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IP subnet calculator

Type an address with its prefix or mask to see the network, its usable range and masks. Split it into smaller subnets, or look up any prefix in the reference tables.

Prefix/120
Addresses256
/64 networksPart of one
Network
2c19:dd:d9:dd:c25:c25:94de:2900/120
First address
2c19:dd:d9:dd:c25:c25:94de:2900
Last address
2c19:dd:d9:dd:c25:c25:94de:29ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:2900
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
9.2.e.d.4.9.5.2.c.0.5.2.c.0.d.d.0.0.9.d.0.0.d.d.0.0.9.1.c.2.ip6.arpa
Split into smaller subnets/128
/121 (2)/122 (4)/123 (8)/124 (16)/127 (128)/128 (256)

2c19:dd:d9:dd:c25:c25:94de:2900/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:2900/1282c19:dd:d9:dd:c25:c25:94de:2900
22c19:dd:d9:dd:c25:c25:94de:2901/1282c19:dd:d9:dd:c25:c25:94de:2901
32c19:dd:d9:dd:c25:c25:94de:2902/1282c19:dd:d9:dd:c25:c25:94de:2902
42c19:dd:d9:dd:c25:c25:94de:2903/1282c19:dd:d9:dd:c25:c25:94de:2903
52c19:dd:d9:dd:c25:c25:94de:2904/1282c19:dd:d9:dd:c25:c25:94de:2904
62c19:dd:d9:dd:c25:c25:94de:2905/1282c19:dd:d9:dd:c25:c25:94de:2905
72c19:dd:d9:dd:c25:c25:94de:2906/1282c19:dd:d9:dd:c25:c25:94de:2906
82c19:dd:d9:dd:c25:c25:94de:2907/1282c19:dd:d9:dd:c25:c25:94de:2907
92c19:dd:d9:dd:c25:c25:94de:2908/1282c19:dd:d9:dd:c25:c25:94de:2908
102c19:dd:d9:dd:c25:c25:94de:2909/1282c19:dd:d9:dd:c25:c25:94de:2909
112c19:dd:d9:dd:c25:c25:94de:290a/1282c19:dd:d9:dd:c25:c25:94de:290a
122c19:dd:d9:dd:c25:c25:94de:290b/1282c19:dd:d9:dd:c25:c25:94de:290b
132c19:dd:d9:dd:c25:c25:94de:290c/1282c19:dd:d9:dd:c25:c25:94de:290c
142c19:dd:d9:dd:c25:c25:94de:290d/1282c19:dd:d9:dd:c25:c25:94de:290d
152c19:dd:d9:dd:c25:c25:94de:290e/1282c19:dd:d9:dd:c25:c25:94de:290e
162c19:dd:d9:dd:c25:c25:94de:290f/1282c19:dd:d9:dd:c25:c25:94de:290f
172c19:dd:d9:dd:c25:c25:94de:2910/1282c19:dd:d9:dd:c25:c25:94de:2910
182c19:dd:d9:dd:c25:c25:94de:2911/1282c19:dd:d9:dd:c25:c25:94de:2911
192c19:dd:d9:dd:c25:c25:94de:2912/1282c19:dd:d9:dd:c25:c25:94de:2912
202c19:dd:d9:dd:c25:c25:94de:2913/1282c19:dd:d9:dd:c25:c25:94de:2913
212c19:dd:d9:dd:c25:c25:94de:2914/1282c19:dd:d9:dd:c25:c25:94de:2914
222c19:dd:d9:dd:c25:c25:94de:2915/1282c19:dd:d9:dd:c25:c25:94de:2915
232c19:dd:d9:dd:c25:c25:94de:2916/1282c19:dd:d9:dd:c25:c25:94de:2916
242c19:dd:d9:dd:c25:c25:94de:2917/1282c19:dd:d9:dd:c25:c25:94de:2917
252c19:dd:d9:dd:c25:c25:94de:2918/1282c19:dd:d9:dd:c25:c25:94de:2918
262c19:dd:d9:dd:c25:c25:94de:2919/1282c19:dd:d9:dd:c25:c25:94de:2919
272c19:dd:d9:dd:c25:c25:94de:291a/1282c19:dd:d9:dd:c25:c25:94de:291a
282c19:dd:d9:dd:c25:c25:94de:291b/1282c19:dd:d9:dd:c25:c25:94de:291b
292c19:dd:d9:dd:c25:c25:94de:291c/1282c19:dd:d9:dd:c25:c25:94de:291c
302c19:dd:d9:dd:c25:c25:94de:291d/1282c19:dd:d9:dd:c25:c25:94de:291d
312c19:dd:d9:dd:c25:c25:94de:291e/1282c19:dd:d9:dd:c25:c25:94de:291e
322c19:dd:d9:dd:c25:c25:94de:291f/1282c19:dd:d9:dd:c25:c25:94de:291f
332c19:dd:d9:dd:c25:c25:94de:2920/1282c19:dd:d9:dd:c25:c25:94de:2920
342c19:dd:d9:dd:c25:c25:94de:2921/1282c19:dd:d9:dd:c25:c25:94de:2921
352c19:dd:d9:dd:c25:c25:94de:2922/1282c19:dd:d9:dd:c25:c25:94de:2922
362c19:dd:d9:dd:c25:c25:94de:2923/1282c19:dd:d9:dd:c25:c25:94de:2923
372c19:dd:d9:dd:c25:c25:94de:2924/1282c19:dd:d9:dd:c25:c25:94de:2924
382c19:dd:d9:dd:c25:c25:94de:2925/1282c19:dd:d9:dd:c25:c25:94de:2925
392c19:dd:d9:dd:c25:c25:94de:2926/1282c19:dd:d9:dd:c25:c25:94de:2926
402c19:dd:d9:dd:c25:c25:94de:2927/1282c19:dd:d9:dd:c25:c25:94de:2927
412c19:dd:d9:dd:c25:c25:94de:2928/1282c19:dd:d9:dd:c25:c25:94de:2928
422c19:dd:d9:dd:c25:c25:94de:2929/1282c19:dd:d9:dd:c25:c25:94de:2929
432c19:dd:d9:dd:c25:c25:94de:292a/1282c19:dd:d9:dd:c25:c25:94de:292a
442c19:dd:d9:dd:c25:c25:94de:292b/1282c19:dd:d9:dd:c25:c25:94de:292b
452c19:dd:d9:dd:c25:c25:94de:292c/1282c19:dd:d9:dd:c25:c25:94de:292c
462c19:dd:d9:dd:c25:c25:94de:292d/1282c19:dd:d9:dd:c25:c25:94de:292d
472c19:dd:d9:dd:c25:c25:94de:292e/1282c19:dd:d9:dd:c25:c25:94de:292e
482c19:dd:d9:dd:c25:c25:94de:292f/1282c19:dd:d9:dd:c25:c25:94de:292f
492c19:dd:d9:dd:c25:c25:94de:2930/1282c19:dd:d9:dd:c25:c25:94de:2930
502c19:dd:d9:dd:c25:c25:94de:2931/1282c19:dd:d9:dd:c25:c25:94de:2931
512c19:dd:d9:dd:c25:c25:94de:2932/1282c19:dd:d9:dd:c25:c25:94de:2932
522c19:dd:d9:dd:c25:c25:94de:2933/1282c19:dd:d9:dd:c25:c25:94de:2933
532c19:dd:d9:dd:c25:c25:94de:2934/1282c19:dd:d9:dd:c25:c25:94de:2934
542c19:dd:d9:dd:c25:c25:94de:2935/1282c19:dd:d9:dd:c25:c25:94de:2935
552c19:dd:d9:dd:c25:c25:94de:2936/1282c19:dd:d9:dd:c25:c25:94de:2936
562c19:dd:d9:dd:c25:c25:94de:2937/1282c19:dd:d9:dd:c25:c25:94de:2937
572c19:dd:d9:dd:c25:c25:94de:2938/1282c19:dd:d9:dd:c25:c25:94de:2938
582c19:dd:d9:dd:c25:c25:94de:2939/1282c19:dd:d9:dd:c25:c25:94de:2939
592c19:dd:d9:dd:c25:c25:94de:293a/1282c19:dd:d9:dd:c25:c25:94de:293a
602c19:dd:d9:dd:c25:c25:94de:293b/1282c19:dd:d9:dd:c25:c25:94de:293b
612c19:dd:d9:dd:c25:c25:94de:293c/1282c19:dd:d9:dd:c25:c25:94de:293c
622c19:dd:d9:dd:c25:c25:94de:293d/1282c19:dd:d9:dd:c25:c25:94de:293d
632c19:dd:d9:dd:c25:c25:94de:293e/1282c19:dd:d9:dd:c25:c25:94de:293e
642c19:dd:d9:dd:c25:c25:94de:293f/1282c19:dd:d9:dd:c25:c25:94de:293f
652c19:dd:d9:dd:c25:c25:94de:2940/1282c19:dd:d9:dd:c25:c25:94de:2940
662c19:dd:d9:dd:c25:c25:94de:2941/1282c19:dd:d9:dd:c25:c25:94de:2941
672c19:dd:d9:dd:c25:c25:94de:2942/1282c19:dd:d9:dd:c25:c25:94de:2942
682c19:dd:d9:dd:c25:c25:94de:2943/1282c19:dd:d9:dd:c25:c25:94de:2943
692c19:dd:d9:dd:c25:c25:94de:2944/1282c19:dd:d9:dd:c25:c25:94de:2944
702c19:dd:d9:dd:c25:c25:94de:2945/1282c19:dd:d9:dd:c25:c25:94de:2945
712c19:dd:d9:dd:c25:c25:94de:2946/1282c19:dd:d9:dd:c25:c25:94de:2946
722c19:dd:d9:dd:c25:c25:94de:2947/1282c19:dd:d9:dd:c25:c25:94de:2947
732c19:dd:d9:dd:c25:c25:94de:2948/1282c19:dd:d9:dd:c25:c25:94de:2948
742c19:dd:d9:dd:c25:c25:94de:2949/1282c19:dd:d9:dd:c25:c25:94de:2949
752c19:dd:d9:dd:c25:c25:94de:294a/1282c19:dd:d9:dd:c25:c25:94de:294a
762c19:dd:d9:dd:c25:c25:94de:294b/1282c19:dd:d9:dd:c25:c25:94de:294b
772c19:dd:d9:dd:c25:c25:94de:294c/1282c19:dd:d9:dd:c25:c25:94de:294c
782c19:dd:d9:dd:c25:c25:94de:294d/1282c19:dd:d9:dd:c25:c25:94de:294d
792c19:dd:d9:dd:c25:c25:94de:294e/1282c19:dd:d9:dd:c25:c25:94de:294e
802c19:dd:d9:dd:c25:c25:94de:294f/1282c19:dd:d9:dd:c25:c25:94de:294f
812c19:dd:d9:dd:c25:c25:94de:2950/1282c19:dd:d9:dd:c25:c25:94de:2950
822c19:dd:d9:dd:c25:c25:94de:2951/1282c19:dd:d9:dd:c25:c25:94de:2951
832c19:dd:d9:dd:c25:c25:94de:2952/1282c19:dd:d9:dd:c25:c25:94de:2952
842c19:dd:d9:dd:c25:c25:94de:2953/1282c19:dd:d9:dd:c25:c25:94de:2953
852c19:dd:d9:dd:c25:c25:94de:2954/1282c19:dd:d9:dd:c25:c25:94de:2954
862c19:dd:d9:dd:c25:c25:94de:2955/1282c19:dd:d9:dd:c25:c25:94de:2955
872c19:dd:d9:dd:c25:c25:94de:2956/1282c19:dd:d9:dd:c25:c25:94de:2956
882c19:dd:d9:dd:c25:c25:94de:2957/1282c19:dd:d9:dd:c25:c25:94de:2957
892c19:dd:d9:dd:c25:c25:94de:2958/1282c19:dd:d9:dd:c25:c25:94de:2958
902c19:dd:d9:dd:c25:c25:94de:2959/1282c19:dd:d9:dd:c25:c25:94de:2959
912c19:dd:d9:dd:c25:c25:94de:295a/1282c19:dd:d9:dd:c25:c25:94de:295a
922c19:dd:d9:dd:c25:c25:94de:295b/1282c19:dd:d9:dd:c25:c25:94de:295b
932c19:dd:d9:dd:c25:c25:94de:295c/1282c19:dd:d9:dd:c25:c25:94de:295c
942c19:dd:d9:dd:c25:c25:94de:295d/1282c19:dd:d9:dd:c25:c25:94de:295d
952c19:dd:d9:dd:c25:c25:94de:295e/1282c19:dd:d9:dd:c25:c25:94de:295e
962c19:dd:d9:dd:c25:c25:94de:295f/1282c19:dd:d9:dd:c25:c25:94de:295f
972c19:dd:d9:dd:c25:c25:94de:2960/1282c19:dd:d9:dd:c25:c25:94de:2960
982c19:dd:d9:dd:c25:c25:94de:2961/1282c19:dd:d9:dd:c25:c25:94de:2961
992c19:dd:d9:dd:c25:c25:94de:2962/1282c19:dd:d9:dd:c25:c25:94de:2962
1002c19:dd:d9:dd:c25:c25:94de:2963/1282c19:dd:d9:dd:c25:c25:94de:2963
1012c19:dd:d9:dd:c25:c25:94de:2964/1282c19:dd:d9:dd:c25:c25:94de:2964
1022c19:dd:d9:dd:c25:c25:94de:2965/1282c19:dd:d9:dd:c25:c25:94de:2965
1032c19:dd:d9:dd:c25:c25:94de:2966/1282c19:dd:d9:dd:c25:c25:94de:2966
1042c19:dd:d9:dd:c25:c25:94de:2967/1282c19:dd:d9:dd:c25:c25:94de:2967
1052c19:dd:d9:dd:c25:c25:94de:2968/1282c19:dd:d9:dd:c25:c25:94de:2968
1062c19:dd:d9:dd:c25:c25:94de:2969/1282c19:dd:d9:dd:c25:c25:94de:2969
1072c19:dd:d9:dd:c25:c25:94de:296a/1282c19:dd:d9:dd:c25:c25:94de:296a
1082c19:dd:d9:dd:c25:c25:94de:296b/1282c19:dd:d9:dd:c25:c25:94de:296b
1092c19:dd:d9:dd:c25:c25:94de:296c/1282c19:dd:d9:dd:c25:c25:94de:296c
1102c19:dd:d9:dd:c25:c25:94de:296d/1282c19:dd:d9:dd:c25:c25:94de:296d
1112c19:dd:d9:dd:c25:c25:94de:296e/1282c19:dd:d9:dd:c25:c25:94de:296e
1122c19:dd:d9:dd:c25:c25:94de:296f/1282c19:dd:d9:dd:c25:c25:94de:296f
1132c19:dd:d9:dd:c25:c25:94de:2970/1282c19:dd:d9:dd:c25:c25:94de:2970
1142c19:dd:d9:dd:c25:c25:94de:2971/1282c19:dd:d9:dd:c25:c25:94de:2971
1152c19:dd:d9:dd:c25:c25:94de:2972/1282c19:dd:d9:dd:c25:c25:94de:2972
1162c19:dd:d9:dd:c25:c25:94de:2973/1282c19:dd:d9:dd:c25:c25:94de:2973
1172c19:dd:d9:dd:c25:c25:94de:2974/1282c19:dd:d9:dd:c25:c25:94de:2974
1182c19:dd:d9:dd:c25:c25:94de:2975/1282c19:dd:d9:dd:c25:c25:94de:2975
1192c19:dd:d9:dd:c25:c25:94de:2976/1282c19:dd:d9:dd:c25:c25:94de:2976
1202c19:dd:d9:dd:c25:c25:94de:2977/1282c19:dd:d9:dd:c25:c25:94de:2977
1212c19:dd:d9:dd:c25:c25:94de:2978/1282c19:dd:d9:dd:c25:c25:94de:2978
1222c19:dd:d9:dd:c25:c25:94de:2979/1282c19:dd:d9:dd:c25:c25:94de:2979
1232c19:dd:d9:dd:c25:c25:94de:297a/1282c19:dd:d9:dd:c25:c25:94de:297a
1242c19:dd:d9:dd:c25:c25:94de:297b/1282c19:dd:d9:dd:c25:c25:94de:297b
1252c19:dd:d9:dd:c25:c25:94de:297c/1282c19:dd:d9:dd:c25:c25:94de:297c
1262c19:dd:d9:dd:c25:c25:94de:297d/1282c19:dd:d9:dd:c25:c25:94de:297d
1272c19:dd:d9:dd:c25:c25:94de:297e/1282c19:dd:d9:dd:c25:c25:94de:297e
1282c19:dd:d9:dd:c25:c25:94de:297f/1282c19:dd:d9:dd:c25:c25:94de:297f
1292c19:dd:d9:dd:c25:c25:94de:2980/1282c19:dd:d9:dd:c25:c25:94de:2980
1302c19:dd:d9:dd:c25:c25:94de:2981/1282c19:dd:d9:dd:c25:c25:94de:2981
1312c19:dd:d9:dd:c25:c25:94de:2982/1282c19:dd:d9:dd:c25:c25:94de:2982
1322c19:dd:d9:dd:c25:c25:94de:2983/1282c19:dd:d9:dd:c25:c25:94de:2983
1332c19:dd:d9:dd:c25:c25:94de:2984/1282c19:dd:d9:dd:c25:c25:94de:2984
1342c19:dd:d9:dd:c25:c25:94de:2985/1282c19:dd:d9:dd:c25:c25:94de:2985
1352c19:dd:d9:dd:c25:c25:94de:2986/1282c19:dd:d9:dd:c25:c25:94de:2986
1362c19:dd:d9:dd:c25:c25:94de:2987/1282c19:dd:d9:dd:c25:c25:94de:2987
1372c19:dd:d9:dd:c25:c25:94de:2988/1282c19:dd:d9:dd:c25:c25:94de:2988
1382c19:dd:d9:dd:c25:c25:94de:2989/1282c19:dd:d9:dd:c25:c25:94de:2989
1392c19:dd:d9:dd:c25:c25:94de:298a/1282c19:dd:d9:dd:c25:c25:94de:298a
1402c19:dd:d9:dd:c25:c25:94de:298b/1282c19:dd:d9:dd:c25:c25:94de:298b
1412c19:dd:d9:dd:c25:c25:94de:298c/1282c19:dd:d9:dd:c25:c25:94de:298c
1422c19:dd:d9:dd:c25:c25:94de:298d/1282c19:dd:d9:dd:c25:c25:94de:298d
1432c19:dd:d9:dd:c25:c25:94de:298e/1282c19:dd:d9:dd:c25:c25:94de:298e
1442c19:dd:d9:dd:c25:c25:94de:298f/1282c19:dd:d9:dd:c25:c25:94de:298f
1452c19:dd:d9:dd:c25:c25:94de:2990/1282c19:dd:d9:dd:c25:c25:94de:2990
1462c19:dd:d9:dd:c25:c25:94de:2991/1282c19:dd:d9:dd:c25:c25:94de:2991
1472c19:dd:d9:dd:c25:c25:94de:2992/1282c19:dd:d9:dd:c25:c25:94de:2992
1482c19:dd:d9:dd:c25:c25:94de:2993/1282c19:dd:d9:dd:c25:c25:94de:2993
1492c19:dd:d9:dd:c25:c25:94de:2994/1282c19:dd:d9:dd:c25:c25:94de:2994
1502c19:dd:d9:dd:c25:c25:94de:2995/1282c19:dd:d9:dd:c25:c25:94de:2995
1512c19:dd:d9:dd:c25:c25:94de:2996/1282c19:dd:d9:dd:c25:c25:94de:2996
1522c19:dd:d9:dd:c25:c25:94de:2997/1282c19:dd:d9:dd:c25:c25:94de:2997
1532c19:dd:d9:dd:c25:c25:94de:2998/1282c19:dd:d9:dd:c25:c25:94de:2998
1542c19:dd:d9:dd:c25:c25:94de:2999/1282c19:dd:d9:dd:c25:c25:94de:2999
1552c19:dd:d9:dd:c25:c25:94de:299a/1282c19:dd:d9:dd:c25:c25:94de:299a
1562c19:dd:d9:dd:c25:c25:94de:299b/1282c19:dd:d9:dd:c25:c25:94de:299b
1572c19:dd:d9:dd:c25:c25:94de:299c/1282c19:dd:d9:dd:c25:c25:94de:299c
1582c19:dd:d9:dd:c25:c25:94de:299d/1282c19:dd:d9:dd:c25:c25:94de:299d
1592c19:dd:d9:dd:c25:c25:94de:299e/1282c19:dd:d9:dd:c25:c25:94de:299e
1602c19:dd:d9:dd:c25:c25:94de:299f/1282c19:dd:d9:dd:c25:c25:94de:299f
1612c19:dd:d9:dd:c25:c25:94de:29a0/1282c19:dd:d9:dd:c25:c25:94de:29a0
1622c19:dd:d9:dd:c25:c25:94de:29a1/1282c19:dd:d9:dd:c25:c25:94de:29a1
1632c19:dd:d9:dd:c25:c25:94de:29a2/1282c19:dd:d9:dd:c25:c25:94de:29a2
1642c19:dd:d9:dd:c25:c25:94de:29a3/1282c19:dd:d9:dd:c25:c25:94de:29a3
1652c19:dd:d9:dd:c25:c25:94de:29a4/1282c19:dd:d9:dd:c25:c25:94de:29a4
1662c19:dd:d9:dd:c25:c25:94de:29a5/1282c19:dd:d9:dd:c25:c25:94de:29a5
1672c19:dd:d9:dd:c25:c25:94de:29a6/1282c19:dd:d9:dd:c25:c25:94de:29a6
1682c19:dd:d9:dd:c25:c25:94de:29a7/1282c19:dd:d9:dd:c25:c25:94de:29a7
1692c19:dd:d9:dd:c25:c25:94de:29a8/1282c19:dd:d9:dd:c25:c25:94de:29a8
1702c19:dd:d9:dd:c25:c25:94de:29a9/1282c19:dd:d9:dd:c25:c25:94de:29a9
1712c19:dd:d9:dd:c25:c25:94de:29aa/1282c19:dd:d9:dd:c25:c25:94de:29aa
1722c19:dd:d9:dd:c25:c25:94de:29ab/1282c19:dd:d9:dd:c25:c25:94de:29ab
1732c19:dd:d9:dd:c25:c25:94de:29ac/1282c19:dd:d9:dd:c25:c25:94de:29ac
1742c19:dd:d9:dd:c25:c25:94de:29ad/1282c19:dd:d9:dd:c25:c25:94de:29ad
1752c19:dd:d9:dd:c25:c25:94de:29ae/1282c19:dd:d9:dd:c25:c25:94de:29ae
1762c19:dd:d9:dd:c25:c25:94de:29af/1282c19:dd:d9:dd:c25:c25:94de:29af
1772c19:dd:d9:dd:c25:c25:94de:29b0/1282c19:dd:d9:dd:c25:c25:94de:29b0
1782c19:dd:d9:dd:c25:c25:94de:29b1/1282c19:dd:d9:dd:c25:c25:94de:29b1
1792c19:dd:d9:dd:c25:c25:94de:29b2/1282c19:dd:d9:dd:c25:c25:94de:29b2
1802c19:dd:d9:dd:c25:c25:94de:29b3/1282c19:dd:d9:dd:c25:c25:94de:29b3
1812c19:dd:d9:dd:c25:c25:94de:29b4/1282c19:dd:d9:dd:c25:c25:94de:29b4
1822c19:dd:d9:dd:c25:c25:94de:29b5/1282c19:dd:d9:dd:c25:c25:94de:29b5
1832c19:dd:d9:dd:c25:c25:94de:29b6/1282c19:dd:d9:dd:c25:c25:94de:29b6
1842c19:dd:d9:dd:c25:c25:94de:29b7/1282c19:dd:d9:dd:c25:c25:94de:29b7
1852c19:dd:d9:dd:c25:c25:94de:29b8/1282c19:dd:d9:dd:c25:c25:94de:29b8
1862c19:dd:d9:dd:c25:c25:94de:29b9/1282c19:dd:d9:dd:c25:c25:94de:29b9
1872c19:dd:d9:dd:c25:c25:94de:29ba/1282c19:dd:d9:dd:c25:c25:94de:29ba
1882c19:dd:d9:dd:c25:c25:94de:29bb/1282c19:dd:d9:dd:c25:c25:94de:29bb
1892c19:dd:d9:dd:c25:c25:94de:29bc/1282c19:dd:d9:dd:c25:c25:94de:29bc
1902c19:dd:d9:dd:c25:c25:94de:29bd/1282c19:dd:d9:dd:c25:c25:94de:29bd
1912c19:dd:d9:dd:c25:c25:94de:29be/1282c19:dd:d9:dd:c25:c25:94de:29be
1922c19:dd:d9:dd:c25:c25:94de:29bf/1282c19:dd:d9:dd:c25:c25:94de:29bf
1932c19:dd:d9:dd:c25:c25:94de:29c0/1282c19:dd:d9:dd:c25:c25:94de:29c0
1942c19:dd:d9:dd:c25:c25:94de:29c1/1282c19:dd:d9:dd:c25:c25:94de:29c1
1952c19:dd:d9:dd:c25:c25:94de:29c2/1282c19:dd:d9:dd:c25:c25:94de:29c2
1962c19:dd:d9:dd:c25:c25:94de:29c3/1282c19:dd:d9:dd:c25:c25:94de:29c3
1972c19:dd:d9:dd:c25:c25:94de:29c4/1282c19:dd:d9:dd:c25:c25:94de:29c4
1982c19:dd:d9:dd:c25:c25:94de:29c5/1282c19:dd:d9:dd:c25:c25:94de:29c5
1992c19:dd:d9:dd:c25:c25:94de:29c6/1282c19:dd:d9:dd:c25:c25:94de:29c6
2002c19:dd:d9:dd:c25:c25:94de:29c7/1282c19:dd:d9:dd:c25:c25:94de:29c7
2012c19:dd:d9:dd:c25:c25:94de:29c8/1282c19:dd:d9:dd:c25:c25:94de:29c8
2022c19:dd:d9:dd:c25:c25:94de:29c9/1282c19:dd:d9:dd:c25:c25:94de:29c9
2032c19:dd:d9:dd:c25:c25:94de:29ca/1282c19:dd:d9:dd:c25:c25:94de:29ca
2042c19:dd:d9:dd:c25:c25:94de:29cb/1282c19:dd:d9:dd:c25:c25:94de:29cb
2052c19:dd:d9:dd:c25:c25:94de:29cc/1282c19:dd:d9:dd:c25:c25:94de:29cc
2062c19:dd:d9:dd:c25:c25:94de:29cd/1282c19:dd:d9:dd:c25:c25:94de:29cd
2072c19:dd:d9:dd:c25:c25:94de:29ce/1282c19:dd:d9:dd:c25:c25:94de:29ce
2082c19:dd:d9:dd:c25:c25:94de:29cf/1282c19:dd:d9:dd:c25:c25:94de:29cf
2092c19:dd:d9:dd:c25:c25:94de:29d0/1282c19:dd:d9:dd:c25:c25:94de:29d0
2102c19:dd:d9:dd:c25:c25:94de:29d1/1282c19:dd:d9:dd:c25:c25:94de:29d1
2112c19:dd:d9:dd:c25:c25:94de:29d2/1282c19:dd:d9:dd:c25:c25:94de:29d2
2122c19:dd:d9:dd:c25:c25:94de:29d3/1282c19:dd:d9:dd:c25:c25:94de:29d3
2132c19:dd:d9:dd:c25:c25:94de:29d4/1282c19:dd:d9:dd:c25:c25:94de:29d4
2142c19:dd:d9:dd:c25:c25:94de:29d5/1282c19:dd:d9:dd:c25:c25:94de:29d5
2152c19:dd:d9:dd:c25:c25:94de:29d6/1282c19:dd:d9:dd:c25:c25:94de:29d6
2162c19:dd:d9:dd:c25:c25:94de:29d7/1282c19:dd:d9:dd:c25:c25:94de:29d7
2172c19:dd:d9:dd:c25:c25:94de:29d8/1282c19:dd:d9:dd:c25:c25:94de:29d8
2182c19:dd:d9:dd:c25:c25:94de:29d9/1282c19:dd:d9:dd:c25:c25:94de:29d9
2192c19:dd:d9:dd:c25:c25:94de:29da/1282c19:dd:d9:dd:c25:c25:94de:29da
2202c19:dd:d9:dd:c25:c25:94de:29db/1282c19:dd:d9:dd:c25:c25:94de:29db
2212c19:dd:d9:dd:c25:c25:94de:29dc/1282c19:dd:d9:dd:c25:c25:94de:29dc
2222c19:dd:d9:dd:c25:c25:94de:29dd/1282c19:dd:d9:dd:c25:c25:94de:29dd
2232c19:dd:d9:dd:c25:c25:94de:29de/1282c19:dd:d9:dd:c25:c25:94de:29de
2242c19:dd:d9:dd:c25:c25:94de:29df/1282c19:dd:d9:dd:c25:c25:94de:29df
2252c19:dd:d9:dd:c25:c25:94de:29e0/1282c19:dd:d9:dd:c25:c25:94de:29e0
2262c19:dd:d9:dd:c25:c25:94de:29e1/1282c19:dd:d9:dd:c25:c25:94de:29e1
2272c19:dd:d9:dd:c25:c25:94de:29e2/1282c19:dd:d9:dd:c25:c25:94de:29e2
2282c19:dd:d9:dd:c25:c25:94de:29e3/1282c19:dd:d9:dd:c25:c25:94de:29e3
2292c19:dd:d9:dd:c25:c25:94de:29e4/1282c19:dd:d9:dd:c25:c25:94de:29e4
2302c19:dd:d9:dd:c25:c25:94de:29e5/1282c19:dd:d9:dd:c25:c25:94de:29e5
2312c19:dd:d9:dd:c25:c25:94de:29e6/1282c19:dd:d9:dd:c25:c25:94de:29e6
2322c19:dd:d9:dd:c25:c25:94de:29e7/1282c19:dd:d9:dd:c25:c25:94de:29e7
2332c19:dd:d9:dd:c25:c25:94de:29e8/1282c19:dd:d9:dd:c25:c25:94de:29e8
2342c19:dd:d9:dd:c25:c25:94de:29e9/1282c19:dd:d9:dd:c25:c25:94de:29e9
2352c19:dd:d9:dd:c25:c25:94de:29ea/1282c19:dd:d9:dd:c25:c25:94de:29ea
2362c19:dd:d9:dd:c25:c25:94de:29eb/1282c19:dd:d9:dd:c25:c25:94de:29eb
2372c19:dd:d9:dd:c25:c25:94de:29ec/1282c19:dd:d9:dd:c25:c25:94de:29ec
2382c19:dd:d9:dd:c25:c25:94de:29ed/1282c19:dd:d9:dd:c25:c25:94de:29ed
2392c19:dd:d9:dd:c25:c25:94de:29ee/1282c19:dd:d9:dd:c25:c25:94de:29ee
2402c19:dd:d9:dd:c25:c25:94de:29ef/1282c19:dd:d9:dd:c25:c25:94de:29ef
2412c19:dd:d9:dd:c25:c25:94de:29f0/1282c19:dd:d9:dd:c25:c25:94de:29f0
2422c19:dd:d9:dd:c25:c25:94de:29f1/1282c19:dd:d9:dd:c25:c25:94de:29f1
2432c19:dd:d9:dd:c25:c25:94de:29f2/1282c19:dd:d9:dd:c25:c25:94de:29f2
2442c19:dd:d9:dd:c25:c25:94de:29f3/1282c19:dd:d9:dd:c25:c25:94de:29f3
2452c19:dd:d9:dd:c25:c25:94de:29f4/1282c19:dd:d9:dd:c25:c25:94de:29f4
2462c19:dd:d9:dd:c25:c25:94de:29f5/1282c19:dd:d9:dd:c25:c25:94de:29f5
2472c19:dd:d9:dd:c25:c25:94de:29f6/1282c19:dd:d9:dd:c25:c25:94de:29f6
2482c19:dd:d9:dd:c25:c25:94de:29f7/1282c19:dd:d9:dd:c25:c25:94de:29f7
2492c19:dd:d9:dd:c25:c25:94de:29f8/1282c19:dd:d9:dd:c25:c25:94de:29f8
2502c19:dd:d9:dd:c25:c25:94de:29f9/1282c19:dd:d9:dd:c25:c25:94de:29f9
2512c19:dd:d9:dd:c25:c25:94de:29fa/1282c19:dd:d9:dd:c25:c25:94de:29fa
2522c19:dd:d9:dd:c25:c25:94de:29fb/1282c19:dd:d9:dd:c25:c25:94de:29fb
2532c19:dd:d9:dd:c25:c25:94de:29fc/1282c19:dd:d9:dd:c25:c25:94de:29fc
2542c19:dd:d9:dd:c25:c25:94de:29fd/1282c19:dd:d9:dd:c25:c25:94de:29fd
2552c19:dd:d9:dd:c25:c25:94de:29fe/1282c19:dd:d9:dd:c25:c25:94de:29fe
2562c19:dd:d9:dd:c25:c25:94de:29ff/1282c19:dd:d9:dd:c25:c25:94de:29ff

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.