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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/117
Addresses2,048
/64 networksPart of one
Network
2c19:dd:c25:c25d:dd:dd:dd:800/117
First address
2c19:dd:c25:c25d:dd:dd:dd:800
Last address
2c19:dd:c25:c25d:dd:dd:dd:fff
Addresses
2,048
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:0800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
8.0.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
9.0.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
a.0.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
b.0.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
c.0.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
d.0.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
e.0.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
f.0.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
/117 is not on a 4-bit boundary, so it takes 8 /120 zones.
Split into smaller subnets/128
/118 (2)/119 (4)/120 (8)/121 (16)/124 (128)/127 (1,024)/128 (2,048)

2c19:dd:c25:c25d:dd:dd:dd:800/117 makes 2,048 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:800/1282c19:dd:c25:c25d:dd:dd:dd:800
22c19:dd:c25:c25d:dd:dd:dd:801/1282c19:dd:c25:c25d:dd:dd:dd:801
32c19:dd:c25:c25d:dd:dd:dd:802/1282c19:dd:c25:c25d:dd:dd:dd:802
42c19:dd:c25:c25d:dd:dd:dd:803/1282c19:dd:c25:c25d:dd:dd:dd:803
52c19:dd:c25:c25d:dd:dd:dd:804/1282c19:dd:c25:c25d:dd:dd:dd:804
62c19:dd:c25:c25d:dd:dd:dd:805/1282c19:dd:c25:c25d:dd:dd:dd:805
72c19:dd:c25:c25d:dd:dd:dd:806/1282c19:dd:c25:c25d:dd:dd:dd:806
82c19:dd:c25:c25d:dd:dd:dd:807/1282c19:dd:c25:c25d:dd:dd:dd:807
92c19:dd:c25:c25d:dd:dd:dd:808/1282c19:dd:c25:c25d:dd:dd:dd:808
102c19:dd:c25:c25d:dd:dd:dd:809/1282c19:dd:c25:c25d:dd:dd:dd:809
112c19:dd:c25:c25d:dd:dd:dd:80a/1282c19:dd:c25:c25d:dd:dd:dd:80a
122c19:dd:c25:c25d:dd:dd:dd:80b/1282c19:dd:c25:c25d:dd:dd:dd:80b
132c19:dd:c25:c25d:dd:dd:dd:80c/1282c19:dd:c25:c25d:dd:dd:dd:80c
142c19:dd:c25:c25d:dd:dd:dd:80d/1282c19:dd:c25:c25d:dd:dd:dd:80d
152c19:dd:c25:c25d:dd:dd:dd:80e/1282c19:dd:c25:c25d:dd:dd:dd:80e
162c19:dd:c25:c25d:dd:dd:dd:80f/1282c19:dd:c25:c25d:dd:dd:dd:80f
172c19:dd:c25:c25d:dd:dd:dd:810/1282c19:dd:c25:c25d:dd:dd:dd:810
182c19:dd:c25:c25d:dd:dd:dd:811/1282c19:dd:c25:c25d:dd:dd:dd:811
192c19:dd:c25:c25d:dd:dd:dd:812/1282c19:dd:c25:c25d:dd:dd:dd:812
202c19:dd:c25:c25d:dd:dd:dd:813/1282c19:dd:c25:c25d:dd:dd:dd:813
212c19:dd:c25:c25d:dd:dd:dd:814/1282c19:dd:c25:c25d:dd:dd:dd:814
222c19:dd:c25:c25d:dd:dd:dd:815/1282c19:dd:c25:c25d:dd:dd:dd:815
232c19:dd:c25:c25d:dd:dd:dd:816/1282c19:dd:c25:c25d:dd:dd:dd:816
242c19:dd:c25:c25d:dd:dd:dd:817/1282c19:dd:c25:c25d:dd:dd:dd:817
252c19:dd:c25:c25d:dd:dd:dd:818/1282c19:dd:c25:c25d:dd:dd:dd:818
262c19:dd:c25:c25d:dd:dd:dd:819/1282c19:dd:c25:c25d:dd:dd:dd:819
272c19:dd:c25:c25d:dd:dd:dd:81a/1282c19:dd:c25:c25d:dd:dd:dd:81a
282c19:dd:c25:c25d:dd:dd:dd:81b/1282c19:dd:c25:c25d:dd:dd:dd:81b
292c19:dd:c25:c25d:dd:dd:dd:81c/1282c19:dd:c25:c25d:dd:dd:dd:81c
302c19:dd:c25:c25d:dd:dd:dd:81d/1282c19:dd:c25:c25d:dd:dd:dd:81d
312c19:dd:c25:c25d:dd:dd:dd:81e/1282c19:dd:c25:c25d:dd:dd:dd:81e
322c19:dd:c25:c25d:dd:dd:dd:81f/1282c19:dd:c25:c25d:dd:dd:dd:81f
332c19:dd:c25:c25d:dd:dd:dd:820/1282c19:dd:c25:c25d:dd:dd:dd:820
342c19:dd:c25:c25d:dd:dd:dd:821/1282c19:dd:c25:c25d:dd:dd:dd:821
352c19:dd:c25:c25d:dd:dd:dd:822/1282c19:dd:c25:c25d:dd:dd:dd:822
362c19:dd:c25:c25d:dd:dd:dd:823/1282c19:dd:c25:c25d:dd:dd:dd:823
372c19:dd:c25:c25d:dd:dd:dd:824/1282c19:dd:c25:c25d:dd:dd:dd:824
382c19:dd:c25:c25d:dd:dd:dd:825/1282c19:dd:c25:c25d:dd:dd:dd:825
392c19:dd:c25:c25d:dd:dd:dd:826/1282c19:dd:c25:c25d:dd:dd:dd:826
402c19:dd:c25:c25d:dd:dd:dd:827/1282c19:dd:c25:c25d:dd:dd:dd:827
412c19:dd:c25:c25d:dd:dd:dd:828/1282c19:dd:c25:c25d:dd:dd:dd:828
422c19:dd:c25:c25d:dd:dd:dd:829/1282c19:dd:c25:c25d:dd:dd:dd:829
432c19:dd:c25:c25d:dd:dd:dd:82a/1282c19:dd:c25:c25d:dd:dd:dd:82a
442c19:dd:c25:c25d:dd:dd:dd:82b/1282c19:dd:c25:c25d:dd:dd:dd:82b
452c19:dd:c25:c25d:dd:dd:dd:82c/1282c19:dd:c25:c25d:dd:dd:dd:82c
462c19:dd:c25:c25d:dd:dd:dd:82d/1282c19:dd:c25:c25d:dd:dd:dd:82d
472c19:dd:c25:c25d:dd:dd:dd:82e/1282c19:dd:c25:c25d:dd:dd:dd:82e
482c19:dd:c25:c25d:dd:dd:dd:82f/1282c19:dd:c25:c25d:dd:dd:dd:82f
492c19:dd:c25:c25d:dd:dd:dd:830/1282c19:dd:c25:c25d:dd:dd:dd:830
502c19:dd:c25:c25d:dd:dd:dd:831/1282c19:dd:c25:c25d:dd:dd:dd:831
512c19:dd:c25:c25d:dd:dd:dd:832/1282c19:dd:c25:c25d:dd:dd:dd:832
522c19:dd:c25:c25d:dd:dd:dd:833/1282c19:dd:c25:c25d:dd:dd:dd:833
532c19:dd:c25:c25d:dd:dd:dd:834/1282c19:dd:c25:c25d:dd:dd:dd:834
542c19:dd:c25:c25d:dd:dd:dd:835/1282c19:dd:c25:c25d:dd:dd:dd:835
552c19:dd:c25:c25d:dd:dd:dd:836/1282c19:dd:c25:c25d:dd:dd:dd:836
562c19:dd:c25:c25d:dd:dd:dd:837/1282c19:dd:c25:c25d:dd:dd:dd:837
572c19:dd:c25:c25d:dd:dd:dd:838/1282c19:dd:c25:c25d:dd:dd:dd:838
582c19:dd:c25:c25d:dd:dd:dd:839/1282c19:dd:c25:c25d:dd:dd:dd:839
592c19:dd:c25:c25d:dd:dd:dd:83a/1282c19:dd:c25:c25d:dd:dd:dd:83a
602c19:dd:c25:c25d:dd:dd:dd:83b/1282c19:dd:c25:c25d:dd:dd:dd:83b
612c19:dd:c25:c25d:dd:dd:dd:83c/1282c19:dd:c25:c25d:dd:dd:dd:83c
622c19:dd:c25:c25d:dd:dd:dd:83d/1282c19:dd:c25:c25d:dd:dd:dd:83d
632c19:dd:c25:c25d:dd:dd:dd:83e/1282c19:dd:c25:c25d:dd:dd:dd:83e
642c19:dd:c25:c25d:dd:dd:dd:83f/1282c19:dd:c25:c25d:dd:dd:dd:83f
652c19:dd:c25:c25d:dd:dd:dd:840/1282c19:dd:c25:c25d:dd:dd:dd:840
662c19:dd:c25:c25d:dd:dd:dd:841/1282c19:dd:c25:c25d:dd:dd:dd:841
672c19:dd:c25:c25d:dd:dd:dd:842/1282c19:dd:c25:c25d:dd:dd:dd:842
682c19:dd:c25:c25d:dd:dd:dd:843/1282c19:dd:c25:c25d:dd:dd:dd:843
692c19:dd:c25:c25d:dd:dd:dd:844/1282c19:dd:c25:c25d:dd:dd:dd:844
702c19:dd:c25:c25d:dd:dd:dd:845/1282c19:dd:c25:c25d:dd:dd:dd:845
712c19:dd:c25:c25d:dd:dd:dd:846/1282c19:dd:c25:c25d:dd:dd:dd:846
722c19:dd:c25:c25d:dd:dd:dd:847/1282c19:dd:c25:c25d:dd:dd:dd:847
732c19:dd:c25:c25d:dd:dd:dd:848/1282c19:dd:c25:c25d:dd:dd:dd:848
742c19:dd:c25:c25d:dd:dd:dd:849/1282c19:dd:c25:c25d:dd:dd:dd:849
752c19:dd:c25:c25d:dd:dd:dd:84a/1282c19:dd:c25:c25d:dd:dd:dd:84a
762c19:dd:c25:c25d:dd:dd:dd:84b/1282c19:dd:c25:c25d:dd:dd:dd:84b
772c19:dd:c25:c25d:dd:dd:dd:84c/1282c19:dd:c25:c25d:dd:dd:dd:84c
782c19:dd:c25:c25d:dd:dd:dd:84d/1282c19:dd:c25:c25d:dd:dd:dd:84d
792c19:dd:c25:c25d:dd:dd:dd:84e/1282c19:dd:c25:c25d:dd:dd:dd:84e
802c19:dd:c25:c25d:dd:dd:dd:84f/1282c19:dd:c25:c25d:dd:dd:dd:84f
812c19:dd:c25:c25d:dd:dd:dd:850/1282c19:dd:c25:c25d:dd:dd:dd:850
822c19:dd:c25:c25d:dd:dd:dd:851/1282c19:dd:c25:c25d:dd:dd:dd:851
832c19:dd:c25:c25d:dd:dd:dd:852/1282c19:dd:c25:c25d:dd:dd:dd:852
842c19:dd:c25:c25d:dd:dd:dd:853/1282c19:dd:c25:c25d:dd:dd:dd:853
852c19:dd:c25:c25d:dd:dd:dd:854/1282c19:dd:c25:c25d:dd:dd:dd:854
862c19:dd:c25:c25d:dd:dd:dd:855/1282c19:dd:c25:c25d:dd:dd:dd:855
872c19:dd:c25:c25d:dd:dd:dd:856/1282c19:dd:c25:c25d:dd:dd:dd:856
882c19:dd:c25:c25d:dd:dd:dd:857/1282c19:dd:c25:c25d:dd:dd:dd:857
892c19:dd:c25:c25d:dd:dd:dd:858/1282c19:dd:c25:c25d:dd:dd:dd:858
902c19:dd:c25:c25d:dd:dd:dd:859/1282c19:dd:c25:c25d:dd:dd:dd:859
912c19:dd:c25:c25d:dd:dd:dd:85a/1282c19:dd:c25:c25d:dd:dd:dd:85a
922c19:dd:c25:c25d:dd:dd:dd:85b/1282c19:dd:c25:c25d:dd:dd:dd:85b
932c19:dd:c25:c25d:dd:dd:dd:85c/1282c19:dd:c25:c25d:dd:dd:dd:85c
942c19:dd:c25:c25d:dd:dd:dd:85d/1282c19:dd:c25:c25d:dd:dd:dd:85d
952c19:dd:c25:c25d:dd:dd:dd:85e/1282c19:dd:c25:c25d:dd:dd:dd:85e
962c19:dd:c25:c25d:dd:dd:dd:85f/1282c19:dd:c25:c25d:dd:dd:dd:85f
972c19:dd:c25:c25d:dd:dd:dd:860/1282c19:dd:c25:c25d:dd:dd:dd:860
982c19:dd:c25:c25d:dd:dd:dd:861/1282c19:dd:c25:c25d:dd:dd:dd:861
992c19:dd:c25:c25d:dd:dd:dd:862/1282c19:dd:c25:c25d:dd:dd:dd:862
1002c19:dd:c25:c25d:dd:dd:dd:863/1282c19:dd:c25:c25d:dd:dd:dd:863
1012c19:dd:c25:c25d:dd:dd:dd:864/1282c19:dd:c25:c25d:dd:dd:dd:864
1022c19:dd:c25:c25d:dd:dd:dd:865/1282c19:dd:c25:c25d:dd:dd:dd:865
1032c19:dd:c25:c25d:dd:dd:dd:866/1282c19:dd:c25:c25d:dd:dd:dd:866
1042c19:dd:c25:c25d:dd:dd:dd:867/1282c19:dd:c25:c25d:dd:dd:dd:867
1052c19:dd:c25:c25d:dd:dd:dd:868/1282c19:dd:c25:c25d:dd:dd:dd:868
1062c19:dd:c25:c25d:dd:dd:dd:869/1282c19:dd:c25:c25d:dd:dd:dd:869
1072c19:dd:c25:c25d:dd:dd:dd:86a/1282c19:dd:c25:c25d:dd:dd:dd:86a
1082c19:dd:c25:c25d:dd:dd:dd:86b/1282c19:dd:c25:c25d:dd:dd:dd:86b
1092c19:dd:c25:c25d:dd:dd:dd:86c/1282c19:dd:c25:c25d:dd:dd:dd:86c
1102c19:dd:c25:c25d:dd:dd:dd:86d/1282c19:dd:c25:c25d:dd:dd:dd:86d
1112c19:dd:c25:c25d:dd:dd:dd:86e/1282c19:dd:c25:c25d:dd:dd:dd:86e
1122c19:dd:c25:c25d:dd:dd:dd:86f/1282c19:dd:c25:c25d:dd:dd:dd:86f
1132c19:dd:c25:c25d:dd:dd:dd:870/1282c19:dd:c25:c25d:dd:dd:dd:870
1142c19:dd:c25:c25d:dd:dd:dd:871/1282c19:dd:c25:c25d:dd:dd:dd:871
1152c19:dd:c25:c25d:dd:dd:dd:872/1282c19:dd:c25:c25d:dd:dd:dd:872
1162c19:dd:c25:c25d:dd:dd:dd:873/1282c19:dd:c25:c25d:dd:dd:dd:873
1172c19:dd:c25:c25d:dd:dd:dd:874/1282c19:dd:c25:c25d:dd:dd:dd:874
1182c19:dd:c25:c25d:dd:dd:dd:875/1282c19:dd:c25:c25d:dd:dd:dd:875
1192c19:dd:c25:c25d:dd:dd:dd:876/1282c19:dd:c25:c25d:dd:dd:dd:876
1202c19:dd:c25:c25d:dd:dd:dd:877/1282c19:dd:c25:c25d:dd:dd:dd:877
1212c19:dd:c25:c25d:dd:dd:dd:878/1282c19:dd:c25:c25d:dd:dd:dd:878
1222c19:dd:c25:c25d:dd:dd:dd:879/1282c19:dd:c25:c25d:dd:dd:dd:879
1232c19:dd:c25:c25d:dd:dd:dd:87a/1282c19:dd:c25:c25d:dd:dd:dd:87a
1242c19:dd:c25:c25d:dd:dd:dd:87b/1282c19:dd:c25:c25d:dd:dd:dd:87b
1252c19:dd:c25:c25d:dd:dd:dd:87c/1282c19:dd:c25:c25d:dd:dd:dd:87c
1262c19:dd:c25:c25d:dd:dd:dd:87d/1282c19:dd:c25:c25d:dd:dd:dd:87d
1272c19:dd:c25:c25d:dd:dd:dd:87e/1282c19:dd:c25:c25d:dd:dd:dd:87e
1282c19:dd:c25:c25d:dd:dd:dd:87f/1282c19:dd:c25:c25d:dd:dd:dd:87f
1292c19:dd:c25:c25d:dd:dd:dd:880/1282c19:dd:c25:c25d:dd:dd:dd:880
1302c19:dd:c25:c25d:dd:dd:dd:881/1282c19:dd:c25:c25d:dd:dd:dd:881
1312c19:dd:c25:c25d:dd:dd:dd:882/1282c19:dd:c25:c25d:dd:dd:dd:882
1322c19:dd:c25:c25d:dd:dd:dd:883/1282c19:dd:c25:c25d:dd:dd:dd:883
1332c19:dd:c25:c25d:dd:dd:dd:884/1282c19:dd:c25:c25d:dd:dd:dd:884
1342c19:dd:c25:c25d:dd:dd:dd:885/1282c19:dd:c25:c25d:dd:dd:dd:885
1352c19:dd:c25:c25d:dd:dd:dd:886/1282c19:dd:c25:c25d:dd:dd:dd:886
1362c19:dd:c25:c25d:dd:dd:dd:887/1282c19:dd:c25:c25d:dd:dd:dd:887
1372c19:dd:c25:c25d:dd:dd:dd:888/1282c19:dd:c25:c25d:dd:dd:dd:888
1382c19:dd:c25:c25d:dd:dd:dd:889/1282c19:dd:c25:c25d:dd:dd:dd:889
1392c19:dd:c25:c25d:dd:dd:dd:88a/1282c19:dd:c25:c25d:dd:dd:dd:88a
1402c19:dd:c25:c25d:dd:dd:dd:88b/1282c19:dd:c25:c25d:dd:dd:dd:88b
1412c19:dd:c25:c25d:dd:dd:dd:88c/1282c19:dd:c25:c25d:dd:dd:dd:88c
1422c19:dd:c25:c25d:dd:dd:dd:88d/1282c19:dd:c25:c25d:dd:dd:dd:88d
1432c19:dd:c25:c25d:dd:dd:dd:88e/1282c19:dd:c25:c25d:dd:dd:dd:88e
1442c19:dd:c25:c25d:dd:dd:dd:88f/1282c19:dd:c25:c25d:dd:dd:dd:88f
1452c19:dd:c25:c25d:dd:dd:dd:890/1282c19:dd:c25:c25d:dd:dd:dd:890
1462c19:dd:c25:c25d:dd:dd:dd:891/1282c19:dd:c25:c25d:dd:dd:dd:891
1472c19:dd:c25:c25d:dd:dd:dd:892/1282c19:dd:c25:c25d:dd:dd:dd:892
1482c19:dd:c25:c25d:dd:dd:dd:893/1282c19:dd:c25:c25d:dd:dd:dd:893
1492c19:dd:c25:c25d:dd:dd:dd:894/1282c19:dd:c25:c25d:dd:dd:dd:894
1502c19:dd:c25:c25d:dd:dd:dd:895/1282c19:dd:c25:c25d:dd:dd:dd:895
1512c19:dd:c25:c25d:dd:dd:dd:896/1282c19:dd:c25:c25d:dd:dd:dd:896
1522c19:dd:c25:c25d:dd:dd:dd:897/1282c19:dd:c25:c25d:dd:dd:dd:897
1532c19:dd:c25:c25d:dd:dd:dd:898/1282c19:dd:c25:c25d:dd:dd:dd:898
1542c19:dd:c25:c25d:dd:dd:dd:899/1282c19:dd:c25:c25d:dd:dd:dd:899
1552c19:dd:c25:c25d:dd:dd:dd:89a/1282c19:dd:c25:c25d:dd:dd:dd:89a
1562c19:dd:c25:c25d:dd:dd:dd:89b/1282c19:dd:c25:c25d:dd:dd:dd:89b
1572c19:dd:c25:c25d:dd:dd:dd:89c/1282c19:dd:c25:c25d:dd:dd:dd:89c
1582c19:dd:c25:c25d:dd:dd:dd:89d/1282c19:dd:c25:c25d:dd:dd:dd:89d
1592c19:dd:c25:c25d:dd:dd:dd:89e/1282c19:dd:c25:c25d:dd:dd:dd:89e
1602c19:dd:c25:c25d:dd:dd:dd:89f/1282c19:dd:c25:c25d:dd:dd:dd:89f
1612c19:dd:c25:c25d:dd:dd:dd:8a0/1282c19:dd:c25:c25d:dd:dd:dd:8a0
1622c19:dd:c25:c25d:dd:dd:dd:8a1/1282c19:dd:c25:c25d:dd:dd:dd:8a1
1632c19:dd:c25:c25d:dd:dd:dd:8a2/1282c19:dd:c25:c25d:dd:dd:dd:8a2
1642c19:dd:c25:c25d:dd:dd:dd:8a3/1282c19:dd:c25:c25d:dd:dd:dd:8a3
1652c19:dd:c25:c25d:dd:dd:dd:8a4/1282c19:dd:c25:c25d:dd:dd:dd:8a4
1662c19:dd:c25:c25d:dd:dd:dd:8a5/1282c19:dd:c25:c25d:dd:dd:dd:8a5
1672c19:dd:c25:c25d:dd:dd:dd:8a6/1282c19:dd:c25:c25d:dd:dd:dd:8a6
1682c19:dd:c25:c25d:dd:dd:dd:8a7/1282c19:dd:c25:c25d:dd:dd:dd:8a7
1692c19:dd:c25:c25d:dd:dd:dd:8a8/1282c19:dd:c25:c25d:dd:dd:dd:8a8
1702c19:dd:c25:c25d:dd:dd:dd:8a9/1282c19:dd:c25:c25d:dd:dd:dd:8a9
1712c19:dd:c25:c25d:dd:dd:dd:8aa/1282c19:dd:c25:c25d:dd:dd:dd:8aa
1722c19:dd:c25:c25d:dd:dd:dd:8ab/1282c19:dd:c25:c25d:dd:dd:dd:8ab
1732c19:dd:c25:c25d:dd:dd:dd:8ac/1282c19:dd:c25:c25d:dd:dd:dd:8ac
1742c19:dd:c25:c25d:dd:dd:dd:8ad/1282c19:dd:c25:c25d:dd:dd:dd:8ad
1752c19:dd:c25:c25d:dd:dd:dd:8ae/1282c19:dd:c25:c25d:dd:dd:dd:8ae
1762c19:dd:c25:c25d:dd:dd:dd:8af/1282c19:dd:c25:c25d:dd:dd:dd:8af
1772c19:dd:c25:c25d:dd:dd:dd:8b0/1282c19:dd:c25:c25d:dd:dd:dd:8b0
1782c19:dd:c25:c25d:dd:dd:dd:8b1/1282c19:dd:c25:c25d:dd:dd:dd:8b1
1792c19:dd:c25:c25d:dd:dd:dd:8b2/1282c19:dd:c25:c25d:dd:dd:dd:8b2
1802c19:dd:c25:c25d:dd:dd:dd:8b3/1282c19:dd:c25:c25d:dd:dd:dd:8b3
1812c19:dd:c25:c25d:dd:dd:dd:8b4/1282c19:dd:c25:c25d:dd:dd:dd:8b4
1822c19:dd:c25:c25d:dd:dd:dd:8b5/1282c19:dd:c25:c25d:dd:dd:dd:8b5
1832c19:dd:c25:c25d:dd:dd:dd:8b6/1282c19:dd:c25:c25d:dd:dd:dd:8b6
1842c19:dd:c25:c25d:dd:dd:dd:8b7/1282c19:dd:c25:c25d:dd:dd:dd:8b7
1852c19:dd:c25:c25d:dd:dd:dd:8b8/1282c19:dd:c25:c25d:dd:dd:dd:8b8
1862c19:dd:c25:c25d:dd:dd:dd:8b9/1282c19:dd:c25:c25d:dd:dd:dd:8b9
1872c19:dd:c25:c25d:dd:dd:dd:8ba/1282c19:dd:c25:c25d:dd:dd:dd:8ba
1882c19:dd:c25:c25d:dd:dd:dd:8bb/1282c19:dd:c25:c25d:dd:dd:dd:8bb
1892c19:dd:c25:c25d:dd:dd:dd:8bc/1282c19:dd:c25:c25d:dd:dd:dd:8bc
1902c19:dd:c25:c25d:dd:dd:dd:8bd/1282c19:dd:c25:c25d:dd:dd:dd:8bd
1912c19:dd:c25:c25d:dd:dd:dd:8be/1282c19:dd:c25:c25d:dd:dd:dd:8be
1922c19:dd:c25:c25d:dd:dd:dd:8bf/1282c19:dd:c25:c25d:dd:dd:dd:8bf
1932c19:dd:c25:c25d:dd:dd:dd:8c0/1282c19:dd:c25:c25d:dd:dd:dd:8c0
1942c19:dd:c25:c25d:dd:dd:dd:8c1/1282c19:dd:c25:c25d:dd:dd:dd:8c1
1952c19:dd:c25:c25d:dd:dd:dd:8c2/1282c19:dd:c25:c25d:dd:dd:dd:8c2
1962c19:dd:c25:c25d:dd:dd:dd:8c3/1282c19:dd:c25:c25d:dd:dd:dd:8c3
1972c19:dd:c25:c25d:dd:dd:dd:8c4/1282c19:dd:c25:c25d:dd:dd:dd:8c4
1982c19:dd:c25:c25d:dd:dd:dd:8c5/1282c19:dd:c25:c25d:dd:dd:dd:8c5
1992c19:dd:c25:c25d:dd:dd:dd:8c6/1282c19:dd:c25:c25d:dd:dd:dd:8c6
2002c19:dd:c25:c25d:dd:dd:dd:8c7/1282c19:dd:c25:c25d:dd:dd:dd:8c7
2012c19:dd:c25:c25d:dd:dd:dd:8c8/1282c19:dd:c25:c25d:dd:dd:dd:8c8
2022c19:dd:c25:c25d:dd:dd:dd:8c9/1282c19:dd:c25:c25d:dd:dd:dd:8c9
2032c19:dd:c25:c25d:dd:dd:dd:8ca/1282c19:dd:c25:c25d:dd:dd:dd:8ca
2042c19:dd:c25:c25d:dd:dd:dd:8cb/1282c19:dd:c25:c25d:dd:dd:dd:8cb
2052c19:dd:c25:c25d:dd:dd:dd:8cc/1282c19:dd:c25:c25d:dd:dd:dd:8cc
2062c19:dd:c25:c25d:dd:dd:dd:8cd/1282c19:dd:c25:c25d:dd:dd:dd:8cd
2072c19:dd:c25:c25d:dd:dd:dd:8ce/1282c19:dd:c25:c25d:dd:dd:dd:8ce
2082c19:dd:c25:c25d:dd:dd:dd:8cf/1282c19:dd:c25:c25d:dd:dd:dd:8cf
2092c19:dd:c25:c25d:dd:dd:dd:8d0/1282c19:dd:c25:c25d:dd:dd:dd:8d0
2102c19:dd:c25:c25d:dd:dd:dd:8d1/1282c19:dd:c25:c25d:dd:dd:dd:8d1
2112c19:dd:c25:c25d:dd:dd:dd:8d2/1282c19:dd:c25:c25d:dd:dd:dd:8d2
2122c19:dd:c25:c25d:dd:dd:dd:8d3/1282c19:dd:c25:c25d:dd:dd:dd:8d3
2132c19:dd:c25:c25d:dd:dd:dd:8d4/1282c19:dd:c25:c25d:dd:dd:dd:8d4
2142c19:dd:c25:c25d:dd:dd:dd:8d5/1282c19:dd:c25:c25d:dd:dd:dd:8d5
2152c19:dd:c25:c25d:dd:dd:dd:8d6/1282c19:dd:c25:c25d:dd:dd:dd:8d6
2162c19:dd:c25:c25d:dd:dd:dd:8d7/1282c19:dd:c25:c25d:dd:dd:dd:8d7
2172c19:dd:c25:c25d:dd:dd:dd:8d8/1282c19:dd:c25:c25d:dd:dd:dd:8d8
2182c19:dd:c25:c25d:dd:dd:dd:8d9/1282c19:dd:c25:c25d:dd:dd:dd:8d9
2192c19:dd:c25:c25d:dd:dd:dd:8da/1282c19:dd:c25:c25d:dd:dd:dd:8da
2202c19:dd:c25:c25d:dd:dd:dd:8db/1282c19:dd:c25:c25d:dd:dd:dd:8db
2212c19:dd:c25:c25d:dd:dd:dd:8dc/1282c19:dd:c25:c25d:dd:dd:dd:8dc
2222c19:dd:c25:c25d:dd:dd:dd:8dd/1282c19:dd:c25:c25d:dd:dd:dd:8dd
2232c19:dd:c25:c25d:dd:dd:dd:8de/1282c19:dd:c25:c25d:dd:dd:dd:8de
2242c19:dd:c25:c25d:dd:dd:dd:8df/1282c19:dd:c25:c25d:dd:dd:dd:8df
2252c19:dd:c25:c25d:dd:dd:dd:8e0/1282c19:dd:c25:c25d:dd:dd:dd:8e0
2262c19:dd:c25:c25d:dd:dd:dd:8e1/1282c19:dd:c25:c25d:dd:dd:dd:8e1
2272c19:dd:c25:c25d:dd:dd:dd:8e2/1282c19:dd:c25:c25d:dd:dd:dd:8e2
2282c19:dd:c25:c25d:dd:dd:dd:8e3/1282c19:dd:c25:c25d:dd:dd:dd:8e3
2292c19:dd:c25:c25d:dd:dd:dd:8e4/1282c19:dd:c25:c25d:dd:dd:dd:8e4
2302c19:dd:c25:c25d:dd:dd:dd:8e5/1282c19:dd:c25:c25d:dd:dd:dd:8e5
2312c19:dd:c25:c25d:dd:dd:dd:8e6/1282c19:dd:c25:c25d:dd:dd:dd:8e6
2322c19:dd:c25:c25d:dd:dd:dd:8e7/1282c19:dd:c25:c25d:dd:dd:dd:8e7
2332c19:dd:c25:c25d:dd:dd:dd:8e8/1282c19:dd:c25:c25d:dd:dd:dd:8e8
2342c19:dd:c25:c25d:dd:dd:dd:8e9/1282c19:dd:c25:c25d:dd:dd:dd:8e9
2352c19:dd:c25:c25d:dd:dd:dd:8ea/1282c19:dd:c25:c25d:dd:dd:dd:8ea
2362c19:dd:c25:c25d:dd:dd:dd:8eb/1282c19:dd:c25:c25d:dd:dd:dd:8eb
2372c19:dd:c25:c25d:dd:dd:dd:8ec/1282c19:dd:c25:c25d:dd:dd:dd:8ec
2382c19:dd:c25:c25d:dd:dd:dd:8ed/1282c19:dd:c25:c25d:dd:dd:dd:8ed
2392c19:dd:c25:c25d:dd:dd:dd:8ee/1282c19:dd:c25:c25d:dd:dd:dd:8ee
2402c19:dd:c25:c25d:dd:dd:dd:8ef/1282c19:dd:c25:c25d:dd:dd:dd:8ef
2412c19:dd:c25:c25d:dd:dd:dd:8f0/1282c19:dd:c25:c25d:dd:dd:dd:8f0
2422c19:dd:c25:c25d:dd:dd:dd:8f1/1282c19:dd:c25:c25d:dd:dd:dd:8f1
2432c19:dd:c25:c25d:dd:dd:dd:8f2/1282c19:dd:c25:c25d:dd:dd:dd:8f2
2442c19:dd:c25:c25d:dd:dd:dd:8f3/1282c19:dd:c25:c25d:dd:dd:dd:8f3
2452c19:dd:c25:c25d:dd:dd:dd:8f4/1282c19:dd:c25:c25d:dd:dd:dd:8f4
2462c19:dd:c25:c25d:dd:dd:dd:8f5/1282c19:dd:c25:c25d:dd:dd:dd:8f5
2472c19:dd:c25:c25d:dd:dd:dd:8f6/1282c19:dd:c25:c25d:dd:dd:dd:8f6
2482c19:dd:c25:c25d:dd:dd:dd:8f7/1282c19:dd:c25:c25d:dd:dd:dd:8f7
2492c19:dd:c25:c25d:dd:dd:dd:8f8/1282c19:dd:c25:c25d:dd:dd:dd:8f8
2502c19:dd:c25:c25d:dd:dd:dd:8f9/1282c19:dd:c25:c25d:dd:dd:dd:8f9
2512c19:dd:c25:c25d:dd:dd:dd:8fa/1282c19:dd:c25:c25d:dd:dd:dd:8fa
2522c19:dd:c25:c25d:dd:dd:dd:8fb/1282c19:dd:c25:c25d:dd:dd:dd:8fb
2532c19:dd:c25:c25d:dd:dd:dd:8fc/1282c19:dd:c25:c25d:dd:dd:dd:8fc
2542c19:dd:c25:c25d:dd:dd:dd:8fd/1282c19:dd:c25:c25d:dd:dd:dd:8fd
2552c19:dd:c25:c25d:dd:dd:dd:8fe/1282c19:dd:c25:c25d:dd:dd:dd:8fe
2562c19:dd:c25:c25d:dd:dd:dd:8ff/1282c19:dd:c25:c25d:dd:dd:dd:8ff

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.