Spreadsheets deserve an engine that anyone can embed, audit, and run on their own server. IronCalc is an open-source spreadsheet engine with a browser editor that reads and writes real Excel files: open an xlsx, edit values and formulas in the grid, format cells, and save the workbook back without a round trip through a proprietary suite. The grid feels familiar on purpose, with a formatting toolbar for fonts, fills, borders, number formats, and alignment, sheet tabs along the bottom, and templates for invoices, expense trackers, calendars, timesheets, and project plans so a new workbook starts from structure instead of a blank page. Files import from xlsx and export again to the same format, which keeps IronCalc honest as a working tool instead of a viewer. Underneath, the calculation engine is a library other software can call, so the same formulas that evaluate in your browser can also run inside a Python script, a Node service, or a WebAssembly build embedded in your own product. Self-hosting puts the whole webapp behind your own address: one Docker Compose brings up the spreadsheet server with its proxy, and teams share workbooks from infrastructure they control rather than uploading budgets to a stranger's cloud. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT and Apache-2.0 dual licensed.

With over 11,200 GitHub stars and adoption by France's sovereign digital workspace LaSuite serving 20,000+ government users, Grist is the relational spreadsheet that ends the false choice between fragile Excel files and expensive custom database development — storing all data in portable SQLite files while providing true relational structure where VLOOKUPs become actual linked records that update instantly across entire documents. Python-powered formulas replace complex Excel syntax with clear, readable logic using the full Python standard library, while familiar Excel functions remain available for users who prefer them. Granular access rules control permissions at row, column, table, and cell levels — not just entire sheets — enabling multi-department documents where each team sees only their authorized data. The flexible layout system combines spreadsheets, card views, charts, calendars, and custom widgets on configurable dashboard pages that transform raw data into operational interfaces. Real-time collaboration lets multiple users edit simultaneously with automatic snapshot history capturing every change for full audit trails and point-in-time recovery. AI formula assistance connects to OpenAI, Llama, or any OpenAI-compatible endpoint via OpenRouter to generate formulas from natural language descriptions. The REST API and webhooks enable integration with n8n, Zapier, and custom automation, while incremental imports keep external data sources synchronized. Deployable via Docker with OIDC, SAML, and SCIM authentication support. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.