BetaCalendars SheetForge is an MIT-licensed Python toolkit for generating and validating deterministic printable Gregorian calendars. Build month grids and page layouts in SVG, HTML, JSON, or CSV. Configure week starts, natural or six-week grids, adjacent-day policies, and paper sizes; validate date and year-boundary behavior. Source code and release downloads are available in the Files area. Printable calendar references: https://www.betacalendars.com/