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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
2690::/12
First address
2690::
Last address
269f: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
2690:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.6.2.ip6.arpa
Split into smaller subnets/20
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2690::/12 makes 256 subnets of /20.

Subnets
#SubnetLast address
12690::/202690:fff:ffff:ffff:ffff:ffff:ffff:ffff
22690:1000::/202690:1fff:ffff:ffff:ffff:ffff:ffff:ffff
32690:2000::/202690:2fff:ffff:ffff:ffff:ffff:ffff:ffff
42690:3000::/202690:3fff:ffff:ffff:ffff:ffff:ffff:ffff
52690:4000::/202690:4fff:ffff:ffff:ffff:ffff:ffff:ffff
62690:5000::/202690:5fff:ffff:ffff:ffff:ffff:ffff:ffff
72690:6000::/202690:6fff:ffff:ffff:ffff:ffff:ffff:ffff
82690:7000::/202690:7fff:ffff:ffff:ffff:ffff:ffff:ffff
92690:8000::/202690:8fff:ffff:ffff:ffff:ffff:ffff:ffff
102690:9000::/202690:9fff:ffff:ffff:ffff:ffff:ffff:ffff
112690:a000::/202690:afff:ffff:ffff:ffff:ffff:ffff:ffff
122690:b000::/202690:bfff:ffff:ffff:ffff:ffff:ffff:ffff
132690:c000::/202690:cfff:ffff:ffff:ffff:ffff:ffff:ffff
142690:d000::/202690:dfff:ffff:ffff:ffff:ffff:ffff:ffff
152690:e000::/202690:efff:ffff:ffff:ffff:ffff:ffff:ffff
162690:f000::/202690:ffff:ffff:ffff:ffff:ffff:ffff:ffff
172691::/202691:fff:ffff:ffff:ffff:ffff:ffff:ffff
182691:1000::/202691:1fff:ffff:ffff:ffff:ffff:ffff:ffff
192691:2000::/202691:2fff:ffff:ffff:ffff:ffff:ffff:ffff
202691:3000::/202691:3fff:ffff:ffff:ffff:ffff:ffff:ffff
212691:4000::/202691:4fff:ffff:ffff:ffff:ffff:ffff:ffff
222691:5000::/202691:5fff:ffff:ffff:ffff:ffff:ffff:ffff
232691:6000::/202691:6fff:ffff:ffff:ffff:ffff:ffff:ffff
242691:7000::/202691:7fff:ffff:ffff:ffff:ffff:ffff:ffff
252691:8000::/202691:8fff:ffff:ffff:ffff:ffff:ffff:ffff
262691:9000::/202691:9fff:ffff:ffff:ffff:ffff:ffff:ffff
272691:a000::/202691:afff:ffff:ffff:ffff:ffff:ffff:ffff
282691:b000::/202691:bfff:ffff:ffff:ffff:ffff:ffff:ffff
292691:c000::/202691:cfff:ffff:ffff:ffff:ffff:ffff:ffff
302691:d000::/202691:dfff:ffff:ffff:ffff:ffff:ffff:ffff
312691:e000::/202691:efff:ffff:ffff:ffff:ffff:ffff:ffff
322691:f000::/202691:ffff:ffff:ffff:ffff:ffff:ffff:ffff
332692::/202692:fff:ffff:ffff:ffff:ffff:ffff:ffff
342692:1000::/202692:1fff:ffff:ffff:ffff:ffff:ffff:ffff
352692:2000::/202692:2fff:ffff:ffff:ffff:ffff:ffff:ffff
362692:3000::/202692:3fff:ffff:ffff:ffff:ffff:ffff:ffff
372692:4000::/202692:4fff:ffff:ffff:ffff:ffff:ffff:ffff
382692:5000::/202692:5fff:ffff:ffff:ffff:ffff:ffff:ffff
392692:6000::/202692:6fff:ffff:ffff:ffff:ffff:ffff:ffff
402692:7000::/202692:7fff:ffff:ffff:ffff:ffff:ffff:ffff
412692:8000::/202692:8fff:ffff:ffff:ffff:ffff:ffff:ffff
422692:9000::/202692:9fff:ffff:ffff:ffff:ffff:ffff:ffff
432692:a000::/202692:afff:ffff:ffff:ffff:ffff:ffff:ffff
442692:b000::/202692:bfff:ffff:ffff:ffff:ffff:ffff:ffff
452692:c000::/202692:cfff:ffff:ffff:ffff:ffff:ffff:ffff
462692:d000::/202692:dfff:ffff:ffff:ffff:ffff:ffff:ffff
472692:e000::/202692:efff:ffff:ffff:ffff:ffff:ffff:ffff
482692:f000::/202692:ffff:ffff:ffff:ffff:ffff:ffff:ffff
492693::/202693:fff:ffff:ffff:ffff:ffff:ffff:ffff
502693:1000::/202693:1fff:ffff:ffff:ffff:ffff:ffff:ffff
512693:2000::/202693:2fff:ffff:ffff:ffff:ffff:ffff:ffff
522693:3000::/202693:3fff:ffff:ffff:ffff:ffff:ffff:ffff
532693:4000::/202693:4fff:ffff:ffff:ffff:ffff:ffff:ffff
542693:5000::/202693:5fff:ffff:ffff:ffff:ffff:ffff:ffff
552693:6000::/202693:6fff:ffff:ffff:ffff:ffff:ffff:ffff
562693:7000::/202693:7fff:ffff:ffff:ffff:ffff:ffff:ffff
572693:8000::/202693:8fff:ffff:ffff:ffff:ffff:ffff:ffff
582693:9000::/202693:9fff:ffff:ffff:ffff:ffff:ffff:ffff
592693:a000::/202693:afff:ffff:ffff:ffff:ffff:ffff:ffff
602693:b000::/202693:bfff:ffff:ffff:ffff:ffff:ffff:ffff
612693:c000::/202693:cfff:ffff:ffff:ffff:ffff:ffff:ffff
622693:d000::/202693:dfff:ffff:ffff:ffff:ffff:ffff:ffff
632693:e000::/202693:efff:ffff:ffff:ffff:ffff:ffff:ffff
642693:f000::/202693:ffff:ffff:ffff:ffff:ffff:ffff:ffff
652694::/202694:fff:ffff:ffff:ffff:ffff:ffff:ffff
662694:1000::/202694:1fff:ffff:ffff:ffff:ffff:ffff:ffff
672694:2000::/202694:2fff:ffff:ffff:ffff:ffff:ffff:ffff
682694:3000::/202694:3fff:ffff:ffff:ffff:ffff:ffff:ffff
692694:4000::/202694:4fff:ffff:ffff:ffff:ffff:ffff:ffff
702694:5000::/202694:5fff:ffff:ffff:ffff:ffff:ffff:ffff
712694:6000::/202694:6fff:ffff:ffff:ffff:ffff:ffff:ffff
722694:7000::/202694:7fff:ffff:ffff:ffff:ffff:ffff:ffff
732694:8000::/202694:8fff:ffff:ffff:ffff:ffff:ffff:ffff
742694:9000::/202694:9fff:ffff:ffff:ffff:ffff:ffff:ffff
752694:a000::/202694:afff:ffff:ffff:ffff:ffff:ffff:ffff
762694:b000::/202694:bfff:ffff:ffff:ffff:ffff:ffff:ffff
772694:c000::/202694:cfff:ffff:ffff:ffff:ffff:ffff:ffff
782694:d000::/202694:dfff:ffff:ffff:ffff:ffff:ffff:ffff
792694:e000::/202694:efff:ffff:ffff:ffff:ffff:ffff:ffff
802694:f000::/202694:ffff:ffff:ffff:ffff:ffff:ffff:ffff
812695::/202695:fff:ffff:ffff:ffff:ffff:ffff:ffff
822695:1000::/202695:1fff:ffff:ffff:ffff:ffff:ffff:ffff
832695:2000::/202695:2fff:ffff:ffff:ffff:ffff:ffff:ffff
842695:3000::/202695:3fff:ffff:ffff:ffff:ffff:ffff:ffff
852695:4000::/202695:4fff:ffff:ffff:ffff:ffff:ffff:ffff
862695:5000::/202695:5fff:ffff:ffff:ffff:ffff:ffff:ffff
872695:6000::/202695:6fff:ffff:ffff:ffff:ffff:ffff:ffff
882695:7000::/202695:7fff:ffff:ffff:ffff:ffff:ffff:ffff
892695:8000::/202695:8fff:ffff:ffff:ffff:ffff:ffff:ffff
902695:9000::/202695:9fff:ffff:ffff:ffff:ffff:ffff:ffff
912695:a000::/202695:afff:ffff:ffff:ffff:ffff:ffff:ffff
922695:b000::/202695:bfff:ffff:ffff:ffff:ffff:ffff:ffff
932695:c000::/202695:cfff:ffff:ffff:ffff:ffff:ffff:ffff
942695:d000::/202695:dfff:ffff:ffff:ffff:ffff:ffff:ffff
952695:e000::/202695:efff:ffff:ffff:ffff:ffff:ffff:ffff
962695:f000::/202695:ffff:ffff:ffff:ffff:ffff:ffff:ffff
972696::/202696:fff:ffff:ffff:ffff:ffff:ffff:ffff
982696:1000::/202696:1fff:ffff:ffff:ffff:ffff:ffff:ffff
992696:2000::/202696:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1002696:3000::/202696:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1012696:4000::/202696:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1022696:5000::/202696:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1032696:6000::/202696:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1042696:7000::/202696:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1052696:8000::/202696:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1062696:9000::/202696:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1072696:a000::/202696:afff:ffff:ffff:ffff:ffff:ffff:ffff
1082696:b000::/202696:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1092696:c000::/202696:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1102696:d000::/202696:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1112696:e000::/202696:efff:ffff:ffff:ffff:ffff:ffff:ffff
1122696:f000::/202696:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1132697::/202697:fff:ffff:ffff:ffff:ffff:ffff:ffff
1142697:1000::/202697:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1152697:2000::/202697:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1162697:3000::/202697:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1172697:4000::/202697:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1182697:5000::/202697:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1192697:6000::/202697:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1202697:7000::/202697:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1212697:8000::/202697:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1222697:9000::/202697:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1232697:a000::/202697:afff:ffff:ffff:ffff:ffff:ffff:ffff
1242697:b000::/202697:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1252697:c000::/202697:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1262697:d000::/202697:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1272697:e000::/202697:efff:ffff:ffff:ffff:ffff:ffff:ffff
1282697:f000::/202697:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1292698::/202698:fff:ffff:ffff:ffff:ffff:ffff:ffff
1302698:1000::/202698:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1312698:2000::/202698:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1322698:3000::/202698:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1332698:4000::/202698:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1342698:5000::/202698:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1352698:6000::/202698:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1362698:7000::/202698:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1372698:8000::/202698:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1382698:9000::/202698:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1392698:a000::/202698:afff:ffff:ffff:ffff:ffff:ffff:ffff
1402698:b000::/202698:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1412698:c000::/202698:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1422698:d000::/202698:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1432698:e000::/202698:efff:ffff:ffff:ffff:ffff:ffff:ffff
1442698:f000::/202698:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1452699::/202699:fff:ffff:ffff:ffff:ffff:ffff:ffff
1462699:1000::/202699:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1472699:2000::/202699:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1482699:3000::/202699:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1492699:4000::/202699:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1502699:5000::/202699:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1512699:6000::/202699:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1522699:7000::/202699:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1532699:8000::/202699:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1542699:9000::/202699:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1552699:a000::/202699:afff:ffff:ffff:ffff:ffff:ffff:ffff
1562699:b000::/202699:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1572699:c000::/202699:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1582699:d000::/202699:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1592699:e000::/202699:efff:ffff:ffff:ffff:ffff:ffff:ffff
1602699:f000::/202699:ffff:ffff:ffff:ffff:ffff:ffff:ffff
161269a::/20269a:fff:ffff:ffff:ffff:ffff:ffff:ffff
162269a:1000::/20269a:1fff:ffff:ffff:ffff:ffff:ffff:ffff
163269a:2000::/20269a:2fff:ffff:ffff:ffff:ffff:ffff:ffff
164269a:3000::/20269a:3fff:ffff:ffff:ffff:ffff:ffff:ffff
165269a:4000::/20269a:4fff:ffff:ffff:ffff:ffff:ffff:ffff
166269a:5000::/20269a:5fff:ffff:ffff:ffff:ffff:ffff:ffff
167269a:6000::/20269a:6fff:ffff:ffff:ffff:ffff:ffff:ffff
168269a:7000::/20269a:7fff:ffff:ffff:ffff:ffff:ffff:ffff
169269a:8000::/20269a:8fff:ffff:ffff:ffff:ffff:ffff:ffff
170269a:9000::/20269a:9fff:ffff:ffff:ffff:ffff:ffff:ffff
171269a:a000::/20269a:afff:ffff:ffff:ffff:ffff:ffff:ffff
172269a:b000::/20269a:bfff:ffff:ffff:ffff:ffff:ffff:ffff
173269a:c000::/20269a:cfff:ffff:ffff:ffff:ffff:ffff:ffff
174269a:d000::/20269a:dfff:ffff:ffff:ffff:ffff:ffff:ffff
175269a:e000::/20269a:efff:ffff:ffff:ffff:ffff:ffff:ffff
176269a:f000::/20269a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
177269b::/20269b:fff:ffff:ffff:ffff:ffff:ffff:ffff
178269b:1000::/20269b:1fff:ffff:ffff:ffff:ffff:ffff:ffff
179269b:2000::/20269b:2fff:ffff:ffff:ffff:ffff:ffff:ffff
180269b:3000::/20269b:3fff:ffff:ffff:ffff:ffff:ffff:ffff
181269b:4000::/20269b:4fff:ffff:ffff:ffff:ffff:ffff:ffff
182269b:5000::/20269b:5fff:ffff:ffff:ffff:ffff:ffff:ffff
183269b:6000::/20269b:6fff:ffff:ffff:ffff:ffff:ffff:ffff
184269b:7000::/20269b:7fff:ffff:ffff:ffff:ffff:ffff:ffff
185269b:8000::/20269b:8fff:ffff:ffff:ffff:ffff:ffff:ffff
186269b:9000::/20269b:9fff:ffff:ffff:ffff:ffff:ffff:ffff
187269b:a000::/20269b:afff:ffff:ffff:ffff:ffff:ffff:ffff
188269b:b000::/20269b:bfff:ffff:ffff:ffff:ffff:ffff:ffff
189269b:c000::/20269b:cfff:ffff:ffff:ffff:ffff:ffff:ffff
190269b:d000::/20269b:dfff:ffff:ffff:ffff:ffff:ffff:ffff
191269b:e000::/20269b:efff:ffff:ffff:ffff:ffff:ffff:ffff
192269b:f000::/20269b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
193269c::/20269c:fff:ffff:ffff:ffff:ffff:ffff:ffff
194269c:1000::/20269c:1fff:ffff:ffff:ffff:ffff:ffff:ffff
195269c:2000::/20269c:2fff:ffff:ffff:ffff:ffff:ffff:ffff
196269c:3000::/20269c:3fff:ffff:ffff:ffff:ffff:ffff:ffff
197269c:4000::/20269c:4fff:ffff:ffff:ffff:ffff:ffff:ffff
198269c:5000::/20269c:5fff:ffff:ffff:ffff:ffff:ffff:ffff
199269c:6000::/20269c:6fff:ffff:ffff:ffff:ffff:ffff:ffff
200269c:7000::/20269c:7fff:ffff:ffff:ffff:ffff:ffff:ffff
201269c:8000::/20269c:8fff:ffff:ffff:ffff:ffff:ffff:ffff
202269c:9000::/20269c:9fff:ffff:ffff:ffff:ffff:ffff:ffff
203269c:a000::/20269c:afff:ffff:ffff:ffff:ffff:ffff:ffff
204269c:b000::/20269c:bfff:ffff:ffff:ffff:ffff:ffff:ffff
205269c:c000::/20269c:cfff:ffff:ffff:ffff:ffff:ffff:ffff
206269c:d000::/20269c:dfff:ffff:ffff:ffff:ffff:ffff:ffff
207269c:e000::/20269c:efff:ffff:ffff:ffff:ffff:ffff:ffff
208269c:f000::/20269c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
209269d::/20269d:fff:ffff:ffff:ffff:ffff:ffff:ffff
210269d:1000::/20269d:1fff:ffff:ffff:ffff:ffff:ffff:ffff
211269d:2000::/20269d:2fff:ffff:ffff:ffff:ffff:ffff:ffff
212269d:3000::/20269d:3fff:ffff:ffff:ffff:ffff:ffff:ffff
213269d:4000::/20269d:4fff:ffff:ffff:ffff:ffff:ffff:ffff
214269d:5000::/20269d:5fff:ffff:ffff:ffff:ffff:ffff:ffff
215269d:6000::/20269d:6fff:ffff:ffff:ffff:ffff:ffff:ffff
216269d:7000::/20269d:7fff:ffff:ffff:ffff:ffff:ffff:ffff
217269d:8000::/20269d:8fff:ffff:ffff:ffff:ffff:ffff:ffff
218269d:9000::/20269d:9fff:ffff:ffff:ffff:ffff:ffff:ffff
219269d:a000::/20269d:afff:ffff:ffff:ffff:ffff:ffff:ffff
220269d:b000::/20269d:bfff:ffff:ffff:ffff:ffff:ffff:ffff
221269d:c000::/20269d:cfff:ffff:ffff:ffff:ffff:ffff:ffff
222269d:d000::/20269d:dfff:ffff:ffff:ffff:ffff:ffff:ffff
223269d:e000::/20269d:efff:ffff:ffff:ffff:ffff:ffff:ffff
224269d:f000::/20269d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
225269e::/20269e:fff:ffff:ffff:ffff:ffff:ffff:ffff
226269e:1000::/20269e:1fff:ffff:ffff:ffff:ffff:ffff:ffff
227269e:2000::/20269e:2fff:ffff:ffff:ffff:ffff:ffff:ffff
228269e:3000::/20269e:3fff:ffff:ffff:ffff:ffff:ffff:ffff
229269e:4000::/20269e:4fff:ffff:ffff:ffff:ffff:ffff:ffff
230269e:5000::/20269e:5fff:ffff:ffff:ffff:ffff:ffff:ffff
231269e:6000::/20269e:6fff:ffff:ffff:ffff:ffff:ffff:ffff
232269e:7000::/20269e:7fff:ffff:ffff:ffff:ffff:ffff:ffff
233269e:8000::/20269e:8fff:ffff:ffff:ffff:ffff:ffff:ffff
234269e:9000::/20269e:9fff:ffff:ffff:ffff:ffff:ffff:ffff
235269e:a000::/20269e:afff:ffff:ffff:ffff:ffff:ffff:ffff
236269e:b000::/20269e:bfff:ffff:ffff:ffff:ffff:ffff:ffff
237269e:c000::/20269e:cfff:ffff:ffff:ffff:ffff:ffff:ffff
238269e:d000::/20269e:dfff:ffff:ffff:ffff:ffff:ffff:ffff
239269e:e000::/20269e:efff:ffff:ffff:ffff:ffff:ffff:ffff
240269e:f000::/20269e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
241269f::/20269f:fff:ffff:ffff:ffff:ffff:ffff:ffff
242269f:1000::/20269f:1fff:ffff:ffff:ffff:ffff:ffff:ffff
243269f:2000::/20269f:2fff:ffff:ffff:ffff:ffff:ffff:ffff
244269f:3000::/20269f:3fff:ffff:ffff:ffff:ffff:ffff:ffff
245269f:4000::/20269f:4fff:ffff:ffff:ffff:ffff:ffff:ffff
246269f:5000::/20269f:5fff:ffff:ffff:ffff:ffff:ffff:ffff
247269f:6000::/20269f:6fff:ffff:ffff:ffff:ffff:ffff:ffff
248269f:7000::/20269f:7fff:ffff:ffff:ffff:ffff:ffff:ffff
249269f:8000::/20269f:8fff:ffff:ffff:ffff:ffff:ffff:ffff
250269f:9000::/20269f:9fff:ffff:ffff:ffff:ffff:ffff:ffff
251269f:a000::/20269f:afff:ffff:ffff:ffff:ffff:ffff:ffff
252269f:b000::/20269f:bfff:ffff:ffff:ffff:ffff:ffff:ffff
253269f:c000::/20269f:cfff:ffff:ffff:ffff:ffff:ffff:ffff
254269f:d000::/20269f:dfff:ffff:ffff:ffff:ffff:ffff:ffff
255269f:e000::/20269f:efff:ffff:ffff:ffff:ffff:ffff:ffff
256269f:f000::/20269f: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.