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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:d9:dd:c25:c25:94de:9800/117
First address
2c19:dd:d9:dd:c25:c25:94de:9800
Last address
2c19:dd:d9:dd:c25:c25:94de:9fff
Addresses
2,048
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:9800
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zones
8.9.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
9.9.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
a.9.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
b.9.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
c.9.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
d.9.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
e.9.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
f.9.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
/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:d9:dd:c25:c25:94de:9800/117 makes 2,048 subnets of /128; the first 256 are listed.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:9800/1282c19:dd:d9:dd:c25:c25:94de:9800
22c19:dd:d9:dd:c25:c25:94de:9801/1282c19:dd:d9:dd:c25:c25:94de:9801
32c19:dd:d9:dd:c25:c25:94de:9802/1282c19:dd:d9:dd:c25:c25:94de:9802
42c19:dd:d9:dd:c25:c25:94de:9803/1282c19:dd:d9:dd:c25:c25:94de:9803
52c19:dd:d9:dd:c25:c25:94de:9804/1282c19:dd:d9:dd:c25:c25:94de:9804
62c19:dd:d9:dd:c25:c25:94de:9805/1282c19:dd:d9:dd:c25:c25:94de:9805
72c19:dd:d9:dd:c25:c25:94de:9806/1282c19:dd:d9:dd:c25:c25:94de:9806
82c19:dd:d9:dd:c25:c25:94de:9807/1282c19:dd:d9:dd:c25:c25:94de:9807
92c19:dd:d9:dd:c25:c25:94de:9808/1282c19:dd:d9:dd:c25:c25:94de:9808
102c19:dd:d9:dd:c25:c25:94de:9809/1282c19:dd:d9:dd:c25:c25:94de:9809
112c19:dd:d9:dd:c25:c25:94de:980a/1282c19:dd:d9:dd:c25:c25:94de:980a
122c19:dd:d9:dd:c25:c25:94de:980b/1282c19:dd:d9:dd:c25:c25:94de:980b
132c19:dd:d9:dd:c25:c25:94de:980c/1282c19:dd:d9:dd:c25:c25:94de:980c
142c19:dd:d9:dd:c25:c25:94de:980d/1282c19:dd:d9:dd:c25:c25:94de:980d
152c19:dd:d9:dd:c25:c25:94de:980e/1282c19:dd:d9:dd:c25:c25:94de:980e
162c19:dd:d9:dd:c25:c25:94de:980f/1282c19:dd:d9:dd:c25:c25:94de:980f
172c19:dd:d9:dd:c25:c25:94de:9810/1282c19:dd:d9:dd:c25:c25:94de:9810
182c19:dd:d9:dd:c25:c25:94de:9811/1282c19:dd:d9:dd:c25:c25:94de:9811
192c19:dd:d9:dd:c25:c25:94de:9812/1282c19:dd:d9:dd:c25:c25:94de:9812
202c19:dd:d9:dd:c25:c25:94de:9813/1282c19:dd:d9:dd:c25:c25:94de:9813
212c19:dd:d9:dd:c25:c25:94de:9814/1282c19:dd:d9:dd:c25:c25:94de:9814
222c19:dd:d9:dd:c25:c25:94de:9815/1282c19:dd:d9:dd:c25:c25:94de:9815
232c19:dd:d9:dd:c25:c25:94de:9816/1282c19:dd:d9:dd:c25:c25:94de:9816
242c19:dd:d9:dd:c25:c25:94de:9817/1282c19:dd:d9:dd:c25:c25:94de:9817
252c19:dd:d9:dd:c25:c25:94de:9818/1282c19:dd:d9:dd:c25:c25:94de:9818
262c19:dd:d9:dd:c25:c25:94de:9819/1282c19:dd:d9:dd:c25:c25:94de:9819
272c19:dd:d9:dd:c25:c25:94de:981a/1282c19:dd:d9:dd:c25:c25:94de:981a
282c19:dd:d9:dd:c25:c25:94de:981b/1282c19:dd:d9:dd:c25:c25:94de:981b
292c19:dd:d9:dd:c25:c25:94de:981c/1282c19:dd:d9:dd:c25:c25:94de:981c
302c19:dd:d9:dd:c25:c25:94de:981d/1282c19:dd:d9:dd:c25:c25:94de:981d
312c19:dd:d9:dd:c25:c25:94de:981e/1282c19:dd:d9:dd:c25:c25:94de:981e
322c19:dd:d9:dd:c25:c25:94de:981f/1282c19:dd:d9:dd:c25:c25:94de:981f
332c19:dd:d9:dd:c25:c25:94de:9820/1282c19:dd:d9:dd:c25:c25:94de:9820
342c19:dd:d9:dd:c25:c25:94de:9821/1282c19:dd:d9:dd:c25:c25:94de:9821
352c19:dd:d9:dd:c25:c25:94de:9822/1282c19:dd:d9:dd:c25:c25:94de:9822
362c19:dd:d9:dd:c25:c25:94de:9823/1282c19:dd:d9:dd:c25:c25:94de:9823
372c19:dd:d9:dd:c25:c25:94de:9824/1282c19:dd:d9:dd:c25:c25:94de:9824
382c19:dd:d9:dd:c25:c25:94de:9825/1282c19:dd:d9:dd:c25:c25:94de:9825
392c19:dd:d9:dd:c25:c25:94de:9826/1282c19:dd:d9:dd:c25:c25:94de:9826
402c19:dd:d9:dd:c25:c25:94de:9827/1282c19:dd:d9:dd:c25:c25:94de:9827
412c19:dd:d9:dd:c25:c25:94de:9828/1282c19:dd:d9:dd:c25:c25:94de:9828
422c19:dd:d9:dd:c25:c25:94de:9829/1282c19:dd:d9:dd:c25:c25:94de:9829
432c19:dd:d9:dd:c25:c25:94de:982a/1282c19:dd:d9:dd:c25:c25:94de:982a
442c19:dd:d9:dd:c25:c25:94de:982b/1282c19:dd:d9:dd:c25:c25:94de:982b
452c19:dd:d9:dd:c25:c25:94de:982c/1282c19:dd:d9:dd:c25:c25:94de:982c
462c19:dd:d9:dd:c25:c25:94de:982d/1282c19:dd:d9:dd:c25:c25:94de:982d
472c19:dd:d9:dd:c25:c25:94de:982e/1282c19:dd:d9:dd:c25:c25:94de:982e
482c19:dd:d9:dd:c25:c25:94de:982f/1282c19:dd:d9:dd:c25:c25:94de:982f
492c19:dd:d9:dd:c25:c25:94de:9830/1282c19:dd:d9:dd:c25:c25:94de:9830
502c19:dd:d9:dd:c25:c25:94de:9831/1282c19:dd:d9:dd:c25:c25:94de:9831
512c19:dd:d9:dd:c25:c25:94de:9832/1282c19:dd:d9:dd:c25:c25:94de:9832
522c19:dd:d9:dd:c25:c25:94de:9833/1282c19:dd:d9:dd:c25:c25:94de:9833
532c19:dd:d9:dd:c25:c25:94de:9834/1282c19:dd:d9:dd:c25:c25:94de:9834
542c19:dd:d9:dd:c25:c25:94de:9835/1282c19:dd:d9:dd:c25:c25:94de:9835
552c19:dd:d9:dd:c25:c25:94de:9836/1282c19:dd:d9:dd:c25:c25:94de:9836
562c19:dd:d9:dd:c25:c25:94de:9837/1282c19:dd:d9:dd:c25:c25:94de:9837
572c19:dd:d9:dd:c25:c25:94de:9838/1282c19:dd:d9:dd:c25:c25:94de:9838
582c19:dd:d9:dd:c25:c25:94de:9839/1282c19:dd:d9:dd:c25:c25:94de:9839
592c19:dd:d9:dd:c25:c25:94de:983a/1282c19:dd:d9:dd:c25:c25:94de:983a
602c19:dd:d9:dd:c25:c25:94de:983b/1282c19:dd:d9:dd:c25:c25:94de:983b
612c19:dd:d9:dd:c25:c25:94de:983c/1282c19:dd:d9:dd:c25:c25:94de:983c
622c19:dd:d9:dd:c25:c25:94de:983d/1282c19:dd:d9:dd:c25:c25:94de:983d
632c19:dd:d9:dd:c25:c25:94de:983e/1282c19:dd:d9:dd:c25:c25:94de:983e
642c19:dd:d9:dd:c25:c25:94de:983f/1282c19:dd:d9:dd:c25:c25:94de:983f
652c19:dd:d9:dd:c25:c25:94de:9840/1282c19:dd:d9:dd:c25:c25:94de:9840
662c19:dd:d9:dd:c25:c25:94de:9841/1282c19:dd:d9:dd:c25:c25:94de:9841
672c19:dd:d9:dd:c25:c25:94de:9842/1282c19:dd:d9:dd:c25:c25:94de:9842
682c19:dd:d9:dd:c25:c25:94de:9843/1282c19:dd:d9:dd:c25:c25:94de:9843
692c19:dd:d9:dd:c25:c25:94de:9844/1282c19:dd:d9:dd:c25:c25:94de:9844
702c19:dd:d9:dd:c25:c25:94de:9845/1282c19:dd:d9:dd:c25:c25:94de:9845
712c19:dd:d9:dd:c25:c25:94de:9846/1282c19:dd:d9:dd:c25:c25:94de:9846
722c19:dd:d9:dd:c25:c25:94de:9847/1282c19:dd:d9:dd:c25:c25:94de:9847
732c19:dd:d9:dd:c25:c25:94de:9848/1282c19:dd:d9:dd:c25:c25:94de:9848
742c19:dd:d9:dd:c25:c25:94de:9849/1282c19:dd:d9:dd:c25:c25:94de:9849
752c19:dd:d9:dd:c25:c25:94de:984a/1282c19:dd:d9:dd:c25:c25:94de:984a
762c19:dd:d9:dd:c25:c25:94de:984b/1282c19:dd:d9:dd:c25:c25:94de:984b
772c19:dd:d9:dd:c25:c25:94de:984c/1282c19:dd:d9:dd:c25:c25:94de:984c
782c19:dd:d9:dd:c25:c25:94de:984d/1282c19:dd:d9:dd:c25:c25:94de:984d
792c19:dd:d9:dd:c25:c25:94de:984e/1282c19:dd:d9:dd:c25:c25:94de:984e
802c19:dd:d9:dd:c25:c25:94de:984f/1282c19:dd:d9:dd:c25:c25:94de:984f
812c19:dd:d9:dd:c25:c25:94de:9850/1282c19:dd:d9:dd:c25:c25:94de:9850
822c19:dd:d9:dd:c25:c25:94de:9851/1282c19:dd:d9:dd:c25:c25:94de:9851
832c19:dd:d9:dd:c25:c25:94de:9852/1282c19:dd:d9:dd:c25:c25:94de:9852
842c19:dd:d9:dd:c25:c25:94de:9853/1282c19:dd:d9:dd:c25:c25:94de:9853
852c19:dd:d9:dd:c25:c25:94de:9854/1282c19:dd:d9:dd:c25:c25:94de:9854
862c19:dd:d9:dd:c25:c25:94de:9855/1282c19:dd:d9:dd:c25:c25:94de:9855
872c19:dd:d9:dd:c25:c25:94de:9856/1282c19:dd:d9:dd:c25:c25:94de:9856
882c19:dd:d9:dd:c25:c25:94de:9857/1282c19:dd:d9:dd:c25:c25:94de:9857
892c19:dd:d9:dd:c25:c25:94de:9858/1282c19:dd:d9:dd:c25:c25:94de:9858
902c19:dd:d9:dd:c25:c25:94de:9859/1282c19:dd:d9:dd:c25:c25:94de:9859
912c19:dd:d9:dd:c25:c25:94de:985a/1282c19:dd:d9:dd:c25:c25:94de:985a
922c19:dd:d9:dd:c25:c25:94de:985b/1282c19:dd:d9:dd:c25:c25:94de:985b
932c19:dd:d9:dd:c25:c25:94de:985c/1282c19:dd:d9:dd:c25:c25:94de:985c
942c19:dd:d9:dd:c25:c25:94de:985d/1282c19:dd:d9:dd:c25:c25:94de:985d
952c19:dd:d9:dd:c25:c25:94de:985e/1282c19:dd:d9:dd:c25:c25:94de:985e
962c19:dd:d9:dd:c25:c25:94de:985f/1282c19:dd:d9:dd:c25:c25:94de:985f
972c19:dd:d9:dd:c25:c25:94de:9860/1282c19:dd:d9:dd:c25:c25:94de:9860
982c19:dd:d9:dd:c25:c25:94de:9861/1282c19:dd:d9:dd:c25:c25:94de:9861
992c19:dd:d9:dd:c25:c25:94de:9862/1282c19:dd:d9:dd:c25:c25:94de:9862
1002c19:dd:d9:dd:c25:c25:94de:9863/1282c19:dd:d9:dd:c25:c25:94de:9863
1012c19:dd:d9:dd:c25:c25:94de:9864/1282c19:dd:d9:dd:c25:c25:94de:9864
1022c19:dd:d9:dd:c25:c25:94de:9865/1282c19:dd:d9:dd:c25:c25:94de:9865
1032c19:dd:d9:dd:c25:c25:94de:9866/1282c19:dd:d9:dd:c25:c25:94de:9866
1042c19:dd:d9:dd:c25:c25:94de:9867/1282c19:dd:d9:dd:c25:c25:94de:9867
1052c19:dd:d9:dd:c25:c25:94de:9868/1282c19:dd:d9:dd:c25:c25:94de:9868
1062c19:dd:d9:dd:c25:c25:94de:9869/1282c19:dd:d9:dd:c25:c25:94de:9869
1072c19:dd:d9:dd:c25:c25:94de:986a/1282c19:dd:d9:dd:c25:c25:94de:986a
1082c19:dd:d9:dd:c25:c25:94de:986b/1282c19:dd:d9:dd:c25:c25:94de:986b
1092c19:dd:d9:dd:c25:c25:94de:986c/1282c19:dd:d9:dd:c25:c25:94de:986c
1102c19:dd:d9:dd:c25:c25:94de:986d/1282c19:dd:d9:dd:c25:c25:94de:986d
1112c19:dd:d9:dd:c25:c25:94de:986e/1282c19:dd:d9:dd:c25:c25:94de:986e
1122c19:dd:d9:dd:c25:c25:94de:986f/1282c19:dd:d9:dd:c25:c25:94de:986f
1132c19:dd:d9:dd:c25:c25:94de:9870/1282c19:dd:d9:dd:c25:c25:94de:9870
1142c19:dd:d9:dd:c25:c25:94de:9871/1282c19:dd:d9:dd:c25:c25:94de:9871
1152c19:dd:d9:dd:c25:c25:94de:9872/1282c19:dd:d9:dd:c25:c25:94de:9872
1162c19:dd:d9:dd:c25:c25:94de:9873/1282c19:dd:d9:dd:c25:c25:94de:9873
1172c19:dd:d9:dd:c25:c25:94de:9874/1282c19:dd:d9:dd:c25:c25:94de:9874
1182c19:dd:d9:dd:c25:c25:94de:9875/1282c19:dd:d9:dd:c25:c25:94de:9875
1192c19:dd:d9:dd:c25:c25:94de:9876/1282c19:dd:d9:dd:c25:c25:94de:9876
1202c19:dd:d9:dd:c25:c25:94de:9877/1282c19:dd:d9:dd:c25:c25:94de:9877
1212c19:dd:d9:dd:c25:c25:94de:9878/1282c19:dd:d9:dd:c25:c25:94de:9878
1222c19:dd:d9:dd:c25:c25:94de:9879/1282c19:dd:d9:dd:c25:c25:94de:9879
1232c19:dd:d9:dd:c25:c25:94de:987a/1282c19:dd:d9:dd:c25:c25:94de:987a
1242c19:dd:d9:dd:c25:c25:94de:987b/1282c19:dd:d9:dd:c25:c25:94de:987b
1252c19:dd:d9:dd:c25:c25:94de:987c/1282c19:dd:d9:dd:c25:c25:94de:987c
1262c19:dd:d9:dd:c25:c25:94de:987d/1282c19:dd:d9:dd:c25:c25:94de:987d
1272c19:dd:d9:dd:c25:c25:94de:987e/1282c19:dd:d9:dd:c25:c25:94de:987e
1282c19:dd:d9:dd:c25:c25:94de:987f/1282c19:dd:d9:dd:c25:c25:94de:987f
1292c19:dd:d9:dd:c25:c25:94de:9880/1282c19:dd:d9:dd:c25:c25:94de:9880
1302c19:dd:d9:dd:c25:c25:94de:9881/1282c19:dd:d9:dd:c25:c25:94de:9881
1312c19:dd:d9:dd:c25:c25:94de:9882/1282c19:dd:d9:dd:c25:c25:94de:9882
1322c19:dd:d9:dd:c25:c25:94de:9883/1282c19:dd:d9:dd:c25:c25:94de:9883
1332c19:dd:d9:dd:c25:c25:94de:9884/1282c19:dd:d9:dd:c25:c25:94de:9884
1342c19:dd:d9:dd:c25:c25:94de:9885/1282c19:dd:d9:dd:c25:c25:94de:9885
1352c19:dd:d9:dd:c25:c25:94de:9886/1282c19:dd:d9:dd:c25:c25:94de:9886
1362c19:dd:d9:dd:c25:c25:94de:9887/1282c19:dd:d9:dd:c25:c25:94de:9887
1372c19:dd:d9:dd:c25:c25:94de:9888/1282c19:dd:d9:dd:c25:c25:94de:9888
1382c19:dd:d9:dd:c25:c25:94de:9889/1282c19:dd:d9:dd:c25:c25:94de:9889
1392c19:dd:d9:dd:c25:c25:94de:988a/1282c19:dd:d9:dd:c25:c25:94de:988a
1402c19:dd:d9:dd:c25:c25:94de:988b/1282c19:dd:d9:dd:c25:c25:94de:988b
1412c19:dd:d9:dd:c25:c25:94de:988c/1282c19:dd:d9:dd:c25:c25:94de:988c
1422c19:dd:d9:dd:c25:c25:94de:988d/1282c19:dd:d9:dd:c25:c25:94de:988d
1432c19:dd:d9:dd:c25:c25:94de:988e/1282c19:dd:d9:dd:c25:c25:94de:988e
1442c19:dd:d9:dd:c25:c25:94de:988f/1282c19:dd:d9:dd:c25:c25:94de:988f
1452c19:dd:d9:dd:c25:c25:94de:9890/1282c19:dd:d9:dd:c25:c25:94de:9890
1462c19:dd:d9:dd:c25:c25:94de:9891/1282c19:dd:d9:dd:c25:c25:94de:9891
1472c19:dd:d9:dd:c25:c25:94de:9892/1282c19:dd:d9:dd:c25:c25:94de:9892
1482c19:dd:d9:dd:c25:c25:94de:9893/1282c19:dd:d9:dd:c25:c25:94de:9893
1492c19:dd:d9:dd:c25:c25:94de:9894/1282c19:dd:d9:dd:c25:c25:94de:9894
1502c19:dd:d9:dd:c25:c25:94de:9895/1282c19:dd:d9:dd:c25:c25:94de:9895
1512c19:dd:d9:dd:c25:c25:94de:9896/1282c19:dd:d9:dd:c25:c25:94de:9896
1522c19:dd:d9:dd:c25:c25:94de:9897/1282c19:dd:d9:dd:c25:c25:94de:9897
1532c19:dd:d9:dd:c25:c25:94de:9898/1282c19:dd:d9:dd:c25:c25:94de:9898
1542c19:dd:d9:dd:c25:c25:94de:9899/1282c19:dd:d9:dd:c25:c25:94de:9899
1552c19:dd:d9:dd:c25:c25:94de:989a/1282c19:dd:d9:dd:c25:c25:94de:989a
1562c19:dd:d9:dd:c25:c25:94de:989b/1282c19:dd:d9:dd:c25:c25:94de:989b
1572c19:dd:d9:dd:c25:c25:94de:989c/1282c19:dd:d9:dd:c25:c25:94de:989c
1582c19:dd:d9:dd:c25:c25:94de:989d/1282c19:dd:d9:dd:c25:c25:94de:989d
1592c19:dd:d9:dd:c25:c25:94de:989e/1282c19:dd:d9:dd:c25:c25:94de:989e
1602c19:dd:d9:dd:c25:c25:94de:989f/1282c19:dd:d9:dd:c25:c25:94de:989f
1612c19:dd:d9:dd:c25:c25:94de:98a0/1282c19:dd:d9:dd:c25:c25:94de:98a0
1622c19:dd:d9:dd:c25:c25:94de:98a1/1282c19:dd:d9:dd:c25:c25:94de:98a1
1632c19:dd:d9:dd:c25:c25:94de:98a2/1282c19:dd:d9:dd:c25:c25:94de:98a2
1642c19:dd:d9:dd:c25:c25:94de:98a3/1282c19:dd:d9:dd:c25:c25:94de:98a3
1652c19:dd:d9:dd:c25:c25:94de:98a4/1282c19:dd:d9:dd:c25:c25:94de:98a4
1662c19:dd:d9:dd:c25:c25:94de:98a5/1282c19:dd:d9:dd:c25:c25:94de:98a5
1672c19:dd:d9:dd:c25:c25:94de:98a6/1282c19:dd:d9:dd:c25:c25:94de:98a6
1682c19:dd:d9:dd:c25:c25:94de:98a7/1282c19:dd:d9:dd:c25:c25:94de:98a7
1692c19:dd:d9:dd:c25:c25:94de:98a8/1282c19:dd:d9:dd:c25:c25:94de:98a8
1702c19:dd:d9:dd:c25:c25:94de:98a9/1282c19:dd:d9:dd:c25:c25:94de:98a9
1712c19:dd:d9:dd:c25:c25:94de:98aa/1282c19:dd:d9:dd:c25:c25:94de:98aa
1722c19:dd:d9:dd:c25:c25:94de:98ab/1282c19:dd:d9:dd:c25:c25:94de:98ab
1732c19:dd:d9:dd:c25:c25:94de:98ac/1282c19:dd:d9:dd:c25:c25:94de:98ac
1742c19:dd:d9:dd:c25:c25:94de:98ad/1282c19:dd:d9:dd:c25:c25:94de:98ad
1752c19:dd:d9:dd:c25:c25:94de:98ae/1282c19:dd:d9:dd:c25:c25:94de:98ae
1762c19:dd:d9:dd:c25:c25:94de:98af/1282c19:dd:d9:dd:c25:c25:94de:98af
1772c19:dd:d9:dd:c25:c25:94de:98b0/1282c19:dd:d9:dd:c25:c25:94de:98b0
1782c19:dd:d9:dd:c25:c25:94de:98b1/1282c19:dd:d9:dd:c25:c25:94de:98b1
1792c19:dd:d9:dd:c25:c25:94de:98b2/1282c19:dd:d9:dd:c25:c25:94de:98b2
1802c19:dd:d9:dd:c25:c25:94de:98b3/1282c19:dd:d9:dd:c25:c25:94de:98b3
1812c19:dd:d9:dd:c25:c25:94de:98b4/1282c19:dd:d9:dd:c25:c25:94de:98b4
1822c19:dd:d9:dd:c25:c25:94de:98b5/1282c19:dd:d9:dd:c25:c25:94de:98b5
1832c19:dd:d9:dd:c25:c25:94de:98b6/1282c19:dd:d9:dd:c25:c25:94de:98b6
1842c19:dd:d9:dd:c25:c25:94de:98b7/1282c19:dd:d9:dd:c25:c25:94de:98b7
1852c19:dd:d9:dd:c25:c25:94de:98b8/1282c19:dd:d9:dd:c25:c25:94de:98b8
1862c19:dd:d9:dd:c25:c25:94de:98b9/1282c19:dd:d9:dd:c25:c25:94de:98b9
1872c19:dd:d9:dd:c25:c25:94de:98ba/1282c19:dd:d9:dd:c25:c25:94de:98ba
1882c19:dd:d9:dd:c25:c25:94de:98bb/1282c19:dd:d9:dd:c25:c25:94de:98bb
1892c19:dd:d9:dd:c25:c25:94de:98bc/1282c19:dd:d9:dd:c25:c25:94de:98bc
1902c19:dd:d9:dd:c25:c25:94de:98bd/1282c19:dd:d9:dd:c25:c25:94de:98bd
1912c19:dd:d9:dd:c25:c25:94de:98be/1282c19:dd:d9:dd:c25:c25:94de:98be
1922c19:dd:d9:dd:c25:c25:94de:98bf/1282c19:dd:d9:dd:c25:c25:94de:98bf
1932c19:dd:d9:dd:c25:c25:94de:98c0/1282c19:dd:d9:dd:c25:c25:94de:98c0
1942c19:dd:d9:dd:c25:c25:94de:98c1/1282c19:dd:d9:dd:c25:c25:94de:98c1
1952c19:dd:d9:dd:c25:c25:94de:98c2/1282c19:dd:d9:dd:c25:c25:94de:98c2
1962c19:dd:d9:dd:c25:c25:94de:98c3/1282c19:dd:d9:dd:c25:c25:94de:98c3
1972c19:dd:d9:dd:c25:c25:94de:98c4/1282c19:dd:d9:dd:c25:c25:94de:98c4
1982c19:dd:d9:dd:c25:c25:94de:98c5/1282c19:dd:d9:dd:c25:c25:94de:98c5
1992c19:dd:d9:dd:c25:c25:94de:98c6/1282c19:dd:d9:dd:c25:c25:94de:98c6
2002c19:dd:d9:dd:c25:c25:94de:98c7/1282c19:dd:d9:dd:c25:c25:94de:98c7
2012c19:dd:d9:dd:c25:c25:94de:98c8/1282c19:dd:d9:dd:c25:c25:94de:98c8
2022c19:dd:d9:dd:c25:c25:94de:98c9/1282c19:dd:d9:dd:c25:c25:94de:98c9
2032c19:dd:d9:dd:c25:c25:94de:98ca/1282c19:dd:d9:dd:c25:c25:94de:98ca
2042c19:dd:d9:dd:c25:c25:94de:98cb/1282c19:dd:d9:dd:c25:c25:94de:98cb
2052c19:dd:d9:dd:c25:c25:94de:98cc/1282c19:dd:d9:dd:c25:c25:94de:98cc
2062c19:dd:d9:dd:c25:c25:94de:98cd/1282c19:dd:d9:dd:c25:c25:94de:98cd
2072c19:dd:d9:dd:c25:c25:94de:98ce/1282c19:dd:d9:dd:c25:c25:94de:98ce
2082c19:dd:d9:dd:c25:c25:94de:98cf/1282c19:dd:d9:dd:c25:c25:94de:98cf
2092c19:dd:d9:dd:c25:c25:94de:98d0/1282c19:dd:d9:dd:c25:c25:94de:98d0
2102c19:dd:d9:dd:c25:c25:94de:98d1/1282c19:dd:d9:dd:c25:c25:94de:98d1
2112c19:dd:d9:dd:c25:c25:94de:98d2/1282c19:dd:d9:dd:c25:c25:94de:98d2
2122c19:dd:d9:dd:c25:c25:94de:98d3/1282c19:dd:d9:dd:c25:c25:94de:98d3
2132c19:dd:d9:dd:c25:c25:94de:98d4/1282c19:dd:d9:dd:c25:c25:94de:98d4
2142c19:dd:d9:dd:c25:c25:94de:98d5/1282c19:dd:d9:dd:c25:c25:94de:98d5
2152c19:dd:d9:dd:c25:c25:94de:98d6/1282c19:dd:d9:dd:c25:c25:94de:98d6
2162c19:dd:d9:dd:c25:c25:94de:98d7/1282c19:dd:d9:dd:c25:c25:94de:98d7
2172c19:dd:d9:dd:c25:c25:94de:98d8/1282c19:dd:d9:dd:c25:c25:94de:98d8
2182c19:dd:d9:dd:c25:c25:94de:98d9/1282c19:dd:d9:dd:c25:c25:94de:98d9
2192c19:dd:d9:dd:c25:c25:94de:98da/1282c19:dd:d9:dd:c25:c25:94de:98da
2202c19:dd:d9:dd:c25:c25:94de:98db/1282c19:dd:d9:dd:c25:c25:94de:98db
2212c19:dd:d9:dd:c25:c25:94de:98dc/1282c19:dd:d9:dd:c25:c25:94de:98dc
2222c19:dd:d9:dd:c25:c25:94de:98dd/1282c19:dd:d9:dd:c25:c25:94de:98dd
2232c19:dd:d9:dd:c25:c25:94de:98de/1282c19:dd:d9:dd:c25:c25:94de:98de
2242c19:dd:d9:dd:c25:c25:94de:98df/1282c19:dd:d9:dd:c25:c25:94de:98df
2252c19:dd:d9:dd:c25:c25:94de:98e0/1282c19:dd:d9:dd:c25:c25:94de:98e0
2262c19:dd:d9:dd:c25:c25:94de:98e1/1282c19:dd:d9:dd:c25:c25:94de:98e1
2272c19:dd:d9:dd:c25:c25:94de:98e2/1282c19:dd:d9:dd:c25:c25:94de:98e2
2282c19:dd:d9:dd:c25:c25:94de:98e3/1282c19:dd:d9:dd:c25:c25:94de:98e3
2292c19:dd:d9:dd:c25:c25:94de:98e4/1282c19:dd:d9:dd:c25:c25:94de:98e4
2302c19:dd:d9:dd:c25:c25:94de:98e5/1282c19:dd:d9:dd:c25:c25:94de:98e5
2312c19:dd:d9:dd:c25:c25:94de:98e6/1282c19:dd:d9:dd:c25:c25:94de:98e6
2322c19:dd:d9:dd:c25:c25:94de:98e7/1282c19:dd:d9:dd:c25:c25:94de:98e7
2332c19:dd:d9:dd:c25:c25:94de:98e8/1282c19:dd:d9:dd:c25:c25:94de:98e8
2342c19:dd:d9:dd:c25:c25:94de:98e9/1282c19:dd:d9:dd:c25:c25:94de:98e9
2352c19:dd:d9:dd:c25:c25:94de:98ea/1282c19:dd:d9:dd:c25:c25:94de:98ea
2362c19:dd:d9:dd:c25:c25:94de:98eb/1282c19:dd:d9:dd:c25:c25:94de:98eb
2372c19:dd:d9:dd:c25:c25:94de:98ec/1282c19:dd:d9:dd:c25:c25:94de:98ec
2382c19:dd:d9:dd:c25:c25:94de:98ed/1282c19:dd:d9:dd:c25:c25:94de:98ed
2392c19:dd:d9:dd:c25:c25:94de:98ee/1282c19:dd:d9:dd:c25:c25:94de:98ee
2402c19:dd:d9:dd:c25:c25:94de:98ef/1282c19:dd:d9:dd:c25:c25:94de:98ef
2412c19:dd:d9:dd:c25:c25:94de:98f0/1282c19:dd:d9:dd:c25:c25:94de:98f0
2422c19:dd:d9:dd:c25:c25:94de:98f1/1282c19:dd:d9:dd:c25:c25:94de:98f1
2432c19:dd:d9:dd:c25:c25:94de:98f2/1282c19:dd:d9:dd:c25:c25:94de:98f2
2442c19:dd:d9:dd:c25:c25:94de:98f3/1282c19:dd:d9:dd:c25:c25:94de:98f3
2452c19:dd:d9:dd:c25:c25:94de:98f4/1282c19:dd:d9:dd:c25:c25:94de:98f4
2462c19:dd:d9:dd:c25:c25:94de:98f5/1282c19:dd:d9:dd:c25:c25:94de:98f5
2472c19:dd:d9:dd:c25:c25:94de:98f6/1282c19:dd:d9:dd:c25:c25:94de:98f6
2482c19:dd:d9:dd:c25:c25:94de:98f7/1282c19:dd:d9:dd:c25:c25:94de:98f7
2492c19:dd:d9:dd:c25:c25:94de:98f8/1282c19:dd:d9:dd:c25:c25:94de:98f8
2502c19:dd:d9:dd:c25:c25:94de:98f9/1282c19:dd:d9:dd:c25:c25:94de:98f9
2512c19:dd:d9:dd:c25:c25:94de:98fa/1282c19:dd:d9:dd:c25:c25:94de:98fa
2522c19:dd:d9:dd:c25:c25:94de:98fb/1282c19:dd:d9:dd:c25:c25:94de:98fb
2532c19:dd:d9:dd:c25:c25:94de:98fc/1282c19:dd:d9:dd:c25:c25:94de:98fc
2542c19:dd:d9:dd:c25:c25:94de:98fd/1282c19:dd:d9:dd:c25:c25:94de:98fd
2552c19:dd:d9:dd:c25:c25:94de:98fe/1282c19:dd:d9:dd:c25:c25:94de:98fe
2562c19:dd:d9:dd:c25:c25:94de:98ff/1282c19:dd:d9:dd:c25:c25:94de:98ff

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.