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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:6700/120
First address
2c19:dd:d9:dd:c25:c25:94de:6700
Last address
2c19:dd:d9:dd:c25:c25:94de:67ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:6700
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
7.6.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:6700/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:6700/1282c19:dd:d9:dd:c25:c25:94de:6700
22c19:dd:d9:dd:c25:c25:94de:6701/1282c19:dd:d9:dd:c25:c25:94de:6701
32c19:dd:d9:dd:c25:c25:94de:6702/1282c19:dd:d9:dd:c25:c25:94de:6702
42c19:dd:d9:dd:c25:c25:94de:6703/1282c19:dd:d9:dd:c25:c25:94de:6703
52c19:dd:d9:dd:c25:c25:94de:6704/1282c19:dd:d9:dd:c25:c25:94de:6704
62c19:dd:d9:dd:c25:c25:94de:6705/1282c19:dd:d9:dd:c25:c25:94de:6705
72c19:dd:d9:dd:c25:c25:94de:6706/1282c19:dd:d9:dd:c25:c25:94de:6706
82c19:dd:d9:dd:c25:c25:94de:6707/1282c19:dd:d9:dd:c25:c25:94de:6707
92c19:dd:d9:dd:c25:c25:94de:6708/1282c19:dd:d9:dd:c25:c25:94de:6708
102c19:dd:d9:dd:c25:c25:94de:6709/1282c19:dd:d9:dd:c25:c25:94de:6709
112c19:dd:d9:dd:c25:c25:94de:670a/1282c19:dd:d9:dd:c25:c25:94de:670a
122c19:dd:d9:dd:c25:c25:94de:670b/1282c19:dd:d9:dd:c25:c25:94de:670b
132c19:dd:d9:dd:c25:c25:94de:670c/1282c19:dd:d9:dd:c25:c25:94de:670c
142c19:dd:d9:dd:c25:c25:94de:670d/1282c19:dd:d9:dd:c25:c25:94de:670d
152c19:dd:d9:dd:c25:c25:94de:670e/1282c19:dd:d9:dd:c25:c25:94de:670e
162c19:dd:d9:dd:c25:c25:94de:670f/1282c19:dd:d9:dd:c25:c25:94de:670f
172c19:dd:d9:dd:c25:c25:94de:6710/1282c19:dd:d9:dd:c25:c25:94de:6710
182c19:dd:d9:dd:c25:c25:94de:6711/1282c19:dd:d9:dd:c25:c25:94de:6711
192c19:dd:d9:dd:c25:c25:94de:6712/1282c19:dd:d9:dd:c25:c25:94de:6712
202c19:dd:d9:dd:c25:c25:94de:6713/1282c19:dd:d9:dd:c25:c25:94de:6713
212c19:dd:d9:dd:c25:c25:94de:6714/1282c19:dd:d9:dd:c25:c25:94de:6714
222c19:dd:d9:dd:c25:c25:94de:6715/1282c19:dd:d9:dd:c25:c25:94de:6715
232c19:dd:d9:dd:c25:c25:94de:6716/1282c19:dd:d9:dd:c25:c25:94de:6716
242c19:dd:d9:dd:c25:c25:94de:6717/1282c19:dd:d9:dd:c25:c25:94de:6717
252c19:dd:d9:dd:c25:c25:94de:6718/1282c19:dd:d9:dd:c25:c25:94de:6718
262c19:dd:d9:dd:c25:c25:94de:6719/1282c19:dd:d9:dd:c25:c25:94de:6719
272c19:dd:d9:dd:c25:c25:94de:671a/1282c19:dd:d9:dd:c25:c25:94de:671a
282c19:dd:d9:dd:c25:c25:94de:671b/1282c19:dd:d9:dd:c25:c25:94de:671b
292c19:dd:d9:dd:c25:c25:94de:671c/1282c19:dd:d9:dd:c25:c25:94de:671c
302c19:dd:d9:dd:c25:c25:94de:671d/1282c19:dd:d9:dd:c25:c25:94de:671d
312c19:dd:d9:dd:c25:c25:94de:671e/1282c19:dd:d9:dd:c25:c25:94de:671e
322c19:dd:d9:dd:c25:c25:94de:671f/1282c19:dd:d9:dd:c25:c25:94de:671f
332c19:dd:d9:dd:c25:c25:94de:6720/1282c19:dd:d9:dd:c25:c25:94de:6720
342c19:dd:d9:dd:c25:c25:94de:6721/1282c19:dd:d9:dd:c25:c25:94de:6721
352c19:dd:d9:dd:c25:c25:94de:6722/1282c19:dd:d9:dd:c25:c25:94de:6722
362c19:dd:d9:dd:c25:c25:94de:6723/1282c19:dd:d9:dd:c25:c25:94de:6723
372c19:dd:d9:dd:c25:c25:94de:6724/1282c19:dd:d9:dd:c25:c25:94de:6724
382c19:dd:d9:dd:c25:c25:94de:6725/1282c19:dd:d9:dd:c25:c25:94de:6725
392c19:dd:d9:dd:c25:c25:94de:6726/1282c19:dd:d9:dd:c25:c25:94de:6726
402c19:dd:d9:dd:c25:c25:94de:6727/1282c19:dd:d9:dd:c25:c25:94de:6727
412c19:dd:d9:dd:c25:c25:94de:6728/1282c19:dd:d9:dd:c25:c25:94de:6728
422c19:dd:d9:dd:c25:c25:94de:6729/1282c19:dd:d9:dd:c25:c25:94de:6729
432c19:dd:d9:dd:c25:c25:94de:672a/1282c19:dd:d9:dd:c25:c25:94de:672a
442c19:dd:d9:dd:c25:c25:94de:672b/1282c19:dd:d9:dd:c25:c25:94de:672b
452c19:dd:d9:dd:c25:c25:94de:672c/1282c19:dd:d9:dd:c25:c25:94de:672c
462c19:dd:d9:dd:c25:c25:94de:672d/1282c19:dd:d9:dd:c25:c25:94de:672d
472c19:dd:d9:dd:c25:c25:94de:672e/1282c19:dd:d9:dd:c25:c25:94de:672e
482c19:dd:d9:dd:c25:c25:94de:672f/1282c19:dd:d9:dd:c25:c25:94de:672f
492c19:dd:d9:dd:c25:c25:94de:6730/1282c19:dd:d9:dd:c25:c25:94de:6730
502c19:dd:d9:dd:c25:c25:94de:6731/1282c19:dd:d9:dd:c25:c25:94de:6731
512c19:dd:d9:dd:c25:c25:94de:6732/1282c19:dd:d9:dd:c25:c25:94de:6732
522c19:dd:d9:dd:c25:c25:94de:6733/1282c19:dd:d9:dd:c25:c25:94de:6733
532c19:dd:d9:dd:c25:c25:94de:6734/1282c19:dd:d9:dd:c25:c25:94de:6734
542c19:dd:d9:dd:c25:c25:94de:6735/1282c19:dd:d9:dd:c25:c25:94de:6735
552c19:dd:d9:dd:c25:c25:94de:6736/1282c19:dd:d9:dd:c25:c25:94de:6736
562c19:dd:d9:dd:c25:c25:94de:6737/1282c19:dd:d9:dd:c25:c25:94de:6737
572c19:dd:d9:dd:c25:c25:94de:6738/1282c19:dd:d9:dd:c25:c25:94de:6738
582c19:dd:d9:dd:c25:c25:94de:6739/1282c19:dd:d9:dd:c25:c25:94de:6739
592c19:dd:d9:dd:c25:c25:94de:673a/1282c19:dd:d9:dd:c25:c25:94de:673a
602c19:dd:d9:dd:c25:c25:94de:673b/1282c19:dd:d9:dd:c25:c25:94de:673b
612c19:dd:d9:dd:c25:c25:94de:673c/1282c19:dd:d9:dd:c25:c25:94de:673c
622c19:dd:d9:dd:c25:c25:94de:673d/1282c19:dd:d9:dd:c25:c25:94de:673d
632c19:dd:d9:dd:c25:c25:94de:673e/1282c19:dd:d9:dd:c25:c25:94de:673e
642c19:dd:d9:dd:c25:c25:94de:673f/1282c19:dd:d9:dd:c25:c25:94de:673f
652c19:dd:d9:dd:c25:c25:94de:6740/1282c19:dd:d9:dd:c25:c25:94de:6740
662c19:dd:d9:dd:c25:c25:94de:6741/1282c19:dd:d9:dd:c25:c25:94de:6741
672c19:dd:d9:dd:c25:c25:94de:6742/1282c19:dd:d9:dd:c25:c25:94de:6742
682c19:dd:d9:dd:c25:c25:94de:6743/1282c19:dd:d9:dd:c25:c25:94de:6743
692c19:dd:d9:dd:c25:c25:94de:6744/1282c19:dd:d9:dd:c25:c25:94de:6744
702c19:dd:d9:dd:c25:c25:94de:6745/1282c19:dd:d9:dd:c25:c25:94de:6745
712c19:dd:d9:dd:c25:c25:94de:6746/1282c19:dd:d9:dd:c25:c25:94de:6746
722c19:dd:d9:dd:c25:c25:94de:6747/1282c19:dd:d9:dd:c25:c25:94de:6747
732c19:dd:d9:dd:c25:c25:94de:6748/1282c19:dd:d9:dd:c25:c25:94de:6748
742c19:dd:d9:dd:c25:c25:94de:6749/1282c19:dd:d9:dd:c25:c25:94de:6749
752c19:dd:d9:dd:c25:c25:94de:674a/1282c19:dd:d9:dd:c25:c25:94de:674a
762c19:dd:d9:dd:c25:c25:94de:674b/1282c19:dd:d9:dd:c25:c25:94de:674b
772c19:dd:d9:dd:c25:c25:94de:674c/1282c19:dd:d9:dd:c25:c25:94de:674c
782c19:dd:d9:dd:c25:c25:94de:674d/1282c19:dd:d9:dd:c25:c25:94de:674d
792c19:dd:d9:dd:c25:c25:94de:674e/1282c19:dd:d9:dd:c25:c25:94de:674e
802c19:dd:d9:dd:c25:c25:94de:674f/1282c19:dd:d9:dd:c25:c25:94de:674f
812c19:dd:d9:dd:c25:c25:94de:6750/1282c19:dd:d9:dd:c25:c25:94de:6750
822c19:dd:d9:dd:c25:c25:94de:6751/1282c19:dd:d9:dd:c25:c25:94de:6751
832c19:dd:d9:dd:c25:c25:94de:6752/1282c19:dd:d9:dd:c25:c25:94de:6752
842c19:dd:d9:dd:c25:c25:94de:6753/1282c19:dd:d9:dd:c25:c25:94de:6753
852c19:dd:d9:dd:c25:c25:94de:6754/1282c19:dd:d9:dd:c25:c25:94de:6754
862c19:dd:d9:dd:c25:c25:94de:6755/1282c19:dd:d9:dd:c25:c25:94de:6755
872c19:dd:d9:dd:c25:c25:94de:6756/1282c19:dd:d9:dd:c25:c25:94de:6756
882c19:dd:d9:dd:c25:c25:94de:6757/1282c19:dd:d9:dd:c25:c25:94de:6757
892c19:dd:d9:dd:c25:c25:94de:6758/1282c19:dd:d9:dd:c25:c25:94de:6758
902c19:dd:d9:dd:c25:c25:94de:6759/1282c19:dd:d9:dd:c25:c25:94de:6759
912c19:dd:d9:dd:c25:c25:94de:675a/1282c19:dd:d9:dd:c25:c25:94de:675a
922c19:dd:d9:dd:c25:c25:94de:675b/1282c19:dd:d9:dd:c25:c25:94de:675b
932c19:dd:d9:dd:c25:c25:94de:675c/1282c19:dd:d9:dd:c25:c25:94de:675c
942c19:dd:d9:dd:c25:c25:94de:675d/1282c19:dd:d9:dd:c25:c25:94de:675d
952c19:dd:d9:dd:c25:c25:94de:675e/1282c19:dd:d9:dd:c25:c25:94de:675e
962c19:dd:d9:dd:c25:c25:94de:675f/1282c19:dd:d9:dd:c25:c25:94de:675f
972c19:dd:d9:dd:c25:c25:94de:6760/1282c19:dd:d9:dd:c25:c25:94de:6760
982c19:dd:d9:dd:c25:c25:94de:6761/1282c19:dd:d9:dd:c25:c25:94de:6761
992c19:dd:d9:dd:c25:c25:94de:6762/1282c19:dd:d9:dd:c25:c25:94de:6762
1002c19:dd:d9:dd:c25:c25:94de:6763/1282c19:dd:d9:dd:c25:c25:94de:6763
1012c19:dd:d9:dd:c25:c25:94de:6764/1282c19:dd:d9:dd:c25:c25:94de:6764
1022c19:dd:d9:dd:c25:c25:94de:6765/1282c19:dd:d9:dd:c25:c25:94de:6765
1032c19:dd:d9:dd:c25:c25:94de:6766/1282c19:dd:d9:dd:c25:c25:94de:6766
1042c19:dd:d9:dd:c25:c25:94de:6767/1282c19:dd:d9:dd:c25:c25:94de:6767
1052c19:dd:d9:dd:c25:c25:94de:6768/1282c19:dd:d9:dd:c25:c25:94de:6768
1062c19:dd:d9:dd:c25:c25:94de:6769/1282c19:dd:d9:dd:c25:c25:94de:6769
1072c19:dd:d9:dd:c25:c25:94de:676a/1282c19:dd:d9:dd:c25:c25:94de:676a
1082c19:dd:d9:dd:c25:c25:94de:676b/1282c19:dd:d9:dd:c25:c25:94de:676b
1092c19:dd:d9:dd:c25:c25:94de:676c/1282c19:dd:d9:dd:c25:c25:94de:676c
1102c19:dd:d9:dd:c25:c25:94de:676d/1282c19:dd:d9:dd:c25:c25:94de:676d
1112c19:dd:d9:dd:c25:c25:94de:676e/1282c19:dd:d9:dd:c25:c25:94de:676e
1122c19:dd:d9:dd:c25:c25:94de:676f/1282c19:dd:d9:dd:c25:c25:94de:676f
1132c19:dd:d9:dd:c25:c25:94de:6770/1282c19:dd:d9:dd:c25:c25:94de:6770
1142c19:dd:d9:dd:c25:c25:94de:6771/1282c19:dd:d9:dd:c25:c25:94de:6771
1152c19:dd:d9:dd:c25:c25:94de:6772/1282c19:dd:d9:dd:c25:c25:94de:6772
1162c19:dd:d9:dd:c25:c25:94de:6773/1282c19:dd:d9:dd:c25:c25:94de:6773
1172c19:dd:d9:dd:c25:c25:94de:6774/1282c19:dd:d9:dd:c25:c25:94de:6774
1182c19:dd:d9:dd:c25:c25:94de:6775/1282c19:dd:d9:dd:c25:c25:94de:6775
1192c19:dd:d9:dd:c25:c25:94de:6776/1282c19:dd:d9:dd:c25:c25:94de:6776
1202c19:dd:d9:dd:c25:c25:94de:6777/1282c19:dd:d9:dd:c25:c25:94de:6777
1212c19:dd:d9:dd:c25:c25:94de:6778/1282c19:dd:d9:dd:c25:c25:94de:6778
1222c19:dd:d9:dd:c25:c25:94de:6779/1282c19:dd:d9:dd:c25:c25:94de:6779
1232c19:dd:d9:dd:c25:c25:94de:677a/1282c19:dd:d9:dd:c25:c25:94de:677a
1242c19:dd:d9:dd:c25:c25:94de:677b/1282c19:dd:d9:dd:c25:c25:94de:677b
1252c19:dd:d9:dd:c25:c25:94de:677c/1282c19:dd:d9:dd:c25:c25:94de:677c
1262c19:dd:d9:dd:c25:c25:94de:677d/1282c19:dd:d9:dd:c25:c25:94de:677d
1272c19:dd:d9:dd:c25:c25:94de:677e/1282c19:dd:d9:dd:c25:c25:94de:677e
1282c19:dd:d9:dd:c25:c25:94de:677f/1282c19:dd:d9:dd:c25:c25:94de:677f
1292c19:dd:d9:dd:c25:c25:94de:6780/1282c19:dd:d9:dd:c25:c25:94de:6780
1302c19:dd:d9:dd:c25:c25:94de:6781/1282c19:dd:d9:dd:c25:c25:94de:6781
1312c19:dd:d9:dd:c25:c25:94de:6782/1282c19:dd:d9:dd:c25:c25:94de:6782
1322c19:dd:d9:dd:c25:c25:94de:6783/1282c19:dd:d9:dd:c25:c25:94de:6783
1332c19:dd:d9:dd:c25:c25:94de:6784/1282c19:dd:d9:dd:c25:c25:94de:6784
1342c19:dd:d9:dd:c25:c25:94de:6785/1282c19:dd:d9:dd:c25:c25:94de:6785
1352c19:dd:d9:dd:c25:c25:94de:6786/1282c19:dd:d9:dd:c25:c25:94de:6786
1362c19:dd:d9:dd:c25:c25:94de:6787/1282c19:dd:d9:dd:c25:c25:94de:6787
1372c19:dd:d9:dd:c25:c25:94de:6788/1282c19:dd:d9:dd:c25:c25:94de:6788
1382c19:dd:d9:dd:c25:c25:94de:6789/1282c19:dd:d9:dd:c25:c25:94de:6789
1392c19:dd:d9:dd:c25:c25:94de:678a/1282c19:dd:d9:dd:c25:c25:94de:678a
1402c19:dd:d9:dd:c25:c25:94de:678b/1282c19:dd:d9:dd:c25:c25:94de:678b
1412c19:dd:d9:dd:c25:c25:94de:678c/1282c19:dd:d9:dd:c25:c25:94de:678c
1422c19:dd:d9:dd:c25:c25:94de:678d/1282c19:dd:d9:dd:c25:c25:94de:678d
1432c19:dd:d9:dd:c25:c25:94de:678e/1282c19:dd:d9:dd:c25:c25:94de:678e
1442c19:dd:d9:dd:c25:c25:94de:678f/1282c19:dd:d9:dd:c25:c25:94de:678f
1452c19:dd:d9:dd:c25:c25:94de:6790/1282c19:dd:d9:dd:c25:c25:94de:6790
1462c19:dd:d9:dd:c25:c25:94de:6791/1282c19:dd:d9:dd:c25:c25:94de:6791
1472c19:dd:d9:dd:c25:c25:94de:6792/1282c19:dd:d9:dd:c25:c25:94de:6792
1482c19:dd:d9:dd:c25:c25:94de:6793/1282c19:dd:d9:dd:c25:c25:94de:6793
1492c19:dd:d9:dd:c25:c25:94de:6794/1282c19:dd:d9:dd:c25:c25:94de:6794
1502c19:dd:d9:dd:c25:c25:94de:6795/1282c19:dd:d9:dd:c25:c25:94de:6795
1512c19:dd:d9:dd:c25:c25:94de:6796/1282c19:dd:d9:dd:c25:c25:94de:6796
1522c19:dd:d9:dd:c25:c25:94de:6797/1282c19:dd:d9:dd:c25:c25:94de:6797
1532c19:dd:d9:dd:c25:c25:94de:6798/1282c19:dd:d9:dd:c25:c25:94de:6798
1542c19:dd:d9:dd:c25:c25:94de:6799/1282c19:dd:d9:dd:c25:c25:94de:6799
1552c19:dd:d9:dd:c25:c25:94de:679a/1282c19:dd:d9:dd:c25:c25:94de:679a
1562c19:dd:d9:dd:c25:c25:94de:679b/1282c19:dd:d9:dd:c25:c25:94de:679b
1572c19:dd:d9:dd:c25:c25:94de:679c/1282c19:dd:d9:dd:c25:c25:94de:679c
1582c19:dd:d9:dd:c25:c25:94de:679d/1282c19:dd:d9:dd:c25:c25:94de:679d
1592c19:dd:d9:dd:c25:c25:94de:679e/1282c19:dd:d9:dd:c25:c25:94de:679e
1602c19:dd:d9:dd:c25:c25:94de:679f/1282c19:dd:d9:dd:c25:c25:94de:679f
1612c19:dd:d9:dd:c25:c25:94de:67a0/1282c19:dd:d9:dd:c25:c25:94de:67a0
1622c19:dd:d9:dd:c25:c25:94de:67a1/1282c19:dd:d9:dd:c25:c25:94de:67a1
1632c19:dd:d9:dd:c25:c25:94de:67a2/1282c19:dd:d9:dd:c25:c25:94de:67a2
1642c19:dd:d9:dd:c25:c25:94de:67a3/1282c19:dd:d9:dd:c25:c25:94de:67a3
1652c19:dd:d9:dd:c25:c25:94de:67a4/1282c19:dd:d9:dd:c25:c25:94de:67a4
1662c19:dd:d9:dd:c25:c25:94de:67a5/1282c19:dd:d9:dd:c25:c25:94de:67a5
1672c19:dd:d9:dd:c25:c25:94de:67a6/1282c19:dd:d9:dd:c25:c25:94de:67a6
1682c19:dd:d9:dd:c25:c25:94de:67a7/1282c19:dd:d9:dd:c25:c25:94de:67a7
1692c19:dd:d9:dd:c25:c25:94de:67a8/1282c19:dd:d9:dd:c25:c25:94de:67a8
1702c19:dd:d9:dd:c25:c25:94de:67a9/1282c19:dd:d9:dd:c25:c25:94de:67a9
1712c19:dd:d9:dd:c25:c25:94de:67aa/1282c19:dd:d9:dd:c25:c25:94de:67aa
1722c19:dd:d9:dd:c25:c25:94de:67ab/1282c19:dd:d9:dd:c25:c25:94de:67ab
1732c19:dd:d9:dd:c25:c25:94de:67ac/1282c19:dd:d9:dd:c25:c25:94de:67ac
1742c19:dd:d9:dd:c25:c25:94de:67ad/1282c19:dd:d9:dd:c25:c25:94de:67ad
1752c19:dd:d9:dd:c25:c25:94de:67ae/1282c19:dd:d9:dd:c25:c25:94de:67ae
1762c19:dd:d9:dd:c25:c25:94de:67af/1282c19:dd:d9:dd:c25:c25:94de:67af
1772c19:dd:d9:dd:c25:c25:94de:67b0/1282c19:dd:d9:dd:c25:c25:94de:67b0
1782c19:dd:d9:dd:c25:c25:94de:67b1/1282c19:dd:d9:dd:c25:c25:94de:67b1
1792c19:dd:d9:dd:c25:c25:94de:67b2/1282c19:dd:d9:dd:c25:c25:94de:67b2
1802c19:dd:d9:dd:c25:c25:94de:67b3/1282c19:dd:d9:dd:c25:c25:94de:67b3
1812c19:dd:d9:dd:c25:c25:94de:67b4/1282c19:dd:d9:dd:c25:c25:94de:67b4
1822c19:dd:d9:dd:c25:c25:94de:67b5/1282c19:dd:d9:dd:c25:c25:94de:67b5
1832c19:dd:d9:dd:c25:c25:94de:67b6/1282c19:dd:d9:dd:c25:c25:94de:67b6
1842c19:dd:d9:dd:c25:c25:94de:67b7/1282c19:dd:d9:dd:c25:c25:94de:67b7
1852c19:dd:d9:dd:c25:c25:94de:67b8/1282c19:dd:d9:dd:c25:c25:94de:67b8
1862c19:dd:d9:dd:c25:c25:94de:67b9/1282c19:dd:d9:dd:c25:c25:94de:67b9
1872c19:dd:d9:dd:c25:c25:94de:67ba/1282c19:dd:d9:dd:c25:c25:94de:67ba
1882c19:dd:d9:dd:c25:c25:94de:67bb/1282c19:dd:d9:dd:c25:c25:94de:67bb
1892c19:dd:d9:dd:c25:c25:94de:67bc/1282c19:dd:d9:dd:c25:c25:94de:67bc
1902c19:dd:d9:dd:c25:c25:94de:67bd/1282c19:dd:d9:dd:c25:c25:94de:67bd
1912c19:dd:d9:dd:c25:c25:94de:67be/1282c19:dd:d9:dd:c25:c25:94de:67be
1922c19:dd:d9:dd:c25:c25:94de:67bf/1282c19:dd:d9:dd:c25:c25:94de:67bf
1932c19:dd:d9:dd:c25:c25:94de:67c0/1282c19:dd:d9:dd:c25:c25:94de:67c0
1942c19:dd:d9:dd:c25:c25:94de:67c1/1282c19:dd:d9:dd:c25:c25:94de:67c1
1952c19:dd:d9:dd:c25:c25:94de:67c2/1282c19:dd:d9:dd:c25:c25:94de:67c2
1962c19:dd:d9:dd:c25:c25:94de:67c3/1282c19:dd:d9:dd:c25:c25:94de:67c3
1972c19:dd:d9:dd:c25:c25:94de:67c4/1282c19:dd:d9:dd:c25:c25:94de:67c4
1982c19:dd:d9:dd:c25:c25:94de:67c5/1282c19:dd:d9:dd:c25:c25:94de:67c5
1992c19:dd:d9:dd:c25:c25:94de:67c6/1282c19:dd:d9:dd:c25:c25:94de:67c6
2002c19:dd:d9:dd:c25:c25:94de:67c7/1282c19:dd:d9:dd:c25:c25:94de:67c7
2012c19:dd:d9:dd:c25:c25:94de:67c8/1282c19:dd:d9:dd:c25:c25:94de:67c8
2022c19:dd:d9:dd:c25:c25:94de:67c9/1282c19:dd:d9:dd:c25:c25:94de:67c9
2032c19:dd:d9:dd:c25:c25:94de:67ca/1282c19:dd:d9:dd:c25:c25:94de:67ca
2042c19:dd:d9:dd:c25:c25:94de:67cb/1282c19:dd:d9:dd:c25:c25:94de:67cb
2052c19:dd:d9:dd:c25:c25:94de:67cc/1282c19:dd:d9:dd:c25:c25:94de:67cc
2062c19:dd:d9:dd:c25:c25:94de:67cd/1282c19:dd:d9:dd:c25:c25:94de:67cd
2072c19:dd:d9:dd:c25:c25:94de:67ce/1282c19:dd:d9:dd:c25:c25:94de:67ce
2082c19:dd:d9:dd:c25:c25:94de:67cf/1282c19:dd:d9:dd:c25:c25:94de:67cf
2092c19:dd:d9:dd:c25:c25:94de:67d0/1282c19:dd:d9:dd:c25:c25:94de:67d0
2102c19:dd:d9:dd:c25:c25:94de:67d1/1282c19:dd:d9:dd:c25:c25:94de:67d1
2112c19:dd:d9:dd:c25:c25:94de:67d2/1282c19:dd:d9:dd:c25:c25:94de:67d2
2122c19:dd:d9:dd:c25:c25:94de:67d3/1282c19:dd:d9:dd:c25:c25:94de:67d3
2132c19:dd:d9:dd:c25:c25:94de:67d4/1282c19:dd:d9:dd:c25:c25:94de:67d4
2142c19:dd:d9:dd:c25:c25:94de:67d5/1282c19:dd:d9:dd:c25:c25:94de:67d5
2152c19:dd:d9:dd:c25:c25:94de:67d6/1282c19:dd:d9:dd:c25:c25:94de:67d6
2162c19:dd:d9:dd:c25:c25:94de:67d7/1282c19:dd:d9:dd:c25:c25:94de:67d7
2172c19:dd:d9:dd:c25:c25:94de:67d8/1282c19:dd:d9:dd:c25:c25:94de:67d8
2182c19:dd:d9:dd:c25:c25:94de:67d9/1282c19:dd:d9:dd:c25:c25:94de:67d9
2192c19:dd:d9:dd:c25:c25:94de:67da/1282c19:dd:d9:dd:c25:c25:94de:67da
2202c19:dd:d9:dd:c25:c25:94de:67db/1282c19:dd:d9:dd:c25:c25:94de:67db
2212c19:dd:d9:dd:c25:c25:94de:67dc/1282c19:dd:d9:dd:c25:c25:94de:67dc
2222c19:dd:d9:dd:c25:c25:94de:67dd/1282c19:dd:d9:dd:c25:c25:94de:67dd
2232c19:dd:d9:dd:c25:c25:94de:67de/1282c19:dd:d9:dd:c25:c25:94de:67de
2242c19:dd:d9:dd:c25:c25:94de:67df/1282c19:dd:d9:dd:c25:c25:94de:67df
2252c19:dd:d9:dd:c25:c25:94de:67e0/1282c19:dd:d9:dd:c25:c25:94de:67e0
2262c19:dd:d9:dd:c25:c25:94de:67e1/1282c19:dd:d9:dd:c25:c25:94de:67e1
2272c19:dd:d9:dd:c25:c25:94de:67e2/1282c19:dd:d9:dd:c25:c25:94de:67e2
2282c19:dd:d9:dd:c25:c25:94de:67e3/1282c19:dd:d9:dd:c25:c25:94de:67e3
2292c19:dd:d9:dd:c25:c25:94de:67e4/1282c19:dd:d9:dd:c25:c25:94de:67e4
2302c19:dd:d9:dd:c25:c25:94de:67e5/1282c19:dd:d9:dd:c25:c25:94de:67e5
2312c19:dd:d9:dd:c25:c25:94de:67e6/1282c19:dd:d9:dd:c25:c25:94de:67e6
2322c19:dd:d9:dd:c25:c25:94de:67e7/1282c19:dd:d9:dd:c25:c25:94de:67e7
2332c19:dd:d9:dd:c25:c25:94de:67e8/1282c19:dd:d9:dd:c25:c25:94de:67e8
2342c19:dd:d9:dd:c25:c25:94de:67e9/1282c19:dd:d9:dd:c25:c25:94de:67e9
2352c19:dd:d9:dd:c25:c25:94de:67ea/1282c19:dd:d9:dd:c25:c25:94de:67ea
2362c19:dd:d9:dd:c25:c25:94de:67eb/1282c19:dd:d9:dd:c25:c25:94de:67eb
2372c19:dd:d9:dd:c25:c25:94de:67ec/1282c19:dd:d9:dd:c25:c25:94de:67ec
2382c19:dd:d9:dd:c25:c25:94de:67ed/1282c19:dd:d9:dd:c25:c25:94de:67ed
2392c19:dd:d9:dd:c25:c25:94de:67ee/1282c19:dd:d9:dd:c25:c25:94de:67ee
2402c19:dd:d9:dd:c25:c25:94de:67ef/1282c19:dd:d9:dd:c25:c25:94de:67ef
2412c19:dd:d9:dd:c25:c25:94de:67f0/1282c19:dd:d9:dd:c25:c25:94de:67f0
2422c19:dd:d9:dd:c25:c25:94de:67f1/1282c19:dd:d9:dd:c25:c25:94de:67f1
2432c19:dd:d9:dd:c25:c25:94de:67f2/1282c19:dd:d9:dd:c25:c25:94de:67f2
2442c19:dd:d9:dd:c25:c25:94de:67f3/1282c19:dd:d9:dd:c25:c25:94de:67f3
2452c19:dd:d9:dd:c25:c25:94de:67f4/1282c19:dd:d9:dd:c25:c25:94de:67f4
2462c19:dd:d9:dd:c25:c25:94de:67f5/1282c19:dd:d9:dd:c25:c25:94de:67f5
2472c19:dd:d9:dd:c25:c25:94de:67f6/1282c19:dd:d9:dd:c25:c25:94de:67f6
2482c19:dd:d9:dd:c25:c25:94de:67f7/1282c19:dd:d9:dd:c25:c25:94de:67f7
2492c19:dd:d9:dd:c25:c25:94de:67f8/1282c19:dd:d9:dd:c25:c25:94de:67f8
2502c19:dd:d9:dd:c25:c25:94de:67f9/1282c19:dd:d9:dd:c25:c25:94de:67f9
2512c19:dd:d9:dd:c25:c25:94de:67fa/1282c19:dd:d9:dd:c25:c25:94de:67fa
2522c19:dd:d9:dd:c25:c25:94de:67fb/1282c19:dd:d9:dd:c25:c25:94de:67fb
2532c19:dd:d9:dd:c25:c25:94de:67fc/1282c19:dd:d9:dd:c25:c25:94de:67fc
2542c19:dd:d9:dd:c25:c25:94de:67fd/1282c19:dd:d9:dd:c25:c25:94de:67fd
2552c19:dd:d9:dd:c25:c25:94de:67fe/1282c19:dd:d9:dd:c25:c25:94de:67fe
2562c19:dd:d9:dd:c25:c25:94de:67ff/1282c19:dd:d9:dd:c25:c25:94de:67ff

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.