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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:c25b:d00a:7900/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:7900
Last address
2c19:dd:d9:dd:c25:c25b:d00a:79ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:7900
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.7.a.0.0.d.b.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:c25b:d00a:7900/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:7900/1282c19:dd:d9:dd:c25:c25b:d00a:7900
22c19:dd:d9:dd:c25:c25b:d00a:7901/1282c19:dd:d9:dd:c25:c25b:d00a:7901
32c19:dd:d9:dd:c25:c25b:d00a:7902/1282c19:dd:d9:dd:c25:c25b:d00a:7902
42c19:dd:d9:dd:c25:c25b:d00a:7903/1282c19:dd:d9:dd:c25:c25b:d00a:7903
52c19:dd:d9:dd:c25:c25b:d00a:7904/1282c19:dd:d9:dd:c25:c25b:d00a:7904
62c19:dd:d9:dd:c25:c25b:d00a:7905/1282c19:dd:d9:dd:c25:c25b:d00a:7905
72c19:dd:d9:dd:c25:c25b:d00a:7906/1282c19:dd:d9:dd:c25:c25b:d00a:7906
82c19:dd:d9:dd:c25:c25b:d00a:7907/1282c19:dd:d9:dd:c25:c25b:d00a:7907
92c19:dd:d9:dd:c25:c25b:d00a:7908/1282c19:dd:d9:dd:c25:c25b:d00a:7908
102c19:dd:d9:dd:c25:c25b:d00a:7909/1282c19:dd:d9:dd:c25:c25b:d00a:7909
112c19:dd:d9:dd:c25:c25b:d00a:790a/1282c19:dd:d9:dd:c25:c25b:d00a:790a
122c19:dd:d9:dd:c25:c25b:d00a:790b/1282c19:dd:d9:dd:c25:c25b:d00a:790b
132c19:dd:d9:dd:c25:c25b:d00a:790c/1282c19:dd:d9:dd:c25:c25b:d00a:790c
142c19:dd:d9:dd:c25:c25b:d00a:790d/1282c19:dd:d9:dd:c25:c25b:d00a:790d
152c19:dd:d9:dd:c25:c25b:d00a:790e/1282c19:dd:d9:dd:c25:c25b:d00a:790e
162c19:dd:d9:dd:c25:c25b:d00a:790f/1282c19:dd:d9:dd:c25:c25b:d00a:790f
172c19:dd:d9:dd:c25:c25b:d00a:7910/1282c19:dd:d9:dd:c25:c25b:d00a:7910
182c19:dd:d9:dd:c25:c25b:d00a:7911/1282c19:dd:d9:dd:c25:c25b:d00a:7911
192c19:dd:d9:dd:c25:c25b:d00a:7912/1282c19:dd:d9:dd:c25:c25b:d00a:7912
202c19:dd:d9:dd:c25:c25b:d00a:7913/1282c19:dd:d9:dd:c25:c25b:d00a:7913
212c19:dd:d9:dd:c25:c25b:d00a:7914/1282c19:dd:d9:dd:c25:c25b:d00a:7914
222c19:dd:d9:dd:c25:c25b:d00a:7915/1282c19:dd:d9:dd:c25:c25b:d00a:7915
232c19:dd:d9:dd:c25:c25b:d00a:7916/1282c19:dd:d9:dd:c25:c25b:d00a:7916
242c19:dd:d9:dd:c25:c25b:d00a:7917/1282c19:dd:d9:dd:c25:c25b:d00a:7917
252c19:dd:d9:dd:c25:c25b:d00a:7918/1282c19:dd:d9:dd:c25:c25b:d00a:7918
262c19:dd:d9:dd:c25:c25b:d00a:7919/1282c19:dd:d9:dd:c25:c25b:d00a:7919
272c19:dd:d9:dd:c25:c25b:d00a:791a/1282c19:dd:d9:dd:c25:c25b:d00a:791a
282c19:dd:d9:dd:c25:c25b:d00a:791b/1282c19:dd:d9:dd:c25:c25b:d00a:791b
292c19:dd:d9:dd:c25:c25b:d00a:791c/1282c19:dd:d9:dd:c25:c25b:d00a:791c
302c19:dd:d9:dd:c25:c25b:d00a:791d/1282c19:dd:d9:dd:c25:c25b:d00a:791d
312c19:dd:d9:dd:c25:c25b:d00a:791e/1282c19:dd:d9:dd:c25:c25b:d00a:791e
322c19:dd:d9:dd:c25:c25b:d00a:791f/1282c19:dd:d9:dd:c25:c25b:d00a:791f
332c19:dd:d9:dd:c25:c25b:d00a:7920/1282c19:dd:d9:dd:c25:c25b:d00a:7920
342c19:dd:d9:dd:c25:c25b:d00a:7921/1282c19:dd:d9:dd:c25:c25b:d00a:7921
352c19:dd:d9:dd:c25:c25b:d00a:7922/1282c19:dd:d9:dd:c25:c25b:d00a:7922
362c19:dd:d9:dd:c25:c25b:d00a:7923/1282c19:dd:d9:dd:c25:c25b:d00a:7923
372c19:dd:d9:dd:c25:c25b:d00a:7924/1282c19:dd:d9:dd:c25:c25b:d00a:7924
382c19:dd:d9:dd:c25:c25b:d00a:7925/1282c19:dd:d9:dd:c25:c25b:d00a:7925
392c19:dd:d9:dd:c25:c25b:d00a:7926/1282c19:dd:d9:dd:c25:c25b:d00a:7926
402c19:dd:d9:dd:c25:c25b:d00a:7927/1282c19:dd:d9:dd:c25:c25b:d00a:7927
412c19:dd:d9:dd:c25:c25b:d00a:7928/1282c19:dd:d9:dd:c25:c25b:d00a:7928
422c19:dd:d9:dd:c25:c25b:d00a:7929/1282c19:dd:d9:dd:c25:c25b:d00a:7929
432c19:dd:d9:dd:c25:c25b:d00a:792a/1282c19:dd:d9:dd:c25:c25b:d00a:792a
442c19:dd:d9:dd:c25:c25b:d00a:792b/1282c19:dd:d9:dd:c25:c25b:d00a:792b
452c19:dd:d9:dd:c25:c25b:d00a:792c/1282c19:dd:d9:dd:c25:c25b:d00a:792c
462c19:dd:d9:dd:c25:c25b:d00a:792d/1282c19:dd:d9:dd:c25:c25b:d00a:792d
472c19:dd:d9:dd:c25:c25b:d00a:792e/1282c19:dd:d9:dd:c25:c25b:d00a:792e
482c19:dd:d9:dd:c25:c25b:d00a:792f/1282c19:dd:d9:dd:c25:c25b:d00a:792f
492c19:dd:d9:dd:c25:c25b:d00a:7930/1282c19:dd:d9:dd:c25:c25b:d00a:7930
502c19:dd:d9:dd:c25:c25b:d00a:7931/1282c19:dd:d9:dd:c25:c25b:d00a:7931
512c19:dd:d9:dd:c25:c25b:d00a:7932/1282c19:dd:d9:dd:c25:c25b:d00a:7932
522c19:dd:d9:dd:c25:c25b:d00a:7933/1282c19:dd:d9:dd:c25:c25b:d00a:7933
532c19:dd:d9:dd:c25:c25b:d00a:7934/1282c19:dd:d9:dd:c25:c25b:d00a:7934
542c19:dd:d9:dd:c25:c25b:d00a:7935/1282c19:dd:d9:dd:c25:c25b:d00a:7935
552c19:dd:d9:dd:c25:c25b:d00a:7936/1282c19:dd:d9:dd:c25:c25b:d00a:7936
562c19:dd:d9:dd:c25:c25b:d00a:7937/1282c19:dd:d9:dd:c25:c25b:d00a:7937
572c19:dd:d9:dd:c25:c25b:d00a:7938/1282c19:dd:d9:dd:c25:c25b:d00a:7938
582c19:dd:d9:dd:c25:c25b:d00a:7939/1282c19:dd:d9:dd:c25:c25b:d00a:7939
592c19:dd:d9:dd:c25:c25b:d00a:793a/1282c19:dd:d9:dd:c25:c25b:d00a:793a
602c19:dd:d9:dd:c25:c25b:d00a:793b/1282c19:dd:d9:dd:c25:c25b:d00a:793b
612c19:dd:d9:dd:c25:c25b:d00a:793c/1282c19:dd:d9:dd:c25:c25b:d00a:793c
622c19:dd:d9:dd:c25:c25b:d00a:793d/1282c19:dd:d9:dd:c25:c25b:d00a:793d
632c19:dd:d9:dd:c25:c25b:d00a:793e/1282c19:dd:d9:dd:c25:c25b:d00a:793e
642c19:dd:d9:dd:c25:c25b:d00a:793f/1282c19:dd:d9:dd:c25:c25b:d00a:793f
652c19:dd:d9:dd:c25:c25b:d00a:7940/1282c19:dd:d9:dd:c25:c25b:d00a:7940
662c19:dd:d9:dd:c25:c25b:d00a:7941/1282c19:dd:d9:dd:c25:c25b:d00a:7941
672c19:dd:d9:dd:c25:c25b:d00a:7942/1282c19:dd:d9:dd:c25:c25b:d00a:7942
682c19:dd:d9:dd:c25:c25b:d00a:7943/1282c19:dd:d9:dd:c25:c25b:d00a:7943
692c19:dd:d9:dd:c25:c25b:d00a:7944/1282c19:dd:d9:dd:c25:c25b:d00a:7944
702c19:dd:d9:dd:c25:c25b:d00a:7945/1282c19:dd:d9:dd:c25:c25b:d00a:7945
712c19:dd:d9:dd:c25:c25b:d00a:7946/1282c19:dd:d9:dd:c25:c25b:d00a:7946
722c19:dd:d9:dd:c25:c25b:d00a:7947/1282c19:dd:d9:dd:c25:c25b:d00a:7947
732c19:dd:d9:dd:c25:c25b:d00a:7948/1282c19:dd:d9:dd:c25:c25b:d00a:7948
742c19:dd:d9:dd:c25:c25b:d00a:7949/1282c19:dd:d9:dd:c25:c25b:d00a:7949
752c19:dd:d9:dd:c25:c25b:d00a:794a/1282c19:dd:d9:dd:c25:c25b:d00a:794a
762c19:dd:d9:dd:c25:c25b:d00a:794b/1282c19:dd:d9:dd:c25:c25b:d00a:794b
772c19:dd:d9:dd:c25:c25b:d00a:794c/1282c19:dd:d9:dd:c25:c25b:d00a:794c
782c19:dd:d9:dd:c25:c25b:d00a:794d/1282c19:dd:d9:dd:c25:c25b:d00a:794d
792c19:dd:d9:dd:c25:c25b:d00a:794e/1282c19:dd:d9:dd:c25:c25b:d00a:794e
802c19:dd:d9:dd:c25:c25b:d00a:794f/1282c19:dd:d9:dd:c25:c25b:d00a:794f
812c19:dd:d9:dd:c25:c25b:d00a:7950/1282c19:dd:d9:dd:c25:c25b:d00a:7950
822c19:dd:d9:dd:c25:c25b:d00a:7951/1282c19:dd:d9:dd:c25:c25b:d00a:7951
832c19:dd:d9:dd:c25:c25b:d00a:7952/1282c19:dd:d9:dd:c25:c25b:d00a:7952
842c19:dd:d9:dd:c25:c25b:d00a:7953/1282c19:dd:d9:dd:c25:c25b:d00a:7953
852c19:dd:d9:dd:c25:c25b:d00a:7954/1282c19:dd:d9:dd:c25:c25b:d00a:7954
862c19:dd:d9:dd:c25:c25b:d00a:7955/1282c19:dd:d9:dd:c25:c25b:d00a:7955
872c19:dd:d9:dd:c25:c25b:d00a:7956/1282c19:dd:d9:dd:c25:c25b:d00a:7956
882c19:dd:d9:dd:c25:c25b:d00a:7957/1282c19:dd:d9:dd:c25:c25b:d00a:7957
892c19:dd:d9:dd:c25:c25b:d00a:7958/1282c19:dd:d9:dd:c25:c25b:d00a:7958
902c19:dd:d9:dd:c25:c25b:d00a:7959/1282c19:dd:d9:dd:c25:c25b:d00a:7959
912c19:dd:d9:dd:c25:c25b:d00a:795a/1282c19:dd:d9:dd:c25:c25b:d00a:795a
922c19:dd:d9:dd:c25:c25b:d00a:795b/1282c19:dd:d9:dd:c25:c25b:d00a:795b
932c19:dd:d9:dd:c25:c25b:d00a:795c/1282c19:dd:d9:dd:c25:c25b:d00a:795c
942c19:dd:d9:dd:c25:c25b:d00a:795d/1282c19:dd:d9:dd:c25:c25b:d00a:795d
952c19:dd:d9:dd:c25:c25b:d00a:795e/1282c19:dd:d9:dd:c25:c25b:d00a:795e
962c19:dd:d9:dd:c25:c25b:d00a:795f/1282c19:dd:d9:dd:c25:c25b:d00a:795f
972c19:dd:d9:dd:c25:c25b:d00a:7960/1282c19:dd:d9:dd:c25:c25b:d00a:7960
982c19:dd:d9:dd:c25:c25b:d00a:7961/1282c19:dd:d9:dd:c25:c25b:d00a:7961
992c19:dd:d9:dd:c25:c25b:d00a:7962/1282c19:dd:d9:dd:c25:c25b:d00a:7962
1002c19:dd:d9:dd:c25:c25b:d00a:7963/1282c19:dd:d9:dd:c25:c25b:d00a:7963
1012c19:dd:d9:dd:c25:c25b:d00a:7964/1282c19:dd:d9:dd:c25:c25b:d00a:7964
1022c19:dd:d9:dd:c25:c25b:d00a:7965/1282c19:dd:d9:dd:c25:c25b:d00a:7965
1032c19:dd:d9:dd:c25:c25b:d00a:7966/1282c19:dd:d9:dd:c25:c25b:d00a:7966
1042c19:dd:d9:dd:c25:c25b:d00a:7967/1282c19:dd:d9:dd:c25:c25b:d00a:7967
1052c19:dd:d9:dd:c25:c25b:d00a:7968/1282c19:dd:d9:dd:c25:c25b:d00a:7968
1062c19:dd:d9:dd:c25:c25b:d00a:7969/1282c19:dd:d9:dd:c25:c25b:d00a:7969
1072c19:dd:d9:dd:c25:c25b:d00a:796a/1282c19:dd:d9:dd:c25:c25b:d00a:796a
1082c19:dd:d9:dd:c25:c25b:d00a:796b/1282c19:dd:d9:dd:c25:c25b:d00a:796b
1092c19:dd:d9:dd:c25:c25b:d00a:796c/1282c19:dd:d9:dd:c25:c25b:d00a:796c
1102c19:dd:d9:dd:c25:c25b:d00a:796d/1282c19:dd:d9:dd:c25:c25b:d00a:796d
1112c19:dd:d9:dd:c25:c25b:d00a:796e/1282c19:dd:d9:dd:c25:c25b:d00a:796e
1122c19:dd:d9:dd:c25:c25b:d00a:796f/1282c19:dd:d9:dd:c25:c25b:d00a:796f
1132c19:dd:d9:dd:c25:c25b:d00a:7970/1282c19:dd:d9:dd:c25:c25b:d00a:7970
1142c19:dd:d9:dd:c25:c25b:d00a:7971/1282c19:dd:d9:dd:c25:c25b:d00a:7971
1152c19:dd:d9:dd:c25:c25b:d00a:7972/1282c19:dd:d9:dd:c25:c25b:d00a:7972
1162c19:dd:d9:dd:c25:c25b:d00a:7973/1282c19:dd:d9:dd:c25:c25b:d00a:7973
1172c19:dd:d9:dd:c25:c25b:d00a:7974/1282c19:dd:d9:dd:c25:c25b:d00a:7974
1182c19:dd:d9:dd:c25:c25b:d00a:7975/1282c19:dd:d9:dd:c25:c25b:d00a:7975
1192c19:dd:d9:dd:c25:c25b:d00a:7976/1282c19:dd:d9:dd:c25:c25b:d00a:7976
1202c19:dd:d9:dd:c25:c25b:d00a:7977/1282c19:dd:d9:dd:c25:c25b:d00a:7977
1212c19:dd:d9:dd:c25:c25b:d00a:7978/1282c19:dd:d9:dd:c25:c25b:d00a:7978
1222c19:dd:d9:dd:c25:c25b:d00a:7979/1282c19:dd:d9:dd:c25:c25b:d00a:7979
1232c19:dd:d9:dd:c25:c25b:d00a:797a/1282c19:dd:d9:dd:c25:c25b:d00a:797a
1242c19:dd:d9:dd:c25:c25b:d00a:797b/1282c19:dd:d9:dd:c25:c25b:d00a:797b
1252c19:dd:d9:dd:c25:c25b:d00a:797c/1282c19:dd:d9:dd:c25:c25b:d00a:797c
1262c19:dd:d9:dd:c25:c25b:d00a:797d/1282c19:dd:d9:dd:c25:c25b:d00a:797d
1272c19:dd:d9:dd:c25:c25b:d00a:797e/1282c19:dd:d9:dd:c25:c25b:d00a:797e
1282c19:dd:d9:dd:c25:c25b:d00a:797f/1282c19:dd:d9:dd:c25:c25b:d00a:797f
1292c19:dd:d9:dd:c25:c25b:d00a:7980/1282c19:dd:d9:dd:c25:c25b:d00a:7980
1302c19:dd:d9:dd:c25:c25b:d00a:7981/1282c19:dd:d9:dd:c25:c25b:d00a:7981
1312c19:dd:d9:dd:c25:c25b:d00a:7982/1282c19:dd:d9:dd:c25:c25b:d00a:7982
1322c19:dd:d9:dd:c25:c25b:d00a:7983/1282c19:dd:d9:dd:c25:c25b:d00a:7983
1332c19:dd:d9:dd:c25:c25b:d00a:7984/1282c19:dd:d9:dd:c25:c25b:d00a:7984
1342c19:dd:d9:dd:c25:c25b:d00a:7985/1282c19:dd:d9:dd:c25:c25b:d00a:7985
1352c19:dd:d9:dd:c25:c25b:d00a:7986/1282c19:dd:d9:dd:c25:c25b:d00a:7986
1362c19:dd:d9:dd:c25:c25b:d00a:7987/1282c19:dd:d9:dd:c25:c25b:d00a:7987
1372c19:dd:d9:dd:c25:c25b:d00a:7988/1282c19:dd:d9:dd:c25:c25b:d00a:7988
1382c19:dd:d9:dd:c25:c25b:d00a:7989/1282c19:dd:d9:dd:c25:c25b:d00a:7989
1392c19:dd:d9:dd:c25:c25b:d00a:798a/1282c19:dd:d9:dd:c25:c25b:d00a:798a
1402c19:dd:d9:dd:c25:c25b:d00a:798b/1282c19:dd:d9:dd:c25:c25b:d00a:798b
1412c19:dd:d9:dd:c25:c25b:d00a:798c/1282c19:dd:d9:dd:c25:c25b:d00a:798c
1422c19:dd:d9:dd:c25:c25b:d00a:798d/1282c19:dd:d9:dd:c25:c25b:d00a:798d
1432c19:dd:d9:dd:c25:c25b:d00a:798e/1282c19:dd:d9:dd:c25:c25b:d00a:798e
1442c19:dd:d9:dd:c25:c25b:d00a:798f/1282c19:dd:d9:dd:c25:c25b:d00a:798f
1452c19:dd:d9:dd:c25:c25b:d00a:7990/1282c19:dd:d9:dd:c25:c25b:d00a:7990
1462c19:dd:d9:dd:c25:c25b:d00a:7991/1282c19:dd:d9:dd:c25:c25b:d00a:7991
1472c19:dd:d9:dd:c25:c25b:d00a:7992/1282c19:dd:d9:dd:c25:c25b:d00a:7992
1482c19:dd:d9:dd:c25:c25b:d00a:7993/1282c19:dd:d9:dd:c25:c25b:d00a:7993
1492c19:dd:d9:dd:c25:c25b:d00a:7994/1282c19:dd:d9:dd:c25:c25b:d00a:7994
1502c19:dd:d9:dd:c25:c25b:d00a:7995/1282c19:dd:d9:dd:c25:c25b:d00a:7995
1512c19:dd:d9:dd:c25:c25b:d00a:7996/1282c19:dd:d9:dd:c25:c25b:d00a:7996
1522c19:dd:d9:dd:c25:c25b:d00a:7997/1282c19:dd:d9:dd:c25:c25b:d00a:7997
1532c19:dd:d9:dd:c25:c25b:d00a:7998/1282c19:dd:d9:dd:c25:c25b:d00a:7998
1542c19:dd:d9:dd:c25:c25b:d00a:7999/1282c19:dd:d9:dd:c25:c25b:d00a:7999
1552c19:dd:d9:dd:c25:c25b:d00a:799a/1282c19:dd:d9:dd:c25:c25b:d00a:799a
1562c19:dd:d9:dd:c25:c25b:d00a:799b/1282c19:dd:d9:dd:c25:c25b:d00a:799b
1572c19:dd:d9:dd:c25:c25b:d00a:799c/1282c19:dd:d9:dd:c25:c25b:d00a:799c
1582c19:dd:d9:dd:c25:c25b:d00a:799d/1282c19:dd:d9:dd:c25:c25b:d00a:799d
1592c19:dd:d9:dd:c25:c25b:d00a:799e/1282c19:dd:d9:dd:c25:c25b:d00a:799e
1602c19:dd:d9:dd:c25:c25b:d00a:799f/1282c19:dd:d9:dd:c25:c25b:d00a:799f
1612c19:dd:d9:dd:c25:c25b:d00a:79a0/1282c19:dd:d9:dd:c25:c25b:d00a:79a0
1622c19:dd:d9:dd:c25:c25b:d00a:79a1/1282c19:dd:d9:dd:c25:c25b:d00a:79a1
1632c19:dd:d9:dd:c25:c25b:d00a:79a2/1282c19:dd:d9:dd:c25:c25b:d00a:79a2
1642c19:dd:d9:dd:c25:c25b:d00a:79a3/1282c19:dd:d9:dd:c25:c25b:d00a:79a3
1652c19:dd:d9:dd:c25:c25b:d00a:79a4/1282c19:dd:d9:dd:c25:c25b:d00a:79a4
1662c19:dd:d9:dd:c25:c25b:d00a:79a5/1282c19:dd:d9:dd:c25:c25b:d00a:79a5
1672c19:dd:d9:dd:c25:c25b:d00a:79a6/1282c19:dd:d9:dd:c25:c25b:d00a:79a6
1682c19:dd:d9:dd:c25:c25b:d00a:79a7/1282c19:dd:d9:dd:c25:c25b:d00a:79a7
1692c19:dd:d9:dd:c25:c25b:d00a:79a8/1282c19:dd:d9:dd:c25:c25b:d00a:79a8
1702c19:dd:d9:dd:c25:c25b:d00a:79a9/1282c19:dd:d9:dd:c25:c25b:d00a:79a9
1712c19:dd:d9:dd:c25:c25b:d00a:79aa/1282c19:dd:d9:dd:c25:c25b:d00a:79aa
1722c19:dd:d9:dd:c25:c25b:d00a:79ab/1282c19:dd:d9:dd:c25:c25b:d00a:79ab
1732c19:dd:d9:dd:c25:c25b:d00a:79ac/1282c19:dd:d9:dd:c25:c25b:d00a:79ac
1742c19:dd:d9:dd:c25:c25b:d00a:79ad/1282c19:dd:d9:dd:c25:c25b:d00a:79ad
1752c19:dd:d9:dd:c25:c25b:d00a:79ae/1282c19:dd:d9:dd:c25:c25b:d00a:79ae
1762c19:dd:d9:dd:c25:c25b:d00a:79af/1282c19:dd:d9:dd:c25:c25b:d00a:79af
1772c19:dd:d9:dd:c25:c25b:d00a:79b0/1282c19:dd:d9:dd:c25:c25b:d00a:79b0
1782c19:dd:d9:dd:c25:c25b:d00a:79b1/1282c19:dd:d9:dd:c25:c25b:d00a:79b1
1792c19:dd:d9:dd:c25:c25b:d00a:79b2/1282c19:dd:d9:dd:c25:c25b:d00a:79b2
1802c19:dd:d9:dd:c25:c25b:d00a:79b3/1282c19:dd:d9:dd:c25:c25b:d00a:79b3
1812c19:dd:d9:dd:c25:c25b:d00a:79b4/1282c19:dd:d9:dd:c25:c25b:d00a:79b4
1822c19:dd:d9:dd:c25:c25b:d00a:79b5/1282c19:dd:d9:dd:c25:c25b:d00a:79b5
1832c19:dd:d9:dd:c25:c25b:d00a:79b6/1282c19:dd:d9:dd:c25:c25b:d00a:79b6
1842c19:dd:d9:dd:c25:c25b:d00a:79b7/1282c19:dd:d9:dd:c25:c25b:d00a:79b7
1852c19:dd:d9:dd:c25:c25b:d00a:79b8/1282c19:dd:d9:dd:c25:c25b:d00a:79b8
1862c19:dd:d9:dd:c25:c25b:d00a:79b9/1282c19:dd:d9:dd:c25:c25b:d00a:79b9
1872c19:dd:d9:dd:c25:c25b:d00a:79ba/1282c19:dd:d9:dd:c25:c25b:d00a:79ba
1882c19:dd:d9:dd:c25:c25b:d00a:79bb/1282c19:dd:d9:dd:c25:c25b:d00a:79bb
1892c19:dd:d9:dd:c25:c25b:d00a:79bc/1282c19:dd:d9:dd:c25:c25b:d00a:79bc
1902c19:dd:d9:dd:c25:c25b:d00a:79bd/1282c19:dd:d9:dd:c25:c25b:d00a:79bd
1912c19:dd:d9:dd:c25:c25b:d00a:79be/1282c19:dd:d9:dd:c25:c25b:d00a:79be
1922c19:dd:d9:dd:c25:c25b:d00a:79bf/1282c19:dd:d9:dd:c25:c25b:d00a:79bf
1932c19:dd:d9:dd:c25:c25b:d00a:79c0/1282c19:dd:d9:dd:c25:c25b:d00a:79c0
1942c19:dd:d9:dd:c25:c25b:d00a:79c1/1282c19:dd:d9:dd:c25:c25b:d00a:79c1
1952c19:dd:d9:dd:c25:c25b:d00a:79c2/1282c19:dd:d9:dd:c25:c25b:d00a:79c2
1962c19:dd:d9:dd:c25:c25b:d00a:79c3/1282c19:dd:d9:dd:c25:c25b:d00a:79c3
1972c19:dd:d9:dd:c25:c25b:d00a:79c4/1282c19:dd:d9:dd:c25:c25b:d00a:79c4
1982c19:dd:d9:dd:c25:c25b:d00a:79c5/1282c19:dd:d9:dd:c25:c25b:d00a:79c5
1992c19:dd:d9:dd:c25:c25b:d00a:79c6/1282c19:dd:d9:dd:c25:c25b:d00a:79c6
2002c19:dd:d9:dd:c25:c25b:d00a:79c7/1282c19:dd:d9:dd:c25:c25b:d00a:79c7
2012c19:dd:d9:dd:c25:c25b:d00a:79c8/1282c19:dd:d9:dd:c25:c25b:d00a:79c8
2022c19:dd:d9:dd:c25:c25b:d00a:79c9/1282c19:dd:d9:dd:c25:c25b:d00a:79c9
2032c19:dd:d9:dd:c25:c25b:d00a:79ca/1282c19:dd:d9:dd:c25:c25b:d00a:79ca
2042c19:dd:d9:dd:c25:c25b:d00a:79cb/1282c19:dd:d9:dd:c25:c25b:d00a:79cb
2052c19:dd:d9:dd:c25:c25b:d00a:79cc/1282c19:dd:d9:dd:c25:c25b:d00a:79cc
2062c19:dd:d9:dd:c25:c25b:d00a:79cd/1282c19:dd:d9:dd:c25:c25b:d00a:79cd
2072c19:dd:d9:dd:c25:c25b:d00a:79ce/1282c19:dd:d9:dd:c25:c25b:d00a:79ce
2082c19:dd:d9:dd:c25:c25b:d00a:79cf/1282c19:dd:d9:dd:c25:c25b:d00a:79cf
2092c19:dd:d9:dd:c25:c25b:d00a:79d0/1282c19:dd:d9:dd:c25:c25b:d00a:79d0
2102c19:dd:d9:dd:c25:c25b:d00a:79d1/1282c19:dd:d9:dd:c25:c25b:d00a:79d1
2112c19:dd:d9:dd:c25:c25b:d00a:79d2/1282c19:dd:d9:dd:c25:c25b:d00a:79d2
2122c19:dd:d9:dd:c25:c25b:d00a:79d3/1282c19:dd:d9:dd:c25:c25b:d00a:79d3
2132c19:dd:d9:dd:c25:c25b:d00a:79d4/1282c19:dd:d9:dd:c25:c25b:d00a:79d4
2142c19:dd:d9:dd:c25:c25b:d00a:79d5/1282c19:dd:d9:dd:c25:c25b:d00a:79d5
2152c19:dd:d9:dd:c25:c25b:d00a:79d6/1282c19:dd:d9:dd:c25:c25b:d00a:79d6
2162c19:dd:d9:dd:c25:c25b:d00a:79d7/1282c19:dd:d9:dd:c25:c25b:d00a:79d7
2172c19:dd:d9:dd:c25:c25b:d00a:79d8/1282c19:dd:d9:dd:c25:c25b:d00a:79d8
2182c19:dd:d9:dd:c25:c25b:d00a:79d9/1282c19:dd:d9:dd:c25:c25b:d00a:79d9
2192c19:dd:d9:dd:c25:c25b:d00a:79da/1282c19:dd:d9:dd:c25:c25b:d00a:79da
2202c19:dd:d9:dd:c25:c25b:d00a:79db/1282c19:dd:d9:dd:c25:c25b:d00a:79db
2212c19:dd:d9:dd:c25:c25b:d00a:79dc/1282c19:dd:d9:dd:c25:c25b:d00a:79dc
2222c19:dd:d9:dd:c25:c25b:d00a:79dd/1282c19:dd:d9:dd:c25:c25b:d00a:79dd
2232c19:dd:d9:dd:c25:c25b:d00a:79de/1282c19:dd:d9:dd:c25:c25b:d00a:79de
2242c19:dd:d9:dd:c25:c25b:d00a:79df/1282c19:dd:d9:dd:c25:c25b:d00a:79df
2252c19:dd:d9:dd:c25:c25b:d00a:79e0/1282c19:dd:d9:dd:c25:c25b:d00a:79e0
2262c19:dd:d9:dd:c25:c25b:d00a:79e1/1282c19:dd:d9:dd:c25:c25b:d00a:79e1
2272c19:dd:d9:dd:c25:c25b:d00a:79e2/1282c19:dd:d9:dd:c25:c25b:d00a:79e2
2282c19:dd:d9:dd:c25:c25b:d00a:79e3/1282c19:dd:d9:dd:c25:c25b:d00a:79e3
2292c19:dd:d9:dd:c25:c25b:d00a:79e4/1282c19:dd:d9:dd:c25:c25b:d00a:79e4
2302c19:dd:d9:dd:c25:c25b:d00a:79e5/1282c19:dd:d9:dd:c25:c25b:d00a:79e5
2312c19:dd:d9:dd:c25:c25b:d00a:79e6/1282c19:dd:d9:dd:c25:c25b:d00a:79e6
2322c19:dd:d9:dd:c25:c25b:d00a:79e7/1282c19:dd:d9:dd:c25:c25b:d00a:79e7
2332c19:dd:d9:dd:c25:c25b:d00a:79e8/1282c19:dd:d9:dd:c25:c25b:d00a:79e8
2342c19:dd:d9:dd:c25:c25b:d00a:79e9/1282c19:dd:d9:dd:c25:c25b:d00a:79e9
2352c19:dd:d9:dd:c25:c25b:d00a:79ea/1282c19:dd:d9:dd:c25:c25b:d00a:79ea
2362c19:dd:d9:dd:c25:c25b:d00a:79eb/1282c19:dd:d9:dd:c25:c25b:d00a:79eb
2372c19:dd:d9:dd:c25:c25b:d00a:79ec/1282c19:dd:d9:dd:c25:c25b:d00a:79ec
2382c19:dd:d9:dd:c25:c25b:d00a:79ed/1282c19:dd:d9:dd:c25:c25b:d00a:79ed
2392c19:dd:d9:dd:c25:c25b:d00a:79ee/1282c19:dd:d9:dd:c25:c25b:d00a:79ee
2402c19:dd:d9:dd:c25:c25b:d00a:79ef/1282c19:dd:d9:dd:c25:c25b:d00a:79ef
2412c19:dd:d9:dd:c25:c25b:d00a:79f0/1282c19:dd:d9:dd:c25:c25b:d00a:79f0
2422c19:dd:d9:dd:c25:c25b:d00a:79f1/1282c19:dd:d9:dd:c25:c25b:d00a:79f1
2432c19:dd:d9:dd:c25:c25b:d00a:79f2/1282c19:dd:d9:dd:c25:c25b:d00a:79f2
2442c19:dd:d9:dd:c25:c25b:d00a:79f3/1282c19:dd:d9:dd:c25:c25b:d00a:79f3
2452c19:dd:d9:dd:c25:c25b:d00a:79f4/1282c19:dd:d9:dd:c25:c25b:d00a:79f4
2462c19:dd:d9:dd:c25:c25b:d00a:79f5/1282c19:dd:d9:dd:c25:c25b:d00a:79f5
2472c19:dd:d9:dd:c25:c25b:d00a:79f6/1282c19:dd:d9:dd:c25:c25b:d00a:79f6
2482c19:dd:d9:dd:c25:c25b:d00a:79f7/1282c19:dd:d9:dd:c25:c25b:d00a:79f7
2492c19:dd:d9:dd:c25:c25b:d00a:79f8/1282c19:dd:d9:dd:c25:c25b:d00a:79f8
2502c19:dd:d9:dd:c25:c25b:d00a:79f9/1282c19:dd:d9:dd:c25:c25b:d00a:79f9
2512c19:dd:d9:dd:c25:c25b:d00a:79fa/1282c19:dd:d9:dd:c25:c25b:d00a:79fa
2522c19:dd:d9:dd:c25:c25b:d00a:79fb/1282c19:dd:d9:dd:c25:c25b:d00a:79fb
2532c19:dd:d9:dd:c25:c25b:d00a:79fc/1282c19:dd:d9:dd:c25:c25b:d00a:79fc
2542c19:dd:d9:dd:c25:c25b:d00a:79fd/1282c19:dd:d9:dd:c25:c25b:d00a:79fd
2552c19:dd:d9:dd:c25:c25b:d00a:79fe/1282c19:dd:d9:dd:c25:c25b:d00a:79fe
2562c19:dd:d9:dd:c25:c25b:d00a:79ff/1282c19:dd:d9:dd:c25:c25b:d00a:79ff

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.