About xlsxtocsv.com
A free tool that does one job well: turning spreadsheets into clean CSV files (and CSV files back into Excel), without sending them anywhere.
Why it exists
CSV is how data moves between programs. Email platforms, CRMs, online stores, accounting tools and databases all want CSV, while most people keep their data in Excel. Excel can save a CSV, but only one sheet at a time, and the result often opens with garbled accents or missing zeros.
Most online converters ask you to upload the file to their server. That's a poor fit for customer lists, payroll exports or anything else private. This converter runs entirely in your browser instead. The page loads once, and after that your files are read, converted and saved on your own computer.
How accurate is it?
The converter reads the number formats stored in your workbook and applies them the way Excel does, so currency, percentages, dates, times, phone-number patterns and leading zeros come out as they look on screen.
We test it against more than 1,100 real spreadsheets from public test collections, including files from many versions of Excel since Excel 97, LibreOffice and other programs, plus deliberately damaged files. LibreOffice serves as an independent reference. Where results differ, it's almost always because LibreOffice recalculates formulas or uses its own regional settings, while we keep the values Excel saved.
What it can't do
- Open a password-protected file without its password. It can unlock files when you type the password, but it can't guess one.
- Open very old Excel 4 (and earlier) files, or LibreOffice files protected with the old Blowfish encryption. Save those again in a current program first.
- Recalculate formulas. A CSV holds values, so we write the result Excel last saved for each formula.
- Keep formatting like colors, bold text, column widths or charts. CSV is plain text, so no tool can keep those.
Sister sites
ListaFix has free browser tools for cleaning email lists: removing duplicates, fixing typos and splitting big lists. Veml checks whether the email addresses on a list are real before you send to them.