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Convert .XLS to .XLSX

This guide explains how to convert .XLS files to .XLSX and provides information about both file formats.

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About .XLS files

.XLS identifies a document file format used by specific applications and workflows. This guide helps you open it safely across devices.

.XLS files are commonly used as document files and can be opened with compatible software on major platforms.

Learn more about .XLS files

About .XLSX files

XLSX is the default Excel workbook format based on Office Open XML. It packages worksheet XML and assets inside a ZIP container.

XLSX files store spreadsheet data, formulas, charts, and pivot tables.

Learn more about .XLSX files

Conversion tools

These tools support converting .XLS to .XLSX.

ConvertAPI

ConvertAPI is an enterprise-oriented file conversion REST API with per-converter OpenAPI schemas that specify allowed input extensions and target formats for each conversion endpoint.

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