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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
2350::/12
First address
2350::
Last address
235f: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
2350:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
5.3.2.ip6.arpa
Split into smaller subnets/20
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2350::/12 makes 256 subnets of /20.

Subnets
#SubnetLast address
12350::/202350:fff:ffff:ffff:ffff:ffff:ffff:ffff
22350:1000::/202350:1fff:ffff:ffff:ffff:ffff:ffff:ffff
32350:2000::/202350:2fff:ffff:ffff:ffff:ffff:ffff:ffff
42350:3000::/202350:3fff:ffff:ffff:ffff:ffff:ffff:ffff
52350:4000::/202350:4fff:ffff:ffff:ffff:ffff:ffff:ffff
62350:5000::/202350:5fff:ffff:ffff:ffff:ffff:ffff:ffff
72350:6000::/202350:6fff:ffff:ffff:ffff:ffff:ffff:ffff
82350:7000::/202350:7fff:ffff:ffff:ffff:ffff:ffff:ffff
92350:8000::/202350:8fff:ffff:ffff:ffff:ffff:ffff:ffff
102350:9000::/202350:9fff:ffff:ffff:ffff:ffff:ffff:ffff
112350:a000::/202350:afff:ffff:ffff:ffff:ffff:ffff:ffff
122350:b000::/202350:bfff:ffff:ffff:ffff:ffff:ffff:ffff
132350:c000::/202350:cfff:ffff:ffff:ffff:ffff:ffff:ffff
142350:d000::/202350:dfff:ffff:ffff:ffff:ffff:ffff:ffff
152350:e000::/202350:efff:ffff:ffff:ffff:ffff:ffff:ffff
162350:f000::/202350:ffff:ffff:ffff:ffff:ffff:ffff:ffff
172351::/202351:fff:ffff:ffff:ffff:ffff:ffff:ffff
182351:1000::/202351:1fff:ffff:ffff:ffff:ffff:ffff:ffff
192351:2000::/202351:2fff:ffff:ffff:ffff:ffff:ffff:ffff
202351:3000::/202351:3fff:ffff:ffff:ffff:ffff:ffff:ffff
212351:4000::/202351:4fff:ffff:ffff:ffff:ffff:ffff:ffff
222351:5000::/202351:5fff:ffff:ffff:ffff:ffff:ffff:ffff
232351:6000::/202351:6fff:ffff:ffff:ffff:ffff:ffff:ffff
242351:7000::/202351:7fff:ffff:ffff:ffff:ffff:ffff:ffff
252351:8000::/202351:8fff:ffff:ffff:ffff:ffff:ffff:ffff
262351:9000::/202351:9fff:ffff:ffff:ffff:ffff:ffff:ffff
272351:a000::/202351:afff:ffff:ffff:ffff:ffff:ffff:ffff
282351:b000::/202351:bfff:ffff:ffff:ffff:ffff:ffff:ffff
292351:c000::/202351:cfff:ffff:ffff:ffff:ffff:ffff:ffff
302351:d000::/202351:dfff:ffff:ffff:ffff:ffff:ffff:ffff
312351:e000::/202351:efff:ffff:ffff:ffff:ffff:ffff:ffff
322351:f000::/202351:ffff:ffff:ffff:ffff:ffff:ffff:ffff
332352::/202352:fff:ffff:ffff:ffff:ffff:ffff:ffff
342352:1000::/202352:1fff:ffff:ffff:ffff:ffff:ffff:ffff
352352:2000::/202352:2fff:ffff:ffff:ffff:ffff:ffff:ffff
362352:3000::/202352:3fff:ffff:ffff:ffff:ffff:ffff:ffff
372352:4000::/202352:4fff:ffff:ffff:ffff:ffff:ffff:ffff
382352:5000::/202352:5fff:ffff:ffff:ffff:ffff:ffff:ffff
392352:6000::/202352:6fff:ffff:ffff:ffff:ffff:ffff:ffff
402352:7000::/202352:7fff:ffff:ffff:ffff:ffff:ffff:ffff
412352:8000::/202352:8fff:ffff:ffff:ffff:ffff:ffff:ffff
422352:9000::/202352:9fff:ffff:ffff:ffff:ffff:ffff:ffff
432352:a000::/202352:afff:ffff:ffff:ffff:ffff:ffff:ffff
442352:b000::/202352:bfff:ffff:ffff:ffff:ffff:ffff:ffff
452352:c000::/202352:cfff:ffff:ffff:ffff:ffff:ffff:ffff
462352:d000::/202352:dfff:ffff:ffff:ffff:ffff:ffff:ffff
472352:e000::/202352:efff:ffff:ffff:ffff:ffff:ffff:ffff
482352:f000::/202352:ffff:ffff:ffff:ffff:ffff:ffff:ffff
492353::/202353:fff:ffff:ffff:ffff:ffff:ffff:ffff
502353:1000::/202353:1fff:ffff:ffff:ffff:ffff:ffff:ffff
512353:2000::/202353:2fff:ffff:ffff:ffff:ffff:ffff:ffff
522353:3000::/202353:3fff:ffff:ffff:ffff:ffff:ffff:ffff
532353:4000::/202353:4fff:ffff:ffff:ffff:ffff:ffff:ffff
542353:5000::/202353:5fff:ffff:ffff:ffff:ffff:ffff:ffff
552353:6000::/202353:6fff:ffff:ffff:ffff:ffff:ffff:ffff
562353:7000::/202353:7fff:ffff:ffff:ffff:ffff:ffff:ffff
572353:8000::/202353:8fff:ffff:ffff:ffff:ffff:ffff:ffff
582353:9000::/202353:9fff:ffff:ffff:ffff:ffff:ffff:ffff
592353:a000::/202353:afff:ffff:ffff:ffff:ffff:ffff:ffff
602353:b000::/202353:bfff:ffff:ffff:ffff:ffff:ffff:ffff
612353:c000::/202353:cfff:ffff:ffff:ffff:ffff:ffff:ffff
622353:d000::/202353:dfff:ffff:ffff:ffff:ffff:ffff:ffff
632353:e000::/202353:efff:ffff:ffff:ffff:ffff:ffff:ffff
642353:f000::/202353:ffff:ffff:ffff:ffff:ffff:ffff:ffff
652354::/202354:fff:ffff:ffff:ffff:ffff:ffff:ffff
662354:1000::/202354:1fff:ffff:ffff:ffff:ffff:ffff:ffff
672354:2000::/202354:2fff:ffff:ffff:ffff:ffff:ffff:ffff
682354:3000::/202354:3fff:ffff:ffff:ffff:ffff:ffff:ffff
692354:4000::/202354:4fff:ffff:ffff:ffff:ffff:ffff:ffff
702354:5000::/202354:5fff:ffff:ffff:ffff:ffff:ffff:ffff
712354:6000::/202354:6fff:ffff:ffff:ffff:ffff:ffff:ffff
722354:7000::/202354:7fff:ffff:ffff:ffff:ffff:ffff:ffff
732354:8000::/202354:8fff:ffff:ffff:ffff:ffff:ffff:ffff
742354:9000::/202354:9fff:ffff:ffff:ffff:ffff:ffff:ffff
752354:a000::/202354:afff:ffff:ffff:ffff:ffff:ffff:ffff
762354:b000::/202354:bfff:ffff:ffff:ffff:ffff:ffff:ffff
772354:c000::/202354:cfff:ffff:ffff:ffff:ffff:ffff:ffff
782354:d000::/202354:dfff:ffff:ffff:ffff:ffff:ffff:ffff
792354:e000::/202354:efff:ffff:ffff:ffff:ffff:ffff:ffff
802354:f000::/202354:ffff:ffff:ffff:ffff:ffff:ffff:ffff
812355::/202355:fff:ffff:ffff:ffff:ffff:ffff:ffff
822355:1000::/202355:1fff:ffff:ffff:ffff:ffff:ffff:ffff
832355:2000::/202355:2fff:ffff:ffff:ffff:ffff:ffff:ffff
842355:3000::/202355:3fff:ffff:ffff:ffff:ffff:ffff:ffff
852355:4000::/202355:4fff:ffff:ffff:ffff:ffff:ffff:ffff
862355:5000::/202355:5fff:ffff:ffff:ffff:ffff:ffff:ffff
872355:6000::/202355:6fff:ffff:ffff:ffff:ffff:ffff:ffff
882355:7000::/202355:7fff:ffff:ffff:ffff:ffff:ffff:ffff
892355:8000::/202355:8fff:ffff:ffff:ffff:ffff:ffff:ffff
902355:9000::/202355:9fff:ffff:ffff:ffff:ffff:ffff:ffff
912355:a000::/202355:afff:ffff:ffff:ffff:ffff:ffff:ffff
922355:b000::/202355:bfff:ffff:ffff:ffff:ffff:ffff:ffff
932355:c000::/202355:cfff:ffff:ffff:ffff:ffff:ffff:ffff
942355:d000::/202355:dfff:ffff:ffff:ffff:ffff:ffff:ffff
952355:e000::/202355:efff:ffff:ffff:ffff:ffff:ffff:ffff
962355:f000::/202355:ffff:ffff:ffff:ffff:ffff:ffff:ffff
972356::/202356:fff:ffff:ffff:ffff:ffff:ffff:ffff
982356:1000::/202356:1fff:ffff:ffff:ffff:ffff:ffff:ffff
992356:2000::/202356:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1002356:3000::/202356:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1012356:4000::/202356:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1022356:5000::/202356:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1032356:6000::/202356:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1042356:7000::/202356:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1052356:8000::/202356:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1062356:9000::/202356:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1072356:a000::/202356:afff:ffff:ffff:ffff:ffff:ffff:ffff
1082356:b000::/202356:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1092356:c000::/202356:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1102356:d000::/202356:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1112356:e000::/202356:efff:ffff:ffff:ffff:ffff:ffff:ffff
1122356:f000::/202356:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1132357::/202357:fff:ffff:ffff:ffff:ffff:ffff:ffff
1142357:1000::/202357:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1152357:2000::/202357:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1162357:3000::/202357:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1172357:4000::/202357:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1182357:5000::/202357:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1192357:6000::/202357:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1202357:7000::/202357:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1212357:8000::/202357:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1222357:9000::/202357:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1232357:a000::/202357:afff:ffff:ffff:ffff:ffff:ffff:ffff
1242357:b000::/202357:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1252357:c000::/202357:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1262357:d000::/202357:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1272357:e000::/202357:efff:ffff:ffff:ffff:ffff:ffff:ffff
1282357:f000::/202357:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1292358::/202358:fff:ffff:ffff:ffff:ffff:ffff:ffff
1302358:1000::/202358:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1312358:2000::/202358:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1322358:3000::/202358:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1332358:4000::/202358:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1342358:5000::/202358:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1352358:6000::/202358:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1362358:7000::/202358:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1372358:8000::/202358:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1382358:9000::/202358:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1392358:a000::/202358:afff:ffff:ffff:ffff:ffff:ffff:ffff
1402358:b000::/202358:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1412358:c000::/202358:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1422358:d000::/202358:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1432358:e000::/202358:efff:ffff:ffff:ffff:ffff:ffff:ffff
1442358:f000::/202358:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1452359::/202359:fff:ffff:ffff:ffff:ffff:ffff:ffff
1462359:1000::/202359:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1472359:2000::/202359:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1482359:3000::/202359:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1492359:4000::/202359:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1502359:5000::/202359:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1512359:6000::/202359:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1522359:7000::/202359:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1532359:8000::/202359:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1542359:9000::/202359:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1552359:a000::/202359:afff:ffff:ffff:ffff:ffff:ffff:ffff
1562359:b000::/202359:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1572359:c000::/202359:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1582359:d000::/202359:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1592359:e000::/202359:efff:ffff:ffff:ffff:ffff:ffff:ffff
1602359:f000::/202359:ffff:ffff:ffff:ffff:ffff:ffff:ffff
161235a::/20235a:fff:ffff:ffff:ffff:ffff:ffff:ffff
162235a:1000::/20235a:1fff:ffff:ffff:ffff:ffff:ffff:ffff
163235a:2000::/20235a:2fff:ffff:ffff:ffff:ffff:ffff:ffff
164235a:3000::/20235a:3fff:ffff:ffff:ffff:ffff:ffff:ffff
165235a:4000::/20235a:4fff:ffff:ffff:ffff:ffff:ffff:ffff
166235a:5000::/20235a:5fff:ffff:ffff:ffff:ffff:ffff:ffff
167235a:6000::/20235a:6fff:ffff:ffff:ffff:ffff:ffff:ffff
168235a:7000::/20235a:7fff:ffff:ffff:ffff:ffff:ffff:ffff
169235a:8000::/20235a:8fff:ffff:ffff:ffff:ffff:ffff:ffff
170235a:9000::/20235a:9fff:ffff:ffff:ffff:ffff:ffff:ffff
171235a:a000::/20235a:afff:ffff:ffff:ffff:ffff:ffff:ffff
172235a:b000::/20235a:bfff:ffff:ffff:ffff:ffff:ffff:ffff
173235a:c000::/20235a:cfff:ffff:ffff:ffff:ffff:ffff:ffff
174235a:d000::/20235a:dfff:ffff:ffff:ffff:ffff:ffff:ffff
175235a:e000::/20235a:efff:ffff:ffff:ffff:ffff:ffff:ffff
176235a:f000::/20235a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
177235b::/20235b:fff:ffff:ffff:ffff:ffff:ffff:ffff
178235b:1000::/20235b:1fff:ffff:ffff:ffff:ffff:ffff:ffff
179235b:2000::/20235b:2fff:ffff:ffff:ffff:ffff:ffff:ffff
180235b:3000::/20235b:3fff:ffff:ffff:ffff:ffff:ffff:ffff
181235b:4000::/20235b:4fff:ffff:ffff:ffff:ffff:ffff:ffff
182235b:5000::/20235b:5fff:ffff:ffff:ffff:ffff:ffff:ffff
183235b:6000::/20235b:6fff:ffff:ffff:ffff:ffff:ffff:ffff
184235b:7000::/20235b:7fff:ffff:ffff:ffff:ffff:ffff:ffff
185235b:8000::/20235b:8fff:ffff:ffff:ffff:ffff:ffff:ffff
186235b:9000::/20235b:9fff:ffff:ffff:ffff:ffff:ffff:ffff
187235b:a000::/20235b:afff:ffff:ffff:ffff:ffff:ffff:ffff
188235b:b000::/20235b:bfff:ffff:ffff:ffff:ffff:ffff:ffff
189235b:c000::/20235b:cfff:ffff:ffff:ffff:ffff:ffff:ffff
190235b:d000::/20235b:dfff:ffff:ffff:ffff:ffff:ffff:ffff
191235b:e000::/20235b:efff:ffff:ffff:ffff:ffff:ffff:ffff
192235b:f000::/20235b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
193235c::/20235c:fff:ffff:ffff:ffff:ffff:ffff:ffff
194235c:1000::/20235c:1fff:ffff:ffff:ffff:ffff:ffff:ffff
195235c:2000::/20235c:2fff:ffff:ffff:ffff:ffff:ffff:ffff
196235c:3000::/20235c:3fff:ffff:ffff:ffff:ffff:ffff:ffff
197235c:4000::/20235c:4fff:ffff:ffff:ffff:ffff:ffff:ffff
198235c:5000::/20235c:5fff:ffff:ffff:ffff:ffff:ffff:ffff
199235c:6000::/20235c:6fff:ffff:ffff:ffff:ffff:ffff:ffff
200235c:7000::/20235c:7fff:ffff:ffff:ffff:ffff:ffff:ffff
201235c:8000::/20235c:8fff:ffff:ffff:ffff:ffff:ffff:ffff
202235c:9000::/20235c:9fff:ffff:ffff:ffff:ffff:ffff:ffff
203235c:a000::/20235c:afff:ffff:ffff:ffff:ffff:ffff:ffff
204235c:b000::/20235c:bfff:ffff:ffff:ffff:ffff:ffff:ffff
205235c:c000::/20235c:cfff:ffff:ffff:ffff:ffff:ffff:ffff
206235c:d000::/20235c:dfff:ffff:ffff:ffff:ffff:ffff:ffff
207235c:e000::/20235c:efff:ffff:ffff:ffff:ffff:ffff:ffff
208235c:f000::/20235c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
209235d::/20235d:fff:ffff:ffff:ffff:ffff:ffff:ffff
210235d:1000::/20235d:1fff:ffff:ffff:ffff:ffff:ffff:ffff
211235d:2000::/20235d:2fff:ffff:ffff:ffff:ffff:ffff:ffff
212235d:3000::/20235d:3fff:ffff:ffff:ffff:ffff:ffff:ffff
213235d:4000::/20235d:4fff:ffff:ffff:ffff:ffff:ffff:ffff
214235d:5000::/20235d:5fff:ffff:ffff:ffff:ffff:ffff:ffff
215235d:6000::/20235d:6fff:ffff:ffff:ffff:ffff:ffff:ffff
216235d:7000::/20235d:7fff:ffff:ffff:ffff:ffff:ffff:ffff
217235d:8000::/20235d:8fff:ffff:ffff:ffff:ffff:ffff:ffff
218235d:9000::/20235d:9fff:ffff:ffff:ffff:ffff:ffff:ffff
219235d:a000::/20235d:afff:ffff:ffff:ffff:ffff:ffff:ffff
220235d:b000::/20235d:bfff:ffff:ffff:ffff:ffff:ffff:ffff
221235d:c000::/20235d:cfff:ffff:ffff:ffff:ffff:ffff:ffff
222235d:d000::/20235d:dfff:ffff:ffff:ffff:ffff:ffff:ffff
223235d:e000::/20235d:efff:ffff:ffff:ffff:ffff:ffff:ffff
224235d:f000::/20235d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
225235e::/20235e:fff:ffff:ffff:ffff:ffff:ffff:ffff
226235e:1000::/20235e:1fff:ffff:ffff:ffff:ffff:ffff:ffff
227235e:2000::/20235e:2fff:ffff:ffff:ffff:ffff:ffff:ffff
228235e:3000::/20235e:3fff:ffff:ffff:ffff:ffff:ffff:ffff
229235e:4000::/20235e:4fff:ffff:ffff:ffff:ffff:ffff:ffff
230235e:5000::/20235e:5fff:ffff:ffff:ffff:ffff:ffff:ffff
231235e:6000::/20235e:6fff:ffff:ffff:ffff:ffff:ffff:ffff
232235e:7000::/20235e:7fff:ffff:ffff:ffff:ffff:ffff:ffff
233235e:8000::/20235e:8fff:ffff:ffff:ffff:ffff:ffff:ffff
234235e:9000::/20235e:9fff:ffff:ffff:ffff:ffff:ffff:ffff
235235e:a000::/20235e:afff:ffff:ffff:ffff:ffff:ffff:ffff
236235e:b000::/20235e:bfff:ffff:ffff:ffff:ffff:ffff:ffff
237235e:c000::/20235e:cfff:ffff:ffff:ffff:ffff:ffff:ffff
238235e:d000::/20235e:dfff:ffff:ffff:ffff:ffff:ffff:ffff
239235e:e000::/20235e:efff:ffff:ffff:ffff:ffff:ffff:ffff
240235e:f000::/20235e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
241235f::/20235f:fff:ffff:ffff:ffff:ffff:ffff:ffff
242235f:1000::/20235f:1fff:ffff:ffff:ffff:ffff:ffff:ffff
243235f:2000::/20235f:2fff:ffff:ffff:ffff:ffff:ffff:ffff
244235f:3000::/20235f:3fff:ffff:ffff:ffff:ffff:ffff:ffff
245235f:4000::/20235f:4fff:ffff:ffff:ffff:ffff:ffff:ffff
246235f:5000::/20235f:5fff:ffff:ffff:ffff:ffff:ffff:ffff
247235f:6000::/20235f:6fff:ffff:ffff:ffff:ffff:ffff:ffff
248235f:7000::/20235f:7fff:ffff:ffff:ffff:ffff:ffff:ffff
249235f:8000::/20235f:8fff:ffff:ffff:ffff:ffff:ffff:ffff
250235f:9000::/20235f:9fff:ffff:ffff:ffff:ffff:ffff:ffff
251235f:a000::/20235f:afff:ffff:ffff:ffff:ffff:ffff:ffff
252235f:b000::/20235f:bfff:ffff:ffff:ffff:ffff:ffff:ffff
253235f:c000::/20235f:cfff:ffff:ffff:ffff:ffff:ffff:ffff
254235f:d000::/20235f:dfff:ffff:ffff:ffff:ffff:ffff:ffff
255235f:e000::/20235f:efff:ffff:ffff:ffff:ffff:ffff:ffff
256235f:f000::/20235f: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.