Equations are randomly re-sized in Word

TechNote 150
The information on this page applies to:
MathType for WindowsMicrosoft Word 2007 and later (Windows)

You have created a Word document with several MathType equations. It looked great at the time, but when you opened it a week later, the equations are now different sizes — some smaller, some larger, most with a random height:width ratio.

Our investigation reveals there's nothing you or MathType are doing to cause this; it's being caused by Word. This bug affects not only MathType equations in Word, but other embedded objects such as charts and pictures. Below, we'll describe the process to fix the equation display ratio and to minimize the possibility of it happening in the future.

The first step in the solution is to upgrade to the most recent version of MathType, because the repair process below will go smoother than if you're using an earlier version. You can download the latest version from our downloads page. If you have a MathType subscription already, this is a free upgrade and you should not have to enter your product key during installation. No need to uninstall your current version, just install the new one on top of it. If you're licensed for a version earlier than 7.0, you might want to install it as a 30-day trial first.

Equations after Word re-sizes them

Run the Convert Equations command

In the MathType tab on Word's ribbon, there's a command named Convert Equations. It may seem that since it's the formatting that's off, and not something else, then "Format Equations" would be more appropriate. That is, in fact, logical but in this case it's indeed "Convert Equations" you need. Click that, and the Convert Equations dialog will open:

MathType's "Convert Equations" dialog in Word.

Of the 4 checkbox selections on the left, you need at least the top one checked, and possibly the 4th one, as shown here. If it's your document, and you know you didn't use Word's equation editor for any of the equations, just select the top one. In the "Convert equations to" section on the right, ensure the selected button is as shown here. Click Convert and wait for the process to complete.

Notes and recommendations

  1. PLEASE VOTE! This is a Microsoft bug and only Microsoft can fix it! Many people think that since Wiris is a software company, we must have a more direct voice to Microsoft that will make a bigger difference than a lone customer. This is incorrect. Microsoft listens to their customers because it's from you that they get their income. Please report this issue to Microsoft! It is only by doing so that it will get fixed. Here's how to do that:
    • UserVoice. This is Word's Suggestion Box. There is already a report filed, so rather than file your own, it's much easier to just vote on this one. Once you click the Vote button, you'll have to enter an email address, but it can be a one-time email address if you want. (Advantage of signing in with a real email address is that you can opt to get reports from Microsoft when the status changes for this or other issues.) Here's the issue to vote on.
  2. Work on a copy of the document, not on the original. When the process is finished and you've verified things are as you'd like, you can save the copy with the original document's name and work with this one as your new "original".
  3. Word doesn't handle large documents well. If your document is larger than 10 pages, or if it contains more than 100 equations, this process will work best if you run Convert Equations on one section of the document at a time. "Select" part of the document either by dragging the mouse across the text, or any other means of selection that you're familiar with, then choose the Current selection option in the Range section of the dialog. Repeat the process on the next section of the document until you've converted the entire document.
  4. Scan and spot check the document because sometimes Word will have corrupted an equation or two (or more), and these may now be missing from the document.


We hope this has been helpful. As always, please let us know if you have questions about this, or if you have additional techniques that work. We'd love to hear from you.