CSV to Excel
Turn CSV or pasted rows into a real .xlsx workbook.
CSV to Excel builds a genuine .xlsx workbook from CSV files or pasted rows. The separator is detected and shown for you to confirm, numbers and dates are recognised so they land as real Excel values rather than text, and several files become several sheets. The workbook is written in your browser.
Loading CSV to Excel…
Runs entirely on your device. No file or text you enter here is uploaded. How to verify it.
How to use CSV to Excel
- Add one or more CSV files, or paste rows straight in.
- Confirm the separator and whether the first row is a header.
- Download the .xlsx workbook.
Questions about CSV to Excel
Why not open the CSV in Excel directly?
You can, but Excel guesses. It turns 007 into 7, reads 03/04 as a date in whatever order the machine is set to, and mangles long product codes into scientific notation. Producing a real workbook lets each value be written with its type already decided, so nothing is guessed on opening.
Are leading zeros preserved?
Yes. A value like 007 or a postcode that starts with a zero is written as text, not as a number, so the zeros survive. That is the single most common complaint about opening a CSV in Excel and it is the reason this tool exists.
Can I put several CSV files into one workbook?
Yes. Each file becomes its own sheet, named after the file. Sheet names are trimmed to the 31 characters Excel allows, forbidden characters are removed, and duplicates get a numbered suffix, because two sheets with the same name produce a file Excel refuses to open.
Will Excel show a repair prompt when it opens the file?
It should not. The most common cause of that prompt is a control character that XML cannot represent surviving into the file; those are stripped on the way out. The workbook is written as a proper OOXML package with all the parts and relationships Excel expects.
Does it write formulas or formatting?
No. It writes values, with dates styled so they display as dates. Column widths, colours, formulas and conditional formatting are not written, because a CSV never contained them in the first place.
Is CSV to Excel really free, with no limits?
Yes. There is no account, no daily cap, no file-size tier and no watermark, because there is no server cost to recover. The site is funded by clearly disclosed partner recommendations on the Partners page, never by metering the tools.
Are my files or text uploaded when I use CSV to Excel?
No. Everything is processed by JavaScript running in your browser, on your device. You can verify it: open your browser's developer tools, switch to the Network tab, and use the tool. You will see no request carrying your data — because there is nowhere for it to go.