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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:a500/120
First address
2c19:dd:d9:dd:c25:c25:94de:a500
Last address
2c19:dd:d9:dd:c25:c25:94de:a5ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:a500
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
5.a.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:a500/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:a500/1282c19:dd:d9:dd:c25:c25:94de:a500
22c19:dd:d9:dd:c25:c25:94de:a501/1282c19:dd:d9:dd:c25:c25:94de:a501
32c19:dd:d9:dd:c25:c25:94de:a502/1282c19:dd:d9:dd:c25:c25:94de:a502
42c19:dd:d9:dd:c25:c25:94de:a503/1282c19:dd:d9:dd:c25:c25:94de:a503
52c19:dd:d9:dd:c25:c25:94de:a504/1282c19:dd:d9:dd:c25:c25:94de:a504
62c19:dd:d9:dd:c25:c25:94de:a505/1282c19:dd:d9:dd:c25:c25:94de:a505
72c19:dd:d9:dd:c25:c25:94de:a506/1282c19:dd:d9:dd:c25:c25:94de:a506
82c19:dd:d9:dd:c25:c25:94de:a507/1282c19:dd:d9:dd:c25:c25:94de:a507
92c19:dd:d9:dd:c25:c25:94de:a508/1282c19:dd:d9:dd:c25:c25:94de:a508
102c19:dd:d9:dd:c25:c25:94de:a509/1282c19:dd:d9:dd:c25:c25:94de:a509
112c19:dd:d9:dd:c25:c25:94de:a50a/1282c19:dd:d9:dd:c25:c25:94de:a50a
122c19:dd:d9:dd:c25:c25:94de:a50b/1282c19:dd:d9:dd:c25:c25:94de:a50b
132c19:dd:d9:dd:c25:c25:94de:a50c/1282c19:dd:d9:dd:c25:c25:94de:a50c
142c19:dd:d9:dd:c25:c25:94de:a50d/1282c19:dd:d9:dd:c25:c25:94de:a50d
152c19:dd:d9:dd:c25:c25:94de:a50e/1282c19:dd:d9:dd:c25:c25:94de:a50e
162c19:dd:d9:dd:c25:c25:94de:a50f/1282c19:dd:d9:dd:c25:c25:94de:a50f
172c19:dd:d9:dd:c25:c25:94de:a510/1282c19:dd:d9:dd:c25:c25:94de:a510
182c19:dd:d9:dd:c25:c25:94de:a511/1282c19:dd:d9:dd:c25:c25:94de:a511
192c19:dd:d9:dd:c25:c25:94de:a512/1282c19:dd:d9:dd:c25:c25:94de:a512
202c19:dd:d9:dd:c25:c25:94de:a513/1282c19:dd:d9:dd:c25:c25:94de:a513
212c19:dd:d9:dd:c25:c25:94de:a514/1282c19:dd:d9:dd:c25:c25:94de:a514
222c19:dd:d9:dd:c25:c25:94de:a515/1282c19:dd:d9:dd:c25:c25:94de:a515
232c19:dd:d9:dd:c25:c25:94de:a516/1282c19:dd:d9:dd:c25:c25:94de:a516
242c19:dd:d9:dd:c25:c25:94de:a517/1282c19:dd:d9:dd:c25:c25:94de:a517
252c19:dd:d9:dd:c25:c25:94de:a518/1282c19:dd:d9:dd:c25:c25:94de:a518
262c19:dd:d9:dd:c25:c25:94de:a519/1282c19:dd:d9:dd:c25:c25:94de:a519
272c19:dd:d9:dd:c25:c25:94de:a51a/1282c19:dd:d9:dd:c25:c25:94de:a51a
282c19:dd:d9:dd:c25:c25:94de:a51b/1282c19:dd:d9:dd:c25:c25:94de:a51b
292c19:dd:d9:dd:c25:c25:94de:a51c/1282c19:dd:d9:dd:c25:c25:94de:a51c
302c19:dd:d9:dd:c25:c25:94de:a51d/1282c19:dd:d9:dd:c25:c25:94de:a51d
312c19:dd:d9:dd:c25:c25:94de:a51e/1282c19:dd:d9:dd:c25:c25:94de:a51e
322c19:dd:d9:dd:c25:c25:94de:a51f/1282c19:dd:d9:dd:c25:c25:94de:a51f
332c19:dd:d9:dd:c25:c25:94de:a520/1282c19:dd:d9:dd:c25:c25:94de:a520
342c19:dd:d9:dd:c25:c25:94de:a521/1282c19:dd:d9:dd:c25:c25:94de:a521
352c19:dd:d9:dd:c25:c25:94de:a522/1282c19:dd:d9:dd:c25:c25:94de:a522
362c19:dd:d9:dd:c25:c25:94de:a523/1282c19:dd:d9:dd:c25:c25:94de:a523
372c19:dd:d9:dd:c25:c25:94de:a524/1282c19:dd:d9:dd:c25:c25:94de:a524
382c19:dd:d9:dd:c25:c25:94de:a525/1282c19:dd:d9:dd:c25:c25:94de:a525
392c19:dd:d9:dd:c25:c25:94de:a526/1282c19:dd:d9:dd:c25:c25:94de:a526
402c19:dd:d9:dd:c25:c25:94de:a527/1282c19:dd:d9:dd:c25:c25:94de:a527
412c19:dd:d9:dd:c25:c25:94de:a528/1282c19:dd:d9:dd:c25:c25:94de:a528
422c19:dd:d9:dd:c25:c25:94de:a529/1282c19:dd:d9:dd:c25:c25:94de:a529
432c19:dd:d9:dd:c25:c25:94de:a52a/1282c19:dd:d9:dd:c25:c25:94de:a52a
442c19:dd:d9:dd:c25:c25:94de:a52b/1282c19:dd:d9:dd:c25:c25:94de:a52b
452c19:dd:d9:dd:c25:c25:94de:a52c/1282c19:dd:d9:dd:c25:c25:94de:a52c
462c19:dd:d9:dd:c25:c25:94de:a52d/1282c19:dd:d9:dd:c25:c25:94de:a52d
472c19:dd:d9:dd:c25:c25:94de:a52e/1282c19:dd:d9:dd:c25:c25:94de:a52e
482c19:dd:d9:dd:c25:c25:94de:a52f/1282c19:dd:d9:dd:c25:c25:94de:a52f
492c19:dd:d9:dd:c25:c25:94de:a530/1282c19:dd:d9:dd:c25:c25:94de:a530
502c19:dd:d9:dd:c25:c25:94de:a531/1282c19:dd:d9:dd:c25:c25:94de:a531
512c19:dd:d9:dd:c25:c25:94de:a532/1282c19:dd:d9:dd:c25:c25:94de:a532
522c19:dd:d9:dd:c25:c25:94de:a533/1282c19:dd:d9:dd:c25:c25:94de:a533
532c19:dd:d9:dd:c25:c25:94de:a534/1282c19:dd:d9:dd:c25:c25:94de:a534
542c19:dd:d9:dd:c25:c25:94de:a535/1282c19:dd:d9:dd:c25:c25:94de:a535
552c19:dd:d9:dd:c25:c25:94de:a536/1282c19:dd:d9:dd:c25:c25:94de:a536
562c19:dd:d9:dd:c25:c25:94de:a537/1282c19:dd:d9:dd:c25:c25:94de:a537
572c19:dd:d9:dd:c25:c25:94de:a538/1282c19:dd:d9:dd:c25:c25:94de:a538
582c19:dd:d9:dd:c25:c25:94de:a539/1282c19:dd:d9:dd:c25:c25:94de:a539
592c19:dd:d9:dd:c25:c25:94de:a53a/1282c19:dd:d9:dd:c25:c25:94de:a53a
602c19:dd:d9:dd:c25:c25:94de:a53b/1282c19:dd:d9:dd:c25:c25:94de:a53b
612c19:dd:d9:dd:c25:c25:94de:a53c/1282c19:dd:d9:dd:c25:c25:94de:a53c
622c19:dd:d9:dd:c25:c25:94de:a53d/1282c19:dd:d9:dd:c25:c25:94de:a53d
632c19:dd:d9:dd:c25:c25:94de:a53e/1282c19:dd:d9:dd:c25:c25:94de:a53e
642c19:dd:d9:dd:c25:c25:94de:a53f/1282c19:dd:d9:dd:c25:c25:94de:a53f
652c19:dd:d9:dd:c25:c25:94de:a540/1282c19:dd:d9:dd:c25:c25:94de:a540
662c19:dd:d9:dd:c25:c25:94de:a541/1282c19:dd:d9:dd:c25:c25:94de:a541
672c19:dd:d9:dd:c25:c25:94de:a542/1282c19:dd:d9:dd:c25:c25:94de:a542
682c19:dd:d9:dd:c25:c25:94de:a543/1282c19:dd:d9:dd:c25:c25:94de:a543
692c19:dd:d9:dd:c25:c25:94de:a544/1282c19:dd:d9:dd:c25:c25:94de:a544
702c19:dd:d9:dd:c25:c25:94de:a545/1282c19:dd:d9:dd:c25:c25:94de:a545
712c19:dd:d9:dd:c25:c25:94de:a546/1282c19:dd:d9:dd:c25:c25:94de:a546
722c19:dd:d9:dd:c25:c25:94de:a547/1282c19:dd:d9:dd:c25:c25:94de:a547
732c19:dd:d9:dd:c25:c25:94de:a548/1282c19:dd:d9:dd:c25:c25:94de:a548
742c19:dd:d9:dd:c25:c25:94de:a549/1282c19:dd:d9:dd:c25:c25:94de:a549
752c19:dd:d9:dd:c25:c25:94de:a54a/1282c19:dd:d9:dd:c25:c25:94de:a54a
762c19:dd:d9:dd:c25:c25:94de:a54b/1282c19:dd:d9:dd:c25:c25:94de:a54b
772c19:dd:d9:dd:c25:c25:94de:a54c/1282c19:dd:d9:dd:c25:c25:94de:a54c
782c19:dd:d9:dd:c25:c25:94de:a54d/1282c19:dd:d9:dd:c25:c25:94de:a54d
792c19:dd:d9:dd:c25:c25:94de:a54e/1282c19:dd:d9:dd:c25:c25:94de:a54e
802c19:dd:d9:dd:c25:c25:94de:a54f/1282c19:dd:d9:dd:c25:c25:94de:a54f
812c19:dd:d9:dd:c25:c25:94de:a550/1282c19:dd:d9:dd:c25:c25:94de:a550
822c19:dd:d9:dd:c25:c25:94de:a551/1282c19:dd:d9:dd:c25:c25:94de:a551
832c19:dd:d9:dd:c25:c25:94de:a552/1282c19:dd:d9:dd:c25:c25:94de:a552
842c19:dd:d9:dd:c25:c25:94de:a553/1282c19:dd:d9:dd:c25:c25:94de:a553
852c19:dd:d9:dd:c25:c25:94de:a554/1282c19:dd:d9:dd:c25:c25:94de:a554
862c19:dd:d9:dd:c25:c25:94de:a555/1282c19:dd:d9:dd:c25:c25:94de:a555
872c19:dd:d9:dd:c25:c25:94de:a556/1282c19:dd:d9:dd:c25:c25:94de:a556
882c19:dd:d9:dd:c25:c25:94de:a557/1282c19:dd:d9:dd:c25:c25:94de:a557
892c19:dd:d9:dd:c25:c25:94de:a558/1282c19:dd:d9:dd:c25:c25:94de:a558
902c19:dd:d9:dd:c25:c25:94de:a559/1282c19:dd:d9:dd:c25:c25:94de:a559
912c19:dd:d9:dd:c25:c25:94de:a55a/1282c19:dd:d9:dd:c25:c25:94de:a55a
922c19:dd:d9:dd:c25:c25:94de:a55b/1282c19:dd:d9:dd:c25:c25:94de:a55b
932c19:dd:d9:dd:c25:c25:94de:a55c/1282c19:dd:d9:dd:c25:c25:94de:a55c
942c19:dd:d9:dd:c25:c25:94de:a55d/1282c19:dd:d9:dd:c25:c25:94de:a55d
952c19:dd:d9:dd:c25:c25:94de:a55e/1282c19:dd:d9:dd:c25:c25:94de:a55e
962c19:dd:d9:dd:c25:c25:94de:a55f/1282c19:dd:d9:dd:c25:c25:94de:a55f
972c19:dd:d9:dd:c25:c25:94de:a560/1282c19:dd:d9:dd:c25:c25:94de:a560
982c19:dd:d9:dd:c25:c25:94de:a561/1282c19:dd:d9:dd:c25:c25:94de:a561
992c19:dd:d9:dd:c25:c25:94de:a562/1282c19:dd:d9:dd:c25:c25:94de:a562
1002c19:dd:d9:dd:c25:c25:94de:a563/1282c19:dd:d9:dd:c25:c25:94de:a563
1012c19:dd:d9:dd:c25:c25:94de:a564/1282c19:dd:d9:dd:c25:c25:94de:a564
1022c19:dd:d9:dd:c25:c25:94de:a565/1282c19:dd:d9:dd:c25:c25:94de:a565
1032c19:dd:d9:dd:c25:c25:94de:a566/1282c19:dd:d9:dd:c25:c25:94de:a566
1042c19:dd:d9:dd:c25:c25:94de:a567/1282c19:dd:d9:dd:c25:c25:94de:a567
1052c19:dd:d9:dd:c25:c25:94de:a568/1282c19:dd:d9:dd:c25:c25:94de:a568
1062c19:dd:d9:dd:c25:c25:94de:a569/1282c19:dd:d9:dd:c25:c25:94de:a569
1072c19:dd:d9:dd:c25:c25:94de:a56a/1282c19:dd:d9:dd:c25:c25:94de:a56a
1082c19:dd:d9:dd:c25:c25:94de:a56b/1282c19:dd:d9:dd:c25:c25:94de:a56b
1092c19:dd:d9:dd:c25:c25:94de:a56c/1282c19:dd:d9:dd:c25:c25:94de:a56c
1102c19:dd:d9:dd:c25:c25:94de:a56d/1282c19:dd:d9:dd:c25:c25:94de:a56d
1112c19:dd:d9:dd:c25:c25:94de:a56e/1282c19:dd:d9:dd:c25:c25:94de:a56e
1122c19:dd:d9:dd:c25:c25:94de:a56f/1282c19:dd:d9:dd:c25:c25:94de:a56f
1132c19:dd:d9:dd:c25:c25:94de:a570/1282c19:dd:d9:dd:c25:c25:94de:a570
1142c19:dd:d9:dd:c25:c25:94de:a571/1282c19:dd:d9:dd:c25:c25:94de:a571
1152c19:dd:d9:dd:c25:c25:94de:a572/1282c19:dd:d9:dd:c25:c25:94de:a572
1162c19:dd:d9:dd:c25:c25:94de:a573/1282c19:dd:d9:dd:c25:c25:94de:a573
1172c19:dd:d9:dd:c25:c25:94de:a574/1282c19:dd:d9:dd:c25:c25:94de:a574
1182c19:dd:d9:dd:c25:c25:94de:a575/1282c19:dd:d9:dd:c25:c25:94de:a575
1192c19:dd:d9:dd:c25:c25:94de:a576/1282c19:dd:d9:dd:c25:c25:94de:a576
1202c19:dd:d9:dd:c25:c25:94de:a577/1282c19:dd:d9:dd:c25:c25:94de:a577
1212c19:dd:d9:dd:c25:c25:94de:a578/1282c19:dd:d9:dd:c25:c25:94de:a578
1222c19:dd:d9:dd:c25:c25:94de:a579/1282c19:dd:d9:dd:c25:c25:94de:a579
1232c19:dd:d9:dd:c25:c25:94de:a57a/1282c19:dd:d9:dd:c25:c25:94de:a57a
1242c19:dd:d9:dd:c25:c25:94de:a57b/1282c19:dd:d9:dd:c25:c25:94de:a57b
1252c19:dd:d9:dd:c25:c25:94de:a57c/1282c19:dd:d9:dd:c25:c25:94de:a57c
1262c19:dd:d9:dd:c25:c25:94de:a57d/1282c19:dd:d9:dd:c25:c25:94de:a57d
1272c19:dd:d9:dd:c25:c25:94de:a57e/1282c19:dd:d9:dd:c25:c25:94de:a57e
1282c19:dd:d9:dd:c25:c25:94de:a57f/1282c19:dd:d9:dd:c25:c25:94de:a57f
1292c19:dd:d9:dd:c25:c25:94de:a580/1282c19:dd:d9:dd:c25:c25:94de:a580
1302c19:dd:d9:dd:c25:c25:94de:a581/1282c19:dd:d9:dd:c25:c25:94de:a581
1312c19:dd:d9:dd:c25:c25:94de:a582/1282c19:dd:d9:dd:c25:c25:94de:a582
1322c19:dd:d9:dd:c25:c25:94de:a583/1282c19:dd:d9:dd:c25:c25:94de:a583
1332c19:dd:d9:dd:c25:c25:94de:a584/1282c19:dd:d9:dd:c25:c25:94de:a584
1342c19:dd:d9:dd:c25:c25:94de:a585/1282c19:dd:d9:dd:c25:c25:94de:a585
1352c19:dd:d9:dd:c25:c25:94de:a586/1282c19:dd:d9:dd:c25:c25:94de:a586
1362c19:dd:d9:dd:c25:c25:94de:a587/1282c19:dd:d9:dd:c25:c25:94de:a587
1372c19:dd:d9:dd:c25:c25:94de:a588/1282c19:dd:d9:dd:c25:c25:94de:a588
1382c19:dd:d9:dd:c25:c25:94de:a589/1282c19:dd:d9:dd:c25:c25:94de:a589
1392c19:dd:d9:dd:c25:c25:94de:a58a/1282c19:dd:d9:dd:c25:c25:94de:a58a
1402c19:dd:d9:dd:c25:c25:94de:a58b/1282c19:dd:d9:dd:c25:c25:94de:a58b
1412c19:dd:d9:dd:c25:c25:94de:a58c/1282c19:dd:d9:dd:c25:c25:94de:a58c
1422c19:dd:d9:dd:c25:c25:94de:a58d/1282c19:dd:d9:dd:c25:c25:94de:a58d
1432c19:dd:d9:dd:c25:c25:94de:a58e/1282c19:dd:d9:dd:c25:c25:94de:a58e
1442c19:dd:d9:dd:c25:c25:94de:a58f/1282c19:dd:d9:dd:c25:c25:94de:a58f
1452c19:dd:d9:dd:c25:c25:94de:a590/1282c19:dd:d9:dd:c25:c25:94de:a590
1462c19:dd:d9:dd:c25:c25:94de:a591/1282c19:dd:d9:dd:c25:c25:94de:a591
1472c19:dd:d9:dd:c25:c25:94de:a592/1282c19:dd:d9:dd:c25:c25:94de:a592
1482c19:dd:d9:dd:c25:c25:94de:a593/1282c19:dd:d9:dd:c25:c25:94de:a593
1492c19:dd:d9:dd:c25:c25:94de:a594/1282c19:dd:d9:dd:c25:c25:94de:a594
1502c19:dd:d9:dd:c25:c25:94de:a595/1282c19:dd:d9:dd:c25:c25:94de:a595
1512c19:dd:d9:dd:c25:c25:94de:a596/1282c19:dd:d9:dd:c25:c25:94de:a596
1522c19:dd:d9:dd:c25:c25:94de:a597/1282c19:dd:d9:dd:c25:c25:94de:a597
1532c19:dd:d9:dd:c25:c25:94de:a598/1282c19:dd:d9:dd:c25:c25:94de:a598
1542c19:dd:d9:dd:c25:c25:94de:a599/1282c19:dd:d9:dd:c25:c25:94de:a599
1552c19:dd:d9:dd:c25:c25:94de:a59a/1282c19:dd:d9:dd:c25:c25:94de:a59a
1562c19:dd:d9:dd:c25:c25:94de:a59b/1282c19:dd:d9:dd:c25:c25:94de:a59b
1572c19:dd:d9:dd:c25:c25:94de:a59c/1282c19:dd:d9:dd:c25:c25:94de:a59c
1582c19:dd:d9:dd:c25:c25:94de:a59d/1282c19:dd:d9:dd:c25:c25:94de:a59d
1592c19:dd:d9:dd:c25:c25:94de:a59e/1282c19:dd:d9:dd:c25:c25:94de:a59e
1602c19:dd:d9:dd:c25:c25:94de:a59f/1282c19:dd:d9:dd:c25:c25:94de:a59f
1612c19:dd:d9:dd:c25:c25:94de:a5a0/1282c19:dd:d9:dd:c25:c25:94de:a5a0
1622c19:dd:d9:dd:c25:c25:94de:a5a1/1282c19:dd:d9:dd:c25:c25:94de:a5a1
1632c19:dd:d9:dd:c25:c25:94de:a5a2/1282c19:dd:d9:dd:c25:c25:94de:a5a2
1642c19:dd:d9:dd:c25:c25:94de:a5a3/1282c19:dd:d9:dd:c25:c25:94de:a5a3
1652c19:dd:d9:dd:c25:c25:94de:a5a4/1282c19:dd:d9:dd:c25:c25:94de:a5a4
1662c19:dd:d9:dd:c25:c25:94de:a5a5/1282c19:dd:d9:dd:c25:c25:94de:a5a5
1672c19:dd:d9:dd:c25:c25:94de:a5a6/1282c19:dd:d9:dd:c25:c25:94de:a5a6
1682c19:dd:d9:dd:c25:c25:94de:a5a7/1282c19:dd:d9:dd:c25:c25:94de:a5a7
1692c19:dd:d9:dd:c25:c25:94de:a5a8/1282c19:dd:d9:dd:c25:c25:94de:a5a8
1702c19:dd:d9:dd:c25:c25:94de:a5a9/1282c19:dd:d9:dd:c25:c25:94de:a5a9
1712c19:dd:d9:dd:c25:c25:94de:a5aa/1282c19:dd:d9:dd:c25:c25:94de:a5aa
1722c19:dd:d9:dd:c25:c25:94de:a5ab/1282c19:dd:d9:dd:c25:c25:94de:a5ab
1732c19:dd:d9:dd:c25:c25:94de:a5ac/1282c19:dd:d9:dd:c25:c25:94de:a5ac
1742c19:dd:d9:dd:c25:c25:94de:a5ad/1282c19:dd:d9:dd:c25:c25:94de:a5ad
1752c19:dd:d9:dd:c25:c25:94de:a5ae/1282c19:dd:d9:dd:c25:c25:94de:a5ae
1762c19:dd:d9:dd:c25:c25:94de:a5af/1282c19:dd:d9:dd:c25:c25:94de:a5af
1772c19:dd:d9:dd:c25:c25:94de:a5b0/1282c19:dd:d9:dd:c25:c25:94de:a5b0
1782c19:dd:d9:dd:c25:c25:94de:a5b1/1282c19:dd:d9:dd:c25:c25:94de:a5b1
1792c19:dd:d9:dd:c25:c25:94de:a5b2/1282c19:dd:d9:dd:c25:c25:94de:a5b2
1802c19:dd:d9:dd:c25:c25:94de:a5b3/1282c19:dd:d9:dd:c25:c25:94de:a5b3
1812c19:dd:d9:dd:c25:c25:94de:a5b4/1282c19:dd:d9:dd:c25:c25:94de:a5b4
1822c19:dd:d9:dd:c25:c25:94de:a5b5/1282c19:dd:d9:dd:c25:c25:94de:a5b5
1832c19:dd:d9:dd:c25:c25:94de:a5b6/1282c19:dd:d9:dd:c25:c25:94de:a5b6
1842c19:dd:d9:dd:c25:c25:94de:a5b7/1282c19:dd:d9:dd:c25:c25:94de:a5b7
1852c19:dd:d9:dd:c25:c25:94de:a5b8/1282c19:dd:d9:dd:c25:c25:94de:a5b8
1862c19:dd:d9:dd:c25:c25:94de:a5b9/1282c19:dd:d9:dd:c25:c25:94de:a5b9
1872c19:dd:d9:dd:c25:c25:94de:a5ba/1282c19:dd:d9:dd:c25:c25:94de:a5ba
1882c19:dd:d9:dd:c25:c25:94de:a5bb/1282c19:dd:d9:dd:c25:c25:94de:a5bb
1892c19:dd:d9:dd:c25:c25:94de:a5bc/1282c19:dd:d9:dd:c25:c25:94de:a5bc
1902c19:dd:d9:dd:c25:c25:94de:a5bd/1282c19:dd:d9:dd:c25:c25:94de:a5bd
1912c19:dd:d9:dd:c25:c25:94de:a5be/1282c19:dd:d9:dd:c25:c25:94de:a5be
1922c19:dd:d9:dd:c25:c25:94de:a5bf/1282c19:dd:d9:dd:c25:c25:94de:a5bf
1932c19:dd:d9:dd:c25:c25:94de:a5c0/1282c19:dd:d9:dd:c25:c25:94de:a5c0
1942c19:dd:d9:dd:c25:c25:94de:a5c1/1282c19:dd:d9:dd:c25:c25:94de:a5c1
1952c19:dd:d9:dd:c25:c25:94de:a5c2/1282c19:dd:d9:dd:c25:c25:94de:a5c2
1962c19:dd:d9:dd:c25:c25:94de:a5c3/1282c19:dd:d9:dd:c25:c25:94de:a5c3
1972c19:dd:d9:dd:c25:c25:94de:a5c4/1282c19:dd:d9:dd:c25:c25:94de:a5c4
1982c19:dd:d9:dd:c25:c25:94de:a5c5/1282c19:dd:d9:dd:c25:c25:94de:a5c5
1992c19:dd:d9:dd:c25:c25:94de:a5c6/1282c19:dd:d9:dd:c25:c25:94de:a5c6
2002c19:dd:d9:dd:c25:c25:94de:a5c7/1282c19:dd:d9:dd:c25:c25:94de:a5c7
2012c19:dd:d9:dd:c25:c25:94de:a5c8/1282c19:dd:d9:dd:c25:c25:94de:a5c8
2022c19:dd:d9:dd:c25:c25:94de:a5c9/1282c19:dd:d9:dd:c25:c25:94de:a5c9
2032c19:dd:d9:dd:c25:c25:94de:a5ca/1282c19:dd:d9:dd:c25:c25:94de:a5ca
2042c19:dd:d9:dd:c25:c25:94de:a5cb/1282c19:dd:d9:dd:c25:c25:94de:a5cb
2052c19:dd:d9:dd:c25:c25:94de:a5cc/1282c19:dd:d9:dd:c25:c25:94de:a5cc
2062c19:dd:d9:dd:c25:c25:94de:a5cd/1282c19:dd:d9:dd:c25:c25:94de:a5cd
2072c19:dd:d9:dd:c25:c25:94de:a5ce/1282c19:dd:d9:dd:c25:c25:94de:a5ce
2082c19:dd:d9:dd:c25:c25:94de:a5cf/1282c19:dd:d9:dd:c25:c25:94de:a5cf
2092c19:dd:d9:dd:c25:c25:94de:a5d0/1282c19:dd:d9:dd:c25:c25:94de:a5d0
2102c19:dd:d9:dd:c25:c25:94de:a5d1/1282c19:dd:d9:dd:c25:c25:94de:a5d1
2112c19:dd:d9:dd:c25:c25:94de:a5d2/1282c19:dd:d9:dd:c25:c25:94de:a5d2
2122c19:dd:d9:dd:c25:c25:94de:a5d3/1282c19:dd:d9:dd:c25:c25:94de:a5d3
2132c19:dd:d9:dd:c25:c25:94de:a5d4/1282c19:dd:d9:dd:c25:c25:94de:a5d4
2142c19:dd:d9:dd:c25:c25:94de:a5d5/1282c19:dd:d9:dd:c25:c25:94de:a5d5
2152c19:dd:d9:dd:c25:c25:94de:a5d6/1282c19:dd:d9:dd:c25:c25:94de:a5d6
2162c19:dd:d9:dd:c25:c25:94de:a5d7/1282c19:dd:d9:dd:c25:c25:94de:a5d7
2172c19:dd:d9:dd:c25:c25:94de:a5d8/1282c19:dd:d9:dd:c25:c25:94de:a5d8
2182c19:dd:d9:dd:c25:c25:94de:a5d9/1282c19:dd:d9:dd:c25:c25:94de:a5d9
2192c19:dd:d9:dd:c25:c25:94de:a5da/1282c19:dd:d9:dd:c25:c25:94de:a5da
2202c19:dd:d9:dd:c25:c25:94de:a5db/1282c19:dd:d9:dd:c25:c25:94de:a5db
2212c19:dd:d9:dd:c25:c25:94de:a5dc/1282c19:dd:d9:dd:c25:c25:94de:a5dc
2222c19:dd:d9:dd:c25:c25:94de:a5dd/1282c19:dd:d9:dd:c25:c25:94de:a5dd
2232c19:dd:d9:dd:c25:c25:94de:a5de/1282c19:dd:d9:dd:c25:c25:94de:a5de
2242c19:dd:d9:dd:c25:c25:94de:a5df/1282c19:dd:d9:dd:c25:c25:94de:a5df
2252c19:dd:d9:dd:c25:c25:94de:a5e0/1282c19:dd:d9:dd:c25:c25:94de:a5e0
2262c19:dd:d9:dd:c25:c25:94de:a5e1/1282c19:dd:d9:dd:c25:c25:94de:a5e1
2272c19:dd:d9:dd:c25:c25:94de:a5e2/1282c19:dd:d9:dd:c25:c25:94de:a5e2
2282c19:dd:d9:dd:c25:c25:94de:a5e3/1282c19:dd:d9:dd:c25:c25:94de:a5e3
2292c19:dd:d9:dd:c25:c25:94de:a5e4/1282c19:dd:d9:dd:c25:c25:94de:a5e4
2302c19:dd:d9:dd:c25:c25:94de:a5e5/1282c19:dd:d9:dd:c25:c25:94de:a5e5
2312c19:dd:d9:dd:c25:c25:94de:a5e6/1282c19:dd:d9:dd:c25:c25:94de:a5e6
2322c19:dd:d9:dd:c25:c25:94de:a5e7/1282c19:dd:d9:dd:c25:c25:94de:a5e7
2332c19:dd:d9:dd:c25:c25:94de:a5e8/1282c19:dd:d9:dd:c25:c25:94de:a5e8
2342c19:dd:d9:dd:c25:c25:94de:a5e9/1282c19:dd:d9:dd:c25:c25:94de:a5e9
2352c19:dd:d9:dd:c25:c25:94de:a5ea/1282c19:dd:d9:dd:c25:c25:94de:a5ea
2362c19:dd:d9:dd:c25:c25:94de:a5eb/1282c19:dd:d9:dd:c25:c25:94de:a5eb
2372c19:dd:d9:dd:c25:c25:94de:a5ec/1282c19:dd:d9:dd:c25:c25:94de:a5ec
2382c19:dd:d9:dd:c25:c25:94de:a5ed/1282c19:dd:d9:dd:c25:c25:94de:a5ed
2392c19:dd:d9:dd:c25:c25:94de:a5ee/1282c19:dd:d9:dd:c25:c25:94de:a5ee
2402c19:dd:d9:dd:c25:c25:94de:a5ef/1282c19:dd:d9:dd:c25:c25:94de:a5ef
2412c19:dd:d9:dd:c25:c25:94de:a5f0/1282c19:dd:d9:dd:c25:c25:94de:a5f0
2422c19:dd:d9:dd:c25:c25:94de:a5f1/1282c19:dd:d9:dd:c25:c25:94de:a5f1
2432c19:dd:d9:dd:c25:c25:94de:a5f2/1282c19:dd:d9:dd:c25:c25:94de:a5f2
2442c19:dd:d9:dd:c25:c25:94de:a5f3/1282c19:dd:d9:dd:c25:c25:94de:a5f3
2452c19:dd:d9:dd:c25:c25:94de:a5f4/1282c19:dd:d9:dd:c25:c25:94de:a5f4
2462c19:dd:d9:dd:c25:c25:94de:a5f5/1282c19:dd:d9:dd:c25:c25:94de:a5f5
2472c19:dd:d9:dd:c25:c25:94de:a5f6/1282c19:dd:d9:dd:c25:c25:94de:a5f6
2482c19:dd:d9:dd:c25:c25:94de:a5f7/1282c19:dd:d9:dd:c25:c25:94de:a5f7
2492c19:dd:d9:dd:c25:c25:94de:a5f8/1282c19:dd:d9:dd:c25:c25:94de:a5f8
2502c19:dd:d9:dd:c25:c25:94de:a5f9/1282c19:dd:d9:dd:c25:c25:94de:a5f9
2512c19:dd:d9:dd:c25:c25:94de:a5fa/1282c19:dd:d9:dd:c25:c25:94de:a5fa
2522c19:dd:d9:dd:c25:c25:94de:a5fb/1282c19:dd:d9:dd:c25:c25:94de:a5fb
2532c19:dd:d9:dd:c25:c25:94de:a5fc/1282c19:dd:d9:dd:c25:c25:94de:a5fc
2542c19:dd:d9:dd:c25:c25:94de:a5fd/1282c19:dd:d9:dd:c25:c25:94de:a5fd
2552c19:dd:d9:dd:c25:c25:94de:a5fe/1282c19:dd:d9:dd:c25:c25:94de:a5fe
2562c19:dd:d9:dd:c25:c25:94de:a5ff/1282c19:dd:d9:dd:c25:c25:94de:a5ff

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.