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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:8800/120
First address
2c19:dd:d9:dd:c25:c25:94de:8800
Last address
2c19:dd:d9:dd:c25:c25:94de:88ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:8800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.8.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:8800/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:8800/1282c19:dd:d9:dd:c25:c25:94de:8800
22c19:dd:d9:dd:c25:c25:94de:8801/1282c19:dd:d9:dd:c25:c25:94de:8801
32c19:dd:d9:dd:c25:c25:94de:8802/1282c19:dd:d9:dd:c25:c25:94de:8802
42c19:dd:d9:dd:c25:c25:94de:8803/1282c19:dd:d9:dd:c25:c25:94de:8803
52c19:dd:d9:dd:c25:c25:94de:8804/1282c19:dd:d9:dd:c25:c25:94de:8804
62c19:dd:d9:dd:c25:c25:94de:8805/1282c19:dd:d9:dd:c25:c25:94de:8805
72c19:dd:d9:dd:c25:c25:94de:8806/1282c19:dd:d9:dd:c25:c25:94de:8806
82c19:dd:d9:dd:c25:c25:94de:8807/1282c19:dd:d9:dd:c25:c25:94de:8807
92c19:dd:d9:dd:c25:c25:94de:8808/1282c19:dd:d9:dd:c25:c25:94de:8808
102c19:dd:d9:dd:c25:c25:94de:8809/1282c19:dd:d9:dd:c25:c25:94de:8809
112c19:dd:d9:dd:c25:c25:94de:880a/1282c19:dd:d9:dd:c25:c25:94de:880a
122c19:dd:d9:dd:c25:c25:94de:880b/1282c19:dd:d9:dd:c25:c25:94de:880b
132c19:dd:d9:dd:c25:c25:94de:880c/1282c19:dd:d9:dd:c25:c25:94de:880c
142c19:dd:d9:dd:c25:c25:94de:880d/1282c19:dd:d9:dd:c25:c25:94de:880d
152c19:dd:d9:dd:c25:c25:94de:880e/1282c19:dd:d9:dd:c25:c25:94de:880e
162c19:dd:d9:dd:c25:c25:94de:880f/1282c19:dd:d9:dd:c25:c25:94de:880f
172c19:dd:d9:dd:c25:c25:94de:8810/1282c19:dd:d9:dd:c25:c25:94de:8810
182c19:dd:d9:dd:c25:c25:94de:8811/1282c19:dd:d9:dd:c25:c25:94de:8811
192c19:dd:d9:dd:c25:c25:94de:8812/1282c19:dd:d9:dd:c25:c25:94de:8812
202c19:dd:d9:dd:c25:c25:94de:8813/1282c19:dd:d9:dd:c25:c25:94de:8813
212c19:dd:d9:dd:c25:c25:94de:8814/1282c19:dd:d9:dd:c25:c25:94de:8814
222c19:dd:d9:dd:c25:c25:94de:8815/1282c19:dd:d9:dd:c25:c25:94de:8815
232c19:dd:d9:dd:c25:c25:94de:8816/1282c19:dd:d9:dd:c25:c25:94de:8816
242c19:dd:d9:dd:c25:c25:94de:8817/1282c19:dd:d9:dd:c25:c25:94de:8817
252c19:dd:d9:dd:c25:c25:94de:8818/1282c19:dd:d9:dd:c25:c25:94de:8818
262c19:dd:d9:dd:c25:c25:94de:8819/1282c19:dd:d9:dd:c25:c25:94de:8819
272c19:dd:d9:dd:c25:c25:94de:881a/1282c19:dd:d9:dd:c25:c25:94de:881a
282c19:dd:d9:dd:c25:c25:94de:881b/1282c19:dd:d9:dd:c25:c25:94de:881b
292c19:dd:d9:dd:c25:c25:94de:881c/1282c19:dd:d9:dd:c25:c25:94de:881c
302c19:dd:d9:dd:c25:c25:94de:881d/1282c19:dd:d9:dd:c25:c25:94de:881d
312c19:dd:d9:dd:c25:c25:94de:881e/1282c19:dd:d9:dd:c25:c25:94de:881e
322c19:dd:d9:dd:c25:c25:94de:881f/1282c19:dd:d9:dd:c25:c25:94de:881f
332c19:dd:d9:dd:c25:c25:94de:8820/1282c19:dd:d9:dd:c25:c25:94de:8820
342c19:dd:d9:dd:c25:c25:94de:8821/1282c19:dd:d9:dd:c25:c25:94de:8821
352c19:dd:d9:dd:c25:c25:94de:8822/1282c19:dd:d9:dd:c25:c25:94de:8822
362c19:dd:d9:dd:c25:c25:94de:8823/1282c19:dd:d9:dd:c25:c25:94de:8823
372c19:dd:d9:dd:c25:c25:94de:8824/1282c19:dd:d9:dd:c25:c25:94de:8824
382c19:dd:d9:dd:c25:c25:94de:8825/1282c19:dd:d9:dd:c25:c25:94de:8825
392c19:dd:d9:dd:c25:c25:94de:8826/1282c19:dd:d9:dd:c25:c25:94de:8826
402c19:dd:d9:dd:c25:c25:94de:8827/1282c19:dd:d9:dd:c25:c25:94de:8827
412c19:dd:d9:dd:c25:c25:94de:8828/1282c19:dd:d9:dd:c25:c25:94de:8828
422c19:dd:d9:dd:c25:c25:94de:8829/1282c19:dd:d9:dd:c25:c25:94de:8829
432c19:dd:d9:dd:c25:c25:94de:882a/1282c19:dd:d9:dd:c25:c25:94de:882a
442c19:dd:d9:dd:c25:c25:94de:882b/1282c19:dd:d9:dd:c25:c25:94de:882b
452c19:dd:d9:dd:c25:c25:94de:882c/1282c19:dd:d9:dd:c25:c25:94de:882c
462c19:dd:d9:dd:c25:c25:94de:882d/1282c19:dd:d9:dd:c25:c25:94de:882d
472c19:dd:d9:dd:c25:c25:94de:882e/1282c19:dd:d9:dd:c25:c25:94de:882e
482c19:dd:d9:dd:c25:c25:94de:882f/1282c19:dd:d9:dd:c25:c25:94de:882f
492c19:dd:d9:dd:c25:c25:94de:8830/1282c19:dd:d9:dd:c25:c25:94de:8830
502c19:dd:d9:dd:c25:c25:94de:8831/1282c19:dd:d9:dd:c25:c25:94de:8831
512c19:dd:d9:dd:c25:c25:94de:8832/1282c19:dd:d9:dd:c25:c25:94de:8832
522c19:dd:d9:dd:c25:c25:94de:8833/1282c19:dd:d9:dd:c25:c25:94de:8833
532c19:dd:d9:dd:c25:c25:94de:8834/1282c19:dd:d9:dd:c25:c25:94de:8834
542c19:dd:d9:dd:c25:c25:94de:8835/1282c19:dd:d9:dd:c25:c25:94de:8835
552c19:dd:d9:dd:c25:c25:94de:8836/1282c19:dd:d9:dd:c25:c25:94de:8836
562c19:dd:d9:dd:c25:c25:94de:8837/1282c19:dd:d9:dd:c25:c25:94de:8837
572c19:dd:d9:dd:c25:c25:94de:8838/1282c19:dd:d9:dd:c25:c25:94de:8838
582c19:dd:d9:dd:c25:c25:94de:8839/1282c19:dd:d9:dd:c25:c25:94de:8839
592c19:dd:d9:dd:c25:c25:94de:883a/1282c19:dd:d9:dd:c25:c25:94de:883a
602c19:dd:d9:dd:c25:c25:94de:883b/1282c19:dd:d9:dd:c25:c25:94de:883b
612c19:dd:d9:dd:c25:c25:94de:883c/1282c19:dd:d9:dd:c25:c25:94de:883c
622c19:dd:d9:dd:c25:c25:94de:883d/1282c19:dd:d9:dd:c25:c25:94de:883d
632c19:dd:d9:dd:c25:c25:94de:883e/1282c19:dd:d9:dd:c25:c25:94de:883e
642c19:dd:d9:dd:c25:c25:94de:883f/1282c19:dd:d9:dd:c25:c25:94de:883f
652c19:dd:d9:dd:c25:c25:94de:8840/1282c19:dd:d9:dd:c25:c25:94de:8840
662c19:dd:d9:dd:c25:c25:94de:8841/1282c19:dd:d9:dd:c25:c25:94de:8841
672c19:dd:d9:dd:c25:c25:94de:8842/1282c19:dd:d9:dd:c25:c25:94de:8842
682c19:dd:d9:dd:c25:c25:94de:8843/1282c19:dd:d9:dd:c25:c25:94de:8843
692c19:dd:d9:dd:c25:c25:94de:8844/1282c19:dd:d9:dd:c25:c25:94de:8844
702c19:dd:d9:dd:c25:c25:94de:8845/1282c19:dd:d9:dd:c25:c25:94de:8845
712c19:dd:d9:dd:c25:c25:94de:8846/1282c19:dd:d9:dd:c25:c25:94de:8846
722c19:dd:d9:dd:c25:c25:94de:8847/1282c19:dd:d9:dd:c25:c25:94de:8847
732c19:dd:d9:dd:c25:c25:94de:8848/1282c19:dd:d9:dd:c25:c25:94de:8848
742c19:dd:d9:dd:c25:c25:94de:8849/1282c19:dd:d9:dd:c25:c25:94de:8849
752c19:dd:d9:dd:c25:c25:94de:884a/1282c19:dd:d9:dd:c25:c25:94de:884a
762c19:dd:d9:dd:c25:c25:94de:884b/1282c19:dd:d9:dd:c25:c25:94de:884b
772c19:dd:d9:dd:c25:c25:94de:884c/1282c19:dd:d9:dd:c25:c25:94de:884c
782c19:dd:d9:dd:c25:c25:94de:884d/1282c19:dd:d9:dd:c25:c25:94de:884d
792c19:dd:d9:dd:c25:c25:94de:884e/1282c19:dd:d9:dd:c25:c25:94de:884e
802c19:dd:d9:dd:c25:c25:94de:884f/1282c19:dd:d9:dd:c25:c25:94de:884f
812c19:dd:d9:dd:c25:c25:94de:8850/1282c19:dd:d9:dd:c25:c25:94de:8850
822c19:dd:d9:dd:c25:c25:94de:8851/1282c19:dd:d9:dd:c25:c25:94de:8851
832c19:dd:d9:dd:c25:c25:94de:8852/1282c19:dd:d9:dd:c25:c25:94de:8852
842c19:dd:d9:dd:c25:c25:94de:8853/1282c19:dd:d9:dd:c25:c25:94de:8853
852c19:dd:d9:dd:c25:c25:94de:8854/1282c19:dd:d9:dd:c25:c25:94de:8854
862c19:dd:d9:dd:c25:c25:94de:8855/1282c19:dd:d9:dd:c25:c25:94de:8855
872c19:dd:d9:dd:c25:c25:94de:8856/1282c19:dd:d9:dd:c25:c25:94de:8856
882c19:dd:d9:dd:c25:c25:94de:8857/1282c19:dd:d9:dd:c25:c25:94de:8857
892c19:dd:d9:dd:c25:c25:94de:8858/1282c19:dd:d9:dd:c25:c25:94de:8858
902c19:dd:d9:dd:c25:c25:94de:8859/1282c19:dd:d9:dd:c25:c25:94de:8859
912c19:dd:d9:dd:c25:c25:94de:885a/1282c19:dd:d9:dd:c25:c25:94de:885a
922c19:dd:d9:dd:c25:c25:94de:885b/1282c19:dd:d9:dd:c25:c25:94de:885b
932c19:dd:d9:dd:c25:c25:94de:885c/1282c19:dd:d9:dd:c25:c25:94de:885c
942c19:dd:d9:dd:c25:c25:94de:885d/1282c19:dd:d9:dd:c25:c25:94de:885d
952c19:dd:d9:dd:c25:c25:94de:885e/1282c19:dd:d9:dd:c25:c25:94de:885e
962c19:dd:d9:dd:c25:c25:94de:885f/1282c19:dd:d9:dd:c25:c25:94de:885f
972c19:dd:d9:dd:c25:c25:94de:8860/1282c19:dd:d9:dd:c25:c25:94de:8860
982c19:dd:d9:dd:c25:c25:94de:8861/1282c19:dd:d9:dd:c25:c25:94de:8861
992c19:dd:d9:dd:c25:c25:94de:8862/1282c19:dd:d9:dd:c25:c25:94de:8862
1002c19:dd:d9:dd:c25:c25:94de:8863/1282c19:dd:d9:dd:c25:c25:94de:8863
1012c19:dd:d9:dd:c25:c25:94de:8864/1282c19:dd:d9:dd:c25:c25:94de:8864
1022c19:dd:d9:dd:c25:c25:94de:8865/1282c19:dd:d9:dd:c25:c25:94de:8865
1032c19:dd:d9:dd:c25:c25:94de:8866/1282c19:dd:d9:dd:c25:c25:94de:8866
1042c19:dd:d9:dd:c25:c25:94de:8867/1282c19:dd:d9:dd:c25:c25:94de:8867
1052c19:dd:d9:dd:c25:c25:94de:8868/1282c19:dd:d9:dd:c25:c25:94de:8868
1062c19:dd:d9:dd:c25:c25:94de:8869/1282c19:dd:d9:dd:c25:c25:94de:8869
1072c19:dd:d9:dd:c25:c25:94de:886a/1282c19:dd:d9:dd:c25:c25:94de:886a
1082c19:dd:d9:dd:c25:c25:94de:886b/1282c19:dd:d9:dd:c25:c25:94de:886b
1092c19:dd:d9:dd:c25:c25:94de:886c/1282c19:dd:d9:dd:c25:c25:94de:886c
1102c19:dd:d9:dd:c25:c25:94de:886d/1282c19:dd:d9:dd:c25:c25:94de:886d
1112c19:dd:d9:dd:c25:c25:94de:886e/1282c19:dd:d9:dd:c25:c25:94de:886e
1122c19:dd:d9:dd:c25:c25:94de:886f/1282c19:dd:d9:dd:c25:c25:94de:886f
1132c19:dd:d9:dd:c25:c25:94de:8870/1282c19:dd:d9:dd:c25:c25:94de:8870
1142c19:dd:d9:dd:c25:c25:94de:8871/1282c19:dd:d9:dd:c25:c25:94de:8871
1152c19:dd:d9:dd:c25:c25:94de:8872/1282c19:dd:d9:dd:c25:c25:94de:8872
1162c19:dd:d9:dd:c25:c25:94de:8873/1282c19:dd:d9:dd:c25:c25:94de:8873
1172c19:dd:d9:dd:c25:c25:94de:8874/1282c19:dd:d9:dd:c25:c25:94de:8874
1182c19:dd:d9:dd:c25:c25:94de:8875/1282c19:dd:d9:dd:c25:c25:94de:8875
1192c19:dd:d9:dd:c25:c25:94de:8876/1282c19:dd:d9:dd:c25:c25:94de:8876
1202c19:dd:d9:dd:c25:c25:94de:8877/1282c19:dd:d9:dd:c25:c25:94de:8877
1212c19:dd:d9:dd:c25:c25:94de:8878/1282c19:dd:d9:dd:c25:c25:94de:8878
1222c19:dd:d9:dd:c25:c25:94de:8879/1282c19:dd:d9:dd:c25:c25:94de:8879
1232c19:dd:d9:dd:c25:c25:94de:887a/1282c19:dd:d9:dd:c25:c25:94de:887a
1242c19:dd:d9:dd:c25:c25:94de:887b/1282c19:dd:d9:dd:c25:c25:94de:887b
1252c19:dd:d9:dd:c25:c25:94de:887c/1282c19:dd:d9:dd:c25:c25:94de:887c
1262c19:dd:d9:dd:c25:c25:94de:887d/1282c19:dd:d9:dd:c25:c25:94de:887d
1272c19:dd:d9:dd:c25:c25:94de:887e/1282c19:dd:d9:dd:c25:c25:94de:887e
1282c19:dd:d9:dd:c25:c25:94de:887f/1282c19:dd:d9:dd:c25:c25:94de:887f
1292c19:dd:d9:dd:c25:c25:94de:8880/1282c19:dd:d9:dd:c25:c25:94de:8880
1302c19:dd:d9:dd:c25:c25:94de:8881/1282c19:dd:d9:dd:c25:c25:94de:8881
1312c19:dd:d9:dd:c25:c25:94de:8882/1282c19:dd:d9:dd:c25:c25:94de:8882
1322c19:dd:d9:dd:c25:c25:94de:8883/1282c19:dd:d9:dd:c25:c25:94de:8883
1332c19:dd:d9:dd:c25:c25:94de:8884/1282c19:dd:d9:dd:c25:c25:94de:8884
1342c19:dd:d9:dd:c25:c25:94de:8885/1282c19:dd:d9:dd:c25:c25:94de:8885
1352c19:dd:d9:dd:c25:c25:94de:8886/1282c19:dd:d9:dd:c25:c25:94de:8886
1362c19:dd:d9:dd:c25:c25:94de:8887/1282c19:dd:d9:dd:c25:c25:94de:8887
1372c19:dd:d9:dd:c25:c25:94de:8888/1282c19:dd:d9:dd:c25:c25:94de:8888
1382c19:dd:d9:dd:c25:c25:94de:8889/1282c19:dd:d9:dd:c25:c25:94de:8889
1392c19:dd:d9:dd:c25:c25:94de:888a/1282c19:dd:d9:dd:c25:c25:94de:888a
1402c19:dd:d9:dd:c25:c25:94de:888b/1282c19:dd:d9:dd:c25:c25:94de:888b
1412c19:dd:d9:dd:c25:c25:94de:888c/1282c19:dd:d9:dd:c25:c25:94de:888c
1422c19:dd:d9:dd:c25:c25:94de:888d/1282c19:dd:d9:dd:c25:c25:94de:888d
1432c19:dd:d9:dd:c25:c25:94de:888e/1282c19:dd:d9:dd:c25:c25:94de:888e
1442c19:dd:d9:dd:c25:c25:94de:888f/1282c19:dd:d9:dd:c25:c25:94de:888f
1452c19:dd:d9:dd:c25:c25:94de:8890/1282c19:dd:d9:dd:c25:c25:94de:8890
1462c19:dd:d9:dd:c25:c25:94de:8891/1282c19:dd:d9:dd:c25:c25:94de:8891
1472c19:dd:d9:dd:c25:c25:94de:8892/1282c19:dd:d9:dd:c25:c25:94de:8892
1482c19:dd:d9:dd:c25:c25:94de:8893/1282c19:dd:d9:dd:c25:c25:94de:8893
1492c19:dd:d9:dd:c25:c25:94de:8894/1282c19:dd:d9:dd:c25:c25:94de:8894
1502c19:dd:d9:dd:c25:c25:94de:8895/1282c19:dd:d9:dd:c25:c25:94de:8895
1512c19:dd:d9:dd:c25:c25:94de:8896/1282c19:dd:d9:dd:c25:c25:94de:8896
1522c19:dd:d9:dd:c25:c25:94de:8897/1282c19:dd:d9:dd:c25:c25:94de:8897
1532c19:dd:d9:dd:c25:c25:94de:8898/1282c19:dd:d9:dd:c25:c25:94de:8898
1542c19:dd:d9:dd:c25:c25:94de:8899/1282c19:dd:d9:dd:c25:c25:94de:8899
1552c19:dd:d9:dd:c25:c25:94de:889a/1282c19:dd:d9:dd:c25:c25:94de:889a
1562c19:dd:d9:dd:c25:c25:94de:889b/1282c19:dd:d9:dd:c25:c25:94de:889b
1572c19:dd:d9:dd:c25:c25:94de:889c/1282c19:dd:d9:dd:c25:c25:94de:889c
1582c19:dd:d9:dd:c25:c25:94de:889d/1282c19:dd:d9:dd:c25:c25:94de:889d
1592c19:dd:d9:dd:c25:c25:94de:889e/1282c19:dd:d9:dd:c25:c25:94de:889e
1602c19:dd:d9:dd:c25:c25:94de:889f/1282c19:dd:d9:dd:c25:c25:94de:889f
1612c19:dd:d9:dd:c25:c25:94de:88a0/1282c19:dd:d9:dd:c25:c25:94de:88a0
1622c19:dd:d9:dd:c25:c25:94de:88a1/1282c19:dd:d9:dd:c25:c25:94de:88a1
1632c19:dd:d9:dd:c25:c25:94de:88a2/1282c19:dd:d9:dd:c25:c25:94de:88a2
1642c19:dd:d9:dd:c25:c25:94de:88a3/1282c19:dd:d9:dd:c25:c25:94de:88a3
1652c19:dd:d9:dd:c25:c25:94de:88a4/1282c19:dd:d9:dd:c25:c25:94de:88a4
1662c19:dd:d9:dd:c25:c25:94de:88a5/1282c19:dd:d9:dd:c25:c25:94de:88a5
1672c19:dd:d9:dd:c25:c25:94de:88a6/1282c19:dd:d9:dd:c25:c25:94de:88a6
1682c19:dd:d9:dd:c25:c25:94de:88a7/1282c19:dd:d9:dd:c25:c25:94de:88a7
1692c19:dd:d9:dd:c25:c25:94de:88a8/1282c19:dd:d9:dd:c25:c25:94de:88a8
1702c19:dd:d9:dd:c25:c25:94de:88a9/1282c19:dd:d9:dd:c25:c25:94de:88a9
1712c19:dd:d9:dd:c25:c25:94de:88aa/1282c19:dd:d9:dd:c25:c25:94de:88aa
1722c19:dd:d9:dd:c25:c25:94de:88ab/1282c19:dd:d9:dd:c25:c25:94de:88ab
1732c19:dd:d9:dd:c25:c25:94de:88ac/1282c19:dd:d9:dd:c25:c25:94de:88ac
1742c19:dd:d9:dd:c25:c25:94de:88ad/1282c19:dd:d9:dd:c25:c25:94de:88ad
1752c19:dd:d9:dd:c25:c25:94de:88ae/1282c19:dd:d9:dd:c25:c25:94de:88ae
1762c19:dd:d9:dd:c25:c25:94de:88af/1282c19:dd:d9:dd:c25:c25:94de:88af
1772c19:dd:d9:dd:c25:c25:94de:88b0/1282c19:dd:d9:dd:c25:c25:94de:88b0
1782c19:dd:d9:dd:c25:c25:94de:88b1/1282c19:dd:d9:dd:c25:c25:94de:88b1
1792c19:dd:d9:dd:c25:c25:94de:88b2/1282c19:dd:d9:dd:c25:c25:94de:88b2
1802c19:dd:d9:dd:c25:c25:94de:88b3/1282c19:dd:d9:dd:c25:c25:94de:88b3
1812c19:dd:d9:dd:c25:c25:94de:88b4/1282c19:dd:d9:dd:c25:c25:94de:88b4
1822c19:dd:d9:dd:c25:c25:94de:88b5/1282c19:dd:d9:dd:c25:c25:94de:88b5
1832c19:dd:d9:dd:c25:c25:94de:88b6/1282c19:dd:d9:dd:c25:c25:94de:88b6
1842c19:dd:d9:dd:c25:c25:94de:88b7/1282c19:dd:d9:dd:c25:c25:94de:88b7
1852c19:dd:d9:dd:c25:c25:94de:88b8/1282c19:dd:d9:dd:c25:c25:94de:88b8
1862c19:dd:d9:dd:c25:c25:94de:88b9/1282c19:dd:d9:dd:c25:c25:94de:88b9
1872c19:dd:d9:dd:c25:c25:94de:88ba/1282c19:dd:d9:dd:c25:c25:94de:88ba
1882c19:dd:d9:dd:c25:c25:94de:88bb/1282c19:dd:d9:dd:c25:c25:94de:88bb
1892c19:dd:d9:dd:c25:c25:94de:88bc/1282c19:dd:d9:dd:c25:c25:94de:88bc
1902c19:dd:d9:dd:c25:c25:94de:88bd/1282c19:dd:d9:dd:c25:c25:94de:88bd
1912c19:dd:d9:dd:c25:c25:94de:88be/1282c19:dd:d9:dd:c25:c25:94de:88be
1922c19:dd:d9:dd:c25:c25:94de:88bf/1282c19:dd:d9:dd:c25:c25:94de:88bf
1932c19:dd:d9:dd:c25:c25:94de:88c0/1282c19:dd:d9:dd:c25:c25:94de:88c0
1942c19:dd:d9:dd:c25:c25:94de:88c1/1282c19:dd:d9:dd:c25:c25:94de:88c1
1952c19:dd:d9:dd:c25:c25:94de:88c2/1282c19:dd:d9:dd:c25:c25:94de:88c2
1962c19:dd:d9:dd:c25:c25:94de:88c3/1282c19:dd:d9:dd:c25:c25:94de:88c3
1972c19:dd:d9:dd:c25:c25:94de:88c4/1282c19:dd:d9:dd:c25:c25:94de:88c4
1982c19:dd:d9:dd:c25:c25:94de:88c5/1282c19:dd:d9:dd:c25:c25:94de:88c5
1992c19:dd:d9:dd:c25:c25:94de:88c6/1282c19:dd:d9:dd:c25:c25:94de:88c6
2002c19:dd:d9:dd:c25:c25:94de:88c7/1282c19:dd:d9:dd:c25:c25:94de:88c7
2012c19:dd:d9:dd:c25:c25:94de:88c8/1282c19:dd:d9:dd:c25:c25:94de:88c8
2022c19:dd:d9:dd:c25:c25:94de:88c9/1282c19:dd:d9:dd:c25:c25:94de:88c9
2032c19:dd:d9:dd:c25:c25:94de:88ca/1282c19:dd:d9:dd:c25:c25:94de:88ca
2042c19:dd:d9:dd:c25:c25:94de:88cb/1282c19:dd:d9:dd:c25:c25:94de:88cb
2052c19:dd:d9:dd:c25:c25:94de:88cc/1282c19:dd:d9:dd:c25:c25:94de:88cc
2062c19:dd:d9:dd:c25:c25:94de:88cd/1282c19:dd:d9:dd:c25:c25:94de:88cd
2072c19:dd:d9:dd:c25:c25:94de:88ce/1282c19:dd:d9:dd:c25:c25:94de:88ce
2082c19:dd:d9:dd:c25:c25:94de:88cf/1282c19:dd:d9:dd:c25:c25:94de:88cf
2092c19:dd:d9:dd:c25:c25:94de:88d0/1282c19:dd:d9:dd:c25:c25:94de:88d0
2102c19:dd:d9:dd:c25:c25:94de:88d1/1282c19:dd:d9:dd:c25:c25:94de:88d1
2112c19:dd:d9:dd:c25:c25:94de:88d2/1282c19:dd:d9:dd:c25:c25:94de:88d2
2122c19:dd:d9:dd:c25:c25:94de:88d3/1282c19:dd:d9:dd:c25:c25:94de:88d3
2132c19:dd:d9:dd:c25:c25:94de:88d4/1282c19:dd:d9:dd:c25:c25:94de:88d4
2142c19:dd:d9:dd:c25:c25:94de:88d5/1282c19:dd:d9:dd:c25:c25:94de:88d5
2152c19:dd:d9:dd:c25:c25:94de:88d6/1282c19:dd:d9:dd:c25:c25:94de:88d6
2162c19:dd:d9:dd:c25:c25:94de:88d7/1282c19:dd:d9:dd:c25:c25:94de:88d7
2172c19:dd:d9:dd:c25:c25:94de:88d8/1282c19:dd:d9:dd:c25:c25:94de:88d8
2182c19:dd:d9:dd:c25:c25:94de:88d9/1282c19:dd:d9:dd:c25:c25:94de:88d9
2192c19:dd:d9:dd:c25:c25:94de:88da/1282c19:dd:d9:dd:c25:c25:94de:88da
2202c19:dd:d9:dd:c25:c25:94de:88db/1282c19:dd:d9:dd:c25:c25:94de:88db
2212c19:dd:d9:dd:c25:c25:94de:88dc/1282c19:dd:d9:dd:c25:c25:94de:88dc
2222c19:dd:d9:dd:c25:c25:94de:88dd/1282c19:dd:d9:dd:c25:c25:94de:88dd
2232c19:dd:d9:dd:c25:c25:94de:88de/1282c19:dd:d9:dd:c25:c25:94de:88de
2242c19:dd:d9:dd:c25:c25:94de:88df/1282c19:dd:d9:dd:c25:c25:94de:88df
2252c19:dd:d9:dd:c25:c25:94de:88e0/1282c19:dd:d9:dd:c25:c25:94de:88e0
2262c19:dd:d9:dd:c25:c25:94de:88e1/1282c19:dd:d9:dd:c25:c25:94de:88e1
2272c19:dd:d9:dd:c25:c25:94de:88e2/1282c19:dd:d9:dd:c25:c25:94de:88e2
2282c19:dd:d9:dd:c25:c25:94de:88e3/1282c19:dd:d9:dd:c25:c25:94de:88e3
2292c19:dd:d9:dd:c25:c25:94de:88e4/1282c19:dd:d9:dd:c25:c25:94de:88e4
2302c19:dd:d9:dd:c25:c25:94de:88e5/1282c19:dd:d9:dd:c25:c25:94de:88e5
2312c19:dd:d9:dd:c25:c25:94de:88e6/1282c19:dd:d9:dd:c25:c25:94de:88e6
2322c19:dd:d9:dd:c25:c25:94de:88e7/1282c19:dd:d9:dd:c25:c25:94de:88e7
2332c19:dd:d9:dd:c25:c25:94de:88e8/1282c19:dd:d9:dd:c25:c25:94de:88e8
2342c19:dd:d9:dd:c25:c25:94de:88e9/1282c19:dd:d9:dd:c25:c25:94de:88e9
2352c19:dd:d9:dd:c25:c25:94de:88ea/1282c19:dd:d9:dd:c25:c25:94de:88ea
2362c19:dd:d9:dd:c25:c25:94de:88eb/1282c19:dd:d9:dd:c25:c25:94de:88eb
2372c19:dd:d9:dd:c25:c25:94de:88ec/1282c19:dd:d9:dd:c25:c25:94de:88ec
2382c19:dd:d9:dd:c25:c25:94de:88ed/1282c19:dd:d9:dd:c25:c25:94de:88ed
2392c19:dd:d9:dd:c25:c25:94de:88ee/1282c19:dd:d9:dd:c25:c25:94de:88ee
2402c19:dd:d9:dd:c25:c25:94de:88ef/1282c19:dd:d9:dd:c25:c25:94de:88ef
2412c19:dd:d9:dd:c25:c25:94de:88f0/1282c19:dd:d9:dd:c25:c25:94de:88f0
2422c19:dd:d9:dd:c25:c25:94de:88f1/1282c19:dd:d9:dd:c25:c25:94de:88f1
2432c19:dd:d9:dd:c25:c25:94de:88f2/1282c19:dd:d9:dd:c25:c25:94de:88f2
2442c19:dd:d9:dd:c25:c25:94de:88f3/1282c19:dd:d9:dd:c25:c25:94de:88f3
2452c19:dd:d9:dd:c25:c25:94de:88f4/1282c19:dd:d9:dd:c25:c25:94de:88f4
2462c19:dd:d9:dd:c25:c25:94de:88f5/1282c19:dd:d9:dd:c25:c25:94de:88f5
2472c19:dd:d9:dd:c25:c25:94de:88f6/1282c19:dd:d9:dd:c25:c25:94de:88f6
2482c19:dd:d9:dd:c25:c25:94de:88f7/1282c19:dd:d9:dd:c25:c25:94de:88f7
2492c19:dd:d9:dd:c25:c25:94de:88f8/1282c19:dd:d9:dd:c25:c25:94de:88f8
2502c19:dd:d9:dd:c25:c25:94de:88f9/1282c19:dd:d9:dd:c25:c25:94de:88f9
2512c19:dd:d9:dd:c25:c25:94de:88fa/1282c19:dd:d9:dd:c25:c25:94de:88fa
2522c19:dd:d9:dd:c25:c25:94de:88fb/1282c19:dd:d9:dd:c25:c25:94de:88fb
2532c19:dd:d9:dd:c25:c25:94de:88fc/1282c19:dd:d9:dd:c25:c25:94de:88fc
2542c19:dd:d9:dd:c25:c25:94de:88fd/1282c19:dd:d9:dd:c25:c25:94de:88fd
2552c19:dd:d9:dd:c25:c25:94de:88fe/1282c19:dd:d9:dd:c25:c25:94de:88fe
2562c19:dd:d9:dd:c25:c25:94de:88ff/1282c19:dd:d9:dd:c25:c25:94de:88ff

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.