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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/10
Addresses2^118
/64 networks2^54
Network
fe80::/10
First address
fe80::
Last address
febf:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
332,306,998,946,228,968,225,951,765,070,086,144 (2^118)
/64 networks (LANs)
18,014,398,509,481,984 (2^54)
Full form
fe80:0000:0000:0000:0000:0000:0000:0000
Type
Link-local fe80::/10
Every IPv6 interface has one; not routed
Reverse DNS zones
8.e.f.ip6.arpa
9.e.f.ip6.arpa
a.e.f.ip6.arpa
b.e.f.ip6.arpa
/10 is not on a 4-bit boundary, so it takes 4 /12 zones.
Split into smaller subnets/20
/11 (2)/12 (4)/13 (8)/14 (16)/16 (64)/20 (1,024)/24 (16,384)

fe80::/10 makes 1,024 subnets of /20; the first 256 are listed.

Subnets
#SubnetLast address
1fe80::/20fe80:fff:ffff:ffff:ffff:ffff:ffff:ffff
2fe80:1000::/20fe80:1fff:ffff:ffff:ffff:ffff:ffff:ffff
3fe80:2000::/20fe80:2fff:ffff:ffff:ffff:ffff:ffff:ffff
4fe80:3000::/20fe80:3fff:ffff:ffff:ffff:ffff:ffff:ffff
5fe80:4000::/20fe80:4fff:ffff:ffff:ffff:ffff:ffff:ffff
6fe80:5000::/20fe80:5fff:ffff:ffff:ffff:ffff:ffff:ffff
7fe80:6000::/20fe80:6fff:ffff:ffff:ffff:ffff:ffff:ffff
8fe80:7000::/20fe80:7fff:ffff:ffff:ffff:ffff:ffff:ffff
9fe80:8000::/20fe80:8fff:ffff:ffff:ffff:ffff:ffff:ffff
10fe80:9000::/20fe80:9fff:ffff:ffff:ffff:ffff:ffff:ffff
11fe80:a000::/20fe80:afff:ffff:ffff:ffff:ffff:ffff:ffff
12fe80:b000::/20fe80:bfff:ffff:ffff:ffff:ffff:ffff:ffff
13fe80:c000::/20fe80:cfff:ffff:ffff:ffff:ffff:ffff:ffff
14fe80:d000::/20fe80:dfff:ffff:ffff:ffff:ffff:ffff:ffff
15fe80:e000::/20fe80:efff:ffff:ffff:ffff:ffff:ffff:ffff
16fe80:f000::/20fe80:ffff:ffff:ffff:ffff:ffff:ffff:ffff
17fe81::/20fe81:fff:ffff:ffff:ffff:ffff:ffff:ffff
18fe81:1000::/20fe81:1fff:ffff:ffff:ffff:ffff:ffff:ffff
19fe81:2000::/20fe81:2fff:ffff:ffff:ffff:ffff:ffff:ffff
20fe81:3000::/20fe81:3fff:ffff:ffff:ffff:ffff:ffff:ffff
21fe81:4000::/20fe81:4fff:ffff:ffff:ffff:ffff:ffff:ffff
22fe81:5000::/20fe81:5fff:ffff:ffff:ffff:ffff:ffff:ffff
23fe81:6000::/20fe81:6fff:ffff:ffff:ffff:ffff:ffff:ffff
24fe81:7000::/20fe81:7fff:ffff:ffff:ffff:ffff:ffff:ffff
25fe81:8000::/20fe81:8fff:ffff:ffff:ffff:ffff:ffff:ffff
26fe81:9000::/20fe81:9fff:ffff:ffff:ffff:ffff:ffff:ffff
27fe81:a000::/20fe81:afff:ffff:ffff:ffff:ffff:ffff:ffff
28fe81:b000::/20fe81:bfff:ffff:ffff:ffff:ffff:ffff:ffff
29fe81:c000::/20fe81:cfff:ffff:ffff:ffff:ffff:ffff:ffff
30fe81:d000::/20fe81:dfff:ffff:ffff:ffff:ffff:ffff:ffff
31fe81:e000::/20fe81:efff:ffff:ffff:ffff:ffff:ffff:ffff
32fe81:f000::/20fe81:ffff:ffff:ffff:ffff:ffff:ffff:ffff
33fe82::/20fe82:fff:ffff:ffff:ffff:ffff:ffff:ffff
34fe82:1000::/20fe82:1fff:ffff:ffff:ffff:ffff:ffff:ffff
35fe82:2000::/20fe82:2fff:ffff:ffff:ffff:ffff:ffff:ffff
36fe82:3000::/20fe82:3fff:ffff:ffff:ffff:ffff:ffff:ffff
37fe82:4000::/20fe82:4fff:ffff:ffff:ffff:ffff:ffff:ffff
38fe82:5000::/20fe82:5fff:ffff:ffff:ffff:ffff:ffff:ffff
39fe82:6000::/20fe82:6fff:ffff:ffff:ffff:ffff:ffff:ffff
40fe82:7000::/20fe82:7fff:ffff:ffff:ffff:ffff:ffff:ffff
41fe82:8000::/20fe82:8fff:ffff:ffff:ffff:ffff:ffff:ffff
42fe82:9000::/20fe82:9fff:ffff:ffff:ffff:ffff:ffff:ffff
43fe82:a000::/20fe82:afff:ffff:ffff:ffff:ffff:ffff:ffff
44fe82:b000::/20fe82:bfff:ffff:ffff:ffff:ffff:ffff:ffff
45fe82:c000::/20fe82:cfff:ffff:ffff:ffff:ffff:ffff:ffff
46fe82:d000::/20fe82:dfff:ffff:ffff:ffff:ffff:ffff:ffff
47fe82:e000::/20fe82:efff:ffff:ffff:ffff:ffff:ffff:ffff
48fe82:f000::/20fe82:ffff:ffff:ffff:ffff:ffff:ffff:ffff
49fe83::/20fe83:fff:ffff:ffff:ffff:ffff:ffff:ffff
50fe83:1000::/20fe83:1fff:ffff:ffff:ffff:ffff:ffff:ffff
51fe83:2000::/20fe83:2fff:ffff:ffff:ffff:ffff:ffff:ffff
52fe83:3000::/20fe83:3fff:ffff:ffff:ffff:ffff:ffff:ffff
53fe83:4000::/20fe83:4fff:ffff:ffff:ffff:ffff:ffff:ffff
54fe83:5000::/20fe83:5fff:ffff:ffff:ffff:ffff:ffff:ffff
55fe83:6000::/20fe83:6fff:ffff:ffff:ffff:ffff:ffff:ffff
56fe83:7000::/20fe83:7fff:ffff:ffff:ffff:ffff:ffff:ffff
57fe83:8000::/20fe83:8fff:ffff:ffff:ffff:ffff:ffff:ffff
58fe83:9000::/20fe83:9fff:ffff:ffff:ffff:ffff:ffff:ffff
59fe83:a000::/20fe83:afff:ffff:ffff:ffff:ffff:ffff:ffff
60fe83:b000::/20fe83:bfff:ffff:ffff:ffff:ffff:ffff:ffff
61fe83:c000::/20fe83:cfff:ffff:ffff:ffff:ffff:ffff:ffff
62fe83:d000::/20fe83:dfff:ffff:ffff:ffff:ffff:ffff:ffff
63fe83:e000::/20fe83:efff:ffff:ffff:ffff:ffff:ffff:ffff
64fe83:f000::/20fe83:ffff:ffff:ffff:ffff:ffff:ffff:ffff
65fe84::/20fe84:fff:ffff:ffff:ffff:ffff:ffff:ffff
66fe84:1000::/20fe84:1fff:ffff:ffff:ffff:ffff:ffff:ffff
67fe84:2000::/20fe84:2fff:ffff:ffff:ffff:ffff:ffff:ffff
68fe84:3000::/20fe84:3fff:ffff:ffff:ffff:ffff:ffff:ffff
69fe84:4000::/20fe84:4fff:ffff:ffff:ffff:ffff:ffff:ffff
70fe84:5000::/20fe84:5fff:ffff:ffff:ffff:ffff:ffff:ffff
71fe84:6000::/20fe84:6fff:ffff:ffff:ffff:ffff:ffff:ffff
72fe84:7000::/20fe84:7fff:ffff:ffff:ffff:ffff:ffff:ffff
73fe84:8000::/20fe84:8fff:ffff:ffff:ffff:ffff:ffff:ffff
74fe84:9000::/20fe84:9fff:ffff:ffff:ffff:ffff:ffff:ffff
75fe84:a000::/20fe84:afff:ffff:ffff:ffff:ffff:ffff:ffff
76fe84:b000::/20fe84:bfff:ffff:ffff:ffff:ffff:ffff:ffff
77fe84:c000::/20fe84:cfff:ffff:ffff:ffff:ffff:ffff:ffff
78fe84:d000::/20fe84:dfff:ffff:ffff:ffff:ffff:ffff:ffff
79fe84:e000::/20fe84:efff:ffff:ffff:ffff:ffff:ffff:ffff
80fe84:f000::/20fe84:ffff:ffff:ffff:ffff:ffff:ffff:ffff
81fe85::/20fe85:fff:ffff:ffff:ffff:ffff:ffff:ffff
82fe85:1000::/20fe85:1fff:ffff:ffff:ffff:ffff:ffff:ffff
83fe85:2000::/20fe85:2fff:ffff:ffff:ffff:ffff:ffff:ffff
84fe85:3000::/20fe85:3fff:ffff:ffff:ffff:ffff:ffff:ffff
85fe85:4000::/20fe85:4fff:ffff:ffff:ffff:ffff:ffff:ffff
86fe85:5000::/20fe85:5fff:ffff:ffff:ffff:ffff:ffff:ffff
87fe85:6000::/20fe85:6fff:ffff:ffff:ffff:ffff:ffff:ffff
88fe85:7000::/20fe85:7fff:ffff:ffff:ffff:ffff:ffff:ffff
89fe85:8000::/20fe85:8fff:ffff:ffff:ffff:ffff:ffff:ffff
90fe85:9000::/20fe85:9fff:ffff:ffff:ffff:ffff:ffff:ffff
91fe85:a000::/20fe85:afff:ffff:ffff:ffff:ffff:ffff:ffff
92fe85:b000::/20fe85:bfff:ffff:ffff:ffff:ffff:ffff:ffff
93fe85:c000::/20fe85:cfff:ffff:ffff:ffff:ffff:ffff:ffff
94fe85:d000::/20fe85:dfff:ffff:ffff:ffff:ffff:ffff:ffff
95fe85:e000::/20fe85:efff:ffff:ffff:ffff:ffff:ffff:ffff
96fe85:f000::/20fe85:ffff:ffff:ffff:ffff:ffff:ffff:ffff
97fe86::/20fe86:fff:ffff:ffff:ffff:ffff:ffff:ffff
98fe86:1000::/20fe86:1fff:ffff:ffff:ffff:ffff:ffff:ffff
99fe86:2000::/20fe86:2fff:ffff:ffff:ffff:ffff:ffff:ffff
100fe86:3000::/20fe86:3fff:ffff:ffff:ffff:ffff:ffff:ffff
101fe86:4000::/20fe86:4fff:ffff:ffff:ffff:ffff:ffff:ffff
102fe86:5000::/20fe86:5fff:ffff:ffff:ffff:ffff:ffff:ffff
103fe86:6000::/20fe86:6fff:ffff:ffff:ffff:ffff:ffff:ffff
104fe86:7000::/20fe86:7fff:ffff:ffff:ffff:ffff:ffff:ffff
105fe86:8000::/20fe86:8fff:ffff:ffff:ffff:ffff:ffff:ffff
106fe86:9000::/20fe86:9fff:ffff:ffff:ffff:ffff:ffff:ffff
107fe86:a000::/20fe86:afff:ffff:ffff:ffff:ffff:ffff:ffff
108fe86:b000::/20fe86:bfff:ffff:ffff:ffff:ffff:ffff:ffff
109fe86:c000::/20fe86:cfff:ffff:ffff:ffff:ffff:ffff:ffff
110fe86:d000::/20fe86:dfff:ffff:ffff:ffff:ffff:ffff:ffff
111fe86:e000::/20fe86:efff:ffff:ffff:ffff:ffff:ffff:ffff
112fe86:f000::/20fe86:ffff:ffff:ffff:ffff:ffff:ffff:ffff
113fe87::/20fe87:fff:ffff:ffff:ffff:ffff:ffff:ffff
114fe87:1000::/20fe87:1fff:ffff:ffff:ffff:ffff:ffff:ffff
115fe87:2000::/20fe87:2fff:ffff:ffff:ffff:ffff:ffff:ffff
116fe87:3000::/20fe87:3fff:ffff:ffff:ffff:ffff:ffff:ffff
117fe87:4000::/20fe87:4fff:ffff:ffff:ffff:ffff:ffff:ffff
118fe87:5000::/20fe87:5fff:ffff:ffff:ffff:ffff:ffff:ffff
119fe87:6000::/20fe87:6fff:ffff:ffff:ffff:ffff:ffff:ffff
120fe87:7000::/20fe87:7fff:ffff:ffff:ffff:ffff:ffff:ffff
121fe87:8000::/20fe87:8fff:ffff:ffff:ffff:ffff:ffff:ffff
122fe87:9000::/20fe87:9fff:ffff:ffff:ffff:ffff:ffff:ffff
123fe87:a000::/20fe87:afff:ffff:ffff:ffff:ffff:ffff:ffff
124fe87:b000::/20fe87:bfff:ffff:ffff:ffff:ffff:ffff:ffff
125fe87:c000::/20fe87:cfff:ffff:ffff:ffff:ffff:ffff:ffff
126fe87:d000::/20fe87:dfff:ffff:ffff:ffff:ffff:ffff:ffff
127fe87:e000::/20fe87:efff:ffff:ffff:ffff:ffff:ffff:ffff
128fe87:f000::/20fe87:ffff:ffff:ffff:ffff:ffff:ffff:ffff
129fe88::/20fe88:fff:ffff:ffff:ffff:ffff:ffff:ffff
130fe88:1000::/20fe88:1fff:ffff:ffff:ffff:ffff:ffff:ffff
131fe88:2000::/20fe88:2fff:ffff:ffff:ffff:ffff:ffff:ffff
132fe88:3000::/20fe88:3fff:ffff:ffff:ffff:ffff:ffff:ffff
133fe88:4000::/20fe88:4fff:ffff:ffff:ffff:ffff:ffff:ffff
134fe88:5000::/20fe88:5fff:ffff:ffff:ffff:ffff:ffff:ffff
135fe88:6000::/20fe88:6fff:ffff:ffff:ffff:ffff:ffff:ffff
136fe88:7000::/20fe88:7fff:ffff:ffff:ffff:ffff:ffff:ffff
137fe88:8000::/20fe88:8fff:ffff:ffff:ffff:ffff:ffff:ffff
138fe88:9000::/20fe88:9fff:ffff:ffff:ffff:ffff:ffff:ffff
139fe88:a000::/20fe88:afff:ffff:ffff:ffff:ffff:ffff:ffff
140fe88:b000::/20fe88:bfff:ffff:ffff:ffff:ffff:ffff:ffff
141fe88:c000::/20fe88:cfff:ffff:ffff:ffff:ffff:ffff:ffff
142fe88:d000::/20fe88:dfff:ffff:ffff:ffff:ffff:ffff:ffff
143fe88:e000::/20fe88:efff:ffff:ffff:ffff:ffff:ffff:ffff
144fe88:f000::/20fe88:ffff:ffff:ffff:ffff:ffff:ffff:ffff
145fe89::/20fe89:fff:ffff:ffff:ffff:ffff:ffff:ffff
146fe89:1000::/20fe89:1fff:ffff:ffff:ffff:ffff:ffff:ffff
147fe89:2000::/20fe89:2fff:ffff:ffff:ffff:ffff:ffff:ffff
148fe89:3000::/20fe89:3fff:ffff:ffff:ffff:ffff:ffff:ffff
149fe89:4000::/20fe89:4fff:ffff:ffff:ffff:ffff:ffff:ffff
150fe89:5000::/20fe89:5fff:ffff:ffff:ffff:ffff:ffff:ffff
151fe89:6000::/20fe89:6fff:ffff:ffff:ffff:ffff:ffff:ffff
152fe89:7000::/20fe89:7fff:ffff:ffff:ffff:ffff:ffff:ffff
153fe89:8000::/20fe89:8fff:ffff:ffff:ffff:ffff:ffff:ffff
154fe89:9000::/20fe89:9fff:ffff:ffff:ffff:ffff:ffff:ffff
155fe89:a000::/20fe89:afff:ffff:ffff:ffff:ffff:ffff:ffff
156fe89:b000::/20fe89:bfff:ffff:ffff:ffff:ffff:ffff:ffff
157fe89:c000::/20fe89:cfff:ffff:ffff:ffff:ffff:ffff:ffff
158fe89:d000::/20fe89:dfff:ffff:ffff:ffff:ffff:ffff:ffff
159fe89:e000::/20fe89:efff:ffff:ffff:ffff:ffff:ffff:ffff
160fe89:f000::/20fe89:ffff:ffff:ffff:ffff:ffff:ffff:ffff
161fe8a::/20fe8a:fff:ffff:ffff:ffff:ffff:ffff:ffff
162fe8a:1000::/20fe8a:1fff:ffff:ffff:ffff:ffff:ffff:ffff
163fe8a:2000::/20fe8a:2fff:ffff:ffff:ffff:ffff:ffff:ffff
164fe8a:3000::/20fe8a:3fff:ffff:ffff:ffff:ffff:ffff:ffff
165fe8a:4000::/20fe8a:4fff:ffff:ffff:ffff:ffff:ffff:ffff
166fe8a:5000::/20fe8a:5fff:ffff:ffff:ffff:ffff:ffff:ffff
167fe8a:6000::/20fe8a:6fff:ffff:ffff:ffff:ffff:ffff:ffff
168fe8a:7000::/20fe8a:7fff:ffff:ffff:ffff:ffff:ffff:ffff
169fe8a:8000::/20fe8a:8fff:ffff:ffff:ffff:ffff:ffff:ffff
170fe8a:9000::/20fe8a:9fff:ffff:ffff:ffff:ffff:ffff:ffff
171fe8a:a000::/20fe8a:afff:ffff:ffff:ffff:ffff:ffff:ffff
172fe8a:b000::/20fe8a:bfff:ffff:ffff:ffff:ffff:ffff:ffff
173fe8a:c000::/20fe8a:cfff:ffff:ffff:ffff:ffff:ffff:ffff
174fe8a:d000::/20fe8a:dfff:ffff:ffff:ffff:ffff:ffff:ffff
175fe8a:e000::/20fe8a:efff:ffff:ffff:ffff:ffff:ffff:ffff
176fe8a:f000::/20fe8a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
177fe8b::/20fe8b:fff:ffff:ffff:ffff:ffff:ffff:ffff
178fe8b:1000::/20fe8b:1fff:ffff:ffff:ffff:ffff:ffff:ffff
179fe8b:2000::/20fe8b:2fff:ffff:ffff:ffff:ffff:ffff:ffff
180fe8b:3000::/20fe8b:3fff:ffff:ffff:ffff:ffff:ffff:ffff
181fe8b:4000::/20fe8b:4fff:ffff:ffff:ffff:ffff:ffff:ffff
182fe8b:5000::/20fe8b:5fff:ffff:ffff:ffff:ffff:ffff:ffff
183fe8b:6000::/20fe8b:6fff:ffff:ffff:ffff:ffff:ffff:ffff
184fe8b:7000::/20fe8b:7fff:ffff:ffff:ffff:ffff:ffff:ffff
185fe8b:8000::/20fe8b:8fff:ffff:ffff:ffff:ffff:ffff:ffff
186fe8b:9000::/20fe8b:9fff:ffff:ffff:ffff:ffff:ffff:ffff
187fe8b:a000::/20fe8b:afff:ffff:ffff:ffff:ffff:ffff:ffff
188fe8b:b000::/20fe8b:bfff:ffff:ffff:ffff:ffff:ffff:ffff
189fe8b:c000::/20fe8b:cfff:ffff:ffff:ffff:ffff:ffff:ffff
190fe8b:d000::/20fe8b:dfff:ffff:ffff:ffff:ffff:ffff:ffff
191fe8b:e000::/20fe8b:efff:ffff:ffff:ffff:ffff:ffff:ffff
192fe8b:f000::/20fe8b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
193fe8c::/20fe8c:fff:ffff:ffff:ffff:ffff:ffff:ffff
194fe8c:1000::/20fe8c:1fff:ffff:ffff:ffff:ffff:ffff:ffff
195fe8c:2000::/20fe8c:2fff:ffff:ffff:ffff:ffff:ffff:ffff
196fe8c:3000::/20fe8c:3fff:ffff:ffff:ffff:ffff:ffff:ffff
197fe8c:4000::/20fe8c:4fff:ffff:ffff:ffff:ffff:ffff:ffff
198fe8c:5000::/20fe8c:5fff:ffff:ffff:ffff:ffff:ffff:ffff
199fe8c:6000::/20fe8c:6fff:ffff:ffff:ffff:ffff:ffff:ffff
200fe8c:7000::/20fe8c:7fff:ffff:ffff:ffff:ffff:ffff:ffff
201fe8c:8000::/20fe8c:8fff:ffff:ffff:ffff:ffff:ffff:ffff
202fe8c:9000::/20fe8c:9fff:ffff:ffff:ffff:ffff:ffff:ffff
203fe8c:a000::/20fe8c:afff:ffff:ffff:ffff:ffff:ffff:ffff
204fe8c:b000::/20fe8c:bfff:ffff:ffff:ffff:ffff:ffff:ffff
205fe8c:c000::/20fe8c:cfff:ffff:ffff:ffff:ffff:ffff:ffff
206fe8c:d000::/20fe8c:dfff:ffff:ffff:ffff:ffff:ffff:ffff
207fe8c:e000::/20fe8c:efff:ffff:ffff:ffff:ffff:ffff:ffff
208fe8c:f000::/20fe8c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
209fe8d::/20fe8d:fff:ffff:ffff:ffff:ffff:ffff:ffff
210fe8d:1000::/20fe8d:1fff:ffff:ffff:ffff:ffff:ffff:ffff
211fe8d:2000::/20fe8d:2fff:ffff:ffff:ffff:ffff:ffff:ffff
212fe8d:3000::/20fe8d:3fff:ffff:ffff:ffff:ffff:ffff:ffff
213fe8d:4000::/20fe8d:4fff:ffff:ffff:ffff:ffff:ffff:ffff
214fe8d:5000::/20fe8d:5fff:ffff:ffff:ffff:ffff:ffff:ffff
215fe8d:6000::/20fe8d:6fff:ffff:ffff:ffff:ffff:ffff:ffff
216fe8d:7000::/20fe8d:7fff:ffff:ffff:ffff:ffff:ffff:ffff
217fe8d:8000::/20fe8d:8fff:ffff:ffff:ffff:ffff:ffff:ffff
218fe8d:9000::/20fe8d:9fff:ffff:ffff:ffff:ffff:ffff:ffff
219fe8d:a000::/20fe8d:afff:ffff:ffff:ffff:ffff:ffff:ffff
220fe8d:b000::/20fe8d:bfff:ffff:ffff:ffff:ffff:ffff:ffff
221fe8d:c000::/20fe8d:cfff:ffff:ffff:ffff:ffff:ffff:ffff
222fe8d:d000::/20fe8d:dfff:ffff:ffff:ffff:ffff:ffff:ffff
223fe8d:e000::/20fe8d:efff:ffff:ffff:ffff:ffff:ffff:ffff
224fe8d:f000::/20fe8d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
225fe8e::/20fe8e:fff:ffff:ffff:ffff:ffff:ffff:ffff
226fe8e:1000::/20fe8e:1fff:ffff:ffff:ffff:ffff:ffff:ffff
227fe8e:2000::/20fe8e:2fff:ffff:ffff:ffff:ffff:ffff:ffff
228fe8e:3000::/20fe8e:3fff:ffff:ffff:ffff:ffff:ffff:ffff
229fe8e:4000::/20fe8e:4fff:ffff:ffff:ffff:ffff:ffff:ffff
230fe8e:5000::/20fe8e:5fff:ffff:ffff:ffff:ffff:ffff:ffff
231fe8e:6000::/20fe8e:6fff:ffff:ffff:ffff:ffff:ffff:ffff
232fe8e:7000::/20fe8e:7fff:ffff:ffff:ffff:ffff:ffff:ffff
233fe8e:8000::/20fe8e:8fff:ffff:ffff:ffff:ffff:ffff:ffff
234fe8e:9000::/20fe8e:9fff:ffff:ffff:ffff:ffff:ffff:ffff
235fe8e:a000::/20fe8e:afff:ffff:ffff:ffff:ffff:ffff:ffff
236fe8e:b000::/20fe8e:bfff:ffff:ffff:ffff:ffff:ffff:ffff
237fe8e:c000::/20fe8e:cfff:ffff:ffff:ffff:ffff:ffff:ffff
238fe8e:d000::/20fe8e:dfff:ffff:ffff:ffff:ffff:ffff:ffff
239fe8e:e000::/20fe8e:efff:ffff:ffff:ffff:ffff:ffff:ffff
240fe8e:f000::/20fe8e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
241fe8f::/20fe8f:fff:ffff:ffff:ffff:ffff:ffff:ffff
242fe8f:1000::/20fe8f:1fff:ffff:ffff:ffff:ffff:ffff:ffff
243fe8f:2000::/20fe8f:2fff:ffff:ffff:ffff:ffff:ffff:ffff
244fe8f:3000::/20fe8f:3fff:ffff:ffff:ffff:ffff:ffff:ffff
245fe8f:4000::/20fe8f:4fff:ffff:ffff:ffff:ffff:ffff:ffff
246fe8f:5000::/20fe8f:5fff:ffff:ffff:ffff:ffff:ffff:ffff
247fe8f:6000::/20fe8f:6fff:ffff:ffff:ffff:ffff:ffff:ffff
248fe8f:7000::/20fe8f:7fff:ffff:ffff:ffff:ffff:ffff:ffff
249fe8f:8000::/20fe8f:8fff:ffff:ffff:ffff:ffff:ffff:ffff
250fe8f:9000::/20fe8f:9fff:ffff:ffff:ffff:ffff:ffff:ffff
251fe8f:a000::/20fe8f:afff:ffff:ffff:ffff:ffff:ffff:ffff
252fe8f:b000::/20fe8f:bfff:ffff:ffff:ffff:ffff:ffff:ffff
253fe8f:c000::/20fe8f:cfff:ffff:ffff:ffff:ffff:ffff:ffff
254fe8f:d000::/20fe8f:dfff:ffff:ffff:ffff:ffff:ffff:ffff
255fe8f:e000::/20fe8f:efff:ffff:ffff:ffff:ffff:ffff:ffff
256fe8f:f000::/20fe8f: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.