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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
fe85:c000::/20
First address
fe85:c000::
Last address
fe85: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
fe85:c000:0000:0000:0000:0000:0000:0000
Type
Link-local fe80::/10
Every IPv6 interface has one; not routed
Reverse DNS zone
c.5.8.e.f.ip6.arpa
Split into smaller subnets/36
/21 (2)/22 (4)/23 (8)/24 (16)/28 (256)/32 (4,096)/36 (65,536)

fe85:c000::/20 makes 65,536 subnets of /36; the first 256 are listed.

Subnets
#SubnetLast address
1fe85:c000::/36fe85:c000:fff:ffff:ffff:ffff:ffff:ffff
2fe85:c000:1000::/36fe85:c000:1fff:ffff:ffff:ffff:ffff:ffff
3fe85:c000:2000::/36fe85:c000:2fff:ffff:ffff:ffff:ffff:ffff
4fe85:c000:3000::/36fe85:c000:3fff:ffff:ffff:ffff:ffff:ffff
5fe85:c000:4000::/36fe85:c000:4fff:ffff:ffff:ffff:ffff:ffff
6fe85:c000:5000::/36fe85:c000:5fff:ffff:ffff:ffff:ffff:ffff
7fe85:c000:6000::/36fe85:c000:6fff:ffff:ffff:ffff:ffff:ffff
8fe85:c000:7000::/36fe85:c000:7fff:ffff:ffff:ffff:ffff:ffff
9fe85:c000:8000::/36fe85:c000:8fff:ffff:ffff:ffff:ffff:ffff
10fe85:c000:9000::/36fe85:c000:9fff:ffff:ffff:ffff:ffff:ffff
11fe85:c000:a000::/36fe85:c000:afff:ffff:ffff:ffff:ffff:ffff
12fe85:c000:b000::/36fe85:c000:bfff:ffff:ffff:ffff:ffff:ffff
13fe85:c000:c000::/36fe85:c000:cfff:ffff:ffff:ffff:ffff:ffff
14fe85:c000:d000::/36fe85:c000:dfff:ffff:ffff:ffff:ffff:ffff
15fe85:c000:e000::/36fe85:c000:efff:ffff:ffff:ffff:ffff:ffff
16fe85:c000:f000::/36fe85:c000:ffff:ffff:ffff:ffff:ffff:ffff
17fe85:c001::/36fe85:c001:fff:ffff:ffff:ffff:ffff:ffff
18fe85:c001:1000::/36fe85:c001:1fff:ffff:ffff:ffff:ffff:ffff
19fe85:c001:2000::/36fe85:c001:2fff:ffff:ffff:ffff:ffff:ffff
20fe85:c001:3000::/36fe85:c001:3fff:ffff:ffff:ffff:ffff:ffff
21fe85:c001:4000::/36fe85:c001:4fff:ffff:ffff:ffff:ffff:ffff
22fe85:c001:5000::/36fe85:c001:5fff:ffff:ffff:ffff:ffff:ffff
23fe85:c001:6000::/36fe85:c001:6fff:ffff:ffff:ffff:ffff:ffff
24fe85:c001:7000::/36fe85:c001:7fff:ffff:ffff:ffff:ffff:ffff
25fe85:c001:8000::/36fe85:c001:8fff:ffff:ffff:ffff:ffff:ffff
26fe85:c001:9000::/36fe85:c001:9fff:ffff:ffff:ffff:ffff:ffff
27fe85:c001:a000::/36fe85:c001:afff:ffff:ffff:ffff:ffff:ffff
28fe85:c001:b000::/36fe85:c001:bfff:ffff:ffff:ffff:ffff:ffff
29fe85:c001:c000::/36fe85:c001:cfff:ffff:ffff:ffff:ffff:ffff
30fe85:c001:d000::/36fe85:c001:dfff:ffff:ffff:ffff:ffff:ffff
31fe85:c001:e000::/36fe85:c001:efff:ffff:ffff:ffff:ffff:ffff
32fe85:c001:f000::/36fe85:c001:ffff:ffff:ffff:ffff:ffff:ffff
33fe85:c002::/36fe85:c002:fff:ffff:ffff:ffff:ffff:ffff
34fe85:c002:1000::/36fe85:c002:1fff:ffff:ffff:ffff:ffff:ffff
35fe85:c002:2000::/36fe85:c002:2fff:ffff:ffff:ffff:ffff:ffff
36fe85:c002:3000::/36fe85:c002:3fff:ffff:ffff:ffff:ffff:ffff
37fe85:c002:4000::/36fe85:c002:4fff:ffff:ffff:ffff:ffff:ffff
38fe85:c002:5000::/36fe85:c002:5fff:ffff:ffff:ffff:ffff:ffff
39fe85:c002:6000::/36fe85:c002:6fff:ffff:ffff:ffff:ffff:ffff
40fe85:c002:7000::/36fe85:c002:7fff:ffff:ffff:ffff:ffff:ffff
41fe85:c002:8000::/36fe85:c002:8fff:ffff:ffff:ffff:ffff:ffff
42fe85:c002:9000::/36fe85:c002:9fff:ffff:ffff:ffff:ffff:ffff
43fe85:c002:a000::/36fe85:c002:afff:ffff:ffff:ffff:ffff:ffff
44fe85:c002:b000::/36fe85:c002:bfff:ffff:ffff:ffff:ffff:ffff
45fe85:c002:c000::/36fe85:c002:cfff:ffff:ffff:ffff:ffff:ffff
46fe85:c002:d000::/36fe85:c002:dfff:ffff:ffff:ffff:ffff:ffff
47fe85:c002:e000::/36fe85:c002:efff:ffff:ffff:ffff:ffff:ffff
48fe85:c002:f000::/36fe85:c002:ffff:ffff:ffff:ffff:ffff:ffff
49fe85:c003::/36fe85:c003:fff:ffff:ffff:ffff:ffff:ffff
50fe85:c003:1000::/36fe85:c003:1fff:ffff:ffff:ffff:ffff:ffff
51fe85:c003:2000::/36fe85:c003:2fff:ffff:ffff:ffff:ffff:ffff
52fe85:c003:3000::/36fe85:c003:3fff:ffff:ffff:ffff:ffff:ffff
53fe85:c003:4000::/36fe85:c003:4fff:ffff:ffff:ffff:ffff:ffff
54fe85:c003:5000::/36fe85:c003:5fff:ffff:ffff:ffff:ffff:ffff
55fe85:c003:6000::/36fe85:c003:6fff:ffff:ffff:ffff:ffff:ffff
56fe85:c003:7000::/36fe85:c003:7fff:ffff:ffff:ffff:ffff:ffff
57fe85:c003:8000::/36fe85:c003:8fff:ffff:ffff:ffff:ffff:ffff
58fe85:c003:9000::/36fe85:c003:9fff:ffff:ffff:ffff:ffff:ffff
59fe85:c003:a000::/36fe85:c003:afff:ffff:ffff:ffff:ffff:ffff
60fe85:c003:b000::/36fe85:c003:bfff:ffff:ffff:ffff:ffff:ffff
61fe85:c003:c000::/36fe85:c003:cfff:ffff:ffff:ffff:ffff:ffff
62fe85:c003:d000::/36fe85:c003:dfff:ffff:ffff:ffff:ffff:ffff
63fe85:c003:e000::/36fe85:c003:efff:ffff:ffff:ffff:ffff:ffff
64fe85:c003:f000::/36fe85:c003:ffff:ffff:ffff:ffff:ffff:ffff
65fe85:c004::/36fe85:c004:fff:ffff:ffff:ffff:ffff:ffff
66fe85:c004:1000::/36fe85:c004:1fff:ffff:ffff:ffff:ffff:ffff
67fe85:c004:2000::/36fe85:c004:2fff:ffff:ffff:ffff:ffff:ffff
68fe85:c004:3000::/36fe85:c004:3fff:ffff:ffff:ffff:ffff:ffff
69fe85:c004:4000::/36fe85:c004:4fff:ffff:ffff:ffff:ffff:ffff
70fe85:c004:5000::/36fe85:c004:5fff:ffff:ffff:ffff:ffff:ffff
71fe85:c004:6000::/36fe85:c004:6fff:ffff:ffff:ffff:ffff:ffff
72fe85:c004:7000::/36fe85:c004:7fff:ffff:ffff:ffff:ffff:ffff
73fe85:c004:8000::/36fe85:c004:8fff:ffff:ffff:ffff:ffff:ffff
74fe85:c004:9000::/36fe85:c004:9fff:ffff:ffff:ffff:ffff:ffff
75fe85:c004:a000::/36fe85:c004:afff:ffff:ffff:ffff:ffff:ffff
76fe85:c004:b000::/36fe85:c004:bfff:ffff:ffff:ffff:ffff:ffff
77fe85:c004:c000::/36fe85:c004:cfff:ffff:ffff:ffff:ffff:ffff
78fe85:c004:d000::/36fe85:c004:dfff:ffff:ffff:ffff:ffff:ffff
79fe85:c004:e000::/36fe85:c004:efff:ffff:ffff:ffff:ffff:ffff
80fe85:c004:f000::/36fe85:c004:ffff:ffff:ffff:ffff:ffff:ffff
81fe85:c005::/36fe85:c005:fff:ffff:ffff:ffff:ffff:ffff
82fe85:c005:1000::/36fe85:c005:1fff:ffff:ffff:ffff:ffff:ffff
83fe85:c005:2000::/36fe85:c005:2fff:ffff:ffff:ffff:ffff:ffff
84fe85:c005:3000::/36fe85:c005:3fff:ffff:ffff:ffff:ffff:ffff
85fe85:c005:4000::/36fe85:c005:4fff:ffff:ffff:ffff:ffff:ffff
86fe85:c005:5000::/36fe85:c005:5fff:ffff:ffff:ffff:ffff:ffff
87fe85:c005:6000::/36fe85:c005:6fff:ffff:ffff:ffff:ffff:ffff
88fe85:c005:7000::/36fe85:c005:7fff:ffff:ffff:ffff:ffff:ffff
89fe85:c005:8000::/36fe85:c005:8fff:ffff:ffff:ffff:ffff:ffff
90fe85:c005:9000::/36fe85:c005:9fff:ffff:ffff:ffff:ffff:ffff
91fe85:c005:a000::/36fe85:c005:afff:ffff:ffff:ffff:ffff:ffff
92fe85:c005:b000::/36fe85:c005:bfff:ffff:ffff:ffff:ffff:ffff
93fe85:c005:c000::/36fe85:c005:cfff:ffff:ffff:ffff:ffff:ffff
94fe85:c005:d000::/36fe85:c005:dfff:ffff:ffff:ffff:ffff:ffff
95fe85:c005:e000::/36fe85:c005:efff:ffff:ffff:ffff:ffff:ffff
96fe85:c005:f000::/36fe85:c005:ffff:ffff:ffff:ffff:ffff:ffff
97fe85:c006::/36fe85:c006:fff:ffff:ffff:ffff:ffff:ffff
98fe85:c006:1000::/36fe85:c006:1fff:ffff:ffff:ffff:ffff:ffff
99fe85:c006:2000::/36fe85:c006:2fff:ffff:ffff:ffff:ffff:ffff
100fe85:c006:3000::/36fe85:c006:3fff:ffff:ffff:ffff:ffff:ffff
101fe85:c006:4000::/36fe85:c006:4fff:ffff:ffff:ffff:ffff:ffff
102fe85:c006:5000::/36fe85:c006:5fff:ffff:ffff:ffff:ffff:ffff
103fe85:c006:6000::/36fe85:c006:6fff:ffff:ffff:ffff:ffff:ffff
104fe85:c006:7000::/36fe85:c006:7fff:ffff:ffff:ffff:ffff:ffff
105fe85:c006:8000::/36fe85:c006:8fff:ffff:ffff:ffff:ffff:ffff
106fe85:c006:9000::/36fe85:c006:9fff:ffff:ffff:ffff:ffff:ffff
107fe85:c006:a000::/36fe85:c006:afff:ffff:ffff:ffff:ffff:ffff
108fe85:c006:b000::/36fe85:c006:bfff:ffff:ffff:ffff:ffff:ffff
109fe85:c006:c000::/36fe85:c006:cfff:ffff:ffff:ffff:ffff:ffff
110fe85:c006:d000::/36fe85:c006:dfff:ffff:ffff:ffff:ffff:ffff
111fe85:c006:e000::/36fe85:c006:efff:ffff:ffff:ffff:ffff:ffff
112fe85:c006:f000::/36fe85:c006:ffff:ffff:ffff:ffff:ffff:ffff
113fe85:c007::/36fe85:c007:fff:ffff:ffff:ffff:ffff:ffff
114fe85:c007:1000::/36fe85:c007:1fff:ffff:ffff:ffff:ffff:ffff
115fe85:c007:2000::/36fe85:c007:2fff:ffff:ffff:ffff:ffff:ffff
116fe85:c007:3000::/36fe85:c007:3fff:ffff:ffff:ffff:ffff:ffff
117fe85:c007:4000::/36fe85:c007:4fff:ffff:ffff:ffff:ffff:ffff
118fe85:c007:5000::/36fe85:c007:5fff:ffff:ffff:ffff:ffff:ffff
119fe85:c007:6000::/36fe85:c007:6fff:ffff:ffff:ffff:ffff:ffff
120fe85:c007:7000::/36fe85:c007:7fff:ffff:ffff:ffff:ffff:ffff
121fe85:c007:8000::/36fe85:c007:8fff:ffff:ffff:ffff:ffff:ffff
122fe85:c007:9000::/36fe85:c007:9fff:ffff:ffff:ffff:ffff:ffff
123fe85:c007:a000::/36fe85:c007:afff:ffff:ffff:ffff:ffff:ffff
124fe85:c007:b000::/36fe85:c007:bfff:ffff:ffff:ffff:ffff:ffff
125fe85:c007:c000::/36fe85:c007:cfff:ffff:ffff:ffff:ffff:ffff
126fe85:c007:d000::/36fe85:c007:dfff:ffff:ffff:ffff:ffff:ffff
127fe85:c007:e000::/36fe85:c007:efff:ffff:ffff:ffff:ffff:ffff
128fe85:c007:f000::/36fe85:c007:ffff:ffff:ffff:ffff:ffff:ffff
129fe85:c008::/36fe85:c008:fff:ffff:ffff:ffff:ffff:ffff
130fe85:c008:1000::/36fe85:c008:1fff:ffff:ffff:ffff:ffff:ffff
131fe85:c008:2000::/36fe85:c008:2fff:ffff:ffff:ffff:ffff:ffff
132fe85:c008:3000::/36fe85:c008:3fff:ffff:ffff:ffff:ffff:ffff
133fe85:c008:4000::/36fe85:c008:4fff:ffff:ffff:ffff:ffff:ffff
134fe85:c008:5000::/36fe85:c008:5fff:ffff:ffff:ffff:ffff:ffff
135fe85:c008:6000::/36fe85:c008:6fff:ffff:ffff:ffff:ffff:ffff
136fe85:c008:7000::/36fe85:c008:7fff:ffff:ffff:ffff:ffff:ffff
137fe85:c008:8000::/36fe85:c008:8fff:ffff:ffff:ffff:ffff:ffff
138fe85:c008:9000::/36fe85:c008:9fff:ffff:ffff:ffff:ffff:ffff
139fe85:c008:a000::/36fe85:c008:afff:ffff:ffff:ffff:ffff:ffff
140fe85:c008:b000::/36fe85:c008:bfff:ffff:ffff:ffff:ffff:ffff
141fe85:c008:c000::/36fe85:c008:cfff:ffff:ffff:ffff:ffff:ffff
142fe85:c008:d000::/36fe85:c008:dfff:ffff:ffff:ffff:ffff:ffff
143fe85:c008:e000::/36fe85:c008:efff:ffff:ffff:ffff:ffff:ffff
144fe85:c008:f000::/36fe85:c008:ffff:ffff:ffff:ffff:ffff:ffff
145fe85:c009::/36fe85:c009:fff:ffff:ffff:ffff:ffff:ffff
146fe85:c009:1000::/36fe85:c009:1fff:ffff:ffff:ffff:ffff:ffff
147fe85:c009:2000::/36fe85:c009:2fff:ffff:ffff:ffff:ffff:ffff
148fe85:c009:3000::/36fe85:c009:3fff:ffff:ffff:ffff:ffff:ffff
149fe85:c009:4000::/36fe85:c009:4fff:ffff:ffff:ffff:ffff:ffff
150fe85:c009:5000::/36fe85:c009:5fff:ffff:ffff:ffff:ffff:ffff
151fe85:c009:6000::/36fe85:c009:6fff:ffff:ffff:ffff:ffff:ffff
152fe85:c009:7000::/36fe85:c009:7fff:ffff:ffff:ffff:ffff:ffff
153fe85:c009:8000::/36fe85:c009:8fff:ffff:ffff:ffff:ffff:ffff
154fe85:c009:9000::/36fe85:c009:9fff:ffff:ffff:ffff:ffff:ffff
155fe85:c009:a000::/36fe85:c009:afff:ffff:ffff:ffff:ffff:ffff
156fe85:c009:b000::/36fe85:c009:bfff:ffff:ffff:ffff:ffff:ffff
157fe85:c009:c000::/36fe85:c009:cfff:ffff:ffff:ffff:ffff:ffff
158fe85:c009:d000::/36fe85:c009:dfff:ffff:ffff:ffff:ffff:ffff
159fe85:c009:e000::/36fe85:c009:efff:ffff:ffff:ffff:ffff:ffff
160fe85:c009:f000::/36fe85:c009:ffff:ffff:ffff:ffff:ffff:ffff
161fe85:c00a::/36fe85:c00a:fff:ffff:ffff:ffff:ffff:ffff
162fe85:c00a:1000::/36fe85:c00a:1fff:ffff:ffff:ffff:ffff:ffff
163fe85:c00a:2000::/36fe85:c00a:2fff:ffff:ffff:ffff:ffff:ffff
164fe85:c00a:3000::/36fe85:c00a:3fff:ffff:ffff:ffff:ffff:ffff
165fe85:c00a:4000::/36fe85:c00a:4fff:ffff:ffff:ffff:ffff:ffff
166fe85:c00a:5000::/36fe85:c00a:5fff:ffff:ffff:ffff:ffff:ffff
167fe85:c00a:6000::/36fe85:c00a:6fff:ffff:ffff:ffff:ffff:ffff
168fe85:c00a:7000::/36fe85:c00a:7fff:ffff:ffff:ffff:ffff:ffff
169fe85:c00a:8000::/36fe85:c00a:8fff:ffff:ffff:ffff:ffff:ffff
170fe85:c00a:9000::/36fe85:c00a:9fff:ffff:ffff:ffff:ffff:ffff
171fe85:c00a:a000::/36fe85:c00a:afff:ffff:ffff:ffff:ffff:ffff
172fe85:c00a:b000::/36fe85:c00a:bfff:ffff:ffff:ffff:ffff:ffff
173fe85:c00a:c000::/36fe85:c00a:cfff:ffff:ffff:ffff:ffff:ffff
174fe85:c00a:d000::/36fe85:c00a:dfff:ffff:ffff:ffff:ffff:ffff
175fe85:c00a:e000::/36fe85:c00a:efff:ffff:ffff:ffff:ffff:ffff
176fe85:c00a:f000::/36fe85:c00a:ffff:ffff:ffff:ffff:ffff:ffff
177fe85:c00b::/36fe85:c00b:fff:ffff:ffff:ffff:ffff:ffff
178fe85:c00b:1000::/36fe85:c00b:1fff:ffff:ffff:ffff:ffff:ffff
179fe85:c00b:2000::/36fe85:c00b:2fff:ffff:ffff:ffff:ffff:ffff
180fe85:c00b:3000::/36fe85:c00b:3fff:ffff:ffff:ffff:ffff:ffff
181fe85:c00b:4000::/36fe85:c00b:4fff:ffff:ffff:ffff:ffff:ffff
182fe85:c00b:5000::/36fe85:c00b:5fff:ffff:ffff:ffff:ffff:ffff
183fe85:c00b:6000::/36fe85:c00b:6fff:ffff:ffff:ffff:ffff:ffff
184fe85:c00b:7000::/36fe85:c00b:7fff:ffff:ffff:ffff:ffff:ffff
185fe85:c00b:8000::/36fe85:c00b:8fff:ffff:ffff:ffff:ffff:ffff
186fe85:c00b:9000::/36fe85:c00b:9fff:ffff:ffff:ffff:ffff:ffff
187fe85:c00b:a000::/36fe85:c00b:afff:ffff:ffff:ffff:ffff:ffff
188fe85:c00b:b000::/36fe85:c00b:bfff:ffff:ffff:ffff:ffff:ffff
189fe85:c00b:c000::/36fe85:c00b:cfff:ffff:ffff:ffff:ffff:ffff
190fe85:c00b:d000::/36fe85:c00b:dfff:ffff:ffff:ffff:ffff:ffff
191fe85:c00b:e000::/36fe85:c00b:efff:ffff:ffff:ffff:ffff:ffff
192fe85:c00b:f000::/36fe85:c00b:ffff:ffff:ffff:ffff:ffff:ffff
193fe85:c00c::/36fe85:c00c:fff:ffff:ffff:ffff:ffff:ffff
194fe85:c00c:1000::/36fe85:c00c:1fff:ffff:ffff:ffff:ffff:ffff
195fe85:c00c:2000::/36fe85:c00c:2fff:ffff:ffff:ffff:ffff:ffff
196fe85:c00c:3000::/36fe85:c00c:3fff:ffff:ffff:ffff:ffff:ffff
197fe85:c00c:4000::/36fe85:c00c:4fff:ffff:ffff:ffff:ffff:ffff
198fe85:c00c:5000::/36fe85:c00c:5fff:ffff:ffff:ffff:ffff:ffff
199fe85:c00c:6000::/36fe85:c00c:6fff:ffff:ffff:ffff:ffff:ffff
200fe85:c00c:7000::/36fe85:c00c:7fff:ffff:ffff:ffff:ffff:ffff
201fe85:c00c:8000::/36fe85:c00c:8fff:ffff:ffff:ffff:ffff:ffff
202fe85:c00c:9000::/36fe85:c00c:9fff:ffff:ffff:ffff:ffff:ffff
203fe85:c00c:a000::/36fe85:c00c:afff:ffff:ffff:ffff:ffff:ffff
204fe85:c00c:b000::/36fe85:c00c:bfff:ffff:ffff:ffff:ffff:ffff
205fe85:c00c:c000::/36fe85:c00c:cfff:ffff:ffff:ffff:ffff:ffff
206fe85:c00c:d000::/36fe85:c00c:dfff:ffff:ffff:ffff:ffff:ffff
207fe85:c00c:e000::/36fe85:c00c:efff:ffff:ffff:ffff:ffff:ffff
208fe85:c00c:f000::/36fe85:c00c:ffff:ffff:ffff:ffff:ffff:ffff
209fe85:c00d::/36fe85:c00d:fff:ffff:ffff:ffff:ffff:ffff
210fe85:c00d:1000::/36fe85:c00d:1fff:ffff:ffff:ffff:ffff:ffff
211fe85:c00d:2000::/36fe85:c00d:2fff:ffff:ffff:ffff:ffff:ffff
212fe85:c00d:3000::/36fe85:c00d:3fff:ffff:ffff:ffff:ffff:ffff
213fe85:c00d:4000::/36fe85:c00d:4fff:ffff:ffff:ffff:ffff:ffff
214fe85:c00d:5000::/36fe85:c00d:5fff:ffff:ffff:ffff:ffff:ffff
215fe85:c00d:6000::/36fe85:c00d:6fff:ffff:ffff:ffff:ffff:ffff
216fe85:c00d:7000::/36fe85:c00d:7fff:ffff:ffff:ffff:ffff:ffff
217fe85:c00d:8000::/36fe85:c00d:8fff:ffff:ffff:ffff:ffff:ffff
218fe85:c00d:9000::/36fe85:c00d:9fff:ffff:ffff:ffff:ffff:ffff
219fe85:c00d:a000::/36fe85:c00d:afff:ffff:ffff:ffff:ffff:ffff
220fe85:c00d:b000::/36fe85:c00d:bfff:ffff:ffff:ffff:ffff:ffff
221fe85:c00d:c000::/36fe85:c00d:cfff:ffff:ffff:ffff:ffff:ffff
222fe85:c00d:d000::/36fe85:c00d:dfff:ffff:ffff:ffff:ffff:ffff
223fe85:c00d:e000::/36fe85:c00d:efff:ffff:ffff:ffff:ffff:ffff
224fe85:c00d:f000::/36fe85:c00d:ffff:ffff:ffff:ffff:ffff:ffff
225fe85:c00e::/36fe85:c00e:fff:ffff:ffff:ffff:ffff:ffff
226fe85:c00e:1000::/36fe85:c00e:1fff:ffff:ffff:ffff:ffff:ffff
227fe85:c00e:2000::/36fe85:c00e:2fff:ffff:ffff:ffff:ffff:ffff
228fe85:c00e:3000::/36fe85:c00e:3fff:ffff:ffff:ffff:ffff:ffff
229fe85:c00e:4000::/36fe85:c00e:4fff:ffff:ffff:ffff:ffff:ffff
230fe85:c00e:5000::/36fe85:c00e:5fff:ffff:ffff:ffff:ffff:ffff
231fe85:c00e:6000::/36fe85:c00e:6fff:ffff:ffff:ffff:ffff:ffff
232fe85:c00e:7000::/36fe85:c00e:7fff:ffff:ffff:ffff:ffff:ffff
233fe85:c00e:8000::/36fe85:c00e:8fff:ffff:ffff:ffff:ffff:ffff
234fe85:c00e:9000::/36fe85:c00e:9fff:ffff:ffff:ffff:ffff:ffff
235fe85:c00e:a000::/36fe85:c00e:afff:ffff:ffff:ffff:ffff:ffff
236fe85:c00e:b000::/36fe85:c00e:bfff:ffff:ffff:ffff:ffff:ffff
237fe85:c00e:c000::/36fe85:c00e:cfff:ffff:ffff:ffff:ffff:ffff
238fe85:c00e:d000::/36fe85:c00e:dfff:ffff:ffff:ffff:ffff:ffff
239fe85:c00e:e000::/36fe85:c00e:efff:ffff:ffff:ffff:ffff:ffff
240fe85:c00e:f000::/36fe85:c00e:ffff:ffff:ffff:ffff:ffff:ffff
241fe85:c00f::/36fe85:c00f:fff:ffff:ffff:ffff:ffff:ffff
242fe85:c00f:1000::/36fe85:c00f:1fff:ffff:ffff:ffff:ffff:ffff
243fe85:c00f:2000::/36fe85:c00f:2fff:ffff:ffff:ffff:ffff:ffff
244fe85:c00f:3000::/36fe85:c00f:3fff:ffff:ffff:ffff:ffff:ffff
245fe85:c00f:4000::/36fe85:c00f:4fff:ffff:ffff:ffff:ffff:ffff
246fe85:c00f:5000::/36fe85:c00f:5fff:ffff:ffff:ffff:ffff:ffff
247fe85:c00f:6000::/36fe85:c00f:6fff:ffff:ffff:ffff:ffff:ffff
248fe85:c00f:7000::/36fe85:c00f:7fff:ffff:ffff:ffff:ffff:ffff
249fe85:c00f:8000::/36fe85:c00f:8fff:ffff:ffff:ffff:ffff:ffff
250fe85:c00f:9000::/36fe85:c00f:9fff:ffff:ffff:ffff:ffff:ffff
251fe85:c00f:a000::/36fe85:c00f:afff:ffff:ffff:ffff:ffff:ffff
252fe85:c00f:b000::/36fe85:c00f:bfff:ffff:ffff:ffff:ffff:ffff
253fe85:c00f:c000::/36fe85:c00f:cfff:ffff:ffff:ffff:ffff:ffff
254fe85:c00f:d000::/36fe85:c00f:dfff:ffff:ffff:ffff:ffff:ffff
255fe85:c00f:e000::/36fe85:c00f:efff:ffff:ffff:ffff:ffff:ffff
256fe85:c00f:f000::/36fe85:c00f: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.