CSV to Excel Converter

How to convert CSV to Excel

1. Open a .csv file or paste CSV text, then press Convert.
2. Confirm the separator and whether the first row holds column names.
3. Download the .xlsx workbook and open it in Excel, Google Sheets, Numbers or LibreOffice.

The problem with double-clicking a CSV

When Excel opens a CSV directly, it guesses what every value means, and the guesses are often wrong. Leading zeros vanish, so the ZIP code 02134 becomes 2134 and an employee number 000781 becomes 781. Long numbers such as 16-digit card references or 18-digit tracking IDs get rounded, because Excel stores numbers with 15 significant digits and replaces the rest with zeros. Text like 3-4 or MARCH1 can turn into dates. Once the file is saved again, the original values are gone.

Converting to .xlsx first avoids that. This tool decides the type of each cell under strict rules and writes it into the workbook explicitly, so Excel has nothing left to guess.

How cell types are decided

Dates are deliberately left as text. Deciding whether 04/05/2026 means April or May depends on where the file came from, and a wrong guess is worse than none. If you want them as real dates, select the column in Excel and use Text to Columns or a DATEVALUE formula, where you control the format. Prefer every value as text? Turn off Turn numbers and true/false into real values.

What the workbook looks like

• One sheet, named after your file, with the first CSV row at the top as the header row.
• Column widths set from the content, so you don't open a grid of cut-off cells.
• Commas, quotes and line breaks inside quoted CSV fields stay inside their cell.
• UTF-8 text including accents, Cyrillic, Chinese and emoji is stored as Unicode, which avoids the garbled characters you sometimes get when Excel imports a CSV with the wrong encoding.

A sheet can hold up to 1,048,576 rows and 16,384 columns, and one cell up to 32,767 characters. The tool warns you if your data runs past those limits rather than producing a file Excel refuses to open.

Separator and encoding detection

CSV files aren't always comma-separated. Exports from European systems often use semicolons, database dumps may use tabs or pipes. The separator is detected from the first rows, and the preview shows the result before you download, so you can spot a wrong split immediately and correct it from the menu. Files that aren't valid UTF-8 are read as Windows-1252, the encoding older Windows programs typically used.

All of this runs in your browser; the CSV is never uploaded. To go back from a workbook to plain text, use Excel to CSV.

More ways to use this tool