Celtrim

Convert XLSX to CSV

Open an Excel workbook, pick a sheet or take all of them, and download clean CSV with the quoting and encoding done properly. Nothing leaves your browser.

Drop an Excel workbook here

.xlsx, .xlsm, or .xltx

Free · no sign-up · processed on your device

How it works

  1. 01

    Drop the workbook

    An .xlsx, .xlsm, or .xltx file is read in your browser. Every sheet it contains is listed with its row count.

  2. 02

    Pick the sheet and the separator

    CSV holds one table, so choose which sheet you need — or take all of them at once. Comma, semicolon, and tab are all available.

  3. 03

    Download

    One sheet downloads as a .csv. A whole workbook downloads as a .zip with one correctly named CSV per sheet.

Excel can already save a CSV, so the reason to use a converter is everything Excel does around that. It exports the active sheet only, uses your locale's separator and date format without telling you, and writes a file whose encoding Excel itself then struggles to read back. Converting here makes each of those an explicit choice, handles a whole multi-sheet workbook in one go, and never asks you to install anything or hand a file to a server.

What survives the conversion

CSV is a much smaller format than xlsx, so a conversion is really a set of decisions about what to keep. Here is every one of them.

Formulas becomes The value they last calculated to
CSV has no concept of a formula. Excel stores the last computed result alongside each formula, and that is what gets written, so a SUM becomes its total rather than the text =SUM(B2:B9).
Dates becomes ISO dates, as 2026-03-04
Excel stores a date as a number of days, and the display format is a local preference. Writing ISO means the date reads the same in every country and imports cleanly everywhere.
Multiple sheets becomes One CSV per sheet
A CSV file is a single table by definition. Rather than silently exporting only the first sheet, the way many converters do, each sheet becomes its own file inside a zip.
Formatting, charts, macros becomes Nothing — and that is correct
Colours, merged cells, images, pivot caches, and VBA have no CSV representation. If you need to keep those, CSV is the wrong target format entirely.

Before you convert

  • Check which sheet actually holds the data. Workbooks often keep notes or lookup tables on other tabs that you do not want in the export.
  • If the file is going into a European system, switch the separator to semicolon before downloading rather than fixing it afterwards.
  • Empty rows left behind by deleted content are skipped by default, so the CSV starts and ends where the data does.
  • Want to see the file before converting it? Open it in the reader first.

Common questions

How do I convert an XLSX file to CSV?
Drop the workbook into the converter above, choose the sheet you want, and download it. If the workbook has several sheets you can export all of them at once as a zip containing one CSV per sheet.
Can it convert every sheet at once?
Yes. When the workbook has more than one sheet, an extra button appears that packages every sheet into a single .zip download, each file named after the workbook and the sheet it came from.
Why does Excel open my CSV with everything in one column?
Excel expects the separator its locale uses, which is a semicolon in much of Europe. Set the separator to Semicolon before downloading and leave Excel-friendly encoding on, which adds the byte order mark Excel looks for to recognise UTF-8.
What happens to my formulas?
They are exported as the values they last calculated to. That is the only thing a CSV can carry, and it matches what the sheet was showing when it was last saved in Excel.
Will my accented characters and emoji survive?
Yes. The CSV is written as UTF-8, and Excel-friendly encoding prefixes it with a byte order mark so Excel opens it as UTF-8 rather than guessing at an ancient code page.
Does it work with .xls files from older Excel?
No. The legacy .xls format is a completely different binary container. Open the file in Excel and use File then Save As to store it as .xlsx first, then convert it here.
What about a password-protected workbook?
A workbook that asks for a password before it opens is encrypted and cannot be read until it is decrypted. Run it through the read-only Excel converter first, then bring the unlocked copy back here.
Is my workbook uploaded anywhere?
No. The file is read and the CSV is written entirely in your browser using local JavaScript. Nothing is transmitted, stored, or logged, which also means the tool works offline once the page has loaded.