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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:b500/120
First address
2c19:dd:d9:dd:c25:c25:94de:b500
Last address
2c19:dd:d9:dd:c25:c25:94de:b5ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:b500
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
5.b.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:b500/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:b500/1282c19:dd:d9:dd:c25:c25:94de:b500
22c19:dd:d9:dd:c25:c25:94de:b501/1282c19:dd:d9:dd:c25:c25:94de:b501
32c19:dd:d9:dd:c25:c25:94de:b502/1282c19:dd:d9:dd:c25:c25:94de:b502
42c19:dd:d9:dd:c25:c25:94de:b503/1282c19:dd:d9:dd:c25:c25:94de:b503
52c19:dd:d9:dd:c25:c25:94de:b504/1282c19:dd:d9:dd:c25:c25:94de:b504
62c19:dd:d9:dd:c25:c25:94de:b505/1282c19:dd:d9:dd:c25:c25:94de:b505
72c19:dd:d9:dd:c25:c25:94de:b506/1282c19:dd:d9:dd:c25:c25:94de:b506
82c19:dd:d9:dd:c25:c25:94de:b507/1282c19:dd:d9:dd:c25:c25:94de:b507
92c19:dd:d9:dd:c25:c25:94de:b508/1282c19:dd:d9:dd:c25:c25:94de:b508
102c19:dd:d9:dd:c25:c25:94de:b509/1282c19:dd:d9:dd:c25:c25:94de:b509
112c19:dd:d9:dd:c25:c25:94de:b50a/1282c19:dd:d9:dd:c25:c25:94de:b50a
122c19:dd:d9:dd:c25:c25:94de:b50b/1282c19:dd:d9:dd:c25:c25:94de:b50b
132c19:dd:d9:dd:c25:c25:94de:b50c/1282c19:dd:d9:dd:c25:c25:94de:b50c
142c19:dd:d9:dd:c25:c25:94de:b50d/1282c19:dd:d9:dd:c25:c25:94de:b50d
152c19:dd:d9:dd:c25:c25:94de:b50e/1282c19:dd:d9:dd:c25:c25:94de:b50e
162c19:dd:d9:dd:c25:c25:94de:b50f/1282c19:dd:d9:dd:c25:c25:94de:b50f
172c19:dd:d9:dd:c25:c25:94de:b510/1282c19:dd:d9:dd:c25:c25:94de:b510
182c19:dd:d9:dd:c25:c25:94de:b511/1282c19:dd:d9:dd:c25:c25:94de:b511
192c19:dd:d9:dd:c25:c25:94de:b512/1282c19:dd:d9:dd:c25:c25:94de:b512
202c19:dd:d9:dd:c25:c25:94de:b513/1282c19:dd:d9:dd:c25:c25:94de:b513
212c19:dd:d9:dd:c25:c25:94de:b514/1282c19:dd:d9:dd:c25:c25:94de:b514
222c19:dd:d9:dd:c25:c25:94de:b515/1282c19:dd:d9:dd:c25:c25:94de:b515
232c19:dd:d9:dd:c25:c25:94de:b516/1282c19:dd:d9:dd:c25:c25:94de:b516
242c19:dd:d9:dd:c25:c25:94de:b517/1282c19:dd:d9:dd:c25:c25:94de:b517
252c19:dd:d9:dd:c25:c25:94de:b518/1282c19:dd:d9:dd:c25:c25:94de:b518
262c19:dd:d9:dd:c25:c25:94de:b519/1282c19:dd:d9:dd:c25:c25:94de:b519
272c19:dd:d9:dd:c25:c25:94de:b51a/1282c19:dd:d9:dd:c25:c25:94de:b51a
282c19:dd:d9:dd:c25:c25:94de:b51b/1282c19:dd:d9:dd:c25:c25:94de:b51b
292c19:dd:d9:dd:c25:c25:94de:b51c/1282c19:dd:d9:dd:c25:c25:94de:b51c
302c19:dd:d9:dd:c25:c25:94de:b51d/1282c19:dd:d9:dd:c25:c25:94de:b51d
312c19:dd:d9:dd:c25:c25:94de:b51e/1282c19:dd:d9:dd:c25:c25:94de:b51e
322c19:dd:d9:dd:c25:c25:94de:b51f/1282c19:dd:d9:dd:c25:c25:94de:b51f
332c19:dd:d9:dd:c25:c25:94de:b520/1282c19:dd:d9:dd:c25:c25:94de:b520
342c19:dd:d9:dd:c25:c25:94de:b521/1282c19:dd:d9:dd:c25:c25:94de:b521
352c19:dd:d9:dd:c25:c25:94de:b522/1282c19:dd:d9:dd:c25:c25:94de:b522
362c19:dd:d9:dd:c25:c25:94de:b523/1282c19:dd:d9:dd:c25:c25:94de:b523
372c19:dd:d9:dd:c25:c25:94de:b524/1282c19:dd:d9:dd:c25:c25:94de:b524
382c19:dd:d9:dd:c25:c25:94de:b525/1282c19:dd:d9:dd:c25:c25:94de:b525
392c19:dd:d9:dd:c25:c25:94de:b526/1282c19:dd:d9:dd:c25:c25:94de:b526
402c19:dd:d9:dd:c25:c25:94de:b527/1282c19:dd:d9:dd:c25:c25:94de:b527
412c19:dd:d9:dd:c25:c25:94de:b528/1282c19:dd:d9:dd:c25:c25:94de:b528
422c19:dd:d9:dd:c25:c25:94de:b529/1282c19:dd:d9:dd:c25:c25:94de:b529
432c19:dd:d9:dd:c25:c25:94de:b52a/1282c19:dd:d9:dd:c25:c25:94de:b52a
442c19:dd:d9:dd:c25:c25:94de:b52b/1282c19:dd:d9:dd:c25:c25:94de:b52b
452c19:dd:d9:dd:c25:c25:94de:b52c/1282c19:dd:d9:dd:c25:c25:94de:b52c
462c19:dd:d9:dd:c25:c25:94de:b52d/1282c19:dd:d9:dd:c25:c25:94de:b52d
472c19:dd:d9:dd:c25:c25:94de:b52e/1282c19:dd:d9:dd:c25:c25:94de:b52e
482c19:dd:d9:dd:c25:c25:94de:b52f/1282c19:dd:d9:dd:c25:c25:94de:b52f
492c19:dd:d9:dd:c25:c25:94de:b530/1282c19:dd:d9:dd:c25:c25:94de:b530
502c19:dd:d9:dd:c25:c25:94de:b531/1282c19:dd:d9:dd:c25:c25:94de:b531
512c19:dd:d9:dd:c25:c25:94de:b532/1282c19:dd:d9:dd:c25:c25:94de:b532
522c19:dd:d9:dd:c25:c25:94de:b533/1282c19:dd:d9:dd:c25:c25:94de:b533
532c19:dd:d9:dd:c25:c25:94de:b534/1282c19:dd:d9:dd:c25:c25:94de:b534
542c19:dd:d9:dd:c25:c25:94de:b535/1282c19:dd:d9:dd:c25:c25:94de:b535
552c19:dd:d9:dd:c25:c25:94de:b536/1282c19:dd:d9:dd:c25:c25:94de:b536
562c19:dd:d9:dd:c25:c25:94de:b537/1282c19:dd:d9:dd:c25:c25:94de:b537
572c19:dd:d9:dd:c25:c25:94de:b538/1282c19:dd:d9:dd:c25:c25:94de:b538
582c19:dd:d9:dd:c25:c25:94de:b539/1282c19:dd:d9:dd:c25:c25:94de:b539
592c19:dd:d9:dd:c25:c25:94de:b53a/1282c19:dd:d9:dd:c25:c25:94de:b53a
602c19:dd:d9:dd:c25:c25:94de:b53b/1282c19:dd:d9:dd:c25:c25:94de:b53b
612c19:dd:d9:dd:c25:c25:94de:b53c/1282c19:dd:d9:dd:c25:c25:94de:b53c
622c19:dd:d9:dd:c25:c25:94de:b53d/1282c19:dd:d9:dd:c25:c25:94de:b53d
632c19:dd:d9:dd:c25:c25:94de:b53e/1282c19:dd:d9:dd:c25:c25:94de:b53e
642c19:dd:d9:dd:c25:c25:94de:b53f/1282c19:dd:d9:dd:c25:c25:94de:b53f
652c19:dd:d9:dd:c25:c25:94de:b540/1282c19:dd:d9:dd:c25:c25:94de:b540
662c19:dd:d9:dd:c25:c25:94de:b541/1282c19:dd:d9:dd:c25:c25:94de:b541
672c19:dd:d9:dd:c25:c25:94de:b542/1282c19:dd:d9:dd:c25:c25:94de:b542
682c19:dd:d9:dd:c25:c25:94de:b543/1282c19:dd:d9:dd:c25:c25:94de:b543
692c19:dd:d9:dd:c25:c25:94de:b544/1282c19:dd:d9:dd:c25:c25:94de:b544
702c19:dd:d9:dd:c25:c25:94de:b545/1282c19:dd:d9:dd:c25:c25:94de:b545
712c19:dd:d9:dd:c25:c25:94de:b546/1282c19:dd:d9:dd:c25:c25:94de:b546
722c19:dd:d9:dd:c25:c25:94de:b547/1282c19:dd:d9:dd:c25:c25:94de:b547
732c19:dd:d9:dd:c25:c25:94de:b548/1282c19:dd:d9:dd:c25:c25:94de:b548
742c19:dd:d9:dd:c25:c25:94de:b549/1282c19:dd:d9:dd:c25:c25:94de:b549
752c19:dd:d9:dd:c25:c25:94de:b54a/1282c19:dd:d9:dd:c25:c25:94de:b54a
762c19:dd:d9:dd:c25:c25:94de:b54b/1282c19:dd:d9:dd:c25:c25:94de:b54b
772c19:dd:d9:dd:c25:c25:94de:b54c/1282c19:dd:d9:dd:c25:c25:94de:b54c
782c19:dd:d9:dd:c25:c25:94de:b54d/1282c19:dd:d9:dd:c25:c25:94de:b54d
792c19:dd:d9:dd:c25:c25:94de:b54e/1282c19:dd:d9:dd:c25:c25:94de:b54e
802c19:dd:d9:dd:c25:c25:94de:b54f/1282c19:dd:d9:dd:c25:c25:94de:b54f
812c19:dd:d9:dd:c25:c25:94de:b550/1282c19:dd:d9:dd:c25:c25:94de:b550
822c19:dd:d9:dd:c25:c25:94de:b551/1282c19:dd:d9:dd:c25:c25:94de:b551
832c19:dd:d9:dd:c25:c25:94de:b552/1282c19:dd:d9:dd:c25:c25:94de:b552
842c19:dd:d9:dd:c25:c25:94de:b553/1282c19:dd:d9:dd:c25:c25:94de:b553
852c19:dd:d9:dd:c25:c25:94de:b554/1282c19:dd:d9:dd:c25:c25:94de:b554
862c19:dd:d9:dd:c25:c25:94de:b555/1282c19:dd:d9:dd:c25:c25:94de:b555
872c19:dd:d9:dd:c25:c25:94de:b556/1282c19:dd:d9:dd:c25:c25:94de:b556
882c19:dd:d9:dd:c25:c25:94de:b557/1282c19:dd:d9:dd:c25:c25:94de:b557
892c19:dd:d9:dd:c25:c25:94de:b558/1282c19:dd:d9:dd:c25:c25:94de:b558
902c19:dd:d9:dd:c25:c25:94de:b559/1282c19:dd:d9:dd:c25:c25:94de:b559
912c19:dd:d9:dd:c25:c25:94de:b55a/1282c19:dd:d9:dd:c25:c25:94de:b55a
922c19:dd:d9:dd:c25:c25:94de:b55b/1282c19:dd:d9:dd:c25:c25:94de:b55b
932c19:dd:d9:dd:c25:c25:94de:b55c/1282c19:dd:d9:dd:c25:c25:94de:b55c
942c19:dd:d9:dd:c25:c25:94de:b55d/1282c19:dd:d9:dd:c25:c25:94de:b55d
952c19:dd:d9:dd:c25:c25:94de:b55e/1282c19:dd:d9:dd:c25:c25:94de:b55e
962c19:dd:d9:dd:c25:c25:94de:b55f/1282c19:dd:d9:dd:c25:c25:94de:b55f
972c19:dd:d9:dd:c25:c25:94de:b560/1282c19:dd:d9:dd:c25:c25:94de:b560
982c19:dd:d9:dd:c25:c25:94de:b561/1282c19:dd:d9:dd:c25:c25:94de:b561
992c19:dd:d9:dd:c25:c25:94de:b562/1282c19:dd:d9:dd:c25:c25:94de:b562
1002c19:dd:d9:dd:c25:c25:94de:b563/1282c19:dd:d9:dd:c25:c25:94de:b563
1012c19:dd:d9:dd:c25:c25:94de:b564/1282c19:dd:d9:dd:c25:c25:94de:b564
1022c19:dd:d9:dd:c25:c25:94de:b565/1282c19:dd:d9:dd:c25:c25:94de:b565
1032c19:dd:d9:dd:c25:c25:94de:b566/1282c19:dd:d9:dd:c25:c25:94de:b566
1042c19:dd:d9:dd:c25:c25:94de:b567/1282c19:dd:d9:dd:c25:c25:94de:b567
1052c19:dd:d9:dd:c25:c25:94de:b568/1282c19:dd:d9:dd:c25:c25:94de:b568
1062c19:dd:d9:dd:c25:c25:94de:b569/1282c19:dd:d9:dd:c25:c25:94de:b569
1072c19:dd:d9:dd:c25:c25:94de:b56a/1282c19:dd:d9:dd:c25:c25:94de:b56a
1082c19:dd:d9:dd:c25:c25:94de:b56b/1282c19:dd:d9:dd:c25:c25:94de:b56b
1092c19:dd:d9:dd:c25:c25:94de:b56c/1282c19:dd:d9:dd:c25:c25:94de:b56c
1102c19:dd:d9:dd:c25:c25:94de:b56d/1282c19:dd:d9:dd:c25:c25:94de:b56d
1112c19:dd:d9:dd:c25:c25:94de:b56e/1282c19:dd:d9:dd:c25:c25:94de:b56e
1122c19:dd:d9:dd:c25:c25:94de:b56f/1282c19:dd:d9:dd:c25:c25:94de:b56f
1132c19:dd:d9:dd:c25:c25:94de:b570/1282c19:dd:d9:dd:c25:c25:94de:b570
1142c19:dd:d9:dd:c25:c25:94de:b571/1282c19:dd:d9:dd:c25:c25:94de:b571
1152c19:dd:d9:dd:c25:c25:94de:b572/1282c19:dd:d9:dd:c25:c25:94de:b572
1162c19:dd:d9:dd:c25:c25:94de:b573/1282c19:dd:d9:dd:c25:c25:94de:b573
1172c19:dd:d9:dd:c25:c25:94de:b574/1282c19:dd:d9:dd:c25:c25:94de:b574
1182c19:dd:d9:dd:c25:c25:94de:b575/1282c19:dd:d9:dd:c25:c25:94de:b575
1192c19:dd:d9:dd:c25:c25:94de:b576/1282c19:dd:d9:dd:c25:c25:94de:b576
1202c19:dd:d9:dd:c25:c25:94de:b577/1282c19:dd:d9:dd:c25:c25:94de:b577
1212c19:dd:d9:dd:c25:c25:94de:b578/1282c19:dd:d9:dd:c25:c25:94de:b578
1222c19:dd:d9:dd:c25:c25:94de:b579/1282c19:dd:d9:dd:c25:c25:94de:b579
1232c19:dd:d9:dd:c25:c25:94de:b57a/1282c19:dd:d9:dd:c25:c25:94de:b57a
1242c19:dd:d9:dd:c25:c25:94de:b57b/1282c19:dd:d9:dd:c25:c25:94de:b57b
1252c19:dd:d9:dd:c25:c25:94de:b57c/1282c19:dd:d9:dd:c25:c25:94de:b57c
1262c19:dd:d9:dd:c25:c25:94de:b57d/1282c19:dd:d9:dd:c25:c25:94de:b57d
1272c19:dd:d9:dd:c25:c25:94de:b57e/1282c19:dd:d9:dd:c25:c25:94de:b57e
1282c19:dd:d9:dd:c25:c25:94de:b57f/1282c19:dd:d9:dd:c25:c25:94de:b57f
1292c19:dd:d9:dd:c25:c25:94de:b580/1282c19:dd:d9:dd:c25:c25:94de:b580
1302c19:dd:d9:dd:c25:c25:94de:b581/1282c19:dd:d9:dd:c25:c25:94de:b581
1312c19:dd:d9:dd:c25:c25:94de:b582/1282c19:dd:d9:dd:c25:c25:94de:b582
1322c19:dd:d9:dd:c25:c25:94de:b583/1282c19:dd:d9:dd:c25:c25:94de:b583
1332c19:dd:d9:dd:c25:c25:94de:b584/1282c19:dd:d9:dd:c25:c25:94de:b584
1342c19:dd:d9:dd:c25:c25:94de:b585/1282c19:dd:d9:dd:c25:c25:94de:b585
1352c19:dd:d9:dd:c25:c25:94de:b586/1282c19:dd:d9:dd:c25:c25:94de:b586
1362c19:dd:d9:dd:c25:c25:94de:b587/1282c19:dd:d9:dd:c25:c25:94de:b587
1372c19:dd:d9:dd:c25:c25:94de:b588/1282c19:dd:d9:dd:c25:c25:94de:b588
1382c19:dd:d9:dd:c25:c25:94de:b589/1282c19:dd:d9:dd:c25:c25:94de:b589
1392c19:dd:d9:dd:c25:c25:94de:b58a/1282c19:dd:d9:dd:c25:c25:94de:b58a
1402c19:dd:d9:dd:c25:c25:94de:b58b/1282c19:dd:d9:dd:c25:c25:94de:b58b
1412c19:dd:d9:dd:c25:c25:94de:b58c/1282c19:dd:d9:dd:c25:c25:94de:b58c
1422c19:dd:d9:dd:c25:c25:94de:b58d/1282c19:dd:d9:dd:c25:c25:94de:b58d
1432c19:dd:d9:dd:c25:c25:94de:b58e/1282c19:dd:d9:dd:c25:c25:94de:b58e
1442c19:dd:d9:dd:c25:c25:94de:b58f/1282c19:dd:d9:dd:c25:c25:94de:b58f
1452c19:dd:d9:dd:c25:c25:94de:b590/1282c19:dd:d9:dd:c25:c25:94de:b590
1462c19:dd:d9:dd:c25:c25:94de:b591/1282c19:dd:d9:dd:c25:c25:94de:b591
1472c19:dd:d9:dd:c25:c25:94de:b592/1282c19:dd:d9:dd:c25:c25:94de:b592
1482c19:dd:d9:dd:c25:c25:94de:b593/1282c19:dd:d9:dd:c25:c25:94de:b593
1492c19:dd:d9:dd:c25:c25:94de:b594/1282c19:dd:d9:dd:c25:c25:94de:b594
1502c19:dd:d9:dd:c25:c25:94de:b595/1282c19:dd:d9:dd:c25:c25:94de:b595
1512c19:dd:d9:dd:c25:c25:94de:b596/1282c19:dd:d9:dd:c25:c25:94de:b596
1522c19:dd:d9:dd:c25:c25:94de:b597/1282c19:dd:d9:dd:c25:c25:94de:b597
1532c19:dd:d9:dd:c25:c25:94de:b598/1282c19:dd:d9:dd:c25:c25:94de:b598
1542c19:dd:d9:dd:c25:c25:94de:b599/1282c19:dd:d9:dd:c25:c25:94de:b599
1552c19:dd:d9:dd:c25:c25:94de:b59a/1282c19:dd:d9:dd:c25:c25:94de:b59a
1562c19:dd:d9:dd:c25:c25:94de:b59b/1282c19:dd:d9:dd:c25:c25:94de:b59b
1572c19:dd:d9:dd:c25:c25:94de:b59c/1282c19:dd:d9:dd:c25:c25:94de:b59c
1582c19:dd:d9:dd:c25:c25:94de:b59d/1282c19:dd:d9:dd:c25:c25:94de:b59d
1592c19:dd:d9:dd:c25:c25:94de:b59e/1282c19:dd:d9:dd:c25:c25:94de:b59e
1602c19:dd:d9:dd:c25:c25:94de:b59f/1282c19:dd:d9:dd:c25:c25:94de:b59f
1612c19:dd:d9:dd:c25:c25:94de:b5a0/1282c19:dd:d9:dd:c25:c25:94de:b5a0
1622c19:dd:d9:dd:c25:c25:94de:b5a1/1282c19:dd:d9:dd:c25:c25:94de:b5a1
1632c19:dd:d9:dd:c25:c25:94de:b5a2/1282c19:dd:d9:dd:c25:c25:94de:b5a2
1642c19:dd:d9:dd:c25:c25:94de:b5a3/1282c19:dd:d9:dd:c25:c25:94de:b5a3
1652c19:dd:d9:dd:c25:c25:94de:b5a4/1282c19:dd:d9:dd:c25:c25:94de:b5a4
1662c19:dd:d9:dd:c25:c25:94de:b5a5/1282c19:dd:d9:dd:c25:c25:94de:b5a5
1672c19:dd:d9:dd:c25:c25:94de:b5a6/1282c19:dd:d9:dd:c25:c25:94de:b5a6
1682c19:dd:d9:dd:c25:c25:94de:b5a7/1282c19:dd:d9:dd:c25:c25:94de:b5a7
1692c19:dd:d9:dd:c25:c25:94de:b5a8/1282c19:dd:d9:dd:c25:c25:94de:b5a8
1702c19:dd:d9:dd:c25:c25:94de:b5a9/1282c19:dd:d9:dd:c25:c25:94de:b5a9
1712c19:dd:d9:dd:c25:c25:94de:b5aa/1282c19:dd:d9:dd:c25:c25:94de:b5aa
1722c19:dd:d9:dd:c25:c25:94de:b5ab/1282c19:dd:d9:dd:c25:c25:94de:b5ab
1732c19:dd:d9:dd:c25:c25:94de:b5ac/1282c19:dd:d9:dd:c25:c25:94de:b5ac
1742c19:dd:d9:dd:c25:c25:94de:b5ad/1282c19:dd:d9:dd:c25:c25:94de:b5ad
1752c19:dd:d9:dd:c25:c25:94de:b5ae/1282c19:dd:d9:dd:c25:c25:94de:b5ae
1762c19:dd:d9:dd:c25:c25:94de:b5af/1282c19:dd:d9:dd:c25:c25:94de:b5af
1772c19:dd:d9:dd:c25:c25:94de:b5b0/1282c19:dd:d9:dd:c25:c25:94de:b5b0
1782c19:dd:d9:dd:c25:c25:94de:b5b1/1282c19:dd:d9:dd:c25:c25:94de:b5b1
1792c19:dd:d9:dd:c25:c25:94de:b5b2/1282c19:dd:d9:dd:c25:c25:94de:b5b2
1802c19:dd:d9:dd:c25:c25:94de:b5b3/1282c19:dd:d9:dd:c25:c25:94de:b5b3
1812c19:dd:d9:dd:c25:c25:94de:b5b4/1282c19:dd:d9:dd:c25:c25:94de:b5b4
1822c19:dd:d9:dd:c25:c25:94de:b5b5/1282c19:dd:d9:dd:c25:c25:94de:b5b5
1832c19:dd:d9:dd:c25:c25:94de:b5b6/1282c19:dd:d9:dd:c25:c25:94de:b5b6
1842c19:dd:d9:dd:c25:c25:94de:b5b7/1282c19:dd:d9:dd:c25:c25:94de:b5b7
1852c19:dd:d9:dd:c25:c25:94de:b5b8/1282c19:dd:d9:dd:c25:c25:94de:b5b8
1862c19:dd:d9:dd:c25:c25:94de:b5b9/1282c19:dd:d9:dd:c25:c25:94de:b5b9
1872c19:dd:d9:dd:c25:c25:94de:b5ba/1282c19:dd:d9:dd:c25:c25:94de:b5ba
1882c19:dd:d9:dd:c25:c25:94de:b5bb/1282c19:dd:d9:dd:c25:c25:94de:b5bb
1892c19:dd:d9:dd:c25:c25:94de:b5bc/1282c19:dd:d9:dd:c25:c25:94de:b5bc
1902c19:dd:d9:dd:c25:c25:94de:b5bd/1282c19:dd:d9:dd:c25:c25:94de:b5bd
1912c19:dd:d9:dd:c25:c25:94de:b5be/1282c19:dd:d9:dd:c25:c25:94de:b5be
1922c19:dd:d9:dd:c25:c25:94de:b5bf/1282c19:dd:d9:dd:c25:c25:94de:b5bf
1932c19:dd:d9:dd:c25:c25:94de:b5c0/1282c19:dd:d9:dd:c25:c25:94de:b5c0
1942c19:dd:d9:dd:c25:c25:94de:b5c1/1282c19:dd:d9:dd:c25:c25:94de:b5c1
1952c19:dd:d9:dd:c25:c25:94de:b5c2/1282c19:dd:d9:dd:c25:c25:94de:b5c2
1962c19:dd:d9:dd:c25:c25:94de:b5c3/1282c19:dd:d9:dd:c25:c25:94de:b5c3
1972c19:dd:d9:dd:c25:c25:94de:b5c4/1282c19:dd:d9:dd:c25:c25:94de:b5c4
1982c19:dd:d9:dd:c25:c25:94de:b5c5/1282c19:dd:d9:dd:c25:c25:94de:b5c5
1992c19:dd:d9:dd:c25:c25:94de:b5c6/1282c19:dd:d9:dd:c25:c25:94de:b5c6
2002c19:dd:d9:dd:c25:c25:94de:b5c7/1282c19:dd:d9:dd:c25:c25:94de:b5c7
2012c19:dd:d9:dd:c25:c25:94de:b5c8/1282c19:dd:d9:dd:c25:c25:94de:b5c8
2022c19:dd:d9:dd:c25:c25:94de:b5c9/1282c19:dd:d9:dd:c25:c25:94de:b5c9
2032c19:dd:d9:dd:c25:c25:94de:b5ca/1282c19:dd:d9:dd:c25:c25:94de:b5ca
2042c19:dd:d9:dd:c25:c25:94de:b5cb/1282c19:dd:d9:dd:c25:c25:94de:b5cb
2052c19:dd:d9:dd:c25:c25:94de:b5cc/1282c19:dd:d9:dd:c25:c25:94de:b5cc
2062c19:dd:d9:dd:c25:c25:94de:b5cd/1282c19:dd:d9:dd:c25:c25:94de:b5cd
2072c19:dd:d9:dd:c25:c25:94de:b5ce/1282c19:dd:d9:dd:c25:c25:94de:b5ce
2082c19:dd:d9:dd:c25:c25:94de:b5cf/1282c19:dd:d9:dd:c25:c25:94de:b5cf
2092c19:dd:d9:dd:c25:c25:94de:b5d0/1282c19:dd:d9:dd:c25:c25:94de:b5d0
2102c19:dd:d9:dd:c25:c25:94de:b5d1/1282c19:dd:d9:dd:c25:c25:94de:b5d1
2112c19:dd:d9:dd:c25:c25:94de:b5d2/1282c19:dd:d9:dd:c25:c25:94de:b5d2
2122c19:dd:d9:dd:c25:c25:94de:b5d3/1282c19:dd:d9:dd:c25:c25:94de:b5d3
2132c19:dd:d9:dd:c25:c25:94de:b5d4/1282c19:dd:d9:dd:c25:c25:94de:b5d4
2142c19:dd:d9:dd:c25:c25:94de:b5d5/1282c19:dd:d9:dd:c25:c25:94de:b5d5
2152c19:dd:d9:dd:c25:c25:94de:b5d6/1282c19:dd:d9:dd:c25:c25:94de:b5d6
2162c19:dd:d9:dd:c25:c25:94de:b5d7/1282c19:dd:d9:dd:c25:c25:94de:b5d7
2172c19:dd:d9:dd:c25:c25:94de:b5d8/1282c19:dd:d9:dd:c25:c25:94de:b5d8
2182c19:dd:d9:dd:c25:c25:94de:b5d9/1282c19:dd:d9:dd:c25:c25:94de:b5d9
2192c19:dd:d9:dd:c25:c25:94de:b5da/1282c19:dd:d9:dd:c25:c25:94de:b5da
2202c19:dd:d9:dd:c25:c25:94de:b5db/1282c19:dd:d9:dd:c25:c25:94de:b5db
2212c19:dd:d9:dd:c25:c25:94de:b5dc/1282c19:dd:d9:dd:c25:c25:94de:b5dc
2222c19:dd:d9:dd:c25:c25:94de:b5dd/1282c19:dd:d9:dd:c25:c25:94de:b5dd
2232c19:dd:d9:dd:c25:c25:94de:b5de/1282c19:dd:d9:dd:c25:c25:94de:b5de
2242c19:dd:d9:dd:c25:c25:94de:b5df/1282c19:dd:d9:dd:c25:c25:94de:b5df
2252c19:dd:d9:dd:c25:c25:94de:b5e0/1282c19:dd:d9:dd:c25:c25:94de:b5e0
2262c19:dd:d9:dd:c25:c25:94de:b5e1/1282c19:dd:d9:dd:c25:c25:94de:b5e1
2272c19:dd:d9:dd:c25:c25:94de:b5e2/1282c19:dd:d9:dd:c25:c25:94de:b5e2
2282c19:dd:d9:dd:c25:c25:94de:b5e3/1282c19:dd:d9:dd:c25:c25:94de:b5e3
2292c19:dd:d9:dd:c25:c25:94de:b5e4/1282c19:dd:d9:dd:c25:c25:94de:b5e4
2302c19:dd:d9:dd:c25:c25:94de:b5e5/1282c19:dd:d9:dd:c25:c25:94de:b5e5
2312c19:dd:d9:dd:c25:c25:94de:b5e6/1282c19:dd:d9:dd:c25:c25:94de:b5e6
2322c19:dd:d9:dd:c25:c25:94de:b5e7/1282c19:dd:d9:dd:c25:c25:94de:b5e7
2332c19:dd:d9:dd:c25:c25:94de:b5e8/1282c19:dd:d9:dd:c25:c25:94de:b5e8
2342c19:dd:d9:dd:c25:c25:94de:b5e9/1282c19:dd:d9:dd:c25:c25:94de:b5e9
2352c19:dd:d9:dd:c25:c25:94de:b5ea/1282c19:dd:d9:dd:c25:c25:94de:b5ea
2362c19:dd:d9:dd:c25:c25:94de:b5eb/1282c19:dd:d9:dd:c25:c25:94de:b5eb
2372c19:dd:d9:dd:c25:c25:94de:b5ec/1282c19:dd:d9:dd:c25:c25:94de:b5ec
2382c19:dd:d9:dd:c25:c25:94de:b5ed/1282c19:dd:d9:dd:c25:c25:94de:b5ed
2392c19:dd:d9:dd:c25:c25:94de:b5ee/1282c19:dd:d9:dd:c25:c25:94de:b5ee
2402c19:dd:d9:dd:c25:c25:94de:b5ef/1282c19:dd:d9:dd:c25:c25:94de:b5ef
2412c19:dd:d9:dd:c25:c25:94de:b5f0/1282c19:dd:d9:dd:c25:c25:94de:b5f0
2422c19:dd:d9:dd:c25:c25:94de:b5f1/1282c19:dd:d9:dd:c25:c25:94de:b5f1
2432c19:dd:d9:dd:c25:c25:94de:b5f2/1282c19:dd:d9:dd:c25:c25:94de:b5f2
2442c19:dd:d9:dd:c25:c25:94de:b5f3/1282c19:dd:d9:dd:c25:c25:94de:b5f3
2452c19:dd:d9:dd:c25:c25:94de:b5f4/1282c19:dd:d9:dd:c25:c25:94de:b5f4
2462c19:dd:d9:dd:c25:c25:94de:b5f5/1282c19:dd:d9:dd:c25:c25:94de:b5f5
2472c19:dd:d9:dd:c25:c25:94de:b5f6/1282c19:dd:d9:dd:c25:c25:94de:b5f6
2482c19:dd:d9:dd:c25:c25:94de:b5f7/1282c19:dd:d9:dd:c25:c25:94de:b5f7
2492c19:dd:d9:dd:c25:c25:94de:b5f8/1282c19:dd:d9:dd:c25:c25:94de:b5f8
2502c19:dd:d9:dd:c25:c25:94de:b5f9/1282c19:dd:d9:dd:c25:c25:94de:b5f9
2512c19:dd:d9:dd:c25:c25:94de:b5fa/1282c19:dd:d9:dd:c25:c25:94de:b5fa
2522c19:dd:d9:dd:c25:c25:94de:b5fb/1282c19:dd:d9:dd:c25:c25:94de:b5fb
2532c19:dd:d9:dd:c25:c25:94de:b5fc/1282c19:dd:d9:dd:c25:c25:94de:b5fc
2542c19:dd:d9:dd:c25:c25:94de:b5fd/1282c19:dd:d9:dd:c25:c25:94de:b5fd
2552c19:dd:d9:dd:c25:c25:94de:b5fe/1282c19:dd:d9:dd:c25:c25:94de:b5fe
2562c19:dd:d9:dd:c25:c25:94de:b5ff/1282c19:dd:d9:dd:c25:c25:94de:b5ff

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.