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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:dd0:ec00:5700/120
First address
2c19:dd:d9:dd:c25:dd0:ec00:5700
Last address
2c19:dd:d9:dd:c25:dd0:ec00:57ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0dd0:ec00:5700
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
7.5.0.0.c.e.0.d.d.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:dd0:ec00:5700/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:dd0:ec00:5700/1282c19:dd:d9:dd:c25:dd0:ec00:5700
22c19:dd:d9:dd:c25:dd0:ec00:5701/1282c19:dd:d9:dd:c25:dd0:ec00:5701
32c19:dd:d9:dd:c25:dd0:ec00:5702/1282c19:dd:d9:dd:c25:dd0:ec00:5702
42c19:dd:d9:dd:c25:dd0:ec00:5703/1282c19:dd:d9:dd:c25:dd0:ec00:5703
52c19:dd:d9:dd:c25:dd0:ec00:5704/1282c19:dd:d9:dd:c25:dd0:ec00:5704
62c19:dd:d9:dd:c25:dd0:ec00:5705/1282c19:dd:d9:dd:c25:dd0:ec00:5705
72c19:dd:d9:dd:c25:dd0:ec00:5706/1282c19:dd:d9:dd:c25:dd0:ec00:5706
82c19:dd:d9:dd:c25:dd0:ec00:5707/1282c19:dd:d9:dd:c25:dd0:ec00:5707
92c19:dd:d9:dd:c25:dd0:ec00:5708/1282c19:dd:d9:dd:c25:dd0:ec00:5708
102c19:dd:d9:dd:c25:dd0:ec00:5709/1282c19:dd:d9:dd:c25:dd0:ec00:5709
112c19:dd:d9:dd:c25:dd0:ec00:570a/1282c19:dd:d9:dd:c25:dd0:ec00:570a
122c19:dd:d9:dd:c25:dd0:ec00:570b/1282c19:dd:d9:dd:c25:dd0:ec00:570b
132c19:dd:d9:dd:c25:dd0:ec00:570c/1282c19:dd:d9:dd:c25:dd0:ec00:570c
142c19:dd:d9:dd:c25:dd0:ec00:570d/1282c19:dd:d9:dd:c25:dd0:ec00:570d
152c19:dd:d9:dd:c25:dd0:ec00:570e/1282c19:dd:d9:dd:c25:dd0:ec00:570e
162c19:dd:d9:dd:c25:dd0:ec00:570f/1282c19:dd:d9:dd:c25:dd0:ec00:570f
172c19:dd:d9:dd:c25:dd0:ec00:5710/1282c19:dd:d9:dd:c25:dd0:ec00:5710
182c19:dd:d9:dd:c25:dd0:ec00:5711/1282c19:dd:d9:dd:c25:dd0:ec00:5711
192c19:dd:d9:dd:c25:dd0:ec00:5712/1282c19:dd:d9:dd:c25:dd0:ec00:5712
202c19:dd:d9:dd:c25:dd0:ec00:5713/1282c19:dd:d9:dd:c25:dd0:ec00:5713
212c19:dd:d9:dd:c25:dd0:ec00:5714/1282c19:dd:d9:dd:c25:dd0:ec00:5714
222c19:dd:d9:dd:c25:dd0:ec00:5715/1282c19:dd:d9:dd:c25:dd0:ec00:5715
232c19:dd:d9:dd:c25:dd0:ec00:5716/1282c19:dd:d9:dd:c25:dd0:ec00:5716
242c19:dd:d9:dd:c25:dd0:ec00:5717/1282c19:dd:d9:dd:c25:dd0:ec00:5717
252c19:dd:d9:dd:c25:dd0:ec00:5718/1282c19:dd:d9:dd:c25:dd0:ec00:5718
262c19:dd:d9:dd:c25:dd0:ec00:5719/1282c19:dd:d9:dd:c25:dd0:ec00:5719
272c19:dd:d9:dd:c25:dd0:ec00:571a/1282c19:dd:d9:dd:c25:dd0:ec00:571a
282c19:dd:d9:dd:c25:dd0:ec00:571b/1282c19:dd:d9:dd:c25:dd0:ec00:571b
292c19:dd:d9:dd:c25:dd0:ec00:571c/1282c19:dd:d9:dd:c25:dd0:ec00:571c
302c19:dd:d9:dd:c25:dd0:ec00:571d/1282c19:dd:d9:dd:c25:dd0:ec00:571d
312c19:dd:d9:dd:c25:dd0:ec00:571e/1282c19:dd:d9:dd:c25:dd0:ec00:571e
322c19:dd:d9:dd:c25:dd0:ec00:571f/1282c19:dd:d9:dd:c25:dd0:ec00:571f
332c19:dd:d9:dd:c25:dd0:ec00:5720/1282c19:dd:d9:dd:c25:dd0:ec00:5720
342c19:dd:d9:dd:c25:dd0:ec00:5721/1282c19:dd:d9:dd:c25:dd0:ec00:5721
352c19:dd:d9:dd:c25:dd0:ec00:5722/1282c19:dd:d9:dd:c25:dd0:ec00:5722
362c19:dd:d9:dd:c25:dd0:ec00:5723/1282c19:dd:d9:dd:c25:dd0:ec00:5723
372c19:dd:d9:dd:c25:dd0:ec00:5724/1282c19:dd:d9:dd:c25:dd0:ec00:5724
382c19:dd:d9:dd:c25:dd0:ec00:5725/1282c19:dd:d9:dd:c25:dd0:ec00:5725
392c19:dd:d9:dd:c25:dd0:ec00:5726/1282c19:dd:d9:dd:c25:dd0:ec00:5726
402c19:dd:d9:dd:c25:dd0:ec00:5727/1282c19:dd:d9:dd:c25:dd0:ec00:5727
412c19:dd:d9:dd:c25:dd0:ec00:5728/1282c19:dd:d9:dd:c25:dd0:ec00:5728
422c19:dd:d9:dd:c25:dd0:ec00:5729/1282c19:dd:d9:dd:c25:dd0:ec00:5729
432c19:dd:d9:dd:c25:dd0:ec00:572a/1282c19:dd:d9:dd:c25:dd0:ec00:572a
442c19:dd:d9:dd:c25:dd0:ec00:572b/1282c19:dd:d9:dd:c25:dd0:ec00:572b
452c19:dd:d9:dd:c25:dd0:ec00:572c/1282c19:dd:d9:dd:c25:dd0:ec00:572c
462c19:dd:d9:dd:c25:dd0:ec00:572d/1282c19:dd:d9:dd:c25:dd0:ec00:572d
472c19:dd:d9:dd:c25:dd0:ec00:572e/1282c19:dd:d9:dd:c25:dd0:ec00:572e
482c19:dd:d9:dd:c25:dd0:ec00:572f/1282c19:dd:d9:dd:c25:dd0:ec00:572f
492c19:dd:d9:dd:c25:dd0:ec00:5730/1282c19:dd:d9:dd:c25:dd0:ec00:5730
502c19:dd:d9:dd:c25:dd0:ec00:5731/1282c19:dd:d9:dd:c25:dd0:ec00:5731
512c19:dd:d9:dd:c25:dd0:ec00:5732/1282c19:dd:d9:dd:c25:dd0:ec00:5732
522c19:dd:d9:dd:c25:dd0:ec00:5733/1282c19:dd:d9:dd:c25:dd0:ec00:5733
532c19:dd:d9:dd:c25:dd0:ec00:5734/1282c19:dd:d9:dd:c25:dd0:ec00:5734
542c19:dd:d9:dd:c25:dd0:ec00:5735/1282c19:dd:d9:dd:c25:dd0:ec00:5735
552c19:dd:d9:dd:c25:dd0:ec00:5736/1282c19:dd:d9:dd:c25:dd0:ec00:5736
562c19:dd:d9:dd:c25:dd0:ec00:5737/1282c19:dd:d9:dd:c25:dd0:ec00:5737
572c19:dd:d9:dd:c25:dd0:ec00:5738/1282c19:dd:d9:dd:c25:dd0:ec00:5738
582c19:dd:d9:dd:c25:dd0:ec00:5739/1282c19:dd:d9:dd:c25:dd0:ec00:5739
592c19:dd:d9:dd:c25:dd0:ec00:573a/1282c19:dd:d9:dd:c25:dd0:ec00:573a
602c19:dd:d9:dd:c25:dd0:ec00:573b/1282c19:dd:d9:dd:c25:dd0:ec00:573b
612c19:dd:d9:dd:c25:dd0:ec00:573c/1282c19:dd:d9:dd:c25:dd0:ec00:573c
622c19:dd:d9:dd:c25:dd0:ec00:573d/1282c19:dd:d9:dd:c25:dd0:ec00:573d
632c19:dd:d9:dd:c25:dd0:ec00:573e/1282c19:dd:d9:dd:c25:dd0:ec00:573e
642c19:dd:d9:dd:c25:dd0:ec00:573f/1282c19:dd:d9:dd:c25:dd0:ec00:573f
652c19:dd:d9:dd:c25:dd0:ec00:5740/1282c19:dd:d9:dd:c25:dd0:ec00:5740
662c19:dd:d9:dd:c25:dd0:ec00:5741/1282c19:dd:d9:dd:c25:dd0:ec00:5741
672c19:dd:d9:dd:c25:dd0:ec00:5742/1282c19:dd:d9:dd:c25:dd0:ec00:5742
682c19:dd:d9:dd:c25:dd0:ec00:5743/1282c19:dd:d9:dd:c25:dd0:ec00:5743
692c19:dd:d9:dd:c25:dd0:ec00:5744/1282c19:dd:d9:dd:c25:dd0:ec00:5744
702c19:dd:d9:dd:c25:dd0:ec00:5745/1282c19:dd:d9:dd:c25:dd0:ec00:5745
712c19:dd:d9:dd:c25:dd0:ec00:5746/1282c19:dd:d9:dd:c25:dd0:ec00:5746
722c19:dd:d9:dd:c25:dd0:ec00:5747/1282c19:dd:d9:dd:c25:dd0:ec00:5747
732c19:dd:d9:dd:c25:dd0:ec00:5748/1282c19:dd:d9:dd:c25:dd0:ec00:5748
742c19:dd:d9:dd:c25:dd0:ec00:5749/1282c19:dd:d9:dd:c25:dd0:ec00:5749
752c19:dd:d9:dd:c25:dd0:ec00:574a/1282c19:dd:d9:dd:c25:dd0:ec00:574a
762c19:dd:d9:dd:c25:dd0:ec00:574b/1282c19:dd:d9:dd:c25:dd0:ec00:574b
772c19:dd:d9:dd:c25:dd0:ec00:574c/1282c19:dd:d9:dd:c25:dd0:ec00:574c
782c19:dd:d9:dd:c25:dd0:ec00:574d/1282c19:dd:d9:dd:c25:dd0:ec00:574d
792c19:dd:d9:dd:c25:dd0:ec00:574e/1282c19:dd:d9:dd:c25:dd0:ec00:574e
802c19:dd:d9:dd:c25:dd0:ec00:574f/1282c19:dd:d9:dd:c25:dd0:ec00:574f
812c19:dd:d9:dd:c25:dd0:ec00:5750/1282c19:dd:d9:dd:c25:dd0:ec00:5750
822c19:dd:d9:dd:c25:dd0:ec00:5751/1282c19:dd:d9:dd:c25:dd0:ec00:5751
832c19:dd:d9:dd:c25:dd0:ec00:5752/1282c19:dd:d9:dd:c25:dd0:ec00:5752
842c19:dd:d9:dd:c25:dd0:ec00:5753/1282c19:dd:d9:dd:c25:dd0:ec00:5753
852c19:dd:d9:dd:c25:dd0:ec00:5754/1282c19:dd:d9:dd:c25:dd0:ec00:5754
862c19:dd:d9:dd:c25:dd0:ec00:5755/1282c19:dd:d9:dd:c25:dd0:ec00:5755
872c19:dd:d9:dd:c25:dd0:ec00:5756/1282c19:dd:d9:dd:c25:dd0:ec00:5756
882c19:dd:d9:dd:c25:dd0:ec00:5757/1282c19:dd:d9:dd:c25:dd0:ec00:5757
892c19:dd:d9:dd:c25:dd0:ec00:5758/1282c19:dd:d9:dd:c25:dd0:ec00:5758
902c19:dd:d9:dd:c25:dd0:ec00:5759/1282c19:dd:d9:dd:c25:dd0:ec00:5759
912c19:dd:d9:dd:c25:dd0:ec00:575a/1282c19:dd:d9:dd:c25:dd0:ec00:575a
922c19:dd:d9:dd:c25:dd0:ec00:575b/1282c19:dd:d9:dd:c25:dd0:ec00:575b
932c19:dd:d9:dd:c25:dd0:ec00:575c/1282c19:dd:d9:dd:c25:dd0:ec00:575c
942c19:dd:d9:dd:c25:dd0:ec00:575d/1282c19:dd:d9:dd:c25:dd0:ec00:575d
952c19:dd:d9:dd:c25:dd0:ec00:575e/1282c19:dd:d9:dd:c25:dd0:ec00:575e
962c19:dd:d9:dd:c25:dd0:ec00:575f/1282c19:dd:d9:dd:c25:dd0:ec00:575f
972c19:dd:d9:dd:c25:dd0:ec00:5760/1282c19:dd:d9:dd:c25:dd0:ec00:5760
982c19:dd:d9:dd:c25:dd0:ec00:5761/1282c19:dd:d9:dd:c25:dd0:ec00:5761
992c19:dd:d9:dd:c25:dd0:ec00:5762/1282c19:dd:d9:dd:c25:dd0:ec00:5762
1002c19:dd:d9:dd:c25:dd0:ec00:5763/1282c19:dd:d9:dd:c25:dd0:ec00:5763
1012c19:dd:d9:dd:c25:dd0:ec00:5764/1282c19:dd:d9:dd:c25:dd0:ec00:5764
1022c19:dd:d9:dd:c25:dd0:ec00:5765/1282c19:dd:d9:dd:c25:dd0:ec00:5765
1032c19:dd:d9:dd:c25:dd0:ec00:5766/1282c19:dd:d9:dd:c25:dd0:ec00:5766
1042c19:dd:d9:dd:c25:dd0:ec00:5767/1282c19:dd:d9:dd:c25:dd0:ec00:5767
1052c19:dd:d9:dd:c25:dd0:ec00:5768/1282c19:dd:d9:dd:c25:dd0:ec00:5768
1062c19:dd:d9:dd:c25:dd0:ec00:5769/1282c19:dd:d9:dd:c25:dd0:ec00:5769
1072c19:dd:d9:dd:c25:dd0:ec00:576a/1282c19:dd:d9:dd:c25:dd0:ec00:576a
1082c19:dd:d9:dd:c25:dd0:ec00:576b/1282c19:dd:d9:dd:c25:dd0:ec00:576b
1092c19:dd:d9:dd:c25:dd0:ec00:576c/1282c19:dd:d9:dd:c25:dd0:ec00:576c
1102c19:dd:d9:dd:c25:dd0:ec00:576d/1282c19:dd:d9:dd:c25:dd0:ec00:576d
1112c19:dd:d9:dd:c25:dd0:ec00:576e/1282c19:dd:d9:dd:c25:dd0:ec00:576e
1122c19:dd:d9:dd:c25:dd0:ec00:576f/1282c19:dd:d9:dd:c25:dd0:ec00:576f
1132c19:dd:d9:dd:c25:dd0:ec00:5770/1282c19:dd:d9:dd:c25:dd0:ec00:5770
1142c19:dd:d9:dd:c25:dd0:ec00:5771/1282c19:dd:d9:dd:c25:dd0:ec00:5771
1152c19:dd:d9:dd:c25:dd0:ec00:5772/1282c19:dd:d9:dd:c25:dd0:ec00:5772
1162c19:dd:d9:dd:c25:dd0:ec00:5773/1282c19:dd:d9:dd:c25:dd0:ec00:5773
1172c19:dd:d9:dd:c25:dd0:ec00:5774/1282c19:dd:d9:dd:c25:dd0:ec00:5774
1182c19:dd:d9:dd:c25:dd0:ec00:5775/1282c19:dd:d9:dd:c25:dd0:ec00:5775
1192c19:dd:d9:dd:c25:dd0:ec00:5776/1282c19:dd:d9:dd:c25:dd0:ec00:5776
1202c19:dd:d9:dd:c25:dd0:ec00:5777/1282c19:dd:d9:dd:c25:dd0:ec00:5777
1212c19:dd:d9:dd:c25:dd0:ec00:5778/1282c19:dd:d9:dd:c25:dd0:ec00:5778
1222c19:dd:d9:dd:c25:dd0:ec00:5779/1282c19:dd:d9:dd:c25:dd0:ec00:5779
1232c19:dd:d9:dd:c25:dd0:ec00:577a/1282c19:dd:d9:dd:c25:dd0:ec00:577a
1242c19:dd:d9:dd:c25:dd0:ec00:577b/1282c19:dd:d9:dd:c25:dd0:ec00:577b
1252c19:dd:d9:dd:c25:dd0:ec00:577c/1282c19:dd:d9:dd:c25:dd0:ec00:577c
1262c19:dd:d9:dd:c25:dd0:ec00:577d/1282c19:dd:d9:dd:c25:dd0:ec00:577d
1272c19:dd:d9:dd:c25:dd0:ec00:577e/1282c19:dd:d9:dd:c25:dd0:ec00:577e
1282c19:dd:d9:dd:c25:dd0:ec00:577f/1282c19:dd:d9:dd:c25:dd0:ec00:577f
1292c19:dd:d9:dd:c25:dd0:ec00:5780/1282c19:dd:d9:dd:c25:dd0:ec00:5780
1302c19:dd:d9:dd:c25:dd0:ec00:5781/1282c19:dd:d9:dd:c25:dd0:ec00:5781
1312c19:dd:d9:dd:c25:dd0:ec00:5782/1282c19:dd:d9:dd:c25:dd0:ec00:5782
1322c19:dd:d9:dd:c25:dd0:ec00:5783/1282c19:dd:d9:dd:c25:dd0:ec00:5783
1332c19:dd:d9:dd:c25:dd0:ec00:5784/1282c19:dd:d9:dd:c25:dd0:ec00:5784
1342c19:dd:d9:dd:c25:dd0:ec00:5785/1282c19:dd:d9:dd:c25:dd0:ec00:5785
1352c19:dd:d9:dd:c25:dd0:ec00:5786/1282c19:dd:d9:dd:c25:dd0:ec00:5786
1362c19:dd:d9:dd:c25:dd0:ec00:5787/1282c19:dd:d9:dd:c25:dd0:ec00:5787
1372c19:dd:d9:dd:c25:dd0:ec00:5788/1282c19:dd:d9:dd:c25:dd0:ec00:5788
1382c19:dd:d9:dd:c25:dd0:ec00:5789/1282c19:dd:d9:dd:c25:dd0:ec00:5789
1392c19:dd:d9:dd:c25:dd0:ec00:578a/1282c19:dd:d9:dd:c25:dd0:ec00:578a
1402c19:dd:d9:dd:c25:dd0:ec00:578b/1282c19:dd:d9:dd:c25:dd0:ec00:578b
1412c19:dd:d9:dd:c25:dd0:ec00:578c/1282c19:dd:d9:dd:c25:dd0:ec00:578c
1422c19:dd:d9:dd:c25:dd0:ec00:578d/1282c19:dd:d9:dd:c25:dd0:ec00:578d
1432c19:dd:d9:dd:c25:dd0:ec00:578e/1282c19:dd:d9:dd:c25:dd0:ec00:578e
1442c19:dd:d9:dd:c25:dd0:ec00:578f/1282c19:dd:d9:dd:c25:dd0:ec00:578f
1452c19:dd:d9:dd:c25:dd0:ec00:5790/1282c19:dd:d9:dd:c25:dd0:ec00:5790
1462c19:dd:d9:dd:c25:dd0:ec00:5791/1282c19:dd:d9:dd:c25:dd0:ec00:5791
1472c19:dd:d9:dd:c25:dd0:ec00:5792/1282c19:dd:d9:dd:c25:dd0:ec00:5792
1482c19:dd:d9:dd:c25:dd0:ec00:5793/1282c19:dd:d9:dd:c25:dd0:ec00:5793
1492c19:dd:d9:dd:c25:dd0:ec00:5794/1282c19:dd:d9:dd:c25:dd0:ec00:5794
1502c19:dd:d9:dd:c25:dd0:ec00:5795/1282c19:dd:d9:dd:c25:dd0:ec00:5795
1512c19:dd:d9:dd:c25:dd0:ec00:5796/1282c19:dd:d9:dd:c25:dd0:ec00:5796
1522c19:dd:d9:dd:c25:dd0:ec00:5797/1282c19:dd:d9:dd:c25:dd0:ec00:5797
1532c19:dd:d9:dd:c25:dd0:ec00:5798/1282c19:dd:d9:dd:c25:dd0:ec00:5798
1542c19:dd:d9:dd:c25:dd0:ec00:5799/1282c19:dd:d9:dd:c25:dd0:ec00:5799
1552c19:dd:d9:dd:c25:dd0:ec00:579a/1282c19:dd:d9:dd:c25:dd0:ec00:579a
1562c19:dd:d9:dd:c25:dd0:ec00:579b/1282c19:dd:d9:dd:c25:dd0:ec00:579b
1572c19:dd:d9:dd:c25:dd0:ec00:579c/1282c19:dd:d9:dd:c25:dd0:ec00:579c
1582c19:dd:d9:dd:c25:dd0:ec00:579d/1282c19:dd:d9:dd:c25:dd0:ec00:579d
1592c19:dd:d9:dd:c25:dd0:ec00:579e/1282c19:dd:d9:dd:c25:dd0:ec00:579e
1602c19:dd:d9:dd:c25:dd0:ec00:579f/1282c19:dd:d9:dd:c25:dd0:ec00:579f
1612c19:dd:d9:dd:c25:dd0:ec00:57a0/1282c19:dd:d9:dd:c25:dd0:ec00:57a0
1622c19:dd:d9:dd:c25:dd0:ec00:57a1/1282c19:dd:d9:dd:c25:dd0:ec00:57a1
1632c19:dd:d9:dd:c25:dd0:ec00:57a2/1282c19:dd:d9:dd:c25:dd0:ec00:57a2
1642c19:dd:d9:dd:c25:dd0:ec00:57a3/1282c19:dd:d9:dd:c25:dd0:ec00:57a3
1652c19:dd:d9:dd:c25:dd0:ec00:57a4/1282c19:dd:d9:dd:c25:dd0:ec00:57a4
1662c19:dd:d9:dd:c25:dd0:ec00:57a5/1282c19:dd:d9:dd:c25:dd0:ec00:57a5
1672c19:dd:d9:dd:c25:dd0:ec00:57a6/1282c19:dd:d9:dd:c25:dd0:ec00:57a6
1682c19:dd:d9:dd:c25:dd0:ec00:57a7/1282c19:dd:d9:dd:c25:dd0:ec00:57a7
1692c19:dd:d9:dd:c25:dd0:ec00:57a8/1282c19:dd:d9:dd:c25:dd0:ec00:57a8
1702c19:dd:d9:dd:c25:dd0:ec00:57a9/1282c19:dd:d9:dd:c25:dd0:ec00:57a9
1712c19:dd:d9:dd:c25:dd0:ec00:57aa/1282c19:dd:d9:dd:c25:dd0:ec00:57aa
1722c19:dd:d9:dd:c25:dd0:ec00:57ab/1282c19:dd:d9:dd:c25:dd0:ec00:57ab
1732c19:dd:d9:dd:c25:dd0:ec00:57ac/1282c19:dd:d9:dd:c25:dd0:ec00:57ac
1742c19:dd:d9:dd:c25:dd0:ec00:57ad/1282c19:dd:d9:dd:c25:dd0:ec00:57ad
1752c19:dd:d9:dd:c25:dd0:ec00:57ae/1282c19:dd:d9:dd:c25:dd0:ec00:57ae
1762c19:dd:d9:dd:c25:dd0:ec00:57af/1282c19:dd:d9:dd:c25:dd0:ec00:57af
1772c19:dd:d9:dd:c25:dd0:ec00:57b0/1282c19:dd:d9:dd:c25:dd0:ec00:57b0
1782c19:dd:d9:dd:c25:dd0:ec00:57b1/1282c19:dd:d9:dd:c25:dd0:ec00:57b1
1792c19:dd:d9:dd:c25:dd0:ec00:57b2/1282c19:dd:d9:dd:c25:dd0:ec00:57b2
1802c19:dd:d9:dd:c25:dd0:ec00:57b3/1282c19:dd:d9:dd:c25:dd0:ec00:57b3
1812c19:dd:d9:dd:c25:dd0:ec00:57b4/1282c19:dd:d9:dd:c25:dd0:ec00:57b4
1822c19:dd:d9:dd:c25:dd0:ec00:57b5/1282c19:dd:d9:dd:c25:dd0:ec00:57b5
1832c19:dd:d9:dd:c25:dd0:ec00:57b6/1282c19:dd:d9:dd:c25:dd0:ec00:57b6
1842c19:dd:d9:dd:c25:dd0:ec00:57b7/1282c19:dd:d9:dd:c25:dd0:ec00:57b7
1852c19:dd:d9:dd:c25:dd0:ec00:57b8/1282c19:dd:d9:dd:c25:dd0:ec00:57b8
1862c19:dd:d9:dd:c25:dd0:ec00:57b9/1282c19:dd:d9:dd:c25:dd0:ec00:57b9
1872c19:dd:d9:dd:c25:dd0:ec00:57ba/1282c19:dd:d9:dd:c25:dd0:ec00:57ba
1882c19:dd:d9:dd:c25:dd0:ec00:57bb/1282c19:dd:d9:dd:c25:dd0:ec00:57bb
1892c19:dd:d9:dd:c25:dd0:ec00:57bc/1282c19:dd:d9:dd:c25:dd0:ec00:57bc
1902c19:dd:d9:dd:c25:dd0:ec00:57bd/1282c19:dd:d9:dd:c25:dd0:ec00:57bd
1912c19:dd:d9:dd:c25:dd0:ec00:57be/1282c19:dd:d9:dd:c25:dd0:ec00:57be
1922c19:dd:d9:dd:c25:dd0:ec00:57bf/1282c19:dd:d9:dd:c25:dd0:ec00:57bf
1932c19:dd:d9:dd:c25:dd0:ec00:57c0/1282c19:dd:d9:dd:c25:dd0:ec00:57c0
1942c19:dd:d9:dd:c25:dd0:ec00:57c1/1282c19:dd:d9:dd:c25:dd0:ec00:57c1
1952c19:dd:d9:dd:c25:dd0:ec00:57c2/1282c19:dd:d9:dd:c25:dd0:ec00:57c2
1962c19:dd:d9:dd:c25:dd0:ec00:57c3/1282c19:dd:d9:dd:c25:dd0:ec00:57c3
1972c19:dd:d9:dd:c25:dd0:ec00:57c4/1282c19:dd:d9:dd:c25:dd0:ec00:57c4
1982c19:dd:d9:dd:c25:dd0:ec00:57c5/1282c19:dd:d9:dd:c25:dd0:ec00:57c5
1992c19:dd:d9:dd:c25:dd0:ec00:57c6/1282c19:dd:d9:dd:c25:dd0:ec00:57c6
2002c19:dd:d9:dd:c25:dd0:ec00:57c7/1282c19:dd:d9:dd:c25:dd0:ec00:57c7
2012c19:dd:d9:dd:c25:dd0:ec00:57c8/1282c19:dd:d9:dd:c25:dd0:ec00:57c8
2022c19:dd:d9:dd:c25:dd0:ec00:57c9/1282c19:dd:d9:dd:c25:dd0:ec00:57c9
2032c19:dd:d9:dd:c25:dd0:ec00:57ca/1282c19:dd:d9:dd:c25:dd0:ec00:57ca
2042c19:dd:d9:dd:c25:dd0:ec00:57cb/1282c19:dd:d9:dd:c25:dd0:ec00:57cb
2052c19:dd:d9:dd:c25:dd0:ec00:57cc/1282c19:dd:d9:dd:c25:dd0:ec00:57cc
2062c19:dd:d9:dd:c25:dd0:ec00:57cd/1282c19:dd:d9:dd:c25:dd0:ec00:57cd
2072c19:dd:d9:dd:c25:dd0:ec00:57ce/1282c19:dd:d9:dd:c25:dd0:ec00:57ce
2082c19:dd:d9:dd:c25:dd0:ec00:57cf/1282c19:dd:d9:dd:c25:dd0:ec00:57cf
2092c19:dd:d9:dd:c25:dd0:ec00:57d0/1282c19:dd:d9:dd:c25:dd0:ec00:57d0
2102c19:dd:d9:dd:c25:dd0:ec00:57d1/1282c19:dd:d9:dd:c25:dd0:ec00:57d1
2112c19:dd:d9:dd:c25:dd0:ec00:57d2/1282c19:dd:d9:dd:c25:dd0:ec00:57d2
2122c19:dd:d9:dd:c25:dd0:ec00:57d3/1282c19:dd:d9:dd:c25:dd0:ec00:57d3
2132c19:dd:d9:dd:c25:dd0:ec00:57d4/1282c19:dd:d9:dd:c25:dd0:ec00:57d4
2142c19:dd:d9:dd:c25:dd0:ec00:57d5/1282c19:dd:d9:dd:c25:dd0:ec00:57d5
2152c19:dd:d9:dd:c25:dd0:ec00:57d6/1282c19:dd:d9:dd:c25:dd0:ec00:57d6
2162c19:dd:d9:dd:c25:dd0:ec00:57d7/1282c19:dd:d9:dd:c25:dd0:ec00:57d7
2172c19:dd:d9:dd:c25:dd0:ec00:57d8/1282c19:dd:d9:dd:c25:dd0:ec00:57d8
2182c19:dd:d9:dd:c25:dd0:ec00:57d9/1282c19:dd:d9:dd:c25:dd0:ec00:57d9
2192c19:dd:d9:dd:c25:dd0:ec00:57da/1282c19:dd:d9:dd:c25:dd0:ec00:57da
2202c19:dd:d9:dd:c25:dd0:ec00:57db/1282c19:dd:d9:dd:c25:dd0:ec00:57db
2212c19:dd:d9:dd:c25:dd0:ec00:57dc/1282c19:dd:d9:dd:c25:dd0:ec00:57dc
2222c19:dd:d9:dd:c25:dd0:ec00:57dd/1282c19:dd:d9:dd:c25:dd0:ec00:57dd
2232c19:dd:d9:dd:c25:dd0:ec00:57de/1282c19:dd:d9:dd:c25:dd0:ec00:57de
2242c19:dd:d9:dd:c25:dd0:ec00:57df/1282c19:dd:d9:dd:c25:dd0:ec00:57df
2252c19:dd:d9:dd:c25:dd0:ec00:57e0/1282c19:dd:d9:dd:c25:dd0:ec00:57e0
2262c19:dd:d9:dd:c25:dd0:ec00:57e1/1282c19:dd:d9:dd:c25:dd0:ec00:57e1
2272c19:dd:d9:dd:c25:dd0:ec00:57e2/1282c19:dd:d9:dd:c25:dd0:ec00:57e2
2282c19:dd:d9:dd:c25:dd0:ec00:57e3/1282c19:dd:d9:dd:c25:dd0:ec00:57e3
2292c19:dd:d9:dd:c25:dd0:ec00:57e4/1282c19:dd:d9:dd:c25:dd0:ec00:57e4
2302c19:dd:d9:dd:c25:dd0:ec00:57e5/1282c19:dd:d9:dd:c25:dd0:ec00:57e5
2312c19:dd:d9:dd:c25:dd0:ec00:57e6/1282c19:dd:d9:dd:c25:dd0:ec00:57e6
2322c19:dd:d9:dd:c25:dd0:ec00:57e7/1282c19:dd:d9:dd:c25:dd0:ec00:57e7
2332c19:dd:d9:dd:c25:dd0:ec00:57e8/1282c19:dd:d9:dd:c25:dd0:ec00:57e8
2342c19:dd:d9:dd:c25:dd0:ec00:57e9/1282c19:dd:d9:dd:c25:dd0:ec00:57e9
2352c19:dd:d9:dd:c25:dd0:ec00:57ea/1282c19:dd:d9:dd:c25:dd0:ec00:57ea
2362c19:dd:d9:dd:c25:dd0:ec00:57eb/1282c19:dd:d9:dd:c25:dd0:ec00:57eb
2372c19:dd:d9:dd:c25:dd0:ec00:57ec/1282c19:dd:d9:dd:c25:dd0:ec00:57ec
2382c19:dd:d9:dd:c25:dd0:ec00:57ed/1282c19:dd:d9:dd:c25:dd0:ec00:57ed
2392c19:dd:d9:dd:c25:dd0:ec00:57ee/1282c19:dd:d9:dd:c25:dd0:ec00:57ee
2402c19:dd:d9:dd:c25:dd0:ec00:57ef/1282c19:dd:d9:dd:c25:dd0:ec00:57ef
2412c19:dd:d9:dd:c25:dd0:ec00:57f0/1282c19:dd:d9:dd:c25:dd0:ec00:57f0
2422c19:dd:d9:dd:c25:dd0:ec00:57f1/1282c19:dd:d9:dd:c25:dd0:ec00:57f1
2432c19:dd:d9:dd:c25:dd0:ec00:57f2/1282c19:dd:d9:dd:c25:dd0:ec00:57f2
2442c19:dd:d9:dd:c25:dd0:ec00:57f3/1282c19:dd:d9:dd:c25:dd0:ec00:57f3
2452c19:dd:d9:dd:c25:dd0:ec00:57f4/1282c19:dd:d9:dd:c25:dd0:ec00:57f4
2462c19:dd:d9:dd:c25:dd0:ec00:57f5/1282c19:dd:d9:dd:c25:dd0:ec00:57f5
2472c19:dd:d9:dd:c25:dd0:ec00:57f6/1282c19:dd:d9:dd:c25:dd0:ec00:57f6
2482c19:dd:d9:dd:c25:dd0:ec00:57f7/1282c19:dd:d9:dd:c25:dd0:ec00:57f7
2492c19:dd:d9:dd:c25:dd0:ec00:57f8/1282c19:dd:d9:dd:c25:dd0:ec00:57f8
2502c19:dd:d9:dd:c25:dd0:ec00:57f9/1282c19:dd:d9:dd:c25:dd0:ec00:57f9
2512c19:dd:d9:dd:c25:dd0:ec00:57fa/1282c19:dd:d9:dd:c25:dd0:ec00:57fa
2522c19:dd:d9:dd:c25:dd0:ec00:57fb/1282c19:dd:d9:dd:c25:dd0:ec00:57fb
2532c19:dd:d9:dd:c25:dd0:ec00:57fc/1282c19:dd:d9:dd:c25:dd0:ec00:57fc
2542c19:dd:d9:dd:c25:dd0:ec00:57fd/1282c19:dd:d9:dd:c25:dd0:ec00:57fd
2552c19:dd:d9:dd:c25:dd0:ec00:57fe/1282c19:dd:d9:dd:c25:dd0:ec00:57fe
2562c19:dd:d9:dd:c25:dd0:ec00:57ff/1282c19:dd:d9:dd:c25:dd0:ec00:57ff

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.