CIDR Workbench is a focused subnet tool for network operators, students and engineers who need the calculation and the reasoning beside it. It handles IPv4 and IPv6 CIDR boundaries with family-appropriate semantics. Both planners visualise repeated subnet splits as a vertical hierarchy, let users inspect and rejoin valid siblings, and copy complete plans as Markdown or JSON. IPv6 output uses exact 128-bit boundaries without presenting a broadcast address or IPv4-style usable-host count. It does not send entered addresses or results to a server.
Editorial standard
Every indexable tool must provide working utility, instructions, interpretation, a reviewed method, edge cases and source links. Planned features stay labelled as planned rather than being published as thin pages.
Contact
Questions and corrections can be sent to info@iomdev.com.