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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
2730::/12
First address
2730::
Last address
273f: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
2730:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.7.2.ip6.arpa
Split into smaller subnets/20
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2730::/12 makes 256 subnets of /20.

Subnets
#SubnetLast address
12730::/202730:fff:ffff:ffff:ffff:ffff:ffff:ffff
22730:1000::/202730:1fff:ffff:ffff:ffff:ffff:ffff:ffff
32730:2000::/202730:2fff:ffff:ffff:ffff:ffff:ffff:ffff
42730:3000::/202730:3fff:ffff:ffff:ffff:ffff:ffff:ffff
52730:4000::/202730:4fff:ffff:ffff:ffff:ffff:ffff:ffff
62730:5000::/202730:5fff:ffff:ffff:ffff:ffff:ffff:ffff
72730:6000::/202730:6fff:ffff:ffff:ffff:ffff:ffff:ffff
82730:7000::/202730:7fff:ffff:ffff:ffff:ffff:ffff:ffff
92730:8000::/202730:8fff:ffff:ffff:ffff:ffff:ffff:ffff
102730:9000::/202730:9fff:ffff:ffff:ffff:ffff:ffff:ffff
112730:a000::/202730:afff:ffff:ffff:ffff:ffff:ffff:ffff
122730:b000::/202730:bfff:ffff:ffff:ffff:ffff:ffff:ffff
132730:c000::/202730:cfff:ffff:ffff:ffff:ffff:ffff:ffff
142730:d000::/202730:dfff:ffff:ffff:ffff:ffff:ffff:ffff
152730:e000::/202730:efff:ffff:ffff:ffff:ffff:ffff:ffff
162730:f000::/202730:ffff:ffff:ffff:ffff:ffff:ffff:ffff
172731::/202731:fff:ffff:ffff:ffff:ffff:ffff:ffff
182731:1000::/202731:1fff:ffff:ffff:ffff:ffff:ffff:ffff
192731:2000::/202731:2fff:ffff:ffff:ffff:ffff:ffff:ffff
202731:3000::/202731:3fff:ffff:ffff:ffff:ffff:ffff:ffff
212731:4000::/202731:4fff:ffff:ffff:ffff:ffff:ffff:ffff
222731:5000::/202731:5fff:ffff:ffff:ffff:ffff:ffff:ffff
232731:6000::/202731:6fff:ffff:ffff:ffff:ffff:ffff:ffff
242731:7000::/202731:7fff:ffff:ffff:ffff:ffff:ffff:ffff
252731:8000::/202731:8fff:ffff:ffff:ffff:ffff:ffff:ffff
262731:9000::/202731:9fff:ffff:ffff:ffff:ffff:ffff:ffff
272731:a000::/202731:afff:ffff:ffff:ffff:ffff:ffff:ffff
282731:b000::/202731:bfff:ffff:ffff:ffff:ffff:ffff:ffff
292731:c000::/202731:cfff:ffff:ffff:ffff:ffff:ffff:ffff
302731:d000::/202731:dfff:ffff:ffff:ffff:ffff:ffff:ffff
312731:e000::/202731:efff:ffff:ffff:ffff:ffff:ffff:ffff
322731:f000::/202731:ffff:ffff:ffff:ffff:ffff:ffff:ffff
332732::/202732:fff:ffff:ffff:ffff:ffff:ffff:ffff
342732:1000::/202732:1fff:ffff:ffff:ffff:ffff:ffff:ffff
352732:2000::/202732:2fff:ffff:ffff:ffff:ffff:ffff:ffff
362732:3000::/202732:3fff:ffff:ffff:ffff:ffff:ffff:ffff
372732:4000::/202732:4fff:ffff:ffff:ffff:ffff:ffff:ffff
382732:5000::/202732:5fff:ffff:ffff:ffff:ffff:ffff:ffff
392732:6000::/202732:6fff:ffff:ffff:ffff:ffff:ffff:ffff
402732:7000::/202732:7fff:ffff:ffff:ffff:ffff:ffff:ffff
412732:8000::/202732:8fff:ffff:ffff:ffff:ffff:ffff:ffff
422732:9000::/202732:9fff:ffff:ffff:ffff:ffff:ffff:ffff
432732:a000::/202732:afff:ffff:ffff:ffff:ffff:ffff:ffff
442732:b000::/202732:bfff:ffff:ffff:ffff:ffff:ffff:ffff
452732:c000::/202732:cfff:ffff:ffff:ffff:ffff:ffff:ffff
462732:d000::/202732:dfff:ffff:ffff:ffff:ffff:ffff:ffff
472732:e000::/202732:efff:ffff:ffff:ffff:ffff:ffff:ffff
482732:f000::/202732:ffff:ffff:ffff:ffff:ffff:ffff:ffff
492733::/202733:fff:ffff:ffff:ffff:ffff:ffff:ffff
502733:1000::/202733:1fff:ffff:ffff:ffff:ffff:ffff:ffff
512733:2000::/202733:2fff:ffff:ffff:ffff:ffff:ffff:ffff
522733:3000::/202733:3fff:ffff:ffff:ffff:ffff:ffff:ffff
532733:4000::/202733:4fff:ffff:ffff:ffff:ffff:ffff:ffff
542733:5000::/202733:5fff:ffff:ffff:ffff:ffff:ffff:ffff
552733:6000::/202733:6fff:ffff:ffff:ffff:ffff:ffff:ffff
562733:7000::/202733:7fff:ffff:ffff:ffff:ffff:ffff:ffff
572733:8000::/202733:8fff:ffff:ffff:ffff:ffff:ffff:ffff
582733:9000::/202733:9fff:ffff:ffff:ffff:ffff:ffff:ffff
592733:a000::/202733:afff:ffff:ffff:ffff:ffff:ffff:ffff
602733:b000::/202733:bfff:ffff:ffff:ffff:ffff:ffff:ffff
612733:c000::/202733:cfff:ffff:ffff:ffff:ffff:ffff:ffff
622733:d000::/202733:dfff:ffff:ffff:ffff:ffff:ffff:ffff
632733:e000::/202733:efff:ffff:ffff:ffff:ffff:ffff:ffff
642733:f000::/202733:ffff:ffff:ffff:ffff:ffff:ffff:ffff
652734::/202734:fff:ffff:ffff:ffff:ffff:ffff:ffff
662734:1000::/202734:1fff:ffff:ffff:ffff:ffff:ffff:ffff
672734:2000::/202734:2fff:ffff:ffff:ffff:ffff:ffff:ffff
682734:3000::/202734:3fff:ffff:ffff:ffff:ffff:ffff:ffff
692734:4000::/202734:4fff:ffff:ffff:ffff:ffff:ffff:ffff
702734:5000::/202734:5fff:ffff:ffff:ffff:ffff:ffff:ffff
712734:6000::/202734:6fff:ffff:ffff:ffff:ffff:ffff:ffff
722734:7000::/202734:7fff:ffff:ffff:ffff:ffff:ffff:ffff
732734:8000::/202734:8fff:ffff:ffff:ffff:ffff:ffff:ffff
742734:9000::/202734:9fff:ffff:ffff:ffff:ffff:ffff:ffff
752734:a000::/202734:afff:ffff:ffff:ffff:ffff:ffff:ffff
762734:b000::/202734:bfff:ffff:ffff:ffff:ffff:ffff:ffff
772734:c000::/202734:cfff:ffff:ffff:ffff:ffff:ffff:ffff
782734:d000::/202734:dfff:ffff:ffff:ffff:ffff:ffff:ffff
792734:e000::/202734:efff:ffff:ffff:ffff:ffff:ffff:ffff
802734:f000::/202734:ffff:ffff:ffff:ffff:ffff:ffff:ffff
812735::/202735:fff:ffff:ffff:ffff:ffff:ffff:ffff
822735:1000::/202735:1fff:ffff:ffff:ffff:ffff:ffff:ffff
832735:2000::/202735:2fff:ffff:ffff:ffff:ffff:ffff:ffff
842735:3000::/202735:3fff:ffff:ffff:ffff:ffff:ffff:ffff
852735:4000::/202735:4fff:ffff:ffff:ffff:ffff:ffff:ffff
862735:5000::/202735:5fff:ffff:ffff:ffff:ffff:ffff:ffff
872735:6000::/202735:6fff:ffff:ffff:ffff:ffff:ffff:ffff
882735:7000::/202735:7fff:ffff:ffff:ffff:ffff:ffff:ffff
892735:8000::/202735:8fff:ffff:ffff:ffff:ffff:ffff:ffff
902735:9000::/202735:9fff:ffff:ffff:ffff:ffff:ffff:ffff
912735:a000::/202735:afff:ffff:ffff:ffff:ffff:ffff:ffff
922735:b000::/202735:bfff:ffff:ffff:ffff:ffff:ffff:ffff
932735:c000::/202735:cfff:ffff:ffff:ffff:ffff:ffff:ffff
942735:d000::/202735:dfff:ffff:ffff:ffff:ffff:ffff:ffff
952735:e000::/202735:efff:ffff:ffff:ffff:ffff:ffff:ffff
962735:f000::/202735:ffff:ffff:ffff:ffff:ffff:ffff:ffff
972736::/202736:fff:ffff:ffff:ffff:ffff:ffff:ffff
982736:1000::/202736:1fff:ffff:ffff:ffff:ffff:ffff:ffff
992736:2000::/202736:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1002736:3000::/202736:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1012736:4000::/202736:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1022736:5000::/202736:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1032736:6000::/202736:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1042736:7000::/202736:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1052736:8000::/202736:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1062736:9000::/202736:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1072736:a000::/202736:afff:ffff:ffff:ffff:ffff:ffff:ffff
1082736:b000::/202736:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1092736:c000::/202736:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1102736:d000::/202736:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1112736:e000::/202736:efff:ffff:ffff:ffff:ffff:ffff:ffff
1122736:f000::/202736:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1132737::/202737:fff:ffff:ffff:ffff:ffff:ffff:ffff
1142737:1000::/202737:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1152737:2000::/202737:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1162737:3000::/202737:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1172737:4000::/202737:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1182737:5000::/202737:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1192737:6000::/202737:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1202737:7000::/202737:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1212737:8000::/202737:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1222737:9000::/202737:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1232737:a000::/202737:afff:ffff:ffff:ffff:ffff:ffff:ffff
1242737:b000::/202737:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1252737:c000::/202737:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1262737:d000::/202737:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1272737:e000::/202737:efff:ffff:ffff:ffff:ffff:ffff:ffff
1282737:f000::/202737:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1292738::/202738:fff:ffff:ffff:ffff:ffff:ffff:ffff
1302738:1000::/202738:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1312738:2000::/202738:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1322738:3000::/202738:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1332738:4000::/202738:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1342738:5000::/202738:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1352738:6000::/202738:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1362738:7000::/202738:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1372738:8000::/202738:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1382738:9000::/202738:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1392738:a000::/202738:afff:ffff:ffff:ffff:ffff:ffff:ffff
1402738:b000::/202738:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1412738:c000::/202738:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1422738:d000::/202738:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1432738:e000::/202738:efff:ffff:ffff:ffff:ffff:ffff:ffff
1442738:f000::/202738:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1452739::/202739:fff:ffff:ffff:ffff:ffff:ffff:ffff
1462739:1000::/202739:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1472739:2000::/202739:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1482739:3000::/202739:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1492739:4000::/202739:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1502739:5000::/202739:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1512739:6000::/202739:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1522739:7000::/202739:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1532739:8000::/202739:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1542739:9000::/202739:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1552739:a000::/202739:afff:ffff:ffff:ffff:ffff:ffff:ffff
1562739:b000::/202739:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1572739:c000::/202739:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1582739:d000::/202739:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1592739:e000::/202739:efff:ffff:ffff:ffff:ffff:ffff:ffff
1602739:f000::/202739:ffff:ffff:ffff:ffff:ffff:ffff:ffff
161273a::/20273a:fff:ffff:ffff:ffff:ffff:ffff:ffff
162273a:1000::/20273a:1fff:ffff:ffff:ffff:ffff:ffff:ffff
163273a:2000::/20273a:2fff:ffff:ffff:ffff:ffff:ffff:ffff
164273a:3000::/20273a:3fff:ffff:ffff:ffff:ffff:ffff:ffff
165273a:4000::/20273a:4fff:ffff:ffff:ffff:ffff:ffff:ffff
166273a:5000::/20273a:5fff:ffff:ffff:ffff:ffff:ffff:ffff
167273a:6000::/20273a:6fff:ffff:ffff:ffff:ffff:ffff:ffff
168273a:7000::/20273a:7fff:ffff:ffff:ffff:ffff:ffff:ffff
169273a:8000::/20273a:8fff:ffff:ffff:ffff:ffff:ffff:ffff
170273a:9000::/20273a:9fff:ffff:ffff:ffff:ffff:ffff:ffff
171273a:a000::/20273a:afff:ffff:ffff:ffff:ffff:ffff:ffff
172273a:b000::/20273a:bfff:ffff:ffff:ffff:ffff:ffff:ffff
173273a:c000::/20273a:cfff:ffff:ffff:ffff:ffff:ffff:ffff
174273a:d000::/20273a:dfff:ffff:ffff:ffff:ffff:ffff:ffff
175273a:e000::/20273a:efff:ffff:ffff:ffff:ffff:ffff:ffff
176273a:f000::/20273a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
177273b::/20273b:fff:ffff:ffff:ffff:ffff:ffff:ffff
178273b:1000::/20273b:1fff:ffff:ffff:ffff:ffff:ffff:ffff
179273b:2000::/20273b:2fff:ffff:ffff:ffff:ffff:ffff:ffff
180273b:3000::/20273b:3fff:ffff:ffff:ffff:ffff:ffff:ffff
181273b:4000::/20273b:4fff:ffff:ffff:ffff:ffff:ffff:ffff
182273b:5000::/20273b:5fff:ffff:ffff:ffff:ffff:ffff:ffff
183273b:6000::/20273b:6fff:ffff:ffff:ffff:ffff:ffff:ffff
184273b:7000::/20273b:7fff:ffff:ffff:ffff:ffff:ffff:ffff
185273b:8000::/20273b:8fff:ffff:ffff:ffff:ffff:ffff:ffff
186273b:9000::/20273b:9fff:ffff:ffff:ffff:ffff:ffff:ffff
187273b:a000::/20273b:afff:ffff:ffff:ffff:ffff:ffff:ffff
188273b:b000::/20273b:bfff:ffff:ffff:ffff:ffff:ffff:ffff
189273b:c000::/20273b:cfff:ffff:ffff:ffff:ffff:ffff:ffff
190273b:d000::/20273b:dfff:ffff:ffff:ffff:ffff:ffff:ffff
191273b:e000::/20273b:efff:ffff:ffff:ffff:ffff:ffff:ffff
192273b:f000::/20273b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
193273c::/20273c:fff:ffff:ffff:ffff:ffff:ffff:ffff
194273c:1000::/20273c:1fff:ffff:ffff:ffff:ffff:ffff:ffff
195273c:2000::/20273c:2fff:ffff:ffff:ffff:ffff:ffff:ffff
196273c:3000::/20273c:3fff:ffff:ffff:ffff:ffff:ffff:ffff
197273c:4000::/20273c:4fff:ffff:ffff:ffff:ffff:ffff:ffff
198273c:5000::/20273c:5fff:ffff:ffff:ffff:ffff:ffff:ffff
199273c:6000::/20273c:6fff:ffff:ffff:ffff:ffff:ffff:ffff
200273c:7000::/20273c:7fff:ffff:ffff:ffff:ffff:ffff:ffff
201273c:8000::/20273c:8fff:ffff:ffff:ffff:ffff:ffff:ffff
202273c:9000::/20273c:9fff:ffff:ffff:ffff:ffff:ffff:ffff
203273c:a000::/20273c:afff:ffff:ffff:ffff:ffff:ffff:ffff
204273c:b000::/20273c:bfff:ffff:ffff:ffff:ffff:ffff:ffff
205273c:c000::/20273c:cfff:ffff:ffff:ffff:ffff:ffff:ffff
206273c:d000::/20273c:dfff:ffff:ffff:ffff:ffff:ffff:ffff
207273c:e000::/20273c:efff:ffff:ffff:ffff:ffff:ffff:ffff
208273c:f000::/20273c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
209273d::/20273d:fff:ffff:ffff:ffff:ffff:ffff:ffff
210273d:1000::/20273d:1fff:ffff:ffff:ffff:ffff:ffff:ffff
211273d:2000::/20273d:2fff:ffff:ffff:ffff:ffff:ffff:ffff
212273d:3000::/20273d:3fff:ffff:ffff:ffff:ffff:ffff:ffff
213273d:4000::/20273d:4fff:ffff:ffff:ffff:ffff:ffff:ffff
214273d:5000::/20273d:5fff:ffff:ffff:ffff:ffff:ffff:ffff
215273d:6000::/20273d:6fff:ffff:ffff:ffff:ffff:ffff:ffff
216273d:7000::/20273d:7fff:ffff:ffff:ffff:ffff:ffff:ffff
217273d:8000::/20273d:8fff:ffff:ffff:ffff:ffff:ffff:ffff
218273d:9000::/20273d:9fff:ffff:ffff:ffff:ffff:ffff:ffff
219273d:a000::/20273d:afff:ffff:ffff:ffff:ffff:ffff:ffff
220273d:b000::/20273d:bfff:ffff:ffff:ffff:ffff:ffff:ffff
221273d:c000::/20273d:cfff:ffff:ffff:ffff:ffff:ffff:ffff
222273d:d000::/20273d:dfff:ffff:ffff:ffff:ffff:ffff:ffff
223273d:e000::/20273d:efff:ffff:ffff:ffff:ffff:ffff:ffff
224273d:f000::/20273d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
225273e::/20273e:fff:ffff:ffff:ffff:ffff:ffff:ffff
226273e:1000::/20273e:1fff:ffff:ffff:ffff:ffff:ffff:ffff
227273e:2000::/20273e:2fff:ffff:ffff:ffff:ffff:ffff:ffff
228273e:3000::/20273e:3fff:ffff:ffff:ffff:ffff:ffff:ffff
229273e:4000::/20273e:4fff:ffff:ffff:ffff:ffff:ffff:ffff
230273e:5000::/20273e:5fff:ffff:ffff:ffff:ffff:ffff:ffff
231273e:6000::/20273e:6fff:ffff:ffff:ffff:ffff:ffff:ffff
232273e:7000::/20273e:7fff:ffff:ffff:ffff:ffff:ffff:ffff
233273e:8000::/20273e:8fff:ffff:ffff:ffff:ffff:ffff:ffff
234273e:9000::/20273e:9fff:ffff:ffff:ffff:ffff:ffff:ffff
235273e:a000::/20273e:afff:ffff:ffff:ffff:ffff:ffff:ffff
236273e:b000::/20273e:bfff:ffff:ffff:ffff:ffff:ffff:ffff
237273e:c000::/20273e:cfff:ffff:ffff:ffff:ffff:ffff:ffff
238273e:d000::/20273e:dfff:ffff:ffff:ffff:ffff:ffff:ffff
239273e:e000::/20273e:efff:ffff:ffff:ffff:ffff:ffff:ffff
240273e:f000::/20273e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
241273f::/20273f:fff:ffff:ffff:ffff:ffff:ffff:ffff
242273f:1000::/20273f:1fff:ffff:ffff:ffff:ffff:ffff:ffff
243273f:2000::/20273f:2fff:ffff:ffff:ffff:ffff:ffff:ffff
244273f:3000::/20273f:3fff:ffff:ffff:ffff:ffff:ffff:ffff
245273f:4000::/20273f:4fff:ffff:ffff:ffff:ffff:ffff:ffff
246273f:5000::/20273f:5fff:ffff:ffff:ffff:ffff:ffff:ffff
247273f:6000::/20273f:6fff:ffff:ffff:ffff:ffff:ffff:ffff
248273f:7000::/20273f:7fff:ffff:ffff:ffff:ffff:ffff:ffff
249273f:8000::/20273f:8fff:ffff:ffff:ffff:ffff:ffff:ffff
250273f:9000::/20273f:9fff:ffff:ffff:ffff:ffff:ffff:ffff
251273f:a000::/20273f:afff:ffff:ffff:ffff:ffff:ffff:ffff
252273f:b000::/20273f:bfff:ffff:ffff:ffff:ffff:ffff:ffff
253273f:c000::/20273f:cfff:ffff:ffff:ffff:ffff:ffff:ffff
254273f:d000::/20273f:dfff:ffff:ffff:ffff:ffff:ffff:ffff
255273f:e000::/20273f:efff:ffff:ffff:ffff:ffff:ffff:ffff
256273f:f000::/20273f: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.