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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/20
Addresses2^108
/64 networks2^44
Network
fe84:c000::/20
First address
fe84:c000::
Last address
fe84:cfff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
324,518,553,658,426,726,783,156,020,576,256 (2^108)
/64 networks (LANs)
17,592,186,044,416 (2^44)
Full form
fe84:c000:0000:0000:0000:0000:0000:0000
Type
Link-local fe80::/10
Every IPv6 interface has one; not routed
Reverse DNS zone
c.4.8.e.f.ip6.arpa
Split into smaller subnets/32
/21 (2)/22 (4)/23 (8)/24 (16)/28 (256)/32 (4,096)/36 (65,536)

fe84:c000::/20 makes 4,096 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
1fe84:c000::/32fe84:c000:ffff:ffff:ffff:ffff:ffff:ffff
2fe84:c001::/32fe84:c001:ffff:ffff:ffff:ffff:ffff:ffff
3fe84:c002::/32fe84:c002:ffff:ffff:ffff:ffff:ffff:ffff
4fe84:c003::/32fe84:c003:ffff:ffff:ffff:ffff:ffff:ffff
5fe84:c004::/32fe84:c004:ffff:ffff:ffff:ffff:ffff:ffff
6fe84:c005::/32fe84:c005:ffff:ffff:ffff:ffff:ffff:ffff
7fe84:c006::/32fe84:c006:ffff:ffff:ffff:ffff:ffff:ffff
8fe84:c007::/32fe84:c007:ffff:ffff:ffff:ffff:ffff:ffff
9fe84:c008::/32fe84:c008:ffff:ffff:ffff:ffff:ffff:ffff
10fe84:c009::/32fe84:c009:ffff:ffff:ffff:ffff:ffff:ffff
11fe84:c00a::/32fe84:c00a:ffff:ffff:ffff:ffff:ffff:ffff
12fe84:c00b::/32fe84:c00b:ffff:ffff:ffff:ffff:ffff:ffff
13fe84:c00c::/32fe84:c00c:ffff:ffff:ffff:ffff:ffff:ffff
14fe84:c00d::/32fe84:c00d:ffff:ffff:ffff:ffff:ffff:ffff
15fe84:c00e::/32fe84:c00e:ffff:ffff:ffff:ffff:ffff:ffff
16fe84:c00f::/32fe84:c00f:ffff:ffff:ffff:ffff:ffff:ffff
17fe84:c010::/32fe84:c010:ffff:ffff:ffff:ffff:ffff:ffff
18fe84:c011::/32fe84:c011:ffff:ffff:ffff:ffff:ffff:ffff
19fe84:c012::/32fe84:c012:ffff:ffff:ffff:ffff:ffff:ffff
20fe84:c013::/32fe84:c013:ffff:ffff:ffff:ffff:ffff:ffff
21fe84:c014::/32fe84:c014:ffff:ffff:ffff:ffff:ffff:ffff
22fe84:c015::/32fe84:c015:ffff:ffff:ffff:ffff:ffff:ffff
23fe84:c016::/32fe84:c016:ffff:ffff:ffff:ffff:ffff:ffff
24fe84:c017::/32fe84:c017:ffff:ffff:ffff:ffff:ffff:ffff
25fe84:c018::/32fe84:c018:ffff:ffff:ffff:ffff:ffff:ffff
26fe84:c019::/32fe84:c019:ffff:ffff:ffff:ffff:ffff:ffff
27fe84:c01a::/32fe84:c01a:ffff:ffff:ffff:ffff:ffff:ffff
28fe84:c01b::/32fe84:c01b:ffff:ffff:ffff:ffff:ffff:ffff
29fe84:c01c::/32fe84:c01c:ffff:ffff:ffff:ffff:ffff:ffff
30fe84:c01d::/32fe84:c01d:ffff:ffff:ffff:ffff:ffff:ffff
31fe84:c01e::/32fe84:c01e:ffff:ffff:ffff:ffff:ffff:ffff
32fe84:c01f::/32fe84:c01f:ffff:ffff:ffff:ffff:ffff:ffff
33fe84:c020::/32fe84:c020:ffff:ffff:ffff:ffff:ffff:ffff
34fe84:c021::/32fe84:c021:ffff:ffff:ffff:ffff:ffff:ffff
35fe84:c022::/32fe84:c022:ffff:ffff:ffff:ffff:ffff:ffff
36fe84:c023::/32fe84:c023:ffff:ffff:ffff:ffff:ffff:ffff
37fe84:c024::/32fe84:c024:ffff:ffff:ffff:ffff:ffff:ffff
38fe84:c025::/32fe84:c025:ffff:ffff:ffff:ffff:ffff:ffff
39fe84:c026::/32fe84:c026:ffff:ffff:ffff:ffff:ffff:ffff
40fe84:c027::/32fe84:c027:ffff:ffff:ffff:ffff:ffff:ffff
41fe84:c028::/32fe84:c028:ffff:ffff:ffff:ffff:ffff:ffff
42fe84:c029::/32fe84:c029:ffff:ffff:ffff:ffff:ffff:ffff
43fe84:c02a::/32fe84:c02a:ffff:ffff:ffff:ffff:ffff:ffff
44fe84:c02b::/32fe84:c02b:ffff:ffff:ffff:ffff:ffff:ffff
45fe84:c02c::/32fe84:c02c:ffff:ffff:ffff:ffff:ffff:ffff
46fe84:c02d::/32fe84:c02d:ffff:ffff:ffff:ffff:ffff:ffff
47fe84:c02e::/32fe84:c02e:ffff:ffff:ffff:ffff:ffff:ffff
48fe84:c02f::/32fe84:c02f:ffff:ffff:ffff:ffff:ffff:ffff
49fe84:c030::/32fe84:c030:ffff:ffff:ffff:ffff:ffff:ffff
50fe84:c031::/32fe84:c031:ffff:ffff:ffff:ffff:ffff:ffff
51fe84:c032::/32fe84:c032:ffff:ffff:ffff:ffff:ffff:ffff
52fe84:c033::/32fe84:c033:ffff:ffff:ffff:ffff:ffff:ffff
53fe84:c034::/32fe84:c034:ffff:ffff:ffff:ffff:ffff:ffff
54fe84:c035::/32fe84:c035:ffff:ffff:ffff:ffff:ffff:ffff
55fe84:c036::/32fe84:c036:ffff:ffff:ffff:ffff:ffff:ffff
56fe84:c037::/32fe84:c037:ffff:ffff:ffff:ffff:ffff:ffff
57fe84:c038::/32fe84:c038:ffff:ffff:ffff:ffff:ffff:ffff
58fe84:c039::/32fe84:c039:ffff:ffff:ffff:ffff:ffff:ffff
59fe84:c03a::/32fe84:c03a:ffff:ffff:ffff:ffff:ffff:ffff
60fe84:c03b::/32fe84:c03b:ffff:ffff:ffff:ffff:ffff:ffff
61fe84:c03c::/32fe84:c03c:ffff:ffff:ffff:ffff:ffff:ffff
62fe84:c03d::/32fe84:c03d:ffff:ffff:ffff:ffff:ffff:ffff
63fe84:c03e::/32fe84:c03e:ffff:ffff:ffff:ffff:ffff:ffff
64fe84:c03f::/32fe84:c03f:ffff:ffff:ffff:ffff:ffff:ffff
65fe84:c040::/32fe84:c040:ffff:ffff:ffff:ffff:ffff:ffff
66fe84:c041::/32fe84:c041:ffff:ffff:ffff:ffff:ffff:ffff
67fe84:c042::/32fe84:c042:ffff:ffff:ffff:ffff:ffff:ffff
68fe84:c043::/32fe84:c043:ffff:ffff:ffff:ffff:ffff:ffff
69fe84:c044::/32fe84:c044:ffff:ffff:ffff:ffff:ffff:ffff
70fe84:c045::/32fe84:c045:ffff:ffff:ffff:ffff:ffff:ffff
71fe84:c046::/32fe84:c046:ffff:ffff:ffff:ffff:ffff:ffff
72fe84:c047::/32fe84:c047:ffff:ffff:ffff:ffff:ffff:ffff
73fe84:c048::/32fe84:c048:ffff:ffff:ffff:ffff:ffff:ffff
74fe84:c049::/32fe84:c049:ffff:ffff:ffff:ffff:ffff:ffff
75fe84:c04a::/32fe84:c04a:ffff:ffff:ffff:ffff:ffff:ffff
76fe84:c04b::/32fe84:c04b:ffff:ffff:ffff:ffff:ffff:ffff
77fe84:c04c::/32fe84:c04c:ffff:ffff:ffff:ffff:ffff:ffff
78fe84:c04d::/32fe84:c04d:ffff:ffff:ffff:ffff:ffff:ffff
79fe84:c04e::/32fe84:c04e:ffff:ffff:ffff:ffff:ffff:ffff
80fe84:c04f::/32fe84:c04f:ffff:ffff:ffff:ffff:ffff:ffff
81fe84:c050::/32fe84:c050:ffff:ffff:ffff:ffff:ffff:ffff
82fe84:c051::/32fe84:c051:ffff:ffff:ffff:ffff:ffff:ffff
83fe84:c052::/32fe84:c052:ffff:ffff:ffff:ffff:ffff:ffff
84fe84:c053::/32fe84:c053:ffff:ffff:ffff:ffff:ffff:ffff
85fe84:c054::/32fe84:c054:ffff:ffff:ffff:ffff:ffff:ffff
86fe84:c055::/32fe84:c055:ffff:ffff:ffff:ffff:ffff:ffff
87fe84:c056::/32fe84:c056:ffff:ffff:ffff:ffff:ffff:ffff
88fe84:c057::/32fe84:c057:ffff:ffff:ffff:ffff:ffff:ffff
89fe84:c058::/32fe84:c058:ffff:ffff:ffff:ffff:ffff:ffff
90fe84:c059::/32fe84:c059:ffff:ffff:ffff:ffff:ffff:ffff
91fe84:c05a::/32fe84:c05a:ffff:ffff:ffff:ffff:ffff:ffff
92fe84:c05b::/32fe84:c05b:ffff:ffff:ffff:ffff:ffff:ffff
93fe84:c05c::/32fe84:c05c:ffff:ffff:ffff:ffff:ffff:ffff
94fe84:c05d::/32fe84:c05d:ffff:ffff:ffff:ffff:ffff:ffff
95fe84:c05e::/32fe84:c05e:ffff:ffff:ffff:ffff:ffff:ffff
96fe84:c05f::/32fe84:c05f:ffff:ffff:ffff:ffff:ffff:ffff
97fe84:c060::/32fe84:c060:ffff:ffff:ffff:ffff:ffff:ffff
98fe84:c061::/32fe84:c061:ffff:ffff:ffff:ffff:ffff:ffff
99fe84:c062::/32fe84:c062:ffff:ffff:ffff:ffff:ffff:ffff
100fe84:c063::/32fe84:c063:ffff:ffff:ffff:ffff:ffff:ffff
101fe84:c064::/32fe84:c064:ffff:ffff:ffff:ffff:ffff:ffff
102fe84:c065::/32fe84:c065:ffff:ffff:ffff:ffff:ffff:ffff
103fe84:c066::/32fe84:c066:ffff:ffff:ffff:ffff:ffff:ffff
104fe84:c067::/32fe84:c067:ffff:ffff:ffff:ffff:ffff:ffff
105fe84:c068::/32fe84:c068:ffff:ffff:ffff:ffff:ffff:ffff
106fe84:c069::/32fe84:c069:ffff:ffff:ffff:ffff:ffff:ffff
107fe84:c06a::/32fe84:c06a:ffff:ffff:ffff:ffff:ffff:ffff
108fe84:c06b::/32fe84:c06b:ffff:ffff:ffff:ffff:ffff:ffff
109fe84:c06c::/32fe84:c06c:ffff:ffff:ffff:ffff:ffff:ffff
110fe84:c06d::/32fe84:c06d:ffff:ffff:ffff:ffff:ffff:ffff
111fe84:c06e::/32fe84:c06e:ffff:ffff:ffff:ffff:ffff:ffff
112fe84:c06f::/32fe84:c06f:ffff:ffff:ffff:ffff:ffff:ffff
113fe84:c070::/32fe84:c070:ffff:ffff:ffff:ffff:ffff:ffff
114fe84:c071::/32fe84:c071:ffff:ffff:ffff:ffff:ffff:ffff
115fe84:c072::/32fe84:c072:ffff:ffff:ffff:ffff:ffff:ffff
116fe84:c073::/32fe84:c073:ffff:ffff:ffff:ffff:ffff:ffff
117fe84:c074::/32fe84:c074:ffff:ffff:ffff:ffff:ffff:ffff
118fe84:c075::/32fe84:c075:ffff:ffff:ffff:ffff:ffff:ffff
119fe84:c076::/32fe84:c076:ffff:ffff:ffff:ffff:ffff:ffff
120fe84:c077::/32fe84:c077:ffff:ffff:ffff:ffff:ffff:ffff
121fe84:c078::/32fe84:c078:ffff:ffff:ffff:ffff:ffff:ffff
122fe84:c079::/32fe84:c079:ffff:ffff:ffff:ffff:ffff:ffff
123fe84:c07a::/32fe84:c07a:ffff:ffff:ffff:ffff:ffff:ffff
124fe84:c07b::/32fe84:c07b:ffff:ffff:ffff:ffff:ffff:ffff
125fe84:c07c::/32fe84:c07c:ffff:ffff:ffff:ffff:ffff:ffff
126fe84:c07d::/32fe84:c07d:ffff:ffff:ffff:ffff:ffff:ffff
127fe84:c07e::/32fe84:c07e:ffff:ffff:ffff:ffff:ffff:ffff
128fe84:c07f::/32fe84:c07f:ffff:ffff:ffff:ffff:ffff:ffff
129fe84:c080::/32fe84:c080:ffff:ffff:ffff:ffff:ffff:ffff
130fe84:c081::/32fe84:c081:ffff:ffff:ffff:ffff:ffff:ffff
131fe84:c082::/32fe84:c082:ffff:ffff:ffff:ffff:ffff:ffff
132fe84:c083::/32fe84:c083:ffff:ffff:ffff:ffff:ffff:ffff
133fe84:c084::/32fe84:c084:ffff:ffff:ffff:ffff:ffff:ffff
134fe84:c085::/32fe84:c085:ffff:ffff:ffff:ffff:ffff:ffff
135fe84:c086::/32fe84:c086:ffff:ffff:ffff:ffff:ffff:ffff
136fe84:c087::/32fe84:c087:ffff:ffff:ffff:ffff:ffff:ffff
137fe84:c088::/32fe84:c088:ffff:ffff:ffff:ffff:ffff:ffff
138fe84:c089::/32fe84:c089:ffff:ffff:ffff:ffff:ffff:ffff
139fe84:c08a::/32fe84:c08a:ffff:ffff:ffff:ffff:ffff:ffff
140fe84:c08b::/32fe84:c08b:ffff:ffff:ffff:ffff:ffff:ffff
141fe84:c08c::/32fe84:c08c:ffff:ffff:ffff:ffff:ffff:ffff
142fe84:c08d::/32fe84:c08d:ffff:ffff:ffff:ffff:ffff:ffff
143fe84:c08e::/32fe84:c08e:ffff:ffff:ffff:ffff:ffff:ffff
144fe84:c08f::/32fe84:c08f:ffff:ffff:ffff:ffff:ffff:ffff
145fe84:c090::/32fe84:c090:ffff:ffff:ffff:ffff:ffff:ffff
146fe84:c091::/32fe84:c091:ffff:ffff:ffff:ffff:ffff:ffff
147fe84:c092::/32fe84:c092:ffff:ffff:ffff:ffff:ffff:ffff
148fe84:c093::/32fe84:c093:ffff:ffff:ffff:ffff:ffff:ffff
149fe84:c094::/32fe84:c094:ffff:ffff:ffff:ffff:ffff:ffff
150fe84:c095::/32fe84:c095:ffff:ffff:ffff:ffff:ffff:ffff
151fe84:c096::/32fe84:c096:ffff:ffff:ffff:ffff:ffff:ffff
152fe84:c097::/32fe84:c097:ffff:ffff:ffff:ffff:ffff:ffff
153fe84:c098::/32fe84:c098:ffff:ffff:ffff:ffff:ffff:ffff
154fe84:c099::/32fe84:c099:ffff:ffff:ffff:ffff:ffff:ffff
155fe84:c09a::/32fe84:c09a:ffff:ffff:ffff:ffff:ffff:ffff
156fe84:c09b::/32fe84:c09b:ffff:ffff:ffff:ffff:ffff:ffff
157fe84:c09c::/32fe84:c09c:ffff:ffff:ffff:ffff:ffff:ffff
158fe84:c09d::/32fe84:c09d:ffff:ffff:ffff:ffff:ffff:ffff
159fe84:c09e::/32fe84:c09e:ffff:ffff:ffff:ffff:ffff:ffff
160fe84:c09f::/32fe84:c09f:ffff:ffff:ffff:ffff:ffff:ffff
161fe84:c0a0::/32fe84:c0a0:ffff:ffff:ffff:ffff:ffff:ffff
162fe84:c0a1::/32fe84:c0a1:ffff:ffff:ffff:ffff:ffff:ffff
163fe84:c0a2::/32fe84:c0a2:ffff:ffff:ffff:ffff:ffff:ffff
164fe84:c0a3::/32fe84:c0a3:ffff:ffff:ffff:ffff:ffff:ffff
165fe84:c0a4::/32fe84:c0a4:ffff:ffff:ffff:ffff:ffff:ffff
166fe84:c0a5::/32fe84:c0a5:ffff:ffff:ffff:ffff:ffff:ffff
167fe84:c0a6::/32fe84:c0a6:ffff:ffff:ffff:ffff:ffff:ffff
168fe84:c0a7::/32fe84:c0a7:ffff:ffff:ffff:ffff:ffff:ffff
169fe84:c0a8::/32fe84:c0a8:ffff:ffff:ffff:ffff:ffff:ffff
170fe84:c0a9::/32fe84:c0a9:ffff:ffff:ffff:ffff:ffff:ffff
171fe84:c0aa::/32fe84:c0aa:ffff:ffff:ffff:ffff:ffff:ffff
172fe84:c0ab::/32fe84:c0ab:ffff:ffff:ffff:ffff:ffff:ffff
173fe84:c0ac::/32fe84:c0ac:ffff:ffff:ffff:ffff:ffff:ffff
174fe84:c0ad::/32fe84:c0ad:ffff:ffff:ffff:ffff:ffff:ffff
175fe84:c0ae::/32fe84:c0ae:ffff:ffff:ffff:ffff:ffff:ffff
176fe84:c0af::/32fe84:c0af:ffff:ffff:ffff:ffff:ffff:ffff
177fe84:c0b0::/32fe84:c0b0:ffff:ffff:ffff:ffff:ffff:ffff
178fe84:c0b1::/32fe84:c0b1:ffff:ffff:ffff:ffff:ffff:ffff
179fe84:c0b2::/32fe84:c0b2:ffff:ffff:ffff:ffff:ffff:ffff
180fe84:c0b3::/32fe84:c0b3:ffff:ffff:ffff:ffff:ffff:ffff
181fe84:c0b4::/32fe84:c0b4:ffff:ffff:ffff:ffff:ffff:ffff
182fe84:c0b5::/32fe84:c0b5:ffff:ffff:ffff:ffff:ffff:ffff
183fe84:c0b6::/32fe84:c0b6:ffff:ffff:ffff:ffff:ffff:ffff
184fe84:c0b7::/32fe84:c0b7:ffff:ffff:ffff:ffff:ffff:ffff
185fe84:c0b8::/32fe84:c0b8:ffff:ffff:ffff:ffff:ffff:ffff
186fe84:c0b9::/32fe84:c0b9:ffff:ffff:ffff:ffff:ffff:ffff
187fe84:c0ba::/32fe84:c0ba:ffff:ffff:ffff:ffff:ffff:ffff
188fe84:c0bb::/32fe84:c0bb:ffff:ffff:ffff:ffff:ffff:ffff
189fe84:c0bc::/32fe84:c0bc:ffff:ffff:ffff:ffff:ffff:ffff
190fe84:c0bd::/32fe84:c0bd:ffff:ffff:ffff:ffff:ffff:ffff
191fe84:c0be::/32fe84:c0be:ffff:ffff:ffff:ffff:ffff:ffff
192fe84:c0bf::/32fe84:c0bf:ffff:ffff:ffff:ffff:ffff:ffff
193fe84:c0c0::/32fe84:c0c0:ffff:ffff:ffff:ffff:ffff:ffff
194fe84:c0c1::/32fe84:c0c1:ffff:ffff:ffff:ffff:ffff:ffff
195fe84:c0c2::/32fe84:c0c2:ffff:ffff:ffff:ffff:ffff:ffff
196fe84:c0c3::/32fe84:c0c3:ffff:ffff:ffff:ffff:ffff:ffff
197fe84:c0c4::/32fe84:c0c4:ffff:ffff:ffff:ffff:ffff:ffff
198fe84:c0c5::/32fe84:c0c5:ffff:ffff:ffff:ffff:ffff:ffff
199fe84:c0c6::/32fe84:c0c6:ffff:ffff:ffff:ffff:ffff:ffff
200fe84:c0c7::/32fe84:c0c7:ffff:ffff:ffff:ffff:ffff:ffff
201fe84:c0c8::/32fe84:c0c8:ffff:ffff:ffff:ffff:ffff:ffff
202fe84:c0c9::/32fe84:c0c9:ffff:ffff:ffff:ffff:ffff:ffff
203fe84:c0ca::/32fe84:c0ca:ffff:ffff:ffff:ffff:ffff:ffff
204fe84:c0cb::/32fe84:c0cb:ffff:ffff:ffff:ffff:ffff:ffff
205fe84:c0cc::/32fe84:c0cc:ffff:ffff:ffff:ffff:ffff:ffff
206fe84:c0cd::/32fe84:c0cd:ffff:ffff:ffff:ffff:ffff:ffff
207fe84:c0ce::/32fe84:c0ce:ffff:ffff:ffff:ffff:ffff:ffff
208fe84:c0cf::/32fe84:c0cf:ffff:ffff:ffff:ffff:ffff:ffff
209fe84:c0d0::/32fe84:c0d0:ffff:ffff:ffff:ffff:ffff:ffff
210fe84:c0d1::/32fe84:c0d1:ffff:ffff:ffff:ffff:ffff:ffff
211fe84:c0d2::/32fe84:c0d2:ffff:ffff:ffff:ffff:ffff:ffff
212fe84:c0d3::/32fe84:c0d3:ffff:ffff:ffff:ffff:ffff:ffff
213fe84:c0d4::/32fe84:c0d4:ffff:ffff:ffff:ffff:ffff:ffff
214fe84:c0d5::/32fe84:c0d5:ffff:ffff:ffff:ffff:ffff:ffff
215fe84:c0d6::/32fe84:c0d6:ffff:ffff:ffff:ffff:ffff:ffff
216fe84:c0d7::/32fe84:c0d7:ffff:ffff:ffff:ffff:ffff:ffff
217fe84:c0d8::/32fe84:c0d8:ffff:ffff:ffff:ffff:ffff:ffff
218fe84:c0d9::/32fe84:c0d9:ffff:ffff:ffff:ffff:ffff:ffff
219fe84:c0da::/32fe84:c0da:ffff:ffff:ffff:ffff:ffff:ffff
220fe84:c0db::/32fe84:c0db:ffff:ffff:ffff:ffff:ffff:ffff
221fe84:c0dc::/32fe84:c0dc:ffff:ffff:ffff:ffff:ffff:ffff
222fe84:c0dd::/32fe84:c0dd:ffff:ffff:ffff:ffff:ffff:ffff
223fe84:c0de::/32fe84:c0de:ffff:ffff:ffff:ffff:ffff:ffff
224fe84:c0df::/32fe84:c0df:ffff:ffff:ffff:ffff:ffff:ffff
225fe84:c0e0::/32fe84:c0e0:ffff:ffff:ffff:ffff:ffff:ffff
226fe84:c0e1::/32fe84:c0e1:ffff:ffff:ffff:ffff:ffff:ffff
227fe84:c0e2::/32fe84:c0e2:ffff:ffff:ffff:ffff:ffff:ffff
228fe84:c0e3::/32fe84:c0e3:ffff:ffff:ffff:ffff:ffff:ffff
229fe84:c0e4::/32fe84:c0e4:ffff:ffff:ffff:ffff:ffff:ffff
230fe84:c0e5::/32fe84:c0e5:ffff:ffff:ffff:ffff:ffff:ffff
231fe84:c0e6::/32fe84:c0e6:ffff:ffff:ffff:ffff:ffff:ffff
232fe84:c0e7::/32fe84:c0e7:ffff:ffff:ffff:ffff:ffff:ffff
233fe84:c0e8::/32fe84:c0e8:ffff:ffff:ffff:ffff:ffff:ffff
234fe84:c0e9::/32fe84:c0e9:ffff:ffff:ffff:ffff:ffff:ffff
235fe84:c0ea::/32fe84:c0ea:ffff:ffff:ffff:ffff:ffff:ffff
236fe84:c0eb::/32fe84:c0eb:ffff:ffff:ffff:ffff:ffff:ffff
237fe84:c0ec::/32fe84:c0ec:ffff:ffff:ffff:ffff:ffff:ffff
238fe84:c0ed::/32fe84:c0ed:ffff:ffff:ffff:ffff:ffff:ffff
239fe84:c0ee::/32fe84:c0ee:ffff:ffff:ffff:ffff:ffff:ffff
240fe84:c0ef::/32fe84:c0ef:ffff:ffff:ffff:ffff:ffff:ffff
241fe84:c0f0::/32fe84:c0f0:ffff:ffff:ffff:ffff:ffff:ffff
242fe84:c0f1::/32fe84:c0f1:ffff:ffff:ffff:ffff:ffff:ffff
243fe84:c0f2::/32fe84:c0f2:ffff:ffff:ffff:ffff:ffff:ffff
244fe84:c0f3::/32fe84:c0f3:ffff:ffff:ffff:ffff:ffff:ffff
245fe84:c0f4::/32fe84:c0f4:ffff:ffff:ffff:ffff:ffff:ffff
246fe84:c0f5::/32fe84:c0f5:ffff:ffff:ffff:ffff:ffff:ffff
247fe84:c0f6::/32fe84:c0f6:ffff:ffff:ffff:ffff:ffff:ffff
248fe84:c0f7::/32fe84:c0f7:ffff:ffff:ffff:ffff:ffff:ffff
249fe84:c0f8::/32fe84:c0f8:ffff:ffff:ffff:ffff:ffff:ffff
250fe84:c0f9::/32fe84:c0f9:ffff:ffff:ffff:ffff:ffff:ffff
251fe84:c0fa::/32fe84:c0fa:ffff:ffff:ffff:ffff:ffff:ffff
252fe84:c0fb::/32fe84:c0fb:ffff:ffff:ffff:ffff:ffff:ffff
253fe84:c0fc::/32fe84:c0fc:ffff:ffff:ffff:ffff:ffff:ffff
254fe84:c0fd::/32fe84:c0fd:ffff:ffff:ffff:ffff:ffff:ffff
255fe84:c0fe::/32fe84:c0fe:ffff:ffff:ffff:ffff:ffff:ffff
256fe84:c0ff::/32fe84:c0ff: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.