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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:2300/120
First address
2c19:dd:d9:dd:c25:c25:94de:2300
Last address
2c19:dd:d9:dd:c25:c25:94de:23ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:00d9:00dd:0c25:0c25:94de:2300
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
3.2.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:2300/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:d9:dd:c25:c25:94de:2300/1282c19:dd:d9:dd:c25:c25:94de:2300
22c19:dd:d9:dd:c25:c25:94de:2301/1282c19:dd:d9:dd:c25:c25:94de:2301
32c19:dd:d9:dd:c25:c25:94de:2302/1282c19:dd:d9:dd:c25:c25:94de:2302
42c19:dd:d9:dd:c25:c25:94de:2303/1282c19:dd:d9:dd:c25:c25:94de:2303
52c19:dd:d9:dd:c25:c25:94de:2304/1282c19:dd:d9:dd:c25:c25:94de:2304
62c19:dd:d9:dd:c25:c25:94de:2305/1282c19:dd:d9:dd:c25:c25:94de:2305
72c19:dd:d9:dd:c25:c25:94de:2306/1282c19:dd:d9:dd:c25:c25:94de:2306
82c19:dd:d9:dd:c25:c25:94de:2307/1282c19:dd:d9:dd:c25:c25:94de:2307
92c19:dd:d9:dd:c25:c25:94de:2308/1282c19:dd:d9:dd:c25:c25:94de:2308
102c19:dd:d9:dd:c25:c25:94de:2309/1282c19:dd:d9:dd:c25:c25:94de:2309
112c19:dd:d9:dd:c25:c25:94de:230a/1282c19:dd:d9:dd:c25:c25:94de:230a
122c19:dd:d9:dd:c25:c25:94de:230b/1282c19:dd:d9:dd:c25:c25:94de:230b
132c19:dd:d9:dd:c25:c25:94de:230c/1282c19:dd:d9:dd:c25:c25:94de:230c
142c19:dd:d9:dd:c25:c25:94de:230d/1282c19:dd:d9:dd:c25:c25:94de:230d
152c19:dd:d9:dd:c25:c25:94de:230e/1282c19:dd:d9:dd:c25:c25:94de:230e
162c19:dd:d9:dd:c25:c25:94de:230f/1282c19:dd:d9:dd:c25:c25:94de:230f
172c19:dd:d9:dd:c25:c25:94de:2310/1282c19:dd:d9:dd:c25:c25:94de:2310
182c19:dd:d9:dd:c25:c25:94de:2311/1282c19:dd:d9:dd:c25:c25:94de:2311
192c19:dd:d9:dd:c25:c25:94de:2312/1282c19:dd:d9:dd:c25:c25:94de:2312
202c19:dd:d9:dd:c25:c25:94de:2313/1282c19:dd:d9:dd:c25:c25:94de:2313
212c19:dd:d9:dd:c25:c25:94de:2314/1282c19:dd:d9:dd:c25:c25:94de:2314
222c19:dd:d9:dd:c25:c25:94de:2315/1282c19:dd:d9:dd:c25:c25:94de:2315
232c19:dd:d9:dd:c25:c25:94de:2316/1282c19:dd:d9:dd:c25:c25:94de:2316
242c19:dd:d9:dd:c25:c25:94de:2317/1282c19:dd:d9:dd:c25:c25:94de:2317
252c19:dd:d9:dd:c25:c25:94de:2318/1282c19:dd:d9:dd:c25:c25:94de:2318
262c19:dd:d9:dd:c25:c25:94de:2319/1282c19:dd:d9:dd:c25:c25:94de:2319
272c19:dd:d9:dd:c25:c25:94de:231a/1282c19:dd:d9:dd:c25:c25:94de:231a
282c19:dd:d9:dd:c25:c25:94de:231b/1282c19:dd:d9:dd:c25:c25:94de:231b
292c19:dd:d9:dd:c25:c25:94de:231c/1282c19:dd:d9:dd:c25:c25:94de:231c
302c19:dd:d9:dd:c25:c25:94de:231d/1282c19:dd:d9:dd:c25:c25:94de:231d
312c19:dd:d9:dd:c25:c25:94de:231e/1282c19:dd:d9:dd:c25:c25:94de:231e
322c19:dd:d9:dd:c25:c25:94de:231f/1282c19:dd:d9:dd:c25:c25:94de:231f
332c19:dd:d9:dd:c25:c25:94de:2320/1282c19:dd:d9:dd:c25:c25:94de:2320
342c19:dd:d9:dd:c25:c25:94de:2321/1282c19:dd:d9:dd:c25:c25:94de:2321
352c19:dd:d9:dd:c25:c25:94de:2322/1282c19:dd:d9:dd:c25:c25:94de:2322
362c19:dd:d9:dd:c25:c25:94de:2323/1282c19:dd:d9:dd:c25:c25:94de:2323
372c19:dd:d9:dd:c25:c25:94de:2324/1282c19:dd:d9:dd:c25:c25:94de:2324
382c19:dd:d9:dd:c25:c25:94de:2325/1282c19:dd:d9:dd:c25:c25:94de:2325
392c19:dd:d9:dd:c25:c25:94de:2326/1282c19:dd:d9:dd:c25:c25:94de:2326
402c19:dd:d9:dd:c25:c25:94de:2327/1282c19:dd:d9:dd:c25:c25:94de:2327
412c19:dd:d9:dd:c25:c25:94de:2328/1282c19:dd:d9:dd:c25:c25:94de:2328
422c19:dd:d9:dd:c25:c25:94de:2329/1282c19:dd:d9:dd:c25:c25:94de:2329
432c19:dd:d9:dd:c25:c25:94de:232a/1282c19:dd:d9:dd:c25:c25:94de:232a
442c19:dd:d9:dd:c25:c25:94de:232b/1282c19:dd:d9:dd:c25:c25:94de:232b
452c19:dd:d9:dd:c25:c25:94de:232c/1282c19:dd:d9:dd:c25:c25:94de:232c
462c19:dd:d9:dd:c25:c25:94de:232d/1282c19:dd:d9:dd:c25:c25:94de:232d
472c19:dd:d9:dd:c25:c25:94de:232e/1282c19:dd:d9:dd:c25:c25:94de:232e
482c19:dd:d9:dd:c25:c25:94de:232f/1282c19:dd:d9:dd:c25:c25:94de:232f
492c19:dd:d9:dd:c25:c25:94de:2330/1282c19:dd:d9:dd:c25:c25:94de:2330
502c19:dd:d9:dd:c25:c25:94de:2331/1282c19:dd:d9:dd:c25:c25:94de:2331
512c19:dd:d9:dd:c25:c25:94de:2332/1282c19:dd:d9:dd:c25:c25:94de:2332
522c19:dd:d9:dd:c25:c25:94de:2333/1282c19:dd:d9:dd:c25:c25:94de:2333
532c19:dd:d9:dd:c25:c25:94de:2334/1282c19:dd:d9:dd:c25:c25:94de:2334
542c19:dd:d9:dd:c25:c25:94de:2335/1282c19:dd:d9:dd:c25:c25:94de:2335
552c19:dd:d9:dd:c25:c25:94de:2336/1282c19:dd:d9:dd:c25:c25:94de:2336
562c19:dd:d9:dd:c25:c25:94de:2337/1282c19:dd:d9:dd:c25:c25:94de:2337
572c19:dd:d9:dd:c25:c25:94de:2338/1282c19:dd:d9:dd:c25:c25:94de:2338
582c19:dd:d9:dd:c25:c25:94de:2339/1282c19:dd:d9:dd:c25:c25:94de:2339
592c19:dd:d9:dd:c25:c25:94de:233a/1282c19:dd:d9:dd:c25:c25:94de:233a
602c19:dd:d9:dd:c25:c25:94de:233b/1282c19:dd:d9:dd:c25:c25:94de:233b
612c19:dd:d9:dd:c25:c25:94de:233c/1282c19:dd:d9:dd:c25:c25:94de:233c
622c19:dd:d9:dd:c25:c25:94de:233d/1282c19:dd:d9:dd:c25:c25:94de:233d
632c19:dd:d9:dd:c25:c25:94de:233e/1282c19:dd:d9:dd:c25:c25:94de:233e
642c19:dd:d9:dd:c25:c25:94de:233f/1282c19:dd:d9:dd:c25:c25:94de:233f
652c19:dd:d9:dd:c25:c25:94de:2340/1282c19:dd:d9:dd:c25:c25:94de:2340
662c19:dd:d9:dd:c25:c25:94de:2341/1282c19:dd:d9:dd:c25:c25:94de:2341
672c19:dd:d9:dd:c25:c25:94de:2342/1282c19:dd:d9:dd:c25:c25:94de:2342
682c19:dd:d9:dd:c25:c25:94de:2343/1282c19:dd:d9:dd:c25:c25:94de:2343
692c19:dd:d9:dd:c25:c25:94de:2344/1282c19:dd:d9:dd:c25:c25:94de:2344
702c19:dd:d9:dd:c25:c25:94de:2345/1282c19:dd:d9:dd:c25:c25:94de:2345
712c19:dd:d9:dd:c25:c25:94de:2346/1282c19:dd:d9:dd:c25:c25:94de:2346
722c19:dd:d9:dd:c25:c25:94de:2347/1282c19:dd:d9:dd:c25:c25:94de:2347
732c19:dd:d9:dd:c25:c25:94de:2348/1282c19:dd:d9:dd:c25:c25:94de:2348
742c19:dd:d9:dd:c25:c25:94de:2349/1282c19:dd:d9:dd:c25:c25:94de:2349
752c19:dd:d9:dd:c25:c25:94de:234a/1282c19:dd:d9:dd:c25:c25:94de:234a
762c19:dd:d9:dd:c25:c25:94de:234b/1282c19:dd:d9:dd:c25:c25:94de:234b
772c19:dd:d9:dd:c25:c25:94de:234c/1282c19:dd:d9:dd:c25:c25:94de:234c
782c19:dd:d9:dd:c25:c25:94de:234d/1282c19:dd:d9:dd:c25:c25:94de:234d
792c19:dd:d9:dd:c25:c25:94de:234e/1282c19:dd:d9:dd:c25:c25:94de:234e
802c19:dd:d9:dd:c25:c25:94de:234f/1282c19:dd:d9:dd:c25:c25:94de:234f
812c19:dd:d9:dd:c25:c25:94de:2350/1282c19:dd:d9:dd:c25:c25:94de:2350
822c19:dd:d9:dd:c25:c25:94de:2351/1282c19:dd:d9:dd:c25:c25:94de:2351
832c19:dd:d9:dd:c25:c25:94de:2352/1282c19:dd:d9:dd:c25:c25:94de:2352
842c19:dd:d9:dd:c25:c25:94de:2353/1282c19:dd:d9:dd:c25:c25:94de:2353
852c19:dd:d9:dd:c25:c25:94de:2354/1282c19:dd:d9:dd:c25:c25:94de:2354
862c19:dd:d9:dd:c25:c25:94de:2355/1282c19:dd:d9:dd:c25:c25:94de:2355
872c19:dd:d9:dd:c25:c25:94de:2356/1282c19:dd:d9:dd:c25:c25:94de:2356
882c19:dd:d9:dd:c25:c25:94de:2357/1282c19:dd:d9:dd:c25:c25:94de:2357
892c19:dd:d9:dd:c25:c25:94de:2358/1282c19:dd:d9:dd:c25:c25:94de:2358
902c19:dd:d9:dd:c25:c25:94de:2359/1282c19:dd:d9:dd:c25:c25:94de:2359
912c19:dd:d9:dd:c25:c25:94de:235a/1282c19:dd:d9:dd:c25:c25:94de:235a
922c19:dd:d9:dd:c25:c25:94de:235b/1282c19:dd:d9:dd:c25:c25:94de:235b
932c19:dd:d9:dd:c25:c25:94de:235c/1282c19:dd:d9:dd:c25:c25:94de:235c
942c19:dd:d9:dd:c25:c25:94de:235d/1282c19:dd:d9:dd:c25:c25:94de:235d
952c19:dd:d9:dd:c25:c25:94de:235e/1282c19:dd:d9:dd:c25:c25:94de:235e
962c19:dd:d9:dd:c25:c25:94de:235f/1282c19:dd:d9:dd:c25:c25:94de:235f
972c19:dd:d9:dd:c25:c25:94de:2360/1282c19:dd:d9:dd:c25:c25:94de:2360
982c19:dd:d9:dd:c25:c25:94de:2361/1282c19:dd:d9:dd:c25:c25:94de:2361
992c19:dd:d9:dd:c25:c25:94de:2362/1282c19:dd:d9:dd:c25:c25:94de:2362
1002c19:dd:d9:dd:c25:c25:94de:2363/1282c19:dd:d9:dd:c25:c25:94de:2363
1012c19:dd:d9:dd:c25:c25:94de:2364/1282c19:dd:d9:dd:c25:c25:94de:2364
1022c19:dd:d9:dd:c25:c25:94de:2365/1282c19:dd:d9:dd:c25:c25:94de:2365
1032c19:dd:d9:dd:c25:c25:94de:2366/1282c19:dd:d9:dd:c25:c25:94de:2366
1042c19:dd:d9:dd:c25:c25:94de:2367/1282c19:dd:d9:dd:c25:c25:94de:2367
1052c19:dd:d9:dd:c25:c25:94de:2368/1282c19:dd:d9:dd:c25:c25:94de:2368
1062c19:dd:d9:dd:c25:c25:94de:2369/1282c19:dd:d9:dd:c25:c25:94de:2369
1072c19:dd:d9:dd:c25:c25:94de:236a/1282c19:dd:d9:dd:c25:c25:94de:236a
1082c19:dd:d9:dd:c25:c25:94de:236b/1282c19:dd:d9:dd:c25:c25:94de:236b
1092c19:dd:d9:dd:c25:c25:94de:236c/1282c19:dd:d9:dd:c25:c25:94de:236c
1102c19:dd:d9:dd:c25:c25:94de:236d/1282c19:dd:d9:dd:c25:c25:94de:236d
1112c19:dd:d9:dd:c25:c25:94de:236e/1282c19:dd:d9:dd:c25:c25:94de:236e
1122c19:dd:d9:dd:c25:c25:94de:236f/1282c19:dd:d9:dd:c25:c25:94de:236f
1132c19:dd:d9:dd:c25:c25:94de:2370/1282c19:dd:d9:dd:c25:c25:94de:2370
1142c19:dd:d9:dd:c25:c25:94de:2371/1282c19:dd:d9:dd:c25:c25:94de:2371
1152c19:dd:d9:dd:c25:c25:94de:2372/1282c19:dd:d9:dd:c25:c25:94de:2372
1162c19:dd:d9:dd:c25:c25:94de:2373/1282c19:dd:d9:dd:c25:c25:94de:2373
1172c19:dd:d9:dd:c25:c25:94de:2374/1282c19:dd:d9:dd:c25:c25:94de:2374
1182c19:dd:d9:dd:c25:c25:94de:2375/1282c19:dd:d9:dd:c25:c25:94de:2375
1192c19:dd:d9:dd:c25:c25:94de:2376/1282c19:dd:d9:dd:c25:c25:94de:2376
1202c19:dd:d9:dd:c25:c25:94de:2377/1282c19:dd:d9:dd:c25:c25:94de:2377
1212c19:dd:d9:dd:c25:c25:94de:2378/1282c19:dd:d9:dd:c25:c25:94de:2378
1222c19:dd:d9:dd:c25:c25:94de:2379/1282c19:dd:d9:dd:c25:c25:94de:2379
1232c19:dd:d9:dd:c25:c25:94de:237a/1282c19:dd:d9:dd:c25:c25:94de:237a
1242c19:dd:d9:dd:c25:c25:94de:237b/1282c19:dd:d9:dd:c25:c25:94de:237b
1252c19:dd:d9:dd:c25:c25:94de:237c/1282c19:dd:d9:dd:c25:c25:94de:237c
1262c19:dd:d9:dd:c25:c25:94de:237d/1282c19:dd:d9:dd:c25:c25:94de:237d
1272c19:dd:d9:dd:c25:c25:94de:237e/1282c19:dd:d9:dd:c25:c25:94de:237e
1282c19:dd:d9:dd:c25:c25:94de:237f/1282c19:dd:d9:dd:c25:c25:94de:237f
1292c19:dd:d9:dd:c25:c25:94de:2380/1282c19:dd:d9:dd:c25:c25:94de:2380
1302c19:dd:d9:dd:c25:c25:94de:2381/1282c19:dd:d9:dd:c25:c25:94de:2381
1312c19:dd:d9:dd:c25:c25:94de:2382/1282c19:dd:d9:dd:c25:c25:94de:2382
1322c19:dd:d9:dd:c25:c25:94de:2383/1282c19:dd:d9:dd:c25:c25:94de:2383
1332c19:dd:d9:dd:c25:c25:94de:2384/1282c19:dd:d9:dd:c25:c25:94de:2384
1342c19:dd:d9:dd:c25:c25:94de:2385/1282c19:dd:d9:dd:c25:c25:94de:2385
1352c19:dd:d9:dd:c25:c25:94de:2386/1282c19:dd:d9:dd:c25:c25:94de:2386
1362c19:dd:d9:dd:c25:c25:94de:2387/1282c19:dd:d9:dd:c25:c25:94de:2387
1372c19:dd:d9:dd:c25:c25:94de:2388/1282c19:dd:d9:dd:c25:c25:94de:2388
1382c19:dd:d9:dd:c25:c25:94de:2389/1282c19:dd:d9:dd:c25:c25:94de:2389
1392c19:dd:d9:dd:c25:c25:94de:238a/1282c19:dd:d9:dd:c25:c25:94de:238a
1402c19:dd:d9:dd:c25:c25:94de:238b/1282c19:dd:d9:dd:c25:c25:94de:238b
1412c19:dd:d9:dd:c25:c25:94de:238c/1282c19:dd:d9:dd:c25:c25:94de:238c
1422c19:dd:d9:dd:c25:c25:94de:238d/1282c19:dd:d9:dd:c25:c25:94de:238d
1432c19:dd:d9:dd:c25:c25:94de:238e/1282c19:dd:d9:dd:c25:c25:94de:238e
1442c19:dd:d9:dd:c25:c25:94de:238f/1282c19:dd:d9:dd:c25:c25:94de:238f
1452c19:dd:d9:dd:c25:c25:94de:2390/1282c19:dd:d9:dd:c25:c25:94de:2390
1462c19:dd:d9:dd:c25:c25:94de:2391/1282c19:dd:d9:dd:c25:c25:94de:2391
1472c19:dd:d9:dd:c25:c25:94de:2392/1282c19:dd:d9:dd:c25:c25:94de:2392
1482c19:dd:d9:dd:c25:c25:94de:2393/1282c19:dd:d9:dd:c25:c25:94de:2393
1492c19:dd:d9:dd:c25:c25:94de:2394/1282c19:dd:d9:dd:c25:c25:94de:2394
1502c19:dd:d9:dd:c25:c25:94de:2395/1282c19:dd:d9:dd:c25:c25:94de:2395
1512c19:dd:d9:dd:c25:c25:94de:2396/1282c19:dd:d9:dd:c25:c25:94de:2396
1522c19:dd:d9:dd:c25:c25:94de:2397/1282c19:dd:d9:dd:c25:c25:94de:2397
1532c19:dd:d9:dd:c25:c25:94de:2398/1282c19:dd:d9:dd:c25:c25:94de:2398
1542c19:dd:d9:dd:c25:c25:94de:2399/1282c19:dd:d9:dd:c25:c25:94de:2399
1552c19:dd:d9:dd:c25:c25:94de:239a/1282c19:dd:d9:dd:c25:c25:94de:239a
1562c19:dd:d9:dd:c25:c25:94de:239b/1282c19:dd:d9:dd:c25:c25:94de:239b
1572c19:dd:d9:dd:c25:c25:94de:239c/1282c19:dd:d9:dd:c25:c25:94de:239c
1582c19:dd:d9:dd:c25:c25:94de:239d/1282c19:dd:d9:dd:c25:c25:94de:239d
1592c19:dd:d9:dd:c25:c25:94de:239e/1282c19:dd:d9:dd:c25:c25:94de:239e
1602c19:dd:d9:dd:c25:c25:94de:239f/1282c19:dd:d9:dd:c25:c25:94de:239f
1612c19:dd:d9:dd:c25:c25:94de:23a0/1282c19:dd:d9:dd:c25:c25:94de:23a0
1622c19:dd:d9:dd:c25:c25:94de:23a1/1282c19:dd:d9:dd:c25:c25:94de:23a1
1632c19:dd:d9:dd:c25:c25:94de:23a2/1282c19:dd:d9:dd:c25:c25:94de:23a2
1642c19:dd:d9:dd:c25:c25:94de:23a3/1282c19:dd:d9:dd:c25:c25:94de:23a3
1652c19:dd:d9:dd:c25:c25:94de:23a4/1282c19:dd:d9:dd:c25:c25:94de:23a4
1662c19:dd:d9:dd:c25:c25:94de:23a5/1282c19:dd:d9:dd:c25:c25:94de:23a5
1672c19:dd:d9:dd:c25:c25:94de:23a6/1282c19:dd:d9:dd:c25:c25:94de:23a6
1682c19:dd:d9:dd:c25:c25:94de:23a7/1282c19:dd:d9:dd:c25:c25:94de:23a7
1692c19:dd:d9:dd:c25:c25:94de:23a8/1282c19:dd:d9:dd:c25:c25:94de:23a8
1702c19:dd:d9:dd:c25:c25:94de:23a9/1282c19:dd:d9:dd:c25:c25:94de:23a9
1712c19:dd:d9:dd:c25:c25:94de:23aa/1282c19:dd:d9:dd:c25:c25:94de:23aa
1722c19:dd:d9:dd:c25:c25:94de:23ab/1282c19:dd:d9:dd:c25:c25:94de:23ab
1732c19:dd:d9:dd:c25:c25:94de:23ac/1282c19:dd:d9:dd:c25:c25:94de:23ac
1742c19:dd:d9:dd:c25:c25:94de:23ad/1282c19:dd:d9:dd:c25:c25:94de:23ad
1752c19:dd:d9:dd:c25:c25:94de:23ae/1282c19:dd:d9:dd:c25:c25:94de:23ae
1762c19:dd:d9:dd:c25:c25:94de:23af/1282c19:dd:d9:dd:c25:c25:94de:23af
1772c19:dd:d9:dd:c25:c25:94de:23b0/1282c19:dd:d9:dd:c25:c25:94de:23b0
1782c19:dd:d9:dd:c25:c25:94de:23b1/1282c19:dd:d9:dd:c25:c25:94de:23b1
1792c19:dd:d9:dd:c25:c25:94de:23b2/1282c19:dd:d9:dd:c25:c25:94de:23b2
1802c19:dd:d9:dd:c25:c25:94de:23b3/1282c19:dd:d9:dd:c25:c25:94de:23b3
1812c19:dd:d9:dd:c25:c25:94de:23b4/1282c19:dd:d9:dd:c25:c25:94de:23b4
1822c19:dd:d9:dd:c25:c25:94de:23b5/1282c19:dd:d9:dd:c25:c25:94de:23b5
1832c19:dd:d9:dd:c25:c25:94de:23b6/1282c19:dd:d9:dd:c25:c25:94de:23b6
1842c19:dd:d9:dd:c25:c25:94de:23b7/1282c19:dd:d9:dd:c25:c25:94de:23b7
1852c19:dd:d9:dd:c25:c25:94de:23b8/1282c19:dd:d9:dd:c25:c25:94de:23b8
1862c19:dd:d9:dd:c25:c25:94de:23b9/1282c19:dd:d9:dd:c25:c25:94de:23b9
1872c19:dd:d9:dd:c25:c25:94de:23ba/1282c19:dd:d9:dd:c25:c25:94de:23ba
1882c19:dd:d9:dd:c25:c25:94de:23bb/1282c19:dd:d9:dd:c25:c25:94de:23bb
1892c19:dd:d9:dd:c25:c25:94de:23bc/1282c19:dd:d9:dd:c25:c25:94de:23bc
1902c19:dd:d9:dd:c25:c25:94de:23bd/1282c19:dd:d9:dd:c25:c25:94de:23bd
1912c19:dd:d9:dd:c25:c25:94de:23be/1282c19:dd:d9:dd:c25:c25:94de:23be
1922c19:dd:d9:dd:c25:c25:94de:23bf/1282c19:dd:d9:dd:c25:c25:94de:23bf
1932c19:dd:d9:dd:c25:c25:94de:23c0/1282c19:dd:d9:dd:c25:c25:94de:23c0
1942c19:dd:d9:dd:c25:c25:94de:23c1/1282c19:dd:d9:dd:c25:c25:94de:23c1
1952c19:dd:d9:dd:c25:c25:94de:23c2/1282c19:dd:d9:dd:c25:c25:94de:23c2
1962c19:dd:d9:dd:c25:c25:94de:23c3/1282c19:dd:d9:dd:c25:c25:94de:23c3
1972c19:dd:d9:dd:c25:c25:94de:23c4/1282c19:dd:d9:dd:c25:c25:94de:23c4
1982c19:dd:d9:dd:c25:c25:94de:23c5/1282c19:dd:d9:dd:c25:c25:94de:23c5
1992c19:dd:d9:dd:c25:c25:94de:23c6/1282c19:dd:d9:dd:c25:c25:94de:23c6
2002c19:dd:d9:dd:c25:c25:94de:23c7/1282c19:dd:d9:dd:c25:c25:94de:23c7
2012c19:dd:d9:dd:c25:c25:94de:23c8/1282c19:dd:d9:dd:c25:c25:94de:23c8
2022c19:dd:d9:dd:c25:c25:94de:23c9/1282c19:dd:d9:dd:c25:c25:94de:23c9
2032c19:dd:d9:dd:c25:c25:94de:23ca/1282c19:dd:d9:dd:c25:c25:94de:23ca
2042c19:dd:d9:dd:c25:c25:94de:23cb/1282c19:dd:d9:dd:c25:c25:94de:23cb
2052c19:dd:d9:dd:c25:c25:94de:23cc/1282c19:dd:d9:dd:c25:c25:94de:23cc
2062c19:dd:d9:dd:c25:c25:94de:23cd/1282c19:dd:d9:dd:c25:c25:94de:23cd
2072c19:dd:d9:dd:c25:c25:94de:23ce/1282c19:dd:d9:dd:c25:c25:94de:23ce
2082c19:dd:d9:dd:c25:c25:94de:23cf/1282c19:dd:d9:dd:c25:c25:94de:23cf
2092c19:dd:d9:dd:c25:c25:94de:23d0/1282c19:dd:d9:dd:c25:c25:94de:23d0
2102c19:dd:d9:dd:c25:c25:94de:23d1/1282c19:dd:d9:dd:c25:c25:94de:23d1
2112c19:dd:d9:dd:c25:c25:94de:23d2/1282c19:dd:d9:dd:c25:c25:94de:23d2
2122c19:dd:d9:dd:c25:c25:94de:23d3/1282c19:dd:d9:dd:c25:c25:94de:23d3
2132c19:dd:d9:dd:c25:c25:94de:23d4/1282c19:dd:d9:dd:c25:c25:94de:23d4
2142c19:dd:d9:dd:c25:c25:94de:23d5/1282c19:dd:d9:dd:c25:c25:94de:23d5
2152c19:dd:d9:dd:c25:c25:94de:23d6/1282c19:dd:d9:dd:c25:c25:94de:23d6
2162c19:dd:d9:dd:c25:c25:94de:23d7/1282c19:dd:d9:dd:c25:c25:94de:23d7
2172c19:dd:d9:dd:c25:c25:94de:23d8/1282c19:dd:d9:dd:c25:c25:94de:23d8
2182c19:dd:d9:dd:c25:c25:94de:23d9/1282c19:dd:d9:dd:c25:c25:94de:23d9
2192c19:dd:d9:dd:c25:c25:94de:23da/1282c19:dd:d9:dd:c25:c25:94de:23da
2202c19:dd:d9:dd:c25:c25:94de:23db/1282c19:dd:d9:dd:c25:c25:94de:23db
2212c19:dd:d9:dd:c25:c25:94de:23dc/1282c19:dd:d9:dd:c25:c25:94de:23dc
2222c19:dd:d9:dd:c25:c25:94de:23dd/1282c19:dd:d9:dd:c25:c25:94de:23dd
2232c19:dd:d9:dd:c25:c25:94de:23de/1282c19:dd:d9:dd:c25:c25:94de:23de
2242c19:dd:d9:dd:c25:c25:94de:23df/1282c19:dd:d9:dd:c25:c25:94de:23df
2252c19:dd:d9:dd:c25:c25:94de:23e0/1282c19:dd:d9:dd:c25:c25:94de:23e0
2262c19:dd:d9:dd:c25:c25:94de:23e1/1282c19:dd:d9:dd:c25:c25:94de:23e1
2272c19:dd:d9:dd:c25:c25:94de:23e2/1282c19:dd:d9:dd:c25:c25:94de:23e2
2282c19:dd:d9:dd:c25:c25:94de:23e3/1282c19:dd:d9:dd:c25:c25:94de:23e3
2292c19:dd:d9:dd:c25:c25:94de:23e4/1282c19:dd:d9:dd:c25:c25:94de:23e4
2302c19:dd:d9:dd:c25:c25:94de:23e5/1282c19:dd:d9:dd:c25:c25:94de:23e5
2312c19:dd:d9:dd:c25:c25:94de:23e6/1282c19:dd:d9:dd:c25:c25:94de:23e6
2322c19:dd:d9:dd:c25:c25:94de:23e7/1282c19:dd:d9:dd:c25:c25:94de:23e7
2332c19:dd:d9:dd:c25:c25:94de:23e8/1282c19:dd:d9:dd:c25:c25:94de:23e8
2342c19:dd:d9:dd:c25:c25:94de:23e9/1282c19:dd:d9:dd:c25:c25:94de:23e9
2352c19:dd:d9:dd:c25:c25:94de:23ea/1282c19:dd:d9:dd:c25:c25:94de:23ea
2362c19:dd:d9:dd:c25:c25:94de:23eb/1282c19:dd:d9:dd:c25:c25:94de:23eb
2372c19:dd:d9:dd:c25:c25:94de:23ec/1282c19:dd:d9:dd:c25:c25:94de:23ec
2382c19:dd:d9:dd:c25:c25:94de:23ed/1282c19:dd:d9:dd:c25:c25:94de:23ed
2392c19:dd:d9:dd:c25:c25:94de:23ee/1282c19:dd:d9:dd:c25:c25:94de:23ee
2402c19:dd:d9:dd:c25:c25:94de:23ef/1282c19:dd:d9:dd:c25:c25:94de:23ef
2412c19:dd:d9:dd:c25:c25:94de:23f0/1282c19:dd:d9:dd:c25:c25:94de:23f0
2422c19:dd:d9:dd:c25:c25:94de:23f1/1282c19:dd:d9:dd:c25:c25:94de:23f1
2432c19:dd:d9:dd:c25:c25:94de:23f2/1282c19:dd:d9:dd:c25:c25:94de:23f2
2442c19:dd:d9:dd:c25:c25:94de:23f3/1282c19:dd:d9:dd:c25:c25:94de:23f3
2452c19:dd:d9:dd:c25:c25:94de:23f4/1282c19:dd:d9:dd:c25:c25:94de:23f4
2462c19:dd:d9:dd:c25:c25:94de:23f5/1282c19:dd:d9:dd:c25:c25:94de:23f5
2472c19:dd:d9:dd:c25:c25:94de:23f6/1282c19:dd:d9:dd:c25:c25:94de:23f6
2482c19:dd:d9:dd:c25:c25:94de:23f7/1282c19:dd:d9:dd:c25:c25:94de:23f7
2492c19:dd:d9:dd:c25:c25:94de:23f8/1282c19:dd:d9:dd:c25:c25:94de:23f8
2502c19:dd:d9:dd:c25:c25:94de:23f9/1282c19:dd:d9:dd:c25:c25:94de:23f9
2512c19:dd:d9:dd:c25:c25:94de:23fa/1282c19:dd:d9:dd:c25:c25:94de:23fa
2522c19:dd:d9:dd:c25:c25:94de:23fb/1282c19:dd:d9:dd:c25:c25:94de:23fb
2532c19:dd:d9:dd:c25:c25:94de:23fc/1282c19:dd:d9:dd:c25:c25:94de:23fc
2542c19:dd:d9:dd:c25:c25:94de:23fd/1282c19:dd:d9:dd:c25:c25:94de:23fd
2552c19:dd:d9:dd:c25:c25:94de:23fe/1282c19:dd:d9:dd:c25:c25:94de:23fe
2562c19:dd:d9:dd:c25:c25:94de:23ff/1282c19:dd:d9:dd:c25:c25:94de:23ff

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.