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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:8700/120
First address
2c19:dd:d9:dd:c25:c25:94de:8700
Last address
2c19:dd:d9:dd:c25:c25:94de:87ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:8700
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
7.8.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:8700/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:8700/1282c19:dd:d9:dd:c25:c25:94de:8700
22c19:dd:d9:dd:c25:c25:94de:8701/1282c19:dd:d9:dd:c25:c25:94de:8701
32c19:dd:d9:dd:c25:c25:94de:8702/1282c19:dd:d9:dd:c25:c25:94de:8702
42c19:dd:d9:dd:c25:c25:94de:8703/1282c19:dd:d9:dd:c25:c25:94de:8703
52c19:dd:d9:dd:c25:c25:94de:8704/1282c19:dd:d9:dd:c25:c25:94de:8704
62c19:dd:d9:dd:c25:c25:94de:8705/1282c19:dd:d9:dd:c25:c25:94de:8705
72c19:dd:d9:dd:c25:c25:94de:8706/1282c19:dd:d9:dd:c25:c25:94de:8706
82c19:dd:d9:dd:c25:c25:94de:8707/1282c19:dd:d9:dd:c25:c25:94de:8707
92c19:dd:d9:dd:c25:c25:94de:8708/1282c19:dd:d9:dd:c25:c25:94de:8708
102c19:dd:d9:dd:c25:c25:94de:8709/1282c19:dd:d9:dd:c25:c25:94de:8709
112c19:dd:d9:dd:c25:c25:94de:870a/1282c19:dd:d9:dd:c25:c25:94de:870a
122c19:dd:d9:dd:c25:c25:94de:870b/1282c19:dd:d9:dd:c25:c25:94de:870b
132c19:dd:d9:dd:c25:c25:94de:870c/1282c19:dd:d9:dd:c25:c25:94de:870c
142c19:dd:d9:dd:c25:c25:94de:870d/1282c19:dd:d9:dd:c25:c25:94de:870d
152c19:dd:d9:dd:c25:c25:94de:870e/1282c19:dd:d9:dd:c25:c25:94de:870e
162c19:dd:d9:dd:c25:c25:94de:870f/1282c19:dd:d9:dd:c25:c25:94de:870f
172c19:dd:d9:dd:c25:c25:94de:8710/1282c19:dd:d9:dd:c25:c25:94de:8710
182c19:dd:d9:dd:c25:c25:94de:8711/1282c19:dd:d9:dd:c25:c25:94de:8711
192c19:dd:d9:dd:c25:c25:94de:8712/1282c19:dd:d9:dd:c25:c25:94de:8712
202c19:dd:d9:dd:c25:c25:94de:8713/1282c19:dd:d9:dd:c25:c25:94de:8713
212c19:dd:d9:dd:c25:c25:94de:8714/1282c19:dd:d9:dd:c25:c25:94de:8714
222c19:dd:d9:dd:c25:c25:94de:8715/1282c19:dd:d9:dd:c25:c25:94de:8715
232c19:dd:d9:dd:c25:c25:94de:8716/1282c19:dd:d9:dd:c25:c25:94de:8716
242c19:dd:d9:dd:c25:c25:94de:8717/1282c19:dd:d9:dd:c25:c25:94de:8717
252c19:dd:d9:dd:c25:c25:94de:8718/1282c19:dd:d9:dd:c25:c25:94de:8718
262c19:dd:d9:dd:c25:c25:94de:8719/1282c19:dd:d9:dd:c25:c25:94de:8719
272c19:dd:d9:dd:c25:c25:94de:871a/1282c19:dd:d9:dd:c25:c25:94de:871a
282c19:dd:d9:dd:c25:c25:94de:871b/1282c19:dd:d9:dd:c25:c25:94de:871b
292c19:dd:d9:dd:c25:c25:94de:871c/1282c19:dd:d9:dd:c25:c25:94de:871c
302c19:dd:d9:dd:c25:c25:94de:871d/1282c19:dd:d9:dd:c25:c25:94de:871d
312c19:dd:d9:dd:c25:c25:94de:871e/1282c19:dd:d9:dd:c25:c25:94de:871e
322c19:dd:d9:dd:c25:c25:94de:871f/1282c19:dd:d9:dd:c25:c25:94de:871f
332c19:dd:d9:dd:c25:c25:94de:8720/1282c19:dd:d9:dd:c25:c25:94de:8720
342c19:dd:d9:dd:c25:c25:94de:8721/1282c19:dd:d9:dd:c25:c25:94de:8721
352c19:dd:d9:dd:c25:c25:94de:8722/1282c19:dd:d9:dd:c25:c25:94de:8722
362c19:dd:d9:dd:c25:c25:94de:8723/1282c19:dd:d9:dd:c25:c25:94de:8723
372c19:dd:d9:dd:c25:c25:94de:8724/1282c19:dd:d9:dd:c25:c25:94de:8724
382c19:dd:d9:dd:c25:c25:94de:8725/1282c19:dd:d9:dd:c25:c25:94de:8725
392c19:dd:d9:dd:c25:c25:94de:8726/1282c19:dd:d9:dd:c25:c25:94de:8726
402c19:dd:d9:dd:c25:c25:94de:8727/1282c19:dd:d9:dd:c25:c25:94de:8727
412c19:dd:d9:dd:c25:c25:94de:8728/1282c19:dd:d9:dd:c25:c25:94de:8728
422c19:dd:d9:dd:c25:c25:94de:8729/1282c19:dd:d9:dd:c25:c25:94de:8729
432c19:dd:d9:dd:c25:c25:94de:872a/1282c19:dd:d9:dd:c25:c25:94de:872a
442c19:dd:d9:dd:c25:c25:94de:872b/1282c19:dd:d9:dd:c25:c25:94de:872b
452c19:dd:d9:dd:c25:c25:94de:872c/1282c19:dd:d9:dd:c25:c25:94de:872c
462c19:dd:d9:dd:c25:c25:94de:872d/1282c19:dd:d9:dd:c25:c25:94de:872d
472c19:dd:d9:dd:c25:c25:94de:872e/1282c19:dd:d9:dd:c25:c25:94de:872e
482c19:dd:d9:dd:c25:c25:94de:872f/1282c19:dd:d9:dd:c25:c25:94de:872f
492c19:dd:d9:dd:c25:c25:94de:8730/1282c19:dd:d9:dd:c25:c25:94de:8730
502c19:dd:d9:dd:c25:c25:94de:8731/1282c19:dd:d9:dd:c25:c25:94de:8731
512c19:dd:d9:dd:c25:c25:94de:8732/1282c19:dd:d9:dd:c25:c25:94de:8732
522c19:dd:d9:dd:c25:c25:94de:8733/1282c19:dd:d9:dd:c25:c25:94de:8733
532c19:dd:d9:dd:c25:c25:94de:8734/1282c19:dd:d9:dd:c25:c25:94de:8734
542c19:dd:d9:dd:c25:c25:94de:8735/1282c19:dd:d9:dd:c25:c25:94de:8735
552c19:dd:d9:dd:c25:c25:94de:8736/1282c19:dd:d9:dd:c25:c25:94de:8736
562c19:dd:d9:dd:c25:c25:94de:8737/1282c19:dd:d9:dd:c25:c25:94de:8737
572c19:dd:d9:dd:c25:c25:94de:8738/1282c19:dd:d9:dd:c25:c25:94de:8738
582c19:dd:d9:dd:c25:c25:94de:8739/1282c19:dd:d9:dd:c25:c25:94de:8739
592c19:dd:d9:dd:c25:c25:94de:873a/1282c19:dd:d9:dd:c25:c25:94de:873a
602c19:dd:d9:dd:c25:c25:94de:873b/1282c19:dd:d9:dd:c25:c25:94de:873b
612c19:dd:d9:dd:c25:c25:94de:873c/1282c19:dd:d9:dd:c25:c25:94de:873c
622c19:dd:d9:dd:c25:c25:94de:873d/1282c19:dd:d9:dd:c25:c25:94de:873d
632c19:dd:d9:dd:c25:c25:94de:873e/1282c19:dd:d9:dd:c25:c25:94de:873e
642c19:dd:d9:dd:c25:c25:94de:873f/1282c19:dd:d9:dd:c25:c25:94de:873f
652c19:dd:d9:dd:c25:c25:94de:8740/1282c19:dd:d9:dd:c25:c25:94de:8740
662c19:dd:d9:dd:c25:c25:94de:8741/1282c19:dd:d9:dd:c25:c25:94de:8741
672c19:dd:d9:dd:c25:c25:94de:8742/1282c19:dd:d9:dd:c25:c25:94de:8742
682c19:dd:d9:dd:c25:c25:94de:8743/1282c19:dd:d9:dd:c25:c25:94de:8743
692c19:dd:d9:dd:c25:c25:94de:8744/1282c19:dd:d9:dd:c25:c25:94de:8744
702c19:dd:d9:dd:c25:c25:94de:8745/1282c19:dd:d9:dd:c25:c25:94de:8745
712c19:dd:d9:dd:c25:c25:94de:8746/1282c19:dd:d9:dd:c25:c25:94de:8746
722c19:dd:d9:dd:c25:c25:94de:8747/1282c19:dd:d9:dd:c25:c25:94de:8747
732c19:dd:d9:dd:c25:c25:94de:8748/1282c19:dd:d9:dd:c25:c25:94de:8748
742c19:dd:d9:dd:c25:c25:94de:8749/1282c19:dd:d9:dd:c25:c25:94de:8749
752c19:dd:d9:dd:c25:c25:94de:874a/1282c19:dd:d9:dd:c25:c25:94de:874a
762c19:dd:d9:dd:c25:c25:94de:874b/1282c19:dd:d9:dd:c25:c25:94de:874b
772c19:dd:d9:dd:c25:c25:94de:874c/1282c19:dd:d9:dd:c25:c25:94de:874c
782c19:dd:d9:dd:c25:c25:94de:874d/1282c19:dd:d9:dd:c25:c25:94de:874d
792c19:dd:d9:dd:c25:c25:94de:874e/1282c19:dd:d9:dd:c25:c25:94de:874e
802c19:dd:d9:dd:c25:c25:94de:874f/1282c19:dd:d9:dd:c25:c25:94de:874f
812c19:dd:d9:dd:c25:c25:94de:8750/1282c19:dd:d9:dd:c25:c25:94de:8750
822c19:dd:d9:dd:c25:c25:94de:8751/1282c19:dd:d9:dd:c25:c25:94de:8751
832c19:dd:d9:dd:c25:c25:94de:8752/1282c19:dd:d9:dd:c25:c25:94de:8752
842c19:dd:d9:dd:c25:c25:94de:8753/1282c19:dd:d9:dd:c25:c25:94de:8753
852c19:dd:d9:dd:c25:c25:94de:8754/1282c19:dd:d9:dd:c25:c25:94de:8754
862c19:dd:d9:dd:c25:c25:94de:8755/1282c19:dd:d9:dd:c25:c25:94de:8755
872c19:dd:d9:dd:c25:c25:94de:8756/1282c19:dd:d9:dd:c25:c25:94de:8756
882c19:dd:d9:dd:c25:c25:94de:8757/1282c19:dd:d9:dd:c25:c25:94de:8757
892c19:dd:d9:dd:c25:c25:94de:8758/1282c19:dd:d9:dd:c25:c25:94de:8758
902c19:dd:d9:dd:c25:c25:94de:8759/1282c19:dd:d9:dd:c25:c25:94de:8759
912c19:dd:d9:dd:c25:c25:94de:875a/1282c19:dd:d9:dd:c25:c25:94de:875a
922c19:dd:d9:dd:c25:c25:94de:875b/1282c19:dd:d9:dd:c25:c25:94de:875b
932c19:dd:d9:dd:c25:c25:94de:875c/1282c19:dd:d9:dd:c25:c25:94de:875c
942c19:dd:d9:dd:c25:c25:94de:875d/1282c19:dd:d9:dd:c25:c25:94de:875d
952c19:dd:d9:dd:c25:c25:94de:875e/1282c19:dd:d9:dd:c25:c25:94de:875e
962c19:dd:d9:dd:c25:c25:94de:875f/1282c19:dd:d9:dd:c25:c25:94de:875f
972c19:dd:d9:dd:c25:c25:94de:8760/1282c19:dd:d9:dd:c25:c25:94de:8760
982c19:dd:d9:dd:c25:c25:94de:8761/1282c19:dd:d9:dd:c25:c25:94de:8761
992c19:dd:d9:dd:c25:c25:94de:8762/1282c19:dd:d9:dd:c25:c25:94de:8762
1002c19:dd:d9:dd:c25:c25:94de:8763/1282c19:dd:d9:dd:c25:c25:94de:8763
1012c19:dd:d9:dd:c25:c25:94de:8764/1282c19:dd:d9:dd:c25:c25:94de:8764
1022c19:dd:d9:dd:c25:c25:94de:8765/1282c19:dd:d9:dd:c25:c25:94de:8765
1032c19:dd:d9:dd:c25:c25:94de:8766/1282c19:dd:d9:dd:c25:c25:94de:8766
1042c19:dd:d9:dd:c25:c25:94de:8767/1282c19:dd:d9:dd:c25:c25:94de:8767
1052c19:dd:d9:dd:c25:c25:94de:8768/1282c19:dd:d9:dd:c25:c25:94de:8768
1062c19:dd:d9:dd:c25:c25:94de:8769/1282c19:dd:d9:dd:c25:c25:94de:8769
1072c19:dd:d9:dd:c25:c25:94de:876a/1282c19:dd:d9:dd:c25:c25:94de:876a
1082c19:dd:d9:dd:c25:c25:94de:876b/1282c19:dd:d9:dd:c25:c25:94de:876b
1092c19:dd:d9:dd:c25:c25:94de:876c/1282c19:dd:d9:dd:c25:c25:94de:876c
1102c19:dd:d9:dd:c25:c25:94de:876d/1282c19:dd:d9:dd:c25:c25:94de:876d
1112c19:dd:d9:dd:c25:c25:94de:876e/1282c19:dd:d9:dd:c25:c25:94de:876e
1122c19:dd:d9:dd:c25:c25:94de:876f/1282c19:dd:d9:dd:c25:c25:94de:876f
1132c19:dd:d9:dd:c25:c25:94de:8770/1282c19:dd:d9:dd:c25:c25:94de:8770
1142c19:dd:d9:dd:c25:c25:94de:8771/1282c19:dd:d9:dd:c25:c25:94de:8771
1152c19:dd:d9:dd:c25:c25:94de:8772/1282c19:dd:d9:dd:c25:c25:94de:8772
1162c19:dd:d9:dd:c25:c25:94de:8773/1282c19:dd:d9:dd:c25:c25:94de:8773
1172c19:dd:d9:dd:c25:c25:94de:8774/1282c19:dd:d9:dd:c25:c25:94de:8774
1182c19:dd:d9:dd:c25:c25:94de:8775/1282c19:dd:d9:dd:c25:c25:94de:8775
1192c19:dd:d9:dd:c25:c25:94de:8776/1282c19:dd:d9:dd:c25:c25:94de:8776
1202c19:dd:d9:dd:c25:c25:94de:8777/1282c19:dd:d9:dd:c25:c25:94de:8777
1212c19:dd:d9:dd:c25:c25:94de:8778/1282c19:dd:d9:dd:c25:c25:94de:8778
1222c19:dd:d9:dd:c25:c25:94de:8779/1282c19:dd:d9:dd:c25:c25:94de:8779
1232c19:dd:d9:dd:c25:c25:94de:877a/1282c19:dd:d9:dd:c25:c25:94de:877a
1242c19:dd:d9:dd:c25:c25:94de:877b/1282c19:dd:d9:dd:c25:c25:94de:877b
1252c19:dd:d9:dd:c25:c25:94de:877c/1282c19:dd:d9:dd:c25:c25:94de:877c
1262c19:dd:d9:dd:c25:c25:94de:877d/1282c19:dd:d9:dd:c25:c25:94de:877d
1272c19:dd:d9:dd:c25:c25:94de:877e/1282c19:dd:d9:dd:c25:c25:94de:877e
1282c19:dd:d9:dd:c25:c25:94de:877f/1282c19:dd:d9:dd:c25:c25:94de:877f
1292c19:dd:d9:dd:c25:c25:94de:8780/1282c19:dd:d9:dd:c25:c25:94de:8780
1302c19:dd:d9:dd:c25:c25:94de:8781/1282c19:dd:d9:dd:c25:c25:94de:8781
1312c19:dd:d9:dd:c25:c25:94de:8782/1282c19:dd:d9:dd:c25:c25:94de:8782
1322c19:dd:d9:dd:c25:c25:94de:8783/1282c19:dd:d9:dd:c25:c25:94de:8783
1332c19:dd:d9:dd:c25:c25:94de:8784/1282c19:dd:d9:dd:c25:c25:94de:8784
1342c19:dd:d9:dd:c25:c25:94de:8785/1282c19:dd:d9:dd:c25:c25:94de:8785
1352c19:dd:d9:dd:c25:c25:94de:8786/1282c19:dd:d9:dd:c25:c25:94de:8786
1362c19:dd:d9:dd:c25:c25:94de:8787/1282c19:dd:d9:dd:c25:c25:94de:8787
1372c19:dd:d9:dd:c25:c25:94de:8788/1282c19:dd:d9:dd:c25:c25:94de:8788
1382c19:dd:d9:dd:c25:c25:94de:8789/1282c19:dd:d9:dd:c25:c25:94de:8789
1392c19:dd:d9:dd:c25:c25:94de:878a/1282c19:dd:d9:dd:c25:c25:94de:878a
1402c19:dd:d9:dd:c25:c25:94de:878b/1282c19:dd:d9:dd:c25:c25:94de:878b
1412c19:dd:d9:dd:c25:c25:94de:878c/1282c19:dd:d9:dd:c25:c25:94de:878c
1422c19:dd:d9:dd:c25:c25:94de:878d/1282c19:dd:d9:dd:c25:c25:94de:878d
1432c19:dd:d9:dd:c25:c25:94de:878e/1282c19:dd:d9:dd:c25:c25:94de:878e
1442c19:dd:d9:dd:c25:c25:94de:878f/1282c19:dd:d9:dd:c25:c25:94de:878f
1452c19:dd:d9:dd:c25:c25:94de:8790/1282c19:dd:d9:dd:c25:c25:94de:8790
1462c19:dd:d9:dd:c25:c25:94de:8791/1282c19:dd:d9:dd:c25:c25:94de:8791
1472c19:dd:d9:dd:c25:c25:94de:8792/1282c19:dd:d9:dd:c25:c25:94de:8792
1482c19:dd:d9:dd:c25:c25:94de:8793/1282c19:dd:d9:dd:c25:c25:94de:8793
1492c19:dd:d9:dd:c25:c25:94de:8794/1282c19:dd:d9:dd:c25:c25:94de:8794
1502c19:dd:d9:dd:c25:c25:94de:8795/1282c19:dd:d9:dd:c25:c25:94de:8795
1512c19:dd:d9:dd:c25:c25:94de:8796/1282c19:dd:d9:dd:c25:c25:94de:8796
1522c19:dd:d9:dd:c25:c25:94de:8797/1282c19:dd:d9:dd:c25:c25:94de:8797
1532c19:dd:d9:dd:c25:c25:94de:8798/1282c19:dd:d9:dd:c25:c25:94de:8798
1542c19:dd:d9:dd:c25:c25:94de:8799/1282c19:dd:d9:dd:c25:c25:94de:8799
1552c19:dd:d9:dd:c25:c25:94de:879a/1282c19:dd:d9:dd:c25:c25:94de:879a
1562c19:dd:d9:dd:c25:c25:94de:879b/1282c19:dd:d9:dd:c25:c25:94de:879b
1572c19:dd:d9:dd:c25:c25:94de:879c/1282c19:dd:d9:dd:c25:c25:94de:879c
1582c19:dd:d9:dd:c25:c25:94de:879d/1282c19:dd:d9:dd:c25:c25:94de:879d
1592c19:dd:d9:dd:c25:c25:94de:879e/1282c19:dd:d9:dd:c25:c25:94de:879e
1602c19:dd:d9:dd:c25:c25:94de:879f/1282c19:dd:d9:dd:c25:c25:94de:879f
1612c19:dd:d9:dd:c25:c25:94de:87a0/1282c19:dd:d9:dd:c25:c25:94de:87a0
1622c19:dd:d9:dd:c25:c25:94de:87a1/1282c19:dd:d9:dd:c25:c25:94de:87a1
1632c19:dd:d9:dd:c25:c25:94de:87a2/1282c19:dd:d9:dd:c25:c25:94de:87a2
1642c19:dd:d9:dd:c25:c25:94de:87a3/1282c19:dd:d9:dd:c25:c25:94de:87a3
1652c19:dd:d9:dd:c25:c25:94de:87a4/1282c19:dd:d9:dd:c25:c25:94de:87a4
1662c19:dd:d9:dd:c25:c25:94de:87a5/1282c19:dd:d9:dd:c25:c25:94de:87a5
1672c19:dd:d9:dd:c25:c25:94de:87a6/1282c19:dd:d9:dd:c25:c25:94de:87a6
1682c19:dd:d9:dd:c25:c25:94de:87a7/1282c19:dd:d9:dd:c25:c25:94de:87a7
1692c19:dd:d9:dd:c25:c25:94de:87a8/1282c19:dd:d9:dd:c25:c25:94de:87a8
1702c19:dd:d9:dd:c25:c25:94de:87a9/1282c19:dd:d9:dd:c25:c25:94de:87a9
1712c19:dd:d9:dd:c25:c25:94de:87aa/1282c19:dd:d9:dd:c25:c25:94de:87aa
1722c19:dd:d9:dd:c25:c25:94de:87ab/1282c19:dd:d9:dd:c25:c25:94de:87ab
1732c19:dd:d9:dd:c25:c25:94de:87ac/1282c19:dd:d9:dd:c25:c25:94de:87ac
1742c19:dd:d9:dd:c25:c25:94de:87ad/1282c19:dd:d9:dd:c25:c25:94de:87ad
1752c19:dd:d9:dd:c25:c25:94de:87ae/1282c19:dd:d9:dd:c25:c25:94de:87ae
1762c19:dd:d9:dd:c25:c25:94de:87af/1282c19:dd:d9:dd:c25:c25:94de:87af
1772c19:dd:d9:dd:c25:c25:94de:87b0/1282c19:dd:d9:dd:c25:c25:94de:87b0
1782c19:dd:d9:dd:c25:c25:94de:87b1/1282c19:dd:d9:dd:c25:c25:94de:87b1
1792c19:dd:d9:dd:c25:c25:94de:87b2/1282c19:dd:d9:dd:c25:c25:94de:87b2
1802c19:dd:d9:dd:c25:c25:94de:87b3/1282c19:dd:d9:dd:c25:c25:94de:87b3
1812c19:dd:d9:dd:c25:c25:94de:87b4/1282c19:dd:d9:dd:c25:c25:94de:87b4
1822c19:dd:d9:dd:c25:c25:94de:87b5/1282c19:dd:d9:dd:c25:c25:94de:87b5
1832c19:dd:d9:dd:c25:c25:94de:87b6/1282c19:dd:d9:dd:c25:c25:94de:87b6
1842c19:dd:d9:dd:c25:c25:94de:87b7/1282c19:dd:d9:dd:c25:c25:94de:87b7
1852c19:dd:d9:dd:c25:c25:94de:87b8/1282c19:dd:d9:dd:c25:c25:94de:87b8
1862c19:dd:d9:dd:c25:c25:94de:87b9/1282c19:dd:d9:dd:c25:c25:94de:87b9
1872c19:dd:d9:dd:c25:c25:94de:87ba/1282c19:dd:d9:dd:c25:c25:94de:87ba
1882c19:dd:d9:dd:c25:c25:94de:87bb/1282c19:dd:d9:dd:c25:c25:94de:87bb
1892c19:dd:d9:dd:c25:c25:94de:87bc/1282c19:dd:d9:dd:c25:c25:94de:87bc
1902c19:dd:d9:dd:c25:c25:94de:87bd/1282c19:dd:d9:dd:c25:c25:94de:87bd
1912c19:dd:d9:dd:c25:c25:94de:87be/1282c19:dd:d9:dd:c25:c25:94de:87be
1922c19:dd:d9:dd:c25:c25:94de:87bf/1282c19:dd:d9:dd:c25:c25:94de:87bf
1932c19:dd:d9:dd:c25:c25:94de:87c0/1282c19:dd:d9:dd:c25:c25:94de:87c0
1942c19:dd:d9:dd:c25:c25:94de:87c1/1282c19:dd:d9:dd:c25:c25:94de:87c1
1952c19:dd:d9:dd:c25:c25:94de:87c2/1282c19:dd:d9:dd:c25:c25:94de:87c2
1962c19:dd:d9:dd:c25:c25:94de:87c3/1282c19:dd:d9:dd:c25:c25:94de:87c3
1972c19:dd:d9:dd:c25:c25:94de:87c4/1282c19:dd:d9:dd:c25:c25:94de:87c4
1982c19:dd:d9:dd:c25:c25:94de:87c5/1282c19:dd:d9:dd:c25:c25:94de:87c5
1992c19:dd:d9:dd:c25:c25:94de:87c6/1282c19:dd:d9:dd:c25:c25:94de:87c6
2002c19:dd:d9:dd:c25:c25:94de:87c7/1282c19:dd:d9:dd:c25:c25:94de:87c7
2012c19:dd:d9:dd:c25:c25:94de:87c8/1282c19:dd:d9:dd:c25:c25:94de:87c8
2022c19:dd:d9:dd:c25:c25:94de:87c9/1282c19:dd:d9:dd:c25:c25:94de:87c9
2032c19:dd:d9:dd:c25:c25:94de:87ca/1282c19:dd:d9:dd:c25:c25:94de:87ca
2042c19:dd:d9:dd:c25:c25:94de:87cb/1282c19:dd:d9:dd:c25:c25:94de:87cb
2052c19:dd:d9:dd:c25:c25:94de:87cc/1282c19:dd:d9:dd:c25:c25:94de:87cc
2062c19:dd:d9:dd:c25:c25:94de:87cd/1282c19:dd:d9:dd:c25:c25:94de:87cd
2072c19:dd:d9:dd:c25:c25:94de:87ce/1282c19:dd:d9:dd:c25:c25:94de:87ce
2082c19:dd:d9:dd:c25:c25:94de:87cf/1282c19:dd:d9:dd:c25:c25:94de:87cf
2092c19:dd:d9:dd:c25:c25:94de:87d0/1282c19:dd:d9:dd:c25:c25:94de:87d0
2102c19:dd:d9:dd:c25:c25:94de:87d1/1282c19:dd:d9:dd:c25:c25:94de:87d1
2112c19:dd:d9:dd:c25:c25:94de:87d2/1282c19:dd:d9:dd:c25:c25:94de:87d2
2122c19:dd:d9:dd:c25:c25:94de:87d3/1282c19:dd:d9:dd:c25:c25:94de:87d3
2132c19:dd:d9:dd:c25:c25:94de:87d4/1282c19:dd:d9:dd:c25:c25:94de:87d4
2142c19:dd:d9:dd:c25:c25:94de:87d5/1282c19:dd:d9:dd:c25:c25:94de:87d5
2152c19:dd:d9:dd:c25:c25:94de:87d6/1282c19:dd:d9:dd:c25:c25:94de:87d6
2162c19:dd:d9:dd:c25:c25:94de:87d7/1282c19:dd:d9:dd:c25:c25:94de:87d7
2172c19:dd:d9:dd:c25:c25:94de:87d8/1282c19:dd:d9:dd:c25:c25:94de:87d8
2182c19:dd:d9:dd:c25:c25:94de:87d9/1282c19:dd:d9:dd:c25:c25:94de:87d9
2192c19:dd:d9:dd:c25:c25:94de:87da/1282c19:dd:d9:dd:c25:c25:94de:87da
2202c19:dd:d9:dd:c25:c25:94de:87db/1282c19:dd:d9:dd:c25:c25:94de:87db
2212c19:dd:d9:dd:c25:c25:94de:87dc/1282c19:dd:d9:dd:c25:c25:94de:87dc
2222c19:dd:d9:dd:c25:c25:94de:87dd/1282c19:dd:d9:dd:c25:c25:94de:87dd
2232c19:dd:d9:dd:c25:c25:94de:87de/1282c19:dd:d9:dd:c25:c25:94de:87de
2242c19:dd:d9:dd:c25:c25:94de:87df/1282c19:dd:d9:dd:c25:c25:94de:87df
2252c19:dd:d9:dd:c25:c25:94de:87e0/1282c19:dd:d9:dd:c25:c25:94de:87e0
2262c19:dd:d9:dd:c25:c25:94de:87e1/1282c19:dd:d9:dd:c25:c25:94de:87e1
2272c19:dd:d9:dd:c25:c25:94de:87e2/1282c19:dd:d9:dd:c25:c25:94de:87e2
2282c19:dd:d9:dd:c25:c25:94de:87e3/1282c19:dd:d9:dd:c25:c25:94de:87e3
2292c19:dd:d9:dd:c25:c25:94de:87e4/1282c19:dd:d9:dd:c25:c25:94de:87e4
2302c19:dd:d9:dd:c25:c25:94de:87e5/1282c19:dd:d9:dd:c25:c25:94de:87e5
2312c19:dd:d9:dd:c25:c25:94de:87e6/1282c19:dd:d9:dd:c25:c25:94de:87e6
2322c19:dd:d9:dd:c25:c25:94de:87e7/1282c19:dd:d9:dd:c25:c25:94de:87e7
2332c19:dd:d9:dd:c25:c25:94de:87e8/1282c19:dd:d9:dd:c25:c25:94de:87e8
2342c19:dd:d9:dd:c25:c25:94de:87e9/1282c19:dd:d9:dd:c25:c25:94de:87e9
2352c19:dd:d9:dd:c25:c25:94de:87ea/1282c19:dd:d9:dd:c25:c25:94de:87ea
2362c19:dd:d9:dd:c25:c25:94de:87eb/1282c19:dd:d9:dd:c25:c25:94de:87eb
2372c19:dd:d9:dd:c25:c25:94de:87ec/1282c19:dd:d9:dd:c25:c25:94de:87ec
2382c19:dd:d9:dd:c25:c25:94de:87ed/1282c19:dd:d9:dd:c25:c25:94de:87ed
2392c19:dd:d9:dd:c25:c25:94de:87ee/1282c19:dd:d9:dd:c25:c25:94de:87ee
2402c19:dd:d9:dd:c25:c25:94de:87ef/1282c19:dd:d9:dd:c25:c25:94de:87ef
2412c19:dd:d9:dd:c25:c25:94de:87f0/1282c19:dd:d9:dd:c25:c25:94de:87f0
2422c19:dd:d9:dd:c25:c25:94de:87f1/1282c19:dd:d9:dd:c25:c25:94de:87f1
2432c19:dd:d9:dd:c25:c25:94de:87f2/1282c19:dd:d9:dd:c25:c25:94de:87f2
2442c19:dd:d9:dd:c25:c25:94de:87f3/1282c19:dd:d9:dd:c25:c25:94de:87f3
2452c19:dd:d9:dd:c25:c25:94de:87f4/1282c19:dd:d9:dd:c25:c25:94de:87f4
2462c19:dd:d9:dd:c25:c25:94de:87f5/1282c19:dd:d9:dd:c25:c25:94de:87f5
2472c19:dd:d9:dd:c25:c25:94de:87f6/1282c19:dd:d9:dd:c25:c25:94de:87f6
2482c19:dd:d9:dd:c25:c25:94de:87f7/1282c19:dd:d9:dd:c25:c25:94de:87f7
2492c19:dd:d9:dd:c25:c25:94de:87f8/1282c19:dd:d9:dd:c25:c25:94de:87f8
2502c19:dd:d9:dd:c25:c25:94de:87f9/1282c19:dd:d9:dd:c25:c25:94de:87f9
2512c19:dd:d9:dd:c25:c25:94de:87fa/1282c19:dd:d9:dd:c25:c25:94de:87fa
2522c19:dd:d9:dd:c25:c25:94de:87fb/1282c19:dd:d9:dd:c25:c25:94de:87fb
2532c19:dd:d9:dd:c25:c25:94de:87fc/1282c19:dd:d9:dd:c25:c25:94de:87fc
2542c19:dd:d9:dd:c25:c25:94de:87fd/1282c19:dd:d9:dd:c25:c25:94de:87fd
2552c19:dd:d9:dd:c25:c25:94de:87fe/1282c19:dd:d9:dd:c25:c25:94de:87fe
2562c19:dd:d9:dd:c25:c25:94de:87ff/1282c19:dd:d9:dd:c25:c25:94de:87ff

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.