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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
fc60::/16
First address
fc60::
Last address
fc60: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
fc60:0000:0000:0000:0000:0000:0000:0000
Type
Unique local (ULA) fc00::/7
Private IPv6, like RFC 1918; usually fd00::/8
Reverse DNS zone
0.6.c.f.ip6.arpa
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

fc60::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
1fc60::/24fc60:ff:ffff:ffff:ffff:ffff:ffff:ffff
2fc60:100::/24fc60:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3fc60:200::/24fc60:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4fc60:300::/24fc60:3ff:ffff:ffff:ffff:ffff:ffff:ffff
5fc60:400::/24fc60:4ff:ffff:ffff:ffff:ffff:ffff:ffff
6fc60:500::/24fc60:5ff:ffff:ffff:ffff:ffff:ffff:ffff
7fc60:600::/24fc60:6ff:ffff:ffff:ffff:ffff:ffff:ffff
8fc60:700::/24fc60:7ff:ffff:ffff:ffff:ffff:ffff:ffff
9fc60:800::/24fc60:8ff:ffff:ffff:ffff:ffff:ffff:ffff
10fc60:900::/24fc60:9ff:ffff:ffff:ffff:ffff:ffff:ffff
11fc60:a00::/24fc60:aff:ffff:ffff:ffff:ffff:ffff:ffff
12fc60:b00::/24fc60:bff:ffff:ffff:ffff:ffff:ffff:ffff
13fc60:c00::/24fc60:cff:ffff:ffff:ffff:ffff:ffff:ffff
14fc60:d00::/24fc60:dff:ffff:ffff:ffff:ffff:ffff:ffff
15fc60:e00::/24fc60:eff:ffff:ffff:ffff:ffff:ffff:ffff
16fc60:f00::/24fc60:fff:ffff:ffff:ffff:ffff:ffff:ffff
17fc60:1000::/24fc60:10ff:ffff:ffff:ffff:ffff:ffff:ffff
18fc60:1100::/24fc60:11ff:ffff:ffff:ffff:ffff:ffff:ffff
19fc60:1200::/24fc60:12ff:ffff:ffff:ffff:ffff:ffff:ffff
20fc60:1300::/24fc60:13ff:ffff:ffff:ffff:ffff:ffff:ffff
21fc60:1400::/24fc60:14ff:ffff:ffff:ffff:ffff:ffff:ffff
22fc60:1500::/24fc60:15ff:ffff:ffff:ffff:ffff:ffff:ffff
23fc60:1600::/24fc60:16ff:ffff:ffff:ffff:ffff:ffff:ffff
24fc60:1700::/24fc60:17ff:ffff:ffff:ffff:ffff:ffff:ffff
25fc60:1800::/24fc60:18ff:ffff:ffff:ffff:ffff:ffff:ffff
26fc60:1900::/24fc60:19ff:ffff:ffff:ffff:ffff:ffff:ffff
27fc60:1a00::/24fc60:1aff:ffff:ffff:ffff:ffff:ffff:ffff
28fc60:1b00::/24fc60:1bff:ffff:ffff:ffff:ffff:ffff:ffff
29fc60:1c00::/24fc60:1cff:ffff:ffff:ffff:ffff:ffff:ffff
30fc60:1d00::/24fc60:1dff:ffff:ffff:ffff:ffff:ffff:ffff
31fc60:1e00::/24fc60:1eff:ffff:ffff:ffff:ffff:ffff:ffff
32fc60:1f00::/24fc60:1fff:ffff:ffff:ffff:ffff:ffff:ffff
33fc60:2000::/24fc60:20ff:ffff:ffff:ffff:ffff:ffff:ffff
34fc60:2100::/24fc60:21ff:ffff:ffff:ffff:ffff:ffff:ffff
35fc60:2200::/24fc60:22ff:ffff:ffff:ffff:ffff:ffff:ffff
36fc60:2300::/24fc60:23ff:ffff:ffff:ffff:ffff:ffff:ffff
37fc60:2400::/24fc60:24ff:ffff:ffff:ffff:ffff:ffff:ffff
38fc60:2500::/24fc60:25ff:ffff:ffff:ffff:ffff:ffff:ffff
39fc60:2600::/24fc60:26ff:ffff:ffff:ffff:ffff:ffff:ffff
40fc60:2700::/24fc60:27ff:ffff:ffff:ffff:ffff:ffff:ffff
41fc60:2800::/24fc60:28ff:ffff:ffff:ffff:ffff:ffff:ffff
42fc60:2900::/24fc60:29ff:ffff:ffff:ffff:ffff:ffff:ffff
43fc60:2a00::/24fc60:2aff:ffff:ffff:ffff:ffff:ffff:ffff
44fc60:2b00::/24fc60:2bff:ffff:ffff:ffff:ffff:ffff:ffff
45fc60:2c00::/24fc60:2cff:ffff:ffff:ffff:ffff:ffff:ffff
46fc60:2d00::/24fc60:2dff:ffff:ffff:ffff:ffff:ffff:ffff
47fc60:2e00::/24fc60:2eff:ffff:ffff:ffff:ffff:ffff:ffff
48fc60:2f00::/24fc60:2fff:ffff:ffff:ffff:ffff:ffff:ffff
49fc60:3000::/24fc60:30ff:ffff:ffff:ffff:ffff:ffff:ffff
50fc60:3100::/24fc60:31ff:ffff:ffff:ffff:ffff:ffff:ffff
51fc60:3200::/24fc60:32ff:ffff:ffff:ffff:ffff:ffff:ffff
52fc60:3300::/24fc60:33ff:ffff:ffff:ffff:ffff:ffff:ffff
53fc60:3400::/24fc60:34ff:ffff:ffff:ffff:ffff:ffff:ffff
54fc60:3500::/24fc60:35ff:ffff:ffff:ffff:ffff:ffff:ffff
55fc60:3600::/24fc60:36ff:ffff:ffff:ffff:ffff:ffff:ffff
56fc60:3700::/24fc60:37ff:ffff:ffff:ffff:ffff:ffff:ffff
57fc60:3800::/24fc60:38ff:ffff:ffff:ffff:ffff:ffff:ffff
58fc60:3900::/24fc60:39ff:ffff:ffff:ffff:ffff:ffff:ffff
59fc60:3a00::/24fc60:3aff:ffff:ffff:ffff:ffff:ffff:ffff
60fc60:3b00::/24fc60:3bff:ffff:ffff:ffff:ffff:ffff:ffff
61fc60:3c00::/24fc60:3cff:ffff:ffff:ffff:ffff:ffff:ffff
62fc60:3d00::/24fc60:3dff:ffff:ffff:ffff:ffff:ffff:ffff
63fc60:3e00::/24fc60:3eff:ffff:ffff:ffff:ffff:ffff:ffff
64fc60:3f00::/24fc60:3fff:ffff:ffff:ffff:ffff:ffff:ffff
65fc60:4000::/24fc60:40ff:ffff:ffff:ffff:ffff:ffff:ffff
66fc60:4100::/24fc60:41ff:ffff:ffff:ffff:ffff:ffff:ffff
67fc60:4200::/24fc60:42ff:ffff:ffff:ffff:ffff:ffff:ffff
68fc60:4300::/24fc60:43ff:ffff:ffff:ffff:ffff:ffff:ffff
69fc60:4400::/24fc60:44ff:ffff:ffff:ffff:ffff:ffff:ffff
70fc60:4500::/24fc60:45ff:ffff:ffff:ffff:ffff:ffff:ffff
71fc60:4600::/24fc60:46ff:ffff:ffff:ffff:ffff:ffff:ffff
72fc60:4700::/24fc60:47ff:ffff:ffff:ffff:ffff:ffff:ffff
73fc60:4800::/24fc60:48ff:ffff:ffff:ffff:ffff:ffff:ffff
74fc60:4900::/24fc60:49ff:ffff:ffff:ffff:ffff:ffff:ffff
75fc60:4a00::/24fc60:4aff:ffff:ffff:ffff:ffff:ffff:ffff
76fc60:4b00::/24fc60:4bff:ffff:ffff:ffff:ffff:ffff:ffff
77fc60:4c00::/24fc60:4cff:ffff:ffff:ffff:ffff:ffff:ffff
78fc60:4d00::/24fc60:4dff:ffff:ffff:ffff:ffff:ffff:ffff
79fc60:4e00::/24fc60:4eff:ffff:ffff:ffff:ffff:ffff:ffff
80fc60:4f00::/24fc60:4fff:ffff:ffff:ffff:ffff:ffff:ffff
81fc60:5000::/24fc60:50ff:ffff:ffff:ffff:ffff:ffff:ffff
82fc60:5100::/24fc60:51ff:ffff:ffff:ffff:ffff:ffff:ffff
83fc60:5200::/24fc60:52ff:ffff:ffff:ffff:ffff:ffff:ffff
84fc60:5300::/24fc60:53ff:ffff:ffff:ffff:ffff:ffff:ffff
85fc60:5400::/24fc60:54ff:ffff:ffff:ffff:ffff:ffff:ffff
86fc60:5500::/24fc60:55ff:ffff:ffff:ffff:ffff:ffff:ffff
87fc60:5600::/24fc60:56ff:ffff:ffff:ffff:ffff:ffff:ffff
88fc60:5700::/24fc60:57ff:ffff:ffff:ffff:ffff:ffff:ffff
89fc60:5800::/24fc60:58ff:ffff:ffff:ffff:ffff:ffff:ffff
90fc60:5900::/24fc60:59ff:ffff:ffff:ffff:ffff:ffff:ffff
91fc60:5a00::/24fc60:5aff:ffff:ffff:ffff:ffff:ffff:ffff
92fc60:5b00::/24fc60:5bff:ffff:ffff:ffff:ffff:ffff:ffff
93fc60:5c00::/24fc60:5cff:ffff:ffff:ffff:ffff:ffff:ffff
94fc60:5d00::/24fc60:5dff:ffff:ffff:ffff:ffff:ffff:ffff
95fc60:5e00::/24fc60:5eff:ffff:ffff:ffff:ffff:ffff:ffff
96fc60:5f00::/24fc60:5fff:ffff:ffff:ffff:ffff:ffff:ffff
97fc60:6000::/24fc60:60ff:ffff:ffff:ffff:ffff:ffff:ffff
98fc60:6100::/24fc60:61ff:ffff:ffff:ffff:ffff:ffff:ffff
99fc60:6200::/24fc60:62ff:ffff:ffff:ffff:ffff:ffff:ffff
100fc60:6300::/24fc60:63ff:ffff:ffff:ffff:ffff:ffff:ffff
101fc60:6400::/24fc60:64ff:ffff:ffff:ffff:ffff:ffff:ffff
102fc60:6500::/24fc60:65ff:ffff:ffff:ffff:ffff:ffff:ffff
103fc60:6600::/24fc60:66ff:ffff:ffff:ffff:ffff:ffff:ffff
104fc60:6700::/24fc60:67ff:ffff:ffff:ffff:ffff:ffff:ffff
105fc60:6800::/24fc60:68ff:ffff:ffff:ffff:ffff:ffff:ffff
106fc60:6900::/24fc60:69ff:ffff:ffff:ffff:ffff:ffff:ffff
107fc60:6a00::/24fc60:6aff:ffff:ffff:ffff:ffff:ffff:ffff
108fc60:6b00::/24fc60:6bff:ffff:ffff:ffff:ffff:ffff:ffff
109fc60:6c00::/24fc60:6cff:ffff:ffff:ffff:ffff:ffff:ffff
110fc60:6d00::/24fc60:6dff:ffff:ffff:ffff:ffff:ffff:ffff
111fc60:6e00::/24fc60:6eff:ffff:ffff:ffff:ffff:ffff:ffff
112fc60:6f00::/24fc60:6fff:ffff:ffff:ffff:ffff:ffff:ffff
113fc60:7000::/24fc60:70ff:ffff:ffff:ffff:ffff:ffff:ffff
114fc60:7100::/24fc60:71ff:ffff:ffff:ffff:ffff:ffff:ffff
115fc60:7200::/24fc60:72ff:ffff:ffff:ffff:ffff:ffff:ffff
116fc60:7300::/24fc60:73ff:ffff:ffff:ffff:ffff:ffff:ffff
117fc60:7400::/24fc60:74ff:ffff:ffff:ffff:ffff:ffff:ffff
118fc60:7500::/24fc60:75ff:ffff:ffff:ffff:ffff:ffff:ffff
119fc60:7600::/24fc60:76ff:ffff:ffff:ffff:ffff:ffff:ffff
120fc60:7700::/24fc60:77ff:ffff:ffff:ffff:ffff:ffff:ffff
121fc60:7800::/24fc60:78ff:ffff:ffff:ffff:ffff:ffff:ffff
122fc60:7900::/24fc60:79ff:ffff:ffff:ffff:ffff:ffff:ffff
123fc60:7a00::/24fc60:7aff:ffff:ffff:ffff:ffff:ffff:ffff
124fc60:7b00::/24fc60:7bff:ffff:ffff:ffff:ffff:ffff:ffff
125fc60:7c00::/24fc60:7cff:ffff:ffff:ffff:ffff:ffff:ffff
126fc60:7d00::/24fc60:7dff:ffff:ffff:ffff:ffff:ffff:ffff
127fc60:7e00::/24fc60:7eff:ffff:ffff:ffff:ffff:ffff:ffff
128fc60:7f00::/24fc60:7fff:ffff:ffff:ffff:ffff:ffff:ffff
129fc60:8000::/24fc60:80ff:ffff:ffff:ffff:ffff:ffff:ffff
130fc60:8100::/24fc60:81ff:ffff:ffff:ffff:ffff:ffff:ffff
131fc60:8200::/24fc60:82ff:ffff:ffff:ffff:ffff:ffff:ffff
132fc60:8300::/24fc60:83ff:ffff:ffff:ffff:ffff:ffff:ffff
133fc60:8400::/24fc60:84ff:ffff:ffff:ffff:ffff:ffff:ffff
134fc60:8500::/24fc60:85ff:ffff:ffff:ffff:ffff:ffff:ffff
135fc60:8600::/24fc60:86ff:ffff:ffff:ffff:ffff:ffff:ffff
136fc60:8700::/24fc60:87ff:ffff:ffff:ffff:ffff:ffff:ffff
137fc60:8800::/24fc60:88ff:ffff:ffff:ffff:ffff:ffff:ffff
138fc60:8900::/24fc60:89ff:ffff:ffff:ffff:ffff:ffff:ffff
139fc60:8a00::/24fc60:8aff:ffff:ffff:ffff:ffff:ffff:ffff
140fc60:8b00::/24fc60:8bff:ffff:ffff:ffff:ffff:ffff:ffff
141fc60:8c00::/24fc60:8cff:ffff:ffff:ffff:ffff:ffff:ffff
142fc60:8d00::/24fc60:8dff:ffff:ffff:ffff:ffff:ffff:ffff
143fc60:8e00::/24fc60:8eff:ffff:ffff:ffff:ffff:ffff:ffff
144fc60:8f00::/24fc60:8fff:ffff:ffff:ffff:ffff:ffff:ffff
145fc60:9000::/24fc60:90ff:ffff:ffff:ffff:ffff:ffff:ffff
146fc60:9100::/24fc60:91ff:ffff:ffff:ffff:ffff:ffff:ffff
147fc60:9200::/24fc60:92ff:ffff:ffff:ffff:ffff:ffff:ffff
148fc60:9300::/24fc60:93ff:ffff:ffff:ffff:ffff:ffff:ffff
149fc60:9400::/24fc60:94ff:ffff:ffff:ffff:ffff:ffff:ffff
150fc60:9500::/24fc60:95ff:ffff:ffff:ffff:ffff:ffff:ffff
151fc60:9600::/24fc60:96ff:ffff:ffff:ffff:ffff:ffff:ffff
152fc60:9700::/24fc60:97ff:ffff:ffff:ffff:ffff:ffff:ffff
153fc60:9800::/24fc60:98ff:ffff:ffff:ffff:ffff:ffff:ffff
154fc60:9900::/24fc60:99ff:ffff:ffff:ffff:ffff:ffff:ffff
155fc60:9a00::/24fc60:9aff:ffff:ffff:ffff:ffff:ffff:ffff
156fc60:9b00::/24fc60:9bff:ffff:ffff:ffff:ffff:ffff:ffff
157fc60:9c00::/24fc60:9cff:ffff:ffff:ffff:ffff:ffff:ffff
158fc60:9d00::/24fc60:9dff:ffff:ffff:ffff:ffff:ffff:ffff
159fc60:9e00::/24fc60:9eff:ffff:ffff:ffff:ffff:ffff:ffff
160fc60:9f00::/24fc60:9fff:ffff:ffff:ffff:ffff:ffff:ffff
161fc60:a000::/24fc60:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
162fc60:a100::/24fc60:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
163fc60:a200::/24fc60:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
164fc60:a300::/24fc60:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
165fc60:a400::/24fc60:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
166fc60:a500::/24fc60:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
167fc60:a600::/24fc60:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
168fc60:a700::/24fc60:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
169fc60:a800::/24fc60:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
170fc60:a900::/24fc60:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
171fc60:aa00::/24fc60:aaff:ffff:ffff:ffff:ffff:ffff:ffff
172fc60:ab00::/24fc60:abff:ffff:ffff:ffff:ffff:ffff:ffff
173fc60:ac00::/24fc60:acff:ffff:ffff:ffff:ffff:ffff:ffff
174fc60:ad00::/24fc60:adff:ffff:ffff:ffff:ffff:ffff:ffff
175fc60:ae00::/24fc60:aeff:ffff:ffff:ffff:ffff:ffff:ffff
176fc60:af00::/24fc60:afff:ffff:ffff:ffff:ffff:ffff:ffff
177fc60:b000::/24fc60:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
178fc60:b100::/24fc60:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
179fc60:b200::/24fc60:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
180fc60:b300::/24fc60:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
181fc60:b400::/24fc60:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
182fc60:b500::/24fc60:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
183fc60:b600::/24fc60:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
184fc60:b700::/24fc60:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
185fc60:b800::/24fc60:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
186fc60:b900::/24fc60:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
187fc60:ba00::/24fc60:baff:ffff:ffff:ffff:ffff:ffff:ffff
188fc60:bb00::/24fc60:bbff:ffff:ffff:ffff:ffff:ffff:ffff
189fc60:bc00::/24fc60:bcff:ffff:ffff:ffff:ffff:ffff:ffff
190fc60:bd00::/24fc60:bdff:ffff:ffff:ffff:ffff:ffff:ffff
191fc60:be00::/24fc60:beff:ffff:ffff:ffff:ffff:ffff:ffff
192fc60:bf00::/24fc60:bfff:ffff:ffff:ffff:ffff:ffff:ffff
193fc60:c000::/24fc60:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
194fc60:c100::/24fc60:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
195fc60:c200::/24fc60:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
196fc60:c300::/24fc60:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
197fc60:c400::/24fc60:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
198fc60:c500::/24fc60:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
199fc60:c600::/24fc60:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
200fc60:c700::/24fc60:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
201fc60:c800::/24fc60:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
202fc60:c900::/24fc60:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
203fc60:ca00::/24fc60:caff:ffff:ffff:ffff:ffff:ffff:ffff
204fc60:cb00::/24fc60:cbff:ffff:ffff:ffff:ffff:ffff:ffff
205fc60:cc00::/24fc60:ccff:ffff:ffff:ffff:ffff:ffff:ffff
206fc60:cd00::/24fc60:cdff:ffff:ffff:ffff:ffff:ffff:ffff
207fc60:ce00::/24fc60:ceff:ffff:ffff:ffff:ffff:ffff:ffff
208fc60:cf00::/24fc60:cfff:ffff:ffff:ffff:ffff:ffff:ffff
209fc60:d000::/24fc60:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
210fc60:d100::/24fc60:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
211fc60:d200::/24fc60:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
212fc60:d300::/24fc60:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
213fc60:d400::/24fc60:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
214fc60:d500::/24fc60:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
215fc60:d600::/24fc60:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
216fc60:d700::/24fc60:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
217fc60:d800::/24fc60:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
218fc60:d900::/24fc60:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
219fc60:da00::/24fc60:daff:ffff:ffff:ffff:ffff:ffff:ffff
220fc60:db00::/24fc60:dbff:ffff:ffff:ffff:ffff:ffff:ffff
221fc60:dc00::/24fc60:dcff:ffff:ffff:ffff:ffff:ffff:ffff
222fc60:dd00::/24fc60:ddff:ffff:ffff:ffff:ffff:ffff:ffff
223fc60:de00::/24fc60:deff:ffff:ffff:ffff:ffff:ffff:ffff
224fc60:df00::/24fc60:dfff:ffff:ffff:ffff:ffff:ffff:ffff
225fc60:e000::/24fc60:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
226fc60:e100::/24fc60:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
227fc60:e200::/24fc60:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
228fc60:e300::/24fc60:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
229fc60:e400::/24fc60:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
230fc60:e500::/24fc60:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
231fc60:e600::/24fc60:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
232fc60:e700::/24fc60:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
233fc60:e800::/24fc60:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
234fc60:e900::/24fc60:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
235fc60:ea00::/24fc60:eaff:ffff:ffff:ffff:ffff:ffff:ffff
236fc60:eb00::/24fc60:ebff:ffff:ffff:ffff:ffff:ffff:ffff
237fc60:ec00::/24fc60:ecff:ffff:ffff:ffff:ffff:ffff:ffff
238fc60:ed00::/24fc60:edff:ffff:ffff:ffff:ffff:ffff:ffff
239fc60:ee00::/24fc60:eeff:ffff:ffff:ffff:ffff:ffff:ffff
240fc60:ef00::/24fc60:efff:ffff:ffff:ffff:ffff:ffff:ffff
241fc60:f000::/24fc60:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
242fc60:f100::/24fc60:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
243fc60:f200::/24fc60:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
244fc60:f300::/24fc60:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
245fc60:f400::/24fc60:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
246fc60:f500::/24fc60:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
247fc60:f600::/24fc60:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
248fc60:f700::/24fc60:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
249fc60:f800::/24fc60:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
250fc60:f900::/24fc60:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
251fc60:fa00::/24fc60:faff:ffff:ffff:ffff:ffff:ffff:ffff
252fc60:fb00::/24fc60:fbff:ffff:ffff:ffff:ffff:ffff:ffff
253fc60:fc00::/24fc60:fcff:ffff:ffff:ffff:ffff:ffff:ffff
254fc60:fd00::/24fc60:fdff:ffff:ffff:ffff:ffff:ffff:ffff
255fc60:fe00::/24fc60:feff:ffff:ffff:ffff:ffff:ffff:ffff
256fc60:ff00::/24fc60: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.