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Files deleted in 5 min
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XLS
XLSX

Convert XLS to XLSX

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What is XLS?

XLS

XLS is a spreadsheet format. XLS is the legacy Microsoft Excel format, widely used for spreadsheets with calculations, charts, and data organization.

  • Category: spreadsheet
  • MIME Type: application/vnd.ms-excel
  • XLS is the legacy Microsoft Excel format, widely used for spreadsheets with calculations, charts, and data organization.

What is XLSX?

Microsoft Excel Spreadsheet

XLSX is the XML-based spreadsheet format used by Microsoft Excel since 2007. It uses ZIP compression to store worksheets, formulas, formatting, and charts in XML format. Supports advanced features like pivot tables, macros, and complex calculations with millions of rows and columns.

  • XML-based structure with ZIP compression
  • Supports formulas and calculations
  • Multiple worksheets per file
  • Charts, graphs, and pivot tables
  • Conditional formatting and data validation

Why Convert XLS to XLSX?

Software Compatibility

Work with spreadsheets across different applications

Data Exchange

Import and export data between systems and databases

Feature Access

Add or remove advanced features like formulas and formatting

File Size

Reduce file size by converting to simpler formats

⚠️ Important: Converting XLS to XLSX changes the file format while preserving content. Results depend on format compatibility and content type.

How to Convert XLS to XLSX

  1. Click the "Start Converting Now" button above
  2. Upload your XLS file or drag & drop it
  3. Select XLSX as the output format (pre-selected for you)
  4. Click "Convert" and download your XLSX file

Features

  • 100% Free Conversion
  • No Registration Required
  • Fast Processing
  • Cross-Platform Compatible
  • Secure Server Processing
  • Auto-Delete After 5 Minutes
  • Batch Processing Available
  • Mobile Friendly

Frequently Asked Questions

Can I convert multiple XLS files at once?

Yes! Free users can convert up to 3 files per batch (5 conversions/day total). Premium users get batch conversion of up to 20 files with automatic ZIP download. Simply select multiple files when uploading.

Is my data safe during conversion?

Yes! Files are processed on GDPR-compliant European servers with automatic deletion after 5 minutes. We don't store, analyze, or share your files. The conversion is secure and private.

What are the conversion limits?

Free: 5 conversions per day, max 100MB per file, up to 3 files per batch. Premium: Unlimited conversions, max 500MB per file, up to 20 files per batch with ZIP download.

How long does conversion take?

Most conversions complete in seconds. Small files (under 10MB) typically convert in 1-5 seconds. Larger files or complex formats may take 10-30 seconds. Browser-based conversions are usually faster than server-processed ones.

Do I need to install any software?

No! Everything works directly in your web browser. No downloads, no installations, no plugins required. Just upload your file and convert. Works on Windows, Mac, Linux, and mobile devices.

Ready to Convert?

Start converting your XLS files to XLSX now - it's fast, free, and secure!

↑ Convert XLS to XLSX Now