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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
fc59::/16
First address
fc59::
Last address
fc59: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
fc59:0000:0000:0000:0000:0000:0000:0000
Type
Unique local (ULA) fc00::/7
Private IPv6, like RFC 1918; usually fd00::/8
Reverse DNS zone
9.5.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)

fc59::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
1fc59::/24fc59:ff:ffff:ffff:ffff:ffff:ffff:ffff
2fc59:100::/24fc59:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3fc59:200::/24fc59:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4fc59:300::/24fc59:3ff:ffff:ffff:ffff:ffff:ffff:ffff
5fc59:400::/24fc59:4ff:ffff:ffff:ffff:ffff:ffff:ffff
6fc59:500::/24fc59:5ff:ffff:ffff:ffff:ffff:ffff:ffff
7fc59:600::/24fc59:6ff:ffff:ffff:ffff:ffff:ffff:ffff
8fc59:700::/24fc59:7ff:ffff:ffff:ffff:ffff:ffff:ffff
9fc59:800::/24fc59:8ff:ffff:ffff:ffff:ffff:ffff:ffff
10fc59:900::/24fc59:9ff:ffff:ffff:ffff:ffff:ffff:ffff
11fc59:a00::/24fc59:aff:ffff:ffff:ffff:ffff:ffff:ffff
12fc59:b00::/24fc59:bff:ffff:ffff:ffff:ffff:ffff:ffff
13fc59:c00::/24fc59:cff:ffff:ffff:ffff:ffff:ffff:ffff
14fc59:d00::/24fc59:dff:ffff:ffff:ffff:ffff:ffff:ffff
15fc59:e00::/24fc59:eff:ffff:ffff:ffff:ffff:ffff:ffff
16fc59:f00::/24fc59:fff:ffff:ffff:ffff:ffff:ffff:ffff
17fc59:1000::/24fc59:10ff:ffff:ffff:ffff:ffff:ffff:ffff
18fc59:1100::/24fc59:11ff:ffff:ffff:ffff:ffff:ffff:ffff
19fc59:1200::/24fc59:12ff:ffff:ffff:ffff:ffff:ffff:ffff
20fc59:1300::/24fc59:13ff:ffff:ffff:ffff:ffff:ffff:ffff
21fc59:1400::/24fc59:14ff:ffff:ffff:ffff:ffff:ffff:ffff
22fc59:1500::/24fc59:15ff:ffff:ffff:ffff:ffff:ffff:ffff
23fc59:1600::/24fc59:16ff:ffff:ffff:ffff:ffff:ffff:ffff
24fc59:1700::/24fc59:17ff:ffff:ffff:ffff:ffff:ffff:ffff
25fc59:1800::/24fc59:18ff:ffff:ffff:ffff:ffff:ffff:ffff
26fc59:1900::/24fc59:19ff:ffff:ffff:ffff:ffff:ffff:ffff
27fc59:1a00::/24fc59:1aff:ffff:ffff:ffff:ffff:ffff:ffff
28fc59:1b00::/24fc59:1bff:ffff:ffff:ffff:ffff:ffff:ffff
29fc59:1c00::/24fc59:1cff:ffff:ffff:ffff:ffff:ffff:ffff
30fc59:1d00::/24fc59:1dff:ffff:ffff:ffff:ffff:ffff:ffff
31fc59:1e00::/24fc59:1eff:ffff:ffff:ffff:ffff:ffff:ffff
32fc59:1f00::/24fc59:1fff:ffff:ffff:ffff:ffff:ffff:ffff
33fc59:2000::/24fc59:20ff:ffff:ffff:ffff:ffff:ffff:ffff
34fc59:2100::/24fc59:21ff:ffff:ffff:ffff:ffff:ffff:ffff
35fc59:2200::/24fc59:22ff:ffff:ffff:ffff:ffff:ffff:ffff
36fc59:2300::/24fc59:23ff:ffff:ffff:ffff:ffff:ffff:ffff
37fc59:2400::/24fc59:24ff:ffff:ffff:ffff:ffff:ffff:ffff
38fc59:2500::/24fc59:25ff:ffff:ffff:ffff:ffff:ffff:ffff
39fc59:2600::/24fc59:26ff:ffff:ffff:ffff:ffff:ffff:ffff
40fc59:2700::/24fc59:27ff:ffff:ffff:ffff:ffff:ffff:ffff
41fc59:2800::/24fc59:28ff:ffff:ffff:ffff:ffff:ffff:ffff
42fc59:2900::/24fc59:29ff:ffff:ffff:ffff:ffff:ffff:ffff
43fc59:2a00::/24fc59:2aff:ffff:ffff:ffff:ffff:ffff:ffff
44fc59:2b00::/24fc59:2bff:ffff:ffff:ffff:ffff:ffff:ffff
45fc59:2c00::/24fc59:2cff:ffff:ffff:ffff:ffff:ffff:ffff
46fc59:2d00::/24fc59:2dff:ffff:ffff:ffff:ffff:ffff:ffff
47fc59:2e00::/24fc59:2eff:ffff:ffff:ffff:ffff:ffff:ffff
48fc59:2f00::/24fc59:2fff:ffff:ffff:ffff:ffff:ffff:ffff
49fc59:3000::/24fc59:30ff:ffff:ffff:ffff:ffff:ffff:ffff
50fc59:3100::/24fc59:31ff:ffff:ffff:ffff:ffff:ffff:ffff
51fc59:3200::/24fc59:32ff:ffff:ffff:ffff:ffff:ffff:ffff
52fc59:3300::/24fc59:33ff:ffff:ffff:ffff:ffff:ffff:ffff
53fc59:3400::/24fc59:34ff:ffff:ffff:ffff:ffff:ffff:ffff
54fc59:3500::/24fc59:35ff:ffff:ffff:ffff:ffff:ffff:ffff
55fc59:3600::/24fc59:36ff:ffff:ffff:ffff:ffff:ffff:ffff
56fc59:3700::/24fc59:37ff:ffff:ffff:ffff:ffff:ffff:ffff
57fc59:3800::/24fc59:38ff:ffff:ffff:ffff:ffff:ffff:ffff
58fc59:3900::/24fc59:39ff:ffff:ffff:ffff:ffff:ffff:ffff
59fc59:3a00::/24fc59:3aff:ffff:ffff:ffff:ffff:ffff:ffff
60fc59:3b00::/24fc59:3bff:ffff:ffff:ffff:ffff:ffff:ffff
61fc59:3c00::/24fc59:3cff:ffff:ffff:ffff:ffff:ffff:ffff
62fc59:3d00::/24fc59:3dff:ffff:ffff:ffff:ffff:ffff:ffff
63fc59:3e00::/24fc59:3eff:ffff:ffff:ffff:ffff:ffff:ffff
64fc59:3f00::/24fc59:3fff:ffff:ffff:ffff:ffff:ffff:ffff
65fc59:4000::/24fc59:40ff:ffff:ffff:ffff:ffff:ffff:ffff
66fc59:4100::/24fc59:41ff:ffff:ffff:ffff:ffff:ffff:ffff
67fc59:4200::/24fc59:42ff:ffff:ffff:ffff:ffff:ffff:ffff
68fc59:4300::/24fc59:43ff:ffff:ffff:ffff:ffff:ffff:ffff
69fc59:4400::/24fc59:44ff:ffff:ffff:ffff:ffff:ffff:ffff
70fc59:4500::/24fc59:45ff:ffff:ffff:ffff:ffff:ffff:ffff
71fc59:4600::/24fc59:46ff:ffff:ffff:ffff:ffff:ffff:ffff
72fc59:4700::/24fc59:47ff:ffff:ffff:ffff:ffff:ffff:ffff
73fc59:4800::/24fc59:48ff:ffff:ffff:ffff:ffff:ffff:ffff
74fc59:4900::/24fc59:49ff:ffff:ffff:ffff:ffff:ffff:ffff
75fc59:4a00::/24fc59:4aff:ffff:ffff:ffff:ffff:ffff:ffff
76fc59:4b00::/24fc59:4bff:ffff:ffff:ffff:ffff:ffff:ffff
77fc59:4c00::/24fc59:4cff:ffff:ffff:ffff:ffff:ffff:ffff
78fc59:4d00::/24fc59:4dff:ffff:ffff:ffff:ffff:ffff:ffff
79fc59:4e00::/24fc59:4eff:ffff:ffff:ffff:ffff:ffff:ffff
80fc59:4f00::/24fc59:4fff:ffff:ffff:ffff:ffff:ffff:ffff
81fc59:5000::/24fc59:50ff:ffff:ffff:ffff:ffff:ffff:ffff
82fc59:5100::/24fc59:51ff:ffff:ffff:ffff:ffff:ffff:ffff
83fc59:5200::/24fc59:52ff:ffff:ffff:ffff:ffff:ffff:ffff
84fc59:5300::/24fc59:53ff:ffff:ffff:ffff:ffff:ffff:ffff
85fc59:5400::/24fc59:54ff:ffff:ffff:ffff:ffff:ffff:ffff
86fc59:5500::/24fc59:55ff:ffff:ffff:ffff:ffff:ffff:ffff
87fc59:5600::/24fc59:56ff:ffff:ffff:ffff:ffff:ffff:ffff
88fc59:5700::/24fc59:57ff:ffff:ffff:ffff:ffff:ffff:ffff
89fc59:5800::/24fc59:58ff:ffff:ffff:ffff:ffff:ffff:ffff
90fc59:5900::/24fc59:59ff:ffff:ffff:ffff:ffff:ffff:ffff
91fc59:5a00::/24fc59:5aff:ffff:ffff:ffff:ffff:ffff:ffff
92fc59:5b00::/24fc59:5bff:ffff:ffff:ffff:ffff:ffff:ffff
93fc59:5c00::/24fc59:5cff:ffff:ffff:ffff:ffff:ffff:ffff
94fc59:5d00::/24fc59:5dff:ffff:ffff:ffff:ffff:ffff:ffff
95fc59:5e00::/24fc59:5eff:ffff:ffff:ffff:ffff:ffff:ffff
96fc59:5f00::/24fc59:5fff:ffff:ffff:ffff:ffff:ffff:ffff
97fc59:6000::/24fc59:60ff:ffff:ffff:ffff:ffff:ffff:ffff
98fc59:6100::/24fc59:61ff:ffff:ffff:ffff:ffff:ffff:ffff
99fc59:6200::/24fc59:62ff:ffff:ffff:ffff:ffff:ffff:ffff
100fc59:6300::/24fc59:63ff:ffff:ffff:ffff:ffff:ffff:ffff
101fc59:6400::/24fc59:64ff:ffff:ffff:ffff:ffff:ffff:ffff
102fc59:6500::/24fc59:65ff:ffff:ffff:ffff:ffff:ffff:ffff
103fc59:6600::/24fc59:66ff:ffff:ffff:ffff:ffff:ffff:ffff
104fc59:6700::/24fc59:67ff:ffff:ffff:ffff:ffff:ffff:ffff
105fc59:6800::/24fc59:68ff:ffff:ffff:ffff:ffff:ffff:ffff
106fc59:6900::/24fc59:69ff:ffff:ffff:ffff:ffff:ffff:ffff
107fc59:6a00::/24fc59:6aff:ffff:ffff:ffff:ffff:ffff:ffff
108fc59:6b00::/24fc59:6bff:ffff:ffff:ffff:ffff:ffff:ffff
109fc59:6c00::/24fc59:6cff:ffff:ffff:ffff:ffff:ffff:ffff
110fc59:6d00::/24fc59:6dff:ffff:ffff:ffff:ffff:ffff:ffff
111fc59:6e00::/24fc59:6eff:ffff:ffff:ffff:ffff:ffff:ffff
112fc59:6f00::/24fc59:6fff:ffff:ffff:ffff:ffff:ffff:ffff
113fc59:7000::/24fc59:70ff:ffff:ffff:ffff:ffff:ffff:ffff
114fc59:7100::/24fc59:71ff:ffff:ffff:ffff:ffff:ffff:ffff
115fc59:7200::/24fc59:72ff:ffff:ffff:ffff:ffff:ffff:ffff
116fc59:7300::/24fc59:73ff:ffff:ffff:ffff:ffff:ffff:ffff
117fc59:7400::/24fc59:74ff:ffff:ffff:ffff:ffff:ffff:ffff
118fc59:7500::/24fc59:75ff:ffff:ffff:ffff:ffff:ffff:ffff
119fc59:7600::/24fc59:76ff:ffff:ffff:ffff:ffff:ffff:ffff
120fc59:7700::/24fc59:77ff:ffff:ffff:ffff:ffff:ffff:ffff
121fc59:7800::/24fc59:78ff:ffff:ffff:ffff:ffff:ffff:ffff
122fc59:7900::/24fc59:79ff:ffff:ffff:ffff:ffff:ffff:ffff
123fc59:7a00::/24fc59:7aff:ffff:ffff:ffff:ffff:ffff:ffff
124fc59:7b00::/24fc59:7bff:ffff:ffff:ffff:ffff:ffff:ffff
125fc59:7c00::/24fc59:7cff:ffff:ffff:ffff:ffff:ffff:ffff
126fc59:7d00::/24fc59:7dff:ffff:ffff:ffff:ffff:ffff:ffff
127fc59:7e00::/24fc59:7eff:ffff:ffff:ffff:ffff:ffff:ffff
128fc59:7f00::/24fc59:7fff:ffff:ffff:ffff:ffff:ffff:ffff
129fc59:8000::/24fc59:80ff:ffff:ffff:ffff:ffff:ffff:ffff
130fc59:8100::/24fc59:81ff:ffff:ffff:ffff:ffff:ffff:ffff
131fc59:8200::/24fc59:82ff:ffff:ffff:ffff:ffff:ffff:ffff
132fc59:8300::/24fc59:83ff:ffff:ffff:ffff:ffff:ffff:ffff
133fc59:8400::/24fc59:84ff:ffff:ffff:ffff:ffff:ffff:ffff
134fc59:8500::/24fc59:85ff:ffff:ffff:ffff:ffff:ffff:ffff
135fc59:8600::/24fc59:86ff:ffff:ffff:ffff:ffff:ffff:ffff
136fc59:8700::/24fc59:87ff:ffff:ffff:ffff:ffff:ffff:ffff
137fc59:8800::/24fc59:88ff:ffff:ffff:ffff:ffff:ffff:ffff
138fc59:8900::/24fc59:89ff:ffff:ffff:ffff:ffff:ffff:ffff
139fc59:8a00::/24fc59:8aff:ffff:ffff:ffff:ffff:ffff:ffff
140fc59:8b00::/24fc59:8bff:ffff:ffff:ffff:ffff:ffff:ffff
141fc59:8c00::/24fc59:8cff:ffff:ffff:ffff:ffff:ffff:ffff
142fc59:8d00::/24fc59:8dff:ffff:ffff:ffff:ffff:ffff:ffff
143fc59:8e00::/24fc59:8eff:ffff:ffff:ffff:ffff:ffff:ffff
144fc59:8f00::/24fc59:8fff:ffff:ffff:ffff:ffff:ffff:ffff
145fc59:9000::/24fc59:90ff:ffff:ffff:ffff:ffff:ffff:ffff
146fc59:9100::/24fc59:91ff:ffff:ffff:ffff:ffff:ffff:ffff
147fc59:9200::/24fc59:92ff:ffff:ffff:ffff:ffff:ffff:ffff
148fc59:9300::/24fc59:93ff:ffff:ffff:ffff:ffff:ffff:ffff
149fc59:9400::/24fc59:94ff:ffff:ffff:ffff:ffff:ffff:ffff
150fc59:9500::/24fc59:95ff:ffff:ffff:ffff:ffff:ffff:ffff
151fc59:9600::/24fc59:96ff:ffff:ffff:ffff:ffff:ffff:ffff
152fc59:9700::/24fc59:97ff:ffff:ffff:ffff:ffff:ffff:ffff
153fc59:9800::/24fc59:98ff:ffff:ffff:ffff:ffff:ffff:ffff
154fc59:9900::/24fc59:99ff:ffff:ffff:ffff:ffff:ffff:ffff
155fc59:9a00::/24fc59:9aff:ffff:ffff:ffff:ffff:ffff:ffff
156fc59:9b00::/24fc59:9bff:ffff:ffff:ffff:ffff:ffff:ffff
157fc59:9c00::/24fc59:9cff:ffff:ffff:ffff:ffff:ffff:ffff
158fc59:9d00::/24fc59:9dff:ffff:ffff:ffff:ffff:ffff:ffff
159fc59:9e00::/24fc59:9eff:ffff:ffff:ffff:ffff:ffff:ffff
160fc59:9f00::/24fc59:9fff:ffff:ffff:ffff:ffff:ffff:ffff
161fc59:a000::/24fc59:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
162fc59:a100::/24fc59:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
163fc59:a200::/24fc59:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
164fc59:a300::/24fc59:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
165fc59:a400::/24fc59:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
166fc59:a500::/24fc59:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
167fc59:a600::/24fc59:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
168fc59:a700::/24fc59:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
169fc59:a800::/24fc59:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
170fc59:a900::/24fc59:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
171fc59:aa00::/24fc59:aaff:ffff:ffff:ffff:ffff:ffff:ffff
172fc59:ab00::/24fc59:abff:ffff:ffff:ffff:ffff:ffff:ffff
173fc59:ac00::/24fc59:acff:ffff:ffff:ffff:ffff:ffff:ffff
174fc59:ad00::/24fc59:adff:ffff:ffff:ffff:ffff:ffff:ffff
175fc59:ae00::/24fc59:aeff:ffff:ffff:ffff:ffff:ffff:ffff
176fc59:af00::/24fc59:afff:ffff:ffff:ffff:ffff:ffff:ffff
177fc59:b000::/24fc59:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
178fc59:b100::/24fc59:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
179fc59:b200::/24fc59:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
180fc59:b300::/24fc59:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
181fc59:b400::/24fc59:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
182fc59:b500::/24fc59:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
183fc59:b600::/24fc59:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
184fc59:b700::/24fc59:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
185fc59:b800::/24fc59:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
186fc59:b900::/24fc59:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
187fc59:ba00::/24fc59:baff:ffff:ffff:ffff:ffff:ffff:ffff
188fc59:bb00::/24fc59:bbff:ffff:ffff:ffff:ffff:ffff:ffff
189fc59:bc00::/24fc59:bcff:ffff:ffff:ffff:ffff:ffff:ffff
190fc59:bd00::/24fc59:bdff:ffff:ffff:ffff:ffff:ffff:ffff
191fc59:be00::/24fc59:beff:ffff:ffff:ffff:ffff:ffff:ffff
192fc59:bf00::/24fc59:bfff:ffff:ffff:ffff:ffff:ffff:ffff
193fc59:c000::/24fc59:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
194fc59:c100::/24fc59:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
195fc59:c200::/24fc59:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
196fc59:c300::/24fc59:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
197fc59:c400::/24fc59:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
198fc59:c500::/24fc59:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
199fc59:c600::/24fc59:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
200fc59:c700::/24fc59:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
201fc59:c800::/24fc59:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
202fc59:c900::/24fc59:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
203fc59:ca00::/24fc59:caff:ffff:ffff:ffff:ffff:ffff:ffff
204fc59:cb00::/24fc59:cbff:ffff:ffff:ffff:ffff:ffff:ffff
205fc59:cc00::/24fc59:ccff:ffff:ffff:ffff:ffff:ffff:ffff
206fc59:cd00::/24fc59:cdff:ffff:ffff:ffff:ffff:ffff:ffff
207fc59:ce00::/24fc59:ceff:ffff:ffff:ffff:ffff:ffff:ffff
208fc59:cf00::/24fc59:cfff:ffff:ffff:ffff:ffff:ffff:ffff
209fc59:d000::/24fc59:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
210fc59:d100::/24fc59:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
211fc59:d200::/24fc59:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
212fc59:d300::/24fc59:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
213fc59:d400::/24fc59:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
214fc59:d500::/24fc59:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
215fc59:d600::/24fc59:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
216fc59:d700::/24fc59:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
217fc59:d800::/24fc59:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
218fc59:d900::/24fc59:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
219fc59:da00::/24fc59:daff:ffff:ffff:ffff:ffff:ffff:ffff
220fc59:db00::/24fc59:dbff:ffff:ffff:ffff:ffff:ffff:ffff
221fc59:dc00::/24fc59:dcff:ffff:ffff:ffff:ffff:ffff:ffff
222fc59:dd00::/24fc59:ddff:ffff:ffff:ffff:ffff:ffff:ffff
223fc59:de00::/24fc59:deff:ffff:ffff:ffff:ffff:ffff:ffff
224fc59:df00::/24fc59:dfff:ffff:ffff:ffff:ffff:ffff:ffff
225fc59:e000::/24fc59:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
226fc59:e100::/24fc59:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
227fc59:e200::/24fc59:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
228fc59:e300::/24fc59:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
229fc59:e400::/24fc59:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
230fc59:e500::/24fc59:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
231fc59:e600::/24fc59:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
232fc59:e700::/24fc59:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
233fc59:e800::/24fc59:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
234fc59:e900::/24fc59:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
235fc59:ea00::/24fc59:eaff:ffff:ffff:ffff:ffff:ffff:ffff
236fc59:eb00::/24fc59:ebff:ffff:ffff:ffff:ffff:ffff:ffff
237fc59:ec00::/24fc59:ecff:ffff:ffff:ffff:ffff:ffff:ffff
238fc59:ed00::/24fc59:edff:ffff:ffff:ffff:ffff:ffff:ffff
239fc59:ee00::/24fc59:eeff:ffff:ffff:ffff:ffff:ffff:ffff
240fc59:ef00::/24fc59:efff:ffff:ffff:ffff:ffff:ffff:ffff
241fc59:f000::/24fc59:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
242fc59:f100::/24fc59:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
243fc59:f200::/24fc59:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
244fc59:f300::/24fc59:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
245fc59:f400::/24fc59:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
246fc59:f500::/24fc59:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
247fc59:f600::/24fc59:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
248fc59:f700::/24fc59:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
249fc59:f800::/24fc59:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
250fc59:f900::/24fc59:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
251fc59:fa00::/24fc59:faff:ffff:ffff:ffff:ffff:ffff:ffff
252fc59:fb00::/24fc59:fbff:ffff:ffff:ffff:ffff:ffff:ffff
253fc59:fc00::/24fc59:fcff:ffff:ffff:ffff:ffff:ffff:ffff
254fc59:fd00::/24fc59:fdff:ffff:ffff:ffff:ffff:ffff:ffff
255fc59:fe00::/24fc59:feff:ffff:ffff:ffff:ffff:ffff:ffff
256fc59:ff00::/24fc59: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.