Excel to CSV Converter

How to convert Excel to CSV

1. Drop a workbook on the drop zone or click it to choose one: .xlsx, .xlsm, .xlsb, old .xls files and LibreOffice .ods are accepted.
2. In the Excel → CSV panel, pick the Sheet to convert. The preview shows the first lines of the CSV exactly as they will be written.
3. Choose the Delimiter, the Encoding and the Line endings, then click Download CSV. To convert every sheet at once, click Download all sheets (ZIP): you get one .csv file per sheet, named after the sheet.

How to convert CSV to Excel

1. Drop one or more .csv, .tsv or .txt files, or paste CSV data in Or paste CSV data.
2. Leave Delimiter and Decimal separator on Auto-detect, or set them if the preview looks wrong. Choose how Dates are written in your file.
3. Check the table under How the cells will be stored: numbers and dates are right-aligned, text is left-aligned.
4. Click Download Excel file (.xlsx). Several CSV files give one workbook with one sheet per file.

Everything happens in your browser tab: the files are never uploaded.

Choosing the right CSV options

Values. As displayed in the spreadsheet writes the values with the number format saved in the file: 1,235 for a number formatted without decimals, a date in the date format of the cell. Formatted numbers always use a dot for decimals and a comma for thousands. Raw values (full precision, ISO dates) writes the stored value instead: 1234.5, 2026-09-30, 2026-09-30 14:05:00. Raw values are safer for databases and scripts; displayed values are better when a person will read the file. Formulas are exported as the result saved in the file, never as formulas.

Delimiter. Most software expects a comma. Excel set to French, German or another language that writes decimals with a comma expects a semicolon, and the semicolon avoids quoting every decimal number. Cells that contain the delimiter, quotes or line breaks are quoted following RFC 4180.

Encoding and BOM. UTF-8 keeps every character. Excel on Windows only recognises UTF-8 when the file starts with a byte order mark, so tick Add a byte order mark (BOM) if accents show up as é there. Windows-1252 suits old Western European software; characters it can’t represent are written as ? and the note above the preview counts them. UTF-16 LE is what Excel’s “Unicode text” export uses.

Protect against formula injection puts an apostrophe before cells starting with =, +, - or @, so a spreadsheet opening the CSV won’t run them. Plain numbers such as -12 are not changed.

How CSV data becomes Excel cells

Numbers such as 1234.56, 1,234.56, 1 234,56 or 12.5% become real numbers (percentages keep a percent format). Keep leading zeros (007, ZIP codes) as text stops 007 or 01234 from losing their zeros, and integers longer than 15 digits always stay text because Excel can only store 15 significant digits. Dates in ISO format are always recognised; 30/09/2026 needs Day/month/year. Tick Keep everything as text (no number or date conversion) to store every value exactly as written. With First row contains column names, the header row is frozen and gets filter buttons, and column widths are set from the content.