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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/32
Addresses2^96
/64 networks2^32
Network
febe:dd::/32
First address
febe:dd::
Last address
febe:dd:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
79,228,162,514,264,337,593,543,950,336 (2^96)
/64 networks (LANs)
4,294,967,296
Full form
febe:00dd:0000:0000:0000:0000:0000:0000
Type
Link-local fe80::/10
Every IPv6 interface has one; not routed
Reverse DNS zone
d.d.0.0.e.b.e.f.ip6.arpa
Split into smaller subnets/44
/33 (2)/34 (4)/35 (8)/36 (16)/40 (256)/44 (4,096)/48 (65,536)

febe:dd::/32 makes 4,096 subnets of /44; the first 256 are listed.

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