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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
fc98::/16
First address
fc98::
Last address
fc98: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
fc98:0000:0000:0000:0000:0000:0000:0000
Type
Unique local (ULA) fc00::/7
Private IPv6, like RFC 1918; usually fd00::/8
Reverse DNS zone
8.9.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)

fc98::/16 makes 256 subnets of /24.

Subnets
#SubnetLast address
1fc98::/24fc98:ff:ffff:ffff:ffff:ffff:ffff:ffff
2fc98:100::/24fc98:1ff:ffff:ffff:ffff:ffff:ffff:ffff
3fc98:200::/24fc98:2ff:ffff:ffff:ffff:ffff:ffff:ffff
4fc98:300::/24fc98:3ff:ffff:ffff:ffff:ffff:ffff:ffff
5fc98:400::/24fc98:4ff:ffff:ffff:ffff:ffff:ffff:ffff
6fc98:500::/24fc98:5ff:ffff:ffff:ffff:ffff:ffff:ffff
7fc98:600::/24fc98:6ff:ffff:ffff:ffff:ffff:ffff:ffff
8fc98:700::/24fc98:7ff:ffff:ffff:ffff:ffff:ffff:ffff
9fc98:800::/24fc98:8ff:ffff:ffff:ffff:ffff:ffff:ffff
10fc98:900::/24fc98:9ff:ffff:ffff:ffff:ffff:ffff:ffff
11fc98:a00::/24fc98:aff:ffff:ffff:ffff:ffff:ffff:ffff
12fc98:b00::/24fc98:bff:ffff:ffff:ffff:ffff:ffff:ffff
13fc98:c00::/24fc98:cff:ffff:ffff:ffff:ffff:ffff:ffff
14fc98:d00::/24fc98:dff:ffff:ffff:ffff:ffff:ffff:ffff
15fc98:e00::/24fc98:eff:ffff:ffff:ffff:ffff:ffff:ffff
16fc98:f00::/24fc98:fff:ffff:ffff:ffff:ffff:ffff:ffff
17fc98:1000::/24fc98:10ff:ffff:ffff:ffff:ffff:ffff:ffff
18fc98:1100::/24fc98:11ff:ffff:ffff:ffff:ffff:ffff:ffff
19fc98:1200::/24fc98:12ff:ffff:ffff:ffff:ffff:ffff:ffff
20fc98:1300::/24fc98:13ff:ffff:ffff:ffff:ffff:ffff:ffff
21fc98:1400::/24fc98:14ff:ffff:ffff:ffff:ffff:ffff:ffff
22fc98:1500::/24fc98:15ff:ffff:ffff:ffff:ffff:ffff:ffff
23fc98:1600::/24fc98:16ff:ffff:ffff:ffff:ffff:ffff:ffff
24fc98:1700::/24fc98:17ff:ffff:ffff:ffff:ffff:ffff:ffff
25fc98:1800::/24fc98:18ff:ffff:ffff:ffff:ffff:ffff:ffff
26fc98:1900::/24fc98:19ff:ffff:ffff:ffff:ffff:ffff:ffff
27fc98:1a00::/24fc98:1aff:ffff:ffff:ffff:ffff:ffff:ffff
28fc98:1b00::/24fc98:1bff:ffff:ffff:ffff:ffff:ffff:ffff
29fc98:1c00::/24fc98:1cff:ffff:ffff:ffff:ffff:ffff:ffff
30fc98:1d00::/24fc98:1dff:ffff:ffff:ffff:ffff:ffff:ffff
31fc98:1e00::/24fc98:1eff:ffff:ffff:ffff:ffff:ffff:ffff
32fc98:1f00::/24fc98:1fff:ffff:ffff:ffff:ffff:ffff:ffff
33fc98:2000::/24fc98:20ff:ffff:ffff:ffff:ffff:ffff:ffff
34fc98:2100::/24fc98:21ff:ffff:ffff:ffff:ffff:ffff:ffff
35fc98:2200::/24fc98:22ff:ffff:ffff:ffff:ffff:ffff:ffff
36fc98:2300::/24fc98:23ff:ffff:ffff:ffff:ffff:ffff:ffff
37fc98:2400::/24fc98:24ff:ffff:ffff:ffff:ffff:ffff:ffff
38fc98:2500::/24fc98:25ff:ffff:ffff:ffff:ffff:ffff:ffff
39fc98:2600::/24fc98:26ff:ffff:ffff:ffff:ffff:ffff:ffff
40fc98:2700::/24fc98:27ff:ffff:ffff:ffff:ffff:ffff:ffff
41fc98:2800::/24fc98:28ff:ffff:ffff:ffff:ffff:ffff:ffff
42fc98:2900::/24fc98:29ff:ffff:ffff:ffff:ffff:ffff:ffff
43fc98:2a00::/24fc98:2aff:ffff:ffff:ffff:ffff:ffff:ffff
44fc98:2b00::/24fc98:2bff:ffff:ffff:ffff:ffff:ffff:ffff
45fc98:2c00::/24fc98:2cff:ffff:ffff:ffff:ffff:ffff:ffff
46fc98:2d00::/24fc98:2dff:ffff:ffff:ffff:ffff:ffff:ffff
47fc98:2e00::/24fc98:2eff:ffff:ffff:ffff:ffff:ffff:ffff
48fc98:2f00::/24fc98:2fff:ffff:ffff:ffff:ffff:ffff:ffff
49fc98:3000::/24fc98:30ff:ffff:ffff:ffff:ffff:ffff:ffff
50fc98:3100::/24fc98:31ff:ffff:ffff:ffff:ffff:ffff:ffff
51fc98:3200::/24fc98:32ff:ffff:ffff:ffff:ffff:ffff:ffff
52fc98:3300::/24fc98:33ff:ffff:ffff:ffff:ffff:ffff:ffff
53fc98:3400::/24fc98:34ff:ffff:ffff:ffff:ffff:ffff:ffff
54fc98:3500::/24fc98:35ff:ffff:ffff:ffff:ffff:ffff:ffff
55fc98:3600::/24fc98:36ff:ffff:ffff:ffff:ffff:ffff:ffff
56fc98:3700::/24fc98:37ff:ffff:ffff:ffff:ffff:ffff:ffff
57fc98:3800::/24fc98:38ff:ffff:ffff:ffff:ffff:ffff:ffff
58fc98:3900::/24fc98:39ff:ffff:ffff:ffff:ffff:ffff:ffff
59fc98:3a00::/24fc98:3aff:ffff:ffff:ffff:ffff:ffff:ffff
60fc98:3b00::/24fc98:3bff:ffff:ffff:ffff:ffff:ffff:ffff
61fc98:3c00::/24fc98:3cff:ffff:ffff:ffff:ffff:ffff:ffff
62fc98:3d00::/24fc98:3dff:ffff:ffff:ffff:ffff:ffff:ffff
63fc98:3e00::/24fc98:3eff:ffff:ffff:ffff:ffff:ffff:ffff
64fc98:3f00::/24fc98:3fff:ffff:ffff:ffff:ffff:ffff:ffff
65fc98:4000::/24fc98:40ff:ffff:ffff:ffff:ffff:ffff:ffff
66fc98:4100::/24fc98:41ff:ffff:ffff:ffff:ffff:ffff:ffff
67fc98:4200::/24fc98:42ff:ffff:ffff:ffff:ffff:ffff:ffff
68fc98:4300::/24fc98:43ff:ffff:ffff:ffff:ffff:ffff:ffff
69fc98:4400::/24fc98:44ff:ffff:ffff:ffff:ffff:ffff:ffff
70fc98:4500::/24fc98:45ff:ffff:ffff:ffff:ffff:ffff:ffff
71fc98:4600::/24fc98:46ff:ffff:ffff:ffff:ffff:ffff:ffff
72fc98:4700::/24fc98:47ff:ffff:ffff:ffff:ffff:ffff:ffff
73fc98:4800::/24fc98:48ff:ffff:ffff:ffff:ffff:ffff:ffff
74fc98:4900::/24fc98:49ff:ffff:ffff:ffff:ffff:ffff:ffff
75fc98:4a00::/24fc98:4aff:ffff:ffff:ffff:ffff:ffff:ffff
76fc98:4b00::/24fc98:4bff:ffff:ffff:ffff:ffff:ffff:ffff
77fc98:4c00::/24fc98:4cff:ffff:ffff:ffff:ffff:ffff:ffff
78fc98:4d00::/24fc98:4dff:ffff:ffff:ffff:ffff:ffff:ffff
79fc98:4e00::/24fc98:4eff:ffff:ffff:ffff:ffff:ffff:ffff
80fc98:4f00::/24fc98:4fff:ffff:ffff:ffff:ffff:ffff:ffff
81fc98:5000::/24fc98:50ff:ffff:ffff:ffff:ffff:ffff:ffff
82fc98:5100::/24fc98:51ff:ffff:ffff:ffff:ffff:ffff:ffff
83fc98:5200::/24fc98:52ff:ffff:ffff:ffff:ffff:ffff:ffff
84fc98:5300::/24fc98:53ff:ffff:ffff:ffff:ffff:ffff:ffff
85fc98:5400::/24fc98:54ff:ffff:ffff:ffff:ffff:ffff:ffff
86fc98:5500::/24fc98:55ff:ffff:ffff:ffff:ffff:ffff:ffff
87fc98:5600::/24fc98:56ff:ffff:ffff:ffff:ffff:ffff:ffff
88fc98:5700::/24fc98:57ff:ffff:ffff:ffff:ffff:ffff:ffff
89fc98:5800::/24fc98:58ff:ffff:ffff:ffff:ffff:ffff:ffff
90fc98:5900::/24fc98:59ff:ffff:ffff:ffff:ffff:ffff:ffff
91fc98:5a00::/24fc98:5aff:ffff:ffff:ffff:ffff:ffff:ffff
92fc98:5b00::/24fc98:5bff:ffff:ffff:ffff:ffff:ffff:ffff
93fc98:5c00::/24fc98:5cff:ffff:ffff:ffff:ffff:ffff:ffff
94fc98:5d00::/24fc98:5dff:ffff:ffff:ffff:ffff:ffff:ffff
95fc98:5e00::/24fc98:5eff:ffff:ffff:ffff:ffff:ffff:ffff
96fc98:5f00::/24fc98:5fff:ffff:ffff:ffff:ffff:ffff:ffff
97fc98:6000::/24fc98:60ff:ffff:ffff:ffff:ffff:ffff:ffff
98fc98:6100::/24fc98:61ff:ffff:ffff:ffff:ffff:ffff:ffff
99fc98:6200::/24fc98:62ff:ffff:ffff:ffff:ffff:ffff:ffff
100fc98:6300::/24fc98:63ff:ffff:ffff:ffff:ffff:ffff:ffff
101fc98:6400::/24fc98:64ff:ffff:ffff:ffff:ffff:ffff:ffff
102fc98:6500::/24fc98:65ff:ffff:ffff:ffff:ffff:ffff:ffff
103fc98:6600::/24fc98:66ff:ffff:ffff:ffff:ffff:ffff:ffff
104fc98:6700::/24fc98:67ff:ffff:ffff:ffff:ffff:ffff:ffff
105fc98:6800::/24fc98:68ff:ffff:ffff:ffff:ffff:ffff:ffff
106fc98:6900::/24fc98:69ff:ffff:ffff:ffff:ffff:ffff:ffff
107fc98:6a00::/24fc98:6aff:ffff:ffff:ffff:ffff:ffff:ffff
108fc98:6b00::/24fc98:6bff:ffff:ffff:ffff:ffff:ffff:ffff
109fc98:6c00::/24fc98:6cff:ffff:ffff:ffff:ffff:ffff:ffff
110fc98:6d00::/24fc98:6dff:ffff:ffff:ffff:ffff:ffff:ffff
111fc98:6e00::/24fc98:6eff:ffff:ffff:ffff:ffff:ffff:ffff
112fc98:6f00::/24fc98:6fff:ffff:ffff:ffff:ffff:ffff:ffff
113fc98:7000::/24fc98:70ff:ffff:ffff:ffff:ffff:ffff:ffff
114fc98:7100::/24fc98:71ff:ffff:ffff:ffff:ffff:ffff:ffff
115fc98:7200::/24fc98:72ff:ffff:ffff:ffff:ffff:ffff:ffff
116fc98:7300::/24fc98:73ff:ffff:ffff:ffff:ffff:ffff:ffff
117fc98:7400::/24fc98:74ff:ffff:ffff:ffff:ffff:ffff:ffff
118fc98:7500::/24fc98:75ff:ffff:ffff:ffff:ffff:ffff:ffff
119fc98:7600::/24fc98:76ff:ffff:ffff:ffff:ffff:ffff:ffff
120fc98:7700::/24fc98:77ff:ffff:ffff:ffff:ffff:ffff:ffff
121fc98:7800::/24fc98:78ff:ffff:ffff:ffff:ffff:ffff:ffff
122fc98:7900::/24fc98:79ff:ffff:ffff:ffff:ffff:ffff:ffff
123fc98:7a00::/24fc98:7aff:ffff:ffff:ffff:ffff:ffff:ffff
124fc98:7b00::/24fc98:7bff:ffff:ffff:ffff:ffff:ffff:ffff
125fc98:7c00::/24fc98:7cff:ffff:ffff:ffff:ffff:ffff:ffff
126fc98:7d00::/24fc98:7dff:ffff:ffff:ffff:ffff:ffff:ffff
127fc98:7e00::/24fc98:7eff:ffff:ffff:ffff:ffff:ffff:ffff
128fc98:7f00::/24fc98:7fff:ffff:ffff:ffff:ffff:ffff:ffff
129fc98:8000::/24fc98:80ff:ffff:ffff:ffff:ffff:ffff:ffff
130fc98:8100::/24fc98:81ff:ffff:ffff:ffff:ffff:ffff:ffff
131fc98:8200::/24fc98:82ff:ffff:ffff:ffff:ffff:ffff:ffff
132fc98:8300::/24fc98:83ff:ffff:ffff:ffff:ffff:ffff:ffff
133fc98:8400::/24fc98:84ff:ffff:ffff:ffff:ffff:ffff:ffff
134fc98:8500::/24fc98:85ff:ffff:ffff:ffff:ffff:ffff:ffff
135fc98:8600::/24fc98:86ff:ffff:ffff:ffff:ffff:ffff:ffff
136fc98:8700::/24fc98:87ff:ffff:ffff:ffff:ffff:ffff:ffff
137fc98:8800::/24fc98:88ff:ffff:ffff:ffff:ffff:ffff:ffff
138fc98:8900::/24fc98:89ff:ffff:ffff:ffff:ffff:ffff:ffff
139fc98:8a00::/24fc98:8aff:ffff:ffff:ffff:ffff:ffff:ffff
140fc98:8b00::/24fc98:8bff:ffff:ffff:ffff:ffff:ffff:ffff
141fc98:8c00::/24fc98:8cff:ffff:ffff:ffff:ffff:ffff:ffff
142fc98:8d00::/24fc98:8dff:ffff:ffff:ffff:ffff:ffff:ffff
143fc98:8e00::/24fc98:8eff:ffff:ffff:ffff:ffff:ffff:ffff
144fc98:8f00::/24fc98:8fff:ffff:ffff:ffff:ffff:ffff:ffff
145fc98:9000::/24fc98:90ff:ffff:ffff:ffff:ffff:ffff:ffff
146fc98:9100::/24fc98:91ff:ffff:ffff:ffff:ffff:ffff:ffff
147fc98:9200::/24fc98:92ff:ffff:ffff:ffff:ffff:ffff:ffff
148fc98:9300::/24fc98:93ff:ffff:ffff:ffff:ffff:ffff:ffff
149fc98:9400::/24fc98:94ff:ffff:ffff:ffff:ffff:ffff:ffff
150fc98:9500::/24fc98:95ff:ffff:ffff:ffff:ffff:ffff:ffff
151fc98:9600::/24fc98:96ff:ffff:ffff:ffff:ffff:ffff:ffff
152fc98:9700::/24fc98:97ff:ffff:ffff:ffff:ffff:ffff:ffff
153fc98:9800::/24fc98:98ff:ffff:ffff:ffff:ffff:ffff:ffff
154fc98:9900::/24fc98:99ff:ffff:ffff:ffff:ffff:ffff:ffff
155fc98:9a00::/24fc98:9aff:ffff:ffff:ffff:ffff:ffff:ffff
156fc98:9b00::/24fc98:9bff:ffff:ffff:ffff:ffff:ffff:ffff
157fc98:9c00::/24fc98:9cff:ffff:ffff:ffff:ffff:ffff:ffff
158fc98:9d00::/24fc98:9dff:ffff:ffff:ffff:ffff:ffff:ffff
159fc98:9e00::/24fc98:9eff:ffff:ffff:ffff:ffff:ffff:ffff
160fc98:9f00::/24fc98:9fff:ffff:ffff:ffff:ffff:ffff:ffff
161fc98:a000::/24fc98:a0ff:ffff:ffff:ffff:ffff:ffff:ffff
162fc98:a100::/24fc98:a1ff:ffff:ffff:ffff:ffff:ffff:ffff
163fc98:a200::/24fc98:a2ff:ffff:ffff:ffff:ffff:ffff:ffff
164fc98:a300::/24fc98:a3ff:ffff:ffff:ffff:ffff:ffff:ffff
165fc98:a400::/24fc98:a4ff:ffff:ffff:ffff:ffff:ffff:ffff
166fc98:a500::/24fc98:a5ff:ffff:ffff:ffff:ffff:ffff:ffff
167fc98:a600::/24fc98:a6ff:ffff:ffff:ffff:ffff:ffff:ffff
168fc98:a700::/24fc98:a7ff:ffff:ffff:ffff:ffff:ffff:ffff
169fc98:a800::/24fc98:a8ff:ffff:ffff:ffff:ffff:ffff:ffff
170fc98:a900::/24fc98:a9ff:ffff:ffff:ffff:ffff:ffff:ffff
171fc98:aa00::/24fc98:aaff:ffff:ffff:ffff:ffff:ffff:ffff
172fc98:ab00::/24fc98:abff:ffff:ffff:ffff:ffff:ffff:ffff
173fc98:ac00::/24fc98:acff:ffff:ffff:ffff:ffff:ffff:ffff
174fc98:ad00::/24fc98:adff:ffff:ffff:ffff:ffff:ffff:ffff
175fc98:ae00::/24fc98:aeff:ffff:ffff:ffff:ffff:ffff:ffff
176fc98:af00::/24fc98:afff:ffff:ffff:ffff:ffff:ffff:ffff
177fc98:b000::/24fc98:b0ff:ffff:ffff:ffff:ffff:ffff:ffff
178fc98:b100::/24fc98:b1ff:ffff:ffff:ffff:ffff:ffff:ffff
179fc98:b200::/24fc98:b2ff:ffff:ffff:ffff:ffff:ffff:ffff
180fc98:b300::/24fc98:b3ff:ffff:ffff:ffff:ffff:ffff:ffff
181fc98:b400::/24fc98:b4ff:ffff:ffff:ffff:ffff:ffff:ffff
182fc98:b500::/24fc98:b5ff:ffff:ffff:ffff:ffff:ffff:ffff
183fc98:b600::/24fc98:b6ff:ffff:ffff:ffff:ffff:ffff:ffff
184fc98:b700::/24fc98:b7ff:ffff:ffff:ffff:ffff:ffff:ffff
185fc98:b800::/24fc98:b8ff:ffff:ffff:ffff:ffff:ffff:ffff
186fc98:b900::/24fc98:b9ff:ffff:ffff:ffff:ffff:ffff:ffff
187fc98:ba00::/24fc98:baff:ffff:ffff:ffff:ffff:ffff:ffff
188fc98:bb00::/24fc98:bbff:ffff:ffff:ffff:ffff:ffff:ffff
189fc98:bc00::/24fc98:bcff:ffff:ffff:ffff:ffff:ffff:ffff
190fc98:bd00::/24fc98:bdff:ffff:ffff:ffff:ffff:ffff:ffff
191fc98:be00::/24fc98:beff:ffff:ffff:ffff:ffff:ffff:ffff
192fc98:bf00::/24fc98:bfff:ffff:ffff:ffff:ffff:ffff:ffff
193fc98:c000::/24fc98:c0ff:ffff:ffff:ffff:ffff:ffff:ffff
194fc98:c100::/24fc98:c1ff:ffff:ffff:ffff:ffff:ffff:ffff
195fc98:c200::/24fc98:c2ff:ffff:ffff:ffff:ffff:ffff:ffff
196fc98:c300::/24fc98:c3ff:ffff:ffff:ffff:ffff:ffff:ffff
197fc98:c400::/24fc98:c4ff:ffff:ffff:ffff:ffff:ffff:ffff
198fc98:c500::/24fc98:c5ff:ffff:ffff:ffff:ffff:ffff:ffff
199fc98:c600::/24fc98:c6ff:ffff:ffff:ffff:ffff:ffff:ffff
200fc98:c700::/24fc98:c7ff:ffff:ffff:ffff:ffff:ffff:ffff
201fc98:c800::/24fc98:c8ff:ffff:ffff:ffff:ffff:ffff:ffff
202fc98:c900::/24fc98:c9ff:ffff:ffff:ffff:ffff:ffff:ffff
203fc98:ca00::/24fc98:caff:ffff:ffff:ffff:ffff:ffff:ffff
204fc98:cb00::/24fc98:cbff:ffff:ffff:ffff:ffff:ffff:ffff
205fc98:cc00::/24fc98:ccff:ffff:ffff:ffff:ffff:ffff:ffff
206fc98:cd00::/24fc98:cdff:ffff:ffff:ffff:ffff:ffff:ffff
207fc98:ce00::/24fc98:ceff:ffff:ffff:ffff:ffff:ffff:ffff
208fc98:cf00::/24fc98:cfff:ffff:ffff:ffff:ffff:ffff:ffff
209fc98:d000::/24fc98:d0ff:ffff:ffff:ffff:ffff:ffff:ffff
210fc98:d100::/24fc98:d1ff:ffff:ffff:ffff:ffff:ffff:ffff
211fc98:d200::/24fc98:d2ff:ffff:ffff:ffff:ffff:ffff:ffff
212fc98:d300::/24fc98:d3ff:ffff:ffff:ffff:ffff:ffff:ffff
213fc98:d400::/24fc98:d4ff:ffff:ffff:ffff:ffff:ffff:ffff
214fc98:d500::/24fc98:d5ff:ffff:ffff:ffff:ffff:ffff:ffff
215fc98:d600::/24fc98:d6ff:ffff:ffff:ffff:ffff:ffff:ffff
216fc98:d700::/24fc98:d7ff:ffff:ffff:ffff:ffff:ffff:ffff
217fc98:d800::/24fc98:d8ff:ffff:ffff:ffff:ffff:ffff:ffff
218fc98:d900::/24fc98:d9ff:ffff:ffff:ffff:ffff:ffff:ffff
219fc98:da00::/24fc98:daff:ffff:ffff:ffff:ffff:ffff:ffff
220fc98:db00::/24fc98:dbff:ffff:ffff:ffff:ffff:ffff:ffff
221fc98:dc00::/24fc98:dcff:ffff:ffff:ffff:ffff:ffff:ffff
222fc98:dd00::/24fc98:ddff:ffff:ffff:ffff:ffff:ffff:ffff
223fc98:de00::/24fc98:deff:ffff:ffff:ffff:ffff:ffff:ffff
224fc98:df00::/24fc98:dfff:ffff:ffff:ffff:ffff:ffff:ffff
225fc98:e000::/24fc98:e0ff:ffff:ffff:ffff:ffff:ffff:ffff
226fc98:e100::/24fc98:e1ff:ffff:ffff:ffff:ffff:ffff:ffff
227fc98:e200::/24fc98:e2ff:ffff:ffff:ffff:ffff:ffff:ffff
228fc98:e300::/24fc98:e3ff:ffff:ffff:ffff:ffff:ffff:ffff
229fc98:e400::/24fc98:e4ff:ffff:ffff:ffff:ffff:ffff:ffff
230fc98:e500::/24fc98:e5ff:ffff:ffff:ffff:ffff:ffff:ffff
231fc98:e600::/24fc98:e6ff:ffff:ffff:ffff:ffff:ffff:ffff
232fc98:e700::/24fc98:e7ff:ffff:ffff:ffff:ffff:ffff:ffff
233fc98:e800::/24fc98:e8ff:ffff:ffff:ffff:ffff:ffff:ffff
234fc98:e900::/24fc98:e9ff:ffff:ffff:ffff:ffff:ffff:ffff
235fc98:ea00::/24fc98:eaff:ffff:ffff:ffff:ffff:ffff:ffff
236fc98:eb00::/24fc98:ebff:ffff:ffff:ffff:ffff:ffff:ffff
237fc98:ec00::/24fc98:ecff:ffff:ffff:ffff:ffff:ffff:ffff
238fc98:ed00::/24fc98:edff:ffff:ffff:ffff:ffff:ffff:ffff
239fc98:ee00::/24fc98:eeff:ffff:ffff:ffff:ffff:ffff:ffff
240fc98:ef00::/24fc98:efff:ffff:ffff:ffff:ffff:ffff:ffff
241fc98:f000::/24fc98:f0ff:ffff:ffff:ffff:ffff:ffff:ffff
242fc98:f100::/24fc98:f1ff:ffff:ffff:ffff:ffff:ffff:ffff
243fc98:f200::/24fc98:f2ff:ffff:ffff:ffff:ffff:ffff:ffff
244fc98:f300::/24fc98:f3ff:ffff:ffff:ffff:ffff:ffff:ffff
245fc98:f400::/24fc98:f4ff:ffff:ffff:ffff:ffff:ffff:ffff
246fc98:f500::/24fc98:f5ff:ffff:ffff:ffff:ffff:ffff:ffff
247fc98:f600::/24fc98:f6ff:ffff:ffff:ffff:ffff:ffff:ffff
248fc98:f700::/24fc98:f7ff:ffff:ffff:ffff:ffff:ffff:ffff
249fc98:f800::/24fc98:f8ff:ffff:ffff:ffff:ffff:ffff:ffff
250fc98:f900::/24fc98:f9ff:ffff:ffff:ffff:ffff:ffff:ffff
251fc98:fa00::/24fc98:faff:ffff:ffff:ffff:ffff:ffff:ffff
252fc98:fb00::/24fc98:fbff:ffff:ffff:ffff:ffff:ffff:ffff
253fc98:fc00::/24fc98:fcff:ffff:ffff:ffff:ffff:ffff:ffff
254fc98:fd00::/24fc98:fdff:ffff:ffff:ffff:ffff:ffff:ffff
255fc98:fe00::/24fc98:feff:ffff:ffff:ffff:ffff:ffff:ffff
256fc98:ff00::/24fc98: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.