How to Change the Mail Font Size in Mac OS X

The default font size in the Mail app for Mac OS X is size 12 for emails and messages that are lacking styling, which tends to be most communications that are sent by email.

If you find the font size in Mail for Mac to be too small, or even too big, you’ll be pleased to know that changing the text size of email messages is quite simple. Not only can you change the font size for the email content itself, but also for other components of an email message, including the sender, recipients, subject line, and even the message list.

While we’re going to focus on changing the actual font size, it should be noted that users can also easily change the font family or face as well. From a readability standpoint, it’s the font size that most users may find improves their Mail app experience.

How to Adjust the Font Size of Mail App in Mac OS X

This can be used to adjust the font sizes in Mail app either down or up, and the process is the same regardless of which version of Mac OS is installed on the Mac.

1. Open Mail app if you haven’t done so already
2. Optional but recommended: select / open an email message to see a live preview of the changed mail font size for
3. Pull down the “Mail” menu and select “Preferences”
4. Choose the “Fonts & Colors” tab and adjust the following:

• To change email message font size: Alongside “Message Font”, click the ‘Select’ button and then use the Size indicator to increase or decrease the font size – the default is size 12
• To change email inbox list font size: Click the “Select” button next to ‘Message list font’ and adjust the size as desired

A change in font size can make a considerable difference in readability in either direction, this is particularly true if a users eyesight isn’t perfect or even if you’re just trying to avoid eyestrain and spend a lot of time sending and receiving emails.

For example, here’s an email message in Mail app for MacOS and Mac OS X with the default font size:

And here’s the same email message in the Mac Mail app with a font size increased to size 18:

While that may look too large for some users, it may be perfect for others, it really depends on user preference, and the screen size of the display in use. This is specific to the actual Mail app in Mac OS X, meaning if your default email client is set to something else, or even to webmail, you’d need to adjust those settings separately. For web mail users like Gmail, Yahoo, and Hotmail, simply increasing the browsers text size with a zoom keystroke is typically sufficient.

This obviously covers the Mac side of things, and remember that iPad and iPhone users can also change the mail text size on iOS to accommodate their preferences.

Keyboard Shortcuts for Increasing & Decreasing Font Size in Mail for Mac

It’s worth mentioning that you can also change the font size of emails you are actively composing by using the ‘Format’ menu in Mail app too, and there are two handy keyboard shortcuts for increasing and decreasing Mail font size using the Formats menu:

In a new Mail composition window, or when replying or forwarding an email, click into the body of the email message and then use the following keystrokes to increase or decrease font size of the email:

• Command + to increase font size
• Command – to decrease font size

You can also access those formatting options from the ‘Format’ menu within Mail app. These keystrokes are found in many other places in Mac OS for increasing and decreasing font size, including Safari, so they may already be familiar to you.