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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
fe8c::/14
First address
fe8c::
Last address
fe8f: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
fe8c:0000:0000:0000:0000:0000:0000:0000
Type
Link-local fe80::/10
Every IPv6 interface has one; not routed
Reverse DNS zones
c.8.e.f.ip6.arpa
d.8.e.f.ip6.arpa
e.8.e.f.ip6.arpa
f.8.e.f.ip6.arpa
/14 is not on a 4-bit boundary, so it takes 4 /16 zones.
Split into smaller subnets/24
/15 (2)/16 (4)/17 (8)/18 (16)/20 (64)/24 (1,024)/28 (16,384)

fe8c::/14 makes 1,024 subnets of /24; the first 256 are listed.

Subnets
#SubnetLast address
1fe8c::/24fe8c:ff:ffff:ffff:ffff:ffff:ffff:ffff
2fe8c:100::/24fe8c:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3fe8c:200::/24fe8c:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4fe8c:300::/24fe8c:3ff:ffff:ffff:ffff:ffff:ffff:ffff
5fe8c:400::/24fe8c:4ff:ffff:ffff:ffff:ffff:ffff:ffff
6fe8c:500::/24fe8c:5ff:ffff:ffff:ffff:ffff:ffff:ffff
7fe8c:600::/24fe8c:6ff:ffff:ffff:ffff:ffff:ffff:ffff
8fe8c:700::/24fe8c:7ff:ffff:ffff:ffff:ffff:ffff:ffff
9fe8c:800::/24fe8c:8ff:ffff:ffff:ffff:ffff:ffff:ffff
10fe8c:900::/24fe8c:9ff:ffff:ffff:ffff:ffff:ffff:ffff
11fe8c:a00::/24fe8c:aff:ffff:ffff:ffff:ffff:ffff:ffff
12fe8c:b00::/24fe8c:bff:ffff:ffff:ffff:ffff:ffff:ffff
13fe8c:c00::/24fe8c:cff:ffff:ffff:ffff:ffff:ffff:ffff
14fe8c:d00::/24fe8c:dff:ffff:ffff:ffff:ffff:ffff:ffff
15fe8c:e00::/24fe8c:eff:ffff:ffff:ffff:ffff:ffff:ffff
16fe8c:f00::/24fe8c:fff:ffff:ffff:ffff:ffff:ffff:ffff
17fe8c:1000::/24fe8c:10ff:ffff:ffff:ffff:ffff:ffff:ffff
18fe8c:1100::/24fe8c:11ff:ffff:ffff:ffff:ffff:ffff:ffff
19fe8c:1200::/24fe8c:12ff:ffff:ffff:ffff:ffff:ffff:ffff
20fe8c:1300::/24fe8c:13ff:ffff:ffff:ffff:ffff:ffff:ffff
21fe8c:1400::/24fe8c:14ff:ffff:ffff:ffff:ffff:ffff:ffff
22fe8c:1500::/24fe8c:15ff:ffff:ffff:ffff:ffff:ffff:ffff
23fe8c:1600::/24fe8c:16ff:ffff:ffff:ffff:ffff:ffff:ffff
24fe8c:1700::/24fe8c:17ff:ffff:ffff:ffff:ffff:ffff:ffff
25fe8c:1800::/24fe8c:18ff:ffff:ffff:ffff:ffff:ffff:ffff
26fe8c:1900::/24fe8c:19ff:ffff:ffff:ffff:ffff:ffff:ffff
27fe8c:1a00::/24fe8c:1aff:ffff:ffff:ffff:ffff:ffff:ffff
28fe8c:1b00::/24fe8c:1bff:ffff:ffff:ffff:ffff:ffff:ffff
29fe8c:1c00::/24fe8c:1cff:ffff:ffff:ffff:ffff:ffff:ffff
30fe8c:1d00::/24fe8c:1dff:ffff:ffff:ffff:ffff:ffff:ffff
31fe8c:1e00::/24fe8c:1eff:ffff:ffff:ffff:ffff:ffff:ffff
32fe8c:1f00::/24fe8c:1fff:ffff:ffff:ffff:ffff:ffff:ffff
33fe8c:2000::/24fe8c:20ff:ffff:ffff:ffff:ffff:ffff:ffff
34fe8c:2100::/24fe8c:21ff:ffff:ffff:ffff:ffff:ffff:ffff
35fe8c:2200::/24fe8c:22ff:ffff:ffff:ffff:ffff:ffff:ffff
36fe8c:2300::/24fe8c:23ff:ffff:ffff:ffff:ffff:ffff:ffff
37fe8c:2400::/24fe8c:24ff:ffff:ffff:ffff:ffff:ffff:ffff
38fe8c:2500::/24fe8c:25ff:ffff:ffff:ffff:ffff:ffff:ffff
39fe8c:2600::/24fe8c:26ff:ffff:ffff:ffff:ffff:ffff:ffff
40fe8c:2700::/24fe8c:27ff:ffff:ffff:ffff:ffff:ffff:ffff
41fe8c:2800::/24fe8c:28ff:ffff:ffff:ffff:ffff:ffff:ffff
42fe8c:2900::/24fe8c:29ff:ffff:ffff:ffff:ffff:ffff:ffff
43fe8c:2a00::/24fe8c:2aff:ffff:ffff:ffff:ffff:ffff:ffff
44fe8c:2b00::/24fe8c:2bff:ffff:ffff:ffff:ffff:ffff:ffff
45fe8c:2c00::/24fe8c:2cff:ffff:ffff:ffff:ffff:ffff:ffff
46fe8c:2d00::/24fe8c:2dff:ffff:ffff:ffff:ffff:ffff:ffff
47fe8c:2e00::/24fe8c:2eff:ffff:ffff:ffff:ffff:ffff:ffff
48fe8c:2f00::/24fe8c:2fff:ffff:ffff:ffff:ffff:ffff:ffff
49fe8c:3000::/24fe8c:30ff:ffff:ffff:ffff:ffff:ffff:ffff
50fe8c:3100::/24fe8c:31ff:ffff:ffff:ffff:ffff:ffff:ffff
51fe8c:3200::/24fe8c:32ff:ffff:ffff:ffff:ffff:ffff:ffff
52fe8c:3300::/24fe8c:33ff:ffff:ffff:ffff:ffff:ffff:ffff
53fe8c:3400::/24fe8c:34ff:ffff:ffff:ffff:ffff:ffff:ffff
54fe8c:3500::/24fe8c:35ff:ffff:ffff:ffff:ffff:ffff:ffff
55fe8c:3600::/24fe8c:36ff:ffff:ffff:ffff:ffff:ffff:ffff
56fe8c:3700::/24fe8c:37ff:ffff:ffff:ffff:ffff:ffff:ffff
57fe8c:3800::/24fe8c:38ff:ffff:ffff:ffff:ffff:ffff:ffff
58fe8c:3900::/24fe8c:39ff:ffff:ffff:ffff:ffff:ffff:ffff
59fe8c:3a00::/24fe8c:3aff:ffff:ffff:ffff:ffff:ffff:ffff
60fe8c:3b00::/24fe8c:3bff:ffff:ffff:ffff:ffff:ffff:ffff
61fe8c:3c00::/24fe8c:3cff:ffff:ffff:ffff:ffff:ffff:ffff
62fe8c:3d00::/24fe8c:3dff:ffff:ffff:ffff:ffff:ffff:ffff
63fe8c:3e00::/24fe8c:3eff:ffff:ffff:ffff:ffff:ffff:ffff
64fe8c:3f00::/24fe8c:3fff:ffff:ffff:ffff:ffff:ffff:ffff
65fe8c:4000::/24fe8c:40ff:ffff:ffff:ffff:ffff:ffff:ffff
66fe8c:4100::/24fe8c:41ff:ffff:ffff:ffff:ffff:ffff:ffff
67fe8c:4200::/24fe8c:42ff:ffff:ffff:ffff:ffff:ffff:ffff
68fe8c:4300::/24fe8c:43ff:ffff:ffff:ffff:ffff:ffff:ffff
69fe8c:4400::/24fe8c:44ff:ffff:ffff:ffff:ffff:ffff:ffff
70fe8c:4500::/24fe8c:45ff:ffff:ffff:ffff:ffff:ffff:ffff
71fe8c:4600::/24fe8c:46ff:ffff:ffff:ffff:ffff:ffff:ffff
72fe8c:4700::/24fe8c:47ff:ffff:ffff:ffff:ffff:ffff:ffff
73fe8c:4800::/24fe8c:48ff:ffff:ffff:ffff:ffff:ffff:ffff
74fe8c:4900::/24fe8c:49ff:ffff:ffff:ffff:ffff:ffff:ffff
75fe8c:4a00::/24fe8c:4aff:ffff:ffff:ffff:ffff:ffff:ffff
76fe8c:4b00::/24fe8c:4bff:ffff:ffff:ffff:ffff:ffff:ffff
77fe8c:4c00::/24fe8c:4cff:ffff:ffff:ffff:ffff:ffff:ffff
78fe8c:4d00::/24fe8c:4dff:ffff:ffff:ffff:ffff:ffff:ffff
79fe8c:4e00::/24fe8c:4eff:ffff:ffff:ffff:ffff:ffff:ffff
80fe8c:4f00::/24fe8c:4fff:ffff:ffff:ffff:ffff:ffff:ffff
81fe8c:5000::/24fe8c:50ff:ffff:ffff:ffff:ffff:ffff:ffff
82fe8c:5100::/24fe8c:51ff:ffff:ffff:ffff:ffff:ffff:ffff
83fe8c:5200::/24fe8c:52ff:ffff:ffff:ffff:ffff:ffff:ffff
84fe8c:5300::/24fe8c:53ff:ffff:ffff:ffff:ffff:ffff:ffff
85fe8c:5400::/24fe8c:54ff:ffff:ffff:ffff:ffff:ffff:ffff
86fe8c:5500::/24fe8c:55ff:ffff:ffff:ffff:ffff:ffff:ffff
87fe8c:5600::/24fe8c:56ff:ffff:ffff:ffff:ffff:ffff:ffff
88fe8c:5700::/24fe8c:57ff:ffff:ffff:ffff:ffff:ffff:ffff
89fe8c:5800::/24fe8c:58ff:ffff:ffff:ffff:ffff:ffff:ffff
90fe8c:5900::/24fe8c:59ff:ffff:ffff:ffff:ffff:ffff:ffff
91fe8c:5a00::/24fe8c:5aff:ffff:ffff:ffff:ffff:ffff:ffff
92fe8c:5b00::/24fe8c:5bff:ffff:ffff:ffff:ffff:ffff:ffff
93fe8c:5c00::/24fe8c:5cff:ffff:ffff:ffff:ffff:ffff:ffff
94fe8c:5d00::/24fe8c:5dff:ffff:ffff:ffff:ffff:ffff:ffff
95fe8c:5e00::/24fe8c:5eff:ffff:ffff:ffff:ffff:ffff:ffff
96fe8c:5f00::/24fe8c:5fff:ffff:ffff:ffff:ffff:ffff:ffff
97fe8c:6000::/24fe8c:60ff:ffff:ffff:ffff:ffff:ffff:ffff
98fe8c:6100::/24fe8c:61ff:ffff:ffff:ffff:ffff:ffff:ffff
99fe8c:6200::/24fe8c:62ff:ffff:ffff:ffff:ffff:ffff:ffff
100fe8c:6300::/24fe8c:63ff:ffff:ffff:ffff:ffff:ffff:ffff
101fe8c:6400::/24fe8c:64ff:ffff:ffff:ffff:ffff:ffff:ffff
102fe8c:6500::/24fe8c:65ff:ffff:ffff:ffff:ffff:ffff:ffff
103fe8c:6600::/24fe8c:66ff:ffff:ffff:ffff:ffff:ffff:ffff
104fe8c:6700::/24fe8c:67ff:ffff:ffff:ffff:ffff:ffff:ffff
105fe8c:6800::/24fe8c:68ff:ffff:ffff:ffff:ffff:ffff:ffff
106fe8c:6900::/24fe8c:69ff:ffff:ffff:ffff:ffff:ffff:ffff
107fe8c:6a00::/24fe8c:6aff:ffff:ffff:ffff:ffff:ffff:ffff
108fe8c:6b00::/24fe8c:6bff:ffff:ffff:ffff:ffff:ffff:ffff
109fe8c:6c00::/24fe8c:6cff:ffff:ffff:ffff:ffff:ffff:ffff
110fe8c:6d00::/24fe8c:6dff:ffff:ffff:ffff:ffff:ffff:ffff
111fe8c:6e00::/24fe8c:6eff:ffff:ffff:ffff:ffff:ffff:ffff
112fe8c:6f00::/24fe8c:6fff:ffff:ffff:ffff:ffff:ffff:ffff
113fe8c:7000::/24fe8c:70ff:ffff:ffff:ffff:ffff:ffff:ffff
114fe8c:7100::/24fe8c:71ff:ffff:ffff:ffff:ffff:ffff:ffff
115fe8c:7200::/24fe8c:72ff:ffff:ffff:ffff:ffff:ffff:ffff
116fe8c:7300::/24fe8c:73ff:ffff:ffff:ffff:ffff:ffff:ffff
117fe8c:7400::/24fe8c:74ff:ffff:ffff:ffff:ffff:ffff:ffff
118fe8c:7500::/24fe8c:75ff:ffff:ffff:ffff:ffff:ffff:ffff
119fe8c:7600::/24fe8c:76ff:ffff:ffff:ffff:ffff:ffff:ffff
120fe8c:7700::/24fe8c:77ff:ffff:ffff:ffff:ffff:ffff:ffff
121fe8c:7800::/24fe8c:78ff:ffff:ffff:ffff:ffff:ffff:ffff
122fe8c:7900::/24fe8c:79ff:ffff:ffff:ffff:ffff:ffff:ffff
123fe8c:7a00::/24fe8c:7aff:ffff:ffff:ffff:ffff:ffff:ffff
124fe8c:7b00::/24fe8c:7bff:ffff:ffff:ffff:ffff:ffff:ffff
125fe8c:7c00::/24fe8c:7cff:ffff:ffff:ffff:ffff:ffff:ffff
126fe8c:7d00::/24fe8c:7dff:ffff:ffff:ffff:ffff:ffff:ffff
127fe8c:7e00::/24fe8c:7eff:ffff:ffff:ffff:ffff:ffff:ffff
128fe8c:7f00::/24fe8c:7fff:ffff:ffff:ffff:ffff:ffff:ffff
129fe8c:8000::/24fe8c:80ff:ffff:ffff:ffff:ffff:ffff:ffff
130fe8c:8100::/24fe8c:81ff:ffff:ffff:ffff:ffff:ffff:ffff
131fe8c:8200::/24fe8c:82ff:ffff:ffff:ffff:ffff:ffff:ffff
132fe8c:8300::/24fe8c:83ff:ffff:ffff:ffff:ffff:ffff:ffff
133fe8c:8400::/24fe8c:84ff:ffff:ffff:ffff:ffff:ffff:ffff
134fe8c:8500::/24fe8c:85ff:ffff:ffff:ffff:ffff:ffff:ffff
135fe8c:8600::/24fe8c:86ff:ffff:ffff:ffff:ffff:ffff:ffff
136fe8c:8700::/24fe8c:87ff:ffff:ffff:ffff:ffff:ffff:ffff
137fe8c:8800::/24fe8c:88ff:ffff:ffff:ffff:ffff:ffff:ffff
138fe8c:8900::/24fe8c:89ff:ffff:ffff:ffff:ffff:ffff:ffff
139fe8c:8a00::/24fe8c:8aff:ffff:ffff:ffff:ffff:ffff:ffff
140fe8c:8b00::/24fe8c:8bff:ffff:ffff:ffff:ffff:ffff:ffff
141fe8c:8c00::/24fe8c:8cff:ffff:ffff:ffff:ffff:ffff:ffff
142fe8c:8d00::/24fe8c:8dff:ffff:ffff:ffff:ffff:ffff:ffff
143fe8c:8e00::/24fe8c:8eff:ffff:ffff:ffff:ffff:ffff:ffff
144fe8c:8f00::/24fe8c:8fff:ffff:ffff:ffff:ffff:ffff:ffff
145fe8c:9000::/24fe8c:90ff:ffff:ffff:ffff:ffff:ffff:ffff
146fe8c:9100::/24fe8c:91ff:ffff:ffff:ffff:ffff:ffff:ffff
147fe8c:9200::/24fe8c:92ff:ffff:ffff:ffff:ffff:ffff:ffff
148fe8c:9300::/24fe8c:93ff:ffff:ffff:ffff:ffff:ffff:ffff
149fe8c:9400::/24fe8c:94ff:ffff:ffff:ffff:ffff:ffff:ffff
150fe8c:9500::/24fe8c:95ff:ffff:ffff:ffff:ffff:ffff:ffff
151fe8c:9600::/24fe8c:96ff:ffff:ffff:ffff:ffff:ffff:ffff
152fe8c:9700::/24fe8c:97ff:ffff:ffff:ffff:ffff:ffff:ffff
153fe8c:9800::/24fe8c:98ff:ffff:ffff:ffff:ffff:ffff:ffff
154fe8c:9900::/24fe8c:99ff:ffff:ffff:ffff:ffff:ffff:ffff
155fe8c:9a00::/24fe8c:9aff:ffff:ffff:ffff:ffff:ffff:ffff
156fe8c:9b00::/24fe8c:9bff:ffff:ffff:ffff:ffff:ffff:ffff
157fe8c:9c00::/24fe8c:9cff:ffff:ffff:ffff:ffff:ffff:ffff
158fe8c:9d00::/24fe8c:9dff:ffff:ffff:ffff:ffff:ffff:ffff
159fe8c:9e00::/24fe8c:9eff:ffff:ffff:ffff:ffff:ffff:ffff
160fe8c:9f00::/24fe8c:9fff:ffff:ffff:ffff:ffff:ffff:ffff
161fe8c:a000::/24fe8c:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
162fe8c:a100::/24fe8c:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
163fe8c:a200::/24fe8c:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
164fe8c:a300::/24fe8c:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
165fe8c:a400::/24fe8c:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
166fe8c:a500::/24fe8c:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
167fe8c:a600::/24fe8c:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
168fe8c:a700::/24fe8c:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
169fe8c:a800::/24fe8c:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
170fe8c:a900::/24fe8c:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
171fe8c:aa00::/24fe8c:aaff:ffff:ffff:ffff:ffff:ffff:ffff
172fe8c:ab00::/24fe8c:abff:ffff:ffff:ffff:ffff:ffff:ffff
173fe8c:ac00::/24fe8c:acff:ffff:ffff:ffff:ffff:ffff:ffff
174fe8c:ad00::/24fe8c:adff:ffff:ffff:ffff:ffff:ffff:ffff
175fe8c:ae00::/24fe8c:aeff:ffff:ffff:ffff:ffff:ffff:ffff
176fe8c:af00::/24fe8c:afff:ffff:ffff:ffff:ffff:ffff:ffff
177fe8c:b000::/24fe8c:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
178fe8c:b100::/24fe8c:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
179fe8c:b200::/24fe8c:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
180fe8c:b300::/24fe8c:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
181fe8c:b400::/24fe8c:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
182fe8c:b500::/24fe8c:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
183fe8c:b600::/24fe8c:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
184fe8c:b700::/24fe8c:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
185fe8c:b800::/24fe8c:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
186fe8c:b900::/24fe8c:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
187fe8c:ba00::/24fe8c:baff:ffff:ffff:ffff:ffff:ffff:ffff
188fe8c:bb00::/24fe8c:bbff:ffff:ffff:ffff:ffff:ffff:ffff
189fe8c:bc00::/24fe8c:bcff:ffff:ffff:ffff:ffff:ffff:ffff
190fe8c:bd00::/24fe8c:bdff:ffff:ffff:ffff:ffff:ffff:ffff
191fe8c:be00::/24fe8c:beff:ffff:ffff:ffff:ffff:ffff:ffff
192fe8c:bf00::/24fe8c:bfff:ffff:ffff:ffff:ffff:ffff:ffff
193fe8c:c000::/24fe8c:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
194fe8c:c100::/24fe8c:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
195fe8c:c200::/24fe8c:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
196fe8c:c300::/24fe8c:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
197fe8c:c400::/24fe8c:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
198fe8c:c500::/24fe8c:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
199fe8c:c600::/24fe8c:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
200fe8c:c700::/24fe8c:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
201fe8c:c800::/24fe8c:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
202fe8c:c900::/24fe8c:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
203fe8c:ca00::/24fe8c:caff:ffff:ffff:ffff:ffff:ffff:ffff
204fe8c:cb00::/24fe8c:cbff:ffff:ffff:ffff:ffff:ffff:ffff
205fe8c:cc00::/24fe8c:ccff:ffff:ffff:ffff:ffff:ffff:ffff
206fe8c:cd00::/24fe8c:cdff:ffff:ffff:ffff:ffff:ffff:ffff
207fe8c:ce00::/24fe8c:ceff:ffff:ffff:ffff:ffff:ffff:ffff
208fe8c:cf00::/24fe8c:cfff:ffff:ffff:ffff:ffff:ffff:ffff
209fe8c:d000::/24fe8c:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
210fe8c:d100::/24fe8c:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
211fe8c:d200::/24fe8c:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
212fe8c:d300::/24fe8c:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
213fe8c:d400::/24fe8c:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
214fe8c:d500::/24fe8c:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
215fe8c:d600::/24fe8c:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
216fe8c:d700::/24fe8c:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
217fe8c:d800::/24fe8c:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
218fe8c:d900::/24fe8c:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
219fe8c:da00::/24fe8c:daff:ffff:ffff:ffff:ffff:ffff:ffff
220fe8c:db00::/24fe8c:dbff:ffff:ffff:ffff:ffff:ffff:ffff
221fe8c:dc00::/24fe8c:dcff:ffff:ffff:ffff:ffff:ffff:ffff
222fe8c:dd00::/24fe8c:ddff:ffff:ffff:ffff:ffff:ffff:ffff
223fe8c:de00::/24fe8c:deff:ffff:ffff:ffff:ffff:ffff:ffff
224fe8c:df00::/24fe8c:dfff:ffff:ffff:ffff:ffff:ffff:ffff
225fe8c:e000::/24fe8c:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
226fe8c:e100::/24fe8c:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
227fe8c:e200::/24fe8c:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
228fe8c:e300::/24fe8c:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
229fe8c:e400::/24fe8c:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
230fe8c:e500::/24fe8c:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
231fe8c:e600::/24fe8c:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
232fe8c:e700::/24fe8c:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
233fe8c:e800::/24fe8c:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
234fe8c:e900::/24fe8c:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
235fe8c:ea00::/24fe8c:eaff:ffff:ffff:ffff:ffff:ffff:ffff
236fe8c:eb00::/24fe8c:ebff:ffff:ffff:ffff:ffff:ffff:ffff
237fe8c:ec00::/24fe8c:ecff:ffff:ffff:ffff:ffff:ffff:ffff
238fe8c:ed00::/24fe8c:edff:ffff:ffff:ffff:ffff:ffff:ffff
239fe8c:ee00::/24fe8c:eeff:ffff:ffff:ffff:ffff:ffff:ffff
240fe8c:ef00::/24fe8c:efff:ffff:ffff:ffff:ffff:ffff:ffff
241fe8c:f000::/24fe8c:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
242fe8c:f100::/24fe8c:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
243fe8c:f200::/24fe8c:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
244fe8c:f300::/24fe8c:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
245fe8c:f400::/24fe8c:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
246fe8c:f500::/24fe8c:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
247fe8c:f600::/24fe8c:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
248fe8c:f700::/24fe8c:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
249fe8c:f800::/24fe8c:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
250fe8c:f900::/24fe8c:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
251fe8c:fa00::/24fe8c:faff:ffff:ffff:ffff:ffff:ffff:ffff
252fe8c:fb00::/24fe8c:fbff:ffff:ffff:ffff:ffff:ffff:ffff
253fe8c:fc00::/24fe8c:fcff:ffff:ffff:ffff:ffff:ffff:ffff
254fe8c:fd00::/24fe8c:fdff:ffff:ffff:ffff:ffff:ffff:ffff
255fe8c:fe00::/24fe8c:feff:ffff:ffff:ffff:ffff:ffff:ffff
256fe8c:ff00::/24fe8c:ffff: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.