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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
fc46::/16
First address
fc46::
Last address
fc46: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
fc46:0000:0000:0000:0000:0000:0000:0000
Type
Unique local (ULA) fc00::/7
Private IPv6, like RFC 1918; usually fd00::/8
Reverse DNS zone
6.4.c.f.ip6.arpa
Split into smaller subnets/28
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

fc46::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
1fc46::/28fc46:f:ffff:ffff:ffff:ffff:ffff:ffff
2fc46:10::/28fc46:1f:ffff:ffff:ffff:ffff:ffff:ffff
3fc46:20::/28fc46:2f:ffff:ffff:ffff:ffff:ffff:ffff
4fc46:30::/28fc46:3f:ffff:ffff:ffff:ffff:ffff:ffff
5fc46:40::/28fc46:4f:ffff:ffff:ffff:ffff:ffff:ffff
6fc46:50::/28fc46:5f:ffff:ffff:ffff:ffff:ffff:ffff
7fc46:60::/28fc46:6f:ffff:ffff:ffff:ffff:ffff:ffff
8fc46:70::/28fc46:7f:ffff:ffff:ffff:ffff:ffff:ffff
9fc46:80::/28fc46:8f:ffff:ffff:ffff:ffff:ffff:ffff
10fc46:90::/28fc46:9f:ffff:ffff:ffff:ffff:ffff:ffff
11fc46:a0::/28fc46:af:ffff:ffff:ffff:ffff:ffff:ffff
12fc46:b0::/28fc46:bf:ffff:ffff:ffff:ffff:ffff:ffff
13fc46:c0::/28fc46:cf:ffff:ffff:ffff:ffff:ffff:ffff
14fc46:d0::/28fc46:df:ffff:ffff:ffff:ffff:ffff:ffff
15fc46:e0::/28fc46:ef:ffff:ffff:ffff:ffff:ffff:ffff
16fc46:f0::/28fc46:ff:ffff:ffff:ffff:ffff:ffff:ffff
17fc46:100::/28fc46:10f:ffff:ffff:ffff:ffff:ffff:ffff
18fc46:110::/28fc46:11f:ffff:ffff:ffff:ffff:ffff:ffff
19fc46:120::/28fc46:12f:ffff:ffff:ffff:ffff:ffff:ffff
20fc46:130::/28fc46:13f:ffff:ffff:ffff:ffff:ffff:ffff
21fc46:140::/28fc46:14f:ffff:ffff:ffff:ffff:ffff:ffff
22fc46:150::/28fc46:15f:ffff:ffff:ffff:ffff:ffff:ffff
23fc46:160::/28fc46:16f:ffff:ffff:ffff:ffff:ffff:ffff
24fc46:170::/28fc46:17f:ffff:ffff:ffff:ffff:ffff:ffff
25fc46:180::/28fc46:18f:ffff:ffff:ffff:ffff:ffff:ffff
26fc46:190::/28fc46:19f:ffff:ffff:ffff:ffff:ffff:ffff
27fc46:1a0::/28fc46:1af:ffff:ffff:ffff:ffff:ffff:ffff
28fc46:1b0::/28fc46:1bf:ffff:ffff:ffff:ffff:ffff:ffff
29fc46:1c0::/28fc46:1cf:ffff:ffff:ffff:ffff:ffff:ffff
30fc46:1d0::/28fc46:1df:ffff:ffff:ffff:ffff:ffff:ffff
31fc46:1e0::/28fc46:1ef:ffff:ffff:ffff:ffff:ffff:ffff
32fc46:1f0::/28fc46:1ff:ffff:ffff:ffff:ffff:ffff:ffff
33fc46:200::/28fc46:20f:ffff:ffff:ffff:ffff:ffff:ffff
34fc46:210::/28fc46:21f:ffff:ffff:ffff:ffff:ffff:ffff
35fc46:220::/28fc46:22f:ffff:ffff:ffff:ffff:ffff:ffff
36fc46:230::/28fc46:23f:ffff:ffff:ffff:ffff:ffff:ffff
37fc46:240::/28fc46:24f:ffff:ffff:ffff:ffff:ffff:ffff
38fc46:250::/28fc46:25f:ffff:ffff:ffff:ffff:ffff:ffff
39fc46:260::/28fc46:26f:ffff:ffff:ffff:ffff:ffff:ffff
40fc46:270::/28fc46:27f:ffff:ffff:ffff:ffff:ffff:ffff
41fc46:280::/28fc46:28f:ffff:ffff:ffff:ffff:ffff:ffff
42fc46:290::/28fc46:29f:ffff:ffff:ffff:ffff:ffff:ffff
43fc46:2a0::/28fc46:2af:ffff:ffff:ffff:ffff:ffff:ffff
44fc46:2b0::/28fc46:2bf:ffff:ffff:ffff:ffff:ffff:ffff
45fc46:2c0::/28fc46:2cf:ffff:ffff:ffff:ffff:ffff:ffff
46fc46:2d0::/28fc46:2df:ffff:ffff:ffff:ffff:ffff:ffff
47fc46:2e0::/28fc46:2ef:ffff:ffff:ffff:ffff:ffff:ffff
48fc46:2f0::/28fc46:2ff:ffff:ffff:ffff:ffff:ffff:ffff
49fc46:300::/28fc46:30f:ffff:ffff:ffff:ffff:ffff:ffff
50fc46:310::/28fc46:31f:ffff:ffff:ffff:ffff:ffff:ffff
51fc46:320::/28fc46:32f:ffff:ffff:ffff:ffff:ffff:ffff
52fc46:330::/28fc46:33f:ffff:ffff:ffff:ffff:ffff:ffff
53fc46:340::/28fc46:34f:ffff:ffff:ffff:ffff:ffff:ffff
54fc46:350::/28fc46:35f:ffff:ffff:ffff:ffff:ffff:ffff
55fc46:360::/28fc46:36f:ffff:ffff:ffff:ffff:ffff:ffff
56fc46:370::/28fc46:37f:ffff:ffff:ffff:ffff:ffff:ffff
57fc46:380::/28fc46:38f:ffff:ffff:ffff:ffff:ffff:ffff
58fc46:390::/28fc46:39f:ffff:ffff:ffff:ffff:ffff:ffff
59fc46:3a0::/28fc46:3af:ffff:ffff:ffff:ffff:ffff:ffff
60fc46:3b0::/28fc46:3bf:ffff:ffff:ffff:ffff:ffff:ffff
61fc46:3c0::/28fc46:3cf:ffff:ffff:ffff:ffff:ffff:ffff
62fc46:3d0::/28fc46:3df:ffff:ffff:ffff:ffff:ffff:ffff
63fc46:3e0::/28fc46:3ef:ffff:ffff:ffff:ffff:ffff:ffff
64fc46:3f0::/28fc46:3ff:ffff:ffff:ffff:ffff:ffff:ffff
65fc46:400::/28fc46:40f:ffff:ffff:ffff:ffff:ffff:ffff
66fc46:410::/28fc46:41f:ffff:ffff:ffff:ffff:ffff:ffff
67fc46:420::/28fc46:42f:ffff:ffff:ffff:ffff:ffff:ffff
68fc46:430::/28fc46:43f:ffff:ffff:ffff:ffff:ffff:ffff
69fc46:440::/28fc46:44f:ffff:ffff:ffff:ffff:ffff:ffff
70fc46:450::/28fc46:45f:ffff:ffff:ffff:ffff:ffff:ffff
71fc46:460::/28fc46:46f:ffff:ffff:ffff:ffff:ffff:ffff
72fc46:470::/28fc46:47f:ffff:ffff:ffff:ffff:ffff:ffff
73fc46:480::/28fc46:48f:ffff:ffff:ffff:ffff:ffff:ffff
74fc46:490::/28fc46:49f:ffff:ffff:ffff:ffff:ffff:ffff
75fc46:4a0::/28fc46:4af:ffff:ffff:ffff:ffff:ffff:ffff
76fc46:4b0::/28fc46:4bf:ffff:ffff:ffff:ffff:ffff:ffff
77fc46:4c0::/28fc46:4cf:ffff:ffff:ffff:ffff:ffff:ffff
78fc46:4d0::/28fc46:4df:ffff:ffff:ffff:ffff:ffff:ffff
79fc46:4e0::/28fc46:4ef:ffff:ffff:ffff:ffff:ffff:ffff
80fc46:4f0::/28fc46:4ff:ffff:ffff:ffff:ffff:ffff:ffff
81fc46:500::/28fc46:50f:ffff:ffff:ffff:ffff:ffff:ffff
82fc46:510::/28fc46:51f:ffff:ffff:ffff:ffff:ffff:ffff
83fc46:520::/28fc46:52f:ffff:ffff:ffff:ffff:ffff:ffff
84fc46:530::/28fc46:53f:ffff:ffff:ffff:ffff:ffff:ffff
85fc46:540::/28fc46:54f:ffff:ffff:ffff:ffff:ffff:ffff
86fc46:550::/28fc46:55f:ffff:ffff:ffff:ffff:ffff:ffff
87fc46:560::/28fc46:56f:ffff:ffff:ffff:ffff:ffff:ffff
88fc46:570::/28fc46:57f:ffff:ffff:ffff:ffff:ffff:ffff
89fc46:580::/28fc46:58f:ffff:ffff:ffff:ffff:ffff:ffff
90fc46:590::/28fc46:59f:ffff:ffff:ffff:ffff:ffff:ffff
91fc46:5a0::/28fc46:5af:ffff:ffff:ffff:ffff:ffff:ffff
92fc46:5b0::/28fc46:5bf:ffff:ffff:ffff:ffff:ffff:ffff
93fc46:5c0::/28fc46:5cf:ffff:ffff:ffff:ffff:ffff:ffff
94fc46:5d0::/28fc46:5df:ffff:ffff:ffff:ffff:ffff:ffff
95fc46:5e0::/28fc46:5ef:ffff:ffff:ffff:ffff:ffff:ffff
96fc46:5f0::/28fc46:5ff:ffff:ffff:ffff:ffff:ffff:ffff
97fc46:600::/28fc46:60f:ffff:ffff:ffff:ffff:ffff:ffff
98fc46:610::/28fc46:61f:ffff:ffff:ffff:ffff:ffff:ffff
99fc46:620::/28fc46:62f:ffff:ffff:ffff:ffff:ffff:ffff
100fc46:630::/28fc46:63f:ffff:ffff:ffff:ffff:ffff:ffff
101fc46:640::/28fc46:64f:ffff:ffff:ffff:ffff:ffff:ffff
102fc46:650::/28fc46:65f:ffff:ffff:ffff:ffff:ffff:ffff
103fc46:660::/28fc46:66f:ffff:ffff:ffff:ffff:ffff:ffff
104fc46:670::/28fc46:67f:ffff:ffff:ffff:ffff:ffff:ffff
105fc46:680::/28fc46:68f:ffff:ffff:ffff:ffff:ffff:ffff
106fc46:690::/28fc46:69f:ffff:ffff:ffff:ffff:ffff:ffff
107fc46:6a0::/28fc46:6af:ffff:ffff:ffff:ffff:ffff:ffff
108fc46:6b0::/28fc46:6bf:ffff:ffff:ffff:ffff:ffff:ffff
109fc46:6c0::/28fc46:6cf:ffff:ffff:ffff:ffff:ffff:ffff
110fc46:6d0::/28fc46:6df:ffff:ffff:ffff:ffff:ffff:ffff
111fc46:6e0::/28fc46:6ef:ffff:ffff:ffff:ffff:ffff:ffff
112fc46:6f0::/28fc46:6ff:ffff:ffff:ffff:ffff:ffff:ffff
113fc46:700::/28fc46:70f:ffff:ffff:ffff:ffff:ffff:ffff
114fc46:710::/28fc46:71f:ffff:ffff:ffff:ffff:ffff:ffff
115fc46:720::/28fc46:72f:ffff:ffff:ffff:ffff:ffff:ffff
116fc46:730::/28fc46:73f:ffff:ffff:ffff:ffff:ffff:ffff
117fc46:740::/28fc46:74f:ffff:ffff:ffff:ffff:ffff:ffff
118fc46:750::/28fc46:75f:ffff:ffff:ffff:ffff:ffff:ffff
119fc46:760::/28fc46:76f:ffff:ffff:ffff:ffff:ffff:ffff
120fc46:770::/28fc46:77f:ffff:ffff:ffff:ffff:ffff:ffff
121fc46:780::/28fc46:78f:ffff:ffff:ffff:ffff:ffff:ffff
122fc46:790::/28fc46:79f:ffff:ffff:ffff:ffff:ffff:ffff
123fc46:7a0::/28fc46:7af:ffff:ffff:ffff:ffff:ffff:ffff
124fc46:7b0::/28fc46:7bf:ffff:ffff:ffff:ffff:ffff:ffff
125fc46:7c0::/28fc46:7cf:ffff:ffff:ffff:ffff:ffff:ffff
126fc46:7d0::/28fc46:7df:ffff:ffff:ffff:ffff:ffff:ffff
127fc46:7e0::/28fc46:7ef:ffff:ffff:ffff:ffff:ffff:ffff
128fc46:7f0::/28fc46:7ff:ffff:ffff:ffff:ffff:ffff:ffff
129fc46:800::/28fc46:80f:ffff:ffff:ffff:ffff:ffff:ffff
130fc46:810::/28fc46:81f:ffff:ffff:ffff:ffff:ffff:ffff
131fc46:820::/28fc46:82f:ffff:ffff:ffff:ffff:ffff:ffff
132fc46:830::/28fc46:83f:ffff:ffff:ffff:ffff:ffff:ffff
133fc46:840::/28fc46:84f:ffff:ffff:ffff:ffff:ffff:ffff
134fc46:850::/28fc46:85f:ffff:ffff:ffff:ffff:ffff:ffff
135fc46:860::/28fc46:86f:ffff:ffff:ffff:ffff:ffff:ffff
136fc46:870::/28fc46:87f:ffff:ffff:ffff:ffff:ffff:ffff
137fc46:880::/28fc46:88f:ffff:ffff:ffff:ffff:ffff:ffff
138fc46:890::/28fc46:89f:ffff:ffff:ffff:ffff:ffff:ffff
139fc46:8a0::/28fc46:8af:ffff:ffff:ffff:ffff:ffff:ffff
140fc46:8b0::/28fc46:8bf:ffff:ffff:ffff:ffff:ffff:ffff
141fc46:8c0::/28fc46:8cf:ffff:ffff:ffff:ffff:ffff:ffff
142fc46:8d0::/28fc46:8df:ffff:ffff:ffff:ffff:ffff:ffff
143fc46:8e0::/28fc46:8ef:ffff:ffff:ffff:ffff:ffff:ffff
144fc46:8f0::/28fc46:8ff:ffff:ffff:ffff:ffff:ffff:ffff
145fc46:900::/28fc46:90f:ffff:ffff:ffff:ffff:ffff:ffff
146fc46:910::/28fc46:91f:ffff:ffff:ffff:ffff:ffff:ffff
147fc46:920::/28fc46:92f:ffff:ffff:ffff:ffff:ffff:ffff
148fc46:930::/28fc46:93f:ffff:ffff:ffff:ffff:ffff:ffff
149fc46:940::/28fc46:94f:ffff:ffff:ffff:ffff:ffff:ffff
150fc46:950::/28fc46:95f:ffff:ffff:ffff:ffff:ffff:ffff
151fc46:960::/28fc46:96f:ffff:ffff:ffff:ffff:ffff:ffff
152fc46:970::/28fc46:97f:ffff:ffff:ffff:ffff:ffff:ffff
153fc46:980::/28fc46:98f:ffff:ffff:ffff:ffff:ffff:ffff
154fc46:990::/28fc46:99f:ffff:ffff:ffff:ffff:ffff:ffff
155fc46:9a0::/28fc46:9af:ffff:ffff:ffff:ffff:ffff:ffff
156fc46:9b0::/28fc46:9bf:ffff:ffff:ffff:ffff:ffff:ffff
157fc46:9c0::/28fc46:9cf:ffff:ffff:ffff:ffff:ffff:ffff
158fc46:9d0::/28fc46:9df:ffff:ffff:ffff:ffff:ffff:ffff
159fc46:9e0::/28fc46:9ef:ffff:ffff:ffff:ffff:ffff:ffff
160fc46:9f0::/28fc46:9ff:ffff:ffff:ffff:ffff:ffff:ffff
161fc46:a00::/28fc46:a0f:ffff:ffff:ffff:ffff:ffff:ffff
162fc46:a10::/28fc46:a1f:ffff:ffff:ffff:ffff:ffff:ffff
163fc46:a20::/28fc46:a2f:ffff:ffff:ffff:ffff:ffff:ffff
164fc46:a30::/28fc46:a3f:ffff:ffff:ffff:ffff:ffff:ffff
165fc46:a40::/28fc46:a4f:ffff:ffff:ffff:ffff:ffff:ffff
166fc46:a50::/28fc46:a5f:ffff:ffff:ffff:ffff:ffff:ffff
167fc46:a60::/28fc46:a6f:ffff:ffff:ffff:ffff:ffff:ffff
168fc46:a70::/28fc46:a7f:ffff:ffff:ffff:ffff:ffff:ffff
169fc46:a80::/28fc46:a8f:ffff:ffff:ffff:ffff:ffff:ffff
170fc46:a90::/28fc46:a9f:ffff:ffff:ffff:ffff:ffff:ffff
171fc46:aa0::/28fc46:aaf:ffff:ffff:ffff:ffff:ffff:ffff
172fc46:ab0::/28fc46:abf:ffff:ffff:ffff:ffff:ffff:ffff
173fc46:ac0::/28fc46:acf:ffff:ffff:ffff:ffff:ffff:ffff
174fc46:ad0::/28fc46:adf:ffff:ffff:ffff:ffff:ffff:ffff
175fc46:ae0::/28fc46:aef:ffff:ffff:ffff:ffff:ffff:ffff
176fc46:af0::/28fc46:aff:ffff:ffff:ffff:ffff:ffff:ffff
177fc46:b00::/28fc46:b0f:ffff:ffff:ffff:ffff:ffff:ffff
178fc46:b10::/28fc46:b1f:ffff:ffff:ffff:ffff:ffff:ffff
179fc46:b20::/28fc46:b2f:ffff:ffff:ffff:ffff:ffff:ffff
180fc46:b30::/28fc46:b3f:ffff:ffff:ffff:ffff:ffff:ffff
181fc46:b40::/28fc46:b4f:ffff:ffff:ffff:ffff:ffff:ffff
182fc46:b50::/28fc46:b5f:ffff:ffff:ffff:ffff:ffff:ffff
183fc46:b60::/28fc46:b6f:ffff:ffff:ffff:ffff:ffff:ffff
184fc46:b70::/28fc46:b7f:ffff:ffff:ffff:ffff:ffff:ffff
185fc46:b80::/28fc46:b8f:ffff:ffff:ffff:ffff:ffff:ffff
186fc46:b90::/28fc46:b9f:ffff:ffff:ffff:ffff:ffff:ffff
187fc46:ba0::/28fc46:baf:ffff:ffff:ffff:ffff:ffff:ffff
188fc46:bb0::/28fc46:bbf:ffff:ffff:ffff:ffff:ffff:ffff
189fc46:bc0::/28fc46:bcf:ffff:ffff:ffff:ffff:ffff:ffff
190fc46:bd0::/28fc46:bdf:ffff:ffff:ffff:ffff:ffff:ffff
191fc46:be0::/28fc46:bef:ffff:ffff:ffff:ffff:ffff:ffff
192fc46:bf0::/28fc46:bff:ffff:ffff:ffff:ffff:ffff:ffff
193fc46:c00::/28fc46:c0f:ffff:ffff:ffff:ffff:ffff:ffff
194fc46:c10::/28fc46:c1f:ffff:ffff:ffff:ffff:ffff:ffff
195fc46:c20::/28fc46:c2f:ffff:ffff:ffff:ffff:ffff:ffff
196fc46:c30::/28fc46:c3f:ffff:ffff:ffff:ffff:ffff:ffff
197fc46:c40::/28fc46:c4f:ffff:ffff:ffff:ffff:ffff:ffff
198fc46:c50::/28fc46:c5f:ffff:ffff:ffff:ffff:ffff:ffff
199fc46:c60::/28fc46:c6f:ffff:ffff:ffff:ffff:ffff:ffff
200fc46:c70::/28fc46:c7f:ffff:ffff:ffff:ffff:ffff:ffff
201fc46:c80::/28fc46:c8f:ffff:ffff:ffff:ffff:ffff:ffff
202fc46:c90::/28fc46:c9f:ffff:ffff:ffff:ffff:ffff:ffff
203fc46:ca0::/28fc46:caf:ffff:ffff:ffff:ffff:ffff:ffff
204fc46:cb0::/28fc46:cbf:ffff:ffff:ffff:ffff:ffff:ffff
205fc46:cc0::/28fc46:ccf:ffff:ffff:ffff:ffff:ffff:ffff
206fc46:cd0::/28fc46:cdf:ffff:ffff:ffff:ffff:ffff:ffff
207fc46:ce0::/28fc46:cef:ffff:ffff:ffff:ffff:ffff:ffff
208fc46:cf0::/28fc46:cff:ffff:ffff:ffff:ffff:ffff:ffff
209fc46:d00::/28fc46:d0f:ffff:ffff:ffff:ffff:ffff:ffff
210fc46:d10::/28fc46:d1f:ffff:ffff:ffff:ffff:ffff:ffff
211fc46:d20::/28fc46:d2f:ffff:ffff:ffff:ffff:ffff:ffff
212fc46:d30::/28fc46:d3f:ffff:ffff:ffff:ffff:ffff:ffff
213fc46:d40::/28fc46:d4f:ffff:ffff:ffff:ffff:ffff:ffff
214fc46:d50::/28fc46:d5f:ffff:ffff:ffff:ffff:ffff:ffff
215fc46:d60::/28fc46:d6f:ffff:ffff:ffff:ffff:ffff:ffff
216fc46:d70::/28fc46:d7f:ffff:ffff:ffff:ffff:ffff:ffff
217fc46:d80::/28fc46:d8f:ffff:ffff:ffff:ffff:ffff:ffff
218fc46:d90::/28fc46:d9f:ffff:ffff:ffff:ffff:ffff:ffff
219fc46:da0::/28fc46:daf:ffff:ffff:ffff:ffff:ffff:ffff
220fc46:db0::/28fc46:dbf:ffff:ffff:ffff:ffff:ffff:ffff
221fc46:dc0::/28fc46:dcf:ffff:ffff:ffff:ffff:ffff:ffff
222fc46:dd0::/28fc46:ddf:ffff:ffff:ffff:ffff:ffff:ffff
223fc46:de0::/28fc46:def:ffff:ffff:ffff:ffff:ffff:ffff
224fc46:df0::/28fc46:dff:ffff:ffff:ffff:ffff:ffff:ffff
225fc46:e00::/28fc46:e0f:ffff:ffff:ffff:ffff:ffff:ffff
226fc46:e10::/28fc46:e1f:ffff:ffff:ffff:ffff:ffff:ffff
227fc46:e20::/28fc46:e2f:ffff:ffff:ffff:ffff:ffff:ffff
228fc46:e30::/28fc46:e3f:ffff:ffff:ffff:ffff:ffff:ffff
229fc46:e40::/28fc46:e4f:ffff:ffff:ffff:ffff:ffff:ffff
230fc46:e50::/28fc46:e5f:ffff:ffff:ffff:ffff:ffff:ffff
231fc46:e60::/28fc46:e6f:ffff:ffff:ffff:ffff:ffff:ffff
232fc46:e70::/28fc46:e7f:ffff:ffff:ffff:ffff:ffff:ffff
233fc46:e80::/28fc46:e8f:ffff:ffff:ffff:ffff:ffff:ffff
234fc46:e90::/28fc46:e9f:ffff:ffff:ffff:ffff:ffff:ffff
235fc46:ea0::/28fc46:eaf:ffff:ffff:ffff:ffff:ffff:ffff
236fc46:eb0::/28fc46:ebf:ffff:ffff:ffff:ffff:ffff:ffff
237fc46:ec0::/28fc46:ecf:ffff:ffff:ffff:ffff:ffff:ffff
238fc46:ed0::/28fc46:edf:ffff:ffff:ffff:ffff:ffff:ffff
239fc46:ee0::/28fc46:eef:ffff:ffff:ffff:ffff:ffff:ffff
240fc46:ef0::/28fc46:eff:ffff:ffff:ffff:ffff:ffff:ffff
241fc46:f00::/28fc46:f0f:ffff:ffff:ffff:ffff:ffff:ffff
242fc46:f10::/28fc46:f1f:ffff:ffff:ffff:ffff:ffff:ffff
243fc46:f20::/28fc46:f2f:ffff:ffff:ffff:ffff:ffff:ffff
244fc46:f30::/28fc46:f3f:ffff:ffff:ffff:ffff:ffff:ffff
245fc46:f40::/28fc46:f4f:ffff:ffff:ffff:ffff:ffff:ffff
246fc46:f50::/28fc46:f5f:ffff:ffff:ffff:ffff:ffff:ffff
247fc46:f60::/28fc46:f6f:ffff:ffff:ffff:ffff:ffff:ffff
248fc46:f70::/28fc46:f7f:ffff:ffff:ffff:ffff:ffff:ffff
249fc46:f80::/28fc46:f8f:ffff:ffff:ffff:ffff:ffff:ffff
250fc46:f90::/28fc46:f9f:ffff:ffff:ffff:ffff:ffff:ffff
251fc46:fa0::/28fc46:faf:ffff:ffff:ffff:ffff:ffff:ffff
252fc46:fb0::/28fc46:fbf:ffff:ffff:ffff:ffff:ffff:ffff
253fc46:fc0::/28fc46:fcf:ffff:ffff:ffff:ffff:ffff:ffff
254fc46:fd0::/28fc46:fdf:ffff:ffff:ffff:ffff:ffff:ffff
255fc46:fe0::/28fc46:fef:ffff:ffff:ffff:ffff:ffff:ffff
256fc46:ff0::/28fc46: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.