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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/100
Addresses268,435,456
/64 networksPart of one
Network
fe80:c25b:dd:dd:dd06::/100
First address
fe80:c25b:dd:dd:dd06::
Last address
fe80:c25b:dd:dd:dd06:0:fff:ffff
Addresses
268,435,456
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
fe80:c25b:00dd:00dd:dd06:0000:0000:0000
Type
Link-local fe80::/10
Every IPv6 interface has one; not routed
Reverse DNS zone
0.0.0.0.0.6.0.d.d.d.d.0.0.d.d.0.0.b.5.2.c.0.8.e.f.ip6.arpa
Split into smaller subnets/116
/101 (2)/102 (4)/103 (8)/104 (16)/108 (256)/112 (4,096)/116 (65,536)

fe80:c25b:dd:dd:dd06::/100 makes 65,536 subnets of /116; the first 256 are listed.

Subnets
#SubnetLast address
1fe80:c25b:dd:dd:dd06::/116fe80:c25b:dd:dd:dd06::fff
2fe80:c25b:dd:dd:dd06::1000/116fe80:c25b:dd:dd:dd06::1fff
3fe80:c25b:dd:dd:dd06::2000/116fe80:c25b:dd:dd:dd06::2fff
4fe80:c25b:dd:dd:dd06::3000/116fe80:c25b:dd:dd:dd06::3fff
5fe80:c25b:dd:dd:dd06::4000/116fe80:c25b:dd:dd:dd06::4fff
6fe80:c25b:dd:dd:dd06::5000/116fe80:c25b:dd:dd:dd06::5fff
7fe80:c25b:dd:dd:dd06::6000/116fe80:c25b:dd:dd:dd06::6fff
8fe80:c25b:dd:dd:dd06::7000/116fe80:c25b:dd:dd:dd06::7fff
9fe80:c25b:dd:dd:dd06::8000/116fe80:c25b:dd:dd:dd06::8fff
10fe80:c25b:dd:dd:dd06::9000/116fe80:c25b:dd:dd:dd06::9fff
11fe80:c25b:dd:dd:dd06::a000/116fe80:c25b:dd:dd:dd06::afff
12fe80:c25b:dd:dd:dd06::b000/116fe80:c25b:dd:dd:dd06::bfff
13fe80:c25b:dd:dd:dd06::c000/116fe80:c25b:dd:dd:dd06::cfff
14fe80:c25b:dd:dd:dd06::d000/116fe80:c25b:dd:dd:dd06::dfff
15fe80:c25b:dd:dd:dd06::e000/116fe80:c25b:dd:dd:dd06::efff
16fe80:c25b:dd:dd:dd06::f000/116fe80:c25b:dd:dd:dd06::ffff
17fe80:c25b:dd:dd:dd06:0:1:0/116fe80:c25b:dd:dd:dd06:0:1:fff
18fe80:c25b:dd:dd:dd06:0:1:1000/116fe80:c25b:dd:dd:dd06:0:1:1fff
19fe80:c25b:dd:dd:dd06:0:1:2000/116fe80:c25b:dd:dd:dd06:0:1:2fff
20fe80:c25b:dd:dd:dd06:0:1:3000/116fe80:c25b:dd:dd:dd06:0:1:3fff
21fe80:c25b:dd:dd:dd06:0:1:4000/116fe80:c25b:dd:dd:dd06:0:1:4fff
22fe80:c25b:dd:dd:dd06:0:1:5000/116fe80:c25b:dd:dd:dd06:0:1:5fff
23fe80:c25b:dd:dd:dd06:0:1:6000/116fe80:c25b:dd:dd:dd06:0:1:6fff
24fe80:c25b:dd:dd:dd06:0:1:7000/116fe80:c25b:dd:dd:dd06:0:1:7fff
25fe80:c25b:dd:dd:dd06:0:1:8000/116fe80:c25b:dd:dd:dd06:0:1:8fff
26fe80:c25b:dd:dd:dd06:0:1:9000/116fe80:c25b:dd:dd:dd06:0:1:9fff
27fe80:c25b:dd:dd:dd06:0:1:a000/116fe80:c25b:dd:dd:dd06:0:1:afff
28fe80:c25b:dd:dd:dd06:0:1:b000/116fe80:c25b:dd:dd:dd06:0:1:bfff
29fe80:c25b:dd:dd:dd06:0:1:c000/116fe80:c25b:dd:dd:dd06:0:1:cfff
30fe80:c25b:dd:dd:dd06:0:1:d000/116fe80:c25b:dd:dd:dd06:0:1:dfff
31fe80:c25b:dd:dd:dd06:0:1:e000/116fe80:c25b:dd:dd:dd06:0:1:efff
32fe80:c25b:dd:dd:dd06:0:1:f000/116fe80:c25b:dd:dd:dd06:0:1:ffff
33fe80:c25b:dd:dd:dd06:0:2:0/116fe80:c25b:dd:dd:dd06:0:2:fff
34fe80:c25b:dd:dd:dd06:0:2:1000/116fe80:c25b:dd:dd:dd06:0:2:1fff
35fe80:c25b:dd:dd:dd06:0:2:2000/116fe80:c25b:dd:dd:dd06:0:2:2fff
36fe80:c25b:dd:dd:dd06:0:2:3000/116fe80:c25b:dd:dd:dd06:0:2:3fff
37fe80:c25b:dd:dd:dd06:0:2:4000/116fe80:c25b:dd:dd:dd06:0:2:4fff
38fe80:c25b:dd:dd:dd06:0:2:5000/116fe80:c25b:dd:dd:dd06:0:2:5fff
39fe80:c25b:dd:dd:dd06:0:2:6000/116fe80:c25b:dd:dd:dd06:0:2:6fff
40fe80:c25b:dd:dd:dd06:0:2:7000/116fe80:c25b:dd:dd:dd06:0:2:7fff
41fe80:c25b:dd:dd:dd06:0:2:8000/116fe80:c25b:dd:dd:dd06:0:2:8fff
42fe80:c25b:dd:dd:dd06:0:2:9000/116fe80:c25b:dd:dd:dd06:0:2:9fff
43fe80:c25b:dd:dd:dd06:0:2:a000/116fe80:c25b:dd:dd:dd06:0:2:afff
44fe80:c25b:dd:dd:dd06:0:2:b000/116fe80:c25b:dd:dd:dd06:0:2:bfff
45fe80:c25b:dd:dd:dd06:0:2:c000/116fe80:c25b:dd:dd:dd06:0:2:cfff
46fe80:c25b:dd:dd:dd06:0:2:d000/116fe80:c25b:dd:dd:dd06:0:2:dfff
47fe80:c25b:dd:dd:dd06:0:2:e000/116fe80:c25b:dd:dd:dd06:0:2:efff
48fe80:c25b:dd:dd:dd06:0:2:f000/116fe80:c25b:dd:dd:dd06:0:2:ffff
49fe80:c25b:dd:dd:dd06:0:3:0/116fe80:c25b:dd:dd:dd06:0:3:fff
50fe80:c25b:dd:dd:dd06:0:3:1000/116fe80:c25b:dd:dd:dd06:0:3:1fff
51fe80:c25b:dd:dd:dd06:0:3:2000/116fe80:c25b:dd:dd:dd06:0:3:2fff
52fe80:c25b:dd:dd:dd06:0:3:3000/116fe80:c25b:dd:dd:dd06:0:3:3fff
53fe80:c25b:dd:dd:dd06:0:3:4000/116fe80:c25b:dd:dd:dd06:0:3:4fff
54fe80:c25b:dd:dd:dd06:0:3:5000/116fe80:c25b:dd:dd:dd06:0:3:5fff
55fe80:c25b:dd:dd:dd06:0:3:6000/116fe80:c25b:dd:dd:dd06:0:3:6fff
56fe80:c25b:dd:dd:dd06:0:3:7000/116fe80:c25b:dd:dd:dd06:0:3:7fff
57fe80:c25b:dd:dd:dd06:0:3:8000/116fe80:c25b:dd:dd:dd06:0:3:8fff
58fe80:c25b:dd:dd:dd06:0:3:9000/116fe80:c25b:dd:dd:dd06:0:3:9fff
59fe80:c25b:dd:dd:dd06:0:3:a000/116fe80:c25b:dd:dd:dd06:0:3:afff
60fe80:c25b:dd:dd:dd06:0:3:b000/116fe80:c25b:dd:dd:dd06:0:3:bfff
61fe80:c25b:dd:dd:dd06:0:3:c000/116fe80:c25b:dd:dd:dd06:0:3:cfff
62fe80:c25b:dd:dd:dd06:0:3:d000/116fe80:c25b:dd:dd:dd06:0:3:dfff
63fe80:c25b:dd:dd:dd06:0:3:e000/116fe80:c25b:dd:dd:dd06:0:3:efff
64fe80:c25b:dd:dd:dd06:0:3:f000/116fe80:c25b:dd:dd:dd06:0:3:ffff
65fe80:c25b:dd:dd:dd06:0:4:0/116fe80:c25b:dd:dd:dd06:0:4:fff
66fe80:c25b:dd:dd:dd06:0:4:1000/116fe80:c25b:dd:dd:dd06:0:4:1fff
67fe80:c25b:dd:dd:dd06:0:4:2000/116fe80:c25b:dd:dd:dd06:0:4:2fff
68fe80:c25b:dd:dd:dd06:0:4:3000/116fe80:c25b:dd:dd:dd06:0:4:3fff
69fe80:c25b:dd:dd:dd06:0:4:4000/116fe80:c25b:dd:dd:dd06:0:4:4fff
70fe80:c25b:dd:dd:dd06:0:4:5000/116fe80:c25b:dd:dd:dd06:0:4:5fff
71fe80:c25b:dd:dd:dd06:0:4:6000/116fe80:c25b:dd:dd:dd06:0:4:6fff
72fe80:c25b:dd:dd:dd06:0:4:7000/116fe80:c25b:dd:dd:dd06:0:4:7fff
73fe80:c25b:dd:dd:dd06:0:4:8000/116fe80:c25b:dd:dd:dd06:0:4:8fff
74fe80:c25b:dd:dd:dd06:0:4:9000/116fe80:c25b:dd:dd:dd06:0:4:9fff
75fe80:c25b:dd:dd:dd06:0:4:a000/116fe80:c25b:dd:dd:dd06:0:4:afff
76fe80:c25b:dd:dd:dd06:0:4:b000/116fe80:c25b:dd:dd:dd06:0:4:bfff
77fe80:c25b:dd:dd:dd06:0:4:c000/116fe80:c25b:dd:dd:dd06:0:4:cfff
78fe80:c25b:dd:dd:dd06:0:4:d000/116fe80:c25b:dd:dd:dd06:0:4:dfff
79fe80:c25b:dd:dd:dd06:0:4:e000/116fe80:c25b:dd:dd:dd06:0:4:efff
80fe80:c25b:dd:dd:dd06:0:4:f000/116fe80:c25b:dd:dd:dd06:0:4:ffff
81fe80:c25b:dd:dd:dd06:0:5:0/116fe80:c25b:dd:dd:dd06:0:5:fff
82fe80:c25b:dd:dd:dd06:0:5:1000/116fe80:c25b:dd:dd:dd06:0:5:1fff
83fe80:c25b:dd:dd:dd06:0:5:2000/116fe80:c25b:dd:dd:dd06:0:5:2fff
84fe80:c25b:dd:dd:dd06:0:5:3000/116fe80:c25b:dd:dd:dd06:0:5:3fff
85fe80:c25b:dd:dd:dd06:0:5:4000/116fe80:c25b:dd:dd:dd06:0:5:4fff
86fe80:c25b:dd:dd:dd06:0:5:5000/116fe80:c25b:dd:dd:dd06:0:5:5fff
87fe80:c25b:dd:dd:dd06:0:5:6000/116fe80:c25b:dd:dd:dd06:0:5:6fff
88fe80:c25b:dd:dd:dd06:0:5:7000/116fe80:c25b:dd:dd:dd06:0:5:7fff
89fe80:c25b:dd:dd:dd06:0:5:8000/116fe80:c25b:dd:dd:dd06:0:5:8fff
90fe80:c25b:dd:dd:dd06:0:5:9000/116fe80:c25b:dd:dd:dd06:0:5:9fff
91fe80:c25b:dd:dd:dd06:0:5:a000/116fe80:c25b:dd:dd:dd06:0:5:afff
92fe80:c25b:dd:dd:dd06:0:5:b000/116fe80:c25b:dd:dd:dd06:0:5:bfff
93fe80:c25b:dd:dd:dd06:0:5:c000/116fe80:c25b:dd:dd:dd06:0:5:cfff
94fe80:c25b:dd:dd:dd06:0:5:d000/116fe80:c25b:dd:dd:dd06:0:5:dfff
95fe80:c25b:dd:dd:dd06:0:5:e000/116fe80:c25b:dd:dd:dd06:0:5:efff
96fe80:c25b:dd:dd:dd06:0:5:f000/116fe80:c25b:dd:dd:dd06:0:5:ffff
97fe80:c25b:dd:dd:dd06:0:6:0/116fe80:c25b:dd:dd:dd06:0:6:fff
98fe80:c25b:dd:dd:dd06:0:6:1000/116fe80:c25b:dd:dd:dd06:0:6:1fff
99fe80:c25b:dd:dd:dd06:0:6:2000/116fe80:c25b:dd:dd:dd06:0:6:2fff
100fe80:c25b:dd:dd:dd06:0:6:3000/116fe80:c25b:dd:dd:dd06:0:6:3fff
101fe80:c25b:dd:dd:dd06:0:6:4000/116fe80:c25b:dd:dd:dd06:0:6:4fff
102fe80:c25b:dd:dd:dd06:0:6:5000/116fe80:c25b:dd:dd:dd06:0:6:5fff
103fe80:c25b:dd:dd:dd06:0:6:6000/116fe80:c25b:dd:dd:dd06:0:6:6fff
104fe80:c25b:dd:dd:dd06:0:6:7000/116fe80:c25b:dd:dd:dd06:0:6:7fff
105fe80:c25b:dd:dd:dd06:0:6:8000/116fe80:c25b:dd:dd:dd06:0:6:8fff
106fe80:c25b:dd:dd:dd06:0:6:9000/116fe80:c25b:dd:dd:dd06:0:6:9fff
107fe80:c25b:dd:dd:dd06:0:6:a000/116fe80:c25b:dd:dd:dd06:0:6:afff
108fe80:c25b:dd:dd:dd06:0:6:b000/116fe80:c25b:dd:dd:dd06:0:6:bfff
109fe80:c25b:dd:dd:dd06:0:6:c000/116fe80:c25b:dd:dd:dd06:0:6:cfff
110fe80:c25b:dd:dd:dd06:0:6:d000/116fe80:c25b:dd:dd:dd06:0:6:dfff
111fe80:c25b:dd:dd:dd06:0:6:e000/116fe80:c25b:dd:dd:dd06:0:6:efff
112fe80:c25b:dd:dd:dd06:0:6:f000/116fe80:c25b:dd:dd:dd06:0:6:ffff
113fe80:c25b:dd:dd:dd06:0:7:0/116fe80:c25b:dd:dd:dd06:0:7:fff
114fe80:c25b:dd:dd:dd06:0:7:1000/116fe80:c25b:dd:dd:dd06:0:7:1fff
115fe80:c25b:dd:dd:dd06:0:7:2000/116fe80:c25b:dd:dd:dd06:0:7:2fff
116fe80:c25b:dd:dd:dd06:0:7:3000/116fe80:c25b:dd:dd:dd06:0:7:3fff
117fe80:c25b:dd:dd:dd06:0:7:4000/116fe80:c25b:dd:dd:dd06:0:7:4fff
118fe80:c25b:dd:dd:dd06:0:7:5000/116fe80:c25b:dd:dd:dd06:0:7:5fff
119fe80:c25b:dd:dd:dd06:0:7:6000/116fe80:c25b:dd:dd:dd06:0:7:6fff
120fe80:c25b:dd:dd:dd06:0:7:7000/116fe80:c25b:dd:dd:dd06:0:7:7fff
121fe80:c25b:dd:dd:dd06:0:7:8000/116fe80:c25b:dd:dd:dd06:0:7:8fff
122fe80:c25b:dd:dd:dd06:0:7:9000/116fe80:c25b:dd:dd:dd06:0:7:9fff
123fe80:c25b:dd:dd:dd06:0:7:a000/116fe80:c25b:dd:dd:dd06:0:7:afff
124fe80:c25b:dd:dd:dd06:0:7:b000/116fe80:c25b:dd:dd:dd06:0:7:bfff
125fe80:c25b:dd:dd:dd06:0:7:c000/116fe80:c25b:dd:dd:dd06:0:7:cfff
126fe80:c25b:dd:dd:dd06:0:7:d000/116fe80:c25b:dd:dd:dd06:0:7:dfff
127fe80:c25b:dd:dd:dd06:0:7:e000/116fe80:c25b:dd:dd:dd06:0:7:efff
128fe80:c25b:dd:dd:dd06:0:7:f000/116fe80:c25b:dd:dd:dd06:0:7:ffff
129fe80:c25b:dd:dd:dd06:0:8:0/116fe80:c25b:dd:dd:dd06:0:8:fff
130fe80:c25b:dd:dd:dd06:0:8:1000/116fe80:c25b:dd:dd:dd06:0:8:1fff
131fe80:c25b:dd:dd:dd06:0:8:2000/116fe80:c25b:dd:dd:dd06:0:8:2fff
132fe80:c25b:dd:dd:dd06:0:8:3000/116fe80:c25b:dd:dd:dd06:0:8:3fff
133fe80:c25b:dd:dd:dd06:0:8:4000/116fe80:c25b:dd:dd:dd06:0:8:4fff
134fe80:c25b:dd:dd:dd06:0:8:5000/116fe80:c25b:dd:dd:dd06:0:8:5fff
135fe80:c25b:dd:dd:dd06:0:8:6000/116fe80:c25b:dd:dd:dd06:0:8:6fff
136fe80:c25b:dd:dd:dd06:0:8:7000/116fe80:c25b:dd:dd:dd06:0:8:7fff
137fe80:c25b:dd:dd:dd06:0:8:8000/116fe80:c25b:dd:dd:dd06:0:8:8fff
138fe80:c25b:dd:dd:dd06:0:8:9000/116fe80:c25b:dd:dd:dd06:0:8:9fff
139fe80:c25b:dd:dd:dd06:0:8:a000/116fe80:c25b:dd:dd:dd06:0:8:afff
140fe80:c25b:dd:dd:dd06:0:8:b000/116fe80:c25b:dd:dd:dd06:0:8:bfff
141fe80:c25b:dd:dd:dd06:0:8:c000/116fe80:c25b:dd:dd:dd06:0:8:cfff
142fe80:c25b:dd:dd:dd06:0:8:d000/116fe80:c25b:dd:dd:dd06:0:8:dfff
143fe80:c25b:dd:dd:dd06:0:8:e000/116fe80:c25b:dd:dd:dd06:0:8:efff
144fe80:c25b:dd:dd:dd06:0:8:f000/116fe80:c25b:dd:dd:dd06:0:8:ffff
145fe80:c25b:dd:dd:dd06:0:9:0/116fe80:c25b:dd:dd:dd06:0:9:fff
146fe80:c25b:dd:dd:dd06:0:9:1000/116fe80:c25b:dd:dd:dd06:0:9:1fff
147fe80:c25b:dd:dd:dd06:0:9:2000/116fe80:c25b:dd:dd:dd06:0:9:2fff
148fe80:c25b:dd:dd:dd06:0:9:3000/116fe80:c25b:dd:dd:dd06:0:9:3fff
149fe80:c25b:dd:dd:dd06:0:9:4000/116fe80:c25b:dd:dd:dd06:0:9:4fff
150fe80:c25b:dd:dd:dd06:0:9:5000/116fe80:c25b:dd:dd:dd06:0:9:5fff
151fe80:c25b:dd:dd:dd06:0:9:6000/116fe80:c25b:dd:dd:dd06:0:9:6fff
152fe80:c25b:dd:dd:dd06:0:9:7000/116fe80:c25b:dd:dd:dd06:0:9:7fff
153fe80:c25b:dd:dd:dd06:0:9:8000/116fe80:c25b:dd:dd:dd06:0:9:8fff
154fe80:c25b:dd:dd:dd06:0:9:9000/116fe80:c25b:dd:dd:dd06:0:9:9fff
155fe80:c25b:dd:dd:dd06:0:9:a000/116fe80:c25b:dd:dd:dd06:0:9:afff
156fe80:c25b:dd:dd:dd06:0:9:b000/116fe80:c25b:dd:dd:dd06:0:9:bfff
157fe80:c25b:dd:dd:dd06:0:9:c000/116fe80:c25b:dd:dd:dd06:0:9:cfff
158fe80:c25b:dd:dd:dd06:0:9:d000/116fe80:c25b:dd:dd:dd06:0:9:dfff
159fe80:c25b:dd:dd:dd06:0:9:e000/116fe80:c25b:dd:dd:dd06:0:9:efff
160fe80:c25b:dd:dd:dd06:0:9:f000/116fe80:c25b:dd:dd:dd06:0:9:ffff
161fe80:c25b:dd:dd:dd06:0:a:0/116fe80:c25b:dd:dd:dd06:0:a:fff
162fe80:c25b:dd:dd:dd06:0:a:1000/116fe80:c25b:dd:dd:dd06:0:a:1fff
163fe80:c25b:dd:dd:dd06:0:a:2000/116fe80:c25b:dd:dd:dd06:0:a:2fff
164fe80:c25b:dd:dd:dd06:0:a:3000/116fe80:c25b:dd:dd:dd06:0:a:3fff
165fe80:c25b:dd:dd:dd06:0:a:4000/116fe80:c25b:dd:dd:dd06:0:a:4fff
166fe80:c25b:dd:dd:dd06:0:a:5000/116fe80:c25b:dd:dd:dd06:0:a:5fff
167fe80:c25b:dd:dd:dd06:0:a:6000/116fe80:c25b:dd:dd:dd06:0:a:6fff
168fe80:c25b:dd:dd:dd06:0:a:7000/116fe80:c25b:dd:dd:dd06:0:a:7fff
169fe80:c25b:dd:dd:dd06:0:a:8000/116fe80:c25b:dd:dd:dd06:0:a:8fff
170fe80:c25b:dd:dd:dd06:0:a:9000/116fe80:c25b:dd:dd:dd06:0:a:9fff
171fe80:c25b:dd:dd:dd06:0:a:a000/116fe80:c25b:dd:dd:dd06:0:a:afff
172fe80:c25b:dd:dd:dd06:0:a:b000/116fe80:c25b:dd:dd:dd06:0:a:bfff
173fe80:c25b:dd:dd:dd06:0:a:c000/116fe80:c25b:dd:dd:dd06:0:a:cfff
174fe80:c25b:dd:dd:dd06:0:a:d000/116fe80:c25b:dd:dd:dd06:0:a:dfff
175fe80:c25b:dd:dd:dd06:0:a:e000/116fe80:c25b:dd:dd:dd06:0:a:efff
176fe80:c25b:dd:dd:dd06:0:a:f000/116fe80:c25b:dd:dd:dd06:0:a:ffff
177fe80:c25b:dd:dd:dd06:0:b:0/116fe80:c25b:dd:dd:dd06:0:b:fff
178fe80:c25b:dd:dd:dd06:0:b:1000/116fe80:c25b:dd:dd:dd06:0:b:1fff
179fe80:c25b:dd:dd:dd06:0:b:2000/116fe80:c25b:dd:dd:dd06:0:b:2fff
180fe80:c25b:dd:dd:dd06:0:b:3000/116fe80:c25b:dd:dd:dd06:0:b:3fff
181fe80:c25b:dd:dd:dd06:0:b:4000/116fe80:c25b:dd:dd:dd06:0:b:4fff
182fe80:c25b:dd:dd:dd06:0:b:5000/116fe80:c25b:dd:dd:dd06:0:b:5fff
183fe80:c25b:dd:dd:dd06:0:b:6000/116fe80:c25b:dd:dd:dd06:0:b:6fff
184fe80:c25b:dd:dd:dd06:0:b:7000/116fe80:c25b:dd:dd:dd06:0:b:7fff
185fe80:c25b:dd:dd:dd06:0:b:8000/116fe80:c25b:dd:dd:dd06:0:b:8fff
186fe80:c25b:dd:dd:dd06:0:b:9000/116fe80:c25b:dd:dd:dd06:0:b:9fff
187fe80:c25b:dd:dd:dd06:0:b:a000/116fe80:c25b:dd:dd:dd06:0:b:afff
188fe80:c25b:dd:dd:dd06:0:b:b000/116fe80:c25b:dd:dd:dd06:0:b:bfff
189fe80:c25b:dd:dd:dd06:0:b:c000/116fe80:c25b:dd:dd:dd06:0:b:cfff
190fe80:c25b:dd:dd:dd06:0:b:d000/116fe80:c25b:dd:dd:dd06:0:b:dfff
191fe80:c25b:dd:dd:dd06:0:b:e000/116fe80:c25b:dd:dd:dd06:0:b:efff
192fe80:c25b:dd:dd:dd06:0:b:f000/116fe80:c25b:dd:dd:dd06:0:b:ffff
193fe80:c25b:dd:dd:dd06:0:c:0/116fe80:c25b:dd:dd:dd06:0:c:fff
194fe80:c25b:dd:dd:dd06:0:c:1000/116fe80:c25b:dd:dd:dd06:0:c:1fff
195fe80:c25b:dd:dd:dd06:0:c:2000/116fe80:c25b:dd:dd:dd06:0:c:2fff
196fe80:c25b:dd:dd:dd06:0:c:3000/116fe80:c25b:dd:dd:dd06:0:c:3fff
197fe80:c25b:dd:dd:dd06:0:c:4000/116fe80:c25b:dd:dd:dd06:0:c:4fff
198fe80:c25b:dd:dd:dd06:0:c:5000/116fe80:c25b:dd:dd:dd06:0:c:5fff
199fe80:c25b:dd:dd:dd06:0:c:6000/116fe80:c25b:dd:dd:dd06:0:c:6fff
200fe80:c25b:dd:dd:dd06:0:c:7000/116fe80:c25b:dd:dd:dd06:0:c:7fff
201fe80:c25b:dd:dd:dd06:0:c:8000/116fe80:c25b:dd:dd:dd06:0:c:8fff
202fe80:c25b:dd:dd:dd06:0:c:9000/116fe80:c25b:dd:dd:dd06:0:c:9fff
203fe80:c25b:dd:dd:dd06:0:c:a000/116fe80:c25b:dd:dd:dd06:0:c:afff
204fe80:c25b:dd:dd:dd06:0:c:b000/116fe80:c25b:dd:dd:dd06:0:c:bfff
205fe80:c25b:dd:dd:dd06:0:c:c000/116fe80:c25b:dd:dd:dd06:0:c:cfff
206fe80:c25b:dd:dd:dd06:0:c:d000/116fe80:c25b:dd:dd:dd06:0:c:dfff
207fe80:c25b:dd:dd:dd06:0:c:e000/116fe80:c25b:dd:dd:dd06:0:c:efff
208fe80:c25b:dd:dd:dd06:0:c:f000/116fe80:c25b:dd:dd:dd06:0:c:ffff
209fe80:c25b:dd:dd:dd06:0:d:0/116fe80:c25b:dd:dd:dd06:0:d:fff
210fe80:c25b:dd:dd:dd06:0:d:1000/116fe80:c25b:dd:dd:dd06:0:d:1fff
211fe80:c25b:dd:dd:dd06:0:d:2000/116fe80:c25b:dd:dd:dd06:0:d:2fff
212fe80:c25b:dd:dd:dd06:0:d:3000/116fe80:c25b:dd:dd:dd06:0:d:3fff
213fe80:c25b:dd:dd:dd06:0:d:4000/116fe80:c25b:dd:dd:dd06:0:d:4fff
214fe80:c25b:dd:dd:dd06:0:d:5000/116fe80:c25b:dd:dd:dd06:0:d:5fff
215fe80:c25b:dd:dd:dd06:0:d:6000/116fe80:c25b:dd:dd:dd06:0:d:6fff
216fe80:c25b:dd:dd:dd06:0:d:7000/116fe80:c25b:dd:dd:dd06:0:d:7fff
217fe80:c25b:dd:dd:dd06:0:d:8000/116fe80:c25b:dd:dd:dd06:0:d:8fff
218fe80:c25b:dd:dd:dd06:0:d:9000/116fe80:c25b:dd:dd:dd06:0:d:9fff
219fe80:c25b:dd:dd:dd06:0:d:a000/116fe80:c25b:dd:dd:dd06:0:d:afff
220fe80:c25b:dd:dd:dd06:0:d:b000/116fe80:c25b:dd:dd:dd06:0:d:bfff
221fe80:c25b:dd:dd:dd06:0:d:c000/116fe80:c25b:dd:dd:dd06:0:d:cfff
222fe80:c25b:dd:dd:dd06:0:d:d000/116fe80:c25b:dd:dd:dd06:0:d:dfff
223fe80:c25b:dd:dd:dd06:0:d:e000/116fe80:c25b:dd:dd:dd06:0:d:efff
224fe80:c25b:dd:dd:dd06:0:d:f000/116fe80:c25b:dd:dd:dd06:0:d:ffff
225fe80:c25b:dd:dd:dd06:0:e:0/116fe80:c25b:dd:dd:dd06:0:e:fff
226fe80:c25b:dd:dd:dd06:0:e:1000/116fe80:c25b:dd:dd:dd06:0:e:1fff
227fe80:c25b:dd:dd:dd06:0:e:2000/116fe80:c25b:dd:dd:dd06:0:e:2fff
228fe80:c25b:dd:dd:dd06:0:e:3000/116fe80:c25b:dd:dd:dd06:0:e:3fff
229fe80:c25b:dd:dd:dd06:0:e:4000/116fe80:c25b:dd:dd:dd06:0:e:4fff
230fe80:c25b:dd:dd:dd06:0:e:5000/116fe80:c25b:dd:dd:dd06:0:e:5fff
231fe80:c25b:dd:dd:dd06:0:e:6000/116fe80:c25b:dd:dd:dd06:0:e:6fff
232fe80:c25b:dd:dd:dd06:0:e:7000/116fe80:c25b:dd:dd:dd06:0:e:7fff
233fe80:c25b:dd:dd:dd06:0:e:8000/116fe80:c25b:dd:dd:dd06:0:e:8fff
234fe80:c25b:dd:dd:dd06:0:e:9000/116fe80:c25b:dd:dd:dd06:0:e:9fff
235fe80:c25b:dd:dd:dd06:0:e:a000/116fe80:c25b:dd:dd:dd06:0:e:afff
236fe80:c25b:dd:dd:dd06:0:e:b000/116fe80:c25b:dd:dd:dd06:0:e:bfff
237fe80:c25b:dd:dd:dd06:0:e:c000/116fe80:c25b:dd:dd:dd06:0:e:cfff
238fe80:c25b:dd:dd:dd06:0:e:d000/116fe80:c25b:dd:dd:dd06:0:e:dfff
239fe80:c25b:dd:dd:dd06:0:e:e000/116fe80:c25b:dd:dd:dd06:0:e:efff
240fe80:c25b:dd:dd:dd06:0:e:f000/116fe80:c25b:dd:dd:dd06:0:e:ffff
241fe80:c25b:dd:dd:dd06:0:f:0/116fe80:c25b:dd:dd:dd06:0:f:fff
242fe80:c25b:dd:dd:dd06:0:f:1000/116fe80:c25b:dd:dd:dd06:0:f:1fff
243fe80:c25b:dd:dd:dd06:0:f:2000/116fe80:c25b:dd:dd:dd06:0:f:2fff
244fe80:c25b:dd:dd:dd06:0:f:3000/116fe80:c25b:dd:dd:dd06:0:f:3fff
245fe80:c25b:dd:dd:dd06:0:f:4000/116fe80:c25b:dd:dd:dd06:0:f:4fff
246fe80:c25b:dd:dd:dd06:0:f:5000/116fe80:c25b:dd:dd:dd06:0:f:5fff
247fe80:c25b:dd:dd:dd06:0:f:6000/116fe80:c25b:dd:dd:dd06:0:f:6fff
248fe80:c25b:dd:dd:dd06:0:f:7000/116fe80:c25b:dd:dd:dd06:0:f:7fff
249fe80:c25b:dd:dd:dd06:0:f:8000/116fe80:c25b:dd:dd:dd06:0:f:8fff
250fe80:c25b:dd:dd:dd06:0:f:9000/116fe80:c25b:dd:dd:dd06:0:f:9fff
251fe80:c25b:dd:dd:dd06:0:f:a000/116fe80:c25b:dd:dd:dd06:0:f:afff
252fe80:c25b:dd:dd:dd06:0:f:b000/116fe80:c25b:dd:dd:dd06:0:f:bfff
253fe80:c25b:dd:dd:dd06:0:f:c000/116fe80:c25b:dd:dd:dd06:0:f:cfff
254fe80:c25b:dd:dd:dd06:0:f:d000/116fe80:c25b:dd:dd:dd06:0:f:dfff
255fe80:c25b:dd:dd:dd06:0:f:e000/116fe80:c25b:dd:dd:dd06:0:f:efff
256fe80:c25b:dd:dd:dd06:0:f:f000/116fe80:c25b:dd:dd:dd06:0:f: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.