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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/16
Addresses2^112
/64 networks2^48
Network
fc96::/16
First address
fc96::
Last address
fc96:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
5,192,296,858,534,827,628,530,496,329,220,096 (2^112)
/64 networks (LANs)
281,474,976,710,656 (2^48)
Full form
fc96:0000:0000:0000:0000:0000:0000:0000
Type
Unique local (ULA) fc00::/7
Private IPv6, like RFC 1918; usually fd00::/8
Reverse DNS zone
6.9.c.f.ip6.arpa
Split into smaller subnets/32
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

fc96::/16 makes 65,536 subnets of /32; the first 256 are listed.

Subnets
#SubnetLast address
1fc96::/32fc96:0:ffff:ffff:ffff:ffff:ffff:ffff
2fc96:1::/32fc96:1:ffff:ffff:ffff:ffff:ffff:ffff
3fc96:2::/32fc96:2:ffff:ffff:ffff:ffff:ffff:ffff
4fc96:3::/32fc96:3:ffff:ffff:ffff:ffff:ffff:ffff
5fc96:4::/32fc96:4:ffff:ffff:ffff:ffff:ffff:ffff
6fc96:5::/32fc96:5:ffff:ffff:ffff:ffff:ffff:ffff
7fc96:6::/32fc96:6:ffff:ffff:ffff:ffff:ffff:ffff
8fc96:7::/32fc96:7:ffff:ffff:ffff:ffff:ffff:ffff
9fc96:8::/32fc96:8:ffff:ffff:ffff:ffff:ffff:ffff
10fc96:9::/32fc96:9:ffff:ffff:ffff:ffff:ffff:ffff
11fc96:a::/32fc96:a:ffff:ffff:ffff:ffff:ffff:ffff
12fc96:b::/32fc96:b:ffff:ffff:ffff:ffff:ffff:ffff
13fc96:c::/32fc96:c:ffff:ffff:ffff:ffff:ffff:ffff
14fc96:d::/32fc96:d:ffff:ffff:ffff:ffff:ffff:ffff
15fc96:e::/32fc96:e:ffff:ffff:ffff:ffff:ffff:ffff
16fc96:f::/32fc96:f:ffff:ffff:ffff:ffff:ffff:ffff
17fc96:10::/32fc96:10:ffff:ffff:ffff:ffff:ffff:ffff
18fc96:11::/32fc96:11:ffff:ffff:ffff:ffff:ffff:ffff
19fc96:12::/32fc96:12:ffff:ffff:ffff:ffff:ffff:ffff
20fc96:13::/32fc96:13:ffff:ffff:ffff:ffff:ffff:ffff
21fc96:14::/32fc96:14:ffff:ffff:ffff:ffff:ffff:ffff
22fc96:15::/32fc96:15:ffff:ffff:ffff:ffff:ffff:ffff
23fc96:16::/32fc96:16:ffff:ffff:ffff:ffff:ffff:ffff
24fc96:17::/32fc96:17:ffff:ffff:ffff:ffff:ffff:ffff
25fc96:18::/32fc96:18:ffff:ffff:ffff:ffff:ffff:ffff
26fc96:19::/32fc96:19:ffff:ffff:ffff:ffff:ffff:ffff
27fc96:1a::/32fc96:1a:ffff:ffff:ffff:ffff:ffff:ffff
28fc96:1b::/32fc96:1b:ffff:ffff:ffff:ffff:ffff:ffff
29fc96:1c::/32fc96:1c:ffff:ffff:ffff:ffff:ffff:ffff
30fc96:1d::/32fc96:1d:ffff:ffff:ffff:ffff:ffff:ffff
31fc96:1e::/32fc96:1e:ffff:ffff:ffff:ffff:ffff:ffff
32fc96:1f::/32fc96:1f:ffff:ffff:ffff:ffff:ffff:ffff
33fc96:20::/32fc96:20:ffff:ffff:ffff:ffff:ffff:ffff
34fc96:21::/32fc96:21:ffff:ffff:ffff:ffff:ffff:ffff
35fc96:22::/32fc96:22:ffff:ffff:ffff:ffff:ffff:ffff
36fc96:23::/32fc96:23:ffff:ffff:ffff:ffff:ffff:ffff
37fc96:24::/32fc96:24:ffff:ffff:ffff:ffff:ffff:ffff
38fc96:25::/32fc96:25:ffff:ffff:ffff:ffff:ffff:ffff
39fc96:26::/32fc96:26:ffff:ffff:ffff:ffff:ffff:ffff
40fc96:27::/32fc96:27:ffff:ffff:ffff:ffff:ffff:ffff
41fc96:28::/32fc96:28:ffff:ffff:ffff:ffff:ffff:ffff
42fc96:29::/32fc96:29:ffff:ffff:ffff:ffff:ffff:ffff
43fc96:2a::/32fc96:2a:ffff:ffff:ffff:ffff:ffff:ffff
44fc96:2b::/32fc96:2b:ffff:ffff:ffff:ffff:ffff:ffff
45fc96:2c::/32fc96:2c:ffff:ffff:ffff:ffff:ffff:ffff
46fc96:2d::/32fc96:2d:ffff:ffff:ffff:ffff:ffff:ffff
47fc96:2e::/32fc96:2e:ffff:ffff:ffff:ffff:ffff:ffff
48fc96:2f::/32fc96:2f:ffff:ffff:ffff:ffff:ffff:ffff
49fc96:30::/32fc96:30:ffff:ffff:ffff:ffff:ffff:ffff
50fc96:31::/32fc96:31:ffff:ffff:ffff:ffff:ffff:ffff
51fc96:32::/32fc96:32:ffff:ffff:ffff:ffff:ffff:ffff
52fc96:33::/32fc96:33:ffff:ffff:ffff:ffff:ffff:ffff
53fc96:34::/32fc96:34:ffff:ffff:ffff:ffff:ffff:ffff
54fc96:35::/32fc96:35:ffff:ffff:ffff:ffff:ffff:ffff
55fc96:36::/32fc96:36:ffff:ffff:ffff:ffff:ffff:ffff
56fc96:37::/32fc96:37:ffff:ffff:ffff:ffff:ffff:ffff
57fc96:38::/32fc96:38:ffff:ffff:ffff:ffff:ffff:ffff
58fc96:39::/32fc96:39:ffff:ffff:ffff:ffff:ffff:ffff
59fc96:3a::/32fc96:3a:ffff:ffff:ffff:ffff:ffff:ffff
60fc96:3b::/32fc96:3b:ffff:ffff:ffff:ffff:ffff:ffff
61fc96:3c::/32fc96:3c:ffff:ffff:ffff:ffff:ffff:ffff
62fc96:3d::/32fc96:3d:ffff:ffff:ffff:ffff:ffff:ffff
63fc96:3e::/32fc96:3e:ffff:ffff:ffff:ffff:ffff:ffff
64fc96:3f::/32fc96:3f:ffff:ffff:ffff:ffff:ffff:ffff
65fc96:40::/32fc96:40:ffff:ffff:ffff:ffff:ffff:ffff
66fc96:41::/32fc96:41:ffff:ffff:ffff:ffff:ffff:ffff
67fc96:42::/32fc96:42:ffff:ffff:ffff:ffff:ffff:ffff
68fc96:43::/32fc96:43:ffff:ffff:ffff:ffff:ffff:ffff
69fc96:44::/32fc96:44:ffff:ffff:ffff:ffff:ffff:ffff
70fc96:45::/32fc96:45:ffff:ffff:ffff:ffff:ffff:ffff
71fc96:46::/32fc96:46:ffff:ffff:ffff:ffff:ffff:ffff
72fc96:47::/32fc96:47:ffff:ffff:ffff:ffff:ffff:ffff
73fc96:48::/32fc96:48:ffff:ffff:ffff:ffff:ffff:ffff
74fc96:49::/32fc96:49:ffff:ffff:ffff:ffff:ffff:ffff
75fc96:4a::/32fc96:4a:ffff:ffff:ffff:ffff:ffff:ffff
76fc96:4b::/32fc96:4b:ffff:ffff:ffff:ffff:ffff:ffff
77fc96:4c::/32fc96:4c:ffff:ffff:ffff:ffff:ffff:ffff
78fc96:4d::/32fc96:4d:ffff:ffff:ffff:ffff:ffff:ffff
79fc96:4e::/32fc96:4e:ffff:ffff:ffff:ffff:ffff:ffff
80fc96:4f::/32fc96:4f:ffff:ffff:ffff:ffff:ffff:ffff
81fc96:50::/32fc96:50:ffff:ffff:ffff:ffff:ffff:ffff
82fc96:51::/32fc96:51:ffff:ffff:ffff:ffff:ffff:ffff
83fc96:52::/32fc96:52:ffff:ffff:ffff:ffff:ffff:ffff
84fc96:53::/32fc96:53:ffff:ffff:ffff:ffff:ffff:ffff
85fc96:54::/32fc96:54:ffff:ffff:ffff:ffff:ffff:ffff
86fc96:55::/32fc96:55:ffff:ffff:ffff:ffff:ffff:ffff
87fc96:56::/32fc96:56:ffff:ffff:ffff:ffff:ffff:ffff
88fc96:57::/32fc96:57:ffff:ffff:ffff:ffff:ffff:ffff
89fc96:58::/32fc96:58:ffff:ffff:ffff:ffff:ffff:ffff
90fc96:59::/32fc96:59:ffff:ffff:ffff:ffff:ffff:ffff
91fc96:5a::/32fc96:5a:ffff:ffff:ffff:ffff:ffff:ffff
92fc96:5b::/32fc96:5b:ffff:ffff:ffff:ffff:ffff:ffff
93fc96:5c::/32fc96:5c:ffff:ffff:ffff:ffff:ffff:ffff
94fc96:5d::/32fc96:5d:ffff:ffff:ffff:ffff:ffff:ffff
95fc96:5e::/32fc96:5e:ffff:ffff:ffff:ffff:ffff:ffff
96fc96:5f::/32fc96:5f:ffff:ffff:ffff:ffff:ffff:ffff
97fc96:60::/32fc96:60:ffff:ffff:ffff:ffff:ffff:ffff
98fc96:61::/32fc96:61:ffff:ffff:ffff:ffff:ffff:ffff
99fc96:62::/32fc96:62:ffff:ffff:ffff:ffff:ffff:ffff
100fc96:63::/32fc96:63:ffff:ffff:ffff:ffff:ffff:ffff
101fc96:64::/32fc96:64:ffff:ffff:ffff:ffff:ffff:ffff
102fc96:65::/32fc96:65:ffff:ffff:ffff:ffff:ffff:ffff
103fc96:66::/32fc96:66:ffff:ffff:ffff:ffff:ffff:ffff
104fc96:67::/32fc96:67:ffff:ffff:ffff:ffff:ffff:ffff
105fc96:68::/32fc96:68:ffff:ffff:ffff:ffff:ffff:ffff
106fc96:69::/32fc96:69:ffff:ffff:ffff:ffff:ffff:ffff
107fc96:6a::/32fc96:6a:ffff:ffff:ffff:ffff:ffff:ffff
108fc96:6b::/32fc96:6b:ffff:ffff:ffff:ffff:ffff:ffff
109fc96:6c::/32fc96:6c:ffff:ffff:ffff:ffff:ffff:ffff
110fc96:6d::/32fc96:6d:ffff:ffff:ffff:ffff:ffff:ffff
111fc96:6e::/32fc96:6e:ffff:ffff:ffff:ffff:ffff:ffff
112fc96:6f::/32fc96:6f:ffff:ffff:ffff:ffff:ffff:ffff
113fc96:70::/32fc96:70:ffff:ffff:ffff:ffff:ffff:ffff
114fc96:71::/32fc96:71:ffff:ffff:ffff:ffff:ffff:ffff
115fc96:72::/32fc96:72:ffff:ffff:ffff:ffff:ffff:ffff
116fc96:73::/32fc96:73:ffff:ffff:ffff:ffff:ffff:ffff
117fc96:74::/32fc96:74:ffff:ffff:ffff:ffff:ffff:ffff
118fc96:75::/32fc96:75:ffff:ffff:ffff:ffff:ffff:ffff
119fc96:76::/32fc96:76:ffff:ffff:ffff:ffff:ffff:ffff
120fc96:77::/32fc96:77:ffff:ffff:ffff:ffff:ffff:ffff
121fc96:78::/32fc96:78:ffff:ffff:ffff:ffff:ffff:ffff
122fc96:79::/32fc96:79:ffff:ffff:ffff:ffff:ffff:ffff
123fc96:7a::/32fc96:7a:ffff:ffff:ffff:ffff:ffff:ffff
124fc96:7b::/32fc96:7b:ffff:ffff:ffff:ffff:ffff:ffff
125fc96:7c::/32fc96:7c:ffff:ffff:ffff:ffff:ffff:ffff
126fc96:7d::/32fc96:7d:ffff:ffff:ffff:ffff:ffff:ffff
127fc96:7e::/32fc96:7e:ffff:ffff:ffff:ffff:ffff:ffff
128fc96:7f::/32fc96:7f:ffff:ffff:ffff:ffff:ffff:ffff
129fc96:80::/32fc96:80:ffff:ffff:ffff:ffff:ffff:ffff
130fc96:81::/32fc96:81:ffff:ffff:ffff:ffff:ffff:ffff
131fc96:82::/32fc96:82:ffff:ffff:ffff:ffff:ffff:ffff
132fc96:83::/32fc96:83:ffff:ffff:ffff:ffff:ffff:ffff
133fc96:84::/32fc96:84:ffff:ffff:ffff:ffff:ffff:ffff
134fc96:85::/32fc96:85:ffff:ffff:ffff:ffff:ffff:ffff
135fc96:86::/32fc96:86:ffff:ffff:ffff:ffff:ffff:ffff
136fc96:87::/32fc96:87:ffff:ffff:ffff:ffff:ffff:ffff
137fc96:88::/32fc96:88:ffff:ffff:ffff:ffff:ffff:ffff
138fc96:89::/32fc96:89:ffff:ffff:ffff:ffff:ffff:ffff
139fc96:8a::/32fc96:8a:ffff:ffff:ffff:ffff:ffff:ffff
140fc96:8b::/32fc96:8b:ffff:ffff:ffff:ffff:ffff:ffff
141fc96:8c::/32fc96:8c:ffff:ffff:ffff:ffff:ffff:ffff
142fc96:8d::/32fc96:8d:ffff:ffff:ffff:ffff:ffff:ffff
143fc96:8e::/32fc96:8e:ffff:ffff:ffff:ffff:ffff:ffff
144fc96:8f::/32fc96:8f:ffff:ffff:ffff:ffff:ffff:ffff
145fc96:90::/32fc96:90:ffff:ffff:ffff:ffff:ffff:ffff
146fc96:91::/32fc96:91:ffff:ffff:ffff:ffff:ffff:ffff
147fc96:92::/32fc96:92:ffff:ffff:ffff:ffff:ffff:ffff
148fc96:93::/32fc96:93:ffff:ffff:ffff:ffff:ffff:ffff
149fc96:94::/32fc96:94:ffff:ffff:ffff:ffff:ffff:ffff
150fc96:95::/32fc96:95:ffff:ffff:ffff:ffff:ffff:ffff
151fc96:96::/32fc96:96:ffff:ffff:ffff:ffff:ffff:ffff
152fc96:97::/32fc96:97:ffff:ffff:ffff:ffff:ffff:ffff
153fc96:98::/32fc96:98:ffff:ffff:ffff:ffff:ffff:ffff
154fc96:99::/32fc96:99:ffff:ffff:ffff:ffff:ffff:ffff
155fc96:9a::/32fc96:9a:ffff:ffff:ffff:ffff:ffff:ffff
156fc96:9b::/32fc96:9b:ffff:ffff:ffff:ffff:ffff:ffff
157fc96:9c::/32fc96:9c:ffff:ffff:ffff:ffff:ffff:ffff
158fc96:9d::/32fc96:9d:ffff:ffff:ffff:ffff:ffff:ffff
159fc96:9e::/32fc96:9e:ffff:ffff:ffff:ffff:ffff:ffff
160fc96:9f::/32fc96:9f:ffff:ffff:ffff:ffff:ffff:ffff
161fc96:a0::/32fc96:a0:ffff:ffff:ffff:ffff:ffff:ffff
162fc96:a1::/32fc96:a1:ffff:ffff:ffff:ffff:ffff:ffff
163fc96:a2::/32fc96:a2:ffff:ffff:ffff:ffff:ffff:ffff
164fc96:a3::/32fc96:a3:ffff:ffff:ffff:ffff:ffff:ffff
165fc96:a4::/32fc96:a4:ffff:ffff:ffff:ffff:ffff:ffff
166fc96:a5::/32fc96:a5:ffff:ffff:ffff:ffff:ffff:ffff
167fc96:a6::/32fc96:a6:ffff:ffff:ffff:ffff:ffff:ffff
168fc96:a7::/32fc96:a7:ffff:ffff:ffff:ffff:ffff:ffff
169fc96:a8::/32fc96:a8:ffff:ffff:ffff:ffff:ffff:ffff
170fc96:a9::/32fc96:a9:ffff:ffff:ffff:ffff:ffff:ffff
171fc96:aa::/32fc96:aa:ffff:ffff:ffff:ffff:ffff:ffff
172fc96:ab::/32fc96:ab:ffff:ffff:ffff:ffff:ffff:ffff
173fc96:ac::/32fc96:ac:ffff:ffff:ffff:ffff:ffff:ffff
174fc96:ad::/32fc96:ad:ffff:ffff:ffff:ffff:ffff:ffff
175fc96:ae::/32fc96:ae:ffff:ffff:ffff:ffff:ffff:ffff
176fc96:af::/32fc96:af:ffff:ffff:ffff:ffff:ffff:ffff
177fc96:b0::/32fc96:b0:ffff:ffff:ffff:ffff:ffff:ffff
178fc96:b1::/32fc96:b1:ffff:ffff:ffff:ffff:ffff:ffff
179fc96:b2::/32fc96:b2:ffff:ffff:ffff:ffff:ffff:ffff
180fc96:b3::/32fc96:b3:ffff:ffff:ffff:ffff:ffff:ffff
181fc96:b4::/32fc96:b4:ffff:ffff:ffff:ffff:ffff:ffff
182fc96:b5::/32fc96:b5:ffff:ffff:ffff:ffff:ffff:ffff
183fc96:b6::/32fc96:b6:ffff:ffff:ffff:ffff:ffff:ffff
184fc96:b7::/32fc96:b7:ffff:ffff:ffff:ffff:ffff:ffff
185fc96:b8::/32fc96:b8:ffff:ffff:ffff:ffff:ffff:ffff
186fc96:b9::/32fc96:b9:ffff:ffff:ffff:ffff:ffff:ffff
187fc96:ba::/32fc96:ba:ffff:ffff:ffff:ffff:ffff:ffff
188fc96:bb::/32fc96:bb:ffff:ffff:ffff:ffff:ffff:ffff
189fc96:bc::/32fc96:bc:ffff:ffff:ffff:ffff:ffff:ffff
190fc96:bd::/32fc96:bd:ffff:ffff:ffff:ffff:ffff:ffff
191fc96:be::/32fc96:be:ffff:ffff:ffff:ffff:ffff:ffff
192fc96:bf::/32fc96:bf:ffff:ffff:ffff:ffff:ffff:ffff
193fc96:c0::/32fc96:c0:ffff:ffff:ffff:ffff:ffff:ffff
194fc96:c1::/32fc96:c1:ffff:ffff:ffff:ffff:ffff:ffff
195fc96:c2::/32fc96:c2:ffff:ffff:ffff:ffff:ffff:ffff
196fc96:c3::/32fc96:c3:ffff:ffff:ffff:ffff:ffff:ffff
197fc96:c4::/32fc96:c4:ffff:ffff:ffff:ffff:ffff:ffff
198fc96:c5::/32fc96:c5:ffff:ffff:ffff:ffff:ffff:ffff
199fc96:c6::/32fc96:c6:ffff:ffff:ffff:ffff:ffff:ffff
200fc96:c7::/32fc96:c7:ffff:ffff:ffff:ffff:ffff:ffff
201fc96:c8::/32fc96:c8:ffff:ffff:ffff:ffff:ffff:ffff
202fc96:c9::/32fc96:c9:ffff:ffff:ffff:ffff:ffff:ffff
203fc96:ca::/32fc96:ca:ffff:ffff:ffff:ffff:ffff:ffff
204fc96:cb::/32fc96:cb:ffff:ffff:ffff:ffff:ffff:ffff
205fc96:cc::/32fc96:cc:ffff:ffff:ffff:ffff:ffff:ffff
206fc96:cd::/32fc96:cd:ffff:ffff:ffff:ffff:ffff:ffff
207fc96:ce::/32fc96:ce:ffff:ffff:ffff:ffff:ffff:ffff
208fc96:cf::/32fc96:cf:ffff:ffff:ffff:ffff:ffff:ffff
209fc96:d0::/32fc96:d0:ffff:ffff:ffff:ffff:ffff:ffff
210fc96:d1::/32fc96:d1:ffff:ffff:ffff:ffff:ffff:ffff
211fc96:d2::/32fc96:d2:ffff:ffff:ffff:ffff:ffff:ffff
212fc96:d3::/32fc96:d3:ffff:ffff:ffff:ffff:ffff:ffff
213fc96:d4::/32fc96:d4:ffff:ffff:ffff:ffff:ffff:ffff
214fc96:d5::/32fc96:d5:ffff:ffff:ffff:ffff:ffff:ffff
215fc96:d6::/32fc96:d6:ffff:ffff:ffff:ffff:ffff:ffff
216fc96:d7::/32fc96:d7:ffff:ffff:ffff:ffff:ffff:ffff
217fc96:d8::/32fc96:d8:ffff:ffff:ffff:ffff:ffff:ffff
218fc96:d9::/32fc96:d9:ffff:ffff:ffff:ffff:ffff:ffff
219fc96:da::/32fc96:da:ffff:ffff:ffff:ffff:ffff:ffff
220fc96:db::/32fc96:db:ffff:ffff:ffff:ffff:ffff:ffff
221fc96:dc::/32fc96:dc:ffff:ffff:ffff:ffff:ffff:ffff
222fc96:dd::/32fc96:dd:ffff:ffff:ffff:ffff:ffff:ffff
223fc96:de::/32fc96:de:ffff:ffff:ffff:ffff:ffff:ffff
224fc96:df::/32fc96:df:ffff:ffff:ffff:ffff:ffff:ffff
225fc96:e0::/32fc96:e0:ffff:ffff:ffff:ffff:ffff:ffff
226fc96:e1::/32fc96:e1:ffff:ffff:ffff:ffff:ffff:ffff
227fc96:e2::/32fc96:e2:ffff:ffff:ffff:ffff:ffff:ffff
228fc96:e3::/32fc96:e3:ffff:ffff:ffff:ffff:ffff:ffff
229fc96:e4::/32fc96:e4:ffff:ffff:ffff:ffff:ffff:ffff
230fc96:e5::/32fc96:e5:ffff:ffff:ffff:ffff:ffff:ffff
231fc96:e6::/32fc96:e6:ffff:ffff:ffff:ffff:ffff:ffff
232fc96:e7::/32fc96:e7:ffff:ffff:ffff:ffff:ffff:ffff
233fc96:e8::/32fc96:e8:ffff:ffff:ffff:ffff:ffff:ffff
234fc96:e9::/32fc96:e9:ffff:ffff:ffff:ffff:ffff:ffff
235fc96:ea::/32fc96:ea:ffff:ffff:ffff:ffff:ffff:ffff
236fc96:eb::/32fc96:eb:ffff:ffff:ffff:ffff:ffff:ffff
237fc96:ec::/32fc96:ec:ffff:ffff:ffff:ffff:ffff:ffff
238fc96:ed::/32fc96:ed:ffff:ffff:ffff:ffff:ffff:ffff
239fc96:ee::/32fc96:ee:ffff:ffff:ffff:ffff:ffff:ffff
240fc96:ef::/32fc96:ef:ffff:ffff:ffff:ffff:ffff:ffff
241fc96:f0::/32fc96:f0:ffff:ffff:ffff:ffff:ffff:ffff
242fc96:f1::/32fc96:f1:ffff:ffff:ffff:ffff:ffff:ffff
243fc96:f2::/32fc96:f2:ffff:ffff:ffff:ffff:ffff:ffff
244fc96:f3::/32fc96:f3:ffff:ffff:ffff:ffff:ffff:ffff
245fc96:f4::/32fc96:f4:ffff:ffff:ffff:ffff:ffff:ffff
246fc96:f5::/32fc96:f5:ffff:ffff:ffff:ffff:ffff:ffff
247fc96:f6::/32fc96:f6:ffff:ffff:ffff:ffff:ffff:ffff
248fc96:f7::/32fc96:f7:ffff:ffff:ffff:ffff:ffff:ffff
249fc96:f8::/32fc96:f8:ffff:ffff:ffff:ffff:ffff:ffff
250fc96:f9::/32fc96:f9:ffff:ffff:ffff:ffff:ffff:ffff
251fc96:fa::/32fc96:fa:ffff:ffff:ffff:ffff:ffff:ffff
252fc96:fb::/32fc96:fb:ffff:ffff:ffff:ffff:ffff:ffff
253fc96:fc::/32fc96:fc:ffff:ffff:ffff:ffff:ffff:ffff
254fc96:fd::/32fc96:fd:ffff:ffff:ffff:ffff:ffff:ffff
255fc96:fe::/32fc96:fe:ffff:ffff:ffff:ffff:ffff:ffff
256fc96:ff::/32fc96:ff: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.