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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/119
Addresses512
/64 networksPart of one
Network
2c19:dd:c25:c25:dd:dd:dd:2800/119
First address
2c19:dd:c25:c25:dd:dd:dd:2800
Last address
2c19:dd:c25:c25:dd:dd:dd:29ff
Addresses
512
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:0c25:00dd:00dd:00dd:2800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
8.2.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
9.2.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.0.d.d.0.0.9.1.c.2.ip6.arpa
/119 is not on a 4-bit boundary, so it takes 2 /120 zones.
Split into smaller subnets/128
/120 (2)/121 (4)/122 (8)/123 (16)/124 (32)/127 (256)/128 (512)

2c19:dd:c25:c25:dd:dd:dd:2800/119 makes 512 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:c25:c25:dd:dd:dd:2800/1282c19:dd:c25:c25:dd:dd:dd:2800
22c19:dd:c25:c25:dd:dd:dd:2801/1282c19:dd:c25:c25:dd:dd:dd:2801
32c19:dd:c25:c25:dd:dd:dd:2802/1282c19:dd:c25:c25:dd:dd:dd:2802
42c19:dd:c25:c25:dd:dd:dd:2803/1282c19:dd:c25:c25:dd:dd:dd:2803
52c19:dd:c25:c25:dd:dd:dd:2804/1282c19:dd:c25:c25:dd:dd:dd:2804
62c19:dd:c25:c25:dd:dd:dd:2805/1282c19:dd:c25:c25:dd:dd:dd:2805
72c19:dd:c25:c25:dd:dd:dd:2806/1282c19:dd:c25:c25:dd:dd:dd:2806
82c19:dd:c25:c25:dd:dd:dd:2807/1282c19:dd:c25:c25:dd:dd:dd:2807
92c19:dd:c25:c25:dd:dd:dd:2808/1282c19:dd:c25:c25:dd:dd:dd:2808
102c19:dd:c25:c25:dd:dd:dd:2809/1282c19:dd:c25:c25:dd:dd:dd:2809
112c19:dd:c25:c25:dd:dd:dd:280a/1282c19:dd:c25:c25:dd:dd:dd:280a
122c19:dd:c25:c25:dd:dd:dd:280b/1282c19:dd:c25:c25:dd:dd:dd:280b
132c19:dd:c25:c25:dd:dd:dd:280c/1282c19:dd:c25:c25:dd:dd:dd:280c
142c19:dd:c25:c25:dd:dd:dd:280d/1282c19:dd:c25:c25:dd:dd:dd:280d
152c19:dd:c25:c25:dd:dd:dd:280e/1282c19:dd:c25:c25:dd:dd:dd:280e
162c19:dd:c25:c25:dd:dd:dd:280f/1282c19:dd:c25:c25:dd:dd:dd:280f
172c19:dd:c25:c25:dd:dd:dd:2810/1282c19:dd:c25:c25:dd:dd:dd:2810
182c19:dd:c25:c25:dd:dd:dd:2811/1282c19:dd:c25:c25:dd:dd:dd:2811
192c19:dd:c25:c25:dd:dd:dd:2812/1282c19:dd:c25:c25:dd:dd:dd:2812
202c19:dd:c25:c25:dd:dd:dd:2813/1282c19:dd:c25:c25:dd:dd:dd:2813
212c19:dd:c25:c25:dd:dd:dd:2814/1282c19:dd:c25:c25:dd:dd:dd:2814
222c19:dd:c25:c25:dd:dd:dd:2815/1282c19:dd:c25:c25:dd:dd:dd:2815
232c19:dd:c25:c25:dd:dd:dd:2816/1282c19:dd:c25:c25:dd:dd:dd:2816
242c19:dd:c25:c25:dd:dd:dd:2817/1282c19:dd:c25:c25:dd:dd:dd:2817
252c19:dd:c25:c25:dd:dd:dd:2818/1282c19:dd:c25:c25:dd:dd:dd:2818
262c19:dd:c25:c25:dd:dd:dd:2819/1282c19:dd:c25:c25:dd:dd:dd:2819
272c19:dd:c25:c25:dd:dd:dd:281a/1282c19:dd:c25:c25:dd:dd:dd:281a
282c19:dd:c25:c25:dd:dd:dd:281b/1282c19:dd:c25:c25:dd:dd:dd:281b
292c19:dd:c25:c25:dd:dd:dd:281c/1282c19:dd:c25:c25:dd:dd:dd:281c
302c19:dd:c25:c25:dd:dd:dd:281d/1282c19:dd:c25:c25:dd:dd:dd:281d
312c19:dd:c25:c25:dd:dd:dd:281e/1282c19:dd:c25:c25:dd:dd:dd:281e
322c19:dd:c25:c25:dd:dd:dd:281f/1282c19:dd:c25:c25:dd:dd:dd:281f
332c19:dd:c25:c25:dd:dd:dd:2820/1282c19:dd:c25:c25:dd:dd:dd:2820
342c19:dd:c25:c25:dd:dd:dd:2821/1282c19:dd:c25:c25:dd:dd:dd:2821
352c19:dd:c25:c25:dd:dd:dd:2822/1282c19:dd:c25:c25:dd:dd:dd:2822
362c19:dd:c25:c25:dd:dd:dd:2823/1282c19:dd:c25:c25:dd:dd:dd:2823
372c19:dd:c25:c25:dd:dd:dd:2824/1282c19:dd:c25:c25:dd:dd:dd:2824
382c19:dd:c25:c25:dd:dd:dd:2825/1282c19:dd:c25:c25:dd:dd:dd:2825
392c19:dd:c25:c25:dd:dd:dd:2826/1282c19:dd:c25:c25:dd:dd:dd:2826
402c19:dd:c25:c25:dd:dd:dd:2827/1282c19:dd:c25:c25:dd:dd:dd:2827
412c19:dd:c25:c25:dd:dd:dd:2828/1282c19:dd:c25:c25:dd:dd:dd:2828
422c19:dd:c25:c25:dd:dd:dd:2829/1282c19:dd:c25:c25:dd:dd:dd:2829
432c19:dd:c25:c25:dd:dd:dd:282a/1282c19:dd:c25:c25:dd:dd:dd:282a
442c19:dd:c25:c25:dd:dd:dd:282b/1282c19:dd:c25:c25:dd:dd:dd:282b
452c19:dd:c25:c25:dd:dd:dd:282c/1282c19:dd:c25:c25:dd:dd:dd:282c
462c19:dd:c25:c25:dd:dd:dd:282d/1282c19:dd:c25:c25:dd:dd:dd:282d
472c19:dd:c25:c25:dd:dd:dd:282e/1282c19:dd:c25:c25:dd:dd:dd:282e
482c19:dd:c25:c25:dd:dd:dd:282f/1282c19:dd:c25:c25:dd:dd:dd:282f
492c19:dd:c25:c25:dd:dd:dd:2830/1282c19:dd:c25:c25:dd:dd:dd:2830
502c19:dd:c25:c25:dd:dd:dd:2831/1282c19:dd:c25:c25:dd:dd:dd:2831
512c19:dd:c25:c25:dd:dd:dd:2832/1282c19:dd:c25:c25:dd:dd:dd:2832
522c19:dd:c25:c25:dd:dd:dd:2833/1282c19:dd:c25:c25:dd:dd:dd:2833
532c19:dd:c25:c25:dd:dd:dd:2834/1282c19:dd:c25:c25:dd:dd:dd:2834
542c19:dd:c25:c25:dd:dd:dd:2835/1282c19:dd:c25:c25:dd:dd:dd:2835
552c19:dd:c25:c25:dd:dd:dd:2836/1282c19:dd:c25:c25:dd:dd:dd:2836
562c19:dd:c25:c25:dd:dd:dd:2837/1282c19:dd:c25:c25:dd:dd:dd:2837
572c19:dd:c25:c25:dd:dd:dd:2838/1282c19:dd:c25:c25:dd:dd:dd:2838
582c19:dd:c25:c25:dd:dd:dd:2839/1282c19:dd:c25:c25:dd:dd:dd:2839
592c19:dd:c25:c25:dd:dd:dd:283a/1282c19:dd:c25:c25:dd:dd:dd:283a
602c19:dd:c25:c25:dd:dd:dd:283b/1282c19:dd:c25:c25:dd:dd:dd:283b
612c19:dd:c25:c25:dd:dd:dd:283c/1282c19:dd:c25:c25:dd:dd:dd:283c
622c19:dd:c25:c25:dd:dd:dd:283d/1282c19:dd:c25:c25:dd:dd:dd:283d
632c19:dd:c25:c25:dd:dd:dd:283e/1282c19:dd:c25:c25:dd:dd:dd:283e
642c19:dd:c25:c25:dd:dd:dd:283f/1282c19:dd:c25:c25:dd:dd:dd:283f
652c19:dd:c25:c25:dd:dd:dd:2840/1282c19:dd:c25:c25:dd:dd:dd:2840
662c19:dd:c25:c25:dd:dd:dd:2841/1282c19:dd:c25:c25:dd:dd:dd:2841
672c19:dd:c25:c25:dd:dd:dd:2842/1282c19:dd:c25:c25:dd:dd:dd:2842
682c19:dd:c25:c25:dd:dd:dd:2843/1282c19:dd:c25:c25:dd:dd:dd:2843
692c19:dd:c25:c25:dd:dd:dd:2844/1282c19:dd:c25:c25:dd:dd:dd:2844
702c19:dd:c25:c25:dd:dd:dd:2845/1282c19:dd:c25:c25:dd:dd:dd:2845
712c19:dd:c25:c25:dd:dd:dd:2846/1282c19:dd:c25:c25:dd:dd:dd:2846
722c19:dd:c25:c25:dd:dd:dd:2847/1282c19:dd:c25:c25:dd:dd:dd:2847
732c19:dd:c25:c25:dd:dd:dd:2848/1282c19:dd:c25:c25:dd:dd:dd:2848
742c19:dd:c25:c25:dd:dd:dd:2849/1282c19:dd:c25:c25:dd:dd:dd:2849
752c19:dd:c25:c25:dd:dd:dd:284a/1282c19:dd:c25:c25:dd:dd:dd:284a
762c19:dd:c25:c25:dd:dd:dd:284b/1282c19:dd:c25:c25:dd:dd:dd:284b
772c19:dd:c25:c25:dd:dd:dd:284c/1282c19:dd:c25:c25:dd:dd:dd:284c
782c19:dd:c25:c25:dd:dd:dd:284d/1282c19:dd:c25:c25:dd:dd:dd:284d
792c19:dd:c25:c25:dd:dd:dd:284e/1282c19:dd:c25:c25:dd:dd:dd:284e
802c19:dd:c25:c25:dd:dd:dd:284f/1282c19:dd:c25:c25:dd:dd:dd:284f
812c19:dd:c25:c25:dd:dd:dd:2850/1282c19:dd:c25:c25:dd:dd:dd:2850
822c19:dd:c25:c25:dd:dd:dd:2851/1282c19:dd:c25:c25:dd:dd:dd:2851
832c19:dd:c25:c25:dd:dd:dd:2852/1282c19:dd:c25:c25:dd:dd:dd:2852
842c19:dd:c25:c25:dd:dd:dd:2853/1282c19:dd:c25:c25:dd:dd:dd:2853
852c19:dd:c25:c25:dd:dd:dd:2854/1282c19:dd:c25:c25:dd:dd:dd:2854
862c19:dd:c25:c25:dd:dd:dd:2855/1282c19:dd:c25:c25:dd:dd:dd:2855
872c19:dd:c25:c25:dd:dd:dd:2856/1282c19:dd:c25:c25:dd:dd:dd:2856
882c19:dd:c25:c25:dd:dd:dd:2857/1282c19:dd:c25:c25:dd:dd:dd:2857
892c19:dd:c25:c25:dd:dd:dd:2858/1282c19:dd:c25:c25:dd:dd:dd:2858
902c19:dd:c25:c25:dd:dd:dd:2859/1282c19:dd:c25:c25:dd:dd:dd:2859
912c19:dd:c25:c25:dd:dd:dd:285a/1282c19:dd:c25:c25:dd:dd:dd:285a
922c19:dd:c25:c25:dd:dd:dd:285b/1282c19:dd:c25:c25:dd:dd:dd:285b
932c19:dd:c25:c25:dd:dd:dd:285c/1282c19:dd:c25:c25:dd:dd:dd:285c
942c19:dd:c25:c25:dd:dd:dd:285d/1282c19:dd:c25:c25:dd:dd:dd:285d
952c19:dd:c25:c25:dd:dd:dd:285e/1282c19:dd:c25:c25:dd:dd:dd:285e
962c19:dd:c25:c25:dd:dd:dd:285f/1282c19:dd:c25:c25:dd:dd:dd:285f
972c19:dd:c25:c25:dd:dd:dd:2860/1282c19:dd:c25:c25:dd:dd:dd:2860
982c19:dd:c25:c25:dd:dd:dd:2861/1282c19:dd:c25:c25:dd:dd:dd:2861
992c19:dd:c25:c25:dd:dd:dd:2862/1282c19:dd:c25:c25:dd:dd:dd:2862
1002c19:dd:c25:c25:dd:dd:dd:2863/1282c19:dd:c25:c25:dd:dd:dd:2863
1012c19:dd:c25:c25:dd:dd:dd:2864/1282c19:dd:c25:c25:dd:dd:dd:2864
1022c19:dd:c25:c25:dd:dd:dd:2865/1282c19:dd:c25:c25:dd:dd:dd:2865
1032c19:dd:c25:c25:dd:dd:dd:2866/1282c19:dd:c25:c25:dd:dd:dd:2866
1042c19:dd:c25:c25:dd:dd:dd:2867/1282c19:dd:c25:c25:dd:dd:dd:2867
1052c19:dd:c25:c25:dd:dd:dd:2868/1282c19:dd:c25:c25:dd:dd:dd:2868
1062c19:dd:c25:c25:dd:dd:dd:2869/1282c19:dd:c25:c25:dd:dd:dd:2869
1072c19:dd:c25:c25:dd:dd:dd:286a/1282c19:dd:c25:c25:dd:dd:dd:286a
1082c19:dd:c25:c25:dd:dd:dd:286b/1282c19:dd:c25:c25:dd:dd:dd:286b
1092c19:dd:c25:c25:dd:dd:dd:286c/1282c19:dd:c25:c25:dd:dd:dd:286c
1102c19:dd:c25:c25:dd:dd:dd:286d/1282c19:dd:c25:c25:dd:dd:dd:286d
1112c19:dd:c25:c25:dd:dd:dd:286e/1282c19:dd:c25:c25:dd:dd:dd:286e
1122c19:dd:c25:c25:dd:dd:dd:286f/1282c19:dd:c25:c25:dd:dd:dd:286f
1132c19:dd:c25:c25:dd:dd:dd:2870/1282c19:dd:c25:c25:dd:dd:dd:2870
1142c19:dd:c25:c25:dd:dd:dd:2871/1282c19:dd:c25:c25:dd:dd:dd:2871
1152c19:dd:c25:c25:dd:dd:dd:2872/1282c19:dd:c25:c25:dd:dd:dd:2872
1162c19:dd:c25:c25:dd:dd:dd:2873/1282c19:dd:c25:c25:dd:dd:dd:2873
1172c19:dd:c25:c25:dd:dd:dd:2874/1282c19:dd:c25:c25:dd:dd:dd:2874
1182c19:dd:c25:c25:dd:dd:dd:2875/1282c19:dd:c25:c25:dd:dd:dd:2875
1192c19:dd:c25:c25:dd:dd:dd:2876/1282c19:dd:c25:c25:dd:dd:dd:2876
1202c19:dd:c25:c25:dd:dd:dd:2877/1282c19:dd:c25:c25:dd:dd:dd:2877
1212c19:dd:c25:c25:dd:dd:dd:2878/1282c19:dd:c25:c25:dd:dd:dd:2878
1222c19:dd:c25:c25:dd:dd:dd:2879/1282c19:dd:c25:c25:dd:dd:dd:2879
1232c19:dd:c25:c25:dd:dd:dd:287a/1282c19:dd:c25:c25:dd:dd:dd:287a
1242c19:dd:c25:c25:dd:dd:dd:287b/1282c19:dd:c25:c25:dd:dd:dd:287b
1252c19:dd:c25:c25:dd:dd:dd:287c/1282c19:dd:c25:c25:dd:dd:dd:287c
1262c19:dd:c25:c25:dd:dd:dd:287d/1282c19:dd:c25:c25:dd:dd:dd:287d
1272c19:dd:c25:c25:dd:dd:dd:287e/1282c19:dd:c25:c25:dd:dd:dd:287e
1282c19:dd:c25:c25:dd:dd:dd:287f/1282c19:dd:c25:c25:dd:dd:dd:287f
1292c19:dd:c25:c25:dd:dd:dd:2880/1282c19:dd:c25:c25:dd:dd:dd:2880
1302c19:dd:c25:c25:dd:dd:dd:2881/1282c19:dd:c25:c25:dd:dd:dd:2881
1312c19:dd:c25:c25:dd:dd:dd:2882/1282c19:dd:c25:c25:dd:dd:dd:2882
1322c19:dd:c25:c25:dd:dd:dd:2883/1282c19:dd:c25:c25:dd:dd:dd:2883
1332c19:dd:c25:c25:dd:dd:dd:2884/1282c19:dd:c25:c25:dd:dd:dd:2884
1342c19:dd:c25:c25:dd:dd:dd:2885/1282c19:dd:c25:c25:dd:dd:dd:2885
1352c19:dd:c25:c25:dd:dd:dd:2886/1282c19:dd:c25:c25:dd:dd:dd:2886
1362c19:dd:c25:c25:dd:dd:dd:2887/1282c19:dd:c25:c25:dd:dd:dd:2887
1372c19:dd:c25:c25:dd:dd:dd:2888/1282c19:dd:c25:c25:dd:dd:dd:2888
1382c19:dd:c25:c25:dd:dd:dd:2889/1282c19:dd:c25:c25:dd:dd:dd:2889
1392c19:dd:c25:c25:dd:dd:dd:288a/1282c19:dd:c25:c25:dd:dd:dd:288a
1402c19:dd:c25:c25:dd:dd:dd:288b/1282c19:dd:c25:c25:dd:dd:dd:288b
1412c19:dd:c25:c25:dd:dd:dd:288c/1282c19:dd:c25:c25:dd:dd:dd:288c
1422c19:dd:c25:c25:dd:dd:dd:288d/1282c19:dd:c25:c25:dd:dd:dd:288d
1432c19:dd:c25:c25:dd:dd:dd:288e/1282c19:dd:c25:c25:dd:dd:dd:288e
1442c19:dd:c25:c25:dd:dd:dd:288f/1282c19:dd:c25:c25:dd:dd:dd:288f
1452c19:dd:c25:c25:dd:dd:dd:2890/1282c19:dd:c25:c25:dd:dd:dd:2890
1462c19:dd:c25:c25:dd:dd:dd:2891/1282c19:dd:c25:c25:dd:dd:dd:2891
1472c19:dd:c25:c25:dd:dd:dd:2892/1282c19:dd:c25:c25:dd:dd:dd:2892
1482c19:dd:c25:c25:dd:dd:dd:2893/1282c19:dd:c25:c25:dd:dd:dd:2893
1492c19:dd:c25:c25:dd:dd:dd:2894/1282c19:dd:c25:c25:dd:dd:dd:2894
1502c19:dd:c25:c25:dd:dd:dd:2895/1282c19:dd:c25:c25:dd:dd:dd:2895
1512c19:dd:c25:c25:dd:dd:dd:2896/1282c19:dd:c25:c25:dd:dd:dd:2896
1522c19:dd:c25:c25:dd:dd:dd:2897/1282c19:dd:c25:c25:dd:dd:dd:2897
1532c19:dd:c25:c25:dd:dd:dd:2898/1282c19:dd:c25:c25:dd:dd:dd:2898
1542c19:dd:c25:c25:dd:dd:dd:2899/1282c19:dd:c25:c25:dd:dd:dd:2899
1552c19:dd:c25:c25:dd:dd:dd:289a/1282c19:dd:c25:c25:dd:dd:dd:289a
1562c19:dd:c25:c25:dd:dd:dd:289b/1282c19:dd:c25:c25:dd:dd:dd:289b
1572c19:dd:c25:c25:dd:dd:dd:289c/1282c19:dd:c25:c25:dd:dd:dd:289c
1582c19:dd:c25:c25:dd:dd:dd:289d/1282c19:dd:c25:c25:dd:dd:dd:289d
1592c19:dd:c25:c25:dd:dd:dd:289e/1282c19:dd:c25:c25:dd:dd:dd:289e
1602c19:dd:c25:c25:dd:dd:dd:289f/1282c19:dd:c25:c25:dd:dd:dd:289f
1612c19:dd:c25:c25:dd:dd:dd:28a0/1282c19:dd:c25:c25:dd:dd:dd:28a0
1622c19:dd:c25:c25:dd:dd:dd:28a1/1282c19:dd:c25:c25:dd:dd:dd:28a1
1632c19:dd:c25:c25:dd:dd:dd:28a2/1282c19:dd:c25:c25:dd:dd:dd:28a2
1642c19:dd:c25:c25:dd:dd:dd:28a3/1282c19:dd:c25:c25:dd:dd:dd:28a3
1652c19:dd:c25:c25:dd:dd:dd:28a4/1282c19:dd:c25:c25:dd:dd:dd:28a4
1662c19:dd:c25:c25:dd:dd:dd:28a5/1282c19:dd:c25:c25:dd:dd:dd:28a5
1672c19:dd:c25:c25:dd:dd:dd:28a6/1282c19:dd:c25:c25:dd:dd:dd:28a6
1682c19:dd:c25:c25:dd:dd:dd:28a7/1282c19:dd:c25:c25:dd:dd:dd:28a7
1692c19:dd:c25:c25:dd:dd:dd:28a8/1282c19:dd:c25:c25:dd:dd:dd:28a8
1702c19:dd:c25:c25:dd:dd:dd:28a9/1282c19:dd:c25:c25:dd:dd:dd:28a9
1712c19:dd:c25:c25:dd:dd:dd:28aa/1282c19:dd:c25:c25:dd:dd:dd:28aa
1722c19:dd:c25:c25:dd:dd:dd:28ab/1282c19:dd:c25:c25:dd:dd:dd:28ab
1732c19:dd:c25:c25:dd:dd:dd:28ac/1282c19:dd:c25:c25:dd:dd:dd:28ac
1742c19:dd:c25:c25:dd:dd:dd:28ad/1282c19:dd:c25:c25:dd:dd:dd:28ad
1752c19:dd:c25:c25:dd:dd:dd:28ae/1282c19:dd:c25:c25:dd:dd:dd:28ae
1762c19:dd:c25:c25:dd:dd:dd:28af/1282c19:dd:c25:c25:dd:dd:dd:28af
1772c19:dd:c25:c25:dd:dd:dd:28b0/1282c19:dd:c25:c25:dd:dd:dd:28b0
1782c19:dd:c25:c25:dd:dd:dd:28b1/1282c19:dd:c25:c25:dd:dd:dd:28b1
1792c19:dd:c25:c25:dd:dd:dd:28b2/1282c19:dd:c25:c25:dd:dd:dd:28b2
1802c19:dd:c25:c25:dd:dd:dd:28b3/1282c19:dd:c25:c25:dd:dd:dd:28b3
1812c19:dd:c25:c25:dd:dd:dd:28b4/1282c19:dd:c25:c25:dd:dd:dd:28b4
1822c19:dd:c25:c25:dd:dd:dd:28b5/1282c19:dd:c25:c25:dd:dd:dd:28b5
1832c19:dd:c25:c25:dd:dd:dd:28b6/1282c19:dd:c25:c25:dd:dd:dd:28b6
1842c19:dd:c25:c25:dd:dd:dd:28b7/1282c19:dd:c25:c25:dd:dd:dd:28b7
1852c19:dd:c25:c25:dd:dd:dd:28b8/1282c19:dd:c25:c25:dd:dd:dd:28b8
1862c19:dd:c25:c25:dd:dd:dd:28b9/1282c19:dd:c25:c25:dd:dd:dd:28b9
1872c19:dd:c25:c25:dd:dd:dd:28ba/1282c19:dd:c25:c25:dd:dd:dd:28ba
1882c19:dd:c25:c25:dd:dd:dd:28bb/1282c19:dd:c25:c25:dd:dd:dd:28bb
1892c19:dd:c25:c25:dd:dd:dd:28bc/1282c19:dd:c25:c25:dd:dd:dd:28bc
1902c19:dd:c25:c25:dd:dd:dd:28bd/1282c19:dd:c25:c25:dd:dd:dd:28bd
1912c19:dd:c25:c25:dd:dd:dd:28be/1282c19:dd:c25:c25:dd:dd:dd:28be
1922c19:dd:c25:c25:dd:dd:dd:28bf/1282c19:dd:c25:c25:dd:dd:dd:28bf
1932c19:dd:c25:c25:dd:dd:dd:28c0/1282c19:dd:c25:c25:dd:dd:dd:28c0
1942c19:dd:c25:c25:dd:dd:dd:28c1/1282c19:dd:c25:c25:dd:dd:dd:28c1
1952c19:dd:c25:c25:dd:dd:dd:28c2/1282c19:dd:c25:c25:dd:dd:dd:28c2
1962c19:dd:c25:c25:dd:dd:dd:28c3/1282c19:dd:c25:c25:dd:dd:dd:28c3
1972c19:dd:c25:c25:dd:dd:dd:28c4/1282c19:dd:c25:c25:dd:dd:dd:28c4
1982c19:dd:c25:c25:dd:dd:dd:28c5/1282c19:dd:c25:c25:dd:dd:dd:28c5
1992c19:dd:c25:c25:dd:dd:dd:28c6/1282c19:dd:c25:c25:dd:dd:dd:28c6
2002c19:dd:c25:c25:dd:dd:dd:28c7/1282c19:dd:c25:c25:dd:dd:dd:28c7
2012c19:dd:c25:c25:dd:dd:dd:28c8/1282c19:dd:c25:c25:dd:dd:dd:28c8
2022c19:dd:c25:c25:dd:dd:dd:28c9/1282c19:dd:c25:c25:dd:dd:dd:28c9
2032c19:dd:c25:c25:dd:dd:dd:28ca/1282c19:dd:c25:c25:dd:dd:dd:28ca
2042c19:dd:c25:c25:dd:dd:dd:28cb/1282c19:dd:c25:c25:dd:dd:dd:28cb
2052c19:dd:c25:c25:dd:dd:dd:28cc/1282c19:dd:c25:c25:dd:dd:dd:28cc
2062c19:dd:c25:c25:dd:dd:dd:28cd/1282c19:dd:c25:c25:dd:dd:dd:28cd
2072c19:dd:c25:c25:dd:dd:dd:28ce/1282c19:dd:c25:c25:dd:dd:dd:28ce
2082c19:dd:c25:c25:dd:dd:dd:28cf/1282c19:dd:c25:c25:dd:dd:dd:28cf
2092c19:dd:c25:c25:dd:dd:dd:28d0/1282c19:dd:c25:c25:dd:dd:dd:28d0
2102c19:dd:c25:c25:dd:dd:dd:28d1/1282c19:dd:c25:c25:dd:dd:dd:28d1
2112c19:dd:c25:c25:dd:dd:dd:28d2/1282c19:dd:c25:c25:dd:dd:dd:28d2
2122c19:dd:c25:c25:dd:dd:dd:28d3/1282c19:dd:c25:c25:dd:dd:dd:28d3
2132c19:dd:c25:c25:dd:dd:dd:28d4/1282c19:dd:c25:c25:dd:dd:dd:28d4
2142c19:dd:c25:c25:dd:dd:dd:28d5/1282c19:dd:c25:c25:dd:dd:dd:28d5
2152c19:dd:c25:c25:dd:dd:dd:28d6/1282c19:dd:c25:c25:dd:dd:dd:28d6
2162c19:dd:c25:c25:dd:dd:dd:28d7/1282c19:dd:c25:c25:dd:dd:dd:28d7
2172c19:dd:c25:c25:dd:dd:dd:28d8/1282c19:dd:c25:c25:dd:dd:dd:28d8
2182c19:dd:c25:c25:dd:dd:dd:28d9/1282c19:dd:c25:c25:dd:dd:dd:28d9
2192c19:dd:c25:c25:dd:dd:dd:28da/1282c19:dd:c25:c25:dd:dd:dd:28da
2202c19:dd:c25:c25:dd:dd:dd:28db/1282c19:dd:c25:c25:dd:dd:dd:28db
2212c19:dd:c25:c25:dd:dd:dd:28dc/1282c19:dd:c25:c25:dd:dd:dd:28dc
2222c19:dd:c25:c25:dd:dd:dd:28dd/1282c19:dd:c25:c25:dd:dd:dd:28dd
2232c19:dd:c25:c25:dd:dd:dd:28de/1282c19:dd:c25:c25:dd:dd:dd:28de
2242c19:dd:c25:c25:dd:dd:dd:28df/1282c19:dd:c25:c25:dd:dd:dd:28df
2252c19:dd:c25:c25:dd:dd:dd:28e0/1282c19:dd:c25:c25:dd:dd:dd:28e0
2262c19:dd:c25:c25:dd:dd:dd:28e1/1282c19:dd:c25:c25:dd:dd:dd:28e1
2272c19:dd:c25:c25:dd:dd:dd:28e2/1282c19:dd:c25:c25:dd:dd:dd:28e2
2282c19:dd:c25:c25:dd:dd:dd:28e3/1282c19:dd:c25:c25:dd:dd:dd:28e3
2292c19:dd:c25:c25:dd:dd:dd:28e4/1282c19:dd:c25:c25:dd:dd:dd:28e4
2302c19:dd:c25:c25:dd:dd:dd:28e5/1282c19:dd:c25:c25:dd:dd:dd:28e5
2312c19:dd:c25:c25:dd:dd:dd:28e6/1282c19:dd:c25:c25:dd:dd:dd:28e6
2322c19:dd:c25:c25:dd:dd:dd:28e7/1282c19:dd:c25:c25:dd:dd:dd:28e7
2332c19:dd:c25:c25:dd:dd:dd:28e8/1282c19:dd:c25:c25:dd:dd:dd:28e8
2342c19:dd:c25:c25:dd:dd:dd:28e9/1282c19:dd:c25:c25:dd:dd:dd:28e9
2352c19:dd:c25:c25:dd:dd:dd:28ea/1282c19:dd:c25:c25:dd:dd:dd:28ea
2362c19:dd:c25:c25:dd:dd:dd:28eb/1282c19:dd:c25:c25:dd:dd:dd:28eb
2372c19:dd:c25:c25:dd:dd:dd:28ec/1282c19:dd:c25:c25:dd:dd:dd:28ec
2382c19:dd:c25:c25:dd:dd:dd:28ed/1282c19:dd:c25:c25:dd:dd:dd:28ed
2392c19:dd:c25:c25:dd:dd:dd:28ee/1282c19:dd:c25:c25:dd:dd:dd:28ee
2402c19:dd:c25:c25:dd:dd:dd:28ef/1282c19:dd:c25:c25:dd:dd:dd:28ef
2412c19:dd:c25:c25:dd:dd:dd:28f0/1282c19:dd:c25:c25:dd:dd:dd:28f0
2422c19:dd:c25:c25:dd:dd:dd:28f1/1282c19:dd:c25:c25:dd:dd:dd:28f1
2432c19:dd:c25:c25:dd:dd:dd:28f2/1282c19:dd:c25:c25:dd:dd:dd:28f2
2442c19:dd:c25:c25:dd:dd:dd:28f3/1282c19:dd:c25:c25:dd:dd:dd:28f3
2452c19:dd:c25:c25:dd:dd:dd:28f4/1282c19:dd:c25:c25:dd:dd:dd:28f4
2462c19:dd:c25:c25:dd:dd:dd:28f5/1282c19:dd:c25:c25:dd:dd:dd:28f5
2472c19:dd:c25:c25:dd:dd:dd:28f6/1282c19:dd:c25:c25:dd:dd:dd:28f6
2482c19:dd:c25:c25:dd:dd:dd:28f7/1282c19:dd:c25:c25:dd:dd:dd:28f7
2492c19:dd:c25:c25:dd:dd:dd:28f8/1282c19:dd:c25:c25:dd:dd:dd:28f8
2502c19:dd:c25:c25:dd:dd:dd:28f9/1282c19:dd:c25:c25:dd:dd:dd:28f9
2512c19:dd:c25:c25:dd:dd:dd:28fa/1282c19:dd:c25:c25:dd:dd:dd:28fa
2522c19:dd:c25:c25:dd:dd:dd:28fb/1282c19:dd:c25:c25:dd:dd:dd:28fb
2532c19:dd:c25:c25:dd:dd:dd:28fc/1282c19:dd:c25:c25:dd:dd:dd:28fc
2542c19:dd:c25:c25:dd:dd:dd:28fd/1282c19:dd:c25:c25:dd:dd:dd:28fd
2552c19:dd:c25:c25:dd:dd:dd:28fe/1282c19:dd:c25:c25:dd:dd:dd:28fe
2562c19:dd:c25:c25:dd:dd:dd:28ff/1282c19:dd:c25:c25:dd:dd:dd:28ff

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.