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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:94de:a800/119
First address
2c19:dd:d9:dd:c25:c25:94de:a800
Last address
2c19:dd:d9:dd:c25:c25:94de:a9ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:a800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
8.a.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
9.a.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/127
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:d9:dd:c25:c25:94de:a800/119 makes 256 subnets of /127.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:a800/1272c19:dd:d9:dd:c25:c25:94de:a801
22c19:dd:d9:dd:c25:c25:94de:a802/1272c19:dd:d9:dd:c25:c25:94de:a803
32c19:dd:d9:dd:c25:c25:94de:a804/1272c19:dd:d9:dd:c25:c25:94de:a805
42c19:dd:d9:dd:c25:c25:94de:a806/1272c19:dd:d9:dd:c25:c25:94de:a807
52c19:dd:d9:dd:c25:c25:94de:a808/1272c19:dd:d9:dd:c25:c25:94de:a809
62c19:dd:d9:dd:c25:c25:94de:a80a/1272c19:dd:d9:dd:c25:c25:94de:a80b
72c19:dd:d9:dd:c25:c25:94de:a80c/1272c19:dd:d9:dd:c25:c25:94de:a80d
82c19:dd:d9:dd:c25:c25:94de:a80e/1272c19:dd:d9:dd:c25:c25:94de:a80f
92c19:dd:d9:dd:c25:c25:94de:a810/1272c19:dd:d9:dd:c25:c25:94de:a811
102c19:dd:d9:dd:c25:c25:94de:a812/1272c19:dd:d9:dd:c25:c25:94de:a813
112c19:dd:d9:dd:c25:c25:94de:a814/1272c19:dd:d9:dd:c25:c25:94de:a815
122c19:dd:d9:dd:c25:c25:94de:a816/1272c19:dd:d9:dd:c25:c25:94de:a817
132c19:dd:d9:dd:c25:c25:94de:a818/1272c19:dd:d9:dd:c25:c25:94de:a819
142c19:dd:d9:dd:c25:c25:94de:a81a/1272c19:dd:d9:dd:c25:c25:94de:a81b
152c19:dd:d9:dd:c25:c25:94de:a81c/1272c19:dd:d9:dd:c25:c25:94de:a81d
162c19:dd:d9:dd:c25:c25:94de:a81e/1272c19:dd:d9:dd:c25:c25:94de:a81f
172c19:dd:d9:dd:c25:c25:94de:a820/1272c19:dd:d9:dd:c25:c25:94de:a821
182c19:dd:d9:dd:c25:c25:94de:a822/1272c19:dd:d9:dd:c25:c25:94de:a823
192c19:dd:d9:dd:c25:c25:94de:a824/1272c19:dd:d9:dd:c25:c25:94de:a825
202c19:dd:d9:dd:c25:c25:94de:a826/1272c19:dd:d9:dd:c25:c25:94de:a827
212c19:dd:d9:dd:c25:c25:94de:a828/1272c19:dd:d9:dd:c25:c25:94de:a829
222c19:dd:d9:dd:c25:c25:94de:a82a/1272c19:dd:d9:dd:c25:c25:94de:a82b
232c19:dd:d9:dd:c25:c25:94de:a82c/1272c19:dd:d9:dd:c25:c25:94de:a82d
242c19:dd:d9:dd:c25:c25:94de:a82e/1272c19:dd:d9:dd:c25:c25:94de:a82f
252c19:dd:d9:dd:c25:c25:94de:a830/1272c19:dd:d9:dd:c25:c25:94de:a831
262c19:dd:d9:dd:c25:c25:94de:a832/1272c19:dd:d9:dd:c25:c25:94de:a833
272c19:dd:d9:dd:c25:c25:94de:a834/1272c19:dd:d9:dd:c25:c25:94de:a835
282c19:dd:d9:dd:c25:c25:94de:a836/1272c19:dd:d9:dd:c25:c25:94de:a837
292c19:dd:d9:dd:c25:c25:94de:a838/1272c19:dd:d9:dd:c25:c25:94de:a839
302c19:dd:d9:dd:c25:c25:94de:a83a/1272c19:dd:d9:dd:c25:c25:94de:a83b
312c19:dd:d9:dd:c25:c25:94de:a83c/1272c19:dd:d9:dd:c25:c25:94de:a83d
322c19:dd:d9:dd:c25:c25:94de:a83e/1272c19:dd:d9:dd:c25:c25:94de:a83f
332c19:dd:d9:dd:c25:c25:94de:a840/1272c19:dd:d9:dd:c25:c25:94de:a841
342c19:dd:d9:dd:c25:c25:94de:a842/1272c19:dd:d9:dd:c25:c25:94de:a843
352c19:dd:d9:dd:c25:c25:94de:a844/1272c19:dd:d9:dd:c25:c25:94de:a845
362c19:dd:d9:dd:c25:c25:94de:a846/1272c19:dd:d9:dd:c25:c25:94de:a847
372c19:dd:d9:dd:c25:c25:94de:a848/1272c19:dd:d9:dd:c25:c25:94de:a849
382c19:dd:d9:dd:c25:c25:94de:a84a/1272c19:dd:d9:dd:c25:c25:94de:a84b
392c19:dd:d9:dd:c25:c25:94de:a84c/1272c19:dd:d9:dd:c25:c25:94de:a84d
402c19:dd:d9:dd:c25:c25:94de:a84e/1272c19:dd:d9:dd:c25:c25:94de:a84f
412c19:dd:d9:dd:c25:c25:94de:a850/1272c19:dd:d9:dd:c25:c25:94de:a851
422c19:dd:d9:dd:c25:c25:94de:a852/1272c19:dd:d9:dd:c25:c25:94de:a853
432c19:dd:d9:dd:c25:c25:94de:a854/1272c19:dd:d9:dd:c25:c25:94de:a855
442c19:dd:d9:dd:c25:c25:94de:a856/1272c19:dd:d9:dd:c25:c25:94de:a857
452c19:dd:d9:dd:c25:c25:94de:a858/1272c19:dd:d9:dd:c25:c25:94de:a859
462c19:dd:d9:dd:c25:c25:94de:a85a/1272c19:dd:d9:dd:c25:c25:94de:a85b
472c19:dd:d9:dd:c25:c25:94de:a85c/1272c19:dd:d9:dd:c25:c25:94de:a85d
482c19:dd:d9:dd:c25:c25:94de:a85e/1272c19:dd:d9:dd:c25:c25:94de:a85f
492c19:dd:d9:dd:c25:c25:94de:a860/1272c19:dd:d9:dd:c25:c25:94de:a861
502c19:dd:d9:dd:c25:c25:94de:a862/1272c19:dd:d9:dd:c25:c25:94de:a863
512c19:dd:d9:dd:c25:c25:94de:a864/1272c19:dd:d9:dd:c25:c25:94de:a865
522c19:dd:d9:dd:c25:c25:94de:a866/1272c19:dd:d9:dd:c25:c25:94de:a867
532c19:dd:d9:dd:c25:c25:94de:a868/1272c19:dd:d9:dd:c25:c25:94de:a869
542c19:dd:d9:dd:c25:c25:94de:a86a/1272c19:dd:d9:dd:c25:c25:94de:a86b
552c19:dd:d9:dd:c25:c25:94de:a86c/1272c19:dd:d9:dd:c25:c25:94de:a86d
562c19:dd:d9:dd:c25:c25:94de:a86e/1272c19:dd:d9:dd:c25:c25:94de:a86f
572c19:dd:d9:dd:c25:c25:94de:a870/1272c19:dd:d9:dd:c25:c25:94de:a871
582c19:dd:d9:dd:c25:c25:94de:a872/1272c19:dd:d9:dd:c25:c25:94de:a873
592c19:dd:d9:dd:c25:c25:94de:a874/1272c19:dd:d9:dd:c25:c25:94de:a875
602c19:dd:d9:dd:c25:c25:94de:a876/1272c19:dd:d9:dd:c25:c25:94de:a877
612c19:dd:d9:dd:c25:c25:94de:a878/1272c19:dd:d9:dd:c25:c25:94de:a879
622c19:dd:d9:dd:c25:c25:94de:a87a/1272c19:dd:d9:dd:c25:c25:94de:a87b
632c19:dd:d9:dd:c25:c25:94de:a87c/1272c19:dd:d9:dd:c25:c25:94de:a87d
642c19:dd:d9:dd:c25:c25:94de:a87e/1272c19:dd:d9:dd:c25:c25:94de:a87f
652c19:dd:d9:dd:c25:c25:94de:a880/1272c19:dd:d9:dd:c25:c25:94de:a881
662c19:dd:d9:dd:c25:c25:94de:a882/1272c19:dd:d9:dd:c25:c25:94de:a883
672c19:dd:d9:dd:c25:c25:94de:a884/1272c19:dd:d9:dd:c25:c25:94de:a885
682c19:dd:d9:dd:c25:c25:94de:a886/1272c19:dd:d9:dd:c25:c25:94de:a887
692c19:dd:d9:dd:c25:c25:94de:a888/1272c19:dd:d9:dd:c25:c25:94de:a889
702c19:dd:d9:dd:c25:c25:94de:a88a/1272c19:dd:d9:dd:c25:c25:94de:a88b
712c19:dd:d9:dd:c25:c25:94de:a88c/1272c19:dd:d9:dd:c25:c25:94de:a88d
722c19:dd:d9:dd:c25:c25:94de:a88e/1272c19:dd:d9:dd:c25:c25:94de:a88f
732c19:dd:d9:dd:c25:c25:94de:a890/1272c19:dd:d9:dd:c25:c25:94de:a891
742c19:dd:d9:dd:c25:c25:94de:a892/1272c19:dd:d9:dd:c25:c25:94de:a893
752c19:dd:d9:dd:c25:c25:94de:a894/1272c19:dd:d9:dd:c25:c25:94de:a895
762c19:dd:d9:dd:c25:c25:94de:a896/1272c19:dd:d9:dd:c25:c25:94de:a897
772c19:dd:d9:dd:c25:c25:94de:a898/1272c19:dd:d9:dd:c25:c25:94de:a899
782c19:dd:d9:dd:c25:c25:94de:a89a/1272c19:dd:d9:dd:c25:c25:94de:a89b
792c19:dd:d9:dd:c25:c25:94de:a89c/1272c19:dd:d9:dd:c25:c25:94de:a89d
802c19:dd:d9:dd:c25:c25:94de:a89e/1272c19:dd:d9:dd:c25:c25:94de:a89f
812c19:dd:d9:dd:c25:c25:94de:a8a0/1272c19:dd:d9:dd:c25:c25:94de:a8a1
822c19:dd:d9:dd:c25:c25:94de:a8a2/1272c19:dd:d9:dd:c25:c25:94de:a8a3
832c19:dd:d9:dd:c25:c25:94de:a8a4/1272c19:dd:d9:dd:c25:c25:94de:a8a5
842c19:dd:d9:dd:c25:c25:94de:a8a6/1272c19:dd:d9:dd:c25:c25:94de:a8a7
852c19:dd:d9:dd:c25:c25:94de:a8a8/1272c19:dd:d9:dd:c25:c25:94de:a8a9
862c19:dd:d9:dd:c25:c25:94de:a8aa/1272c19:dd:d9:dd:c25:c25:94de:a8ab
872c19:dd:d9:dd:c25:c25:94de:a8ac/1272c19:dd:d9:dd:c25:c25:94de:a8ad
882c19:dd:d9:dd:c25:c25:94de:a8ae/1272c19:dd:d9:dd:c25:c25:94de:a8af
892c19:dd:d9:dd:c25:c25:94de:a8b0/1272c19:dd:d9:dd:c25:c25:94de:a8b1
902c19:dd:d9:dd:c25:c25:94de:a8b2/1272c19:dd:d9:dd:c25:c25:94de:a8b3
912c19:dd:d9:dd:c25:c25:94de:a8b4/1272c19:dd:d9:dd:c25:c25:94de:a8b5
922c19:dd:d9:dd:c25:c25:94de:a8b6/1272c19:dd:d9:dd:c25:c25:94de:a8b7
932c19:dd:d9:dd:c25:c25:94de:a8b8/1272c19:dd:d9:dd:c25:c25:94de:a8b9
942c19:dd:d9:dd:c25:c25:94de:a8ba/1272c19:dd:d9:dd:c25:c25:94de:a8bb
952c19:dd:d9:dd:c25:c25:94de:a8bc/1272c19:dd:d9:dd:c25:c25:94de:a8bd
962c19:dd:d9:dd:c25:c25:94de:a8be/1272c19:dd:d9:dd:c25:c25:94de:a8bf
972c19:dd:d9:dd:c25:c25:94de:a8c0/1272c19:dd:d9:dd:c25:c25:94de:a8c1
982c19:dd:d9:dd:c25:c25:94de:a8c2/1272c19:dd:d9:dd:c25:c25:94de:a8c3
992c19:dd:d9:dd:c25:c25:94de:a8c4/1272c19:dd:d9:dd:c25:c25:94de:a8c5
1002c19:dd:d9:dd:c25:c25:94de:a8c6/1272c19:dd:d9:dd:c25:c25:94de:a8c7
1012c19:dd:d9:dd:c25:c25:94de:a8c8/1272c19:dd:d9:dd:c25:c25:94de:a8c9
1022c19:dd:d9:dd:c25:c25:94de:a8ca/1272c19:dd:d9:dd:c25:c25:94de:a8cb
1032c19:dd:d9:dd:c25:c25:94de:a8cc/1272c19:dd:d9:dd:c25:c25:94de:a8cd
1042c19:dd:d9:dd:c25:c25:94de:a8ce/1272c19:dd:d9:dd:c25:c25:94de:a8cf
1052c19:dd:d9:dd:c25:c25:94de:a8d0/1272c19:dd:d9:dd:c25:c25:94de:a8d1
1062c19:dd:d9:dd:c25:c25:94de:a8d2/1272c19:dd:d9:dd:c25:c25:94de:a8d3
1072c19:dd:d9:dd:c25:c25:94de:a8d4/1272c19:dd:d9:dd:c25:c25:94de:a8d5
1082c19:dd:d9:dd:c25:c25:94de:a8d6/1272c19:dd:d9:dd:c25:c25:94de:a8d7
1092c19:dd:d9:dd:c25:c25:94de:a8d8/1272c19:dd:d9:dd:c25:c25:94de:a8d9
1102c19:dd:d9:dd:c25:c25:94de:a8da/1272c19:dd:d9:dd:c25:c25:94de:a8db
1112c19:dd:d9:dd:c25:c25:94de:a8dc/1272c19:dd:d9:dd:c25:c25:94de:a8dd
1122c19:dd:d9:dd:c25:c25:94de:a8de/1272c19:dd:d9:dd:c25:c25:94de:a8df
1132c19:dd:d9:dd:c25:c25:94de:a8e0/1272c19:dd:d9:dd:c25:c25:94de:a8e1
1142c19:dd:d9:dd:c25:c25:94de:a8e2/1272c19:dd:d9:dd:c25:c25:94de:a8e3
1152c19:dd:d9:dd:c25:c25:94de:a8e4/1272c19:dd:d9:dd:c25:c25:94de:a8e5
1162c19:dd:d9:dd:c25:c25:94de:a8e6/1272c19:dd:d9:dd:c25:c25:94de:a8e7
1172c19:dd:d9:dd:c25:c25:94de:a8e8/1272c19:dd:d9:dd:c25:c25:94de:a8e9
1182c19:dd:d9:dd:c25:c25:94de:a8ea/1272c19:dd:d9:dd:c25:c25:94de:a8eb
1192c19:dd:d9:dd:c25:c25:94de:a8ec/1272c19:dd:d9:dd:c25:c25:94de:a8ed
1202c19:dd:d9:dd:c25:c25:94de:a8ee/1272c19:dd:d9:dd:c25:c25:94de:a8ef
1212c19:dd:d9:dd:c25:c25:94de:a8f0/1272c19:dd:d9:dd:c25:c25:94de:a8f1
1222c19:dd:d9:dd:c25:c25:94de:a8f2/1272c19:dd:d9:dd:c25:c25:94de:a8f3
1232c19:dd:d9:dd:c25:c25:94de:a8f4/1272c19:dd:d9:dd:c25:c25:94de:a8f5
1242c19:dd:d9:dd:c25:c25:94de:a8f6/1272c19:dd:d9:dd:c25:c25:94de:a8f7
1252c19:dd:d9:dd:c25:c25:94de:a8f8/1272c19:dd:d9:dd:c25:c25:94de:a8f9
1262c19:dd:d9:dd:c25:c25:94de:a8fa/1272c19:dd:d9:dd:c25:c25:94de:a8fb
1272c19:dd:d9:dd:c25:c25:94de:a8fc/1272c19:dd:d9:dd:c25:c25:94de:a8fd
1282c19:dd:d9:dd:c25:c25:94de:a8fe/1272c19:dd:d9:dd:c25:c25:94de:a8ff
1292c19:dd:d9:dd:c25:c25:94de:a900/1272c19:dd:d9:dd:c25:c25:94de:a901
1302c19:dd:d9:dd:c25:c25:94de:a902/1272c19:dd:d9:dd:c25:c25:94de:a903
1312c19:dd:d9:dd:c25:c25:94de:a904/1272c19:dd:d9:dd:c25:c25:94de:a905
1322c19:dd:d9:dd:c25:c25:94de:a906/1272c19:dd:d9:dd:c25:c25:94de:a907
1332c19:dd:d9:dd:c25:c25:94de:a908/1272c19:dd:d9:dd:c25:c25:94de:a909
1342c19:dd:d9:dd:c25:c25:94de:a90a/1272c19:dd:d9:dd:c25:c25:94de:a90b
1352c19:dd:d9:dd:c25:c25:94de:a90c/1272c19:dd:d9:dd:c25:c25:94de:a90d
1362c19:dd:d9:dd:c25:c25:94de:a90e/1272c19:dd:d9:dd:c25:c25:94de:a90f
1372c19:dd:d9:dd:c25:c25:94de:a910/1272c19:dd:d9:dd:c25:c25:94de:a911
1382c19:dd:d9:dd:c25:c25:94de:a912/1272c19:dd:d9:dd:c25:c25:94de:a913
1392c19:dd:d9:dd:c25:c25:94de:a914/1272c19:dd:d9:dd:c25:c25:94de:a915
1402c19:dd:d9:dd:c25:c25:94de:a916/1272c19:dd:d9:dd:c25:c25:94de:a917
1412c19:dd:d9:dd:c25:c25:94de:a918/1272c19:dd:d9:dd:c25:c25:94de:a919
1422c19:dd:d9:dd:c25:c25:94de:a91a/1272c19:dd:d9:dd:c25:c25:94de:a91b
1432c19:dd:d9:dd:c25:c25:94de:a91c/1272c19:dd:d9:dd:c25:c25:94de:a91d
1442c19:dd:d9:dd:c25:c25:94de:a91e/1272c19:dd:d9:dd:c25:c25:94de:a91f
1452c19:dd:d9:dd:c25:c25:94de:a920/1272c19:dd:d9:dd:c25:c25:94de:a921
1462c19:dd:d9:dd:c25:c25:94de:a922/1272c19:dd:d9:dd:c25:c25:94de:a923
1472c19:dd:d9:dd:c25:c25:94de:a924/1272c19:dd:d9:dd:c25:c25:94de:a925
1482c19:dd:d9:dd:c25:c25:94de:a926/1272c19:dd:d9:dd:c25:c25:94de:a927
1492c19:dd:d9:dd:c25:c25:94de:a928/1272c19:dd:d9:dd:c25:c25:94de:a929
1502c19:dd:d9:dd:c25:c25:94de:a92a/1272c19:dd:d9:dd:c25:c25:94de:a92b
1512c19:dd:d9:dd:c25:c25:94de:a92c/1272c19:dd:d9:dd:c25:c25:94de:a92d
1522c19:dd:d9:dd:c25:c25:94de:a92e/1272c19:dd:d9:dd:c25:c25:94de:a92f
1532c19:dd:d9:dd:c25:c25:94de:a930/1272c19:dd:d9:dd:c25:c25:94de:a931
1542c19:dd:d9:dd:c25:c25:94de:a932/1272c19:dd:d9:dd:c25:c25:94de:a933
1552c19:dd:d9:dd:c25:c25:94de:a934/1272c19:dd:d9:dd:c25:c25:94de:a935
1562c19:dd:d9:dd:c25:c25:94de:a936/1272c19:dd:d9:dd:c25:c25:94de:a937
1572c19:dd:d9:dd:c25:c25:94de:a938/1272c19:dd:d9:dd:c25:c25:94de:a939
1582c19:dd:d9:dd:c25:c25:94de:a93a/1272c19:dd:d9:dd:c25:c25:94de:a93b
1592c19:dd:d9:dd:c25:c25:94de:a93c/1272c19:dd:d9:dd:c25:c25:94de:a93d
1602c19:dd:d9:dd:c25:c25:94de:a93e/1272c19:dd:d9:dd:c25:c25:94de:a93f
1612c19:dd:d9:dd:c25:c25:94de:a940/1272c19:dd:d9:dd:c25:c25:94de:a941
1622c19:dd:d9:dd:c25:c25:94de:a942/1272c19:dd:d9:dd:c25:c25:94de:a943
1632c19:dd:d9:dd:c25:c25:94de:a944/1272c19:dd:d9:dd:c25:c25:94de:a945
1642c19:dd:d9:dd:c25:c25:94de:a946/1272c19:dd:d9:dd:c25:c25:94de:a947
1652c19:dd:d9:dd:c25:c25:94de:a948/1272c19:dd:d9:dd:c25:c25:94de:a949
1662c19:dd:d9:dd:c25:c25:94de:a94a/1272c19:dd:d9:dd:c25:c25:94de:a94b
1672c19:dd:d9:dd:c25:c25:94de:a94c/1272c19:dd:d9:dd:c25:c25:94de:a94d
1682c19:dd:d9:dd:c25:c25:94de:a94e/1272c19:dd:d9:dd:c25:c25:94de:a94f
1692c19:dd:d9:dd:c25:c25:94de:a950/1272c19:dd:d9:dd:c25:c25:94de:a951
1702c19:dd:d9:dd:c25:c25:94de:a952/1272c19:dd:d9:dd:c25:c25:94de:a953
1712c19:dd:d9:dd:c25:c25:94de:a954/1272c19:dd:d9:dd:c25:c25:94de:a955
1722c19:dd:d9:dd:c25:c25:94de:a956/1272c19:dd:d9:dd:c25:c25:94de:a957
1732c19:dd:d9:dd:c25:c25:94de:a958/1272c19:dd:d9:dd:c25:c25:94de:a959
1742c19:dd:d9:dd:c25:c25:94de:a95a/1272c19:dd:d9:dd:c25:c25:94de:a95b
1752c19:dd:d9:dd:c25:c25:94de:a95c/1272c19:dd:d9:dd:c25:c25:94de:a95d
1762c19:dd:d9:dd:c25:c25:94de:a95e/1272c19:dd:d9:dd:c25:c25:94de:a95f
1772c19:dd:d9:dd:c25:c25:94de:a960/1272c19:dd:d9:dd:c25:c25:94de:a961
1782c19:dd:d9:dd:c25:c25:94de:a962/1272c19:dd:d9:dd:c25:c25:94de:a963
1792c19:dd:d9:dd:c25:c25:94de:a964/1272c19:dd:d9:dd:c25:c25:94de:a965
1802c19:dd:d9:dd:c25:c25:94de:a966/1272c19:dd:d9:dd:c25:c25:94de:a967
1812c19:dd:d9:dd:c25:c25:94de:a968/1272c19:dd:d9:dd:c25:c25:94de:a969
1822c19:dd:d9:dd:c25:c25:94de:a96a/1272c19:dd:d9:dd:c25:c25:94de:a96b
1832c19:dd:d9:dd:c25:c25:94de:a96c/1272c19:dd:d9:dd:c25:c25:94de:a96d
1842c19:dd:d9:dd:c25:c25:94de:a96e/1272c19:dd:d9:dd:c25:c25:94de:a96f
1852c19:dd:d9:dd:c25:c25:94de:a970/1272c19:dd:d9:dd:c25:c25:94de:a971
1862c19:dd:d9:dd:c25:c25:94de:a972/1272c19:dd:d9:dd:c25:c25:94de:a973
1872c19:dd:d9:dd:c25:c25:94de:a974/1272c19:dd:d9:dd:c25:c25:94de:a975
1882c19:dd:d9:dd:c25:c25:94de:a976/1272c19:dd:d9:dd:c25:c25:94de:a977
1892c19:dd:d9:dd:c25:c25:94de:a978/1272c19:dd:d9:dd:c25:c25:94de:a979
1902c19:dd:d9:dd:c25:c25:94de:a97a/1272c19:dd:d9:dd:c25:c25:94de:a97b
1912c19:dd:d9:dd:c25:c25:94de:a97c/1272c19:dd:d9:dd:c25:c25:94de:a97d
1922c19:dd:d9:dd:c25:c25:94de:a97e/1272c19:dd:d9:dd:c25:c25:94de:a97f
1932c19:dd:d9:dd:c25:c25:94de:a980/1272c19:dd:d9:dd:c25:c25:94de:a981
1942c19:dd:d9:dd:c25:c25:94de:a982/1272c19:dd:d9:dd:c25:c25:94de:a983
1952c19:dd:d9:dd:c25:c25:94de:a984/1272c19:dd:d9:dd:c25:c25:94de:a985
1962c19:dd:d9:dd:c25:c25:94de:a986/1272c19:dd:d9:dd:c25:c25:94de:a987
1972c19:dd:d9:dd:c25:c25:94de:a988/1272c19:dd:d9:dd:c25:c25:94de:a989
1982c19:dd:d9:dd:c25:c25:94de:a98a/1272c19:dd:d9:dd:c25:c25:94de:a98b
1992c19:dd:d9:dd:c25:c25:94de:a98c/1272c19:dd:d9:dd:c25:c25:94de:a98d
2002c19:dd:d9:dd:c25:c25:94de:a98e/1272c19:dd:d9:dd:c25:c25:94de:a98f
2012c19:dd:d9:dd:c25:c25:94de:a990/1272c19:dd:d9:dd:c25:c25:94de:a991
2022c19:dd:d9:dd:c25:c25:94de:a992/1272c19:dd:d9:dd:c25:c25:94de:a993
2032c19:dd:d9:dd:c25:c25:94de:a994/1272c19:dd:d9:dd:c25:c25:94de:a995
2042c19:dd:d9:dd:c25:c25:94de:a996/1272c19:dd:d9:dd:c25:c25:94de:a997
2052c19:dd:d9:dd:c25:c25:94de:a998/1272c19:dd:d9:dd:c25:c25:94de:a999
2062c19:dd:d9:dd:c25:c25:94de:a99a/1272c19:dd:d9:dd:c25:c25:94de:a99b
2072c19:dd:d9:dd:c25:c25:94de:a99c/1272c19:dd:d9:dd:c25:c25:94de:a99d
2082c19:dd:d9:dd:c25:c25:94de:a99e/1272c19:dd:d9:dd:c25:c25:94de:a99f
2092c19:dd:d9:dd:c25:c25:94de:a9a0/1272c19:dd:d9:dd:c25:c25:94de:a9a1
2102c19:dd:d9:dd:c25:c25:94de:a9a2/1272c19:dd:d9:dd:c25:c25:94de:a9a3
2112c19:dd:d9:dd:c25:c25:94de:a9a4/1272c19:dd:d9:dd:c25:c25:94de:a9a5
2122c19:dd:d9:dd:c25:c25:94de:a9a6/1272c19:dd:d9:dd:c25:c25:94de:a9a7
2132c19:dd:d9:dd:c25:c25:94de:a9a8/1272c19:dd:d9:dd:c25:c25:94de:a9a9
2142c19:dd:d9:dd:c25:c25:94de:a9aa/1272c19:dd:d9:dd:c25:c25:94de:a9ab
2152c19:dd:d9:dd:c25:c25:94de:a9ac/1272c19:dd:d9:dd:c25:c25:94de:a9ad
2162c19:dd:d9:dd:c25:c25:94de:a9ae/1272c19:dd:d9:dd:c25:c25:94de:a9af
2172c19:dd:d9:dd:c25:c25:94de:a9b0/1272c19:dd:d9:dd:c25:c25:94de:a9b1
2182c19:dd:d9:dd:c25:c25:94de:a9b2/1272c19:dd:d9:dd:c25:c25:94de:a9b3
2192c19:dd:d9:dd:c25:c25:94de:a9b4/1272c19:dd:d9:dd:c25:c25:94de:a9b5
2202c19:dd:d9:dd:c25:c25:94de:a9b6/1272c19:dd:d9:dd:c25:c25:94de:a9b7
2212c19:dd:d9:dd:c25:c25:94de:a9b8/1272c19:dd:d9:dd:c25:c25:94de:a9b9
2222c19:dd:d9:dd:c25:c25:94de:a9ba/1272c19:dd:d9:dd:c25:c25:94de:a9bb
2232c19:dd:d9:dd:c25:c25:94de:a9bc/1272c19:dd:d9:dd:c25:c25:94de:a9bd
2242c19:dd:d9:dd:c25:c25:94de:a9be/1272c19:dd:d9:dd:c25:c25:94de:a9bf
2252c19:dd:d9:dd:c25:c25:94de:a9c0/1272c19:dd:d9:dd:c25:c25:94de:a9c1
2262c19:dd:d9:dd:c25:c25:94de:a9c2/1272c19:dd:d9:dd:c25:c25:94de:a9c3
2272c19:dd:d9:dd:c25:c25:94de:a9c4/1272c19:dd:d9:dd:c25:c25:94de:a9c5
2282c19:dd:d9:dd:c25:c25:94de:a9c6/1272c19:dd:d9:dd:c25:c25:94de:a9c7
2292c19:dd:d9:dd:c25:c25:94de:a9c8/1272c19:dd:d9:dd:c25:c25:94de:a9c9
2302c19:dd:d9:dd:c25:c25:94de:a9ca/1272c19:dd:d9:dd:c25:c25:94de:a9cb
2312c19:dd:d9:dd:c25:c25:94de:a9cc/1272c19:dd:d9:dd:c25:c25:94de:a9cd
2322c19:dd:d9:dd:c25:c25:94de:a9ce/1272c19:dd:d9:dd:c25:c25:94de:a9cf
2332c19:dd:d9:dd:c25:c25:94de:a9d0/1272c19:dd:d9:dd:c25:c25:94de:a9d1
2342c19:dd:d9:dd:c25:c25:94de:a9d2/1272c19:dd:d9:dd:c25:c25:94de:a9d3
2352c19:dd:d9:dd:c25:c25:94de:a9d4/1272c19:dd:d9:dd:c25:c25:94de:a9d5
2362c19:dd:d9:dd:c25:c25:94de:a9d6/1272c19:dd:d9:dd:c25:c25:94de:a9d7
2372c19:dd:d9:dd:c25:c25:94de:a9d8/1272c19:dd:d9:dd:c25:c25:94de:a9d9
2382c19:dd:d9:dd:c25:c25:94de:a9da/1272c19:dd:d9:dd:c25:c25:94de:a9db
2392c19:dd:d9:dd:c25:c25:94de:a9dc/1272c19:dd:d9:dd:c25:c25:94de:a9dd
2402c19:dd:d9:dd:c25:c25:94de:a9de/1272c19:dd:d9:dd:c25:c25:94de:a9df
2412c19:dd:d9:dd:c25:c25:94de:a9e0/1272c19:dd:d9:dd:c25:c25:94de:a9e1
2422c19:dd:d9:dd:c25:c25:94de:a9e2/1272c19:dd:d9:dd:c25:c25:94de:a9e3
2432c19:dd:d9:dd:c25:c25:94de:a9e4/1272c19:dd:d9:dd:c25:c25:94de:a9e5
2442c19:dd:d9:dd:c25:c25:94de:a9e6/1272c19:dd:d9:dd:c25:c25:94de:a9e7
2452c19:dd:d9:dd:c25:c25:94de:a9e8/1272c19:dd:d9:dd:c25:c25:94de:a9e9
2462c19:dd:d9:dd:c25:c25:94de:a9ea/1272c19:dd:d9:dd:c25:c25:94de:a9eb
2472c19:dd:d9:dd:c25:c25:94de:a9ec/1272c19:dd:d9:dd:c25:c25:94de:a9ed
2482c19:dd:d9:dd:c25:c25:94de:a9ee/1272c19:dd:d9:dd:c25:c25:94de:a9ef
2492c19:dd:d9:dd:c25:c25:94de:a9f0/1272c19:dd:d9:dd:c25:c25:94de:a9f1
2502c19:dd:d9:dd:c25:c25:94de:a9f2/1272c19:dd:d9:dd:c25:c25:94de:a9f3
2512c19:dd:d9:dd:c25:c25:94de:a9f4/1272c19:dd:d9:dd:c25:c25:94de:a9f5
2522c19:dd:d9:dd:c25:c25:94de:a9f6/1272c19:dd:d9:dd:c25:c25:94de:a9f7
2532c19:dd:d9:dd:c25:c25:94de:a9f8/1272c19:dd:d9:dd:c25:c25:94de:a9f9
2542c19:dd:d9:dd:c25:c25:94de:a9fa/1272c19:dd:d9:dd:c25:c25:94de:a9fb
2552c19:dd:d9:dd:c25:c25:94de:a9fc/1272c19:dd:d9:dd:c25:c25:94de:a9fd
2562c19:dd:d9:dd:c25:c25:94de:a9fe/1272c19:dd:d9:dd:c25:c25:94de:a9ff

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.