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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/16
Addresses2^112
/64 networks2^48
Network
fea2::/16
First address
fea2::
Last address
fea2: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
fea2:0000:0000:0000:0000:0000:0000:0000
Type
Link-local fe80::/10
Every IPv6 interface has one; not routed
Reverse DNS zone
2.a.e.f.ip6.arpa
Split into smaller subnets/28
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

fea2::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
1fea2::/28fea2:f:ffff:ffff:ffff:ffff:ffff:ffff
2fea2:10::/28fea2:1f:ffff:ffff:ffff:ffff:ffff:ffff
3fea2:20::/28fea2:2f:ffff:ffff:ffff:ffff:ffff:ffff
4fea2:30::/28fea2:3f:ffff:ffff:ffff:ffff:ffff:ffff
5fea2:40::/28fea2:4f:ffff:ffff:ffff:ffff:ffff:ffff
6fea2:50::/28fea2:5f:ffff:ffff:ffff:ffff:ffff:ffff
7fea2:60::/28fea2:6f:ffff:ffff:ffff:ffff:ffff:ffff
8fea2:70::/28fea2:7f:ffff:ffff:ffff:ffff:ffff:ffff
9fea2:80::/28fea2:8f:ffff:ffff:ffff:ffff:ffff:ffff
10fea2:90::/28fea2:9f:ffff:ffff:ffff:ffff:ffff:ffff
11fea2:a0::/28fea2:af:ffff:ffff:ffff:ffff:ffff:ffff
12fea2:b0::/28fea2:bf:ffff:ffff:ffff:ffff:ffff:ffff
13fea2:c0::/28fea2:cf:ffff:ffff:ffff:ffff:ffff:ffff
14fea2:d0::/28fea2:df:ffff:ffff:ffff:ffff:ffff:ffff
15fea2:e0::/28fea2:ef:ffff:ffff:ffff:ffff:ffff:ffff
16fea2:f0::/28fea2:ff:ffff:ffff:ffff:ffff:ffff:ffff
17fea2:100::/28fea2:10f:ffff:ffff:ffff:ffff:ffff:ffff
18fea2:110::/28fea2:11f:ffff:ffff:ffff:ffff:ffff:ffff
19fea2:120::/28fea2:12f:ffff:ffff:ffff:ffff:ffff:ffff
20fea2:130::/28fea2:13f:ffff:ffff:ffff:ffff:ffff:ffff
21fea2:140::/28fea2:14f:ffff:ffff:ffff:ffff:ffff:ffff
22fea2:150::/28fea2:15f:ffff:ffff:ffff:ffff:ffff:ffff
23fea2:160::/28fea2:16f:ffff:ffff:ffff:ffff:ffff:ffff
24fea2:170::/28fea2:17f:ffff:ffff:ffff:ffff:ffff:ffff
25fea2:180::/28fea2:18f:ffff:ffff:ffff:ffff:ffff:ffff
26fea2:190::/28fea2:19f:ffff:ffff:ffff:ffff:ffff:ffff
27fea2:1a0::/28fea2:1af:ffff:ffff:ffff:ffff:ffff:ffff
28fea2:1b0::/28fea2:1bf:ffff:ffff:ffff:ffff:ffff:ffff
29fea2:1c0::/28fea2:1cf:ffff:ffff:ffff:ffff:ffff:ffff
30fea2:1d0::/28fea2:1df:ffff:ffff:ffff:ffff:ffff:ffff
31fea2:1e0::/28fea2:1ef:ffff:ffff:ffff:ffff:ffff:ffff
32fea2:1f0::/28fea2:1ff:ffff:ffff:ffff:ffff:ffff:ffff
33fea2:200::/28fea2:20f:ffff:ffff:ffff:ffff:ffff:ffff
34fea2:210::/28fea2:21f:ffff:ffff:ffff:ffff:ffff:ffff
35fea2:220::/28fea2:22f:ffff:ffff:ffff:ffff:ffff:ffff
36fea2:230::/28fea2:23f:ffff:ffff:ffff:ffff:ffff:ffff
37fea2:240::/28fea2:24f:ffff:ffff:ffff:ffff:ffff:ffff
38fea2:250::/28fea2:25f:ffff:ffff:ffff:ffff:ffff:ffff
39fea2:260::/28fea2:26f:ffff:ffff:ffff:ffff:ffff:ffff
40fea2:270::/28fea2:27f:ffff:ffff:ffff:ffff:ffff:ffff
41fea2:280::/28fea2:28f:ffff:ffff:ffff:ffff:ffff:ffff
42fea2:290::/28fea2:29f:ffff:ffff:ffff:ffff:ffff:ffff
43fea2:2a0::/28fea2:2af:ffff:ffff:ffff:ffff:ffff:ffff
44fea2:2b0::/28fea2:2bf:ffff:ffff:ffff:ffff:ffff:ffff
45fea2:2c0::/28fea2:2cf:ffff:ffff:ffff:ffff:ffff:ffff
46fea2:2d0::/28fea2:2df:ffff:ffff:ffff:ffff:ffff:ffff
47fea2:2e0::/28fea2:2ef:ffff:ffff:ffff:ffff:ffff:ffff
48fea2:2f0::/28fea2:2ff:ffff:ffff:ffff:ffff:ffff:ffff
49fea2:300::/28fea2:30f:ffff:ffff:ffff:ffff:ffff:ffff
50fea2:310::/28fea2:31f:ffff:ffff:ffff:ffff:ffff:ffff
51fea2:320::/28fea2:32f:ffff:ffff:ffff:ffff:ffff:ffff
52fea2:330::/28fea2:33f:ffff:ffff:ffff:ffff:ffff:ffff
53fea2:340::/28fea2:34f:ffff:ffff:ffff:ffff:ffff:ffff
54fea2:350::/28fea2:35f:ffff:ffff:ffff:ffff:ffff:ffff
55fea2:360::/28fea2:36f:ffff:ffff:ffff:ffff:ffff:ffff
56fea2:370::/28fea2:37f:ffff:ffff:ffff:ffff:ffff:ffff
57fea2:380::/28fea2:38f:ffff:ffff:ffff:ffff:ffff:ffff
58fea2:390::/28fea2:39f:ffff:ffff:ffff:ffff:ffff:ffff
59fea2:3a0::/28fea2:3af:ffff:ffff:ffff:ffff:ffff:ffff
60fea2:3b0::/28fea2:3bf:ffff:ffff:ffff:ffff:ffff:ffff
61fea2:3c0::/28fea2:3cf:ffff:ffff:ffff:ffff:ffff:ffff
62fea2:3d0::/28fea2:3df:ffff:ffff:ffff:ffff:ffff:ffff
63fea2:3e0::/28fea2:3ef:ffff:ffff:ffff:ffff:ffff:ffff
64fea2:3f0::/28fea2:3ff:ffff:ffff:ffff:ffff:ffff:ffff
65fea2:400::/28fea2:40f:ffff:ffff:ffff:ffff:ffff:ffff
66fea2:410::/28fea2:41f:ffff:ffff:ffff:ffff:ffff:ffff
67fea2:420::/28fea2:42f:ffff:ffff:ffff:ffff:ffff:ffff
68fea2:430::/28fea2:43f:ffff:ffff:ffff:ffff:ffff:ffff
69fea2:440::/28fea2:44f:ffff:ffff:ffff:ffff:ffff:ffff
70fea2:450::/28fea2:45f:ffff:ffff:ffff:ffff:ffff:ffff
71fea2:460::/28fea2:46f:ffff:ffff:ffff:ffff:ffff:ffff
72fea2:470::/28fea2:47f:ffff:ffff:ffff:ffff:ffff:ffff
73fea2:480::/28fea2:48f:ffff:ffff:ffff:ffff:ffff:ffff
74fea2:490::/28fea2:49f:ffff:ffff:ffff:ffff:ffff:ffff
75fea2:4a0::/28fea2:4af:ffff:ffff:ffff:ffff:ffff:ffff
76fea2:4b0::/28fea2:4bf:ffff:ffff:ffff:ffff:ffff:ffff
77fea2:4c0::/28fea2:4cf:ffff:ffff:ffff:ffff:ffff:ffff
78fea2:4d0::/28fea2:4df:ffff:ffff:ffff:ffff:ffff:ffff
79fea2:4e0::/28fea2:4ef:ffff:ffff:ffff:ffff:ffff:ffff
80fea2:4f0::/28fea2:4ff:ffff:ffff:ffff:ffff:ffff:ffff
81fea2:500::/28fea2:50f:ffff:ffff:ffff:ffff:ffff:ffff
82fea2:510::/28fea2:51f:ffff:ffff:ffff:ffff:ffff:ffff
83fea2:520::/28fea2:52f:ffff:ffff:ffff:ffff:ffff:ffff
84fea2:530::/28fea2:53f:ffff:ffff:ffff:ffff:ffff:ffff
85fea2:540::/28fea2:54f:ffff:ffff:ffff:ffff:ffff:ffff
86fea2:550::/28fea2:55f:ffff:ffff:ffff:ffff:ffff:ffff
87fea2:560::/28fea2:56f:ffff:ffff:ffff:ffff:ffff:ffff
88fea2:570::/28fea2:57f:ffff:ffff:ffff:ffff:ffff:ffff
89fea2:580::/28fea2:58f:ffff:ffff:ffff:ffff:ffff:ffff
90fea2:590::/28fea2:59f:ffff:ffff:ffff:ffff:ffff:ffff
91fea2:5a0::/28fea2:5af:ffff:ffff:ffff:ffff:ffff:ffff
92fea2:5b0::/28fea2:5bf:ffff:ffff:ffff:ffff:ffff:ffff
93fea2:5c0::/28fea2:5cf:ffff:ffff:ffff:ffff:ffff:ffff
94fea2:5d0::/28fea2:5df:ffff:ffff:ffff:ffff:ffff:ffff
95fea2:5e0::/28fea2:5ef:ffff:ffff:ffff:ffff:ffff:ffff
96fea2:5f0::/28fea2:5ff:ffff:ffff:ffff:ffff:ffff:ffff
97fea2:600::/28fea2:60f:ffff:ffff:ffff:ffff:ffff:ffff
98fea2:610::/28fea2:61f:ffff:ffff:ffff:ffff:ffff:ffff
99fea2:620::/28fea2:62f:ffff:ffff:ffff:ffff:ffff:ffff
100fea2:630::/28fea2:63f:ffff:ffff:ffff:ffff:ffff:ffff
101fea2:640::/28fea2:64f:ffff:ffff:ffff:ffff:ffff:ffff
102fea2:650::/28fea2:65f:ffff:ffff:ffff:ffff:ffff:ffff
103fea2:660::/28fea2:66f:ffff:ffff:ffff:ffff:ffff:ffff
104fea2:670::/28fea2:67f:ffff:ffff:ffff:ffff:ffff:ffff
105fea2:680::/28fea2:68f:ffff:ffff:ffff:ffff:ffff:ffff
106fea2:690::/28fea2:69f:ffff:ffff:ffff:ffff:ffff:ffff
107fea2:6a0::/28fea2:6af:ffff:ffff:ffff:ffff:ffff:ffff
108fea2:6b0::/28fea2:6bf:ffff:ffff:ffff:ffff:ffff:ffff
109fea2:6c0::/28fea2:6cf:ffff:ffff:ffff:ffff:ffff:ffff
110fea2:6d0::/28fea2:6df:ffff:ffff:ffff:ffff:ffff:ffff
111fea2:6e0::/28fea2:6ef:ffff:ffff:ffff:ffff:ffff:ffff
112fea2:6f0::/28fea2:6ff:ffff:ffff:ffff:ffff:ffff:ffff
113fea2:700::/28fea2:70f:ffff:ffff:ffff:ffff:ffff:ffff
114fea2:710::/28fea2:71f:ffff:ffff:ffff:ffff:ffff:ffff
115fea2:720::/28fea2:72f:ffff:ffff:ffff:ffff:ffff:ffff
116fea2:730::/28fea2:73f:ffff:ffff:ffff:ffff:ffff:ffff
117fea2:740::/28fea2:74f:ffff:ffff:ffff:ffff:ffff:ffff
118fea2:750::/28fea2:75f:ffff:ffff:ffff:ffff:ffff:ffff
119fea2:760::/28fea2:76f:ffff:ffff:ffff:ffff:ffff:ffff
120fea2:770::/28fea2:77f:ffff:ffff:ffff:ffff:ffff:ffff
121fea2:780::/28fea2:78f:ffff:ffff:ffff:ffff:ffff:ffff
122fea2:790::/28fea2:79f:ffff:ffff:ffff:ffff:ffff:ffff
123fea2:7a0::/28fea2:7af:ffff:ffff:ffff:ffff:ffff:ffff
124fea2:7b0::/28fea2:7bf:ffff:ffff:ffff:ffff:ffff:ffff
125fea2:7c0::/28fea2:7cf:ffff:ffff:ffff:ffff:ffff:ffff
126fea2:7d0::/28fea2:7df:ffff:ffff:ffff:ffff:ffff:ffff
127fea2:7e0::/28fea2:7ef:ffff:ffff:ffff:ffff:ffff:ffff
128fea2:7f0::/28fea2:7ff:ffff:ffff:ffff:ffff:ffff:ffff
129fea2:800::/28fea2:80f:ffff:ffff:ffff:ffff:ffff:ffff
130fea2:810::/28fea2:81f:ffff:ffff:ffff:ffff:ffff:ffff
131fea2:820::/28fea2:82f:ffff:ffff:ffff:ffff:ffff:ffff
132fea2:830::/28fea2:83f:ffff:ffff:ffff:ffff:ffff:ffff
133fea2:840::/28fea2:84f:ffff:ffff:ffff:ffff:ffff:ffff
134fea2:850::/28fea2:85f:ffff:ffff:ffff:ffff:ffff:ffff
135fea2:860::/28fea2:86f:ffff:ffff:ffff:ffff:ffff:ffff
136fea2:870::/28fea2:87f:ffff:ffff:ffff:ffff:ffff:ffff
137fea2:880::/28fea2:88f:ffff:ffff:ffff:ffff:ffff:ffff
138fea2:890::/28fea2:89f:ffff:ffff:ffff:ffff:ffff:ffff
139fea2:8a0::/28fea2:8af:ffff:ffff:ffff:ffff:ffff:ffff
140fea2:8b0::/28fea2:8bf:ffff:ffff:ffff:ffff:ffff:ffff
141fea2:8c0::/28fea2:8cf:ffff:ffff:ffff:ffff:ffff:ffff
142fea2:8d0::/28fea2:8df:ffff:ffff:ffff:ffff:ffff:ffff
143fea2:8e0::/28fea2:8ef:ffff:ffff:ffff:ffff:ffff:ffff
144fea2:8f0::/28fea2:8ff:ffff:ffff:ffff:ffff:ffff:ffff
145fea2:900::/28fea2:90f:ffff:ffff:ffff:ffff:ffff:ffff
146fea2:910::/28fea2:91f:ffff:ffff:ffff:ffff:ffff:ffff
147fea2:920::/28fea2:92f:ffff:ffff:ffff:ffff:ffff:ffff
148fea2:930::/28fea2:93f:ffff:ffff:ffff:ffff:ffff:ffff
149fea2:940::/28fea2:94f:ffff:ffff:ffff:ffff:ffff:ffff
150fea2:950::/28fea2:95f:ffff:ffff:ffff:ffff:ffff:ffff
151fea2:960::/28fea2:96f:ffff:ffff:ffff:ffff:ffff:ffff
152fea2:970::/28fea2:97f:ffff:ffff:ffff:ffff:ffff:ffff
153fea2:980::/28fea2:98f:ffff:ffff:ffff:ffff:ffff:ffff
154fea2:990::/28fea2:99f:ffff:ffff:ffff:ffff:ffff:ffff
155fea2:9a0::/28fea2:9af:ffff:ffff:ffff:ffff:ffff:ffff
156fea2:9b0::/28fea2:9bf:ffff:ffff:ffff:ffff:ffff:ffff
157fea2:9c0::/28fea2:9cf:ffff:ffff:ffff:ffff:ffff:ffff
158fea2:9d0::/28fea2:9df:ffff:ffff:ffff:ffff:ffff:ffff
159fea2:9e0::/28fea2:9ef:ffff:ffff:ffff:ffff:ffff:ffff
160fea2:9f0::/28fea2:9ff:ffff:ffff:ffff:ffff:ffff:ffff
161fea2:a00::/28fea2:a0f:ffff:ffff:ffff:ffff:ffff:ffff
162fea2:a10::/28fea2:a1f:ffff:ffff:ffff:ffff:ffff:ffff
163fea2:a20::/28fea2:a2f:ffff:ffff:ffff:ffff:ffff:ffff
164fea2:a30::/28fea2:a3f:ffff:ffff:ffff:ffff:ffff:ffff
165fea2:a40::/28fea2:a4f:ffff:ffff:ffff:ffff:ffff:ffff
166fea2:a50::/28fea2:a5f:ffff:ffff:ffff:ffff:ffff:ffff
167fea2:a60::/28fea2:a6f:ffff:ffff:ffff:ffff:ffff:ffff
168fea2:a70::/28fea2:a7f:ffff:ffff:ffff:ffff:ffff:ffff
169fea2:a80::/28fea2:a8f:ffff:ffff:ffff:ffff:ffff:ffff
170fea2:a90::/28fea2:a9f:ffff:ffff:ffff:ffff:ffff:ffff
171fea2:aa0::/28fea2:aaf:ffff:ffff:ffff:ffff:ffff:ffff
172fea2:ab0::/28fea2:abf:ffff:ffff:ffff:ffff:ffff:ffff
173fea2:ac0::/28fea2:acf:ffff:ffff:ffff:ffff:ffff:ffff
174fea2:ad0::/28fea2:adf:ffff:ffff:ffff:ffff:ffff:ffff
175fea2:ae0::/28fea2:aef:ffff:ffff:ffff:ffff:ffff:ffff
176fea2:af0::/28fea2:aff:ffff:ffff:ffff:ffff:ffff:ffff
177fea2:b00::/28fea2:b0f:ffff:ffff:ffff:ffff:ffff:ffff
178fea2:b10::/28fea2:b1f:ffff:ffff:ffff:ffff:ffff:ffff
179fea2:b20::/28fea2:b2f:ffff:ffff:ffff:ffff:ffff:ffff
180fea2:b30::/28fea2:b3f:ffff:ffff:ffff:ffff:ffff:ffff
181fea2:b40::/28fea2:b4f:ffff:ffff:ffff:ffff:ffff:ffff
182fea2:b50::/28fea2:b5f:ffff:ffff:ffff:ffff:ffff:ffff
183fea2:b60::/28fea2:b6f:ffff:ffff:ffff:ffff:ffff:ffff
184fea2:b70::/28fea2:b7f:ffff:ffff:ffff:ffff:ffff:ffff
185fea2:b80::/28fea2:b8f:ffff:ffff:ffff:ffff:ffff:ffff
186fea2:b90::/28fea2:b9f:ffff:ffff:ffff:ffff:ffff:ffff
187fea2:ba0::/28fea2:baf:ffff:ffff:ffff:ffff:ffff:ffff
188fea2:bb0::/28fea2:bbf:ffff:ffff:ffff:ffff:ffff:ffff
189fea2:bc0::/28fea2:bcf:ffff:ffff:ffff:ffff:ffff:ffff
190fea2:bd0::/28fea2:bdf:ffff:ffff:ffff:ffff:ffff:ffff
191fea2:be0::/28fea2:bef:ffff:ffff:ffff:ffff:ffff:ffff
192fea2:bf0::/28fea2:bff:ffff:ffff:ffff:ffff:ffff:ffff
193fea2:c00::/28fea2:c0f:ffff:ffff:ffff:ffff:ffff:ffff
194fea2:c10::/28fea2:c1f:ffff:ffff:ffff:ffff:ffff:ffff
195fea2:c20::/28fea2:c2f:ffff:ffff:ffff:ffff:ffff:ffff
196fea2:c30::/28fea2:c3f:ffff:ffff:ffff:ffff:ffff:ffff
197fea2:c40::/28fea2:c4f:ffff:ffff:ffff:ffff:ffff:ffff
198fea2:c50::/28fea2:c5f:ffff:ffff:ffff:ffff:ffff:ffff
199fea2:c60::/28fea2:c6f:ffff:ffff:ffff:ffff:ffff:ffff
200fea2:c70::/28fea2:c7f:ffff:ffff:ffff:ffff:ffff:ffff
201fea2:c80::/28fea2:c8f:ffff:ffff:ffff:ffff:ffff:ffff
202fea2:c90::/28fea2:c9f:ffff:ffff:ffff:ffff:ffff:ffff
203fea2:ca0::/28fea2:caf:ffff:ffff:ffff:ffff:ffff:ffff
204fea2:cb0::/28fea2:cbf:ffff:ffff:ffff:ffff:ffff:ffff
205fea2:cc0::/28fea2:ccf:ffff:ffff:ffff:ffff:ffff:ffff
206fea2:cd0::/28fea2:cdf:ffff:ffff:ffff:ffff:ffff:ffff
207fea2:ce0::/28fea2:cef:ffff:ffff:ffff:ffff:ffff:ffff
208fea2:cf0::/28fea2:cff:ffff:ffff:ffff:ffff:ffff:ffff
209fea2:d00::/28fea2:d0f:ffff:ffff:ffff:ffff:ffff:ffff
210fea2:d10::/28fea2:d1f:ffff:ffff:ffff:ffff:ffff:ffff
211fea2:d20::/28fea2:d2f:ffff:ffff:ffff:ffff:ffff:ffff
212fea2:d30::/28fea2:d3f:ffff:ffff:ffff:ffff:ffff:ffff
213fea2:d40::/28fea2:d4f:ffff:ffff:ffff:ffff:ffff:ffff
214fea2:d50::/28fea2:d5f:ffff:ffff:ffff:ffff:ffff:ffff
215fea2:d60::/28fea2:d6f:ffff:ffff:ffff:ffff:ffff:ffff
216fea2:d70::/28fea2:d7f:ffff:ffff:ffff:ffff:ffff:ffff
217fea2:d80::/28fea2:d8f:ffff:ffff:ffff:ffff:ffff:ffff
218fea2:d90::/28fea2:d9f:ffff:ffff:ffff:ffff:ffff:ffff
219fea2:da0::/28fea2:daf:ffff:ffff:ffff:ffff:ffff:ffff
220fea2:db0::/28fea2:dbf:ffff:ffff:ffff:ffff:ffff:ffff
221fea2:dc0::/28fea2:dcf:ffff:ffff:ffff:ffff:ffff:ffff
222fea2:dd0::/28fea2:ddf:ffff:ffff:ffff:ffff:ffff:ffff
223fea2:de0::/28fea2:def:ffff:ffff:ffff:ffff:ffff:ffff
224fea2:df0::/28fea2:dff:ffff:ffff:ffff:ffff:ffff:ffff
225fea2:e00::/28fea2:e0f:ffff:ffff:ffff:ffff:ffff:ffff
226fea2:e10::/28fea2:e1f:ffff:ffff:ffff:ffff:ffff:ffff
227fea2:e20::/28fea2:e2f:ffff:ffff:ffff:ffff:ffff:ffff
228fea2:e30::/28fea2:e3f:ffff:ffff:ffff:ffff:ffff:ffff
229fea2:e40::/28fea2:e4f:ffff:ffff:ffff:ffff:ffff:ffff
230fea2:e50::/28fea2:e5f:ffff:ffff:ffff:ffff:ffff:ffff
231fea2:e60::/28fea2:e6f:ffff:ffff:ffff:ffff:ffff:ffff
232fea2:e70::/28fea2:e7f:ffff:ffff:ffff:ffff:ffff:ffff
233fea2:e80::/28fea2:e8f:ffff:ffff:ffff:ffff:ffff:ffff
234fea2:e90::/28fea2:e9f:ffff:ffff:ffff:ffff:ffff:ffff
235fea2:ea0::/28fea2:eaf:ffff:ffff:ffff:ffff:ffff:ffff
236fea2:eb0::/28fea2:ebf:ffff:ffff:ffff:ffff:ffff:ffff
237fea2:ec0::/28fea2:ecf:ffff:ffff:ffff:ffff:ffff:ffff
238fea2:ed0::/28fea2:edf:ffff:ffff:ffff:ffff:ffff:ffff
239fea2:ee0::/28fea2:eef:ffff:ffff:ffff:ffff:ffff:ffff
240fea2:ef0::/28fea2:eff:ffff:ffff:ffff:ffff:ffff:ffff
241fea2:f00::/28fea2:f0f:ffff:ffff:ffff:ffff:ffff:ffff
242fea2:f10::/28fea2:f1f:ffff:ffff:ffff:ffff:ffff:ffff
243fea2:f20::/28fea2:f2f:ffff:ffff:ffff:ffff:ffff:ffff
244fea2:f30::/28fea2:f3f:ffff:ffff:ffff:ffff:ffff:ffff
245fea2:f40::/28fea2:f4f:ffff:ffff:ffff:ffff:ffff:ffff
246fea2:f50::/28fea2:f5f:ffff:ffff:ffff:ffff:ffff:ffff
247fea2:f60::/28fea2:f6f:ffff:ffff:ffff:ffff:ffff:ffff
248fea2:f70::/28fea2:f7f:ffff:ffff:ffff:ffff:ffff:ffff
249fea2:f80::/28fea2:f8f:ffff:ffff:ffff:ffff:ffff:ffff
250fea2:f90::/28fea2:f9f:ffff:ffff:ffff:ffff:ffff:ffff
251fea2:fa0::/28fea2:faf:ffff:ffff:ffff:ffff:ffff:ffff
252fea2:fb0::/28fea2:fbf:ffff:ffff:ffff:ffff:ffff:ffff
253fea2:fc0::/28fea2:fcf:ffff:ffff:ffff:ffff:ffff:ffff
254fea2:fd0::/28fea2:fdf:ffff:ffff:ffff:ffff:ffff:ffff
255fea2:fe0::/28fea2:fef:ffff:ffff:ffff:ffff:ffff:ffff
256fea2:ff0::/28fea2: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.