XLSX to XLS Converter

Description

Convert XLSX into XLS, keeping the same spreadsheet structure and formatting while changing the underlying file format. XLS is the older format here, so convert this direction only when a recipient's software specifically requires it.

Use Cases

  • Sharing a XLSX file with someone whose software only opens XLS.

Format Comparison

FeatureXLSXXLS
CompressionYes (ZIP container)No
LayoutPreserved (styles, structure)Preserved (styles, structure)
Format eraModern (2007+)Legacy (pre-2007)

Example Workflow

  1. Upload your XLSX file.
  2. Click “Convert to XLS.”
  3. Download the resulting XLS file.

Complete Guide to XLSX to XLS Conversion

What is XLSX to XLS Conversion?

Transforms modern Excel (XLSX) files into legacy Excel (XLS) format, downgrading OpenXML spreadsheet files to the binary format for compatibility with older Microsoft Excel versions and legacy systems.

Why Convert XLSX to XLS?

  • Legacy Excel 97-2003 compatibility requirements
  • Corporate environments with older Excel versions
  • Support for legacy macro and VBA requirements
  • Compatibility with older business systems
  • Ensure file accessibility across all Excel versions

Technical Specifications

AspectXLSX FormatXLS Format
File TypeOpenXML spreadsheetBinary spreadsheet
CompatibilityExcel 2007+Excel 97-2003
File SizeCompressed XML formatLarger binary format
FeaturesModern Excel featuresLegacy Excel features

Best Practices

Before Conversion
  • Test formulas and calculations
  • Check for modern Excel features
  • Verify data integrity
  • Document any advanced features
  • Create backup of original XLSX file
After Conversion
  • Verify formulas work in legacy Excel
  • Test with Excel 97-2003
  • Check for feature compatibility issues
  • Validate calculations and formatting
  • Test with target legacy systems
Conversion Stats
  • Success Rate: 90%
  • Avg Processing: 2–4 seconds
  • Max File Size: 50MB
  • Formula Compatibility: Good
XLS Format Benefits
  • ✓ Legacy Excel compatibility
  • ✓ VBA and macro support
  • ✓ Corporate system integration
  • ✓ Familiar Excel interface
Related Tools

About XLSX and XLS

XLSX (Microsoft Excel Workbook (Office Open XML)) is Excel's modern XML-based format, supporting formulas, multiple sheets, charts, and conditional formatting.

XLS (Microsoft Excel 97-2003 Workbook) is Excel's legacy binary format, still common on older systems though superseded by XLSX.

What to expect: XLSX and XLS support similar formatting, so most content and structure should carry over cleanly.

Related Conversions

XLS to XLSX XLSX to DOC XLSX to DOCX XLSX to ODT XLSX to RTF XLSX to PDF

Frequently Asked Questions

Yes. Your file is processed on our servers to perform the XLSX-to-XLS conversion, and the download link is private to your session — it isn't published or indexed anywhere.

No. The XLSX to XLS conversion runs entirely in your browser and on our servers — nothing to download or install.

Yes, files up to 51MB are supported for XLSX to XLS conversion.

Most formatting carries over cleanly for standard documents. Files with heavy custom formatting, macros, or unusual layout may need a quick manual check after conversion, since XLSX and XLS don't support identical feature sets.

No signup, no account, and no payment required to convert XLSX to XLS.