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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/24
Addresses2^104
/64 networks2^40
Network
fc2e:ec00::/24
First address
fc2e:ec00::
Last address
fc2e:ecff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
20,282,409,603,651,670,423,947,251,286,016 (2^104)
/64 networks (LANs)
1,099,511,627,776 (2^40)
Full form
fc2e:ec00:0000:0000:0000:0000:0000:0000
Type
Unique local (ULA) fc00::/7
Private IPv6, like RFC 1918; usually fd00::/8
Reverse DNS zone
c.e.e.2.c.f.ip6.arpa
Split into smaller subnets/36
/25 (2)/26 (4)/27 (8)/28 (16)/32 (256)/36 (4,096)/40 (65,536)

fc2e:ec00::/24 makes 4,096 subnets of /36; the first 256 are listed.

Subnets
#SubnetLast address
1fc2e:ec00::/36fc2e:ec00:fff:ffff:ffff:ffff:ffff:ffff
2fc2e:ec00:1000::/36fc2e:ec00:1fff:ffff:ffff:ffff:ffff:ffff
3fc2e:ec00:2000::/36fc2e:ec00:2fff:ffff:ffff:ffff:ffff:ffff
4fc2e:ec00:3000::/36fc2e:ec00:3fff:ffff:ffff:ffff:ffff:ffff
5fc2e:ec00:4000::/36fc2e:ec00:4fff:ffff:ffff:ffff:ffff:ffff
6fc2e:ec00:5000::/36fc2e:ec00:5fff:ffff:ffff:ffff:ffff:ffff
7fc2e:ec00:6000::/36fc2e:ec00:6fff:ffff:ffff:ffff:ffff:ffff
8fc2e:ec00:7000::/36fc2e:ec00:7fff:ffff:ffff:ffff:ffff:ffff
9fc2e:ec00:8000::/36fc2e:ec00:8fff:ffff:ffff:ffff:ffff:ffff
10fc2e:ec00:9000::/36fc2e:ec00:9fff:ffff:ffff:ffff:ffff:ffff
11fc2e:ec00:a000::/36fc2e:ec00:afff:ffff:ffff:ffff:ffff:ffff
12fc2e:ec00:b000::/36fc2e:ec00:bfff:ffff:ffff:ffff:ffff:ffff
13fc2e:ec00:c000::/36fc2e:ec00:cfff:ffff:ffff:ffff:ffff:ffff
14fc2e:ec00:d000::/36fc2e:ec00:dfff:ffff:ffff:ffff:ffff:ffff
15fc2e:ec00:e000::/36fc2e:ec00:efff:ffff:ffff:ffff:ffff:ffff
16fc2e:ec00:f000::/36fc2e:ec00:ffff:ffff:ffff:ffff:ffff:ffff
17fc2e:ec01::/36fc2e:ec01:fff:ffff:ffff:ffff:ffff:ffff
18fc2e:ec01:1000::/36fc2e:ec01:1fff:ffff:ffff:ffff:ffff:ffff
19fc2e:ec01:2000::/36fc2e:ec01:2fff:ffff:ffff:ffff:ffff:ffff
20fc2e:ec01:3000::/36fc2e:ec01:3fff:ffff:ffff:ffff:ffff:ffff
21fc2e:ec01:4000::/36fc2e:ec01:4fff:ffff:ffff:ffff:ffff:ffff
22fc2e:ec01:5000::/36fc2e:ec01:5fff:ffff:ffff:ffff:ffff:ffff
23fc2e:ec01:6000::/36fc2e:ec01:6fff:ffff:ffff:ffff:ffff:ffff
24fc2e:ec01:7000::/36fc2e:ec01:7fff:ffff:ffff:ffff:ffff:ffff
25fc2e:ec01:8000::/36fc2e:ec01:8fff:ffff:ffff:ffff:ffff:ffff
26fc2e:ec01:9000::/36fc2e:ec01:9fff:ffff:ffff:ffff:ffff:ffff
27fc2e:ec01:a000::/36fc2e:ec01:afff:ffff:ffff:ffff:ffff:ffff
28fc2e:ec01:b000::/36fc2e:ec01:bfff:ffff:ffff:ffff:ffff:ffff
29fc2e:ec01:c000::/36fc2e:ec01:cfff:ffff:ffff:ffff:ffff:ffff
30fc2e:ec01:d000::/36fc2e:ec01:dfff:ffff:ffff:ffff:ffff:ffff
31fc2e:ec01:e000::/36fc2e:ec01:efff:ffff:ffff:ffff:ffff:ffff
32fc2e:ec01:f000::/36fc2e:ec01:ffff:ffff:ffff:ffff:ffff:ffff
33fc2e:ec02::/36fc2e:ec02:fff:ffff:ffff:ffff:ffff:ffff
34fc2e:ec02:1000::/36fc2e:ec02:1fff:ffff:ffff:ffff:ffff:ffff
35fc2e:ec02:2000::/36fc2e:ec02:2fff:ffff:ffff:ffff:ffff:ffff
36fc2e:ec02:3000::/36fc2e:ec02:3fff:ffff:ffff:ffff:ffff:ffff
37fc2e:ec02:4000::/36fc2e:ec02:4fff:ffff:ffff:ffff:ffff:ffff
38fc2e:ec02:5000::/36fc2e:ec02:5fff:ffff:ffff:ffff:ffff:ffff
39fc2e:ec02:6000::/36fc2e:ec02:6fff:ffff:ffff:ffff:ffff:ffff
40fc2e:ec02:7000::/36fc2e:ec02:7fff:ffff:ffff:ffff:ffff:ffff
41fc2e:ec02:8000::/36fc2e:ec02:8fff:ffff:ffff:ffff:ffff:ffff
42fc2e:ec02:9000::/36fc2e:ec02:9fff:ffff:ffff:ffff:ffff:ffff
43fc2e:ec02:a000::/36fc2e:ec02:afff:ffff:ffff:ffff:ffff:ffff
44fc2e:ec02:b000::/36fc2e:ec02:bfff:ffff:ffff:ffff:ffff:ffff
45fc2e:ec02:c000::/36fc2e:ec02:cfff:ffff:ffff:ffff:ffff:ffff
46fc2e:ec02:d000::/36fc2e:ec02:dfff:ffff:ffff:ffff:ffff:ffff
47fc2e:ec02:e000::/36fc2e:ec02:efff:ffff:ffff:ffff:ffff:ffff
48fc2e:ec02:f000::/36fc2e:ec02:ffff:ffff:ffff:ffff:ffff:ffff
49fc2e:ec03::/36fc2e:ec03:fff:ffff:ffff:ffff:ffff:ffff
50fc2e:ec03:1000::/36fc2e:ec03:1fff:ffff:ffff:ffff:ffff:ffff
51fc2e:ec03:2000::/36fc2e:ec03:2fff:ffff:ffff:ffff:ffff:ffff
52fc2e:ec03:3000::/36fc2e:ec03:3fff:ffff:ffff:ffff:ffff:ffff
53fc2e:ec03:4000::/36fc2e:ec03:4fff:ffff:ffff:ffff:ffff:ffff
54fc2e:ec03:5000::/36fc2e:ec03:5fff:ffff:ffff:ffff:ffff:ffff
55fc2e:ec03:6000::/36fc2e:ec03:6fff:ffff:ffff:ffff:ffff:ffff
56fc2e:ec03:7000::/36fc2e:ec03:7fff:ffff:ffff:ffff:ffff:ffff
57fc2e:ec03:8000::/36fc2e:ec03:8fff:ffff:ffff:ffff:ffff:ffff
58fc2e:ec03:9000::/36fc2e:ec03:9fff:ffff:ffff:ffff:ffff:ffff
59fc2e:ec03:a000::/36fc2e:ec03:afff:ffff:ffff:ffff:ffff:ffff
60fc2e:ec03:b000::/36fc2e:ec03:bfff:ffff:ffff:ffff:ffff:ffff
61fc2e:ec03:c000::/36fc2e:ec03:cfff:ffff:ffff:ffff:ffff:ffff
62fc2e:ec03:d000::/36fc2e:ec03:dfff:ffff:ffff:ffff:ffff:ffff
63fc2e:ec03:e000::/36fc2e:ec03:efff:ffff:ffff:ffff:ffff:ffff
64fc2e:ec03:f000::/36fc2e:ec03:ffff:ffff:ffff:ffff:ffff:ffff
65fc2e:ec04::/36fc2e:ec04:fff:ffff:ffff:ffff:ffff:ffff
66fc2e:ec04:1000::/36fc2e:ec04:1fff:ffff:ffff:ffff:ffff:ffff
67fc2e:ec04:2000::/36fc2e:ec04:2fff:ffff:ffff:ffff:ffff:ffff
68fc2e:ec04:3000::/36fc2e:ec04:3fff:ffff:ffff:ffff:ffff:ffff
69fc2e:ec04:4000::/36fc2e:ec04:4fff:ffff:ffff:ffff:ffff:ffff
70fc2e:ec04:5000::/36fc2e:ec04:5fff:ffff:ffff:ffff:ffff:ffff
71fc2e:ec04:6000::/36fc2e:ec04:6fff:ffff:ffff:ffff:ffff:ffff
72fc2e:ec04:7000::/36fc2e:ec04:7fff:ffff:ffff:ffff:ffff:ffff
73fc2e:ec04:8000::/36fc2e:ec04:8fff:ffff:ffff:ffff:ffff:ffff
74fc2e:ec04:9000::/36fc2e:ec04:9fff:ffff:ffff:ffff:ffff:ffff
75fc2e:ec04:a000::/36fc2e:ec04:afff:ffff:ffff:ffff:ffff:ffff
76fc2e:ec04:b000::/36fc2e:ec04:bfff:ffff:ffff:ffff:ffff:ffff
77fc2e:ec04:c000::/36fc2e:ec04:cfff:ffff:ffff:ffff:ffff:ffff
78fc2e:ec04:d000::/36fc2e:ec04:dfff:ffff:ffff:ffff:ffff:ffff
79fc2e:ec04:e000::/36fc2e:ec04:efff:ffff:ffff:ffff:ffff:ffff
80fc2e:ec04:f000::/36fc2e:ec04:ffff:ffff:ffff:ffff:ffff:ffff
81fc2e:ec05::/36fc2e:ec05:fff:ffff:ffff:ffff:ffff:ffff
82fc2e:ec05:1000::/36fc2e:ec05:1fff:ffff:ffff:ffff:ffff:ffff
83fc2e:ec05:2000::/36fc2e:ec05:2fff:ffff:ffff:ffff:ffff:ffff
84fc2e:ec05:3000::/36fc2e:ec05:3fff:ffff:ffff:ffff:ffff:ffff
85fc2e:ec05:4000::/36fc2e:ec05:4fff:ffff:ffff:ffff:ffff:ffff
86fc2e:ec05:5000::/36fc2e:ec05:5fff:ffff:ffff:ffff:ffff:ffff
87fc2e:ec05:6000::/36fc2e:ec05:6fff:ffff:ffff:ffff:ffff:ffff
88fc2e:ec05:7000::/36fc2e:ec05:7fff:ffff:ffff:ffff:ffff:ffff
89fc2e:ec05:8000::/36fc2e:ec05:8fff:ffff:ffff:ffff:ffff:ffff
90fc2e:ec05:9000::/36fc2e:ec05:9fff:ffff:ffff:ffff:ffff:ffff
91fc2e:ec05:a000::/36fc2e:ec05:afff:ffff:ffff:ffff:ffff:ffff
92fc2e:ec05:b000::/36fc2e:ec05:bfff:ffff:ffff:ffff:ffff:ffff
93fc2e:ec05:c000::/36fc2e:ec05:cfff:ffff:ffff:ffff:ffff:ffff
94fc2e:ec05:d000::/36fc2e:ec05:dfff:ffff:ffff:ffff:ffff:ffff
95fc2e:ec05:e000::/36fc2e:ec05:efff:ffff:ffff:ffff:ffff:ffff
96fc2e:ec05:f000::/36fc2e:ec05:ffff:ffff:ffff:ffff:ffff:ffff
97fc2e:ec06::/36fc2e:ec06:fff:ffff:ffff:ffff:ffff:ffff
98fc2e:ec06:1000::/36fc2e:ec06:1fff:ffff:ffff:ffff:ffff:ffff
99fc2e:ec06:2000::/36fc2e:ec06:2fff:ffff:ffff:ffff:ffff:ffff
100fc2e:ec06:3000::/36fc2e:ec06:3fff:ffff:ffff:ffff:ffff:ffff
101fc2e:ec06:4000::/36fc2e:ec06:4fff:ffff:ffff:ffff:ffff:ffff
102fc2e:ec06:5000::/36fc2e:ec06:5fff:ffff:ffff:ffff:ffff:ffff
103fc2e:ec06:6000::/36fc2e:ec06:6fff:ffff:ffff:ffff:ffff:ffff
104fc2e:ec06:7000::/36fc2e:ec06:7fff:ffff:ffff:ffff:ffff:ffff
105fc2e:ec06:8000::/36fc2e:ec06:8fff:ffff:ffff:ffff:ffff:ffff
106fc2e:ec06:9000::/36fc2e:ec06:9fff:ffff:ffff:ffff:ffff:ffff
107fc2e:ec06:a000::/36fc2e:ec06:afff:ffff:ffff:ffff:ffff:ffff
108fc2e:ec06:b000::/36fc2e:ec06:bfff:ffff:ffff:ffff:ffff:ffff
109fc2e:ec06:c000::/36fc2e:ec06:cfff:ffff:ffff:ffff:ffff:ffff
110fc2e:ec06:d000::/36fc2e:ec06:dfff:ffff:ffff:ffff:ffff:ffff
111fc2e:ec06:e000::/36fc2e:ec06:efff:ffff:ffff:ffff:ffff:ffff
112fc2e:ec06:f000::/36fc2e:ec06:ffff:ffff:ffff:ffff:ffff:ffff
113fc2e:ec07::/36fc2e:ec07:fff:ffff:ffff:ffff:ffff:ffff
114fc2e:ec07:1000::/36fc2e:ec07:1fff:ffff:ffff:ffff:ffff:ffff
115fc2e:ec07:2000::/36fc2e:ec07:2fff:ffff:ffff:ffff:ffff:ffff
116fc2e:ec07:3000::/36fc2e:ec07:3fff:ffff:ffff:ffff:ffff:ffff
117fc2e:ec07:4000::/36fc2e:ec07:4fff:ffff:ffff:ffff:ffff:ffff
118fc2e:ec07:5000::/36fc2e:ec07:5fff:ffff:ffff:ffff:ffff:ffff
119fc2e:ec07:6000::/36fc2e:ec07:6fff:ffff:ffff:ffff:ffff:ffff
120fc2e:ec07:7000::/36fc2e:ec07:7fff:ffff:ffff:ffff:ffff:ffff
121fc2e:ec07:8000::/36fc2e:ec07:8fff:ffff:ffff:ffff:ffff:ffff
122fc2e:ec07:9000::/36fc2e:ec07:9fff:ffff:ffff:ffff:ffff:ffff
123fc2e:ec07:a000::/36fc2e:ec07:afff:ffff:ffff:ffff:ffff:ffff
124fc2e:ec07:b000::/36fc2e:ec07:bfff:ffff:ffff:ffff:ffff:ffff
125fc2e:ec07:c000::/36fc2e:ec07:cfff:ffff:ffff:ffff:ffff:ffff
126fc2e:ec07:d000::/36fc2e:ec07:dfff:ffff:ffff:ffff:ffff:ffff
127fc2e:ec07:e000::/36fc2e:ec07:efff:ffff:ffff:ffff:ffff:ffff
128fc2e:ec07:f000::/36fc2e:ec07:ffff:ffff:ffff:ffff:ffff:ffff
129fc2e:ec08::/36fc2e:ec08:fff:ffff:ffff:ffff:ffff:ffff
130fc2e:ec08:1000::/36fc2e:ec08:1fff:ffff:ffff:ffff:ffff:ffff
131fc2e:ec08:2000::/36fc2e:ec08:2fff:ffff:ffff:ffff:ffff:ffff
132fc2e:ec08:3000::/36fc2e:ec08:3fff:ffff:ffff:ffff:ffff:ffff
133fc2e:ec08:4000::/36fc2e:ec08:4fff:ffff:ffff:ffff:ffff:ffff
134fc2e:ec08:5000::/36fc2e:ec08:5fff:ffff:ffff:ffff:ffff:ffff
135fc2e:ec08:6000::/36fc2e:ec08:6fff:ffff:ffff:ffff:ffff:ffff
136fc2e:ec08:7000::/36fc2e:ec08:7fff:ffff:ffff:ffff:ffff:ffff
137fc2e:ec08:8000::/36fc2e:ec08:8fff:ffff:ffff:ffff:ffff:ffff
138fc2e:ec08:9000::/36fc2e:ec08:9fff:ffff:ffff:ffff:ffff:ffff
139fc2e:ec08:a000::/36fc2e:ec08:afff:ffff:ffff:ffff:ffff:ffff
140fc2e:ec08:b000::/36fc2e:ec08:bfff:ffff:ffff:ffff:ffff:ffff
141fc2e:ec08:c000::/36fc2e:ec08:cfff:ffff:ffff:ffff:ffff:ffff
142fc2e:ec08:d000::/36fc2e:ec08:dfff:ffff:ffff:ffff:ffff:ffff
143fc2e:ec08:e000::/36fc2e:ec08:efff:ffff:ffff:ffff:ffff:ffff
144fc2e:ec08:f000::/36fc2e:ec08:ffff:ffff:ffff:ffff:ffff:ffff
145fc2e:ec09::/36fc2e:ec09:fff:ffff:ffff:ffff:ffff:ffff
146fc2e:ec09:1000::/36fc2e:ec09:1fff:ffff:ffff:ffff:ffff:ffff
147fc2e:ec09:2000::/36fc2e:ec09:2fff:ffff:ffff:ffff:ffff:ffff
148fc2e:ec09:3000::/36fc2e:ec09:3fff:ffff:ffff:ffff:ffff:ffff
149fc2e:ec09:4000::/36fc2e:ec09:4fff:ffff:ffff:ffff:ffff:ffff
150fc2e:ec09:5000::/36fc2e:ec09:5fff:ffff:ffff:ffff:ffff:ffff
151fc2e:ec09:6000::/36fc2e:ec09:6fff:ffff:ffff:ffff:ffff:ffff
152fc2e:ec09:7000::/36fc2e:ec09:7fff:ffff:ffff:ffff:ffff:ffff
153fc2e:ec09:8000::/36fc2e:ec09:8fff:ffff:ffff:ffff:ffff:ffff
154fc2e:ec09:9000::/36fc2e:ec09:9fff:ffff:ffff:ffff:ffff:ffff
155fc2e:ec09:a000::/36fc2e:ec09:afff:ffff:ffff:ffff:ffff:ffff
156fc2e:ec09:b000::/36fc2e:ec09:bfff:ffff:ffff:ffff:ffff:ffff
157fc2e:ec09:c000::/36fc2e:ec09:cfff:ffff:ffff:ffff:ffff:ffff
158fc2e:ec09:d000::/36fc2e:ec09:dfff:ffff:ffff:ffff:ffff:ffff
159fc2e:ec09:e000::/36fc2e:ec09:efff:ffff:ffff:ffff:ffff:ffff
160fc2e:ec09:f000::/36fc2e:ec09:ffff:ffff:ffff:ffff:ffff:ffff
161fc2e:ec0a::/36fc2e:ec0a:fff:ffff:ffff:ffff:ffff:ffff
162fc2e:ec0a:1000::/36fc2e:ec0a:1fff:ffff:ffff:ffff:ffff:ffff
163fc2e:ec0a:2000::/36fc2e:ec0a:2fff:ffff:ffff:ffff:ffff:ffff
164fc2e:ec0a:3000::/36fc2e:ec0a:3fff:ffff:ffff:ffff:ffff:ffff
165fc2e:ec0a:4000::/36fc2e:ec0a:4fff:ffff:ffff:ffff:ffff:ffff
166fc2e:ec0a:5000::/36fc2e:ec0a:5fff:ffff:ffff:ffff:ffff:ffff
167fc2e:ec0a:6000::/36fc2e:ec0a:6fff:ffff:ffff:ffff:ffff:ffff
168fc2e:ec0a:7000::/36fc2e:ec0a:7fff:ffff:ffff:ffff:ffff:ffff
169fc2e:ec0a:8000::/36fc2e:ec0a:8fff:ffff:ffff:ffff:ffff:ffff
170fc2e:ec0a:9000::/36fc2e:ec0a:9fff:ffff:ffff:ffff:ffff:ffff
171fc2e:ec0a:a000::/36fc2e:ec0a:afff:ffff:ffff:ffff:ffff:ffff
172fc2e:ec0a:b000::/36fc2e:ec0a:bfff:ffff:ffff:ffff:ffff:ffff
173fc2e:ec0a:c000::/36fc2e:ec0a:cfff:ffff:ffff:ffff:ffff:ffff
174fc2e:ec0a:d000::/36fc2e:ec0a:dfff:ffff:ffff:ffff:ffff:ffff
175fc2e:ec0a:e000::/36fc2e:ec0a:efff:ffff:ffff:ffff:ffff:ffff
176fc2e:ec0a:f000::/36fc2e:ec0a:ffff:ffff:ffff:ffff:ffff:ffff
177fc2e:ec0b::/36fc2e:ec0b:fff:ffff:ffff:ffff:ffff:ffff
178fc2e:ec0b:1000::/36fc2e:ec0b:1fff:ffff:ffff:ffff:ffff:ffff
179fc2e:ec0b:2000::/36fc2e:ec0b:2fff:ffff:ffff:ffff:ffff:ffff
180fc2e:ec0b:3000::/36fc2e:ec0b:3fff:ffff:ffff:ffff:ffff:ffff
181fc2e:ec0b:4000::/36fc2e:ec0b:4fff:ffff:ffff:ffff:ffff:ffff
182fc2e:ec0b:5000::/36fc2e:ec0b:5fff:ffff:ffff:ffff:ffff:ffff
183fc2e:ec0b:6000::/36fc2e:ec0b:6fff:ffff:ffff:ffff:ffff:ffff
184fc2e:ec0b:7000::/36fc2e:ec0b:7fff:ffff:ffff:ffff:ffff:ffff
185fc2e:ec0b:8000::/36fc2e:ec0b:8fff:ffff:ffff:ffff:ffff:ffff
186fc2e:ec0b:9000::/36fc2e:ec0b:9fff:ffff:ffff:ffff:ffff:ffff
187fc2e:ec0b:a000::/36fc2e:ec0b:afff:ffff:ffff:ffff:ffff:ffff
188fc2e:ec0b:b000::/36fc2e:ec0b:bfff:ffff:ffff:ffff:ffff:ffff
189fc2e:ec0b:c000::/36fc2e:ec0b:cfff:ffff:ffff:ffff:ffff:ffff
190fc2e:ec0b:d000::/36fc2e:ec0b:dfff:ffff:ffff:ffff:ffff:ffff
191fc2e:ec0b:e000::/36fc2e:ec0b:efff:ffff:ffff:ffff:ffff:ffff
192fc2e:ec0b:f000::/36fc2e:ec0b:ffff:ffff:ffff:ffff:ffff:ffff
193fc2e:ec0c::/36fc2e:ec0c:fff:ffff:ffff:ffff:ffff:ffff
194fc2e:ec0c:1000::/36fc2e:ec0c:1fff:ffff:ffff:ffff:ffff:ffff
195fc2e:ec0c:2000::/36fc2e:ec0c:2fff:ffff:ffff:ffff:ffff:ffff
196fc2e:ec0c:3000::/36fc2e:ec0c:3fff:ffff:ffff:ffff:ffff:ffff
197fc2e:ec0c:4000::/36fc2e:ec0c:4fff:ffff:ffff:ffff:ffff:ffff
198fc2e:ec0c:5000::/36fc2e:ec0c:5fff:ffff:ffff:ffff:ffff:ffff
199fc2e:ec0c:6000::/36fc2e:ec0c:6fff:ffff:ffff:ffff:ffff:ffff
200fc2e:ec0c:7000::/36fc2e:ec0c:7fff:ffff:ffff:ffff:ffff:ffff
201fc2e:ec0c:8000::/36fc2e:ec0c:8fff:ffff:ffff:ffff:ffff:ffff
202fc2e:ec0c:9000::/36fc2e:ec0c:9fff:ffff:ffff:ffff:ffff:ffff
203fc2e:ec0c:a000::/36fc2e:ec0c:afff:ffff:ffff:ffff:ffff:ffff
204fc2e:ec0c:b000::/36fc2e:ec0c:bfff:ffff:ffff:ffff:ffff:ffff
205fc2e:ec0c:c000::/36fc2e:ec0c:cfff:ffff:ffff:ffff:ffff:ffff
206fc2e:ec0c:d000::/36fc2e:ec0c:dfff:ffff:ffff:ffff:ffff:ffff
207fc2e:ec0c:e000::/36fc2e:ec0c:efff:ffff:ffff:ffff:ffff:ffff
208fc2e:ec0c:f000::/36fc2e:ec0c:ffff:ffff:ffff:ffff:ffff:ffff
209fc2e:ec0d::/36fc2e:ec0d:fff:ffff:ffff:ffff:ffff:ffff
210fc2e:ec0d:1000::/36fc2e:ec0d:1fff:ffff:ffff:ffff:ffff:ffff
211fc2e:ec0d:2000::/36fc2e:ec0d:2fff:ffff:ffff:ffff:ffff:ffff
212fc2e:ec0d:3000::/36fc2e:ec0d:3fff:ffff:ffff:ffff:ffff:ffff
213fc2e:ec0d:4000::/36fc2e:ec0d:4fff:ffff:ffff:ffff:ffff:ffff
214fc2e:ec0d:5000::/36fc2e:ec0d:5fff:ffff:ffff:ffff:ffff:ffff
215fc2e:ec0d:6000::/36fc2e:ec0d:6fff:ffff:ffff:ffff:ffff:ffff
216fc2e:ec0d:7000::/36fc2e:ec0d:7fff:ffff:ffff:ffff:ffff:ffff
217fc2e:ec0d:8000::/36fc2e:ec0d:8fff:ffff:ffff:ffff:ffff:ffff
218fc2e:ec0d:9000::/36fc2e:ec0d:9fff:ffff:ffff:ffff:ffff:ffff
219fc2e:ec0d:a000::/36fc2e:ec0d:afff:ffff:ffff:ffff:ffff:ffff
220fc2e:ec0d:b000::/36fc2e:ec0d:bfff:ffff:ffff:ffff:ffff:ffff
221fc2e:ec0d:c000::/36fc2e:ec0d:cfff:ffff:ffff:ffff:ffff:ffff
222fc2e:ec0d:d000::/36fc2e:ec0d:dfff:ffff:ffff:ffff:ffff:ffff
223fc2e:ec0d:e000::/36fc2e:ec0d:efff:ffff:ffff:ffff:ffff:ffff
224fc2e:ec0d:f000::/36fc2e:ec0d:ffff:ffff:ffff:ffff:ffff:ffff
225fc2e:ec0e::/36fc2e:ec0e:fff:ffff:ffff:ffff:ffff:ffff
226fc2e:ec0e:1000::/36fc2e:ec0e:1fff:ffff:ffff:ffff:ffff:ffff
227fc2e:ec0e:2000::/36fc2e:ec0e:2fff:ffff:ffff:ffff:ffff:ffff
228fc2e:ec0e:3000::/36fc2e:ec0e:3fff:ffff:ffff:ffff:ffff:ffff
229fc2e:ec0e:4000::/36fc2e:ec0e:4fff:ffff:ffff:ffff:ffff:ffff
230fc2e:ec0e:5000::/36fc2e:ec0e:5fff:ffff:ffff:ffff:ffff:ffff
231fc2e:ec0e:6000::/36fc2e:ec0e:6fff:ffff:ffff:ffff:ffff:ffff
232fc2e:ec0e:7000::/36fc2e:ec0e:7fff:ffff:ffff:ffff:ffff:ffff
233fc2e:ec0e:8000::/36fc2e:ec0e:8fff:ffff:ffff:ffff:ffff:ffff
234fc2e:ec0e:9000::/36fc2e:ec0e:9fff:ffff:ffff:ffff:ffff:ffff
235fc2e:ec0e:a000::/36fc2e:ec0e:afff:ffff:ffff:ffff:ffff:ffff
236fc2e:ec0e:b000::/36fc2e:ec0e:bfff:ffff:ffff:ffff:ffff:ffff
237fc2e:ec0e:c000::/36fc2e:ec0e:cfff:ffff:ffff:ffff:ffff:ffff
238fc2e:ec0e:d000::/36fc2e:ec0e:dfff:ffff:ffff:ffff:ffff:ffff
239fc2e:ec0e:e000::/36fc2e:ec0e:efff:ffff:ffff:ffff:ffff:ffff
240fc2e:ec0e:f000::/36fc2e:ec0e:ffff:ffff:ffff:ffff:ffff:ffff
241fc2e:ec0f::/36fc2e:ec0f:fff:ffff:ffff:ffff:ffff:ffff
242fc2e:ec0f:1000::/36fc2e:ec0f:1fff:ffff:ffff:ffff:ffff:ffff
243fc2e:ec0f:2000::/36fc2e:ec0f:2fff:ffff:ffff:ffff:ffff:ffff
244fc2e:ec0f:3000::/36fc2e:ec0f:3fff:ffff:ffff:ffff:ffff:ffff
245fc2e:ec0f:4000::/36fc2e:ec0f:4fff:ffff:ffff:ffff:ffff:ffff
246fc2e:ec0f:5000::/36fc2e:ec0f:5fff:ffff:ffff:ffff:ffff:ffff
247fc2e:ec0f:6000::/36fc2e:ec0f:6fff:ffff:ffff:ffff:ffff:ffff
248fc2e:ec0f:7000::/36fc2e:ec0f:7fff:ffff:ffff:ffff:ffff:ffff
249fc2e:ec0f:8000::/36fc2e:ec0f:8fff:ffff:ffff:ffff:ffff:ffff
250fc2e:ec0f:9000::/36fc2e:ec0f:9fff:ffff:ffff:ffff:ffff:ffff
251fc2e:ec0f:a000::/36fc2e:ec0f:afff:ffff:ffff:ffff:ffff:ffff
252fc2e:ec0f:b000::/36fc2e:ec0f:bfff:ffff:ffff:ffff:ffff:ffff
253fc2e:ec0f:c000::/36fc2e:ec0f:cfff:ffff:ffff:ffff:ffff:ffff
254fc2e:ec0f:d000::/36fc2e:ec0f:dfff:ffff:ffff:ffff:ffff:ffff
255fc2e:ec0f:e000::/36fc2e:ec0f:efff:ffff:ffff:ffff:ffff:ffff
256fc2e:ec0f:f000::/36fc2e:ec0f: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.