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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:2400/120
First address
2c19:dd:d9:dd:c25:c25:94de:2400
Last address
2c19:dd:d9:dd:c25:c25:94de:24ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:2400
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
4.2.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:2400/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:2400/1282c19:dd:d9:dd:c25:c25:94de:2400
22c19:dd:d9:dd:c25:c25:94de:2401/1282c19:dd:d9:dd:c25:c25:94de:2401
32c19:dd:d9:dd:c25:c25:94de:2402/1282c19:dd:d9:dd:c25:c25:94de:2402
42c19:dd:d9:dd:c25:c25:94de:2403/1282c19:dd:d9:dd:c25:c25:94de:2403
52c19:dd:d9:dd:c25:c25:94de:2404/1282c19:dd:d9:dd:c25:c25:94de:2404
62c19:dd:d9:dd:c25:c25:94de:2405/1282c19:dd:d9:dd:c25:c25:94de:2405
72c19:dd:d9:dd:c25:c25:94de:2406/1282c19:dd:d9:dd:c25:c25:94de:2406
82c19:dd:d9:dd:c25:c25:94de:2407/1282c19:dd:d9:dd:c25:c25:94de:2407
92c19:dd:d9:dd:c25:c25:94de:2408/1282c19:dd:d9:dd:c25:c25:94de:2408
102c19:dd:d9:dd:c25:c25:94de:2409/1282c19:dd:d9:dd:c25:c25:94de:2409
112c19:dd:d9:dd:c25:c25:94de:240a/1282c19:dd:d9:dd:c25:c25:94de:240a
122c19:dd:d9:dd:c25:c25:94de:240b/1282c19:dd:d9:dd:c25:c25:94de:240b
132c19:dd:d9:dd:c25:c25:94de:240c/1282c19:dd:d9:dd:c25:c25:94de:240c
142c19:dd:d9:dd:c25:c25:94de:240d/1282c19:dd:d9:dd:c25:c25:94de:240d
152c19:dd:d9:dd:c25:c25:94de:240e/1282c19:dd:d9:dd:c25:c25:94de:240e
162c19:dd:d9:dd:c25:c25:94de:240f/1282c19:dd:d9:dd:c25:c25:94de:240f
172c19:dd:d9:dd:c25:c25:94de:2410/1282c19:dd:d9:dd:c25:c25:94de:2410
182c19:dd:d9:dd:c25:c25:94de:2411/1282c19:dd:d9:dd:c25:c25:94de:2411
192c19:dd:d9:dd:c25:c25:94de:2412/1282c19:dd:d9:dd:c25:c25:94de:2412
202c19:dd:d9:dd:c25:c25:94de:2413/1282c19:dd:d9:dd:c25:c25:94de:2413
212c19:dd:d9:dd:c25:c25:94de:2414/1282c19:dd:d9:dd:c25:c25:94de:2414
222c19:dd:d9:dd:c25:c25:94de:2415/1282c19:dd:d9:dd:c25:c25:94de:2415
232c19:dd:d9:dd:c25:c25:94de:2416/1282c19:dd:d9:dd:c25:c25:94de:2416
242c19:dd:d9:dd:c25:c25:94de:2417/1282c19:dd:d9:dd:c25:c25:94de:2417
252c19:dd:d9:dd:c25:c25:94de:2418/1282c19:dd:d9:dd:c25:c25:94de:2418
262c19:dd:d9:dd:c25:c25:94de:2419/1282c19:dd:d9:dd:c25:c25:94de:2419
272c19:dd:d9:dd:c25:c25:94de:241a/1282c19:dd:d9:dd:c25:c25:94de:241a
282c19:dd:d9:dd:c25:c25:94de:241b/1282c19:dd:d9:dd:c25:c25:94de:241b
292c19:dd:d9:dd:c25:c25:94de:241c/1282c19:dd:d9:dd:c25:c25:94de:241c
302c19:dd:d9:dd:c25:c25:94de:241d/1282c19:dd:d9:dd:c25:c25:94de:241d
312c19:dd:d9:dd:c25:c25:94de:241e/1282c19:dd:d9:dd:c25:c25:94de:241e
322c19:dd:d9:dd:c25:c25:94de:241f/1282c19:dd:d9:dd:c25:c25:94de:241f
332c19:dd:d9:dd:c25:c25:94de:2420/1282c19:dd:d9:dd:c25:c25:94de:2420
342c19:dd:d9:dd:c25:c25:94de:2421/1282c19:dd:d9:dd:c25:c25:94de:2421
352c19:dd:d9:dd:c25:c25:94de:2422/1282c19:dd:d9:dd:c25:c25:94de:2422
362c19:dd:d9:dd:c25:c25:94de:2423/1282c19:dd:d9:dd:c25:c25:94de:2423
372c19:dd:d9:dd:c25:c25:94de:2424/1282c19:dd:d9:dd:c25:c25:94de:2424
382c19:dd:d9:dd:c25:c25:94de:2425/1282c19:dd:d9:dd:c25:c25:94de:2425
392c19:dd:d9:dd:c25:c25:94de:2426/1282c19:dd:d9:dd:c25:c25:94de:2426
402c19:dd:d9:dd:c25:c25:94de:2427/1282c19:dd:d9:dd:c25:c25:94de:2427
412c19:dd:d9:dd:c25:c25:94de:2428/1282c19:dd:d9:dd:c25:c25:94de:2428
422c19:dd:d9:dd:c25:c25:94de:2429/1282c19:dd:d9:dd:c25:c25:94de:2429
432c19:dd:d9:dd:c25:c25:94de:242a/1282c19:dd:d9:dd:c25:c25:94de:242a
442c19:dd:d9:dd:c25:c25:94de:242b/1282c19:dd:d9:dd:c25:c25:94de:242b
452c19:dd:d9:dd:c25:c25:94de:242c/1282c19:dd:d9:dd:c25:c25:94de:242c
462c19:dd:d9:dd:c25:c25:94de:242d/1282c19:dd:d9:dd:c25:c25:94de:242d
472c19:dd:d9:dd:c25:c25:94de:242e/1282c19:dd:d9:dd:c25:c25:94de:242e
482c19:dd:d9:dd:c25:c25:94de:242f/1282c19:dd:d9:dd:c25:c25:94de:242f
492c19:dd:d9:dd:c25:c25:94de:2430/1282c19:dd:d9:dd:c25:c25:94de:2430
502c19:dd:d9:dd:c25:c25:94de:2431/1282c19:dd:d9:dd:c25:c25:94de:2431
512c19:dd:d9:dd:c25:c25:94de:2432/1282c19:dd:d9:dd:c25:c25:94de:2432
522c19:dd:d9:dd:c25:c25:94de:2433/1282c19:dd:d9:dd:c25:c25:94de:2433
532c19:dd:d9:dd:c25:c25:94de:2434/1282c19:dd:d9:dd:c25:c25:94de:2434
542c19:dd:d9:dd:c25:c25:94de:2435/1282c19:dd:d9:dd:c25:c25:94de:2435
552c19:dd:d9:dd:c25:c25:94de:2436/1282c19:dd:d9:dd:c25:c25:94de:2436
562c19:dd:d9:dd:c25:c25:94de:2437/1282c19:dd:d9:dd:c25:c25:94de:2437
572c19:dd:d9:dd:c25:c25:94de:2438/1282c19:dd:d9:dd:c25:c25:94de:2438
582c19:dd:d9:dd:c25:c25:94de:2439/1282c19:dd:d9:dd:c25:c25:94de:2439
592c19:dd:d9:dd:c25:c25:94de:243a/1282c19:dd:d9:dd:c25:c25:94de:243a
602c19:dd:d9:dd:c25:c25:94de:243b/1282c19:dd:d9:dd:c25:c25:94de:243b
612c19:dd:d9:dd:c25:c25:94de:243c/1282c19:dd:d9:dd:c25:c25:94de:243c
622c19:dd:d9:dd:c25:c25:94de:243d/1282c19:dd:d9:dd:c25:c25:94de:243d
632c19:dd:d9:dd:c25:c25:94de:243e/1282c19:dd:d9:dd:c25:c25:94de:243e
642c19:dd:d9:dd:c25:c25:94de:243f/1282c19:dd:d9:dd:c25:c25:94de:243f
652c19:dd:d9:dd:c25:c25:94de:2440/1282c19:dd:d9:dd:c25:c25:94de:2440
662c19:dd:d9:dd:c25:c25:94de:2441/1282c19:dd:d9:dd:c25:c25:94de:2441
672c19:dd:d9:dd:c25:c25:94de:2442/1282c19:dd:d9:dd:c25:c25:94de:2442
682c19:dd:d9:dd:c25:c25:94de:2443/1282c19:dd:d9:dd:c25:c25:94de:2443
692c19:dd:d9:dd:c25:c25:94de:2444/1282c19:dd:d9:dd:c25:c25:94de:2444
702c19:dd:d9:dd:c25:c25:94de:2445/1282c19:dd:d9:dd:c25:c25:94de:2445
712c19:dd:d9:dd:c25:c25:94de:2446/1282c19:dd:d9:dd:c25:c25:94de:2446
722c19:dd:d9:dd:c25:c25:94de:2447/1282c19:dd:d9:dd:c25:c25:94de:2447
732c19:dd:d9:dd:c25:c25:94de:2448/1282c19:dd:d9:dd:c25:c25:94de:2448
742c19:dd:d9:dd:c25:c25:94de:2449/1282c19:dd:d9:dd:c25:c25:94de:2449
752c19:dd:d9:dd:c25:c25:94de:244a/1282c19:dd:d9:dd:c25:c25:94de:244a
762c19:dd:d9:dd:c25:c25:94de:244b/1282c19:dd:d9:dd:c25:c25:94de:244b
772c19:dd:d9:dd:c25:c25:94de:244c/1282c19:dd:d9:dd:c25:c25:94de:244c
782c19:dd:d9:dd:c25:c25:94de:244d/1282c19:dd:d9:dd:c25:c25:94de:244d
792c19:dd:d9:dd:c25:c25:94de:244e/1282c19:dd:d9:dd:c25:c25:94de:244e
802c19:dd:d9:dd:c25:c25:94de:244f/1282c19:dd:d9:dd:c25:c25:94de:244f
812c19:dd:d9:dd:c25:c25:94de:2450/1282c19:dd:d9:dd:c25:c25:94de:2450
822c19:dd:d9:dd:c25:c25:94de:2451/1282c19:dd:d9:dd:c25:c25:94de:2451
832c19:dd:d9:dd:c25:c25:94de:2452/1282c19:dd:d9:dd:c25:c25:94de:2452
842c19:dd:d9:dd:c25:c25:94de:2453/1282c19:dd:d9:dd:c25:c25:94de:2453
852c19:dd:d9:dd:c25:c25:94de:2454/1282c19:dd:d9:dd:c25:c25:94de:2454
862c19:dd:d9:dd:c25:c25:94de:2455/1282c19:dd:d9:dd:c25:c25:94de:2455
872c19:dd:d9:dd:c25:c25:94de:2456/1282c19:dd:d9:dd:c25:c25:94de:2456
882c19:dd:d9:dd:c25:c25:94de:2457/1282c19:dd:d9:dd:c25:c25:94de:2457
892c19:dd:d9:dd:c25:c25:94de:2458/1282c19:dd:d9:dd:c25:c25:94de:2458
902c19:dd:d9:dd:c25:c25:94de:2459/1282c19:dd:d9:dd:c25:c25:94de:2459
912c19:dd:d9:dd:c25:c25:94de:245a/1282c19:dd:d9:dd:c25:c25:94de:245a
922c19:dd:d9:dd:c25:c25:94de:245b/1282c19:dd:d9:dd:c25:c25:94de:245b
932c19:dd:d9:dd:c25:c25:94de:245c/1282c19:dd:d9:dd:c25:c25:94de:245c
942c19:dd:d9:dd:c25:c25:94de:245d/1282c19:dd:d9:dd:c25:c25:94de:245d
952c19:dd:d9:dd:c25:c25:94de:245e/1282c19:dd:d9:dd:c25:c25:94de:245e
962c19:dd:d9:dd:c25:c25:94de:245f/1282c19:dd:d9:dd:c25:c25:94de:245f
972c19:dd:d9:dd:c25:c25:94de:2460/1282c19:dd:d9:dd:c25:c25:94de:2460
982c19:dd:d9:dd:c25:c25:94de:2461/1282c19:dd:d9:dd:c25:c25:94de:2461
992c19:dd:d9:dd:c25:c25:94de:2462/1282c19:dd:d9:dd:c25:c25:94de:2462
1002c19:dd:d9:dd:c25:c25:94de:2463/1282c19:dd:d9:dd:c25:c25:94de:2463
1012c19:dd:d9:dd:c25:c25:94de:2464/1282c19:dd:d9:dd:c25:c25:94de:2464
1022c19:dd:d9:dd:c25:c25:94de:2465/1282c19:dd:d9:dd:c25:c25:94de:2465
1032c19:dd:d9:dd:c25:c25:94de:2466/1282c19:dd:d9:dd:c25:c25:94de:2466
1042c19:dd:d9:dd:c25:c25:94de:2467/1282c19:dd:d9:dd:c25:c25:94de:2467
1052c19:dd:d9:dd:c25:c25:94de:2468/1282c19:dd:d9:dd:c25:c25:94de:2468
1062c19:dd:d9:dd:c25:c25:94de:2469/1282c19:dd:d9:dd:c25:c25:94de:2469
1072c19:dd:d9:dd:c25:c25:94de:246a/1282c19:dd:d9:dd:c25:c25:94de:246a
1082c19:dd:d9:dd:c25:c25:94de:246b/1282c19:dd:d9:dd:c25:c25:94de:246b
1092c19:dd:d9:dd:c25:c25:94de:246c/1282c19:dd:d9:dd:c25:c25:94de:246c
1102c19:dd:d9:dd:c25:c25:94de:246d/1282c19:dd:d9:dd:c25:c25:94de:246d
1112c19:dd:d9:dd:c25:c25:94de:246e/1282c19:dd:d9:dd:c25:c25:94de:246e
1122c19:dd:d9:dd:c25:c25:94de:246f/1282c19:dd:d9:dd:c25:c25:94de:246f
1132c19:dd:d9:dd:c25:c25:94de:2470/1282c19:dd:d9:dd:c25:c25:94de:2470
1142c19:dd:d9:dd:c25:c25:94de:2471/1282c19:dd:d9:dd:c25:c25:94de:2471
1152c19:dd:d9:dd:c25:c25:94de:2472/1282c19:dd:d9:dd:c25:c25:94de:2472
1162c19:dd:d9:dd:c25:c25:94de:2473/1282c19:dd:d9:dd:c25:c25:94de:2473
1172c19:dd:d9:dd:c25:c25:94de:2474/1282c19:dd:d9:dd:c25:c25:94de:2474
1182c19:dd:d9:dd:c25:c25:94de:2475/1282c19:dd:d9:dd:c25:c25:94de:2475
1192c19:dd:d9:dd:c25:c25:94de:2476/1282c19:dd:d9:dd:c25:c25:94de:2476
1202c19:dd:d9:dd:c25:c25:94de:2477/1282c19:dd:d9:dd:c25:c25:94de:2477
1212c19:dd:d9:dd:c25:c25:94de:2478/1282c19:dd:d9:dd:c25:c25:94de:2478
1222c19:dd:d9:dd:c25:c25:94de:2479/1282c19:dd:d9:dd:c25:c25:94de:2479
1232c19:dd:d9:dd:c25:c25:94de:247a/1282c19:dd:d9:dd:c25:c25:94de:247a
1242c19:dd:d9:dd:c25:c25:94de:247b/1282c19:dd:d9:dd:c25:c25:94de:247b
1252c19:dd:d9:dd:c25:c25:94de:247c/1282c19:dd:d9:dd:c25:c25:94de:247c
1262c19:dd:d9:dd:c25:c25:94de:247d/1282c19:dd:d9:dd:c25:c25:94de:247d
1272c19:dd:d9:dd:c25:c25:94de:247e/1282c19:dd:d9:dd:c25:c25:94de:247e
1282c19:dd:d9:dd:c25:c25:94de:247f/1282c19:dd:d9:dd:c25:c25:94de:247f
1292c19:dd:d9:dd:c25:c25:94de:2480/1282c19:dd:d9:dd:c25:c25:94de:2480
1302c19:dd:d9:dd:c25:c25:94de:2481/1282c19:dd:d9:dd:c25:c25:94de:2481
1312c19:dd:d9:dd:c25:c25:94de:2482/1282c19:dd:d9:dd:c25:c25:94de:2482
1322c19:dd:d9:dd:c25:c25:94de:2483/1282c19:dd:d9:dd:c25:c25:94de:2483
1332c19:dd:d9:dd:c25:c25:94de:2484/1282c19:dd:d9:dd:c25:c25:94de:2484
1342c19:dd:d9:dd:c25:c25:94de:2485/1282c19:dd:d9:dd:c25:c25:94de:2485
1352c19:dd:d9:dd:c25:c25:94de:2486/1282c19:dd:d9:dd:c25:c25:94de:2486
1362c19:dd:d9:dd:c25:c25:94de:2487/1282c19:dd:d9:dd:c25:c25:94de:2487
1372c19:dd:d9:dd:c25:c25:94de:2488/1282c19:dd:d9:dd:c25:c25:94de:2488
1382c19:dd:d9:dd:c25:c25:94de:2489/1282c19:dd:d9:dd:c25:c25:94de:2489
1392c19:dd:d9:dd:c25:c25:94de:248a/1282c19:dd:d9:dd:c25:c25:94de:248a
1402c19:dd:d9:dd:c25:c25:94de:248b/1282c19:dd:d9:dd:c25:c25:94de:248b
1412c19:dd:d9:dd:c25:c25:94de:248c/1282c19:dd:d9:dd:c25:c25:94de:248c
1422c19:dd:d9:dd:c25:c25:94de:248d/1282c19:dd:d9:dd:c25:c25:94de:248d
1432c19:dd:d9:dd:c25:c25:94de:248e/1282c19:dd:d9:dd:c25:c25:94de:248e
1442c19:dd:d9:dd:c25:c25:94de:248f/1282c19:dd:d9:dd:c25:c25:94de:248f
1452c19:dd:d9:dd:c25:c25:94de:2490/1282c19:dd:d9:dd:c25:c25:94de:2490
1462c19:dd:d9:dd:c25:c25:94de:2491/1282c19:dd:d9:dd:c25:c25:94de:2491
1472c19:dd:d9:dd:c25:c25:94de:2492/1282c19:dd:d9:dd:c25:c25:94de:2492
1482c19:dd:d9:dd:c25:c25:94de:2493/1282c19:dd:d9:dd:c25:c25:94de:2493
1492c19:dd:d9:dd:c25:c25:94de:2494/1282c19:dd:d9:dd:c25:c25:94de:2494
1502c19:dd:d9:dd:c25:c25:94de:2495/1282c19:dd:d9:dd:c25:c25:94de:2495
1512c19:dd:d9:dd:c25:c25:94de:2496/1282c19:dd:d9:dd:c25:c25:94de:2496
1522c19:dd:d9:dd:c25:c25:94de:2497/1282c19:dd:d9:dd:c25:c25:94de:2497
1532c19:dd:d9:dd:c25:c25:94de:2498/1282c19:dd:d9:dd:c25:c25:94de:2498
1542c19:dd:d9:dd:c25:c25:94de:2499/1282c19:dd:d9:dd:c25:c25:94de:2499
1552c19:dd:d9:dd:c25:c25:94de:249a/1282c19:dd:d9:dd:c25:c25:94de:249a
1562c19:dd:d9:dd:c25:c25:94de:249b/1282c19:dd:d9:dd:c25:c25:94de:249b
1572c19:dd:d9:dd:c25:c25:94de:249c/1282c19:dd:d9:dd:c25:c25:94de:249c
1582c19:dd:d9:dd:c25:c25:94de:249d/1282c19:dd:d9:dd:c25:c25:94de:249d
1592c19:dd:d9:dd:c25:c25:94de:249e/1282c19:dd:d9:dd:c25:c25:94de:249e
1602c19:dd:d9:dd:c25:c25:94de:249f/1282c19:dd:d9:dd:c25:c25:94de:249f
1612c19:dd:d9:dd:c25:c25:94de:24a0/1282c19:dd:d9:dd:c25:c25:94de:24a0
1622c19:dd:d9:dd:c25:c25:94de:24a1/1282c19:dd:d9:dd:c25:c25:94de:24a1
1632c19:dd:d9:dd:c25:c25:94de:24a2/1282c19:dd:d9:dd:c25:c25:94de:24a2
1642c19:dd:d9:dd:c25:c25:94de:24a3/1282c19:dd:d9:dd:c25:c25:94de:24a3
1652c19:dd:d9:dd:c25:c25:94de:24a4/1282c19:dd:d9:dd:c25:c25:94de:24a4
1662c19:dd:d9:dd:c25:c25:94de:24a5/1282c19:dd:d9:dd:c25:c25:94de:24a5
1672c19:dd:d9:dd:c25:c25:94de:24a6/1282c19:dd:d9:dd:c25:c25:94de:24a6
1682c19:dd:d9:dd:c25:c25:94de:24a7/1282c19:dd:d9:dd:c25:c25:94de:24a7
1692c19:dd:d9:dd:c25:c25:94de:24a8/1282c19:dd:d9:dd:c25:c25:94de:24a8
1702c19:dd:d9:dd:c25:c25:94de:24a9/1282c19:dd:d9:dd:c25:c25:94de:24a9
1712c19:dd:d9:dd:c25:c25:94de:24aa/1282c19:dd:d9:dd:c25:c25:94de:24aa
1722c19:dd:d9:dd:c25:c25:94de:24ab/1282c19:dd:d9:dd:c25:c25:94de:24ab
1732c19:dd:d9:dd:c25:c25:94de:24ac/1282c19:dd:d9:dd:c25:c25:94de:24ac
1742c19:dd:d9:dd:c25:c25:94de:24ad/1282c19:dd:d9:dd:c25:c25:94de:24ad
1752c19:dd:d9:dd:c25:c25:94de:24ae/1282c19:dd:d9:dd:c25:c25:94de:24ae
1762c19:dd:d9:dd:c25:c25:94de:24af/1282c19:dd:d9:dd:c25:c25:94de:24af
1772c19:dd:d9:dd:c25:c25:94de:24b0/1282c19:dd:d9:dd:c25:c25:94de:24b0
1782c19:dd:d9:dd:c25:c25:94de:24b1/1282c19:dd:d9:dd:c25:c25:94de:24b1
1792c19:dd:d9:dd:c25:c25:94de:24b2/1282c19:dd:d9:dd:c25:c25:94de:24b2
1802c19:dd:d9:dd:c25:c25:94de:24b3/1282c19:dd:d9:dd:c25:c25:94de:24b3
1812c19:dd:d9:dd:c25:c25:94de:24b4/1282c19:dd:d9:dd:c25:c25:94de:24b4
1822c19:dd:d9:dd:c25:c25:94de:24b5/1282c19:dd:d9:dd:c25:c25:94de:24b5
1832c19:dd:d9:dd:c25:c25:94de:24b6/1282c19:dd:d9:dd:c25:c25:94de:24b6
1842c19:dd:d9:dd:c25:c25:94de:24b7/1282c19:dd:d9:dd:c25:c25:94de:24b7
1852c19:dd:d9:dd:c25:c25:94de:24b8/1282c19:dd:d9:dd:c25:c25:94de:24b8
1862c19:dd:d9:dd:c25:c25:94de:24b9/1282c19:dd:d9:dd:c25:c25:94de:24b9
1872c19:dd:d9:dd:c25:c25:94de:24ba/1282c19:dd:d9:dd:c25:c25:94de:24ba
1882c19:dd:d9:dd:c25:c25:94de:24bb/1282c19:dd:d9:dd:c25:c25:94de:24bb
1892c19:dd:d9:dd:c25:c25:94de:24bc/1282c19:dd:d9:dd:c25:c25:94de:24bc
1902c19:dd:d9:dd:c25:c25:94de:24bd/1282c19:dd:d9:dd:c25:c25:94de:24bd
1912c19:dd:d9:dd:c25:c25:94de:24be/1282c19:dd:d9:dd:c25:c25:94de:24be
1922c19:dd:d9:dd:c25:c25:94de:24bf/1282c19:dd:d9:dd:c25:c25:94de:24bf
1932c19:dd:d9:dd:c25:c25:94de:24c0/1282c19:dd:d9:dd:c25:c25:94de:24c0
1942c19:dd:d9:dd:c25:c25:94de:24c1/1282c19:dd:d9:dd:c25:c25:94de:24c1
1952c19:dd:d9:dd:c25:c25:94de:24c2/1282c19:dd:d9:dd:c25:c25:94de:24c2
1962c19:dd:d9:dd:c25:c25:94de:24c3/1282c19:dd:d9:dd:c25:c25:94de:24c3
1972c19:dd:d9:dd:c25:c25:94de:24c4/1282c19:dd:d9:dd:c25:c25:94de:24c4
1982c19:dd:d9:dd:c25:c25:94de:24c5/1282c19:dd:d9:dd:c25:c25:94de:24c5
1992c19:dd:d9:dd:c25:c25:94de:24c6/1282c19:dd:d9:dd:c25:c25:94de:24c6
2002c19:dd:d9:dd:c25:c25:94de:24c7/1282c19:dd:d9:dd:c25:c25:94de:24c7
2012c19:dd:d9:dd:c25:c25:94de:24c8/1282c19:dd:d9:dd:c25:c25:94de:24c8
2022c19:dd:d9:dd:c25:c25:94de:24c9/1282c19:dd:d9:dd:c25:c25:94de:24c9
2032c19:dd:d9:dd:c25:c25:94de:24ca/1282c19:dd:d9:dd:c25:c25:94de:24ca
2042c19:dd:d9:dd:c25:c25:94de:24cb/1282c19:dd:d9:dd:c25:c25:94de:24cb
2052c19:dd:d9:dd:c25:c25:94de:24cc/1282c19:dd:d9:dd:c25:c25:94de:24cc
2062c19:dd:d9:dd:c25:c25:94de:24cd/1282c19:dd:d9:dd:c25:c25:94de:24cd
2072c19:dd:d9:dd:c25:c25:94de:24ce/1282c19:dd:d9:dd:c25:c25:94de:24ce
2082c19:dd:d9:dd:c25:c25:94de:24cf/1282c19:dd:d9:dd:c25:c25:94de:24cf
2092c19:dd:d9:dd:c25:c25:94de:24d0/1282c19:dd:d9:dd:c25:c25:94de:24d0
2102c19:dd:d9:dd:c25:c25:94de:24d1/1282c19:dd:d9:dd:c25:c25:94de:24d1
2112c19:dd:d9:dd:c25:c25:94de:24d2/1282c19:dd:d9:dd:c25:c25:94de:24d2
2122c19:dd:d9:dd:c25:c25:94de:24d3/1282c19:dd:d9:dd:c25:c25:94de:24d3
2132c19:dd:d9:dd:c25:c25:94de:24d4/1282c19:dd:d9:dd:c25:c25:94de:24d4
2142c19:dd:d9:dd:c25:c25:94de:24d5/1282c19:dd:d9:dd:c25:c25:94de:24d5
2152c19:dd:d9:dd:c25:c25:94de:24d6/1282c19:dd:d9:dd:c25:c25:94de:24d6
2162c19:dd:d9:dd:c25:c25:94de:24d7/1282c19:dd:d9:dd:c25:c25:94de:24d7
2172c19:dd:d9:dd:c25:c25:94de:24d8/1282c19:dd:d9:dd:c25:c25:94de:24d8
2182c19:dd:d9:dd:c25:c25:94de:24d9/1282c19:dd:d9:dd:c25:c25:94de:24d9
2192c19:dd:d9:dd:c25:c25:94de:24da/1282c19:dd:d9:dd:c25:c25:94de:24da
2202c19:dd:d9:dd:c25:c25:94de:24db/1282c19:dd:d9:dd:c25:c25:94de:24db
2212c19:dd:d9:dd:c25:c25:94de:24dc/1282c19:dd:d9:dd:c25:c25:94de:24dc
2222c19:dd:d9:dd:c25:c25:94de:24dd/1282c19:dd:d9:dd:c25:c25:94de:24dd
2232c19:dd:d9:dd:c25:c25:94de:24de/1282c19:dd:d9:dd:c25:c25:94de:24de
2242c19:dd:d9:dd:c25:c25:94de:24df/1282c19:dd:d9:dd:c25:c25:94de:24df
2252c19:dd:d9:dd:c25:c25:94de:24e0/1282c19:dd:d9:dd:c25:c25:94de:24e0
2262c19:dd:d9:dd:c25:c25:94de:24e1/1282c19:dd:d9:dd:c25:c25:94de:24e1
2272c19:dd:d9:dd:c25:c25:94de:24e2/1282c19:dd:d9:dd:c25:c25:94de:24e2
2282c19:dd:d9:dd:c25:c25:94de:24e3/1282c19:dd:d9:dd:c25:c25:94de:24e3
2292c19:dd:d9:dd:c25:c25:94de:24e4/1282c19:dd:d9:dd:c25:c25:94de:24e4
2302c19:dd:d9:dd:c25:c25:94de:24e5/1282c19:dd:d9:dd:c25:c25:94de:24e5
2312c19:dd:d9:dd:c25:c25:94de:24e6/1282c19:dd:d9:dd:c25:c25:94de:24e6
2322c19:dd:d9:dd:c25:c25:94de:24e7/1282c19:dd:d9:dd:c25:c25:94de:24e7
2332c19:dd:d9:dd:c25:c25:94de:24e8/1282c19:dd:d9:dd:c25:c25:94de:24e8
2342c19:dd:d9:dd:c25:c25:94de:24e9/1282c19:dd:d9:dd:c25:c25:94de:24e9
2352c19:dd:d9:dd:c25:c25:94de:24ea/1282c19:dd:d9:dd:c25:c25:94de:24ea
2362c19:dd:d9:dd:c25:c25:94de:24eb/1282c19:dd:d9:dd:c25:c25:94de:24eb
2372c19:dd:d9:dd:c25:c25:94de:24ec/1282c19:dd:d9:dd:c25:c25:94de:24ec
2382c19:dd:d9:dd:c25:c25:94de:24ed/1282c19:dd:d9:dd:c25:c25:94de:24ed
2392c19:dd:d9:dd:c25:c25:94de:24ee/1282c19:dd:d9:dd:c25:c25:94de:24ee
2402c19:dd:d9:dd:c25:c25:94de:24ef/1282c19:dd:d9:dd:c25:c25:94de:24ef
2412c19:dd:d9:dd:c25:c25:94de:24f0/1282c19:dd:d9:dd:c25:c25:94de:24f0
2422c19:dd:d9:dd:c25:c25:94de:24f1/1282c19:dd:d9:dd:c25:c25:94de:24f1
2432c19:dd:d9:dd:c25:c25:94de:24f2/1282c19:dd:d9:dd:c25:c25:94de:24f2
2442c19:dd:d9:dd:c25:c25:94de:24f3/1282c19:dd:d9:dd:c25:c25:94de:24f3
2452c19:dd:d9:dd:c25:c25:94de:24f4/1282c19:dd:d9:dd:c25:c25:94de:24f4
2462c19:dd:d9:dd:c25:c25:94de:24f5/1282c19:dd:d9:dd:c25:c25:94de:24f5
2472c19:dd:d9:dd:c25:c25:94de:24f6/1282c19:dd:d9:dd:c25:c25:94de:24f6
2482c19:dd:d9:dd:c25:c25:94de:24f7/1282c19:dd:d9:dd:c25:c25:94de:24f7
2492c19:dd:d9:dd:c25:c25:94de:24f8/1282c19:dd:d9:dd:c25:c25:94de:24f8
2502c19:dd:d9:dd:c25:c25:94de:24f9/1282c19:dd:d9:dd:c25:c25:94de:24f9
2512c19:dd:d9:dd:c25:c25:94de:24fa/1282c19:dd:d9:dd:c25:c25:94de:24fa
2522c19:dd:d9:dd:c25:c25:94de:24fb/1282c19:dd:d9:dd:c25:c25:94de:24fb
2532c19:dd:d9:dd:c25:c25:94de:24fc/1282c19:dd:d9:dd:c25:c25:94de:24fc
2542c19:dd:d9:dd:c25:c25:94de:24fd/1282c19:dd:d9:dd:c25:c25:94de:24fd
2552c19:dd:d9:dd:c25:c25:94de:24fe/1282c19:dd:d9:dd:c25:c25:94de:24fe
2562c19:dd:d9:dd:c25:c25:94de:24ff/1282c19:dd:d9:dd:c25:c25:94de:24ff

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.