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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
fe89:c000::/20
First address
fe89:c000::
Last address
fe89: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
fe89:c000:0000:0000:0000:0000:0000:0000
Type
Link-local fe80::/10
Every IPv6 interface has one; not routed
Reverse DNS zone
c.9.8.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)

fe89:c000::/20 makes 65,536 subnets of /36; the first 256 are listed.

Subnets
#SubnetLast address
1fe89:c000::/36fe89:c000:fff:ffff:ffff:ffff:ffff:ffff
2fe89:c000:1000::/36fe89:c000:1fff:ffff:ffff:ffff:ffff:ffff
3fe89:c000:2000::/36fe89:c000:2fff:ffff:ffff:ffff:ffff:ffff
4fe89:c000:3000::/36fe89:c000:3fff:ffff:ffff:ffff:ffff:ffff
5fe89:c000:4000::/36fe89:c000:4fff:ffff:ffff:ffff:ffff:ffff
6fe89:c000:5000::/36fe89:c000:5fff:ffff:ffff:ffff:ffff:ffff
7fe89:c000:6000::/36fe89:c000:6fff:ffff:ffff:ffff:ffff:ffff
8fe89:c000:7000::/36fe89:c000:7fff:ffff:ffff:ffff:ffff:ffff
9fe89:c000:8000::/36fe89:c000:8fff:ffff:ffff:ffff:ffff:ffff
10fe89:c000:9000::/36fe89:c000:9fff:ffff:ffff:ffff:ffff:ffff
11fe89:c000:a000::/36fe89:c000:afff:ffff:ffff:ffff:ffff:ffff
12fe89:c000:b000::/36fe89:c000:bfff:ffff:ffff:ffff:ffff:ffff
13fe89:c000:c000::/36fe89:c000:cfff:ffff:ffff:ffff:ffff:ffff
14fe89:c000:d000::/36fe89:c000:dfff:ffff:ffff:ffff:ffff:ffff
15fe89:c000:e000::/36fe89:c000:efff:ffff:ffff:ffff:ffff:ffff
16fe89:c000:f000::/36fe89:c000:ffff:ffff:ffff:ffff:ffff:ffff
17fe89:c001::/36fe89:c001:fff:ffff:ffff:ffff:ffff:ffff
18fe89:c001:1000::/36fe89:c001:1fff:ffff:ffff:ffff:ffff:ffff
19fe89:c001:2000::/36fe89:c001:2fff:ffff:ffff:ffff:ffff:ffff
20fe89:c001:3000::/36fe89:c001:3fff:ffff:ffff:ffff:ffff:ffff
21fe89:c001:4000::/36fe89:c001:4fff:ffff:ffff:ffff:ffff:ffff
22fe89:c001:5000::/36fe89:c001:5fff:ffff:ffff:ffff:ffff:ffff
23fe89:c001:6000::/36fe89:c001:6fff:ffff:ffff:ffff:ffff:ffff
24fe89:c001:7000::/36fe89:c001:7fff:ffff:ffff:ffff:ffff:ffff
25fe89:c001:8000::/36fe89:c001:8fff:ffff:ffff:ffff:ffff:ffff
26fe89:c001:9000::/36fe89:c001:9fff:ffff:ffff:ffff:ffff:ffff
27fe89:c001:a000::/36fe89:c001:afff:ffff:ffff:ffff:ffff:ffff
28fe89:c001:b000::/36fe89:c001:bfff:ffff:ffff:ffff:ffff:ffff
29fe89:c001:c000::/36fe89:c001:cfff:ffff:ffff:ffff:ffff:ffff
30fe89:c001:d000::/36fe89:c001:dfff:ffff:ffff:ffff:ffff:ffff
31fe89:c001:e000::/36fe89:c001:efff:ffff:ffff:ffff:ffff:ffff
32fe89:c001:f000::/36fe89:c001:ffff:ffff:ffff:ffff:ffff:ffff
33fe89:c002::/36fe89:c002:fff:ffff:ffff:ffff:ffff:ffff
34fe89:c002:1000::/36fe89:c002:1fff:ffff:ffff:ffff:ffff:ffff
35fe89:c002:2000::/36fe89:c002:2fff:ffff:ffff:ffff:ffff:ffff
36fe89:c002:3000::/36fe89:c002:3fff:ffff:ffff:ffff:ffff:ffff
37fe89:c002:4000::/36fe89:c002:4fff:ffff:ffff:ffff:ffff:ffff
38fe89:c002:5000::/36fe89:c002:5fff:ffff:ffff:ffff:ffff:ffff
39fe89:c002:6000::/36fe89:c002:6fff:ffff:ffff:ffff:ffff:ffff
40fe89:c002:7000::/36fe89:c002:7fff:ffff:ffff:ffff:ffff:ffff
41fe89:c002:8000::/36fe89:c002:8fff:ffff:ffff:ffff:ffff:ffff
42fe89:c002:9000::/36fe89:c002:9fff:ffff:ffff:ffff:ffff:ffff
43fe89:c002:a000::/36fe89:c002:afff:ffff:ffff:ffff:ffff:ffff
44fe89:c002:b000::/36fe89:c002:bfff:ffff:ffff:ffff:ffff:ffff
45fe89:c002:c000::/36fe89:c002:cfff:ffff:ffff:ffff:ffff:ffff
46fe89:c002:d000::/36fe89:c002:dfff:ffff:ffff:ffff:ffff:ffff
47fe89:c002:e000::/36fe89:c002:efff:ffff:ffff:ffff:ffff:ffff
48fe89:c002:f000::/36fe89:c002:ffff:ffff:ffff:ffff:ffff:ffff
49fe89:c003::/36fe89:c003:fff:ffff:ffff:ffff:ffff:ffff
50fe89:c003:1000::/36fe89:c003:1fff:ffff:ffff:ffff:ffff:ffff
51fe89:c003:2000::/36fe89:c003:2fff:ffff:ffff:ffff:ffff:ffff
52fe89:c003:3000::/36fe89:c003:3fff:ffff:ffff:ffff:ffff:ffff
53fe89:c003:4000::/36fe89:c003:4fff:ffff:ffff:ffff:ffff:ffff
54fe89:c003:5000::/36fe89:c003:5fff:ffff:ffff:ffff:ffff:ffff
55fe89:c003:6000::/36fe89:c003:6fff:ffff:ffff:ffff:ffff:ffff
56fe89:c003:7000::/36fe89:c003:7fff:ffff:ffff:ffff:ffff:ffff
57fe89:c003:8000::/36fe89:c003:8fff:ffff:ffff:ffff:ffff:ffff
58fe89:c003:9000::/36fe89:c003:9fff:ffff:ffff:ffff:ffff:ffff
59fe89:c003:a000::/36fe89:c003:afff:ffff:ffff:ffff:ffff:ffff
60fe89:c003:b000::/36fe89:c003:bfff:ffff:ffff:ffff:ffff:ffff
61fe89:c003:c000::/36fe89:c003:cfff:ffff:ffff:ffff:ffff:ffff
62fe89:c003:d000::/36fe89:c003:dfff:ffff:ffff:ffff:ffff:ffff
63fe89:c003:e000::/36fe89:c003:efff:ffff:ffff:ffff:ffff:ffff
64fe89:c003:f000::/36fe89:c003:ffff:ffff:ffff:ffff:ffff:ffff
65fe89:c004::/36fe89:c004:fff:ffff:ffff:ffff:ffff:ffff
66fe89:c004:1000::/36fe89:c004:1fff:ffff:ffff:ffff:ffff:ffff
67fe89:c004:2000::/36fe89:c004:2fff:ffff:ffff:ffff:ffff:ffff
68fe89:c004:3000::/36fe89:c004:3fff:ffff:ffff:ffff:ffff:ffff
69fe89:c004:4000::/36fe89:c004:4fff:ffff:ffff:ffff:ffff:ffff
70fe89:c004:5000::/36fe89:c004:5fff:ffff:ffff:ffff:ffff:ffff
71fe89:c004:6000::/36fe89:c004:6fff:ffff:ffff:ffff:ffff:ffff
72fe89:c004:7000::/36fe89:c004:7fff:ffff:ffff:ffff:ffff:ffff
73fe89:c004:8000::/36fe89:c004:8fff:ffff:ffff:ffff:ffff:ffff
74fe89:c004:9000::/36fe89:c004:9fff:ffff:ffff:ffff:ffff:ffff
75fe89:c004:a000::/36fe89:c004:afff:ffff:ffff:ffff:ffff:ffff
76fe89:c004:b000::/36fe89:c004:bfff:ffff:ffff:ffff:ffff:ffff
77fe89:c004:c000::/36fe89:c004:cfff:ffff:ffff:ffff:ffff:ffff
78fe89:c004:d000::/36fe89:c004:dfff:ffff:ffff:ffff:ffff:ffff
79fe89:c004:e000::/36fe89:c004:efff:ffff:ffff:ffff:ffff:ffff
80fe89:c004:f000::/36fe89:c004:ffff:ffff:ffff:ffff:ffff:ffff
81fe89:c005::/36fe89:c005:fff:ffff:ffff:ffff:ffff:ffff
82fe89:c005:1000::/36fe89:c005:1fff:ffff:ffff:ffff:ffff:ffff
83fe89:c005:2000::/36fe89:c005:2fff:ffff:ffff:ffff:ffff:ffff
84fe89:c005:3000::/36fe89:c005:3fff:ffff:ffff:ffff:ffff:ffff
85fe89:c005:4000::/36fe89:c005:4fff:ffff:ffff:ffff:ffff:ffff
86fe89:c005:5000::/36fe89:c005:5fff:ffff:ffff:ffff:ffff:ffff
87fe89:c005:6000::/36fe89:c005:6fff:ffff:ffff:ffff:ffff:ffff
88fe89:c005:7000::/36fe89:c005:7fff:ffff:ffff:ffff:ffff:ffff
89fe89:c005:8000::/36fe89:c005:8fff:ffff:ffff:ffff:ffff:ffff
90fe89:c005:9000::/36fe89:c005:9fff:ffff:ffff:ffff:ffff:ffff
91fe89:c005:a000::/36fe89:c005:afff:ffff:ffff:ffff:ffff:ffff
92fe89:c005:b000::/36fe89:c005:bfff:ffff:ffff:ffff:ffff:ffff
93fe89:c005:c000::/36fe89:c005:cfff:ffff:ffff:ffff:ffff:ffff
94fe89:c005:d000::/36fe89:c005:dfff:ffff:ffff:ffff:ffff:ffff
95fe89:c005:e000::/36fe89:c005:efff:ffff:ffff:ffff:ffff:ffff
96fe89:c005:f000::/36fe89:c005:ffff:ffff:ffff:ffff:ffff:ffff
97fe89:c006::/36fe89:c006:fff:ffff:ffff:ffff:ffff:ffff
98fe89:c006:1000::/36fe89:c006:1fff:ffff:ffff:ffff:ffff:ffff
99fe89:c006:2000::/36fe89:c006:2fff:ffff:ffff:ffff:ffff:ffff
100fe89:c006:3000::/36fe89:c006:3fff:ffff:ffff:ffff:ffff:ffff
101fe89:c006:4000::/36fe89:c006:4fff:ffff:ffff:ffff:ffff:ffff
102fe89:c006:5000::/36fe89:c006:5fff:ffff:ffff:ffff:ffff:ffff
103fe89:c006:6000::/36fe89:c006:6fff:ffff:ffff:ffff:ffff:ffff
104fe89:c006:7000::/36fe89:c006:7fff:ffff:ffff:ffff:ffff:ffff
105fe89:c006:8000::/36fe89:c006:8fff:ffff:ffff:ffff:ffff:ffff
106fe89:c006:9000::/36fe89:c006:9fff:ffff:ffff:ffff:ffff:ffff
107fe89:c006:a000::/36fe89:c006:afff:ffff:ffff:ffff:ffff:ffff
108fe89:c006:b000::/36fe89:c006:bfff:ffff:ffff:ffff:ffff:ffff
109fe89:c006:c000::/36fe89:c006:cfff:ffff:ffff:ffff:ffff:ffff
110fe89:c006:d000::/36fe89:c006:dfff:ffff:ffff:ffff:ffff:ffff
111fe89:c006:e000::/36fe89:c006:efff:ffff:ffff:ffff:ffff:ffff
112fe89:c006:f000::/36fe89:c006:ffff:ffff:ffff:ffff:ffff:ffff
113fe89:c007::/36fe89:c007:fff:ffff:ffff:ffff:ffff:ffff
114fe89:c007:1000::/36fe89:c007:1fff:ffff:ffff:ffff:ffff:ffff
115fe89:c007:2000::/36fe89:c007:2fff:ffff:ffff:ffff:ffff:ffff
116fe89:c007:3000::/36fe89:c007:3fff:ffff:ffff:ffff:ffff:ffff
117fe89:c007:4000::/36fe89:c007:4fff:ffff:ffff:ffff:ffff:ffff
118fe89:c007:5000::/36fe89:c007:5fff:ffff:ffff:ffff:ffff:ffff
119fe89:c007:6000::/36fe89:c007:6fff:ffff:ffff:ffff:ffff:ffff
120fe89:c007:7000::/36fe89:c007:7fff:ffff:ffff:ffff:ffff:ffff
121fe89:c007:8000::/36fe89:c007:8fff:ffff:ffff:ffff:ffff:ffff
122fe89:c007:9000::/36fe89:c007:9fff:ffff:ffff:ffff:ffff:ffff
123fe89:c007:a000::/36fe89:c007:afff:ffff:ffff:ffff:ffff:ffff
124fe89:c007:b000::/36fe89:c007:bfff:ffff:ffff:ffff:ffff:ffff
125fe89:c007:c000::/36fe89:c007:cfff:ffff:ffff:ffff:ffff:ffff
126fe89:c007:d000::/36fe89:c007:dfff:ffff:ffff:ffff:ffff:ffff
127fe89:c007:e000::/36fe89:c007:efff:ffff:ffff:ffff:ffff:ffff
128fe89:c007:f000::/36fe89:c007:ffff:ffff:ffff:ffff:ffff:ffff
129fe89:c008::/36fe89:c008:fff:ffff:ffff:ffff:ffff:ffff
130fe89:c008:1000::/36fe89:c008:1fff:ffff:ffff:ffff:ffff:ffff
131fe89:c008:2000::/36fe89:c008:2fff:ffff:ffff:ffff:ffff:ffff
132fe89:c008:3000::/36fe89:c008:3fff:ffff:ffff:ffff:ffff:ffff
133fe89:c008:4000::/36fe89:c008:4fff:ffff:ffff:ffff:ffff:ffff
134fe89:c008:5000::/36fe89:c008:5fff:ffff:ffff:ffff:ffff:ffff
135fe89:c008:6000::/36fe89:c008:6fff:ffff:ffff:ffff:ffff:ffff
136fe89:c008:7000::/36fe89:c008:7fff:ffff:ffff:ffff:ffff:ffff
137fe89:c008:8000::/36fe89:c008:8fff:ffff:ffff:ffff:ffff:ffff
138fe89:c008:9000::/36fe89:c008:9fff:ffff:ffff:ffff:ffff:ffff
139fe89:c008:a000::/36fe89:c008:afff:ffff:ffff:ffff:ffff:ffff
140fe89:c008:b000::/36fe89:c008:bfff:ffff:ffff:ffff:ffff:ffff
141fe89:c008:c000::/36fe89:c008:cfff:ffff:ffff:ffff:ffff:ffff
142fe89:c008:d000::/36fe89:c008:dfff:ffff:ffff:ffff:ffff:ffff
143fe89:c008:e000::/36fe89:c008:efff:ffff:ffff:ffff:ffff:ffff
144fe89:c008:f000::/36fe89:c008:ffff:ffff:ffff:ffff:ffff:ffff
145fe89:c009::/36fe89:c009:fff:ffff:ffff:ffff:ffff:ffff
146fe89:c009:1000::/36fe89:c009:1fff:ffff:ffff:ffff:ffff:ffff
147fe89:c009:2000::/36fe89:c009:2fff:ffff:ffff:ffff:ffff:ffff
148fe89:c009:3000::/36fe89:c009:3fff:ffff:ffff:ffff:ffff:ffff
149fe89:c009:4000::/36fe89:c009:4fff:ffff:ffff:ffff:ffff:ffff
150fe89:c009:5000::/36fe89:c009:5fff:ffff:ffff:ffff:ffff:ffff
151fe89:c009:6000::/36fe89:c009:6fff:ffff:ffff:ffff:ffff:ffff
152fe89:c009:7000::/36fe89:c009:7fff:ffff:ffff:ffff:ffff:ffff
153fe89:c009:8000::/36fe89:c009:8fff:ffff:ffff:ffff:ffff:ffff
154fe89:c009:9000::/36fe89:c009:9fff:ffff:ffff:ffff:ffff:ffff
155fe89:c009:a000::/36fe89:c009:afff:ffff:ffff:ffff:ffff:ffff
156fe89:c009:b000::/36fe89:c009:bfff:ffff:ffff:ffff:ffff:ffff
157fe89:c009:c000::/36fe89:c009:cfff:ffff:ffff:ffff:ffff:ffff
158fe89:c009:d000::/36fe89:c009:dfff:ffff:ffff:ffff:ffff:ffff
159fe89:c009:e000::/36fe89:c009:efff:ffff:ffff:ffff:ffff:ffff
160fe89:c009:f000::/36fe89:c009:ffff:ffff:ffff:ffff:ffff:ffff
161fe89:c00a::/36fe89:c00a:fff:ffff:ffff:ffff:ffff:ffff
162fe89:c00a:1000::/36fe89:c00a:1fff:ffff:ffff:ffff:ffff:ffff
163fe89:c00a:2000::/36fe89:c00a:2fff:ffff:ffff:ffff:ffff:ffff
164fe89:c00a:3000::/36fe89:c00a:3fff:ffff:ffff:ffff:ffff:ffff
165fe89:c00a:4000::/36fe89:c00a:4fff:ffff:ffff:ffff:ffff:ffff
166fe89:c00a:5000::/36fe89:c00a:5fff:ffff:ffff:ffff:ffff:ffff
167fe89:c00a:6000::/36fe89:c00a:6fff:ffff:ffff:ffff:ffff:ffff
168fe89:c00a:7000::/36fe89:c00a:7fff:ffff:ffff:ffff:ffff:ffff
169fe89:c00a:8000::/36fe89:c00a:8fff:ffff:ffff:ffff:ffff:ffff
170fe89:c00a:9000::/36fe89:c00a:9fff:ffff:ffff:ffff:ffff:ffff
171fe89:c00a:a000::/36fe89:c00a:afff:ffff:ffff:ffff:ffff:ffff
172fe89:c00a:b000::/36fe89:c00a:bfff:ffff:ffff:ffff:ffff:ffff
173fe89:c00a:c000::/36fe89:c00a:cfff:ffff:ffff:ffff:ffff:ffff
174fe89:c00a:d000::/36fe89:c00a:dfff:ffff:ffff:ffff:ffff:ffff
175fe89:c00a:e000::/36fe89:c00a:efff:ffff:ffff:ffff:ffff:ffff
176fe89:c00a:f000::/36fe89:c00a:ffff:ffff:ffff:ffff:ffff:ffff
177fe89:c00b::/36fe89:c00b:fff:ffff:ffff:ffff:ffff:ffff
178fe89:c00b:1000::/36fe89:c00b:1fff:ffff:ffff:ffff:ffff:ffff
179fe89:c00b:2000::/36fe89:c00b:2fff:ffff:ffff:ffff:ffff:ffff
180fe89:c00b:3000::/36fe89:c00b:3fff:ffff:ffff:ffff:ffff:ffff
181fe89:c00b:4000::/36fe89:c00b:4fff:ffff:ffff:ffff:ffff:ffff
182fe89:c00b:5000::/36fe89:c00b:5fff:ffff:ffff:ffff:ffff:ffff
183fe89:c00b:6000::/36fe89:c00b:6fff:ffff:ffff:ffff:ffff:ffff
184fe89:c00b:7000::/36fe89:c00b:7fff:ffff:ffff:ffff:ffff:ffff
185fe89:c00b:8000::/36fe89:c00b:8fff:ffff:ffff:ffff:ffff:ffff
186fe89:c00b:9000::/36fe89:c00b:9fff:ffff:ffff:ffff:ffff:ffff
187fe89:c00b:a000::/36fe89:c00b:afff:ffff:ffff:ffff:ffff:ffff
188fe89:c00b:b000::/36fe89:c00b:bfff:ffff:ffff:ffff:ffff:ffff
189fe89:c00b:c000::/36fe89:c00b:cfff:ffff:ffff:ffff:ffff:ffff
190fe89:c00b:d000::/36fe89:c00b:dfff:ffff:ffff:ffff:ffff:ffff
191fe89:c00b:e000::/36fe89:c00b:efff:ffff:ffff:ffff:ffff:ffff
192fe89:c00b:f000::/36fe89:c00b:ffff:ffff:ffff:ffff:ffff:ffff
193fe89:c00c::/36fe89:c00c:fff:ffff:ffff:ffff:ffff:ffff
194fe89:c00c:1000::/36fe89:c00c:1fff:ffff:ffff:ffff:ffff:ffff
195fe89:c00c:2000::/36fe89:c00c:2fff:ffff:ffff:ffff:ffff:ffff
196fe89:c00c:3000::/36fe89:c00c:3fff:ffff:ffff:ffff:ffff:ffff
197fe89:c00c:4000::/36fe89:c00c:4fff:ffff:ffff:ffff:ffff:ffff
198fe89:c00c:5000::/36fe89:c00c:5fff:ffff:ffff:ffff:ffff:ffff
199fe89:c00c:6000::/36fe89:c00c:6fff:ffff:ffff:ffff:ffff:ffff
200fe89:c00c:7000::/36fe89:c00c:7fff:ffff:ffff:ffff:ffff:ffff
201fe89:c00c:8000::/36fe89:c00c:8fff:ffff:ffff:ffff:ffff:ffff
202fe89:c00c:9000::/36fe89:c00c:9fff:ffff:ffff:ffff:ffff:ffff
203fe89:c00c:a000::/36fe89:c00c:afff:ffff:ffff:ffff:ffff:ffff
204fe89:c00c:b000::/36fe89:c00c:bfff:ffff:ffff:ffff:ffff:ffff
205fe89:c00c:c000::/36fe89:c00c:cfff:ffff:ffff:ffff:ffff:ffff
206fe89:c00c:d000::/36fe89:c00c:dfff:ffff:ffff:ffff:ffff:ffff
207fe89:c00c:e000::/36fe89:c00c:efff:ffff:ffff:ffff:ffff:ffff
208fe89:c00c:f000::/36fe89:c00c:ffff:ffff:ffff:ffff:ffff:ffff
209fe89:c00d::/36fe89:c00d:fff:ffff:ffff:ffff:ffff:ffff
210fe89:c00d:1000::/36fe89:c00d:1fff:ffff:ffff:ffff:ffff:ffff
211fe89:c00d:2000::/36fe89:c00d:2fff:ffff:ffff:ffff:ffff:ffff
212fe89:c00d:3000::/36fe89:c00d:3fff:ffff:ffff:ffff:ffff:ffff
213fe89:c00d:4000::/36fe89:c00d:4fff:ffff:ffff:ffff:ffff:ffff
214fe89:c00d:5000::/36fe89:c00d:5fff:ffff:ffff:ffff:ffff:ffff
215fe89:c00d:6000::/36fe89:c00d:6fff:ffff:ffff:ffff:ffff:ffff
216fe89:c00d:7000::/36fe89:c00d:7fff:ffff:ffff:ffff:ffff:ffff
217fe89:c00d:8000::/36fe89:c00d:8fff:ffff:ffff:ffff:ffff:ffff
218fe89:c00d:9000::/36fe89:c00d:9fff:ffff:ffff:ffff:ffff:ffff
219fe89:c00d:a000::/36fe89:c00d:afff:ffff:ffff:ffff:ffff:ffff
220fe89:c00d:b000::/36fe89:c00d:bfff:ffff:ffff:ffff:ffff:ffff
221fe89:c00d:c000::/36fe89:c00d:cfff:ffff:ffff:ffff:ffff:ffff
222fe89:c00d:d000::/36fe89:c00d:dfff:ffff:ffff:ffff:ffff:ffff
223fe89:c00d:e000::/36fe89:c00d:efff:ffff:ffff:ffff:ffff:ffff
224fe89:c00d:f000::/36fe89:c00d:ffff:ffff:ffff:ffff:ffff:ffff
225fe89:c00e::/36fe89:c00e:fff:ffff:ffff:ffff:ffff:ffff
226fe89:c00e:1000::/36fe89:c00e:1fff:ffff:ffff:ffff:ffff:ffff
227fe89:c00e:2000::/36fe89:c00e:2fff:ffff:ffff:ffff:ffff:ffff
228fe89:c00e:3000::/36fe89:c00e:3fff:ffff:ffff:ffff:ffff:ffff
229fe89:c00e:4000::/36fe89:c00e:4fff:ffff:ffff:ffff:ffff:ffff
230fe89:c00e:5000::/36fe89:c00e:5fff:ffff:ffff:ffff:ffff:ffff
231fe89:c00e:6000::/36fe89:c00e:6fff:ffff:ffff:ffff:ffff:ffff
232fe89:c00e:7000::/36fe89:c00e:7fff:ffff:ffff:ffff:ffff:ffff
233fe89:c00e:8000::/36fe89:c00e:8fff:ffff:ffff:ffff:ffff:ffff
234fe89:c00e:9000::/36fe89:c00e:9fff:ffff:ffff:ffff:ffff:ffff
235fe89:c00e:a000::/36fe89:c00e:afff:ffff:ffff:ffff:ffff:ffff
236fe89:c00e:b000::/36fe89:c00e:bfff:ffff:ffff:ffff:ffff:ffff
237fe89:c00e:c000::/36fe89:c00e:cfff:ffff:ffff:ffff:ffff:ffff
238fe89:c00e:d000::/36fe89:c00e:dfff:ffff:ffff:ffff:ffff:ffff
239fe89:c00e:e000::/36fe89:c00e:efff:ffff:ffff:ffff:ffff:ffff
240fe89:c00e:f000::/36fe89:c00e:ffff:ffff:ffff:ffff:ffff:ffff
241fe89:c00f::/36fe89:c00f:fff:ffff:ffff:ffff:ffff:ffff
242fe89:c00f:1000::/36fe89:c00f:1fff:ffff:ffff:ffff:ffff:ffff
243fe89:c00f:2000::/36fe89:c00f:2fff:ffff:ffff:ffff:ffff:ffff
244fe89:c00f:3000::/36fe89:c00f:3fff:ffff:ffff:ffff:ffff:ffff
245fe89:c00f:4000::/36fe89:c00f:4fff:ffff:ffff:ffff:ffff:ffff
246fe89:c00f:5000::/36fe89:c00f:5fff:ffff:ffff:ffff:ffff:ffff
247fe89:c00f:6000::/36fe89:c00f:6fff:ffff:ffff:ffff:ffff:ffff
248fe89:c00f:7000::/36fe89:c00f:7fff:ffff:ffff:ffff:ffff:ffff
249fe89:c00f:8000::/36fe89:c00f:8fff:ffff:ffff:ffff:ffff:ffff
250fe89:c00f:9000::/36fe89:c00f:9fff:ffff:ffff:ffff:ffff:ffff
251fe89:c00f:a000::/36fe89:c00f:afff:ffff:ffff:ffff:ffff:ffff
252fe89:c00f:b000::/36fe89:c00f:bfff:ffff:ffff:ffff:ffff:ffff
253fe89:c00f:c000::/36fe89:c00f:cfff:ffff:ffff:ffff:ffff:ffff
254fe89:c00f:d000::/36fe89:c00f:dfff:ffff:ffff:ffff:ffff:ffff
255fe89:c00f:e000::/36fe89:c00f:efff:ffff:ffff:ffff:ffff:ffff
256fe89:c00f:f000::/36fe89: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.