// free-toolCSV → XLSX
Paste CSV or drop a .csv file and download a real .xlsx workbook — no more Excel import wizards mangling your encodings and delimiters. The workbook is generated locally in your browser.
no signup · no watermark · unlimited use
No. This tool runs entirely in your browser using local processing — your files never leave your device, which also makes conversion instant with no upload wait.
XLSX preserves column types, supports multiple sheets and avoids Excel's CSV-import quirks with encodings and delimiters — useful when sharing data with spreadsheet users.
Parse CSV (with headers) into clean JSON arrays.
Flatten a JSON array of objects into spreadsheet-ready CSV.
Convert JSON into clean, readable YAML for configs.
Parse YAML (with anchors and multi-docs) into formatted JSON.
Serialize JSON objects into well-formed, indented XML.
Parse XML into JSON, preserving attributes and structure.
I build fast, privacy-first web applications with Next.js — these converters run entirely in the browser, and yours can too.