Subnetting
List of IPv4 and IPv6 ranges, subnet size tables and special address types
Calculate subnet masks
ipcalc 10.0.0.1/22 -s 254 254 254 254
IPv4 ranges
| Scope | Class | First | Last | Netmask |
|---|---|---|---|---|
| Public | A | 1.0.0.0 | 126.255.255.255 | 255.0.0.0 |
| Public | B | 128.0.0.0 | 192.255.0.0 | 255.255.0.0 |
| Public | C | 192.0.0.0 | 223.255.255.0 | 255.255.255.0 |
| Public | D | 224.0.0.0 | 239.255.255.255 | |
| Public | E | 240.0.0.0 | 255.255.255.255 | |
| Private | A | 10.0.0.0 | 10.255.255.255 | 255.0.0.0 |
| Private | B | 172.16.0.0 | 172.31.255.255 | 255.255.0.0 |
| Private | C | 192.168.0.0 | 192.168.255.255 | 255.255.255.0 |
Special address types
| Type | CIDR | IPv4 | IPv6 |
|---|---|---|---|
| Default | 0.0.0.0/0 | 0.0.0.0 | :: |
| Loopback (localhost) | 127.0.0.0/8 | 127.0.0.1 - 127.255.255.254 | ::1 |
| Link-local | 169.254.0.0/16 | 169.254.0.1 - 169.254.255.254 | FE80::/64 |
| Global broadcast | 255.255.255.255 | using multicast | |
| Multicast | 224.0.0.0/4 | 224.0.0.0 - 224.0.0.255 | FF00::/8 |
| Unique Local Unicast | FC00::/7 FD00::/8 |
IPv6 Anycast
Routers direct packets addressed to this destination to the location nearest the sender
Anycast-addresses may have any random prefix and are formally indistinguishable from unicast addresses
IPv4 subnet sizes
| IPv4 CIDR mask | Dotted decimal mask | Amount of usable host addresses |
|---|---|---|
| /1 | 128.0.0.0 | 2147483646 |
| /2 | 192.0.0.0 | 1073741822 |
| /3 | 224.0.0.0 | 536870910 |
| /4 | 240.0.0.0 | 268435454 |
| /5 | 248.0.0.0 | 134217726 |
| /6 | 252.0.0.0 | 67108862 |
| /7 | 254.0.0.0 | 33554430 |
| /8 | 255.0.0.0 | 16777214 |
| /9 | 255.128.0.0 | 8388606 |
| /10 | 255.192.0.0 | 4194302 |
| /11 | 255.224.0.0 | 2097150 |
| /12 | 255.240.0.0 | 1048574 |
| /13 | 255.248.0.0 | 524286 |
| /14 | 255.252.0.0 | 262142 |
| /15 | 255.254.0.0 | 131070 |
| /16 | 255.255.0.0 | 65534 |
| /17 | 255.255.128.0 | 32766 |
| /18 | 255.255.192.0 | 16382 |
| /19 | 255.255.224.0 | 8190 |
| /20 | 255.255.240.0 | 4094 |
| /21 | 255.255.248.0 | 2046 |
| /22 | 255.255.252.0 | 1022 |
| /23 | 255.255.254.0 | 510 |
| /24 | 255.255.255.0 | 254 |
| /25 | 255.255.255.128 | 126 |
| /26 | 255.255.255.192 | 62 |
| /27 | 255.255.255.224 | 30 |
| /28 | 255.255.255.240 | 14 |
| /29 | 255.255.255.248 | 6 |
| /30 | 255.255.255.252 | 2 |
| /31 | 255.255.255.254 | no net, 2 hosts |
| /32 | 255.255.255.255 | no net, one host |
IPv6 subnet sizes
| IPv6 CIDR mask | Amount of networks or addresses |
|---|---|
| /1 | 9223372036854775808 networks of size /64 |
| /2 | 4611686018427387904 networks of size /64 |
| /3 | 2305843009213693952 networks of size /64 |
| /4 | 1152921504606846976 networks of size /64 |
| /5 | 576460752303423488 networks of size /64 |
| /6 | 288230376151711744 networks of size /64 |
| /7 | 144115188075855872 networks of size /64 |
| /8 | 72057594037927936 networks of size /64 |
| /9 | 36028797018963968 networks of size /64 |
| /10 | 18014398509481984 networks of size /64 |
| /11 | 9007199254740992 networks of size /64 |
| /12 | 4503599627370496 networks of size /64 |
| /13 | 2251799813685248 networks of size /64 |
| /14 | 1125899906842624 networks of size /64 |
| /15 | 562949953421312 networks of size /64 |
| /16 | 281474976710656 networks of size /64 |
| /17 | 140737488355328 networks of size /64 |
| /18 | 70368744177664 networks of size /64 |
| /19 | 35184372088832 networks of size /64 |
| /20 | 17592186044416 networks of size /64 |
| /21 | 8796093022208 networks of size /64 |
| /22 | 4398046511104 networks of size /64 |
| /23 | 2199023255552 networks of size /64 |
| /24 | 1099511627776 networks of size /64 |
| /25 | 549755813888 networks of size /64 |
| /26 | 274877906944 networks of size /64 |
| /27 | 137438953472 networks of size /64 |
| /28 | 68719476736 networks of size /64 |
| /29 | 34359738368 networks of size /64 |
| /30 | 17179869184 networks of size /64 |
| /31 | 8589934592 networks of size /64 |
| /32 | 4294967296 networks of size /64 |
| /33 | 2147483648 networks of size /64 |
| /34 | 1073741824 networks of size /64 |
| /35 | 536870912 networks of size /64 |
| /36 | 268435456 networks of size /64 |
| /37 | 134217728 networks of size /64 |
| /38 | 67108864 networks of size /64 |
| /39 | 33554432 networks of size /64 |
| /40 | 16777216 networks of size /64 |
| /41 | 8388608 networks of size /64 |
| /42 | 4194304 networks of size /64 |
| /43 | 2097152 networks of size /64 |
| /44 | 1048576 networks of size /64 |
| /45 | 524288 networks of size /64 |
| /46 | 262144 networks of size /64 |
| /47 | 131072 networks of size /64 |
| /48 | 65536 networks of size /64 |
| /49 | 32768 networks of size /64 |
| /50 | 16384 networks of size /64 |
| /51 | 8192 networks of size /64 |
| /52 | 4096 networks of size /64 |
| /53 | 2048 networks of size /64 |
| /54 | 1024 networks of size /64 |
| /55 | 512 networks of size /64 |
| /56 | 256 networks of size /64 |
| /57 | 128 networks of size /64 |
| /58 | 64 networks of size /64 |
| /59 | 32 networks of size /64 |
| /60 | 16 networks of size /64 |
| /61 | 8 networks of size /64 |
| /62 | 4 networks of size /64 |
| /63 | 2 networks of size /64 |
| /64 | 18446744073709551616 addresses |
| /65 | 9223372036854775808 addresses |
| /66 | 4611686018427387904 addresses |
| /67 | 2305843009213693952 addresses |
| /68 | 1152921504606846976 addresses |
| /69 | 576460752303423488 addresses |
| /70 | 288230376151711744 addresses |
| /71 | 144115188075855872 addresses |
| /72 | 72057594037927936 addresses |
| /73 | 36028797018963968 addresses |
| /74 | 18014398509481984 addresses |
| /75 | 9007199254740992 addresses |
| /76 | 4503599627370496 addresses |
| /77 | 2251799813685248 addresses |
| /78 | 1125899906842624 addresses |
| /79 | 562949953421312 addresses |
| /80 | 281474976710656 addresses |
| /81 | 140737488355328 addresses |
| /82 | 70368744177664 addresses |
| /83 | 35184372088832 addresses |
| /84 | 17592186044416 addresses |
| /85 | 8796093022208 addresses |
| /86 | 4398046511104 addresses |
| /87 | 2199023255552 addresses |
| /88 | 1099511627776 addresses |
| /89 | 549755813888 addresses |
| /90 | 274877906944 addresses |
| /91 | 137438953472 addresses |
| /92 | 68719476736 addresses |
| /93 | 34359738368 addresses |
| /94 | 17179869184 addresses |
| /95 | 8589934592 addresses |
| /96 | 4294967296 addresses |
| /97 | 2147483648 addresses |
| /98 | 1073741824 addresses |
| /99 | 536870912 addresses |
| /100 | 268435456 addresses |
| /101 | 134217728 addresses |
| /102 | 67108864 addresses |
| /103 | 33554432 addresses |
| /104 | 16777216 addresses |
| /105 | 8388608 addresses |
| /106 | 4194304 addresses |
| /107 | 2097152 addresses |
| /108 | 1048576 addresses |
| /109 | 524288 addresses |
| /110 | 262144 addresses |
| /111 | 131072 addresses |
| /112 | 65536 addresses |
| /113 | 32768 addresses |
| /114 | 16384 addresses |
| /115 | 8192 addresses |
| /116 | 4096 addresses |
| /117 | 2048 addresses |
| /118 | 1024 addresses |
| /119 | 512 addresses |
| /120 | 256 addresses |
| /121 | 128 addresses |
| /122 | 64 addresses |
| /123 | 32 addresses |
| /124 | 16 addresses |
| /125 | 8 addresses |
| /126 | 4 addresses |
| /127 | 2 addresses |
| /128 | 1 address |
Determine the necessary network mask for the network size in CIDR notation
750 Hosts
11111111 11111111 11111100 00000000
2^8 = 256 2^8 = 256 128 + 64 +32 +16 + 8 + 4 + 2 + 1
fits in 10 Bits = 2^10 1024 (zeros) = 32-10 = /22 (22 ones)
Binary to Decimal
255 . 255 . 252 . 0
100 fits in 2^7 = 128 32-7= /25
14000 fits in 2^14 = 16384 32-14= /18
3789 fits in 2^12 = 4096 32-12=/20