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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/118
Addresses1,024
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:94de:5800/118
First address
2c19:dd:d9:dd:c25:c25:94de:5800
Last address
2c19:dd:d9:dd:c25:c25:94de:5bff
Addresses
1,024
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:5800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
8.5.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
9.5.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
a.5.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
b.5.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
/118 is not on a 4-bit boundary, so it takes 4 /120 zones.
Split into smaller subnets/128
/119 (2)/120 (4)/121 (8)/122 (16)/124 (64)/127 (512)/128 (1,024)

2c19:dd:d9:dd:c25:c25:94de:5800/118 makes 1,024 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:5800/1282c19:dd:d9:dd:c25:c25:94de:5800
22c19:dd:d9:dd:c25:c25:94de:5801/1282c19:dd:d9:dd:c25:c25:94de:5801
32c19:dd:d9:dd:c25:c25:94de:5802/1282c19:dd:d9:dd:c25:c25:94de:5802
42c19:dd:d9:dd:c25:c25:94de:5803/1282c19:dd:d9:dd:c25:c25:94de:5803
52c19:dd:d9:dd:c25:c25:94de:5804/1282c19:dd:d9:dd:c25:c25:94de:5804
62c19:dd:d9:dd:c25:c25:94de:5805/1282c19:dd:d9:dd:c25:c25:94de:5805
72c19:dd:d9:dd:c25:c25:94de:5806/1282c19:dd:d9:dd:c25:c25:94de:5806
82c19:dd:d9:dd:c25:c25:94de:5807/1282c19:dd:d9:dd:c25:c25:94de:5807
92c19:dd:d9:dd:c25:c25:94de:5808/1282c19:dd:d9:dd:c25:c25:94de:5808
102c19:dd:d9:dd:c25:c25:94de:5809/1282c19:dd:d9:dd:c25:c25:94de:5809
112c19:dd:d9:dd:c25:c25:94de:580a/1282c19:dd:d9:dd:c25:c25:94de:580a
122c19:dd:d9:dd:c25:c25:94de:580b/1282c19:dd:d9:dd:c25:c25:94de:580b
132c19:dd:d9:dd:c25:c25:94de:580c/1282c19:dd:d9:dd:c25:c25:94de:580c
142c19:dd:d9:dd:c25:c25:94de:580d/1282c19:dd:d9:dd:c25:c25:94de:580d
152c19:dd:d9:dd:c25:c25:94de:580e/1282c19:dd:d9:dd:c25:c25:94de:580e
162c19:dd:d9:dd:c25:c25:94de:580f/1282c19:dd:d9:dd:c25:c25:94de:580f
172c19:dd:d9:dd:c25:c25:94de:5810/1282c19:dd:d9:dd:c25:c25:94de:5810
182c19:dd:d9:dd:c25:c25:94de:5811/1282c19:dd:d9:dd:c25:c25:94de:5811
192c19:dd:d9:dd:c25:c25:94de:5812/1282c19:dd:d9:dd:c25:c25:94de:5812
202c19:dd:d9:dd:c25:c25:94de:5813/1282c19:dd:d9:dd:c25:c25:94de:5813
212c19:dd:d9:dd:c25:c25:94de:5814/1282c19:dd:d9:dd:c25:c25:94de:5814
222c19:dd:d9:dd:c25:c25:94de:5815/1282c19:dd:d9:dd:c25:c25:94de:5815
232c19:dd:d9:dd:c25:c25:94de:5816/1282c19:dd:d9:dd:c25:c25:94de:5816
242c19:dd:d9:dd:c25:c25:94de:5817/1282c19:dd:d9:dd:c25:c25:94de:5817
252c19:dd:d9:dd:c25:c25:94de:5818/1282c19:dd:d9:dd:c25:c25:94de:5818
262c19:dd:d9:dd:c25:c25:94de:5819/1282c19:dd:d9:dd:c25:c25:94de:5819
272c19:dd:d9:dd:c25:c25:94de:581a/1282c19:dd:d9:dd:c25:c25:94de:581a
282c19:dd:d9:dd:c25:c25:94de:581b/1282c19:dd:d9:dd:c25:c25:94de:581b
292c19:dd:d9:dd:c25:c25:94de:581c/1282c19:dd:d9:dd:c25:c25:94de:581c
302c19:dd:d9:dd:c25:c25:94de:581d/1282c19:dd:d9:dd:c25:c25:94de:581d
312c19:dd:d9:dd:c25:c25:94de:581e/1282c19:dd:d9:dd:c25:c25:94de:581e
322c19:dd:d9:dd:c25:c25:94de:581f/1282c19:dd:d9:dd:c25:c25:94de:581f
332c19:dd:d9:dd:c25:c25:94de:5820/1282c19:dd:d9:dd:c25:c25:94de:5820
342c19:dd:d9:dd:c25:c25:94de:5821/1282c19:dd:d9:dd:c25:c25:94de:5821
352c19:dd:d9:dd:c25:c25:94de:5822/1282c19:dd:d9:dd:c25:c25:94de:5822
362c19:dd:d9:dd:c25:c25:94de:5823/1282c19:dd:d9:dd:c25:c25:94de:5823
372c19:dd:d9:dd:c25:c25:94de:5824/1282c19:dd:d9:dd:c25:c25:94de:5824
382c19:dd:d9:dd:c25:c25:94de:5825/1282c19:dd:d9:dd:c25:c25:94de:5825
392c19:dd:d9:dd:c25:c25:94de:5826/1282c19:dd:d9:dd:c25:c25:94de:5826
402c19:dd:d9:dd:c25:c25:94de:5827/1282c19:dd:d9:dd:c25:c25:94de:5827
412c19:dd:d9:dd:c25:c25:94de:5828/1282c19:dd:d9:dd:c25:c25:94de:5828
422c19:dd:d9:dd:c25:c25:94de:5829/1282c19:dd:d9:dd:c25:c25:94de:5829
432c19:dd:d9:dd:c25:c25:94de:582a/1282c19:dd:d9:dd:c25:c25:94de:582a
442c19:dd:d9:dd:c25:c25:94de:582b/1282c19:dd:d9:dd:c25:c25:94de:582b
452c19:dd:d9:dd:c25:c25:94de:582c/1282c19:dd:d9:dd:c25:c25:94de:582c
462c19:dd:d9:dd:c25:c25:94de:582d/1282c19:dd:d9:dd:c25:c25:94de:582d
472c19:dd:d9:dd:c25:c25:94de:582e/1282c19:dd:d9:dd:c25:c25:94de:582e
482c19:dd:d9:dd:c25:c25:94de:582f/1282c19:dd:d9:dd:c25:c25:94de:582f
492c19:dd:d9:dd:c25:c25:94de:5830/1282c19:dd:d9:dd:c25:c25:94de:5830
502c19:dd:d9:dd:c25:c25:94de:5831/1282c19:dd:d9:dd:c25:c25:94de:5831
512c19:dd:d9:dd:c25:c25:94de:5832/1282c19:dd:d9:dd:c25:c25:94de:5832
522c19:dd:d9:dd:c25:c25:94de:5833/1282c19:dd:d9:dd:c25:c25:94de:5833
532c19:dd:d9:dd:c25:c25:94de:5834/1282c19:dd:d9:dd:c25:c25:94de:5834
542c19:dd:d9:dd:c25:c25:94de:5835/1282c19:dd:d9:dd:c25:c25:94de:5835
552c19:dd:d9:dd:c25:c25:94de:5836/1282c19:dd:d9:dd:c25:c25:94de:5836
562c19:dd:d9:dd:c25:c25:94de:5837/1282c19:dd:d9:dd:c25:c25:94de:5837
572c19:dd:d9:dd:c25:c25:94de:5838/1282c19:dd:d9:dd:c25:c25:94de:5838
582c19:dd:d9:dd:c25:c25:94de:5839/1282c19:dd:d9:dd:c25:c25:94de:5839
592c19:dd:d9:dd:c25:c25:94de:583a/1282c19:dd:d9:dd:c25:c25:94de:583a
602c19:dd:d9:dd:c25:c25:94de:583b/1282c19:dd:d9:dd:c25:c25:94de:583b
612c19:dd:d9:dd:c25:c25:94de:583c/1282c19:dd:d9:dd:c25:c25:94de:583c
622c19:dd:d9:dd:c25:c25:94de:583d/1282c19:dd:d9:dd:c25:c25:94de:583d
632c19:dd:d9:dd:c25:c25:94de:583e/1282c19:dd:d9:dd:c25:c25:94de:583e
642c19:dd:d9:dd:c25:c25:94de:583f/1282c19:dd:d9:dd:c25:c25:94de:583f
652c19:dd:d9:dd:c25:c25:94de:5840/1282c19:dd:d9:dd:c25:c25:94de:5840
662c19:dd:d9:dd:c25:c25:94de:5841/1282c19:dd:d9:dd:c25:c25:94de:5841
672c19:dd:d9:dd:c25:c25:94de:5842/1282c19:dd:d9:dd:c25:c25:94de:5842
682c19:dd:d9:dd:c25:c25:94de:5843/1282c19:dd:d9:dd:c25:c25:94de:5843
692c19:dd:d9:dd:c25:c25:94de:5844/1282c19:dd:d9:dd:c25:c25:94de:5844
702c19:dd:d9:dd:c25:c25:94de:5845/1282c19:dd:d9:dd:c25:c25:94de:5845
712c19:dd:d9:dd:c25:c25:94de:5846/1282c19:dd:d9:dd:c25:c25:94de:5846
722c19:dd:d9:dd:c25:c25:94de:5847/1282c19:dd:d9:dd:c25:c25:94de:5847
732c19:dd:d9:dd:c25:c25:94de:5848/1282c19:dd:d9:dd:c25:c25:94de:5848
742c19:dd:d9:dd:c25:c25:94de:5849/1282c19:dd:d9:dd:c25:c25:94de:5849
752c19:dd:d9:dd:c25:c25:94de:584a/1282c19:dd:d9:dd:c25:c25:94de:584a
762c19:dd:d9:dd:c25:c25:94de:584b/1282c19:dd:d9:dd:c25:c25:94de:584b
772c19:dd:d9:dd:c25:c25:94de:584c/1282c19:dd:d9:dd:c25:c25:94de:584c
782c19:dd:d9:dd:c25:c25:94de:584d/1282c19:dd:d9:dd:c25:c25:94de:584d
792c19:dd:d9:dd:c25:c25:94de:584e/1282c19:dd:d9:dd:c25:c25:94de:584e
802c19:dd:d9:dd:c25:c25:94de:584f/1282c19:dd:d9:dd:c25:c25:94de:584f
812c19:dd:d9:dd:c25:c25:94de:5850/1282c19:dd:d9:dd:c25:c25:94de:5850
822c19:dd:d9:dd:c25:c25:94de:5851/1282c19:dd:d9:dd:c25:c25:94de:5851
832c19:dd:d9:dd:c25:c25:94de:5852/1282c19:dd:d9:dd:c25:c25:94de:5852
842c19:dd:d9:dd:c25:c25:94de:5853/1282c19:dd:d9:dd:c25:c25:94de:5853
852c19:dd:d9:dd:c25:c25:94de:5854/1282c19:dd:d9:dd:c25:c25:94de:5854
862c19:dd:d9:dd:c25:c25:94de:5855/1282c19:dd:d9:dd:c25:c25:94de:5855
872c19:dd:d9:dd:c25:c25:94de:5856/1282c19:dd:d9:dd:c25:c25:94de:5856
882c19:dd:d9:dd:c25:c25:94de:5857/1282c19:dd:d9:dd:c25:c25:94de:5857
892c19:dd:d9:dd:c25:c25:94de:5858/1282c19:dd:d9:dd:c25:c25:94de:5858
902c19:dd:d9:dd:c25:c25:94de:5859/1282c19:dd:d9:dd:c25:c25:94de:5859
912c19:dd:d9:dd:c25:c25:94de:585a/1282c19:dd:d9:dd:c25:c25:94de:585a
922c19:dd:d9:dd:c25:c25:94de:585b/1282c19:dd:d9:dd:c25:c25:94de:585b
932c19:dd:d9:dd:c25:c25:94de:585c/1282c19:dd:d9:dd:c25:c25:94de:585c
942c19:dd:d9:dd:c25:c25:94de:585d/1282c19:dd:d9:dd:c25:c25:94de:585d
952c19:dd:d9:dd:c25:c25:94de:585e/1282c19:dd:d9:dd:c25:c25:94de:585e
962c19:dd:d9:dd:c25:c25:94de:585f/1282c19:dd:d9:dd:c25:c25:94de:585f
972c19:dd:d9:dd:c25:c25:94de:5860/1282c19:dd:d9:dd:c25:c25:94de:5860
982c19:dd:d9:dd:c25:c25:94de:5861/1282c19:dd:d9:dd:c25:c25:94de:5861
992c19:dd:d9:dd:c25:c25:94de:5862/1282c19:dd:d9:dd:c25:c25:94de:5862
1002c19:dd:d9:dd:c25:c25:94de:5863/1282c19:dd:d9:dd:c25:c25:94de:5863
1012c19:dd:d9:dd:c25:c25:94de:5864/1282c19:dd:d9:dd:c25:c25:94de:5864
1022c19:dd:d9:dd:c25:c25:94de:5865/1282c19:dd:d9:dd:c25:c25:94de:5865
1032c19:dd:d9:dd:c25:c25:94de:5866/1282c19:dd:d9:dd:c25:c25:94de:5866
1042c19:dd:d9:dd:c25:c25:94de:5867/1282c19:dd:d9:dd:c25:c25:94de:5867
1052c19:dd:d9:dd:c25:c25:94de:5868/1282c19:dd:d9:dd:c25:c25:94de:5868
1062c19:dd:d9:dd:c25:c25:94de:5869/1282c19:dd:d9:dd:c25:c25:94de:5869
1072c19:dd:d9:dd:c25:c25:94de:586a/1282c19:dd:d9:dd:c25:c25:94de:586a
1082c19:dd:d9:dd:c25:c25:94de:586b/1282c19:dd:d9:dd:c25:c25:94de:586b
1092c19:dd:d9:dd:c25:c25:94de:586c/1282c19:dd:d9:dd:c25:c25:94de:586c
1102c19:dd:d9:dd:c25:c25:94de:586d/1282c19:dd:d9:dd:c25:c25:94de:586d
1112c19:dd:d9:dd:c25:c25:94de:586e/1282c19:dd:d9:dd:c25:c25:94de:586e
1122c19:dd:d9:dd:c25:c25:94de:586f/1282c19:dd:d9:dd:c25:c25:94de:586f
1132c19:dd:d9:dd:c25:c25:94de:5870/1282c19:dd:d9:dd:c25:c25:94de:5870
1142c19:dd:d9:dd:c25:c25:94de:5871/1282c19:dd:d9:dd:c25:c25:94de:5871
1152c19:dd:d9:dd:c25:c25:94de:5872/1282c19:dd:d9:dd:c25:c25:94de:5872
1162c19:dd:d9:dd:c25:c25:94de:5873/1282c19:dd:d9:dd:c25:c25:94de:5873
1172c19:dd:d9:dd:c25:c25:94de:5874/1282c19:dd:d9:dd:c25:c25:94de:5874
1182c19:dd:d9:dd:c25:c25:94de:5875/1282c19:dd:d9:dd:c25:c25:94de:5875
1192c19:dd:d9:dd:c25:c25:94de:5876/1282c19:dd:d9:dd:c25:c25:94de:5876
1202c19:dd:d9:dd:c25:c25:94de:5877/1282c19:dd:d9:dd:c25:c25:94de:5877
1212c19:dd:d9:dd:c25:c25:94de:5878/1282c19:dd:d9:dd:c25:c25:94de:5878
1222c19:dd:d9:dd:c25:c25:94de:5879/1282c19:dd:d9:dd:c25:c25:94de:5879
1232c19:dd:d9:dd:c25:c25:94de:587a/1282c19:dd:d9:dd:c25:c25:94de:587a
1242c19:dd:d9:dd:c25:c25:94de:587b/1282c19:dd:d9:dd:c25:c25:94de:587b
1252c19:dd:d9:dd:c25:c25:94de:587c/1282c19:dd:d9:dd:c25:c25:94de:587c
1262c19:dd:d9:dd:c25:c25:94de:587d/1282c19:dd:d9:dd:c25:c25:94de:587d
1272c19:dd:d9:dd:c25:c25:94de:587e/1282c19:dd:d9:dd:c25:c25:94de:587e
1282c19:dd:d9:dd:c25:c25:94de:587f/1282c19:dd:d9:dd:c25:c25:94de:587f
1292c19:dd:d9:dd:c25:c25:94de:5880/1282c19:dd:d9:dd:c25:c25:94de:5880
1302c19:dd:d9:dd:c25:c25:94de:5881/1282c19:dd:d9:dd:c25:c25:94de:5881
1312c19:dd:d9:dd:c25:c25:94de:5882/1282c19:dd:d9:dd:c25:c25:94de:5882
1322c19:dd:d9:dd:c25:c25:94de:5883/1282c19:dd:d9:dd:c25:c25:94de:5883
1332c19:dd:d9:dd:c25:c25:94de:5884/1282c19:dd:d9:dd:c25:c25:94de:5884
1342c19:dd:d9:dd:c25:c25:94de:5885/1282c19:dd:d9:dd:c25:c25:94de:5885
1352c19:dd:d9:dd:c25:c25:94de:5886/1282c19:dd:d9:dd:c25:c25:94de:5886
1362c19:dd:d9:dd:c25:c25:94de:5887/1282c19:dd:d9:dd:c25:c25:94de:5887
1372c19:dd:d9:dd:c25:c25:94de:5888/1282c19:dd:d9:dd:c25:c25:94de:5888
1382c19:dd:d9:dd:c25:c25:94de:5889/1282c19:dd:d9:dd:c25:c25:94de:5889
1392c19:dd:d9:dd:c25:c25:94de:588a/1282c19:dd:d9:dd:c25:c25:94de:588a
1402c19:dd:d9:dd:c25:c25:94de:588b/1282c19:dd:d9:dd:c25:c25:94de:588b
1412c19:dd:d9:dd:c25:c25:94de:588c/1282c19:dd:d9:dd:c25:c25:94de:588c
1422c19:dd:d9:dd:c25:c25:94de:588d/1282c19:dd:d9:dd:c25:c25:94de:588d
1432c19:dd:d9:dd:c25:c25:94de:588e/1282c19:dd:d9:dd:c25:c25:94de:588e
1442c19:dd:d9:dd:c25:c25:94de:588f/1282c19:dd:d9:dd:c25:c25:94de:588f
1452c19:dd:d9:dd:c25:c25:94de:5890/1282c19:dd:d9:dd:c25:c25:94de:5890
1462c19:dd:d9:dd:c25:c25:94de:5891/1282c19:dd:d9:dd:c25:c25:94de:5891
1472c19:dd:d9:dd:c25:c25:94de:5892/1282c19:dd:d9:dd:c25:c25:94de:5892
1482c19:dd:d9:dd:c25:c25:94de:5893/1282c19:dd:d9:dd:c25:c25:94de:5893
1492c19:dd:d9:dd:c25:c25:94de:5894/1282c19:dd:d9:dd:c25:c25:94de:5894
1502c19:dd:d9:dd:c25:c25:94de:5895/1282c19:dd:d9:dd:c25:c25:94de:5895
1512c19:dd:d9:dd:c25:c25:94de:5896/1282c19:dd:d9:dd:c25:c25:94de:5896
1522c19:dd:d9:dd:c25:c25:94de:5897/1282c19:dd:d9:dd:c25:c25:94de:5897
1532c19:dd:d9:dd:c25:c25:94de:5898/1282c19:dd:d9:dd:c25:c25:94de:5898
1542c19:dd:d9:dd:c25:c25:94de:5899/1282c19:dd:d9:dd:c25:c25:94de:5899
1552c19:dd:d9:dd:c25:c25:94de:589a/1282c19:dd:d9:dd:c25:c25:94de:589a
1562c19:dd:d9:dd:c25:c25:94de:589b/1282c19:dd:d9:dd:c25:c25:94de:589b
1572c19:dd:d9:dd:c25:c25:94de:589c/1282c19:dd:d9:dd:c25:c25:94de:589c
1582c19:dd:d9:dd:c25:c25:94de:589d/1282c19:dd:d9:dd:c25:c25:94de:589d
1592c19:dd:d9:dd:c25:c25:94de:589e/1282c19:dd:d9:dd:c25:c25:94de:589e
1602c19:dd:d9:dd:c25:c25:94de:589f/1282c19:dd:d9:dd:c25:c25:94de:589f
1612c19:dd:d9:dd:c25:c25:94de:58a0/1282c19:dd:d9:dd:c25:c25:94de:58a0
1622c19:dd:d9:dd:c25:c25:94de:58a1/1282c19:dd:d9:dd:c25:c25:94de:58a1
1632c19:dd:d9:dd:c25:c25:94de:58a2/1282c19:dd:d9:dd:c25:c25:94de:58a2
1642c19:dd:d9:dd:c25:c25:94de:58a3/1282c19:dd:d9:dd:c25:c25:94de:58a3
1652c19:dd:d9:dd:c25:c25:94de:58a4/1282c19:dd:d9:dd:c25:c25:94de:58a4
1662c19:dd:d9:dd:c25:c25:94de:58a5/1282c19:dd:d9:dd:c25:c25:94de:58a5
1672c19:dd:d9:dd:c25:c25:94de:58a6/1282c19:dd:d9:dd:c25:c25:94de:58a6
1682c19:dd:d9:dd:c25:c25:94de:58a7/1282c19:dd:d9:dd:c25:c25:94de:58a7
1692c19:dd:d9:dd:c25:c25:94de:58a8/1282c19:dd:d9:dd:c25:c25:94de:58a8
1702c19:dd:d9:dd:c25:c25:94de:58a9/1282c19:dd:d9:dd:c25:c25:94de:58a9
1712c19:dd:d9:dd:c25:c25:94de:58aa/1282c19:dd:d9:dd:c25:c25:94de:58aa
1722c19:dd:d9:dd:c25:c25:94de:58ab/1282c19:dd:d9:dd:c25:c25:94de:58ab
1732c19:dd:d9:dd:c25:c25:94de:58ac/1282c19:dd:d9:dd:c25:c25:94de:58ac
1742c19:dd:d9:dd:c25:c25:94de:58ad/1282c19:dd:d9:dd:c25:c25:94de:58ad
1752c19:dd:d9:dd:c25:c25:94de:58ae/1282c19:dd:d9:dd:c25:c25:94de:58ae
1762c19:dd:d9:dd:c25:c25:94de:58af/1282c19:dd:d9:dd:c25:c25:94de:58af
1772c19:dd:d9:dd:c25:c25:94de:58b0/1282c19:dd:d9:dd:c25:c25:94de:58b0
1782c19:dd:d9:dd:c25:c25:94de:58b1/1282c19:dd:d9:dd:c25:c25:94de:58b1
1792c19:dd:d9:dd:c25:c25:94de:58b2/1282c19:dd:d9:dd:c25:c25:94de:58b2
1802c19:dd:d9:dd:c25:c25:94de:58b3/1282c19:dd:d9:dd:c25:c25:94de:58b3
1812c19:dd:d9:dd:c25:c25:94de:58b4/1282c19:dd:d9:dd:c25:c25:94de:58b4
1822c19:dd:d9:dd:c25:c25:94de:58b5/1282c19:dd:d9:dd:c25:c25:94de:58b5
1832c19:dd:d9:dd:c25:c25:94de:58b6/1282c19:dd:d9:dd:c25:c25:94de:58b6
1842c19:dd:d9:dd:c25:c25:94de:58b7/1282c19:dd:d9:dd:c25:c25:94de:58b7
1852c19:dd:d9:dd:c25:c25:94de:58b8/1282c19:dd:d9:dd:c25:c25:94de:58b8
1862c19:dd:d9:dd:c25:c25:94de:58b9/1282c19:dd:d9:dd:c25:c25:94de:58b9
1872c19:dd:d9:dd:c25:c25:94de:58ba/1282c19:dd:d9:dd:c25:c25:94de:58ba
1882c19:dd:d9:dd:c25:c25:94de:58bb/1282c19:dd:d9:dd:c25:c25:94de:58bb
1892c19:dd:d9:dd:c25:c25:94de:58bc/1282c19:dd:d9:dd:c25:c25:94de:58bc
1902c19:dd:d9:dd:c25:c25:94de:58bd/1282c19:dd:d9:dd:c25:c25:94de:58bd
1912c19:dd:d9:dd:c25:c25:94de:58be/1282c19:dd:d9:dd:c25:c25:94de:58be
1922c19:dd:d9:dd:c25:c25:94de:58bf/1282c19:dd:d9:dd:c25:c25:94de:58bf
1932c19:dd:d9:dd:c25:c25:94de:58c0/1282c19:dd:d9:dd:c25:c25:94de:58c0
1942c19:dd:d9:dd:c25:c25:94de:58c1/1282c19:dd:d9:dd:c25:c25:94de:58c1
1952c19:dd:d9:dd:c25:c25:94de:58c2/1282c19:dd:d9:dd:c25:c25:94de:58c2
1962c19:dd:d9:dd:c25:c25:94de:58c3/1282c19:dd:d9:dd:c25:c25:94de:58c3
1972c19:dd:d9:dd:c25:c25:94de:58c4/1282c19:dd:d9:dd:c25:c25:94de:58c4
1982c19:dd:d9:dd:c25:c25:94de:58c5/1282c19:dd:d9:dd:c25:c25:94de:58c5
1992c19:dd:d9:dd:c25:c25:94de:58c6/1282c19:dd:d9:dd:c25:c25:94de:58c6
2002c19:dd:d9:dd:c25:c25:94de:58c7/1282c19:dd:d9:dd:c25:c25:94de:58c7
2012c19:dd:d9:dd:c25:c25:94de:58c8/1282c19:dd:d9:dd:c25:c25:94de:58c8
2022c19:dd:d9:dd:c25:c25:94de:58c9/1282c19:dd:d9:dd:c25:c25:94de:58c9
2032c19:dd:d9:dd:c25:c25:94de:58ca/1282c19:dd:d9:dd:c25:c25:94de:58ca
2042c19:dd:d9:dd:c25:c25:94de:58cb/1282c19:dd:d9:dd:c25:c25:94de:58cb
2052c19:dd:d9:dd:c25:c25:94de:58cc/1282c19:dd:d9:dd:c25:c25:94de:58cc
2062c19:dd:d9:dd:c25:c25:94de:58cd/1282c19:dd:d9:dd:c25:c25:94de:58cd
2072c19:dd:d9:dd:c25:c25:94de:58ce/1282c19:dd:d9:dd:c25:c25:94de:58ce
2082c19:dd:d9:dd:c25:c25:94de:58cf/1282c19:dd:d9:dd:c25:c25:94de:58cf
2092c19:dd:d9:dd:c25:c25:94de:58d0/1282c19:dd:d9:dd:c25:c25:94de:58d0
2102c19:dd:d9:dd:c25:c25:94de:58d1/1282c19:dd:d9:dd:c25:c25:94de:58d1
2112c19:dd:d9:dd:c25:c25:94de:58d2/1282c19:dd:d9:dd:c25:c25:94de:58d2
2122c19:dd:d9:dd:c25:c25:94de:58d3/1282c19:dd:d9:dd:c25:c25:94de:58d3
2132c19:dd:d9:dd:c25:c25:94de:58d4/1282c19:dd:d9:dd:c25:c25:94de:58d4
2142c19:dd:d9:dd:c25:c25:94de:58d5/1282c19:dd:d9:dd:c25:c25:94de:58d5
2152c19:dd:d9:dd:c25:c25:94de:58d6/1282c19:dd:d9:dd:c25:c25:94de:58d6
2162c19:dd:d9:dd:c25:c25:94de:58d7/1282c19:dd:d9:dd:c25:c25:94de:58d7
2172c19:dd:d9:dd:c25:c25:94de:58d8/1282c19:dd:d9:dd:c25:c25:94de:58d8
2182c19:dd:d9:dd:c25:c25:94de:58d9/1282c19:dd:d9:dd:c25:c25:94de:58d9
2192c19:dd:d9:dd:c25:c25:94de:58da/1282c19:dd:d9:dd:c25:c25:94de:58da
2202c19:dd:d9:dd:c25:c25:94de:58db/1282c19:dd:d9:dd:c25:c25:94de:58db
2212c19:dd:d9:dd:c25:c25:94de:58dc/1282c19:dd:d9:dd:c25:c25:94de:58dc
2222c19:dd:d9:dd:c25:c25:94de:58dd/1282c19:dd:d9:dd:c25:c25:94de:58dd
2232c19:dd:d9:dd:c25:c25:94de:58de/1282c19:dd:d9:dd:c25:c25:94de:58de
2242c19:dd:d9:dd:c25:c25:94de:58df/1282c19:dd:d9:dd:c25:c25:94de:58df
2252c19:dd:d9:dd:c25:c25:94de:58e0/1282c19:dd:d9:dd:c25:c25:94de:58e0
2262c19:dd:d9:dd:c25:c25:94de:58e1/1282c19:dd:d9:dd:c25:c25:94de:58e1
2272c19:dd:d9:dd:c25:c25:94de:58e2/1282c19:dd:d9:dd:c25:c25:94de:58e2
2282c19:dd:d9:dd:c25:c25:94de:58e3/1282c19:dd:d9:dd:c25:c25:94de:58e3
2292c19:dd:d9:dd:c25:c25:94de:58e4/1282c19:dd:d9:dd:c25:c25:94de:58e4
2302c19:dd:d9:dd:c25:c25:94de:58e5/1282c19:dd:d9:dd:c25:c25:94de:58e5
2312c19:dd:d9:dd:c25:c25:94de:58e6/1282c19:dd:d9:dd:c25:c25:94de:58e6
2322c19:dd:d9:dd:c25:c25:94de:58e7/1282c19:dd:d9:dd:c25:c25:94de:58e7
2332c19:dd:d9:dd:c25:c25:94de:58e8/1282c19:dd:d9:dd:c25:c25:94de:58e8
2342c19:dd:d9:dd:c25:c25:94de:58e9/1282c19:dd:d9:dd:c25:c25:94de:58e9
2352c19:dd:d9:dd:c25:c25:94de:58ea/1282c19:dd:d9:dd:c25:c25:94de:58ea
2362c19:dd:d9:dd:c25:c25:94de:58eb/1282c19:dd:d9:dd:c25:c25:94de:58eb
2372c19:dd:d9:dd:c25:c25:94de:58ec/1282c19:dd:d9:dd:c25:c25:94de:58ec
2382c19:dd:d9:dd:c25:c25:94de:58ed/1282c19:dd:d9:dd:c25:c25:94de:58ed
2392c19:dd:d9:dd:c25:c25:94de:58ee/1282c19:dd:d9:dd:c25:c25:94de:58ee
2402c19:dd:d9:dd:c25:c25:94de:58ef/1282c19:dd:d9:dd:c25:c25:94de:58ef
2412c19:dd:d9:dd:c25:c25:94de:58f0/1282c19:dd:d9:dd:c25:c25:94de:58f0
2422c19:dd:d9:dd:c25:c25:94de:58f1/1282c19:dd:d9:dd:c25:c25:94de:58f1
2432c19:dd:d9:dd:c25:c25:94de:58f2/1282c19:dd:d9:dd:c25:c25:94de:58f2
2442c19:dd:d9:dd:c25:c25:94de:58f3/1282c19:dd:d9:dd:c25:c25:94de:58f3
2452c19:dd:d9:dd:c25:c25:94de:58f4/1282c19:dd:d9:dd:c25:c25:94de:58f4
2462c19:dd:d9:dd:c25:c25:94de:58f5/1282c19:dd:d9:dd:c25:c25:94de:58f5
2472c19:dd:d9:dd:c25:c25:94de:58f6/1282c19:dd:d9:dd:c25:c25:94de:58f6
2482c19:dd:d9:dd:c25:c25:94de:58f7/1282c19:dd:d9:dd:c25:c25:94de:58f7
2492c19:dd:d9:dd:c25:c25:94de:58f8/1282c19:dd:d9:dd:c25:c25:94de:58f8
2502c19:dd:d9:dd:c25:c25:94de:58f9/1282c19:dd:d9:dd:c25:c25:94de:58f9
2512c19:dd:d9:dd:c25:c25:94de:58fa/1282c19:dd:d9:dd:c25:c25:94de:58fa
2522c19:dd:d9:dd:c25:c25:94de:58fb/1282c19:dd:d9:dd:c25:c25:94de:58fb
2532c19:dd:d9:dd:c25:c25:94de:58fc/1282c19:dd:d9:dd:c25:c25:94de:58fc
2542c19:dd:d9:dd:c25:c25:94de:58fd/1282c19:dd:d9:dd:c25:c25:94de:58fd
2552c19:dd:d9:dd:c25:c25:94de:58fe/1282c19:dd:d9:dd:c25:c25:94de:58fe
2562c19:dd:d9:dd:c25:c25:94de:58ff/1282c19:dd:d9:dd:c25:c25:94de:58ff

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.