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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/15
Addresses2^113
/64 networks2^49
Network
fc6e::/15
First address
fc6e::
Last address
fc6f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
10,384,593,717,069,655,257,060,992,658,440,192 (2^113)
/64 networks (LANs)
562,949,953,421,312 (2^49)
Full form
fc6e:0000:0000:0000:0000:0000:0000:0000
Type
Unique local (ULA) fc00::/7
Private IPv6, like RFC 1918; usually fd00::/8
Reverse DNS zones
e.6.c.f.ip6.arpa
f.6.c.f.ip6.arpa
/15 is not on a 4-bit boundary, so it takes 2 /16 zones.
Split into smaller subnets/28
/16 (2)/17 (4)/18 (8)/19 (16)/20 (32)/24 (512)/28 (8,192)

fc6e::/15 makes 8,192 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
1fc6e::/28fc6e:f:ffff:ffff:ffff:ffff:ffff:ffff
2fc6e:10::/28fc6e:1f:ffff:ffff:ffff:ffff:ffff:ffff
3fc6e:20::/28fc6e:2f:ffff:ffff:ffff:ffff:ffff:ffff
4fc6e:30::/28fc6e:3f:ffff:ffff:ffff:ffff:ffff:ffff
5fc6e:40::/28fc6e:4f:ffff:ffff:ffff:ffff:ffff:ffff
6fc6e:50::/28fc6e:5f:ffff:ffff:ffff:ffff:ffff:ffff
7fc6e:60::/28fc6e:6f:ffff:ffff:ffff:ffff:ffff:ffff
8fc6e:70::/28fc6e:7f:ffff:ffff:ffff:ffff:ffff:ffff
9fc6e:80::/28fc6e:8f:ffff:ffff:ffff:ffff:ffff:ffff
10fc6e:90::/28fc6e:9f:ffff:ffff:ffff:ffff:ffff:ffff
11fc6e:a0::/28fc6e:af:ffff:ffff:ffff:ffff:ffff:ffff
12fc6e:b0::/28fc6e:bf:ffff:ffff:ffff:ffff:ffff:ffff
13fc6e:c0::/28fc6e:cf:ffff:ffff:ffff:ffff:ffff:ffff
14fc6e:d0::/28fc6e:df:ffff:ffff:ffff:ffff:ffff:ffff
15fc6e:e0::/28fc6e:ef:ffff:ffff:ffff:ffff:ffff:ffff
16fc6e:f0::/28fc6e:ff:ffff:ffff:ffff:ffff:ffff:ffff
17fc6e:100::/28fc6e:10f:ffff:ffff:ffff:ffff:ffff:ffff
18fc6e:110::/28fc6e:11f:ffff:ffff:ffff:ffff:ffff:ffff
19fc6e:120::/28fc6e:12f:ffff:ffff:ffff:ffff:ffff:ffff
20fc6e:130::/28fc6e:13f:ffff:ffff:ffff:ffff:ffff:ffff
21fc6e:140::/28fc6e:14f:ffff:ffff:ffff:ffff:ffff:ffff
22fc6e:150::/28fc6e:15f:ffff:ffff:ffff:ffff:ffff:ffff
23fc6e:160::/28fc6e:16f:ffff:ffff:ffff:ffff:ffff:ffff
24fc6e:170::/28fc6e:17f:ffff:ffff:ffff:ffff:ffff:ffff
25fc6e:180::/28fc6e:18f:ffff:ffff:ffff:ffff:ffff:ffff
26fc6e:190::/28fc6e:19f:ffff:ffff:ffff:ffff:ffff:ffff
27fc6e:1a0::/28fc6e:1af:ffff:ffff:ffff:ffff:ffff:ffff
28fc6e:1b0::/28fc6e:1bf:ffff:ffff:ffff:ffff:ffff:ffff
29fc6e:1c0::/28fc6e:1cf:ffff:ffff:ffff:ffff:ffff:ffff
30fc6e:1d0::/28fc6e:1df:ffff:ffff:ffff:ffff:ffff:ffff
31fc6e:1e0::/28fc6e:1ef:ffff:ffff:ffff:ffff:ffff:ffff
32fc6e:1f0::/28fc6e:1ff:ffff:ffff:ffff:ffff:ffff:ffff
33fc6e:200::/28fc6e:20f:ffff:ffff:ffff:ffff:ffff:ffff
34fc6e:210::/28fc6e:21f:ffff:ffff:ffff:ffff:ffff:ffff
35fc6e:220::/28fc6e:22f:ffff:ffff:ffff:ffff:ffff:ffff
36fc6e:230::/28fc6e:23f:ffff:ffff:ffff:ffff:ffff:ffff
37fc6e:240::/28fc6e:24f:ffff:ffff:ffff:ffff:ffff:ffff
38fc6e:250::/28fc6e:25f:ffff:ffff:ffff:ffff:ffff:ffff
39fc6e:260::/28fc6e:26f:ffff:ffff:ffff:ffff:ffff:ffff
40fc6e:270::/28fc6e:27f:ffff:ffff:ffff:ffff:ffff:ffff
41fc6e:280::/28fc6e:28f:ffff:ffff:ffff:ffff:ffff:ffff
42fc6e:290::/28fc6e:29f:ffff:ffff:ffff:ffff:ffff:ffff
43fc6e:2a0::/28fc6e:2af:ffff:ffff:ffff:ffff:ffff:ffff
44fc6e:2b0::/28fc6e:2bf:ffff:ffff:ffff:ffff:ffff:ffff
45fc6e:2c0::/28fc6e:2cf:ffff:ffff:ffff:ffff:ffff:ffff
46fc6e:2d0::/28fc6e:2df:ffff:ffff:ffff:ffff:ffff:ffff
47fc6e:2e0::/28fc6e:2ef:ffff:ffff:ffff:ffff:ffff:ffff
48fc6e:2f0::/28fc6e:2ff:ffff:ffff:ffff:ffff:ffff:ffff
49fc6e:300::/28fc6e:30f:ffff:ffff:ffff:ffff:ffff:ffff
50fc6e:310::/28fc6e:31f:ffff:ffff:ffff:ffff:ffff:ffff
51fc6e:320::/28fc6e:32f:ffff:ffff:ffff:ffff:ffff:ffff
52fc6e:330::/28fc6e:33f:ffff:ffff:ffff:ffff:ffff:ffff
53fc6e:340::/28fc6e:34f:ffff:ffff:ffff:ffff:ffff:ffff
54fc6e:350::/28fc6e:35f:ffff:ffff:ffff:ffff:ffff:ffff
55fc6e:360::/28fc6e:36f:ffff:ffff:ffff:ffff:ffff:ffff
56fc6e:370::/28fc6e:37f:ffff:ffff:ffff:ffff:ffff:ffff
57fc6e:380::/28fc6e:38f:ffff:ffff:ffff:ffff:ffff:ffff
58fc6e:390::/28fc6e:39f:ffff:ffff:ffff:ffff:ffff:ffff
59fc6e:3a0::/28fc6e:3af:ffff:ffff:ffff:ffff:ffff:ffff
60fc6e:3b0::/28fc6e:3bf:ffff:ffff:ffff:ffff:ffff:ffff
61fc6e:3c0::/28fc6e:3cf:ffff:ffff:ffff:ffff:ffff:ffff
62fc6e:3d0::/28fc6e:3df:ffff:ffff:ffff:ffff:ffff:ffff
63fc6e:3e0::/28fc6e:3ef:ffff:ffff:ffff:ffff:ffff:ffff
64fc6e:3f0::/28fc6e:3ff:ffff:ffff:ffff:ffff:ffff:ffff
65fc6e:400::/28fc6e:40f:ffff:ffff:ffff:ffff:ffff:ffff
66fc6e:410::/28fc6e:41f:ffff:ffff:ffff:ffff:ffff:ffff
67fc6e:420::/28fc6e:42f:ffff:ffff:ffff:ffff:ffff:ffff
68fc6e:430::/28fc6e:43f:ffff:ffff:ffff:ffff:ffff:ffff
69fc6e:440::/28fc6e:44f:ffff:ffff:ffff:ffff:ffff:ffff
70fc6e:450::/28fc6e:45f:ffff:ffff:ffff:ffff:ffff:ffff
71fc6e:460::/28fc6e:46f:ffff:ffff:ffff:ffff:ffff:ffff
72fc6e:470::/28fc6e:47f:ffff:ffff:ffff:ffff:ffff:ffff
73fc6e:480::/28fc6e:48f:ffff:ffff:ffff:ffff:ffff:ffff
74fc6e:490::/28fc6e:49f:ffff:ffff:ffff:ffff:ffff:ffff
75fc6e:4a0::/28fc6e:4af:ffff:ffff:ffff:ffff:ffff:ffff
76fc6e:4b0::/28fc6e:4bf:ffff:ffff:ffff:ffff:ffff:ffff
77fc6e:4c0::/28fc6e:4cf:ffff:ffff:ffff:ffff:ffff:ffff
78fc6e:4d0::/28fc6e:4df:ffff:ffff:ffff:ffff:ffff:ffff
79fc6e:4e0::/28fc6e:4ef:ffff:ffff:ffff:ffff:ffff:ffff
80fc6e:4f0::/28fc6e:4ff:ffff:ffff:ffff:ffff:ffff:ffff
81fc6e:500::/28fc6e:50f:ffff:ffff:ffff:ffff:ffff:ffff
82fc6e:510::/28fc6e:51f:ffff:ffff:ffff:ffff:ffff:ffff
83fc6e:520::/28fc6e:52f:ffff:ffff:ffff:ffff:ffff:ffff
84fc6e:530::/28fc6e:53f:ffff:ffff:ffff:ffff:ffff:ffff
85fc6e:540::/28fc6e:54f:ffff:ffff:ffff:ffff:ffff:ffff
86fc6e:550::/28fc6e:55f:ffff:ffff:ffff:ffff:ffff:ffff
87fc6e:560::/28fc6e:56f:ffff:ffff:ffff:ffff:ffff:ffff
88fc6e:570::/28fc6e:57f:ffff:ffff:ffff:ffff:ffff:ffff
89fc6e:580::/28fc6e:58f:ffff:ffff:ffff:ffff:ffff:ffff
90fc6e:590::/28fc6e:59f:ffff:ffff:ffff:ffff:ffff:ffff
91fc6e:5a0::/28fc6e:5af:ffff:ffff:ffff:ffff:ffff:ffff
92fc6e:5b0::/28fc6e:5bf:ffff:ffff:ffff:ffff:ffff:ffff
93fc6e:5c0::/28fc6e:5cf:ffff:ffff:ffff:ffff:ffff:ffff
94fc6e:5d0::/28fc6e:5df:ffff:ffff:ffff:ffff:ffff:ffff
95fc6e:5e0::/28fc6e:5ef:ffff:ffff:ffff:ffff:ffff:ffff
96fc6e:5f0::/28fc6e:5ff:ffff:ffff:ffff:ffff:ffff:ffff
97fc6e:600::/28fc6e:60f:ffff:ffff:ffff:ffff:ffff:ffff
98fc6e:610::/28fc6e:61f:ffff:ffff:ffff:ffff:ffff:ffff
99fc6e:620::/28fc6e:62f:ffff:ffff:ffff:ffff:ffff:ffff
100fc6e:630::/28fc6e:63f:ffff:ffff:ffff:ffff:ffff:ffff
101fc6e:640::/28fc6e:64f:ffff:ffff:ffff:ffff:ffff:ffff
102fc6e:650::/28fc6e:65f:ffff:ffff:ffff:ffff:ffff:ffff
103fc6e:660::/28fc6e:66f:ffff:ffff:ffff:ffff:ffff:ffff
104fc6e:670::/28fc6e:67f:ffff:ffff:ffff:ffff:ffff:ffff
105fc6e:680::/28fc6e:68f:ffff:ffff:ffff:ffff:ffff:ffff
106fc6e:690::/28fc6e:69f:ffff:ffff:ffff:ffff:ffff:ffff
107fc6e:6a0::/28fc6e:6af:ffff:ffff:ffff:ffff:ffff:ffff
108fc6e:6b0::/28fc6e:6bf:ffff:ffff:ffff:ffff:ffff:ffff
109fc6e:6c0::/28fc6e:6cf:ffff:ffff:ffff:ffff:ffff:ffff
110fc6e:6d0::/28fc6e:6df:ffff:ffff:ffff:ffff:ffff:ffff
111fc6e:6e0::/28fc6e:6ef:ffff:ffff:ffff:ffff:ffff:ffff
112fc6e:6f0::/28fc6e:6ff:ffff:ffff:ffff:ffff:ffff:ffff
113fc6e:700::/28fc6e:70f:ffff:ffff:ffff:ffff:ffff:ffff
114fc6e:710::/28fc6e:71f:ffff:ffff:ffff:ffff:ffff:ffff
115fc6e:720::/28fc6e:72f:ffff:ffff:ffff:ffff:ffff:ffff
116fc6e:730::/28fc6e:73f:ffff:ffff:ffff:ffff:ffff:ffff
117fc6e:740::/28fc6e:74f:ffff:ffff:ffff:ffff:ffff:ffff
118fc6e:750::/28fc6e:75f:ffff:ffff:ffff:ffff:ffff:ffff
119fc6e:760::/28fc6e:76f:ffff:ffff:ffff:ffff:ffff:ffff
120fc6e:770::/28fc6e:77f:ffff:ffff:ffff:ffff:ffff:ffff
121fc6e:780::/28fc6e:78f:ffff:ffff:ffff:ffff:ffff:ffff
122fc6e:790::/28fc6e:79f:ffff:ffff:ffff:ffff:ffff:ffff
123fc6e:7a0::/28fc6e:7af:ffff:ffff:ffff:ffff:ffff:ffff
124fc6e:7b0::/28fc6e:7bf:ffff:ffff:ffff:ffff:ffff:ffff
125fc6e:7c0::/28fc6e:7cf:ffff:ffff:ffff:ffff:ffff:ffff
126fc6e:7d0::/28fc6e:7df:ffff:ffff:ffff:ffff:ffff:ffff
127fc6e:7e0::/28fc6e:7ef:ffff:ffff:ffff:ffff:ffff:ffff
128fc6e:7f0::/28fc6e:7ff:ffff:ffff:ffff:ffff:ffff:ffff
129fc6e:800::/28fc6e:80f:ffff:ffff:ffff:ffff:ffff:ffff
130fc6e:810::/28fc6e:81f:ffff:ffff:ffff:ffff:ffff:ffff
131fc6e:820::/28fc6e:82f:ffff:ffff:ffff:ffff:ffff:ffff
132fc6e:830::/28fc6e:83f:ffff:ffff:ffff:ffff:ffff:ffff
133fc6e:840::/28fc6e:84f:ffff:ffff:ffff:ffff:ffff:ffff
134fc6e:850::/28fc6e:85f:ffff:ffff:ffff:ffff:ffff:ffff
135fc6e:860::/28fc6e:86f:ffff:ffff:ffff:ffff:ffff:ffff
136fc6e:870::/28fc6e:87f:ffff:ffff:ffff:ffff:ffff:ffff
137fc6e:880::/28fc6e:88f:ffff:ffff:ffff:ffff:ffff:ffff
138fc6e:890::/28fc6e:89f:ffff:ffff:ffff:ffff:ffff:ffff
139fc6e:8a0::/28fc6e:8af:ffff:ffff:ffff:ffff:ffff:ffff
140fc6e:8b0::/28fc6e:8bf:ffff:ffff:ffff:ffff:ffff:ffff
141fc6e:8c0::/28fc6e:8cf:ffff:ffff:ffff:ffff:ffff:ffff
142fc6e:8d0::/28fc6e:8df:ffff:ffff:ffff:ffff:ffff:ffff
143fc6e:8e0::/28fc6e:8ef:ffff:ffff:ffff:ffff:ffff:ffff
144fc6e:8f0::/28fc6e:8ff:ffff:ffff:ffff:ffff:ffff:ffff
145fc6e:900::/28fc6e:90f:ffff:ffff:ffff:ffff:ffff:ffff
146fc6e:910::/28fc6e:91f:ffff:ffff:ffff:ffff:ffff:ffff
147fc6e:920::/28fc6e:92f:ffff:ffff:ffff:ffff:ffff:ffff
148fc6e:930::/28fc6e:93f:ffff:ffff:ffff:ffff:ffff:ffff
149fc6e:940::/28fc6e:94f:ffff:ffff:ffff:ffff:ffff:ffff
150fc6e:950::/28fc6e:95f:ffff:ffff:ffff:ffff:ffff:ffff
151fc6e:960::/28fc6e:96f:ffff:ffff:ffff:ffff:ffff:ffff
152fc6e:970::/28fc6e:97f:ffff:ffff:ffff:ffff:ffff:ffff
153fc6e:980::/28fc6e:98f:ffff:ffff:ffff:ffff:ffff:ffff
154fc6e:990::/28fc6e:99f:ffff:ffff:ffff:ffff:ffff:ffff
155fc6e:9a0::/28fc6e:9af:ffff:ffff:ffff:ffff:ffff:ffff
156fc6e:9b0::/28fc6e:9bf:ffff:ffff:ffff:ffff:ffff:ffff
157fc6e:9c0::/28fc6e:9cf:ffff:ffff:ffff:ffff:ffff:ffff
158fc6e:9d0::/28fc6e:9df:ffff:ffff:ffff:ffff:ffff:ffff
159fc6e:9e0::/28fc6e:9ef:ffff:ffff:ffff:ffff:ffff:ffff
160fc6e:9f0::/28fc6e:9ff:ffff:ffff:ffff:ffff:ffff:ffff
161fc6e:a00::/28fc6e:a0f:ffff:ffff:ffff:ffff:ffff:ffff
162fc6e:a10::/28fc6e:a1f:ffff:ffff:ffff:ffff:ffff:ffff
163fc6e:a20::/28fc6e:a2f:ffff:ffff:ffff:ffff:ffff:ffff
164fc6e:a30::/28fc6e:a3f:ffff:ffff:ffff:ffff:ffff:ffff
165fc6e:a40::/28fc6e:a4f:ffff:ffff:ffff:ffff:ffff:ffff
166fc6e:a50::/28fc6e:a5f:ffff:ffff:ffff:ffff:ffff:ffff
167fc6e:a60::/28fc6e:a6f:ffff:ffff:ffff:ffff:ffff:ffff
168fc6e:a70::/28fc6e:a7f:ffff:ffff:ffff:ffff:ffff:ffff
169fc6e:a80::/28fc6e:a8f:ffff:ffff:ffff:ffff:ffff:ffff
170fc6e:a90::/28fc6e:a9f:ffff:ffff:ffff:ffff:ffff:ffff
171fc6e:aa0::/28fc6e:aaf:ffff:ffff:ffff:ffff:ffff:ffff
172fc6e:ab0::/28fc6e:abf:ffff:ffff:ffff:ffff:ffff:ffff
173fc6e:ac0::/28fc6e:acf:ffff:ffff:ffff:ffff:ffff:ffff
174fc6e:ad0::/28fc6e:adf:ffff:ffff:ffff:ffff:ffff:ffff
175fc6e:ae0::/28fc6e:aef:ffff:ffff:ffff:ffff:ffff:ffff
176fc6e:af0::/28fc6e:aff:ffff:ffff:ffff:ffff:ffff:ffff
177fc6e:b00::/28fc6e:b0f:ffff:ffff:ffff:ffff:ffff:ffff
178fc6e:b10::/28fc6e:b1f:ffff:ffff:ffff:ffff:ffff:ffff
179fc6e:b20::/28fc6e:b2f:ffff:ffff:ffff:ffff:ffff:ffff
180fc6e:b30::/28fc6e:b3f:ffff:ffff:ffff:ffff:ffff:ffff
181fc6e:b40::/28fc6e:b4f:ffff:ffff:ffff:ffff:ffff:ffff
182fc6e:b50::/28fc6e:b5f:ffff:ffff:ffff:ffff:ffff:ffff
183fc6e:b60::/28fc6e:b6f:ffff:ffff:ffff:ffff:ffff:ffff
184fc6e:b70::/28fc6e:b7f:ffff:ffff:ffff:ffff:ffff:ffff
185fc6e:b80::/28fc6e:b8f:ffff:ffff:ffff:ffff:ffff:ffff
186fc6e:b90::/28fc6e:b9f:ffff:ffff:ffff:ffff:ffff:ffff
187fc6e:ba0::/28fc6e:baf:ffff:ffff:ffff:ffff:ffff:ffff
188fc6e:bb0::/28fc6e:bbf:ffff:ffff:ffff:ffff:ffff:ffff
189fc6e:bc0::/28fc6e:bcf:ffff:ffff:ffff:ffff:ffff:ffff
190fc6e:bd0::/28fc6e:bdf:ffff:ffff:ffff:ffff:ffff:ffff
191fc6e:be0::/28fc6e:bef:ffff:ffff:ffff:ffff:ffff:ffff
192fc6e:bf0::/28fc6e:bff:ffff:ffff:ffff:ffff:ffff:ffff
193fc6e:c00::/28fc6e:c0f:ffff:ffff:ffff:ffff:ffff:ffff
194fc6e:c10::/28fc6e:c1f:ffff:ffff:ffff:ffff:ffff:ffff
195fc6e:c20::/28fc6e:c2f:ffff:ffff:ffff:ffff:ffff:ffff
196fc6e:c30::/28fc6e:c3f:ffff:ffff:ffff:ffff:ffff:ffff
197fc6e:c40::/28fc6e:c4f:ffff:ffff:ffff:ffff:ffff:ffff
198fc6e:c50::/28fc6e:c5f:ffff:ffff:ffff:ffff:ffff:ffff
199fc6e:c60::/28fc6e:c6f:ffff:ffff:ffff:ffff:ffff:ffff
200fc6e:c70::/28fc6e:c7f:ffff:ffff:ffff:ffff:ffff:ffff
201fc6e:c80::/28fc6e:c8f:ffff:ffff:ffff:ffff:ffff:ffff
202fc6e:c90::/28fc6e:c9f:ffff:ffff:ffff:ffff:ffff:ffff
203fc6e:ca0::/28fc6e:caf:ffff:ffff:ffff:ffff:ffff:ffff
204fc6e:cb0::/28fc6e:cbf:ffff:ffff:ffff:ffff:ffff:ffff
205fc6e:cc0::/28fc6e:ccf:ffff:ffff:ffff:ffff:ffff:ffff
206fc6e:cd0::/28fc6e:cdf:ffff:ffff:ffff:ffff:ffff:ffff
207fc6e:ce0::/28fc6e:cef:ffff:ffff:ffff:ffff:ffff:ffff
208fc6e:cf0::/28fc6e:cff:ffff:ffff:ffff:ffff:ffff:ffff
209fc6e:d00::/28fc6e:d0f:ffff:ffff:ffff:ffff:ffff:ffff
210fc6e:d10::/28fc6e:d1f:ffff:ffff:ffff:ffff:ffff:ffff
211fc6e:d20::/28fc6e:d2f:ffff:ffff:ffff:ffff:ffff:ffff
212fc6e:d30::/28fc6e:d3f:ffff:ffff:ffff:ffff:ffff:ffff
213fc6e:d40::/28fc6e:d4f:ffff:ffff:ffff:ffff:ffff:ffff
214fc6e:d50::/28fc6e:d5f:ffff:ffff:ffff:ffff:ffff:ffff
215fc6e:d60::/28fc6e:d6f:ffff:ffff:ffff:ffff:ffff:ffff
216fc6e:d70::/28fc6e:d7f:ffff:ffff:ffff:ffff:ffff:ffff
217fc6e:d80::/28fc6e:d8f:ffff:ffff:ffff:ffff:ffff:ffff
218fc6e:d90::/28fc6e:d9f:ffff:ffff:ffff:ffff:ffff:ffff
219fc6e:da0::/28fc6e:daf:ffff:ffff:ffff:ffff:ffff:ffff
220fc6e:db0::/28fc6e:dbf:ffff:ffff:ffff:ffff:ffff:ffff
221fc6e:dc0::/28fc6e:dcf:ffff:ffff:ffff:ffff:ffff:ffff
222fc6e:dd0::/28fc6e:ddf:ffff:ffff:ffff:ffff:ffff:ffff
223fc6e:de0::/28fc6e:def:ffff:ffff:ffff:ffff:ffff:ffff
224fc6e:df0::/28fc6e:dff:ffff:ffff:ffff:ffff:ffff:ffff
225fc6e:e00::/28fc6e:e0f:ffff:ffff:ffff:ffff:ffff:ffff
226fc6e:e10::/28fc6e:e1f:ffff:ffff:ffff:ffff:ffff:ffff
227fc6e:e20::/28fc6e:e2f:ffff:ffff:ffff:ffff:ffff:ffff
228fc6e:e30::/28fc6e:e3f:ffff:ffff:ffff:ffff:ffff:ffff
229fc6e:e40::/28fc6e:e4f:ffff:ffff:ffff:ffff:ffff:ffff
230fc6e:e50::/28fc6e:e5f:ffff:ffff:ffff:ffff:ffff:ffff
231fc6e:e60::/28fc6e:e6f:ffff:ffff:ffff:ffff:ffff:ffff
232fc6e:e70::/28fc6e:e7f:ffff:ffff:ffff:ffff:ffff:ffff
233fc6e:e80::/28fc6e:e8f:ffff:ffff:ffff:ffff:ffff:ffff
234fc6e:e90::/28fc6e:e9f:ffff:ffff:ffff:ffff:ffff:ffff
235fc6e:ea0::/28fc6e:eaf:ffff:ffff:ffff:ffff:ffff:ffff
236fc6e:eb0::/28fc6e:ebf:ffff:ffff:ffff:ffff:ffff:ffff
237fc6e:ec0::/28fc6e:ecf:ffff:ffff:ffff:ffff:ffff:ffff
238fc6e:ed0::/28fc6e:edf:ffff:ffff:ffff:ffff:ffff:ffff
239fc6e:ee0::/28fc6e:eef:ffff:ffff:ffff:ffff:ffff:ffff
240fc6e:ef0::/28fc6e:eff:ffff:ffff:ffff:ffff:ffff:ffff
241fc6e:f00::/28fc6e:f0f:ffff:ffff:ffff:ffff:ffff:ffff
242fc6e:f10::/28fc6e:f1f:ffff:ffff:ffff:ffff:ffff:ffff
243fc6e:f20::/28fc6e:f2f:ffff:ffff:ffff:ffff:ffff:ffff
244fc6e:f30::/28fc6e:f3f:ffff:ffff:ffff:ffff:ffff:ffff
245fc6e:f40::/28fc6e:f4f:ffff:ffff:ffff:ffff:ffff:ffff
246fc6e:f50::/28fc6e:f5f:ffff:ffff:ffff:ffff:ffff:ffff
247fc6e:f60::/28fc6e:f6f:ffff:ffff:ffff:ffff:ffff:ffff
248fc6e:f70::/28fc6e:f7f:ffff:ffff:ffff:ffff:ffff:ffff
249fc6e:f80::/28fc6e:f8f:ffff:ffff:ffff:ffff:ffff:ffff
250fc6e:f90::/28fc6e:f9f:ffff:ffff:ffff:ffff:ffff:ffff
251fc6e:fa0::/28fc6e:faf:ffff:ffff:ffff:ffff:ffff:ffff
252fc6e:fb0::/28fc6e:fbf:ffff:ffff:ffff:ffff:ffff:ffff
253fc6e:fc0::/28fc6e:fcf:ffff:ffff:ffff:ffff:ffff:ffff
254fc6e:fd0::/28fc6e:fdf:ffff:ffff:ffff:ffff:ffff:ffff
255fc6e:fe0::/28fc6e:fef:ffff:ffff:ffff:ffff:ffff:ffff
256fc6e:ff0::/28fc6e: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.