How to Compress Excel Files – Without Third-Party Software

Written by co-founder Kasper Langmann, Microsoft Office Specialist.

A simple rule is that the more data you have, the heavier the Excel file will be.

There’s no going around with that.

However, there surely are ways to help you compress your Excel files without using third-party software or platforms.

In this article, let’s tackle four ways to compress an Excel file without risking your file’s security.

Kasper Langmann, Co-founder of Spreadsheeto

Let’s get started!

*This tutorial is for Excel 2019/Microsoft 365 (for Windows). Got a different version? No problem, you can still follow the exact same steps.

Save as Excel Binary File Format

Excel Binary File Format (.xlsb) is a collection of records and structures that specific Excel workbook content.

Here’s how Microsoft defines the XLSB format in their documentation:

Microsoft documentation of Excel binary file format

Compared to XLSX, XLSB files can be read and written faster which makes it ideal when working with large files.

The reason why some people don’t use XLSB is that if the file is in such format, you couldn’t tell if it has a macro or not.

As you may know, macros could be a source of malicious code.

The bottom line is, only save your Excel file in XLSB format if you’re the only one who will have to use the file or with someone that you trust.

Kasper Langmann, Co-founder of Spreadsheeto

To save your Excel file in XLSB format, simply select it from the options.

How to save an Excel file as a binary file

Here’s a comparison of the same worksheet with the same data saved in different formats:

The difference of saving an Excel file as a binary file

That’s 82% size reduction! Nice! 😊

Delete unnecessary data

The more data you have, the bigger the file size will be.

So if you want to compress the size of your Excel file, you could double-check your data and find unnecessary data you could delete.

Kasper Langmann, Co-founder of Spreadsheeto

For example, after deleting two tabs on the sample file, here’s the result:

The difference after deleting unnecessary data

This is a great way to compress files while cleaning your data.

The principle here is simple — remove what you don’t need. 😊

Delete the pivot cache

Pivot table skills are one of the most highly sought after skills since only a few Excel users exactly know what they are and how to create one.

To be precise, a pivot table is a built-in feature in Excel that enables you to take data and re-arrange it by creating a table.

In this table, you can then choose what and how you want to see your data.

How to compress an Excel file by deleting the pivot cache

Unfortunately, creating a pivot table also takes up space especially when you have a larger data set.

The reason for this is that Excel automatically creates a pivot cache that holds a copy of the data source.

Pivot cache helps make your workbook run smoothly since it doesn’t have to generate the entire data set in a worksheet every time you open your file.

Kasper Langmann, Co-founder of Spreadsheeto

To delete the pivot cache, all you have to do is disable its setting.

Here are the first steps:

  • Select the pivot table
  • Go to the ‘Analyze’ tab on the ribbon
  • Click the ‘Options’ button on the ‘PivotTable’ group
How to change the options of a pivot table

Then, head over to the ‘Data’ tab on the window.

Here, all you have to do is untick the ‘Save source data with file’ box and tick the ‘Refresh data when opening the file’ box.

Don’t forget to click on the ‘OK’ button.

How to disable pivot cache saving

The second box will make sure that the Pivot Table is refreshed and the cache generated every time you open the workbook.

After that, you will now see a smaller file size compared to when the cache was active.

The difference after deleting an Excel file’s pivot cache

The bigger your data set, the more noticeable the gap will be.

Compress (zip) the file itself

This option is not native to Excel since almost any file can be zipped.

When you zip a file, you can expect around 10% to15% file reduction.

Before, it’s hard to zip a file since you will have to download and use zipping software. Now, however, Windows supports zipping a file right from its windows explorer.

Kasper Langmann, Co-founder of Spreadsheeto

Here are the steps:

  • Right-click on the file
  • Hover your mouse over ‘Send to’
  • Click ‘Compressed (zipped) folder’
How to save an Excel file as a zipped folder

Here’s the result:

The difference in size after saving a file in zip format

Wrapping things up…

As you can see, there are different ways to compress an Excel file without risking your data. Everything listed on this list is free and doesn’t use any third-party options.

There are still other ways to compress an Excel file. However, we find these four methods to be extremely effective.

Remember, the more data you have, it’s expected that you will have a larger file size too.

Kasper Langmann, Co-founder of Spreadsheeto