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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
2310::/12
First address
2310::
Last address
231f: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
2310:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
1.3.2.ip6.arpa
Split into smaller subnets/20
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2310::/12 makes 256 subnets of /20.

Subnets
#SubnetLast address
12310::/202310:fff:ffff:ffff:ffff:ffff:ffff:ffff
22310:1000::/202310:1fff:ffff:ffff:ffff:ffff:ffff:ffff
32310:2000::/202310:2fff:ffff:ffff:ffff:ffff:ffff:ffff
42310:3000::/202310:3fff:ffff:ffff:ffff:ffff:ffff:ffff
52310:4000::/202310:4fff:ffff:ffff:ffff:ffff:ffff:ffff
62310:5000::/202310:5fff:ffff:ffff:ffff:ffff:ffff:ffff
72310:6000::/202310:6fff:ffff:ffff:ffff:ffff:ffff:ffff
82310:7000::/202310:7fff:ffff:ffff:ffff:ffff:ffff:ffff
92310:8000::/202310:8fff:ffff:ffff:ffff:ffff:ffff:ffff
102310:9000::/202310:9fff:ffff:ffff:ffff:ffff:ffff:ffff
112310:a000::/202310:afff:ffff:ffff:ffff:ffff:ffff:ffff
122310:b000::/202310:bfff:ffff:ffff:ffff:ffff:ffff:ffff
132310:c000::/202310:cfff:ffff:ffff:ffff:ffff:ffff:ffff
142310:d000::/202310:dfff:ffff:ffff:ffff:ffff:ffff:ffff
152310:e000::/202310:efff:ffff:ffff:ffff:ffff:ffff:ffff
162310:f000::/202310:ffff:ffff:ffff:ffff:ffff:ffff:ffff
172311::/202311:fff:ffff:ffff:ffff:ffff:ffff:ffff
182311:1000::/202311:1fff:ffff:ffff:ffff:ffff:ffff:ffff
192311:2000::/202311:2fff:ffff:ffff:ffff:ffff:ffff:ffff
202311:3000::/202311:3fff:ffff:ffff:ffff:ffff:ffff:ffff
212311:4000::/202311:4fff:ffff:ffff:ffff:ffff:ffff:ffff
222311:5000::/202311:5fff:ffff:ffff:ffff:ffff:ffff:ffff
232311:6000::/202311:6fff:ffff:ffff:ffff:ffff:ffff:ffff
242311:7000::/202311:7fff:ffff:ffff:ffff:ffff:ffff:ffff
252311:8000::/202311:8fff:ffff:ffff:ffff:ffff:ffff:ffff
262311:9000::/202311:9fff:ffff:ffff:ffff:ffff:ffff:ffff
272311:a000::/202311:afff:ffff:ffff:ffff:ffff:ffff:ffff
282311:b000::/202311:bfff:ffff:ffff:ffff:ffff:ffff:ffff
292311:c000::/202311:cfff:ffff:ffff:ffff:ffff:ffff:ffff
302311:d000::/202311:dfff:ffff:ffff:ffff:ffff:ffff:ffff
312311:e000::/202311:efff:ffff:ffff:ffff:ffff:ffff:ffff
322311:f000::/202311:ffff:ffff:ffff:ffff:ffff:ffff:ffff
332312::/202312:fff:ffff:ffff:ffff:ffff:ffff:ffff
342312:1000::/202312:1fff:ffff:ffff:ffff:ffff:ffff:ffff
352312:2000::/202312:2fff:ffff:ffff:ffff:ffff:ffff:ffff
362312:3000::/202312:3fff:ffff:ffff:ffff:ffff:ffff:ffff
372312:4000::/202312:4fff:ffff:ffff:ffff:ffff:ffff:ffff
382312:5000::/202312:5fff:ffff:ffff:ffff:ffff:ffff:ffff
392312:6000::/202312:6fff:ffff:ffff:ffff:ffff:ffff:ffff
402312:7000::/202312:7fff:ffff:ffff:ffff:ffff:ffff:ffff
412312:8000::/202312:8fff:ffff:ffff:ffff:ffff:ffff:ffff
422312:9000::/202312:9fff:ffff:ffff:ffff:ffff:ffff:ffff
432312:a000::/202312:afff:ffff:ffff:ffff:ffff:ffff:ffff
442312:b000::/202312:bfff:ffff:ffff:ffff:ffff:ffff:ffff
452312:c000::/202312:cfff:ffff:ffff:ffff:ffff:ffff:ffff
462312:d000::/202312:dfff:ffff:ffff:ffff:ffff:ffff:ffff
472312:e000::/202312:efff:ffff:ffff:ffff:ffff:ffff:ffff
482312:f000::/202312:ffff:ffff:ffff:ffff:ffff:ffff:ffff
492313::/202313:fff:ffff:ffff:ffff:ffff:ffff:ffff
502313:1000::/202313:1fff:ffff:ffff:ffff:ffff:ffff:ffff
512313:2000::/202313:2fff:ffff:ffff:ffff:ffff:ffff:ffff
522313:3000::/202313:3fff:ffff:ffff:ffff:ffff:ffff:ffff
532313:4000::/202313:4fff:ffff:ffff:ffff:ffff:ffff:ffff
542313:5000::/202313:5fff:ffff:ffff:ffff:ffff:ffff:ffff
552313:6000::/202313:6fff:ffff:ffff:ffff:ffff:ffff:ffff
562313:7000::/202313:7fff:ffff:ffff:ffff:ffff:ffff:ffff
572313:8000::/202313:8fff:ffff:ffff:ffff:ffff:ffff:ffff
582313:9000::/202313:9fff:ffff:ffff:ffff:ffff:ffff:ffff
592313:a000::/202313:afff:ffff:ffff:ffff:ffff:ffff:ffff
602313:b000::/202313:bfff:ffff:ffff:ffff:ffff:ffff:ffff
612313:c000::/202313:cfff:ffff:ffff:ffff:ffff:ffff:ffff
622313:d000::/202313:dfff:ffff:ffff:ffff:ffff:ffff:ffff
632313:e000::/202313:efff:ffff:ffff:ffff:ffff:ffff:ffff
642313:f000::/202313:ffff:ffff:ffff:ffff:ffff:ffff:ffff
652314::/202314:fff:ffff:ffff:ffff:ffff:ffff:ffff
662314:1000::/202314:1fff:ffff:ffff:ffff:ffff:ffff:ffff
672314:2000::/202314:2fff:ffff:ffff:ffff:ffff:ffff:ffff
682314:3000::/202314:3fff:ffff:ffff:ffff:ffff:ffff:ffff
692314:4000::/202314:4fff:ffff:ffff:ffff:ffff:ffff:ffff
702314:5000::/202314:5fff:ffff:ffff:ffff:ffff:ffff:ffff
712314:6000::/202314:6fff:ffff:ffff:ffff:ffff:ffff:ffff
722314:7000::/202314:7fff:ffff:ffff:ffff:ffff:ffff:ffff
732314:8000::/202314:8fff:ffff:ffff:ffff:ffff:ffff:ffff
742314:9000::/202314:9fff:ffff:ffff:ffff:ffff:ffff:ffff
752314:a000::/202314:afff:ffff:ffff:ffff:ffff:ffff:ffff
762314:b000::/202314:bfff:ffff:ffff:ffff:ffff:ffff:ffff
772314:c000::/202314:cfff:ffff:ffff:ffff:ffff:ffff:ffff
782314:d000::/202314:dfff:ffff:ffff:ffff:ffff:ffff:ffff
792314:e000::/202314:efff:ffff:ffff:ffff:ffff:ffff:ffff
802314:f000::/202314:ffff:ffff:ffff:ffff:ffff:ffff:ffff
812315::/202315:fff:ffff:ffff:ffff:ffff:ffff:ffff
822315:1000::/202315:1fff:ffff:ffff:ffff:ffff:ffff:ffff
832315:2000::/202315:2fff:ffff:ffff:ffff:ffff:ffff:ffff
842315:3000::/202315:3fff:ffff:ffff:ffff:ffff:ffff:ffff
852315:4000::/202315:4fff:ffff:ffff:ffff:ffff:ffff:ffff
862315:5000::/202315:5fff:ffff:ffff:ffff:ffff:ffff:ffff
872315:6000::/202315:6fff:ffff:ffff:ffff:ffff:ffff:ffff
882315:7000::/202315:7fff:ffff:ffff:ffff:ffff:ffff:ffff
892315:8000::/202315:8fff:ffff:ffff:ffff:ffff:ffff:ffff
902315:9000::/202315:9fff:ffff:ffff:ffff:ffff:ffff:ffff
912315:a000::/202315:afff:ffff:ffff:ffff:ffff:ffff:ffff
922315:b000::/202315:bfff:ffff:ffff:ffff:ffff:ffff:ffff
932315:c000::/202315:cfff:ffff:ffff:ffff:ffff:ffff:ffff
942315:d000::/202315:dfff:ffff:ffff:ffff:ffff:ffff:ffff
952315:e000::/202315:efff:ffff:ffff:ffff:ffff:ffff:ffff
962315:f000::/202315:ffff:ffff:ffff:ffff:ffff:ffff:ffff
972316::/202316:fff:ffff:ffff:ffff:ffff:ffff:ffff
982316:1000::/202316:1fff:ffff:ffff:ffff:ffff:ffff:ffff
992316:2000::/202316:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1002316:3000::/202316:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1012316:4000::/202316:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1022316:5000::/202316:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1032316:6000::/202316:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1042316:7000::/202316:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1052316:8000::/202316:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1062316:9000::/202316:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1072316:a000::/202316:afff:ffff:ffff:ffff:ffff:ffff:ffff
1082316:b000::/202316:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1092316:c000::/202316:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1102316:d000::/202316:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1112316:e000::/202316:efff:ffff:ffff:ffff:ffff:ffff:ffff
1122316:f000::/202316:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1132317::/202317:fff:ffff:ffff:ffff:ffff:ffff:ffff
1142317:1000::/202317:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1152317:2000::/202317:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1162317:3000::/202317:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1172317:4000::/202317:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1182317:5000::/202317:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1192317:6000::/202317:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1202317:7000::/202317:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1212317:8000::/202317:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1222317:9000::/202317:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1232317:a000::/202317:afff:ffff:ffff:ffff:ffff:ffff:ffff
1242317:b000::/202317:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1252317:c000::/202317:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1262317:d000::/202317:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1272317:e000::/202317:efff:ffff:ffff:ffff:ffff:ffff:ffff
1282317:f000::/202317:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1292318::/202318:fff:ffff:ffff:ffff:ffff:ffff:ffff
1302318:1000::/202318:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1312318:2000::/202318:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1322318:3000::/202318:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1332318:4000::/202318:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1342318:5000::/202318:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1352318:6000::/202318:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1362318:7000::/202318:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1372318:8000::/202318:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1382318:9000::/202318:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1392318:a000::/202318:afff:ffff:ffff:ffff:ffff:ffff:ffff
1402318:b000::/202318:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1412318:c000::/202318:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1422318:d000::/202318:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1432318:e000::/202318:efff:ffff:ffff:ffff:ffff:ffff:ffff
1442318:f000::/202318:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1452319::/202319:fff:ffff:ffff:ffff:ffff:ffff:ffff
1462319:1000::/202319:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1472319:2000::/202319:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1482319:3000::/202319:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1492319:4000::/202319:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1502319:5000::/202319:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1512319:6000::/202319:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1522319:7000::/202319:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1532319:8000::/202319:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1542319:9000::/202319:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1552319:a000::/202319:afff:ffff:ffff:ffff:ffff:ffff:ffff
1562319:b000::/202319:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1572319:c000::/202319:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1582319:d000::/202319:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1592319:e000::/202319:efff:ffff:ffff:ffff:ffff:ffff:ffff
1602319:f000::/202319:ffff:ffff:ffff:ffff:ffff:ffff:ffff
161231a::/20231a:fff:ffff:ffff:ffff:ffff:ffff:ffff
162231a:1000::/20231a:1fff:ffff:ffff:ffff:ffff:ffff:ffff
163231a:2000::/20231a:2fff:ffff:ffff:ffff:ffff:ffff:ffff
164231a:3000::/20231a:3fff:ffff:ffff:ffff:ffff:ffff:ffff
165231a:4000::/20231a:4fff:ffff:ffff:ffff:ffff:ffff:ffff
166231a:5000::/20231a:5fff:ffff:ffff:ffff:ffff:ffff:ffff
167231a:6000::/20231a:6fff:ffff:ffff:ffff:ffff:ffff:ffff
168231a:7000::/20231a:7fff:ffff:ffff:ffff:ffff:ffff:ffff
169231a:8000::/20231a:8fff:ffff:ffff:ffff:ffff:ffff:ffff
170231a:9000::/20231a:9fff:ffff:ffff:ffff:ffff:ffff:ffff
171231a:a000::/20231a:afff:ffff:ffff:ffff:ffff:ffff:ffff
172231a:b000::/20231a:bfff:ffff:ffff:ffff:ffff:ffff:ffff
173231a:c000::/20231a:cfff:ffff:ffff:ffff:ffff:ffff:ffff
174231a:d000::/20231a:dfff:ffff:ffff:ffff:ffff:ffff:ffff
175231a:e000::/20231a:efff:ffff:ffff:ffff:ffff:ffff:ffff
176231a:f000::/20231a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
177231b::/20231b:fff:ffff:ffff:ffff:ffff:ffff:ffff
178231b:1000::/20231b:1fff:ffff:ffff:ffff:ffff:ffff:ffff
179231b:2000::/20231b:2fff:ffff:ffff:ffff:ffff:ffff:ffff
180231b:3000::/20231b:3fff:ffff:ffff:ffff:ffff:ffff:ffff
181231b:4000::/20231b:4fff:ffff:ffff:ffff:ffff:ffff:ffff
182231b:5000::/20231b:5fff:ffff:ffff:ffff:ffff:ffff:ffff
183231b:6000::/20231b:6fff:ffff:ffff:ffff:ffff:ffff:ffff
184231b:7000::/20231b:7fff:ffff:ffff:ffff:ffff:ffff:ffff
185231b:8000::/20231b:8fff:ffff:ffff:ffff:ffff:ffff:ffff
186231b:9000::/20231b:9fff:ffff:ffff:ffff:ffff:ffff:ffff
187231b:a000::/20231b:afff:ffff:ffff:ffff:ffff:ffff:ffff
188231b:b000::/20231b:bfff:ffff:ffff:ffff:ffff:ffff:ffff
189231b:c000::/20231b:cfff:ffff:ffff:ffff:ffff:ffff:ffff
190231b:d000::/20231b:dfff:ffff:ffff:ffff:ffff:ffff:ffff
191231b:e000::/20231b:efff:ffff:ffff:ffff:ffff:ffff:ffff
192231b:f000::/20231b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
193231c::/20231c:fff:ffff:ffff:ffff:ffff:ffff:ffff
194231c:1000::/20231c:1fff:ffff:ffff:ffff:ffff:ffff:ffff
195231c:2000::/20231c:2fff:ffff:ffff:ffff:ffff:ffff:ffff
196231c:3000::/20231c:3fff:ffff:ffff:ffff:ffff:ffff:ffff
197231c:4000::/20231c:4fff:ffff:ffff:ffff:ffff:ffff:ffff
198231c:5000::/20231c:5fff:ffff:ffff:ffff:ffff:ffff:ffff
199231c:6000::/20231c:6fff:ffff:ffff:ffff:ffff:ffff:ffff
200231c:7000::/20231c:7fff:ffff:ffff:ffff:ffff:ffff:ffff
201231c:8000::/20231c:8fff:ffff:ffff:ffff:ffff:ffff:ffff
202231c:9000::/20231c:9fff:ffff:ffff:ffff:ffff:ffff:ffff
203231c:a000::/20231c:afff:ffff:ffff:ffff:ffff:ffff:ffff
204231c:b000::/20231c:bfff:ffff:ffff:ffff:ffff:ffff:ffff
205231c:c000::/20231c:cfff:ffff:ffff:ffff:ffff:ffff:ffff
206231c:d000::/20231c:dfff:ffff:ffff:ffff:ffff:ffff:ffff
207231c:e000::/20231c:efff:ffff:ffff:ffff:ffff:ffff:ffff
208231c:f000::/20231c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
209231d::/20231d:fff:ffff:ffff:ffff:ffff:ffff:ffff
210231d:1000::/20231d:1fff:ffff:ffff:ffff:ffff:ffff:ffff
211231d:2000::/20231d:2fff:ffff:ffff:ffff:ffff:ffff:ffff
212231d:3000::/20231d:3fff:ffff:ffff:ffff:ffff:ffff:ffff
213231d:4000::/20231d:4fff:ffff:ffff:ffff:ffff:ffff:ffff
214231d:5000::/20231d:5fff:ffff:ffff:ffff:ffff:ffff:ffff
215231d:6000::/20231d:6fff:ffff:ffff:ffff:ffff:ffff:ffff
216231d:7000::/20231d:7fff:ffff:ffff:ffff:ffff:ffff:ffff
217231d:8000::/20231d:8fff:ffff:ffff:ffff:ffff:ffff:ffff
218231d:9000::/20231d:9fff:ffff:ffff:ffff:ffff:ffff:ffff
219231d:a000::/20231d:afff:ffff:ffff:ffff:ffff:ffff:ffff
220231d:b000::/20231d:bfff:ffff:ffff:ffff:ffff:ffff:ffff
221231d:c000::/20231d:cfff:ffff:ffff:ffff:ffff:ffff:ffff
222231d:d000::/20231d:dfff:ffff:ffff:ffff:ffff:ffff:ffff
223231d:e000::/20231d:efff:ffff:ffff:ffff:ffff:ffff:ffff
224231d:f000::/20231d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
225231e::/20231e:fff:ffff:ffff:ffff:ffff:ffff:ffff
226231e:1000::/20231e:1fff:ffff:ffff:ffff:ffff:ffff:ffff
227231e:2000::/20231e:2fff:ffff:ffff:ffff:ffff:ffff:ffff
228231e:3000::/20231e:3fff:ffff:ffff:ffff:ffff:ffff:ffff
229231e:4000::/20231e:4fff:ffff:ffff:ffff:ffff:ffff:ffff
230231e:5000::/20231e:5fff:ffff:ffff:ffff:ffff:ffff:ffff
231231e:6000::/20231e:6fff:ffff:ffff:ffff:ffff:ffff:ffff
232231e:7000::/20231e:7fff:ffff:ffff:ffff:ffff:ffff:ffff
233231e:8000::/20231e:8fff:ffff:ffff:ffff:ffff:ffff:ffff
234231e:9000::/20231e:9fff:ffff:ffff:ffff:ffff:ffff:ffff
235231e:a000::/20231e:afff:ffff:ffff:ffff:ffff:ffff:ffff
236231e:b000::/20231e:bfff:ffff:ffff:ffff:ffff:ffff:ffff
237231e:c000::/20231e:cfff:ffff:ffff:ffff:ffff:ffff:ffff
238231e:d000::/20231e:dfff:ffff:ffff:ffff:ffff:ffff:ffff
239231e:e000::/20231e:efff:ffff:ffff:ffff:ffff:ffff:ffff
240231e:f000::/20231e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
241231f::/20231f:fff:ffff:ffff:ffff:ffff:ffff:ffff
242231f:1000::/20231f:1fff:ffff:ffff:ffff:ffff:ffff:ffff
243231f:2000::/20231f:2fff:ffff:ffff:ffff:ffff:ffff:ffff
244231f:3000::/20231f:3fff:ffff:ffff:ffff:ffff:ffff:ffff
245231f:4000::/20231f:4fff:ffff:ffff:ffff:ffff:ffff:ffff
246231f:5000::/20231f:5fff:ffff:ffff:ffff:ffff:ffff:ffff
247231f:6000::/20231f:6fff:ffff:ffff:ffff:ffff:ffff:ffff
248231f:7000::/20231f:7fff:ffff:ffff:ffff:ffff:ffff:ffff
249231f:8000::/20231f:8fff:ffff:ffff:ffff:ffff:ffff:ffff
250231f:9000::/20231f:9fff:ffff:ffff:ffff:ffff:ffff:ffff
251231f:a000::/20231f:afff:ffff:ffff:ffff:ffff:ffff:ffff
252231f:b000::/20231f:bfff:ffff:ffff:ffff:ffff:ffff:ffff
253231f:c000::/20231f:cfff:ffff:ffff:ffff:ffff:ffff:ffff
254231f:d000::/20231f:dfff:ffff:ffff:ffff:ffff:ffff:ffff
255231f:e000::/20231f:efff:ffff:ffff:ffff:ffff:ffff:ffff
256231f:f000::/20231f: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.