Excel to Open Source Spreadsheet: A How-To Guide

Moving from Microsoft Excel to a free, open-source spreadsheet app like LibreOffice Calc or Apache OpenOffice Calc is straightforward and saves you the cost of a subscription. This guide walks you through the entire process—from installing the software to converting your files and adjusting to the new interface—so you can switch without losing data or productivity.

What You’ll Need

A computer running Windows, macOS, or Linux.
Your existing Excel files (.xlsx, .xls) accessible on your hard drive or cloud storage.
Administrator rights to install new software (or permission from your IT department if it’s a work computer).
An internet connection to download the installer.

Step-by-Step

Choose and download an open-source spreadsheet app. The two most popular are LibreOffice Calc and Apache OpenOffice Calc. LibreOffice is more actively developed and generally has better compatibility with modern Excel files. Go to the official website (libreoffice.org or openoffice.org) and download the installer for your operating system.
Install the software. Run the downloaded installer. On Windows, double-click the .exe file and follow the prompts. On macOS, open the .dmg file and drag the app to your Applications folder. On Linux, use your package manager (e.g., sudo apt install libreoffice on Debian/Ubuntu). Accept the default installation settings unless you have a specific reason to change them.
Open your Excel file in the new app. Launch LibreOffice Calc (or OpenOffice Calc). Go to File > Open, navigate to your .xlsx or .xls file, and select it. The app will automatically convert and display the file. If you see a dialog about file format, choose “Use the LibreOffice Calc format” for editing, or “Keep the original format” if you just want to view it.
Check your formulas and formatting. Go through a few sheets and spot-check that formulas return the same results as in Excel. Pay special attention to:

Conditional formatting rules
Charts and graphs
Pivot tables
Macros (VBA code will not run; you’ll need to rewrite them in LibreOffice Basic or find an alternative)

Save your file in the new format (optional but recommended). To make the file native to the open-source app, go to File > Save As and choose the format ODF Spreadsheet (.ods). This ensures full compatibility with features like styles and formulas. If you need to share the file with Excel users, you can also save it as .xlsx—the app supports that format too.
Set the new app as your default spreadsheet program (optional). On Windows, right-click any .xlsx file, choose Open with > Choose another app, select your new app, and check “Always use this app to open .xlsx files.” On macOS, right-click the file, select Get Info, expand “Open with,” choose the app, and click “Change All.”
Learn the key differences in the interface. The menu structure is similar (File, Edit, View, Insert, Format, Tools, Data, Window, Help), but some tools have different names. For example, “Format Cells” is under the Format menu (same as Excel), but “Freeze Panes” is under View > Freeze Cells. Take a few minutes to explore the menus to find what you need.
Import your Excel templates and add-ins. If you have custom templates (.xltx), you can open them in the new app and save them as .ots (OpenDocument Template). Most Excel add-ins (.xlam) will not work; look for open-source equivalents or use built-in functions.

Common Mistakes

Assuming 100% compatibility. Complex Excel files with advanced features (e.g., dynamic arrays, XLOOKUP, or complex pivot caches) may not convert perfectly. Always review the file after opening.
Ignoring macro errors. VBA macros won’t run. If your workflow depends on them, you’ll need to rewrite them in the new app’s macro language or find a different solution.
Saving over the original file without a backup. When you save in .ods format, you’re creating a new file. Keep the original .xlsx as a backup until you’re confident everything works.
Forgetting to adjust print settings. Page breaks, margins, and print areas may shift slightly. Check your print preview before printing important documents.
Not checking for font substitution. If you use fonts not installed on the new system, they’ll be replaced, which can change the layout. Install the same fonts if possible.

Tips

Start with a copy. Before converting your entire library, test with a few representative files to see how they handle.
Use the built-in help. Both LibreOffice and OpenOffice have extensive help files. Press F1 to search for functions or features.
Learn keyboard shortcuts. Many Excel shortcuts work (Ctrl+C, Ctrl+V), but some differ. For example, in LibreOffice, Ctrl+Shift+J toggles full-screen, and Ctrl+F1 shows all shortcuts.
Explore the extension repository. LibreOffice has a large collection of extensions (e.g., for PDF import, advanced charting) that can replace Excel add-ins.
Use the “Save As” option to keep both formats. If you collaborate with Excel users, save a copy as .xlsx while working in .ods for yourself.
Convert multiple files at once. If you have many Excel files, you can use the built-in “Document Converter” wizard (File > Wizards > Document Converter) to batch-convert them to .ods.

Troubleshooting

File doesn’t open or shows an error. Try opening the file in Excel first and saving it as a new .xlsx file. Sometimes corrupted or overly complex files cause issues. You can also try the “Repair” feature in the open-source app (File > Open, then select the file and choose “Repair” from the drop-down next to the Open button).
Formulas return errors like #NAME? or #VALUE!. This usually means a function isn’t recognized. Check the function name—some have different names (e.g., STDEV in Excel is STDEV.S in LibreOffice). Use the Function Wizard (Ctrl+F2) to find the correct syntax.
Charts look broken or missing. Re-create the chart manually: select the data, go to Insert > Chart, and choose the chart type. This often fixes most issues.
Pivot tables don’t work. Pivot tables are supported, but may need to be refreshed. Right-click the pivot table and choose “Refresh.” If it still fails, delete and re-create the pivot table from the source data.
Macros don’t run. As mentioned, VBA is not supported. You can try converting simple macros using the “Basic” macro language, but complex ones will need manual rewriting. Consider using Python scripts (LibreOffice supports Python) for automation.
The app is slow with large files. Open-source apps can be slower with huge datasets. Try disabling automatic calculation (Tools > Cell Contents > AutoCalculate) and recalculate manually with F9.

Frequently Asked Questions

Will my Excel formulas work in LibreOffice Calc? Most basic formulas (SUM, IF, VLOOKUP) work identically. Some newer Excel functions (like XLOOKUP) may not be available or have different names. Check the function list in the app.

Can I still share files with Excel users? Yes, you can save in .xlsx format, which Excel can open. Just be aware that some advanced features may not round-trip perfectly.

Is there a cloud version of these open-source apps? LibreOffice offers a web-based version called LibreOffice Online, but it’s typically self-hosted. For cloud use, you might prefer Google Sheets, which is free but not open-source.

Will my pivot tables and charts convert? They often do, but not always perfectly. It’s best to check and re-create them if needed.

What about my macros? VBA macros won’t run. You’ll need to rewrite them in LibreOffice Basic or Python. Simple macros can be converted, but complex ones require manual effort.

Is LibreOffice really free? Yes, it’s free to download and use for any purpose, including commercial use. It’s developed by a community and funded by donations.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

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