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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:5300/120
First address
2c19:dd:d9:dd:c25:c25:94de:5300
Last address
2c19:dd:d9:dd:c25:c25:94de:53ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:5300
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.5.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:5300/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:5300/1282c19:dd:d9:dd:c25:c25:94de:5300
22c19:dd:d9:dd:c25:c25:94de:5301/1282c19:dd:d9:dd:c25:c25:94de:5301
32c19:dd:d9:dd:c25:c25:94de:5302/1282c19:dd:d9:dd:c25:c25:94de:5302
42c19:dd:d9:dd:c25:c25:94de:5303/1282c19:dd:d9:dd:c25:c25:94de:5303
52c19:dd:d9:dd:c25:c25:94de:5304/1282c19:dd:d9:dd:c25:c25:94de:5304
62c19:dd:d9:dd:c25:c25:94de:5305/1282c19:dd:d9:dd:c25:c25:94de:5305
72c19:dd:d9:dd:c25:c25:94de:5306/1282c19:dd:d9:dd:c25:c25:94de:5306
82c19:dd:d9:dd:c25:c25:94de:5307/1282c19:dd:d9:dd:c25:c25:94de:5307
92c19:dd:d9:dd:c25:c25:94de:5308/1282c19:dd:d9:dd:c25:c25:94de:5308
102c19:dd:d9:dd:c25:c25:94de:5309/1282c19:dd:d9:dd:c25:c25:94de:5309
112c19:dd:d9:dd:c25:c25:94de:530a/1282c19:dd:d9:dd:c25:c25:94de:530a
122c19:dd:d9:dd:c25:c25:94de:530b/1282c19:dd:d9:dd:c25:c25:94de:530b
132c19:dd:d9:dd:c25:c25:94de:530c/1282c19:dd:d9:dd:c25:c25:94de:530c
142c19:dd:d9:dd:c25:c25:94de:530d/1282c19:dd:d9:dd:c25:c25:94de:530d
152c19:dd:d9:dd:c25:c25:94de:530e/1282c19:dd:d9:dd:c25:c25:94de:530e
162c19:dd:d9:dd:c25:c25:94de:530f/1282c19:dd:d9:dd:c25:c25:94de:530f
172c19:dd:d9:dd:c25:c25:94de:5310/1282c19:dd:d9:dd:c25:c25:94de:5310
182c19:dd:d9:dd:c25:c25:94de:5311/1282c19:dd:d9:dd:c25:c25:94de:5311
192c19:dd:d9:dd:c25:c25:94de:5312/1282c19:dd:d9:dd:c25:c25:94de:5312
202c19:dd:d9:dd:c25:c25:94de:5313/1282c19:dd:d9:dd:c25:c25:94de:5313
212c19:dd:d9:dd:c25:c25:94de:5314/1282c19:dd:d9:dd:c25:c25:94de:5314
222c19:dd:d9:dd:c25:c25:94de:5315/1282c19:dd:d9:dd:c25:c25:94de:5315
232c19:dd:d9:dd:c25:c25:94de:5316/1282c19:dd:d9:dd:c25:c25:94de:5316
242c19:dd:d9:dd:c25:c25:94de:5317/1282c19:dd:d9:dd:c25:c25:94de:5317
252c19:dd:d9:dd:c25:c25:94de:5318/1282c19:dd:d9:dd:c25:c25:94de:5318
262c19:dd:d9:dd:c25:c25:94de:5319/1282c19:dd:d9:dd:c25:c25:94de:5319
272c19:dd:d9:dd:c25:c25:94de:531a/1282c19:dd:d9:dd:c25:c25:94de:531a
282c19:dd:d9:dd:c25:c25:94de:531b/1282c19:dd:d9:dd:c25:c25:94de:531b
292c19:dd:d9:dd:c25:c25:94de:531c/1282c19:dd:d9:dd:c25:c25:94de:531c
302c19:dd:d9:dd:c25:c25:94de:531d/1282c19:dd:d9:dd:c25:c25:94de:531d
312c19:dd:d9:dd:c25:c25:94de:531e/1282c19:dd:d9:dd:c25:c25:94de:531e
322c19:dd:d9:dd:c25:c25:94de:531f/1282c19:dd:d9:dd:c25:c25:94de:531f
332c19:dd:d9:dd:c25:c25:94de:5320/1282c19:dd:d9:dd:c25:c25:94de:5320
342c19:dd:d9:dd:c25:c25:94de:5321/1282c19:dd:d9:dd:c25:c25:94de:5321
352c19:dd:d9:dd:c25:c25:94de:5322/1282c19:dd:d9:dd:c25:c25:94de:5322
362c19:dd:d9:dd:c25:c25:94de:5323/1282c19:dd:d9:dd:c25:c25:94de:5323
372c19:dd:d9:dd:c25:c25:94de:5324/1282c19:dd:d9:dd:c25:c25:94de:5324
382c19:dd:d9:dd:c25:c25:94de:5325/1282c19:dd:d9:dd:c25:c25:94de:5325
392c19:dd:d9:dd:c25:c25:94de:5326/1282c19:dd:d9:dd:c25:c25:94de:5326
402c19:dd:d9:dd:c25:c25:94de:5327/1282c19:dd:d9:dd:c25:c25:94de:5327
412c19:dd:d9:dd:c25:c25:94de:5328/1282c19:dd:d9:dd:c25:c25:94de:5328
422c19:dd:d9:dd:c25:c25:94de:5329/1282c19:dd:d9:dd:c25:c25:94de:5329
432c19:dd:d9:dd:c25:c25:94de:532a/1282c19:dd:d9:dd:c25:c25:94de:532a
442c19:dd:d9:dd:c25:c25:94de:532b/1282c19:dd:d9:dd:c25:c25:94de:532b
452c19:dd:d9:dd:c25:c25:94de:532c/1282c19:dd:d9:dd:c25:c25:94de:532c
462c19:dd:d9:dd:c25:c25:94de:532d/1282c19:dd:d9:dd:c25:c25:94de:532d
472c19:dd:d9:dd:c25:c25:94de:532e/1282c19:dd:d9:dd:c25:c25:94de:532e
482c19:dd:d9:dd:c25:c25:94de:532f/1282c19:dd:d9:dd:c25:c25:94de:532f
492c19:dd:d9:dd:c25:c25:94de:5330/1282c19:dd:d9:dd:c25:c25:94de:5330
502c19:dd:d9:dd:c25:c25:94de:5331/1282c19:dd:d9:dd:c25:c25:94de:5331
512c19:dd:d9:dd:c25:c25:94de:5332/1282c19:dd:d9:dd:c25:c25:94de:5332
522c19:dd:d9:dd:c25:c25:94de:5333/1282c19:dd:d9:dd:c25:c25:94de:5333
532c19:dd:d9:dd:c25:c25:94de:5334/1282c19:dd:d9:dd:c25:c25:94de:5334
542c19:dd:d9:dd:c25:c25:94de:5335/1282c19:dd:d9:dd:c25:c25:94de:5335
552c19:dd:d9:dd:c25:c25:94de:5336/1282c19:dd:d9:dd:c25:c25:94de:5336
562c19:dd:d9:dd:c25:c25:94de:5337/1282c19:dd:d9:dd:c25:c25:94de:5337
572c19:dd:d9:dd:c25:c25:94de:5338/1282c19:dd:d9:dd:c25:c25:94de:5338
582c19:dd:d9:dd:c25:c25:94de:5339/1282c19:dd:d9:dd:c25:c25:94de:5339
592c19:dd:d9:dd:c25:c25:94de:533a/1282c19:dd:d9:dd:c25:c25:94de:533a
602c19:dd:d9:dd:c25:c25:94de:533b/1282c19:dd:d9:dd:c25:c25:94de:533b
612c19:dd:d9:dd:c25:c25:94de:533c/1282c19:dd:d9:dd:c25:c25:94de:533c
622c19:dd:d9:dd:c25:c25:94de:533d/1282c19:dd:d9:dd:c25:c25:94de:533d
632c19:dd:d9:dd:c25:c25:94de:533e/1282c19:dd:d9:dd:c25:c25:94de:533e
642c19:dd:d9:dd:c25:c25:94de:533f/1282c19:dd:d9:dd:c25:c25:94de:533f
652c19:dd:d9:dd:c25:c25:94de:5340/1282c19:dd:d9:dd:c25:c25:94de:5340
662c19:dd:d9:dd:c25:c25:94de:5341/1282c19:dd:d9:dd:c25:c25:94de:5341
672c19:dd:d9:dd:c25:c25:94de:5342/1282c19:dd:d9:dd:c25:c25:94de:5342
682c19:dd:d9:dd:c25:c25:94de:5343/1282c19:dd:d9:dd:c25:c25:94de:5343
692c19:dd:d9:dd:c25:c25:94de:5344/1282c19:dd:d9:dd:c25:c25:94de:5344
702c19:dd:d9:dd:c25:c25:94de:5345/1282c19:dd:d9:dd:c25:c25:94de:5345
712c19:dd:d9:dd:c25:c25:94de:5346/1282c19:dd:d9:dd:c25:c25:94de:5346
722c19:dd:d9:dd:c25:c25:94de:5347/1282c19:dd:d9:dd:c25:c25:94de:5347
732c19:dd:d9:dd:c25:c25:94de:5348/1282c19:dd:d9:dd:c25:c25:94de:5348
742c19:dd:d9:dd:c25:c25:94de:5349/1282c19:dd:d9:dd:c25:c25:94de:5349
752c19:dd:d9:dd:c25:c25:94de:534a/1282c19:dd:d9:dd:c25:c25:94de:534a
762c19:dd:d9:dd:c25:c25:94de:534b/1282c19:dd:d9:dd:c25:c25:94de:534b
772c19:dd:d9:dd:c25:c25:94de:534c/1282c19:dd:d9:dd:c25:c25:94de:534c
782c19:dd:d9:dd:c25:c25:94de:534d/1282c19:dd:d9:dd:c25:c25:94de:534d
792c19:dd:d9:dd:c25:c25:94de:534e/1282c19:dd:d9:dd:c25:c25:94de:534e
802c19:dd:d9:dd:c25:c25:94de:534f/1282c19:dd:d9:dd:c25:c25:94de:534f
812c19:dd:d9:dd:c25:c25:94de:5350/1282c19:dd:d9:dd:c25:c25:94de:5350
822c19:dd:d9:dd:c25:c25:94de:5351/1282c19:dd:d9:dd:c25:c25:94de:5351
832c19:dd:d9:dd:c25:c25:94de:5352/1282c19:dd:d9:dd:c25:c25:94de:5352
842c19:dd:d9:dd:c25:c25:94de:5353/1282c19:dd:d9:dd:c25:c25:94de:5353
852c19:dd:d9:dd:c25:c25:94de:5354/1282c19:dd:d9:dd:c25:c25:94de:5354
862c19:dd:d9:dd:c25:c25:94de:5355/1282c19:dd:d9:dd:c25:c25:94de:5355
872c19:dd:d9:dd:c25:c25:94de:5356/1282c19:dd:d9:dd:c25:c25:94de:5356
882c19:dd:d9:dd:c25:c25:94de:5357/1282c19:dd:d9:dd:c25:c25:94de:5357
892c19:dd:d9:dd:c25:c25:94de:5358/1282c19:dd:d9:dd:c25:c25:94de:5358
902c19:dd:d9:dd:c25:c25:94de:5359/1282c19:dd:d9:dd:c25:c25:94de:5359
912c19:dd:d9:dd:c25:c25:94de:535a/1282c19:dd:d9:dd:c25:c25:94de:535a
922c19:dd:d9:dd:c25:c25:94de:535b/1282c19:dd:d9:dd:c25:c25:94de:535b
932c19:dd:d9:dd:c25:c25:94de:535c/1282c19:dd:d9:dd:c25:c25:94de:535c
942c19:dd:d9:dd:c25:c25:94de:535d/1282c19:dd:d9:dd:c25:c25:94de:535d
952c19:dd:d9:dd:c25:c25:94de:535e/1282c19:dd:d9:dd:c25:c25:94de:535e
962c19:dd:d9:dd:c25:c25:94de:535f/1282c19:dd:d9:dd:c25:c25:94de:535f
972c19:dd:d9:dd:c25:c25:94de:5360/1282c19:dd:d9:dd:c25:c25:94de:5360
982c19:dd:d9:dd:c25:c25:94de:5361/1282c19:dd:d9:dd:c25:c25:94de:5361
992c19:dd:d9:dd:c25:c25:94de:5362/1282c19:dd:d9:dd:c25:c25:94de:5362
1002c19:dd:d9:dd:c25:c25:94de:5363/1282c19:dd:d9:dd:c25:c25:94de:5363
1012c19:dd:d9:dd:c25:c25:94de:5364/1282c19:dd:d9:dd:c25:c25:94de:5364
1022c19:dd:d9:dd:c25:c25:94de:5365/1282c19:dd:d9:dd:c25:c25:94de:5365
1032c19:dd:d9:dd:c25:c25:94de:5366/1282c19:dd:d9:dd:c25:c25:94de:5366
1042c19:dd:d9:dd:c25:c25:94de:5367/1282c19:dd:d9:dd:c25:c25:94de:5367
1052c19:dd:d9:dd:c25:c25:94de:5368/1282c19:dd:d9:dd:c25:c25:94de:5368
1062c19:dd:d9:dd:c25:c25:94de:5369/1282c19:dd:d9:dd:c25:c25:94de:5369
1072c19:dd:d9:dd:c25:c25:94de:536a/1282c19:dd:d9:dd:c25:c25:94de:536a
1082c19:dd:d9:dd:c25:c25:94de:536b/1282c19:dd:d9:dd:c25:c25:94de:536b
1092c19:dd:d9:dd:c25:c25:94de:536c/1282c19:dd:d9:dd:c25:c25:94de:536c
1102c19:dd:d9:dd:c25:c25:94de:536d/1282c19:dd:d9:dd:c25:c25:94de:536d
1112c19:dd:d9:dd:c25:c25:94de:536e/1282c19:dd:d9:dd:c25:c25:94de:536e
1122c19:dd:d9:dd:c25:c25:94de:536f/1282c19:dd:d9:dd:c25:c25:94de:536f
1132c19:dd:d9:dd:c25:c25:94de:5370/1282c19:dd:d9:dd:c25:c25:94de:5370
1142c19:dd:d9:dd:c25:c25:94de:5371/1282c19:dd:d9:dd:c25:c25:94de:5371
1152c19:dd:d9:dd:c25:c25:94de:5372/1282c19:dd:d9:dd:c25:c25:94de:5372
1162c19:dd:d9:dd:c25:c25:94de:5373/1282c19:dd:d9:dd:c25:c25:94de:5373
1172c19:dd:d9:dd:c25:c25:94de:5374/1282c19:dd:d9:dd:c25:c25:94de:5374
1182c19:dd:d9:dd:c25:c25:94de:5375/1282c19:dd:d9:dd:c25:c25:94de:5375
1192c19:dd:d9:dd:c25:c25:94de:5376/1282c19:dd:d9:dd:c25:c25:94de:5376
1202c19:dd:d9:dd:c25:c25:94de:5377/1282c19:dd:d9:dd:c25:c25:94de:5377
1212c19:dd:d9:dd:c25:c25:94de:5378/1282c19:dd:d9:dd:c25:c25:94de:5378
1222c19:dd:d9:dd:c25:c25:94de:5379/1282c19:dd:d9:dd:c25:c25:94de:5379
1232c19:dd:d9:dd:c25:c25:94de:537a/1282c19:dd:d9:dd:c25:c25:94de:537a
1242c19:dd:d9:dd:c25:c25:94de:537b/1282c19:dd:d9:dd:c25:c25:94de:537b
1252c19:dd:d9:dd:c25:c25:94de:537c/1282c19:dd:d9:dd:c25:c25:94de:537c
1262c19:dd:d9:dd:c25:c25:94de:537d/1282c19:dd:d9:dd:c25:c25:94de:537d
1272c19:dd:d9:dd:c25:c25:94de:537e/1282c19:dd:d9:dd:c25:c25:94de:537e
1282c19:dd:d9:dd:c25:c25:94de:537f/1282c19:dd:d9:dd:c25:c25:94de:537f
1292c19:dd:d9:dd:c25:c25:94de:5380/1282c19:dd:d9:dd:c25:c25:94de:5380
1302c19:dd:d9:dd:c25:c25:94de:5381/1282c19:dd:d9:dd:c25:c25:94de:5381
1312c19:dd:d9:dd:c25:c25:94de:5382/1282c19:dd:d9:dd:c25:c25:94de:5382
1322c19:dd:d9:dd:c25:c25:94de:5383/1282c19:dd:d9:dd:c25:c25:94de:5383
1332c19:dd:d9:dd:c25:c25:94de:5384/1282c19:dd:d9:dd:c25:c25:94de:5384
1342c19:dd:d9:dd:c25:c25:94de:5385/1282c19:dd:d9:dd:c25:c25:94de:5385
1352c19:dd:d9:dd:c25:c25:94de:5386/1282c19:dd:d9:dd:c25:c25:94de:5386
1362c19:dd:d9:dd:c25:c25:94de:5387/1282c19:dd:d9:dd:c25:c25:94de:5387
1372c19:dd:d9:dd:c25:c25:94de:5388/1282c19:dd:d9:dd:c25:c25:94de:5388
1382c19:dd:d9:dd:c25:c25:94de:5389/1282c19:dd:d9:dd:c25:c25:94de:5389
1392c19:dd:d9:dd:c25:c25:94de:538a/1282c19:dd:d9:dd:c25:c25:94de:538a
1402c19:dd:d9:dd:c25:c25:94de:538b/1282c19:dd:d9:dd:c25:c25:94de:538b
1412c19:dd:d9:dd:c25:c25:94de:538c/1282c19:dd:d9:dd:c25:c25:94de:538c
1422c19:dd:d9:dd:c25:c25:94de:538d/1282c19:dd:d9:dd:c25:c25:94de:538d
1432c19:dd:d9:dd:c25:c25:94de:538e/1282c19:dd:d9:dd:c25:c25:94de:538e
1442c19:dd:d9:dd:c25:c25:94de:538f/1282c19:dd:d9:dd:c25:c25:94de:538f
1452c19:dd:d9:dd:c25:c25:94de:5390/1282c19:dd:d9:dd:c25:c25:94de:5390
1462c19:dd:d9:dd:c25:c25:94de:5391/1282c19:dd:d9:dd:c25:c25:94de:5391
1472c19:dd:d9:dd:c25:c25:94de:5392/1282c19:dd:d9:dd:c25:c25:94de:5392
1482c19:dd:d9:dd:c25:c25:94de:5393/1282c19:dd:d9:dd:c25:c25:94de:5393
1492c19:dd:d9:dd:c25:c25:94de:5394/1282c19:dd:d9:dd:c25:c25:94de:5394
1502c19:dd:d9:dd:c25:c25:94de:5395/1282c19:dd:d9:dd:c25:c25:94de:5395
1512c19:dd:d9:dd:c25:c25:94de:5396/1282c19:dd:d9:dd:c25:c25:94de:5396
1522c19:dd:d9:dd:c25:c25:94de:5397/1282c19:dd:d9:dd:c25:c25:94de:5397
1532c19:dd:d9:dd:c25:c25:94de:5398/1282c19:dd:d9:dd:c25:c25:94de:5398
1542c19:dd:d9:dd:c25:c25:94de:5399/1282c19:dd:d9:dd:c25:c25:94de:5399
1552c19:dd:d9:dd:c25:c25:94de:539a/1282c19:dd:d9:dd:c25:c25:94de:539a
1562c19:dd:d9:dd:c25:c25:94de:539b/1282c19:dd:d9:dd:c25:c25:94de:539b
1572c19:dd:d9:dd:c25:c25:94de:539c/1282c19:dd:d9:dd:c25:c25:94de:539c
1582c19:dd:d9:dd:c25:c25:94de:539d/1282c19:dd:d9:dd:c25:c25:94de:539d
1592c19:dd:d9:dd:c25:c25:94de:539e/1282c19:dd:d9:dd:c25:c25:94de:539e
1602c19:dd:d9:dd:c25:c25:94de:539f/1282c19:dd:d9:dd:c25:c25:94de:539f
1612c19:dd:d9:dd:c25:c25:94de:53a0/1282c19:dd:d9:dd:c25:c25:94de:53a0
1622c19:dd:d9:dd:c25:c25:94de:53a1/1282c19:dd:d9:dd:c25:c25:94de:53a1
1632c19:dd:d9:dd:c25:c25:94de:53a2/1282c19:dd:d9:dd:c25:c25:94de:53a2
1642c19:dd:d9:dd:c25:c25:94de:53a3/1282c19:dd:d9:dd:c25:c25:94de:53a3
1652c19:dd:d9:dd:c25:c25:94de:53a4/1282c19:dd:d9:dd:c25:c25:94de:53a4
1662c19:dd:d9:dd:c25:c25:94de:53a5/1282c19:dd:d9:dd:c25:c25:94de:53a5
1672c19:dd:d9:dd:c25:c25:94de:53a6/1282c19:dd:d9:dd:c25:c25:94de:53a6
1682c19:dd:d9:dd:c25:c25:94de:53a7/1282c19:dd:d9:dd:c25:c25:94de:53a7
1692c19:dd:d9:dd:c25:c25:94de:53a8/1282c19:dd:d9:dd:c25:c25:94de:53a8
1702c19:dd:d9:dd:c25:c25:94de:53a9/1282c19:dd:d9:dd:c25:c25:94de:53a9
1712c19:dd:d9:dd:c25:c25:94de:53aa/1282c19:dd:d9:dd:c25:c25:94de:53aa
1722c19:dd:d9:dd:c25:c25:94de:53ab/1282c19:dd:d9:dd:c25:c25:94de:53ab
1732c19:dd:d9:dd:c25:c25:94de:53ac/1282c19:dd:d9:dd:c25:c25:94de:53ac
1742c19:dd:d9:dd:c25:c25:94de:53ad/1282c19:dd:d9:dd:c25:c25:94de:53ad
1752c19:dd:d9:dd:c25:c25:94de:53ae/1282c19:dd:d9:dd:c25:c25:94de:53ae
1762c19:dd:d9:dd:c25:c25:94de:53af/1282c19:dd:d9:dd:c25:c25:94de:53af
1772c19:dd:d9:dd:c25:c25:94de:53b0/1282c19:dd:d9:dd:c25:c25:94de:53b0
1782c19:dd:d9:dd:c25:c25:94de:53b1/1282c19:dd:d9:dd:c25:c25:94de:53b1
1792c19:dd:d9:dd:c25:c25:94de:53b2/1282c19:dd:d9:dd:c25:c25:94de:53b2
1802c19:dd:d9:dd:c25:c25:94de:53b3/1282c19:dd:d9:dd:c25:c25:94de:53b3
1812c19:dd:d9:dd:c25:c25:94de:53b4/1282c19:dd:d9:dd:c25:c25:94de:53b4
1822c19:dd:d9:dd:c25:c25:94de:53b5/1282c19:dd:d9:dd:c25:c25:94de:53b5
1832c19:dd:d9:dd:c25:c25:94de:53b6/1282c19:dd:d9:dd:c25:c25:94de:53b6
1842c19:dd:d9:dd:c25:c25:94de:53b7/1282c19:dd:d9:dd:c25:c25:94de:53b7
1852c19:dd:d9:dd:c25:c25:94de:53b8/1282c19:dd:d9:dd:c25:c25:94de:53b8
1862c19:dd:d9:dd:c25:c25:94de:53b9/1282c19:dd:d9:dd:c25:c25:94de:53b9
1872c19:dd:d9:dd:c25:c25:94de:53ba/1282c19:dd:d9:dd:c25:c25:94de:53ba
1882c19:dd:d9:dd:c25:c25:94de:53bb/1282c19:dd:d9:dd:c25:c25:94de:53bb
1892c19:dd:d9:dd:c25:c25:94de:53bc/1282c19:dd:d9:dd:c25:c25:94de:53bc
1902c19:dd:d9:dd:c25:c25:94de:53bd/1282c19:dd:d9:dd:c25:c25:94de:53bd
1912c19:dd:d9:dd:c25:c25:94de:53be/1282c19:dd:d9:dd:c25:c25:94de:53be
1922c19:dd:d9:dd:c25:c25:94de:53bf/1282c19:dd:d9:dd:c25:c25:94de:53bf
1932c19:dd:d9:dd:c25:c25:94de:53c0/1282c19:dd:d9:dd:c25:c25:94de:53c0
1942c19:dd:d9:dd:c25:c25:94de:53c1/1282c19:dd:d9:dd:c25:c25:94de:53c1
1952c19:dd:d9:dd:c25:c25:94de:53c2/1282c19:dd:d9:dd:c25:c25:94de:53c2
1962c19:dd:d9:dd:c25:c25:94de:53c3/1282c19:dd:d9:dd:c25:c25:94de:53c3
1972c19:dd:d9:dd:c25:c25:94de:53c4/1282c19:dd:d9:dd:c25:c25:94de:53c4
1982c19:dd:d9:dd:c25:c25:94de:53c5/1282c19:dd:d9:dd:c25:c25:94de:53c5
1992c19:dd:d9:dd:c25:c25:94de:53c6/1282c19:dd:d9:dd:c25:c25:94de:53c6
2002c19:dd:d9:dd:c25:c25:94de:53c7/1282c19:dd:d9:dd:c25:c25:94de:53c7
2012c19:dd:d9:dd:c25:c25:94de:53c8/1282c19:dd:d9:dd:c25:c25:94de:53c8
2022c19:dd:d9:dd:c25:c25:94de:53c9/1282c19:dd:d9:dd:c25:c25:94de:53c9
2032c19:dd:d9:dd:c25:c25:94de:53ca/1282c19:dd:d9:dd:c25:c25:94de:53ca
2042c19:dd:d9:dd:c25:c25:94de:53cb/1282c19:dd:d9:dd:c25:c25:94de:53cb
2052c19:dd:d9:dd:c25:c25:94de:53cc/1282c19:dd:d9:dd:c25:c25:94de:53cc
2062c19:dd:d9:dd:c25:c25:94de:53cd/1282c19:dd:d9:dd:c25:c25:94de:53cd
2072c19:dd:d9:dd:c25:c25:94de:53ce/1282c19:dd:d9:dd:c25:c25:94de:53ce
2082c19:dd:d9:dd:c25:c25:94de:53cf/1282c19:dd:d9:dd:c25:c25:94de:53cf
2092c19:dd:d9:dd:c25:c25:94de:53d0/1282c19:dd:d9:dd:c25:c25:94de:53d0
2102c19:dd:d9:dd:c25:c25:94de:53d1/1282c19:dd:d9:dd:c25:c25:94de:53d1
2112c19:dd:d9:dd:c25:c25:94de:53d2/1282c19:dd:d9:dd:c25:c25:94de:53d2
2122c19:dd:d9:dd:c25:c25:94de:53d3/1282c19:dd:d9:dd:c25:c25:94de:53d3
2132c19:dd:d9:dd:c25:c25:94de:53d4/1282c19:dd:d9:dd:c25:c25:94de:53d4
2142c19:dd:d9:dd:c25:c25:94de:53d5/1282c19:dd:d9:dd:c25:c25:94de:53d5
2152c19:dd:d9:dd:c25:c25:94de:53d6/1282c19:dd:d9:dd:c25:c25:94de:53d6
2162c19:dd:d9:dd:c25:c25:94de:53d7/1282c19:dd:d9:dd:c25:c25:94de:53d7
2172c19:dd:d9:dd:c25:c25:94de:53d8/1282c19:dd:d9:dd:c25:c25:94de:53d8
2182c19:dd:d9:dd:c25:c25:94de:53d9/1282c19:dd:d9:dd:c25:c25:94de:53d9
2192c19:dd:d9:dd:c25:c25:94de:53da/1282c19:dd:d9:dd:c25:c25:94de:53da
2202c19:dd:d9:dd:c25:c25:94de:53db/1282c19:dd:d9:dd:c25:c25:94de:53db
2212c19:dd:d9:dd:c25:c25:94de:53dc/1282c19:dd:d9:dd:c25:c25:94de:53dc
2222c19:dd:d9:dd:c25:c25:94de:53dd/1282c19:dd:d9:dd:c25:c25:94de:53dd
2232c19:dd:d9:dd:c25:c25:94de:53de/1282c19:dd:d9:dd:c25:c25:94de:53de
2242c19:dd:d9:dd:c25:c25:94de:53df/1282c19:dd:d9:dd:c25:c25:94de:53df
2252c19:dd:d9:dd:c25:c25:94de:53e0/1282c19:dd:d9:dd:c25:c25:94de:53e0
2262c19:dd:d9:dd:c25:c25:94de:53e1/1282c19:dd:d9:dd:c25:c25:94de:53e1
2272c19:dd:d9:dd:c25:c25:94de:53e2/1282c19:dd:d9:dd:c25:c25:94de:53e2
2282c19:dd:d9:dd:c25:c25:94de:53e3/1282c19:dd:d9:dd:c25:c25:94de:53e3
2292c19:dd:d9:dd:c25:c25:94de:53e4/1282c19:dd:d9:dd:c25:c25:94de:53e4
2302c19:dd:d9:dd:c25:c25:94de:53e5/1282c19:dd:d9:dd:c25:c25:94de:53e5
2312c19:dd:d9:dd:c25:c25:94de:53e6/1282c19:dd:d9:dd:c25:c25:94de:53e6
2322c19:dd:d9:dd:c25:c25:94de:53e7/1282c19:dd:d9:dd:c25:c25:94de:53e7
2332c19:dd:d9:dd:c25:c25:94de:53e8/1282c19:dd:d9:dd:c25:c25:94de:53e8
2342c19:dd:d9:dd:c25:c25:94de:53e9/1282c19:dd:d9:dd:c25:c25:94de:53e9
2352c19:dd:d9:dd:c25:c25:94de:53ea/1282c19:dd:d9:dd:c25:c25:94de:53ea
2362c19:dd:d9:dd:c25:c25:94de:53eb/1282c19:dd:d9:dd:c25:c25:94de:53eb
2372c19:dd:d9:dd:c25:c25:94de:53ec/1282c19:dd:d9:dd:c25:c25:94de:53ec
2382c19:dd:d9:dd:c25:c25:94de:53ed/1282c19:dd:d9:dd:c25:c25:94de:53ed
2392c19:dd:d9:dd:c25:c25:94de:53ee/1282c19:dd:d9:dd:c25:c25:94de:53ee
2402c19:dd:d9:dd:c25:c25:94de:53ef/1282c19:dd:d9:dd:c25:c25:94de:53ef
2412c19:dd:d9:dd:c25:c25:94de:53f0/1282c19:dd:d9:dd:c25:c25:94de:53f0
2422c19:dd:d9:dd:c25:c25:94de:53f1/1282c19:dd:d9:dd:c25:c25:94de:53f1
2432c19:dd:d9:dd:c25:c25:94de:53f2/1282c19:dd:d9:dd:c25:c25:94de:53f2
2442c19:dd:d9:dd:c25:c25:94de:53f3/1282c19:dd:d9:dd:c25:c25:94de:53f3
2452c19:dd:d9:dd:c25:c25:94de:53f4/1282c19:dd:d9:dd:c25:c25:94de:53f4
2462c19:dd:d9:dd:c25:c25:94de:53f5/1282c19:dd:d9:dd:c25:c25:94de:53f5
2472c19:dd:d9:dd:c25:c25:94de:53f6/1282c19:dd:d9:dd:c25:c25:94de:53f6
2482c19:dd:d9:dd:c25:c25:94de:53f7/1282c19:dd:d9:dd:c25:c25:94de:53f7
2492c19:dd:d9:dd:c25:c25:94de:53f8/1282c19:dd:d9:dd:c25:c25:94de:53f8
2502c19:dd:d9:dd:c25:c25:94de:53f9/1282c19:dd:d9:dd:c25:c25:94de:53f9
2512c19:dd:d9:dd:c25:c25:94de:53fa/1282c19:dd:d9:dd:c25:c25:94de:53fa
2522c19:dd:d9:dd:c25:c25:94de:53fb/1282c19:dd:d9:dd:c25:c25:94de:53fb
2532c19:dd:d9:dd:c25:c25:94de:53fc/1282c19:dd:d9:dd:c25:c25:94de:53fc
2542c19:dd:d9:dd:c25:c25:94de:53fd/1282c19:dd:d9:dd:c25:c25:94de:53fd
2552c19:dd:d9:dd:c25:c25:94de:53fe/1282c19:dd:d9:dd:c25:c25:94de:53fe
2562c19:dd:d9:dd:c25:c25:94de:53ff/1282c19:dd:d9:dd:c25:c25:94de:53ff

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.