XLS to XLSX Converter
Bring Excel 97-2003 workbooks up to the current .xlsx format, with every sheet, formula and cell format carried over, so they open without Compatibility Mode and can grow past the old row limit.
Document Converter
or drag PDF, DOC, DOCX … files here ·
Up to 95 MB each· 20 files at once· Removed after 30 min
Your files are removed from our servers 30 minutes after processing.
150 DPI turns an A4 page into about 1240 × 1754 px. Use 300 for printing.
Convert the whole file or only some pages or slides (PDF and presentation input).
Pages or slides to convert, e.g. 1-3, 5, 8-10.
UTF-8 works for every language. Choose UTF-8 with BOM if Excel or Notepad on Windows shows garbled characters; legacy encodings only for old software.
LF for macOS, Linux and code editors; CRLF for older Windows programs such as classic Notepad.
Comma is standard. Use semicolon for Excel in countries that write decimals with a comma (Germany, France, Brazil).
Excel input with several sheets: convert all of them (one section or file per sheet) or only the first.
Files are deleted 30 minutes after processingPrivacy policy
1,048,576
Rows per worksheet in an .xlsx file, against 65,536 in the old .xls format.
Figures from Microsoft's Excel specifications and limits and its notes on earlier Excel versions.
Why old .xls files are worth upgrading
The .xls format belongs to Excel 97 through Excel 2003. Microsoft's file format list describes it as the binary BIFF8 format. Excel 2007 replaced it with .xlsx, and every version since has opened old workbooks in Compatibility Mode, which keeps the old limits in place and switches off newer features until the file is saved in the current format.
Those limits bite in everyday work. A sheet stops at row 65,536 and column IV, so a year of transaction exports or sensor readings simply does not fit. Some newer functions, conditional formats and larger styles are not available, and every save triggers a compatibility check. Shared drives full of old .xls files are also harder to search and preview in modern tools, which read .xlsx natively.
Converting rewrites the workbook in the format current software expects, while keeping the content you built over the years.
Binary XLS and Open XML XLSX
XLS
Excel 97-2003 workbook
The binary spreadsheet format Excel used before XLSX became the default. It stores sheets, formulas and charts in an older closed structure with tighter size limits. Current spreadsheet apps still open it, and some business systems keep exporting it.
- Vendor format
XLSX
Excel workbook
Microsoft Excel's default format since 2007, built on the Office Open XML standard. A workbook can hold several sheets with formulas, charts, formatting and data validation. Excel, Google Sheets, Numbers and LibreOffice all open it, though some advanced features only work in Excel.
- Open standard
Why convertMoving from .xls to .xlsx gives up compatibility with Excel 2003 and earlier, and gains the larger grid, current features and an open, documented format. Upgrade in this direction unless someone you send files to still runs a pre-2007 version.
XLSX is part of Office Open XML, standardized as ECMA-376 and ISO/IEC 29500. Inside, a workbook is a ZIP package of XML files, one per sheet plus shared strings and styles, which is why so many programs besides Excel can read and write it reliably. Google Sheets, Apple Numbers and LibreOffice Calc all open the converted file.
Macros need a different target
VBA macros are not kept in .xlsx
Microsoft's format list says plainly that .xlsx cannot store VBA macro code or Excel 4.0 macro sheets. Before converting, check whether the workbook depends on:
- Buttons that run a macro
- Custom functions written in VBA
- Automatic imports or reports triggered on open
If any of those apply, open the .xls in Excel and use Save As → Excel Macro-Enabled Workbook (.xlsm), which keeps the code. For workbooks that are only data, formulas, formats and charts, which is most of them, the .xlsx made here is the right result.
Not sure whether a workbook has macros? In Excel, press Alt+F11 to open the code editor; an empty project means there is nothing to lose.
After the upgrade: checks worth making
Open the converted workbook and look at the title bar. The words Compatibility Mode should be gone, which tells you Excel now treats the file as a current workbook with the full grid and every feature available. From here on, saving with Ctrl+S keeps it as .xlsx.
Next, test the parts that do the work. Change an input cell and see that totals update, open each chart, and use any filters or pivot tables. If the workbook pulls data from other files, Excel may ask to update links on opening; that is normal and shows the formulas are still connected.
Finally, decide what to do with the originals. Keeping the .xls files in an archive folder costs little and gives you a fallback. Once a converted workbook has been used for a while without problems, the old copy can usually be retired.
Upgrading a folder of workbooks
Add up to 20 workbooks at a time, each up to 95 MB. Every sheet comes over with its name and order, formulas stay live, and the file name stays the same with the new extension. Uploaded files are removed after processing and the converted ones 30 minutes later.
Open a few converted files and check the sheets that matter most, especially formulas that point to other workbooks, since those links keep their old paths. If you also need the data in another shape, the Data Converter turns sheets into CSV or JSON, and the Document Converter handles the other office formats, including tables for LaTeX papers with XLSX to LaTeX.
How to convert XLS to XLSX
Add the .xls files
Drop one or more Excel 97-2003 workbooks on the box above, or press Choose Files.
Keep all sheets
XLSX with Keep all formatting and All sheets is preset, so the workbook comes over complete.
Convert and open
Press Convert and open the .xlsx in Excel, Google Sheets, Numbers or LibreOffice Calc.
XLS to XLSX questions
What is the practical difference between .xls and .xlsx?
An .xls file uses the binary BIFF8 format of Excel 97 to 2003 and holds at most 65,536 rows and 256 columns per sheet. An .xlsx file is Office Open XML and holds 1,048,576 rows and 16,384 columns. Newer Excel features only work fully in .xlsx.
Are VBA macros kept when an .xls becomes .xlsx?
No. Microsoft states that the .xlsx format cannot store VBA macro code. If the workbook relies on macros, open the .xls in Excel and save it as an .xlsm macro-enabled workbook instead.
Do formulas still calculate after the conversion?
Yes. Formulas are carried over as formulas, not as fixed values, and Excel recalculates them when the file opens. References to other workbooks keep their paths, so check those if the linked files have moved.
Will charts and cell colors survive?
With Keep all formatting, cell styles, number formats, column widths and charts are carried over as closely as the XLSX format allows. Very old chart types may look slightly different.
Can I convert dozens of old workbooks at once?
Up to 20 per batch, each up to 95 MB. Every workbook becomes its own .xlsx file with the same name.
Why does Excel still offer to save in .xls?
Excel keeps the Excel 97-2003 format for people who share files with very old versions. Unless someone you work with still uses Excel 2003, .xlsx is the better choice.
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