document conversion
XLS to XLSX Converter
Convert XLS files to XLSX online for free. Upload a XLS file, choose XLSX, and download the converted file with no account required.
Conversion details
Start with XLS
legacy spreadsheets and older Excel workbooks
Export as XLSX
modern spreadsheets, tables, and workbook sharing
Before you share
XLSX is the modern Excel workbook format. Keep the original XLS file until the converted XLSX opens correctly where you need it.
When this converter is the right fit
Best XLS source files
legacy spreadsheets and older Excel workbooks
When XLSX is the right output
modern spreadsheets, tables, and workbook sharing
What to verify before sharing
XLSX is the modern Excel workbook format. Open the converted file and keep the original XLS until the XLSX result works where you need it.
File handling checklist
- Start without creating an account.
- Use the exact XLS to XLSX route from this page.
- Upload .xls files and expect .xlsx downloads.
- Batch uploads must use the same input extension.
- Review the output before replacing your source file.
- If the destination app rejects the result, try a related output format below.
Download and handoff plan
Confirm the downloaded extension
This route is expected to produce .xlsx files. If your browser or destination app renames the file, check the download name before uploading it.
Test the destination before deleting the source
Open the XLSX output in the app, form, player, editor, or device that requested it, then keep the original XLS until the final upload or handoff succeeds.
Use a related converter when requirements change
If the destination rejects .xlsx, use the related converter links on this page instead of renaming the file extension by hand.
Where this output works best
Use XLS to XLSX when your destination needs modern spreadsheets, tables, and workbook sharing.
Good destinations
- School portals, job applications, office editors, email, print, and archive handoffs
- PDFs, Word files, spreadsheets, slides, scans, and document-style uploads
- Workflows that need either stable layout, editable text, extracted pages, or table review
Output checks
- Review page breaks, tables, images, links, headers, footers, and editable text.
- Confirm whether the destination needs a stable PDF, editable DOCX, plain text, or image output.
- Keep the source document until the converted file opens and uploads correctly.
Accepted files and output for this route
Upload extensions
This converter accepts .xls files for the XLS input.
Download extension
Results are prepared as .xlsx files for the XLSX output.
Batch plan
Add up to 10 files at once, and keep each batch to the same input extension so every item uses this exact route.
Practical XLS to XLSX workflow
Convert XLS files in one focused route
Use this page when your source files are XLS and every selected file should become XLSX. Batch selection works best when the files share the same input extension.
Choose XLSX for the destination app
XLSX is a good fit for modern spreadsheets, tables, and workbook sharing. If the app or upload form asks for a different file type, use the related converters on this page instead.
Keep a verified original
XLSX is the modern Excel workbook format. Keep the original XLS until the converted XLSX opens, uploads, or plays correctly in the final destination.
Verification checks
- Confirm the source file is really XLS, not just renamed with a different extension.
- Use XLSX only when the destination accepts that format.
- review page breaks, tables, links, images, and editable text
- Keep the original file until the converted output is accepted.
Choose the right output before converting
Use XLSX when the destination asks for it
XLSX is the right choice when your office editor, school portal, job form, client review, archive, or print workflow accepts XLSX and you need modern spreadsheets, tables, and workbook sharing.
Keep XLS when source quality matters
XLS is the older Excel format and is often converted to XLSX, CSV, or PDF. Keep the source file until the converted XLSX passes the final upload, playback, or review check.
Switch output if the result is rejected
If XLSX is not accepted, try a related format instead. Common fallbacks for this route are PDF for stable sharing, DOCX for editing, TXT for plain text, or XLSX for tables.
Why convert XLS to XLSX?
Document formats differ in editability, layout stability, table support, and sharing compatibility. XLS files are commonly used for legacy spreadsheets and older Excel workbooks. Converting to XLSX helps when your next tool, device, website, or sharing workflow needs modern spreadsheets, tables, and workbook sharing.
Best uses for XLSX
XLSX is useful for modern spreadsheets, tables, and workbook sharing. XLSX is the modern Excel workbook format. Use this output when compatibility, editing needs, upload requirements, or file size make XLSX the better fit.
Before you convert
Check page order, fonts, spacing, tables, links, images, and whether the converted file opens correctly in your target app. Keep the original XLS file until the converted XLSX file has been reviewed successfully.
Common upload errors this can fix
Use this converter when an upload form says the file type is not supported, when an app cannot preview the XLS file, or when a recipient needs a more familiar XLSX file. Always match the output to the format requested by the destination, especially for job portals, school submissions, marketplace listings, CMS uploads, and social platforms.
XLS vs XLSX
XLS is commonly used for legacy spreadsheets and older Excel workbooks. XLSX is commonly used for modern spreadsheets, tables, and workbook sharing. The best choice depends on whether you need compatibility, editing support, smaller file size, stable layout, transparency, playback support, or a format that a specific upload form accepts.
Conversion checklist
After converting, open the XLSX file before deleting the original XLS. Check file size, readability, playback or preview behavior, and whether the converted file works in the exact app, website, or device where you plan to use it.
XLS to XLSX FAQ
How do I convert XLS to XLSX?
Upload your XLS file, keep XLS as the input format, choose XLSX as the output, then start the conversion and download the converted file.
Is this XLS to XLSX converter free?
Yes. You can convert files online without creating an account or installing desktop software.
When should I use XLSX?
XLSX is useful for modern spreadsheets, tables, and workbook sharing. XLSX is the modern Excel workbook format.
Will converting XLS to XLSX change quality?
Quality depends on the source file and output format. XLS is the older Excel format and is often converted to XLSX, CSV, or PDF. XLSX is the modern Excel workbook format.
Why would a website reject my XLS file?
Many upload forms accept only a short list of formats. If the form asks for XLSX, convert the file first, then open the result and confirm the upload accepts it.
Should I use XLSX for final sharing?
XLSX is useful when the destination needs that format. Use PDF when the document is final and layout stability matters most.
What document details should I review?
Check page breaks, fonts, tables, images, links, headers, footers, and whether scanned text needs OCR before relying on the converted file.