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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/12
Addresses2^116
/64 networks2^52
Network
2670::/12
First address
2670::
Last address
267f:ffff:ffff:ffff:ffff:ffff:ffff:ffff
Addresses
83,076,749,736,557,242,056,487,941,267,521,536 (2^116)
/64 networks (LANs)
4,503,599,627,370,496 (2^52)
Full form
2670:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
7.6.2.ip6.arpa
Split into smaller subnets/20
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2670::/12 makes 256 subnets of /20.

Subnets
#SubnetLast address
12670::/202670:fff:ffff:ffff:ffff:ffff:ffff:ffff
22670:1000::/202670:1fff:ffff:ffff:ffff:ffff:ffff:ffff
32670:2000::/202670:2fff:ffff:ffff:ffff:ffff:ffff:ffff
42670:3000::/202670:3fff:ffff:ffff:ffff:ffff:ffff:ffff
52670:4000::/202670:4fff:ffff:ffff:ffff:ffff:ffff:ffff
62670:5000::/202670:5fff:ffff:ffff:ffff:ffff:ffff:ffff
72670:6000::/202670:6fff:ffff:ffff:ffff:ffff:ffff:ffff
82670:7000::/202670:7fff:ffff:ffff:ffff:ffff:ffff:ffff
92670:8000::/202670:8fff:ffff:ffff:ffff:ffff:ffff:ffff
102670:9000::/202670:9fff:ffff:ffff:ffff:ffff:ffff:ffff
112670:a000::/202670:afff:ffff:ffff:ffff:ffff:ffff:ffff
122670:b000::/202670:bfff:ffff:ffff:ffff:ffff:ffff:ffff
132670:c000::/202670:cfff:ffff:ffff:ffff:ffff:ffff:ffff
142670:d000::/202670:dfff:ffff:ffff:ffff:ffff:ffff:ffff
152670:e000::/202670:efff:ffff:ffff:ffff:ffff:ffff:ffff
162670:f000::/202670:ffff:ffff:ffff:ffff:ffff:ffff:ffff
172671::/202671:fff:ffff:ffff:ffff:ffff:ffff:ffff
182671:1000::/202671:1fff:ffff:ffff:ffff:ffff:ffff:ffff
192671:2000::/202671:2fff:ffff:ffff:ffff:ffff:ffff:ffff
202671:3000::/202671:3fff:ffff:ffff:ffff:ffff:ffff:ffff
212671:4000::/202671:4fff:ffff:ffff:ffff:ffff:ffff:ffff
222671:5000::/202671:5fff:ffff:ffff:ffff:ffff:ffff:ffff
232671:6000::/202671:6fff:ffff:ffff:ffff:ffff:ffff:ffff
242671:7000::/202671:7fff:ffff:ffff:ffff:ffff:ffff:ffff
252671:8000::/202671:8fff:ffff:ffff:ffff:ffff:ffff:ffff
262671:9000::/202671:9fff:ffff:ffff:ffff:ffff:ffff:ffff
272671:a000::/202671:afff:ffff:ffff:ffff:ffff:ffff:ffff
282671:b000::/202671:bfff:ffff:ffff:ffff:ffff:ffff:ffff
292671:c000::/202671:cfff:ffff:ffff:ffff:ffff:ffff:ffff
302671:d000::/202671:dfff:ffff:ffff:ffff:ffff:ffff:ffff
312671:e000::/202671:efff:ffff:ffff:ffff:ffff:ffff:ffff
322671:f000::/202671:ffff:ffff:ffff:ffff:ffff:ffff:ffff
332672::/202672:fff:ffff:ffff:ffff:ffff:ffff:ffff
342672:1000::/202672:1fff:ffff:ffff:ffff:ffff:ffff:ffff
352672:2000::/202672:2fff:ffff:ffff:ffff:ffff:ffff:ffff
362672:3000::/202672:3fff:ffff:ffff:ffff:ffff:ffff:ffff
372672:4000::/202672:4fff:ffff:ffff:ffff:ffff:ffff:ffff
382672:5000::/202672:5fff:ffff:ffff:ffff:ffff:ffff:ffff
392672:6000::/202672:6fff:ffff:ffff:ffff:ffff:ffff:ffff
402672:7000::/202672:7fff:ffff:ffff:ffff:ffff:ffff:ffff
412672:8000::/202672:8fff:ffff:ffff:ffff:ffff:ffff:ffff
422672:9000::/202672:9fff:ffff:ffff:ffff:ffff:ffff:ffff
432672:a000::/202672:afff:ffff:ffff:ffff:ffff:ffff:ffff
442672:b000::/202672:bfff:ffff:ffff:ffff:ffff:ffff:ffff
452672:c000::/202672:cfff:ffff:ffff:ffff:ffff:ffff:ffff
462672:d000::/202672:dfff:ffff:ffff:ffff:ffff:ffff:ffff
472672:e000::/202672:efff:ffff:ffff:ffff:ffff:ffff:ffff
482672:f000::/202672:ffff:ffff:ffff:ffff:ffff:ffff:ffff
492673::/202673:fff:ffff:ffff:ffff:ffff:ffff:ffff
502673:1000::/202673:1fff:ffff:ffff:ffff:ffff:ffff:ffff
512673:2000::/202673:2fff:ffff:ffff:ffff:ffff:ffff:ffff
522673:3000::/202673:3fff:ffff:ffff:ffff:ffff:ffff:ffff
532673:4000::/202673:4fff:ffff:ffff:ffff:ffff:ffff:ffff
542673:5000::/202673:5fff:ffff:ffff:ffff:ffff:ffff:ffff
552673:6000::/202673:6fff:ffff:ffff:ffff:ffff:ffff:ffff
562673:7000::/202673:7fff:ffff:ffff:ffff:ffff:ffff:ffff
572673:8000::/202673:8fff:ffff:ffff:ffff:ffff:ffff:ffff
582673:9000::/202673:9fff:ffff:ffff:ffff:ffff:ffff:ffff
592673:a000::/202673:afff:ffff:ffff:ffff:ffff:ffff:ffff
602673:b000::/202673:bfff:ffff:ffff:ffff:ffff:ffff:ffff
612673:c000::/202673:cfff:ffff:ffff:ffff:ffff:ffff:ffff
622673:d000::/202673:dfff:ffff:ffff:ffff:ffff:ffff:ffff
632673:e000::/202673:efff:ffff:ffff:ffff:ffff:ffff:ffff
642673:f000::/202673:ffff:ffff:ffff:ffff:ffff:ffff:ffff
652674::/202674:fff:ffff:ffff:ffff:ffff:ffff:ffff
662674:1000::/202674:1fff:ffff:ffff:ffff:ffff:ffff:ffff
672674:2000::/202674:2fff:ffff:ffff:ffff:ffff:ffff:ffff
682674:3000::/202674:3fff:ffff:ffff:ffff:ffff:ffff:ffff
692674:4000::/202674:4fff:ffff:ffff:ffff:ffff:ffff:ffff
702674:5000::/202674:5fff:ffff:ffff:ffff:ffff:ffff:ffff
712674:6000::/202674:6fff:ffff:ffff:ffff:ffff:ffff:ffff
722674:7000::/202674:7fff:ffff:ffff:ffff:ffff:ffff:ffff
732674:8000::/202674:8fff:ffff:ffff:ffff:ffff:ffff:ffff
742674:9000::/202674:9fff:ffff:ffff:ffff:ffff:ffff:ffff
752674:a000::/202674:afff:ffff:ffff:ffff:ffff:ffff:ffff
762674:b000::/202674:bfff:ffff:ffff:ffff:ffff:ffff:ffff
772674:c000::/202674:cfff:ffff:ffff:ffff:ffff:ffff:ffff
782674:d000::/202674:dfff:ffff:ffff:ffff:ffff:ffff:ffff
792674:e000::/202674:efff:ffff:ffff:ffff:ffff:ffff:ffff
802674:f000::/202674:ffff:ffff:ffff:ffff:ffff:ffff:ffff
812675::/202675:fff:ffff:ffff:ffff:ffff:ffff:ffff
822675:1000::/202675:1fff:ffff:ffff:ffff:ffff:ffff:ffff
832675:2000::/202675:2fff:ffff:ffff:ffff:ffff:ffff:ffff
842675:3000::/202675:3fff:ffff:ffff:ffff:ffff:ffff:ffff
852675:4000::/202675:4fff:ffff:ffff:ffff:ffff:ffff:ffff
862675:5000::/202675:5fff:ffff:ffff:ffff:ffff:ffff:ffff
872675:6000::/202675:6fff:ffff:ffff:ffff:ffff:ffff:ffff
882675:7000::/202675:7fff:ffff:ffff:ffff:ffff:ffff:ffff
892675:8000::/202675:8fff:ffff:ffff:ffff:ffff:ffff:ffff
902675:9000::/202675:9fff:ffff:ffff:ffff:ffff:ffff:ffff
912675:a000::/202675:afff:ffff:ffff:ffff:ffff:ffff:ffff
922675:b000::/202675:bfff:ffff:ffff:ffff:ffff:ffff:ffff
932675:c000::/202675:cfff:ffff:ffff:ffff:ffff:ffff:ffff
942675:d000::/202675:dfff:ffff:ffff:ffff:ffff:ffff:ffff
952675:e000::/202675:efff:ffff:ffff:ffff:ffff:ffff:ffff
962675:f000::/202675:ffff:ffff:ffff:ffff:ffff:ffff:ffff
972676::/202676:fff:ffff:ffff:ffff:ffff:ffff:ffff
982676:1000::/202676:1fff:ffff:ffff:ffff:ffff:ffff:ffff
992676:2000::/202676:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1002676:3000::/202676:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1012676:4000::/202676:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1022676:5000::/202676:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1032676:6000::/202676:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1042676:7000::/202676:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1052676:8000::/202676:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1062676:9000::/202676:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1072676:a000::/202676:afff:ffff:ffff:ffff:ffff:ffff:ffff
1082676:b000::/202676:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1092676:c000::/202676:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1102676:d000::/202676:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1112676:e000::/202676:efff:ffff:ffff:ffff:ffff:ffff:ffff
1122676:f000::/202676:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1132677::/202677:fff:ffff:ffff:ffff:ffff:ffff:ffff
1142677:1000::/202677:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1152677:2000::/202677:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1162677:3000::/202677:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1172677:4000::/202677:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1182677:5000::/202677:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1192677:6000::/202677:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1202677:7000::/202677:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1212677:8000::/202677:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1222677:9000::/202677:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1232677:a000::/202677:afff:ffff:ffff:ffff:ffff:ffff:ffff
1242677:b000::/202677:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1252677:c000::/202677:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1262677:d000::/202677:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1272677:e000::/202677:efff:ffff:ffff:ffff:ffff:ffff:ffff
1282677:f000::/202677:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1292678::/202678:fff:ffff:ffff:ffff:ffff:ffff:ffff
1302678:1000::/202678:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1312678:2000::/202678:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1322678:3000::/202678:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1332678:4000::/202678:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1342678:5000::/202678:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1352678:6000::/202678:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1362678:7000::/202678:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1372678:8000::/202678:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1382678:9000::/202678:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1392678:a000::/202678:afff:ffff:ffff:ffff:ffff:ffff:ffff
1402678:b000::/202678:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1412678:c000::/202678:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1422678:d000::/202678:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1432678:e000::/202678:efff:ffff:ffff:ffff:ffff:ffff:ffff
1442678:f000::/202678:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1452679::/202679:fff:ffff:ffff:ffff:ffff:ffff:ffff
1462679:1000::/202679:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1472679:2000::/202679:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1482679:3000::/202679:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1492679:4000::/202679:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1502679:5000::/202679:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1512679:6000::/202679:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1522679:7000::/202679:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1532679:8000::/202679:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1542679:9000::/202679:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1552679:a000::/202679:afff:ffff:ffff:ffff:ffff:ffff:ffff
1562679:b000::/202679:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1572679:c000::/202679:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1582679:d000::/202679:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1592679:e000::/202679:efff:ffff:ffff:ffff:ffff:ffff:ffff
1602679:f000::/202679:ffff:ffff:ffff:ffff:ffff:ffff:ffff
161267a::/20267a:fff:ffff:ffff:ffff:ffff:ffff:ffff
162267a:1000::/20267a:1fff:ffff:ffff:ffff:ffff:ffff:ffff
163267a:2000::/20267a:2fff:ffff:ffff:ffff:ffff:ffff:ffff
164267a:3000::/20267a:3fff:ffff:ffff:ffff:ffff:ffff:ffff
165267a:4000::/20267a:4fff:ffff:ffff:ffff:ffff:ffff:ffff
166267a:5000::/20267a:5fff:ffff:ffff:ffff:ffff:ffff:ffff
167267a:6000::/20267a:6fff:ffff:ffff:ffff:ffff:ffff:ffff
168267a:7000::/20267a:7fff:ffff:ffff:ffff:ffff:ffff:ffff
169267a:8000::/20267a:8fff:ffff:ffff:ffff:ffff:ffff:ffff
170267a:9000::/20267a:9fff:ffff:ffff:ffff:ffff:ffff:ffff
171267a:a000::/20267a:afff:ffff:ffff:ffff:ffff:ffff:ffff
172267a:b000::/20267a:bfff:ffff:ffff:ffff:ffff:ffff:ffff
173267a:c000::/20267a:cfff:ffff:ffff:ffff:ffff:ffff:ffff
174267a:d000::/20267a:dfff:ffff:ffff:ffff:ffff:ffff:ffff
175267a:e000::/20267a:efff:ffff:ffff:ffff:ffff:ffff:ffff
176267a:f000::/20267a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
177267b::/20267b:fff:ffff:ffff:ffff:ffff:ffff:ffff
178267b:1000::/20267b:1fff:ffff:ffff:ffff:ffff:ffff:ffff
179267b:2000::/20267b:2fff:ffff:ffff:ffff:ffff:ffff:ffff
180267b:3000::/20267b:3fff:ffff:ffff:ffff:ffff:ffff:ffff
181267b:4000::/20267b:4fff:ffff:ffff:ffff:ffff:ffff:ffff
182267b:5000::/20267b:5fff:ffff:ffff:ffff:ffff:ffff:ffff
183267b:6000::/20267b:6fff:ffff:ffff:ffff:ffff:ffff:ffff
184267b:7000::/20267b:7fff:ffff:ffff:ffff:ffff:ffff:ffff
185267b:8000::/20267b:8fff:ffff:ffff:ffff:ffff:ffff:ffff
186267b:9000::/20267b:9fff:ffff:ffff:ffff:ffff:ffff:ffff
187267b:a000::/20267b:afff:ffff:ffff:ffff:ffff:ffff:ffff
188267b:b000::/20267b:bfff:ffff:ffff:ffff:ffff:ffff:ffff
189267b:c000::/20267b:cfff:ffff:ffff:ffff:ffff:ffff:ffff
190267b:d000::/20267b:dfff:ffff:ffff:ffff:ffff:ffff:ffff
191267b:e000::/20267b:efff:ffff:ffff:ffff:ffff:ffff:ffff
192267b:f000::/20267b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
193267c::/20267c:fff:ffff:ffff:ffff:ffff:ffff:ffff
194267c:1000::/20267c:1fff:ffff:ffff:ffff:ffff:ffff:ffff
195267c:2000::/20267c:2fff:ffff:ffff:ffff:ffff:ffff:ffff
196267c:3000::/20267c:3fff:ffff:ffff:ffff:ffff:ffff:ffff
197267c:4000::/20267c:4fff:ffff:ffff:ffff:ffff:ffff:ffff
198267c:5000::/20267c:5fff:ffff:ffff:ffff:ffff:ffff:ffff
199267c:6000::/20267c:6fff:ffff:ffff:ffff:ffff:ffff:ffff
200267c:7000::/20267c:7fff:ffff:ffff:ffff:ffff:ffff:ffff
201267c:8000::/20267c:8fff:ffff:ffff:ffff:ffff:ffff:ffff
202267c:9000::/20267c:9fff:ffff:ffff:ffff:ffff:ffff:ffff
203267c:a000::/20267c:afff:ffff:ffff:ffff:ffff:ffff:ffff
204267c:b000::/20267c:bfff:ffff:ffff:ffff:ffff:ffff:ffff
205267c:c000::/20267c:cfff:ffff:ffff:ffff:ffff:ffff:ffff
206267c:d000::/20267c:dfff:ffff:ffff:ffff:ffff:ffff:ffff
207267c:e000::/20267c:efff:ffff:ffff:ffff:ffff:ffff:ffff
208267c:f000::/20267c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
209267d::/20267d:fff:ffff:ffff:ffff:ffff:ffff:ffff
210267d:1000::/20267d:1fff:ffff:ffff:ffff:ffff:ffff:ffff
211267d:2000::/20267d:2fff:ffff:ffff:ffff:ffff:ffff:ffff
212267d:3000::/20267d:3fff:ffff:ffff:ffff:ffff:ffff:ffff
213267d:4000::/20267d:4fff:ffff:ffff:ffff:ffff:ffff:ffff
214267d:5000::/20267d:5fff:ffff:ffff:ffff:ffff:ffff:ffff
215267d:6000::/20267d:6fff:ffff:ffff:ffff:ffff:ffff:ffff
216267d:7000::/20267d:7fff:ffff:ffff:ffff:ffff:ffff:ffff
217267d:8000::/20267d:8fff:ffff:ffff:ffff:ffff:ffff:ffff
218267d:9000::/20267d:9fff:ffff:ffff:ffff:ffff:ffff:ffff
219267d:a000::/20267d:afff:ffff:ffff:ffff:ffff:ffff:ffff
220267d:b000::/20267d:bfff:ffff:ffff:ffff:ffff:ffff:ffff
221267d:c000::/20267d:cfff:ffff:ffff:ffff:ffff:ffff:ffff
222267d:d000::/20267d:dfff:ffff:ffff:ffff:ffff:ffff:ffff
223267d:e000::/20267d:efff:ffff:ffff:ffff:ffff:ffff:ffff
224267d:f000::/20267d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
225267e::/20267e:fff:ffff:ffff:ffff:ffff:ffff:ffff
226267e:1000::/20267e:1fff:ffff:ffff:ffff:ffff:ffff:ffff
227267e:2000::/20267e:2fff:ffff:ffff:ffff:ffff:ffff:ffff
228267e:3000::/20267e:3fff:ffff:ffff:ffff:ffff:ffff:ffff
229267e:4000::/20267e:4fff:ffff:ffff:ffff:ffff:ffff:ffff
230267e:5000::/20267e:5fff:ffff:ffff:ffff:ffff:ffff:ffff
231267e:6000::/20267e:6fff:ffff:ffff:ffff:ffff:ffff:ffff
232267e:7000::/20267e:7fff:ffff:ffff:ffff:ffff:ffff:ffff
233267e:8000::/20267e:8fff:ffff:ffff:ffff:ffff:ffff:ffff
234267e:9000::/20267e:9fff:ffff:ffff:ffff:ffff:ffff:ffff
235267e:a000::/20267e:afff:ffff:ffff:ffff:ffff:ffff:ffff
236267e:b000::/20267e:bfff:ffff:ffff:ffff:ffff:ffff:ffff
237267e:c000::/20267e:cfff:ffff:ffff:ffff:ffff:ffff:ffff
238267e:d000::/20267e:dfff:ffff:ffff:ffff:ffff:ffff:ffff
239267e:e000::/20267e:efff:ffff:ffff:ffff:ffff:ffff:ffff
240267e:f000::/20267e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
241267f::/20267f:fff:ffff:ffff:ffff:ffff:ffff:ffff
242267f:1000::/20267f:1fff:ffff:ffff:ffff:ffff:ffff:ffff
243267f:2000::/20267f:2fff:ffff:ffff:ffff:ffff:ffff:ffff
244267f:3000::/20267f:3fff:ffff:ffff:ffff:ffff:ffff:ffff
245267f:4000::/20267f:4fff:ffff:ffff:ffff:ffff:ffff:ffff
246267f:5000::/20267f:5fff:ffff:ffff:ffff:ffff:ffff:ffff
247267f:6000::/20267f:6fff:ffff:ffff:ffff:ffff:ffff:ffff
248267f:7000::/20267f:7fff:ffff:ffff:ffff:ffff:ffff:ffff
249267f:8000::/20267f:8fff:ffff:ffff:ffff:ffff:ffff:ffff
250267f:9000::/20267f:9fff:ffff:ffff:ffff:ffff:ffff:ffff
251267f:a000::/20267f:afff:ffff:ffff:ffff:ffff:ffff:ffff
252267f:b000::/20267f:bfff:ffff:ffff:ffff:ffff:ffff:ffff
253267f:c000::/20267f:cfff:ffff:ffff:ffff:ffff:ffff:ffff
254267f:d000::/20267f:dfff:ffff:ffff:ffff:ffff:ffff:ffff
255267f:e000::/20267f:efff:ffff:ffff:ffff:ffff:ffff:ffff
256267f:f000::/20267f: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.