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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/24
Addresses2^104
/64 networks2^40
Network
ff79:ec00::/24
First address
ff79:ec00::
Last address
ff79:ecff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
20,282,409,603,651,670,423,947,251,286,016 (2^104)
/64 networks (LANs)
1,099,511,627,776 (2^40)
Full form
ff79:ec00:0000:0000:0000:0000:0000:0000
Type
Multicast ff00::/8
One-to-many traffic; replaces broadcast
Reverse DNS zone
c.e.9.7.f.f.ip6.arpa
Split into smaller subnets/32
/25 (2)/26 (4)/27 (8)/28 (16)/32 (256)/36 (4,096)/40 (65,536)

ff79:ec00::/24 makes 256 subnets of /32.

Subnets
#SubnetLast address
1ff79:ec00::/32ff79:ec00:ffff:ffff:ffff:ffff:ffff:ffff
2ff79:ec01::/32ff79:ec01:ffff:ffff:ffff:ffff:ffff:ffff
3ff79:ec02::/32ff79:ec02:ffff:ffff:ffff:ffff:ffff:ffff
4ff79:ec03::/32ff79:ec03:ffff:ffff:ffff:ffff:ffff:ffff
5ff79:ec04::/32ff79:ec04:ffff:ffff:ffff:ffff:ffff:ffff
6ff79:ec05::/32ff79:ec05:ffff:ffff:ffff:ffff:ffff:ffff
7ff79:ec06::/32ff79:ec06:ffff:ffff:ffff:ffff:ffff:ffff
8ff79:ec07::/32ff79:ec07:ffff:ffff:ffff:ffff:ffff:ffff
9ff79:ec08::/32ff79:ec08:ffff:ffff:ffff:ffff:ffff:ffff
10ff79:ec09::/32ff79:ec09:ffff:ffff:ffff:ffff:ffff:ffff
11ff79:ec0a::/32ff79:ec0a:ffff:ffff:ffff:ffff:ffff:ffff
12ff79:ec0b::/32ff79:ec0b:ffff:ffff:ffff:ffff:ffff:ffff
13ff79:ec0c::/32ff79:ec0c:ffff:ffff:ffff:ffff:ffff:ffff
14ff79:ec0d::/32ff79:ec0d:ffff:ffff:ffff:ffff:ffff:ffff
15ff79:ec0e::/32ff79:ec0e:ffff:ffff:ffff:ffff:ffff:ffff
16ff79:ec0f::/32ff79:ec0f:ffff:ffff:ffff:ffff:ffff:ffff
17ff79:ec10::/32ff79:ec10:ffff:ffff:ffff:ffff:ffff:ffff
18ff79:ec11::/32ff79:ec11:ffff:ffff:ffff:ffff:ffff:ffff
19ff79:ec12::/32ff79:ec12:ffff:ffff:ffff:ffff:ffff:ffff
20ff79:ec13::/32ff79:ec13:ffff:ffff:ffff:ffff:ffff:ffff
21ff79:ec14::/32ff79:ec14:ffff:ffff:ffff:ffff:ffff:ffff
22ff79:ec15::/32ff79:ec15:ffff:ffff:ffff:ffff:ffff:ffff
23ff79:ec16::/32ff79:ec16:ffff:ffff:ffff:ffff:ffff:ffff
24ff79:ec17::/32ff79:ec17:ffff:ffff:ffff:ffff:ffff:ffff
25ff79:ec18::/32ff79:ec18:ffff:ffff:ffff:ffff:ffff:ffff
26ff79:ec19::/32ff79:ec19:ffff:ffff:ffff:ffff:ffff:ffff
27ff79:ec1a::/32ff79:ec1a:ffff:ffff:ffff:ffff:ffff:ffff
28ff79:ec1b::/32ff79:ec1b:ffff:ffff:ffff:ffff:ffff:ffff
29ff79:ec1c::/32ff79:ec1c:ffff:ffff:ffff:ffff:ffff:ffff
30ff79:ec1d::/32ff79:ec1d:ffff:ffff:ffff:ffff:ffff:ffff
31ff79:ec1e::/32ff79:ec1e:ffff:ffff:ffff:ffff:ffff:ffff
32ff79:ec1f::/32ff79:ec1f:ffff:ffff:ffff:ffff:ffff:ffff
33ff79:ec20::/32ff79:ec20:ffff:ffff:ffff:ffff:ffff:ffff
34ff79:ec21::/32ff79:ec21:ffff:ffff:ffff:ffff:ffff:ffff
35ff79:ec22::/32ff79:ec22:ffff:ffff:ffff:ffff:ffff:ffff
36ff79:ec23::/32ff79:ec23:ffff:ffff:ffff:ffff:ffff:ffff
37ff79:ec24::/32ff79:ec24:ffff:ffff:ffff:ffff:ffff:ffff
38ff79:ec25::/32ff79:ec25:ffff:ffff:ffff:ffff:ffff:ffff
39ff79:ec26::/32ff79:ec26:ffff:ffff:ffff:ffff:ffff:ffff
40ff79:ec27::/32ff79:ec27:ffff:ffff:ffff:ffff:ffff:ffff
41ff79:ec28::/32ff79:ec28:ffff:ffff:ffff:ffff:ffff:ffff
42ff79:ec29::/32ff79:ec29:ffff:ffff:ffff:ffff:ffff:ffff
43ff79:ec2a::/32ff79:ec2a:ffff:ffff:ffff:ffff:ffff:ffff
44ff79:ec2b::/32ff79:ec2b:ffff:ffff:ffff:ffff:ffff:ffff
45ff79:ec2c::/32ff79:ec2c:ffff:ffff:ffff:ffff:ffff:ffff
46ff79:ec2d::/32ff79:ec2d:ffff:ffff:ffff:ffff:ffff:ffff
47ff79:ec2e::/32ff79:ec2e:ffff:ffff:ffff:ffff:ffff:ffff
48ff79:ec2f::/32ff79:ec2f:ffff:ffff:ffff:ffff:ffff:ffff
49ff79:ec30::/32ff79:ec30:ffff:ffff:ffff:ffff:ffff:ffff
50ff79:ec31::/32ff79:ec31:ffff:ffff:ffff:ffff:ffff:ffff
51ff79:ec32::/32ff79:ec32:ffff:ffff:ffff:ffff:ffff:ffff
52ff79:ec33::/32ff79:ec33:ffff:ffff:ffff:ffff:ffff:ffff
53ff79:ec34::/32ff79:ec34:ffff:ffff:ffff:ffff:ffff:ffff
54ff79:ec35::/32ff79:ec35:ffff:ffff:ffff:ffff:ffff:ffff
55ff79:ec36::/32ff79:ec36:ffff:ffff:ffff:ffff:ffff:ffff
56ff79:ec37::/32ff79:ec37:ffff:ffff:ffff:ffff:ffff:ffff
57ff79:ec38::/32ff79:ec38:ffff:ffff:ffff:ffff:ffff:ffff
58ff79:ec39::/32ff79:ec39:ffff:ffff:ffff:ffff:ffff:ffff
59ff79:ec3a::/32ff79:ec3a:ffff:ffff:ffff:ffff:ffff:ffff
60ff79:ec3b::/32ff79:ec3b:ffff:ffff:ffff:ffff:ffff:ffff
61ff79:ec3c::/32ff79:ec3c:ffff:ffff:ffff:ffff:ffff:ffff
62ff79:ec3d::/32ff79:ec3d:ffff:ffff:ffff:ffff:ffff:ffff
63ff79:ec3e::/32ff79:ec3e:ffff:ffff:ffff:ffff:ffff:ffff
64ff79:ec3f::/32ff79:ec3f:ffff:ffff:ffff:ffff:ffff:ffff
65ff79:ec40::/32ff79:ec40:ffff:ffff:ffff:ffff:ffff:ffff
66ff79:ec41::/32ff79:ec41:ffff:ffff:ffff:ffff:ffff:ffff
67ff79:ec42::/32ff79:ec42:ffff:ffff:ffff:ffff:ffff:ffff
68ff79:ec43::/32ff79:ec43:ffff:ffff:ffff:ffff:ffff:ffff
69ff79:ec44::/32ff79:ec44:ffff:ffff:ffff:ffff:ffff:ffff
70ff79:ec45::/32ff79:ec45:ffff:ffff:ffff:ffff:ffff:ffff
71ff79:ec46::/32ff79:ec46:ffff:ffff:ffff:ffff:ffff:ffff
72ff79:ec47::/32ff79:ec47:ffff:ffff:ffff:ffff:ffff:ffff
73ff79:ec48::/32ff79:ec48:ffff:ffff:ffff:ffff:ffff:ffff
74ff79:ec49::/32ff79:ec49:ffff:ffff:ffff:ffff:ffff:ffff
75ff79:ec4a::/32ff79:ec4a:ffff:ffff:ffff:ffff:ffff:ffff
76ff79:ec4b::/32ff79:ec4b:ffff:ffff:ffff:ffff:ffff:ffff
77ff79:ec4c::/32ff79:ec4c:ffff:ffff:ffff:ffff:ffff:ffff
78ff79:ec4d::/32ff79:ec4d:ffff:ffff:ffff:ffff:ffff:ffff
79ff79:ec4e::/32ff79:ec4e:ffff:ffff:ffff:ffff:ffff:ffff
80ff79:ec4f::/32ff79:ec4f:ffff:ffff:ffff:ffff:ffff:ffff
81ff79:ec50::/32ff79:ec50:ffff:ffff:ffff:ffff:ffff:ffff
82ff79:ec51::/32ff79:ec51:ffff:ffff:ffff:ffff:ffff:ffff
83ff79:ec52::/32ff79:ec52:ffff:ffff:ffff:ffff:ffff:ffff
84ff79:ec53::/32ff79:ec53:ffff:ffff:ffff:ffff:ffff:ffff
85ff79:ec54::/32ff79:ec54:ffff:ffff:ffff:ffff:ffff:ffff
86ff79:ec55::/32ff79:ec55:ffff:ffff:ffff:ffff:ffff:ffff
87ff79:ec56::/32ff79:ec56:ffff:ffff:ffff:ffff:ffff:ffff
88ff79:ec57::/32ff79:ec57:ffff:ffff:ffff:ffff:ffff:ffff
89ff79:ec58::/32ff79:ec58:ffff:ffff:ffff:ffff:ffff:ffff
90ff79:ec59::/32ff79:ec59:ffff:ffff:ffff:ffff:ffff:ffff
91ff79:ec5a::/32ff79:ec5a:ffff:ffff:ffff:ffff:ffff:ffff
92ff79:ec5b::/32ff79:ec5b:ffff:ffff:ffff:ffff:ffff:ffff
93ff79:ec5c::/32ff79:ec5c:ffff:ffff:ffff:ffff:ffff:ffff
94ff79:ec5d::/32ff79:ec5d:ffff:ffff:ffff:ffff:ffff:ffff
95ff79:ec5e::/32ff79:ec5e:ffff:ffff:ffff:ffff:ffff:ffff
96ff79:ec5f::/32ff79:ec5f:ffff:ffff:ffff:ffff:ffff:ffff
97ff79:ec60::/32ff79:ec60:ffff:ffff:ffff:ffff:ffff:ffff
98ff79:ec61::/32ff79:ec61:ffff:ffff:ffff:ffff:ffff:ffff
99ff79:ec62::/32ff79:ec62:ffff:ffff:ffff:ffff:ffff:ffff
100ff79:ec63::/32ff79:ec63:ffff:ffff:ffff:ffff:ffff:ffff
101ff79:ec64::/32ff79:ec64:ffff:ffff:ffff:ffff:ffff:ffff
102ff79:ec65::/32ff79:ec65:ffff:ffff:ffff:ffff:ffff:ffff
103ff79:ec66::/32ff79:ec66:ffff:ffff:ffff:ffff:ffff:ffff
104ff79:ec67::/32ff79:ec67:ffff:ffff:ffff:ffff:ffff:ffff
105ff79:ec68::/32ff79:ec68:ffff:ffff:ffff:ffff:ffff:ffff
106ff79:ec69::/32ff79:ec69:ffff:ffff:ffff:ffff:ffff:ffff
107ff79:ec6a::/32ff79:ec6a:ffff:ffff:ffff:ffff:ffff:ffff
108ff79:ec6b::/32ff79:ec6b:ffff:ffff:ffff:ffff:ffff:ffff
109ff79:ec6c::/32ff79:ec6c:ffff:ffff:ffff:ffff:ffff:ffff
110ff79:ec6d::/32ff79:ec6d:ffff:ffff:ffff:ffff:ffff:ffff
111ff79:ec6e::/32ff79:ec6e:ffff:ffff:ffff:ffff:ffff:ffff
112ff79:ec6f::/32ff79:ec6f:ffff:ffff:ffff:ffff:ffff:ffff
113ff79:ec70::/32ff79:ec70:ffff:ffff:ffff:ffff:ffff:ffff
114ff79:ec71::/32ff79:ec71:ffff:ffff:ffff:ffff:ffff:ffff
115ff79:ec72::/32ff79:ec72:ffff:ffff:ffff:ffff:ffff:ffff
116ff79:ec73::/32ff79:ec73:ffff:ffff:ffff:ffff:ffff:ffff
117ff79:ec74::/32ff79:ec74:ffff:ffff:ffff:ffff:ffff:ffff
118ff79:ec75::/32ff79:ec75:ffff:ffff:ffff:ffff:ffff:ffff
119ff79:ec76::/32ff79:ec76:ffff:ffff:ffff:ffff:ffff:ffff
120ff79:ec77::/32ff79:ec77:ffff:ffff:ffff:ffff:ffff:ffff
121ff79:ec78::/32ff79:ec78:ffff:ffff:ffff:ffff:ffff:ffff
122ff79:ec79::/32ff79:ec79:ffff:ffff:ffff:ffff:ffff:ffff
123ff79:ec7a::/32ff79:ec7a:ffff:ffff:ffff:ffff:ffff:ffff
124ff79:ec7b::/32ff79:ec7b:ffff:ffff:ffff:ffff:ffff:ffff
125ff79:ec7c::/32ff79:ec7c:ffff:ffff:ffff:ffff:ffff:ffff
126ff79:ec7d::/32ff79:ec7d:ffff:ffff:ffff:ffff:ffff:ffff
127ff79:ec7e::/32ff79:ec7e:ffff:ffff:ffff:ffff:ffff:ffff
128ff79:ec7f::/32ff79:ec7f:ffff:ffff:ffff:ffff:ffff:ffff
129ff79:ec80::/32ff79:ec80:ffff:ffff:ffff:ffff:ffff:ffff
130ff79:ec81::/32ff79:ec81:ffff:ffff:ffff:ffff:ffff:ffff
131ff79:ec82::/32ff79:ec82:ffff:ffff:ffff:ffff:ffff:ffff
132ff79:ec83::/32ff79:ec83:ffff:ffff:ffff:ffff:ffff:ffff
133ff79:ec84::/32ff79:ec84:ffff:ffff:ffff:ffff:ffff:ffff
134ff79:ec85::/32ff79:ec85:ffff:ffff:ffff:ffff:ffff:ffff
135ff79:ec86::/32ff79:ec86:ffff:ffff:ffff:ffff:ffff:ffff
136ff79:ec87::/32ff79:ec87:ffff:ffff:ffff:ffff:ffff:ffff
137ff79:ec88::/32ff79:ec88:ffff:ffff:ffff:ffff:ffff:ffff
138ff79:ec89::/32ff79:ec89:ffff:ffff:ffff:ffff:ffff:ffff
139ff79:ec8a::/32ff79:ec8a:ffff:ffff:ffff:ffff:ffff:ffff
140ff79:ec8b::/32ff79:ec8b:ffff:ffff:ffff:ffff:ffff:ffff
141ff79:ec8c::/32ff79:ec8c:ffff:ffff:ffff:ffff:ffff:ffff
142ff79:ec8d::/32ff79:ec8d:ffff:ffff:ffff:ffff:ffff:ffff
143ff79:ec8e::/32ff79:ec8e:ffff:ffff:ffff:ffff:ffff:ffff
144ff79:ec8f::/32ff79:ec8f:ffff:ffff:ffff:ffff:ffff:ffff
145ff79:ec90::/32ff79:ec90:ffff:ffff:ffff:ffff:ffff:ffff
146ff79:ec91::/32ff79:ec91:ffff:ffff:ffff:ffff:ffff:ffff
147ff79:ec92::/32ff79:ec92:ffff:ffff:ffff:ffff:ffff:ffff
148ff79:ec93::/32ff79:ec93:ffff:ffff:ffff:ffff:ffff:ffff
149ff79:ec94::/32ff79:ec94:ffff:ffff:ffff:ffff:ffff:ffff
150ff79:ec95::/32ff79:ec95:ffff:ffff:ffff:ffff:ffff:ffff
151ff79:ec96::/32ff79:ec96:ffff:ffff:ffff:ffff:ffff:ffff
152ff79:ec97::/32ff79:ec97:ffff:ffff:ffff:ffff:ffff:ffff
153ff79:ec98::/32ff79:ec98:ffff:ffff:ffff:ffff:ffff:ffff
154ff79:ec99::/32ff79:ec99:ffff:ffff:ffff:ffff:ffff:ffff
155ff79:ec9a::/32ff79:ec9a:ffff:ffff:ffff:ffff:ffff:ffff
156ff79:ec9b::/32ff79:ec9b:ffff:ffff:ffff:ffff:ffff:ffff
157ff79:ec9c::/32ff79:ec9c:ffff:ffff:ffff:ffff:ffff:ffff
158ff79:ec9d::/32ff79:ec9d:ffff:ffff:ffff:ffff:ffff:ffff
159ff79:ec9e::/32ff79:ec9e:ffff:ffff:ffff:ffff:ffff:ffff
160ff79:ec9f::/32ff79:ec9f:ffff:ffff:ffff:ffff:ffff:ffff
161ff79:eca0::/32ff79:eca0:ffff:ffff:ffff:ffff:ffff:ffff
162ff79:eca1::/32ff79:eca1:ffff:ffff:ffff:ffff:ffff:ffff
163ff79:eca2::/32ff79:eca2:ffff:ffff:ffff:ffff:ffff:ffff
164ff79:eca3::/32ff79:eca3:ffff:ffff:ffff:ffff:ffff:ffff
165ff79:eca4::/32ff79:eca4:ffff:ffff:ffff:ffff:ffff:ffff
166ff79:eca5::/32ff79:eca5:ffff:ffff:ffff:ffff:ffff:ffff
167ff79:eca6::/32ff79:eca6:ffff:ffff:ffff:ffff:ffff:ffff
168ff79:eca7::/32ff79:eca7:ffff:ffff:ffff:ffff:ffff:ffff
169ff79:eca8::/32ff79:eca8:ffff:ffff:ffff:ffff:ffff:ffff
170ff79:eca9::/32ff79:eca9:ffff:ffff:ffff:ffff:ffff:ffff
171ff79:ecaa::/32ff79:ecaa:ffff:ffff:ffff:ffff:ffff:ffff
172ff79:ecab::/32ff79:ecab:ffff:ffff:ffff:ffff:ffff:ffff
173ff79:ecac::/32ff79:ecac:ffff:ffff:ffff:ffff:ffff:ffff
174ff79:ecad::/32ff79:ecad:ffff:ffff:ffff:ffff:ffff:ffff
175ff79:ecae::/32ff79:ecae:ffff:ffff:ffff:ffff:ffff:ffff
176ff79:ecaf::/32ff79:ecaf:ffff:ffff:ffff:ffff:ffff:ffff
177ff79:ecb0::/32ff79:ecb0:ffff:ffff:ffff:ffff:ffff:ffff
178ff79:ecb1::/32ff79:ecb1:ffff:ffff:ffff:ffff:ffff:ffff
179ff79:ecb2::/32ff79:ecb2:ffff:ffff:ffff:ffff:ffff:ffff
180ff79:ecb3::/32ff79:ecb3:ffff:ffff:ffff:ffff:ffff:ffff
181ff79:ecb4::/32ff79:ecb4:ffff:ffff:ffff:ffff:ffff:ffff
182ff79:ecb5::/32ff79:ecb5:ffff:ffff:ffff:ffff:ffff:ffff
183ff79:ecb6::/32ff79:ecb6:ffff:ffff:ffff:ffff:ffff:ffff
184ff79:ecb7::/32ff79:ecb7:ffff:ffff:ffff:ffff:ffff:ffff
185ff79:ecb8::/32ff79:ecb8:ffff:ffff:ffff:ffff:ffff:ffff
186ff79:ecb9::/32ff79:ecb9:ffff:ffff:ffff:ffff:ffff:ffff
187ff79:ecba::/32ff79:ecba:ffff:ffff:ffff:ffff:ffff:ffff
188ff79:ecbb::/32ff79:ecbb:ffff:ffff:ffff:ffff:ffff:ffff
189ff79:ecbc::/32ff79:ecbc:ffff:ffff:ffff:ffff:ffff:ffff
190ff79:ecbd::/32ff79:ecbd:ffff:ffff:ffff:ffff:ffff:ffff
191ff79:ecbe::/32ff79:ecbe:ffff:ffff:ffff:ffff:ffff:ffff
192ff79:ecbf::/32ff79:ecbf:ffff:ffff:ffff:ffff:ffff:ffff
193ff79:ecc0::/32ff79:ecc0:ffff:ffff:ffff:ffff:ffff:ffff
194ff79:ecc1::/32ff79:ecc1:ffff:ffff:ffff:ffff:ffff:ffff
195ff79:ecc2::/32ff79:ecc2:ffff:ffff:ffff:ffff:ffff:ffff
196ff79:ecc3::/32ff79:ecc3:ffff:ffff:ffff:ffff:ffff:ffff
197ff79:ecc4::/32ff79:ecc4:ffff:ffff:ffff:ffff:ffff:ffff
198ff79:ecc5::/32ff79:ecc5:ffff:ffff:ffff:ffff:ffff:ffff
199ff79:ecc6::/32ff79:ecc6:ffff:ffff:ffff:ffff:ffff:ffff
200ff79:ecc7::/32ff79:ecc7:ffff:ffff:ffff:ffff:ffff:ffff
201ff79:ecc8::/32ff79:ecc8:ffff:ffff:ffff:ffff:ffff:ffff
202ff79:ecc9::/32ff79:ecc9:ffff:ffff:ffff:ffff:ffff:ffff
203ff79:ecca::/32ff79:ecca:ffff:ffff:ffff:ffff:ffff:ffff
204ff79:eccb::/32ff79:eccb:ffff:ffff:ffff:ffff:ffff:ffff
205ff79:eccc::/32ff79:eccc:ffff:ffff:ffff:ffff:ffff:ffff
206ff79:eccd::/32ff79:eccd:ffff:ffff:ffff:ffff:ffff:ffff
207ff79:ecce::/32ff79:ecce:ffff:ffff:ffff:ffff:ffff:ffff
208ff79:eccf::/32ff79:eccf:ffff:ffff:ffff:ffff:ffff:ffff
209ff79:ecd0::/32ff79:ecd0:ffff:ffff:ffff:ffff:ffff:ffff
210ff79:ecd1::/32ff79:ecd1:ffff:ffff:ffff:ffff:ffff:ffff
211ff79:ecd2::/32ff79:ecd2:ffff:ffff:ffff:ffff:ffff:ffff
212ff79:ecd3::/32ff79:ecd3:ffff:ffff:ffff:ffff:ffff:ffff
213ff79:ecd4::/32ff79:ecd4:ffff:ffff:ffff:ffff:ffff:ffff
214ff79:ecd5::/32ff79:ecd5:ffff:ffff:ffff:ffff:ffff:ffff
215ff79:ecd6::/32ff79:ecd6:ffff:ffff:ffff:ffff:ffff:ffff
216ff79:ecd7::/32ff79:ecd7:ffff:ffff:ffff:ffff:ffff:ffff
217ff79:ecd8::/32ff79:ecd8:ffff:ffff:ffff:ffff:ffff:ffff
218ff79:ecd9::/32ff79:ecd9:ffff:ffff:ffff:ffff:ffff:ffff
219ff79:ecda::/32ff79:ecda:ffff:ffff:ffff:ffff:ffff:ffff
220ff79:ecdb::/32ff79:ecdb:ffff:ffff:ffff:ffff:ffff:ffff
221ff79:ecdc::/32ff79:ecdc:ffff:ffff:ffff:ffff:ffff:ffff
222ff79:ecdd::/32ff79:ecdd:ffff:ffff:ffff:ffff:ffff:ffff
223ff79:ecde::/32ff79:ecde:ffff:ffff:ffff:ffff:ffff:ffff
224ff79:ecdf::/32ff79:ecdf:ffff:ffff:ffff:ffff:ffff:ffff
225ff79:ece0::/32ff79:ece0:ffff:ffff:ffff:ffff:ffff:ffff
226ff79:ece1::/32ff79:ece1:ffff:ffff:ffff:ffff:ffff:ffff
227ff79:ece2::/32ff79:ece2:ffff:ffff:ffff:ffff:ffff:ffff
228ff79:ece3::/32ff79:ece3:ffff:ffff:ffff:ffff:ffff:ffff
229ff79:ece4::/32ff79:ece4:ffff:ffff:ffff:ffff:ffff:ffff
230ff79:ece5::/32ff79:ece5:ffff:ffff:ffff:ffff:ffff:ffff
231ff79:ece6::/32ff79:ece6:ffff:ffff:ffff:ffff:ffff:ffff
232ff79:ece7::/32ff79:ece7:ffff:ffff:ffff:ffff:ffff:ffff
233ff79:ece8::/32ff79:ece8:ffff:ffff:ffff:ffff:ffff:ffff
234ff79:ece9::/32ff79:ece9:ffff:ffff:ffff:ffff:ffff:ffff
235ff79:ecea::/32ff79:ecea:ffff:ffff:ffff:ffff:ffff:ffff
236ff79:eceb::/32ff79:eceb:ffff:ffff:ffff:ffff:ffff:ffff
237ff79:ecec::/32ff79:ecec:ffff:ffff:ffff:ffff:ffff:ffff
238ff79:eced::/32ff79:eced:ffff:ffff:ffff:ffff:ffff:ffff
239ff79:ecee::/32ff79:ecee:ffff:ffff:ffff:ffff:ffff:ffff
240ff79:ecef::/32ff79:ecef:ffff:ffff:ffff:ffff:ffff:ffff
241ff79:ecf0::/32ff79:ecf0:ffff:ffff:ffff:ffff:ffff:ffff
242ff79:ecf1::/32ff79:ecf1:ffff:ffff:ffff:ffff:ffff:ffff
243ff79:ecf2::/32ff79:ecf2:ffff:ffff:ffff:ffff:ffff:ffff
244ff79:ecf3::/32ff79:ecf3:ffff:ffff:ffff:ffff:ffff:ffff
245ff79:ecf4::/32ff79:ecf4:ffff:ffff:ffff:ffff:ffff:ffff
246ff79:ecf5::/32ff79:ecf5:ffff:ffff:ffff:ffff:ffff:ffff
247ff79:ecf6::/32ff79:ecf6:ffff:ffff:ffff:ffff:ffff:ffff
248ff79:ecf7::/32ff79:ecf7:ffff:ffff:ffff:ffff:ffff:ffff
249ff79:ecf8::/32ff79:ecf8:ffff:ffff:ffff:ffff:ffff:ffff
250ff79:ecf9::/32ff79:ecf9:ffff:ffff:ffff:ffff:ffff:ffff
251ff79:ecfa::/32ff79:ecfa:ffff:ffff:ffff:ffff:ffff:ffff
252ff79:ecfb::/32ff79:ecfb:ffff:ffff:ffff:ffff:ffff:ffff
253ff79:ecfc::/32ff79:ecfc:ffff:ffff:ffff:ffff:ffff:ffff
254ff79:ecfd::/32ff79:ecfd:ffff:ffff:ffff:ffff:ffff:ffff
255ff79:ecfe::/32ff79:ecfe:ffff:ffff:ffff:ffff:ffff:ffff
256ff79:ecff::/32ff79:ecff: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.