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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:6400/120
First address
2c19:dd:d9:dd:c25:c25:94de:6400
Last address
2c19:dd:d9:dd:c25:c25:94de:64ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:6400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
4.6.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:6400/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:6400/1282c19:dd:d9:dd:c25:c25:94de:6400
22c19:dd:d9:dd:c25:c25:94de:6401/1282c19:dd:d9:dd:c25:c25:94de:6401
32c19:dd:d9:dd:c25:c25:94de:6402/1282c19:dd:d9:dd:c25:c25:94de:6402
42c19:dd:d9:dd:c25:c25:94de:6403/1282c19:dd:d9:dd:c25:c25:94de:6403
52c19:dd:d9:dd:c25:c25:94de:6404/1282c19:dd:d9:dd:c25:c25:94de:6404
62c19:dd:d9:dd:c25:c25:94de:6405/1282c19:dd:d9:dd:c25:c25:94de:6405
72c19:dd:d9:dd:c25:c25:94de:6406/1282c19:dd:d9:dd:c25:c25:94de:6406
82c19:dd:d9:dd:c25:c25:94de:6407/1282c19:dd:d9:dd:c25:c25:94de:6407
92c19:dd:d9:dd:c25:c25:94de:6408/1282c19:dd:d9:dd:c25:c25:94de:6408
102c19:dd:d9:dd:c25:c25:94de:6409/1282c19:dd:d9:dd:c25:c25:94de:6409
112c19:dd:d9:dd:c25:c25:94de:640a/1282c19:dd:d9:dd:c25:c25:94de:640a
122c19:dd:d9:dd:c25:c25:94de:640b/1282c19:dd:d9:dd:c25:c25:94de:640b
132c19:dd:d9:dd:c25:c25:94de:640c/1282c19:dd:d9:dd:c25:c25:94de:640c
142c19:dd:d9:dd:c25:c25:94de:640d/1282c19:dd:d9:dd:c25:c25:94de:640d
152c19:dd:d9:dd:c25:c25:94de:640e/1282c19:dd:d9:dd:c25:c25:94de:640e
162c19:dd:d9:dd:c25:c25:94de:640f/1282c19:dd:d9:dd:c25:c25:94de:640f
172c19:dd:d9:dd:c25:c25:94de:6410/1282c19:dd:d9:dd:c25:c25:94de:6410
182c19:dd:d9:dd:c25:c25:94de:6411/1282c19:dd:d9:dd:c25:c25:94de:6411
192c19:dd:d9:dd:c25:c25:94de:6412/1282c19:dd:d9:dd:c25:c25:94de:6412
202c19:dd:d9:dd:c25:c25:94de:6413/1282c19:dd:d9:dd:c25:c25:94de:6413
212c19:dd:d9:dd:c25:c25:94de:6414/1282c19:dd:d9:dd:c25:c25:94de:6414
222c19:dd:d9:dd:c25:c25:94de:6415/1282c19:dd:d9:dd:c25:c25:94de:6415
232c19:dd:d9:dd:c25:c25:94de:6416/1282c19:dd:d9:dd:c25:c25:94de:6416
242c19:dd:d9:dd:c25:c25:94de:6417/1282c19:dd:d9:dd:c25:c25:94de:6417
252c19:dd:d9:dd:c25:c25:94de:6418/1282c19:dd:d9:dd:c25:c25:94de:6418
262c19:dd:d9:dd:c25:c25:94de:6419/1282c19:dd:d9:dd:c25:c25:94de:6419
272c19:dd:d9:dd:c25:c25:94de:641a/1282c19:dd:d9:dd:c25:c25:94de:641a
282c19:dd:d9:dd:c25:c25:94de:641b/1282c19:dd:d9:dd:c25:c25:94de:641b
292c19:dd:d9:dd:c25:c25:94de:641c/1282c19:dd:d9:dd:c25:c25:94de:641c
302c19:dd:d9:dd:c25:c25:94de:641d/1282c19:dd:d9:dd:c25:c25:94de:641d
312c19:dd:d9:dd:c25:c25:94de:641e/1282c19:dd:d9:dd:c25:c25:94de:641e
322c19:dd:d9:dd:c25:c25:94de:641f/1282c19:dd:d9:dd:c25:c25:94de:641f
332c19:dd:d9:dd:c25:c25:94de:6420/1282c19:dd:d9:dd:c25:c25:94de:6420
342c19:dd:d9:dd:c25:c25:94de:6421/1282c19:dd:d9:dd:c25:c25:94de:6421
352c19:dd:d9:dd:c25:c25:94de:6422/1282c19:dd:d9:dd:c25:c25:94de:6422
362c19:dd:d9:dd:c25:c25:94de:6423/1282c19:dd:d9:dd:c25:c25:94de:6423
372c19:dd:d9:dd:c25:c25:94de:6424/1282c19:dd:d9:dd:c25:c25:94de:6424
382c19:dd:d9:dd:c25:c25:94de:6425/1282c19:dd:d9:dd:c25:c25:94de:6425
392c19:dd:d9:dd:c25:c25:94de:6426/1282c19:dd:d9:dd:c25:c25:94de:6426
402c19:dd:d9:dd:c25:c25:94de:6427/1282c19:dd:d9:dd:c25:c25:94de:6427
412c19:dd:d9:dd:c25:c25:94de:6428/1282c19:dd:d9:dd:c25:c25:94de:6428
422c19:dd:d9:dd:c25:c25:94de:6429/1282c19:dd:d9:dd:c25:c25:94de:6429
432c19:dd:d9:dd:c25:c25:94de:642a/1282c19:dd:d9:dd:c25:c25:94de:642a
442c19:dd:d9:dd:c25:c25:94de:642b/1282c19:dd:d9:dd:c25:c25:94de:642b
452c19:dd:d9:dd:c25:c25:94de:642c/1282c19:dd:d9:dd:c25:c25:94de:642c
462c19:dd:d9:dd:c25:c25:94de:642d/1282c19:dd:d9:dd:c25:c25:94de:642d
472c19:dd:d9:dd:c25:c25:94de:642e/1282c19:dd:d9:dd:c25:c25:94de:642e
482c19:dd:d9:dd:c25:c25:94de:642f/1282c19:dd:d9:dd:c25:c25:94de:642f
492c19:dd:d9:dd:c25:c25:94de:6430/1282c19:dd:d9:dd:c25:c25:94de:6430
502c19:dd:d9:dd:c25:c25:94de:6431/1282c19:dd:d9:dd:c25:c25:94de:6431
512c19:dd:d9:dd:c25:c25:94de:6432/1282c19:dd:d9:dd:c25:c25:94de:6432
522c19:dd:d9:dd:c25:c25:94de:6433/1282c19:dd:d9:dd:c25:c25:94de:6433
532c19:dd:d9:dd:c25:c25:94de:6434/1282c19:dd:d9:dd:c25:c25:94de:6434
542c19:dd:d9:dd:c25:c25:94de:6435/1282c19:dd:d9:dd:c25:c25:94de:6435
552c19:dd:d9:dd:c25:c25:94de:6436/1282c19:dd:d9:dd:c25:c25:94de:6436
562c19:dd:d9:dd:c25:c25:94de:6437/1282c19:dd:d9:dd:c25:c25:94de:6437
572c19:dd:d9:dd:c25:c25:94de:6438/1282c19:dd:d9:dd:c25:c25:94de:6438
582c19:dd:d9:dd:c25:c25:94de:6439/1282c19:dd:d9:dd:c25:c25:94de:6439
592c19:dd:d9:dd:c25:c25:94de:643a/1282c19:dd:d9:dd:c25:c25:94de:643a
602c19:dd:d9:dd:c25:c25:94de:643b/1282c19:dd:d9:dd:c25:c25:94de:643b
612c19:dd:d9:dd:c25:c25:94de:643c/1282c19:dd:d9:dd:c25:c25:94de:643c
622c19:dd:d9:dd:c25:c25:94de:643d/1282c19:dd:d9:dd:c25:c25:94de:643d
632c19:dd:d9:dd:c25:c25:94de:643e/1282c19:dd:d9:dd:c25:c25:94de:643e
642c19:dd:d9:dd:c25:c25:94de:643f/1282c19:dd:d9:dd:c25:c25:94de:643f
652c19:dd:d9:dd:c25:c25:94de:6440/1282c19:dd:d9:dd:c25:c25:94de:6440
662c19:dd:d9:dd:c25:c25:94de:6441/1282c19:dd:d9:dd:c25:c25:94de:6441
672c19:dd:d9:dd:c25:c25:94de:6442/1282c19:dd:d9:dd:c25:c25:94de:6442
682c19:dd:d9:dd:c25:c25:94de:6443/1282c19:dd:d9:dd:c25:c25:94de:6443
692c19:dd:d9:dd:c25:c25:94de:6444/1282c19:dd:d9:dd:c25:c25:94de:6444
702c19:dd:d9:dd:c25:c25:94de:6445/1282c19:dd:d9:dd:c25:c25:94de:6445
712c19:dd:d9:dd:c25:c25:94de:6446/1282c19:dd:d9:dd:c25:c25:94de:6446
722c19:dd:d9:dd:c25:c25:94de:6447/1282c19:dd:d9:dd:c25:c25:94de:6447
732c19:dd:d9:dd:c25:c25:94de:6448/1282c19:dd:d9:dd:c25:c25:94de:6448
742c19:dd:d9:dd:c25:c25:94de:6449/1282c19:dd:d9:dd:c25:c25:94de:6449
752c19:dd:d9:dd:c25:c25:94de:644a/1282c19:dd:d9:dd:c25:c25:94de:644a
762c19:dd:d9:dd:c25:c25:94de:644b/1282c19:dd:d9:dd:c25:c25:94de:644b
772c19:dd:d9:dd:c25:c25:94de:644c/1282c19:dd:d9:dd:c25:c25:94de:644c
782c19:dd:d9:dd:c25:c25:94de:644d/1282c19:dd:d9:dd:c25:c25:94de:644d
792c19:dd:d9:dd:c25:c25:94de:644e/1282c19:dd:d9:dd:c25:c25:94de:644e
802c19:dd:d9:dd:c25:c25:94de:644f/1282c19:dd:d9:dd:c25:c25:94de:644f
812c19:dd:d9:dd:c25:c25:94de:6450/1282c19:dd:d9:dd:c25:c25:94de:6450
822c19:dd:d9:dd:c25:c25:94de:6451/1282c19:dd:d9:dd:c25:c25:94de:6451
832c19:dd:d9:dd:c25:c25:94de:6452/1282c19:dd:d9:dd:c25:c25:94de:6452
842c19:dd:d9:dd:c25:c25:94de:6453/1282c19:dd:d9:dd:c25:c25:94de:6453
852c19:dd:d9:dd:c25:c25:94de:6454/1282c19:dd:d9:dd:c25:c25:94de:6454
862c19:dd:d9:dd:c25:c25:94de:6455/1282c19:dd:d9:dd:c25:c25:94de:6455
872c19:dd:d9:dd:c25:c25:94de:6456/1282c19:dd:d9:dd:c25:c25:94de:6456
882c19:dd:d9:dd:c25:c25:94de:6457/1282c19:dd:d9:dd:c25:c25:94de:6457
892c19:dd:d9:dd:c25:c25:94de:6458/1282c19:dd:d9:dd:c25:c25:94de:6458
902c19:dd:d9:dd:c25:c25:94de:6459/1282c19:dd:d9:dd:c25:c25:94de:6459
912c19:dd:d9:dd:c25:c25:94de:645a/1282c19:dd:d9:dd:c25:c25:94de:645a
922c19:dd:d9:dd:c25:c25:94de:645b/1282c19:dd:d9:dd:c25:c25:94de:645b
932c19:dd:d9:dd:c25:c25:94de:645c/1282c19:dd:d9:dd:c25:c25:94de:645c
942c19:dd:d9:dd:c25:c25:94de:645d/1282c19:dd:d9:dd:c25:c25:94de:645d
952c19:dd:d9:dd:c25:c25:94de:645e/1282c19:dd:d9:dd:c25:c25:94de:645e
962c19:dd:d9:dd:c25:c25:94de:645f/1282c19:dd:d9:dd:c25:c25:94de:645f
972c19:dd:d9:dd:c25:c25:94de:6460/1282c19:dd:d9:dd:c25:c25:94de:6460
982c19:dd:d9:dd:c25:c25:94de:6461/1282c19:dd:d9:dd:c25:c25:94de:6461
992c19:dd:d9:dd:c25:c25:94de:6462/1282c19:dd:d9:dd:c25:c25:94de:6462
1002c19:dd:d9:dd:c25:c25:94de:6463/1282c19:dd:d9:dd:c25:c25:94de:6463
1012c19:dd:d9:dd:c25:c25:94de:6464/1282c19:dd:d9:dd:c25:c25:94de:6464
1022c19:dd:d9:dd:c25:c25:94de:6465/1282c19:dd:d9:dd:c25:c25:94de:6465
1032c19:dd:d9:dd:c25:c25:94de:6466/1282c19:dd:d9:dd:c25:c25:94de:6466
1042c19:dd:d9:dd:c25:c25:94de:6467/1282c19:dd:d9:dd:c25:c25:94de:6467
1052c19:dd:d9:dd:c25:c25:94de:6468/1282c19:dd:d9:dd:c25:c25:94de:6468
1062c19:dd:d9:dd:c25:c25:94de:6469/1282c19:dd:d9:dd:c25:c25:94de:6469
1072c19:dd:d9:dd:c25:c25:94de:646a/1282c19:dd:d9:dd:c25:c25:94de:646a
1082c19:dd:d9:dd:c25:c25:94de:646b/1282c19:dd:d9:dd:c25:c25:94de:646b
1092c19:dd:d9:dd:c25:c25:94de:646c/1282c19:dd:d9:dd:c25:c25:94de:646c
1102c19:dd:d9:dd:c25:c25:94de:646d/1282c19:dd:d9:dd:c25:c25:94de:646d
1112c19:dd:d9:dd:c25:c25:94de:646e/1282c19:dd:d9:dd:c25:c25:94de:646e
1122c19:dd:d9:dd:c25:c25:94de:646f/1282c19:dd:d9:dd:c25:c25:94de:646f
1132c19:dd:d9:dd:c25:c25:94de:6470/1282c19:dd:d9:dd:c25:c25:94de:6470
1142c19:dd:d9:dd:c25:c25:94de:6471/1282c19:dd:d9:dd:c25:c25:94de:6471
1152c19:dd:d9:dd:c25:c25:94de:6472/1282c19:dd:d9:dd:c25:c25:94de:6472
1162c19:dd:d9:dd:c25:c25:94de:6473/1282c19:dd:d9:dd:c25:c25:94de:6473
1172c19:dd:d9:dd:c25:c25:94de:6474/1282c19:dd:d9:dd:c25:c25:94de:6474
1182c19:dd:d9:dd:c25:c25:94de:6475/1282c19:dd:d9:dd:c25:c25:94de:6475
1192c19:dd:d9:dd:c25:c25:94de:6476/1282c19:dd:d9:dd:c25:c25:94de:6476
1202c19:dd:d9:dd:c25:c25:94de:6477/1282c19:dd:d9:dd:c25:c25:94de:6477
1212c19:dd:d9:dd:c25:c25:94de:6478/1282c19:dd:d9:dd:c25:c25:94de:6478
1222c19:dd:d9:dd:c25:c25:94de:6479/1282c19:dd:d9:dd:c25:c25:94de:6479
1232c19:dd:d9:dd:c25:c25:94de:647a/1282c19:dd:d9:dd:c25:c25:94de:647a
1242c19:dd:d9:dd:c25:c25:94de:647b/1282c19:dd:d9:dd:c25:c25:94de:647b
1252c19:dd:d9:dd:c25:c25:94de:647c/1282c19:dd:d9:dd:c25:c25:94de:647c
1262c19:dd:d9:dd:c25:c25:94de:647d/1282c19:dd:d9:dd:c25:c25:94de:647d
1272c19:dd:d9:dd:c25:c25:94de:647e/1282c19:dd:d9:dd:c25:c25:94de:647e
1282c19:dd:d9:dd:c25:c25:94de:647f/1282c19:dd:d9:dd:c25:c25:94de:647f
1292c19:dd:d9:dd:c25:c25:94de:6480/1282c19:dd:d9:dd:c25:c25:94de:6480
1302c19:dd:d9:dd:c25:c25:94de:6481/1282c19:dd:d9:dd:c25:c25:94de:6481
1312c19:dd:d9:dd:c25:c25:94de:6482/1282c19:dd:d9:dd:c25:c25:94de:6482
1322c19:dd:d9:dd:c25:c25:94de:6483/1282c19:dd:d9:dd:c25:c25:94de:6483
1332c19:dd:d9:dd:c25:c25:94de:6484/1282c19:dd:d9:dd:c25:c25:94de:6484
1342c19:dd:d9:dd:c25:c25:94de:6485/1282c19:dd:d9:dd:c25:c25:94de:6485
1352c19:dd:d9:dd:c25:c25:94de:6486/1282c19:dd:d9:dd:c25:c25:94de:6486
1362c19:dd:d9:dd:c25:c25:94de:6487/1282c19:dd:d9:dd:c25:c25:94de:6487
1372c19:dd:d9:dd:c25:c25:94de:6488/1282c19:dd:d9:dd:c25:c25:94de:6488
1382c19:dd:d9:dd:c25:c25:94de:6489/1282c19:dd:d9:dd:c25:c25:94de:6489
1392c19:dd:d9:dd:c25:c25:94de:648a/1282c19:dd:d9:dd:c25:c25:94de:648a
1402c19:dd:d9:dd:c25:c25:94de:648b/1282c19:dd:d9:dd:c25:c25:94de:648b
1412c19:dd:d9:dd:c25:c25:94de:648c/1282c19:dd:d9:dd:c25:c25:94de:648c
1422c19:dd:d9:dd:c25:c25:94de:648d/1282c19:dd:d9:dd:c25:c25:94de:648d
1432c19:dd:d9:dd:c25:c25:94de:648e/1282c19:dd:d9:dd:c25:c25:94de:648e
1442c19:dd:d9:dd:c25:c25:94de:648f/1282c19:dd:d9:dd:c25:c25:94de:648f
1452c19:dd:d9:dd:c25:c25:94de:6490/1282c19:dd:d9:dd:c25:c25:94de:6490
1462c19:dd:d9:dd:c25:c25:94de:6491/1282c19:dd:d9:dd:c25:c25:94de:6491
1472c19:dd:d9:dd:c25:c25:94de:6492/1282c19:dd:d9:dd:c25:c25:94de:6492
1482c19:dd:d9:dd:c25:c25:94de:6493/1282c19:dd:d9:dd:c25:c25:94de:6493
1492c19:dd:d9:dd:c25:c25:94de:6494/1282c19:dd:d9:dd:c25:c25:94de:6494
1502c19:dd:d9:dd:c25:c25:94de:6495/1282c19:dd:d9:dd:c25:c25:94de:6495
1512c19:dd:d9:dd:c25:c25:94de:6496/1282c19:dd:d9:dd:c25:c25:94de:6496
1522c19:dd:d9:dd:c25:c25:94de:6497/1282c19:dd:d9:dd:c25:c25:94de:6497
1532c19:dd:d9:dd:c25:c25:94de:6498/1282c19:dd:d9:dd:c25:c25:94de:6498
1542c19:dd:d9:dd:c25:c25:94de:6499/1282c19:dd:d9:dd:c25:c25:94de:6499
1552c19:dd:d9:dd:c25:c25:94de:649a/1282c19:dd:d9:dd:c25:c25:94de:649a
1562c19:dd:d9:dd:c25:c25:94de:649b/1282c19:dd:d9:dd:c25:c25:94de:649b
1572c19:dd:d9:dd:c25:c25:94de:649c/1282c19:dd:d9:dd:c25:c25:94de:649c
1582c19:dd:d9:dd:c25:c25:94de:649d/1282c19:dd:d9:dd:c25:c25:94de:649d
1592c19:dd:d9:dd:c25:c25:94de:649e/1282c19:dd:d9:dd:c25:c25:94de:649e
1602c19:dd:d9:dd:c25:c25:94de:649f/1282c19:dd:d9:dd:c25:c25:94de:649f
1612c19:dd:d9:dd:c25:c25:94de:64a0/1282c19:dd:d9:dd:c25:c25:94de:64a0
1622c19:dd:d9:dd:c25:c25:94de:64a1/1282c19:dd:d9:dd:c25:c25:94de:64a1
1632c19:dd:d9:dd:c25:c25:94de:64a2/1282c19:dd:d9:dd:c25:c25:94de:64a2
1642c19:dd:d9:dd:c25:c25:94de:64a3/1282c19:dd:d9:dd:c25:c25:94de:64a3
1652c19:dd:d9:dd:c25:c25:94de:64a4/1282c19:dd:d9:dd:c25:c25:94de:64a4
1662c19:dd:d9:dd:c25:c25:94de:64a5/1282c19:dd:d9:dd:c25:c25:94de:64a5
1672c19:dd:d9:dd:c25:c25:94de:64a6/1282c19:dd:d9:dd:c25:c25:94de:64a6
1682c19:dd:d9:dd:c25:c25:94de:64a7/1282c19:dd:d9:dd:c25:c25:94de:64a7
1692c19:dd:d9:dd:c25:c25:94de:64a8/1282c19:dd:d9:dd:c25:c25:94de:64a8
1702c19:dd:d9:dd:c25:c25:94de:64a9/1282c19:dd:d9:dd:c25:c25:94de:64a9
1712c19:dd:d9:dd:c25:c25:94de:64aa/1282c19:dd:d9:dd:c25:c25:94de:64aa
1722c19:dd:d9:dd:c25:c25:94de:64ab/1282c19:dd:d9:dd:c25:c25:94de:64ab
1732c19:dd:d9:dd:c25:c25:94de:64ac/1282c19:dd:d9:dd:c25:c25:94de:64ac
1742c19:dd:d9:dd:c25:c25:94de:64ad/1282c19:dd:d9:dd:c25:c25:94de:64ad
1752c19:dd:d9:dd:c25:c25:94de:64ae/1282c19:dd:d9:dd:c25:c25:94de:64ae
1762c19:dd:d9:dd:c25:c25:94de:64af/1282c19:dd:d9:dd:c25:c25:94de:64af
1772c19:dd:d9:dd:c25:c25:94de:64b0/1282c19:dd:d9:dd:c25:c25:94de:64b0
1782c19:dd:d9:dd:c25:c25:94de:64b1/1282c19:dd:d9:dd:c25:c25:94de:64b1
1792c19:dd:d9:dd:c25:c25:94de:64b2/1282c19:dd:d9:dd:c25:c25:94de:64b2
1802c19:dd:d9:dd:c25:c25:94de:64b3/1282c19:dd:d9:dd:c25:c25:94de:64b3
1812c19:dd:d9:dd:c25:c25:94de:64b4/1282c19:dd:d9:dd:c25:c25:94de:64b4
1822c19:dd:d9:dd:c25:c25:94de:64b5/1282c19:dd:d9:dd:c25:c25:94de:64b5
1832c19:dd:d9:dd:c25:c25:94de:64b6/1282c19:dd:d9:dd:c25:c25:94de:64b6
1842c19:dd:d9:dd:c25:c25:94de:64b7/1282c19:dd:d9:dd:c25:c25:94de:64b7
1852c19:dd:d9:dd:c25:c25:94de:64b8/1282c19:dd:d9:dd:c25:c25:94de:64b8
1862c19:dd:d9:dd:c25:c25:94de:64b9/1282c19:dd:d9:dd:c25:c25:94de:64b9
1872c19:dd:d9:dd:c25:c25:94de:64ba/1282c19:dd:d9:dd:c25:c25:94de:64ba
1882c19:dd:d9:dd:c25:c25:94de:64bb/1282c19:dd:d9:dd:c25:c25:94de:64bb
1892c19:dd:d9:dd:c25:c25:94de:64bc/1282c19:dd:d9:dd:c25:c25:94de:64bc
1902c19:dd:d9:dd:c25:c25:94de:64bd/1282c19:dd:d9:dd:c25:c25:94de:64bd
1912c19:dd:d9:dd:c25:c25:94de:64be/1282c19:dd:d9:dd:c25:c25:94de:64be
1922c19:dd:d9:dd:c25:c25:94de:64bf/1282c19:dd:d9:dd:c25:c25:94de:64bf
1932c19:dd:d9:dd:c25:c25:94de:64c0/1282c19:dd:d9:dd:c25:c25:94de:64c0
1942c19:dd:d9:dd:c25:c25:94de:64c1/1282c19:dd:d9:dd:c25:c25:94de:64c1
1952c19:dd:d9:dd:c25:c25:94de:64c2/1282c19:dd:d9:dd:c25:c25:94de:64c2
1962c19:dd:d9:dd:c25:c25:94de:64c3/1282c19:dd:d9:dd:c25:c25:94de:64c3
1972c19:dd:d9:dd:c25:c25:94de:64c4/1282c19:dd:d9:dd:c25:c25:94de:64c4
1982c19:dd:d9:dd:c25:c25:94de:64c5/1282c19:dd:d9:dd:c25:c25:94de:64c5
1992c19:dd:d9:dd:c25:c25:94de:64c6/1282c19:dd:d9:dd:c25:c25:94de:64c6
2002c19:dd:d9:dd:c25:c25:94de:64c7/1282c19:dd:d9:dd:c25:c25:94de:64c7
2012c19:dd:d9:dd:c25:c25:94de:64c8/1282c19:dd:d9:dd:c25:c25:94de:64c8
2022c19:dd:d9:dd:c25:c25:94de:64c9/1282c19:dd:d9:dd:c25:c25:94de:64c9
2032c19:dd:d9:dd:c25:c25:94de:64ca/1282c19:dd:d9:dd:c25:c25:94de:64ca
2042c19:dd:d9:dd:c25:c25:94de:64cb/1282c19:dd:d9:dd:c25:c25:94de:64cb
2052c19:dd:d9:dd:c25:c25:94de:64cc/1282c19:dd:d9:dd:c25:c25:94de:64cc
2062c19:dd:d9:dd:c25:c25:94de:64cd/1282c19:dd:d9:dd:c25:c25:94de:64cd
2072c19:dd:d9:dd:c25:c25:94de:64ce/1282c19:dd:d9:dd:c25:c25:94de:64ce
2082c19:dd:d9:dd:c25:c25:94de:64cf/1282c19:dd:d9:dd:c25:c25:94de:64cf
2092c19:dd:d9:dd:c25:c25:94de:64d0/1282c19:dd:d9:dd:c25:c25:94de:64d0
2102c19:dd:d9:dd:c25:c25:94de:64d1/1282c19:dd:d9:dd:c25:c25:94de:64d1
2112c19:dd:d9:dd:c25:c25:94de:64d2/1282c19:dd:d9:dd:c25:c25:94de:64d2
2122c19:dd:d9:dd:c25:c25:94de:64d3/1282c19:dd:d9:dd:c25:c25:94de:64d3
2132c19:dd:d9:dd:c25:c25:94de:64d4/1282c19:dd:d9:dd:c25:c25:94de:64d4
2142c19:dd:d9:dd:c25:c25:94de:64d5/1282c19:dd:d9:dd:c25:c25:94de:64d5
2152c19:dd:d9:dd:c25:c25:94de:64d6/1282c19:dd:d9:dd:c25:c25:94de:64d6
2162c19:dd:d9:dd:c25:c25:94de:64d7/1282c19:dd:d9:dd:c25:c25:94de:64d7
2172c19:dd:d9:dd:c25:c25:94de:64d8/1282c19:dd:d9:dd:c25:c25:94de:64d8
2182c19:dd:d9:dd:c25:c25:94de:64d9/1282c19:dd:d9:dd:c25:c25:94de:64d9
2192c19:dd:d9:dd:c25:c25:94de:64da/1282c19:dd:d9:dd:c25:c25:94de:64da
2202c19:dd:d9:dd:c25:c25:94de:64db/1282c19:dd:d9:dd:c25:c25:94de:64db
2212c19:dd:d9:dd:c25:c25:94de:64dc/1282c19:dd:d9:dd:c25:c25:94de:64dc
2222c19:dd:d9:dd:c25:c25:94de:64dd/1282c19:dd:d9:dd:c25:c25:94de:64dd
2232c19:dd:d9:dd:c25:c25:94de:64de/1282c19:dd:d9:dd:c25:c25:94de:64de
2242c19:dd:d9:dd:c25:c25:94de:64df/1282c19:dd:d9:dd:c25:c25:94de:64df
2252c19:dd:d9:dd:c25:c25:94de:64e0/1282c19:dd:d9:dd:c25:c25:94de:64e0
2262c19:dd:d9:dd:c25:c25:94de:64e1/1282c19:dd:d9:dd:c25:c25:94de:64e1
2272c19:dd:d9:dd:c25:c25:94de:64e2/1282c19:dd:d9:dd:c25:c25:94de:64e2
2282c19:dd:d9:dd:c25:c25:94de:64e3/1282c19:dd:d9:dd:c25:c25:94de:64e3
2292c19:dd:d9:dd:c25:c25:94de:64e4/1282c19:dd:d9:dd:c25:c25:94de:64e4
2302c19:dd:d9:dd:c25:c25:94de:64e5/1282c19:dd:d9:dd:c25:c25:94de:64e5
2312c19:dd:d9:dd:c25:c25:94de:64e6/1282c19:dd:d9:dd:c25:c25:94de:64e6
2322c19:dd:d9:dd:c25:c25:94de:64e7/1282c19:dd:d9:dd:c25:c25:94de:64e7
2332c19:dd:d9:dd:c25:c25:94de:64e8/1282c19:dd:d9:dd:c25:c25:94de:64e8
2342c19:dd:d9:dd:c25:c25:94de:64e9/1282c19:dd:d9:dd:c25:c25:94de:64e9
2352c19:dd:d9:dd:c25:c25:94de:64ea/1282c19:dd:d9:dd:c25:c25:94de:64ea
2362c19:dd:d9:dd:c25:c25:94de:64eb/1282c19:dd:d9:dd:c25:c25:94de:64eb
2372c19:dd:d9:dd:c25:c25:94de:64ec/1282c19:dd:d9:dd:c25:c25:94de:64ec
2382c19:dd:d9:dd:c25:c25:94de:64ed/1282c19:dd:d9:dd:c25:c25:94de:64ed
2392c19:dd:d9:dd:c25:c25:94de:64ee/1282c19:dd:d9:dd:c25:c25:94de:64ee
2402c19:dd:d9:dd:c25:c25:94de:64ef/1282c19:dd:d9:dd:c25:c25:94de:64ef
2412c19:dd:d9:dd:c25:c25:94de:64f0/1282c19:dd:d9:dd:c25:c25:94de:64f0
2422c19:dd:d9:dd:c25:c25:94de:64f1/1282c19:dd:d9:dd:c25:c25:94de:64f1
2432c19:dd:d9:dd:c25:c25:94de:64f2/1282c19:dd:d9:dd:c25:c25:94de:64f2
2442c19:dd:d9:dd:c25:c25:94de:64f3/1282c19:dd:d9:dd:c25:c25:94de:64f3
2452c19:dd:d9:dd:c25:c25:94de:64f4/1282c19:dd:d9:dd:c25:c25:94de:64f4
2462c19:dd:d9:dd:c25:c25:94de:64f5/1282c19:dd:d9:dd:c25:c25:94de:64f5
2472c19:dd:d9:dd:c25:c25:94de:64f6/1282c19:dd:d9:dd:c25:c25:94de:64f6
2482c19:dd:d9:dd:c25:c25:94de:64f7/1282c19:dd:d9:dd:c25:c25:94de:64f7
2492c19:dd:d9:dd:c25:c25:94de:64f8/1282c19:dd:d9:dd:c25:c25:94de:64f8
2502c19:dd:d9:dd:c25:c25:94de:64f9/1282c19:dd:d9:dd:c25:c25:94de:64f9
2512c19:dd:d9:dd:c25:c25:94de:64fa/1282c19:dd:d9:dd:c25:c25:94de:64fa
2522c19:dd:d9:dd:c25:c25:94de:64fb/1282c19:dd:d9:dd:c25:c25:94de:64fb
2532c19:dd:d9:dd:c25:c25:94de:64fc/1282c19:dd:d9:dd:c25:c25:94de:64fc
2542c19:dd:d9:dd:c25:c25:94de:64fd/1282c19:dd:d9:dd:c25:c25:94de:64fd
2552c19:dd:d9:dd:c25:c25:94de:64fe/1282c19:dd:d9:dd:c25:c25:94de:64fe
2562c19:dd:d9:dd:c25:c25:94de:64ff/1282c19:dd:d9:dd:c25:c25:94de:64ff

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.