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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:4400/120
First address
2c19:dd:d9:dd:c25:c25:94de:4400
Last address
2c19:dd:d9:dd:c25:c25:94de:44ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:4400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
4.4.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:4400/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:4400/1282c19:dd:d9:dd:c25:c25:94de:4400
22c19:dd:d9:dd:c25:c25:94de:4401/1282c19:dd:d9:dd:c25:c25:94de:4401
32c19:dd:d9:dd:c25:c25:94de:4402/1282c19:dd:d9:dd:c25:c25:94de:4402
42c19:dd:d9:dd:c25:c25:94de:4403/1282c19:dd:d9:dd:c25:c25:94de:4403
52c19:dd:d9:dd:c25:c25:94de:4404/1282c19:dd:d9:dd:c25:c25:94de:4404
62c19:dd:d9:dd:c25:c25:94de:4405/1282c19:dd:d9:dd:c25:c25:94de:4405
72c19:dd:d9:dd:c25:c25:94de:4406/1282c19:dd:d9:dd:c25:c25:94de:4406
82c19:dd:d9:dd:c25:c25:94de:4407/1282c19:dd:d9:dd:c25:c25:94de:4407
92c19:dd:d9:dd:c25:c25:94de:4408/1282c19:dd:d9:dd:c25:c25:94de:4408
102c19:dd:d9:dd:c25:c25:94de:4409/1282c19:dd:d9:dd:c25:c25:94de:4409
112c19:dd:d9:dd:c25:c25:94de:440a/1282c19:dd:d9:dd:c25:c25:94de:440a
122c19:dd:d9:dd:c25:c25:94de:440b/1282c19:dd:d9:dd:c25:c25:94de:440b
132c19:dd:d9:dd:c25:c25:94de:440c/1282c19:dd:d9:dd:c25:c25:94de:440c
142c19:dd:d9:dd:c25:c25:94de:440d/1282c19:dd:d9:dd:c25:c25:94de:440d
152c19:dd:d9:dd:c25:c25:94de:440e/1282c19:dd:d9:dd:c25:c25:94de:440e
162c19:dd:d9:dd:c25:c25:94de:440f/1282c19:dd:d9:dd:c25:c25:94de:440f
172c19:dd:d9:dd:c25:c25:94de:4410/1282c19:dd:d9:dd:c25:c25:94de:4410
182c19:dd:d9:dd:c25:c25:94de:4411/1282c19:dd:d9:dd:c25:c25:94de:4411
192c19:dd:d9:dd:c25:c25:94de:4412/1282c19:dd:d9:dd:c25:c25:94de:4412
202c19:dd:d9:dd:c25:c25:94de:4413/1282c19:dd:d9:dd:c25:c25:94de:4413
212c19:dd:d9:dd:c25:c25:94de:4414/1282c19:dd:d9:dd:c25:c25:94de:4414
222c19:dd:d9:dd:c25:c25:94de:4415/1282c19:dd:d9:dd:c25:c25:94de:4415
232c19:dd:d9:dd:c25:c25:94de:4416/1282c19:dd:d9:dd:c25:c25:94de:4416
242c19:dd:d9:dd:c25:c25:94de:4417/1282c19:dd:d9:dd:c25:c25:94de:4417
252c19:dd:d9:dd:c25:c25:94de:4418/1282c19:dd:d9:dd:c25:c25:94de:4418
262c19:dd:d9:dd:c25:c25:94de:4419/1282c19:dd:d9:dd:c25:c25:94de:4419
272c19:dd:d9:dd:c25:c25:94de:441a/1282c19:dd:d9:dd:c25:c25:94de:441a
282c19:dd:d9:dd:c25:c25:94de:441b/1282c19:dd:d9:dd:c25:c25:94de:441b
292c19:dd:d9:dd:c25:c25:94de:441c/1282c19:dd:d9:dd:c25:c25:94de:441c
302c19:dd:d9:dd:c25:c25:94de:441d/1282c19:dd:d9:dd:c25:c25:94de:441d
312c19:dd:d9:dd:c25:c25:94de:441e/1282c19:dd:d9:dd:c25:c25:94de:441e
322c19:dd:d9:dd:c25:c25:94de:441f/1282c19:dd:d9:dd:c25:c25:94de:441f
332c19:dd:d9:dd:c25:c25:94de:4420/1282c19:dd:d9:dd:c25:c25:94de:4420
342c19:dd:d9:dd:c25:c25:94de:4421/1282c19:dd:d9:dd:c25:c25:94de:4421
352c19:dd:d9:dd:c25:c25:94de:4422/1282c19:dd:d9:dd:c25:c25:94de:4422
362c19:dd:d9:dd:c25:c25:94de:4423/1282c19:dd:d9:dd:c25:c25:94de:4423
372c19:dd:d9:dd:c25:c25:94de:4424/1282c19:dd:d9:dd:c25:c25:94de:4424
382c19:dd:d9:dd:c25:c25:94de:4425/1282c19:dd:d9:dd:c25:c25:94de:4425
392c19:dd:d9:dd:c25:c25:94de:4426/1282c19:dd:d9:dd:c25:c25:94de:4426
402c19:dd:d9:dd:c25:c25:94de:4427/1282c19:dd:d9:dd:c25:c25:94de:4427
412c19:dd:d9:dd:c25:c25:94de:4428/1282c19:dd:d9:dd:c25:c25:94de:4428
422c19:dd:d9:dd:c25:c25:94de:4429/1282c19:dd:d9:dd:c25:c25:94de:4429
432c19:dd:d9:dd:c25:c25:94de:442a/1282c19:dd:d9:dd:c25:c25:94de:442a
442c19:dd:d9:dd:c25:c25:94de:442b/1282c19:dd:d9:dd:c25:c25:94de:442b
452c19:dd:d9:dd:c25:c25:94de:442c/1282c19:dd:d9:dd:c25:c25:94de:442c
462c19:dd:d9:dd:c25:c25:94de:442d/1282c19:dd:d9:dd:c25:c25:94de:442d
472c19:dd:d9:dd:c25:c25:94de:442e/1282c19:dd:d9:dd:c25:c25:94de:442e
482c19:dd:d9:dd:c25:c25:94de:442f/1282c19:dd:d9:dd:c25:c25:94de:442f
492c19:dd:d9:dd:c25:c25:94de:4430/1282c19:dd:d9:dd:c25:c25:94de:4430
502c19:dd:d9:dd:c25:c25:94de:4431/1282c19:dd:d9:dd:c25:c25:94de:4431
512c19:dd:d9:dd:c25:c25:94de:4432/1282c19:dd:d9:dd:c25:c25:94de:4432
522c19:dd:d9:dd:c25:c25:94de:4433/1282c19:dd:d9:dd:c25:c25:94de:4433
532c19:dd:d9:dd:c25:c25:94de:4434/1282c19:dd:d9:dd:c25:c25:94de:4434
542c19:dd:d9:dd:c25:c25:94de:4435/1282c19:dd:d9:dd:c25:c25:94de:4435
552c19:dd:d9:dd:c25:c25:94de:4436/1282c19:dd:d9:dd:c25:c25:94de:4436
562c19:dd:d9:dd:c25:c25:94de:4437/1282c19:dd:d9:dd:c25:c25:94de:4437
572c19:dd:d9:dd:c25:c25:94de:4438/1282c19:dd:d9:dd:c25:c25:94de:4438
582c19:dd:d9:dd:c25:c25:94de:4439/1282c19:dd:d9:dd:c25:c25:94de:4439
592c19:dd:d9:dd:c25:c25:94de:443a/1282c19:dd:d9:dd:c25:c25:94de:443a
602c19:dd:d9:dd:c25:c25:94de:443b/1282c19:dd:d9:dd:c25:c25:94de:443b
612c19:dd:d9:dd:c25:c25:94de:443c/1282c19:dd:d9:dd:c25:c25:94de:443c
622c19:dd:d9:dd:c25:c25:94de:443d/1282c19:dd:d9:dd:c25:c25:94de:443d
632c19:dd:d9:dd:c25:c25:94de:443e/1282c19:dd:d9:dd:c25:c25:94de:443e
642c19:dd:d9:dd:c25:c25:94de:443f/1282c19:dd:d9:dd:c25:c25:94de:443f
652c19:dd:d9:dd:c25:c25:94de:4440/1282c19:dd:d9:dd:c25:c25:94de:4440
662c19:dd:d9:dd:c25:c25:94de:4441/1282c19:dd:d9:dd:c25:c25:94de:4441
672c19:dd:d9:dd:c25:c25:94de:4442/1282c19:dd:d9:dd:c25:c25:94de:4442
682c19:dd:d9:dd:c25:c25:94de:4443/1282c19:dd:d9:dd:c25:c25:94de:4443
692c19:dd:d9:dd:c25:c25:94de:4444/1282c19:dd:d9:dd:c25:c25:94de:4444
702c19:dd:d9:dd:c25:c25:94de:4445/1282c19:dd:d9:dd:c25:c25:94de:4445
712c19:dd:d9:dd:c25:c25:94de:4446/1282c19:dd:d9:dd:c25:c25:94de:4446
722c19:dd:d9:dd:c25:c25:94de:4447/1282c19:dd:d9:dd:c25:c25:94de:4447
732c19:dd:d9:dd:c25:c25:94de:4448/1282c19:dd:d9:dd:c25:c25:94de:4448
742c19:dd:d9:dd:c25:c25:94de:4449/1282c19:dd:d9:dd:c25:c25:94de:4449
752c19:dd:d9:dd:c25:c25:94de:444a/1282c19:dd:d9:dd:c25:c25:94de:444a
762c19:dd:d9:dd:c25:c25:94de:444b/1282c19:dd:d9:dd:c25:c25:94de:444b
772c19:dd:d9:dd:c25:c25:94de:444c/1282c19:dd:d9:dd:c25:c25:94de:444c
782c19:dd:d9:dd:c25:c25:94de:444d/1282c19:dd:d9:dd:c25:c25:94de:444d
792c19:dd:d9:dd:c25:c25:94de:444e/1282c19:dd:d9:dd:c25:c25:94de:444e
802c19:dd:d9:dd:c25:c25:94de:444f/1282c19:dd:d9:dd:c25:c25:94de:444f
812c19:dd:d9:dd:c25:c25:94de:4450/1282c19:dd:d9:dd:c25:c25:94de:4450
822c19:dd:d9:dd:c25:c25:94de:4451/1282c19:dd:d9:dd:c25:c25:94de:4451
832c19:dd:d9:dd:c25:c25:94de:4452/1282c19:dd:d9:dd:c25:c25:94de:4452
842c19:dd:d9:dd:c25:c25:94de:4453/1282c19:dd:d9:dd:c25:c25:94de:4453
852c19:dd:d9:dd:c25:c25:94de:4454/1282c19:dd:d9:dd:c25:c25:94de:4454
862c19:dd:d9:dd:c25:c25:94de:4455/1282c19:dd:d9:dd:c25:c25:94de:4455
872c19:dd:d9:dd:c25:c25:94de:4456/1282c19:dd:d9:dd:c25:c25:94de:4456
882c19:dd:d9:dd:c25:c25:94de:4457/1282c19:dd:d9:dd:c25:c25:94de:4457
892c19:dd:d9:dd:c25:c25:94de:4458/1282c19:dd:d9:dd:c25:c25:94de:4458
902c19:dd:d9:dd:c25:c25:94de:4459/1282c19:dd:d9:dd:c25:c25:94de:4459
912c19:dd:d9:dd:c25:c25:94de:445a/1282c19:dd:d9:dd:c25:c25:94de:445a
922c19:dd:d9:dd:c25:c25:94de:445b/1282c19:dd:d9:dd:c25:c25:94de:445b
932c19:dd:d9:dd:c25:c25:94de:445c/1282c19:dd:d9:dd:c25:c25:94de:445c
942c19:dd:d9:dd:c25:c25:94de:445d/1282c19:dd:d9:dd:c25:c25:94de:445d
952c19:dd:d9:dd:c25:c25:94de:445e/1282c19:dd:d9:dd:c25:c25:94de:445e
962c19:dd:d9:dd:c25:c25:94de:445f/1282c19:dd:d9:dd:c25:c25:94de:445f
972c19:dd:d9:dd:c25:c25:94de:4460/1282c19:dd:d9:dd:c25:c25:94de:4460
982c19:dd:d9:dd:c25:c25:94de:4461/1282c19:dd:d9:dd:c25:c25:94de:4461
992c19:dd:d9:dd:c25:c25:94de:4462/1282c19:dd:d9:dd:c25:c25:94de:4462
1002c19:dd:d9:dd:c25:c25:94de:4463/1282c19:dd:d9:dd:c25:c25:94de:4463
1012c19:dd:d9:dd:c25:c25:94de:4464/1282c19:dd:d9:dd:c25:c25:94de:4464
1022c19:dd:d9:dd:c25:c25:94de:4465/1282c19:dd:d9:dd:c25:c25:94de:4465
1032c19:dd:d9:dd:c25:c25:94de:4466/1282c19:dd:d9:dd:c25:c25:94de:4466
1042c19:dd:d9:dd:c25:c25:94de:4467/1282c19:dd:d9:dd:c25:c25:94de:4467
1052c19:dd:d9:dd:c25:c25:94de:4468/1282c19:dd:d9:dd:c25:c25:94de:4468
1062c19:dd:d9:dd:c25:c25:94de:4469/1282c19:dd:d9:dd:c25:c25:94de:4469
1072c19:dd:d9:dd:c25:c25:94de:446a/1282c19:dd:d9:dd:c25:c25:94de:446a
1082c19:dd:d9:dd:c25:c25:94de:446b/1282c19:dd:d9:dd:c25:c25:94de:446b
1092c19:dd:d9:dd:c25:c25:94de:446c/1282c19:dd:d9:dd:c25:c25:94de:446c
1102c19:dd:d9:dd:c25:c25:94de:446d/1282c19:dd:d9:dd:c25:c25:94de:446d
1112c19:dd:d9:dd:c25:c25:94de:446e/1282c19:dd:d9:dd:c25:c25:94de:446e
1122c19:dd:d9:dd:c25:c25:94de:446f/1282c19:dd:d9:dd:c25:c25:94de:446f
1132c19:dd:d9:dd:c25:c25:94de:4470/1282c19:dd:d9:dd:c25:c25:94de:4470
1142c19:dd:d9:dd:c25:c25:94de:4471/1282c19:dd:d9:dd:c25:c25:94de:4471
1152c19:dd:d9:dd:c25:c25:94de:4472/1282c19:dd:d9:dd:c25:c25:94de:4472
1162c19:dd:d9:dd:c25:c25:94de:4473/1282c19:dd:d9:dd:c25:c25:94de:4473
1172c19:dd:d9:dd:c25:c25:94de:4474/1282c19:dd:d9:dd:c25:c25:94de:4474
1182c19:dd:d9:dd:c25:c25:94de:4475/1282c19:dd:d9:dd:c25:c25:94de:4475
1192c19:dd:d9:dd:c25:c25:94de:4476/1282c19:dd:d9:dd:c25:c25:94de:4476
1202c19:dd:d9:dd:c25:c25:94de:4477/1282c19:dd:d9:dd:c25:c25:94de:4477
1212c19:dd:d9:dd:c25:c25:94de:4478/1282c19:dd:d9:dd:c25:c25:94de:4478
1222c19:dd:d9:dd:c25:c25:94de:4479/1282c19:dd:d9:dd:c25:c25:94de:4479
1232c19:dd:d9:dd:c25:c25:94de:447a/1282c19:dd:d9:dd:c25:c25:94de:447a
1242c19:dd:d9:dd:c25:c25:94de:447b/1282c19:dd:d9:dd:c25:c25:94de:447b
1252c19:dd:d9:dd:c25:c25:94de:447c/1282c19:dd:d9:dd:c25:c25:94de:447c
1262c19:dd:d9:dd:c25:c25:94de:447d/1282c19:dd:d9:dd:c25:c25:94de:447d
1272c19:dd:d9:dd:c25:c25:94de:447e/1282c19:dd:d9:dd:c25:c25:94de:447e
1282c19:dd:d9:dd:c25:c25:94de:447f/1282c19:dd:d9:dd:c25:c25:94de:447f
1292c19:dd:d9:dd:c25:c25:94de:4480/1282c19:dd:d9:dd:c25:c25:94de:4480
1302c19:dd:d9:dd:c25:c25:94de:4481/1282c19:dd:d9:dd:c25:c25:94de:4481
1312c19:dd:d9:dd:c25:c25:94de:4482/1282c19:dd:d9:dd:c25:c25:94de:4482
1322c19:dd:d9:dd:c25:c25:94de:4483/1282c19:dd:d9:dd:c25:c25:94de:4483
1332c19:dd:d9:dd:c25:c25:94de:4484/1282c19:dd:d9:dd:c25:c25:94de:4484
1342c19:dd:d9:dd:c25:c25:94de:4485/1282c19:dd:d9:dd:c25:c25:94de:4485
1352c19:dd:d9:dd:c25:c25:94de:4486/1282c19:dd:d9:dd:c25:c25:94de:4486
1362c19:dd:d9:dd:c25:c25:94de:4487/1282c19:dd:d9:dd:c25:c25:94de:4487
1372c19:dd:d9:dd:c25:c25:94de:4488/1282c19:dd:d9:dd:c25:c25:94de:4488
1382c19:dd:d9:dd:c25:c25:94de:4489/1282c19:dd:d9:dd:c25:c25:94de:4489
1392c19:dd:d9:dd:c25:c25:94de:448a/1282c19:dd:d9:dd:c25:c25:94de:448a
1402c19:dd:d9:dd:c25:c25:94de:448b/1282c19:dd:d9:dd:c25:c25:94de:448b
1412c19:dd:d9:dd:c25:c25:94de:448c/1282c19:dd:d9:dd:c25:c25:94de:448c
1422c19:dd:d9:dd:c25:c25:94de:448d/1282c19:dd:d9:dd:c25:c25:94de:448d
1432c19:dd:d9:dd:c25:c25:94de:448e/1282c19:dd:d9:dd:c25:c25:94de:448e
1442c19:dd:d9:dd:c25:c25:94de:448f/1282c19:dd:d9:dd:c25:c25:94de:448f
1452c19:dd:d9:dd:c25:c25:94de:4490/1282c19:dd:d9:dd:c25:c25:94de:4490
1462c19:dd:d9:dd:c25:c25:94de:4491/1282c19:dd:d9:dd:c25:c25:94de:4491
1472c19:dd:d9:dd:c25:c25:94de:4492/1282c19:dd:d9:dd:c25:c25:94de:4492
1482c19:dd:d9:dd:c25:c25:94de:4493/1282c19:dd:d9:dd:c25:c25:94de:4493
1492c19:dd:d9:dd:c25:c25:94de:4494/1282c19:dd:d9:dd:c25:c25:94de:4494
1502c19:dd:d9:dd:c25:c25:94de:4495/1282c19:dd:d9:dd:c25:c25:94de:4495
1512c19:dd:d9:dd:c25:c25:94de:4496/1282c19:dd:d9:dd:c25:c25:94de:4496
1522c19:dd:d9:dd:c25:c25:94de:4497/1282c19:dd:d9:dd:c25:c25:94de:4497
1532c19:dd:d9:dd:c25:c25:94de:4498/1282c19:dd:d9:dd:c25:c25:94de:4498
1542c19:dd:d9:dd:c25:c25:94de:4499/1282c19:dd:d9:dd:c25:c25:94de:4499
1552c19:dd:d9:dd:c25:c25:94de:449a/1282c19:dd:d9:dd:c25:c25:94de:449a
1562c19:dd:d9:dd:c25:c25:94de:449b/1282c19:dd:d9:dd:c25:c25:94de:449b
1572c19:dd:d9:dd:c25:c25:94de:449c/1282c19:dd:d9:dd:c25:c25:94de:449c
1582c19:dd:d9:dd:c25:c25:94de:449d/1282c19:dd:d9:dd:c25:c25:94de:449d
1592c19:dd:d9:dd:c25:c25:94de:449e/1282c19:dd:d9:dd:c25:c25:94de:449e
1602c19:dd:d9:dd:c25:c25:94de:449f/1282c19:dd:d9:dd:c25:c25:94de:449f
1612c19:dd:d9:dd:c25:c25:94de:44a0/1282c19:dd:d9:dd:c25:c25:94de:44a0
1622c19:dd:d9:dd:c25:c25:94de:44a1/1282c19:dd:d9:dd:c25:c25:94de:44a1
1632c19:dd:d9:dd:c25:c25:94de:44a2/1282c19:dd:d9:dd:c25:c25:94de:44a2
1642c19:dd:d9:dd:c25:c25:94de:44a3/1282c19:dd:d9:dd:c25:c25:94de:44a3
1652c19:dd:d9:dd:c25:c25:94de:44a4/1282c19:dd:d9:dd:c25:c25:94de:44a4
1662c19:dd:d9:dd:c25:c25:94de:44a5/1282c19:dd:d9:dd:c25:c25:94de:44a5
1672c19:dd:d9:dd:c25:c25:94de:44a6/1282c19:dd:d9:dd:c25:c25:94de:44a6
1682c19:dd:d9:dd:c25:c25:94de:44a7/1282c19:dd:d9:dd:c25:c25:94de:44a7
1692c19:dd:d9:dd:c25:c25:94de:44a8/1282c19:dd:d9:dd:c25:c25:94de:44a8
1702c19:dd:d9:dd:c25:c25:94de:44a9/1282c19:dd:d9:dd:c25:c25:94de:44a9
1712c19:dd:d9:dd:c25:c25:94de:44aa/1282c19:dd:d9:dd:c25:c25:94de:44aa
1722c19:dd:d9:dd:c25:c25:94de:44ab/1282c19:dd:d9:dd:c25:c25:94de:44ab
1732c19:dd:d9:dd:c25:c25:94de:44ac/1282c19:dd:d9:dd:c25:c25:94de:44ac
1742c19:dd:d9:dd:c25:c25:94de:44ad/1282c19:dd:d9:dd:c25:c25:94de:44ad
1752c19:dd:d9:dd:c25:c25:94de:44ae/1282c19:dd:d9:dd:c25:c25:94de:44ae
1762c19:dd:d9:dd:c25:c25:94de:44af/1282c19:dd:d9:dd:c25:c25:94de:44af
1772c19:dd:d9:dd:c25:c25:94de:44b0/1282c19:dd:d9:dd:c25:c25:94de:44b0
1782c19:dd:d9:dd:c25:c25:94de:44b1/1282c19:dd:d9:dd:c25:c25:94de:44b1
1792c19:dd:d9:dd:c25:c25:94de:44b2/1282c19:dd:d9:dd:c25:c25:94de:44b2
1802c19:dd:d9:dd:c25:c25:94de:44b3/1282c19:dd:d9:dd:c25:c25:94de:44b3
1812c19:dd:d9:dd:c25:c25:94de:44b4/1282c19:dd:d9:dd:c25:c25:94de:44b4
1822c19:dd:d9:dd:c25:c25:94de:44b5/1282c19:dd:d9:dd:c25:c25:94de:44b5
1832c19:dd:d9:dd:c25:c25:94de:44b6/1282c19:dd:d9:dd:c25:c25:94de:44b6
1842c19:dd:d9:dd:c25:c25:94de:44b7/1282c19:dd:d9:dd:c25:c25:94de:44b7
1852c19:dd:d9:dd:c25:c25:94de:44b8/1282c19:dd:d9:dd:c25:c25:94de:44b8
1862c19:dd:d9:dd:c25:c25:94de:44b9/1282c19:dd:d9:dd:c25:c25:94de:44b9
1872c19:dd:d9:dd:c25:c25:94de:44ba/1282c19:dd:d9:dd:c25:c25:94de:44ba
1882c19:dd:d9:dd:c25:c25:94de:44bb/1282c19:dd:d9:dd:c25:c25:94de:44bb
1892c19:dd:d9:dd:c25:c25:94de:44bc/1282c19:dd:d9:dd:c25:c25:94de:44bc
1902c19:dd:d9:dd:c25:c25:94de:44bd/1282c19:dd:d9:dd:c25:c25:94de:44bd
1912c19:dd:d9:dd:c25:c25:94de:44be/1282c19:dd:d9:dd:c25:c25:94de:44be
1922c19:dd:d9:dd:c25:c25:94de:44bf/1282c19:dd:d9:dd:c25:c25:94de:44bf
1932c19:dd:d9:dd:c25:c25:94de:44c0/1282c19:dd:d9:dd:c25:c25:94de:44c0
1942c19:dd:d9:dd:c25:c25:94de:44c1/1282c19:dd:d9:dd:c25:c25:94de:44c1
1952c19:dd:d9:dd:c25:c25:94de:44c2/1282c19:dd:d9:dd:c25:c25:94de:44c2
1962c19:dd:d9:dd:c25:c25:94de:44c3/1282c19:dd:d9:dd:c25:c25:94de:44c3
1972c19:dd:d9:dd:c25:c25:94de:44c4/1282c19:dd:d9:dd:c25:c25:94de:44c4
1982c19:dd:d9:dd:c25:c25:94de:44c5/1282c19:dd:d9:dd:c25:c25:94de:44c5
1992c19:dd:d9:dd:c25:c25:94de:44c6/1282c19:dd:d9:dd:c25:c25:94de:44c6
2002c19:dd:d9:dd:c25:c25:94de:44c7/1282c19:dd:d9:dd:c25:c25:94de:44c7
2012c19:dd:d9:dd:c25:c25:94de:44c8/1282c19:dd:d9:dd:c25:c25:94de:44c8
2022c19:dd:d9:dd:c25:c25:94de:44c9/1282c19:dd:d9:dd:c25:c25:94de:44c9
2032c19:dd:d9:dd:c25:c25:94de:44ca/1282c19:dd:d9:dd:c25:c25:94de:44ca
2042c19:dd:d9:dd:c25:c25:94de:44cb/1282c19:dd:d9:dd:c25:c25:94de:44cb
2052c19:dd:d9:dd:c25:c25:94de:44cc/1282c19:dd:d9:dd:c25:c25:94de:44cc
2062c19:dd:d9:dd:c25:c25:94de:44cd/1282c19:dd:d9:dd:c25:c25:94de:44cd
2072c19:dd:d9:dd:c25:c25:94de:44ce/1282c19:dd:d9:dd:c25:c25:94de:44ce
2082c19:dd:d9:dd:c25:c25:94de:44cf/1282c19:dd:d9:dd:c25:c25:94de:44cf
2092c19:dd:d9:dd:c25:c25:94de:44d0/1282c19:dd:d9:dd:c25:c25:94de:44d0
2102c19:dd:d9:dd:c25:c25:94de:44d1/1282c19:dd:d9:dd:c25:c25:94de:44d1
2112c19:dd:d9:dd:c25:c25:94de:44d2/1282c19:dd:d9:dd:c25:c25:94de:44d2
2122c19:dd:d9:dd:c25:c25:94de:44d3/1282c19:dd:d9:dd:c25:c25:94de:44d3
2132c19:dd:d9:dd:c25:c25:94de:44d4/1282c19:dd:d9:dd:c25:c25:94de:44d4
2142c19:dd:d9:dd:c25:c25:94de:44d5/1282c19:dd:d9:dd:c25:c25:94de:44d5
2152c19:dd:d9:dd:c25:c25:94de:44d6/1282c19:dd:d9:dd:c25:c25:94de:44d6
2162c19:dd:d9:dd:c25:c25:94de:44d7/1282c19:dd:d9:dd:c25:c25:94de:44d7
2172c19:dd:d9:dd:c25:c25:94de:44d8/1282c19:dd:d9:dd:c25:c25:94de:44d8
2182c19:dd:d9:dd:c25:c25:94de:44d9/1282c19:dd:d9:dd:c25:c25:94de:44d9
2192c19:dd:d9:dd:c25:c25:94de:44da/1282c19:dd:d9:dd:c25:c25:94de:44da
2202c19:dd:d9:dd:c25:c25:94de:44db/1282c19:dd:d9:dd:c25:c25:94de:44db
2212c19:dd:d9:dd:c25:c25:94de:44dc/1282c19:dd:d9:dd:c25:c25:94de:44dc
2222c19:dd:d9:dd:c25:c25:94de:44dd/1282c19:dd:d9:dd:c25:c25:94de:44dd
2232c19:dd:d9:dd:c25:c25:94de:44de/1282c19:dd:d9:dd:c25:c25:94de:44de
2242c19:dd:d9:dd:c25:c25:94de:44df/1282c19:dd:d9:dd:c25:c25:94de:44df
2252c19:dd:d9:dd:c25:c25:94de:44e0/1282c19:dd:d9:dd:c25:c25:94de:44e0
2262c19:dd:d9:dd:c25:c25:94de:44e1/1282c19:dd:d9:dd:c25:c25:94de:44e1
2272c19:dd:d9:dd:c25:c25:94de:44e2/1282c19:dd:d9:dd:c25:c25:94de:44e2
2282c19:dd:d9:dd:c25:c25:94de:44e3/1282c19:dd:d9:dd:c25:c25:94de:44e3
2292c19:dd:d9:dd:c25:c25:94de:44e4/1282c19:dd:d9:dd:c25:c25:94de:44e4
2302c19:dd:d9:dd:c25:c25:94de:44e5/1282c19:dd:d9:dd:c25:c25:94de:44e5
2312c19:dd:d9:dd:c25:c25:94de:44e6/1282c19:dd:d9:dd:c25:c25:94de:44e6
2322c19:dd:d9:dd:c25:c25:94de:44e7/1282c19:dd:d9:dd:c25:c25:94de:44e7
2332c19:dd:d9:dd:c25:c25:94de:44e8/1282c19:dd:d9:dd:c25:c25:94de:44e8
2342c19:dd:d9:dd:c25:c25:94de:44e9/1282c19:dd:d9:dd:c25:c25:94de:44e9
2352c19:dd:d9:dd:c25:c25:94de:44ea/1282c19:dd:d9:dd:c25:c25:94de:44ea
2362c19:dd:d9:dd:c25:c25:94de:44eb/1282c19:dd:d9:dd:c25:c25:94de:44eb
2372c19:dd:d9:dd:c25:c25:94de:44ec/1282c19:dd:d9:dd:c25:c25:94de:44ec
2382c19:dd:d9:dd:c25:c25:94de:44ed/1282c19:dd:d9:dd:c25:c25:94de:44ed
2392c19:dd:d9:dd:c25:c25:94de:44ee/1282c19:dd:d9:dd:c25:c25:94de:44ee
2402c19:dd:d9:dd:c25:c25:94de:44ef/1282c19:dd:d9:dd:c25:c25:94de:44ef
2412c19:dd:d9:dd:c25:c25:94de:44f0/1282c19:dd:d9:dd:c25:c25:94de:44f0
2422c19:dd:d9:dd:c25:c25:94de:44f1/1282c19:dd:d9:dd:c25:c25:94de:44f1
2432c19:dd:d9:dd:c25:c25:94de:44f2/1282c19:dd:d9:dd:c25:c25:94de:44f2
2442c19:dd:d9:dd:c25:c25:94de:44f3/1282c19:dd:d9:dd:c25:c25:94de:44f3
2452c19:dd:d9:dd:c25:c25:94de:44f4/1282c19:dd:d9:dd:c25:c25:94de:44f4
2462c19:dd:d9:dd:c25:c25:94de:44f5/1282c19:dd:d9:dd:c25:c25:94de:44f5
2472c19:dd:d9:dd:c25:c25:94de:44f6/1282c19:dd:d9:dd:c25:c25:94de:44f6
2482c19:dd:d9:dd:c25:c25:94de:44f7/1282c19:dd:d9:dd:c25:c25:94de:44f7
2492c19:dd:d9:dd:c25:c25:94de:44f8/1282c19:dd:d9:dd:c25:c25:94de:44f8
2502c19:dd:d9:dd:c25:c25:94de:44f9/1282c19:dd:d9:dd:c25:c25:94de:44f9
2512c19:dd:d9:dd:c25:c25:94de:44fa/1282c19:dd:d9:dd:c25:c25:94de:44fa
2522c19:dd:d9:dd:c25:c25:94de:44fb/1282c19:dd:d9:dd:c25:c25:94de:44fb
2532c19:dd:d9:dd:c25:c25:94de:44fc/1282c19:dd:d9:dd:c25:c25:94de:44fc
2542c19:dd:d9:dd:c25:c25:94de:44fd/1282c19:dd:d9:dd:c25:c25:94de:44fd
2552c19:dd:d9:dd:c25:c25:94de:44fe/1282c19:dd:d9:dd:c25:c25:94de:44fe
2562c19:dd:d9:dd:c25:c25:94de:44ff/1282c19:dd:d9:dd:c25:c25:94de:44ff

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.