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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/120
Addresses256
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25b:d00a:a800/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:a800
Last address
2c19:dd:d9:dd:c25:c25b:d00a:a8ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:a800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.a.a.0.0.d.b.5.2.c.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25b:d00a:a800/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:a800/1282c19:dd:d9:dd:c25:c25b:d00a:a800
22c19:dd:d9:dd:c25:c25b:d00a:a801/1282c19:dd:d9:dd:c25:c25b:d00a:a801
32c19:dd:d9:dd:c25:c25b:d00a:a802/1282c19:dd:d9:dd:c25:c25b:d00a:a802
42c19:dd:d9:dd:c25:c25b:d00a:a803/1282c19:dd:d9:dd:c25:c25b:d00a:a803
52c19:dd:d9:dd:c25:c25b:d00a:a804/1282c19:dd:d9:dd:c25:c25b:d00a:a804
62c19:dd:d9:dd:c25:c25b:d00a:a805/1282c19:dd:d9:dd:c25:c25b:d00a:a805
72c19:dd:d9:dd:c25:c25b:d00a:a806/1282c19:dd:d9:dd:c25:c25b:d00a:a806
82c19:dd:d9:dd:c25:c25b:d00a:a807/1282c19:dd:d9:dd:c25:c25b:d00a:a807
92c19:dd:d9:dd:c25:c25b:d00a:a808/1282c19:dd:d9:dd:c25:c25b:d00a:a808
102c19:dd:d9:dd:c25:c25b:d00a:a809/1282c19:dd:d9:dd:c25:c25b:d00a:a809
112c19:dd:d9:dd:c25:c25b:d00a:a80a/1282c19:dd:d9:dd:c25:c25b:d00a:a80a
122c19:dd:d9:dd:c25:c25b:d00a:a80b/1282c19:dd:d9:dd:c25:c25b:d00a:a80b
132c19:dd:d9:dd:c25:c25b:d00a:a80c/1282c19:dd:d9:dd:c25:c25b:d00a:a80c
142c19:dd:d9:dd:c25:c25b:d00a:a80d/1282c19:dd:d9:dd:c25:c25b:d00a:a80d
152c19:dd:d9:dd:c25:c25b:d00a:a80e/1282c19:dd:d9:dd:c25:c25b:d00a:a80e
162c19:dd:d9:dd:c25:c25b:d00a:a80f/1282c19:dd:d9:dd:c25:c25b:d00a:a80f
172c19:dd:d9:dd:c25:c25b:d00a:a810/1282c19:dd:d9:dd:c25:c25b:d00a:a810
182c19:dd:d9:dd:c25:c25b:d00a:a811/1282c19:dd:d9:dd:c25:c25b:d00a:a811
192c19:dd:d9:dd:c25:c25b:d00a:a812/1282c19:dd:d9:dd:c25:c25b:d00a:a812
202c19:dd:d9:dd:c25:c25b:d00a:a813/1282c19:dd:d9:dd:c25:c25b:d00a:a813
212c19:dd:d9:dd:c25:c25b:d00a:a814/1282c19:dd:d9:dd:c25:c25b:d00a:a814
222c19:dd:d9:dd:c25:c25b:d00a:a815/1282c19:dd:d9:dd:c25:c25b:d00a:a815
232c19:dd:d9:dd:c25:c25b:d00a:a816/1282c19:dd:d9:dd:c25:c25b:d00a:a816
242c19:dd:d9:dd:c25:c25b:d00a:a817/1282c19:dd:d9:dd:c25:c25b:d00a:a817
252c19:dd:d9:dd:c25:c25b:d00a:a818/1282c19:dd:d9:dd:c25:c25b:d00a:a818
262c19:dd:d9:dd:c25:c25b:d00a:a819/1282c19:dd:d9:dd:c25:c25b:d00a:a819
272c19:dd:d9:dd:c25:c25b:d00a:a81a/1282c19:dd:d9:dd:c25:c25b:d00a:a81a
282c19:dd:d9:dd:c25:c25b:d00a:a81b/1282c19:dd:d9:dd:c25:c25b:d00a:a81b
292c19:dd:d9:dd:c25:c25b:d00a:a81c/1282c19:dd:d9:dd:c25:c25b:d00a:a81c
302c19:dd:d9:dd:c25:c25b:d00a:a81d/1282c19:dd:d9:dd:c25:c25b:d00a:a81d
312c19:dd:d9:dd:c25:c25b:d00a:a81e/1282c19:dd:d9:dd:c25:c25b:d00a:a81e
322c19:dd:d9:dd:c25:c25b:d00a:a81f/1282c19:dd:d9:dd:c25:c25b:d00a:a81f
332c19:dd:d9:dd:c25:c25b:d00a:a820/1282c19:dd:d9:dd:c25:c25b:d00a:a820
342c19:dd:d9:dd:c25:c25b:d00a:a821/1282c19:dd:d9:dd:c25:c25b:d00a:a821
352c19:dd:d9:dd:c25:c25b:d00a:a822/1282c19:dd:d9:dd:c25:c25b:d00a:a822
362c19:dd:d9:dd:c25:c25b:d00a:a823/1282c19:dd:d9:dd:c25:c25b:d00a:a823
372c19:dd:d9:dd:c25:c25b:d00a:a824/1282c19:dd:d9:dd:c25:c25b:d00a:a824
382c19:dd:d9:dd:c25:c25b:d00a:a825/1282c19:dd:d9:dd:c25:c25b:d00a:a825
392c19:dd:d9:dd:c25:c25b:d00a:a826/1282c19:dd:d9:dd:c25:c25b:d00a:a826
402c19:dd:d9:dd:c25:c25b:d00a:a827/1282c19:dd:d9:dd:c25:c25b:d00a:a827
412c19:dd:d9:dd:c25:c25b:d00a:a828/1282c19:dd:d9:dd:c25:c25b:d00a:a828
422c19:dd:d9:dd:c25:c25b:d00a:a829/1282c19:dd:d9:dd:c25:c25b:d00a:a829
432c19:dd:d9:dd:c25:c25b:d00a:a82a/1282c19:dd:d9:dd:c25:c25b:d00a:a82a
442c19:dd:d9:dd:c25:c25b:d00a:a82b/1282c19:dd:d9:dd:c25:c25b:d00a:a82b
452c19:dd:d9:dd:c25:c25b:d00a:a82c/1282c19:dd:d9:dd:c25:c25b:d00a:a82c
462c19:dd:d9:dd:c25:c25b:d00a:a82d/1282c19:dd:d9:dd:c25:c25b:d00a:a82d
472c19:dd:d9:dd:c25:c25b:d00a:a82e/1282c19:dd:d9:dd:c25:c25b:d00a:a82e
482c19:dd:d9:dd:c25:c25b:d00a:a82f/1282c19:dd:d9:dd:c25:c25b:d00a:a82f
492c19:dd:d9:dd:c25:c25b:d00a:a830/1282c19:dd:d9:dd:c25:c25b:d00a:a830
502c19:dd:d9:dd:c25:c25b:d00a:a831/1282c19:dd:d9:dd:c25:c25b:d00a:a831
512c19:dd:d9:dd:c25:c25b:d00a:a832/1282c19:dd:d9:dd:c25:c25b:d00a:a832
522c19:dd:d9:dd:c25:c25b:d00a:a833/1282c19:dd:d9:dd:c25:c25b:d00a:a833
532c19:dd:d9:dd:c25:c25b:d00a:a834/1282c19:dd:d9:dd:c25:c25b:d00a:a834
542c19:dd:d9:dd:c25:c25b:d00a:a835/1282c19:dd:d9:dd:c25:c25b:d00a:a835
552c19:dd:d9:dd:c25:c25b:d00a:a836/1282c19:dd:d9:dd:c25:c25b:d00a:a836
562c19:dd:d9:dd:c25:c25b:d00a:a837/1282c19:dd:d9:dd:c25:c25b:d00a:a837
572c19:dd:d9:dd:c25:c25b:d00a:a838/1282c19:dd:d9:dd:c25:c25b:d00a:a838
582c19:dd:d9:dd:c25:c25b:d00a:a839/1282c19:dd:d9:dd:c25:c25b:d00a:a839
592c19:dd:d9:dd:c25:c25b:d00a:a83a/1282c19:dd:d9:dd:c25:c25b:d00a:a83a
602c19:dd:d9:dd:c25:c25b:d00a:a83b/1282c19:dd:d9:dd:c25:c25b:d00a:a83b
612c19:dd:d9:dd:c25:c25b:d00a:a83c/1282c19:dd:d9:dd:c25:c25b:d00a:a83c
622c19:dd:d9:dd:c25:c25b:d00a:a83d/1282c19:dd:d9:dd:c25:c25b:d00a:a83d
632c19:dd:d9:dd:c25:c25b:d00a:a83e/1282c19:dd:d9:dd:c25:c25b:d00a:a83e
642c19:dd:d9:dd:c25:c25b:d00a:a83f/1282c19:dd:d9:dd:c25:c25b:d00a:a83f
652c19:dd:d9:dd:c25:c25b:d00a:a840/1282c19:dd:d9:dd:c25:c25b:d00a:a840
662c19:dd:d9:dd:c25:c25b:d00a:a841/1282c19:dd:d9:dd:c25:c25b:d00a:a841
672c19:dd:d9:dd:c25:c25b:d00a:a842/1282c19:dd:d9:dd:c25:c25b:d00a:a842
682c19:dd:d9:dd:c25:c25b:d00a:a843/1282c19:dd:d9:dd:c25:c25b:d00a:a843
692c19:dd:d9:dd:c25:c25b:d00a:a844/1282c19:dd:d9:dd:c25:c25b:d00a:a844
702c19:dd:d9:dd:c25:c25b:d00a:a845/1282c19:dd:d9:dd:c25:c25b:d00a:a845
712c19:dd:d9:dd:c25:c25b:d00a:a846/1282c19:dd:d9:dd:c25:c25b:d00a:a846
722c19:dd:d9:dd:c25:c25b:d00a:a847/1282c19:dd:d9:dd:c25:c25b:d00a:a847
732c19:dd:d9:dd:c25:c25b:d00a:a848/1282c19:dd:d9:dd:c25:c25b:d00a:a848
742c19:dd:d9:dd:c25:c25b:d00a:a849/1282c19:dd:d9:dd:c25:c25b:d00a:a849
752c19:dd:d9:dd:c25:c25b:d00a:a84a/1282c19:dd:d9:dd:c25:c25b:d00a:a84a
762c19:dd:d9:dd:c25:c25b:d00a:a84b/1282c19:dd:d9:dd:c25:c25b:d00a:a84b
772c19:dd:d9:dd:c25:c25b:d00a:a84c/1282c19:dd:d9:dd:c25:c25b:d00a:a84c
782c19:dd:d9:dd:c25:c25b:d00a:a84d/1282c19:dd:d9:dd:c25:c25b:d00a:a84d
792c19:dd:d9:dd:c25:c25b:d00a:a84e/1282c19:dd:d9:dd:c25:c25b:d00a:a84e
802c19:dd:d9:dd:c25:c25b:d00a:a84f/1282c19:dd:d9:dd:c25:c25b:d00a:a84f
812c19:dd:d9:dd:c25:c25b:d00a:a850/1282c19:dd:d9:dd:c25:c25b:d00a:a850
822c19:dd:d9:dd:c25:c25b:d00a:a851/1282c19:dd:d9:dd:c25:c25b:d00a:a851
832c19:dd:d9:dd:c25:c25b:d00a:a852/1282c19:dd:d9:dd:c25:c25b:d00a:a852
842c19:dd:d9:dd:c25:c25b:d00a:a853/1282c19:dd:d9:dd:c25:c25b:d00a:a853
852c19:dd:d9:dd:c25:c25b:d00a:a854/1282c19:dd:d9:dd:c25:c25b:d00a:a854
862c19:dd:d9:dd:c25:c25b:d00a:a855/1282c19:dd:d9:dd:c25:c25b:d00a:a855
872c19:dd:d9:dd:c25:c25b:d00a:a856/1282c19:dd:d9:dd:c25:c25b:d00a:a856
882c19:dd:d9:dd:c25:c25b:d00a:a857/1282c19:dd:d9:dd:c25:c25b:d00a:a857
892c19:dd:d9:dd:c25:c25b:d00a:a858/1282c19:dd:d9:dd:c25:c25b:d00a:a858
902c19:dd:d9:dd:c25:c25b:d00a:a859/1282c19:dd:d9:dd:c25:c25b:d00a:a859
912c19:dd:d9:dd:c25:c25b:d00a:a85a/1282c19:dd:d9:dd:c25:c25b:d00a:a85a
922c19:dd:d9:dd:c25:c25b:d00a:a85b/1282c19:dd:d9:dd:c25:c25b:d00a:a85b
932c19:dd:d9:dd:c25:c25b:d00a:a85c/1282c19:dd:d9:dd:c25:c25b:d00a:a85c
942c19:dd:d9:dd:c25:c25b:d00a:a85d/1282c19:dd:d9:dd:c25:c25b:d00a:a85d
952c19:dd:d9:dd:c25:c25b:d00a:a85e/1282c19:dd:d9:dd:c25:c25b:d00a:a85e
962c19:dd:d9:dd:c25:c25b:d00a:a85f/1282c19:dd:d9:dd:c25:c25b:d00a:a85f
972c19:dd:d9:dd:c25:c25b:d00a:a860/1282c19:dd:d9:dd:c25:c25b:d00a:a860
982c19:dd:d9:dd:c25:c25b:d00a:a861/1282c19:dd:d9:dd:c25:c25b:d00a:a861
992c19:dd:d9:dd:c25:c25b:d00a:a862/1282c19:dd:d9:dd:c25:c25b:d00a:a862
1002c19:dd:d9:dd:c25:c25b:d00a:a863/1282c19:dd:d9:dd:c25:c25b:d00a:a863
1012c19:dd:d9:dd:c25:c25b:d00a:a864/1282c19:dd:d9:dd:c25:c25b:d00a:a864
1022c19:dd:d9:dd:c25:c25b:d00a:a865/1282c19:dd:d9:dd:c25:c25b:d00a:a865
1032c19:dd:d9:dd:c25:c25b:d00a:a866/1282c19:dd:d9:dd:c25:c25b:d00a:a866
1042c19:dd:d9:dd:c25:c25b:d00a:a867/1282c19:dd:d9:dd:c25:c25b:d00a:a867
1052c19:dd:d9:dd:c25:c25b:d00a:a868/1282c19:dd:d9:dd:c25:c25b:d00a:a868
1062c19:dd:d9:dd:c25:c25b:d00a:a869/1282c19:dd:d9:dd:c25:c25b:d00a:a869
1072c19:dd:d9:dd:c25:c25b:d00a:a86a/1282c19:dd:d9:dd:c25:c25b:d00a:a86a
1082c19:dd:d9:dd:c25:c25b:d00a:a86b/1282c19:dd:d9:dd:c25:c25b:d00a:a86b
1092c19:dd:d9:dd:c25:c25b:d00a:a86c/1282c19:dd:d9:dd:c25:c25b:d00a:a86c
1102c19:dd:d9:dd:c25:c25b:d00a:a86d/1282c19:dd:d9:dd:c25:c25b:d00a:a86d
1112c19:dd:d9:dd:c25:c25b:d00a:a86e/1282c19:dd:d9:dd:c25:c25b:d00a:a86e
1122c19:dd:d9:dd:c25:c25b:d00a:a86f/1282c19:dd:d9:dd:c25:c25b:d00a:a86f
1132c19:dd:d9:dd:c25:c25b:d00a:a870/1282c19:dd:d9:dd:c25:c25b:d00a:a870
1142c19:dd:d9:dd:c25:c25b:d00a:a871/1282c19:dd:d9:dd:c25:c25b:d00a:a871
1152c19:dd:d9:dd:c25:c25b:d00a:a872/1282c19:dd:d9:dd:c25:c25b:d00a:a872
1162c19:dd:d9:dd:c25:c25b:d00a:a873/1282c19:dd:d9:dd:c25:c25b:d00a:a873
1172c19:dd:d9:dd:c25:c25b:d00a:a874/1282c19:dd:d9:dd:c25:c25b:d00a:a874
1182c19:dd:d9:dd:c25:c25b:d00a:a875/1282c19:dd:d9:dd:c25:c25b:d00a:a875
1192c19:dd:d9:dd:c25:c25b:d00a:a876/1282c19:dd:d9:dd:c25:c25b:d00a:a876
1202c19:dd:d9:dd:c25:c25b:d00a:a877/1282c19:dd:d9:dd:c25:c25b:d00a:a877
1212c19:dd:d9:dd:c25:c25b:d00a:a878/1282c19:dd:d9:dd:c25:c25b:d00a:a878
1222c19:dd:d9:dd:c25:c25b:d00a:a879/1282c19:dd:d9:dd:c25:c25b:d00a:a879
1232c19:dd:d9:dd:c25:c25b:d00a:a87a/1282c19:dd:d9:dd:c25:c25b:d00a:a87a
1242c19:dd:d9:dd:c25:c25b:d00a:a87b/1282c19:dd:d9:dd:c25:c25b:d00a:a87b
1252c19:dd:d9:dd:c25:c25b:d00a:a87c/1282c19:dd:d9:dd:c25:c25b:d00a:a87c
1262c19:dd:d9:dd:c25:c25b:d00a:a87d/1282c19:dd:d9:dd:c25:c25b:d00a:a87d
1272c19:dd:d9:dd:c25:c25b:d00a:a87e/1282c19:dd:d9:dd:c25:c25b:d00a:a87e
1282c19:dd:d9:dd:c25:c25b:d00a:a87f/1282c19:dd:d9:dd:c25:c25b:d00a:a87f
1292c19:dd:d9:dd:c25:c25b:d00a:a880/1282c19:dd:d9:dd:c25:c25b:d00a:a880
1302c19:dd:d9:dd:c25:c25b:d00a:a881/1282c19:dd:d9:dd:c25:c25b:d00a:a881
1312c19:dd:d9:dd:c25:c25b:d00a:a882/1282c19:dd:d9:dd:c25:c25b:d00a:a882
1322c19:dd:d9:dd:c25:c25b:d00a:a883/1282c19:dd:d9:dd:c25:c25b:d00a:a883
1332c19:dd:d9:dd:c25:c25b:d00a:a884/1282c19:dd:d9:dd:c25:c25b:d00a:a884
1342c19:dd:d9:dd:c25:c25b:d00a:a885/1282c19:dd:d9:dd:c25:c25b:d00a:a885
1352c19:dd:d9:dd:c25:c25b:d00a:a886/1282c19:dd:d9:dd:c25:c25b:d00a:a886
1362c19:dd:d9:dd:c25:c25b:d00a:a887/1282c19:dd:d9:dd:c25:c25b:d00a:a887
1372c19:dd:d9:dd:c25:c25b:d00a:a888/1282c19:dd:d9:dd:c25:c25b:d00a:a888
1382c19:dd:d9:dd:c25:c25b:d00a:a889/1282c19:dd:d9:dd:c25:c25b:d00a:a889
1392c19:dd:d9:dd:c25:c25b:d00a:a88a/1282c19:dd:d9:dd:c25:c25b:d00a:a88a
1402c19:dd:d9:dd:c25:c25b:d00a:a88b/1282c19:dd:d9:dd:c25:c25b:d00a:a88b
1412c19:dd:d9:dd:c25:c25b:d00a:a88c/1282c19:dd:d9:dd:c25:c25b:d00a:a88c
1422c19:dd:d9:dd:c25:c25b:d00a:a88d/1282c19:dd:d9:dd:c25:c25b:d00a:a88d
1432c19:dd:d9:dd:c25:c25b:d00a:a88e/1282c19:dd:d9:dd:c25:c25b:d00a:a88e
1442c19:dd:d9:dd:c25:c25b:d00a:a88f/1282c19:dd:d9:dd:c25:c25b:d00a:a88f
1452c19:dd:d9:dd:c25:c25b:d00a:a890/1282c19:dd:d9:dd:c25:c25b:d00a:a890
1462c19:dd:d9:dd:c25:c25b:d00a:a891/1282c19:dd:d9:dd:c25:c25b:d00a:a891
1472c19:dd:d9:dd:c25:c25b:d00a:a892/1282c19:dd:d9:dd:c25:c25b:d00a:a892
1482c19:dd:d9:dd:c25:c25b:d00a:a893/1282c19:dd:d9:dd:c25:c25b:d00a:a893
1492c19:dd:d9:dd:c25:c25b:d00a:a894/1282c19:dd:d9:dd:c25:c25b:d00a:a894
1502c19:dd:d9:dd:c25:c25b:d00a:a895/1282c19:dd:d9:dd:c25:c25b:d00a:a895
1512c19:dd:d9:dd:c25:c25b:d00a:a896/1282c19:dd:d9:dd:c25:c25b:d00a:a896
1522c19:dd:d9:dd:c25:c25b:d00a:a897/1282c19:dd:d9:dd:c25:c25b:d00a:a897
1532c19:dd:d9:dd:c25:c25b:d00a:a898/1282c19:dd:d9:dd:c25:c25b:d00a:a898
1542c19:dd:d9:dd:c25:c25b:d00a:a899/1282c19:dd:d9:dd:c25:c25b:d00a:a899
1552c19:dd:d9:dd:c25:c25b:d00a:a89a/1282c19:dd:d9:dd:c25:c25b:d00a:a89a
1562c19:dd:d9:dd:c25:c25b:d00a:a89b/1282c19:dd:d9:dd:c25:c25b:d00a:a89b
1572c19:dd:d9:dd:c25:c25b:d00a:a89c/1282c19:dd:d9:dd:c25:c25b:d00a:a89c
1582c19:dd:d9:dd:c25:c25b:d00a:a89d/1282c19:dd:d9:dd:c25:c25b:d00a:a89d
1592c19:dd:d9:dd:c25:c25b:d00a:a89e/1282c19:dd:d9:dd:c25:c25b:d00a:a89e
1602c19:dd:d9:dd:c25:c25b:d00a:a89f/1282c19:dd:d9:dd:c25:c25b:d00a:a89f
1612c19:dd:d9:dd:c25:c25b:d00a:a8a0/1282c19:dd:d9:dd:c25:c25b:d00a:a8a0
1622c19:dd:d9:dd:c25:c25b:d00a:a8a1/1282c19:dd:d9:dd:c25:c25b:d00a:a8a1
1632c19:dd:d9:dd:c25:c25b:d00a:a8a2/1282c19:dd:d9:dd:c25:c25b:d00a:a8a2
1642c19:dd:d9:dd:c25:c25b:d00a:a8a3/1282c19:dd:d9:dd:c25:c25b:d00a:a8a3
1652c19:dd:d9:dd:c25:c25b:d00a:a8a4/1282c19:dd:d9:dd:c25:c25b:d00a:a8a4
1662c19:dd:d9:dd:c25:c25b:d00a:a8a5/1282c19:dd:d9:dd:c25:c25b:d00a:a8a5
1672c19:dd:d9:dd:c25:c25b:d00a:a8a6/1282c19:dd:d9:dd:c25:c25b:d00a:a8a6
1682c19:dd:d9:dd:c25:c25b:d00a:a8a7/1282c19:dd:d9:dd:c25:c25b:d00a:a8a7
1692c19:dd:d9:dd:c25:c25b:d00a:a8a8/1282c19:dd:d9:dd:c25:c25b:d00a:a8a8
1702c19:dd:d9:dd:c25:c25b:d00a:a8a9/1282c19:dd:d9:dd:c25:c25b:d00a:a8a9
1712c19:dd:d9:dd:c25:c25b:d00a:a8aa/1282c19:dd:d9:dd:c25:c25b:d00a:a8aa
1722c19:dd:d9:dd:c25:c25b:d00a:a8ab/1282c19:dd:d9:dd:c25:c25b:d00a:a8ab
1732c19:dd:d9:dd:c25:c25b:d00a:a8ac/1282c19:dd:d9:dd:c25:c25b:d00a:a8ac
1742c19:dd:d9:dd:c25:c25b:d00a:a8ad/1282c19:dd:d9:dd:c25:c25b:d00a:a8ad
1752c19:dd:d9:dd:c25:c25b:d00a:a8ae/1282c19:dd:d9:dd:c25:c25b:d00a:a8ae
1762c19:dd:d9:dd:c25:c25b:d00a:a8af/1282c19:dd:d9:dd:c25:c25b:d00a:a8af
1772c19:dd:d9:dd:c25:c25b:d00a:a8b0/1282c19:dd:d9:dd:c25:c25b:d00a:a8b0
1782c19:dd:d9:dd:c25:c25b:d00a:a8b1/1282c19:dd:d9:dd:c25:c25b:d00a:a8b1
1792c19:dd:d9:dd:c25:c25b:d00a:a8b2/1282c19:dd:d9:dd:c25:c25b:d00a:a8b2
1802c19:dd:d9:dd:c25:c25b:d00a:a8b3/1282c19:dd:d9:dd:c25:c25b:d00a:a8b3
1812c19:dd:d9:dd:c25:c25b:d00a:a8b4/1282c19:dd:d9:dd:c25:c25b:d00a:a8b4
1822c19:dd:d9:dd:c25:c25b:d00a:a8b5/1282c19:dd:d9:dd:c25:c25b:d00a:a8b5
1832c19:dd:d9:dd:c25:c25b:d00a:a8b6/1282c19:dd:d9:dd:c25:c25b:d00a:a8b6
1842c19:dd:d9:dd:c25:c25b:d00a:a8b7/1282c19:dd:d9:dd:c25:c25b:d00a:a8b7
1852c19:dd:d9:dd:c25:c25b:d00a:a8b8/1282c19:dd:d9:dd:c25:c25b:d00a:a8b8
1862c19:dd:d9:dd:c25:c25b:d00a:a8b9/1282c19:dd:d9:dd:c25:c25b:d00a:a8b9
1872c19:dd:d9:dd:c25:c25b:d00a:a8ba/1282c19:dd:d9:dd:c25:c25b:d00a:a8ba
1882c19:dd:d9:dd:c25:c25b:d00a:a8bb/1282c19:dd:d9:dd:c25:c25b:d00a:a8bb
1892c19:dd:d9:dd:c25:c25b:d00a:a8bc/1282c19:dd:d9:dd:c25:c25b:d00a:a8bc
1902c19:dd:d9:dd:c25:c25b:d00a:a8bd/1282c19:dd:d9:dd:c25:c25b:d00a:a8bd
1912c19:dd:d9:dd:c25:c25b:d00a:a8be/1282c19:dd:d9:dd:c25:c25b:d00a:a8be
1922c19:dd:d9:dd:c25:c25b:d00a:a8bf/1282c19:dd:d9:dd:c25:c25b:d00a:a8bf
1932c19:dd:d9:dd:c25:c25b:d00a:a8c0/1282c19:dd:d9:dd:c25:c25b:d00a:a8c0
1942c19:dd:d9:dd:c25:c25b:d00a:a8c1/1282c19:dd:d9:dd:c25:c25b:d00a:a8c1
1952c19:dd:d9:dd:c25:c25b:d00a:a8c2/1282c19:dd:d9:dd:c25:c25b:d00a:a8c2
1962c19:dd:d9:dd:c25:c25b:d00a:a8c3/1282c19:dd:d9:dd:c25:c25b:d00a:a8c3
1972c19:dd:d9:dd:c25:c25b:d00a:a8c4/1282c19:dd:d9:dd:c25:c25b:d00a:a8c4
1982c19:dd:d9:dd:c25:c25b:d00a:a8c5/1282c19:dd:d9:dd:c25:c25b:d00a:a8c5
1992c19:dd:d9:dd:c25:c25b:d00a:a8c6/1282c19:dd:d9:dd:c25:c25b:d00a:a8c6
2002c19:dd:d9:dd:c25:c25b:d00a:a8c7/1282c19:dd:d9:dd:c25:c25b:d00a:a8c7
2012c19:dd:d9:dd:c25:c25b:d00a:a8c8/1282c19:dd:d9:dd:c25:c25b:d00a:a8c8
2022c19:dd:d9:dd:c25:c25b:d00a:a8c9/1282c19:dd:d9:dd:c25:c25b:d00a:a8c9
2032c19:dd:d9:dd:c25:c25b:d00a:a8ca/1282c19:dd:d9:dd:c25:c25b:d00a:a8ca
2042c19:dd:d9:dd:c25:c25b:d00a:a8cb/1282c19:dd:d9:dd:c25:c25b:d00a:a8cb
2052c19:dd:d9:dd:c25:c25b:d00a:a8cc/1282c19:dd:d9:dd:c25:c25b:d00a:a8cc
2062c19:dd:d9:dd:c25:c25b:d00a:a8cd/1282c19:dd:d9:dd:c25:c25b:d00a:a8cd
2072c19:dd:d9:dd:c25:c25b:d00a:a8ce/1282c19:dd:d9:dd:c25:c25b:d00a:a8ce
2082c19:dd:d9:dd:c25:c25b:d00a:a8cf/1282c19:dd:d9:dd:c25:c25b:d00a:a8cf
2092c19:dd:d9:dd:c25:c25b:d00a:a8d0/1282c19:dd:d9:dd:c25:c25b:d00a:a8d0
2102c19:dd:d9:dd:c25:c25b:d00a:a8d1/1282c19:dd:d9:dd:c25:c25b:d00a:a8d1
2112c19:dd:d9:dd:c25:c25b:d00a:a8d2/1282c19:dd:d9:dd:c25:c25b:d00a:a8d2
2122c19:dd:d9:dd:c25:c25b:d00a:a8d3/1282c19:dd:d9:dd:c25:c25b:d00a:a8d3
2132c19:dd:d9:dd:c25:c25b:d00a:a8d4/1282c19:dd:d9:dd:c25:c25b:d00a:a8d4
2142c19:dd:d9:dd:c25:c25b:d00a:a8d5/1282c19:dd:d9:dd:c25:c25b:d00a:a8d5
2152c19:dd:d9:dd:c25:c25b:d00a:a8d6/1282c19:dd:d9:dd:c25:c25b:d00a:a8d6
2162c19:dd:d9:dd:c25:c25b:d00a:a8d7/1282c19:dd:d9:dd:c25:c25b:d00a:a8d7
2172c19:dd:d9:dd:c25:c25b:d00a:a8d8/1282c19:dd:d9:dd:c25:c25b:d00a:a8d8
2182c19:dd:d9:dd:c25:c25b:d00a:a8d9/1282c19:dd:d9:dd:c25:c25b:d00a:a8d9
2192c19:dd:d9:dd:c25:c25b:d00a:a8da/1282c19:dd:d9:dd:c25:c25b:d00a:a8da
2202c19:dd:d9:dd:c25:c25b:d00a:a8db/1282c19:dd:d9:dd:c25:c25b:d00a:a8db
2212c19:dd:d9:dd:c25:c25b:d00a:a8dc/1282c19:dd:d9:dd:c25:c25b:d00a:a8dc
2222c19:dd:d9:dd:c25:c25b:d00a:a8dd/1282c19:dd:d9:dd:c25:c25b:d00a:a8dd
2232c19:dd:d9:dd:c25:c25b:d00a:a8de/1282c19:dd:d9:dd:c25:c25b:d00a:a8de
2242c19:dd:d9:dd:c25:c25b:d00a:a8df/1282c19:dd:d9:dd:c25:c25b:d00a:a8df
2252c19:dd:d9:dd:c25:c25b:d00a:a8e0/1282c19:dd:d9:dd:c25:c25b:d00a:a8e0
2262c19:dd:d9:dd:c25:c25b:d00a:a8e1/1282c19:dd:d9:dd:c25:c25b:d00a:a8e1
2272c19:dd:d9:dd:c25:c25b:d00a:a8e2/1282c19:dd:d9:dd:c25:c25b:d00a:a8e2
2282c19:dd:d9:dd:c25:c25b:d00a:a8e3/1282c19:dd:d9:dd:c25:c25b:d00a:a8e3
2292c19:dd:d9:dd:c25:c25b:d00a:a8e4/1282c19:dd:d9:dd:c25:c25b:d00a:a8e4
2302c19:dd:d9:dd:c25:c25b:d00a:a8e5/1282c19:dd:d9:dd:c25:c25b:d00a:a8e5
2312c19:dd:d9:dd:c25:c25b:d00a:a8e6/1282c19:dd:d9:dd:c25:c25b:d00a:a8e6
2322c19:dd:d9:dd:c25:c25b:d00a:a8e7/1282c19:dd:d9:dd:c25:c25b:d00a:a8e7
2332c19:dd:d9:dd:c25:c25b:d00a:a8e8/1282c19:dd:d9:dd:c25:c25b:d00a:a8e8
2342c19:dd:d9:dd:c25:c25b:d00a:a8e9/1282c19:dd:d9:dd:c25:c25b:d00a:a8e9
2352c19:dd:d9:dd:c25:c25b:d00a:a8ea/1282c19:dd:d9:dd:c25:c25b:d00a:a8ea
2362c19:dd:d9:dd:c25:c25b:d00a:a8eb/1282c19:dd:d9:dd:c25:c25b:d00a:a8eb
2372c19:dd:d9:dd:c25:c25b:d00a:a8ec/1282c19:dd:d9:dd:c25:c25b:d00a:a8ec
2382c19:dd:d9:dd:c25:c25b:d00a:a8ed/1282c19:dd:d9:dd:c25:c25b:d00a:a8ed
2392c19:dd:d9:dd:c25:c25b:d00a:a8ee/1282c19:dd:d9:dd:c25:c25b:d00a:a8ee
2402c19:dd:d9:dd:c25:c25b:d00a:a8ef/1282c19:dd:d9:dd:c25:c25b:d00a:a8ef
2412c19:dd:d9:dd:c25:c25b:d00a:a8f0/1282c19:dd:d9:dd:c25:c25b:d00a:a8f0
2422c19:dd:d9:dd:c25:c25b:d00a:a8f1/1282c19:dd:d9:dd:c25:c25b:d00a:a8f1
2432c19:dd:d9:dd:c25:c25b:d00a:a8f2/1282c19:dd:d9:dd:c25:c25b:d00a:a8f2
2442c19:dd:d9:dd:c25:c25b:d00a:a8f3/1282c19:dd:d9:dd:c25:c25b:d00a:a8f3
2452c19:dd:d9:dd:c25:c25b:d00a:a8f4/1282c19:dd:d9:dd:c25:c25b:d00a:a8f4
2462c19:dd:d9:dd:c25:c25b:d00a:a8f5/1282c19:dd:d9:dd:c25:c25b:d00a:a8f5
2472c19:dd:d9:dd:c25:c25b:d00a:a8f6/1282c19:dd:d9:dd:c25:c25b:d00a:a8f6
2482c19:dd:d9:dd:c25:c25b:d00a:a8f7/1282c19:dd:d9:dd:c25:c25b:d00a:a8f7
2492c19:dd:d9:dd:c25:c25b:d00a:a8f8/1282c19:dd:d9:dd:c25:c25b:d00a:a8f8
2502c19:dd:d9:dd:c25:c25b:d00a:a8f9/1282c19:dd:d9:dd:c25:c25b:d00a:a8f9
2512c19:dd:d9:dd:c25:c25b:d00a:a8fa/1282c19:dd:d9:dd:c25:c25b:d00a:a8fa
2522c19:dd:d9:dd:c25:c25b:d00a:a8fb/1282c19:dd:d9:dd:c25:c25b:d00a:a8fb
2532c19:dd:d9:dd:c25:c25b:d00a:a8fc/1282c19:dd:d9:dd:c25:c25b:d00a:a8fc
2542c19:dd:d9:dd:c25:c25b:d00a:a8fd/1282c19:dd:d9:dd:c25:c25b:d00a:a8fd
2552c19:dd:d9:dd:c25:c25b:d00a:a8fe/1282c19:dd:d9:dd:c25:c25b:d00a:a8fe
2562c19:dd:d9:dd:c25:c25b:d00a:a8ff/1282c19:dd:d9:dd:c25:c25b:d00a:a8ff

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.