Size | Comment |
---|---|
/29 | starter pack |
/28 | usually enough |
/27 | default allocation |
/26 | usually enough |
/25 | still a lot of IPs! |
/24 | are you an organization? |
The current guideline is to allocate a /27 or smaller by default, keeping space for up to a /26 if possible. Don't allocate more than a /25 worth of addresses and please think before you allocate: If you are going to have 2-3 servers and two VPN-spaces, a /28 is enough to suit your needs. Same will go for most home-networks. This is not public internet, but our IPv4-space is valuable too! If you need a /24 or larger, please ask in the IRC chan or on the mailing list.
For example, if there is no /27 free, you can split up a /26 into two /27. If you are looking for a /27 but there are none showing in the Open Netblocks tool, instead pick one of the /26 and click Take it! When registering your inetnum, instead of writing 172.2x.xxx.0-172.2x.xxx.63 then you can write 172.2x.xxx.0-172.2x.xxx.31. This will get you a /27 and save our IP space for others.
To register for example 172.20.150.0/27, you need to fill in 172.20.150.0-172.20.150.31.
{ "prefixes": { "29": [ "172.20.128.48_29", "172.20.15.240_29", "172.21.69.160_29", "172.21.90.0_29", "172.21.90.8_29", "172.21.94.192_29", "172.22.128.64_29", "172.22.148.240_29", "172.22.98.0_29", "172.23.105.160_29", "172.23.105.168_29", "172.23.124.128_29", "172.23.183.224_29", "172.23.188.0_29", "172.23.35.128_29" ], "28": [ "172.20.146.0_28", "172.20.146.16_28", "172.20.159.160_28", "172.20.159.176_28", "172.20.228.128_28", "172.20.39.128_28", "172.21.66.32_28", "172.21.66.48_28", "172.21.67.128_28", "172.21.93.96_28", "172.22.105.0_28", "172.22.186.112_28", "172.22.188.192_28", "172.23.128.0_28", "172.23.183.16_28" ], "27": [ "172.20.132.96_27", "172.20.139.128_27", "172.20.150.160_27", "172.20.159.128_27", "172.20.163.64_27", "172.20.177.128_27", "172.20.224.96_27", "172.20.231.224_27", "172.20.28.128_27", "172.20.46.192_27", "172.20.5.224_27", "172.22.101.0_27", "172.22.137.96_27", "172.22.180.0_27", "172.22.180.32_27" ], "26": [ "172.20.138.192_26", "172.20.15.128_26", "172.20.160.64_26", "172.20.224.128_26", "172.22.127.128_26", "172.22.127.192_26", "172.22.128.0_26", "172.22.179.192_26", "172.23.107.128_26", "172.23.107.192_26", "172.23.193.192_26", "172.23.232.128_26", "172.23.35.0_26", "172.23.35.64_26", "172.23.45.128_26" ], "25": [ "172.20.139.0_25", "172.20.161.0_25", "172.20.232.0_25", "172.22.107.128_25", "172.22.116.128_25", "172.22.160.128_25", "172.23.100.0_25", "172.23.116.128_25", "172.23.196.128_25", "172.23.203.0_25", "172.23.226.128_25", "172.23.238.128_25", "172.23.67.128_25", "172.23.71.128_25", "172.23.85.128_25" ], "24": [ "172.20.226.0_24", "172.20.35.0_24", "172.22.104.0_24", "172.22.139.0_24", "172.22.140.0_24", "172.22.173.0_24", "172.22.176.0_24", "172.23.117.0_24", "172.23.166.0_24", "172.23.176.0_24", "172.23.204.0_24", "172.23.216.0_24", "172.23.239.0_24", "172.23.41.0_24", "172.23.68.0_24" ], "23": [ "172.20.144.0_23", "172.20.22.0_23", "172.20.60.0_23", "172.21.124.0_23", "172.22.174.0_23", "172.22.190.0_23", "172.23.138.0_23", "172.23.154.0_23", "172.23.164.0_23", "172.23.184.0_23", "172.23.210.0_23", "172.23.228.0_23", "172.23.46.0_23", "172.23.80.0_23" ] }, "mtime": "2025-02-07T21:09:33Z" }