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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/14
Addresses2^114
/64 networks2^50
Network
feac::/14
First address
feac::
Last address
feaf:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
20,769,187,434,139,310,514,121,985,316,880,384 (2^114)
/64 networks (LANs)
1,125,899,906,842,624 (2^50)
Full form
feac:0000:0000:0000:0000:0000:0000:0000
Type
Link-local fe80::/10
Every IPv6 interface has one; not routed
Reverse DNS zones
c.a.e.f.ip6.arpa
d.a.e.f.ip6.arpa
e.a.e.f.ip6.arpa
f.a.e.f.ip6.arpa
/14 is not on a 4-bit boundary, so it takes 4 /16 zones.
Split into smaller subnets/28
/15 (2)/16 (4)/17 (8)/18 (16)/20 (64)/24 (1,024)/28 (16,384)

feac::/14 makes 16,384 subnets of /28; the first 256 are listed.

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