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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
feb2::/16
First address
feb2::
Last address
feb2: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
feb2:0000:0000:0000:0000:0000:0000:0000
Type
Link-local fe80::/10
Every IPv6 interface has one; not routed
Reverse DNS zone
2.b.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)

feb2::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
1feb2::/28feb2:f:ffff:ffff:ffff:ffff:ffff:ffff
2feb2:10::/28feb2:1f:ffff:ffff:ffff:ffff:ffff:ffff
3feb2:20::/28feb2:2f:ffff:ffff:ffff:ffff:ffff:ffff
4feb2:30::/28feb2:3f:ffff:ffff:ffff:ffff:ffff:ffff
5feb2:40::/28feb2:4f:ffff:ffff:ffff:ffff:ffff:ffff
6feb2:50::/28feb2:5f:ffff:ffff:ffff:ffff:ffff:ffff
7feb2:60::/28feb2:6f:ffff:ffff:ffff:ffff:ffff:ffff
8feb2:70::/28feb2:7f:ffff:ffff:ffff:ffff:ffff:ffff
9feb2:80::/28feb2:8f:ffff:ffff:ffff:ffff:ffff:ffff
10feb2:90::/28feb2:9f:ffff:ffff:ffff:ffff:ffff:ffff
11feb2:a0::/28feb2:af:ffff:ffff:ffff:ffff:ffff:ffff
12feb2:b0::/28feb2:bf:ffff:ffff:ffff:ffff:ffff:ffff
13feb2:c0::/28feb2:cf:ffff:ffff:ffff:ffff:ffff:ffff
14feb2:d0::/28feb2:df:ffff:ffff:ffff:ffff:ffff:ffff
15feb2:e0::/28feb2:ef:ffff:ffff:ffff:ffff:ffff:ffff
16feb2:f0::/28feb2:ff:ffff:ffff:ffff:ffff:ffff:ffff
17feb2:100::/28feb2:10f:ffff:ffff:ffff:ffff:ffff:ffff
18feb2:110::/28feb2:11f:ffff:ffff:ffff:ffff:ffff:ffff
19feb2:120::/28feb2:12f:ffff:ffff:ffff:ffff:ffff:ffff
20feb2:130::/28feb2:13f:ffff:ffff:ffff:ffff:ffff:ffff
21feb2:140::/28feb2:14f:ffff:ffff:ffff:ffff:ffff:ffff
22feb2:150::/28feb2:15f:ffff:ffff:ffff:ffff:ffff:ffff
23feb2:160::/28feb2:16f:ffff:ffff:ffff:ffff:ffff:ffff
24feb2:170::/28feb2:17f:ffff:ffff:ffff:ffff:ffff:ffff
25feb2:180::/28feb2:18f:ffff:ffff:ffff:ffff:ffff:ffff
26feb2:190::/28feb2:19f:ffff:ffff:ffff:ffff:ffff:ffff
27feb2:1a0::/28feb2:1af:ffff:ffff:ffff:ffff:ffff:ffff
28feb2:1b0::/28feb2:1bf:ffff:ffff:ffff:ffff:ffff:ffff
29feb2:1c0::/28feb2:1cf:ffff:ffff:ffff:ffff:ffff:ffff
30feb2:1d0::/28feb2:1df:ffff:ffff:ffff:ffff:ffff:ffff
31feb2:1e0::/28feb2:1ef:ffff:ffff:ffff:ffff:ffff:ffff
32feb2:1f0::/28feb2:1ff:ffff:ffff:ffff:ffff:ffff:ffff
33feb2:200::/28feb2:20f:ffff:ffff:ffff:ffff:ffff:ffff
34feb2:210::/28feb2:21f:ffff:ffff:ffff:ffff:ffff:ffff
35feb2:220::/28feb2:22f:ffff:ffff:ffff:ffff:ffff:ffff
36feb2:230::/28feb2:23f:ffff:ffff:ffff:ffff:ffff:ffff
37feb2:240::/28feb2:24f:ffff:ffff:ffff:ffff:ffff:ffff
38feb2:250::/28feb2:25f:ffff:ffff:ffff:ffff:ffff:ffff
39feb2:260::/28feb2:26f:ffff:ffff:ffff:ffff:ffff:ffff
40feb2:270::/28feb2:27f:ffff:ffff:ffff:ffff:ffff:ffff
41feb2:280::/28feb2:28f:ffff:ffff:ffff:ffff:ffff:ffff
42feb2:290::/28feb2:29f:ffff:ffff:ffff:ffff:ffff:ffff
43feb2:2a0::/28feb2:2af:ffff:ffff:ffff:ffff:ffff:ffff
44feb2:2b0::/28feb2:2bf:ffff:ffff:ffff:ffff:ffff:ffff
45feb2:2c0::/28feb2:2cf:ffff:ffff:ffff:ffff:ffff:ffff
46feb2:2d0::/28feb2:2df:ffff:ffff:ffff:ffff:ffff:ffff
47feb2:2e0::/28feb2:2ef:ffff:ffff:ffff:ffff:ffff:ffff
48feb2:2f0::/28feb2:2ff:ffff:ffff:ffff:ffff:ffff:ffff
49feb2:300::/28feb2:30f:ffff:ffff:ffff:ffff:ffff:ffff
50feb2:310::/28feb2:31f:ffff:ffff:ffff:ffff:ffff:ffff
51feb2:320::/28feb2:32f:ffff:ffff:ffff:ffff:ffff:ffff
52feb2:330::/28feb2:33f:ffff:ffff:ffff:ffff:ffff:ffff
53feb2:340::/28feb2:34f:ffff:ffff:ffff:ffff:ffff:ffff
54feb2:350::/28feb2:35f:ffff:ffff:ffff:ffff:ffff:ffff
55feb2:360::/28feb2:36f:ffff:ffff:ffff:ffff:ffff:ffff
56feb2:370::/28feb2:37f:ffff:ffff:ffff:ffff:ffff:ffff
57feb2:380::/28feb2:38f:ffff:ffff:ffff:ffff:ffff:ffff
58feb2:390::/28feb2:39f:ffff:ffff:ffff:ffff:ffff:ffff
59feb2:3a0::/28feb2:3af:ffff:ffff:ffff:ffff:ffff:ffff
60feb2:3b0::/28feb2:3bf:ffff:ffff:ffff:ffff:ffff:ffff
61feb2:3c0::/28feb2:3cf:ffff:ffff:ffff:ffff:ffff:ffff
62feb2:3d0::/28feb2:3df:ffff:ffff:ffff:ffff:ffff:ffff
63feb2:3e0::/28feb2:3ef:ffff:ffff:ffff:ffff:ffff:ffff
64feb2:3f0::/28feb2:3ff:ffff:ffff:ffff:ffff:ffff:ffff
65feb2:400::/28feb2:40f:ffff:ffff:ffff:ffff:ffff:ffff
66feb2:410::/28feb2:41f:ffff:ffff:ffff:ffff:ffff:ffff
67feb2:420::/28feb2:42f:ffff:ffff:ffff:ffff:ffff:ffff
68feb2:430::/28feb2:43f:ffff:ffff:ffff:ffff:ffff:ffff
69feb2:440::/28feb2:44f:ffff:ffff:ffff:ffff:ffff:ffff
70feb2:450::/28feb2:45f:ffff:ffff:ffff:ffff:ffff:ffff
71feb2:460::/28feb2:46f:ffff:ffff:ffff:ffff:ffff:ffff
72feb2:470::/28feb2:47f:ffff:ffff:ffff:ffff:ffff:ffff
73feb2:480::/28feb2:48f:ffff:ffff:ffff:ffff:ffff:ffff
74feb2:490::/28feb2:49f:ffff:ffff:ffff:ffff:ffff:ffff
75feb2:4a0::/28feb2:4af:ffff:ffff:ffff:ffff:ffff:ffff
76feb2:4b0::/28feb2:4bf:ffff:ffff:ffff:ffff:ffff:ffff
77feb2:4c0::/28feb2:4cf:ffff:ffff:ffff:ffff:ffff:ffff
78feb2:4d0::/28feb2:4df:ffff:ffff:ffff:ffff:ffff:ffff
79feb2:4e0::/28feb2:4ef:ffff:ffff:ffff:ffff:ffff:ffff
80feb2:4f0::/28feb2:4ff:ffff:ffff:ffff:ffff:ffff:ffff
81feb2:500::/28feb2:50f:ffff:ffff:ffff:ffff:ffff:ffff
82feb2:510::/28feb2:51f:ffff:ffff:ffff:ffff:ffff:ffff
83feb2:520::/28feb2:52f:ffff:ffff:ffff:ffff:ffff:ffff
84feb2:530::/28feb2:53f:ffff:ffff:ffff:ffff:ffff:ffff
85feb2:540::/28feb2:54f:ffff:ffff:ffff:ffff:ffff:ffff
86feb2:550::/28feb2:55f:ffff:ffff:ffff:ffff:ffff:ffff
87feb2:560::/28feb2:56f:ffff:ffff:ffff:ffff:ffff:ffff
88feb2:570::/28feb2:57f:ffff:ffff:ffff:ffff:ffff:ffff
89feb2:580::/28feb2:58f:ffff:ffff:ffff:ffff:ffff:ffff
90feb2:590::/28feb2:59f:ffff:ffff:ffff:ffff:ffff:ffff
91feb2:5a0::/28feb2:5af:ffff:ffff:ffff:ffff:ffff:ffff
92feb2:5b0::/28feb2:5bf:ffff:ffff:ffff:ffff:ffff:ffff
93feb2:5c0::/28feb2:5cf:ffff:ffff:ffff:ffff:ffff:ffff
94feb2:5d0::/28feb2:5df:ffff:ffff:ffff:ffff:ffff:ffff
95feb2:5e0::/28feb2:5ef:ffff:ffff:ffff:ffff:ffff:ffff
96feb2:5f0::/28feb2:5ff:ffff:ffff:ffff:ffff:ffff:ffff
97feb2:600::/28feb2:60f:ffff:ffff:ffff:ffff:ffff:ffff
98feb2:610::/28feb2:61f:ffff:ffff:ffff:ffff:ffff:ffff
99feb2:620::/28feb2:62f:ffff:ffff:ffff:ffff:ffff:ffff
100feb2:630::/28feb2:63f:ffff:ffff:ffff:ffff:ffff:ffff
101feb2:640::/28feb2:64f:ffff:ffff:ffff:ffff:ffff:ffff
102feb2:650::/28feb2:65f:ffff:ffff:ffff:ffff:ffff:ffff
103feb2:660::/28feb2:66f:ffff:ffff:ffff:ffff:ffff:ffff
104feb2:670::/28feb2:67f:ffff:ffff:ffff:ffff:ffff:ffff
105feb2:680::/28feb2:68f:ffff:ffff:ffff:ffff:ffff:ffff
106feb2:690::/28feb2:69f:ffff:ffff:ffff:ffff:ffff:ffff
107feb2:6a0::/28feb2:6af:ffff:ffff:ffff:ffff:ffff:ffff
108feb2:6b0::/28feb2:6bf:ffff:ffff:ffff:ffff:ffff:ffff
109feb2:6c0::/28feb2:6cf:ffff:ffff:ffff:ffff:ffff:ffff
110feb2:6d0::/28feb2:6df:ffff:ffff:ffff:ffff:ffff:ffff
111feb2:6e0::/28feb2:6ef:ffff:ffff:ffff:ffff:ffff:ffff
112feb2:6f0::/28feb2:6ff:ffff:ffff:ffff:ffff:ffff:ffff
113feb2:700::/28feb2:70f:ffff:ffff:ffff:ffff:ffff:ffff
114feb2:710::/28feb2:71f:ffff:ffff:ffff:ffff:ffff:ffff
115feb2:720::/28feb2:72f:ffff:ffff:ffff:ffff:ffff:ffff
116feb2:730::/28feb2:73f:ffff:ffff:ffff:ffff:ffff:ffff
117feb2:740::/28feb2:74f:ffff:ffff:ffff:ffff:ffff:ffff
118feb2:750::/28feb2:75f:ffff:ffff:ffff:ffff:ffff:ffff
119feb2:760::/28feb2:76f:ffff:ffff:ffff:ffff:ffff:ffff
120feb2:770::/28feb2:77f:ffff:ffff:ffff:ffff:ffff:ffff
121feb2:780::/28feb2:78f:ffff:ffff:ffff:ffff:ffff:ffff
122feb2:790::/28feb2:79f:ffff:ffff:ffff:ffff:ffff:ffff
123feb2:7a0::/28feb2:7af:ffff:ffff:ffff:ffff:ffff:ffff
124feb2:7b0::/28feb2:7bf:ffff:ffff:ffff:ffff:ffff:ffff
125feb2:7c0::/28feb2:7cf:ffff:ffff:ffff:ffff:ffff:ffff
126feb2:7d0::/28feb2:7df:ffff:ffff:ffff:ffff:ffff:ffff
127feb2:7e0::/28feb2:7ef:ffff:ffff:ffff:ffff:ffff:ffff
128feb2:7f0::/28feb2:7ff:ffff:ffff:ffff:ffff:ffff:ffff
129feb2:800::/28feb2:80f:ffff:ffff:ffff:ffff:ffff:ffff
130feb2:810::/28feb2:81f:ffff:ffff:ffff:ffff:ffff:ffff
131feb2:820::/28feb2:82f:ffff:ffff:ffff:ffff:ffff:ffff
132feb2:830::/28feb2:83f:ffff:ffff:ffff:ffff:ffff:ffff
133feb2:840::/28feb2:84f:ffff:ffff:ffff:ffff:ffff:ffff
134feb2:850::/28feb2:85f:ffff:ffff:ffff:ffff:ffff:ffff
135feb2:860::/28feb2:86f:ffff:ffff:ffff:ffff:ffff:ffff
136feb2:870::/28feb2:87f:ffff:ffff:ffff:ffff:ffff:ffff
137feb2:880::/28feb2:88f:ffff:ffff:ffff:ffff:ffff:ffff
138feb2:890::/28feb2:89f:ffff:ffff:ffff:ffff:ffff:ffff
139feb2:8a0::/28feb2:8af:ffff:ffff:ffff:ffff:ffff:ffff
140feb2:8b0::/28feb2:8bf:ffff:ffff:ffff:ffff:ffff:ffff
141feb2:8c0::/28feb2:8cf:ffff:ffff:ffff:ffff:ffff:ffff
142feb2:8d0::/28feb2:8df:ffff:ffff:ffff:ffff:ffff:ffff
143feb2:8e0::/28feb2:8ef:ffff:ffff:ffff:ffff:ffff:ffff
144feb2:8f0::/28feb2:8ff:ffff:ffff:ffff:ffff:ffff:ffff
145feb2:900::/28feb2:90f:ffff:ffff:ffff:ffff:ffff:ffff
146feb2:910::/28feb2:91f:ffff:ffff:ffff:ffff:ffff:ffff
147feb2:920::/28feb2:92f:ffff:ffff:ffff:ffff:ffff:ffff
148feb2:930::/28feb2:93f:ffff:ffff:ffff:ffff:ffff:ffff
149feb2:940::/28feb2:94f:ffff:ffff:ffff:ffff:ffff:ffff
150feb2:950::/28feb2:95f:ffff:ffff:ffff:ffff:ffff:ffff
151feb2:960::/28feb2:96f:ffff:ffff:ffff:ffff:ffff:ffff
152feb2:970::/28feb2:97f:ffff:ffff:ffff:ffff:ffff:ffff
153feb2:980::/28feb2:98f:ffff:ffff:ffff:ffff:ffff:ffff
154feb2:990::/28feb2:99f:ffff:ffff:ffff:ffff:ffff:ffff
155feb2:9a0::/28feb2:9af:ffff:ffff:ffff:ffff:ffff:ffff
156feb2:9b0::/28feb2:9bf:ffff:ffff:ffff:ffff:ffff:ffff
157feb2:9c0::/28feb2:9cf:ffff:ffff:ffff:ffff:ffff:ffff
158feb2:9d0::/28feb2:9df:ffff:ffff:ffff:ffff:ffff:ffff
159feb2:9e0::/28feb2:9ef:ffff:ffff:ffff:ffff:ffff:ffff
160feb2:9f0::/28feb2:9ff:ffff:ffff:ffff:ffff:ffff:ffff
161feb2:a00::/28feb2:a0f:ffff:ffff:ffff:ffff:ffff:ffff
162feb2:a10::/28feb2:a1f:ffff:ffff:ffff:ffff:ffff:ffff
163feb2:a20::/28feb2:a2f:ffff:ffff:ffff:ffff:ffff:ffff
164feb2:a30::/28feb2:a3f:ffff:ffff:ffff:ffff:ffff:ffff
165feb2:a40::/28feb2:a4f:ffff:ffff:ffff:ffff:ffff:ffff
166feb2:a50::/28feb2:a5f:ffff:ffff:ffff:ffff:ffff:ffff
167feb2:a60::/28feb2:a6f:ffff:ffff:ffff:ffff:ffff:ffff
168feb2:a70::/28feb2:a7f:ffff:ffff:ffff:ffff:ffff:ffff
169feb2:a80::/28feb2:a8f:ffff:ffff:ffff:ffff:ffff:ffff
170feb2:a90::/28feb2:a9f:ffff:ffff:ffff:ffff:ffff:ffff
171feb2:aa0::/28feb2:aaf:ffff:ffff:ffff:ffff:ffff:ffff
172feb2:ab0::/28feb2:abf:ffff:ffff:ffff:ffff:ffff:ffff
173feb2:ac0::/28feb2:acf:ffff:ffff:ffff:ffff:ffff:ffff
174feb2:ad0::/28feb2:adf:ffff:ffff:ffff:ffff:ffff:ffff
175feb2:ae0::/28feb2:aef:ffff:ffff:ffff:ffff:ffff:ffff
176feb2:af0::/28feb2:aff:ffff:ffff:ffff:ffff:ffff:ffff
177feb2:b00::/28feb2:b0f:ffff:ffff:ffff:ffff:ffff:ffff
178feb2:b10::/28feb2:b1f:ffff:ffff:ffff:ffff:ffff:ffff
179feb2:b20::/28feb2:b2f:ffff:ffff:ffff:ffff:ffff:ffff
180feb2:b30::/28feb2:b3f:ffff:ffff:ffff:ffff:ffff:ffff
181feb2:b40::/28feb2:b4f:ffff:ffff:ffff:ffff:ffff:ffff
182feb2:b50::/28feb2:b5f:ffff:ffff:ffff:ffff:ffff:ffff
183feb2:b60::/28feb2:b6f:ffff:ffff:ffff:ffff:ffff:ffff
184feb2:b70::/28feb2:b7f:ffff:ffff:ffff:ffff:ffff:ffff
185feb2:b80::/28feb2:b8f:ffff:ffff:ffff:ffff:ffff:ffff
186feb2:b90::/28feb2:b9f:ffff:ffff:ffff:ffff:ffff:ffff
187feb2:ba0::/28feb2:baf:ffff:ffff:ffff:ffff:ffff:ffff
188feb2:bb0::/28feb2:bbf:ffff:ffff:ffff:ffff:ffff:ffff
189feb2:bc0::/28feb2:bcf:ffff:ffff:ffff:ffff:ffff:ffff
190feb2:bd0::/28feb2:bdf:ffff:ffff:ffff:ffff:ffff:ffff
191feb2:be0::/28feb2:bef:ffff:ffff:ffff:ffff:ffff:ffff
192feb2:bf0::/28feb2:bff:ffff:ffff:ffff:ffff:ffff:ffff
193feb2:c00::/28feb2:c0f:ffff:ffff:ffff:ffff:ffff:ffff
194feb2:c10::/28feb2:c1f:ffff:ffff:ffff:ffff:ffff:ffff
195feb2:c20::/28feb2:c2f:ffff:ffff:ffff:ffff:ffff:ffff
196feb2:c30::/28feb2:c3f:ffff:ffff:ffff:ffff:ffff:ffff
197feb2:c40::/28feb2:c4f:ffff:ffff:ffff:ffff:ffff:ffff
198feb2:c50::/28feb2:c5f:ffff:ffff:ffff:ffff:ffff:ffff
199feb2:c60::/28feb2:c6f:ffff:ffff:ffff:ffff:ffff:ffff
200feb2:c70::/28feb2:c7f:ffff:ffff:ffff:ffff:ffff:ffff
201feb2:c80::/28feb2:c8f:ffff:ffff:ffff:ffff:ffff:ffff
202feb2:c90::/28feb2:c9f:ffff:ffff:ffff:ffff:ffff:ffff
203feb2:ca0::/28feb2:caf:ffff:ffff:ffff:ffff:ffff:ffff
204feb2:cb0::/28feb2:cbf:ffff:ffff:ffff:ffff:ffff:ffff
205feb2:cc0::/28feb2:ccf:ffff:ffff:ffff:ffff:ffff:ffff
206feb2:cd0::/28feb2:cdf:ffff:ffff:ffff:ffff:ffff:ffff
207feb2:ce0::/28feb2:cef:ffff:ffff:ffff:ffff:ffff:ffff
208feb2:cf0::/28feb2:cff:ffff:ffff:ffff:ffff:ffff:ffff
209feb2:d00::/28feb2:d0f:ffff:ffff:ffff:ffff:ffff:ffff
210feb2:d10::/28feb2:d1f:ffff:ffff:ffff:ffff:ffff:ffff
211feb2:d20::/28feb2:d2f:ffff:ffff:ffff:ffff:ffff:ffff
212feb2:d30::/28feb2:d3f:ffff:ffff:ffff:ffff:ffff:ffff
213feb2:d40::/28feb2:d4f:ffff:ffff:ffff:ffff:ffff:ffff
214feb2:d50::/28feb2:d5f:ffff:ffff:ffff:ffff:ffff:ffff
215feb2:d60::/28feb2:d6f:ffff:ffff:ffff:ffff:ffff:ffff
216feb2:d70::/28feb2:d7f:ffff:ffff:ffff:ffff:ffff:ffff
217feb2:d80::/28feb2:d8f:ffff:ffff:ffff:ffff:ffff:ffff
218feb2:d90::/28feb2:d9f:ffff:ffff:ffff:ffff:ffff:ffff
219feb2:da0::/28feb2:daf:ffff:ffff:ffff:ffff:ffff:ffff
220feb2:db0::/28feb2:dbf:ffff:ffff:ffff:ffff:ffff:ffff
221feb2:dc0::/28feb2:dcf:ffff:ffff:ffff:ffff:ffff:ffff
222feb2:dd0::/28feb2:ddf:ffff:ffff:ffff:ffff:ffff:ffff
223feb2:de0::/28feb2:def:ffff:ffff:ffff:ffff:ffff:ffff
224feb2:df0::/28feb2:dff:ffff:ffff:ffff:ffff:ffff:ffff
225feb2:e00::/28feb2:e0f:ffff:ffff:ffff:ffff:ffff:ffff
226feb2:e10::/28feb2:e1f:ffff:ffff:ffff:ffff:ffff:ffff
227feb2:e20::/28feb2:e2f:ffff:ffff:ffff:ffff:ffff:ffff
228feb2:e30::/28feb2:e3f:ffff:ffff:ffff:ffff:ffff:ffff
229feb2:e40::/28feb2:e4f:ffff:ffff:ffff:ffff:ffff:ffff
230feb2:e50::/28feb2:e5f:ffff:ffff:ffff:ffff:ffff:ffff
231feb2:e60::/28feb2:e6f:ffff:ffff:ffff:ffff:ffff:ffff
232feb2:e70::/28feb2:e7f:ffff:ffff:ffff:ffff:ffff:ffff
233feb2:e80::/28feb2:e8f:ffff:ffff:ffff:ffff:ffff:ffff
234feb2:e90::/28feb2:e9f:ffff:ffff:ffff:ffff:ffff:ffff
235feb2:ea0::/28feb2:eaf:ffff:ffff:ffff:ffff:ffff:ffff
236feb2:eb0::/28feb2:ebf:ffff:ffff:ffff:ffff:ffff:ffff
237feb2:ec0::/28feb2:ecf:ffff:ffff:ffff:ffff:ffff:ffff
238feb2:ed0::/28feb2:edf:ffff:ffff:ffff:ffff:ffff:ffff
239feb2:ee0::/28feb2:eef:ffff:ffff:ffff:ffff:ffff:ffff
240feb2:ef0::/28feb2:eff:ffff:ffff:ffff:ffff:ffff:ffff
241feb2:f00::/28feb2:f0f:ffff:ffff:ffff:ffff:ffff:ffff
242feb2:f10::/28feb2:f1f:ffff:ffff:ffff:ffff:ffff:ffff
243feb2:f20::/28feb2:f2f:ffff:ffff:ffff:ffff:ffff:ffff
244feb2:f30::/28feb2:f3f:ffff:ffff:ffff:ffff:ffff:ffff
245feb2:f40::/28feb2:f4f:ffff:ffff:ffff:ffff:ffff:ffff
246feb2:f50::/28feb2:f5f:ffff:ffff:ffff:ffff:ffff:ffff
247feb2:f60::/28feb2:f6f:ffff:ffff:ffff:ffff:ffff:ffff
248feb2:f70::/28feb2:f7f:ffff:ffff:ffff:ffff:ffff:ffff
249feb2:f80::/28feb2:f8f:ffff:ffff:ffff:ffff:ffff:ffff
250feb2:f90::/28feb2:f9f:ffff:ffff:ffff:ffff:ffff:ffff
251feb2:fa0::/28feb2:faf:ffff:ffff:ffff:ffff:ffff:ffff
252feb2:fb0::/28feb2:fbf:ffff:ffff:ffff:ffff:ffff:ffff
253feb2:fc0::/28feb2:fcf:ffff:ffff:ffff:ffff:ffff:ffff
254feb2:fd0::/28feb2:fdf:ffff:ffff:ffff:ffff:ffff:ffff
255feb2:fe0::/28feb2:fef:ffff:ffff:ffff:ffff:ffff:ffff
256feb2:ff0::/28feb2: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.