Links to other workbooks that nothing reads
Safe. On by default.
Removes links to other workbooks that nothing in the file uses.
Why it takes space
When a formula reads a cell in another workbook, Excel stores a link to that file and a copy of every value it reads from it, so it can show them while the other file is closed.
A link can remain after nothing in the workbook uses it any more. Its copy of values stays in the file, and Excel still asks whether to update it when the file opens.
What ShrinkExcel does
ShrinkExcel reads every cell formula, defined name and chart series. When none of them reads another workbook, it removes every link and each link's copy of values.
When anything reads even one link, it leaves all of them in place. Break links handles that case, and starts off.
It leaves a workbook with macros alone, because a macro may read a link. It also leaves alone a workbook with a DDE or OLE link, one that mentions another workbook in data validation, conditional formatting or a drawing, and one that calculates iteratively.
What you will notice
Nothing on the sheets changes, since no cell, name or chart read the links. Excel stops asking whether to update links when the file opens.
Doing it in Excel
Excel drops links that nothing reads when it saves the workbook. In a check in Excel for Mac on 2026-09-24, saving five such workbooks in Excel removed the same links ShrinkExcel removes, and every cell matched.
Data > Edit Links lists the links a workbook has. Newer versions of Excel call it Workbook Links.
It runs on every workbook you drop on the front page, unless you switch it off under Advanced settings.