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

ffeb::/16 makes 256 subnets of /24.

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