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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:c25:94de:b700/120
First address
2c19:dd:d9:dd:c25:c25:94de:b700
Last address
2c19:dd:d9:dd:c25:c25:94de:b7ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:b700
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
7.b.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
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:94de:b700/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:b700/1282c19:dd:d9:dd:c25:c25:94de:b700
22c19:dd:d9:dd:c25:c25:94de:b701/1282c19:dd:d9:dd:c25:c25:94de:b701
32c19:dd:d9:dd:c25:c25:94de:b702/1282c19:dd:d9:dd:c25:c25:94de:b702
42c19:dd:d9:dd:c25:c25:94de:b703/1282c19:dd:d9:dd:c25:c25:94de:b703
52c19:dd:d9:dd:c25:c25:94de:b704/1282c19:dd:d9:dd:c25:c25:94de:b704
62c19:dd:d9:dd:c25:c25:94de:b705/1282c19:dd:d9:dd:c25:c25:94de:b705
72c19:dd:d9:dd:c25:c25:94de:b706/1282c19:dd:d9:dd:c25:c25:94de:b706
82c19:dd:d9:dd:c25:c25:94de:b707/1282c19:dd:d9:dd:c25:c25:94de:b707
92c19:dd:d9:dd:c25:c25:94de:b708/1282c19:dd:d9:dd:c25:c25:94de:b708
102c19:dd:d9:dd:c25:c25:94de:b709/1282c19:dd:d9:dd:c25:c25:94de:b709
112c19:dd:d9:dd:c25:c25:94de:b70a/1282c19:dd:d9:dd:c25:c25:94de:b70a
122c19:dd:d9:dd:c25:c25:94de:b70b/1282c19:dd:d9:dd:c25:c25:94de:b70b
132c19:dd:d9:dd:c25:c25:94de:b70c/1282c19:dd:d9:dd:c25:c25:94de:b70c
142c19:dd:d9:dd:c25:c25:94de:b70d/1282c19:dd:d9:dd:c25:c25:94de:b70d
152c19:dd:d9:dd:c25:c25:94de:b70e/1282c19:dd:d9:dd:c25:c25:94de:b70e
162c19:dd:d9:dd:c25:c25:94de:b70f/1282c19:dd:d9:dd:c25:c25:94de:b70f
172c19:dd:d9:dd:c25:c25:94de:b710/1282c19:dd:d9:dd:c25:c25:94de:b710
182c19:dd:d9:dd:c25:c25:94de:b711/1282c19:dd:d9:dd:c25:c25:94de:b711
192c19:dd:d9:dd:c25:c25:94de:b712/1282c19:dd:d9:dd:c25:c25:94de:b712
202c19:dd:d9:dd:c25:c25:94de:b713/1282c19:dd:d9:dd:c25:c25:94de:b713
212c19:dd:d9:dd:c25:c25:94de:b714/1282c19:dd:d9:dd:c25:c25:94de:b714
222c19:dd:d9:dd:c25:c25:94de:b715/1282c19:dd:d9:dd:c25:c25:94de:b715
232c19:dd:d9:dd:c25:c25:94de:b716/1282c19:dd:d9:dd:c25:c25:94de:b716
242c19:dd:d9:dd:c25:c25:94de:b717/1282c19:dd:d9:dd:c25:c25:94de:b717
252c19:dd:d9:dd:c25:c25:94de:b718/1282c19:dd:d9:dd:c25:c25:94de:b718
262c19:dd:d9:dd:c25:c25:94de:b719/1282c19:dd:d9:dd:c25:c25:94de:b719
272c19:dd:d9:dd:c25:c25:94de:b71a/1282c19:dd:d9:dd:c25:c25:94de:b71a
282c19:dd:d9:dd:c25:c25:94de:b71b/1282c19:dd:d9:dd:c25:c25:94de:b71b
292c19:dd:d9:dd:c25:c25:94de:b71c/1282c19:dd:d9:dd:c25:c25:94de:b71c
302c19:dd:d9:dd:c25:c25:94de:b71d/1282c19:dd:d9:dd:c25:c25:94de:b71d
312c19:dd:d9:dd:c25:c25:94de:b71e/1282c19:dd:d9:dd:c25:c25:94de:b71e
322c19:dd:d9:dd:c25:c25:94de:b71f/1282c19:dd:d9:dd:c25:c25:94de:b71f
332c19:dd:d9:dd:c25:c25:94de:b720/1282c19:dd:d9:dd:c25:c25:94de:b720
342c19:dd:d9:dd:c25:c25:94de:b721/1282c19:dd:d9:dd:c25:c25:94de:b721
352c19:dd:d9:dd:c25:c25:94de:b722/1282c19:dd:d9:dd:c25:c25:94de:b722
362c19:dd:d9:dd:c25:c25:94de:b723/1282c19:dd:d9:dd:c25:c25:94de:b723
372c19:dd:d9:dd:c25:c25:94de:b724/1282c19:dd:d9:dd:c25:c25:94de:b724
382c19:dd:d9:dd:c25:c25:94de:b725/1282c19:dd:d9:dd:c25:c25:94de:b725
392c19:dd:d9:dd:c25:c25:94de:b726/1282c19:dd:d9:dd:c25:c25:94de:b726
402c19:dd:d9:dd:c25:c25:94de:b727/1282c19:dd:d9:dd:c25:c25:94de:b727
412c19:dd:d9:dd:c25:c25:94de:b728/1282c19:dd:d9:dd:c25:c25:94de:b728
422c19:dd:d9:dd:c25:c25:94de:b729/1282c19:dd:d9:dd:c25:c25:94de:b729
432c19:dd:d9:dd:c25:c25:94de:b72a/1282c19:dd:d9:dd:c25:c25:94de:b72a
442c19:dd:d9:dd:c25:c25:94de:b72b/1282c19:dd:d9:dd:c25:c25:94de:b72b
452c19:dd:d9:dd:c25:c25:94de:b72c/1282c19:dd:d9:dd:c25:c25:94de:b72c
462c19:dd:d9:dd:c25:c25:94de:b72d/1282c19:dd:d9:dd:c25:c25:94de:b72d
472c19:dd:d9:dd:c25:c25:94de:b72e/1282c19:dd:d9:dd:c25:c25:94de:b72e
482c19:dd:d9:dd:c25:c25:94de:b72f/1282c19:dd:d9:dd:c25:c25:94de:b72f
492c19:dd:d9:dd:c25:c25:94de:b730/1282c19:dd:d9:dd:c25:c25:94de:b730
502c19:dd:d9:dd:c25:c25:94de:b731/1282c19:dd:d9:dd:c25:c25:94de:b731
512c19:dd:d9:dd:c25:c25:94de:b732/1282c19:dd:d9:dd:c25:c25:94de:b732
522c19:dd:d9:dd:c25:c25:94de:b733/1282c19:dd:d9:dd:c25:c25:94de:b733
532c19:dd:d9:dd:c25:c25:94de:b734/1282c19:dd:d9:dd:c25:c25:94de:b734
542c19:dd:d9:dd:c25:c25:94de:b735/1282c19:dd:d9:dd:c25:c25:94de:b735
552c19:dd:d9:dd:c25:c25:94de:b736/1282c19:dd:d9:dd:c25:c25:94de:b736
562c19:dd:d9:dd:c25:c25:94de:b737/1282c19:dd:d9:dd:c25:c25:94de:b737
572c19:dd:d9:dd:c25:c25:94de:b738/1282c19:dd:d9:dd:c25:c25:94de:b738
582c19:dd:d9:dd:c25:c25:94de:b739/1282c19:dd:d9:dd:c25:c25:94de:b739
592c19:dd:d9:dd:c25:c25:94de:b73a/1282c19:dd:d9:dd:c25:c25:94de:b73a
602c19:dd:d9:dd:c25:c25:94de:b73b/1282c19:dd:d9:dd:c25:c25:94de:b73b
612c19:dd:d9:dd:c25:c25:94de:b73c/1282c19:dd:d9:dd:c25:c25:94de:b73c
622c19:dd:d9:dd:c25:c25:94de:b73d/1282c19:dd:d9:dd:c25:c25:94de:b73d
632c19:dd:d9:dd:c25:c25:94de:b73e/1282c19:dd:d9:dd:c25:c25:94de:b73e
642c19:dd:d9:dd:c25:c25:94de:b73f/1282c19:dd:d9:dd:c25:c25:94de:b73f
652c19:dd:d9:dd:c25:c25:94de:b740/1282c19:dd:d9:dd:c25:c25:94de:b740
662c19:dd:d9:dd:c25:c25:94de:b741/1282c19:dd:d9:dd:c25:c25:94de:b741
672c19:dd:d9:dd:c25:c25:94de:b742/1282c19:dd:d9:dd:c25:c25:94de:b742
682c19:dd:d9:dd:c25:c25:94de:b743/1282c19:dd:d9:dd:c25:c25:94de:b743
692c19:dd:d9:dd:c25:c25:94de:b744/1282c19:dd:d9:dd:c25:c25:94de:b744
702c19:dd:d9:dd:c25:c25:94de:b745/1282c19:dd:d9:dd:c25:c25:94de:b745
712c19:dd:d9:dd:c25:c25:94de:b746/1282c19:dd:d9:dd:c25:c25:94de:b746
722c19:dd:d9:dd:c25:c25:94de:b747/1282c19:dd:d9:dd:c25:c25:94de:b747
732c19:dd:d9:dd:c25:c25:94de:b748/1282c19:dd:d9:dd:c25:c25:94de:b748
742c19:dd:d9:dd:c25:c25:94de:b749/1282c19:dd:d9:dd:c25:c25:94de:b749
752c19:dd:d9:dd:c25:c25:94de:b74a/1282c19:dd:d9:dd:c25:c25:94de:b74a
762c19:dd:d9:dd:c25:c25:94de:b74b/1282c19:dd:d9:dd:c25:c25:94de:b74b
772c19:dd:d9:dd:c25:c25:94de:b74c/1282c19:dd:d9:dd:c25:c25:94de:b74c
782c19:dd:d9:dd:c25:c25:94de:b74d/1282c19:dd:d9:dd:c25:c25:94de:b74d
792c19:dd:d9:dd:c25:c25:94de:b74e/1282c19:dd:d9:dd:c25:c25:94de:b74e
802c19:dd:d9:dd:c25:c25:94de:b74f/1282c19:dd:d9:dd:c25:c25:94de:b74f
812c19:dd:d9:dd:c25:c25:94de:b750/1282c19:dd:d9:dd:c25:c25:94de:b750
822c19:dd:d9:dd:c25:c25:94de:b751/1282c19:dd:d9:dd:c25:c25:94de:b751
832c19:dd:d9:dd:c25:c25:94de:b752/1282c19:dd:d9:dd:c25:c25:94de:b752
842c19:dd:d9:dd:c25:c25:94de:b753/1282c19:dd:d9:dd:c25:c25:94de:b753
852c19:dd:d9:dd:c25:c25:94de:b754/1282c19:dd:d9:dd:c25:c25:94de:b754
862c19:dd:d9:dd:c25:c25:94de:b755/1282c19:dd:d9:dd:c25:c25:94de:b755
872c19:dd:d9:dd:c25:c25:94de:b756/1282c19:dd:d9:dd:c25:c25:94de:b756
882c19:dd:d9:dd:c25:c25:94de:b757/1282c19:dd:d9:dd:c25:c25:94de:b757
892c19:dd:d9:dd:c25:c25:94de:b758/1282c19:dd:d9:dd:c25:c25:94de:b758
902c19:dd:d9:dd:c25:c25:94de:b759/1282c19:dd:d9:dd:c25:c25:94de:b759
912c19:dd:d9:dd:c25:c25:94de:b75a/1282c19:dd:d9:dd:c25:c25:94de:b75a
922c19:dd:d9:dd:c25:c25:94de:b75b/1282c19:dd:d9:dd:c25:c25:94de:b75b
932c19:dd:d9:dd:c25:c25:94de:b75c/1282c19:dd:d9:dd:c25:c25:94de:b75c
942c19:dd:d9:dd:c25:c25:94de:b75d/1282c19:dd:d9:dd:c25:c25:94de:b75d
952c19:dd:d9:dd:c25:c25:94de:b75e/1282c19:dd:d9:dd:c25:c25:94de:b75e
962c19:dd:d9:dd:c25:c25:94de:b75f/1282c19:dd:d9:dd:c25:c25:94de:b75f
972c19:dd:d9:dd:c25:c25:94de:b760/1282c19:dd:d9:dd:c25:c25:94de:b760
982c19:dd:d9:dd:c25:c25:94de:b761/1282c19:dd:d9:dd:c25:c25:94de:b761
992c19:dd:d9:dd:c25:c25:94de:b762/1282c19:dd:d9:dd:c25:c25:94de:b762
1002c19:dd:d9:dd:c25:c25:94de:b763/1282c19:dd:d9:dd:c25:c25:94de:b763
1012c19:dd:d9:dd:c25:c25:94de:b764/1282c19:dd:d9:dd:c25:c25:94de:b764
1022c19:dd:d9:dd:c25:c25:94de:b765/1282c19:dd:d9:dd:c25:c25:94de:b765
1032c19:dd:d9:dd:c25:c25:94de:b766/1282c19:dd:d9:dd:c25:c25:94de:b766
1042c19:dd:d9:dd:c25:c25:94de:b767/1282c19:dd:d9:dd:c25:c25:94de:b767
1052c19:dd:d9:dd:c25:c25:94de:b768/1282c19:dd:d9:dd:c25:c25:94de:b768
1062c19:dd:d9:dd:c25:c25:94de:b769/1282c19:dd:d9:dd:c25:c25:94de:b769
1072c19:dd:d9:dd:c25:c25:94de:b76a/1282c19:dd:d9:dd:c25:c25:94de:b76a
1082c19:dd:d9:dd:c25:c25:94de:b76b/1282c19:dd:d9:dd:c25:c25:94de:b76b
1092c19:dd:d9:dd:c25:c25:94de:b76c/1282c19:dd:d9:dd:c25:c25:94de:b76c
1102c19:dd:d9:dd:c25:c25:94de:b76d/1282c19:dd:d9:dd:c25:c25:94de:b76d
1112c19:dd:d9:dd:c25:c25:94de:b76e/1282c19:dd:d9:dd:c25:c25:94de:b76e
1122c19:dd:d9:dd:c25:c25:94de:b76f/1282c19:dd:d9:dd:c25:c25:94de:b76f
1132c19:dd:d9:dd:c25:c25:94de:b770/1282c19:dd:d9:dd:c25:c25:94de:b770
1142c19:dd:d9:dd:c25:c25:94de:b771/1282c19:dd:d9:dd:c25:c25:94de:b771
1152c19:dd:d9:dd:c25:c25:94de:b772/1282c19:dd:d9:dd:c25:c25:94de:b772
1162c19:dd:d9:dd:c25:c25:94de:b773/1282c19:dd:d9:dd:c25:c25:94de:b773
1172c19:dd:d9:dd:c25:c25:94de:b774/1282c19:dd:d9:dd:c25:c25:94de:b774
1182c19:dd:d9:dd:c25:c25:94de:b775/1282c19:dd:d9:dd:c25:c25:94de:b775
1192c19:dd:d9:dd:c25:c25:94de:b776/1282c19:dd:d9:dd:c25:c25:94de:b776
1202c19:dd:d9:dd:c25:c25:94de:b777/1282c19:dd:d9:dd:c25:c25:94de:b777
1212c19:dd:d9:dd:c25:c25:94de:b778/1282c19:dd:d9:dd:c25:c25:94de:b778
1222c19:dd:d9:dd:c25:c25:94de:b779/1282c19:dd:d9:dd:c25:c25:94de:b779
1232c19:dd:d9:dd:c25:c25:94de:b77a/1282c19:dd:d9:dd:c25:c25:94de:b77a
1242c19:dd:d9:dd:c25:c25:94de:b77b/1282c19:dd:d9:dd:c25:c25:94de:b77b
1252c19:dd:d9:dd:c25:c25:94de:b77c/1282c19:dd:d9:dd:c25:c25:94de:b77c
1262c19:dd:d9:dd:c25:c25:94de:b77d/1282c19:dd:d9:dd:c25:c25:94de:b77d
1272c19:dd:d9:dd:c25:c25:94de:b77e/1282c19:dd:d9:dd:c25:c25:94de:b77e
1282c19:dd:d9:dd:c25:c25:94de:b77f/1282c19:dd:d9:dd:c25:c25:94de:b77f
1292c19:dd:d9:dd:c25:c25:94de:b780/1282c19:dd:d9:dd:c25:c25:94de:b780
1302c19:dd:d9:dd:c25:c25:94de:b781/1282c19:dd:d9:dd:c25:c25:94de:b781
1312c19:dd:d9:dd:c25:c25:94de:b782/1282c19:dd:d9:dd:c25:c25:94de:b782
1322c19:dd:d9:dd:c25:c25:94de:b783/1282c19:dd:d9:dd:c25:c25:94de:b783
1332c19:dd:d9:dd:c25:c25:94de:b784/1282c19:dd:d9:dd:c25:c25:94de:b784
1342c19:dd:d9:dd:c25:c25:94de:b785/1282c19:dd:d9:dd:c25:c25:94de:b785
1352c19:dd:d9:dd:c25:c25:94de:b786/1282c19:dd:d9:dd:c25:c25:94de:b786
1362c19:dd:d9:dd:c25:c25:94de:b787/1282c19:dd:d9:dd:c25:c25:94de:b787
1372c19:dd:d9:dd:c25:c25:94de:b788/1282c19:dd:d9:dd:c25:c25:94de:b788
1382c19:dd:d9:dd:c25:c25:94de:b789/1282c19:dd:d9:dd:c25:c25:94de:b789
1392c19:dd:d9:dd:c25:c25:94de:b78a/1282c19:dd:d9:dd:c25:c25:94de:b78a
1402c19:dd:d9:dd:c25:c25:94de:b78b/1282c19:dd:d9:dd:c25:c25:94de:b78b
1412c19:dd:d9:dd:c25:c25:94de:b78c/1282c19:dd:d9:dd:c25:c25:94de:b78c
1422c19:dd:d9:dd:c25:c25:94de:b78d/1282c19:dd:d9:dd:c25:c25:94de:b78d
1432c19:dd:d9:dd:c25:c25:94de:b78e/1282c19:dd:d9:dd:c25:c25:94de:b78e
1442c19:dd:d9:dd:c25:c25:94de:b78f/1282c19:dd:d9:dd:c25:c25:94de:b78f
1452c19:dd:d9:dd:c25:c25:94de:b790/1282c19:dd:d9:dd:c25:c25:94de:b790
1462c19:dd:d9:dd:c25:c25:94de:b791/1282c19:dd:d9:dd:c25:c25:94de:b791
1472c19:dd:d9:dd:c25:c25:94de:b792/1282c19:dd:d9:dd:c25:c25:94de:b792
1482c19:dd:d9:dd:c25:c25:94de:b793/1282c19:dd:d9:dd:c25:c25:94de:b793
1492c19:dd:d9:dd:c25:c25:94de:b794/1282c19:dd:d9:dd:c25:c25:94de:b794
1502c19:dd:d9:dd:c25:c25:94de:b795/1282c19:dd:d9:dd:c25:c25:94de:b795
1512c19:dd:d9:dd:c25:c25:94de:b796/1282c19:dd:d9:dd:c25:c25:94de:b796
1522c19:dd:d9:dd:c25:c25:94de:b797/1282c19:dd:d9:dd:c25:c25:94de:b797
1532c19:dd:d9:dd:c25:c25:94de:b798/1282c19:dd:d9:dd:c25:c25:94de:b798
1542c19:dd:d9:dd:c25:c25:94de:b799/1282c19:dd:d9:dd:c25:c25:94de:b799
1552c19:dd:d9:dd:c25:c25:94de:b79a/1282c19:dd:d9:dd:c25:c25:94de:b79a
1562c19:dd:d9:dd:c25:c25:94de:b79b/1282c19:dd:d9:dd:c25:c25:94de:b79b
1572c19:dd:d9:dd:c25:c25:94de:b79c/1282c19:dd:d9:dd:c25:c25:94de:b79c
1582c19:dd:d9:dd:c25:c25:94de:b79d/1282c19:dd:d9:dd:c25:c25:94de:b79d
1592c19:dd:d9:dd:c25:c25:94de:b79e/1282c19:dd:d9:dd:c25:c25:94de:b79e
1602c19:dd:d9:dd:c25:c25:94de:b79f/1282c19:dd:d9:dd:c25:c25:94de:b79f
1612c19:dd:d9:dd:c25:c25:94de:b7a0/1282c19:dd:d9:dd:c25:c25:94de:b7a0
1622c19:dd:d9:dd:c25:c25:94de:b7a1/1282c19:dd:d9:dd:c25:c25:94de:b7a1
1632c19:dd:d9:dd:c25:c25:94de:b7a2/1282c19:dd:d9:dd:c25:c25:94de:b7a2
1642c19:dd:d9:dd:c25:c25:94de:b7a3/1282c19:dd:d9:dd:c25:c25:94de:b7a3
1652c19:dd:d9:dd:c25:c25:94de:b7a4/1282c19:dd:d9:dd:c25:c25:94de:b7a4
1662c19:dd:d9:dd:c25:c25:94de:b7a5/1282c19:dd:d9:dd:c25:c25:94de:b7a5
1672c19:dd:d9:dd:c25:c25:94de:b7a6/1282c19:dd:d9:dd:c25:c25:94de:b7a6
1682c19:dd:d9:dd:c25:c25:94de:b7a7/1282c19:dd:d9:dd:c25:c25:94de:b7a7
1692c19:dd:d9:dd:c25:c25:94de:b7a8/1282c19:dd:d9:dd:c25:c25:94de:b7a8
1702c19:dd:d9:dd:c25:c25:94de:b7a9/1282c19:dd:d9:dd:c25:c25:94de:b7a9
1712c19:dd:d9:dd:c25:c25:94de:b7aa/1282c19:dd:d9:dd:c25:c25:94de:b7aa
1722c19:dd:d9:dd:c25:c25:94de:b7ab/1282c19:dd:d9:dd:c25:c25:94de:b7ab
1732c19:dd:d9:dd:c25:c25:94de:b7ac/1282c19:dd:d9:dd:c25:c25:94de:b7ac
1742c19:dd:d9:dd:c25:c25:94de:b7ad/1282c19:dd:d9:dd:c25:c25:94de:b7ad
1752c19:dd:d9:dd:c25:c25:94de:b7ae/1282c19:dd:d9:dd:c25:c25:94de:b7ae
1762c19:dd:d9:dd:c25:c25:94de:b7af/1282c19:dd:d9:dd:c25:c25:94de:b7af
1772c19:dd:d9:dd:c25:c25:94de:b7b0/1282c19:dd:d9:dd:c25:c25:94de:b7b0
1782c19:dd:d9:dd:c25:c25:94de:b7b1/1282c19:dd:d9:dd:c25:c25:94de:b7b1
1792c19:dd:d9:dd:c25:c25:94de:b7b2/1282c19:dd:d9:dd:c25:c25:94de:b7b2
1802c19:dd:d9:dd:c25:c25:94de:b7b3/1282c19:dd:d9:dd:c25:c25:94de:b7b3
1812c19:dd:d9:dd:c25:c25:94de:b7b4/1282c19:dd:d9:dd:c25:c25:94de:b7b4
1822c19:dd:d9:dd:c25:c25:94de:b7b5/1282c19:dd:d9:dd:c25:c25:94de:b7b5
1832c19:dd:d9:dd:c25:c25:94de:b7b6/1282c19:dd:d9:dd:c25:c25:94de:b7b6
1842c19:dd:d9:dd:c25:c25:94de:b7b7/1282c19:dd:d9:dd:c25:c25:94de:b7b7
1852c19:dd:d9:dd:c25:c25:94de:b7b8/1282c19:dd:d9:dd:c25:c25:94de:b7b8
1862c19:dd:d9:dd:c25:c25:94de:b7b9/1282c19:dd:d9:dd:c25:c25:94de:b7b9
1872c19:dd:d9:dd:c25:c25:94de:b7ba/1282c19:dd:d9:dd:c25:c25:94de:b7ba
1882c19:dd:d9:dd:c25:c25:94de:b7bb/1282c19:dd:d9:dd:c25:c25:94de:b7bb
1892c19:dd:d9:dd:c25:c25:94de:b7bc/1282c19:dd:d9:dd:c25:c25:94de:b7bc
1902c19:dd:d9:dd:c25:c25:94de:b7bd/1282c19:dd:d9:dd:c25:c25:94de:b7bd
1912c19:dd:d9:dd:c25:c25:94de:b7be/1282c19:dd:d9:dd:c25:c25:94de:b7be
1922c19:dd:d9:dd:c25:c25:94de:b7bf/1282c19:dd:d9:dd:c25:c25:94de:b7bf
1932c19:dd:d9:dd:c25:c25:94de:b7c0/1282c19:dd:d9:dd:c25:c25:94de:b7c0
1942c19:dd:d9:dd:c25:c25:94de:b7c1/1282c19:dd:d9:dd:c25:c25:94de:b7c1
1952c19:dd:d9:dd:c25:c25:94de:b7c2/1282c19:dd:d9:dd:c25:c25:94de:b7c2
1962c19:dd:d9:dd:c25:c25:94de:b7c3/1282c19:dd:d9:dd:c25:c25:94de:b7c3
1972c19:dd:d9:dd:c25:c25:94de:b7c4/1282c19:dd:d9:dd:c25:c25:94de:b7c4
1982c19:dd:d9:dd:c25:c25:94de:b7c5/1282c19:dd:d9:dd:c25:c25:94de:b7c5
1992c19:dd:d9:dd:c25:c25:94de:b7c6/1282c19:dd:d9:dd:c25:c25:94de:b7c6
2002c19:dd:d9:dd:c25:c25:94de:b7c7/1282c19:dd:d9:dd:c25:c25:94de:b7c7
2012c19:dd:d9:dd:c25:c25:94de:b7c8/1282c19:dd:d9:dd:c25:c25:94de:b7c8
2022c19:dd:d9:dd:c25:c25:94de:b7c9/1282c19:dd:d9:dd:c25:c25:94de:b7c9
2032c19:dd:d9:dd:c25:c25:94de:b7ca/1282c19:dd:d9:dd:c25:c25:94de:b7ca
2042c19:dd:d9:dd:c25:c25:94de:b7cb/1282c19:dd:d9:dd:c25:c25:94de:b7cb
2052c19:dd:d9:dd:c25:c25:94de:b7cc/1282c19:dd:d9:dd:c25:c25:94de:b7cc
2062c19:dd:d9:dd:c25:c25:94de:b7cd/1282c19:dd:d9:dd:c25:c25:94de:b7cd
2072c19:dd:d9:dd:c25:c25:94de:b7ce/1282c19:dd:d9:dd:c25:c25:94de:b7ce
2082c19:dd:d9:dd:c25:c25:94de:b7cf/1282c19:dd:d9:dd:c25:c25:94de:b7cf
2092c19:dd:d9:dd:c25:c25:94de:b7d0/1282c19:dd:d9:dd:c25:c25:94de:b7d0
2102c19:dd:d9:dd:c25:c25:94de:b7d1/1282c19:dd:d9:dd:c25:c25:94de:b7d1
2112c19:dd:d9:dd:c25:c25:94de:b7d2/1282c19:dd:d9:dd:c25:c25:94de:b7d2
2122c19:dd:d9:dd:c25:c25:94de:b7d3/1282c19:dd:d9:dd:c25:c25:94de:b7d3
2132c19:dd:d9:dd:c25:c25:94de:b7d4/1282c19:dd:d9:dd:c25:c25:94de:b7d4
2142c19:dd:d9:dd:c25:c25:94de:b7d5/1282c19:dd:d9:dd:c25:c25:94de:b7d5
2152c19:dd:d9:dd:c25:c25:94de:b7d6/1282c19:dd:d9:dd:c25:c25:94de:b7d6
2162c19:dd:d9:dd:c25:c25:94de:b7d7/1282c19:dd:d9:dd:c25:c25:94de:b7d7
2172c19:dd:d9:dd:c25:c25:94de:b7d8/1282c19:dd:d9:dd:c25:c25:94de:b7d8
2182c19:dd:d9:dd:c25:c25:94de:b7d9/1282c19:dd:d9:dd:c25:c25:94de:b7d9
2192c19:dd:d9:dd:c25:c25:94de:b7da/1282c19:dd:d9:dd:c25:c25:94de:b7da
2202c19:dd:d9:dd:c25:c25:94de:b7db/1282c19:dd:d9:dd:c25:c25:94de:b7db
2212c19:dd:d9:dd:c25:c25:94de:b7dc/1282c19:dd:d9:dd:c25:c25:94de:b7dc
2222c19:dd:d9:dd:c25:c25:94de:b7dd/1282c19:dd:d9:dd:c25:c25:94de:b7dd
2232c19:dd:d9:dd:c25:c25:94de:b7de/1282c19:dd:d9:dd:c25:c25:94de:b7de
2242c19:dd:d9:dd:c25:c25:94de:b7df/1282c19:dd:d9:dd:c25:c25:94de:b7df
2252c19:dd:d9:dd:c25:c25:94de:b7e0/1282c19:dd:d9:dd:c25:c25:94de:b7e0
2262c19:dd:d9:dd:c25:c25:94de:b7e1/1282c19:dd:d9:dd:c25:c25:94de:b7e1
2272c19:dd:d9:dd:c25:c25:94de:b7e2/1282c19:dd:d9:dd:c25:c25:94de:b7e2
2282c19:dd:d9:dd:c25:c25:94de:b7e3/1282c19:dd:d9:dd:c25:c25:94de:b7e3
2292c19:dd:d9:dd:c25:c25:94de:b7e4/1282c19:dd:d9:dd:c25:c25:94de:b7e4
2302c19:dd:d9:dd:c25:c25:94de:b7e5/1282c19:dd:d9:dd:c25:c25:94de:b7e5
2312c19:dd:d9:dd:c25:c25:94de:b7e6/1282c19:dd:d9:dd:c25:c25:94de:b7e6
2322c19:dd:d9:dd:c25:c25:94de:b7e7/1282c19:dd:d9:dd:c25:c25:94de:b7e7
2332c19:dd:d9:dd:c25:c25:94de:b7e8/1282c19:dd:d9:dd:c25:c25:94de:b7e8
2342c19:dd:d9:dd:c25:c25:94de:b7e9/1282c19:dd:d9:dd:c25:c25:94de:b7e9
2352c19:dd:d9:dd:c25:c25:94de:b7ea/1282c19:dd:d9:dd:c25:c25:94de:b7ea
2362c19:dd:d9:dd:c25:c25:94de:b7eb/1282c19:dd:d9:dd:c25:c25:94de:b7eb
2372c19:dd:d9:dd:c25:c25:94de:b7ec/1282c19:dd:d9:dd:c25:c25:94de:b7ec
2382c19:dd:d9:dd:c25:c25:94de:b7ed/1282c19:dd:d9:dd:c25:c25:94de:b7ed
2392c19:dd:d9:dd:c25:c25:94de:b7ee/1282c19:dd:d9:dd:c25:c25:94de:b7ee
2402c19:dd:d9:dd:c25:c25:94de:b7ef/1282c19:dd:d9:dd:c25:c25:94de:b7ef
2412c19:dd:d9:dd:c25:c25:94de:b7f0/1282c19:dd:d9:dd:c25:c25:94de:b7f0
2422c19:dd:d9:dd:c25:c25:94de:b7f1/1282c19:dd:d9:dd:c25:c25:94de:b7f1
2432c19:dd:d9:dd:c25:c25:94de:b7f2/1282c19:dd:d9:dd:c25:c25:94de:b7f2
2442c19:dd:d9:dd:c25:c25:94de:b7f3/1282c19:dd:d9:dd:c25:c25:94de:b7f3
2452c19:dd:d9:dd:c25:c25:94de:b7f4/1282c19:dd:d9:dd:c25:c25:94de:b7f4
2462c19:dd:d9:dd:c25:c25:94de:b7f5/1282c19:dd:d9:dd:c25:c25:94de:b7f5
2472c19:dd:d9:dd:c25:c25:94de:b7f6/1282c19:dd:d9:dd:c25:c25:94de:b7f6
2482c19:dd:d9:dd:c25:c25:94de:b7f7/1282c19:dd:d9:dd:c25:c25:94de:b7f7
2492c19:dd:d9:dd:c25:c25:94de:b7f8/1282c19:dd:d9:dd:c25:c25:94de:b7f8
2502c19:dd:d9:dd:c25:c25:94de:b7f9/1282c19:dd:d9:dd:c25:c25:94de:b7f9
2512c19:dd:d9:dd:c25:c25:94de:b7fa/1282c19:dd:d9:dd:c25:c25:94de:b7fa
2522c19:dd:d9:dd:c25:c25:94de:b7fb/1282c19:dd:d9:dd:c25:c25:94de:b7fb
2532c19:dd:d9:dd:c25:c25:94de:b7fc/1282c19:dd:d9:dd:c25:c25:94de:b7fc
2542c19:dd:d9:dd:c25:c25:94de:b7fd/1282c19:dd:d9:dd:c25:c25:94de:b7fd
2552c19:dd:d9:dd:c25:c25:94de:b7fe/1282c19:dd:d9:dd:c25:c25:94de:b7fe
2562c19:dd:d9:dd:c25:c25:94de:b7ff/1282c19:dd:d9:dd:c25:c25:94de:b7ff

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.