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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
ff98::/16
First address
ff98::
Last address
ff98: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
ff98:0000:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
8.9.f.f.ip6.arpa
Split into smaller subnets/24
/17 (2)/18 (4)/19 (8)/20 (16)/24 (256)/28 (4,096)/32 (65,536)

ff98::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
1ff98::/24ff98:ff:ffff:ffff:ffff:ffff:ffff:ffff
2ff98:100::/24ff98:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3ff98:200::/24ff98:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4ff98:300::/24ff98:3ff:ffff:ffff:ffff:ffff:ffff:ffff
5ff98:400::/24ff98:4ff:ffff:ffff:ffff:ffff:ffff:ffff
6ff98:500::/24ff98:5ff:ffff:ffff:ffff:ffff:ffff:ffff
7ff98:600::/24ff98:6ff:ffff:ffff:ffff:ffff:ffff:ffff
8ff98:700::/24ff98:7ff:ffff:ffff:ffff:ffff:ffff:ffff
9ff98:800::/24ff98:8ff:ffff:ffff:ffff:ffff:ffff:ffff
10ff98:900::/24ff98:9ff:ffff:ffff:ffff:ffff:ffff:ffff
11ff98:a00::/24ff98:aff:ffff:ffff:ffff:ffff:ffff:ffff
12ff98:b00::/24ff98:bff:ffff:ffff:ffff:ffff:ffff:ffff
13ff98:c00::/24ff98:cff:ffff:ffff:ffff:ffff:ffff:ffff
14ff98:d00::/24ff98:dff:ffff:ffff:ffff:ffff:ffff:ffff
15ff98:e00::/24ff98:eff:ffff:ffff:ffff:ffff:ffff:ffff
16ff98:f00::/24ff98:fff:ffff:ffff:ffff:ffff:ffff:ffff
17ff98:1000::/24ff98:10ff:ffff:ffff:ffff:ffff:ffff:ffff
18ff98:1100::/24ff98:11ff:ffff:ffff:ffff:ffff:ffff:ffff
19ff98:1200::/24ff98:12ff:ffff:ffff:ffff:ffff:ffff:ffff
20ff98:1300::/24ff98:13ff:ffff:ffff:ffff:ffff:ffff:ffff
21ff98:1400::/24ff98:14ff:ffff:ffff:ffff:ffff:ffff:ffff
22ff98:1500::/24ff98:15ff:ffff:ffff:ffff:ffff:ffff:ffff
23ff98:1600::/24ff98:16ff:ffff:ffff:ffff:ffff:ffff:ffff
24ff98:1700::/24ff98:17ff:ffff:ffff:ffff:ffff:ffff:ffff
25ff98:1800::/24ff98:18ff:ffff:ffff:ffff:ffff:ffff:ffff
26ff98:1900::/24ff98:19ff:ffff:ffff:ffff:ffff:ffff:ffff
27ff98:1a00::/24ff98:1aff:ffff:ffff:ffff:ffff:ffff:ffff
28ff98:1b00::/24ff98:1bff:ffff:ffff:ffff:ffff:ffff:ffff
29ff98:1c00::/24ff98:1cff:ffff:ffff:ffff:ffff:ffff:ffff
30ff98:1d00::/24ff98:1dff:ffff:ffff:ffff:ffff:ffff:ffff
31ff98:1e00::/24ff98:1eff:ffff:ffff:ffff:ffff:ffff:ffff
32ff98:1f00::/24ff98:1fff:ffff:ffff:ffff:ffff:ffff:ffff
33ff98:2000::/24ff98:20ff:ffff:ffff:ffff:ffff:ffff:ffff
34ff98:2100::/24ff98:21ff:ffff:ffff:ffff:ffff:ffff:ffff
35ff98:2200::/24ff98:22ff:ffff:ffff:ffff:ffff:ffff:ffff
36ff98:2300::/24ff98:23ff:ffff:ffff:ffff:ffff:ffff:ffff
37ff98:2400::/24ff98:24ff:ffff:ffff:ffff:ffff:ffff:ffff
38ff98:2500::/24ff98:25ff:ffff:ffff:ffff:ffff:ffff:ffff
39ff98:2600::/24ff98:26ff:ffff:ffff:ffff:ffff:ffff:ffff
40ff98:2700::/24ff98:27ff:ffff:ffff:ffff:ffff:ffff:ffff
41ff98:2800::/24ff98:28ff:ffff:ffff:ffff:ffff:ffff:ffff
42ff98:2900::/24ff98:29ff:ffff:ffff:ffff:ffff:ffff:ffff
43ff98:2a00::/24ff98:2aff:ffff:ffff:ffff:ffff:ffff:ffff
44ff98:2b00::/24ff98:2bff:ffff:ffff:ffff:ffff:ffff:ffff
45ff98:2c00::/24ff98:2cff:ffff:ffff:ffff:ffff:ffff:ffff
46ff98:2d00::/24ff98:2dff:ffff:ffff:ffff:ffff:ffff:ffff
47ff98:2e00::/24ff98:2eff:ffff:ffff:ffff:ffff:ffff:ffff
48ff98:2f00::/24ff98:2fff:ffff:ffff:ffff:ffff:ffff:ffff
49ff98:3000::/24ff98:30ff:ffff:ffff:ffff:ffff:ffff:ffff
50ff98:3100::/24ff98:31ff:ffff:ffff:ffff:ffff:ffff:ffff
51ff98:3200::/24ff98:32ff:ffff:ffff:ffff:ffff:ffff:ffff
52ff98:3300::/24ff98:33ff:ffff:ffff:ffff:ffff:ffff:ffff
53ff98:3400::/24ff98:34ff:ffff:ffff:ffff:ffff:ffff:ffff
54ff98:3500::/24ff98:35ff:ffff:ffff:ffff:ffff:ffff:ffff
55ff98:3600::/24ff98:36ff:ffff:ffff:ffff:ffff:ffff:ffff
56ff98:3700::/24ff98:37ff:ffff:ffff:ffff:ffff:ffff:ffff
57ff98:3800::/24ff98:38ff:ffff:ffff:ffff:ffff:ffff:ffff
58ff98:3900::/24ff98:39ff:ffff:ffff:ffff:ffff:ffff:ffff
59ff98:3a00::/24ff98:3aff:ffff:ffff:ffff:ffff:ffff:ffff
60ff98:3b00::/24ff98:3bff:ffff:ffff:ffff:ffff:ffff:ffff
61ff98:3c00::/24ff98:3cff:ffff:ffff:ffff:ffff:ffff:ffff
62ff98:3d00::/24ff98:3dff:ffff:ffff:ffff:ffff:ffff:ffff
63ff98:3e00::/24ff98:3eff:ffff:ffff:ffff:ffff:ffff:ffff
64ff98:3f00::/24ff98:3fff:ffff:ffff:ffff:ffff:ffff:ffff
65ff98:4000::/24ff98:40ff:ffff:ffff:ffff:ffff:ffff:ffff
66ff98:4100::/24ff98:41ff:ffff:ffff:ffff:ffff:ffff:ffff
67ff98:4200::/24ff98:42ff:ffff:ffff:ffff:ffff:ffff:ffff
68ff98:4300::/24ff98:43ff:ffff:ffff:ffff:ffff:ffff:ffff
69ff98:4400::/24ff98:44ff:ffff:ffff:ffff:ffff:ffff:ffff
70ff98:4500::/24ff98:45ff:ffff:ffff:ffff:ffff:ffff:ffff
71ff98:4600::/24ff98:46ff:ffff:ffff:ffff:ffff:ffff:ffff
72ff98:4700::/24ff98:47ff:ffff:ffff:ffff:ffff:ffff:ffff
73ff98:4800::/24ff98:48ff:ffff:ffff:ffff:ffff:ffff:ffff
74ff98:4900::/24ff98:49ff:ffff:ffff:ffff:ffff:ffff:ffff
75ff98:4a00::/24ff98:4aff:ffff:ffff:ffff:ffff:ffff:ffff
76ff98:4b00::/24ff98:4bff:ffff:ffff:ffff:ffff:ffff:ffff
77ff98:4c00::/24ff98:4cff:ffff:ffff:ffff:ffff:ffff:ffff
78ff98:4d00::/24ff98:4dff:ffff:ffff:ffff:ffff:ffff:ffff
79ff98:4e00::/24ff98:4eff:ffff:ffff:ffff:ffff:ffff:ffff
80ff98:4f00::/24ff98:4fff:ffff:ffff:ffff:ffff:ffff:ffff
81ff98:5000::/24ff98:50ff:ffff:ffff:ffff:ffff:ffff:ffff
82ff98:5100::/24ff98:51ff:ffff:ffff:ffff:ffff:ffff:ffff
83ff98:5200::/24ff98:52ff:ffff:ffff:ffff:ffff:ffff:ffff
84ff98:5300::/24ff98:53ff:ffff:ffff:ffff:ffff:ffff:ffff
85ff98:5400::/24ff98:54ff:ffff:ffff:ffff:ffff:ffff:ffff
86ff98:5500::/24ff98:55ff:ffff:ffff:ffff:ffff:ffff:ffff
87ff98:5600::/24ff98:56ff:ffff:ffff:ffff:ffff:ffff:ffff
88ff98:5700::/24ff98:57ff:ffff:ffff:ffff:ffff:ffff:ffff
89ff98:5800::/24ff98:58ff:ffff:ffff:ffff:ffff:ffff:ffff
90ff98:5900::/24ff98:59ff:ffff:ffff:ffff:ffff:ffff:ffff
91ff98:5a00::/24ff98:5aff:ffff:ffff:ffff:ffff:ffff:ffff
92ff98:5b00::/24ff98:5bff:ffff:ffff:ffff:ffff:ffff:ffff
93ff98:5c00::/24ff98:5cff:ffff:ffff:ffff:ffff:ffff:ffff
94ff98:5d00::/24ff98:5dff:ffff:ffff:ffff:ffff:ffff:ffff
95ff98:5e00::/24ff98:5eff:ffff:ffff:ffff:ffff:ffff:ffff
96ff98:5f00::/24ff98:5fff:ffff:ffff:ffff:ffff:ffff:ffff
97ff98:6000::/24ff98:60ff:ffff:ffff:ffff:ffff:ffff:ffff
98ff98:6100::/24ff98:61ff:ffff:ffff:ffff:ffff:ffff:ffff
99ff98:6200::/24ff98:62ff:ffff:ffff:ffff:ffff:ffff:ffff
100ff98:6300::/24ff98:63ff:ffff:ffff:ffff:ffff:ffff:ffff
101ff98:6400::/24ff98:64ff:ffff:ffff:ffff:ffff:ffff:ffff
102ff98:6500::/24ff98:65ff:ffff:ffff:ffff:ffff:ffff:ffff
103ff98:6600::/24ff98:66ff:ffff:ffff:ffff:ffff:ffff:ffff
104ff98:6700::/24ff98:67ff:ffff:ffff:ffff:ffff:ffff:ffff
105ff98:6800::/24ff98:68ff:ffff:ffff:ffff:ffff:ffff:ffff
106ff98:6900::/24ff98:69ff:ffff:ffff:ffff:ffff:ffff:ffff
107ff98:6a00::/24ff98:6aff:ffff:ffff:ffff:ffff:ffff:ffff
108ff98:6b00::/24ff98:6bff:ffff:ffff:ffff:ffff:ffff:ffff
109ff98:6c00::/24ff98:6cff:ffff:ffff:ffff:ffff:ffff:ffff
110ff98:6d00::/24ff98:6dff:ffff:ffff:ffff:ffff:ffff:ffff
111ff98:6e00::/24ff98:6eff:ffff:ffff:ffff:ffff:ffff:ffff
112ff98:6f00::/24ff98:6fff:ffff:ffff:ffff:ffff:ffff:ffff
113ff98:7000::/24ff98:70ff:ffff:ffff:ffff:ffff:ffff:ffff
114ff98:7100::/24ff98:71ff:ffff:ffff:ffff:ffff:ffff:ffff
115ff98:7200::/24ff98:72ff:ffff:ffff:ffff:ffff:ffff:ffff
116ff98:7300::/24ff98:73ff:ffff:ffff:ffff:ffff:ffff:ffff
117ff98:7400::/24ff98:74ff:ffff:ffff:ffff:ffff:ffff:ffff
118ff98:7500::/24ff98:75ff:ffff:ffff:ffff:ffff:ffff:ffff
119ff98:7600::/24ff98:76ff:ffff:ffff:ffff:ffff:ffff:ffff
120ff98:7700::/24ff98:77ff:ffff:ffff:ffff:ffff:ffff:ffff
121ff98:7800::/24ff98:78ff:ffff:ffff:ffff:ffff:ffff:ffff
122ff98:7900::/24ff98:79ff:ffff:ffff:ffff:ffff:ffff:ffff
123ff98:7a00::/24ff98:7aff:ffff:ffff:ffff:ffff:ffff:ffff
124ff98:7b00::/24ff98:7bff:ffff:ffff:ffff:ffff:ffff:ffff
125ff98:7c00::/24ff98:7cff:ffff:ffff:ffff:ffff:ffff:ffff
126ff98:7d00::/24ff98:7dff:ffff:ffff:ffff:ffff:ffff:ffff
127ff98:7e00::/24ff98:7eff:ffff:ffff:ffff:ffff:ffff:ffff
128ff98:7f00::/24ff98:7fff:ffff:ffff:ffff:ffff:ffff:ffff
129ff98:8000::/24ff98:80ff:ffff:ffff:ffff:ffff:ffff:ffff
130ff98:8100::/24ff98:81ff:ffff:ffff:ffff:ffff:ffff:ffff
131ff98:8200::/24ff98:82ff:ffff:ffff:ffff:ffff:ffff:ffff
132ff98:8300::/24ff98:83ff:ffff:ffff:ffff:ffff:ffff:ffff
133ff98:8400::/24ff98:84ff:ffff:ffff:ffff:ffff:ffff:ffff
134ff98:8500::/24ff98:85ff:ffff:ffff:ffff:ffff:ffff:ffff
135ff98:8600::/24ff98:86ff:ffff:ffff:ffff:ffff:ffff:ffff
136ff98:8700::/24ff98:87ff:ffff:ffff:ffff:ffff:ffff:ffff
137ff98:8800::/24ff98:88ff:ffff:ffff:ffff:ffff:ffff:ffff
138ff98:8900::/24ff98:89ff:ffff:ffff:ffff:ffff:ffff:ffff
139ff98:8a00::/24ff98:8aff:ffff:ffff:ffff:ffff:ffff:ffff
140ff98:8b00::/24ff98:8bff:ffff:ffff:ffff:ffff:ffff:ffff
141ff98:8c00::/24ff98:8cff:ffff:ffff:ffff:ffff:ffff:ffff
142ff98:8d00::/24ff98:8dff:ffff:ffff:ffff:ffff:ffff:ffff
143ff98:8e00::/24ff98:8eff:ffff:ffff:ffff:ffff:ffff:ffff
144ff98:8f00::/24ff98:8fff:ffff:ffff:ffff:ffff:ffff:ffff
145ff98:9000::/24ff98:90ff:ffff:ffff:ffff:ffff:ffff:ffff
146ff98:9100::/24ff98:91ff:ffff:ffff:ffff:ffff:ffff:ffff
147ff98:9200::/24ff98:92ff:ffff:ffff:ffff:ffff:ffff:ffff
148ff98:9300::/24ff98:93ff:ffff:ffff:ffff:ffff:ffff:ffff
149ff98:9400::/24ff98:94ff:ffff:ffff:ffff:ffff:ffff:ffff
150ff98:9500::/24ff98:95ff:ffff:ffff:ffff:ffff:ffff:ffff
151ff98:9600::/24ff98:96ff:ffff:ffff:ffff:ffff:ffff:ffff
152ff98:9700::/24ff98:97ff:ffff:ffff:ffff:ffff:ffff:ffff
153ff98:9800::/24ff98:98ff:ffff:ffff:ffff:ffff:ffff:ffff
154ff98:9900::/24ff98:99ff:ffff:ffff:ffff:ffff:ffff:ffff
155ff98:9a00::/24ff98:9aff:ffff:ffff:ffff:ffff:ffff:ffff
156ff98:9b00::/24ff98:9bff:ffff:ffff:ffff:ffff:ffff:ffff
157ff98:9c00::/24ff98:9cff:ffff:ffff:ffff:ffff:ffff:ffff
158ff98:9d00::/24ff98:9dff:ffff:ffff:ffff:ffff:ffff:ffff
159ff98:9e00::/24ff98:9eff:ffff:ffff:ffff:ffff:ffff:ffff
160ff98:9f00::/24ff98:9fff:ffff:ffff:ffff:ffff:ffff:ffff
161ff98:a000::/24ff98:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
162ff98:a100::/24ff98:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
163ff98:a200::/24ff98:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
164ff98:a300::/24ff98:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
165ff98:a400::/24ff98:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
166ff98:a500::/24ff98:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
167ff98:a600::/24ff98:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
168ff98:a700::/24ff98:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
169ff98:a800::/24ff98:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
170ff98:a900::/24ff98:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
171ff98:aa00::/24ff98:aaff:ffff:ffff:ffff:ffff:ffff:ffff
172ff98:ab00::/24ff98:abff:ffff:ffff:ffff:ffff:ffff:ffff
173ff98:ac00::/24ff98:acff:ffff:ffff:ffff:ffff:ffff:ffff
174ff98:ad00::/24ff98:adff:ffff:ffff:ffff:ffff:ffff:ffff
175ff98:ae00::/24ff98:aeff:ffff:ffff:ffff:ffff:ffff:ffff
176ff98:af00::/24ff98:afff:ffff:ffff:ffff:ffff:ffff:ffff
177ff98:b000::/24ff98:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
178ff98:b100::/24ff98:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
179ff98:b200::/24ff98:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
180ff98:b300::/24ff98:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
181ff98:b400::/24ff98:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
182ff98:b500::/24ff98:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
183ff98:b600::/24ff98:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
184ff98:b700::/24ff98:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
185ff98:b800::/24ff98:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
186ff98:b900::/24ff98:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
187ff98:ba00::/24ff98:baff:ffff:ffff:ffff:ffff:ffff:ffff
188ff98:bb00::/24ff98:bbff:ffff:ffff:ffff:ffff:ffff:ffff
189ff98:bc00::/24ff98:bcff:ffff:ffff:ffff:ffff:ffff:ffff
190ff98:bd00::/24ff98:bdff:ffff:ffff:ffff:ffff:ffff:ffff
191ff98:be00::/24ff98:beff:ffff:ffff:ffff:ffff:ffff:ffff
192ff98:bf00::/24ff98:bfff:ffff:ffff:ffff:ffff:ffff:ffff
193ff98:c000::/24ff98:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
194ff98:c100::/24ff98:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
195ff98:c200::/24ff98:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
196ff98:c300::/24ff98:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
197ff98:c400::/24ff98:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
198ff98:c500::/24ff98:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
199ff98:c600::/24ff98:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
200ff98:c700::/24ff98:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
201ff98:c800::/24ff98:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
202ff98:c900::/24ff98:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
203ff98:ca00::/24ff98:caff:ffff:ffff:ffff:ffff:ffff:ffff
204ff98:cb00::/24ff98:cbff:ffff:ffff:ffff:ffff:ffff:ffff
205ff98:cc00::/24ff98:ccff:ffff:ffff:ffff:ffff:ffff:ffff
206ff98:cd00::/24ff98:cdff:ffff:ffff:ffff:ffff:ffff:ffff
207ff98:ce00::/24ff98:ceff:ffff:ffff:ffff:ffff:ffff:ffff
208ff98:cf00::/24ff98:cfff:ffff:ffff:ffff:ffff:ffff:ffff
209ff98:d000::/24ff98:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
210ff98:d100::/24ff98:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
211ff98:d200::/24ff98:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
212ff98:d300::/24ff98:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
213ff98:d400::/24ff98:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
214ff98:d500::/24ff98:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
215ff98:d600::/24ff98:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
216ff98:d700::/24ff98:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
217ff98:d800::/24ff98:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
218ff98:d900::/24ff98:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
219ff98:da00::/24ff98:daff:ffff:ffff:ffff:ffff:ffff:ffff
220ff98:db00::/24ff98:dbff:ffff:ffff:ffff:ffff:ffff:ffff
221ff98:dc00::/24ff98:dcff:ffff:ffff:ffff:ffff:ffff:ffff
222ff98:dd00::/24ff98:ddff:ffff:ffff:ffff:ffff:ffff:ffff
223ff98:de00::/24ff98:deff:ffff:ffff:ffff:ffff:ffff:ffff
224ff98:df00::/24ff98:dfff:ffff:ffff:ffff:ffff:ffff:ffff
225ff98:e000::/24ff98:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
226ff98:e100::/24ff98:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
227ff98:e200::/24ff98:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
228ff98:e300::/24ff98:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
229ff98:e400::/24ff98:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
230ff98:e500::/24ff98:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
231ff98:e600::/24ff98:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
232ff98:e700::/24ff98:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
233ff98:e800::/24ff98:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
234ff98:e900::/24ff98:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
235ff98:ea00::/24ff98:eaff:ffff:ffff:ffff:ffff:ffff:ffff
236ff98:eb00::/24ff98:ebff:ffff:ffff:ffff:ffff:ffff:ffff
237ff98:ec00::/24ff98:ecff:ffff:ffff:ffff:ffff:ffff:ffff
238ff98:ed00::/24ff98:edff:ffff:ffff:ffff:ffff:ffff:ffff
239ff98:ee00::/24ff98:eeff:ffff:ffff:ffff:ffff:ffff:ffff
240ff98:ef00::/24ff98:efff:ffff:ffff:ffff:ffff:ffff:ffff
241ff98:f000::/24ff98:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
242ff98:f100::/24ff98:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
243ff98:f200::/24ff98:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
244ff98:f300::/24ff98:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
245ff98:f400::/24ff98:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
246ff98:f500::/24ff98:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
247ff98:f600::/24ff98:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
248ff98:f700::/24ff98:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
249ff98:f800::/24ff98:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
250ff98:f900::/24ff98:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
251ff98:fa00::/24ff98:faff:ffff:ffff:ffff:ffff:ffff:ffff
252ff98:fb00::/24ff98:fbff:ffff:ffff:ffff:ffff:ffff:ffff
253ff98:fc00::/24ff98:fcff:ffff:ffff:ffff:ffff:ffff:ffff
254ff98:fd00::/24ff98:fdff:ffff:ffff:ffff:ffff:ffff:ffff
255ff98:fe00::/24ff98:feff:ffff:ffff:ffff:ffff:ffff:ffff
256ff98:ff00::/24ff98: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.