// free-toolCSV → XLSX
CSV to 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
Frequently asked questions
Are my files uploaded to a server?
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.
Why convert CSV to XLSX at all?
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.
More data tools
CSV to JSON
Parse CSV (with headers) into clean JSON arrays.
JSON to CSV
Flatten a JSON array of objects into spreadsheet-ready CSV.
JSON to YAML
Convert JSON into clean, readable YAML for configs.
YAML to JSON
Parse YAML (with anchors and multi-docs) into formatted JSON.
JSON to XML
Serialize JSON objects into well-formed, indented XML.
XML to JSON
Parse XML into JSON, preserving attributes and structure.
Need custom tools like this in your product?
I build fast, privacy-first web applications with Next.js — these converters run entirely in the browser, and yours can too.