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
IETF RFC5735: Special Use IPv4 Addresses
IETF RFC1918: Address Allocation for Private Internets
ipv4 subnets
CIDR | Addresses | Netmask | Size | Comment
---- | ------------- | --------------- | --------------- | -------
/32 | 1 | 255.255.255.255 | 1/256 of /24 | A single host
/31 | 2 | 255.255.255.254 | 1/128 of /24 | 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 |
Amount of **usable addresses** in a subnet, is 2 less than total addresses.
IETF RFC1878: Variable Length Subnet Table For IPv4
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