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Convert EXCEL to XLSX Online


1) Upload EXCEL file to convert

 

Drop files here, or Click to select
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Allowed file types: fasta, qif, ofx, iif, srt, ics, excel, ris, bib, ods, xls, xlsx, xlsm, csv, tsv, tab, xlsb, xltx, xlr, pxl, qpw, wb3, wq1, dbf, wk3, 123, mdb, evtx, pages, numbers, sqlite

2) Set converting EXCEL to XLSX options

Convert to

 

Options

Header:
Footer:

3) Get converted file

DOWNLOAD CONVERTED FILE
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Get Total Excel Converter to convert XLS, XLSX, ODT, XLSM, etc. safely.

Excel Converter To Convert Spreadsheets
  • Convert Excel Files in Batch!;
  • Convert EXCEL to XLSX and in many other formats
  • Convert hundreds of spreadsheets in 3 clicks;
  • Both MS Office and OpenOffice files;
  • Have a desktop converter that works without Internet;
  • Keep your files safe, don't send them to the web;
  • Get more accurate results with the more poweful engine.
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close Total Excel Converter
okTotal Excel Converter supports almost all Excel extensions: XLS, XLSX, XLSM, XLSB, XLT, XLTM, XLTX, XLK, XLW. When the new Office is released, we will add new file types too.
okWith Total Excel Converter you can convert Excel to PDF and add a digital signature in one go.
okTotal Excel Converter can convert each page of your spreadsheet into a separate file.
okTell Total Excel Converter to copy original time stamps if you don't want to change the date.
okHave an outdated Microsoft Office 2003? Update all your old files to the new format in one go. Convert XLS files to XLSX in batches.
okTotal Excel Converter will help you to convert Excel 2003 XML Files (rare option!)
okTotal Excel Converter has a built-in renamer to give your files new descriptive names. Include a counter, a date or worksheet name into the file name and your files will be in perfect order.
okConvert Excel spread sheets via our most straightforward interface.
okThe widest list of output file types: DOC, PDF, HTML, MHT, XHTML, CSV, TXT, TIFF, JPEG, SVG, RTF, XML, XLS, XLSX, ODS, ODT, Lotus, DIFF, SYLK, LATEX, SQL, DBF, Access!
okTotal Excel Converter can combine several Excel spread sheets into one TIFF or PDF file.
okWant to quickly find a file? Total Excel Converter helps you to preview any document you select.
okAdd your logo or any other image to the header or the footer of the output file.
okWant more order? Add page counters or a date to every page of the output files. Sequential numbering of several folders is avaialble.
okTotal Excel Converter can copy original time stamps if you want to keep them.
okWhen you convert Excel to PDF you can set user permissions, password-protect your files or sign with a digital signature. Get PDF, PDF/A and non-searchable PDFs.
okTotal Excel Converter can be run via command line (get the ready-to-use command line from GUI).

How to convert EXCEL to XLSX?

1

💾 Upload Your File: Go to the site, click on «Upload File,» and select your EXCEL file.

2

✍️ Set Conversion Options: Choose XLSX as the output format and adjust any additional options if needed.

3

Convert and Download: Click 👉«Download Converted File»👈 to get your XLSX file.

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Cloud Based
Convert EXCEL to XLSX without installing Excel or a spreadsheet app. Upload the file in your browser and download the XLSX on Windows, Mac, or mobile.
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Secure
Spreadsheets can contain names, figures, and contact details. Your EXCEL upload is encrypted in transit with HTTPS/TLS and processed in data centers with multi-factor access control during the conversion to XLSX.
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Ease of Use
Converting from EXCEL to XLSX has never been so simple. Our intuitive interface lets you convert files in just a few clicks.
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Privacy
The contents of your EXCEL are never inspected or reused. After the conversion to XLSX, both files are deleted automatically from our servers. Privacy Policy.

 

XLSX File

File extension .EXCEL, .XLSX
CategoryDocument File
DescriptionXLSX is a format from Office Open XML family, a native MS Excel file type starting from version 2007. As opposite to XLS, this format uses ZIP compression that makes XLSX files smaller in size. Actually XLSX file is an archive of XML-documents. The cells in XLSX table can contain plain text, formulas or graphic elements. XLSX can be read in MS Office 2007 and later, Universal Viewer, OpenOffice, MS Office Excel Viewer, Corel WordPerfect Office. This format doesn’t support macros.
Associated programsMicrosoft Excel 2007
OpenOffice
OxygenOffice Progessional (Linux)
Developed byMicrosoft
MIME type
Useful links
Conversion typeEXCEL to XLSX

XLSX File

File extension .XLSX, .EXCEL
CategoryDocument File
DescriptionXLSX is a format from Office Open XML family, a native MS Excel file type starting from version 2007. As opposite to XLS, this format uses ZIP compression that makes XLSX files smaller in size. Actually XLSX file is an archive of XML-documents. The cells in XLSX table can contain plain text, formulas or graphic elements. XLSX can be read in MS Office 2007 and later, Universal Viewer, OpenOffice, MS Office Excel Viewer, Corel WordPerfect Office. This format doesn’t support macros.
Associated programsMicrosoft Excel 2007
OpenOffice
OxygenOffice Progessional (Linux)
Developed byMicrosoft
MIME type
Useful linksMore detailed information on XLSX files
Rating EXCEL to XLSX   5 star EXCEL to XLSX   4.9 (2232 votes)
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Excel to XLSX Converter — Frequently Asked Questions ▼

When would I need to convert an XLS file to XLSX?

XLS (Excel 97–2003 binary format) has a hard limit of 65,536 rows and 256 columns per sheet, and it lacks support for features introduced in Excel 2007 and later — such as larger color palettes, sparklines, advanced conditional formatting, and table slicers. Converting to XLSX removes those restrictions and makes the file compatible with current Excel, LibreOffice, and Google Sheets without compatibility-mode warnings.

What is preserved during XLS to XLSX conversion?

Cell values, all standard formulas, named ranges, charts, pivot tables, data validation rules, cell styles, borders, fonts, and number formats are all carried over. Macro-enabled workbooks (.xls with VBA) become .xlsx without macros, since XLSX does not store VBA code — if you need macros, save as .xlsm instead.

Does the file size change after conversion?

Yes, XLSX uses ZIP-compressed XML internally, so the converted file is typically 20–50% smaller than the equivalent XLS binary file. A 5 MB XLS workbook with mostly text and numbers commonly converts to a 1–2 MB XLSX. Workbooks dominated by embedded images see less size reduction.

Will the converted file open correctly in older versions of Excel?

XLSX requires Excel 2007 or later to open natively. Excel 2003 can open XLSX files if the Microsoft Office Compatibility Pack is installed. If your recipients use Excel 2003 without the compatibility pack, keep the XLS version for them.

What is the file size limit for the online converter?

Files up to 50 MB are accepted online. Most XLS workbooks are well within this range. For very large files or automated batch upgrades of an entire folder, use the desktop Total Excel Converter: TotalExcelConverter.exe C:\Old\*.xls /xlsx /out C:\New\.

Can I upgrade an entire folder of XLS files to XLSX at once?

The online converter handles one file at a time. The desktop Total Excel Converter processes whole directories in one pass: TotalExcelConverter.exe C:\Legacy\*.xls /xlsx /out C:\Upgraded\. A 30-day free trial is available without email registration.
 

 

EXCEL to XLSX Online Conversion Tool

The EXCEL to XLSX Converter offers a seamless and efficient solution for users who need to upgrade their Microsoft Excel files to the more advanced XLSX format. This conversion is particularly beneficial for those looking to enhance file compatibility, reduce file size, and leverage the improved functionality that comes with the XLSX format. While older Excel files with the .xls extension can still be used, converting to .xlsx ensures that users can utilize the latest features and functions offered by Microsoft Excel, optimizing both performance and user experience.

The process is simple and straightforward. Users can upload their existing Excel files directly through the browser, without the need for installing any additional software. The tool processes the conversion swiftly, maintaining the original formatting and data integrity. This ensures that the converted files are ready for immediate use, whether for work, school, or personal projects.

What sets our EXCEL to XLSX converter apart from others is its user-friendly interface and commitment to security and privacy. We guarantee that your files are processed with utmost confidentiality and are deleted from our servers after conversion. Additionally, there are no hidden costs or limitations on the number of files you can convert, making it an ideal choice for both individual and business users who require reliable and cost-effective conversion solutions.

Feature Online Converters CoolUtils Desktop Excel Built-in Other Software
Batch Conversion Limited ✅ Unlimited Manual only Limited
File Size Limit 1-5MB ✅ No limits System dependent Varies
Privacy & Security Upload required ✅ 100% offline ✅ Local only Varies
Conversion Speed Internet dependent ✅ Fast local processing Slow Medium
Advanced Options Basic ✅ Full customization Limited Basic
Cost Free/Premium One-time purchase Requires Office Subscription
Formatting Preservation Good ✅ Excellent Good Varies
Multiple Formats Support Limited ✅ 40+ formats Few formats Limited

Convert from EXCEL

Using CoolUtils, it is possible to convert EXCEL files to a variety of other formats:

Convert to XLSX

Using CoolUtils, it is possible to convert a variety of other formats to XLSX files:

                                                                                                 

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