I second Netbox, which has detailed IPv4/6 IPAM plus many other features: <https://demo.netbox.dev/static/docs/core-functionality/ipam/> IP Address Management - NetBox Documentation<https://demo.netbox.dev/static/docs/core-functionality/ipam/> demo.netbox.dev<https://demo.netbox.dev/static/docs/core-functionality/ipam/> [favicon.png]<https://demo.netbox.dev/static/docs/core-functionality/ipam/> -mel On Nov 16, 2023, at 10:31 AM, Jesse DuPont <jesse.dupont@celeritycorp.net> wrote: phpIPAM for the win. NIPAP is effective, if basic. I've heard of lots of people who like Netbox. On 11/16/23 11:12 AM, Niels Bakker wrote: * aaron1@gvtc.com<mailto:aaron1@gvtc.com> (Aaron Gould) [Thu 16 Nov 2023, 19:04 CET]: For years I've used an MS Excel spreadsheet to manage my IPv4 addresses. IPv6 is going to be maddening to manage in a spreadsheet. What does everyone use for their IPv6 address prefix management and documentation? Are there open source tools/apps for this? The first three hits for "open source ipam" on a search engine are: - phpipam.net/ - spritelink.github.io/NIPAP/ - github.com/netbox-community/netbox I'd pick the last option, or possibly Nautobot. You may want to scroll through https://github.com/topics/ipam for more options. -- Niels.