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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
2780::/12
First address
2780::
Last address
278f: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
2780:0000:0000:0000:0000:0000:0000:0000
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.7.2.ip6.arpa
Split into smaller subnets/20
/13 (2)/14 (4)/15 (8)/16 (16)/20 (256)/24 (4,096)/28 (65,536)

2780::/12 makes 256 subnets of /20.

Subnets
#SubnetLast address
12780::/202780:fff:ffff:ffff:ffff:ffff:ffff:ffff
22780:1000::/202780:1fff:ffff:ffff:ffff:ffff:ffff:ffff
32780:2000::/202780:2fff:ffff:ffff:ffff:ffff:ffff:ffff
42780:3000::/202780:3fff:ffff:ffff:ffff:ffff:ffff:ffff
52780:4000::/202780:4fff:ffff:ffff:ffff:ffff:ffff:ffff
62780:5000::/202780:5fff:ffff:ffff:ffff:ffff:ffff:ffff
72780:6000::/202780:6fff:ffff:ffff:ffff:ffff:ffff:ffff
82780:7000::/202780:7fff:ffff:ffff:ffff:ffff:ffff:ffff
92780:8000::/202780:8fff:ffff:ffff:ffff:ffff:ffff:ffff
102780:9000::/202780:9fff:ffff:ffff:ffff:ffff:ffff:ffff
112780:a000::/202780:afff:ffff:ffff:ffff:ffff:ffff:ffff
122780:b000::/202780:bfff:ffff:ffff:ffff:ffff:ffff:ffff
132780:c000::/202780:cfff:ffff:ffff:ffff:ffff:ffff:ffff
142780:d000::/202780:dfff:ffff:ffff:ffff:ffff:ffff:ffff
152780:e000::/202780:efff:ffff:ffff:ffff:ffff:ffff:ffff
162780:f000::/202780:ffff:ffff:ffff:ffff:ffff:ffff:ffff
172781::/202781:fff:ffff:ffff:ffff:ffff:ffff:ffff
182781:1000::/202781:1fff:ffff:ffff:ffff:ffff:ffff:ffff
192781:2000::/202781:2fff:ffff:ffff:ffff:ffff:ffff:ffff
202781:3000::/202781:3fff:ffff:ffff:ffff:ffff:ffff:ffff
212781:4000::/202781:4fff:ffff:ffff:ffff:ffff:ffff:ffff
222781:5000::/202781:5fff:ffff:ffff:ffff:ffff:ffff:ffff
232781:6000::/202781:6fff:ffff:ffff:ffff:ffff:ffff:ffff
242781:7000::/202781:7fff:ffff:ffff:ffff:ffff:ffff:ffff
252781:8000::/202781:8fff:ffff:ffff:ffff:ffff:ffff:ffff
262781:9000::/202781:9fff:ffff:ffff:ffff:ffff:ffff:ffff
272781:a000::/202781:afff:ffff:ffff:ffff:ffff:ffff:ffff
282781:b000::/202781:bfff:ffff:ffff:ffff:ffff:ffff:ffff
292781:c000::/202781:cfff:ffff:ffff:ffff:ffff:ffff:ffff
302781:d000::/202781:dfff:ffff:ffff:ffff:ffff:ffff:ffff
312781:e000::/202781:efff:ffff:ffff:ffff:ffff:ffff:ffff
322781:f000::/202781:ffff:ffff:ffff:ffff:ffff:ffff:ffff
332782::/202782:fff:ffff:ffff:ffff:ffff:ffff:ffff
342782:1000::/202782:1fff:ffff:ffff:ffff:ffff:ffff:ffff
352782:2000::/202782:2fff:ffff:ffff:ffff:ffff:ffff:ffff
362782:3000::/202782:3fff:ffff:ffff:ffff:ffff:ffff:ffff
372782:4000::/202782:4fff:ffff:ffff:ffff:ffff:ffff:ffff
382782:5000::/202782:5fff:ffff:ffff:ffff:ffff:ffff:ffff
392782:6000::/202782:6fff:ffff:ffff:ffff:ffff:ffff:ffff
402782:7000::/202782:7fff:ffff:ffff:ffff:ffff:ffff:ffff
412782:8000::/202782:8fff:ffff:ffff:ffff:ffff:ffff:ffff
422782:9000::/202782:9fff:ffff:ffff:ffff:ffff:ffff:ffff
432782:a000::/202782:afff:ffff:ffff:ffff:ffff:ffff:ffff
442782:b000::/202782:bfff:ffff:ffff:ffff:ffff:ffff:ffff
452782:c000::/202782:cfff:ffff:ffff:ffff:ffff:ffff:ffff
462782:d000::/202782:dfff:ffff:ffff:ffff:ffff:ffff:ffff
472782:e000::/202782:efff:ffff:ffff:ffff:ffff:ffff:ffff
482782:f000::/202782:ffff:ffff:ffff:ffff:ffff:ffff:ffff
492783::/202783:fff:ffff:ffff:ffff:ffff:ffff:ffff
502783:1000::/202783:1fff:ffff:ffff:ffff:ffff:ffff:ffff
512783:2000::/202783:2fff:ffff:ffff:ffff:ffff:ffff:ffff
522783:3000::/202783:3fff:ffff:ffff:ffff:ffff:ffff:ffff
532783:4000::/202783:4fff:ffff:ffff:ffff:ffff:ffff:ffff
542783:5000::/202783:5fff:ffff:ffff:ffff:ffff:ffff:ffff
552783:6000::/202783:6fff:ffff:ffff:ffff:ffff:ffff:ffff
562783:7000::/202783:7fff:ffff:ffff:ffff:ffff:ffff:ffff
572783:8000::/202783:8fff:ffff:ffff:ffff:ffff:ffff:ffff
582783:9000::/202783:9fff:ffff:ffff:ffff:ffff:ffff:ffff
592783:a000::/202783:afff:ffff:ffff:ffff:ffff:ffff:ffff
602783:b000::/202783:bfff:ffff:ffff:ffff:ffff:ffff:ffff
612783:c000::/202783:cfff:ffff:ffff:ffff:ffff:ffff:ffff
622783:d000::/202783:dfff:ffff:ffff:ffff:ffff:ffff:ffff
632783:e000::/202783:efff:ffff:ffff:ffff:ffff:ffff:ffff
642783:f000::/202783:ffff:ffff:ffff:ffff:ffff:ffff:ffff
652784::/202784:fff:ffff:ffff:ffff:ffff:ffff:ffff
662784:1000::/202784:1fff:ffff:ffff:ffff:ffff:ffff:ffff
672784:2000::/202784:2fff:ffff:ffff:ffff:ffff:ffff:ffff
682784:3000::/202784:3fff:ffff:ffff:ffff:ffff:ffff:ffff
692784:4000::/202784:4fff:ffff:ffff:ffff:ffff:ffff:ffff
702784:5000::/202784:5fff:ffff:ffff:ffff:ffff:ffff:ffff
712784:6000::/202784:6fff:ffff:ffff:ffff:ffff:ffff:ffff
722784:7000::/202784:7fff:ffff:ffff:ffff:ffff:ffff:ffff
732784:8000::/202784:8fff:ffff:ffff:ffff:ffff:ffff:ffff
742784:9000::/202784:9fff:ffff:ffff:ffff:ffff:ffff:ffff
752784:a000::/202784:afff:ffff:ffff:ffff:ffff:ffff:ffff
762784:b000::/202784:bfff:ffff:ffff:ffff:ffff:ffff:ffff
772784:c000::/202784:cfff:ffff:ffff:ffff:ffff:ffff:ffff
782784:d000::/202784:dfff:ffff:ffff:ffff:ffff:ffff:ffff
792784:e000::/202784:efff:ffff:ffff:ffff:ffff:ffff:ffff
802784:f000::/202784:ffff:ffff:ffff:ffff:ffff:ffff:ffff
812785::/202785:fff:ffff:ffff:ffff:ffff:ffff:ffff
822785:1000::/202785:1fff:ffff:ffff:ffff:ffff:ffff:ffff
832785:2000::/202785:2fff:ffff:ffff:ffff:ffff:ffff:ffff
842785:3000::/202785:3fff:ffff:ffff:ffff:ffff:ffff:ffff
852785:4000::/202785:4fff:ffff:ffff:ffff:ffff:ffff:ffff
862785:5000::/202785:5fff:ffff:ffff:ffff:ffff:ffff:ffff
872785:6000::/202785:6fff:ffff:ffff:ffff:ffff:ffff:ffff
882785:7000::/202785:7fff:ffff:ffff:ffff:ffff:ffff:ffff
892785:8000::/202785:8fff:ffff:ffff:ffff:ffff:ffff:ffff
902785:9000::/202785:9fff:ffff:ffff:ffff:ffff:ffff:ffff
912785:a000::/202785:afff:ffff:ffff:ffff:ffff:ffff:ffff
922785:b000::/202785:bfff:ffff:ffff:ffff:ffff:ffff:ffff
932785:c000::/202785:cfff:ffff:ffff:ffff:ffff:ffff:ffff
942785:d000::/202785:dfff:ffff:ffff:ffff:ffff:ffff:ffff
952785:e000::/202785:efff:ffff:ffff:ffff:ffff:ffff:ffff
962785:f000::/202785:ffff:ffff:ffff:ffff:ffff:ffff:ffff
972786::/202786:fff:ffff:ffff:ffff:ffff:ffff:ffff
982786:1000::/202786:1fff:ffff:ffff:ffff:ffff:ffff:ffff
992786:2000::/202786:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1002786:3000::/202786:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1012786:4000::/202786:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1022786:5000::/202786:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1032786:6000::/202786:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1042786:7000::/202786:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1052786:8000::/202786:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1062786:9000::/202786:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1072786:a000::/202786:afff:ffff:ffff:ffff:ffff:ffff:ffff
1082786:b000::/202786:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1092786:c000::/202786:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1102786:d000::/202786:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1112786:e000::/202786:efff:ffff:ffff:ffff:ffff:ffff:ffff
1122786:f000::/202786:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1132787::/202787:fff:ffff:ffff:ffff:ffff:ffff:ffff
1142787:1000::/202787:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1152787:2000::/202787:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1162787:3000::/202787:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1172787:4000::/202787:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1182787:5000::/202787:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1192787:6000::/202787:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1202787:7000::/202787:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1212787:8000::/202787:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1222787:9000::/202787:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1232787:a000::/202787:afff:ffff:ffff:ffff:ffff:ffff:ffff
1242787:b000::/202787:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1252787:c000::/202787:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1262787:d000::/202787:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1272787:e000::/202787:efff:ffff:ffff:ffff:ffff:ffff:ffff
1282787:f000::/202787:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1292788::/202788:fff:ffff:ffff:ffff:ffff:ffff:ffff
1302788:1000::/202788:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1312788:2000::/202788:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1322788:3000::/202788:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1332788:4000::/202788:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1342788:5000::/202788:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1352788:6000::/202788:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1362788:7000::/202788:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1372788:8000::/202788:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1382788:9000::/202788:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1392788:a000::/202788:afff:ffff:ffff:ffff:ffff:ffff:ffff
1402788:b000::/202788:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1412788:c000::/202788:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1422788:d000::/202788:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1432788:e000::/202788:efff:ffff:ffff:ffff:ffff:ffff:ffff
1442788:f000::/202788:ffff:ffff:ffff:ffff:ffff:ffff:ffff
1452789::/202789:fff:ffff:ffff:ffff:ffff:ffff:ffff
1462789:1000::/202789:1fff:ffff:ffff:ffff:ffff:ffff:ffff
1472789:2000::/202789:2fff:ffff:ffff:ffff:ffff:ffff:ffff
1482789:3000::/202789:3fff:ffff:ffff:ffff:ffff:ffff:ffff
1492789:4000::/202789:4fff:ffff:ffff:ffff:ffff:ffff:ffff
1502789:5000::/202789:5fff:ffff:ffff:ffff:ffff:ffff:ffff
1512789:6000::/202789:6fff:ffff:ffff:ffff:ffff:ffff:ffff
1522789:7000::/202789:7fff:ffff:ffff:ffff:ffff:ffff:ffff
1532789:8000::/202789:8fff:ffff:ffff:ffff:ffff:ffff:ffff
1542789:9000::/202789:9fff:ffff:ffff:ffff:ffff:ffff:ffff
1552789:a000::/202789:afff:ffff:ffff:ffff:ffff:ffff:ffff
1562789:b000::/202789:bfff:ffff:ffff:ffff:ffff:ffff:ffff
1572789:c000::/202789:cfff:ffff:ffff:ffff:ffff:ffff:ffff
1582789:d000::/202789:dfff:ffff:ffff:ffff:ffff:ffff:ffff
1592789:e000::/202789:efff:ffff:ffff:ffff:ffff:ffff:ffff
1602789:f000::/202789:ffff:ffff:ffff:ffff:ffff:ffff:ffff
161278a::/20278a:fff:ffff:ffff:ffff:ffff:ffff:ffff
162278a:1000::/20278a:1fff:ffff:ffff:ffff:ffff:ffff:ffff
163278a:2000::/20278a:2fff:ffff:ffff:ffff:ffff:ffff:ffff
164278a:3000::/20278a:3fff:ffff:ffff:ffff:ffff:ffff:ffff
165278a:4000::/20278a:4fff:ffff:ffff:ffff:ffff:ffff:ffff
166278a:5000::/20278a:5fff:ffff:ffff:ffff:ffff:ffff:ffff
167278a:6000::/20278a:6fff:ffff:ffff:ffff:ffff:ffff:ffff
168278a:7000::/20278a:7fff:ffff:ffff:ffff:ffff:ffff:ffff
169278a:8000::/20278a:8fff:ffff:ffff:ffff:ffff:ffff:ffff
170278a:9000::/20278a:9fff:ffff:ffff:ffff:ffff:ffff:ffff
171278a:a000::/20278a:afff:ffff:ffff:ffff:ffff:ffff:ffff
172278a:b000::/20278a:bfff:ffff:ffff:ffff:ffff:ffff:ffff
173278a:c000::/20278a:cfff:ffff:ffff:ffff:ffff:ffff:ffff
174278a:d000::/20278a:dfff:ffff:ffff:ffff:ffff:ffff:ffff
175278a:e000::/20278a:efff:ffff:ffff:ffff:ffff:ffff:ffff
176278a:f000::/20278a:ffff:ffff:ffff:ffff:ffff:ffff:ffff
177278b::/20278b:fff:ffff:ffff:ffff:ffff:ffff:ffff
178278b:1000::/20278b:1fff:ffff:ffff:ffff:ffff:ffff:ffff
179278b:2000::/20278b:2fff:ffff:ffff:ffff:ffff:ffff:ffff
180278b:3000::/20278b:3fff:ffff:ffff:ffff:ffff:ffff:ffff
181278b:4000::/20278b:4fff:ffff:ffff:ffff:ffff:ffff:ffff
182278b:5000::/20278b:5fff:ffff:ffff:ffff:ffff:ffff:ffff
183278b:6000::/20278b:6fff:ffff:ffff:ffff:ffff:ffff:ffff
184278b:7000::/20278b:7fff:ffff:ffff:ffff:ffff:ffff:ffff
185278b:8000::/20278b:8fff:ffff:ffff:ffff:ffff:ffff:ffff
186278b:9000::/20278b:9fff:ffff:ffff:ffff:ffff:ffff:ffff
187278b:a000::/20278b:afff:ffff:ffff:ffff:ffff:ffff:ffff
188278b:b000::/20278b:bfff:ffff:ffff:ffff:ffff:ffff:ffff
189278b:c000::/20278b:cfff:ffff:ffff:ffff:ffff:ffff:ffff
190278b:d000::/20278b:dfff:ffff:ffff:ffff:ffff:ffff:ffff
191278b:e000::/20278b:efff:ffff:ffff:ffff:ffff:ffff:ffff
192278b:f000::/20278b:ffff:ffff:ffff:ffff:ffff:ffff:ffff
193278c::/20278c:fff:ffff:ffff:ffff:ffff:ffff:ffff
194278c:1000::/20278c:1fff:ffff:ffff:ffff:ffff:ffff:ffff
195278c:2000::/20278c:2fff:ffff:ffff:ffff:ffff:ffff:ffff
196278c:3000::/20278c:3fff:ffff:ffff:ffff:ffff:ffff:ffff
197278c:4000::/20278c:4fff:ffff:ffff:ffff:ffff:ffff:ffff
198278c:5000::/20278c:5fff:ffff:ffff:ffff:ffff:ffff:ffff
199278c:6000::/20278c:6fff:ffff:ffff:ffff:ffff:ffff:ffff
200278c:7000::/20278c:7fff:ffff:ffff:ffff:ffff:ffff:ffff
201278c:8000::/20278c:8fff:ffff:ffff:ffff:ffff:ffff:ffff
202278c:9000::/20278c:9fff:ffff:ffff:ffff:ffff:ffff:ffff
203278c:a000::/20278c:afff:ffff:ffff:ffff:ffff:ffff:ffff
204278c:b000::/20278c:bfff:ffff:ffff:ffff:ffff:ffff:ffff
205278c:c000::/20278c:cfff:ffff:ffff:ffff:ffff:ffff:ffff
206278c:d000::/20278c:dfff:ffff:ffff:ffff:ffff:ffff:ffff
207278c:e000::/20278c:efff:ffff:ffff:ffff:ffff:ffff:ffff
208278c:f000::/20278c:ffff:ffff:ffff:ffff:ffff:ffff:ffff
209278d::/20278d:fff:ffff:ffff:ffff:ffff:ffff:ffff
210278d:1000::/20278d:1fff:ffff:ffff:ffff:ffff:ffff:ffff
211278d:2000::/20278d:2fff:ffff:ffff:ffff:ffff:ffff:ffff
212278d:3000::/20278d:3fff:ffff:ffff:ffff:ffff:ffff:ffff
213278d:4000::/20278d:4fff:ffff:ffff:ffff:ffff:ffff:ffff
214278d:5000::/20278d:5fff:ffff:ffff:ffff:ffff:ffff:ffff
215278d:6000::/20278d:6fff:ffff:ffff:ffff:ffff:ffff:ffff
216278d:7000::/20278d:7fff:ffff:ffff:ffff:ffff:ffff:ffff
217278d:8000::/20278d:8fff:ffff:ffff:ffff:ffff:ffff:ffff
218278d:9000::/20278d:9fff:ffff:ffff:ffff:ffff:ffff:ffff
219278d:a000::/20278d:afff:ffff:ffff:ffff:ffff:ffff:ffff
220278d:b000::/20278d:bfff:ffff:ffff:ffff:ffff:ffff:ffff
221278d:c000::/20278d:cfff:ffff:ffff:ffff:ffff:ffff:ffff
222278d:d000::/20278d:dfff:ffff:ffff:ffff:ffff:ffff:ffff
223278d:e000::/20278d:efff:ffff:ffff:ffff:ffff:ffff:ffff
224278d:f000::/20278d:ffff:ffff:ffff:ffff:ffff:ffff:ffff
225278e::/20278e:fff:ffff:ffff:ffff:ffff:ffff:ffff
226278e:1000::/20278e:1fff:ffff:ffff:ffff:ffff:ffff:ffff
227278e:2000::/20278e:2fff:ffff:ffff:ffff:ffff:ffff:ffff
228278e:3000::/20278e:3fff:ffff:ffff:ffff:ffff:ffff:ffff
229278e:4000::/20278e:4fff:ffff:ffff:ffff:ffff:ffff:ffff
230278e:5000::/20278e:5fff:ffff:ffff:ffff:ffff:ffff:ffff
231278e:6000::/20278e:6fff:ffff:ffff:ffff:ffff:ffff:ffff
232278e:7000::/20278e:7fff:ffff:ffff:ffff:ffff:ffff:ffff
233278e:8000::/20278e:8fff:ffff:ffff:ffff:ffff:ffff:ffff
234278e:9000::/20278e:9fff:ffff:ffff:ffff:ffff:ffff:ffff
235278e:a000::/20278e:afff:ffff:ffff:ffff:ffff:ffff:ffff
236278e:b000::/20278e:bfff:ffff:ffff:ffff:ffff:ffff:ffff
237278e:c000::/20278e:cfff:ffff:ffff:ffff:ffff:ffff:ffff
238278e:d000::/20278e:dfff:ffff:ffff:ffff:ffff:ffff:ffff
239278e:e000::/20278e:efff:ffff:ffff:ffff:ffff:ffff:ffff
240278e:f000::/20278e:ffff:ffff:ffff:ffff:ffff:ffff:ffff
241278f::/20278f:fff:ffff:ffff:ffff:ffff:ffff:ffff
242278f:1000::/20278f:1fff:ffff:ffff:ffff:ffff:ffff:ffff
243278f:2000::/20278f:2fff:ffff:ffff:ffff:ffff:ffff:ffff
244278f:3000::/20278f:3fff:ffff:ffff:ffff:ffff:ffff:ffff
245278f:4000::/20278f:4fff:ffff:ffff:ffff:ffff:ffff:ffff
246278f:5000::/20278f:5fff:ffff:ffff:ffff:ffff:ffff:ffff
247278f:6000::/20278f:6fff:ffff:ffff:ffff:ffff:ffff:ffff
248278f:7000::/20278f:7fff:ffff:ffff:ffff:ffff:ffff:ffff
249278f:8000::/20278f:8fff:ffff:ffff:ffff:ffff:ffff:ffff
250278f:9000::/20278f:9fff:ffff:ffff:ffff:ffff:ffff:ffff
251278f:a000::/20278f:afff:ffff:ffff:ffff:ffff:ffff:ffff
252278f:b000::/20278f:bfff:ffff:ffff:ffff:ffff:ffff:ffff
253278f:c000::/20278f:cfff:ffff:ffff:ffff:ffff:ffff:ffff
254278f:d000::/20278f:dfff:ffff:ffff:ffff:ffff:ffff:ffff
255278f:e000::/20278f:efff:ffff:ffff:ffff:ffff:ffff:ffff
256278f:f000::/20278f: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.