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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:c25:c25:dd:dd:dd:3200/120
First address
2c19:dd:c25:c25:dd:dd:dd:3200
Last address
2c19:dd:c25:c25:dd:dd:dd:32ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:0c25:00dd:00dd:00dd:3200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.3.d.d.0.0.d.d.0.0.d.d.0.0.5.2.c.0.5.2.c.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:c25:c25:dd:dd:dd:3200/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:c25:c25:dd:dd:dd:3200/1282c19:dd:c25:c25:dd:dd:dd:3200
22c19:dd:c25:c25:dd:dd:dd:3201/1282c19:dd:c25:c25:dd:dd:dd:3201
32c19:dd:c25:c25:dd:dd:dd:3202/1282c19:dd:c25:c25:dd:dd:dd:3202
42c19:dd:c25:c25:dd:dd:dd:3203/1282c19:dd:c25:c25:dd:dd:dd:3203
52c19:dd:c25:c25:dd:dd:dd:3204/1282c19:dd:c25:c25:dd:dd:dd:3204
62c19:dd:c25:c25:dd:dd:dd:3205/1282c19:dd:c25:c25:dd:dd:dd:3205
72c19:dd:c25:c25:dd:dd:dd:3206/1282c19:dd:c25:c25:dd:dd:dd:3206
82c19:dd:c25:c25:dd:dd:dd:3207/1282c19:dd:c25:c25:dd:dd:dd:3207
92c19:dd:c25:c25:dd:dd:dd:3208/1282c19:dd:c25:c25:dd:dd:dd:3208
102c19:dd:c25:c25:dd:dd:dd:3209/1282c19:dd:c25:c25:dd:dd:dd:3209
112c19:dd:c25:c25:dd:dd:dd:320a/1282c19:dd:c25:c25:dd:dd:dd:320a
122c19:dd:c25:c25:dd:dd:dd:320b/1282c19:dd:c25:c25:dd:dd:dd:320b
132c19:dd:c25:c25:dd:dd:dd:320c/1282c19:dd:c25:c25:dd:dd:dd:320c
142c19:dd:c25:c25:dd:dd:dd:320d/1282c19:dd:c25:c25:dd:dd:dd:320d
152c19:dd:c25:c25:dd:dd:dd:320e/1282c19:dd:c25:c25:dd:dd:dd:320e
162c19:dd:c25:c25:dd:dd:dd:320f/1282c19:dd:c25:c25:dd:dd:dd:320f
172c19:dd:c25:c25:dd:dd:dd:3210/1282c19:dd:c25:c25:dd:dd:dd:3210
182c19:dd:c25:c25:dd:dd:dd:3211/1282c19:dd:c25:c25:dd:dd:dd:3211
192c19:dd:c25:c25:dd:dd:dd:3212/1282c19:dd:c25:c25:dd:dd:dd:3212
202c19:dd:c25:c25:dd:dd:dd:3213/1282c19:dd:c25:c25:dd:dd:dd:3213
212c19:dd:c25:c25:dd:dd:dd:3214/1282c19:dd:c25:c25:dd:dd:dd:3214
222c19:dd:c25:c25:dd:dd:dd:3215/1282c19:dd:c25:c25:dd:dd:dd:3215
232c19:dd:c25:c25:dd:dd:dd:3216/1282c19:dd:c25:c25:dd:dd:dd:3216
242c19:dd:c25:c25:dd:dd:dd:3217/1282c19:dd:c25:c25:dd:dd:dd:3217
252c19:dd:c25:c25:dd:dd:dd:3218/1282c19:dd:c25:c25:dd:dd:dd:3218
262c19:dd:c25:c25:dd:dd:dd:3219/1282c19:dd:c25:c25:dd:dd:dd:3219
272c19:dd:c25:c25:dd:dd:dd:321a/1282c19:dd:c25:c25:dd:dd:dd:321a
282c19:dd:c25:c25:dd:dd:dd:321b/1282c19:dd:c25:c25:dd:dd:dd:321b
292c19:dd:c25:c25:dd:dd:dd:321c/1282c19:dd:c25:c25:dd:dd:dd:321c
302c19:dd:c25:c25:dd:dd:dd:321d/1282c19:dd:c25:c25:dd:dd:dd:321d
312c19:dd:c25:c25:dd:dd:dd:321e/1282c19:dd:c25:c25:dd:dd:dd:321e
322c19:dd:c25:c25:dd:dd:dd:321f/1282c19:dd:c25:c25:dd:dd:dd:321f
332c19:dd:c25:c25:dd:dd:dd:3220/1282c19:dd:c25:c25:dd:dd:dd:3220
342c19:dd:c25:c25:dd:dd:dd:3221/1282c19:dd:c25:c25:dd:dd:dd:3221
352c19:dd:c25:c25:dd:dd:dd:3222/1282c19:dd:c25:c25:dd:dd:dd:3222
362c19:dd:c25:c25:dd:dd:dd:3223/1282c19:dd:c25:c25:dd:dd:dd:3223
372c19:dd:c25:c25:dd:dd:dd:3224/1282c19:dd:c25:c25:dd:dd:dd:3224
382c19:dd:c25:c25:dd:dd:dd:3225/1282c19:dd:c25:c25:dd:dd:dd:3225
392c19:dd:c25:c25:dd:dd:dd:3226/1282c19:dd:c25:c25:dd:dd:dd:3226
402c19:dd:c25:c25:dd:dd:dd:3227/1282c19:dd:c25:c25:dd:dd:dd:3227
412c19:dd:c25:c25:dd:dd:dd:3228/1282c19:dd:c25:c25:dd:dd:dd:3228
422c19:dd:c25:c25:dd:dd:dd:3229/1282c19:dd:c25:c25:dd:dd:dd:3229
432c19:dd:c25:c25:dd:dd:dd:322a/1282c19:dd:c25:c25:dd:dd:dd:322a
442c19:dd:c25:c25:dd:dd:dd:322b/1282c19:dd:c25:c25:dd:dd:dd:322b
452c19:dd:c25:c25:dd:dd:dd:322c/1282c19:dd:c25:c25:dd:dd:dd:322c
462c19:dd:c25:c25:dd:dd:dd:322d/1282c19:dd:c25:c25:dd:dd:dd:322d
472c19:dd:c25:c25:dd:dd:dd:322e/1282c19:dd:c25:c25:dd:dd:dd:322e
482c19:dd:c25:c25:dd:dd:dd:322f/1282c19:dd:c25:c25:dd:dd:dd:322f
492c19:dd:c25:c25:dd:dd:dd:3230/1282c19:dd:c25:c25:dd:dd:dd:3230
502c19:dd:c25:c25:dd:dd:dd:3231/1282c19:dd:c25:c25:dd:dd:dd:3231
512c19:dd:c25:c25:dd:dd:dd:3232/1282c19:dd:c25:c25:dd:dd:dd:3232
522c19:dd:c25:c25:dd:dd:dd:3233/1282c19:dd:c25:c25:dd:dd:dd:3233
532c19:dd:c25:c25:dd:dd:dd:3234/1282c19:dd:c25:c25:dd:dd:dd:3234
542c19:dd:c25:c25:dd:dd:dd:3235/1282c19:dd:c25:c25:dd:dd:dd:3235
552c19:dd:c25:c25:dd:dd:dd:3236/1282c19:dd:c25:c25:dd:dd:dd:3236
562c19:dd:c25:c25:dd:dd:dd:3237/1282c19:dd:c25:c25:dd:dd:dd:3237
572c19:dd:c25:c25:dd:dd:dd:3238/1282c19:dd:c25:c25:dd:dd:dd:3238
582c19:dd:c25:c25:dd:dd:dd:3239/1282c19:dd:c25:c25:dd:dd:dd:3239
592c19:dd:c25:c25:dd:dd:dd:323a/1282c19:dd:c25:c25:dd:dd:dd:323a
602c19:dd:c25:c25:dd:dd:dd:323b/1282c19:dd:c25:c25:dd:dd:dd:323b
612c19:dd:c25:c25:dd:dd:dd:323c/1282c19:dd:c25:c25:dd:dd:dd:323c
622c19:dd:c25:c25:dd:dd:dd:323d/1282c19:dd:c25:c25:dd:dd:dd:323d
632c19:dd:c25:c25:dd:dd:dd:323e/1282c19:dd:c25:c25:dd:dd:dd:323e
642c19:dd:c25:c25:dd:dd:dd:323f/1282c19:dd:c25:c25:dd:dd:dd:323f
652c19:dd:c25:c25:dd:dd:dd:3240/1282c19:dd:c25:c25:dd:dd:dd:3240
662c19:dd:c25:c25:dd:dd:dd:3241/1282c19:dd:c25:c25:dd:dd:dd:3241
672c19:dd:c25:c25:dd:dd:dd:3242/1282c19:dd:c25:c25:dd:dd:dd:3242
682c19:dd:c25:c25:dd:dd:dd:3243/1282c19:dd:c25:c25:dd:dd:dd:3243
692c19:dd:c25:c25:dd:dd:dd:3244/1282c19:dd:c25:c25:dd:dd:dd:3244
702c19:dd:c25:c25:dd:dd:dd:3245/1282c19:dd:c25:c25:dd:dd:dd:3245
712c19:dd:c25:c25:dd:dd:dd:3246/1282c19:dd:c25:c25:dd:dd:dd:3246
722c19:dd:c25:c25:dd:dd:dd:3247/1282c19:dd:c25:c25:dd:dd:dd:3247
732c19:dd:c25:c25:dd:dd:dd:3248/1282c19:dd:c25:c25:dd:dd:dd:3248
742c19:dd:c25:c25:dd:dd:dd:3249/1282c19:dd:c25:c25:dd:dd:dd:3249
752c19:dd:c25:c25:dd:dd:dd:324a/1282c19:dd:c25:c25:dd:dd:dd:324a
762c19:dd:c25:c25:dd:dd:dd:324b/1282c19:dd:c25:c25:dd:dd:dd:324b
772c19:dd:c25:c25:dd:dd:dd:324c/1282c19:dd:c25:c25:dd:dd:dd:324c
782c19:dd:c25:c25:dd:dd:dd:324d/1282c19:dd:c25:c25:dd:dd:dd:324d
792c19:dd:c25:c25:dd:dd:dd:324e/1282c19:dd:c25:c25:dd:dd:dd:324e
802c19:dd:c25:c25:dd:dd:dd:324f/1282c19:dd:c25:c25:dd:dd:dd:324f
812c19:dd:c25:c25:dd:dd:dd:3250/1282c19:dd:c25:c25:dd:dd:dd:3250
822c19:dd:c25:c25:dd:dd:dd:3251/1282c19:dd:c25:c25:dd:dd:dd:3251
832c19:dd:c25:c25:dd:dd:dd:3252/1282c19:dd:c25:c25:dd:dd:dd:3252
842c19:dd:c25:c25:dd:dd:dd:3253/1282c19:dd:c25:c25:dd:dd:dd:3253
852c19:dd:c25:c25:dd:dd:dd:3254/1282c19:dd:c25:c25:dd:dd:dd:3254
862c19:dd:c25:c25:dd:dd:dd:3255/1282c19:dd:c25:c25:dd:dd:dd:3255
872c19:dd:c25:c25:dd:dd:dd:3256/1282c19:dd:c25:c25:dd:dd:dd:3256
882c19:dd:c25:c25:dd:dd:dd:3257/1282c19:dd:c25:c25:dd:dd:dd:3257
892c19:dd:c25:c25:dd:dd:dd:3258/1282c19:dd:c25:c25:dd:dd:dd:3258
902c19:dd:c25:c25:dd:dd:dd:3259/1282c19:dd:c25:c25:dd:dd:dd:3259
912c19:dd:c25:c25:dd:dd:dd:325a/1282c19:dd:c25:c25:dd:dd:dd:325a
922c19:dd:c25:c25:dd:dd:dd:325b/1282c19:dd:c25:c25:dd:dd:dd:325b
932c19:dd:c25:c25:dd:dd:dd:325c/1282c19:dd:c25:c25:dd:dd:dd:325c
942c19:dd:c25:c25:dd:dd:dd:325d/1282c19:dd:c25:c25:dd:dd:dd:325d
952c19:dd:c25:c25:dd:dd:dd:325e/1282c19:dd:c25:c25:dd:dd:dd:325e
962c19:dd:c25:c25:dd:dd:dd:325f/1282c19:dd:c25:c25:dd:dd:dd:325f
972c19:dd:c25:c25:dd:dd:dd:3260/1282c19:dd:c25:c25:dd:dd:dd:3260
982c19:dd:c25:c25:dd:dd:dd:3261/1282c19:dd:c25:c25:dd:dd:dd:3261
992c19:dd:c25:c25:dd:dd:dd:3262/1282c19:dd:c25:c25:dd:dd:dd:3262
1002c19:dd:c25:c25:dd:dd:dd:3263/1282c19:dd:c25:c25:dd:dd:dd:3263
1012c19:dd:c25:c25:dd:dd:dd:3264/1282c19:dd:c25:c25:dd:dd:dd:3264
1022c19:dd:c25:c25:dd:dd:dd:3265/1282c19:dd:c25:c25:dd:dd:dd:3265
1032c19:dd:c25:c25:dd:dd:dd:3266/1282c19:dd:c25:c25:dd:dd:dd:3266
1042c19:dd:c25:c25:dd:dd:dd:3267/1282c19:dd:c25:c25:dd:dd:dd:3267
1052c19:dd:c25:c25:dd:dd:dd:3268/1282c19:dd:c25:c25:dd:dd:dd:3268
1062c19:dd:c25:c25:dd:dd:dd:3269/1282c19:dd:c25:c25:dd:dd:dd:3269
1072c19:dd:c25:c25:dd:dd:dd:326a/1282c19:dd:c25:c25:dd:dd:dd:326a
1082c19:dd:c25:c25:dd:dd:dd:326b/1282c19:dd:c25:c25:dd:dd:dd:326b
1092c19:dd:c25:c25:dd:dd:dd:326c/1282c19:dd:c25:c25:dd:dd:dd:326c
1102c19:dd:c25:c25:dd:dd:dd:326d/1282c19:dd:c25:c25:dd:dd:dd:326d
1112c19:dd:c25:c25:dd:dd:dd:326e/1282c19:dd:c25:c25:dd:dd:dd:326e
1122c19:dd:c25:c25:dd:dd:dd:326f/1282c19:dd:c25:c25:dd:dd:dd:326f
1132c19:dd:c25:c25:dd:dd:dd:3270/1282c19:dd:c25:c25:dd:dd:dd:3270
1142c19:dd:c25:c25:dd:dd:dd:3271/1282c19:dd:c25:c25:dd:dd:dd:3271
1152c19:dd:c25:c25:dd:dd:dd:3272/1282c19:dd:c25:c25:dd:dd:dd:3272
1162c19:dd:c25:c25:dd:dd:dd:3273/1282c19:dd:c25:c25:dd:dd:dd:3273
1172c19:dd:c25:c25:dd:dd:dd:3274/1282c19:dd:c25:c25:dd:dd:dd:3274
1182c19:dd:c25:c25:dd:dd:dd:3275/1282c19:dd:c25:c25:dd:dd:dd:3275
1192c19:dd:c25:c25:dd:dd:dd:3276/1282c19:dd:c25:c25:dd:dd:dd:3276
1202c19:dd:c25:c25:dd:dd:dd:3277/1282c19:dd:c25:c25:dd:dd:dd:3277
1212c19:dd:c25:c25:dd:dd:dd:3278/1282c19:dd:c25:c25:dd:dd:dd:3278
1222c19:dd:c25:c25:dd:dd:dd:3279/1282c19:dd:c25:c25:dd:dd:dd:3279
1232c19:dd:c25:c25:dd:dd:dd:327a/1282c19:dd:c25:c25:dd:dd:dd:327a
1242c19:dd:c25:c25:dd:dd:dd:327b/1282c19:dd:c25:c25:dd:dd:dd:327b
1252c19:dd:c25:c25:dd:dd:dd:327c/1282c19:dd:c25:c25:dd:dd:dd:327c
1262c19:dd:c25:c25:dd:dd:dd:327d/1282c19:dd:c25:c25:dd:dd:dd:327d
1272c19:dd:c25:c25:dd:dd:dd:327e/1282c19:dd:c25:c25:dd:dd:dd:327e
1282c19:dd:c25:c25:dd:dd:dd:327f/1282c19:dd:c25:c25:dd:dd:dd:327f
1292c19:dd:c25:c25:dd:dd:dd:3280/1282c19:dd:c25:c25:dd:dd:dd:3280
1302c19:dd:c25:c25:dd:dd:dd:3281/1282c19:dd:c25:c25:dd:dd:dd:3281
1312c19:dd:c25:c25:dd:dd:dd:3282/1282c19:dd:c25:c25:dd:dd:dd:3282
1322c19:dd:c25:c25:dd:dd:dd:3283/1282c19:dd:c25:c25:dd:dd:dd:3283
1332c19:dd:c25:c25:dd:dd:dd:3284/1282c19:dd:c25:c25:dd:dd:dd:3284
1342c19:dd:c25:c25:dd:dd:dd:3285/1282c19:dd:c25:c25:dd:dd:dd:3285
1352c19:dd:c25:c25:dd:dd:dd:3286/1282c19:dd:c25:c25:dd:dd:dd:3286
1362c19:dd:c25:c25:dd:dd:dd:3287/1282c19:dd:c25:c25:dd:dd:dd:3287
1372c19:dd:c25:c25:dd:dd:dd:3288/1282c19:dd:c25:c25:dd:dd:dd:3288
1382c19:dd:c25:c25:dd:dd:dd:3289/1282c19:dd:c25:c25:dd:dd:dd:3289
1392c19:dd:c25:c25:dd:dd:dd:328a/1282c19:dd:c25:c25:dd:dd:dd:328a
1402c19:dd:c25:c25:dd:dd:dd:328b/1282c19:dd:c25:c25:dd:dd:dd:328b
1412c19:dd:c25:c25:dd:dd:dd:328c/1282c19:dd:c25:c25:dd:dd:dd:328c
1422c19:dd:c25:c25:dd:dd:dd:328d/1282c19:dd:c25:c25:dd:dd:dd:328d
1432c19:dd:c25:c25:dd:dd:dd:328e/1282c19:dd:c25:c25:dd:dd:dd:328e
1442c19:dd:c25:c25:dd:dd:dd:328f/1282c19:dd:c25:c25:dd:dd:dd:328f
1452c19:dd:c25:c25:dd:dd:dd:3290/1282c19:dd:c25:c25:dd:dd:dd:3290
1462c19:dd:c25:c25:dd:dd:dd:3291/1282c19:dd:c25:c25:dd:dd:dd:3291
1472c19:dd:c25:c25:dd:dd:dd:3292/1282c19:dd:c25:c25:dd:dd:dd:3292
1482c19:dd:c25:c25:dd:dd:dd:3293/1282c19:dd:c25:c25:dd:dd:dd:3293
1492c19:dd:c25:c25:dd:dd:dd:3294/1282c19:dd:c25:c25:dd:dd:dd:3294
1502c19:dd:c25:c25:dd:dd:dd:3295/1282c19:dd:c25:c25:dd:dd:dd:3295
1512c19:dd:c25:c25:dd:dd:dd:3296/1282c19:dd:c25:c25:dd:dd:dd:3296
1522c19:dd:c25:c25:dd:dd:dd:3297/1282c19:dd:c25:c25:dd:dd:dd:3297
1532c19:dd:c25:c25:dd:dd:dd:3298/1282c19:dd:c25:c25:dd:dd:dd:3298
1542c19:dd:c25:c25:dd:dd:dd:3299/1282c19:dd:c25:c25:dd:dd:dd:3299
1552c19:dd:c25:c25:dd:dd:dd:329a/1282c19:dd:c25:c25:dd:dd:dd:329a
1562c19:dd:c25:c25:dd:dd:dd:329b/1282c19:dd:c25:c25:dd:dd:dd:329b
1572c19:dd:c25:c25:dd:dd:dd:329c/1282c19:dd:c25:c25:dd:dd:dd:329c
1582c19:dd:c25:c25:dd:dd:dd:329d/1282c19:dd:c25:c25:dd:dd:dd:329d
1592c19:dd:c25:c25:dd:dd:dd:329e/1282c19:dd:c25:c25:dd:dd:dd:329e
1602c19:dd:c25:c25:dd:dd:dd:329f/1282c19:dd:c25:c25:dd:dd:dd:329f
1612c19:dd:c25:c25:dd:dd:dd:32a0/1282c19:dd:c25:c25:dd:dd:dd:32a0
1622c19:dd:c25:c25:dd:dd:dd:32a1/1282c19:dd:c25:c25:dd:dd:dd:32a1
1632c19:dd:c25:c25:dd:dd:dd:32a2/1282c19:dd:c25:c25:dd:dd:dd:32a2
1642c19:dd:c25:c25:dd:dd:dd:32a3/1282c19:dd:c25:c25:dd:dd:dd:32a3
1652c19:dd:c25:c25:dd:dd:dd:32a4/1282c19:dd:c25:c25:dd:dd:dd:32a4
1662c19:dd:c25:c25:dd:dd:dd:32a5/1282c19:dd:c25:c25:dd:dd:dd:32a5
1672c19:dd:c25:c25:dd:dd:dd:32a6/1282c19:dd:c25:c25:dd:dd:dd:32a6
1682c19:dd:c25:c25:dd:dd:dd:32a7/1282c19:dd:c25:c25:dd:dd:dd:32a7
1692c19:dd:c25:c25:dd:dd:dd:32a8/1282c19:dd:c25:c25:dd:dd:dd:32a8
1702c19:dd:c25:c25:dd:dd:dd:32a9/1282c19:dd:c25:c25:dd:dd:dd:32a9
1712c19:dd:c25:c25:dd:dd:dd:32aa/1282c19:dd:c25:c25:dd:dd:dd:32aa
1722c19:dd:c25:c25:dd:dd:dd:32ab/1282c19:dd:c25:c25:dd:dd:dd:32ab
1732c19:dd:c25:c25:dd:dd:dd:32ac/1282c19:dd:c25:c25:dd:dd:dd:32ac
1742c19:dd:c25:c25:dd:dd:dd:32ad/1282c19:dd:c25:c25:dd:dd:dd:32ad
1752c19:dd:c25:c25:dd:dd:dd:32ae/1282c19:dd:c25:c25:dd:dd:dd:32ae
1762c19:dd:c25:c25:dd:dd:dd:32af/1282c19:dd:c25:c25:dd:dd:dd:32af
1772c19:dd:c25:c25:dd:dd:dd:32b0/1282c19:dd:c25:c25:dd:dd:dd:32b0
1782c19:dd:c25:c25:dd:dd:dd:32b1/1282c19:dd:c25:c25:dd:dd:dd:32b1
1792c19:dd:c25:c25:dd:dd:dd:32b2/1282c19:dd:c25:c25:dd:dd:dd:32b2
1802c19:dd:c25:c25:dd:dd:dd:32b3/1282c19:dd:c25:c25:dd:dd:dd:32b3
1812c19:dd:c25:c25:dd:dd:dd:32b4/1282c19:dd:c25:c25:dd:dd:dd:32b4
1822c19:dd:c25:c25:dd:dd:dd:32b5/1282c19:dd:c25:c25:dd:dd:dd:32b5
1832c19:dd:c25:c25:dd:dd:dd:32b6/1282c19:dd:c25:c25:dd:dd:dd:32b6
1842c19:dd:c25:c25:dd:dd:dd:32b7/1282c19:dd:c25:c25:dd:dd:dd:32b7
1852c19:dd:c25:c25:dd:dd:dd:32b8/1282c19:dd:c25:c25:dd:dd:dd:32b8
1862c19:dd:c25:c25:dd:dd:dd:32b9/1282c19:dd:c25:c25:dd:dd:dd:32b9
1872c19:dd:c25:c25:dd:dd:dd:32ba/1282c19:dd:c25:c25:dd:dd:dd:32ba
1882c19:dd:c25:c25:dd:dd:dd:32bb/1282c19:dd:c25:c25:dd:dd:dd:32bb
1892c19:dd:c25:c25:dd:dd:dd:32bc/1282c19:dd:c25:c25:dd:dd:dd:32bc
1902c19:dd:c25:c25:dd:dd:dd:32bd/1282c19:dd:c25:c25:dd:dd:dd:32bd
1912c19:dd:c25:c25:dd:dd:dd:32be/1282c19:dd:c25:c25:dd:dd:dd:32be
1922c19:dd:c25:c25:dd:dd:dd:32bf/1282c19:dd:c25:c25:dd:dd:dd:32bf
1932c19:dd:c25:c25:dd:dd:dd:32c0/1282c19:dd:c25:c25:dd:dd:dd:32c0
1942c19:dd:c25:c25:dd:dd:dd:32c1/1282c19:dd:c25:c25:dd:dd:dd:32c1
1952c19:dd:c25:c25:dd:dd:dd:32c2/1282c19:dd:c25:c25:dd:dd:dd:32c2
1962c19:dd:c25:c25:dd:dd:dd:32c3/1282c19:dd:c25:c25:dd:dd:dd:32c3
1972c19:dd:c25:c25:dd:dd:dd:32c4/1282c19:dd:c25:c25:dd:dd:dd:32c4
1982c19:dd:c25:c25:dd:dd:dd:32c5/1282c19:dd:c25:c25:dd:dd:dd:32c5
1992c19:dd:c25:c25:dd:dd:dd:32c6/1282c19:dd:c25:c25:dd:dd:dd:32c6
2002c19:dd:c25:c25:dd:dd:dd:32c7/1282c19:dd:c25:c25:dd:dd:dd:32c7
2012c19:dd:c25:c25:dd:dd:dd:32c8/1282c19:dd:c25:c25:dd:dd:dd:32c8
2022c19:dd:c25:c25:dd:dd:dd:32c9/1282c19:dd:c25:c25:dd:dd:dd:32c9
2032c19:dd:c25:c25:dd:dd:dd:32ca/1282c19:dd:c25:c25:dd:dd:dd:32ca
2042c19:dd:c25:c25:dd:dd:dd:32cb/1282c19:dd:c25:c25:dd:dd:dd:32cb
2052c19:dd:c25:c25:dd:dd:dd:32cc/1282c19:dd:c25:c25:dd:dd:dd:32cc
2062c19:dd:c25:c25:dd:dd:dd:32cd/1282c19:dd:c25:c25:dd:dd:dd:32cd
2072c19:dd:c25:c25:dd:dd:dd:32ce/1282c19:dd:c25:c25:dd:dd:dd:32ce
2082c19:dd:c25:c25:dd:dd:dd:32cf/1282c19:dd:c25:c25:dd:dd:dd:32cf
2092c19:dd:c25:c25:dd:dd:dd:32d0/1282c19:dd:c25:c25:dd:dd:dd:32d0
2102c19:dd:c25:c25:dd:dd:dd:32d1/1282c19:dd:c25:c25:dd:dd:dd:32d1
2112c19:dd:c25:c25:dd:dd:dd:32d2/1282c19:dd:c25:c25:dd:dd:dd:32d2
2122c19:dd:c25:c25:dd:dd:dd:32d3/1282c19:dd:c25:c25:dd:dd:dd:32d3
2132c19:dd:c25:c25:dd:dd:dd:32d4/1282c19:dd:c25:c25:dd:dd:dd:32d4
2142c19:dd:c25:c25:dd:dd:dd:32d5/1282c19:dd:c25:c25:dd:dd:dd:32d5
2152c19:dd:c25:c25:dd:dd:dd:32d6/1282c19:dd:c25:c25:dd:dd:dd:32d6
2162c19:dd:c25:c25:dd:dd:dd:32d7/1282c19:dd:c25:c25:dd:dd:dd:32d7
2172c19:dd:c25:c25:dd:dd:dd:32d8/1282c19:dd:c25:c25:dd:dd:dd:32d8
2182c19:dd:c25:c25:dd:dd:dd:32d9/1282c19:dd:c25:c25:dd:dd:dd:32d9
2192c19:dd:c25:c25:dd:dd:dd:32da/1282c19:dd:c25:c25:dd:dd:dd:32da
2202c19:dd:c25:c25:dd:dd:dd:32db/1282c19:dd:c25:c25:dd:dd:dd:32db
2212c19:dd:c25:c25:dd:dd:dd:32dc/1282c19:dd:c25:c25:dd:dd:dd:32dc
2222c19:dd:c25:c25:dd:dd:dd:32dd/1282c19:dd:c25:c25:dd:dd:dd:32dd
2232c19:dd:c25:c25:dd:dd:dd:32de/1282c19:dd:c25:c25:dd:dd:dd:32de
2242c19:dd:c25:c25:dd:dd:dd:32df/1282c19:dd:c25:c25:dd:dd:dd:32df
2252c19:dd:c25:c25:dd:dd:dd:32e0/1282c19:dd:c25:c25:dd:dd:dd:32e0
2262c19:dd:c25:c25:dd:dd:dd:32e1/1282c19:dd:c25:c25:dd:dd:dd:32e1
2272c19:dd:c25:c25:dd:dd:dd:32e2/1282c19:dd:c25:c25:dd:dd:dd:32e2
2282c19:dd:c25:c25:dd:dd:dd:32e3/1282c19:dd:c25:c25:dd:dd:dd:32e3
2292c19:dd:c25:c25:dd:dd:dd:32e4/1282c19:dd:c25:c25:dd:dd:dd:32e4
2302c19:dd:c25:c25:dd:dd:dd:32e5/1282c19:dd:c25:c25:dd:dd:dd:32e5
2312c19:dd:c25:c25:dd:dd:dd:32e6/1282c19:dd:c25:c25:dd:dd:dd:32e6
2322c19:dd:c25:c25:dd:dd:dd:32e7/1282c19:dd:c25:c25:dd:dd:dd:32e7
2332c19:dd:c25:c25:dd:dd:dd:32e8/1282c19:dd:c25:c25:dd:dd:dd:32e8
2342c19:dd:c25:c25:dd:dd:dd:32e9/1282c19:dd:c25:c25:dd:dd:dd:32e9
2352c19:dd:c25:c25:dd:dd:dd:32ea/1282c19:dd:c25:c25:dd:dd:dd:32ea
2362c19:dd:c25:c25:dd:dd:dd:32eb/1282c19:dd:c25:c25:dd:dd:dd:32eb
2372c19:dd:c25:c25:dd:dd:dd:32ec/1282c19:dd:c25:c25:dd:dd:dd:32ec
2382c19:dd:c25:c25:dd:dd:dd:32ed/1282c19:dd:c25:c25:dd:dd:dd:32ed
2392c19:dd:c25:c25:dd:dd:dd:32ee/1282c19:dd:c25:c25:dd:dd:dd:32ee
2402c19:dd:c25:c25:dd:dd:dd:32ef/1282c19:dd:c25:c25:dd:dd:dd:32ef
2412c19:dd:c25:c25:dd:dd:dd:32f0/1282c19:dd:c25:c25:dd:dd:dd:32f0
2422c19:dd:c25:c25:dd:dd:dd:32f1/1282c19:dd:c25:c25:dd:dd:dd:32f1
2432c19:dd:c25:c25:dd:dd:dd:32f2/1282c19:dd:c25:c25:dd:dd:dd:32f2
2442c19:dd:c25:c25:dd:dd:dd:32f3/1282c19:dd:c25:c25:dd:dd:dd:32f3
2452c19:dd:c25:c25:dd:dd:dd:32f4/1282c19:dd:c25:c25:dd:dd:dd:32f4
2462c19:dd:c25:c25:dd:dd:dd:32f5/1282c19:dd:c25:c25:dd:dd:dd:32f5
2472c19:dd:c25:c25:dd:dd:dd:32f6/1282c19:dd:c25:c25:dd:dd:dd:32f6
2482c19:dd:c25:c25:dd:dd:dd:32f7/1282c19:dd:c25:c25:dd:dd:dd:32f7
2492c19:dd:c25:c25:dd:dd:dd:32f8/1282c19:dd:c25:c25:dd:dd:dd:32f8
2502c19:dd:c25:c25:dd:dd:dd:32f9/1282c19:dd:c25:c25:dd:dd:dd:32f9
2512c19:dd:c25:c25:dd:dd:dd:32fa/1282c19:dd:c25:c25:dd:dd:dd:32fa
2522c19:dd:c25:c25:dd:dd:dd:32fb/1282c19:dd:c25:c25:dd:dd:dd:32fb
2532c19:dd:c25:c25:dd:dd:dd:32fc/1282c19:dd:c25:c25:dd:dd:dd:32fc
2542c19:dd:c25:c25:dd:dd:dd:32fd/1282c19:dd:c25:c25:dd:dd:dd:32fd
2552c19:dd:c25:c25:dd:dd:dd:32fe/1282c19:dd:c25:c25:dd:dd:dd:32fe
2562c19:dd:c25:c25:dd:dd:dd:32ff/1282c19:dd:c25:c25:dd:dd:dd:32ff

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.