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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:c25a:d00a:7800/120
First address
2c19:dd:d9:dd:c25:c25a:d00a:7800
Last address
2c19:dd:d9:dd:c25:c25a:d00a:78ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25a:d00a:7800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
8.7.a.0.0.d.a.5.2.c.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:c25a:d00a:7800/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25a:d00a:7800/1282c19:dd:d9:dd:c25:c25a:d00a:7800
22c19:dd:d9:dd:c25:c25a:d00a:7801/1282c19:dd:d9:dd:c25:c25a:d00a:7801
32c19:dd:d9:dd:c25:c25a:d00a:7802/1282c19:dd:d9:dd:c25:c25a:d00a:7802
42c19:dd:d9:dd:c25:c25a:d00a:7803/1282c19:dd:d9:dd:c25:c25a:d00a:7803
52c19:dd:d9:dd:c25:c25a:d00a:7804/1282c19:dd:d9:dd:c25:c25a:d00a:7804
62c19:dd:d9:dd:c25:c25a:d00a:7805/1282c19:dd:d9:dd:c25:c25a:d00a:7805
72c19:dd:d9:dd:c25:c25a:d00a:7806/1282c19:dd:d9:dd:c25:c25a:d00a:7806
82c19:dd:d9:dd:c25:c25a:d00a:7807/1282c19:dd:d9:dd:c25:c25a:d00a:7807
92c19:dd:d9:dd:c25:c25a:d00a:7808/1282c19:dd:d9:dd:c25:c25a:d00a:7808
102c19:dd:d9:dd:c25:c25a:d00a:7809/1282c19:dd:d9:dd:c25:c25a:d00a:7809
112c19:dd:d9:dd:c25:c25a:d00a:780a/1282c19:dd:d9:dd:c25:c25a:d00a:780a
122c19:dd:d9:dd:c25:c25a:d00a:780b/1282c19:dd:d9:dd:c25:c25a:d00a:780b
132c19:dd:d9:dd:c25:c25a:d00a:780c/1282c19:dd:d9:dd:c25:c25a:d00a:780c
142c19:dd:d9:dd:c25:c25a:d00a:780d/1282c19:dd:d9:dd:c25:c25a:d00a:780d
152c19:dd:d9:dd:c25:c25a:d00a:780e/1282c19:dd:d9:dd:c25:c25a:d00a:780e
162c19:dd:d9:dd:c25:c25a:d00a:780f/1282c19:dd:d9:dd:c25:c25a:d00a:780f
172c19:dd:d9:dd:c25:c25a:d00a:7810/1282c19:dd:d9:dd:c25:c25a:d00a:7810
182c19:dd:d9:dd:c25:c25a:d00a:7811/1282c19:dd:d9:dd:c25:c25a:d00a:7811
192c19:dd:d9:dd:c25:c25a:d00a:7812/1282c19:dd:d9:dd:c25:c25a:d00a:7812
202c19:dd:d9:dd:c25:c25a:d00a:7813/1282c19:dd:d9:dd:c25:c25a:d00a:7813
212c19:dd:d9:dd:c25:c25a:d00a:7814/1282c19:dd:d9:dd:c25:c25a:d00a:7814
222c19:dd:d9:dd:c25:c25a:d00a:7815/1282c19:dd:d9:dd:c25:c25a:d00a:7815
232c19:dd:d9:dd:c25:c25a:d00a:7816/1282c19:dd:d9:dd:c25:c25a:d00a:7816
242c19:dd:d9:dd:c25:c25a:d00a:7817/1282c19:dd:d9:dd:c25:c25a:d00a:7817
252c19:dd:d9:dd:c25:c25a:d00a:7818/1282c19:dd:d9:dd:c25:c25a:d00a:7818
262c19:dd:d9:dd:c25:c25a:d00a:7819/1282c19:dd:d9:dd:c25:c25a:d00a:7819
272c19:dd:d9:dd:c25:c25a:d00a:781a/1282c19:dd:d9:dd:c25:c25a:d00a:781a
282c19:dd:d9:dd:c25:c25a:d00a:781b/1282c19:dd:d9:dd:c25:c25a:d00a:781b
292c19:dd:d9:dd:c25:c25a:d00a:781c/1282c19:dd:d9:dd:c25:c25a:d00a:781c
302c19:dd:d9:dd:c25:c25a:d00a:781d/1282c19:dd:d9:dd:c25:c25a:d00a:781d
312c19:dd:d9:dd:c25:c25a:d00a:781e/1282c19:dd:d9:dd:c25:c25a:d00a:781e
322c19:dd:d9:dd:c25:c25a:d00a:781f/1282c19:dd:d9:dd:c25:c25a:d00a:781f
332c19:dd:d9:dd:c25:c25a:d00a:7820/1282c19:dd:d9:dd:c25:c25a:d00a:7820
342c19:dd:d9:dd:c25:c25a:d00a:7821/1282c19:dd:d9:dd:c25:c25a:d00a:7821
352c19:dd:d9:dd:c25:c25a:d00a:7822/1282c19:dd:d9:dd:c25:c25a:d00a:7822
362c19:dd:d9:dd:c25:c25a:d00a:7823/1282c19:dd:d9:dd:c25:c25a:d00a:7823
372c19:dd:d9:dd:c25:c25a:d00a:7824/1282c19:dd:d9:dd:c25:c25a:d00a:7824
382c19:dd:d9:dd:c25:c25a:d00a:7825/1282c19:dd:d9:dd:c25:c25a:d00a:7825
392c19:dd:d9:dd:c25:c25a:d00a:7826/1282c19:dd:d9:dd:c25:c25a:d00a:7826
402c19:dd:d9:dd:c25:c25a:d00a:7827/1282c19:dd:d9:dd:c25:c25a:d00a:7827
412c19:dd:d9:dd:c25:c25a:d00a:7828/1282c19:dd:d9:dd:c25:c25a:d00a:7828
422c19:dd:d9:dd:c25:c25a:d00a:7829/1282c19:dd:d9:dd:c25:c25a:d00a:7829
432c19:dd:d9:dd:c25:c25a:d00a:782a/1282c19:dd:d9:dd:c25:c25a:d00a:782a
442c19:dd:d9:dd:c25:c25a:d00a:782b/1282c19:dd:d9:dd:c25:c25a:d00a:782b
452c19:dd:d9:dd:c25:c25a:d00a:782c/1282c19:dd:d9:dd:c25:c25a:d00a:782c
462c19:dd:d9:dd:c25:c25a:d00a:782d/1282c19:dd:d9:dd:c25:c25a:d00a:782d
472c19:dd:d9:dd:c25:c25a:d00a:782e/1282c19:dd:d9:dd:c25:c25a:d00a:782e
482c19:dd:d9:dd:c25:c25a:d00a:782f/1282c19:dd:d9:dd:c25:c25a:d00a:782f
492c19:dd:d9:dd:c25:c25a:d00a:7830/1282c19:dd:d9:dd:c25:c25a:d00a:7830
502c19:dd:d9:dd:c25:c25a:d00a:7831/1282c19:dd:d9:dd:c25:c25a:d00a:7831
512c19:dd:d9:dd:c25:c25a:d00a:7832/1282c19:dd:d9:dd:c25:c25a:d00a:7832
522c19:dd:d9:dd:c25:c25a:d00a:7833/1282c19:dd:d9:dd:c25:c25a:d00a:7833
532c19:dd:d9:dd:c25:c25a:d00a:7834/1282c19:dd:d9:dd:c25:c25a:d00a:7834
542c19:dd:d9:dd:c25:c25a:d00a:7835/1282c19:dd:d9:dd:c25:c25a:d00a:7835
552c19:dd:d9:dd:c25:c25a:d00a:7836/1282c19:dd:d9:dd:c25:c25a:d00a:7836
562c19:dd:d9:dd:c25:c25a:d00a:7837/1282c19:dd:d9:dd:c25:c25a:d00a:7837
572c19:dd:d9:dd:c25:c25a:d00a:7838/1282c19:dd:d9:dd:c25:c25a:d00a:7838
582c19:dd:d9:dd:c25:c25a:d00a:7839/1282c19:dd:d9:dd:c25:c25a:d00a:7839
592c19:dd:d9:dd:c25:c25a:d00a:783a/1282c19:dd:d9:dd:c25:c25a:d00a:783a
602c19:dd:d9:dd:c25:c25a:d00a:783b/1282c19:dd:d9:dd:c25:c25a:d00a:783b
612c19:dd:d9:dd:c25:c25a:d00a:783c/1282c19:dd:d9:dd:c25:c25a:d00a:783c
622c19:dd:d9:dd:c25:c25a:d00a:783d/1282c19:dd:d9:dd:c25:c25a:d00a:783d
632c19:dd:d9:dd:c25:c25a:d00a:783e/1282c19:dd:d9:dd:c25:c25a:d00a:783e
642c19:dd:d9:dd:c25:c25a:d00a:783f/1282c19:dd:d9:dd:c25:c25a:d00a:783f
652c19:dd:d9:dd:c25:c25a:d00a:7840/1282c19:dd:d9:dd:c25:c25a:d00a:7840
662c19:dd:d9:dd:c25:c25a:d00a:7841/1282c19:dd:d9:dd:c25:c25a:d00a:7841
672c19:dd:d9:dd:c25:c25a:d00a:7842/1282c19:dd:d9:dd:c25:c25a:d00a:7842
682c19:dd:d9:dd:c25:c25a:d00a:7843/1282c19:dd:d9:dd:c25:c25a:d00a:7843
692c19:dd:d9:dd:c25:c25a:d00a:7844/1282c19:dd:d9:dd:c25:c25a:d00a:7844
702c19:dd:d9:dd:c25:c25a:d00a:7845/1282c19:dd:d9:dd:c25:c25a:d00a:7845
712c19:dd:d9:dd:c25:c25a:d00a:7846/1282c19:dd:d9:dd:c25:c25a:d00a:7846
722c19:dd:d9:dd:c25:c25a:d00a:7847/1282c19:dd:d9:dd:c25:c25a:d00a:7847
732c19:dd:d9:dd:c25:c25a:d00a:7848/1282c19:dd:d9:dd:c25:c25a:d00a:7848
742c19:dd:d9:dd:c25:c25a:d00a:7849/1282c19:dd:d9:dd:c25:c25a:d00a:7849
752c19:dd:d9:dd:c25:c25a:d00a:784a/1282c19:dd:d9:dd:c25:c25a:d00a:784a
762c19:dd:d9:dd:c25:c25a:d00a:784b/1282c19:dd:d9:dd:c25:c25a:d00a:784b
772c19:dd:d9:dd:c25:c25a:d00a:784c/1282c19:dd:d9:dd:c25:c25a:d00a:784c
782c19:dd:d9:dd:c25:c25a:d00a:784d/1282c19:dd:d9:dd:c25:c25a:d00a:784d
792c19:dd:d9:dd:c25:c25a:d00a:784e/1282c19:dd:d9:dd:c25:c25a:d00a:784e
802c19:dd:d9:dd:c25:c25a:d00a:784f/1282c19:dd:d9:dd:c25:c25a:d00a:784f
812c19:dd:d9:dd:c25:c25a:d00a:7850/1282c19:dd:d9:dd:c25:c25a:d00a:7850
822c19:dd:d9:dd:c25:c25a:d00a:7851/1282c19:dd:d9:dd:c25:c25a:d00a:7851
832c19:dd:d9:dd:c25:c25a:d00a:7852/1282c19:dd:d9:dd:c25:c25a:d00a:7852
842c19:dd:d9:dd:c25:c25a:d00a:7853/1282c19:dd:d9:dd:c25:c25a:d00a:7853
852c19:dd:d9:dd:c25:c25a:d00a:7854/1282c19:dd:d9:dd:c25:c25a:d00a:7854
862c19:dd:d9:dd:c25:c25a:d00a:7855/1282c19:dd:d9:dd:c25:c25a:d00a:7855
872c19:dd:d9:dd:c25:c25a:d00a:7856/1282c19:dd:d9:dd:c25:c25a:d00a:7856
882c19:dd:d9:dd:c25:c25a:d00a:7857/1282c19:dd:d9:dd:c25:c25a:d00a:7857
892c19:dd:d9:dd:c25:c25a:d00a:7858/1282c19:dd:d9:dd:c25:c25a:d00a:7858
902c19:dd:d9:dd:c25:c25a:d00a:7859/1282c19:dd:d9:dd:c25:c25a:d00a:7859
912c19:dd:d9:dd:c25:c25a:d00a:785a/1282c19:dd:d9:dd:c25:c25a:d00a:785a
922c19:dd:d9:dd:c25:c25a:d00a:785b/1282c19:dd:d9:dd:c25:c25a:d00a:785b
932c19:dd:d9:dd:c25:c25a:d00a:785c/1282c19:dd:d9:dd:c25:c25a:d00a:785c
942c19:dd:d9:dd:c25:c25a:d00a:785d/1282c19:dd:d9:dd:c25:c25a:d00a:785d
952c19:dd:d9:dd:c25:c25a:d00a:785e/1282c19:dd:d9:dd:c25:c25a:d00a:785e
962c19:dd:d9:dd:c25:c25a:d00a:785f/1282c19:dd:d9:dd:c25:c25a:d00a:785f
972c19:dd:d9:dd:c25:c25a:d00a:7860/1282c19:dd:d9:dd:c25:c25a:d00a:7860
982c19:dd:d9:dd:c25:c25a:d00a:7861/1282c19:dd:d9:dd:c25:c25a:d00a:7861
992c19:dd:d9:dd:c25:c25a:d00a:7862/1282c19:dd:d9:dd:c25:c25a:d00a:7862
1002c19:dd:d9:dd:c25:c25a:d00a:7863/1282c19:dd:d9:dd:c25:c25a:d00a:7863
1012c19:dd:d9:dd:c25:c25a:d00a:7864/1282c19:dd:d9:dd:c25:c25a:d00a:7864
1022c19:dd:d9:dd:c25:c25a:d00a:7865/1282c19:dd:d9:dd:c25:c25a:d00a:7865
1032c19:dd:d9:dd:c25:c25a:d00a:7866/1282c19:dd:d9:dd:c25:c25a:d00a:7866
1042c19:dd:d9:dd:c25:c25a:d00a:7867/1282c19:dd:d9:dd:c25:c25a:d00a:7867
1052c19:dd:d9:dd:c25:c25a:d00a:7868/1282c19:dd:d9:dd:c25:c25a:d00a:7868
1062c19:dd:d9:dd:c25:c25a:d00a:7869/1282c19:dd:d9:dd:c25:c25a:d00a:7869
1072c19:dd:d9:dd:c25:c25a:d00a:786a/1282c19:dd:d9:dd:c25:c25a:d00a:786a
1082c19:dd:d9:dd:c25:c25a:d00a:786b/1282c19:dd:d9:dd:c25:c25a:d00a:786b
1092c19:dd:d9:dd:c25:c25a:d00a:786c/1282c19:dd:d9:dd:c25:c25a:d00a:786c
1102c19:dd:d9:dd:c25:c25a:d00a:786d/1282c19:dd:d9:dd:c25:c25a:d00a:786d
1112c19:dd:d9:dd:c25:c25a:d00a:786e/1282c19:dd:d9:dd:c25:c25a:d00a:786e
1122c19:dd:d9:dd:c25:c25a:d00a:786f/1282c19:dd:d9:dd:c25:c25a:d00a:786f
1132c19:dd:d9:dd:c25:c25a:d00a:7870/1282c19:dd:d9:dd:c25:c25a:d00a:7870
1142c19:dd:d9:dd:c25:c25a:d00a:7871/1282c19:dd:d9:dd:c25:c25a:d00a:7871
1152c19:dd:d9:dd:c25:c25a:d00a:7872/1282c19:dd:d9:dd:c25:c25a:d00a:7872
1162c19:dd:d9:dd:c25:c25a:d00a:7873/1282c19:dd:d9:dd:c25:c25a:d00a:7873
1172c19:dd:d9:dd:c25:c25a:d00a:7874/1282c19:dd:d9:dd:c25:c25a:d00a:7874
1182c19:dd:d9:dd:c25:c25a:d00a:7875/1282c19:dd:d9:dd:c25:c25a:d00a:7875
1192c19:dd:d9:dd:c25:c25a:d00a:7876/1282c19:dd:d9:dd:c25:c25a:d00a:7876
1202c19:dd:d9:dd:c25:c25a:d00a:7877/1282c19:dd:d9:dd:c25:c25a:d00a:7877
1212c19:dd:d9:dd:c25:c25a:d00a:7878/1282c19:dd:d9:dd:c25:c25a:d00a:7878
1222c19:dd:d9:dd:c25:c25a:d00a:7879/1282c19:dd:d9:dd:c25:c25a:d00a:7879
1232c19:dd:d9:dd:c25:c25a:d00a:787a/1282c19:dd:d9:dd:c25:c25a:d00a:787a
1242c19:dd:d9:dd:c25:c25a:d00a:787b/1282c19:dd:d9:dd:c25:c25a:d00a:787b
1252c19:dd:d9:dd:c25:c25a:d00a:787c/1282c19:dd:d9:dd:c25:c25a:d00a:787c
1262c19:dd:d9:dd:c25:c25a:d00a:787d/1282c19:dd:d9:dd:c25:c25a:d00a:787d
1272c19:dd:d9:dd:c25:c25a:d00a:787e/1282c19:dd:d9:dd:c25:c25a:d00a:787e
1282c19:dd:d9:dd:c25:c25a:d00a:787f/1282c19:dd:d9:dd:c25:c25a:d00a:787f
1292c19:dd:d9:dd:c25:c25a:d00a:7880/1282c19:dd:d9:dd:c25:c25a:d00a:7880
1302c19:dd:d9:dd:c25:c25a:d00a:7881/1282c19:dd:d9:dd:c25:c25a:d00a:7881
1312c19:dd:d9:dd:c25:c25a:d00a:7882/1282c19:dd:d9:dd:c25:c25a:d00a:7882
1322c19:dd:d9:dd:c25:c25a:d00a:7883/1282c19:dd:d9:dd:c25:c25a:d00a:7883
1332c19:dd:d9:dd:c25:c25a:d00a:7884/1282c19:dd:d9:dd:c25:c25a:d00a:7884
1342c19:dd:d9:dd:c25:c25a:d00a:7885/1282c19:dd:d9:dd:c25:c25a:d00a:7885
1352c19:dd:d9:dd:c25:c25a:d00a:7886/1282c19:dd:d9:dd:c25:c25a:d00a:7886
1362c19:dd:d9:dd:c25:c25a:d00a:7887/1282c19:dd:d9:dd:c25:c25a:d00a:7887
1372c19:dd:d9:dd:c25:c25a:d00a:7888/1282c19:dd:d9:dd:c25:c25a:d00a:7888
1382c19:dd:d9:dd:c25:c25a:d00a:7889/1282c19:dd:d9:dd:c25:c25a:d00a:7889
1392c19:dd:d9:dd:c25:c25a:d00a:788a/1282c19:dd:d9:dd:c25:c25a:d00a:788a
1402c19:dd:d9:dd:c25:c25a:d00a:788b/1282c19:dd:d9:dd:c25:c25a:d00a:788b
1412c19:dd:d9:dd:c25:c25a:d00a:788c/1282c19:dd:d9:dd:c25:c25a:d00a:788c
1422c19:dd:d9:dd:c25:c25a:d00a:788d/1282c19:dd:d9:dd:c25:c25a:d00a:788d
1432c19:dd:d9:dd:c25:c25a:d00a:788e/1282c19:dd:d9:dd:c25:c25a:d00a:788e
1442c19:dd:d9:dd:c25:c25a:d00a:788f/1282c19:dd:d9:dd:c25:c25a:d00a:788f
1452c19:dd:d9:dd:c25:c25a:d00a:7890/1282c19:dd:d9:dd:c25:c25a:d00a:7890
1462c19:dd:d9:dd:c25:c25a:d00a:7891/1282c19:dd:d9:dd:c25:c25a:d00a:7891
1472c19:dd:d9:dd:c25:c25a:d00a:7892/1282c19:dd:d9:dd:c25:c25a:d00a:7892
1482c19:dd:d9:dd:c25:c25a:d00a:7893/1282c19:dd:d9:dd:c25:c25a:d00a:7893
1492c19:dd:d9:dd:c25:c25a:d00a:7894/1282c19:dd:d9:dd:c25:c25a:d00a:7894
1502c19:dd:d9:dd:c25:c25a:d00a:7895/1282c19:dd:d9:dd:c25:c25a:d00a:7895
1512c19:dd:d9:dd:c25:c25a:d00a:7896/1282c19:dd:d9:dd:c25:c25a:d00a:7896
1522c19:dd:d9:dd:c25:c25a:d00a:7897/1282c19:dd:d9:dd:c25:c25a:d00a:7897
1532c19:dd:d9:dd:c25:c25a:d00a:7898/1282c19:dd:d9:dd:c25:c25a:d00a:7898
1542c19:dd:d9:dd:c25:c25a:d00a:7899/1282c19:dd:d9:dd:c25:c25a:d00a:7899
1552c19:dd:d9:dd:c25:c25a:d00a:789a/1282c19:dd:d9:dd:c25:c25a:d00a:789a
1562c19:dd:d9:dd:c25:c25a:d00a:789b/1282c19:dd:d9:dd:c25:c25a:d00a:789b
1572c19:dd:d9:dd:c25:c25a:d00a:789c/1282c19:dd:d9:dd:c25:c25a:d00a:789c
1582c19:dd:d9:dd:c25:c25a:d00a:789d/1282c19:dd:d9:dd:c25:c25a:d00a:789d
1592c19:dd:d9:dd:c25:c25a:d00a:789e/1282c19:dd:d9:dd:c25:c25a:d00a:789e
1602c19:dd:d9:dd:c25:c25a:d00a:789f/1282c19:dd:d9:dd:c25:c25a:d00a:789f
1612c19:dd:d9:dd:c25:c25a:d00a:78a0/1282c19:dd:d9:dd:c25:c25a:d00a:78a0
1622c19:dd:d9:dd:c25:c25a:d00a:78a1/1282c19:dd:d9:dd:c25:c25a:d00a:78a1
1632c19:dd:d9:dd:c25:c25a:d00a:78a2/1282c19:dd:d9:dd:c25:c25a:d00a:78a2
1642c19:dd:d9:dd:c25:c25a:d00a:78a3/1282c19:dd:d9:dd:c25:c25a:d00a:78a3
1652c19:dd:d9:dd:c25:c25a:d00a:78a4/1282c19:dd:d9:dd:c25:c25a:d00a:78a4
1662c19:dd:d9:dd:c25:c25a:d00a:78a5/1282c19:dd:d9:dd:c25:c25a:d00a:78a5
1672c19:dd:d9:dd:c25:c25a:d00a:78a6/1282c19:dd:d9:dd:c25:c25a:d00a:78a6
1682c19:dd:d9:dd:c25:c25a:d00a:78a7/1282c19:dd:d9:dd:c25:c25a:d00a:78a7
1692c19:dd:d9:dd:c25:c25a:d00a:78a8/1282c19:dd:d9:dd:c25:c25a:d00a:78a8
1702c19:dd:d9:dd:c25:c25a:d00a:78a9/1282c19:dd:d9:dd:c25:c25a:d00a:78a9
1712c19:dd:d9:dd:c25:c25a:d00a:78aa/1282c19:dd:d9:dd:c25:c25a:d00a:78aa
1722c19:dd:d9:dd:c25:c25a:d00a:78ab/1282c19:dd:d9:dd:c25:c25a:d00a:78ab
1732c19:dd:d9:dd:c25:c25a:d00a:78ac/1282c19:dd:d9:dd:c25:c25a:d00a:78ac
1742c19:dd:d9:dd:c25:c25a:d00a:78ad/1282c19:dd:d9:dd:c25:c25a:d00a:78ad
1752c19:dd:d9:dd:c25:c25a:d00a:78ae/1282c19:dd:d9:dd:c25:c25a:d00a:78ae
1762c19:dd:d9:dd:c25:c25a:d00a:78af/1282c19:dd:d9:dd:c25:c25a:d00a:78af
1772c19:dd:d9:dd:c25:c25a:d00a:78b0/1282c19:dd:d9:dd:c25:c25a:d00a:78b0
1782c19:dd:d9:dd:c25:c25a:d00a:78b1/1282c19:dd:d9:dd:c25:c25a:d00a:78b1
1792c19:dd:d9:dd:c25:c25a:d00a:78b2/1282c19:dd:d9:dd:c25:c25a:d00a:78b2
1802c19:dd:d9:dd:c25:c25a:d00a:78b3/1282c19:dd:d9:dd:c25:c25a:d00a:78b3
1812c19:dd:d9:dd:c25:c25a:d00a:78b4/1282c19:dd:d9:dd:c25:c25a:d00a:78b4
1822c19:dd:d9:dd:c25:c25a:d00a:78b5/1282c19:dd:d9:dd:c25:c25a:d00a:78b5
1832c19:dd:d9:dd:c25:c25a:d00a:78b6/1282c19:dd:d9:dd:c25:c25a:d00a:78b6
1842c19:dd:d9:dd:c25:c25a:d00a:78b7/1282c19:dd:d9:dd:c25:c25a:d00a:78b7
1852c19:dd:d9:dd:c25:c25a:d00a:78b8/1282c19:dd:d9:dd:c25:c25a:d00a:78b8
1862c19:dd:d9:dd:c25:c25a:d00a:78b9/1282c19:dd:d9:dd:c25:c25a:d00a:78b9
1872c19:dd:d9:dd:c25:c25a:d00a:78ba/1282c19:dd:d9:dd:c25:c25a:d00a:78ba
1882c19:dd:d9:dd:c25:c25a:d00a:78bb/1282c19:dd:d9:dd:c25:c25a:d00a:78bb
1892c19:dd:d9:dd:c25:c25a:d00a:78bc/1282c19:dd:d9:dd:c25:c25a:d00a:78bc
1902c19:dd:d9:dd:c25:c25a:d00a:78bd/1282c19:dd:d9:dd:c25:c25a:d00a:78bd
1912c19:dd:d9:dd:c25:c25a:d00a:78be/1282c19:dd:d9:dd:c25:c25a:d00a:78be
1922c19:dd:d9:dd:c25:c25a:d00a:78bf/1282c19:dd:d9:dd:c25:c25a:d00a:78bf
1932c19:dd:d9:dd:c25:c25a:d00a:78c0/1282c19:dd:d9:dd:c25:c25a:d00a:78c0
1942c19:dd:d9:dd:c25:c25a:d00a:78c1/1282c19:dd:d9:dd:c25:c25a:d00a:78c1
1952c19:dd:d9:dd:c25:c25a:d00a:78c2/1282c19:dd:d9:dd:c25:c25a:d00a:78c2
1962c19:dd:d9:dd:c25:c25a:d00a:78c3/1282c19:dd:d9:dd:c25:c25a:d00a:78c3
1972c19:dd:d9:dd:c25:c25a:d00a:78c4/1282c19:dd:d9:dd:c25:c25a:d00a:78c4
1982c19:dd:d9:dd:c25:c25a:d00a:78c5/1282c19:dd:d9:dd:c25:c25a:d00a:78c5
1992c19:dd:d9:dd:c25:c25a:d00a:78c6/1282c19:dd:d9:dd:c25:c25a:d00a:78c6
2002c19:dd:d9:dd:c25:c25a:d00a:78c7/1282c19:dd:d9:dd:c25:c25a:d00a:78c7
2012c19:dd:d9:dd:c25:c25a:d00a:78c8/1282c19:dd:d9:dd:c25:c25a:d00a:78c8
2022c19:dd:d9:dd:c25:c25a:d00a:78c9/1282c19:dd:d9:dd:c25:c25a:d00a:78c9
2032c19:dd:d9:dd:c25:c25a:d00a:78ca/1282c19:dd:d9:dd:c25:c25a:d00a:78ca
2042c19:dd:d9:dd:c25:c25a:d00a:78cb/1282c19:dd:d9:dd:c25:c25a:d00a:78cb
2052c19:dd:d9:dd:c25:c25a:d00a:78cc/1282c19:dd:d9:dd:c25:c25a:d00a:78cc
2062c19:dd:d9:dd:c25:c25a:d00a:78cd/1282c19:dd:d9:dd:c25:c25a:d00a:78cd
2072c19:dd:d9:dd:c25:c25a:d00a:78ce/1282c19:dd:d9:dd:c25:c25a:d00a:78ce
2082c19:dd:d9:dd:c25:c25a:d00a:78cf/1282c19:dd:d9:dd:c25:c25a:d00a:78cf
2092c19:dd:d9:dd:c25:c25a:d00a:78d0/1282c19:dd:d9:dd:c25:c25a:d00a:78d0
2102c19:dd:d9:dd:c25:c25a:d00a:78d1/1282c19:dd:d9:dd:c25:c25a:d00a:78d1
2112c19:dd:d9:dd:c25:c25a:d00a:78d2/1282c19:dd:d9:dd:c25:c25a:d00a:78d2
2122c19:dd:d9:dd:c25:c25a:d00a:78d3/1282c19:dd:d9:dd:c25:c25a:d00a:78d3
2132c19:dd:d9:dd:c25:c25a:d00a:78d4/1282c19:dd:d9:dd:c25:c25a:d00a:78d4
2142c19:dd:d9:dd:c25:c25a:d00a:78d5/1282c19:dd:d9:dd:c25:c25a:d00a:78d5
2152c19:dd:d9:dd:c25:c25a:d00a:78d6/1282c19:dd:d9:dd:c25:c25a:d00a:78d6
2162c19:dd:d9:dd:c25:c25a:d00a:78d7/1282c19:dd:d9:dd:c25:c25a:d00a:78d7
2172c19:dd:d9:dd:c25:c25a:d00a:78d8/1282c19:dd:d9:dd:c25:c25a:d00a:78d8
2182c19:dd:d9:dd:c25:c25a:d00a:78d9/1282c19:dd:d9:dd:c25:c25a:d00a:78d9
2192c19:dd:d9:dd:c25:c25a:d00a:78da/1282c19:dd:d9:dd:c25:c25a:d00a:78da
2202c19:dd:d9:dd:c25:c25a:d00a:78db/1282c19:dd:d9:dd:c25:c25a:d00a:78db
2212c19:dd:d9:dd:c25:c25a:d00a:78dc/1282c19:dd:d9:dd:c25:c25a:d00a:78dc
2222c19:dd:d9:dd:c25:c25a:d00a:78dd/1282c19:dd:d9:dd:c25:c25a:d00a:78dd
2232c19:dd:d9:dd:c25:c25a:d00a:78de/1282c19:dd:d9:dd:c25:c25a:d00a:78de
2242c19:dd:d9:dd:c25:c25a:d00a:78df/1282c19:dd:d9:dd:c25:c25a:d00a:78df
2252c19:dd:d9:dd:c25:c25a:d00a:78e0/1282c19:dd:d9:dd:c25:c25a:d00a:78e0
2262c19:dd:d9:dd:c25:c25a:d00a:78e1/1282c19:dd:d9:dd:c25:c25a:d00a:78e1
2272c19:dd:d9:dd:c25:c25a:d00a:78e2/1282c19:dd:d9:dd:c25:c25a:d00a:78e2
2282c19:dd:d9:dd:c25:c25a:d00a:78e3/1282c19:dd:d9:dd:c25:c25a:d00a:78e3
2292c19:dd:d9:dd:c25:c25a:d00a:78e4/1282c19:dd:d9:dd:c25:c25a:d00a:78e4
2302c19:dd:d9:dd:c25:c25a:d00a:78e5/1282c19:dd:d9:dd:c25:c25a:d00a:78e5
2312c19:dd:d9:dd:c25:c25a:d00a:78e6/1282c19:dd:d9:dd:c25:c25a:d00a:78e6
2322c19:dd:d9:dd:c25:c25a:d00a:78e7/1282c19:dd:d9:dd:c25:c25a:d00a:78e7
2332c19:dd:d9:dd:c25:c25a:d00a:78e8/1282c19:dd:d9:dd:c25:c25a:d00a:78e8
2342c19:dd:d9:dd:c25:c25a:d00a:78e9/1282c19:dd:d9:dd:c25:c25a:d00a:78e9
2352c19:dd:d9:dd:c25:c25a:d00a:78ea/1282c19:dd:d9:dd:c25:c25a:d00a:78ea
2362c19:dd:d9:dd:c25:c25a:d00a:78eb/1282c19:dd:d9:dd:c25:c25a:d00a:78eb
2372c19:dd:d9:dd:c25:c25a:d00a:78ec/1282c19:dd:d9:dd:c25:c25a:d00a:78ec
2382c19:dd:d9:dd:c25:c25a:d00a:78ed/1282c19:dd:d9:dd:c25:c25a:d00a:78ed
2392c19:dd:d9:dd:c25:c25a:d00a:78ee/1282c19:dd:d9:dd:c25:c25a:d00a:78ee
2402c19:dd:d9:dd:c25:c25a:d00a:78ef/1282c19:dd:d9:dd:c25:c25a:d00a:78ef
2412c19:dd:d9:dd:c25:c25a:d00a:78f0/1282c19:dd:d9:dd:c25:c25a:d00a:78f0
2422c19:dd:d9:dd:c25:c25a:d00a:78f1/1282c19:dd:d9:dd:c25:c25a:d00a:78f1
2432c19:dd:d9:dd:c25:c25a:d00a:78f2/1282c19:dd:d9:dd:c25:c25a:d00a:78f2
2442c19:dd:d9:dd:c25:c25a:d00a:78f3/1282c19:dd:d9:dd:c25:c25a:d00a:78f3
2452c19:dd:d9:dd:c25:c25a:d00a:78f4/1282c19:dd:d9:dd:c25:c25a:d00a:78f4
2462c19:dd:d9:dd:c25:c25a:d00a:78f5/1282c19:dd:d9:dd:c25:c25a:d00a:78f5
2472c19:dd:d9:dd:c25:c25a:d00a:78f6/1282c19:dd:d9:dd:c25:c25a:d00a:78f6
2482c19:dd:d9:dd:c25:c25a:d00a:78f7/1282c19:dd:d9:dd:c25:c25a:d00a:78f7
2492c19:dd:d9:dd:c25:c25a:d00a:78f8/1282c19:dd:d9:dd:c25:c25a:d00a:78f8
2502c19:dd:d9:dd:c25:c25a:d00a:78f9/1282c19:dd:d9:dd:c25:c25a:d00a:78f9
2512c19:dd:d9:dd:c25:c25a:d00a:78fa/1282c19:dd:d9:dd:c25:c25a:d00a:78fa
2522c19:dd:d9:dd:c25:c25a:d00a:78fb/1282c19:dd:d9:dd:c25:c25a:d00a:78fb
2532c19:dd:d9:dd:c25:c25a:d00a:78fc/1282c19:dd:d9:dd:c25:c25a:d00a:78fc
2542c19:dd:d9:dd:c25:c25a:d00a:78fd/1282c19:dd:d9:dd:c25:c25a:d00a:78fd
2552c19:dd:d9:dd:c25:c25a:d00a:78fe/1282c19:dd:d9:dd:c25:c25a:d00a:78fe
2562c19:dd:d9:dd:c25:c25a:d00a:78ff/1282c19:dd:d9:dd:c25:c25a:d00a:78ff

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.