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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
ffdc::/14
First address
ffdc::
Last address
ffdf: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
ffdc:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zones
c.d.f.f.ip6.arpa
d.d.f.f.ip6.arpa
e.d.f.f.ip6.arpa
f.d.f.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)

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

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