gridcraft is an open-source spreadsheet application developed by ArtCraft, a software studio focused on open-source tools. Its primary function is to provide a familiar spreadsheet environment that supports cells, formulas, and XLSX files, with a calculation engine written in Rust and capable of running on desktop computers and in web browsers through WebAssembly. The application is designed to work with standard spreadsheet workflows, including editing cells, applying number formats, organizing tables, and building charts. XLSX is the native file format, allowing users to open, edit, and save workbooks while preserving original structure where possible. The application includes more than 500 worksheet functions, covering dynamic array features, LET, and LAMBDA. Its interface resembles a traditional spreadsheet layout with an Excel-style ribbon, worksheet tabs, and a formula bar. GridCraft is still in an alpha stage, meaning complex files with specialist Excel functions, external data, or macros may not behave identically. The project is open-source, and the software can be downloaded as a desktop package (for example, a .dmg file for macOS) or used directly in a browser. The independent site gridcraft.me provides the official browser build, installation guides, and practical tutorials, while the software itself is maintained by ArtCraft. Typical use cases include experimenting with household budgets, class gradebooks, or sales summaries to evaluate the workflow. Users are encouraged to start with a small Excel workbook, open it in the GridCraft online editor, inspect sheet names, column widths, number formats, and formulas, then make changes and save a copy to verify results. The application supports common operations such as SUM and IF functions, and users can build confidence by entering values, applying formulas, and observing updates when source cells change. For data analysis, users can create charts for quick comparisons or use PivotTables to group repeated categories, with sample workbooks available to illustrate how tables and charts share source data. Technical details include that the calculation engine runs locally, keeping interaction close to the user’s data. The software is written in Rust and compiled to WebAssembly for browser use. The upstream project documents a broad set of functions, but users are advised to verify their own results, especially when working with business-critical models. The site also offers comparisons with Microsoft Excel and hands-on usage experiences, serving as a separate resource from the official ArtCraft project.