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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/11
Addresses2^117
/64 networks2^53
Network
fc60::/11
First address
fc60::
Last address
fc7f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
166,153,499,473,114,484,112,975,882,535,043,072 (2^117)
/64 networks (LANs)
9,007,199,254,740,992 (2^53)
Full form
fc60:0000:0000:0000:0000:0000:0000:0000
Type
Unique local (ULA) fc00::/7
Private IPv6, like RFC 1918; usually fd00::/8
Reverse DNS zones
6.c.f.ip6.arpa
7.c.f.ip6.arpa
/11 is not on a 4-bit boundary, so it takes 2 /12 zones.
Split into smaller subnets/20
/12 (2)/13 (4)/14 (8)/15 (16)/16 (32)/20 (512)/24 (8,192)

fc60::/11 makes 512 subnets of /20; the first 256 are listed.

Subnets
#SubnetLast address
1fc60::/20fc60:fff:ffff:ffff:ffff:ffff:ffff:ffff
2fc60:1000::/20fc60:1fff:ffff:ffff:ffff:ffff:ffff:ffff
3fc60:2000::/20fc60:2fff:ffff:ffff:ffff:ffff:ffff:ffff
4fc60:3000::/20fc60:3fff:ffff:ffff:ffff:ffff:ffff:ffff
5fc60:4000::/20fc60:4fff:ffff:ffff:ffff:ffff:ffff:ffff
6fc60:5000::/20fc60:5fff:ffff:ffff:ffff:ffff:ffff:ffff
7fc60:6000::/20fc60:6fff:ffff:ffff:ffff:ffff:ffff:ffff
8fc60:7000::/20fc60:7fff:ffff:ffff:ffff:ffff:ffff:ffff
9fc60:8000::/20fc60:8fff:ffff:ffff:ffff:ffff:ffff:ffff
10fc60:9000::/20fc60:9fff:ffff:ffff:ffff:ffff:ffff:ffff
11fc60:a000::/20fc60:afff:ffff:ffff:ffff:ffff:ffff:ffff
12fc60:b000::/20fc60:bfff:ffff:ffff:ffff:ffff:ffff:ffff
13fc60:c000::/20fc60:cfff:ffff:ffff:ffff:ffff:ffff:ffff
14fc60:d000::/20fc60:dfff:ffff:ffff:ffff:ffff:ffff:ffff
15fc60:e000::/20fc60:efff:ffff:ffff:ffff:ffff:ffff:ffff
16fc60:f000::/20fc60:ffff:ffff:ffff:ffff:ffff:ffff:ffff
17fc61::/20fc61:fff:ffff:ffff:ffff:ffff:ffff:ffff
18fc61:1000::/20fc61:1fff:ffff:ffff:ffff:ffff:ffff:ffff
19fc61:2000::/20fc61:2fff:ffff:ffff:ffff:ffff:ffff:ffff
20fc61:3000::/20fc61:3fff:ffff:ffff:ffff:ffff:ffff:ffff
21fc61:4000::/20fc61:4fff:ffff:ffff:ffff:ffff:ffff:ffff
22fc61:5000::/20fc61:5fff:ffff:ffff:ffff:ffff:ffff:ffff
23fc61:6000::/20fc61:6fff:ffff:ffff:ffff:ffff:ffff:ffff
24fc61:7000::/20fc61:7fff:ffff:ffff:ffff:ffff:ffff:ffff
25fc61:8000::/20fc61:8fff:ffff:ffff:ffff:ffff:ffff:ffff
26fc61:9000::/20fc61:9fff:ffff:ffff:ffff:ffff:ffff:ffff
27fc61:a000::/20fc61:afff:ffff:ffff:ffff:ffff:ffff:ffff
28fc61:b000::/20fc61:bfff:ffff:ffff:ffff:ffff:ffff:ffff
29fc61:c000::/20fc61:cfff:ffff:ffff:ffff:ffff:ffff:ffff
30fc61:d000::/20fc61:dfff:ffff:ffff:ffff:ffff:ffff:ffff
31fc61:e000::/20fc61:efff:ffff:ffff:ffff:ffff:ffff:ffff
32fc61:f000::/20fc61:ffff:ffff:ffff:ffff:ffff:ffff:ffff
33fc62::/20fc62:fff:ffff:ffff:ffff:ffff:ffff:ffff
34fc62:1000::/20fc62:1fff:ffff:ffff:ffff:ffff:ffff:ffff
35fc62:2000::/20fc62:2fff:ffff:ffff:ffff:ffff:ffff:ffff
36fc62:3000::/20fc62:3fff:ffff:ffff:ffff:ffff:ffff:ffff
37fc62:4000::/20fc62:4fff:ffff:ffff:ffff:ffff:ffff:ffff
38fc62:5000::/20fc62:5fff:ffff:ffff:ffff:ffff:ffff:ffff
39fc62:6000::/20fc62:6fff:ffff:ffff:ffff:ffff:ffff:ffff
40fc62:7000::/20fc62:7fff:ffff:ffff:ffff:ffff:ffff:ffff
41fc62:8000::/20fc62:8fff:ffff:ffff:ffff:ffff:ffff:ffff
42fc62:9000::/20fc62:9fff:ffff:ffff:ffff:ffff:ffff:ffff
43fc62:a000::/20fc62:afff:ffff:ffff:ffff:ffff:ffff:ffff
44fc62:b000::/20fc62:bfff:ffff:ffff:ffff:ffff:ffff:ffff
45fc62:c000::/20fc62:cfff:ffff:ffff:ffff:ffff:ffff:ffff
46fc62:d000::/20fc62:dfff:ffff:ffff:ffff:ffff:ffff:ffff
47fc62:e000::/20fc62:efff:ffff:ffff:ffff:ffff:ffff:ffff
48fc62:f000::/20fc62:ffff:ffff:ffff:ffff:ffff:ffff:ffff
49fc63::/20fc63:fff:ffff:ffff:ffff:ffff:ffff:ffff
50fc63:1000::/20fc63:1fff:ffff:ffff:ffff:ffff:ffff:ffff
51fc63:2000::/20fc63:2fff:ffff:ffff:ffff:ffff:ffff:ffff
52fc63:3000::/20fc63:3fff:ffff:ffff:ffff:ffff:ffff:ffff
53fc63:4000::/20fc63:4fff:ffff:ffff:ffff:ffff:ffff:ffff
54fc63:5000::/20fc63:5fff:ffff:ffff:ffff:ffff:ffff:ffff
55fc63:6000::/20fc63:6fff:ffff:ffff:ffff:ffff:ffff:ffff
56fc63:7000::/20fc63:7fff:ffff:ffff:ffff:ffff:ffff:ffff
57fc63:8000::/20fc63:8fff:ffff:ffff:ffff:ffff:ffff:ffff
58fc63:9000::/20fc63:9fff:ffff:ffff:ffff:ffff:ffff:ffff
59fc63:a000::/20fc63:afff:ffff:ffff:ffff:ffff:ffff:ffff
60fc63:b000::/20fc63:bfff:ffff:ffff:ffff:ffff:ffff:ffff
61fc63:c000::/20fc63:cfff:ffff:ffff:ffff:ffff:ffff:ffff
62fc63:d000::/20fc63:dfff:ffff:ffff:ffff:ffff:ffff:ffff
63fc63:e000::/20fc63:efff:ffff:ffff:ffff:ffff:ffff:ffff
64fc63:f000::/20fc63:ffff:ffff:ffff:ffff:ffff:ffff:ffff
65fc64::/20fc64:fff:ffff:ffff:ffff:ffff:ffff:ffff
66fc64:1000::/20fc64:1fff:ffff:ffff:ffff:ffff:ffff:ffff
67fc64:2000::/20fc64:2fff:ffff:ffff:ffff:ffff:ffff:ffff
68fc64:3000::/20fc64:3fff:ffff:ffff:ffff:ffff:ffff:ffff
69fc64:4000::/20fc64:4fff:ffff:ffff:ffff:ffff:ffff:ffff
70fc64:5000::/20fc64:5fff:ffff:ffff:ffff:ffff:ffff:ffff
71fc64:6000::/20fc64:6fff:ffff:ffff:ffff:ffff:ffff:ffff
72fc64:7000::/20fc64:7fff:ffff:ffff:ffff:ffff:ffff:ffff
73fc64:8000::/20fc64:8fff:ffff:ffff:ffff:ffff:ffff:ffff
74fc64:9000::/20fc64:9fff:ffff:ffff:ffff:ffff:ffff:ffff
75fc64:a000::/20fc64:afff:ffff:ffff:ffff:ffff:ffff:ffff
76fc64:b000::/20fc64:bfff:ffff:ffff:ffff:ffff:ffff:ffff
77fc64:c000::/20fc64:cfff:ffff:ffff:ffff:ffff:ffff:ffff
78fc64:d000::/20fc64:dfff:ffff:ffff:ffff:ffff:ffff:ffff
79fc64:e000::/20fc64:efff:ffff:ffff:ffff:ffff:ffff:ffff
80fc64:f000::/20fc64:ffff:ffff:ffff:ffff:ffff:ffff:ffff
81fc65::/20fc65:fff:ffff:ffff:ffff:ffff:ffff:ffff
82fc65:1000::/20fc65:1fff:ffff:ffff:ffff:ffff:ffff:ffff
83fc65:2000::/20fc65:2fff:ffff:ffff:ffff:ffff:ffff:ffff
84fc65:3000::/20fc65:3fff:ffff:ffff:ffff:ffff:ffff:ffff
85fc65:4000::/20fc65:4fff:ffff:ffff:ffff:ffff:ffff:ffff
86fc65:5000::/20fc65:5fff:ffff:ffff:ffff:ffff:ffff:ffff
87fc65:6000::/20fc65:6fff:ffff:ffff:ffff:ffff:ffff:ffff
88fc65:7000::/20fc65:7fff:ffff:ffff:ffff:ffff:ffff:ffff
89fc65:8000::/20fc65:8fff:ffff:ffff:ffff:ffff:ffff:ffff
90fc65:9000::/20fc65:9fff:ffff:ffff:ffff:ffff:ffff:ffff
91fc65:a000::/20fc65:afff:ffff:ffff:ffff:ffff:ffff:ffff
92fc65:b000::/20fc65:bfff:ffff:ffff:ffff:ffff:ffff:ffff
93fc65:c000::/20fc65:cfff:ffff:ffff:ffff:ffff:ffff:ffff
94fc65:d000::/20fc65:dfff:ffff:ffff:ffff:ffff:ffff:ffff
95fc65:e000::/20fc65:efff:ffff:ffff:ffff:ffff:ffff:ffff
96fc65:f000::/20fc65:ffff:ffff:ffff:ffff:ffff:ffff:ffff
97fc66::/20fc66:fff:ffff:ffff:ffff:ffff:ffff:ffff
98fc66:1000::/20fc66:1fff:ffff:ffff:ffff:ffff:ffff:ffff
99fc66:2000::/20fc66:2fff:ffff:ffff:ffff:ffff:ffff:ffff
100fc66:3000::/20fc66:3fff:ffff:ffff:ffff:ffff:ffff:ffff
101fc66:4000::/20fc66:4fff:ffff:ffff:ffff:ffff:ffff:ffff
102fc66:5000::/20fc66:5fff:ffff:ffff:ffff:ffff:ffff:ffff
103fc66:6000::/20fc66:6fff:ffff:ffff:ffff:ffff:ffff:ffff
104fc66:7000::/20fc66:7fff:ffff:ffff:ffff:ffff:ffff:ffff
105fc66:8000::/20fc66:8fff:ffff:ffff:ffff:ffff:ffff:ffff
106fc66:9000::/20fc66:9fff:ffff:ffff:ffff:ffff:ffff:ffff
107fc66:a000::/20fc66:afff:ffff:ffff:ffff:ffff:ffff:ffff
108fc66:b000::/20fc66:bfff:ffff:ffff:ffff:ffff:ffff:ffff
109fc66:c000::/20fc66:cfff:ffff:ffff:ffff:ffff:ffff:ffff
110fc66:d000::/20fc66:dfff:ffff:ffff:ffff:ffff:ffff:ffff
111fc66:e000::/20fc66:efff:ffff:ffff:ffff:ffff:ffff:ffff
112fc66:f000::/20fc66:ffff:ffff:ffff:ffff:ffff:ffff:ffff
113fc67::/20fc67:fff:ffff:ffff:ffff:ffff:ffff:ffff
114fc67:1000::/20fc67:1fff:ffff:ffff:ffff:ffff:ffff:ffff
115fc67:2000::/20fc67:2fff:ffff:ffff:ffff:ffff:ffff:ffff
116fc67:3000::/20fc67:3fff:ffff:ffff:ffff:ffff:ffff:ffff
117fc67:4000::/20fc67:4fff:ffff:ffff:ffff:ffff:ffff:ffff
118fc67:5000::/20fc67:5fff:ffff:ffff:ffff:ffff:ffff:ffff
119fc67:6000::/20fc67:6fff:ffff:ffff:ffff:ffff:ffff:ffff
120fc67:7000::/20fc67:7fff:ffff:ffff:ffff:ffff:ffff:ffff
121fc67:8000::/20fc67:8fff:ffff:ffff:ffff:ffff:ffff:ffff
122fc67:9000::/20fc67:9fff:ffff:ffff:ffff:ffff:ffff:ffff
123fc67:a000::/20fc67:afff:ffff:ffff:ffff:ffff:ffff:ffff
124fc67:b000::/20fc67:bfff:ffff:ffff:ffff:ffff:ffff:ffff
125fc67:c000::/20fc67:cfff:ffff:ffff:ffff:ffff:ffff:ffff
126fc67:d000::/20fc67:dfff:ffff:ffff:ffff:ffff:ffff:ffff
127fc67:e000::/20fc67:efff:ffff:ffff:ffff:ffff:ffff:ffff
128fc67:f000::/20fc67:ffff:ffff:ffff:ffff:ffff:ffff:ffff
129fc68::/20fc68:fff:ffff:ffff:ffff:ffff:ffff:ffff
130fc68:1000::/20fc68:1fff:ffff:ffff:ffff:ffff:ffff:ffff
131fc68:2000::/20fc68:2fff:ffff:ffff:ffff:ffff:ffff:ffff
132fc68:3000::/20fc68:3fff:ffff:ffff:ffff:ffff:ffff:ffff
133fc68:4000::/20fc68:4fff:ffff:ffff:ffff:ffff:ffff:ffff
134fc68:5000::/20fc68:5fff:ffff:ffff:ffff:ffff:ffff:ffff
135fc68:6000::/20fc68:6fff:ffff:ffff:ffff:ffff:ffff:ffff
136fc68:7000::/20fc68:7fff:ffff:ffff:ffff:ffff:ffff:ffff
137fc68:8000::/20fc68:8fff:ffff:ffff:ffff:ffff:ffff:ffff
138fc68:9000::/20fc68:9fff:ffff:ffff:ffff:ffff:ffff:ffff
139fc68:a000::/20fc68:afff:ffff:ffff:ffff:ffff:ffff:ffff
140fc68:b000::/20fc68:bfff:ffff:ffff:ffff:ffff:ffff:ffff
141fc68:c000::/20fc68:cfff:ffff:ffff:ffff:ffff:ffff:ffff
142fc68:d000::/20fc68:dfff:ffff:ffff:ffff:ffff:ffff:ffff
143fc68:e000::/20fc68:efff:ffff:ffff:ffff:ffff:ffff:ffff
144fc68:f000::/20fc68:ffff:ffff:ffff:ffff:ffff:ffff:ffff
145fc69::/20fc69:fff:ffff:ffff:ffff:ffff:ffff:ffff
146fc69:1000::/20fc69:1fff:ffff:ffff:ffff:ffff:ffff:ffff
147fc69:2000::/20fc69:2fff:ffff:ffff:ffff:ffff:ffff:ffff
148fc69:3000::/20fc69:3fff:ffff:ffff:ffff:ffff:ffff:ffff
149fc69:4000::/20fc69:4fff:ffff:ffff:ffff:ffff:ffff:ffff
150fc69:5000::/20fc69:5fff:ffff:ffff:ffff:ffff:ffff:ffff
151fc69:6000::/20fc69:6fff:ffff:ffff:ffff:ffff:ffff:ffff
152fc69:7000::/20fc69:7fff:ffff:ffff:ffff:ffff:ffff:ffff
153fc69:8000::/20fc69:8fff:ffff:ffff:ffff:ffff:ffff:ffff
154fc69:9000::/20fc69:9fff:ffff:ffff:ffff:ffff:ffff:ffff
155fc69:a000::/20fc69:afff:ffff:ffff:ffff:ffff:ffff:ffff
156fc69:b000::/20fc69:bfff:ffff:ffff:ffff:ffff:ffff:ffff
157fc69:c000::/20fc69:cfff:ffff:ffff:ffff:ffff:ffff:ffff
158fc69:d000::/20fc69:dfff:ffff:ffff:ffff:ffff:ffff:ffff
159fc69:e000::/20fc69:efff:ffff:ffff:ffff:ffff:ffff:ffff
160fc69:f000::/20fc69:ffff:ffff:ffff:ffff:ffff:ffff:ffff
161fc6a::/20fc6a:fff:ffff:ffff:ffff:ffff:ffff:ffff
162fc6a:1000::/20fc6a:1fff:ffff:ffff:ffff:ffff:ffff:ffff
163fc6a:2000::/20fc6a:2fff:ffff:ffff:ffff:ffff:ffff:ffff
164fc6a:3000::/20fc6a:3fff:ffff:ffff:ffff:ffff:ffff:ffff
165fc6a:4000::/20fc6a:4fff:ffff:ffff:ffff:ffff:ffff:ffff
166fc6a:5000::/20fc6a:5fff:ffff:ffff:ffff:ffff:ffff:ffff
167fc6a:6000::/20fc6a:6fff:ffff:ffff:ffff:ffff:ffff:ffff
168fc6a:7000::/20fc6a:7fff:ffff:ffff:ffff:ffff:ffff:ffff
169fc6a:8000::/20fc6a:8fff:ffff:ffff:ffff:ffff:ffff:ffff
170fc6a:9000::/20fc6a:9fff:ffff:ffff:ffff:ffff:ffff:ffff
171fc6a:a000::/20fc6a:afff:ffff:ffff:ffff:ffff:ffff:ffff
172fc6a:b000::/20fc6a:bfff:ffff:ffff:ffff:ffff:ffff:ffff
173fc6a:c000::/20fc6a:cfff:ffff:ffff:ffff:ffff:ffff:ffff
174fc6a:d000::/20fc6a:dfff:ffff:ffff:ffff:ffff:ffff:ffff
175fc6a:e000::/20fc6a:efff:ffff:ffff:ffff:ffff:ffff:ffff
176fc6a:f000::/20fc6a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
177fc6b::/20fc6b:fff:ffff:ffff:ffff:ffff:ffff:ffff
178fc6b:1000::/20fc6b:1fff:ffff:ffff:ffff:ffff:ffff:ffff
179fc6b:2000::/20fc6b:2fff:ffff:ffff:ffff:ffff:ffff:ffff
180fc6b:3000::/20fc6b:3fff:ffff:ffff:ffff:ffff:ffff:ffff
181fc6b:4000::/20fc6b:4fff:ffff:ffff:ffff:ffff:ffff:ffff
182fc6b:5000::/20fc6b:5fff:ffff:ffff:ffff:ffff:ffff:ffff
183fc6b:6000::/20fc6b:6fff:ffff:ffff:ffff:ffff:ffff:ffff
184fc6b:7000::/20fc6b:7fff:ffff:ffff:ffff:ffff:ffff:ffff
185fc6b:8000::/20fc6b:8fff:ffff:ffff:ffff:ffff:ffff:ffff
186fc6b:9000::/20fc6b:9fff:ffff:ffff:ffff:ffff:ffff:ffff
187fc6b:a000::/20fc6b:afff:ffff:ffff:ffff:ffff:ffff:ffff
188fc6b:b000::/20fc6b:bfff:ffff:ffff:ffff:ffff:ffff:ffff
189fc6b:c000::/20fc6b:cfff:ffff:ffff:ffff:ffff:ffff:ffff
190fc6b:d000::/20fc6b:dfff:ffff:ffff:ffff:ffff:ffff:ffff
191fc6b:e000::/20fc6b:efff:ffff:ffff:ffff:ffff:ffff:ffff
192fc6b:f000::/20fc6b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
193fc6c::/20fc6c:fff:ffff:ffff:ffff:ffff:ffff:ffff
194fc6c:1000::/20fc6c:1fff:ffff:ffff:ffff:ffff:ffff:ffff
195fc6c:2000::/20fc6c:2fff:ffff:ffff:ffff:ffff:ffff:ffff
196fc6c:3000::/20fc6c:3fff:ffff:ffff:ffff:ffff:ffff:ffff
197fc6c:4000::/20fc6c:4fff:ffff:ffff:ffff:ffff:ffff:ffff
198fc6c:5000::/20fc6c:5fff:ffff:ffff:ffff:ffff:ffff:ffff
199fc6c:6000::/20fc6c:6fff:ffff:ffff:ffff:ffff:ffff:ffff
200fc6c:7000::/20fc6c:7fff:ffff:ffff:ffff:ffff:ffff:ffff
201fc6c:8000::/20fc6c:8fff:ffff:ffff:ffff:ffff:ffff:ffff
202fc6c:9000::/20fc6c:9fff:ffff:ffff:ffff:ffff:ffff:ffff
203fc6c:a000::/20fc6c:afff:ffff:ffff:ffff:ffff:ffff:ffff
204fc6c:b000::/20fc6c:bfff:ffff:ffff:ffff:ffff:ffff:ffff
205fc6c:c000::/20fc6c:cfff:ffff:ffff:ffff:ffff:ffff:ffff
206fc6c:d000::/20fc6c:dfff:ffff:ffff:ffff:ffff:ffff:ffff
207fc6c:e000::/20fc6c:efff:ffff:ffff:ffff:ffff:ffff:ffff
208fc6c:f000::/20fc6c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
209fc6d::/20fc6d:fff:ffff:ffff:ffff:ffff:ffff:ffff
210fc6d:1000::/20fc6d:1fff:ffff:ffff:ffff:ffff:ffff:ffff
211fc6d:2000::/20fc6d:2fff:ffff:ffff:ffff:ffff:ffff:ffff
212fc6d:3000::/20fc6d:3fff:ffff:ffff:ffff:ffff:ffff:ffff
213fc6d:4000::/20fc6d:4fff:ffff:ffff:ffff:ffff:ffff:ffff
214fc6d:5000::/20fc6d:5fff:ffff:ffff:ffff:ffff:ffff:ffff
215fc6d:6000::/20fc6d:6fff:ffff:ffff:ffff:ffff:ffff:ffff
216fc6d:7000::/20fc6d:7fff:ffff:ffff:ffff:ffff:ffff:ffff
217fc6d:8000::/20fc6d:8fff:ffff:ffff:ffff:ffff:ffff:ffff
218fc6d:9000::/20fc6d:9fff:ffff:ffff:ffff:ffff:ffff:ffff
219fc6d:a000::/20fc6d:afff:ffff:ffff:ffff:ffff:ffff:ffff
220fc6d:b000::/20fc6d:bfff:ffff:ffff:ffff:ffff:ffff:ffff
221fc6d:c000::/20fc6d:cfff:ffff:ffff:ffff:ffff:ffff:ffff
222fc6d:d000::/20fc6d:dfff:ffff:ffff:ffff:ffff:ffff:ffff
223fc6d:e000::/20fc6d:efff:ffff:ffff:ffff:ffff:ffff:ffff
224fc6d:f000::/20fc6d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
225fc6e::/20fc6e:fff:ffff:ffff:ffff:ffff:ffff:ffff
226fc6e:1000::/20fc6e:1fff:ffff:ffff:ffff:ffff:ffff:ffff
227fc6e:2000::/20fc6e:2fff:ffff:ffff:ffff:ffff:ffff:ffff
228fc6e:3000::/20fc6e:3fff:ffff:ffff:ffff:ffff:ffff:ffff
229fc6e:4000::/20fc6e:4fff:ffff:ffff:ffff:ffff:ffff:ffff
230fc6e:5000::/20fc6e:5fff:ffff:ffff:ffff:ffff:ffff:ffff
231fc6e:6000::/20fc6e:6fff:ffff:ffff:ffff:ffff:ffff:ffff
232fc6e:7000::/20fc6e:7fff:ffff:ffff:ffff:ffff:ffff:ffff
233fc6e:8000::/20fc6e:8fff:ffff:ffff:ffff:ffff:ffff:ffff
234fc6e:9000::/20fc6e:9fff:ffff:ffff:ffff:ffff:ffff:ffff
235fc6e:a000::/20fc6e:afff:ffff:ffff:ffff:ffff:ffff:ffff
236fc6e:b000::/20fc6e:bfff:ffff:ffff:ffff:ffff:ffff:ffff
237fc6e:c000::/20fc6e:cfff:ffff:ffff:ffff:ffff:ffff:ffff
238fc6e:d000::/20fc6e:dfff:ffff:ffff:ffff:ffff:ffff:ffff
239fc6e:e000::/20fc6e:efff:ffff:ffff:ffff:ffff:ffff:ffff
240fc6e:f000::/20fc6e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
241fc6f::/20fc6f:fff:ffff:ffff:ffff:ffff:ffff:ffff
242fc6f:1000::/20fc6f:1fff:ffff:ffff:ffff:ffff:ffff:ffff
243fc6f:2000::/20fc6f:2fff:ffff:ffff:ffff:ffff:ffff:ffff
244fc6f:3000::/20fc6f:3fff:ffff:ffff:ffff:ffff:ffff:ffff
245fc6f:4000::/20fc6f:4fff:ffff:ffff:ffff:ffff:ffff:ffff
246fc6f:5000::/20fc6f:5fff:ffff:ffff:ffff:ffff:ffff:ffff
247fc6f:6000::/20fc6f:6fff:ffff:ffff:ffff:ffff:ffff:ffff
248fc6f:7000::/20fc6f:7fff:ffff:ffff:ffff:ffff:ffff:ffff
249fc6f:8000::/20fc6f:8fff:ffff:ffff:ffff:ffff:ffff:ffff
250fc6f:9000::/20fc6f:9fff:ffff:ffff:ffff:ffff:ffff:ffff
251fc6f:a000::/20fc6f:afff:ffff:ffff:ffff:ffff:ffff:ffff
252fc6f:b000::/20fc6f:bfff:ffff:ffff:ffff:ffff:ffff:ffff
253fc6f:c000::/20fc6f:cfff:ffff:ffff:ffff:ffff:ffff:ffff
254fc6f:d000::/20fc6f:dfff:ffff:ffff:ffff:ffff:ffff:ffff
255fc6f:e000::/20fc6f:efff:ffff:ffff:ffff:ffff:ffff:ffff
256fc6f:f000::/20fc6f:ffff: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.