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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
ffe8::/16
First address
ffe8::
Last address
ffe8: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
ffe8:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
8.e.f.f.ip6.arpa
Split into smaller subnets/28
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

ffe8::/16 makes 4,096 subnets of /28; the first 256 are listed.

Subnets
#SubnetLast address
1ffe8::/28ffe8:f:ffff:ffff:ffff:ffff:ffff:ffff
2ffe8:10::/28ffe8:1f:ffff:ffff:ffff:ffff:ffff:ffff
3ffe8:20::/28ffe8:2f:ffff:ffff:ffff:ffff:ffff:ffff
4ffe8:30::/28ffe8:3f:ffff:ffff:ffff:ffff:ffff:ffff
5ffe8:40::/28ffe8:4f:ffff:ffff:ffff:ffff:ffff:ffff
6ffe8:50::/28ffe8:5f:ffff:ffff:ffff:ffff:ffff:ffff
7ffe8:60::/28ffe8:6f:ffff:ffff:ffff:ffff:ffff:ffff
8ffe8:70::/28ffe8:7f:ffff:ffff:ffff:ffff:ffff:ffff
9ffe8:80::/28ffe8:8f:ffff:ffff:ffff:ffff:ffff:ffff
10ffe8:90::/28ffe8:9f:ffff:ffff:ffff:ffff:ffff:ffff
11ffe8:a0::/28ffe8:af:ffff:ffff:ffff:ffff:ffff:ffff
12ffe8:b0::/28ffe8:bf:ffff:ffff:ffff:ffff:ffff:ffff
13ffe8:c0::/28ffe8:cf:ffff:ffff:ffff:ffff:ffff:ffff
14ffe8:d0::/28ffe8:df:ffff:ffff:ffff:ffff:ffff:ffff
15ffe8:e0::/28ffe8:ef:ffff:ffff:ffff:ffff:ffff:ffff
16ffe8:f0::/28ffe8:ff:ffff:ffff:ffff:ffff:ffff:ffff
17ffe8:100::/28ffe8:10f:ffff:ffff:ffff:ffff:ffff:ffff
18ffe8:110::/28ffe8:11f:ffff:ffff:ffff:ffff:ffff:ffff
19ffe8:120::/28ffe8:12f:ffff:ffff:ffff:ffff:ffff:ffff
20ffe8:130::/28ffe8:13f:ffff:ffff:ffff:ffff:ffff:ffff
21ffe8:140::/28ffe8:14f:ffff:ffff:ffff:ffff:ffff:ffff
22ffe8:150::/28ffe8:15f:ffff:ffff:ffff:ffff:ffff:ffff
23ffe8:160::/28ffe8:16f:ffff:ffff:ffff:ffff:ffff:ffff
24ffe8:170::/28ffe8:17f:ffff:ffff:ffff:ffff:ffff:ffff
25ffe8:180::/28ffe8:18f:ffff:ffff:ffff:ffff:ffff:ffff
26ffe8:190::/28ffe8:19f:ffff:ffff:ffff:ffff:ffff:ffff
27ffe8:1a0::/28ffe8:1af:ffff:ffff:ffff:ffff:ffff:ffff
28ffe8:1b0::/28ffe8:1bf:ffff:ffff:ffff:ffff:ffff:ffff
29ffe8:1c0::/28ffe8:1cf:ffff:ffff:ffff:ffff:ffff:ffff
30ffe8:1d0::/28ffe8:1df:ffff:ffff:ffff:ffff:ffff:ffff
31ffe8:1e0::/28ffe8:1ef:ffff:ffff:ffff:ffff:ffff:ffff
32ffe8:1f0::/28ffe8:1ff:ffff:ffff:ffff:ffff:ffff:ffff
33ffe8:200::/28ffe8:20f:ffff:ffff:ffff:ffff:ffff:ffff
34ffe8:210::/28ffe8:21f:ffff:ffff:ffff:ffff:ffff:ffff
35ffe8:220::/28ffe8:22f:ffff:ffff:ffff:ffff:ffff:ffff
36ffe8:230::/28ffe8:23f:ffff:ffff:ffff:ffff:ffff:ffff
37ffe8:240::/28ffe8:24f:ffff:ffff:ffff:ffff:ffff:ffff
38ffe8:250::/28ffe8:25f:ffff:ffff:ffff:ffff:ffff:ffff
39ffe8:260::/28ffe8:26f:ffff:ffff:ffff:ffff:ffff:ffff
40ffe8:270::/28ffe8:27f:ffff:ffff:ffff:ffff:ffff:ffff
41ffe8:280::/28ffe8:28f:ffff:ffff:ffff:ffff:ffff:ffff
42ffe8:290::/28ffe8:29f:ffff:ffff:ffff:ffff:ffff:ffff
43ffe8:2a0::/28ffe8:2af:ffff:ffff:ffff:ffff:ffff:ffff
44ffe8:2b0::/28ffe8:2bf:ffff:ffff:ffff:ffff:ffff:ffff
45ffe8:2c0::/28ffe8:2cf:ffff:ffff:ffff:ffff:ffff:ffff
46ffe8:2d0::/28ffe8:2df:ffff:ffff:ffff:ffff:ffff:ffff
47ffe8:2e0::/28ffe8:2ef:ffff:ffff:ffff:ffff:ffff:ffff
48ffe8:2f0::/28ffe8:2ff:ffff:ffff:ffff:ffff:ffff:ffff
49ffe8:300::/28ffe8:30f:ffff:ffff:ffff:ffff:ffff:ffff
50ffe8:310::/28ffe8:31f:ffff:ffff:ffff:ffff:ffff:ffff
51ffe8:320::/28ffe8:32f:ffff:ffff:ffff:ffff:ffff:ffff
52ffe8:330::/28ffe8:33f:ffff:ffff:ffff:ffff:ffff:ffff
53ffe8:340::/28ffe8:34f:ffff:ffff:ffff:ffff:ffff:ffff
54ffe8:350::/28ffe8:35f:ffff:ffff:ffff:ffff:ffff:ffff
55ffe8:360::/28ffe8:36f:ffff:ffff:ffff:ffff:ffff:ffff
56ffe8:370::/28ffe8:37f:ffff:ffff:ffff:ffff:ffff:ffff
57ffe8:380::/28ffe8:38f:ffff:ffff:ffff:ffff:ffff:ffff
58ffe8:390::/28ffe8:39f:ffff:ffff:ffff:ffff:ffff:ffff
59ffe8:3a0::/28ffe8:3af:ffff:ffff:ffff:ffff:ffff:ffff
60ffe8:3b0::/28ffe8:3bf:ffff:ffff:ffff:ffff:ffff:ffff
61ffe8:3c0::/28ffe8:3cf:ffff:ffff:ffff:ffff:ffff:ffff
62ffe8:3d0::/28ffe8:3df:ffff:ffff:ffff:ffff:ffff:ffff
63ffe8:3e0::/28ffe8:3ef:ffff:ffff:ffff:ffff:ffff:ffff
64ffe8:3f0::/28ffe8:3ff:ffff:ffff:ffff:ffff:ffff:ffff
65ffe8:400::/28ffe8:40f:ffff:ffff:ffff:ffff:ffff:ffff
66ffe8:410::/28ffe8:41f:ffff:ffff:ffff:ffff:ffff:ffff
67ffe8:420::/28ffe8:42f:ffff:ffff:ffff:ffff:ffff:ffff
68ffe8:430::/28ffe8:43f:ffff:ffff:ffff:ffff:ffff:ffff
69ffe8:440::/28ffe8:44f:ffff:ffff:ffff:ffff:ffff:ffff
70ffe8:450::/28ffe8:45f:ffff:ffff:ffff:ffff:ffff:ffff
71ffe8:460::/28ffe8:46f:ffff:ffff:ffff:ffff:ffff:ffff
72ffe8:470::/28ffe8:47f:ffff:ffff:ffff:ffff:ffff:ffff
73ffe8:480::/28ffe8:48f:ffff:ffff:ffff:ffff:ffff:ffff
74ffe8:490::/28ffe8:49f:ffff:ffff:ffff:ffff:ffff:ffff
75ffe8:4a0::/28ffe8:4af:ffff:ffff:ffff:ffff:ffff:ffff
76ffe8:4b0::/28ffe8:4bf:ffff:ffff:ffff:ffff:ffff:ffff
77ffe8:4c0::/28ffe8:4cf:ffff:ffff:ffff:ffff:ffff:ffff
78ffe8:4d0::/28ffe8:4df:ffff:ffff:ffff:ffff:ffff:ffff
79ffe8:4e0::/28ffe8:4ef:ffff:ffff:ffff:ffff:ffff:ffff
80ffe8:4f0::/28ffe8:4ff:ffff:ffff:ffff:ffff:ffff:ffff
81ffe8:500::/28ffe8:50f:ffff:ffff:ffff:ffff:ffff:ffff
82ffe8:510::/28ffe8:51f:ffff:ffff:ffff:ffff:ffff:ffff
83ffe8:520::/28ffe8:52f:ffff:ffff:ffff:ffff:ffff:ffff
84ffe8:530::/28ffe8:53f:ffff:ffff:ffff:ffff:ffff:ffff
85ffe8:540::/28ffe8:54f:ffff:ffff:ffff:ffff:ffff:ffff
86ffe8:550::/28ffe8:55f:ffff:ffff:ffff:ffff:ffff:ffff
87ffe8:560::/28ffe8:56f:ffff:ffff:ffff:ffff:ffff:ffff
88ffe8:570::/28ffe8:57f:ffff:ffff:ffff:ffff:ffff:ffff
89ffe8:580::/28ffe8:58f:ffff:ffff:ffff:ffff:ffff:ffff
90ffe8:590::/28ffe8:59f:ffff:ffff:ffff:ffff:ffff:ffff
91ffe8:5a0::/28ffe8:5af:ffff:ffff:ffff:ffff:ffff:ffff
92ffe8:5b0::/28ffe8:5bf:ffff:ffff:ffff:ffff:ffff:ffff
93ffe8:5c0::/28ffe8:5cf:ffff:ffff:ffff:ffff:ffff:ffff
94ffe8:5d0::/28ffe8:5df:ffff:ffff:ffff:ffff:ffff:ffff
95ffe8:5e0::/28ffe8:5ef:ffff:ffff:ffff:ffff:ffff:ffff
96ffe8:5f0::/28ffe8:5ff:ffff:ffff:ffff:ffff:ffff:ffff
97ffe8:600::/28ffe8:60f:ffff:ffff:ffff:ffff:ffff:ffff
98ffe8:610::/28ffe8:61f:ffff:ffff:ffff:ffff:ffff:ffff
99ffe8:620::/28ffe8:62f:ffff:ffff:ffff:ffff:ffff:ffff
100ffe8:630::/28ffe8:63f:ffff:ffff:ffff:ffff:ffff:ffff
101ffe8:640::/28ffe8:64f:ffff:ffff:ffff:ffff:ffff:ffff
102ffe8:650::/28ffe8:65f:ffff:ffff:ffff:ffff:ffff:ffff
103ffe8:660::/28ffe8:66f:ffff:ffff:ffff:ffff:ffff:ffff
104ffe8:670::/28ffe8:67f:ffff:ffff:ffff:ffff:ffff:ffff
105ffe8:680::/28ffe8:68f:ffff:ffff:ffff:ffff:ffff:ffff
106ffe8:690::/28ffe8:69f:ffff:ffff:ffff:ffff:ffff:ffff
107ffe8:6a0::/28ffe8:6af:ffff:ffff:ffff:ffff:ffff:ffff
108ffe8:6b0::/28ffe8:6bf:ffff:ffff:ffff:ffff:ffff:ffff
109ffe8:6c0::/28ffe8:6cf:ffff:ffff:ffff:ffff:ffff:ffff
110ffe8:6d0::/28ffe8:6df:ffff:ffff:ffff:ffff:ffff:ffff
111ffe8:6e0::/28ffe8:6ef:ffff:ffff:ffff:ffff:ffff:ffff
112ffe8:6f0::/28ffe8:6ff:ffff:ffff:ffff:ffff:ffff:ffff
113ffe8:700::/28ffe8:70f:ffff:ffff:ffff:ffff:ffff:ffff
114ffe8:710::/28ffe8:71f:ffff:ffff:ffff:ffff:ffff:ffff
115ffe8:720::/28ffe8:72f:ffff:ffff:ffff:ffff:ffff:ffff
116ffe8:730::/28ffe8:73f:ffff:ffff:ffff:ffff:ffff:ffff
117ffe8:740::/28ffe8:74f:ffff:ffff:ffff:ffff:ffff:ffff
118ffe8:750::/28ffe8:75f:ffff:ffff:ffff:ffff:ffff:ffff
119ffe8:760::/28ffe8:76f:ffff:ffff:ffff:ffff:ffff:ffff
120ffe8:770::/28ffe8:77f:ffff:ffff:ffff:ffff:ffff:ffff
121ffe8:780::/28ffe8:78f:ffff:ffff:ffff:ffff:ffff:ffff
122ffe8:790::/28ffe8:79f:ffff:ffff:ffff:ffff:ffff:ffff
123ffe8:7a0::/28ffe8:7af:ffff:ffff:ffff:ffff:ffff:ffff
124ffe8:7b0::/28ffe8:7bf:ffff:ffff:ffff:ffff:ffff:ffff
125ffe8:7c0::/28ffe8:7cf:ffff:ffff:ffff:ffff:ffff:ffff
126ffe8:7d0::/28ffe8:7df:ffff:ffff:ffff:ffff:ffff:ffff
127ffe8:7e0::/28ffe8:7ef:ffff:ffff:ffff:ffff:ffff:ffff
128ffe8:7f0::/28ffe8:7ff:ffff:ffff:ffff:ffff:ffff:ffff
129ffe8:800::/28ffe8:80f:ffff:ffff:ffff:ffff:ffff:ffff
130ffe8:810::/28ffe8:81f:ffff:ffff:ffff:ffff:ffff:ffff
131ffe8:820::/28ffe8:82f:ffff:ffff:ffff:ffff:ffff:ffff
132ffe8:830::/28ffe8:83f:ffff:ffff:ffff:ffff:ffff:ffff
133ffe8:840::/28ffe8:84f:ffff:ffff:ffff:ffff:ffff:ffff
134ffe8:850::/28ffe8:85f:ffff:ffff:ffff:ffff:ffff:ffff
135ffe8:860::/28ffe8:86f:ffff:ffff:ffff:ffff:ffff:ffff
136ffe8:870::/28ffe8:87f:ffff:ffff:ffff:ffff:ffff:ffff
137ffe8:880::/28ffe8:88f:ffff:ffff:ffff:ffff:ffff:ffff
138ffe8:890::/28ffe8:89f:ffff:ffff:ffff:ffff:ffff:ffff
139ffe8:8a0::/28ffe8:8af:ffff:ffff:ffff:ffff:ffff:ffff
140ffe8:8b0::/28ffe8:8bf:ffff:ffff:ffff:ffff:ffff:ffff
141ffe8:8c0::/28ffe8:8cf:ffff:ffff:ffff:ffff:ffff:ffff
142ffe8:8d0::/28ffe8:8df:ffff:ffff:ffff:ffff:ffff:ffff
143ffe8:8e0::/28ffe8:8ef:ffff:ffff:ffff:ffff:ffff:ffff
144ffe8:8f0::/28ffe8:8ff:ffff:ffff:ffff:ffff:ffff:ffff
145ffe8:900::/28ffe8:90f:ffff:ffff:ffff:ffff:ffff:ffff
146ffe8:910::/28ffe8:91f:ffff:ffff:ffff:ffff:ffff:ffff
147ffe8:920::/28ffe8:92f:ffff:ffff:ffff:ffff:ffff:ffff
148ffe8:930::/28ffe8:93f:ffff:ffff:ffff:ffff:ffff:ffff
149ffe8:940::/28ffe8:94f:ffff:ffff:ffff:ffff:ffff:ffff
150ffe8:950::/28ffe8:95f:ffff:ffff:ffff:ffff:ffff:ffff
151ffe8:960::/28ffe8:96f:ffff:ffff:ffff:ffff:ffff:ffff
152ffe8:970::/28ffe8:97f:ffff:ffff:ffff:ffff:ffff:ffff
153ffe8:980::/28ffe8:98f:ffff:ffff:ffff:ffff:ffff:ffff
154ffe8:990::/28ffe8:99f:ffff:ffff:ffff:ffff:ffff:ffff
155ffe8:9a0::/28ffe8:9af:ffff:ffff:ffff:ffff:ffff:ffff
156ffe8:9b0::/28ffe8:9bf:ffff:ffff:ffff:ffff:ffff:ffff
157ffe8:9c0::/28ffe8:9cf:ffff:ffff:ffff:ffff:ffff:ffff
158ffe8:9d0::/28ffe8:9df:ffff:ffff:ffff:ffff:ffff:ffff
159ffe8:9e0::/28ffe8:9ef:ffff:ffff:ffff:ffff:ffff:ffff
160ffe8:9f0::/28ffe8:9ff:ffff:ffff:ffff:ffff:ffff:ffff
161ffe8:a00::/28ffe8:a0f:ffff:ffff:ffff:ffff:ffff:ffff
162ffe8:a10::/28ffe8:a1f:ffff:ffff:ffff:ffff:ffff:ffff
163ffe8:a20::/28ffe8:a2f:ffff:ffff:ffff:ffff:ffff:ffff
164ffe8:a30::/28ffe8:a3f:ffff:ffff:ffff:ffff:ffff:ffff
165ffe8:a40::/28ffe8:a4f:ffff:ffff:ffff:ffff:ffff:ffff
166ffe8:a50::/28ffe8:a5f:ffff:ffff:ffff:ffff:ffff:ffff
167ffe8:a60::/28ffe8:a6f:ffff:ffff:ffff:ffff:ffff:ffff
168ffe8:a70::/28ffe8:a7f:ffff:ffff:ffff:ffff:ffff:ffff
169ffe8:a80::/28ffe8:a8f:ffff:ffff:ffff:ffff:ffff:ffff
170ffe8:a90::/28ffe8:a9f:ffff:ffff:ffff:ffff:ffff:ffff
171ffe8:aa0::/28ffe8:aaf:ffff:ffff:ffff:ffff:ffff:ffff
172ffe8:ab0::/28ffe8:abf:ffff:ffff:ffff:ffff:ffff:ffff
173ffe8:ac0::/28ffe8:acf:ffff:ffff:ffff:ffff:ffff:ffff
174ffe8:ad0::/28ffe8:adf:ffff:ffff:ffff:ffff:ffff:ffff
175ffe8:ae0::/28ffe8:aef:ffff:ffff:ffff:ffff:ffff:ffff
176ffe8:af0::/28ffe8:aff:ffff:ffff:ffff:ffff:ffff:ffff
177ffe8:b00::/28ffe8:b0f:ffff:ffff:ffff:ffff:ffff:ffff
178ffe8:b10::/28ffe8:b1f:ffff:ffff:ffff:ffff:ffff:ffff
179ffe8:b20::/28ffe8:b2f:ffff:ffff:ffff:ffff:ffff:ffff
180ffe8:b30::/28ffe8:b3f:ffff:ffff:ffff:ffff:ffff:ffff
181ffe8:b40::/28ffe8:b4f:ffff:ffff:ffff:ffff:ffff:ffff
182ffe8:b50::/28ffe8:b5f:ffff:ffff:ffff:ffff:ffff:ffff
183ffe8:b60::/28ffe8:b6f:ffff:ffff:ffff:ffff:ffff:ffff
184ffe8:b70::/28ffe8:b7f:ffff:ffff:ffff:ffff:ffff:ffff
185ffe8:b80::/28ffe8:b8f:ffff:ffff:ffff:ffff:ffff:ffff
186ffe8:b90::/28ffe8:b9f:ffff:ffff:ffff:ffff:ffff:ffff
187ffe8:ba0::/28ffe8:baf:ffff:ffff:ffff:ffff:ffff:ffff
188ffe8:bb0::/28ffe8:bbf:ffff:ffff:ffff:ffff:ffff:ffff
189ffe8:bc0::/28ffe8:bcf:ffff:ffff:ffff:ffff:ffff:ffff
190ffe8:bd0::/28ffe8:bdf:ffff:ffff:ffff:ffff:ffff:ffff
191ffe8:be0::/28ffe8:bef:ffff:ffff:ffff:ffff:ffff:ffff
192ffe8:bf0::/28ffe8:bff:ffff:ffff:ffff:ffff:ffff:ffff
193ffe8:c00::/28ffe8:c0f:ffff:ffff:ffff:ffff:ffff:ffff
194ffe8:c10::/28ffe8:c1f:ffff:ffff:ffff:ffff:ffff:ffff
195ffe8:c20::/28ffe8:c2f:ffff:ffff:ffff:ffff:ffff:ffff
196ffe8:c30::/28ffe8:c3f:ffff:ffff:ffff:ffff:ffff:ffff
197ffe8:c40::/28ffe8:c4f:ffff:ffff:ffff:ffff:ffff:ffff
198ffe8:c50::/28ffe8:c5f:ffff:ffff:ffff:ffff:ffff:ffff
199ffe8:c60::/28ffe8:c6f:ffff:ffff:ffff:ffff:ffff:ffff
200ffe8:c70::/28ffe8:c7f:ffff:ffff:ffff:ffff:ffff:ffff
201ffe8:c80::/28ffe8:c8f:ffff:ffff:ffff:ffff:ffff:ffff
202ffe8:c90::/28ffe8:c9f:ffff:ffff:ffff:ffff:ffff:ffff
203ffe8:ca0::/28ffe8:caf:ffff:ffff:ffff:ffff:ffff:ffff
204ffe8:cb0::/28ffe8:cbf:ffff:ffff:ffff:ffff:ffff:ffff
205ffe8:cc0::/28ffe8:ccf:ffff:ffff:ffff:ffff:ffff:ffff
206ffe8:cd0::/28ffe8:cdf:ffff:ffff:ffff:ffff:ffff:ffff
207ffe8:ce0::/28ffe8:cef:ffff:ffff:ffff:ffff:ffff:ffff
208ffe8:cf0::/28ffe8:cff:ffff:ffff:ffff:ffff:ffff:ffff
209ffe8:d00::/28ffe8:d0f:ffff:ffff:ffff:ffff:ffff:ffff
210ffe8:d10::/28ffe8:d1f:ffff:ffff:ffff:ffff:ffff:ffff
211ffe8:d20::/28ffe8:d2f:ffff:ffff:ffff:ffff:ffff:ffff
212ffe8:d30::/28ffe8:d3f:ffff:ffff:ffff:ffff:ffff:ffff
213ffe8:d40::/28ffe8:d4f:ffff:ffff:ffff:ffff:ffff:ffff
214ffe8:d50::/28ffe8:d5f:ffff:ffff:ffff:ffff:ffff:ffff
215ffe8:d60::/28ffe8:d6f:ffff:ffff:ffff:ffff:ffff:ffff
216ffe8:d70::/28ffe8:d7f:ffff:ffff:ffff:ffff:ffff:ffff
217ffe8:d80::/28ffe8:d8f:ffff:ffff:ffff:ffff:ffff:ffff
218ffe8:d90::/28ffe8:d9f:ffff:ffff:ffff:ffff:ffff:ffff
219ffe8:da0::/28ffe8:daf:ffff:ffff:ffff:ffff:ffff:ffff
220ffe8:db0::/28ffe8:dbf:ffff:ffff:ffff:ffff:ffff:ffff
221ffe8:dc0::/28ffe8:dcf:ffff:ffff:ffff:ffff:ffff:ffff
222ffe8:dd0::/28ffe8:ddf:ffff:ffff:ffff:ffff:ffff:ffff
223ffe8:de0::/28ffe8:def:ffff:ffff:ffff:ffff:ffff:ffff
224ffe8:df0::/28ffe8:dff:ffff:ffff:ffff:ffff:ffff:ffff
225ffe8:e00::/28ffe8:e0f:ffff:ffff:ffff:ffff:ffff:ffff
226ffe8:e10::/28ffe8:e1f:ffff:ffff:ffff:ffff:ffff:ffff
227ffe8:e20::/28ffe8:e2f:ffff:ffff:ffff:ffff:ffff:ffff
228ffe8:e30::/28ffe8:e3f:ffff:ffff:ffff:ffff:ffff:ffff
229ffe8:e40::/28ffe8:e4f:ffff:ffff:ffff:ffff:ffff:ffff
230ffe8:e50::/28ffe8:e5f:ffff:ffff:ffff:ffff:ffff:ffff
231ffe8:e60::/28ffe8:e6f:ffff:ffff:ffff:ffff:ffff:ffff
232ffe8:e70::/28ffe8:e7f:ffff:ffff:ffff:ffff:ffff:ffff
233ffe8:e80::/28ffe8:e8f:ffff:ffff:ffff:ffff:ffff:ffff
234ffe8:e90::/28ffe8:e9f:ffff:ffff:ffff:ffff:ffff:ffff
235ffe8:ea0::/28ffe8:eaf:ffff:ffff:ffff:ffff:ffff:ffff
236ffe8:eb0::/28ffe8:ebf:ffff:ffff:ffff:ffff:ffff:ffff
237ffe8:ec0::/28ffe8:ecf:ffff:ffff:ffff:ffff:ffff:ffff
238ffe8:ed0::/28ffe8:edf:ffff:ffff:ffff:ffff:ffff:ffff
239ffe8:ee0::/28ffe8:eef:ffff:ffff:ffff:ffff:ffff:ffff
240ffe8:ef0::/28ffe8:eff:ffff:ffff:ffff:ffff:ffff:ffff
241ffe8:f00::/28ffe8:f0f:ffff:ffff:ffff:ffff:ffff:ffff
242ffe8:f10::/28ffe8:f1f:ffff:ffff:ffff:ffff:ffff:ffff
243ffe8:f20::/28ffe8:f2f:ffff:ffff:ffff:ffff:ffff:ffff
244ffe8:f30::/28ffe8:f3f:ffff:ffff:ffff:ffff:ffff:ffff
245ffe8:f40::/28ffe8:f4f:ffff:ffff:ffff:ffff:ffff:ffff
246ffe8:f50::/28ffe8:f5f:ffff:ffff:ffff:ffff:ffff:ffff
247ffe8:f60::/28ffe8:f6f:ffff:ffff:ffff:ffff:ffff:ffff
248ffe8:f70::/28ffe8:f7f:ffff:ffff:ffff:ffff:ffff:ffff
249ffe8:f80::/28ffe8:f8f:ffff:ffff:ffff:ffff:ffff:ffff
250ffe8:f90::/28ffe8:f9f:ffff:ffff:ffff:ffff:ffff:ffff
251ffe8:fa0::/28ffe8:faf:ffff:ffff:ffff:ffff:ffff:ffff
252ffe8:fb0::/28ffe8:fbf:ffff:ffff:ffff:ffff:ffff:ffff
253ffe8:fc0::/28ffe8:fcf:ffff:ffff:ffff:ffff:ffff:ffff
254ffe8:fd0::/28ffe8:fdf:ffff:ffff:ffff:ffff:ffff:ffff
255ffe8:fe0::/28ffe8:fef:ffff:ffff:ffff:ffff:ffff:ffff
256ffe8:ff0::/28ffe8: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.