Convert XLS to XLSX Online

Turn your old Excel 97-2003 files (.xls) into the modern .xlsx format, keeping formulas, formatting, data validation and print settings. Nothing is uploaded to any server.

    Your files are converted in your browser and are never uploaded to this website.

    What is kept in the conversion?

    Kept

    • All sheets, including hidden ones, with their names and tab colors
    • Values, dates and formulas (they are recalculated when the file is opened)
    • Fonts, colors, fills, borders, alignment and number formats
    • Text with mixed formatting inside a cell
    • Merged cells, column widths, row heights, hidden and grouped rows and columns
    • Frozen panes, zoom and gridlines
    • Comments, hyperlinks, drop-down lists and data validation
    • Named ranges, print area, print titles, page setup, headers and footers
    • Filters and sheet protection

    Not included

    • Images, charts, shapes and form buttons
    • Conditional formatting
    • VBA macros (an .xlsx file cannot contain macros)
    • Password-protected workbooks (remove the password first)

    If a file has any of these, you will see a notice next to it.

    What does converting XLS to XLSX mean?

    XLS is the binary format Excel used up to version 2003. XLSX is the current format, based on compressed XML, used by Excel, Google Sheets and LibreOffice since 2007.

    Converting an .xls file to .xlsx makes it smaller, lets it hold more than a million rows and makes it work without "compatibility mode" warnings in any modern program.

    Advantages

    • Keeps every sheet, value, date and formula.
    • Keeps fonts, colors, borders, number formats and merged cells.
    • Includes comments, hyperlinks, data validation and print settings.
    • Several files at once, downloaded one by one or in a ZIP.
    • Private: the conversion happens in your browser.

    How to convert XLS to XLSX

    1. Drag one or more .xls files onto the tool, or click to choose them.
    2. Wait for each file to be converted; you will see the progress and the size before and after.
    3. Check any notices about items that could not be included.
    4. Download each .xlsx file or all of them together in a ZIP.

    Ideas for using it

    • Update old accounting or inventory files.
    • Open .xls files in Google Sheets or other apps that prefer .xlsx.
    • Get past the 65,536-row limit of the old format.
    • Reduce file size to send them by email.
    • Migrate historical files to a current format.

    Tips for the best result

    • If the file has an opening password, remove it in Excel first.
    • Charts and images are not converted: check the notice next to the file.
    • VBA macros cannot be stored in .xlsx; save it as .xlsm in Excel if you need them.
    • Convert several files together and download them in a ZIP.

    Frequently asked questions

    Is it free to convert XLS to XLSX?

    Yes, with no sign-up and no file limit.

    Are my files uploaded?

    No. They are read and converted inside your browser; they are never sent to the server.

    Are formulas kept?

    Yes, including shared and array formulas, references to other sheets and named ranges. The workbook is recalculated when it is opened.

    What is not converted?

    Images, charts, shapes, conditional formatting and VBA macros. If the file has them, you will see a clear notice.

    Does it work on mobile?

    Yes, it works on phones and tablets.

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