffff:ffff:ffff:ffff:ffff
6ff02:c050::/28ff02:c05f:ffff:ffff:ffff:ffff:ffff:ffff
7ff02:c060::/28ff02:c06f:ffff:ffff:ffff:ffff:ffff:ffff
8ff02:c070::/28ff02:c07f:ffff:ffff:ffff:ffff:ffff:ffff
9ff02:c080::/28ff02:c08f:ffff:ffff:ffff:ffff:ffff:ffff
10ff02:c090::/28ff02:c09f:ffff:ffff:ffff:ffff:ffff:ffff
11ff02:c0a0::/28ff02:c0af:ffff:ffff:ffff:ffff:ffff:ffff
12ff02:c0b0::/28ff02:c0bf:ffff:ffff:ffff:ffff:ffff:ffff
13ff02:c0c0::/28ff02:c0cf:ffff:ffff:ffff:ffff:ffff:ffff
14ff02:c0d0::/28ff02:c0df:ffff:ffff:ffff:ffff:ffff:ffff
15ff02:c0e0::/28ff02:c0ef:ffff:ffff:ffff:ffff:ffff:ffff
16ff02:c0f0::/28ff02:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
17ff02:c100::/28ff02:c10f:ffff:ffff:ffff:ffff:ffff:ffff
18ff02:c110::/28ff02:c11f:ffff:ffff:ffff:ffff:ffff:ffff
19ff02:c120::/28ff02:c12f:ffff:ffff:ffff:ffff:ffff:ffff
20ff02:c130::/28ff02:c13f:ffff:ffff:ffff:ffff:ffff:ffff
21ff02:c140::/28ff02:c14f:ffff:ffff:ffff:ffff:ffff:ffff
22ff02:c150::/28ff02:c15f:ffff:ffff:ffff:ffff:ffff:ffff
23ff02:c160::/28ff02:c16f:ffff:ffff:ffff:ffff:ffff:ffff
24ff02:c170::/28ff02:c17f:ffff:ffff:ffff:ffff:ffff:ffff
25ff02:c180::/28ff02:c18f:ffff:ffff:ffff:ffff:ffff:ffff
26ff02:c190::/28ff02:c19f:ffff:ffff:ffff:ffff:ffff:ffff
27ff02:c1a0::/28ff02:c1af:ffff:ffff:ffff:ffff:ffff:ffff
28ff02:c1b0::/28ff02:c1bf:ffff:ffff:ffff:ffff:ffff:ffff
29ff02:c1c0::/28ff02:c1cf:ffff:ffff:ffff:ffff:ffff:ffff
30ff02:c1d0::/28ff02:c1df:ffff:ffff:ffff:ffff:ffff:ffff
31ff02:c1e0::/28ff02:c1ef:ffff:ffff:ffff:ffff:ffff:ffff
32ff02:c1f0::/28ff02:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
33ff02:c200::/28ff02:c20f:ffff:ffff:ffff:ffff:ffff:ffff
34ff02:c210::/28ff02:c21f:ffff:ffff:ffff:ffff:ffff:ffff
35ff02:c220::/28ff02:c22f:ffff:ffff:ffff:ffff:ffff:ffff
36ff02:c230::/28ff02:c23f:ffff:ffff:ffff:ffff:ffff:ffff
37ff02:c240::/28ff02:c24f:ffff:ffff:ffff:ffff:ffff:ffff
38ff02:c250::/28ff02:c25f:ffff:ffff:ffff:ffff:ffff:ffff
39ff02:c260::/28ff02:c26f:ffff:ffff:ffff:ffff:ffff:ffff
40ff02:c270::/28ff02:c27f:ffff:ffff:ffff:ffff:ffff:ffff
41ff02:c280::/28ff02:c28f:ffff:ffff:ffff:ffff:ffff:ffff
42ff02:c290::/28ff02:c29f:ffff:ffff:ffff:ffff:ffff:ffff
43ff02:c2a0::/28ff02:c2af:ffff:ffff:ffff:ffff:ffff:ffff
44ff02:c2b0::/28ff02:c2bf:ffff:ffff:ffff:ffff:ffff:ffff
45ff02:c2c0::/28ff02:c2cf:ffff:ffff:ffff:ffff:ffff:ffff
46ff02:c2d0::/28ff02:c2df:ffff:ffff:ffff:ffff:ffff:ffff
47ff02:c2e0::/28ff02:c2ef:ffff:ffff:ffff:ffff:ffff:ffff
48ff02:c2f0::/28ff02:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
49ff02:c300::/28ff02:c30f:ffff:ffff:ffff:ffff:ffff:ffff
50ff02:c310::/28ff02:c31f:ffff:ffff:ffff:ffff:ffff:ffff
51ff02:c320::/28ff02:c32f:ffff:ffff:ffff:ffff:ffff:ffff
52ff02:c330::/28ff02:c33f:ffff:ffff:ffff:ffff:ffff:ffff
53ff02:c340::/28ff02:c34f:ffff:ffff:ffff:ffff:ffff:ffff
54ff02:c350::/28ff02:c35f:ffff:ffff:ffff:ffff:ffff:ffff
55ff02:c360::/28ff02:c36f:ffff:ffff:ffff:ffff:ffff:ffff
56ff02:c370::/28ff02:c37f:ffff:ffff:ffff:ffff:ffff:ffff
57ff02:c380::/28ff02:c38f:ffff:ffff:ffff:ffff:ffff:ffff
58ff02:c390::/28ff02:c39f:ffff:ffff:ffff:ffff:ffff:ffff
59ff02:c3a0::/28ff02:c3af:ffff:ffff:ffff:ffff:ffff:ffff
60ff02:c3b0::/28ff02:c3bf:ffff:ffff:ffff:ffff:ffff:ffff
61ff02:c3c0::/28ff02:c3cf:ffff:ffff:ffff:ffff:ffff:ffff
62ff02:c3d0::/28ff02:c3df:ffff:ffff:ffff:ffff:ffff:ffff
63ff02:c3e0::/28ff02:c3ef:ffff:ffff:ffff:ffff:ffff:ffff
64ff02:c3f0::/28ff02:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
65ff02:c400::/28ff02:c40f:ffff:ffff:ffff:ffff:ffff:ffff
66ff02:c410::/28ff02:c41f:ffff:ffff:ffff:ffff:ffff:ffff
67ff02:c420::/28ff02:c42f:ffff:ffff:ffff:ffff:ffff:ffff
68ff02:c430::/28ff02:c43f:ffff:ffff:ffff:ffff:ffff:ffff
69ff02:c440::/28ff02:c44f:ffff:ffff:ffff:ffff:ffff:ffff
70ff02:c450::/28ff02:c45f:ffff:ffff:ffff:ffff:ffff:ffff
71ff02:c460::/28ff02:c46f:ffff:ffff:ffff:ffff:ffff:ffff
72ff02:c470::/28ff02:c47f:ffff:ffff:ffff:ffff:ffff:ffff
73ff02:c480::/28ff02:c48f:ffff:ffff:ffff:ffff:ffff:ffff
74ff02:c490::/28ff02:c49f:ffff:ffff:ffff:ffff:ffff:ffff
75ff02:c4a0::/28ff02:c4af:ffff:ffff:ffff:ffff:ffff:ffff
76ff02:c4b0::/28ff02:c4bf:ffff:ffff:ffff:ffff:ffff:ffff
77ff02:c4c0::/28ff02:c4cf:ffff:ffff:ffff:ffff:ffff:ffff
78ff02:c4d0::/28ff02:c4df:ffff:ffff:ffff:ffff:ffff:ffff
79ff02:c4e0::/28ff02:c4ef:ffff:ffff:ffff:ffff:ffff:ffff
80ff02:c4f0::/28ff02:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
81ff02:c500::/28ff02:c50f:ffff:ffff:ffff:ffff:ffff:ffff
82ff02:c510::/28ff02:c51f:ffff:ffff:ffff:ffff:ffff:ffff
83ff02:c520::/28ff02:c52f:ffff:ffff:ffff:ffff:ffff:ffff
84ff02:c530::/28ff02:c53f:ffff:ffff:ffff:ffff:ffff:ffff
85ff02:c540::/28ff02:c54f:ffff:ffff:ffff:ffff:ffff:ffff
86ff02:c550::/28ff02:c55f:ffff:ffff:ffff:ffff:ffff:ffff
87ff02:c560::/28ff02:c56f:ffff:ffff:ffff:ffff:ffff:ffff
88ff02:c570::/28ff02:c57f:ffff:ffff:ffff:ffff:ffff:ffff
89ff02:c580::/28ff02:c58f:ffff:ffff:ffff:ffff:ffff:ffff
90ff02:c590::/28ff02:c59f:ffff:ffff:ffff:ffff:ffff:ffff
91ff02:c5a0::/28ff02:c5af:ffff:ffff:ffff:ffff:ffff:ffff
92ff02:c5b0::/28ff02:c5bf:ffff:ffff:ffff:ffff:ffff:ffff
93ff02:c5c0::/28ff02:c5cf:ffff:ffff:ffff:ffff:ffff:ffff
94ff02:c5d0::/28ff02:c5df:ffff:ffff:ffff:ffff:ffff:ffff
95ff02:c5e0::/28ff02:c5ef:ffff:ffff:ffff:ffff:ffff:ffff
96ff02:c5f0::/28ff02:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
97ff02:c600::/28ff02:c60f:ffff:ffff:ffff:ffff:ffff:ffff
98ff02:c610::/28ff02:c61f:ffff:ffff:ffff:ffff:ffff:ffff
99ff02:c620::/28ff02:c62f:ffff:ffff:ffff:ffff:ffff:ffff
100ff02:c630::/28ff02:c63f:ffff:ffff:ffff:ffff:ffff:ffff
101ff02:c640::/28ff02:c64f:ffff:ffff:ffff:ffff:ffff:ffff
102ff02:c650::/28ff02:c65f:ffff:ffff:ffff:ffff:ffff:ffff
103ff02:c660::/28ff02:c66f:ffff:ffff:ffff:ffff:ffff:ffff
104ff02:c670::/28ff02:c67f:ffff:ffff:ffff:ffff:ffff:ffff
105ff02:c680::/28ff02:c68f:ffff:ffff:ffff:ffff:ffff:ffff
106ff02:c690::/28ff02:c69f:ffff:ffff:ffff:ffff:ffff:ffff
107ff02:c6a0::/28ff02:c6af:ffff:ffff:ffff:ffff:ffff:ffff
108ff02:c6b0::/28ff02:c6bf:ffff:ffff:ffff:ffff:ffff:ffff
109ff02:c6c0::/28ff02:c6cf:ffff:ffff:ffff:ffff:ffff:ffff
110ff02:c6d0::/28ff02:c6df:ffff:ffff:ffff:ffff:ffff:ffff
111ff02:c6e0::/28ff02:c6ef:ffff:ffff:ffff:ffff:ffff:ffff
112ff02:c6f0::/28ff02:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
113ff02:c700::/28ff02:c70f:ffff:ffff:ffff:ffff:ffff:ffff
114ff02:c710::/28ff02:c71f:ffff:ffff:ffff:ffff:ffff:ffff
115ff02:c720::/28ff02:c72f:ffff:ffff:ffff:ffff:ffff:ffff
116ff02:c730::/28ff02:c73f:ffff:ffff:ffff:ffff:ffff:ffff
117ff02:c740::/28ff02:c74f:ffff:ffff:ffff:ffff:ffff:ffff
118ff02:c750::/28ff02:c75f:ffff:ffff:ffff:ffff:ffff:ffff
119ff02:c760::/28ff02:c76f:ffff:ffff:ffff:ffff:ffff:ffff
120ff02:c770::/28ff02:c77f:ffff:ffff:ffff:ffff:ffff:ffff
121ff02:c780::/28ff02:c78f:ffff:ffff:ffff:ffff:ffff:ffff
122ff02:c790::/28ff02:c79f:ffff:ffff:ffff:ffff:ffff:ffff
123ff02:c7a0::/28ff02:c7af:ffff:ffff:ffff:ffff:ffff:ffff
124ff02:c7b0::/28ff02:c7bf:ffff:ffff:ffff:ffff:ffff:ffff
125ff02:c7c0::/28ff02:c7cf:ffff:ffff:ffff:ffff:ffff:ffff
126ff02:c7d0::/28ff02:c7df:ffff:ffff:ffff:ffff:ffff:ffff
127ff02:c7e0::/28ff02:c7ef:ffff:ffff:ffff:ffff:ffff:ffff
128ff02:c7f0::/28ff02:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
129ff02:c800::/28ff02:c80f:ffff:ffff:ffff:ffff:ffff:ffff
130ff02:c810::/28ff02:c81f:ffff:ffff:ffff:ffff:ffff:ffff
131ff02:c820::/28ff02:c82f:ffff:ffff:ffff:ffff:ffff:ffff
132ff02:c830::/28ff02:c83f:ffff:ffff:ffff:ffff:ffff:ffff
133ff02:c840::/28ff02:c84f:ffff:ffff:ffff:ffff:ffff:ffff
134ff02:c850::/28ff02:c85f:ffff:ffff:ffff:ffff:ffff:ffff
135ff02:c860::/28ff02:c86f:ffff:ffff:ffff:ffff:ffff:ffff
136ff02:c870::/28ff02:c87f:ffff:ffff:ffff:ffff:ffff:ffff
137ff02:c880::/28ff02:c88f:ffff:ffff:ffff:ffff:ffff:ffff
138ff02:c890::/28ff02:c89f:ffff:ffff:ffff:ffff:ffff:ffff
139ff02:c8a0::/28ff02:c8af:ffff:ffff:ffff:ffff:ffff:ffff
140ff02:c8b0::/28ff02:c8bf:ffff:ffff:ffff:ffff:ffff:ffff
141ff02:c8c0::/28ff02:c8cf:ffff:ffff:ffff:ffff:ffff:ffff
142ff02:c8d0::/28ff02:c8df:ffff:ffff:ffff:ffff:ffff:ffff
143ff02:c8e0::/28ff02:c8ef:ffff:ffff:ffff:ffff:ffff:ffff
144ff02:c8f0::/28ff02:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
145ff02:c900::/28ff02:c90f:ffff:ffff:ffff:ffff:ffff:ffff
146ff02:c910::/28ff02:c91f:ffff:ffff:ffff:ffff:ffff:ffff
147ff02:c920::/28ff02:c92f:ffff:ffff:ffff:ffff:ffff:ffff
148ff02:c930::/28ff02:c93f:ffff:ffff:ffff:ffff:ffff:ffff
149ff02:c940::/28ff02:c94f:ffff:ffff:ffff:ffff:ffff:ffff
150ff02:c950::/28ff02:c95f:ffff:ffff:ffff:ffff:ffff:ffff
151ff02:c960::/28ff02:c96f:ffff:ffff:ffff:ffff:ffff:ffff
152ff02:c970::/28ff02:c97f:ffff:ffff:ffff:ffff:ffff:ffff
153ff02:c980::/28ff02:c98f:ffff:ffff:ffff:ffff:ffff:ffff
154ff02:c990::/28ff02:c99f:ffff:ffff:ffff:ffff:ffff:ffff
155ff02:c9a0::/28ff02:c9af:ffff:ffff:ffff:ffff:ffff:ffff
156ff02:c9b0::/28ff02:c9bf:ffff:ffff:ffff:ffff:ffff:ffff
157ff02:c9c0::/28ff02:c9cf:ffff:ffff:ffff:ffff:ffff:ffff
158ff02:c9d0::/28ff02:c9df:ffff:ffff:ffff:ffff:ffff:ffff
159ff02:c9e0::/28ff02:c9ef:ffff:ffff:ffff:ffff:ffff:ffff
160ff02:c9f0::/28ff02:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
161ff02:ca00::/28ff02:ca0f:ffff:ffff:ffff:ffff:ffff:ffff
162ff02:ca10::/28ff02:ca1f:ffff:ffff:ffff:ffff:ffff:ffff
163ff02:ca20::/28ff02:ca2f:ffff:ffff:ffff:ffff:ffff:ffff
164ff02:ca30::/28ff02:ca3f:ffff:ffff:ffff:ffff:ffff:ffff
165ff02:ca40::/28ff02:ca4f:ffff:ffff:ffff:ffff:ffff:ffff
166ff02:ca50::/28ff02:ca5f:ffff:ffff:ffff:ffff:ffff:ffff
167ff02:ca60::/28ff02:ca6f:ffff:ffff:ffff:ffff:ffff:ffff
168ff02:ca70::/28ff02:ca7f:ffff:ffff:ffff:ffff:ffff:ffff
169ff02:ca80::/28ff02:ca8f:ffff:ffff:ffff:ffff:ffff:ffff
170ff02:ca90::/28ff02:ca9f:ffff:ffff:ffff:ffff:ffff:ffff
171ff02:caa0::/28ff02:caaf:ffff:ffff:ffff:ffff:ffff:ffff
172ff02:cab0::/28ff02:cabf:ffff:ffff:ffff:ffff:ffff:ffff
173ff02:cac0::/28ff02:cacf:ffff:ffff:ffff:ffff:ffff:ffff
174ff02:cad0::/28ff02:cadf:ffff:ffff:ffff:ffff:ffff:ffff
175ff02:cae0::/28ff02:caef:ffff:ffff:ffff:ffff:ffff:ffff
176ff02:caf0::/28ff02:caff:ffff:ffff:ffff:ffff:ffff:ffff
177ff02:cb00::/28ff02:cb0f:ffff:ffff:ffff:ffff:ffff:ffff
178ff02:cb10::/28ff02:cb1f:ffff:ffff:ffff:ffff:ffff:ffff
179ff02:cb20::/28ff02:cb2f:ffff:ffff:ffff:ffff:ffff:ffff
180ff02:cb30::/28ff02:cb3f:ffff:ffff:ffff:ffff:ffff:ffff
181ff02:cb40::/28ff02:cb4f:ffff:ffff:ffff:ffff:ffff:ffff
182ff02:cb50::/28ff02:cb5f:ffff:ffff:ffff:ffff:ffff:ffff
183ff02:cb60::/28ff02:cb6f:ffff:ffff:ffff:ffff:ffff:ffff
184ff02:cb70::/28ff02:cb7f:ffff:ffff:ffff:ffff:ffff:ffff
185ff02:cb80::/28ff02:cb8f:ffff:ffff:ffff:ffff:ffff:ffff
186ff02:cb90::/28ff02:cb9f:ffff:ffff:ffff:ffff:ffff:ffff
187ff02:cba0::/28ff02:cbaf:ffff:ffff:ffff:ffff:ffff:ffff
188ff02:cbb0::/28ff02:cbbf:ffff:ffff:ffff:ffff:ffff:ffff
189ff02:cbc0::/28ff02:cbcf:ffff:ffff:ffff:ffff:ffff:ffff
190ff02:cbd0::/28ff02:cbdf:ffff:ffff:ffff:ffff:ffff:ffff
191ff02:cbe0::/28ff02:cbef:ffff:ffff:ffff:ffff:ffff:ffff
192ff02:cbf0::/28ff02:cbff:ffff:ffff:ffff:ffff:ffff:ffff
193ff02:cc00::/28ff02:cc0f:ffff:ffff:ffff:ffff:ffff:ffff
194ff02:cc10::/28ff02:cc1f:ffff:ffff:ffff:ffff:ffff:ffff
195ff02:cc20::/28ff02:cc2f:ffff:ffff:ffff:ffff:ffff:ffff
196ff02:cc30::/28ff02:cc3f:ffff:ffff:ffff:ffff:ffff:ffff
197ff02:cc40::/28ff02:cc4f:ffff:ffff:ffff:ffff:ffff:ffff
198ff02:cc50::/28ff02:cc5f:ffff:ffff:ffff:ffff:ffff:ffff
199ff02:cc60::/28ff02:cc6f:ffff:ffff:ffff:ffff:ffff:ffff
200ff02:cc70::/28ff02:cc7f:ffff:ffff:ffff:ffff:ffff:ffff
201ff02:cc80::/28ff02:cc8f:ffff:ffff:ffff:ffff:ffff:ffff
202ff02:cc90::/28ff02:cc9f:ffff:ffff:ffff:ffff:ffff:ffff
203ff02:cca0::/28ff02:ccaf:ffff:ffff:ffff:ffff:ffff:ffff
204ff02:ccb0::/28ff02:ccbf:ffff:ffff:ffff:ffff:ffff:ffff
205ff02:ccc0::/28ff02:cccf:ffff:ffff:ffff:ffff:ffff:ffff
206ff02:ccd0::/28ff02:ccdf:ffff:ffff:ffff:ffff:ffff:ffff
207ff02:cce0::/28ff02:ccef:ffff:ffff:ffff:ffff:ffff:ffff
208ff02:ccf0::/28ff02:ccff:ffff:ffff:ffff:ffff:ffff:ffff
209ff02:cd00::/28ff02:cd0f:ffff:ffff:ffff:ffff:ffff:ffff
210ff02:cd10::/28ff02:cd1f:ffff:ffff:ffff:ffff:ffff:ffff
211ff02:cd20::/28ff02:cd2f:ffff:ffff:ffff:ffff:ffff:ffff
212ff02:cd30::/28ff02:cd3f:ffff:ffff:ffff:ffff:ffff:ffff
213ff02:cd40::/28ff02:cd4f:ffff:ffff:ffff:ffff:ffff:ffff
214ff02:cd50::/28ff02:cd5f:ffff:ffff:ffff:ffff:ffff:ffff
215ff02:cd60::/28ff02:cd6f:ffff:ffff:ffff:ffff:ffff:ffff
216ff02:cd70::/28ff02:cd7f:ffff:ffff:ffff:ffff:ffff:ffff
217ff02:cd80::/28ff02:cd8f:ffff:ffff:ffff:ffff:ffff:ffff
218ff02:cd90::/28ff02:cd9f:ffff:ffff:ffff:ffff:ffff:ffff
219ff02:cda0::/28ff02:cdaf:ffff:ffff:ffff:ffff:ffff:ffff
220ff02:cdb0::/28ff02:cdbf:ffff:ffff:ffff:ffff:ffff:ffff
221ff02:cdc0::/28ff02:cdcf:ffff:ffff:ffff:ffff:ffff:ffff
222ff02:cdd0::/28ff02:cddf:ffff:ffff:ffff:ffff:ffff:ffff
223ff02:cde0::/28ff02:cdef:ffff:ffff:ffff:ffff:ffff:ffff
224ff02:cdf0::/28ff02:cdff:ffff:ffff:ffff:ffff:ffff:ffff
225ff02:ce00::/28ff02:ce0f:ffff:ffff:ffff:ffff:ffff:ffff
226ff02:ce10::/28ff02:ce1f:ffff:ffff:ffff:ffff:ffff:ffff
227ff02:ce20::/28ff02:ce2f:ffff:ffff:ffff:ffff:ffff:ffff
228ff02:ce30::/28ff02:ce3f:ffff:ffff:ffff:ffff:ffff:ffff
229ff02:ce40::/28ff02:ce4f:ffff:ffff:ffff:ffff:ffff:ffff
230ff02:ce50::/28ff02:ce5f:ffff:ffff:ffff:ffff:ffff:ffff
231ff02:ce60::/28ff02:ce6f:ffff:ffff:ffff:ffff:ffff:ffff
232ff02:ce70::/28ff02:ce7f:ffff:ffff:ffff:ffff:ffff:ffff
233ff02:ce80::/28ff02:ce8f:ffff:ffff:ffff:ffff:ffff:ffff
234ff02:ce90::/28ff02:ce9f:ffff:ffff:ffff:ffff:ffff:ffff
235ff02:cea0::/28ff02:ceaf:ffff:ffff:ffff:ffff:ffff:ffff
236ff02:ceb0::/28ff02:cebf:ffff:ffff:ffff:ffff:ffff:ffff
237ff02:cec0::/28ff02:cecf:ffff:ffff:ffff:ffff:ffff:ffff
238ff02:ced0::/28ff02:cedf:ffff:ffff:ffff:ffff:ffff:ffff
239ff02:cee0::/28ff02:ceef:ffff:ffff:ffff:ffff:ffff:ffff
240ff02:cef0::/28ff02:ceff:ffff:ffff:ffff:ffff:ffff:ffff
241ff02:cf00::/28ff02:cf0f:ffff:ffff:ffff:ffff:ffff:ffff
242ff02:cf10::/28ff02:cf1f:ffff:ffff:ffff:ffff:ffff:ffff
243ff02:cf20::/28ff02:cf2f:ffff:ffff:ffff:ffff:ffff:ffff
244ff02:cf30::/28ff02:cf3f:ffff:ffff:ffff:ffff:ffff:ffff
245ff02:cf40::/28ff02:cf4f:ffff:ffff:ffff:ffff:ffff:ffff
246ff02:cf50::/28ff02:cf5f:ffff:ffff:ffff:ffff:ffff:ffff
247ff02:cf60::/28ff02:cf6f:ffff:ffff:ffff:ffff:ffff:ffff
248ff02:cf70::/28ff02:cf7f:ffff:ffff:ffff:ffff:ffff:ffff
249ff02:cf80::/28ff02:cf8f:ffff:ffff:ffff:ffff:ffff:ffff
250ff02:cf90::/28ff02:cf9f:ffff:ffff:ffff:ffff:ffff:ffff
251ff02:cfa0::/28ff02:cfaf:ffff:ffff:ffff:ffff:ffff:ffff
252ff02:cfb0::/28ff02:cfbf:ffff:ffff:ffff:ffff:ffff:ffff
253ff02:cfc0::/28ff02:cfcf:ffff:ffff:ffff:ffff:ffff:ffff
254ff02:cfd0::/28ff02:cfdf:ffff:ffff:ffff:ffff:ffff:ffff
255ff02:cfe0::/28ff02:cfef:ffff:ffff:ffff:ffff:ffff:ffff
256ff02:cff0::/28ff02:cfff: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.