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

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

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