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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:3300/120
First address
2c19:dd:d9:dd:c25:c25:94de:3300
Last address
2c19:dd:d9:dd:c25:c25:94de:33ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:3300
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.3.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:3300/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:3300/1282c19:dd:d9:dd:c25:c25:94de:3300
22c19:dd:d9:dd:c25:c25:94de:3301/1282c19:dd:d9:dd:c25:c25:94de:3301
32c19:dd:d9:dd:c25:c25:94de:3302/1282c19:dd:d9:dd:c25:c25:94de:3302
42c19:dd:d9:dd:c25:c25:94de:3303/1282c19:dd:d9:dd:c25:c25:94de:3303
52c19:dd:d9:dd:c25:c25:94de:3304/1282c19:dd:d9:dd:c25:c25:94de:3304
62c19:dd:d9:dd:c25:c25:94de:3305/1282c19:dd:d9:dd:c25:c25:94de:3305
72c19:dd:d9:dd:c25:c25:94de:3306/1282c19:dd:d9:dd:c25:c25:94de:3306
82c19:dd:d9:dd:c25:c25:94de:3307/1282c19:dd:d9:dd:c25:c25:94de:3307
92c19:dd:d9:dd:c25:c25:94de:3308/1282c19:dd:d9:dd:c25:c25:94de:3308
102c19:dd:d9:dd:c25:c25:94de:3309/1282c19:dd:d9:dd:c25:c25:94de:3309
112c19:dd:d9:dd:c25:c25:94de:330a/1282c19:dd:d9:dd:c25:c25:94de:330a
122c19:dd:d9:dd:c25:c25:94de:330b/1282c19:dd:d9:dd:c25:c25:94de:330b
132c19:dd:d9:dd:c25:c25:94de:330c/1282c19:dd:d9:dd:c25:c25:94de:330c
142c19:dd:d9:dd:c25:c25:94de:330d/1282c19:dd:d9:dd:c25:c25:94de:330d
152c19:dd:d9:dd:c25:c25:94de:330e/1282c19:dd:d9:dd:c25:c25:94de:330e
162c19:dd:d9:dd:c25:c25:94de:330f/1282c19:dd:d9:dd:c25:c25:94de:330f
172c19:dd:d9:dd:c25:c25:94de:3310/1282c19:dd:d9:dd:c25:c25:94de:3310
182c19:dd:d9:dd:c25:c25:94de:3311/1282c19:dd:d9:dd:c25:c25:94de:3311
192c19:dd:d9:dd:c25:c25:94de:3312/1282c19:dd:d9:dd:c25:c25:94de:3312
202c19:dd:d9:dd:c25:c25:94de:3313/1282c19:dd:d9:dd:c25:c25:94de:3313
212c19:dd:d9:dd:c25:c25:94de:3314/1282c19:dd:d9:dd:c25:c25:94de:3314
222c19:dd:d9:dd:c25:c25:94de:3315/1282c19:dd:d9:dd:c25:c25:94de:3315
232c19:dd:d9:dd:c25:c25:94de:3316/1282c19:dd:d9:dd:c25:c25:94de:3316
242c19:dd:d9:dd:c25:c25:94de:3317/1282c19:dd:d9:dd:c25:c25:94de:3317
252c19:dd:d9:dd:c25:c25:94de:3318/1282c19:dd:d9:dd:c25:c25:94de:3318
262c19:dd:d9:dd:c25:c25:94de:3319/1282c19:dd:d9:dd:c25:c25:94de:3319
272c19:dd:d9:dd:c25:c25:94de:331a/1282c19:dd:d9:dd:c25:c25:94de:331a
282c19:dd:d9:dd:c25:c25:94de:331b/1282c19:dd:d9:dd:c25:c25:94de:331b
292c19:dd:d9:dd:c25:c25:94de:331c/1282c19:dd:d9:dd:c25:c25:94de:331c
302c19:dd:d9:dd:c25:c25:94de:331d/1282c19:dd:d9:dd:c25:c25:94de:331d
312c19:dd:d9:dd:c25:c25:94de:331e/1282c19:dd:d9:dd:c25:c25:94de:331e
322c19:dd:d9:dd:c25:c25:94de:331f/1282c19:dd:d9:dd:c25:c25:94de:331f
332c19:dd:d9:dd:c25:c25:94de:3320/1282c19:dd:d9:dd:c25:c25:94de:3320
342c19:dd:d9:dd:c25:c25:94de:3321/1282c19:dd:d9:dd:c25:c25:94de:3321
352c19:dd:d9:dd:c25:c25:94de:3322/1282c19:dd:d9:dd:c25:c25:94de:3322
362c19:dd:d9:dd:c25:c25:94de:3323/1282c19:dd:d9:dd:c25:c25:94de:3323
372c19:dd:d9:dd:c25:c25:94de:3324/1282c19:dd:d9:dd:c25:c25:94de:3324
382c19:dd:d9:dd:c25:c25:94de:3325/1282c19:dd:d9:dd:c25:c25:94de:3325
392c19:dd:d9:dd:c25:c25:94de:3326/1282c19:dd:d9:dd:c25:c25:94de:3326
402c19:dd:d9:dd:c25:c25:94de:3327/1282c19:dd:d9:dd:c25:c25:94de:3327
412c19:dd:d9:dd:c25:c25:94de:3328/1282c19:dd:d9:dd:c25:c25:94de:3328
422c19:dd:d9:dd:c25:c25:94de:3329/1282c19:dd:d9:dd:c25:c25:94de:3329
432c19:dd:d9:dd:c25:c25:94de:332a/1282c19:dd:d9:dd:c25:c25:94de:332a
442c19:dd:d9:dd:c25:c25:94de:332b/1282c19:dd:d9:dd:c25:c25:94de:332b
452c19:dd:d9:dd:c25:c25:94de:332c/1282c19:dd:d9:dd:c25:c25:94de:332c
462c19:dd:d9:dd:c25:c25:94de:332d/1282c19:dd:d9:dd:c25:c25:94de:332d
472c19:dd:d9:dd:c25:c25:94de:332e/1282c19:dd:d9:dd:c25:c25:94de:332e
482c19:dd:d9:dd:c25:c25:94de:332f/1282c19:dd:d9:dd:c25:c25:94de:332f
492c19:dd:d9:dd:c25:c25:94de:3330/1282c19:dd:d9:dd:c25:c25:94de:3330
502c19:dd:d9:dd:c25:c25:94de:3331/1282c19:dd:d9:dd:c25:c25:94de:3331
512c19:dd:d9:dd:c25:c25:94de:3332/1282c19:dd:d9:dd:c25:c25:94de:3332
522c19:dd:d9:dd:c25:c25:94de:3333/1282c19:dd:d9:dd:c25:c25:94de:3333
532c19:dd:d9:dd:c25:c25:94de:3334/1282c19:dd:d9:dd:c25:c25:94de:3334
542c19:dd:d9:dd:c25:c25:94de:3335/1282c19:dd:d9:dd:c25:c25:94de:3335
552c19:dd:d9:dd:c25:c25:94de:3336/1282c19:dd:d9:dd:c25:c25:94de:3336
562c19:dd:d9:dd:c25:c25:94de:3337/1282c19:dd:d9:dd:c25:c25:94de:3337
572c19:dd:d9:dd:c25:c25:94de:3338/1282c19:dd:d9:dd:c25:c25:94de:3338
582c19:dd:d9:dd:c25:c25:94de:3339/1282c19:dd:d9:dd:c25:c25:94de:3339
592c19:dd:d9:dd:c25:c25:94de:333a/1282c19:dd:d9:dd:c25:c25:94de:333a
602c19:dd:d9:dd:c25:c25:94de:333b/1282c19:dd:d9:dd:c25:c25:94de:333b
612c19:dd:d9:dd:c25:c25:94de:333c/1282c19:dd:d9:dd:c25:c25:94de:333c
622c19:dd:d9:dd:c25:c25:94de:333d/1282c19:dd:d9:dd:c25:c25:94de:333d
632c19:dd:d9:dd:c25:c25:94de:333e/1282c19:dd:d9:dd:c25:c25:94de:333e
642c19:dd:d9:dd:c25:c25:94de:333f/1282c19:dd:d9:dd:c25:c25:94de:333f
652c19:dd:d9:dd:c25:c25:94de:3340/1282c19:dd:d9:dd:c25:c25:94de:3340
662c19:dd:d9:dd:c25:c25:94de:3341/1282c19:dd:d9:dd:c25:c25:94de:3341
672c19:dd:d9:dd:c25:c25:94de:3342/1282c19:dd:d9:dd:c25:c25:94de:3342
682c19:dd:d9:dd:c25:c25:94de:3343/1282c19:dd:d9:dd:c25:c25:94de:3343
692c19:dd:d9:dd:c25:c25:94de:3344/1282c19:dd:d9:dd:c25:c25:94de:3344
702c19:dd:d9:dd:c25:c25:94de:3345/1282c19:dd:d9:dd:c25:c25:94de:3345
712c19:dd:d9:dd:c25:c25:94de:3346/1282c19:dd:d9:dd:c25:c25:94de:3346
722c19:dd:d9:dd:c25:c25:94de:3347/1282c19:dd:d9:dd:c25:c25:94de:3347
732c19:dd:d9:dd:c25:c25:94de:3348/1282c19:dd:d9:dd:c25:c25:94de:3348
742c19:dd:d9:dd:c25:c25:94de:3349/1282c19:dd:d9:dd:c25:c25:94de:3349
752c19:dd:d9:dd:c25:c25:94de:334a/1282c19:dd:d9:dd:c25:c25:94de:334a
762c19:dd:d9:dd:c25:c25:94de:334b/1282c19:dd:d9:dd:c25:c25:94de:334b
772c19:dd:d9:dd:c25:c25:94de:334c/1282c19:dd:d9:dd:c25:c25:94de:334c
782c19:dd:d9:dd:c25:c25:94de:334d/1282c19:dd:d9:dd:c25:c25:94de:334d
792c19:dd:d9:dd:c25:c25:94de:334e/1282c19:dd:d9:dd:c25:c25:94de:334e
802c19:dd:d9:dd:c25:c25:94de:334f/1282c19:dd:d9:dd:c25:c25:94de:334f
812c19:dd:d9:dd:c25:c25:94de:3350/1282c19:dd:d9:dd:c25:c25:94de:3350
822c19:dd:d9:dd:c25:c25:94de:3351/1282c19:dd:d9:dd:c25:c25:94de:3351
832c19:dd:d9:dd:c25:c25:94de:3352/1282c19:dd:d9:dd:c25:c25:94de:3352
842c19:dd:d9:dd:c25:c25:94de:3353/1282c19:dd:d9:dd:c25:c25:94de:3353
852c19:dd:d9:dd:c25:c25:94de:3354/1282c19:dd:d9:dd:c25:c25:94de:3354
862c19:dd:d9:dd:c25:c25:94de:3355/1282c19:dd:d9:dd:c25:c25:94de:3355
872c19:dd:d9:dd:c25:c25:94de:3356/1282c19:dd:d9:dd:c25:c25:94de:3356
882c19:dd:d9:dd:c25:c25:94de:3357/1282c19:dd:d9:dd:c25:c25:94de:3357
892c19:dd:d9:dd:c25:c25:94de:3358/1282c19:dd:d9:dd:c25:c25:94de:3358
902c19:dd:d9:dd:c25:c25:94de:3359/1282c19:dd:d9:dd:c25:c25:94de:3359
912c19:dd:d9:dd:c25:c25:94de:335a/1282c19:dd:d9:dd:c25:c25:94de:335a
922c19:dd:d9:dd:c25:c25:94de:335b/1282c19:dd:d9:dd:c25:c25:94de:335b
932c19:dd:d9:dd:c25:c25:94de:335c/1282c19:dd:d9:dd:c25:c25:94de:335c
942c19:dd:d9:dd:c25:c25:94de:335d/1282c19:dd:d9:dd:c25:c25:94de:335d
952c19:dd:d9:dd:c25:c25:94de:335e/1282c19:dd:d9:dd:c25:c25:94de:335e
962c19:dd:d9:dd:c25:c25:94de:335f/1282c19:dd:d9:dd:c25:c25:94de:335f
972c19:dd:d9:dd:c25:c25:94de:3360/1282c19:dd:d9:dd:c25:c25:94de:3360
982c19:dd:d9:dd:c25:c25:94de:3361/1282c19:dd:d9:dd:c25:c25:94de:3361
992c19:dd:d9:dd:c25:c25:94de:3362/1282c19:dd:d9:dd:c25:c25:94de:3362
1002c19:dd:d9:dd:c25:c25:94de:3363/1282c19:dd:d9:dd:c25:c25:94de:3363
1012c19:dd:d9:dd:c25:c25:94de:3364/1282c19:dd:d9:dd:c25:c25:94de:3364
1022c19:dd:d9:dd:c25:c25:94de:3365/1282c19:dd:d9:dd:c25:c25:94de:3365
1032c19:dd:d9:dd:c25:c25:94de:3366/1282c19:dd:d9:dd:c25:c25:94de:3366
1042c19:dd:d9:dd:c25:c25:94de:3367/1282c19:dd:d9:dd:c25:c25:94de:3367
1052c19:dd:d9:dd:c25:c25:94de:3368/1282c19:dd:d9:dd:c25:c25:94de:3368
1062c19:dd:d9:dd:c25:c25:94de:3369/1282c19:dd:d9:dd:c25:c25:94de:3369
1072c19:dd:d9:dd:c25:c25:94de:336a/1282c19:dd:d9:dd:c25:c25:94de:336a
1082c19:dd:d9:dd:c25:c25:94de:336b/1282c19:dd:d9:dd:c25:c25:94de:336b
1092c19:dd:d9:dd:c25:c25:94de:336c/1282c19:dd:d9:dd:c25:c25:94de:336c
1102c19:dd:d9:dd:c25:c25:94de:336d/1282c19:dd:d9:dd:c25:c25:94de:336d
1112c19:dd:d9:dd:c25:c25:94de:336e/1282c19:dd:d9:dd:c25:c25:94de:336e
1122c19:dd:d9:dd:c25:c25:94de:336f/1282c19:dd:d9:dd:c25:c25:94de:336f
1132c19:dd:d9:dd:c25:c25:94de:3370/1282c19:dd:d9:dd:c25:c25:94de:3370
1142c19:dd:d9:dd:c25:c25:94de:3371/1282c19:dd:d9:dd:c25:c25:94de:3371
1152c19:dd:d9:dd:c25:c25:94de:3372/1282c19:dd:d9:dd:c25:c25:94de:3372
1162c19:dd:d9:dd:c25:c25:94de:3373/1282c19:dd:d9:dd:c25:c25:94de:3373
1172c19:dd:d9:dd:c25:c25:94de:3374/1282c19:dd:d9:dd:c25:c25:94de:3374
1182c19:dd:d9:dd:c25:c25:94de:3375/1282c19:dd:d9:dd:c25:c25:94de:3375
1192c19:dd:d9:dd:c25:c25:94de:3376/1282c19:dd:d9:dd:c25:c25:94de:3376
1202c19:dd:d9:dd:c25:c25:94de:3377/1282c19:dd:d9:dd:c25:c25:94de:3377
1212c19:dd:d9:dd:c25:c25:94de:3378/1282c19:dd:d9:dd:c25:c25:94de:3378
1222c19:dd:d9:dd:c25:c25:94de:3379/1282c19:dd:d9:dd:c25:c25:94de:3379
1232c19:dd:d9:dd:c25:c25:94de:337a/1282c19:dd:d9:dd:c25:c25:94de:337a
1242c19:dd:d9:dd:c25:c25:94de:337b/1282c19:dd:d9:dd:c25:c25:94de:337b
1252c19:dd:d9:dd:c25:c25:94de:337c/1282c19:dd:d9:dd:c25:c25:94de:337c
1262c19:dd:d9:dd:c25:c25:94de:337d/1282c19:dd:d9:dd:c25:c25:94de:337d
1272c19:dd:d9:dd:c25:c25:94de:337e/1282c19:dd:d9:dd:c25:c25:94de:337e
1282c19:dd:d9:dd:c25:c25:94de:337f/1282c19:dd:d9:dd:c25:c25:94de:337f
1292c19:dd:d9:dd:c25:c25:94de:3380/1282c19:dd:d9:dd:c25:c25:94de:3380
1302c19:dd:d9:dd:c25:c25:94de:3381/1282c19:dd:d9:dd:c25:c25:94de:3381
1312c19:dd:d9:dd:c25:c25:94de:3382/1282c19:dd:d9:dd:c25:c25:94de:3382
1322c19:dd:d9:dd:c25:c25:94de:3383/1282c19:dd:d9:dd:c25:c25:94de:3383
1332c19:dd:d9:dd:c25:c25:94de:3384/1282c19:dd:d9:dd:c25:c25:94de:3384
1342c19:dd:d9:dd:c25:c25:94de:3385/1282c19:dd:d9:dd:c25:c25:94de:3385
1352c19:dd:d9:dd:c25:c25:94de:3386/1282c19:dd:d9:dd:c25:c25:94de:3386
1362c19:dd:d9:dd:c25:c25:94de:3387/1282c19:dd:d9:dd:c25:c25:94de:3387
1372c19:dd:d9:dd:c25:c25:94de:3388/1282c19:dd:d9:dd:c25:c25:94de:3388
1382c19:dd:d9:dd:c25:c25:94de:3389/1282c19:dd:d9:dd:c25:c25:94de:3389
1392c19:dd:d9:dd:c25:c25:94de:338a/1282c19:dd:d9:dd:c25:c25:94de:338a
1402c19:dd:d9:dd:c25:c25:94de:338b/1282c19:dd:d9:dd:c25:c25:94de:338b
1412c19:dd:d9:dd:c25:c25:94de:338c/1282c19:dd:d9:dd:c25:c25:94de:338c
1422c19:dd:d9:dd:c25:c25:94de:338d/1282c19:dd:d9:dd:c25:c25:94de:338d
1432c19:dd:d9:dd:c25:c25:94de:338e/1282c19:dd:d9:dd:c25:c25:94de:338e
1442c19:dd:d9:dd:c25:c25:94de:338f/1282c19:dd:d9:dd:c25:c25:94de:338f
1452c19:dd:d9:dd:c25:c25:94de:3390/1282c19:dd:d9:dd:c25:c25:94de:3390
1462c19:dd:d9:dd:c25:c25:94de:3391/1282c19:dd:d9:dd:c25:c25:94de:3391
1472c19:dd:d9:dd:c25:c25:94de:3392/1282c19:dd:d9:dd:c25:c25:94de:3392
1482c19:dd:d9:dd:c25:c25:94de:3393/1282c19:dd:d9:dd:c25:c25:94de:3393
1492c19:dd:d9:dd:c25:c25:94de:3394/1282c19:dd:d9:dd:c25:c25:94de:3394
1502c19:dd:d9:dd:c25:c25:94de:3395/1282c19:dd:d9:dd:c25:c25:94de:3395
1512c19:dd:d9:dd:c25:c25:94de:3396/1282c19:dd:d9:dd:c25:c25:94de:3396
1522c19:dd:d9:dd:c25:c25:94de:3397/1282c19:dd:d9:dd:c25:c25:94de:3397
1532c19:dd:d9:dd:c25:c25:94de:3398/1282c19:dd:d9:dd:c25:c25:94de:3398
1542c19:dd:d9:dd:c25:c25:94de:3399/1282c19:dd:d9:dd:c25:c25:94de:3399
1552c19:dd:d9:dd:c25:c25:94de:339a/1282c19:dd:d9:dd:c25:c25:94de:339a
1562c19:dd:d9:dd:c25:c25:94de:339b/1282c19:dd:d9:dd:c25:c25:94de:339b
1572c19:dd:d9:dd:c25:c25:94de:339c/1282c19:dd:d9:dd:c25:c25:94de:339c
1582c19:dd:d9:dd:c25:c25:94de:339d/1282c19:dd:d9:dd:c25:c25:94de:339d
1592c19:dd:d9:dd:c25:c25:94de:339e/1282c19:dd:d9:dd:c25:c25:94de:339e
1602c19:dd:d9:dd:c25:c25:94de:339f/1282c19:dd:d9:dd:c25:c25:94de:339f
1612c19:dd:d9:dd:c25:c25:94de:33a0/1282c19:dd:d9:dd:c25:c25:94de:33a0
1622c19:dd:d9:dd:c25:c25:94de:33a1/1282c19:dd:d9:dd:c25:c25:94de:33a1
1632c19:dd:d9:dd:c25:c25:94de:33a2/1282c19:dd:d9:dd:c25:c25:94de:33a2
1642c19:dd:d9:dd:c25:c25:94de:33a3/1282c19:dd:d9:dd:c25:c25:94de:33a3
1652c19:dd:d9:dd:c25:c25:94de:33a4/1282c19:dd:d9:dd:c25:c25:94de:33a4
1662c19:dd:d9:dd:c25:c25:94de:33a5/1282c19:dd:d9:dd:c25:c25:94de:33a5
1672c19:dd:d9:dd:c25:c25:94de:33a6/1282c19:dd:d9:dd:c25:c25:94de:33a6
1682c19:dd:d9:dd:c25:c25:94de:33a7/1282c19:dd:d9:dd:c25:c25:94de:33a7
1692c19:dd:d9:dd:c25:c25:94de:33a8/1282c19:dd:d9:dd:c25:c25:94de:33a8
1702c19:dd:d9:dd:c25:c25:94de:33a9/1282c19:dd:d9:dd:c25:c25:94de:33a9
1712c19:dd:d9:dd:c25:c25:94de:33aa/1282c19:dd:d9:dd:c25:c25:94de:33aa
1722c19:dd:d9:dd:c25:c25:94de:33ab/1282c19:dd:d9:dd:c25:c25:94de:33ab
1732c19:dd:d9:dd:c25:c25:94de:33ac/1282c19:dd:d9:dd:c25:c25:94de:33ac
1742c19:dd:d9:dd:c25:c25:94de:33ad/1282c19:dd:d9:dd:c25:c25:94de:33ad
1752c19:dd:d9:dd:c25:c25:94de:33ae/1282c19:dd:d9:dd:c25:c25:94de:33ae
1762c19:dd:d9:dd:c25:c25:94de:33af/1282c19:dd:d9:dd:c25:c25:94de:33af
1772c19:dd:d9:dd:c25:c25:94de:33b0/1282c19:dd:d9:dd:c25:c25:94de:33b0
1782c19:dd:d9:dd:c25:c25:94de:33b1/1282c19:dd:d9:dd:c25:c25:94de:33b1
1792c19:dd:d9:dd:c25:c25:94de:33b2/1282c19:dd:d9:dd:c25:c25:94de:33b2
1802c19:dd:d9:dd:c25:c25:94de:33b3/1282c19:dd:d9:dd:c25:c25:94de:33b3
1812c19:dd:d9:dd:c25:c25:94de:33b4/1282c19:dd:d9:dd:c25:c25:94de:33b4
1822c19:dd:d9:dd:c25:c25:94de:33b5/1282c19:dd:d9:dd:c25:c25:94de:33b5
1832c19:dd:d9:dd:c25:c25:94de:33b6/1282c19:dd:d9:dd:c25:c25:94de:33b6
1842c19:dd:d9:dd:c25:c25:94de:33b7/1282c19:dd:d9:dd:c25:c25:94de:33b7
1852c19:dd:d9:dd:c25:c25:94de:33b8/1282c19:dd:d9:dd:c25:c25:94de:33b8
1862c19:dd:d9:dd:c25:c25:94de:33b9/1282c19:dd:d9:dd:c25:c25:94de:33b9
1872c19:dd:d9:dd:c25:c25:94de:33ba/1282c19:dd:d9:dd:c25:c25:94de:33ba
1882c19:dd:d9:dd:c25:c25:94de:33bb/1282c19:dd:d9:dd:c25:c25:94de:33bb
1892c19:dd:d9:dd:c25:c25:94de:33bc/1282c19:dd:d9:dd:c25:c25:94de:33bc
1902c19:dd:d9:dd:c25:c25:94de:33bd/1282c19:dd:d9:dd:c25:c25:94de:33bd
1912c19:dd:d9:dd:c25:c25:94de:33be/1282c19:dd:d9:dd:c25:c25:94de:33be
1922c19:dd:d9:dd:c25:c25:94de:33bf/1282c19:dd:d9:dd:c25:c25:94de:33bf
1932c19:dd:d9:dd:c25:c25:94de:33c0/1282c19:dd:d9:dd:c25:c25:94de:33c0
1942c19:dd:d9:dd:c25:c25:94de:33c1/1282c19:dd:d9:dd:c25:c25:94de:33c1
1952c19:dd:d9:dd:c25:c25:94de:33c2/1282c19:dd:d9:dd:c25:c25:94de:33c2
1962c19:dd:d9:dd:c25:c25:94de:33c3/1282c19:dd:d9:dd:c25:c25:94de:33c3
1972c19:dd:d9:dd:c25:c25:94de:33c4/1282c19:dd:d9:dd:c25:c25:94de:33c4
1982c19:dd:d9:dd:c25:c25:94de:33c5/1282c19:dd:d9:dd:c25:c25:94de:33c5
1992c19:dd:d9:dd:c25:c25:94de:33c6/1282c19:dd:d9:dd:c25:c25:94de:33c6
2002c19:dd:d9:dd:c25:c25:94de:33c7/1282c19:dd:d9:dd:c25:c25:94de:33c7
2012c19:dd:d9:dd:c25:c25:94de:33c8/1282c19:dd:d9:dd:c25:c25:94de:33c8
2022c19:dd:d9:dd:c25:c25:94de:33c9/1282c19:dd:d9:dd:c25:c25:94de:33c9
2032c19:dd:d9:dd:c25:c25:94de:33ca/1282c19:dd:d9:dd:c25:c25:94de:33ca
2042c19:dd:d9:dd:c25:c25:94de:33cb/1282c19:dd:d9:dd:c25:c25:94de:33cb
2052c19:dd:d9:dd:c25:c25:94de:33cc/1282c19:dd:d9:dd:c25:c25:94de:33cc
2062c19:dd:d9:dd:c25:c25:94de:33cd/1282c19:dd:d9:dd:c25:c25:94de:33cd
2072c19:dd:d9:dd:c25:c25:94de:33ce/1282c19:dd:d9:dd:c25:c25:94de:33ce
2082c19:dd:d9:dd:c25:c25:94de:33cf/1282c19:dd:d9:dd:c25:c25:94de:33cf
2092c19:dd:d9:dd:c25:c25:94de:33d0/1282c19:dd:d9:dd:c25:c25:94de:33d0
2102c19:dd:d9:dd:c25:c25:94de:33d1/1282c19:dd:d9:dd:c25:c25:94de:33d1
2112c19:dd:d9:dd:c25:c25:94de:33d2/1282c19:dd:d9:dd:c25:c25:94de:33d2
2122c19:dd:d9:dd:c25:c25:94de:33d3/1282c19:dd:d9:dd:c25:c25:94de:33d3
2132c19:dd:d9:dd:c25:c25:94de:33d4/1282c19:dd:d9:dd:c25:c25:94de:33d4
2142c19:dd:d9:dd:c25:c25:94de:33d5/1282c19:dd:d9:dd:c25:c25:94de:33d5
2152c19:dd:d9:dd:c25:c25:94de:33d6/1282c19:dd:d9:dd:c25:c25:94de:33d6
2162c19:dd:d9:dd:c25:c25:94de:33d7/1282c19:dd:d9:dd:c25:c25:94de:33d7
2172c19:dd:d9:dd:c25:c25:94de:33d8/1282c19:dd:d9:dd:c25:c25:94de:33d8
2182c19:dd:d9:dd:c25:c25:94de:33d9/1282c19:dd:d9:dd:c25:c25:94de:33d9
2192c19:dd:d9:dd:c25:c25:94de:33da/1282c19:dd:d9:dd:c25:c25:94de:33da
2202c19:dd:d9:dd:c25:c25:94de:33db/1282c19:dd:d9:dd:c25:c25:94de:33db
2212c19:dd:d9:dd:c25:c25:94de:33dc/1282c19:dd:d9:dd:c25:c25:94de:33dc
2222c19:dd:d9:dd:c25:c25:94de:33dd/1282c19:dd:d9:dd:c25:c25:94de:33dd
2232c19:dd:d9:dd:c25:c25:94de:33de/1282c19:dd:d9:dd:c25:c25:94de:33de
2242c19:dd:d9:dd:c25:c25:94de:33df/1282c19:dd:d9:dd:c25:c25:94de:33df
2252c19:dd:d9:dd:c25:c25:94de:33e0/1282c19:dd:d9:dd:c25:c25:94de:33e0
2262c19:dd:d9:dd:c25:c25:94de:33e1/1282c19:dd:d9:dd:c25:c25:94de:33e1
2272c19:dd:d9:dd:c25:c25:94de:33e2/1282c19:dd:d9:dd:c25:c25:94de:33e2
2282c19:dd:d9:dd:c25:c25:94de:33e3/1282c19:dd:d9:dd:c25:c25:94de:33e3
2292c19:dd:d9:dd:c25:c25:94de:33e4/1282c19:dd:d9:dd:c25:c25:94de:33e4
2302c19:dd:d9:dd:c25:c25:94de:33e5/1282c19:dd:d9:dd:c25:c25:94de:33e5
2312c19:dd:d9:dd:c25:c25:94de:33e6/1282c19:dd:d9:dd:c25:c25:94de:33e6
2322c19:dd:d9:dd:c25:c25:94de:33e7/1282c19:dd:d9:dd:c25:c25:94de:33e7
2332c19:dd:d9:dd:c25:c25:94de:33e8/1282c19:dd:d9:dd:c25:c25:94de:33e8
2342c19:dd:d9:dd:c25:c25:94de:33e9/1282c19:dd:d9:dd:c25:c25:94de:33e9
2352c19:dd:d9:dd:c25:c25:94de:33ea/1282c19:dd:d9:dd:c25:c25:94de:33ea
2362c19:dd:d9:dd:c25:c25:94de:33eb/1282c19:dd:d9:dd:c25:c25:94de:33eb
2372c19:dd:d9:dd:c25:c25:94de:33ec/1282c19:dd:d9:dd:c25:c25:94de:33ec
2382c19:dd:d9:dd:c25:c25:94de:33ed/1282c19:dd:d9:dd:c25:c25:94de:33ed
2392c19:dd:d9:dd:c25:c25:94de:33ee/1282c19:dd:d9:dd:c25:c25:94de:33ee
2402c19:dd:d9:dd:c25:c25:94de:33ef/1282c19:dd:d9:dd:c25:c25:94de:33ef
2412c19:dd:d9:dd:c25:c25:94de:33f0/1282c19:dd:d9:dd:c25:c25:94de:33f0
2422c19:dd:d9:dd:c25:c25:94de:33f1/1282c19:dd:d9:dd:c25:c25:94de:33f1
2432c19:dd:d9:dd:c25:c25:94de:33f2/1282c19:dd:d9:dd:c25:c25:94de:33f2
2442c19:dd:d9:dd:c25:c25:94de:33f3/1282c19:dd:d9:dd:c25:c25:94de:33f3
2452c19:dd:d9:dd:c25:c25:94de:33f4/1282c19:dd:d9:dd:c25:c25:94de:33f4
2462c19:dd:d9:dd:c25:c25:94de:33f5/1282c19:dd:d9:dd:c25:c25:94de:33f5
2472c19:dd:d9:dd:c25:c25:94de:33f6/1282c19:dd:d9:dd:c25:c25:94de:33f6
2482c19:dd:d9:dd:c25:c25:94de:33f7/1282c19:dd:d9:dd:c25:c25:94de:33f7
2492c19:dd:d9:dd:c25:c25:94de:33f8/1282c19:dd:d9:dd:c25:c25:94de:33f8
2502c19:dd:d9:dd:c25:c25:94de:33f9/1282c19:dd:d9:dd:c25:c25:94de:33f9
2512c19:dd:d9:dd:c25:c25:94de:33fa/1282c19:dd:d9:dd:c25:c25:94de:33fa
2522c19:dd:d9:dd:c25:c25:94de:33fb/1282c19:dd:d9:dd:c25:c25:94de:33fb
2532c19:dd:d9:dd:c25:c25:94de:33fc/1282c19:dd:d9:dd:c25:c25:94de:33fc
2542c19:dd:d9:dd:c25:c25:94de:33fd/1282c19:dd:d9:dd:c25:c25:94de:33fd
2552c19:dd:d9:dd:c25:c25:94de:33fe/1282c19:dd:d9:dd:c25:c25:94de:33fe
2562c19:dd:d9:dd:c25:c25:94de:33ff/1282c19:dd:d9:dd:c25:c25:94de:33ff

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.