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XLS to XLSX Converter

Turn old .xls workbooks into modern .xlsx files that look the same, a whole stack at a time, including '.xls' exports that Excel warns about.

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or drop files here

Accepts XLS

Encrypted upload. Files are deleted automatically after 1 hour.

About XLS to XLSX

XLS to XLSX is for the spreadsheets that still come out of older accounting packages, government portals and archive folders in the Excel 97–2003 format. Newer apps, Python libraries and many upload forms expect .xlsx instead, and the old format stops at 65,536 rows. Add one .xls or a whole stack of them, and each comes back as an .xlsx with the same sheets in the same order, under the same names, with all of them also in one ZIP. Many banks, payment platforms, ERP and government systems export a web page table under an .xls name, which Excel opens only after warning that the file format and extension don't match. Those files, Excel 2003 XML files and .xlsx files that were simply renamed are recognized and converted as well, and the result says what each one really was.

The look comes across with the data: fonts with their size, bold, italic, underline and colour, cell colours, borders, alignment and wrapped text, number formats for dates, currency, percentages and thousands separators, merged cells, column widths and row heights, hidden rows, columns and sheets, frozen header rows, links and cell comments. Dates stay real dates. Two things don't come across: formulas are saved as the results they showed, and charts and pictures are not carried over. If you need live formulas, open the .xls in Excel and use Save As to pick .xlsx. If a script only needs the rows, Excel to CSV reads .xls files too and gives one CSV per sheet.

How to use XLS to XLSX

  1. 1
    Upload the .xls files

    Choose or drop one or more workbooks saved in the Excel 97–2003 format, or '.xls' exports from online systems. Up to 20 files go in one task, 50 with VIP.

  2. 2
    Click XLS to XLSX

    Each file is checked for what it really is, then rebuilt as a new workbook in an isolated process on our server.

  3. 3
    Download the .xlsx files

    Every file keeps its name, so sales-2009.xls becomes sales-2009.xlsx, and several arrive in one ZIP as well.

Why use Cubfile for this

  • The formatting comes along

    Fonts, colours, borders, merged cells, number formats, column widths and frozen rows look as they did in the .xls.

  • A whole stack at once

    Convert a folder of old workbooks in one task and download them one by one or together as a ZIP.

  • Web-page .xls exports fixed

    Bank, ERP and portal exports that are really web pages, Excel 2003 XML or renamed .xlsx files become real workbooks.

  • All sheets, dates intact

    Every sheet keeps its name and place in the tab order, dates stay real dates, and a sheet can now grow past 65,536 rows.

FAQ

XLS to XLSX: questions and answers

Will XLS to XLSX keep my formulas and formatting?
The formatting, yes. Fonts, colours, borders, alignment, merged cells, number formats, column widths, hidden rows and frozen panes come across. Formulas are saved as the results they showed, not as formulas, and charts and pictures are left out. If you need live formulas or charts, open the .xls in Excel and use Save As to pick .xlsx.
Excel says the file format and extension don't match. Can XLS to XLSX fix it?
Usually, yes. That warning often comes up with '.xls' files exported by banks, payment platforms, ERP or government systems that are really a web page table, an Excel 2003 XML file or a new .xlsx under an old name. XLS to XLSX recognizes what the file really is, turns its tables into real Excel sheets and tells you what it found. Other tools on this site point such files here.
How do I convert several .xls files?
Add them all to the same task. Each comes back as an .xlsx under its own name, and you can download them one by one or all together in one ZIP. If the other software wants CSV, JSON or SQL instead, look in Spreadsheet & Data Converter.
Is XLS to XLSX free, and how many files can I convert at once?
Yes. Without signing up you have 2 tasks and with a free account 2 a day, each converting up to 20 files of 50 MB, while VIP converts 50 files of up to 1 GB per task with no daily limit.
What happens to my workbooks after the conversion?
They're deleted automatically, together with the .xlsx files, one hour after processing. Uploads are encrypted and each job runs on its own, isolated from other people's files.
Share XLS to XLSX with a friendIt runs in any browser, and they can try it without signing up.

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