Guides to working with CSV files

Comparisons and practical tutorials: how to open, convert, edit and query CSV files with free tools and without uploading your data.

• Best free online CSV to JSON converters in 2026 (tested) — We compared six free CSV to JSON converters: CSV Creator, CSVJSON, ConvertCSV, TableConvert, Online CSV Tools and Mr. Data Converter. Privacy, quoting, nested output, limits.
• How to open a CSV in Excel without breaking it (one column, lost zeros, wrong accents) — Why Excel shows a CSV in a single column, deletes leading zeros, turns codes into dates and garbles accents, and the four ways to open it correctly, including the import wizard and converting to XLSX.
• Convert CSV to Excel: 5 ways, from double-click to Python — Five ways to convert a CSV file to Excel: Excel's import wizard, Google Sheets, LibreOffice, Python with pandas, and an online converter. When each one fits, and how to keep leading zeros and accents.
• Best free online CSV editors (and when to use a desktop app instead) — Compared: CSV Creator, TableConvert, Edit CSV Online, Google Sheets and the VS Code Edit csv extension, plus desktop options Modern CSV and Tad. Which editor keeps your data intact and private.
• How to create a CSV file: online, in Excel, Google Sheets, Notepad and Python — Five ways to make a CSV file step by step: an online CSV maker, Excel, Google Sheets, Notepad or TextEdit, and Python, plus the mistakes that break imports (separators, encoding, leading zeros).
• How to query a CSV file with SQL without a database (5 tools compared) — Five ways to run SELECT, WHERE and GROUP BY on a CSV without importing it into a database: in the browser with CSV Creator, DuckDB CLI, q, csvkit's csvsql and SQLite. Commands and limits.