If you’ve ever received an XLSX file by email or downloaded one from the internet, you might not know what it is. Unlike a PDF or a Word document, the XLSX extension isn’t instantly recognizable for many people.
These files are actually very common. They’re created by Microsoft Excel and used to store spreadsheets, but the good news is you don’t need Excel alone to open them.
What Is an XLSX File?
An XLSX file is a spreadsheet file created by Microsoft Excel, part of the Microsoft Office and Microsoft 365 suite. It uses the Office Open XML format, which means it’s structured with XML (Extensible Markup Language) and compressed to reduce file size.
Inside one XLSX file, you can find multiple worksheets, rows, columns, formulas, charts, pivot tables, and formatting. It’s the standard file type used for data management, financial records, business reports, and many personal projects like budgets or schedules.
XLSX vs XLS: What’s the Difference?
Before 2007, Excel used the .XLS extension, which was based on a binary format. Since Excel 2007, Microsoft introduced .XLSX, the XML-based format.
- XLS: older, larger, more prone to corruption.
- XLSX: newer, smaller, less likely to break, more secure.
XLSX is now the default format in modern versions of Excel, though Excel can still open and save in XLS for compatibility.
Programs That Open XLSX Files
You don’t need Microsoft Excel to open an XLSX file. Many tools support the format:
- Microsoft Excel – best option, available on Windows, Mac, and Microsoft 365.
- Google Sheets – free, works directly in your web browser.
- LibreOffice Calc – open-source alternative for Windows, Mac, and Linux.
- Apple Numbers – built-in option for Mac, iPhone, and iPad users.
- Zoho Sheet or Office Online – online spreadsheet editors that support XLSX.
How to Open XLSX on Windows and Mac
Opening an XLSX file on a computer is usually straightforward. If you already have Microsoft Excel installed, a simple double-click will launch the file and display it in Excel with all its formatting, formulas, and worksheets intact.
If you don’t have Excel, there are still plenty of alternatives. You can right-click the file, choose Open With, and select another program such as LibreOffice Calc on Windows or Apple Numbers on macOS. Both support XLSX files and can handle most spreadsheet functions without issue.
Another option is to use the cloud. By uploading the file to Google Drive, you can open it directly in Google Sheets by dragging and dropping the file into your browser. This method works on any operating system and is completely free, making it a convenient solution when Excel isn’t available.
How to Open XLSX on Mobile (iOS and Android)
Opening an XLSX file on a smartphone or tablet is just as simple as on a computer. The easiest option is to download the Microsoft Excel app from the App Store or Google Play. It opens spreadsheets in their native format and keeps the familiar Excel layout.
If you prefer a cloud-based tool, the Google Sheets app is a great choice. It connects directly to your Google account, lets you upload XLSX files to Google Drive, and makes editing possible from any device with internet access.
For iPhone and iPad users, Apple Numbers is another alternative. It can open and edit XLSX files natively, though some advanced Excel features may not carry over perfectly. Still, it works well for basic spreadsheets and quick edits.
No matter which option you choose—Excel, Google Sheets, or Apple Numbers—you’ll be able to view and edit spreadsheets on the go without needing a desktop computer.
How to Convert an XLSX File
Sometimes you’ll need to share an XLSX file in another format.
- Save as PDF if you only want others to view, not edit.
- Export as CSV if you need plain-text data for databases.
- Save as XLS if you need compatibility with older Excel versions.
- Use online converters (with caution for sensitive data) if you don’t have Excel or a spreadsheet app installed.
Troubleshooting XLSX Files That Won’t Open
If an XLSX file won’t open, don’t panic. Common problems include:
- File corruption – in Excel, use the “Open and Repair” feature.
- Wrong extension – check if the file is actually XLSM, CSV, or ODS.
- Outdated software – install the latest updates for Excel or try free alternatives like Google Sheets or LibreOffice.
Final Thoughts
An XLSX file is simply a modern Excel spreadsheet, built on XML for better performance and reduced file size. While Excel is the most powerful tool for working with it, you can also open and edit these files with free options like Google Sheets or LibreOffice Calc.
Whether you’re on Windows, Mac, iPhone, or Android, there’s always a way to view and work with XLSX files without stress.
- What Is an XLSX File and How to Open It - September 25, 2025
- How to Connect a Speaker to Samsung Odyssey G8 Monitor? - September 15, 2025
- How to Fix Error 503 Backend Fetch Failed on Websites and Apps? - September 10, 2025