Online XLS Converter
Convert, merge, and split your spreadsheet files between different formats quickly and easily
Drop your Excel file here and convert it instantly
Accepted formats: .xlsx, .xls
Size up to 100MB
Files deleted automatically
Secure upload (SSL)
XLSX to XLS
Convert modern Excel files to legacy format for compatibility with older Excel versions
Convert XLSX to XLSXLS to XLSX
Upgrade legacy Excel files to modern format with improved features and smaller file size
Convert XLS to XLSXXLSX to ODS
Convert modern Excel files to OpenDocument format for full compatibility with LibreOffice and OpenOffice.
Convert XLSX to ODSXLS to ODS
Transform legacy Excel 97-2003 spreadsheets into open-source friendly ODS files while keeping all data intact.
Convert XLS to ODSXLSX to CSV
Quickly extract data from modern Excel spreadsheets into comma-separated values.
Convert XLSX to CSVXLS to CSV
Convert legacy Excel 97-2003 files format for database imports and data analysis.
Convert XLS to CSVXLSX to HTML
Convert modern Excel spreadsheets into clean, responsive HTML tables for web pages and emails.
Generate HTML CodeXLS to HTML
Transform legacy Excel 97-2003 files into structured HTML5 markup while preserving cell data and styles.
Generate HTML CodeSplit Excel by Sheets
Automatically extract every worksheet into a separate file. Perfect for massive workbooks up to 100MB.
Extract All SheetsMerge Excel Files
Combine multiple spreadsheets into one workbook. Supports large files up to 50MB with styles preserved.
Start MergingPowered by LibreOffice Technology
Built on Open-Source LibreOffice
Our tools are powered by LibreOffice, a widely used open-source office suite. That means conversions behave like a real spreadsheet app - without you installing anything.
Accurate Results Across Formats
We focus on the details people care about: values, formulas, sheets, and formatting. For conversion and splitting we support files up to 100MB, and for merging we support up to 50MB per file.
Reliable and Free
No registration required. Processing runs on our server for stable, repeatable results, and temporary files are cleaned up automatically after each job.
How to Convert
Convert your Excel files in 4 simple steps. It's fast, secure, and free!
Select Conversion Type
Choose the format you want to convert to from our conversion options
Upload Your File
Drag & drop your Excel file or click to browse. We support XLS, XLSX, and more
Wait for Processing
Our system will convert your file. This usually takes just a few seconds
Download Result
Your converted file will download automatically in your browser
Why Choose Our Excel Converter
Experience the best Excel conversion tool with these amazing benefits
No Registration Required
Start converting immediately without creating an account
Large File Support
Convert files up to 100MB in size. Our engine is optimized for heavy data
Secure Processing
Your files are protected with 256-bit SSL encryption and automatically deleted after processing
Unlimited Conversions
Convert files without daily limits or subscription requirements
100% Layout Precision
We preserve every cell style, border, and formula. Your XLS looks exactly the same after conversion
Multiple Languages
Supports Excel files in various languages and character encodings without data loss
Convert Excel Files Online Without Installing Anything
You don't need to install expensive office software just to convert a spreadsheet — our online tool handles XLS, XLSX, CSV, ODS, and HTML files right in your browser. Upload your file, pick the output format, and download the result in seconds, with all formulas and formatting preserved.
Need More Power?
While our online tool is great for quick tasks, our Desktop Version offers pro features for power users.
Frequently Asked Questions
Our engine is optimized for heavy data. You can comfortably upload and convert spreadsheet files up to 100MB without performance drops or freezes.
Yes. The converter perfectly retains your original layout, including custom cell formatting, borders, colors, and complex formulas during the XLS/XLSX conversion process.
Absolutely. All file transfers use end-to-end SSL encryption. Your files are processed automatically and are permanently deleted from our servers after conversion.
If you don't have specialized Excel software, XLS Converter Online can help. With our converter, you can convert your file to simpler formats, such as CSV.
Yes. Our converter is designed to work smoothly on mobile devices. There’s no need to download or install any app — just open your mobile browser (Safari, Chrome, etc.) on your iOS or Android device, go to our website, and use the converter as you would on a computer.
Currently, we support XLSX, XLS, CSV, HTML, and ODS. You can convert these formats to each other where applicable, and we plan to add more formats in the future.
Yes. When converting XLS to XLSX or XLSX to XLS, we preserve cell styles, fonts, colors, borders, number formats, formulas, multiple worksheets, merged cells, row heights, column widths, and overall workbook structure. In most cases, your file will look and behave the same after conversion.
An Excel converter is a tool that changes spreadsheet files from one format to another. It can transform Excel files (XLS, XLSX) into formats like HTML, CSV or ODS. Our online Excel converter runs in your browser, supports batch conversion where available, preserves the original layout as much as possible, and requires no installation or registration.
Question of the Day
Today's tip: Use the 'Text to Columns' feature in Excel to split data from one column into multiple columns based on delimiters like commas, spaces, or tabs.