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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
fe82:c000::/20
First address
fe82:c000::
Last address
fe82: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
fe82:c000:0000:0000:0000:0000:0000:0000
Type
Link-local fe80::/10
Every IPv6 interface has one; not routed
Reverse DNS zone
c.2.8.e.f.ip6.arpa
Split into smaller subnets/28
/21 (2)/22 (4)/23 (8)/24 (16)/28 (256)/32 (4,096)/36 (65,536)

fe82:c000::/20 makes 256 subnets of /28.

Subnets
#SubnetLast address
1fe82:c000::/28fe82:c00f:ffff:ffff:ffff:ffff:ffff:ffff
2fe82:c010::/28fe82:c01f:ffff:ffff:ffff:ffff:ffff:ffff
3fe82:c020::/28fe82:c02f:ffff:ffff:ffff:ffff:ffff:ffff
4fe82:c030::/28fe82:c03f:ffff:ffff:ffff:ffff:ffff:ffff
5fe82:c040::/28fe82:c04f:ffff:ffff:ffff:ffff:ffff:ffff
6fe82:c050::/28fe82:c05f:ffff:ffff:ffff:ffff:ffff:ffff
7fe82:c060::/28fe82:c06f:ffff:ffff:ffff:ffff:ffff:ffff
8fe82:c070::/28fe82:c07f:ffff:ffff:ffff:ffff:ffff:ffff
9fe82:c080::/28fe82:c08f:ffff:ffff:ffff:ffff:ffff:ffff
10fe82:c090::/28fe82:c09f:ffff:ffff:ffff:ffff:ffff:ffff
11fe82:c0a0::/28fe82:c0af:ffff:ffff:ffff:ffff:ffff:ffff
12fe82:c0b0::/28fe82:c0bf:ffff:ffff:ffff:ffff:ffff:ffff
13fe82:c0c0::/28fe82:c0cf:ffff:ffff:ffff:ffff:ffff:ffff
14fe82:c0d0::/28fe82:c0df:ffff:ffff:ffff:ffff:ffff:ffff
15fe82:c0e0::/28fe82:c0ef:ffff:ffff:ffff:ffff:ffff:ffff
16fe82:c0f0::/28fe82:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
17fe82:c100::/28fe82:c10f:ffff:ffff:ffff:ffff:ffff:ffff
18fe82:c110::/28fe82:c11f:ffff:ffff:ffff:ffff:ffff:ffff
19fe82:c120::/28fe82:c12f:ffff:ffff:ffff:ffff:ffff:ffff
20fe82:c130::/28fe82:c13f:ffff:ffff:ffff:ffff:ffff:ffff
21fe82:c140::/28fe82:c14f:ffff:ffff:ffff:ffff:ffff:ffff
22fe82:c150::/28fe82:c15f:ffff:ffff:ffff:ffff:ffff:ffff
23fe82:c160::/28fe82:c16f:ffff:ffff:ffff:ffff:ffff:ffff
24fe82:c170::/28fe82:c17f:ffff:ffff:ffff:ffff:ffff:ffff
25fe82:c180::/28fe82:c18f:ffff:ffff:ffff:ffff:ffff:ffff
26fe82:c190::/28fe82:c19f:ffff:ffff:ffff:ffff:ffff:ffff
27fe82:c1a0::/28fe82:c1af:ffff:ffff:ffff:ffff:ffff:ffff
28fe82:c1b0::/28fe82:c1bf:ffff:ffff:ffff:ffff:ffff:ffff
29fe82:c1c0::/28fe82:c1cf:ffff:ffff:ffff:ffff:ffff:ffff
30fe82:c1d0::/28fe82:c1df:ffff:ffff:ffff:ffff:ffff:ffff
31fe82:c1e0::/28fe82:c1ef:ffff:ffff:ffff:ffff:ffff:ffff
32fe82:c1f0::/28fe82:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
33fe82:c200::/28fe82:c20f:ffff:ffff:ffff:ffff:ffff:ffff
34fe82:c210::/28fe82:c21f:ffff:ffff:ffff:ffff:ffff:ffff
35fe82:c220::/28fe82:c22f:ffff:ffff:ffff:ffff:ffff:ffff
36fe82:c230::/28fe82:c23f:ffff:ffff:ffff:ffff:ffff:ffff
37fe82:c240::/28fe82:c24f:ffff:ffff:ffff:ffff:ffff:ffff
38fe82:c250::/28fe82:c25f:ffff:ffff:ffff:ffff:ffff:ffff
39fe82:c260::/28fe82:c26f:ffff:ffff:ffff:ffff:ffff:ffff
40fe82:c270::/28fe82:c27f:ffff:ffff:ffff:ffff:ffff:ffff
41fe82:c280::/28fe82:c28f:ffff:ffff:ffff:ffff:ffff:ffff
42fe82:c290::/28fe82:c29f:ffff:ffff:ffff:ffff:ffff:ffff
43fe82:c2a0::/28fe82:c2af:ffff:ffff:ffff:ffff:ffff:ffff
44fe82:c2b0::/28fe82:c2bf:ffff:ffff:ffff:ffff:ffff:ffff
45fe82:c2c0::/28fe82:c2cf:ffff:ffff:ffff:ffff:ffff:ffff
46fe82:c2d0::/28fe82:c2df:ffff:ffff:ffff:ffff:ffff:ffff
47fe82:c2e0::/28fe82:c2ef:ffff:ffff:ffff:ffff:ffff:ffff
48fe82:c2f0::/28fe82:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
49fe82:c300::/28fe82:c30f:ffff:ffff:ffff:ffff:ffff:ffff
50fe82:c310::/28fe82:c31f:ffff:ffff:ffff:ffff:ffff:ffff
51fe82:c320::/28fe82:c32f:ffff:ffff:ffff:ffff:ffff:ffff
52fe82:c330::/28fe82:c33f:ffff:ffff:ffff:ffff:ffff:ffff
53fe82:c340::/28fe82:c34f:ffff:ffff:ffff:ffff:ffff:ffff
54fe82:c350::/28fe82:c35f:ffff:ffff:ffff:ffff:ffff:ffff
55fe82:c360::/28fe82:c36f:ffff:ffff:ffff:ffff:ffff:ffff
56fe82:c370::/28fe82:c37f:ffff:ffff:ffff:ffff:ffff:ffff
57fe82:c380::/28fe82:c38f:ffff:ffff:ffff:ffff:ffff:ffff
58fe82:c390::/28fe82:c39f:ffff:ffff:ffff:ffff:ffff:ffff
59fe82:c3a0::/28fe82:c3af:ffff:ffff:ffff:ffff:ffff:ffff
60fe82:c3b0::/28fe82:c3bf:ffff:ffff:ffff:ffff:ffff:ffff
61fe82:c3c0::/28fe82:c3cf:ffff:ffff:ffff:ffff:ffff:ffff
62fe82:c3d0::/28fe82:c3df:ffff:ffff:ffff:ffff:ffff:ffff
63fe82:c3e0::/28fe82:c3ef:ffff:ffff:ffff:ffff:ffff:ffff
64fe82:c3f0::/28fe82:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
65fe82:c400::/28fe82:c40f:ffff:ffff:ffff:ffff:ffff:ffff
66fe82:c410::/28fe82:c41f:ffff:ffff:ffff:ffff:ffff:ffff
67fe82:c420::/28fe82:c42f:ffff:ffff:ffff:ffff:ffff:ffff
68fe82:c430::/28fe82:c43f:ffff:ffff:ffff:ffff:ffff:ffff
69fe82:c440::/28fe82:c44f:ffff:ffff:ffff:ffff:ffff:ffff
70fe82:c450::/28fe82:c45f:ffff:ffff:ffff:ffff:ffff:ffff
71fe82:c460::/28fe82:c46f:ffff:ffff:ffff:ffff:ffff:ffff
72fe82:c470::/28fe82:c47f:ffff:ffff:ffff:ffff:ffff:ffff
73fe82:c480::/28fe82:c48f:ffff:ffff:ffff:ffff:ffff:ffff
74fe82:c490::/28fe82:c49f:ffff:ffff:ffff:ffff:ffff:ffff
75fe82:c4a0::/28fe82:c4af:ffff:ffff:ffff:ffff:ffff:ffff
76fe82:c4b0::/28fe82:c4bf:ffff:ffff:ffff:ffff:ffff:ffff
77fe82:c4c0::/28fe82:c4cf:ffff:ffff:ffff:ffff:ffff:ffff
78fe82:c4d0::/28fe82:c4df:ffff:ffff:ffff:ffff:ffff:ffff
79fe82:c4e0::/28fe82:c4ef:ffff:ffff:ffff:ffff:ffff:ffff
80fe82:c4f0::/28fe82:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
81fe82:c500::/28fe82:c50f:ffff:ffff:ffff:ffff:ffff:ffff
82fe82:c510::/28fe82:c51f:ffff:ffff:ffff:ffff:ffff:ffff
83fe82:c520::/28fe82:c52f:ffff:ffff:ffff:ffff:ffff:ffff
84fe82:c530::/28fe82:c53f:ffff:ffff:ffff:ffff:ffff:ffff
85fe82:c540::/28fe82:c54f:ffff:ffff:ffff:ffff:ffff:ffff
86fe82:c550::/28fe82:c55f:ffff:ffff:ffff:ffff:ffff:ffff
87fe82:c560::/28fe82:c56f:ffff:ffff:ffff:ffff:ffff:ffff
88fe82:c570::/28fe82:c57f:ffff:ffff:ffff:ffff:ffff:ffff
89fe82:c580::/28fe82:c58f:ffff:ffff:ffff:ffff:ffff:ffff
90fe82:c590::/28fe82:c59f:ffff:ffff:ffff:ffff:ffff:ffff
91fe82:c5a0::/28fe82:c5af:ffff:ffff:ffff:ffff:ffff:ffff
92fe82:c5b0::/28fe82:c5bf:ffff:ffff:ffff:ffff:ffff:ffff
93fe82:c5c0::/28fe82:c5cf:ffff:ffff:ffff:ffff:ffff:ffff
94fe82:c5d0::/28fe82:c5df:ffff:ffff:ffff:ffff:ffff:ffff
95fe82:c5e0::/28fe82:c5ef:ffff:ffff:ffff:ffff:ffff:ffff
96fe82:c5f0::/28fe82:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
97fe82:c600::/28fe82:c60f:ffff:ffff:ffff:ffff:ffff:ffff
98fe82:c610::/28fe82:c61f:ffff:ffff:ffff:ffff:ffff:ffff
99fe82:c620::/28fe82:c62f:ffff:ffff:ffff:ffff:ffff:ffff
100fe82:c630::/28fe82:c63f:ffff:ffff:ffff:ffff:ffff:ffff
101fe82:c640::/28fe82:c64f:ffff:ffff:ffff:ffff:ffff:ffff
102fe82:c650::/28fe82:c65f:ffff:ffff:ffff:ffff:ffff:ffff
103fe82:c660::/28fe82:c66f:ffff:ffff:ffff:ffff:ffff:ffff
104fe82:c670::/28fe82:c67f:ffff:ffff:ffff:ffff:ffff:ffff
105fe82:c680::/28fe82:c68f:ffff:ffff:ffff:ffff:ffff:ffff
106fe82:c690::/28fe82:c69f:ffff:ffff:ffff:ffff:ffff:ffff
107fe82:c6a0::/28fe82:c6af:ffff:ffff:ffff:ffff:ffff:ffff
108fe82:c6b0::/28fe82:c6bf:ffff:ffff:ffff:ffff:ffff:ffff
109fe82:c6c0::/28fe82:c6cf:ffff:ffff:ffff:ffff:ffff:ffff
110fe82:c6d0::/28fe82:c6df:ffff:ffff:ffff:ffff:ffff:ffff
111fe82:c6e0::/28fe82:c6ef:ffff:ffff:ffff:ffff:ffff:ffff
112fe82:c6f0::/28fe82:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
113fe82:c700::/28fe82:c70f:ffff:ffff:ffff:ffff:ffff:ffff
114fe82:c710::/28fe82:c71f:ffff:ffff:ffff:ffff:ffff:ffff
115fe82:c720::/28fe82:c72f:ffff:ffff:ffff:ffff:ffff:ffff
116fe82:c730::/28fe82:c73f:ffff:ffff:ffff:ffff:ffff:ffff
117fe82:c740::/28fe82:c74f:ffff:ffff:ffff:ffff:ffff:ffff
118fe82:c750::/28fe82:c75f:ffff:ffff:ffff:ffff:ffff:ffff
119fe82:c760::/28fe82:c76f:ffff:ffff:ffff:ffff:ffff:ffff
120fe82:c770::/28fe82:c77f:ffff:ffff:ffff:ffff:ffff:ffff
121fe82:c780::/28fe82:c78f:ffff:ffff:ffff:ffff:ffff:ffff
122fe82:c790::/28fe82:c79f:ffff:ffff:ffff:ffff:ffff:ffff
123fe82:c7a0::/28fe82:c7af:ffff:ffff:ffff:ffff:ffff:ffff
124fe82:c7b0::/28fe82:c7bf:ffff:ffff:ffff:ffff:ffff:ffff
125fe82:c7c0::/28fe82:c7cf:ffff:ffff:ffff:ffff:ffff:ffff
126fe82:c7d0::/28fe82:c7df:ffff:ffff:ffff:ffff:ffff:ffff
127fe82:c7e0::/28fe82:c7ef:ffff:ffff:ffff:ffff:ffff:ffff
128fe82:c7f0::/28fe82:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
129fe82:c800::/28fe82:c80f:ffff:ffff:ffff:ffff:ffff:ffff
130fe82:c810::/28fe82:c81f:ffff:ffff:ffff:ffff:ffff:ffff
131fe82:c820::/28fe82:c82f:ffff:ffff:ffff:ffff:ffff:ffff
132fe82:c830::/28fe82:c83f:ffff:ffff:ffff:ffff:ffff:ffff
133fe82:c840::/28fe82:c84f:ffff:ffff:ffff:ffff:ffff:ffff
134fe82:c850::/28fe82:c85f:ffff:ffff:ffff:ffff:ffff:ffff
135fe82:c860::/28fe82:c86f:ffff:ffff:ffff:ffff:ffff:ffff
136fe82:c870::/28fe82:c87f:ffff:ffff:ffff:ffff:ffff:ffff
137fe82:c880::/28fe82:c88f:ffff:ffff:ffff:ffff:ffff:ffff
138fe82:c890::/28fe82:c89f:ffff:ffff:ffff:ffff:ffff:ffff
139fe82:c8a0::/28fe82:c8af:ffff:ffff:ffff:ffff:ffff:ffff
140fe82:c8b0::/28fe82:c8bf:ffff:ffff:ffff:ffff:ffff:ffff
141fe82:c8c0::/28fe82:c8cf:ffff:ffff:ffff:ffff:ffff:ffff
142fe82:c8d0::/28fe82:c8df:ffff:ffff:ffff:ffff:ffff:ffff
143fe82:c8e0::/28fe82:c8ef:ffff:ffff:ffff:ffff:ffff:ffff
144fe82:c8f0::/28fe82:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
145fe82:c900::/28fe82:c90f:ffff:ffff:ffff:ffff:ffff:ffff
146fe82:c910::/28fe82:c91f:ffff:ffff:ffff:ffff:ffff:ffff
147fe82:c920::/28fe82:c92f:ffff:ffff:ffff:ffff:ffff:ffff
148fe82:c930::/28fe82:c93f:ffff:ffff:ffff:ffff:ffff:ffff
149fe82:c940::/28fe82:c94f:ffff:ffff:ffff:ffff:ffff:ffff
150fe82:c950::/28fe82:c95f:ffff:ffff:ffff:ffff:ffff:ffff
151fe82:c960::/28fe82:c96f:ffff:ffff:ffff:ffff:ffff:ffff
152fe82:c970::/28fe82:c97f:ffff:ffff:ffff:ffff:ffff:ffff
153fe82:c980::/28fe82:c98f:ffff:ffff:ffff:ffff:ffff:ffff
154fe82:c990::/28fe82:c99f:ffff:ffff:ffff:ffff:ffff:ffff
155fe82:c9a0::/28fe82:c9af:ffff:ffff:ffff:ffff:ffff:ffff
156fe82:c9b0::/28fe82:c9bf:ffff:ffff:ffff:ffff:ffff:ffff
157fe82:c9c0::/28fe82:c9cf:ffff:ffff:ffff:ffff:ffff:ffff
158fe82:c9d0::/28fe82:c9df:ffff:ffff:ffff:ffff:ffff:ffff
159fe82:c9e0::/28fe82:c9ef:ffff:ffff:ffff:ffff:ffff:ffff
160fe82:c9f0::/28fe82:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
161fe82:ca00::/28fe82:ca0f:ffff:ffff:ffff:ffff:ffff:ffff
162fe82:ca10::/28fe82:ca1f:ffff:ffff:ffff:ffff:ffff:ffff
163fe82:ca20::/28fe82:ca2f:ffff:ffff:ffff:ffff:ffff:ffff
164fe82:ca30::/28fe82:ca3f:ffff:ffff:ffff:ffff:ffff:ffff
165fe82:ca40::/28fe82:ca4f:ffff:ffff:ffff:ffff:ffff:ffff
166fe82:ca50::/28fe82:ca5f:ffff:ffff:ffff:ffff:ffff:ffff
167fe82:ca60::/28fe82:ca6f:ffff:ffff:ffff:ffff:ffff:ffff
168fe82:ca70::/28fe82:ca7f:ffff:ffff:ffff:ffff:ffff:ffff
169fe82:ca80::/28fe82:ca8f:ffff:ffff:ffff:ffff:ffff:ffff
170fe82:ca90::/28fe82:ca9f:ffff:ffff:ffff:ffff:ffff:ffff
171fe82:caa0::/28fe82:caaf:ffff:ffff:ffff:ffff:ffff:ffff
172fe82:cab0::/28fe82:cabf:ffff:ffff:ffff:ffff:ffff:ffff
173fe82:cac0::/28fe82:cacf:ffff:ffff:ffff:ffff:ffff:ffff
174fe82:cad0::/28fe82:cadf:ffff:ffff:ffff:ffff:ffff:ffff
175fe82:cae0::/28fe82:caef:ffff:ffff:ffff:ffff:ffff:ffff
176fe82:caf0::/28fe82:caff:ffff:ffff:ffff:ffff:ffff:ffff
177fe82:cb00::/28fe82:cb0f:ffff:ffff:ffff:ffff:ffff:ffff
178fe82:cb10::/28fe82:cb1f:ffff:ffff:ffff:ffff:ffff:ffff
179fe82:cb20::/28fe82:cb2f:ffff:ffff:ffff:ffff:ffff:ffff
180fe82:cb30::/28fe82:cb3f:ffff:ffff:ffff:ffff:ffff:ffff
181fe82:cb40::/28fe82:cb4f:ffff:ffff:ffff:ffff:ffff:ffff
182fe82:cb50::/28fe82:cb5f:ffff:ffff:ffff:ffff:ffff:ffff
183fe82:cb60::/28fe82:cb6f:ffff:ffff:ffff:ffff:ffff:ffff
184fe82:cb70::/28fe82:cb7f:ffff:ffff:ffff:ffff:ffff:ffff
185fe82:cb80::/28fe82:cb8f:ffff:ffff:ffff:ffff:ffff:ffff
186fe82:cb90::/28fe82:cb9f:ffff:ffff:ffff:ffff:ffff:ffff
187fe82:cba0::/28fe82:cbaf:ffff:ffff:ffff:ffff:ffff:ffff
188fe82:cbb0::/28fe82:cbbf:ffff:ffff:ffff:ffff:ffff:ffff
189fe82:cbc0::/28fe82:cbcf:ffff:ffff:ffff:ffff:ffff:ffff
190fe82:cbd0::/28fe82:cbdf:ffff:ffff:ffff:ffff:ffff:ffff
191fe82:cbe0::/28fe82:cbef:ffff:ffff:ffff:ffff:ffff:ffff
192fe82:cbf0::/28fe82:cbff:ffff:ffff:ffff:ffff:ffff:ffff
193fe82:cc00::/28fe82:cc0f:ffff:ffff:ffff:ffff:ffff:ffff
194fe82:cc10::/28fe82:cc1f:ffff:ffff:ffff:ffff:ffff:ffff
195fe82:cc20::/28fe82:cc2f:ffff:ffff:ffff:ffff:ffff:ffff
196fe82:cc30::/28fe82:cc3f:ffff:ffff:ffff:ffff:ffff:ffff
197fe82:cc40::/28fe82:cc4f:ffff:ffff:ffff:ffff:ffff:ffff
198fe82:cc50::/28fe82:cc5f:ffff:ffff:ffff:ffff:ffff:ffff
199fe82:cc60::/28fe82:cc6f:ffff:ffff:ffff:ffff:ffff:ffff
200fe82:cc70::/28fe82:cc7f:ffff:ffff:ffff:ffff:ffff:ffff
201fe82:cc80::/28fe82:cc8f:ffff:ffff:ffff:ffff:ffff:ffff
202fe82:cc90::/28fe82:cc9f:ffff:ffff:ffff:ffff:ffff:ffff
203fe82:cca0::/28fe82:ccaf:ffff:ffff:ffff:ffff:ffff:ffff
204fe82:ccb0::/28fe82:ccbf:ffff:ffff:ffff:ffff:ffff:ffff
205fe82:ccc0::/28fe82:cccf:ffff:ffff:ffff:ffff:ffff:ffff
206fe82:ccd0::/28fe82:ccdf:ffff:ffff:ffff:ffff:ffff:ffff
207fe82:cce0::/28fe82:ccef:ffff:ffff:ffff:ffff:ffff:ffff
208fe82:ccf0::/28fe82:ccff:ffff:ffff:ffff:ffff:ffff:ffff
209fe82:cd00::/28fe82:cd0f:ffff:ffff:ffff:ffff:ffff:ffff
210fe82:cd10::/28fe82:cd1f:ffff:ffff:ffff:ffff:ffff:ffff
211fe82:cd20::/28fe82:cd2f:ffff:ffff:ffff:ffff:ffff:ffff
212fe82:cd30::/28fe82:cd3f:ffff:ffff:ffff:ffff:ffff:ffff
213fe82:cd40::/28fe82:cd4f:ffff:ffff:ffff:ffff:ffff:ffff
214fe82:cd50::/28fe82:cd5f:ffff:ffff:ffff:ffff:ffff:ffff
215fe82:cd60::/28fe82:cd6f:ffff:ffff:ffff:ffff:ffff:ffff
216fe82:cd70::/28fe82:cd7f:ffff:ffff:ffff:ffff:ffff:ffff
217fe82:cd80::/28fe82:cd8f:ffff:ffff:ffff:ffff:ffff:ffff
218fe82:cd90::/28fe82:cd9f:ffff:ffff:ffff:ffff:ffff:ffff
219fe82:cda0::/28fe82:cdaf:ffff:ffff:ffff:ffff:ffff:ffff
220fe82:cdb0::/28fe82:cdbf:ffff:ffff:ffff:ffff:ffff:ffff
221fe82:cdc0::/28fe82:cdcf:ffff:ffff:ffff:ffff:ffff:ffff
222fe82:cdd0::/28fe82:cddf:ffff:ffff:ffff:ffff:ffff:ffff
223fe82:cde0::/28fe82:cdef:ffff:ffff:ffff:ffff:ffff:ffff
224fe82:cdf0::/28fe82:cdff:ffff:ffff:ffff:ffff:ffff:ffff
225fe82:ce00::/28fe82:ce0f:ffff:ffff:ffff:ffff:ffff:ffff
226fe82:ce10::/28fe82:ce1f:ffff:ffff:ffff:ffff:ffff:ffff
227fe82:ce20::/28fe82:ce2f:ffff:ffff:ffff:ffff:ffff:ffff
228fe82:ce30::/28fe82:ce3f:ffff:ffff:ffff:ffff:ffff:ffff
229fe82:ce40::/28fe82:ce4f:ffff:ffff:ffff:ffff:ffff:ffff
230fe82:ce50::/28fe82:ce5f:ffff:ffff:ffff:ffff:ffff:ffff
231fe82:ce60::/28fe82:ce6f:ffff:ffff:ffff:ffff:ffff:ffff
232fe82:ce70::/28fe82:ce7f:ffff:ffff:ffff:ffff:ffff:ffff
233fe82:ce80::/28fe82:ce8f:ffff:ffff:ffff:ffff:ffff:ffff
234fe82:ce90::/28fe82:ce9f:ffff:ffff:ffff:ffff:ffff:ffff
235fe82:cea0::/28fe82:ceaf:ffff:ffff:ffff:ffff:ffff:ffff
236fe82:ceb0::/28fe82:cebf:ffff:ffff:ffff:ffff:ffff:ffff
237fe82:cec0::/28fe82:cecf:ffff:ffff:ffff:ffff:ffff:ffff
238fe82:ced0::/28fe82:cedf:ffff:ffff:ffff:ffff:ffff:ffff
239fe82:cee0::/28fe82:ceef:ffff:ffff:ffff:ffff:ffff:ffff
240fe82:cef0::/28fe82:ceff:ffff:ffff:ffff:ffff:ffff:ffff
241fe82:cf00::/28fe82:cf0f:ffff:ffff:ffff:ffff:ffff:ffff
242fe82:cf10::/28fe82:cf1f:ffff:ffff:ffff:ffff:ffff:ffff
243fe82:cf20::/28fe82:cf2f:ffff:ffff:ffff:ffff:ffff:ffff
244fe82:cf30::/28fe82:cf3f:ffff:ffff:ffff:ffff:ffff:ffff
245fe82:cf40::/28fe82:cf4f:ffff:ffff:ffff:ffff:ffff:ffff
246fe82:cf50::/28fe82:cf5f:ffff:ffff:ffff:ffff:ffff:ffff
247fe82:cf60::/28fe82:cf6f:ffff:ffff:ffff:ffff:ffff:ffff
248fe82:cf70::/28fe82:cf7f:ffff:ffff:ffff:ffff:ffff:ffff
249fe82:cf80::/28fe82:cf8f:ffff:ffff:ffff:ffff:ffff:ffff
250fe82:cf90::/28fe82:cf9f:ffff:ffff:ffff:ffff:ffff:ffff
251fe82:cfa0::/28fe82:cfaf:ffff:ffff:ffff:ffff:ffff:ffff
252fe82:cfb0::/28fe82:cfbf:ffff:ffff:ffff:ffff:ffff:ffff
253fe82:cfc0::/28fe82:cfcf:ffff:ffff:ffff:ffff:ffff:ffff
254fe82:cfd0::/28fe82:cfdf:ffff:ffff:ffff:ffff:ffff:ffff
255fe82:cfe0::/28fe82:cfef:ffff:ffff:ffff:ffff:ffff:ffff
256fe82:cff0::/28fe82: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.