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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:dd0:ec00:c25:c25:ec00:700/120
First address
2c19:dd:dd0:ec00:c25:c25:ec00:700
Last address
2c19:dd:dd0:ec00:c25:c25:ec00:7ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0dd0:ec00:0c25:0c25:ec00:0700
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
7.0.0.0.c.e.5.2.c.0.5.2.c.0.0.0.c.e.0.d.d.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:dd0:ec00:c25:c25:ec00:700/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:dd0:ec00:c25:c25:ec00:700/1282c19:dd:dd0:ec00:c25:c25:ec00:700
22c19:dd:dd0:ec00:c25:c25:ec00:701/1282c19:dd:dd0:ec00:c25:c25:ec00:701
32c19:dd:dd0:ec00:c25:c25:ec00:702/1282c19:dd:dd0:ec00:c25:c25:ec00:702
42c19:dd:dd0:ec00:c25:c25:ec00:703/1282c19:dd:dd0:ec00:c25:c25:ec00:703
52c19:dd:dd0:ec00:c25:c25:ec00:704/1282c19:dd:dd0:ec00:c25:c25:ec00:704
62c19:dd:dd0:ec00:c25:c25:ec00:705/1282c19:dd:dd0:ec00:c25:c25:ec00:705
72c19:dd:dd0:ec00:c25:c25:ec00:706/1282c19:dd:dd0:ec00:c25:c25:ec00:706
82c19:dd:dd0:ec00:c25:c25:ec00:707/1282c19:dd:dd0:ec00:c25:c25:ec00:707
92c19:dd:dd0:ec00:c25:c25:ec00:708/1282c19:dd:dd0:ec00:c25:c25:ec00:708
102c19:dd:dd0:ec00:c25:c25:ec00:709/1282c19:dd:dd0:ec00:c25:c25:ec00:709
112c19:dd:dd0:ec00:c25:c25:ec00:70a/1282c19:dd:dd0:ec00:c25:c25:ec00:70a
122c19:dd:dd0:ec00:c25:c25:ec00:70b/1282c19:dd:dd0:ec00:c25:c25:ec00:70b
132c19:dd:dd0:ec00:c25:c25:ec00:70c/1282c19:dd:dd0:ec00:c25:c25:ec00:70c
142c19:dd:dd0:ec00:c25:c25:ec00:70d/1282c19:dd:dd0:ec00:c25:c25:ec00:70d
152c19:dd:dd0:ec00:c25:c25:ec00:70e/1282c19:dd:dd0:ec00:c25:c25:ec00:70e
162c19:dd:dd0:ec00:c25:c25:ec00:70f/1282c19:dd:dd0:ec00:c25:c25:ec00:70f
172c19:dd:dd0:ec00:c25:c25:ec00:710/1282c19:dd:dd0:ec00:c25:c25:ec00:710
182c19:dd:dd0:ec00:c25:c25:ec00:711/1282c19:dd:dd0:ec00:c25:c25:ec00:711
192c19:dd:dd0:ec00:c25:c25:ec00:712/1282c19:dd:dd0:ec00:c25:c25:ec00:712
202c19:dd:dd0:ec00:c25:c25:ec00:713/1282c19:dd:dd0:ec00:c25:c25:ec00:713
212c19:dd:dd0:ec00:c25:c25:ec00:714/1282c19:dd:dd0:ec00:c25:c25:ec00:714
222c19:dd:dd0:ec00:c25:c25:ec00:715/1282c19:dd:dd0:ec00:c25:c25:ec00:715
232c19:dd:dd0:ec00:c25:c25:ec00:716/1282c19:dd:dd0:ec00:c25:c25:ec00:716
242c19:dd:dd0:ec00:c25:c25:ec00:717/1282c19:dd:dd0:ec00:c25:c25:ec00:717
252c19:dd:dd0:ec00:c25:c25:ec00:718/1282c19:dd:dd0:ec00:c25:c25:ec00:718
262c19:dd:dd0:ec00:c25:c25:ec00:719/1282c19:dd:dd0:ec00:c25:c25:ec00:719
272c19:dd:dd0:ec00:c25:c25:ec00:71a/1282c19:dd:dd0:ec00:c25:c25:ec00:71a
282c19:dd:dd0:ec00:c25:c25:ec00:71b/1282c19:dd:dd0:ec00:c25:c25:ec00:71b
292c19:dd:dd0:ec00:c25:c25:ec00:71c/1282c19:dd:dd0:ec00:c25:c25:ec00:71c
302c19:dd:dd0:ec00:c25:c25:ec00:71d/1282c19:dd:dd0:ec00:c25:c25:ec00:71d
312c19:dd:dd0:ec00:c25:c25:ec00:71e/1282c19:dd:dd0:ec00:c25:c25:ec00:71e
322c19:dd:dd0:ec00:c25:c25:ec00:71f/1282c19:dd:dd0:ec00:c25:c25:ec00:71f
332c19:dd:dd0:ec00:c25:c25:ec00:720/1282c19:dd:dd0:ec00:c25:c25:ec00:720
342c19:dd:dd0:ec00:c25:c25:ec00:721/1282c19:dd:dd0:ec00:c25:c25:ec00:721
352c19:dd:dd0:ec00:c25:c25:ec00:722/1282c19:dd:dd0:ec00:c25:c25:ec00:722
362c19:dd:dd0:ec00:c25:c25:ec00:723/1282c19:dd:dd0:ec00:c25:c25:ec00:723
372c19:dd:dd0:ec00:c25:c25:ec00:724/1282c19:dd:dd0:ec00:c25:c25:ec00:724
382c19:dd:dd0:ec00:c25:c25:ec00:725/1282c19:dd:dd0:ec00:c25:c25:ec00:725
392c19:dd:dd0:ec00:c25:c25:ec00:726/1282c19:dd:dd0:ec00:c25:c25:ec00:726
402c19:dd:dd0:ec00:c25:c25:ec00:727/1282c19:dd:dd0:ec00:c25:c25:ec00:727
412c19:dd:dd0:ec00:c25:c25:ec00:728/1282c19:dd:dd0:ec00:c25:c25:ec00:728
422c19:dd:dd0:ec00:c25:c25:ec00:729/1282c19:dd:dd0:ec00:c25:c25:ec00:729
432c19:dd:dd0:ec00:c25:c25:ec00:72a/1282c19:dd:dd0:ec00:c25:c25:ec00:72a
442c19:dd:dd0:ec00:c25:c25:ec00:72b/1282c19:dd:dd0:ec00:c25:c25:ec00:72b
452c19:dd:dd0:ec00:c25:c25:ec00:72c/1282c19:dd:dd0:ec00:c25:c25:ec00:72c
462c19:dd:dd0:ec00:c25:c25:ec00:72d/1282c19:dd:dd0:ec00:c25:c25:ec00:72d
472c19:dd:dd0:ec00:c25:c25:ec00:72e/1282c19:dd:dd0:ec00:c25:c25:ec00:72e
482c19:dd:dd0:ec00:c25:c25:ec00:72f/1282c19:dd:dd0:ec00:c25:c25:ec00:72f
492c19:dd:dd0:ec00:c25:c25:ec00:730/1282c19:dd:dd0:ec00:c25:c25:ec00:730
502c19:dd:dd0:ec00:c25:c25:ec00:731/1282c19:dd:dd0:ec00:c25:c25:ec00:731
512c19:dd:dd0:ec00:c25:c25:ec00:732/1282c19:dd:dd0:ec00:c25:c25:ec00:732
522c19:dd:dd0:ec00:c25:c25:ec00:733/1282c19:dd:dd0:ec00:c25:c25:ec00:733
532c19:dd:dd0:ec00:c25:c25:ec00:734/1282c19:dd:dd0:ec00:c25:c25:ec00:734
542c19:dd:dd0:ec00:c25:c25:ec00:735/1282c19:dd:dd0:ec00:c25:c25:ec00:735
552c19:dd:dd0:ec00:c25:c25:ec00:736/1282c19:dd:dd0:ec00:c25:c25:ec00:736
562c19:dd:dd0:ec00:c25:c25:ec00:737/1282c19:dd:dd0:ec00:c25:c25:ec00:737
572c19:dd:dd0:ec00:c25:c25:ec00:738/1282c19:dd:dd0:ec00:c25:c25:ec00:738
582c19:dd:dd0:ec00:c25:c25:ec00:739/1282c19:dd:dd0:ec00:c25:c25:ec00:739
592c19:dd:dd0:ec00:c25:c25:ec00:73a/1282c19:dd:dd0:ec00:c25:c25:ec00:73a
602c19:dd:dd0:ec00:c25:c25:ec00:73b/1282c19:dd:dd0:ec00:c25:c25:ec00:73b
612c19:dd:dd0:ec00:c25:c25:ec00:73c/1282c19:dd:dd0:ec00:c25:c25:ec00:73c
622c19:dd:dd0:ec00:c25:c25:ec00:73d/1282c19:dd:dd0:ec00:c25:c25:ec00:73d
632c19:dd:dd0:ec00:c25:c25:ec00:73e/1282c19:dd:dd0:ec00:c25:c25:ec00:73e
642c19:dd:dd0:ec00:c25:c25:ec00:73f/1282c19:dd:dd0:ec00:c25:c25:ec00:73f
652c19:dd:dd0:ec00:c25:c25:ec00:740/1282c19:dd:dd0:ec00:c25:c25:ec00:740
662c19:dd:dd0:ec00:c25:c25:ec00:741/1282c19:dd:dd0:ec00:c25:c25:ec00:741
672c19:dd:dd0:ec00:c25:c25:ec00:742/1282c19:dd:dd0:ec00:c25:c25:ec00:742
682c19:dd:dd0:ec00:c25:c25:ec00:743/1282c19:dd:dd0:ec00:c25:c25:ec00:743
692c19:dd:dd0:ec00:c25:c25:ec00:744/1282c19:dd:dd0:ec00:c25:c25:ec00:744
702c19:dd:dd0:ec00:c25:c25:ec00:745/1282c19:dd:dd0:ec00:c25:c25:ec00:745
712c19:dd:dd0:ec00:c25:c25:ec00:746/1282c19:dd:dd0:ec00:c25:c25:ec00:746
722c19:dd:dd0:ec00:c25:c25:ec00:747/1282c19:dd:dd0:ec00:c25:c25:ec00:747
732c19:dd:dd0:ec00:c25:c25:ec00:748/1282c19:dd:dd0:ec00:c25:c25:ec00:748
742c19:dd:dd0:ec00:c25:c25:ec00:749/1282c19:dd:dd0:ec00:c25:c25:ec00:749
752c19:dd:dd0:ec00:c25:c25:ec00:74a/1282c19:dd:dd0:ec00:c25:c25:ec00:74a
762c19:dd:dd0:ec00:c25:c25:ec00:74b/1282c19:dd:dd0:ec00:c25:c25:ec00:74b
772c19:dd:dd0:ec00:c25:c25:ec00:74c/1282c19:dd:dd0:ec00:c25:c25:ec00:74c
782c19:dd:dd0:ec00:c25:c25:ec00:74d/1282c19:dd:dd0:ec00:c25:c25:ec00:74d
792c19:dd:dd0:ec00:c25:c25:ec00:74e/1282c19:dd:dd0:ec00:c25:c25:ec00:74e
802c19:dd:dd0:ec00:c25:c25:ec00:74f/1282c19:dd:dd0:ec00:c25:c25:ec00:74f
812c19:dd:dd0:ec00:c25:c25:ec00:750/1282c19:dd:dd0:ec00:c25:c25:ec00:750
822c19:dd:dd0:ec00:c25:c25:ec00:751/1282c19:dd:dd0:ec00:c25:c25:ec00:751
832c19:dd:dd0:ec00:c25:c25:ec00:752/1282c19:dd:dd0:ec00:c25:c25:ec00:752
842c19:dd:dd0:ec00:c25:c25:ec00:753/1282c19:dd:dd0:ec00:c25:c25:ec00:753
852c19:dd:dd0:ec00:c25:c25:ec00:754/1282c19:dd:dd0:ec00:c25:c25:ec00:754
862c19:dd:dd0:ec00:c25:c25:ec00:755/1282c19:dd:dd0:ec00:c25:c25:ec00:755
872c19:dd:dd0:ec00:c25:c25:ec00:756/1282c19:dd:dd0:ec00:c25:c25:ec00:756
882c19:dd:dd0:ec00:c25:c25:ec00:757/1282c19:dd:dd0:ec00:c25:c25:ec00:757
892c19:dd:dd0:ec00:c25:c25:ec00:758/1282c19:dd:dd0:ec00:c25:c25:ec00:758
902c19:dd:dd0:ec00:c25:c25:ec00:759/1282c19:dd:dd0:ec00:c25:c25:ec00:759
912c19:dd:dd0:ec00:c25:c25:ec00:75a/1282c19:dd:dd0:ec00:c25:c25:ec00:75a
922c19:dd:dd0:ec00:c25:c25:ec00:75b/1282c19:dd:dd0:ec00:c25:c25:ec00:75b
932c19:dd:dd0:ec00:c25:c25:ec00:75c/1282c19:dd:dd0:ec00:c25:c25:ec00:75c
942c19:dd:dd0:ec00:c25:c25:ec00:75d/1282c19:dd:dd0:ec00:c25:c25:ec00:75d
952c19:dd:dd0:ec00:c25:c25:ec00:75e/1282c19:dd:dd0:ec00:c25:c25:ec00:75e
962c19:dd:dd0:ec00:c25:c25:ec00:75f/1282c19:dd:dd0:ec00:c25:c25:ec00:75f
972c19:dd:dd0:ec00:c25:c25:ec00:760/1282c19:dd:dd0:ec00:c25:c25:ec00:760
982c19:dd:dd0:ec00:c25:c25:ec00:761/1282c19:dd:dd0:ec00:c25:c25:ec00:761
992c19:dd:dd0:ec00:c25:c25:ec00:762/1282c19:dd:dd0:ec00:c25:c25:ec00:762
1002c19:dd:dd0:ec00:c25:c25:ec00:763/1282c19:dd:dd0:ec00:c25:c25:ec00:763
1012c19:dd:dd0:ec00:c25:c25:ec00:764/1282c19:dd:dd0:ec00:c25:c25:ec00:764
1022c19:dd:dd0:ec00:c25:c25:ec00:765/1282c19:dd:dd0:ec00:c25:c25:ec00:765
1032c19:dd:dd0:ec00:c25:c25:ec00:766/1282c19:dd:dd0:ec00:c25:c25:ec00:766
1042c19:dd:dd0:ec00:c25:c25:ec00:767/1282c19:dd:dd0:ec00:c25:c25:ec00:767
1052c19:dd:dd0:ec00:c25:c25:ec00:768/1282c19:dd:dd0:ec00:c25:c25:ec00:768
1062c19:dd:dd0:ec00:c25:c25:ec00:769/1282c19:dd:dd0:ec00:c25:c25:ec00:769
1072c19:dd:dd0:ec00:c25:c25:ec00:76a/1282c19:dd:dd0:ec00:c25:c25:ec00:76a
1082c19:dd:dd0:ec00:c25:c25:ec00:76b/1282c19:dd:dd0:ec00:c25:c25:ec00:76b
1092c19:dd:dd0:ec00:c25:c25:ec00:76c/1282c19:dd:dd0:ec00:c25:c25:ec00:76c
1102c19:dd:dd0:ec00:c25:c25:ec00:76d/1282c19:dd:dd0:ec00:c25:c25:ec00:76d
1112c19:dd:dd0:ec00:c25:c25:ec00:76e/1282c19:dd:dd0:ec00:c25:c25:ec00:76e
1122c19:dd:dd0:ec00:c25:c25:ec00:76f/1282c19:dd:dd0:ec00:c25:c25:ec00:76f
1132c19:dd:dd0:ec00:c25:c25:ec00:770/1282c19:dd:dd0:ec00:c25:c25:ec00:770
1142c19:dd:dd0:ec00:c25:c25:ec00:771/1282c19:dd:dd0:ec00:c25:c25:ec00:771
1152c19:dd:dd0:ec00:c25:c25:ec00:772/1282c19:dd:dd0:ec00:c25:c25:ec00:772
1162c19:dd:dd0:ec00:c25:c25:ec00:773/1282c19:dd:dd0:ec00:c25:c25:ec00:773
1172c19:dd:dd0:ec00:c25:c25:ec00:774/1282c19:dd:dd0:ec00:c25:c25:ec00:774
1182c19:dd:dd0:ec00:c25:c25:ec00:775/1282c19:dd:dd0:ec00:c25:c25:ec00:775
1192c19:dd:dd0:ec00:c25:c25:ec00:776/1282c19:dd:dd0:ec00:c25:c25:ec00:776
1202c19:dd:dd0:ec00:c25:c25:ec00:777/1282c19:dd:dd0:ec00:c25:c25:ec00:777
1212c19:dd:dd0:ec00:c25:c25:ec00:778/1282c19:dd:dd0:ec00:c25:c25:ec00:778
1222c19:dd:dd0:ec00:c25:c25:ec00:779/1282c19:dd:dd0:ec00:c25:c25:ec00:779
1232c19:dd:dd0:ec00:c25:c25:ec00:77a/1282c19:dd:dd0:ec00:c25:c25:ec00:77a
1242c19:dd:dd0:ec00:c25:c25:ec00:77b/1282c19:dd:dd0:ec00:c25:c25:ec00:77b
1252c19:dd:dd0:ec00:c25:c25:ec00:77c/1282c19:dd:dd0:ec00:c25:c25:ec00:77c
1262c19:dd:dd0:ec00:c25:c25:ec00:77d/1282c19:dd:dd0:ec00:c25:c25:ec00:77d
1272c19:dd:dd0:ec00:c25:c25:ec00:77e/1282c19:dd:dd0:ec00:c25:c25:ec00:77e
1282c19:dd:dd0:ec00:c25:c25:ec00:77f/1282c19:dd:dd0:ec00:c25:c25:ec00:77f
1292c19:dd:dd0:ec00:c25:c25:ec00:780/1282c19:dd:dd0:ec00:c25:c25:ec00:780
1302c19:dd:dd0:ec00:c25:c25:ec00:781/1282c19:dd:dd0:ec00:c25:c25:ec00:781
1312c19:dd:dd0:ec00:c25:c25:ec00:782/1282c19:dd:dd0:ec00:c25:c25:ec00:782
1322c19:dd:dd0:ec00:c25:c25:ec00:783/1282c19:dd:dd0:ec00:c25:c25:ec00:783
1332c19:dd:dd0:ec00:c25:c25:ec00:784/1282c19:dd:dd0:ec00:c25:c25:ec00:784
1342c19:dd:dd0:ec00:c25:c25:ec00:785/1282c19:dd:dd0:ec00:c25:c25:ec00:785
1352c19:dd:dd0:ec00:c25:c25:ec00:786/1282c19:dd:dd0:ec00:c25:c25:ec00:786
1362c19:dd:dd0:ec00:c25:c25:ec00:787/1282c19:dd:dd0:ec00:c25:c25:ec00:787
1372c19:dd:dd0:ec00:c25:c25:ec00:788/1282c19:dd:dd0:ec00:c25:c25:ec00:788
1382c19:dd:dd0:ec00:c25:c25:ec00:789/1282c19:dd:dd0:ec00:c25:c25:ec00:789
1392c19:dd:dd0:ec00:c25:c25:ec00:78a/1282c19:dd:dd0:ec00:c25:c25:ec00:78a
1402c19:dd:dd0:ec00:c25:c25:ec00:78b/1282c19:dd:dd0:ec00:c25:c25:ec00:78b
1412c19:dd:dd0:ec00:c25:c25:ec00:78c/1282c19:dd:dd0:ec00:c25:c25:ec00:78c
1422c19:dd:dd0:ec00:c25:c25:ec00:78d/1282c19:dd:dd0:ec00:c25:c25:ec00:78d
1432c19:dd:dd0:ec00:c25:c25:ec00:78e/1282c19:dd:dd0:ec00:c25:c25:ec00:78e
1442c19:dd:dd0:ec00:c25:c25:ec00:78f/1282c19:dd:dd0:ec00:c25:c25:ec00:78f
1452c19:dd:dd0:ec00:c25:c25:ec00:790/1282c19:dd:dd0:ec00:c25:c25:ec00:790
1462c19:dd:dd0:ec00:c25:c25:ec00:791/1282c19:dd:dd0:ec00:c25:c25:ec00:791
1472c19:dd:dd0:ec00:c25:c25:ec00:792/1282c19:dd:dd0:ec00:c25:c25:ec00:792
1482c19:dd:dd0:ec00:c25:c25:ec00:793/1282c19:dd:dd0:ec00:c25:c25:ec00:793
1492c19:dd:dd0:ec00:c25:c25:ec00:794/1282c19:dd:dd0:ec00:c25:c25:ec00:794
1502c19:dd:dd0:ec00:c25:c25:ec00:795/1282c19:dd:dd0:ec00:c25:c25:ec00:795
1512c19:dd:dd0:ec00:c25:c25:ec00:796/1282c19:dd:dd0:ec00:c25:c25:ec00:796
1522c19:dd:dd0:ec00:c25:c25:ec00:797/1282c19:dd:dd0:ec00:c25:c25:ec00:797
1532c19:dd:dd0:ec00:c25:c25:ec00:798/1282c19:dd:dd0:ec00:c25:c25:ec00:798
1542c19:dd:dd0:ec00:c25:c25:ec00:799/1282c19:dd:dd0:ec00:c25:c25:ec00:799
1552c19:dd:dd0:ec00:c25:c25:ec00:79a/1282c19:dd:dd0:ec00:c25:c25:ec00:79a
1562c19:dd:dd0:ec00:c25:c25:ec00:79b/1282c19:dd:dd0:ec00:c25:c25:ec00:79b
1572c19:dd:dd0:ec00:c25:c25:ec00:79c/1282c19:dd:dd0:ec00:c25:c25:ec00:79c
1582c19:dd:dd0:ec00:c25:c25:ec00:79d/1282c19:dd:dd0:ec00:c25:c25:ec00:79d
1592c19:dd:dd0:ec00:c25:c25:ec00:79e/1282c19:dd:dd0:ec00:c25:c25:ec00:79e
1602c19:dd:dd0:ec00:c25:c25:ec00:79f/1282c19:dd:dd0:ec00:c25:c25:ec00:79f
1612c19:dd:dd0:ec00:c25:c25:ec00:7a0/1282c19:dd:dd0:ec00:c25:c25:ec00:7a0
1622c19:dd:dd0:ec00:c25:c25:ec00:7a1/1282c19:dd:dd0:ec00:c25:c25:ec00:7a1
1632c19:dd:dd0:ec00:c25:c25:ec00:7a2/1282c19:dd:dd0:ec00:c25:c25:ec00:7a2
1642c19:dd:dd0:ec00:c25:c25:ec00:7a3/1282c19:dd:dd0:ec00:c25:c25:ec00:7a3
1652c19:dd:dd0:ec00:c25:c25:ec00:7a4/1282c19:dd:dd0:ec00:c25:c25:ec00:7a4
1662c19:dd:dd0:ec00:c25:c25:ec00:7a5/1282c19:dd:dd0:ec00:c25:c25:ec00:7a5
1672c19:dd:dd0:ec00:c25:c25:ec00:7a6/1282c19:dd:dd0:ec00:c25:c25:ec00:7a6
1682c19:dd:dd0:ec00:c25:c25:ec00:7a7/1282c19:dd:dd0:ec00:c25:c25:ec00:7a7
1692c19:dd:dd0:ec00:c25:c25:ec00:7a8/1282c19:dd:dd0:ec00:c25:c25:ec00:7a8
1702c19:dd:dd0:ec00:c25:c25:ec00:7a9/1282c19:dd:dd0:ec00:c25:c25:ec00:7a9
1712c19:dd:dd0:ec00:c25:c25:ec00:7aa/1282c19:dd:dd0:ec00:c25:c25:ec00:7aa
1722c19:dd:dd0:ec00:c25:c25:ec00:7ab/1282c19:dd:dd0:ec00:c25:c25:ec00:7ab
1732c19:dd:dd0:ec00:c25:c25:ec00:7ac/1282c19:dd:dd0:ec00:c25:c25:ec00:7ac
1742c19:dd:dd0:ec00:c25:c25:ec00:7ad/1282c19:dd:dd0:ec00:c25:c25:ec00:7ad
1752c19:dd:dd0:ec00:c25:c25:ec00:7ae/1282c19:dd:dd0:ec00:c25:c25:ec00:7ae
1762c19:dd:dd0:ec00:c25:c25:ec00:7af/1282c19:dd:dd0:ec00:c25:c25:ec00:7af
1772c19:dd:dd0:ec00:c25:c25:ec00:7b0/1282c19:dd:dd0:ec00:c25:c25:ec00:7b0
1782c19:dd:dd0:ec00:c25:c25:ec00:7b1/1282c19:dd:dd0:ec00:c25:c25:ec00:7b1
1792c19:dd:dd0:ec00:c25:c25:ec00:7b2/1282c19:dd:dd0:ec00:c25:c25:ec00:7b2
1802c19:dd:dd0:ec00:c25:c25:ec00:7b3/1282c19:dd:dd0:ec00:c25:c25:ec00:7b3
1812c19:dd:dd0:ec00:c25:c25:ec00:7b4/1282c19:dd:dd0:ec00:c25:c25:ec00:7b4
1822c19:dd:dd0:ec00:c25:c25:ec00:7b5/1282c19:dd:dd0:ec00:c25:c25:ec00:7b5
1832c19:dd:dd0:ec00:c25:c25:ec00:7b6/1282c19:dd:dd0:ec00:c25:c25:ec00:7b6
1842c19:dd:dd0:ec00:c25:c25:ec00:7b7/1282c19:dd:dd0:ec00:c25:c25:ec00:7b7
1852c19:dd:dd0:ec00:c25:c25:ec00:7b8/1282c19:dd:dd0:ec00:c25:c25:ec00:7b8
1862c19:dd:dd0:ec00:c25:c25:ec00:7b9/1282c19:dd:dd0:ec00:c25:c25:ec00:7b9
1872c19:dd:dd0:ec00:c25:c25:ec00:7ba/1282c19:dd:dd0:ec00:c25:c25:ec00:7ba
1882c19:dd:dd0:ec00:c25:c25:ec00:7bb/1282c19:dd:dd0:ec00:c25:c25:ec00:7bb
1892c19:dd:dd0:ec00:c25:c25:ec00:7bc/1282c19:dd:dd0:ec00:c25:c25:ec00:7bc
1902c19:dd:dd0:ec00:c25:c25:ec00:7bd/1282c19:dd:dd0:ec00:c25:c25:ec00:7bd
1912c19:dd:dd0:ec00:c25:c25:ec00:7be/1282c19:dd:dd0:ec00:c25:c25:ec00:7be
1922c19:dd:dd0:ec00:c25:c25:ec00:7bf/1282c19:dd:dd0:ec00:c25:c25:ec00:7bf
1932c19:dd:dd0:ec00:c25:c25:ec00:7c0/1282c19:dd:dd0:ec00:c25:c25:ec00:7c0
1942c19:dd:dd0:ec00:c25:c25:ec00:7c1/1282c19:dd:dd0:ec00:c25:c25:ec00:7c1
1952c19:dd:dd0:ec00:c25:c25:ec00:7c2/1282c19:dd:dd0:ec00:c25:c25:ec00:7c2
1962c19:dd:dd0:ec00:c25:c25:ec00:7c3/1282c19:dd:dd0:ec00:c25:c25:ec00:7c3
1972c19:dd:dd0:ec00:c25:c25:ec00:7c4/1282c19:dd:dd0:ec00:c25:c25:ec00:7c4
1982c19:dd:dd0:ec00:c25:c25:ec00:7c5/1282c19:dd:dd0:ec00:c25:c25:ec00:7c5
1992c19:dd:dd0:ec00:c25:c25:ec00:7c6/1282c19:dd:dd0:ec00:c25:c25:ec00:7c6
2002c19:dd:dd0:ec00:c25:c25:ec00:7c7/1282c19:dd:dd0:ec00:c25:c25:ec00:7c7
2012c19:dd:dd0:ec00:c25:c25:ec00:7c8/1282c19:dd:dd0:ec00:c25:c25:ec00:7c8
2022c19:dd:dd0:ec00:c25:c25:ec00:7c9/1282c19:dd:dd0:ec00:c25:c25:ec00:7c9
2032c19:dd:dd0:ec00:c25:c25:ec00:7ca/1282c19:dd:dd0:ec00:c25:c25:ec00:7ca
2042c19:dd:dd0:ec00:c25:c25:ec00:7cb/1282c19:dd:dd0:ec00:c25:c25:ec00:7cb
2052c19:dd:dd0:ec00:c25:c25:ec00:7cc/1282c19:dd:dd0:ec00:c25:c25:ec00:7cc
2062c19:dd:dd0:ec00:c25:c25:ec00:7cd/1282c19:dd:dd0:ec00:c25:c25:ec00:7cd
2072c19:dd:dd0:ec00:c25:c25:ec00:7ce/1282c19:dd:dd0:ec00:c25:c25:ec00:7ce
2082c19:dd:dd0:ec00:c25:c25:ec00:7cf/1282c19:dd:dd0:ec00:c25:c25:ec00:7cf
2092c19:dd:dd0:ec00:c25:c25:ec00:7d0/1282c19:dd:dd0:ec00:c25:c25:ec00:7d0
2102c19:dd:dd0:ec00:c25:c25:ec00:7d1/1282c19:dd:dd0:ec00:c25:c25:ec00:7d1
2112c19:dd:dd0:ec00:c25:c25:ec00:7d2/1282c19:dd:dd0:ec00:c25:c25:ec00:7d2
2122c19:dd:dd0:ec00:c25:c25:ec00:7d3/1282c19:dd:dd0:ec00:c25:c25:ec00:7d3
2132c19:dd:dd0:ec00:c25:c25:ec00:7d4/1282c19:dd:dd0:ec00:c25:c25:ec00:7d4
2142c19:dd:dd0:ec00:c25:c25:ec00:7d5/1282c19:dd:dd0:ec00:c25:c25:ec00:7d5
2152c19:dd:dd0:ec00:c25:c25:ec00:7d6/1282c19:dd:dd0:ec00:c25:c25:ec00:7d6
2162c19:dd:dd0:ec00:c25:c25:ec00:7d7/1282c19:dd:dd0:ec00:c25:c25:ec00:7d7
2172c19:dd:dd0:ec00:c25:c25:ec00:7d8/1282c19:dd:dd0:ec00:c25:c25:ec00:7d8
2182c19:dd:dd0:ec00:c25:c25:ec00:7d9/1282c19:dd:dd0:ec00:c25:c25:ec00:7d9
2192c19:dd:dd0:ec00:c25:c25:ec00:7da/1282c19:dd:dd0:ec00:c25:c25:ec00:7da
2202c19:dd:dd0:ec00:c25:c25:ec00:7db/1282c19:dd:dd0:ec00:c25:c25:ec00:7db
2212c19:dd:dd0:ec00:c25:c25:ec00:7dc/1282c19:dd:dd0:ec00:c25:c25:ec00:7dc
2222c19:dd:dd0:ec00:c25:c25:ec00:7dd/1282c19:dd:dd0:ec00:c25:c25:ec00:7dd
2232c19:dd:dd0:ec00:c25:c25:ec00:7de/1282c19:dd:dd0:ec00:c25:c25:ec00:7de
2242c19:dd:dd0:ec00:c25:c25:ec00:7df/1282c19:dd:dd0:ec00:c25:c25:ec00:7df
2252c19:dd:dd0:ec00:c25:c25:ec00:7e0/1282c19:dd:dd0:ec00:c25:c25:ec00:7e0
2262c19:dd:dd0:ec00:c25:c25:ec00:7e1/1282c19:dd:dd0:ec00:c25:c25:ec00:7e1
2272c19:dd:dd0:ec00:c25:c25:ec00:7e2/1282c19:dd:dd0:ec00:c25:c25:ec00:7e2
2282c19:dd:dd0:ec00:c25:c25:ec00:7e3/1282c19:dd:dd0:ec00:c25:c25:ec00:7e3
2292c19:dd:dd0:ec00:c25:c25:ec00:7e4/1282c19:dd:dd0:ec00:c25:c25:ec00:7e4
2302c19:dd:dd0:ec00:c25:c25:ec00:7e5/1282c19:dd:dd0:ec00:c25:c25:ec00:7e5
2312c19:dd:dd0:ec00:c25:c25:ec00:7e6/1282c19:dd:dd0:ec00:c25:c25:ec00:7e6
2322c19:dd:dd0:ec00:c25:c25:ec00:7e7/1282c19:dd:dd0:ec00:c25:c25:ec00:7e7
2332c19:dd:dd0:ec00:c25:c25:ec00:7e8/1282c19:dd:dd0:ec00:c25:c25:ec00:7e8
2342c19:dd:dd0:ec00:c25:c25:ec00:7e9/1282c19:dd:dd0:ec00:c25:c25:ec00:7e9
2352c19:dd:dd0:ec00:c25:c25:ec00:7ea/1282c19:dd:dd0:ec00:c25:c25:ec00:7ea
2362c19:dd:dd0:ec00:c25:c25:ec00:7eb/1282c19:dd:dd0:ec00:c25:c25:ec00:7eb
2372c19:dd:dd0:ec00:c25:c25:ec00:7ec/1282c19:dd:dd0:ec00:c25:c25:ec00:7ec
2382c19:dd:dd0:ec00:c25:c25:ec00:7ed/1282c19:dd:dd0:ec00:c25:c25:ec00:7ed
2392c19:dd:dd0:ec00:c25:c25:ec00:7ee/1282c19:dd:dd0:ec00:c25:c25:ec00:7ee
2402c19:dd:dd0:ec00:c25:c25:ec00:7ef/1282c19:dd:dd0:ec00:c25:c25:ec00:7ef
2412c19:dd:dd0:ec00:c25:c25:ec00:7f0/1282c19:dd:dd0:ec00:c25:c25:ec00:7f0
2422c19:dd:dd0:ec00:c25:c25:ec00:7f1/1282c19:dd:dd0:ec00:c25:c25:ec00:7f1
2432c19:dd:dd0:ec00:c25:c25:ec00:7f2/1282c19:dd:dd0:ec00:c25:c25:ec00:7f2
2442c19:dd:dd0:ec00:c25:c25:ec00:7f3/1282c19:dd:dd0:ec00:c25:c25:ec00:7f3
2452c19:dd:dd0:ec00:c25:c25:ec00:7f4/1282c19:dd:dd0:ec00:c25:c25:ec00:7f4
2462c19:dd:dd0:ec00:c25:c25:ec00:7f5/1282c19:dd:dd0:ec00:c25:c25:ec00:7f5
2472c19:dd:dd0:ec00:c25:c25:ec00:7f6/1282c19:dd:dd0:ec00:c25:c25:ec00:7f6
2482c19:dd:dd0:ec00:c25:c25:ec00:7f7/1282c19:dd:dd0:ec00:c25:c25:ec00:7f7
2492c19:dd:dd0:ec00:c25:c25:ec00:7f8/1282c19:dd:dd0:ec00:c25:c25:ec00:7f8
2502c19:dd:dd0:ec00:c25:c25:ec00:7f9/1282c19:dd:dd0:ec00:c25:c25:ec00:7f9
2512c19:dd:dd0:ec00:c25:c25:ec00:7fa/1282c19:dd:dd0:ec00:c25:c25:ec00:7fa
2522c19:dd:dd0:ec00:c25:c25:ec00:7fb/1282c19:dd:dd0:ec00:c25:c25:ec00:7fb
2532c19:dd:dd0:ec00:c25:c25:ec00:7fc/1282c19:dd:dd0:ec00:c25:c25:ec00:7fc
2542c19:dd:dd0:ec00:c25:c25:ec00:7fd/1282c19:dd:dd0:ec00:c25:c25:ec00:7fd
2552c19:dd:dd0:ec00:c25:c25:ec00:7fe/1282c19:dd:dd0:ec00:c25:c25:ec00:7fe
2562c19:dd:dd0:ec00:c25:c25:ec00:7ff/1282c19:dd:dd0:ec00:c25:c25:ec00:7ff

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.