Bitmand

Networking

IPv4 Subnets

Amount of usable addresses in a subnet, is 2 less than total addresses.

CIDR Addresses Netmask Size Comparison Comment
/32 1 255.255.255.255 1/256 of /24 A single host
/31 2 255.255.255.254 1/128 of /24 Useless due to 0 usable addresses
/30 4 255.255.255.252 1/64 of /24  
/29 8 255.255.255.248 1/32 of /24  
/28 16 255.255.255.240 1/16 of /24  
/27 32 255.255.255.224 1/8 of /24  
/26 64 255.255.255.192 1/4 of /24  
/25 128 255.255.255.128 1/2 of /24  
/24 256 255.255.255.0 1 x /24 Class C
/23 512 255.255.254.0 2 x /24  
/22 1.024 255.255.252.0 4 x /24  
/21 2.048 255.255.248.0 8 x /24  
/20 4.096 255.255.240.0 16 x /24  
/19 8.192 255.255.224.0 32 x /24  
/18 16.384 255.255.192.0 64 x /24  
/17 32.768 255.255.128.0 128 x /24  
/16 65.536 255.255.0.0 256 x /24 Class B
/15 131.072 255.254.0.0 2 x /16  
/14 262.144 255.252.0.0 4 x /16  
/13 524.288 255.248.0.0 8 x /16  
/12 1.048.576 255.240.0.0 16 x /16  
/11 2.097.152 255.224.0.0 32 x /16  
/10 4.194.304 255.192.0.0 64 x /16  
/9 8.388.608 255.128.0.0 128 x /16  
/8 16.777.216 255.0.0.0 256 x /16 Class A
/7 33.554.432 254.0.0.0 2 x /8  
/6 67.108.864 252.0.0.0 4 x /8  
/5 268.435.456 248.0.0.0 8 x /8  
/4 268.435.456 240.0.0.0 16 x /8  
/3 536.870.912 224.0.0.0 32 x /8  
/2 1.073.741.824 192.0.0.0 64 x /8  
/1 2.147.483.648 128.0.0.0 128 x /8  
/0 4.294.967.296 0.0.0.0 256 x /8  

IPv4 Subnet Guide

Subnet Network From To Broadcast Total Usable
/24 .0 .1 .254 .255 256 254
Subnet Network From To Broadcast Total Usable
/25 .0 .1 .126 .127 128 126
/25 .128 .129 .254 .255 128 126
Subnet Network From To Broadcast Total Usable
/26 .0 .1 .62 .63 64 62
/26 .64 .65 .126 .127 64 62
/26 .128 .129 .190 .191 64 62
/26 .192 .193 .254 .255 64 62
Subnet Network From To Broadcast Total Usable
/27 .0 .1 .30 .31 32 30
/27 .32 .33 .62 .63 32 30
/27 .64 .65 .94 .95 32 30
/27 .96 .97 .126 .127 32 30
/27 .128 .129 .158 .159 32 30
/27 .160 .161 .190 .191 32 30
/27 .192 .193 .222 .223 32 30
/27 .224 .225 .254 .255 32 30
Subnet Network From To Broadcast Total Usable
/28 .0 .1 .14 .15 16 14
/28 .16 .17 .30 .31 16 14
/28 .32 .33 .46 .47 16 14
/28 .48 .49 .62 .63 16 14
/28 .64 .65 .78 .79 16 14
/28 .80 .81 .94 .95 16 14
/28 .96 .97 .110 .111 16 14
/28 .112 .113 .126 .127 16 14
/28 .128 .129 .142 .143 16 14
/28 .144 .145 .158 .159 16 14
/28 .160 .161 .174 .175 16 14
/28 .176 .177 .190 .191 16 14
/28 .192 .193 .206 .207 16 14
/28 .208 .209 .222 .223 16 14
/28 .224 .225 .238 .239 16 14
/28 .240 .241 .254 .255 16 14
Subnet Network From To Broadcast Total Usable
/29 .0 .1 .6 .7 8 6
/29 .8 .9 .14 .15 8 6
/29 .16 .17 .22 .23 8 6
/29 .24 .25 .30 .31 8 6
/29 .32 .33 .38 .39 8 6
/29 .40 .41 .46 .47 8 6
/29 .48 .49 .54 .55 8 6
/29 .56 .57 .62 .63 8 6
/29 .64 .65 .70 .71 8 6
/29 .72 .73 .78 .79 8 6
/29 .80 .81 .86 .87 8 6
/29 .88 .89 .94 .95 8 6
/29 .96 .97 .102 .103 8 6
/29 .104 .105 .110 .111 8 6
/29 .112 .113 .118 .119 8 6
/29 .120 .121 .126 .127 8 6
/29 .128 .129 .134 .135 8 6
/29 .136 .137 .142 .143 8 6
/29 .144 .145 .150 .151 8 6
/29 .152 .153 .158 .159 8 6
/29 .160 .161 .166 .167 8 6
/29 .168 .169 .174 .175 8 6
/29 .176 .177 .182 .183 8 6
/29 .184 .185 .190 .191 8 6
/29 .192 .193 .198 .199 8 6
/29 .200 .201 .206 .207 8 6
/29 .208 .209 .214 .215 8 6
/29 .216 .217 .222 .223 8 6
/29 .224 .225 .230 .231 8 6
/29 .232 .233 .238 .239 8 6
/29 .240 .241 .246 .247 8 6
/29 .248 .249 .254 .255 8 6
Subnet Network From To Broadcast Total Usable
/30 .0 .1 .2 .3 4 2
/30 .4 .5 .6 .7 4 2
/30 .8 .9 .10 .11 4 2
/30 .12 .13 .14 .15 4 2
/30 .16 .17 .18 .19 4 2
/30 .20 .21 .22 .23 4 2
/30 .24 .25 .26 .27 4 2
/30 .28 .29 .30 .31 4 2
/30 .32 .33 .34 .35 4 2
/30 .36 .37 .38 .39 4 2
/30 .40 .41 .42 .43 4 2
/30 .44 .45 .46 .47 4 2
/30 .48 .49 .50 .51 4 2
/30 .52 .53 .54 .55 4 2
/30 .56 .57 .58 .59 4 2
/30 .60 .61 .62 .63 4 2
/30 .64 .65 .66 .67 4 2
/30 .68 .69 .70 .71 4 2
/30 .72 .73 .74 .75 4 2
/30 .76 .77 .78 .79 4 2
/30 .80 .81 .82 .83 4 2
/30 .84 .85 .86 .87 4 2
/30 .88 .89 .90 .91 4 2
/30 .92 .93 .94 .95 4 2
/30 .96 .97 .98 .99 4 2
/30 .100 .101 .102 .103 4 2
/30 .104 .105 .106 .107 4 2
/30 .108 .109 .110 .111 4 2
/30 .112 .113 .114 .115 4 2
/30 .116 .117 .118 .119 4 2
/30 .120 .121 .122 .123 4 2
/30 .124 .125 .126 .127 4 2
/30 .128 .129 .130 .131 4 2
/30 .132 .133 .134 .135 4 2
/30 .136 .137 .138 .139 4 2
/30 .140 .141 .142 .143 4 2
/30 .144 .145 .146 .147 4 2
/30 .148 .149 .150 .151 4 2
/30 .152 .153 .154 .155 4 2
/30 .156 .157 .158 .159 4 2
/30 .160 .161 .162 .163 4 2
/30 .164 .165 .166 .167 4 2
/30 .168 .169 .170 .171 4 2
/30 .172 .173 .174 .175 4 2
/30 .176 .177 .178 .179 4 2
/30 .180 .181 .182 .183 4 2
/30 .184 .185 .186 .187 4 2
/30 .188 .189 .190 .191 4 2
/30 .192 .193 .194 .195 4 2
/30 .196 .197 .198 .199 4 2
/30 .200 .201 .202 .203 4 2
/30 .204 .205 .206 .207 4 2
/30 .208 .209 .210 .211 4 2
/30 .212 .213 .214 .215 4 2
/30 .216 .217 .218 .219 4 2
/30 .220 .221 .222 .223 4 2
/30 .224 .225 .226 .227 4 2
/30 .228 .229 .230 .231 4 2
/30 .232 .233 .234 .235 4 2
/30 .236 .237 .238 .239 4 2
/30 .240 .241 .242 .243 4 2
/30 .244 .245 .246 .247 4 2
/30 .248 .249 .250 .251 4 2
/30 .252 .253 .254 .255 4 2

IPv4 Reserved Networks

Name Network Range IETF RFC
localhost 127.0.0.0/8 127.0.0.0 - 127.255.255.255 RFC5735
Private Network 10.0.0.0/8 10.0.0.0 - 10.255.255.255 RFC1918
Private Network 172.16.0.0/12 172.16.0.0 - 172.31.255.255 RFC1918
Private Network 192.168.0.0/16 192.168.0.0 - 192.168.255.255 RFC1918

IPv6 Address Scopes

IPv6 Address Scope Description
::/128 unspecified address
::1/128 localhost
fe80::/10 link local
fc00::/7 unique local unicast (RFC 4193)
ff00::/8 multicast, following after the prefix ff there are 4 bits for flags and 4 bits for the scope
::ffff:0:0/96 ipv4 to ipv6 address, eg: ::ffff:10.10.10.10 (RFC 4038)
2000::/3 global unicast
2001::/16 /32 subnets assigned to providers, they assign /48, /56 or /64 to the customer
2001:db8::/32 reserved for use in documentation
2001:678::/29 provider independent (PI) adresses and anycasting TLD nameservers
2002::/16 6to4 scope, 2002:c058:6301:: is the 6to4 public router anycast (RFC 3068)

IPv6 Subnet Prefix Lengths 

2402:9400:0000:0000:0000:0000:0000:0001
XXXX:XXXX:XXXX:XXXX:XXXX:XXXX:XXXX:XXXX
      ||| |||| |||| |||| |||| |||| ||||
      ||| |||| |||| |||| |||| |||| |||128
      ||| |||| |||| |||| |||| |||| ||124
      ||| |||| |||| |||| |||| |||| |120
      ||| |||| |||| |||| |||| |||| 116
      ||| |||| |||| |||| |||| |||112
      ||| |||| |||| |||| |||| ||108
      ||| |||| |||| |||| |||| |104
      ||| |||| |||| |||| |||| 100
      ||| |||| |||| |||| |||96
      ||| |||| |||| |||| ||92
      ||| |||| |||| |||| |88
      ||| |||| |||| |||| 84
      ||| |||| |||| |||80
      ||| |||| |||| ||76
      ||| |||| |||| |72
      ||| |||| |||| 68
      ||| |||| |||64
      ||| |||| ||60
      ||| |||| |56
      ||| |||| 52
      ||| |||48
      ||| ||44
      ||| |40
      ||| 36
      ||32
      |28
      24

IPv6 Subnet Sizes

IPv6 CIDR Subnet Number of IPs
/128 1
/127 2
/126 4
/125 8
/124 16
/123 32
/122 64
/121 128
/120 256
/119 512
/118 1,024
/117 2,048
/116 4,096
/115 8,192
/114 16,384
/113 32,768
/112 65,536
/111 131,072
/110 262,144
/109 524,288
/108 1,048,576
/107 2,097,152
/106 4,194,304
/105 8,388,608
/104 16,777,216
/103 33,554,432
/102 67,108,864
/101 134,217,728
/100 268,435,456
/99 536,870,912
/98 1,073,741,824
/97 2,147,483,648
/96 4,294,967,296
/95 8,589,934,592
/94 17,179,869,184
/93 34,359,738,368
/92 68,719,476,736
/91 137,438,953,472
/90 274,877,906,944
/89 549,755,813,888
/88 1,099,511,627,776
/87 2,199,023,255,552
/86 4,398,046,511,104
/85 8,796,093,022,208
/84 17,592,186,044,416
/83 35,184,372,088,832
/82 70,368,744,177,664
/81 140,737,488,355,328
/80 281,474,976,710,656
/79 562,949,953,421,312
/78 1,125,899,906,842,624
/77 2,251,799,813,685,248
/76 4,503,599,627,370,496
/75 9,007,199,254,740,992
/74 18,014,398,509,481,985
/73 36,028,797,018,963,968
/72 72,057,594,037,927,936
/71 144,115,188,075,855,872
/70 288,230,376,151,711,744
/69 576,460,752,303,423,488
/68 1,152,921,504,606,846,976
/67 2,305,843,009,213,693,952
/66 4,611,686,018,427,387,904
/65 9,223,372,036,854,775,808
Residential: /64 18,446,744,073,709,551,616
/63 36,893,488,147,419,103,232
/62 73,786,976,294,838,206,464
/61 147,573,952,589,676,412,928
/60 295,147,905,179,352,825,856
/59 590,295,810,358,705,651,712
/58 1,180,591,620,717,411,303,424
/57 2,361,183,241,434,822,606,848
/56 4,722,366,482,869,645,213,696
/55 9,444,732,965,739,290,427,392
/54 18,889,465,931,478,580,854,784
/53 37,778,931,862,957,161,709,568
/52 75,557,863,725,914,323,419,136
/51 151,115,727,451,828,646,838,272
/50 302,231,454,903,657,293,676,544
/49 604,462,909,807,314,587,353,088
Business: /48 1,208,925,819,614,629,174,706,176
/47 2,417,851,639,229,258,349,412,352
/46 4,835,703,278,458,516,698,824,704
/45 9,671,406,556,917,033,397,649,408
/44 19,342,813,113,834,066,795,298,816
/43 38,685,626,227,668,133,590,597,632
/42 77,371,252,455,336,267,181,195,264
/41 154,742,504,910,672,534,362,390,528
/40 309,485,009,821,345,068,724,781,056
/39 618,970,019,642,690,137,449,562,112
/38 1,237,940,039,285,380,274,899,124,224
/37 2,475,880,078,570,760,549,798,248,448
/36 4,951,760,157,141,521,099,596,496,896
/35 9,903,520,314,283,042,199,192,993,792
/34 19,807,040,628,566,084,398,385,987,584
/33 39,614,081,257,132,168,796,771,975,168
ISP: /32 79,228,162,514,264,337,593,543,950,336
/31 158,456,325,028,528,675,187,087,900,672
/30 316,912,650,057,057,350,374,175,801,344
/29 633,825,300,114,114,700,748,351,602,688
/28 1,267,650,600,228,229,401,496,703,205,376
/27 2,535,301,200,456,458,802,993,406,410,752
/26 5,070,602,400,912,917,605,986,812,821,504
/25 10,141,204,801,825,835,211,973,625,643,008
/24 20,282,409,603,651,670,423,947,251,286,016
/23 40,564,819,207,303,340,847,894,502,572,032
/22 81,129,638,414,606,681,695,789,005,144,064
/21 162,259,276,829,213,363,391,578,010,288,128
/20 324,518,553,658,426,726,783,156,020,576,256
/19 649,037,107,316,853,453,566,312,041,152,512
/18 1,298,074,214,633,706,907,132,624,082,305,024
/17 2,596,148,429,267,413,814,265,248,164,610,048
/16 5,192,296,858,534,827,628,530,496,329,220,096
/15 10,384,593,717,069,655,257,060,992,658,440,192
/14 20,769,187,434,139,310,514,121,985,316,880,384
/13 41,538,374,868,278,621,028,243,970,633,760,768
/12 83,076,749,736,557,242,056,487,941,267,521,536
/11 166,153,499,473,114,484,112,975,882,535,043,072
/10 332,306,998,946,228,968,225,951,765,070,086,144
/9 664,613,997,892,457,936,451,903,530,140,172,288
/8 1,329,227,995,784,915,872,903,807,060,280,344,576

...self-proclaimed Internet Enthusiast!