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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:c25b:d00a:9400/120
First address
2c19:dd:d9:dd:c25:c25b:d00a:9400
Last address
2c19:dd:d9:dd:c25:c25b:d00a:94ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:c25b:d00a:9400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
4.9.a.0.0.d.b.5.2.c.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:c25b:d00a:9400/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25b:d00a:9400/1282c19:dd:d9:dd:c25:c25b:d00a:9400
22c19:dd:d9:dd:c25:c25b:d00a:9401/1282c19:dd:d9:dd:c25:c25b:d00a:9401
32c19:dd:d9:dd:c25:c25b:d00a:9402/1282c19:dd:d9:dd:c25:c25b:d00a:9402
42c19:dd:d9:dd:c25:c25b:d00a:9403/1282c19:dd:d9:dd:c25:c25b:d00a:9403
52c19:dd:d9:dd:c25:c25b:d00a:9404/1282c19:dd:d9:dd:c25:c25b:d00a:9404
62c19:dd:d9:dd:c25:c25b:d00a:9405/1282c19:dd:d9:dd:c25:c25b:d00a:9405
72c19:dd:d9:dd:c25:c25b:d00a:9406/1282c19:dd:d9:dd:c25:c25b:d00a:9406
82c19:dd:d9:dd:c25:c25b:d00a:9407/1282c19:dd:d9:dd:c25:c25b:d00a:9407
92c19:dd:d9:dd:c25:c25b:d00a:9408/1282c19:dd:d9:dd:c25:c25b:d00a:9408
102c19:dd:d9:dd:c25:c25b:d00a:9409/1282c19:dd:d9:dd:c25:c25b:d00a:9409
112c19:dd:d9:dd:c25:c25b:d00a:940a/1282c19:dd:d9:dd:c25:c25b:d00a:940a
122c19:dd:d9:dd:c25:c25b:d00a:940b/1282c19:dd:d9:dd:c25:c25b:d00a:940b
132c19:dd:d9:dd:c25:c25b:d00a:940c/1282c19:dd:d9:dd:c25:c25b:d00a:940c
142c19:dd:d9:dd:c25:c25b:d00a:940d/1282c19:dd:d9:dd:c25:c25b:d00a:940d
152c19:dd:d9:dd:c25:c25b:d00a:940e/1282c19:dd:d9:dd:c25:c25b:d00a:940e
162c19:dd:d9:dd:c25:c25b:d00a:940f/1282c19:dd:d9:dd:c25:c25b:d00a:940f
172c19:dd:d9:dd:c25:c25b:d00a:9410/1282c19:dd:d9:dd:c25:c25b:d00a:9410
182c19:dd:d9:dd:c25:c25b:d00a:9411/1282c19:dd:d9:dd:c25:c25b:d00a:9411
192c19:dd:d9:dd:c25:c25b:d00a:9412/1282c19:dd:d9:dd:c25:c25b:d00a:9412
202c19:dd:d9:dd:c25:c25b:d00a:9413/1282c19:dd:d9:dd:c25:c25b:d00a:9413
212c19:dd:d9:dd:c25:c25b:d00a:9414/1282c19:dd:d9:dd:c25:c25b:d00a:9414
222c19:dd:d9:dd:c25:c25b:d00a:9415/1282c19:dd:d9:dd:c25:c25b:d00a:9415
232c19:dd:d9:dd:c25:c25b:d00a:9416/1282c19:dd:d9:dd:c25:c25b:d00a:9416
242c19:dd:d9:dd:c25:c25b:d00a:9417/1282c19:dd:d9:dd:c25:c25b:d00a:9417
252c19:dd:d9:dd:c25:c25b:d00a:9418/1282c19:dd:d9:dd:c25:c25b:d00a:9418
262c19:dd:d9:dd:c25:c25b:d00a:9419/1282c19:dd:d9:dd:c25:c25b:d00a:9419
272c19:dd:d9:dd:c25:c25b:d00a:941a/1282c19:dd:d9:dd:c25:c25b:d00a:941a
282c19:dd:d9:dd:c25:c25b:d00a:941b/1282c19:dd:d9:dd:c25:c25b:d00a:941b
292c19:dd:d9:dd:c25:c25b:d00a:941c/1282c19:dd:d9:dd:c25:c25b:d00a:941c
302c19:dd:d9:dd:c25:c25b:d00a:941d/1282c19:dd:d9:dd:c25:c25b:d00a:941d
312c19:dd:d9:dd:c25:c25b:d00a:941e/1282c19:dd:d9:dd:c25:c25b:d00a:941e
322c19:dd:d9:dd:c25:c25b:d00a:941f/1282c19:dd:d9:dd:c25:c25b:d00a:941f
332c19:dd:d9:dd:c25:c25b:d00a:9420/1282c19:dd:d9:dd:c25:c25b:d00a:9420
342c19:dd:d9:dd:c25:c25b:d00a:9421/1282c19:dd:d9:dd:c25:c25b:d00a:9421
352c19:dd:d9:dd:c25:c25b:d00a:9422/1282c19:dd:d9:dd:c25:c25b:d00a:9422
362c19:dd:d9:dd:c25:c25b:d00a:9423/1282c19:dd:d9:dd:c25:c25b:d00a:9423
372c19:dd:d9:dd:c25:c25b:d00a:9424/1282c19:dd:d9:dd:c25:c25b:d00a:9424
382c19:dd:d9:dd:c25:c25b:d00a:9425/1282c19:dd:d9:dd:c25:c25b:d00a:9425
392c19:dd:d9:dd:c25:c25b:d00a:9426/1282c19:dd:d9:dd:c25:c25b:d00a:9426
402c19:dd:d9:dd:c25:c25b:d00a:9427/1282c19:dd:d9:dd:c25:c25b:d00a:9427
412c19:dd:d9:dd:c25:c25b:d00a:9428/1282c19:dd:d9:dd:c25:c25b:d00a:9428
422c19:dd:d9:dd:c25:c25b:d00a:9429/1282c19:dd:d9:dd:c25:c25b:d00a:9429
432c19:dd:d9:dd:c25:c25b:d00a:942a/1282c19:dd:d9:dd:c25:c25b:d00a:942a
442c19:dd:d9:dd:c25:c25b:d00a:942b/1282c19:dd:d9:dd:c25:c25b:d00a:942b
452c19:dd:d9:dd:c25:c25b:d00a:942c/1282c19:dd:d9:dd:c25:c25b:d00a:942c
462c19:dd:d9:dd:c25:c25b:d00a:942d/1282c19:dd:d9:dd:c25:c25b:d00a:942d
472c19:dd:d9:dd:c25:c25b:d00a:942e/1282c19:dd:d9:dd:c25:c25b:d00a:942e
482c19:dd:d9:dd:c25:c25b:d00a:942f/1282c19:dd:d9:dd:c25:c25b:d00a:942f
492c19:dd:d9:dd:c25:c25b:d00a:9430/1282c19:dd:d9:dd:c25:c25b:d00a:9430
502c19:dd:d9:dd:c25:c25b:d00a:9431/1282c19:dd:d9:dd:c25:c25b:d00a:9431
512c19:dd:d9:dd:c25:c25b:d00a:9432/1282c19:dd:d9:dd:c25:c25b:d00a:9432
522c19:dd:d9:dd:c25:c25b:d00a:9433/1282c19:dd:d9:dd:c25:c25b:d00a:9433
532c19:dd:d9:dd:c25:c25b:d00a:9434/1282c19:dd:d9:dd:c25:c25b:d00a:9434
542c19:dd:d9:dd:c25:c25b:d00a:9435/1282c19:dd:d9:dd:c25:c25b:d00a:9435
552c19:dd:d9:dd:c25:c25b:d00a:9436/1282c19:dd:d9:dd:c25:c25b:d00a:9436
562c19:dd:d9:dd:c25:c25b:d00a:9437/1282c19:dd:d9:dd:c25:c25b:d00a:9437
572c19:dd:d9:dd:c25:c25b:d00a:9438/1282c19:dd:d9:dd:c25:c25b:d00a:9438
582c19:dd:d9:dd:c25:c25b:d00a:9439/1282c19:dd:d9:dd:c25:c25b:d00a:9439
592c19:dd:d9:dd:c25:c25b:d00a:943a/1282c19:dd:d9:dd:c25:c25b:d00a:943a
602c19:dd:d9:dd:c25:c25b:d00a:943b/1282c19:dd:d9:dd:c25:c25b:d00a:943b
612c19:dd:d9:dd:c25:c25b:d00a:943c/1282c19:dd:d9:dd:c25:c25b:d00a:943c
622c19:dd:d9:dd:c25:c25b:d00a:943d/1282c19:dd:d9:dd:c25:c25b:d00a:943d
632c19:dd:d9:dd:c25:c25b:d00a:943e/1282c19:dd:d9:dd:c25:c25b:d00a:943e
642c19:dd:d9:dd:c25:c25b:d00a:943f/1282c19:dd:d9:dd:c25:c25b:d00a:943f
652c19:dd:d9:dd:c25:c25b:d00a:9440/1282c19:dd:d9:dd:c25:c25b:d00a:9440
662c19:dd:d9:dd:c25:c25b:d00a:9441/1282c19:dd:d9:dd:c25:c25b:d00a:9441
672c19:dd:d9:dd:c25:c25b:d00a:9442/1282c19:dd:d9:dd:c25:c25b:d00a:9442
682c19:dd:d9:dd:c25:c25b:d00a:9443/1282c19:dd:d9:dd:c25:c25b:d00a:9443
692c19:dd:d9:dd:c25:c25b:d00a:9444/1282c19:dd:d9:dd:c25:c25b:d00a:9444
702c19:dd:d9:dd:c25:c25b:d00a:9445/1282c19:dd:d9:dd:c25:c25b:d00a:9445
712c19:dd:d9:dd:c25:c25b:d00a:9446/1282c19:dd:d9:dd:c25:c25b:d00a:9446
722c19:dd:d9:dd:c25:c25b:d00a:9447/1282c19:dd:d9:dd:c25:c25b:d00a:9447
732c19:dd:d9:dd:c25:c25b:d00a:9448/1282c19:dd:d9:dd:c25:c25b:d00a:9448
742c19:dd:d9:dd:c25:c25b:d00a:9449/1282c19:dd:d9:dd:c25:c25b:d00a:9449
752c19:dd:d9:dd:c25:c25b:d00a:944a/1282c19:dd:d9:dd:c25:c25b:d00a:944a
762c19:dd:d9:dd:c25:c25b:d00a:944b/1282c19:dd:d9:dd:c25:c25b:d00a:944b
772c19:dd:d9:dd:c25:c25b:d00a:944c/1282c19:dd:d9:dd:c25:c25b:d00a:944c
782c19:dd:d9:dd:c25:c25b:d00a:944d/1282c19:dd:d9:dd:c25:c25b:d00a:944d
792c19:dd:d9:dd:c25:c25b:d00a:944e/1282c19:dd:d9:dd:c25:c25b:d00a:944e
802c19:dd:d9:dd:c25:c25b:d00a:944f/1282c19:dd:d9:dd:c25:c25b:d00a:944f
812c19:dd:d9:dd:c25:c25b:d00a:9450/1282c19:dd:d9:dd:c25:c25b:d00a:9450
822c19:dd:d9:dd:c25:c25b:d00a:9451/1282c19:dd:d9:dd:c25:c25b:d00a:9451
832c19:dd:d9:dd:c25:c25b:d00a:9452/1282c19:dd:d9:dd:c25:c25b:d00a:9452
842c19:dd:d9:dd:c25:c25b:d00a:9453/1282c19:dd:d9:dd:c25:c25b:d00a:9453
852c19:dd:d9:dd:c25:c25b:d00a:9454/1282c19:dd:d9:dd:c25:c25b:d00a:9454
862c19:dd:d9:dd:c25:c25b:d00a:9455/1282c19:dd:d9:dd:c25:c25b:d00a:9455
872c19:dd:d9:dd:c25:c25b:d00a:9456/1282c19:dd:d9:dd:c25:c25b:d00a:9456
882c19:dd:d9:dd:c25:c25b:d00a:9457/1282c19:dd:d9:dd:c25:c25b:d00a:9457
892c19:dd:d9:dd:c25:c25b:d00a:9458/1282c19:dd:d9:dd:c25:c25b:d00a:9458
902c19:dd:d9:dd:c25:c25b:d00a:9459/1282c19:dd:d9:dd:c25:c25b:d00a:9459
912c19:dd:d9:dd:c25:c25b:d00a:945a/1282c19:dd:d9:dd:c25:c25b:d00a:945a
922c19:dd:d9:dd:c25:c25b:d00a:945b/1282c19:dd:d9:dd:c25:c25b:d00a:945b
932c19:dd:d9:dd:c25:c25b:d00a:945c/1282c19:dd:d9:dd:c25:c25b:d00a:945c
942c19:dd:d9:dd:c25:c25b:d00a:945d/1282c19:dd:d9:dd:c25:c25b:d00a:945d
952c19:dd:d9:dd:c25:c25b:d00a:945e/1282c19:dd:d9:dd:c25:c25b:d00a:945e
962c19:dd:d9:dd:c25:c25b:d00a:945f/1282c19:dd:d9:dd:c25:c25b:d00a:945f
972c19:dd:d9:dd:c25:c25b:d00a:9460/1282c19:dd:d9:dd:c25:c25b:d00a:9460
982c19:dd:d9:dd:c25:c25b:d00a:9461/1282c19:dd:d9:dd:c25:c25b:d00a:9461
992c19:dd:d9:dd:c25:c25b:d00a:9462/1282c19:dd:d9:dd:c25:c25b:d00a:9462
1002c19:dd:d9:dd:c25:c25b:d00a:9463/1282c19:dd:d9:dd:c25:c25b:d00a:9463
1012c19:dd:d9:dd:c25:c25b:d00a:9464/1282c19:dd:d9:dd:c25:c25b:d00a:9464
1022c19:dd:d9:dd:c25:c25b:d00a:9465/1282c19:dd:d9:dd:c25:c25b:d00a:9465
1032c19:dd:d9:dd:c25:c25b:d00a:9466/1282c19:dd:d9:dd:c25:c25b:d00a:9466
1042c19:dd:d9:dd:c25:c25b:d00a:9467/1282c19:dd:d9:dd:c25:c25b:d00a:9467
1052c19:dd:d9:dd:c25:c25b:d00a:9468/1282c19:dd:d9:dd:c25:c25b:d00a:9468
1062c19:dd:d9:dd:c25:c25b:d00a:9469/1282c19:dd:d9:dd:c25:c25b:d00a:9469
1072c19:dd:d9:dd:c25:c25b:d00a:946a/1282c19:dd:d9:dd:c25:c25b:d00a:946a
1082c19:dd:d9:dd:c25:c25b:d00a:946b/1282c19:dd:d9:dd:c25:c25b:d00a:946b
1092c19:dd:d9:dd:c25:c25b:d00a:946c/1282c19:dd:d9:dd:c25:c25b:d00a:946c
1102c19:dd:d9:dd:c25:c25b:d00a:946d/1282c19:dd:d9:dd:c25:c25b:d00a:946d
1112c19:dd:d9:dd:c25:c25b:d00a:946e/1282c19:dd:d9:dd:c25:c25b:d00a:946e
1122c19:dd:d9:dd:c25:c25b:d00a:946f/1282c19:dd:d9:dd:c25:c25b:d00a:946f
1132c19:dd:d9:dd:c25:c25b:d00a:9470/1282c19:dd:d9:dd:c25:c25b:d00a:9470
1142c19:dd:d9:dd:c25:c25b:d00a:9471/1282c19:dd:d9:dd:c25:c25b:d00a:9471
1152c19:dd:d9:dd:c25:c25b:d00a:9472/1282c19:dd:d9:dd:c25:c25b:d00a:9472
1162c19:dd:d9:dd:c25:c25b:d00a:9473/1282c19:dd:d9:dd:c25:c25b:d00a:9473
1172c19:dd:d9:dd:c25:c25b:d00a:9474/1282c19:dd:d9:dd:c25:c25b:d00a:9474
1182c19:dd:d9:dd:c25:c25b:d00a:9475/1282c19:dd:d9:dd:c25:c25b:d00a:9475
1192c19:dd:d9:dd:c25:c25b:d00a:9476/1282c19:dd:d9:dd:c25:c25b:d00a:9476
1202c19:dd:d9:dd:c25:c25b:d00a:9477/1282c19:dd:d9:dd:c25:c25b:d00a:9477
1212c19:dd:d9:dd:c25:c25b:d00a:9478/1282c19:dd:d9:dd:c25:c25b:d00a:9478
1222c19:dd:d9:dd:c25:c25b:d00a:9479/1282c19:dd:d9:dd:c25:c25b:d00a:9479
1232c19:dd:d9:dd:c25:c25b:d00a:947a/1282c19:dd:d9:dd:c25:c25b:d00a:947a
1242c19:dd:d9:dd:c25:c25b:d00a:947b/1282c19:dd:d9:dd:c25:c25b:d00a:947b
1252c19:dd:d9:dd:c25:c25b:d00a:947c/1282c19:dd:d9:dd:c25:c25b:d00a:947c
1262c19:dd:d9:dd:c25:c25b:d00a:947d/1282c19:dd:d9:dd:c25:c25b:d00a:947d
1272c19:dd:d9:dd:c25:c25b:d00a:947e/1282c19:dd:d9:dd:c25:c25b:d00a:947e
1282c19:dd:d9:dd:c25:c25b:d00a:947f/1282c19:dd:d9:dd:c25:c25b:d00a:947f
1292c19:dd:d9:dd:c25:c25b:d00a:9480/1282c19:dd:d9:dd:c25:c25b:d00a:9480
1302c19:dd:d9:dd:c25:c25b:d00a:9481/1282c19:dd:d9:dd:c25:c25b:d00a:9481
1312c19:dd:d9:dd:c25:c25b:d00a:9482/1282c19:dd:d9:dd:c25:c25b:d00a:9482
1322c19:dd:d9:dd:c25:c25b:d00a:9483/1282c19:dd:d9:dd:c25:c25b:d00a:9483
1332c19:dd:d9:dd:c25:c25b:d00a:9484/1282c19:dd:d9:dd:c25:c25b:d00a:9484
1342c19:dd:d9:dd:c25:c25b:d00a:9485/1282c19:dd:d9:dd:c25:c25b:d00a:9485
1352c19:dd:d9:dd:c25:c25b:d00a:9486/1282c19:dd:d9:dd:c25:c25b:d00a:9486
1362c19:dd:d9:dd:c25:c25b:d00a:9487/1282c19:dd:d9:dd:c25:c25b:d00a:9487
1372c19:dd:d9:dd:c25:c25b:d00a:9488/1282c19:dd:d9:dd:c25:c25b:d00a:9488
1382c19:dd:d9:dd:c25:c25b:d00a:9489/1282c19:dd:d9:dd:c25:c25b:d00a:9489
1392c19:dd:d9:dd:c25:c25b:d00a:948a/1282c19:dd:d9:dd:c25:c25b:d00a:948a
1402c19:dd:d9:dd:c25:c25b:d00a:948b/1282c19:dd:d9:dd:c25:c25b:d00a:948b
1412c19:dd:d9:dd:c25:c25b:d00a:948c/1282c19:dd:d9:dd:c25:c25b:d00a:948c
1422c19:dd:d9:dd:c25:c25b:d00a:948d/1282c19:dd:d9:dd:c25:c25b:d00a:948d
1432c19:dd:d9:dd:c25:c25b:d00a:948e/1282c19:dd:d9:dd:c25:c25b:d00a:948e
1442c19:dd:d9:dd:c25:c25b:d00a:948f/1282c19:dd:d9:dd:c25:c25b:d00a:948f
1452c19:dd:d9:dd:c25:c25b:d00a:9490/1282c19:dd:d9:dd:c25:c25b:d00a:9490
1462c19:dd:d9:dd:c25:c25b:d00a:9491/1282c19:dd:d9:dd:c25:c25b:d00a:9491
1472c19:dd:d9:dd:c25:c25b:d00a:9492/1282c19:dd:d9:dd:c25:c25b:d00a:9492
1482c19:dd:d9:dd:c25:c25b:d00a:9493/1282c19:dd:d9:dd:c25:c25b:d00a:9493
1492c19:dd:d9:dd:c25:c25b:d00a:9494/1282c19:dd:d9:dd:c25:c25b:d00a:9494
1502c19:dd:d9:dd:c25:c25b:d00a:9495/1282c19:dd:d9:dd:c25:c25b:d00a:9495
1512c19:dd:d9:dd:c25:c25b:d00a:9496/1282c19:dd:d9:dd:c25:c25b:d00a:9496
1522c19:dd:d9:dd:c25:c25b:d00a:9497/1282c19:dd:d9:dd:c25:c25b:d00a:9497
1532c19:dd:d9:dd:c25:c25b:d00a:9498/1282c19:dd:d9:dd:c25:c25b:d00a:9498
1542c19:dd:d9:dd:c25:c25b:d00a:9499/1282c19:dd:d9:dd:c25:c25b:d00a:9499
1552c19:dd:d9:dd:c25:c25b:d00a:949a/1282c19:dd:d9:dd:c25:c25b:d00a:949a
1562c19:dd:d9:dd:c25:c25b:d00a:949b/1282c19:dd:d9:dd:c25:c25b:d00a:949b
1572c19:dd:d9:dd:c25:c25b:d00a:949c/1282c19:dd:d9:dd:c25:c25b:d00a:949c
1582c19:dd:d9:dd:c25:c25b:d00a:949d/1282c19:dd:d9:dd:c25:c25b:d00a:949d
1592c19:dd:d9:dd:c25:c25b:d00a:949e/1282c19:dd:d9:dd:c25:c25b:d00a:949e
1602c19:dd:d9:dd:c25:c25b:d00a:949f/1282c19:dd:d9:dd:c25:c25b:d00a:949f
1612c19:dd:d9:dd:c25:c25b:d00a:94a0/1282c19:dd:d9:dd:c25:c25b:d00a:94a0
1622c19:dd:d9:dd:c25:c25b:d00a:94a1/1282c19:dd:d9:dd:c25:c25b:d00a:94a1
1632c19:dd:d9:dd:c25:c25b:d00a:94a2/1282c19:dd:d9:dd:c25:c25b:d00a:94a2
1642c19:dd:d9:dd:c25:c25b:d00a:94a3/1282c19:dd:d9:dd:c25:c25b:d00a:94a3
1652c19:dd:d9:dd:c25:c25b:d00a:94a4/1282c19:dd:d9:dd:c25:c25b:d00a:94a4
1662c19:dd:d9:dd:c25:c25b:d00a:94a5/1282c19:dd:d9:dd:c25:c25b:d00a:94a5
1672c19:dd:d9:dd:c25:c25b:d00a:94a6/1282c19:dd:d9:dd:c25:c25b:d00a:94a6
1682c19:dd:d9:dd:c25:c25b:d00a:94a7/1282c19:dd:d9:dd:c25:c25b:d00a:94a7
1692c19:dd:d9:dd:c25:c25b:d00a:94a8/1282c19:dd:d9:dd:c25:c25b:d00a:94a8
1702c19:dd:d9:dd:c25:c25b:d00a:94a9/1282c19:dd:d9:dd:c25:c25b:d00a:94a9
1712c19:dd:d9:dd:c25:c25b:d00a:94aa/1282c19:dd:d9:dd:c25:c25b:d00a:94aa
1722c19:dd:d9:dd:c25:c25b:d00a:94ab/1282c19:dd:d9:dd:c25:c25b:d00a:94ab
1732c19:dd:d9:dd:c25:c25b:d00a:94ac/1282c19:dd:d9:dd:c25:c25b:d00a:94ac
1742c19:dd:d9:dd:c25:c25b:d00a:94ad/1282c19:dd:d9:dd:c25:c25b:d00a:94ad
1752c19:dd:d9:dd:c25:c25b:d00a:94ae/1282c19:dd:d9:dd:c25:c25b:d00a:94ae
1762c19:dd:d9:dd:c25:c25b:d00a:94af/1282c19:dd:d9:dd:c25:c25b:d00a:94af
1772c19:dd:d9:dd:c25:c25b:d00a:94b0/1282c19:dd:d9:dd:c25:c25b:d00a:94b0
1782c19:dd:d9:dd:c25:c25b:d00a:94b1/1282c19:dd:d9:dd:c25:c25b:d00a:94b1
1792c19:dd:d9:dd:c25:c25b:d00a:94b2/1282c19:dd:d9:dd:c25:c25b:d00a:94b2
1802c19:dd:d9:dd:c25:c25b:d00a:94b3/1282c19:dd:d9:dd:c25:c25b:d00a:94b3
1812c19:dd:d9:dd:c25:c25b:d00a:94b4/1282c19:dd:d9:dd:c25:c25b:d00a:94b4
1822c19:dd:d9:dd:c25:c25b:d00a:94b5/1282c19:dd:d9:dd:c25:c25b:d00a:94b5
1832c19:dd:d9:dd:c25:c25b:d00a:94b6/1282c19:dd:d9:dd:c25:c25b:d00a:94b6
1842c19:dd:d9:dd:c25:c25b:d00a:94b7/1282c19:dd:d9:dd:c25:c25b:d00a:94b7
1852c19:dd:d9:dd:c25:c25b:d00a:94b8/1282c19:dd:d9:dd:c25:c25b:d00a:94b8
1862c19:dd:d9:dd:c25:c25b:d00a:94b9/1282c19:dd:d9:dd:c25:c25b:d00a:94b9
1872c19:dd:d9:dd:c25:c25b:d00a:94ba/1282c19:dd:d9:dd:c25:c25b:d00a:94ba
1882c19:dd:d9:dd:c25:c25b:d00a:94bb/1282c19:dd:d9:dd:c25:c25b:d00a:94bb
1892c19:dd:d9:dd:c25:c25b:d00a:94bc/1282c19:dd:d9:dd:c25:c25b:d00a:94bc
1902c19:dd:d9:dd:c25:c25b:d00a:94bd/1282c19:dd:d9:dd:c25:c25b:d00a:94bd
1912c19:dd:d9:dd:c25:c25b:d00a:94be/1282c19:dd:d9:dd:c25:c25b:d00a:94be
1922c19:dd:d9:dd:c25:c25b:d00a:94bf/1282c19:dd:d9:dd:c25:c25b:d00a:94bf
1932c19:dd:d9:dd:c25:c25b:d00a:94c0/1282c19:dd:d9:dd:c25:c25b:d00a:94c0
1942c19:dd:d9:dd:c25:c25b:d00a:94c1/1282c19:dd:d9:dd:c25:c25b:d00a:94c1
1952c19:dd:d9:dd:c25:c25b:d00a:94c2/1282c19:dd:d9:dd:c25:c25b:d00a:94c2
1962c19:dd:d9:dd:c25:c25b:d00a:94c3/1282c19:dd:d9:dd:c25:c25b:d00a:94c3
1972c19:dd:d9:dd:c25:c25b:d00a:94c4/1282c19:dd:d9:dd:c25:c25b:d00a:94c4
1982c19:dd:d9:dd:c25:c25b:d00a:94c5/1282c19:dd:d9:dd:c25:c25b:d00a:94c5
1992c19:dd:d9:dd:c25:c25b:d00a:94c6/1282c19:dd:d9:dd:c25:c25b:d00a:94c6
2002c19:dd:d9:dd:c25:c25b:d00a:94c7/1282c19:dd:d9:dd:c25:c25b:d00a:94c7
2012c19:dd:d9:dd:c25:c25b:d00a:94c8/1282c19:dd:d9:dd:c25:c25b:d00a:94c8
2022c19:dd:d9:dd:c25:c25b:d00a:94c9/1282c19:dd:d9:dd:c25:c25b:d00a:94c9
2032c19:dd:d9:dd:c25:c25b:d00a:94ca/1282c19:dd:d9:dd:c25:c25b:d00a:94ca
2042c19:dd:d9:dd:c25:c25b:d00a:94cb/1282c19:dd:d9:dd:c25:c25b:d00a:94cb
2052c19:dd:d9:dd:c25:c25b:d00a:94cc/1282c19:dd:d9:dd:c25:c25b:d00a:94cc
2062c19:dd:d9:dd:c25:c25b:d00a:94cd/1282c19:dd:d9:dd:c25:c25b:d00a:94cd
2072c19:dd:d9:dd:c25:c25b:d00a:94ce/1282c19:dd:d9:dd:c25:c25b:d00a:94ce
2082c19:dd:d9:dd:c25:c25b:d00a:94cf/1282c19:dd:d9:dd:c25:c25b:d00a:94cf
2092c19:dd:d9:dd:c25:c25b:d00a:94d0/1282c19:dd:d9:dd:c25:c25b:d00a:94d0
2102c19:dd:d9:dd:c25:c25b:d00a:94d1/1282c19:dd:d9:dd:c25:c25b:d00a:94d1
2112c19:dd:d9:dd:c25:c25b:d00a:94d2/1282c19:dd:d9:dd:c25:c25b:d00a:94d2
2122c19:dd:d9:dd:c25:c25b:d00a:94d3/1282c19:dd:d9:dd:c25:c25b:d00a:94d3
2132c19:dd:d9:dd:c25:c25b:d00a:94d4/1282c19:dd:d9:dd:c25:c25b:d00a:94d4
2142c19:dd:d9:dd:c25:c25b:d00a:94d5/1282c19:dd:d9:dd:c25:c25b:d00a:94d5
2152c19:dd:d9:dd:c25:c25b:d00a:94d6/1282c19:dd:d9:dd:c25:c25b:d00a:94d6
2162c19:dd:d9:dd:c25:c25b:d00a:94d7/1282c19:dd:d9:dd:c25:c25b:d00a:94d7
2172c19:dd:d9:dd:c25:c25b:d00a:94d8/1282c19:dd:d9:dd:c25:c25b:d00a:94d8
2182c19:dd:d9:dd:c25:c25b:d00a:94d9/1282c19:dd:d9:dd:c25:c25b:d00a:94d9
2192c19:dd:d9:dd:c25:c25b:d00a:94da/1282c19:dd:d9:dd:c25:c25b:d00a:94da
2202c19:dd:d9:dd:c25:c25b:d00a:94db/1282c19:dd:d9:dd:c25:c25b:d00a:94db
2212c19:dd:d9:dd:c25:c25b:d00a:94dc/1282c19:dd:d9:dd:c25:c25b:d00a:94dc
2222c19:dd:d9:dd:c25:c25b:d00a:94dd/1282c19:dd:d9:dd:c25:c25b:d00a:94dd
2232c19:dd:d9:dd:c25:c25b:d00a:94de/1282c19:dd:d9:dd:c25:c25b:d00a:94de
2242c19:dd:d9:dd:c25:c25b:d00a:94df/1282c19:dd:d9:dd:c25:c25b:d00a:94df
2252c19:dd:d9:dd:c25:c25b:d00a:94e0/1282c19:dd:d9:dd:c25:c25b:d00a:94e0
2262c19:dd:d9:dd:c25:c25b:d00a:94e1/1282c19:dd:d9:dd:c25:c25b:d00a:94e1
2272c19:dd:d9:dd:c25:c25b:d00a:94e2/1282c19:dd:d9:dd:c25:c25b:d00a:94e2
2282c19:dd:d9:dd:c25:c25b:d00a:94e3/1282c19:dd:d9:dd:c25:c25b:d00a:94e3
2292c19:dd:d9:dd:c25:c25b:d00a:94e4/1282c19:dd:d9:dd:c25:c25b:d00a:94e4
2302c19:dd:d9:dd:c25:c25b:d00a:94e5/1282c19:dd:d9:dd:c25:c25b:d00a:94e5
2312c19:dd:d9:dd:c25:c25b:d00a:94e6/1282c19:dd:d9:dd:c25:c25b:d00a:94e6
2322c19:dd:d9:dd:c25:c25b:d00a:94e7/1282c19:dd:d9:dd:c25:c25b:d00a:94e7
2332c19:dd:d9:dd:c25:c25b:d00a:94e8/1282c19:dd:d9:dd:c25:c25b:d00a:94e8
2342c19:dd:d9:dd:c25:c25b:d00a:94e9/1282c19:dd:d9:dd:c25:c25b:d00a:94e9
2352c19:dd:d9:dd:c25:c25b:d00a:94ea/1282c19:dd:d9:dd:c25:c25b:d00a:94ea
2362c19:dd:d9:dd:c25:c25b:d00a:94eb/1282c19:dd:d9:dd:c25:c25b:d00a:94eb
2372c19:dd:d9:dd:c25:c25b:d00a:94ec/1282c19:dd:d9:dd:c25:c25b:d00a:94ec
2382c19:dd:d9:dd:c25:c25b:d00a:94ed/1282c19:dd:d9:dd:c25:c25b:d00a:94ed
2392c19:dd:d9:dd:c25:c25b:d00a:94ee/1282c19:dd:d9:dd:c25:c25b:d00a:94ee
2402c19:dd:d9:dd:c25:c25b:d00a:94ef/1282c19:dd:d9:dd:c25:c25b:d00a:94ef
2412c19:dd:d9:dd:c25:c25b:d00a:94f0/1282c19:dd:d9:dd:c25:c25b:d00a:94f0
2422c19:dd:d9:dd:c25:c25b:d00a:94f1/1282c19:dd:d9:dd:c25:c25b:d00a:94f1
2432c19:dd:d9:dd:c25:c25b:d00a:94f2/1282c19:dd:d9:dd:c25:c25b:d00a:94f2
2442c19:dd:d9:dd:c25:c25b:d00a:94f3/1282c19:dd:d9:dd:c25:c25b:d00a:94f3
2452c19:dd:d9:dd:c25:c25b:d00a:94f4/1282c19:dd:d9:dd:c25:c25b:d00a:94f4
2462c19:dd:d9:dd:c25:c25b:d00a:94f5/1282c19:dd:d9:dd:c25:c25b:d00a:94f5
2472c19:dd:d9:dd:c25:c25b:d00a:94f6/1282c19:dd:d9:dd:c25:c25b:d00a:94f6
2482c19:dd:d9:dd:c25:c25b:d00a:94f7/1282c19:dd:d9:dd:c25:c25b:d00a:94f7
2492c19:dd:d9:dd:c25:c25b:d00a:94f8/1282c19:dd:d9:dd:c25:c25b:d00a:94f8
2502c19:dd:d9:dd:c25:c25b:d00a:94f9/1282c19:dd:d9:dd:c25:c25b:d00a:94f9
2512c19:dd:d9:dd:c25:c25b:d00a:94fa/1282c19:dd:d9:dd:c25:c25b:d00a:94fa
2522c19:dd:d9:dd:c25:c25b:d00a:94fb/1282c19:dd:d9:dd:c25:c25b:d00a:94fb
2532c19:dd:d9:dd:c25:c25b:d00a:94fc/1282c19:dd:d9:dd:c25:c25b:d00a:94fc
2542c19:dd:d9:dd:c25:c25b:d00a:94fd/1282c19:dd:d9:dd:c25:c25b:d00a:94fd
2552c19:dd:d9:dd:c25:c25b:d00a:94fe/1282c19:dd:d9:dd:c25:c25b:d00a:94fe
2562c19:dd:d9:dd:c25:c25b:d00a:94ff/1282c19:dd:d9:dd:c25:c25b:d00a:94ff

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.