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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:8600/120
First address
2c19:dd:d9:dd:c25:c25:94de:8600
Last address
2c19:dd:d9:dd:c25:c25:94de:86ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:8600
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
6.8.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:8600/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:8600/1282c19:dd:d9:dd:c25:c25:94de:8600
22c19:dd:d9:dd:c25:c25:94de:8601/1282c19:dd:d9:dd:c25:c25:94de:8601
32c19:dd:d9:dd:c25:c25:94de:8602/1282c19:dd:d9:dd:c25:c25:94de:8602
42c19:dd:d9:dd:c25:c25:94de:8603/1282c19:dd:d9:dd:c25:c25:94de:8603
52c19:dd:d9:dd:c25:c25:94de:8604/1282c19:dd:d9:dd:c25:c25:94de:8604
62c19:dd:d9:dd:c25:c25:94de:8605/1282c19:dd:d9:dd:c25:c25:94de:8605
72c19:dd:d9:dd:c25:c25:94de:8606/1282c19:dd:d9:dd:c25:c25:94de:8606
82c19:dd:d9:dd:c25:c25:94de:8607/1282c19:dd:d9:dd:c25:c25:94de:8607
92c19:dd:d9:dd:c25:c25:94de:8608/1282c19:dd:d9:dd:c25:c25:94de:8608
102c19:dd:d9:dd:c25:c25:94de:8609/1282c19:dd:d9:dd:c25:c25:94de:8609
112c19:dd:d9:dd:c25:c25:94de:860a/1282c19:dd:d9:dd:c25:c25:94de:860a
122c19:dd:d9:dd:c25:c25:94de:860b/1282c19:dd:d9:dd:c25:c25:94de:860b
132c19:dd:d9:dd:c25:c25:94de:860c/1282c19:dd:d9:dd:c25:c25:94de:860c
142c19:dd:d9:dd:c25:c25:94de:860d/1282c19:dd:d9:dd:c25:c25:94de:860d
152c19:dd:d9:dd:c25:c25:94de:860e/1282c19:dd:d9:dd:c25:c25:94de:860e
162c19:dd:d9:dd:c25:c25:94de:860f/1282c19:dd:d9:dd:c25:c25:94de:860f
172c19:dd:d9:dd:c25:c25:94de:8610/1282c19:dd:d9:dd:c25:c25:94de:8610
182c19:dd:d9:dd:c25:c25:94de:8611/1282c19:dd:d9:dd:c25:c25:94de:8611
192c19:dd:d9:dd:c25:c25:94de:8612/1282c19:dd:d9:dd:c25:c25:94de:8612
202c19:dd:d9:dd:c25:c25:94de:8613/1282c19:dd:d9:dd:c25:c25:94de:8613
212c19:dd:d9:dd:c25:c25:94de:8614/1282c19:dd:d9:dd:c25:c25:94de:8614
222c19:dd:d9:dd:c25:c25:94de:8615/1282c19:dd:d9:dd:c25:c25:94de:8615
232c19:dd:d9:dd:c25:c25:94de:8616/1282c19:dd:d9:dd:c25:c25:94de:8616
242c19:dd:d9:dd:c25:c25:94de:8617/1282c19:dd:d9:dd:c25:c25:94de:8617
252c19:dd:d9:dd:c25:c25:94de:8618/1282c19:dd:d9:dd:c25:c25:94de:8618
262c19:dd:d9:dd:c25:c25:94de:8619/1282c19:dd:d9:dd:c25:c25:94de:8619
272c19:dd:d9:dd:c25:c25:94de:861a/1282c19:dd:d9:dd:c25:c25:94de:861a
282c19:dd:d9:dd:c25:c25:94de:861b/1282c19:dd:d9:dd:c25:c25:94de:861b
292c19:dd:d9:dd:c25:c25:94de:861c/1282c19:dd:d9:dd:c25:c25:94de:861c
302c19:dd:d9:dd:c25:c25:94de:861d/1282c19:dd:d9:dd:c25:c25:94de:861d
312c19:dd:d9:dd:c25:c25:94de:861e/1282c19:dd:d9:dd:c25:c25:94de:861e
322c19:dd:d9:dd:c25:c25:94de:861f/1282c19:dd:d9:dd:c25:c25:94de:861f
332c19:dd:d9:dd:c25:c25:94de:8620/1282c19:dd:d9:dd:c25:c25:94de:8620
342c19:dd:d9:dd:c25:c25:94de:8621/1282c19:dd:d9:dd:c25:c25:94de:8621
352c19:dd:d9:dd:c25:c25:94de:8622/1282c19:dd:d9:dd:c25:c25:94de:8622
362c19:dd:d9:dd:c25:c25:94de:8623/1282c19:dd:d9:dd:c25:c25:94de:8623
372c19:dd:d9:dd:c25:c25:94de:8624/1282c19:dd:d9:dd:c25:c25:94de:8624
382c19:dd:d9:dd:c25:c25:94de:8625/1282c19:dd:d9:dd:c25:c25:94de:8625
392c19:dd:d9:dd:c25:c25:94de:8626/1282c19:dd:d9:dd:c25:c25:94de:8626
402c19:dd:d9:dd:c25:c25:94de:8627/1282c19:dd:d9:dd:c25:c25:94de:8627
412c19:dd:d9:dd:c25:c25:94de:8628/1282c19:dd:d9:dd:c25:c25:94de:8628
422c19:dd:d9:dd:c25:c25:94de:8629/1282c19:dd:d9:dd:c25:c25:94de:8629
432c19:dd:d9:dd:c25:c25:94de:862a/1282c19:dd:d9:dd:c25:c25:94de:862a
442c19:dd:d9:dd:c25:c25:94de:862b/1282c19:dd:d9:dd:c25:c25:94de:862b
452c19:dd:d9:dd:c25:c25:94de:862c/1282c19:dd:d9:dd:c25:c25:94de:862c
462c19:dd:d9:dd:c25:c25:94de:862d/1282c19:dd:d9:dd:c25:c25:94de:862d
472c19:dd:d9:dd:c25:c25:94de:862e/1282c19:dd:d9:dd:c25:c25:94de:862e
482c19:dd:d9:dd:c25:c25:94de:862f/1282c19:dd:d9:dd:c25:c25:94de:862f
492c19:dd:d9:dd:c25:c25:94de:8630/1282c19:dd:d9:dd:c25:c25:94de:8630
502c19:dd:d9:dd:c25:c25:94de:8631/1282c19:dd:d9:dd:c25:c25:94de:8631
512c19:dd:d9:dd:c25:c25:94de:8632/1282c19:dd:d9:dd:c25:c25:94de:8632
522c19:dd:d9:dd:c25:c25:94de:8633/1282c19:dd:d9:dd:c25:c25:94de:8633
532c19:dd:d9:dd:c25:c25:94de:8634/1282c19:dd:d9:dd:c25:c25:94de:8634
542c19:dd:d9:dd:c25:c25:94de:8635/1282c19:dd:d9:dd:c25:c25:94de:8635
552c19:dd:d9:dd:c25:c25:94de:8636/1282c19:dd:d9:dd:c25:c25:94de:8636
562c19:dd:d9:dd:c25:c25:94de:8637/1282c19:dd:d9:dd:c25:c25:94de:8637
572c19:dd:d9:dd:c25:c25:94de:8638/1282c19:dd:d9:dd:c25:c25:94de:8638
582c19:dd:d9:dd:c25:c25:94de:8639/1282c19:dd:d9:dd:c25:c25:94de:8639
592c19:dd:d9:dd:c25:c25:94de:863a/1282c19:dd:d9:dd:c25:c25:94de:863a
602c19:dd:d9:dd:c25:c25:94de:863b/1282c19:dd:d9:dd:c25:c25:94de:863b
612c19:dd:d9:dd:c25:c25:94de:863c/1282c19:dd:d9:dd:c25:c25:94de:863c
622c19:dd:d9:dd:c25:c25:94de:863d/1282c19:dd:d9:dd:c25:c25:94de:863d
632c19:dd:d9:dd:c25:c25:94de:863e/1282c19:dd:d9:dd:c25:c25:94de:863e
642c19:dd:d9:dd:c25:c25:94de:863f/1282c19:dd:d9:dd:c25:c25:94de:863f
652c19:dd:d9:dd:c25:c25:94de:8640/1282c19:dd:d9:dd:c25:c25:94de:8640
662c19:dd:d9:dd:c25:c25:94de:8641/1282c19:dd:d9:dd:c25:c25:94de:8641
672c19:dd:d9:dd:c25:c25:94de:8642/1282c19:dd:d9:dd:c25:c25:94de:8642
682c19:dd:d9:dd:c25:c25:94de:8643/1282c19:dd:d9:dd:c25:c25:94de:8643
692c19:dd:d9:dd:c25:c25:94de:8644/1282c19:dd:d9:dd:c25:c25:94de:8644
702c19:dd:d9:dd:c25:c25:94de:8645/1282c19:dd:d9:dd:c25:c25:94de:8645
712c19:dd:d9:dd:c25:c25:94de:8646/1282c19:dd:d9:dd:c25:c25:94de:8646
722c19:dd:d9:dd:c25:c25:94de:8647/1282c19:dd:d9:dd:c25:c25:94de:8647
732c19:dd:d9:dd:c25:c25:94de:8648/1282c19:dd:d9:dd:c25:c25:94de:8648
742c19:dd:d9:dd:c25:c25:94de:8649/1282c19:dd:d9:dd:c25:c25:94de:8649
752c19:dd:d9:dd:c25:c25:94de:864a/1282c19:dd:d9:dd:c25:c25:94de:864a
762c19:dd:d9:dd:c25:c25:94de:864b/1282c19:dd:d9:dd:c25:c25:94de:864b
772c19:dd:d9:dd:c25:c25:94de:864c/1282c19:dd:d9:dd:c25:c25:94de:864c
782c19:dd:d9:dd:c25:c25:94de:864d/1282c19:dd:d9:dd:c25:c25:94de:864d
792c19:dd:d9:dd:c25:c25:94de:864e/1282c19:dd:d9:dd:c25:c25:94de:864e
802c19:dd:d9:dd:c25:c25:94de:864f/1282c19:dd:d9:dd:c25:c25:94de:864f
812c19:dd:d9:dd:c25:c25:94de:8650/1282c19:dd:d9:dd:c25:c25:94de:8650
822c19:dd:d9:dd:c25:c25:94de:8651/1282c19:dd:d9:dd:c25:c25:94de:8651
832c19:dd:d9:dd:c25:c25:94de:8652/1282c19:dd:d9:dd:c25:c25:94de:8652
842c19:dd:d9:dd:c25:c25:94de:8653/1282c19:dd:d9:dd:c25:c25:94de:8653
852c19:dd:d9:dd:c25:c25:94de:8654/1282c19:dd:d9:dd:c25:c25:94de:8654
862c19:dd:d9:dd:c25:c25:94de:8655/1282c19:dd:d9:dd:c25:c25:94de:8655
872c19:dd:d9:dd:c25:c25:94de:8656/1282c19:dd:d9:dd:c25:c25:94de:8656
882c19:dd:d9:dd:c25:c25:94de:8657/1282c19:dd:d9:dd:c25:c25:94de:8657
892c19:dd:d9:dd:c25:c25:94de:8658/1282c19:dd:d9:dd:c25:c25:94de:8658
902c19:dd:d9:dd:c25:c25:94de:8659/1282c19:dd:d9:dd:c25:c25:94de:8659
912c19:dd:d9:dd:c25:c25:94de:865a/1282c19:dd:d9:dd:c25:c25:94de:865a
922c19:dd:d9:dd:c25:c25:94de:865b/1282c19:dd:d9:dd:c25:c25:94de:865b
932c19:dd:d9:dd:c25:c25:94de:865c/1282c19:dd:d9:dd:c25:c25:94de:865c
942c19:dd:d9:dd:c25:c25:94de:865d/1282c19:dd:d9:dd:c25:c25:94de:865d
952c19:dd:d9:dd:c25:c25:94de:865e/1282c19:dd:d9:dd:c25:c25:94de:865e
962c19:dd:d9:dd:c25:c25:94de:865f/1282c19:dd:d9:dd:c25:c25:94de:865f
972c19:dd:d9:dd:c25:c25:94de:8660/1282c19:dd:d9:dd:c25:c25:94de:8660
982c19:dd:d9:dd:c25:c25:94de:8661/1282c19:dd:d9:dd:c25:c25:94de:8661
992c19:dd:d9:dd:c25:c25:94de:8662/1282c19:dd:d9:dd:c25:c25:94de:8662
1002c19:dd:d9:dd:c25:c25:94de:8663/1282c19:dd:d9:dd:c25:c25:94de:8663
1012c19:dd:d9:dd:c25:c25:94de:8664/1282c19:dd:d9:dd:c25:c25:94de:8664
1022c19:dd:d9:dd:c25:c25:94de:8665/1282c19:dd:d9:dd:c25:c25:94de:8665
1032c19:dd:d9:dd:c25:c25:94de:8666/1282c19:dd:d9:dd:c25:c25:94de:8666
1042c19:dd:d9:dd:c25:c25:94de:8667/1282c19:dd:d9:dd:c25:c25:94de:8667
1052c19:dd:d9:dd:c25:c25:94de:8668/1282c19:dd:d9:dd:c25:c25:94de:8668
1062c19:dd:d9:dd:c25:c25:94de:8669/1282c19:dd:d9:dd:c25:c25:94de:8669
1072c19:dd:d9:dd:c25:c25:94de:866a/1282c19:dd:d9:dd:c25:c25:94de:866a
1082c19:dd:d9:dd:c25:c25:94de:866b/1282c19:dd:d9:dd:c25:c25:94de:866b
1092c19:dd:d9:dd:c25:c25:94de:866c/1282c19:dd:d9:dd:c25:c25:94de:866c
1102c19:dd:d9:dd:c25:c25:94de:866d/1282c19:dd:d9:dd:c25:c25:94de:866d
1112c19:dd:d9:dd:c25:c25:94de:866e/1282c19:dd:d9:dd:c25:c25:94de:866e
1122c19:dd:d9:dd:c25:c25:94de:866f/1282c19:dd:d9:dd:c25:c25:94de:866f
1132c19:dd:d9:dd:c25:c25:94de:8670/1282c19:dd:d9:dd:c25:c25:94de:8670
1142c19:dd:d9:dd:c25:c25:94de:8671/1282c19:dd:d9:dd:c25:c25:94de:8671
1152c19:dd:d9:dd:c25:c25:94de:8672/1282c19:dd:d9:dd:c25:c25:94de:8672
1162c19:dd:d9:dd:c25:c25:94de:8673/1282c19:dd:d9:dd:c25:c25:94de:8673
1172c19:dd:d9:dd:c25:c25:94de:8674/1282c19:dd:d9:dd:c25:c25:94de:8674
1182c19:dd:d9:dd:c25:c25:94de:8675/1282c19:dd:d9:dd:c25:c25:94de:8675
1192c19:dd:d9:dd:c25:c25:94de:8676/1282c19:dd:d9:dd:c25:c25:94de:8676
1202c19:dd:d9:dd:c25:c25:94de:8677/1282c19:dd:d9:dd:c25:c25:94de:8677
1212c19:dd:d9:dd:c25:c25:94de:8678/1282c19:dd:d9:dd:c25:c25:94de:8678
1222c19:dd:d9:dd:c25:c25:94de:8679/1282c19:dd:d9:dd:c25:c25:94de:8679
1232c19:dd:d9:dd:c25:c25:94de:867a/1282c19:dd:d9:dd:c25:c25:94de:867a
1242c19:dd:d9:dd:c25:c25:94de:867b/1282c19:dd:d9:dd:c25:c25:94de:867b
1252c19:dd:d9:dd:c25:c25:94de:867c/1282c19:dd:d9:dd:c25:c25:94de:867c
1262c19:dd:d9:dd:c25:c25:94de:867d/1282c19:dd:d9:dd:c25:c25:94de:867d
1272c19:dd:d9:dd:c25:c25:94de:867e/1282c19:dd:d9:dd:c25:c25:94de:867e
1282c19:dd:d9:dd:c25:c25:94de:867f/1282c19:dd:d9:dd:c25:c25:94de:867f
1292c19:dd:d9:dd:c25:c25:94de:8680/1282c19:dd:d9:dd:c25:c25:94de:8680
1302c19:dd:d9:dd:c25:c25:94de:8681/1282c19:dd:d9:dd:c25:c25:94de:8681
1312c19:dd:d9:dd:c25:c25:94de:8682/1282c19:dd:d9:dd:c25:c25:94de:8682
1322c19:dd:d9:dd:c25:c25:94de:8683/1282c19:dd:d9:dd:c25:c25:94de:8683
1332c19:dd:d9:dd:c25:c25:94de:8684/1282c19:dd:d9:dd:c25:c25:94de:8684
1342c19:dd:d9:dd:c25:c25:94de:8685/1282c19:dd:d9:dd:c25:c25:94de:8685
1352c19:dd:d9:dd:c25:c25:94de:8686/1282c19:dd:d9:dd:c25:c25:94de:8686
1362c19:dd:d9:dd:c25:c25:94de:8687/1282c19:dd:d9:dd:c25:c25:94de:8687
1372c19:dd:d9:dd:c25:c25:94de:8688/1282c19:dd:d9:dd:c25:c25:94de:8688
1382c19:dd:d9:dd:c25:c25:94de:8689/1282c19:dd:d9:dd:c25:c25:94de:8689
1392c19:dd:d9:dd:c25:c25:94de:868a/1282c19:dd:d9:dd:c25:c25:94de:868a
1402c19:dd:d9:dd:c25:c25:94de:868b/1282c19:dd:d9:dd:c25:c25:94de:868b
1412c19:dd:d9:dd:c25:c25:94de:868c/1282c19:dd:d9:dd:c25:c25:94de:868c
1422c19:dd:d9:dd:c25:c25:94de:868d/1282c19:dd:d9:dd:c25:c25:94de:868d
1432c19:dd:d9:dd:c25:c25:94de:868e/1282c19:dd:d9:dd:c25:c25:94de:868e
1442c19:dd:d9:dd:c25:c25:94de:868f/1282c19:dd:d9:dd:c25:c25:94de:868f
1452c19:dd:d9:dd:c25:c25:94de:8690/1282c19:dd:d9:dd:c25:c25:94de:8690
1462c19:dd:d9:dd:c25:c25:94de:8691/1282c19:dd:d9:dd:c25:c25:94de:8691
1472c19:dd:d9:dd:c25:c25:94de:8692/1282c19:dd:d9:dd:c25:c25:94de:8692
1482c19:dd:d9:dd:c25:c25:94de:8693/1282c19:dd:d9:dd:c25:c25:94de:8693
1492c19:dd:d9:dd:c25:c25:94de:8694/1282c19:dd:d9:dd:c25:c25:94de:8694
1502c19:dd:d9:dd:c25:c25:94de:8695/1282c19:dd:d9:dd:c25:c25:94de:8695
1512c19:dd:d9:dd:c25:c25:94de:8696/1282c19:dd:d9:dd:c25:c25:94de:8696
1522c19:dd:d9:dd:c25:c25:94de:8697/1282c19:dd:d9:dd:c25:c25:94de:8697
1532c19:dd:d9:dd:c25:c25:94de:8698/1282c19:dd:d9:dd:c25:c25:94de:8698
1542c19:dd:d9:dd:c25:c25:94de:8699/1282c19:dd:d9:dd:c25:c25:94de:8699
1552c19:dd:d9:dd:c25:c25:94de:869a/1282c19:dd:d9:dd:c25:c25:94de:869a
1562c19:dd:d9:dd:c25:c25:94de:869b/1282c19:dd:d9:dd:c25:c25:94de:869b
1572c19:dd:d9:dd:c25:c25:94de:869c/1282c19:dd:d9:dd:c25:c25:94de:869c
1582c19:dd:d9:dd:c25:c25:94de:869d/1282c19:dd:d9:dd:c25:c25:94de:869d
1592c19:dd:d9:dd:c25:c25:94de:869e/1282c19:dd:d9:dd:c25:c25:94de:869e
1602c19:dd:d9:dd:c25:c25:94de:869f/1282c19:dd:d9:dd:c25:c25:94de:869f
1612c19:dd:d9:dd:c25:c25:94de:86a0/1282c19:dd:d9:dd:c25:c25:94de:86a0
1622c19:dd:d9:dd:c25:c25:94de:86a1/1282c19:dd:d9:dd:c25:c25:94de:86a1
1632c19:dd:d9:dd:c25:c25:94de:86a2/1282c19:dd:d9:dd:c25:c25:94de:86a2
1642c19:dd:d9:dd:c25:c25:94de:86a3/1282c19:dd:d9:dd:c25:c25:94de:86a3
1652c19:dd:d9:dd:c25:c25:94de:86a4/1282c19:dd:d9:dd:c25:c25:94de:86a4
1662c19:dd:d9:dd:c25:c25:94de:86a5/1282c19:dd:d9:dd:c25:c25:94de:86a5
1672c19:dd:d9:dd:c25:c25:94de:86a6/1282c19:dd:d9:dd:c25:c25:94de:86a6
1682c19:dd:d9:dd:c25:c25:94de:86a7/1282c19:dd:d9:dd:c25:c25:94de:86a7
1692c19:dd:d9:dd:c25:c25:94de:86a8/1282c19:dd:d9:dd:c25:c25:94de:86a8
1702c19:dd:d9:dd:c25:c25:94de:86a9/1282c19:dd:d9:dd:c25:c25:94de:86a9
1712c19:dd:d9:dd:c25:c25:94de:86aa/1282c19:dd:d9:dd:c25:c25:94de:86aa
1722c19:dd:d9:dd:c25:c25:94de:86ab/1282c19:dd:d9:dd:c25:c25:94de:86ab
1732c19:dd:d9:dd:c25:c25:94de:86ac/1282c19:dd:d9:dd:c25:c25:94de:86ac
1742c19:dd:d9:dd:c25:c25:94de:86ad/1282c19:dd:d9:dd:c25:c25:94de:86ad
1752c19:dd:d9:dd:c25:c25:94de:86ae/1282c19:dd:d9:dd:c25:c25:94de:86ae
1762c19:dd:d9:dd:c25:c25:94de:86af/1282c19:dd:d9:dd:c25:c25:94de:86af
1772c19:dd:d9:dd:c25:c25:94de:86b0/1282c19:dd:d9:dd:c25:c25:94de:86b0
1782c19:dd:d9:dd:c25:c25:94de:86b1/1282c19:dd:d9:dd:c25:c25:94de:86b1
1792c19:dd:d9:dd:c25:c25:94de:86b2/1282c19:dd:d9:dd:c25:c25:94de:86b2
1802c19:dd:d9:dd:c25:c25:94de:86b3/1282c19:dd:d9:dd:c25:c25:94de:86b3
1812c19:dd:d9:dd:c25:c25:94de:86b4/1282c19:dd:d9:dd:c25:c25:94de:86b4
1822c19:dd:d9:dd:c25:c25:94de:86b5/1282c19:dd:d9:dd:c25:c25:94de:86b5
1832c19:dd:d9:dd:c25:c25:94de:86b6/1282c19:dd:d9:dd:c25:c25:94de:86b6
1842c19:dd:d9:dd:c25:c25:94de:86b7/1282c19:dd:d9:dd:c25:c25:94de:86b7
1852c19:dd:d9:dd:c25:c25:94de:86b8/1282c19:dd:d9:dd:c25:c25:94de:86b8
1862c19:dd:d9:dd:c25:c25:94de:86b9/1282c19:dd:d9:dd:c25:c25:94de:86b9
1872c19:dd:d9:dd:c25:c25:94de:86ba/1282c19:dd:d9:dd:c25:c25:94de:86ba
1882c19:dd:d9:dd:c25:c25:94de:86bb/1282c19:dd:d9:dd:c25:c25:94de:86bb
1892c19:dd:d9:dd:c25:c25:94de:86bc/1282c19:dd:d9:dd:c25:c25:94de:86bc
1902c19:dd:d9:dd:c25:c25:94de:86bd/1282c19:dd:d9:dd:c25:c25:94de:86bd
1912c19:dd:d9:dd:c25:c25:94de:86be/1282c19:dd:d9:dd:c25:c25:94de:86be
1922c19:dd:d9:dd:c25:c25:94de:86bf/1282c19:dd:d9:dd:c25:c25:94de:86bf
1932c19:dd:d9:dd:c25:c25:94de:86c0/1282c19:dd:d9:dd:c25:c25:94de:86c0
1942c19:dd:d9:dd:c25:c25:94de:86c1/1282c19:dd:d9:dd:c25:c25:94de:86c1
1952c19:dd:d9:dd:c25:c25:94de:86c2/1282c19:dd:d9:dd:c25:c25:94de:86c2
1962c19:dd:d9:dd:c25:c25:94de:86c3/1282c19:dd:d9:dd:c25:c25:94de:86c3
1972c19:dd:d9:dd:c25:c25:94de:86c4/1282c19:dd:d9:dd:c25:c25:94de:86c4
1982c19:dd:d9:dd:c25:c25:94de:86c5/1282c19:dd:d9:dd:c25:c25:94de:86c5
1992c19:dd:d9:dd:c25:c25:94de:86c6/1282c19:dd:d9:dd:c25:c25:94de:86c6
2002c19:dd:d9:dd:c25:c25:94de:86c7/1282c19:dd:d9:dd:c25:c25:94de:86c7
2012c19:dd:d9:dd:c25:c25:94de:86c8/1282c19:dd:d9:dd:c25:c25:94de:86c8
2022c19:dd:d9:dd:c25:c25:94de:86c9/1282c19:dd:d9:dd:c25:c25:94de:86c9
2032c19:dd:d9:dd:c25:c25:94de:86ca/1282c19:dd:d9:dd:c25:c25:94de:86ca
2042c19:dd:d9:dd:c25:c25:94de:86cb/1282c19:dd:d9:dd:c25:c25:94de:86cb
2052c19:dd:d9:dd:c25:c25:94de:86cc/1282c19:dd:d9:dd:c25:c25:94de:86cc
2062c19:dd:d9:dd:c25:c25:94de:86cd/1282c19:dd:d9:dd:c25:c25:94de:86cd
2072c19:dd:d9:dd:c25:c25:94de:86ce/1282c19:dd:d9:dd:c25:c25:94de:86ce
2082c19:dd:d9:dd:c25:c25:94de:86cf/1282c19:dd:d9:dd:c25:c25:94de:86cf
2092c19:dd:d9:dd:c25:c25:94de:86d0/1282c19:dd:d9:dd:c25:c25:94de:86d0
2102c19:dd:d9:dd:c25:c25:94de:86d1/1282c19:dd:d9:dd:c25:c25:94de:86d1
2112c19:dd:d9:dd:c25:c25:94de:86d2/1282c19:dd:d9:dd:c25:c25:94de:86d2
2122c19:dd:d9:dd:c25:c25:94de:86d3/1282c19:dd:d9:dd:c25:c25:94de:86d3
2132c19:dd:d9:dd:c25:c25:94de:86d4/1282c19:dd:d9:dd:c25:c25:94de:86d4
2142c19:dd:d9:dd:c25:c25:94de:86d5/1282c19:dd:d9:dd:c25:c25:94de:86d5
2152c19:dd:d9:dd:c25:c25:94de:86d6/1282c19:dd:d9:dd:c25:c25:94de:86d6
2162c19:dd:d9:dd:c25:c25:94de:86d7/1282c19:dd:d9:dd:c25:c25:94de:86d7
2172c19:dd:d9:dd:c25:c25:94de:86d8/1282c19:dd:d9:dd:c25:c25:94de:86d8
2182c19:dd:d9:dd:c25:c25:94de:86d9/1282c19:dd:d9:dd:c25:c25:94de:86d9
2192c19:dd:d9:dd:c25:c25:94de:86da/1282c19:dd:d9:dd:c25:c25:94de:86da
2202c19:dd:d9:dd:c25:c25:94de:86db/1282c19:dd:d9:dd:c25:c25:94de:86db
2212c19:dd:d9:dd:c25:c25:94de:86dc/1282c19:dd:d9:dd:c25:c25:94de:86dc
2222c19:dd:d9:dd:c25:c25:94de:86dd/1282c19:dd:d9:dd:c25:c25:94de:86dd
2232c19:dd:d9:dd:c25:c25:94de:86de/1282c19:dd:d9:dd:c25:c25:94de:86de
2242c19:dd:d9:dd:c25:c25:94de:86df/1282c19:dd:d9:dd:c25:c25:94de:86df
2252c19:dd:d9:dd:c25:c25:94de:86e0/1282c19:dd:d9:dd:c25:c25:94de:86e0
2262c19:dd:d9:dd:c25:c25:94de:86e1/1282c19:dd:d9:dd:c25:c25:94de:86e1
2272c19:dd:d9:dd:c25:c25:94de:86e2/1282c19:dd:d9:dd:c25:c25:94de:86e2
2282c19:dd:d9:dd:c25:c25:94de:86e3/1282c19:dd:d9:dd:c25:c25:94de:86e3
2292c19:dd:d9:dd:c25:c25:94de:86e4/1282c19:dd:d9:dd:c25:c25:94de:86e4
2302c19:dd:d9:dd:c25:c25:94de:86e5/1282c19:dd:d9:dd:c25:c25:94de:86e5
2312c19:dd:d9:dd:c25:c25:94de:86e6/1282c19:dd:d9:dd:c25:c25:94de:86e6
2322c19:dd:d9:dd:c25:c25:94de:86e7/1282c19:dd:d9:dd:c25:c25:94de:86e7
2332c19:dd:d9:dd:c25:c25:94de:86e8/1282c19:dd:d9:dd:c25:c25:94de:86e8
2342c19:dd:d9:dd:c25:c25:94de:86e9/1282c19:dd:d9:dd:c25:c25:94de:86e9
2352c19:dd:d9:dd:c25:c25:94de:86ea/1282c19:dd:d9:dd:c25:c25:94de:86ea
2362c19:dd:d9:dd:c25:c25:94de:86eb/1282c19:dd:d9:dd:c25:c25:94de:86eb
2372c19:dd:d9:dd:c25:c25:94de:86ec/1282c19:dd:d9:dd:c25:c25:94de:86ec
2382c19:dd:d9:dd:c25:c25:94de:86ed/1282c19:dd:d9:dd:c25:c25:94de:86ed
2392c19:dd:d9:dd:c25:c25:94de:86ee/1282c19:dd:d9:dd:c25:c25:94de:86ee
2402c19:dd:d9:dd:c25:c25:94de:86ef/1282c19:dd:d9:dd:c25:c25:94de:86ef
2412c19:dd:d9:dd:c25:c25:94de:86f0/1282c19:dd:d9:dd:c25:c25:94de:86f0
2422c19:dd:d9:dd:c25:c25:94de:86f1/1282c19:dd:d9:dd:c25:c25:94de:86f1
2432c19:dd:d9:dd:c25:c25:94de:86f2/1282c19:dd:d9:dd:c25:c25:94de:86f2
2442c19:dd:d9:dd:c25:c25:94de:86f3/1282c19:dd:d9:dd:c25:c25:94de:86f3
2452c19:dd:d9:dd:c25:c25:94de:86f4/1282c19:dd:d9:dd:c25:c25:94de:86f4
2462c19:dd:d9:dd:c25:c25:94de:86f5/1282c19:dd:d9:dd:c25:c25:94de:86f5
2472c19:dd:d9:dd:c25:c25:94de:86f6/1282c19:dd:d9:dd:c25:c25:94de:86f6
2482c19:dd:d9:dd:c25:c25:94de:86f7/1282c19:dd:d9:dd:c25:c25:94de:86f7
2492c19:dd:d9:dd:c25:c25:94de:86f8/1282c19:dd:d9:dd:c25:c25:94de:86f8
2502c19:dd:d9:dd:c25:c25:94de:86f9/1282c19:dd:d9:dd:c25:c25:94de:86f9
2512c19:dd:d9:dd:c25:c25:94de:86fa/1282c19:dd:d9:dd:c25:c25:94de:86fa
2522c19:dd:d9:dd:c25:c25:94de:86fb/1282c19:dd:d9:dd:c25:c25:94de:86fb
2532c19:dd:d9:dd:c25:c25:94de:86fc/1282c19:dd:d9:dd:c25:c25:94de:86fc
2542c19:dd:d9:dd:c25:c25:94de:86fd/1282c19:dd:d9:dd:c25:c25:94de:86fd
2552c19:dd:d9:dd:c25:c25:94de:86fe/1282c19:dd:d9:dd:c25:c25:94de:86fe
2562c19:dd:d9:dd:c25:c25:94de:86ff/1282c19:dd:d9:dd:c25:c25:94de:86ff

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.