How to convert CSV to Excel
- Drop your CSV file on the box or choose it from your device.
- Check the preview. If the columns look wrong, change the delimiter or the encoding.
- Click Download XLSX. The whole file is converted, even if the preview only shows the first rows.
What gets detected automatically
- Delimiter: comma, semicolon, tab or pipe, based on the first lines of the file.
- Encoding: UTF-8 (with or without BOM), UTF-16, or Windows-1252, which Excel uses when it saves CSV files on Windows.
- Quoted values, including commas, quotes and line breaks inside a cell.
- Rows with a different number of columns are kept as they are; missing cells stay empty.
Numbers, dates and codes
Plain numbers such as 42, -3.5 or 1,25 (with a comma decimal separator) become real numbers you can add up in Excel. Values that only look like numbers keep their exact text: codes with leading zeros like 00123, IDs longer than 15 digits, which Excel would round, and dates, which stay as written so they can’t be reinterpreted in another day/month order.
The first row can be used as column headers: it’s shown in bold and stays visible while you scroll.
Your data never leaves your device
The file is read and converted by your browser. It isn’t uploaded to our servers and nothing is stored, which matters when a spreadsheet contains customer or financial data.
Frequently asked questions
Why does Excel put all my CSV data in one column?
Excel expects the delimiter of your system’s regional settings, so a comma-separated file can end up in a single column when the system expects semicolons, or the other way round. Converting to XLSX avoids the problem because the columns are already split.
Accents look broken. What can I do?
The file is probably in a different encoding from the one detected. Choose Windows-1252 or UTF-8 in the Encoding menu and check the preview until the text looks right.
How large a file can I convert?
There’s no limit of ours. Files with hundreds of thousands of rows convert in a few seconds on a computer. Excel itself allows up to 1,048,576 rows and 16,384 columns per sheet.
Are formulas or formatting kept?
CSV files only contain plain values, so there are no formulas or formats to keep. The XLSX file has your data, a bold header row and column widths adjusted to the content.