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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:c25d:dd:dd:dd:2200/120
First address
2c19:dd:c25:c25d:dd:dd:dd:2200
Last address
2c19:dd:c25:c25d:dd:dd:dd:22ff
Addresses
256
/64 networks (LANs)
None: smaller than one /64 LAN
Full form
2c19:00dd:0c25:c25d:00dd:00dd:00dd:2200
Type
Global unicast 2000::/3
Public internet addresses
Reverse DNS zone
2.2.d.d.0.0.d.d.0.0.d.d.0.0.d.5.2.c.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:c25d:dd:dd:dd:2200/120 makes 256 subnets of /128.

Subnets
#SubnetLast address
12c19:dd:c25:c25d:dd:dd:dd:2200/1282c19:dd:c25:c25d:dd:dd:dd:2200
22c19:dd:c25:c25d:dd:dd:dd:2201/1282c19:dd:c25:c25d:dd:dd:dd:2201
32c19:dd:c25:c25d:dd:dd:dd:2202/1282c19:dd:c25:c25d:dd:dd:dd:2202
42c19:dd:c25:c25d:dd:dd:dd:2203/1282c19:dd:c25:c25d:dd:dd:dd:2203
52c19:dd:c25:c25d:dd:dd:dd:2204/1282c19:dd:c25:c25d:dd:dd:dd:2204
62c19:dd:c25:c25d:dd:dd:dd:2205/1282c19:dd:c25:c25d:dd:dd:dd:2205
72c19:dd:c25:c25d:dd:dd:dd:2206/1282c19:dd:c25:c25d:dd:dd:dd:2206
82c19:dd:c25:c25d:dd:dd:dd:2207/1282c19:dd:c25:c25d:dd:dd:dd:2207
92c19:dd:c25:c25d:dd:dd:dd:2208/1282c19:dd:c25:c25d:dd:dd:dd:2208
102c19:dd:c25:c25d:dd:dd:dd:2209/1282c19:dd:c25:c25d:dd:dd:dd:2209
112c19:dd:c25:c25d:dd:dd:dd:220a/1282c19:dd:c25:c25d:dd:dd:dd:220a
122c19:dd:c25:c25d:dd:dd:dd:220b/1282c19:dd:c25:c25d:dd:dd:dd:220b
132c19:dd:c25:c25d:dd:dd:dd:220c/1282c19:dd:c25:c25d:dd:dd:dd:220c
142c19:dd:c25:c25d:dd:dd:dd:220d/1282c19:dd:c25:c25d:dd:dd:dd:220d
152c19:dd:c25:c25d:dd:dd:dd:220e/1282c19:dd:c25:c25d:dd:dd:dd:220e
162c19:dd:c25:c25d:dd:dd:dd:220f/1282c19:dd:c25:c25d:dd:dd:dd:220f
172c19:dd:c25:c25d:dd:dd:dd:2210/1282c19:dd:c25:c25d:dd:dd:dd:2210
182c19:dd:c25:c25d:dd:dd:dd:2211/1282c19:dd:c25:c25d:dd:dd:dd:2211
192c19:dd:c25:c25d:dd:dd:dd:2212/1282c19:dd:c25:c25d:dd:dd:dd:2212
202c19:dd:c25:c25d:dd:dd:dd:2213/1282c19:dd:c25:c25d:dd:dd:dd:2213
212c19:dd:c25:c25d:dd:dd:dd:2214/1282c19:dd:c25:c25d:dd:dd:dd:2214
222c19:dd:c25:c25d:dd:dd:dd:2215/1282c19:dd:c25:c25d:dd:dd:dd:2215
232c19:dd:c25:c25d:dd:dd:dd:2216/1282c19:dd:c25:c25d:dd:dd:dd:2216
242c19:dd:c25:c25d:dd:dd:dd:2217/1282c19:dd:c25:c25d:dd:dd:dd:2217
252c19:dd:c25:c25d:dd:dd:dd:2218/1282c19:dd:c25:c25d:dd:dd:dd:2218
262c19:dd:c25:c25d:dd:dd:dd:2219/1282c19:dd:c25:c25d:dd:dd:dd:2219
272c19:dd:c25:c25d:dd:dd:dd:221a/1282c19:dd:c25:c25d:dd:dd:dd:221a
282c19:dd:c25:c25d:dd:dd:dd:221b/1282c19:dd:c25:c25d:dd:dd:dd:221b
292c19:dd:c25:c25d:dd:dd:dd:221c/1282c19:dd:c25:c25d:dd:dd:dd:221c
302c19:dd:c25:c25d:dd:dd:dd:221d/1282c19:dd:c25:c25d:dd:dd:dd:221d
312c19:dd:c25:c25d:dd:dd:dd:221e/1282c19:dd:c25:c25d:dd:dd:dd:221e
322c19:dd:c25:c25d:dd:dd:dd:221f/1282c19:dd:c25:c25d:dd:dd:dd:221f
332c19:dd:c25:c25d:dd:dd:dd:2220/1282c19:dd:c25:c25d:dd:dd:dd:2220
342c19:dd:c25:c25d:dd:dd:dd:2221/1282c19:dd:c25:c25d:dd:dd:dd:2221
352c19:dd:c25:c25d:dd:dd:dd:2222/1282c19:dd:c25:c25d:dd:dd:dd:2222
362c19:dd:c25:c25d:dd:dd:dd:2223/1282c19:dd:c25:c25d:dd:dd:dd:2223
372c19:dd:c25:c25d:dd:dd:dd:2224/1282c19:dd:c25:c25d:dd:dd:dd:2224
382c19:dd:c25:c25d:dd:dd:dd:2225/1282c19:dd:c25:c25d:dd:dd:dd:2225
392c19:dd:c25:c25d:dd:dd:dd:2226/1282c19:dd:c25:c25d:dd:dd:dd:2226
402c19:dd:c25:c25d:dd:dd:dd:2227/1282c19:dd:c25:c25d:dd:dd:dd:2227
412c19:dd:c25:c25d:dd:dd:dd:2228/1282c19:dd:c25:c25d:dd:dd:dd:2228
422c19:dd:c25:c25d:dd:dd:dd:2229/1282c19:dd:c25:c25d:dd:dd:dd:2229
432c19:dd:c25:c25d:dd:dd:dd:222a/1282c19:dd:c25:c25d:dd:dd:dd:222a
442c19:dd:c25:c25d:dd:dd:dd:222b/1282c19:dd:c25:c25d:dd:dd:dd:222b
452c19:dd:c25:c25d:dd:dd:dd:222c/1282c19:dd:c25:c25d:dd:dd:dd:222c
462c19:dd:c25:c25d:dd:dd:dd:222d/1282c19:dd:c25:c25d:dd:dd:dd:222d
472c19:dd:c25:c25d:dd:dd:dd:222e/1282c19:dd:c25:c25d:dd:dd:dd:222e
482c19:dd:c25:c25d:dd:dd:dd:222f/1282c19:dd:c25:c25d:dd:dd:dd:222f
492c19:dd:c25:c25d:dd:dd:dd:2230/1282c19:dd:c25:c25d:dd:dd:dd:2230
502c19:dd:c25:c25d:dd:dd:dd:2231/1282c19:dd:c25:c25d:dd:dd:dd:2231
512c19:dd:c25:c25d:dd:dd:dd:2232/1282c19:dd:c25:c25d:dd:dd:dd:2232
522c19:dd:c25:c25d:dd:dd:dd:2233/1282c19:dd:c25:c25d:dd:dd:dd:2233
532c19:dd:c25:c25d:dd:dd:dd:2234/1282c19:dd:c25:c25d:dd:dd:dd:2234
542c19:dd:c25:c25d:dd:dd:dd:2235/1282c19:dd:c25:c25d:dd:dd:dd:2235
552c19:dd:c25:c25d:dd:dd:dd:2236/1282c19:dd:c25:c25d:dd:dd:dd:2236
562c19:dd:c25:c25d:dd:dd:dd:2237/1282c19:dd:c25:c25d:dd:dd:dd:2237
572c19:dd:c25:c25d:dd:dd:dd:2238/1282c19:dd:c25:c25d:dd:dd:dd:2238
582c19:dd:c25:c25d:dd:dd:dd:2239/1282c19:dd:c25:c25d:dd:dd:dd:2239
592c19:dd:c25:c25d:dd:dd:dd:223a/1282c19:dd:c25:c25d:dd:dd:dd:223a
602c19:dd:c25:c25d:dd:dd:dd:223b/1282c19:dd:c25:c25d:dd:dd:dd:223b
612c19:dd:c25:c25d:dd:dd:dd:223c/1282c19:dd:c25:c25d:dd:dd:dd:223c
622c19:dd:c25:c25d:dd:dd:dd:223d/1282c19:dd:c25:c25d:dd:dd:dd:223d
632c19:dd:c25:c25d:dd:dd:dd:223e/1282c19:dd:c25:c25d:dd:dd:dd:223e
642c19:dd:c25:c25d:dd:dd:dd:223f/1282c19:dd:c25:c25d:dd:dd:dd:223f
652c19:dd:c25:c25d:dd:dd:dd:2240/1282c19:dd:c25:c25d:dd:dd:dd:2240
662c19:dd:c25:c25d:dd:dd:dd:2241/1282c19:dd:c25:c25d:dd:dd:dd:2241
672c19:dd:c25:c25d:dd:dd:dd:2242/1282c19:dd:c25:c25d:dd:dd:dd:2242
682c19:dd:c25:c25d:dd:dd:dd:2243/1282c19:dd:c25:c25d:dd:dd:dd:2243
692c19:dd:c25:c25d:dd:dd:dd:2244/1282c19:dd:c25:c25d:dd:dd:dd:2244
702c19:dd:c25:c25d:dd:dd:dd:2245/1282c19:dd:c25:c25d:dd:dd:dd:2245
712c19:dd:c25:c25d:dd:dd:dd:2246/1282c19:dd:c25:c25d:dd:dd:dd:2246
722c19:dd:c25:c25d:dd:dd:dd:2247/1282c19:dd:c25:c25d:dd:dd:dd:2247
732c19:dd:c25:c25d:dd:dd:dd:2248/1282c19:dd:c25:c25d:dd:dd:dd:2248
742c19:dd:c25:c25d:dd:dd:dd:2249/1282c19:dd:c25:c25d:dd:dd:dd:2249
752c19:dd:c25:c25d:dd:dd:dd:224a/1282c19:dd:c25:c25d:dd:dd:dd:224a
762c19:dd:c25:c25d:dd:dd:dd:224b/1282c19:dd:c25:c25d:dd:dd:dd:224b
772c19:dd:c25:c25d:dd:dd:dd:224c/1282c19:dd:c25:c25d:dd:dd:dd:224c
782c19:dd:c25:c25d:dd:dd:dd:224d/1282c19:dd:c25:c25d:dd:dd:dd:224d
792c19:dd:c25:c25d:dd:dd:dd:224e/1282c19:dd:c25:c25d:dd:dd:dd:224e
802c19:dd:c25:c25d:dd:dd:dd:224f/1282c19:dd:c25:c25d:dd:dd:dd:224f
812c19:dd:c25:c25d:dd:dd:dd:2250/1282c19:dd:c25:c25d:dd:dd:dd:2250
822c19:dd:c25:c25d:dd:dd:dd:2251/1282c19:dd:c25:c25d:dd:dd:dd:2251
832c19:dd:c25:c25d:dd:dd:dd:2252/1282c19:dd:c25:c25d:dd:dd:dd:2252
842c19:dd:c25:c25d:dd:dd:dd:2253/1282c19:dd:c25:c25d:dd:dd:dd:2253
852c19:dd:c25:c25d:dd:dd:dd:2254/1282c19:dd:c25:c25d:dd:dd:dd:2254
862c19:dd:c25:c25d:dd:dd:dd:2255/1282c19:dd:c25:c25d:dd:dd:dd:2255
872c19:dd:c25:c25d:dd:dd:dd:2256/1282c19:dd:c25:c25d:dd:dd:dd:2256
882c19:dd:c25:c25d:dd:dd:dd:2257/1282c19:dd:c25:c25d:dd:dd:dd:2257
892c19:dd:c25:c25d:dd:dd:dd:2258/1282c19:dd:c25:c25d:dd:dd:dd:2258
902c19:dd:c25:c25d:dd:dd:dd:2259/1282c19:dd:c25:c25d:dd:dd:dd:2259
912c19:dd:c25:c25d:dd:dd:dd:225a/1282c19:dd:c25:c25d:dd:dd:dd:225a
922c19:dd:c25:c25d:dd:dd:dd:225b/1282c19:dd:c25:c25d:dd:dd:dd:225b
932c19:dd:c25:c25d:dd:dd:dd:225c/1282c19:dd:c25:c25d:dd:dd:dd:225c
942c19:dd:c25:c25d:dd:dd:dd:225d/1282c19:dd:c25:c25d:dd:dd:dd:225d
952c19:dd:c25:c25d:dd:dd:dd:225e/1282c19:dd:c25:c25d:dd:dd:dd:225e
962c19:dd:c25:c25d:dd:dd:dd:225f/1282c19:dd:c25:c25d:dd:dd:dd:225f
972c19:dd:c25:c25d:dd:dd:dd:2260/1282c19:dd:c25:c25d:dd:dd:dd:2260
982c19:dd:c25:c25d:dd:dd:dd:2261/1282c19:dd:c25:c25d:dd:dd:dd:2261
992c19:dd:c25:c25d:dd:dd:dd:2262/1282c19:dd:c25:c25d:dd:dd:dd:2262
1002c19:dd:c25:c25d:dd:dd:dd:2263/1282c19:dd:c25:c25d:dd:dd:dd:2263
1012c19:dd:c25:c25d:dd:dd:dd:2264/1282c19:dd:c25:c25d:dd:dd:dd:2264
1022c19:dd:c25:c25d:dd:dd:dd:2265/1282c19:dd:c25:c25d:dd:dd:dd:2265
1032c19:dd:c25:c25d:dd:dd:dd:2266/1282c19:dd:c25:c25d:dd:dd:dd:2266
1042c19:dd:c25:c25d:dd:dd:dd:2267/1282c19:dd:c25:c25d:dd:dd:dd:2267
1052c19:dd:c25:c25d:dd:dd:dd:2268/1282c19:dd:c25:c25d:dd:dd:dd:2268
1062c19:dd:c25:c25d:dd:dd:dd:2269/1282c19:dd:c25:c25d:dd:dd:dd:2269
1072c19:dd:c25:c25d:dd:dd:dd:226a/1282c19:dd:c25:c25d:dd:dd:dd:226a
1082c19:dd:c25:c25d:dd:dd:dd:226b/1282c19:dd:c25:c25d:dd:dd:dd:226b
1092c19:dd:c25:c25d:dd:dd:dd:226c/1282c19:dd:c25:c25d:dd:dd:dd:226c
1102c19:dd:c25:c25d:dd:dd:dd:226d/1282c19:dd:c25:c25d:dd:dd:dd:226d
1112c19:dd:c25:c25d:dd:dd:dd:226e/1282c19:dd:c25:c25d:dd:dd:dd:226e
1122c19:dd:c25:c25d:dd:dd:dd:226f/1282c19:dd:c25:c25d:dd:dd:dd:226f
1132c19:dd:c25:c25d:dd:dd:dd:2270/1282c19:dd:c25:c25d:dd:dd:dd:2270
1142c19:dd:c25:c25d:dd:dd:dd:2271/1282c19:dd:c25:c25d:dd:dd:dd:2271
1152c19:dd:c25:c25d:dd:dd:dd:2272/1282c19:dd:c25:c25d:dd:dd:dd:2272
1162c19:dd:c25:c25d:dd:dd:dd:2273/1282c19:dd:c25:c25d:dd:dd:dd:2273
1172c19:dd:c25:c25d:dd:dd:dd:2274/1282c19:dd:c25:c25d:dd:dd:dd:2274
1182c19:dd:c25:c25d:dd:dd:dd:2275/1282c19:dd:c25:c25d:dd:dd:dd:2275
1192c19:dd:c25:c25d:dd:dd:dd:2276/1282c19:dd:c25:c25d:dd:dd:dd:2276
1202c19:dd:c25:c25d:dd:dd:dd:2277/1282c19:dd:c25:c25d:dd:dd:dd:2277
1212c19:dd:c25:c25d:dd:dd:dd:2278/1282c19:dd:c25:c25d:dd:dd:dd:2278
1222c19:dd:c25:c25d:dd:dd:dd:2279/1282c19:dd:c25:c25d:dd:dd:dd:2279
1232c19:dd:c25:c25d:dd:dd:dd:227a/1282c19:dd:c25:c25d:dd:dd:dd:227a
1242c19:dd:c25:c25d:dd:dd:dd:227b/1282c19:dd:c25:c25d:dd:dd:dd:227b
1252c19:dd:c25:c25d:dd:dd:dd:227c/1282c19:dd:c25:c25d:dd:dd:dd:227c
1262c19:dd:c25:c25d:dd:dd:dd:227d/1282c19:dd:c25:c25d:dd:dd:dd:227d
1272c19:dd:c25:c25d:dd:dd:dd:227e/1282c19:dd:c25:c25d:dd:dd:dd:227e
1282c19:dd:c25:c25d:dd:dd:dd:227f/1282c19:dd:c25:c25d:dd:dd:dd:227f
1292c19:dd:c25:c25d:dd:dd:dd:2280/1282c19:dd:c25:c25d:dd:dd:dd:2280
1302c19:dd:c25:c25d:dd:dd:dd:2281/1282c19:dd:c25:c25d:dd:dd:dd:2281
1312c19:dd:c25:c25d:dd:dd:dd:2282/1282c19:dd:c25:c25d:dd:dd:dd:2282
1322c19:dd:c25:c25d:dd:dd:dd:2283/1282c19:dd:c25:c25d:dd:dd:dd:2283
1332c19:dd:c25:c25d:dd:dd:dd:2284/1282c19:dd:c25:c25d:dd:dd:dd:2284
1342c19:dd:c25:c25d:dd:dd:dd:2285/1282c19:dd:c25:c25d:dd:dd:dd:2285
1352c19:dd:c25:c25d:dd:dd:dd:2286/1282c19:dd:c25:c25d:dd:dd:dd:2286
1362c19:dd:c25:c25d:dd:dd:dd:2287/1282c19:dd:c25:c25d:dd:dd:dd:2287
1372c19:dd:c25:c25d:dd:dd:dd:2288/1282c19:dd:c25:c25d:dd:dd:dd:2288
1382c19:dd:c25:c25d:dd:dd:dd:2289/1282c19:dd:c25:c25d:dd:dd:dd:2289
1392c19:dd:c25:c25d:dd:dd:dd:228a/1282c19:dd:c25:c25d:dd:dd:dd:228a
1402c19:dd:c25:c25d:dd:dd:dd:228b/1282c19:dd:c25:c25d:dd:dd:dd:228b
1412c19:dd:c25:c25d:dd:dd:dd:228c/1282c19:dd:c25:c25d:dd:dd:dd:228c
1422c19:dd:c25:c25d:dd:dd:dd:228d/1282c19:dd:c25:c25d:dd:dd:dd:228d
1432c19:dd:c25:c25d:dd:dd:dd:228e/1282c19:dd:c25:c25d:dd:dd:dd:228e
1442c19:dd:c25:c25d:dd:dd:dd:228f/1282c19:dd:c25:c25d:dd:dd:dd:228f
1452c19:dd:c25:c25d:dd:dd:dd:2290/1282c19:dd:c25:c25d:dd:dd:dd:2290
1462c19:dd:c25:c25d:dd:dd:dd:2291/1282c19:dd:c25:c25d:dd:dd:dd:2291
1472c19:dd:c25:c25d:dd:dd:dd:2292/1282c19:dd:c25:c25d:dd:dd:dd:2292
1482c19:dd:c25:c25d:dd:dd:dd:2293/1282c19:dd:c25:c25d:dd:dd:dd:2293
1492c19:dd:c25:c25d:dd:dd:dd:2294/1282c19:dd:c25:c25d:dd:dd:dd:2294
1502c19:dd:c25:c25d:dd:dd:dd:2295/1282c19:dd:c25:c25d:dd:dd:dd:2295
1512c19:dd:c25:c25d:dd:dd:dd:2296/1282c19:dd:c25:c25d:dd:dd:dd:2296
1522c19:dd:c25:c25d:dd:dd:dd:2297/1282c19:dd:c25:c25d:dd:dd:dd:2297
1532c19:dd:c25:c25d:dd:dd:dd:2298/1282c19:dd:c25:c25d:dd:dd:dd:2298
1542c19:dd:c25:c25d:dd:dd:dd:2299/1282c19:dd:c25:c25d:dd:dd:dd:2299
1552c19:dd:c25:c25d:dd:dd:dd:229a/1282c19:dd:c25:c25d:dd:dd:dd:229a
1562c19:dd:c25:c25d:dd:dd:dd:229b/1282c19:dd:c25:c25d:dd:dd:dd:229b
1572c19:dd:c25:c25d:dd:dd:dd:229c/1282c19:dd:c25:c25d:dd:dd:dd:229c
1582c19:dd:c25:c25d:dd:dd:dd:229d/1282c19:dd:c25:c25d:dd:dd:dd:229d
1592c19:dd:c25:c25d:dd:dd:dd:229e/1282c19:dd:c25:c25d:dd:dd:dd:229e
1602c19:dd:c25:c25d:dd:dd:dd:229f/1282c19:dd:c25:c25d:dd:dd:dd:229f
1612c19:dd:c25:c25d:dd:dd:dd:22a0/1282c19:dd:c25:c25d:dd:dd:dd:22a0
1622c19:dd:c25:c25d:dd:dd:dd:22a1/1282c19:dd:c25:c25d:dd:dd:dd:22a1
1632c19:dd:c25:c25d:dd:dd:dd:22a2/1282c19:dd:c25:c25d:dd:dd:dd:22a2
1642c19:dd:c25:c25d:dd:dd:dd:22a3/1282c19:dd:c25:c25d:dd:dd:dd:22a3
1652c19:dd:c25:c25d:dd:dd:dd:22a4/1282c19:dd:c25:c25d:dd:dd:dd:22a4
1662c19:dd:c25:c25d:dd:dd:dd:22a5/1282c19:dd:c25:c25d:dd:dd:dd:22a5
1672c19:dd:c25:c25d:dd:dd:dd:22a6/1282c19:dd:c25:c25d:dd:dd:dd:22a6
1682c19:dd:c25:c25d:dd:dd:dd:22a7/1282c19:dd:c25:c25d:dd:dd:dd:22a7
1692c19:dd:c25:c25d:dd:dd:dd:22a8/1282c19:dd:c25:c25d:dd:dd:dd:22a8
1702c19:dd:c25:c25d:dd:dd:dd:22a9/1282c19:dd:c25:c25d:dd:dd:dd:22a9
1712c19:dd:c25:c25d:dd:dd:dd:22aa/1282c19:dd:c25:c25d:dd:dd:dd:22aa
1722c19:dd:c25:c25d:dd:dd:dd:22ab/1282c19:dd:c25:c25d:dd:dd:dd:22ab
1732c19:dd:c25:c25d:dd:dd:dd:22ac/1282c19:dd:c25:c25d:dd:dd:dd:22ac
1742c19:dd:c25:c25d:dd:dd:dd:22ad/1282c19:dd:c25:c25d:dd:dd:dd:22ad
1752c19:dd:c25:c25d:dd:dd:dd:22ae/1282c19:dd:c25:c25d:dd:dd:dd:22ae
1762c19:dd:c25:c25d:dd:dd:dd:22af/1282c19:dd:c25:c25d:dd:dd:dd:22af
1772c19:dd:c25:c25d:dd:dd:dd:22b0/1282c19:dd:c25:c25d:dd:dd:dd:22b0
1782c19:dd:c25:c25d:dd:dd:dd:22b1/1282c19:dd:c25:c25d:dd:dd:dd:22b1
1792c19:dd:c25:c25d:dd:dd:dd:22b2/1282c19:dd:c25:c25d:dd:dd:dd:22b2
1802c19:dd:c25:c25d:dd:dd:dd:22b3/1282c19:dd:c25:c25d:dd:dd:dd:22b3
1812c19:dd:c25:c25d:dd:dd:dd:22b4/1282c19:dd:c25:c25d:dd:dd:dd:22b4
1822c19:dd:c25:c25d:dd:dd:dd:22b5/1282c19:dd:c25:c25d:dd:dd:dd:22b5
1832c19:dd:c25:c25d:dd:dd:dd:22b6/1282c19:dd:c25:c25d:dd:dd:dd:22b6
1842c19:dd:c25:c25d:dd:dd:dd:22b7/1282c19:dd:c25:c25d:dd:dd:dd:22b7
1852c19:dd:c25:c25d:dd:dd:dd:22b8/1282c19:dd:c25:c25d:dd:dd:dd:22b8
1862c19:dd:c25:c25d:dd:dd:dd:22b9/1282c19:dd:c25:c25d:dd:dd:dd:22b9
1872c19:dd:c25:c25d:dd:dd:dd:22ba/1282c19:dd:c25:c25d:dd:dd:dd:22ba
1882c19:dd:c25:c25d:dd:dd:dd:22bb/1282c19:dd:c25:c25d:dd:dd:dd:22bb
1892c19:dd:c25:c25d:dd:dd:dd:22bc/1282c19:dd:c25:c25d:dd:dd:dd:22bc
1902c19:dd:c25:c25d:dd:dd:dd:22bd/1282c19:dd:c25:c25d:dd:dd:dd:22bd
1912c19:dd:c25:c25d:dd:dd:dd:22be/1282c19:dd:c25:c25d:dd:dd:dd:22be
1922c19:dd:c25:c25d:dd:dd:dd:22bf/1282c19:dd:c25:c25d:dd:dd:dd:22bf
1932c19:dd:c25:c25d:dd:dd:dd:22c0/1282c19:dd:c25:c25d:dd:dd:dd:22c0
1942c19:dd:c25:c25d:dd:dd:dd:22c1/1282c19:dd:c25:c25d:dd:dd:dd:22c1
1952c19:dd:c25:c25d:dd:dd:dd:22c2/1282c19:dd:c25:c25d:dd:dd:dd:22c2
1962c19:dd:c25:c25d:dd:dd:dd:22c3/1282c19:dd:c25:c25d:dd:dd:dd:22c3
1972c19:dd:c25:c25d:dd:dd:dd:22c4/1282c19:dd:c25:c25d:dd:dd:dd:22c4
1982c19:dd:c25:c25d:dd:dd:dd:22c5/1282c19:dd:c25:c25d:dd:dd:dd:22c5
1992c19:dd:c25:c25d:dd:dd:dd:22c6/1282c19:dd:c25:c25d:dd:dd:dd:22c6
2002c19:dd:c25:c25d:dd:dd:dd:22c7/1282c19:dd:c25:c25d:dd:dd:dd:22c7
2012c19:dd:c25:c25d:dd:dd:dd:22c8/1282c19:dd:c25:c25d:dd:dd:dd:22c8
2022c19:dd:c25:c25d:dd:dd:dd:22c9/1282c19:dd:c25:c25d:dd:dd:dd:22c9
2032c19:dd:c25:c25d:dd:dd:dd:22ca/1282c19:dd:c25:c25d:dd:dd:dd:22ca
2042c19:dd:c25:c25d:dd:dd:dd:22cb/1282c19:dd:c25:c25d:dd:dd:dd:22cb
2052c19:dd:c25:c25d:dd:dd:dd:22cc/1282c19:dd:c25:c25d:dd:dd:dd:22cc
2062c19:dd:c25:c25d:dd:dd:dd:22cd/1282c19:dd:c25:c25d:dd:dd:dd:22cd
2072c19:dd:c25:c25d:dd:dd:dd:22ce/1282c19:dd:c25:c25d:dd:dd:dd:22ce
2082c19:dd:c25:c25d:dd:dd:dd:22cf/1282c19:dd:c25:c25d:dd:dd:dd:22cf
2092c19:dd:c25:c25d:dd:dd:dd:22d0/1282c19:dd:c25:c25d:dd:dd:dd:22d0
2102c19:dd:c25:c25d:dd:dd:dd:22d1/1282c19:dd:c25:c25d:dd:dd:dd:22d1
2112c19:dd:c25:c25d:dd:dd:dd:22d2/1282c19:dd:c25:c25d:dd:dd:dd:22d2
2122c19:dd:c25:c25d:dd:dd:dd:22d3/1282c19:dd:c25:c25d:dd:dd:dd:22d3
2132c19:dd:c25:c25d:dd:dd:dd:22d4/1282c19:dd:c25:c25d:dd:dd:dd:22d4
2142c19:dd:c25:c25d:dd:dd:dd:22d5/1282c19:dd:c25:c25d:dd:dd:dd:22d5
2152c19:dd:c25:c25d:dd:dd:dd:22d6/1282c19:dd:c25:c25d:dd:dd:dd:22d6
2162c19:dd:c25:c25d:dd:dd:dd:22d7/1282c19:dd:c25:c25d:dd:dd:dd:22d7
2172c19:dd:c25:c25d:dd:dd:dd:22d8/1282c19:dd:c25:c25d:dd:dd:dd:22d8
2182c19:dd:c25:c25d:dd:dd:dd:22d9/1282c19:dd:c25:c25d:dd:dd:dd:22d9
2192c19:dd:c25:c25d:dd:dd:dd:22da/1282c19:dd:c25:c25d:dd:dd:dd:22da
2202c19:dd:c25:c25d:dd:dd:dd:22db/1282c19:dd:c25:c25d:dd:dd:dd:22db
2212c19:dd:c25:c25d:dd:dd:dd:22dc/1282c19:dd:c25:c25d:dd:dd:dd:22dc
2222c19:dd:c25:c25d:dd:dd:dd:22dd/1282c19:dd:c25:c25d:dd:dd:dd:22dd
2232c19:dd:c25:c25d:dd:dd:dd:22de/1282c19:dd:c25:c25d:dd:dd:dd:22de
2242c19:dd:c25:c25d:dd:dd:dd:22df/1282c19:dd:c25:c25d:dd:dd:dd:22df
2252c19:dd:c25:c25d:dd:dd:dd:22e0/1282c19:dd:c25:c25d:dd:dd:dd:22e0
2262c19:dd:c25:c25d:dd:dd:dd:22e1/1282c19:dd:c25:c25d:dd:dd:dd:22e1
2272c19:dd:c25:c25d:dd:dd:dd:22e2/1282c19:dd:c25:c25d:dd:dd:dd:22e2
2282c19:dd:c25:c25d:dd:dd:dd:22e3/1282c19:dd:c25:c25d:dd:dd:dd:22e3
2292c19:dd:c25:c25d:dd:dd:dd:22e4/1282c19:dd:c25:c25d:dd:dd:dd:22e4
2302c19:dd:c25:c25d:dd:dd:dd:22e5/1282c19:dd:c25:c25d:dd:dd:dd:22e5
2312c19:dd:c25:c25d:dd:dd:dd:22e6/1282c19:dd:c25:c25d:dd:dd:dd:22e6
2322c19:dd:c25:c25d:dd:dd:dd:22e7/1282c19:dd:c25:c25d:dd:dd:dd:22e7
2332c19:dd:c25:c25d:dd:dd:dd:22e8/1282c19:dd:c25:c25d:dd:dd:dd:22e8
2342c19:dd:c25:c25d:dd:dd:dd:22e9/1282c19:dd:c25:c25d:dd:dd:dd:22e9
2352c19:dd:c25:c25d:dd:dd:dd:22ea/1282c19:dd:c25:c25d:dd:dd:dd:22ea
2362c19:dd:c25:c25d:dd:dd:dd:22eb/1282c19:dd:c25:c25d:dd:dd:dd:22eb
2372c19:dd:c25:c25d:dd:dd:dd:22ec/1282c19:dd:c25:c25d:dd:dd:dd:22ec
2382c19:dd:c25:c25d:dd:dd:dd:22ed/1282c19:dd:c25:c25d:dd:dd:dd:22ed
2392c19:dd:c25:c25d:dd:dd:dd:22ee/1282c19:dd:c25:c25d:dd:dd:dd:22ee
2402c19:dd:c25:c25d:dd:dd:dd:22ef/1282c19:dd:c25:c25d:dd:dd:dd:22ef
2412c19:dd:c25:c25d:dd:dd:dd:22f0/1282c19:dd:c25:c25d:dd:dd:dd:22f0
2422c19:dd:c25:c25d:dd:dd:dd:22f1/1282c19:dd:c25:c25d:dd:dd:dd:22f1
2432c19:dd:c25:c25d:dd:dd:dd:22f2/1282c19:dd:c25:c25d:dd:dd:dd:22f2
2442c19:dd:c25:c25d:dd:dd:dd:22f3/1282c19:dd:c25:c25d:dd:dd:dd:22f3
2452c19:dd:c25:c25d:dd:dd:dd:22f4/1282c19:dd:c25:c25d:dd:dd:dd:22f4
2462c19:dd:c25:c25d:dd:dd:dd:22f5/1282c19:dd:c25:c25d:dd:dd:dd:22f5
2472c19:dd:c25:c25d:dd:dd:dd:22f6/1282c19:dd:c25:c25d:dd:dd:dd:22f6
2482c19:dd:c25:c25d:dd:dd:dd:22f7/1282c19:dd:c25:c25d:dd:dd:dd:22f7
2492c19:dd:c25:c25d:dd:dd:dd:22f8/1282c19:dd:c25:c25d:dd:dd:dd:22f8
2502c19:dd:c25:c25d:dd:dd:dd:22f9/1282c19:dd:c25:c25d:dd:dd:dd:22f9
2512c19:dd:c25:c25d:dd:dd:dd:22fa/1282c19:dd:c25:c25d:dd:dd:dd:22fa
2522c19:dd:c25:c25d:dd:dd:dd:22fb/1282c19:dd:c25:c25d:dd:dd:dd:22fb
2532c19:dd:c25:c25d:dd:dd:dd:22fc/1282c19:dd:c25:c25d:dd:dd:dd:22fc
2542c19:dd:c25:c25d:dd:dd:dd:22fd/1282c19:dd:c25:c25d:dd:dd:dd:22fd
2552c19:dd:c25:c25d:dd:dd:dd:22fe/1282c19:dd:c25:c25d:dd:dd:dd:22fe
2562c19:dd:c25:c25d:dd:dd:dd:22ff/1282c19:dd:c25:c25d:dd:dd:dd:22ff

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.