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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:7500/120
First address
2c19:dd:d9:dd:c25:c25:94de:7500
Last address
2c19:dd:d9:dd:c25:c25:94de:75ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:7500
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
5.7.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:7500/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:7500/1282c19:dd:d9:dd:c25:c25:94de:7500
22c19:dd:d9:dd:c25:c25:94de:7501/1282c19:dd:d9:dd:c25:c25:94de:7501
32c19:dd:d9:dd:c25:c25:94de:7502/1282c19:dd:d9:dd:c25:c25:94de:7502
42c19:dd:d9:dd:c25:c25:94de:7503/1282c19:dd:d9:dd:c25:c25:94de:7503
52c19:dd:d9:dd:c25:c25:94de:7504/1282c19:dd:d9:dd:c25:c25:94de:7504
62c19:dd:d9:dd:c25:c25:94de:7505/1282c19:dd:d9:dd:c25:c25:94de:7505
72c19:dd:d9:dd:c25:c25:94de:7506/1282c19:dd:d9:dd:c25:c25:94de:7506
82c19:dd:d9:dd:c25:c25:94de:7507/1282c19:dd:d9:dd:c25:c25:94de:7507
92c19:dd:d9:dd:c25:c25:94de:7508/1282c19:dd:d9:dd:c25:c25:94de:7508
102c19:dd:d9:dd:c25:c25:94de:7509/1282c19:dd:d9:dd:c25:c25:94de:7509
112c19:dd:d9:dd:c25:c25:94de:750a/1282c19:dd:d9:dd:c25:c25:94de:750a
122c19:dd:d9:dd:c25:c25:94de:750b/1282c19:dd:d9:dd:c25:c25:94de:750b
132c19:dd:d9:dd:c25:c25:94de:750c/1282c19:dd:d9:dd:c25:c25:94de:750c
142c19:dd:d9:dd:c25:c25:94de:750d/1282c19:dd:d9:dd:c25:c25:94de:750d
152c19:dd:d9:dd:c25:c25:94de:750e/1282c19:dd:d9:dd:c25:c25:94de:750e
162c19:dd:d9:dd:c25:c25:94de:750f/1282c19:dd:d9:dd:c25:c25:94de:750f
172c19:dd:d9:dd:c25:c25:94de:7510/1282c19:dd:d9:dd:c25:c25:94de:7510
182c19:dd:d9:dd:c25:c25:94de:7511/1282c19:dd:d9:dd:c25:c25:94de:7511
192c19:dd:d9:dd:c25:c25:94de:7512/1282c19:dd:d9:dd:c25:c25:94de:7512
202c19:dd:d9:dd:c25:c25:94de:7513/1282c19:dd:d9:dd:c25:c25:94de:7513
212c19:dd:d9:dd:c25:c25:94de:7514/1282c19:dd:d9:dd:c25:c25:94de:7514
222c19:dd:d9:dd:c25:c25:94de:7515/1282c19:dd:d9:dd:c25:c25:94de:7515
232c19:dd:d9:dd:c25:c25:94de:7516/1282c19:dd:d9:dd:c25:c25:94de:7516
242c19:dd:d9:dd:c25:c25:94de:7517/1282c19:dd:d9:dd:c25:c25:94de:7517
252c19:dd:d9:dd:c25:c25:94de:7518/1282c19:dd:d9:dd:c25:c25:94de:7518
262c19:dd:d9:dd:c25:c25:94de:7519/1282c19:dd:d9:dd:c25:c25:94de:7519
272c19:dd:d9:dd:c25:c25:94de:751a/1282c19:dd:d9:dd:c25:c25:94de:751a
282c19:dd:d9:dd:c25:c25:94de:751b/1282c19:dd:d9:dd:c25:c25:94de:751b
292c19:dd:d9:dd:c25:c25:94de:751c/1282c19:dd:d9:dd:c25:c25:94de:751c
302c19:dd:d9:dd:c25:c25:94de:751d/1282c19:dd:d9:dd:c25:c25:94de:751d
312c19:dd:d9:dd:c25:c25:94de:751e/1282c19:dd:d9:dd:c25:c25:94de:751e
322c19:dd:d9:dd:c25:c25:94de:751f/1282c19:dd:d9:dd:c25:c25:94de:751f
332c19:dd:d9:dd:c25:c25:94de:7520/1282c19:dd:d9:dd:c25:c25:94de:7520
342c19:dd:d9:dd:c25:c25:94de:7521/1282c19:dd:d9:dd:c25:c25:94de:7521
352c19:dd:d9:dd:c25:c25:94de:7522/1282c19:dd:d9:dd:c25:c25:94de:7522
362c19:dd:d9:dd:c25:c25:94de:7523/1282c19:dd:d9:dd:c25:c25:94de:7523
372c19:dd:d9:dd:c25:c25:94de:7524/1282c19:dd:d9:dd:c25:c25:94de:7524
382c19:dd:d9:dd:c25:c25:94de:7525/1282c19:dd:d9:dd:c25:c25:94de:7525
392c19:dd:d9:dd:c25:c25:94de:7526/1282c19:dd:d9:dd:c25:c25:94de:7526
402c19:dd:d9:dd:c25:c25:94de:7527/1282c19:dd:d9:dd:c25:c25:94de:7527
412c19:dd:d9:dd:c25:c25:94de:7528/1282c19:dd:d9:dd:c25:c25:94de:7528
422c19:dd:d9:dd:c25:c25:94de:7529/1282c19:dd:d9:dd:c25:c25:94de:7529
432c19:dd:d9:dd:c25:c25:94de:752a/1282c19:dd:d9:dd:c25:c25:94de:752a
442c19:dd:d9:dd:c25:c25:94de:752b/1282c19:dd:d9:dd:c25:c25:94de:752b
452c19:dd:d9:dd:c25:c25:94de:752c/1282c19:dd:d9:dd:c25:c25:94de:752c
462c19:dd:d9:dd:c25:c25:94de:752d/1282c19:dd:d9:dd:c25:c25:94de:752d
472c19:dd:d9:dd:c25:c25:94de:752e/1282c19:dd:d9:dd:c25:c25:94de:752e
482c19:dd:d9:dd:c25:c25:94de:752f/1282c19:dd:d9:dd:c25:c25:94de:752f
492c19:dd:d9:dd:c25:c25:94de:7530/1282c19:dd:d9:dd:c25:c25:94de:7530
502c19:dd:d9:dd:c25:c25:94de:7531/1282c19:dd:d9:dd:c25:c25:94de:7531
512c19:dd:d9:dd:c25:c25:94de:7532/1282c19:dd:d9:dd:c25:c25:94de:7532
522c19:dd:d9:dd:c25:c25:94de:7533/1282c19:dd:d9:dd:c25:c25:94de:7533
532c19:dd:d9:dd:c25:c25:94de:7534/1282c19:dd:d9:dd:c25:c25:94de:7534
542c19:dd:d9:dd:c25:c25:94de:7535/1282c19:dd:d9:dd:c25:c25:94de:7535
552c19:dd:d9:dd:c25:c25:94de:7536/1282c19:dd:d9:dd:c25:c25:94de:7536
562c19:dd:d9:dd:c25:c25:94de:7537/1282c19:dd:d9:dd:c25:c25:94de:7537
572c19:dd:d9:dd:c25:c25:94de:7538/1282c19:dd:d9:dd:c25:c25:94de:7538
582c19:dd:d9:dd:c25:c25:94de:7539/1282c19:dd:d9:dd:c25:c25:94de:7539
592c19:dd:d9:dd:c25:c25:94de:753a/1282c19:dd:d9:dd:c25:c25:94de:753a
602c19:dd:d9:dd:c25:c25:94de:753b/1282c19:dd:d9:dd:c25:c25:94de:753b
612c19:dd:d9:dd:c25:c25:94de:753c/1282c19:dd:d9:dd:c25:c25:94de:753c
622c19:dd:d9:dd:c25:c25:94de:753d/1282c19:dd:d9:dd:c25:c25:94de:753d
632c19:dd:d9:dd:c25:c25:94de:753e/1282c19:dd:d9:dd:c25:c25:94de:753e
642c19:dd:d9:dd:c25:c25:94de:753f/1282c19:dd:d9:dd:c25:c25:94de:753f
652c19:dd:d9:dd:c25:c25:94de:7540/1282c19:dd:d9:dd:c25:c25:94de:7540
662c19:dd:d9:dd:c25:c25:94de:7541/1282c19:dd:d9:dd:c25:c25:94de:7541
672c19:dd:d9:dd:c25:c25:94de:7542/1282c19:dd:d9:dd:c25:c25:94de:7542
682c19:dd:d9:dd:c25:c25:94de:7543/1282c19:dd:d9:dd:c25:c25:94de:7543
692c19:dd:d9:dd:c25:c25:94de:7544/1282c19:dd:d9:dd:c25:c25:94de:7544
702c19:dd:d9:dd:c25:c25:94de:7545/1282c19:dd:d9:dd:c25:c25:94de:7545
712c19:dd:d9:dd:c25:c25:94de:7546/1282c19:dd:d9:dd:c25:c25:94de:7546
722c19:dd:d9:dd:c25:c25:94de:7547/1282c19:dd:d9:dd:c25:c25:94de:7547
732c19:dd:d9:dd:c25:c25:94de:7548/1282c19:dd:d9:dd:c25:c25:94de:7548
742c19:dd:d9:dd:c25:c25:94de:7549/1282c19:dd:d9:dd:c25:c25:94de:7549
752c19:dd:d9:dd:c25:c25:94de:754a/1282c19:dd:d9:dd:c25:c25:94de:754a
762c19:dd:d9:dd:c25:c25:94de:754b/1282c19:dd:d9:dd:c25:c25:94de:754b
772c19:dd:d9:dd:c25:c25:94de:754c/1282c19:dd:d9:dd:c25:c25:94de:754c
782c19:dd:d9:dd:c25:c25:94de:754d/1282c19:dd:d9:dd:c25:c25:94de:754d
792c19:dd:d9:dd:c25:c25:94de:754e/1282c19:dd:d9:dd:c25:c25:94de:754e
802c19:dd:d9:dd:c25:c25:94de:754f/1282c19:dd:d9:dd:c25:c25:94de:754f
812c19:dd:d9:dd:c25:c25:94de:7550/1282c19:dd:d9:dd:c25:c25:94de:7550
822c19:dd:d9:dd:c25:c25:94de:7551/1282c19:dd:d9:dd:c25:c25:94de:7551
832c19:dd:d9:dd:c25:c25:94de:7552/1282c19:dd:d9:dd:c25:c25:94de:7552
842c19:dd:d9:dd:c25:c25:94de:7553/1282c19:dd:d9:dd:c25:c25:94de:7553
852c19:dd:d9:dd:c25:c25:94de:7554/1282c19:dd:d9:dd:c25:c25:94de:7554
862c19:dd:d9:dd:c25:c25:94de:7555/1282c19:dd:d9:dd:c25:c25:94de:7555
872c19:dd:d9:dd:c25:c25:94de:7556/1282c19:dd:d9:dd:c25:c25:94de:7556
882c19:dd:d9:dd:c25:c25:94de:7557/1282c19:dd:d9:dd:c25:c25:94de:7557
892c19:dd:d9:dd:c25:c25:94de:7558/1282c19:dd:d9:dd:c25:c25:94de:7558
902c19:dd:d9:dd:c25:c25:94de:7559/1282c19:dd:d9:dd:c25:c25:94de:7559
912c19:dd:d9:dd:c25:c25:94de:755a/1282c19:dd:d9:dd:c25:c25:94de:755a
922c19:dd:d9:dd:c25:c25:94de:755b/1282c19:dd:d9:dd:c25:c25:94de:755b
932c19:dd:d9:dd:c25:c25:94de:755c/1282c19:dd:d9:dd:c25:c25:94de:755c
942c19:dd:d9:dd:c25:c25:94de:755d/1282c19:dd:d9:dd:c25:c25:94de:755d
952c19:dd:d9:dd:c25:c25:94de:755e/1282c19:dd:d9:dd:c25:c25:94de:755e
962c19:dd:d9:dd:c25:c25:94de:755f/1282c19:dd:d9:dd:c25:c25:94de:755f
972c19:dd:d9:dd:c25:c25:94de:7560/1282c19:dd:d9:dd:c25:c25:94de:7560
982c19:dd:d9:dd:c25:c25:94de:7561/1282c19:dd:d9:dd:c25:c25:94de:7561
992c19:dd:d9:dd:c25:c25:94de:7562/1282c19:dd:d9:dd:c25:c25:94de:7562
1002c19:dd:d9:dd:c25:c25:94de:7563/1282c19:dd:d9:dd:c25:c25:94de:7563
1012c19:dd:d9:dd:c25:c25:94de:7564/1282c19:dd:d9:dd:c25:c25:94de:7564
1022c19:dd:d9:dd:c25:c25:94de:7565/1282c19:dd:d9:dd:c25:c25:94de:7565
1032c19:dd:d9:dd:c25:c25:94de:7566/1282c19:dd:d9:dd:c25:c25:94de:7566
1042c19:dd:d9:dd:c25:c25:94de:7567/1282c19:dd:d9:dd:c25:c25:94de:7567
1052c19:dd:d9:dd:c25:c25:94de:7568/1282c19:dd:d9:dd:c25:c25:94de:7568
1062c19:dd:d9:dd:c25:c25:94de:7569/1282c19:dd:d9:dd:c25:c25:94de:7569
1072c19:dd:d9:dd:c25:c25:94de:756a/1282c19:dd:d9:dd:c25:c25:94de:756a
1082c19:dd:d9:dd:c25:c25:94de:756b/1282c19:dd:d9:dd:c25:c25:94de:756b
1092c19:dd:d9:dd:c25:c25:94de:756c/1282c19:dd:d9:dd:c25:c25:94de:756c
1102c19:dd:d9:dd:c25:c25:94de:756d/1282c19:dd:d9:dd:c25:c25:94de:756d
1112c19:dd:d9:dd:c25:c25:94de:756e/1282c19:dd:d9:dd:c25:c25:94de:756e
1122c19:dd:d9:dd:c25:c25:94de:756f/1282c19:dd:d9:dd:c25:c25:94de:756f
1132c19:dd:d9:dd:c25:c25:94de:7570/1282c19:dd:d9:dd:c25:c25:94de:7570
1142c19:dd:d9:dd:c25:c25:94de:7571/1282c19:dd:d9:dd:c25:c25:94de:7571
1152c19:dd:d9:dd:c25:c25:94de:7572/1282c19:dd:d9:dd:c25:c25:94de:7572
1162c19:dd:d9:dd:c25:c25:94de:7573/1282c19:dd:d9:dd:c25:c25:94de:7573
1172c19:dd:d9:dd:c25:c25:94de:7574/1282c19:dd:d9:dd:c25:c25:94de:7574
1182c19:dd:d9:dd:c25:c25:94de:7575/1282c19:dd:d9:dd:c25:c25:94de:7575
1192c19:dd:d9:dd:c25:c25:94de:7576/1282c19:dd:d9:dd:c25:c25:94de:7576
1202c19:dd:d9:dd:c25:c25:94de:7577/1282c19:dd:d9:dd:c25:c25:94de:7577
1212c19:dd:d9:dd:c25:c25:94de:7578/1282c19:dd:d9:dd:c25:c25:94de:7578
1222c19:dd:d9:dd:c25:c25:94de:7579/1282c19:dd:d9:dd:c25:c25:94de:7579
1232c19:dd:d9:dd:c25:c25:94de:757a/1282c19:dd:d9:dd:c25:c25:94de:757a
1242c19:dd:d9:dd:c25:c25:94de:757b/1282c19:dd:d9:dd:c25:c25:94de:757b
1252c19:dd:d9:dd:c25:c25:94de:757c/1282c19:dd:d9:dd:c25:c25:94de:757c
1262c19:dd:d9:dd:c25:c25:94de:757d/1282c19:dd:d9:dd:c25:c25:94de:757d
1272c19:dd:d9:dd:c25:c25:94de:757e/1282c19:dd:d9:dd:c25:c25:94de:757e
1282c19:dd:d9:dd:c25:c25:94de:757f/1282c19:dd:d9:dd:c25:c25:94de:757f
1292c19:dd:d9:dd:c25:c25:94de:7580/1282c19:dd:d9:dd:c25:c25:94de:7580
1302c19:dd:d9:dd:c25:c25:94de:7581/1282c19:dd:d9:dd:c25:c25:94de:7581
1312c19:dd:d9:dd:c25:c25:94de:7582/1282c19:dd:d9:dd:c25:c25:94de:7582
1322c19:dd:d9:dd:c25:c25:94de:7583/1282c19:dd:d9:dd:c25:c25:94de:7583
1332c19:dd:d9:dd:c25:c25:94de:7584/1282c19:dd:d9:dd:c25:c25:94de:7584
1342c19:dd:d9:dd:c25:c25:94de:7585/1282c19:dd:d9:dd:c25:c25:94de:7585
1352c19:dd:d9:dd:c25:c25:94de:7586/1282c19:dd:d9:dd:c25:c25:94de:7586
1362c19:dd:d9:dd:c25:c25:94de:7587/1282c19:dd:d9:dd:c25:c25:94de:7587
1372c19:dd:d9:dd:c25:c25:94de:7588/1282c19:dd:d9:dd:c25:c25:94de:7588
1382c19:dd:d9:dd:c25:c25:94de:7589/1282c19:dd:d9:dd:c25:c25:94de:7589
1392c19:dd:d9:dd:c25:c25:94de:758a/1282c19:dd:d9:dd:c25:c25:94de:758a
1402c19:dd:d9:dd:c25:c25:94de:758b/1282c19:dd:d9:dd:c25:c25:94de:758b
1412c19:dd:d9:dd:c25:c25:94de:758c/1282c19:dd:d9:dd:c25:c25:94de:758c
1422c19:dd:d9:dd:c25:c25:94de:758d/1282c19:dd:d9:dd:c25:c25:94de:758d
1432c19:dd:d9:dd:c25:c25:94de:758e/1282c19:dd:d9:dd:c25:c25:94de:758e
1442c19:dd:d9:dd:c25:c25:94de:758f/1282c19:dd:d9:dd:c25:c25:94de:758f
1452c19:dd:d9:dd:c25:c25:94de:7590/1282c19:dd:d9:dd:c25:c25:94de:7590
1462c19:dd:d9:dd:c25:c25:94de:7591/1282c19:dd:d9:dd:c25:c25:94de:7591
1472c19:dd:d9:dd:c25:c25:94de:7592/1282c19:dd:d9:dd:c25:c25:94de:7592
1482c19:dd:d9:dd:c25:c25:94de:7593/1282c19:dd:d9:dd:c25:c25:94de:7593
1492c19:dd:d9:dd:c25:c25:94de:7594/1282c19:dd:d9:dd:c25:c25:94de:7594
1502c19:dd:d9:dd:c25:c25:94de:7595/1282c19:dd:d9:dd:c25:c25:94de:7595
1512c19:dd:d9:dd:c25:c25:94de:7596/1282c19:dd:d9:dd:c25:c25:94de:7596
1522c19:dd:d9:dd:c25:c25:94de:7597/1282c19:dd:d9:dd:c25:c25:94de:7597
1532c19:dd:d9:dd:c25:c25:94de:7598/1282c19:dd:d9:dd:c25:c25:94de:7598
1542c19:dd:d9:dd:c25:c25:94de:7599/1282c19:dd:d9:dd:c25:c25:94de:7599
1552c19:dd:d9:dd:c25:c25:94de:759a/1282c19:dd:d9:dd:c25:c25:94de:759a
1562c19:dd:d9:dd:c25:c25:94de:759b/1282c19:dd:d9:dd:c25:c25:94de:759b
1572c19:dd:d9:dd:c25:c25:94de:759c/1282c19:dd:d9:dd:c25:c25:94de:759c
1582c19:dd:d9:dd:c25:c25:94de:759d/1282c19:dd:d9:dd:c25:c25:94de:759d
1592c19:dd:d9:dd:c25:c25:94de:759e/1282c19:dd:d9:dd:c25:c25:94de:759e
1602c19:dd:d9:dd:c25:c25:94de:759f/1282c19:dd:d9:dd:c25:c25:94de:759f
1612c19:dd:d9:dd:c25:c25:94de:75a0/1282c19:dd:d9:dd:c25:c25:94de:75a0
1622c19:dd:d9:dd:c25:c25:94de:75a1/1282c19:dd:d9:dd:c25:c25:94de:75a1
1632c19:dd:d9:dd:c25:c25:94de:75a2/1282c19:dd:d9:dd:c25:c25:94de:75a2
1642c19:dd:d9:dd:c25:c25:94de:75a3/1282c19:dd:d9:dd:c25:c25:94de:75a3
1652c19:dd:d9:dd:c25:c25:94de:75a4/1282c19:dd:d9:dd:c25:c25:94de:75a4
1662c19:dd:d9:dd:c25:c25:94de:75a5/1282c19:dd:d9:dd:c25:c25:94de:75a5
1672c19:dd:d9:dd:c25:c25:94de:75a6/1282c19:dd:d9:dd:c25:c25:94de:75a6
1682c19:dd:d9:dd:c25:c25:94de:75a7/1282c19:dd:d9:dd:c25:c25:94de:75a7
1692c19:dd:d9:dd:c25:c25:94de:75a8/1282c19:dd:d9:dd:c25:c25:94de:75a8
1702c19:dd:d9:dd:c25:c25:94de:75a9/1282c19:dd:d9:dd:c25:c25:94de:75a9
1712c19:dd:d9:dd:c25:c25:94de:75aa/1282c19:dd:d9:dd:c25:c25:94de:75aa
1722c19:dd:d9:dd:c25:c25:94de:75ab/1282c19:dd:d9:dd:c25:c25:94de:75ab
1732c19:dd:d9:dd:c25:c25:94de:75ac/1282c19:dd:d9:dd:c25:c25:94de:75ac
1742c19:dd:d9:dd:c25:c25:94de:75ad/1282c19:dd:d9:dd:c25:c25:94de:75ad
1752c19:dd:d9:dd:c25:c25:94de:75ae/1282c19:dd:d9:dd:c25:c25:94de:75ae
1762c19:dd:d9:dd:c25:c25:94de:75af/1282c19:dd:d9:dd:c25:c25:94de:75af
1772c19:dd:d9:dd:c25:c25:94de:75b0/1282c19:dd:d9:dd:c25:c25:94de:75b0
1782c19:dd:d9:dd:c25:c25:94de:75b1/1282c19:dd:d9:dd:c25:c25:94de:75b1
1792c19:dd:d9:dd:c25:c25:94de:75b2/1282c19:dd:d9:dd:c25:c25:94de:75b2
1802c19:dd:d9:dd:c25:c25:94de:75b3/1282c19:dd:d9:dd:c25:c25:94de:75b3
1812c19:dd:d9:dd:c25:c25:94de:75b4/1282c19:dd:d9:dd:c25:c25:94de:75b4
1822c19:dd:d9:dd:c25:c25:94de:75b5/1282c19:dd:d9:dd:c25:c25:94de:75b5
1832c19:dd:d9:dd:c25:c25:94de:75b6/1282c19:dd:d9:dd:c25:c25:94de:75b6
1842c19:dd:d9:dd:c25:c25:94de:75b7/1282c19:dd:d9:dd:c25:c25:94de:75b7
1852c19:dd:d9:dd:c25:c25:94de:75b8/1282c19:dd:d9:dd:c25:c25:94de:75b8
1862c19:dd:d9:dd:c25:c25:94de:75b9/1282c19:dd:d9:dd:c25:c25:94de:75b9
1872c19:dd:d9:dd:c25:c25:94de:75ba/1282c19:dd:d9:dd:c25:c25:94de:75ba
1882c19:dd:d9:dd:c25:c25:94de:75bb/1282c19:dd:d9:dd:c25:c25:94de:75bb
1892c19:dd:d9:dd:c25:c25:94de:75bc/1282c19:dd:d9:dd:c25:c25:94de:75bc
1902c19:dd:d9:dd:c25:c25:94de:75bd/1282c19:dd:d9:dd:c25:c25:94de:75bd
1912c19:dd:d9:dd:c25:c25:94de:75be/1282c19:dd:d9:dd:c25:c25:94de:75be
1922c19:dd:d9:dd:c25:c25:94de:75bf/1282c19:dd:d9:dd:c25:c25:94de:75bf
1932c19:dd:d9:dd:c25:c25:94de:75c0/1282c19:dd:d9:dd:c25:c25:94de:75c0
1942c19:dd:d9:dd:c25:c25:94de:75c1/1282c19:dd:d9:dd:c25:c25:94de:75c1
1952c19:dd:d9:dd:c25:c25:94de:75c2/1282c19:dd:d9:dd:c25:c25:94de:75c2
1962c19:dd:d9:dd:c25:c25:94de:75c3/1282c19:dd:d9:dd:c25:c25:94de:75c3
1972c19:dd:d9:dd:c25:c25:94de:75c4/1282c19:dd:d9:dd:c25:c25:94de:75c4
1982c19:dd:d9:dd:c25:c25:94de:75c5/1282c19:dd:d9:dd:c25:c25:94de:75c5
1992c19:dd:d9:dd:c25:c25:94de:75c6/1282c19:dd:d9:dd:c25:c25:94de:75c6
2002c19:dd:d9:dd:c25:c25:94de:75c7/1282c19:dd:d9:dd:c25:c25:94de:75c7
2012c19:dd:d9:dd:c25:c25:94de:75c8/1282c19:dd:d9:dd:c25:c25:94de:75c8
2022c19:dd:d9:dd:c25:c25:94de:75c9/1282c19:dd:d9:dd:c25:c25:94de:75c9
2032c19:dd:d9:dd:c25:c25:94de:75ca/1282c19:dd:d9:dd:c25:c25:94de:75ca
2042c19:dd:d9:dd:c25:c25:94de:75cb/1282c19:dd:d9:dd:c25:c25:94de:75cb
2052c19:dd:d9:dd:c25:c25:94de:75cc/1282c19:dd:d9:dd:c25:c25:94de:75cc
2062c19:dd:d9:dd:c25:c25:94de:75cd/1282c19:dd:d9:dd:c25:c25:94de:75cd
2072c19:dd:d9:dd:c25:c25:94de:75ce/1282c19:dd:d9:dd:c25:c25:94de:75ce
2082c19:dd:d9:dd:c25:c25:94de:75cf/1282c19:dd:d9:dd:c25:c25:94de:75cf
2092c19:dd:d9:dd:c25:c25:94de:75d0/1282c19:dd:d9:dd:c25:c25:94de:75d0
2102c19:dd:d9:dd:c25:c25:94de:75d1/1282c19:dd:d9:dd:c25:c25:94de:75d1
2112c19:dd:d9:dd:c25:c25:94de:75d2/1282c19:dd:d9:dd:c25:c25:94de:75d2
2122c19:dd:d9:dd:c25:c25:94de:75d3/1282c19:dd:d9:dd:c25:c25:94de:75d3
2132c19:dd:d9:dd:c25:c25:94de:75d4/1282c19:dd:d9:dd:c25:c25:94de:75d4
2142c19:dd:d9:dd:c25:c25:94de:75d5/1282c19:dd:d9:dd:c25:c25:94de:75d5
2152c19:dd:d9:dd:c25:c25:94de:75d6/1282c19:dd:d9:dd:c25:c25:94de:75d6
2162c19:dd:d9:dd:c25:c25:94de:75d7/1282c19:dd:d9:dd:c25:c25:94de:75d7
2172c19:dd:d9:dd:c25:c25:94de:75d8/1282c19:dd:d9:dd:c25:c25:94de:75d8
2182c19:dd:d9:dd:c25:c25:94de:75d9/1282c19:dd:d9:dd:c25:c25:94de:75d9
2192c19:dd:d9:dd:c25:c25:94de:75da/1282c19:dd:d9:dd:c25:c25:94de:75da
2202c19:dd:d9:dd:c25:c25:94de:75db/1282c19:dd:d9:dd:c25:c25:94de:75db
2212c19:dd:d9:dd:c25:c25:94de:75dc/1282c19:dd:d9:dd:c25:c25:94de:75dc
2222c19:dd:d9:dd:c25:c25:94de:75dd/1282c19:dd:d9:dd:c25:c25:94de:75dd
2232c19:dd:d9:dd:c25:c25:94de:75de/1282c19:dd:d9:dd:c25:c25:94de:75de
2242c19:dd:d9:dd:c25:c25:94de:75df/1282c19:dd:d9:dd:c25:c25:94de:75df
2252c19:dd:d9:dd:c25:c25:94de:75e0/1282c19:dd:d9:dd:c25:c25:94de:75e0
2262c19:dd:d9:dd:c25:c25:94de:75e1/1282c19:dd:d9:dd:c25:c25:94de:75e1
2272c19:dd:d9:dd:c25:c25:94de:75e2/1282c19:dd:d9:dd:c25:c25:94de:75e2
2282c19:dd:d9:dd:c25:c25:94de:75e3/1282c19:dd:d9:dd:c25:c25:94de:75e3
2292c19:dd:d9:dd:c25:c25:94de:75e4/1282c19:dd:d9:dd:c25:c25:94de:75e4
2302c19:dd:d9:dd:c25:c25:94de:75e5/1282c19:dd:d9:dd:c25:c25:94de:75e5
2312c19:dd:d9:dd:c25:c25:94de:75e6/1282c19:dd:d9:dd:c25:c25:94de:75e6
2322c19:dd:d9:dd:c25:c25:94de:75e7/1282c19:dd:d9:dd:c25:c25:94de:75e7
2332c19:dd:d9:dd:c25:c25:94de:75e8/1282c19:dd:d9:dd:c25:c25:94de:75e8
2342c19:dd:d9:dd:c25:c25:94de:75e9/1282c19:dd:d9:dd:c25:c25:94de:75e9
2352c19:dd:d9:dd:c25:c25:94de:75ea/1282c19:dd:d9:dd:c25:c25:94de:75ea
2362c19:dd:d9:dd:c25:c25:94de:75eb/1282c19:dd:d9:dd:c25:c25:94de:75eb
2372c19:dd:d9:dd:c25:c25:94de:75ec/1282c19:dd:d9:dd:c25:c25:94de:75ec
2382c19:dd:d9:dd:c25:c25:94de:75ed/1282c19:dd:d9:dd:c25:c25:94de:75ed
2392c19:dd:d9:dd:c25:c25:94de:75ee/1282c19:dd:d9:dd:c25:c25:94de:75ee
2402c19:dd:d9:dd:c25:c25:94de:75ef/1282c19:dd:d9:dd:c25:c25:94de:75ef
2412c19:dd:d9:dd:c25:c25:94de:75f0/1282c19:dd:d9:dd:c25:c25:94de:75f0
2422c19:dd:d9:dd:c25:c25:94de:75f1/1282c19:dd:d9:dd:c25:c25:94de:75f1
2432c19:dd:d9:dd:c25:c25:94de:75f2/1282c19:dd:d9:dd:c25:c25:94de:75f2
2442c19:dd:d9:dd:c25:c25:94de:75f3/1282c19:dd:d9:dd:c25:c25:94de:75f3
2452c19:dd:d9:dd:c25:c25:94de:75f4/1282c19:dd:d9:dd:c25:c25:94de:75f4
2462c19:dd:d9:dd:c25:c25:94de:75f5/1282c19:dd:d9:dd:c25:c25:94de:75f5
2472c19:dd:d9:dd:c25:c25:94de:75f6/1282c19:dd:d9:dd:c25:c25:94de:75f6
2482c19:dd:d9:dd:c25:c25:94de:75f7/1282c19:dd:d9:dd:c25:c25:94de:75f7
2492c19:dd:d9:dd:c25:c25:94de:75f8/1282c19:dd:d9:dd:c25:c25:94de:75f8
2502c19:dd:d9:dd:c25:c25:94de:75f9/1282c19:dd:d9:dd:c25:c25:94de:75f9
2512c19:dd:d9:dd:c25:c25:94de:75fa/1282c19:dd:d9:dd:c25:c25:94de:75fa
2522c19:dd:d9:dd:c25:c25:94de:75fb/1282c19:dd:d9:dd:c25:c25:94de:75fb
2532c19:dd:d9:dd:c25:c25:94de:75fc/1282c19:dd:d9:dd:c25:c25:94de:75fc
2542c19:dd:d9:dd:c25:c25:94de:75fd/1282c19:dd:d9:dd:c25:c25:94de:75fd
2552c19:dd:d9:dd:c25:c25:94de:75fe/1282c19:dd:d9:dd:c25:c25:94de:75fe
2562c19:dd:d9:dd:c25:c25:94de:75ff/1282c19:dd:d9:dd:c25:c25:94de:75ff

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.