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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:8300/120
First address
2c19:dd:d9:dd:c25:c25:94de:8300
Last address
2c19:dd:d9:dd:c25:c25:94de:83ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:8300
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.8.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:8300/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:8300/1282c19:dd:d9:dd:c25:c25:94de:8300
22c19:dd:d9:dd:c25:c25:94de:8301/1282c19:dd:d9:dd:c25:c25:94de:8301
32c19:dd:d9:dd:c25:c25:94de:8302/1282c19:dd:d9:dd:c25:c25:94de:8302
42c19:dd:d9:dd:c25:c25:94de:8303/1282c19:dd:d9:dd:c25:c25:94de:8303
52c19:dd:d9:dd:c25:c25:94de:8304/1282c19:dd:d9:dd:c25:c25:94de:8304
62c19:dd:d9:dd:c25:c25:94de:8305/1282c19:dd:d9:dd:c25:c25:94de:8305
72c19:dd:d9:dd:c25:c25:94de:8306/1282c19:dd:d9:dd:c25:c25:94de:8306
82c19:dd:d9:dd:c25:c25:94de:8307/1282c19:dd:d9:dd:c25:c25:94de:8307
92c19:dd:d9:dd:c25:c25:94de:8308/1282c19:dd:d9:dd:c25:c25:94de:8308
102c19:dd:d9:dd:c25:c25:94de:8309/1282c19:dd:d9:dd:c25:c25:94de:8309
112c19:dd:d9:dd:c25:c25:94de:830a/1282c19:dd:d9:dd:c25:c25:94de:830a
122c19:dd:d9:dd:c25:c25:94de:830b/1282c19:dd:d9:dd:c25:c25:94de:830b
132c19:dd:d9:dd:c25:c25:94de:830c/1282c19:dd:d9:dd:c25:c25:94de:830c
142c19:dd:d9:dd:c25:c25:94de:830d/1282c19:dd:d9:dd:c25:c25:94de:830d
152c19:dd:d9:dd:c25:c25:94de:830e/1282c19:dd:d9:dd:c25:c25:94de:830e
162c19:dd:d9:dd:c25:c25:94de:830f/1282c19:dd:d9:dd:c25:c25:94de:830f
172c19:dd:d9:dd:c25:c25:94de:8310/1282c19:dd:d9:dd:c25:c25:94de:8310
182c19:dd:d9:dd:c25:c25:94de:8311/1282c19:dd:d9:dd:c25:c25:94de:8311
192c19:dd:d9:dd:c25:c25:94de:8312/1282c19:dd:d9:dd:c25:c25:94de:8312
202c19:dd:d9:dd:c25:c25:94de:8313/1282c19:dd:d9:dd:c25:c25:94de:8313
212c19:dd:d9:dd:c25:c25:94de:8314/1282c19:dd:d9:dd:c25:c25:94de:8314
222c19:dd:d9:dd:c25:c25:94de:8315/1282c19:dd:d9:dd:c25:c25:94de:8315
232c19:dd:d9:dd:c25:c25:94de:8316/1282c19:dd:d9:dd:c25:c25:94de:8316
242c19:dd:d9:dd:c25:c25:94de:8317/1282c19:dd:d9:dd:c25:c25:94de:8317
252c19:dd:d9:dd:c25:c25:94de:8318/1282c19:dd:d9:dd:c25:c25:94de:8318
262c19:dd:d9:dd:c25:c25:94de:8319/1282c19:dd:d9:dd:c25:c25:94de:8319
272c19:dd:d9:dd:c25:c25:94de:831a/1282c19:dd:d9:dd:c25:c25:94de:831a
282c19:dd:d9:dd:c25:c25:94de:831b/1282c19:dd:d9:dd:c25:c25:94de:831b
292c19:dd:d9:dd:c25:c25:94de:831c/1282c19:dd:d9:dd:c25:c25:94de:831c
302c19:dd:d9:dd:c25:c25:94de:831d/1282c19:dd:d9:dd:c25:c25:94de:831d
312c19:dd:d9:dd:c25:c25:94de:831e/1282c19:dd:d9:dd:c25:c25:94de:831e
322c19:dd:d9:dd:c25:c25:94de:831f/1282c19:dd:d9:dd:c25:c25:94de:831f
332c19:dd:d9:dd:c25:c25:94de:8320/1282c19:dd:d9:dd:c25:c25:94de:8320
342c19:dd:d9:dd:c25:c25:94de:8321/1282c19:dd:d9:dd:c25:c25:94de:8321
352c19:dd:d9:dd:c25:c25:94de:8322/1282c19:dd:d9:dd:c25:c25:94de:8322
362c19:dd:d9:dd:c25:c25:94de:8323/1282c19:dd:d9:dd:c25:c25:94de:8323
372c19:dd:d9:dd:c25:c25:94de:8324/1282c19:dd:d9:dd:c25:c25:94de:8324
382c19:dd:d9:dd:c25:c25:94de:8325/1282c19:dd:d9:dd:c25:c25:94de:8325
392c19:dd:d9:dd:c25:c25:94de:8326/1282c19:dd:d9:dd:c25:c25:94de:8326
402c19:dd:d9:dd:c25:c25:94de:8327/1282c19:dd:d9:dd:c25:c25:94de:8327
412c19:dd:d9:dd:c25:c25:94de:8328/1282c19:dd:d9:dd:c25:c25:94de:8328
422c19:dd:d9:dd:c25:c25:94de:8329/1282c19:dd:d9:dd:c25:c25:94de:8329
432c19:dd:d9:dd:c25:c25:94de:832a/1282c19:dd:d9:dd:c25:c25:94de:832a
442c19:dd:d9:dd:c25:c25:94de:832b/1282c19:dd:d9:dd:c25:c25:94de:832b
452c19:dd:d9:dd:c25:c25:94de:832c/1282c19:dd:d9:dd:c25:c25:94de:832c
462c19:dd:d9:dd:c25:c25:94de:832d/1282c19:dd:d9:dd:c25:c25:94de:832d
472c19:dd:d9:dd:c25:c25:94de:832e/1282c19:dd:d9:dd:c25:c25:94de:832e
482c19:dd:d9:dd:c25:c25:94de:832f/1282c19:dd:d9:dd:c25:c25:94de:832f
492c19:dd:d9:dd:c25:c25:94de:8330/1282c19:dd:d9:dd:c25:c25:94de:8330
502c19:dd:d9:dd:c25:c25:94de:8331/1282c19:dd:d9:dd:c25:c25:94de:8331
512c19:dd:d9:dd:c25:c25:94de:8332/1282c19:dd:d9:dd:c25:c25:94de:8332
522c19:dd:d9:dd:c25:c25:94de:8333/1282c19:dd:d9:dd:c25:c25:94de:8333
532c19:dd:d9:dd:c25:c25:94de:8334/1282c19:dd:d9:dd:c25:c25:94de:8334
542c19:dd:d9:dd:c25:c25:94de:8335/1282c19:dd:d9:dd:c25:c25:94de:8335
552c19:dd:d9:dd:c25:c25:94de:8336/1282c19:dd:d9:dd:c25:c25:94de:8336
562c19:dd:d9:dd:c25:c25:94de:8337/1282c19:dd:d9:dd:c25:c25:94de:8337
572c19:dd:d9:dd:c25:c25:94de:8338/1282c19:dd:d9:dd:c25:c25:94de:8338
582c19:dd:d9:dd:c25:c25:94de:8339/1282c19:dd:d9:dd:c25:c25:94de:8339
592c19:dd:d9:dd:c25:c25:94de:833a/1282c19:dd:d9:dd:c25:c25:94de:833a
602c19:dd:d9:dd:c25:c25:94de:833b/1282c19:dd:d9:dd:c25:c25:94de:833b
612c19:dd:d9:dd:c25:c25:94de:833c/1282c19:dd:d9:dd:c25:c25:94de:833c
622c19:dd:d9:dd:c25:c25:94de:833d/1282c19:dd:d9:dd:c25:c25:94de:833d
632c19:dd:d9:dd:c25:c25:94de:833e/1282c19:dd:d9:dd:c25:c25:94de:833e
642c19:dd:d9:dd:c25:c25:94de:833f/1282c19:dd:d9:dd:c25:c25:94de:833f
652c19:dd:d9:dd:c25:c25:94de:8340/1282c19:dd:d9:dd:c25:c25:94de:8340
662c19:dd:d9:dd:c25:c25:94de:8341/1282c19:dd:d9:dd:c25:c25:94de:8341
672c19:dd:d9:dd:c25:c25:94de:8342/1282c19:dd:d9:dd:c25:c25:94de:8342
682c19:dd:d9:dd:c25:c25:94de:8343/1282c19:dd:d9:dd:c25:c25:94de:8343
692c19:dd:d9:dd:c25:c25:94de:8344/1282c19:dd:d9:dd:c25:c25:94de:8344
702c19:dd:d9:dd:c25:c25:94de:8345/1282c19:dd:d9:dd:c25:c25:94de:8345
712c19:dd:d9:dd:c25:c25:94de:8346/1282c19:dd:d9:dd:c25:c25:94de:8346
722c19:dd:d9:dd:c25:c25:94de:8347/1282c19:dd:d9:dd:c25:c25:94de:8347
732c19:dd:d9:dd:c25:c25:94de:8348/1282c19:dd:d9:dd:c25:c25:94de:8348
742c19:dd:d9:dd:c25:c25:94de:8349/1282c19:dd:d9:dd:c25:c25:94de:8349
752c19:dd:d9:dd:c25:c25:94de:834a/1282c19:dd:d9:dd:c25:c25:94de:834a
762c19:dd:d9:dd:c25:c25:94de:834b/1282c19:dd:d9:dd:c25:c25:94de:834b
772c19:dd:d9:dd:c25:c25:94de:834c/1282c19:dd:d9:dd:c25:c25:94de:834c
782c19:dd:d9:dd:c25:c25:94de:834d/1282c19:dd:d9:dd:c25:c25:94de:834d
792c19:dd:d9:dd:c25:c25:94de:834e/1282c19:dd:d9:dd:c25:c25:94de:834e
802c19:dd:d9:dd:c25:c25:94de:834f/1282c19:dd:d9:dd:c25:c25:94de:834f
812c19:dd:d9:dd:c25:c25:94de:8350/1282c19:dd:d9:dd:c25:c25:94de:8350
822c19:dd:d9:dd:c25:c25:94de:8351/1282c19:dd:d9:dd:c25:c25:94de:8351
832c19:dd:d9:dd:c25:c25:94de:8352/1282c19:dd:d9:dd:c25:c25:94de:8352
842c19:dd:d9:dd:c25:c25:94de:8353/1282c19:dd:d9:dd:c25:c25:94de:8353
852c19:dd:d9:dd:c25:c25:94de:8354/1282c19:dd:d9:dd:c25:c25:94de:8354
862c19:dd:d9:dd:c25:c25:94de:8355/1282c19:dd:d9:dd:c25:c25:94de:8355
872c19:dd:d9:dd:c25:c25:94de:8356/1282c19:dd:d9:dd:c25:c25:94de:8356
882c19:dd:d9:dd:c25:c25:94de:8357/1282c19:dd:d9:dd:c25:c25:94de:8357
892c19:dd:d9:dd:c25:c25:94de:8358/1282c19:dd:d9:dd:c25:c25:94de:8358
902c19:dd:d9:dd:c25:c25:94de:8359/1282c19:dd:d9:dd:c25:c25:94de:8359
912c19:dd:d9:dd:c25:c25:94de:835a/1282c19:dd:d9:dd:c25:c25:94de:835a
922c19:dd:d9:dd:c25:c25:94de:835b/1282c19:dd:d9:dd:c25:c25:94de:835b
932c19:dd:d9:dd:c25:c25:94de:835c/1282c19:dd:d9:dd:c25:c25:94de:835c
942c19:dd:d9:dd:c25:c25:94de:835d/1282c19:dd:d9:dd:c25:c25:94de:835d
952c19:dd:d9:dd:c25:c25:94de:835e/1282c19:dd:d9:dd:c25:c25:94de:835e
962c19:dd:d9:dd:c25:c25:94de:835f/1282c19:dd:d9:dd:c25:c25:94de:835f
972c19:dd:d9:dd:c25:c25:94de:8360/1282c19:dd:d9:dd:c25:c25:94de:8360
982c19:dd:d9:dd:c25:c25:94de:8361/1282c19:dd:d9:dd:c25:c25:94de:8361
992c19:dd:d9:dd:c25:c25:94de:8362/1282c19:dd:d9:dd:c25:c25:94de:8362
1002c19:dd:d9:dd:c25:c25:94de:8363/1282c19:dd:d9:dd:c25:c25:94de:8363
1012c19:dd:d9:dd:c25:c25:94de:8364/1282c19:dd:d9:dd:c25:c25:94de:8364
1022c19:dd:d9:dd:c25:c25:94de:8365/1282c19:dd:d9:dd:c25:c25:94de:8365
1032c19:dd:d9:dd:c25:c25:94de:8366/1282c19:dd:d9:dd:c25:c25:94de:8366
1042c19:dd:d9:dd:c25:c25:94de:8367/1282c19:dd:d9:dd:c25:c25:94de:8367
1052c19:dd:d9:dd:c25:c25:94de:8368/1282c19:dd:d9:dd:c25:c25:94de:8368
1062c19:dd:d9:dd:c25:c25:94de:8369/1282c19:dd:d9:dd:c25:c25:94de:8369
1072c19:dd:d9:dd:c25:c25:94de:836a/1282c19:dd:d9:dd:c25:c25:94de:836a
1082c19:dd:d9:dd:c25:c25:94de:836b/1282c19:dd:d9:dd:c25:c25:94de:836b
1092c19:dd:d9:dd:c25:c25:94de:836c/1282c19:dd:d9:dd:c25:c25:94de:836c
1102c19:dd:d9:dd:c25:c25:94de:836d/1282c19:dd:d9:dd:c25:c25:94de:836d
1112c19:dd:d9:dd:c25:c25:94de:836e/1282c19:dd:d9:dd:c25:c25:94de:836e
1122c19:dd:d9:dd:c25:c25:94de:836f/1282c19:dd:d9:dd:c25:c25:94de:836f
1132c19:dd:d9:dd:c25:c25:94de:8370/1282c19:dd:d9:dd:c25:c25:94de:8370
1142c19:dd:d9:dd:c25:c25:94de:8371/1282c19:dd:d9:dd:c25:c25:94de:8371
1152c19:dd:d9:dd:c25:c25:94de:8372/1282c19:dd:d9:dd:c25:c25:94de:8372
1162c19:dd:d9:dd:c25:c25:94de:8373/1282c19:dd:d9:dd:c25:c25:94de:8373
1172c19:dd:d9:dd:c25:c25:94de:8374/1282c19:dd:d9:dd:c25:c25:94de:8374
1182c19:dd:d9:dd:c25:c25:94de:8375/1282c19:dd:d9:dd:c25:c25:94de:8375
1192c19:dd:d9:dd:c25:c25:94de:8376/1282c19:dd:d9:dd:c25:c25:94de:8376
1202c19:dd:d9:dd:c25:c25:94de:8377/1282c19:dd:d9:dd:c25:c25:94de:8377
1212c19:dd:d9:dd:c25:c25:94de:8378/1282c19:dd:d9:dd:c25:c25:94de:8378
1222c19:dd:d9:dd:c25:c25:94de:8379/1282c19:dd:d9:dd:c25:c25:94de:8379
1232c19:dd:d9:dd:c25:c25:94de:837a/1282c19:dd:d9:dd:c25:c25:94de:837a
1242c19:dd:d9:dd:c25:c25:94de:837b/1282c19:dd:d9:dd:c25:c25:94de:837b
1252c19:dd:d9:dd:c25:c25:94de:837c/1282c19:dd:d9:dd:c25:c25:94de:837c
1262c19:dd:d9:dd:c25:c25:94de:837d/1282c19:dd:d9:dd:c25:c25:94de:837d
1272c19:dd:d9:dd:c25:c25:94de:837e/1282c19:dd:d9:dd:c25:c25:94de:837e
1282c19:dd:d9:dd:c25:c25:94de:837f/1282c19:dd:d9:dd:c25:c25:94de:837f
1292c19:dd:d9:dd:c25:c25:94de:8380/1282c19:dd:d9:dd:c25:c25:94de:8380
1302c19:dd:d9:dd:c25:c25:94de:8381/1282c19:dd:d9:dd:c25:c25:94de:8381
1312c19:dd:d9:dd:c25:c25:94de:8382/1282c19:dd:d9:dd:c25:c25:94de:8382
1322c19:dd:d9:dd:c25:c25:94de:8383/1282c19:dd:d9:dd:c25:c25:94de:8383
1332c19:dd:d9:dd:c25:c25:94de:8384/1282c19:dd:d9:dd:c25:c25:94de:8384
1342c19:dd:d9:dd:c25:c25:94de:8385/1282c19:dd:d9:dd:c25:c25:94de:8385
1352c19:dd:d9:dd:c25:c25:94de:8386/1282c19:dd:d9:dd:c25:c25:94de:8386
1362c19:dd:d9:dd:c25:c25:94de:8387/1282c19:dd:d9:dd:c25:c25:94de:8387
1372c19:dd:d9:dd:c25:c25:94de:8388/1282c19:dd:d9:dd:c25:c25:94de:8388
1382c19:dd:d9:dd:c25:c25:94de:8389/1282c19:dd:d9:dd:c25:c25:94de:8389
1392c19:dd:d9:dd:c25:c25:94de:838a/1282c19:dd:d9:dd:c25:c25:94de:838a
1402c19:dd:d9:dd:c25:c25:94de:838b/1282c19:dd:d9:dd:c25:c25:94de:838b
1412c19:dd:d9:dd:c25:c25:94de:838c/1282c19:dd:d9:dd:c25:c25:94de:838c
1422c19:dd:d9:dd:c25:c25:94de:838d/1282c19:dd:d9:dd:c25:c25:94de:838d
1432c19:dd:d9:dd:c25:c25:94de:838e/1282c19:dd:d9:dd:c25:c25:94de:838e
1442c19:dd:d9:dd:c25:c25:94de:838f/1282c19:dd:d9:dd:c25:c25:94de:838f
1452c19:dd:d9:dd:c25:c25:94de:8390/1282c19:dd:d9:dd:c25:c25:94de:8390
1462c19:dd:d9:dd:c25:c25:94de:8391/1282c19:dd:d9:dd:c25:c25:94de:8391
1472c19:dd:d9:dd:c25:c25:94de:8392/1282c19:dd:d9:dd:c25:c25:94de:8392
1482c19:dd:d9:dd:c25:c25:94de:8393/1282c19:dd:d9:dd:c25:c25:94de:8393
1492c19:dd:d9:dd:c25:c25:94de:8394/1282c19:dd:d9:dd:c25:c25:94de:8394
1502c19:dd:d9:dd:c25:c25:94de:8395/1282c19:dd:d9:dd:c25:c25:94de:8395
1512c19:dd:d9:dd:c25:c25:94de:8396/1282c19:dd:d9:dd:c25:c25:94de:8396
1522c19:dd:d9:dd:c25:c25:94de:8397/1282c19:dd:d9:dd:c25:c25:94de:8397
1532c19:dd:d9:dd:c25:c25:94de:8398/1282c19:dd:d9:dd:c25:c25:94de:8398
1542c19:dd:d9:dd:c25:c25:94de:8399/1282c19:dd:d9:dd:c25:c25:94de:8399
1552c19:dd:d9:dd:c25:c25:94de:839a/1282c19:dd:d9:dd:c25:c25:94de:839a
1562c19:dd:d9:dd:c25:c25:94de:839b/1282c19:dd:d9:dd:c25:c25:94de:839b
1572c19:dd:d9:dd:c25:c25:94de:839c/1282c19:dd:d9:dd:c25:c25:94de:839c
1582c19:dd:d9:dd:c25:c25:94de:839d/1282c19:dd:d9:dd:c25:c25:94de:839d
1592c19:dd:d9:dd:c25:c25:94de:839e/1282c19:dd:d9:dd:c25:c25:94de:839e
1602c19:dd:d9:dd:c25:c25:94de:839f/1282c19:dd:d9:dd:c25:c25:94de:839f
1612c19:dd:d9:dd:c25:c25:94de:83a0/1282c19:dd:d9:dd:c25:c25:94de:83a0
1622c19:dd:d9:dd:c25:c25:94de:83a1/1282c19:dd:d9:dd:c25:c25:94de:83a1
1632c19:dd:d9:dd:c25:c25:94de:83a2/1282c19:dd:d9:dd:c25:c25:94de:83a2
1642c19:dd:d9:dd:c25:c25:94de:83a3/1282c19:dd:d9:dd:c25:c25:94de:83a3
1652c19:dd:d9:dd:c25:c25:94de:83a4/1282c19:dd:d9:dd:c25:c25:94de:83a4
1662c19:dd:d9:dd:c25:c25:94de:83a5/1282c19:dd:d9:dd:c25:c25:94de:83a5
1672c19:dd:d9:dd:c25:c25:94de:83a6/1282c19:dd:d9:dd:c25:c25:94de:83a6
1682c19:dd:d9:dd:c25:c25:94de:83a7/1282c19:dd:d9:dd:c25:c25:94de:83a7
1692c19:dd:d9:dd:c25:c25:94de:83a8/1282c19:dd:d9:dd:c25:c25:94de:83a8
1702c19:dd:d9:dd:c25:c25:94de:83a9/1282c19:dd:d9:dd:c25:c25:94de:83a9
1712c19:dd:d9:dd:c25:c25:94de:83aa/1282c19:dd:d9:dd:c25:c25:94de:83aa
1722c19:dd:d9:dd:c25:c25:94de:83ab/1282c19:dd:d9:dd:c25:c25:94de:83ab
1732c19:dd:d9:dd:c25:c25:94de:83ac/1282c19:dd:d9:dd:c25:c25:94de:83ac
1742c19:dd:d9:dd:c25:c25:94de:83ad/1282c19:dd:d9:dd:c25:c25:94de:83ad
1752c19:dd:d9:dd:c25:c25:94de:83ae/1282c19:dd:d9:dd:c25:c25:94de:83ae
1762c19:dd:d9:dd:c25:c25:94de:83af/1282c19:dd:d9:dd:c25:c25:94de:83af
1772c19:dd:d9:dd:c25:c25:94de:83b0/1282c19:dd:d9:dd:c25:c25:94de:83b0
1782c19:dd:d9:dd:c25:c25:94de:83b1/1282c19:dd:d9:dd:c25:c25:94de:83b1
1792c19:dd:d9:dd:c25:c25:94de:83b2/1282c19:dd:d9:dd:c25:c25:94de:83b2
1802c19:dd:d9:dd:c25:c25:94de:83b3/1282c19:dd:d9:dd:c25:c25:94de:83b3
1812c19:dd:d9:dd:c25:c25:94de:83b4/1282c19:dd:d9:dd:c25:c25:94de:83b4
1822c19:dd:d9:dd:c25:c25:94de:83b5/1282c19:dd:d9:dd:c25:c25:94de:83b5
1832c19:dd:d9:dd:c25:c25:94de:83b6/1282c19:dd:d9:dd:c25:c25:94de:83b6
1842c19:dd:d9:dd:c25:c25:94de:83b7/1282c19:dd:d9:dd:c25:c25:94de:83b7
1852c19:dd:d9:dd:c25:c25:94de:83b8/1282c19:dd:d9:dd:c25:c25:94de:83b8
1862c19:dd:d9:dd:c25:c25:94de:83b9/1282c19:dd:d9:dd:c25:c25:94de:83b9
1872c19:dd:d9:dd:c25:c25:94de:83ba/1282c19:dd:d9:dd:c25:c25:94de:83ba
1882c19:dd:d9:dd:c25:c25:94de:83bb/1282c19:dd:d9:dd:c25:c25:94de:83bb
1892c19:dd:d9:dd:c25:c25:94de:83bc/1282c19:dd:d9:dd:c25:c25:94de:83bc
1902c19:dd:d9:dd:c25:c25:94de:83bd/1282c19:dd:d9:dd:c25:c25:94de:83bd
1912c19:dd:d9:dd:c25:c25:94de:83be/1282c19:dd:d9:dd:c25:c25:94de:83be
1922c19:dd:d9:dd:c25:c25:94de:83bf/1282c19:dd:d9:dd:c25:c25:94de:83bf
1932c19:dd:d9:dd:c25:c25:94de:83c0/1282c19:dd:d9:dd:c25:c25:94de:83c0
1942c19:dd:d9:dd:c25:c25:94de:83c1/1282c19:dd:d9:dd:c25:c25:94de:83c1
1952c19:dd:d9:dd:c25:c25:94de:83c2/1282c19:dd:d9:dd:c25:c25:94de:83c2
1962c19:dd:d9:dd:c25:c25:94de:83c3/1282c19:dd:d9:dd:c25:c25:94de:83c3
1972c19:dd:d9:dd:c25:c25:94de:83c4/1282c19:dd:d9:dd:c25:c25:94de:83c4
1982c19:dd:d9:dd:c25:c25:94de:83c5/1282c19:dd:d9:dd:c25:c25:94de:83c5
1992c19:dd:d9:dd:c25:c25:94de:83c6/1282c19:dd:d9:dd:c25:c25:94de:83c6
2002c19:dd:d9:dd:c25:c25:94de:83c7/1282c19:dd:d9:dd:c25:c25:94de:83c7
2012c19:dd:d9:dd:c25:c25:94de:83c8/1282c19:dd:d9:dd:c25:c25:94de:83c8
2022c19:dd:d9:dd:c25:c25:94de:83c9/1282c19:dd:d9:dd:c25:c25:94de:83c9
2032c19:dd:d9:dd:c25:c25:94de:83ca/1282c19:dd:d9:dd:c25:c25:94de:83ca
2042c19:dd:d9:dd:c25:c25:94de:83cb/1282c19:dd:d9:dd:c25:c25:94de:83cb
2052c19:dd:d9:dd:c25:c25:94de:83cc/1282c19:dd:d9:dd:c25:c25:94de:83cc
2062c19:dd:d9:dd:c25:c25:94de:83cd/1282c19:dd:d9:dd:c25:c25:94de:83cd
2072c19:dd:d9:dd:c25:c25:94de:83ce/1282c19:dd:d9:dd:c25:c25:94de:83ce
2082c19:dd:d9:dd:c25:c25:94de:83cf/1282c19:dd:d9:dd:c25:c25:94de:83cf
2092c19:dd:d9:dd:c25:c25:94de:83d0/1282c19:dd:d9:dd:c25:c25:94de:83d0
2102c19:dd:d9:dd:c25:c25:94de:83d1/1282c19:dd:d9:dd:c25:c25:94de:83d1
2112c19:dd:d9:dd:c25:c25:94de:83d2/1282c19:dd:d9:dd:c25:c25:94de:83d2
2122c19:dd:d9:dd:c25:c25:94de:83d3/1282c19:dd:d9:dd:c25:c25:94de:83d3
2132c19:dd:d9:dd:c25:c25:94de:83d4/1282c19:dd:d9:dd:c25:c25:94de:83d4
2142c19:dd:d9:dd:c25:c25:94de:83d5/1282c19:dd:d9:dd:c25:c25:94de:83d5
2152c19:dd:d9:dd:c25:c25:94de:83d6/1282c19:dd:d9:dd:c25:c25:94de:83d6
2162c19:dd:d9:dd:c25:c25:94de:83d7/1282c19:dd:d9:dd:c25:c25:94de:83d7
2172c19:dd:d9:dd:c25:c25:94de:83d8/1282c19:dd:d9:dd:c25:c25:94de:83d8
2182c19:dd:d9:dd:c25:c25:94de:83d9/1282c19:dd:d9:dd:c25:c25:94de:83d9
2192c19:dd:d9:dd:c25:c25:94de:83da/1282c19:dd:d9:dd:c25:c25:94de:83da
2202c19:dd:d9:dd:c25:c25:94de:83db/1282c19:dd:d9:dd:c25:c25:94de:83db
2212c19:dd:d9:dd:c25:c25:94de:83dc/1282c19:dd:d9:dd:c25:c25:94de:83dc
2222c19:dd:d9:dd:c25:c25:94de:83dd/1282c19:dd:d9:dd:c25:c25:94de:83dd
2232c19:dd:d9:dd:c25:c25:94de:83de/1282c19:dd:d9:dd:c25:c25:94de:83de
2242c19:dd:d9:dd:c25:c25:94de:83df/1282c19:dd:d9:dd:c25:c25:94de:83df
2252c19:dd:d9:dd:c25:c25:94de:83e0/1282c19:dd:d9:dd:c25:c25:94de:83e0
2262c19:dd:d9:dd:c25:c25:94de:83e1/1282c19:dd:d9:dd:c25:c25:94de:83e1
2272c19:dd:d9:dd:c25:c25:94de:83e2/1282c19:dd:d9:dd:c25:c25:94de:83e2
2282c19:dd:d9:dd:c25:c25:94de:83e3/1282c19:dd:d9:dd:c25:c25:94de:83e3
2292c19:dd:d9:dd:c25:c25:94de:83e4/1282c19:dd:d9:dd:c25:c25:94de:83e4
2302c19:dd:d9:dd:c25:c25:94de:83e5/1282c19:dd:d9:dd:c25:c25:94de:83e5
2312c19:dd:d9:dd:c25:c25:94de:83e6/1282c19:dd:d9:dd:c25:c25:94de:83e6
2322c19:dd:d9:dd:c25:c25:94de:83e7/1282c19:dd:d9:dd:c25:c25:94de:83e7
2332c19:dd:d9:dd:c25:c25:94de:83e8/1282c19:dd:d9:dd:c25:c25:94de:83e8
2342c19:dd:d9:dd:c25:c25:94de:83e9/1282c19:dd:d9:dd:c25:c25:94de:83e9
2352c19:dd:d9:dd:c25:c25:94de:83ea/1282c19:dd:d9:dd:c25:c25:94de:83ea
2362c19:dd:d9:dd:c25:c25:94de:83eb/1282c19:dd:d9:dd:c25:c25:94de:83eb
2372c19:dd:d9:dd:c25:c25:94de:83ec/1282c19:dd:d9:dd:c25:c25:94de:83ec
2382c19:dd:d9:dd:c25:c25:94de:83ed/1282c19:dd:d9:dd:c25:c25:94de:83ed
2392c19:dd:d9:dd:c25:c25:94de:83ee/1282c19:dd:d9:dd:c25:c25:94de:83ee
2402c19:dd:d9:dd:c25:c25:94de:83ef/1282c19:dd:d9:dd:c25:c25:94de:83ef
2412c19:dd:d9:dd:c25:c25:94de:83f0/1282c19:dd:d9:dd:c25:c25:94de:83f0
2422c19:dd:d9:dd:c25:c25:94de:83f1/1282c19:dd:d9:dd:c25:c25:94de:83f1
2432c19:dd:d9:dd:c25:c25:94de:83f2/1282c19:dd:d9:dd:c25:c25:94de:83f2
2442c19:dd:d9:dd:c25:c25:94de:83f3/1282c19:dd:d9:dd:c25:c25:94de:83f3
2452c19:dd:d9:dd:c25:c25:94de:83f4/1282c19:dd:d9:dd:c25:c25:94de:83f4
2462c19:dd:d9:dd:c25:c25:94de:83f5/1282c19:dd:d9:dd:c25:c25:94de:83f5
2472c19:dd:d9:dd:c25:c25:94de:83f6/1282c19:dd:d9:dd:c25:c25:94de:83f6
2482c19:dd:d9:dd:c25:c25:94de:83f7/1282c19:dd:d9:dd:c25:c25:94de:83f7
2492c19:dd:d9:dd:c25:c25:94de:83f8/1282c19:dd:d9:dd:c25:c25:94de:83f8
2502c19:dd:d9:dd:c25:c25:94de:83f9/1282c19:dd:d9:dd:c25:c25:94de:83f9
2512c19:dd:d9:dd:c25:c25:94de:83fa/1282c19:dd:d9:dd:c25:c25:94de:83fa
2522c19:dd:d9:dd:c25:c25:94de:83fb/1282c19:dd:d9:dd:c25:c25:94de:83fb
2532c19:dd:d9:dd:c25:c25:94de:83fc/1282c19:dd:d9:dd:c25:c25:94de:83fc
2542c19:dd:d9:dd:c25:c25:94de:83fd/1282c19:dd:d9:dd:c25:c25:94de:83fd
2552c19:dd:d9:dd:c25:c25:94de:83fe/1282c19:dd:d9:dd:c25:c25:94de:83fe
2562c19:dd:d9:dd:c25:c25:94de:83ff/1282c19:dd:d9:dd:c25:c25:94de:83ff

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.