Convert XLS to XLSX Free — Online & Instant

Convert XLS to XLSX — Free Online

Fast, secure, no software needed.

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How to Convert XLS to XLSX

Converting .xls files to .xlsx is fast and simple with OpenAnyFile. XLS is a spreadsheet format: XLS is the legacy Microsoft Excel binary format. XLSX is a spreadsheet format: XLSX is the default Microsoft Excel spreadsheet format.

Upload your .xls file to OpenAnyFile
Select XLSX (.xlsx) as the target format
Click "Convert" and wait for processing
Download your converted .xlsx file

Why Convert XLS to XLSX?

There are several reasons to convert from .xls to .xlsx:

Compatibility: .xlsx may be more widely supported by software and devices
File size: Converting between formats can reduce file size for easier sharing
Editing: XLSX may offer better editing capabilities for your workflow
Sharing: Recipients may prefer .xlsx files for their daily use

About XLS Format

XLS is the legacy Microsoft Excel binary format. Category: Spreadsheet. Extension: .xls. Created by: Microsoft.

About XLSX Format

XLSX is the default Microsoft Excel spreadsheet format. Category: Spreadsheet. Extension: .xlsx. Created by: Microsoft.

Frequently Asked Questions

How do I convert .xls to .xlsx?

Upload your .xls file to OpenAnyFile, select XLSX as the target, and download the converted file.

Is XLS to XLSX conversion free?

OpenAnyFile offers free file analysis. Conversion may require a one-time payment depending on the file.

Will I lose quality converting .xls to .xlsx?

OpenAnyFile preserves maximum quality during conversion. Some format-specific features may not transfer between different file types.

Can I convert .xlsx back to .xls?

Yes, you can convert .xlsx to .xls using OpenAnyFile as well.

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