ConvertSheet

ConvertSheet is a high-performance, privacy-first web utility for developers, data engineers, and spreadsheet users. It transforms nested JSON, large CSVs, Parquet, and Excel spreadsheets directly inside browser memory via WebAssembly and DuckDB-WASM — 100% client-side with zero cloud uploads and zero tracking. In addition to file conversions, ConvertSheet features developer utilities (JWT decoder, epoch converter, base64 encoder) and privacy-first financial calculators for Indian borrowers and global investors.