KiwiGrapher is a lightweight web app: it runs entirely in your browser, so there are no servers crunching data and no per-user infrastructure to pay for. That keeps running costs low enough to offer it free to New Zealand classrooms.
It's built and maintained as a contribution to NZ statistics education. If that ever changes, the core graphing tools students rely on for NCEA will stay free.
Placeholder: if you add a funding model later, for example optional donations, grants or sponsorship, describe it here so the "how is it free" question has an honest, specific answer.