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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
ffba::/16
First address
ffba::
Last address
ffba: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
ffba:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
a.b.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)

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

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