How to Reduce a Large Excel File
Excel 2007 or 2010 is a great tool for data analysis but can grow in size quickly. Another problem is when you are connected to a database and you reduce the size of a query in the database view; the reduction in data is not reflected in Excel as the latter keeps an internal table of the data, especially when working with Pivot Tables that are linked to the database.
There are several techniques that you can use to reduce the size of an overbloated Excel file that I will review in this reference article.
Excel copies and stores data for each worksheet that is created in an Excel workbook. Even if you use external data from another spreadsheet or database, each sheet will have a copy of the data. You should review the different worksheets in a workbook to see if some can be deleted or combined to reduce space.
Eliminating excess worksheet, thus data bloat, will greatly reduce the size of your file and increase performance. Also be careful about links to other worksheets with a lot of formulas or to other worksheets in external workbooks. While this won't necessarily change the size of the workbook, it will impact performance which can be as problematic as bloated data.
Converting to Binary
Another technique that can substantially reduce the size can be used in conjunction the previous technique of consolidating and deleting old worksheets is to convert the Excel file to a binary format which is represented by the file extension xlsb. You won’t lose any functionality and you will actually gain some performance.
To convert a 2007, 2010 or greater Excel file to a binary format, follow these simple steps.
- With the Excel file open
- Click on the File tab (Fig 1)
- Select “Save AS” from the Tab menu
- In the Save As dialog select the “Save As Type” dropdown field and select the “Excel Binary Workbook (*.xlsb)” option from the list of values. See figure 2.
- Click Save
You notice notice a huge size file savings and an increase in performance by using the binary format. However, the trade off you won’t have access to the XML files in the Xlsx archive. See Figure 3.
Compacting Excel File
While not directly related to Excel, Windows has a feature that will compact the size of a file, including Excel.
To compact your Excel file, locate the your file via Windows Explorer
- Right click the file
- Select Properties from the context menu
- Next Select the Advanced button (see Figure 4 below)
- Finally select “ compress contents to save disk space...”
These techniques can be used separately or together to help you reduce the file size of your Excel files.