Where you can change fonts depends on what you're working with

Fonts can be changed in three main places: inside documents and apps you're using, in your operating system settings to affect everything on screen, or by installing new fonts your computer can access. Which one you need depends on whether you want to change text in a single document, make your whole screen easier to read, or add new typefaces to your system. Most people start by changing fonts within the specific program they're using — that's the quickest way if you only need one document to look different.

The steps differ between Windows, Mac, iPhone, and Android, and they also differ between programs like Microsoft Word, Google Docs, or email clients. This guide covers the most common scenarios: changing fonts in documents, adjusting system-wide text size and style, and adding new fonts to your computer.

Key Takeaways

  • In most document programs, you select the text first, then use the font menu in the toolbar to pick a new typeface.
  • Windows and Mac both let you change the default font size system-wide in accessibility settings, which affects menus, notifications, and some apps.
  • Installing new fonts on Windows means downloading a file and moving it to the Fonts folder; on Mac, you use Font Book.
  • On phones, you can usually only change fonts within individual apps — system-wide font changes are limited on iPhone and Android.
  • Google Docs and Microsoft 365 online let you change fonts the same way as the desktop versions, using the toolbar menu.

Changing fonts in Microsoft Word and Google Docs

In Microsoft Word on Windows or Mac, open your document and highlight the text you want to change. Look at the toolbar near the top — you'll see a dropdown menu that shows the current font name (often "Calibri" or "Arial" by default). Click that dropdown and you'll see a list of available fonts. Click the one you want and the selected text changes immediately.

If you want to change the font for text you haven't written yet, position your cursor where you want to type, select the new font from the dropdown, and start typing. To change the default font for all new documents in Word, go to File > Options > Advanced, scroll down to "Show document content", and change the default font there.

Google Docs works the same way. Open your document, highlight the text, and click the font dropdown in the toolbar (it usually says "Arial" by default). Select a new font from the list. Google Docs also lets you upload custom fonts: click the dropdown, scroll to the bottom, and select "More fonts" to browse Google's library or upload your own.

Changing fonts in email and other programs

In Gmail, compose a new email and look for the formatting toolbar below the subject line. Click the font dropdown (it may show as "Sans Serif" or a font name) to change the typeface for that email. The same toolbar has options for size, bold, italic, and color.

In Outlook on Windows, compose a new email and use the font dropdown in the Message tab of the ribbon at the top. On Mac, the font menu is in the toolbar. Most other programs that let you write or format text — including Apple Mail, Thunderbird, and Slack — have a similar font dropdown in their compose or formatting area. Look for a menu that shows a font name or a small "A" icon.

Adjusting text size system-wide on Windows

If you want to make text larger or smaller across your entire screen — in menus, notifications, and many apps — Windows lets you change the display scaling. Right-click on your desktop and select "Display settings". Scroll down to "Scale and layout" and look for "Change the size of text, apps, and other items". The default is 100%. You can increase it to 125%, 150%, or higher. Windows will ask you to sign out and back in for the change to take full effect.

For even more control, scroll down in the same Display settings window to "Advanced scaling settings". You can turn on "Let Windows try to fix apps so they're not blurry" if scaling makes some programs look fuzzy. This setting helps, though some older programs may still display oddly at higher scales.

Adjusting text size system-wide on Mac

On Mac, go to System Settings (or System Preferences on older versions) and click "Accessibility". Select "Display" from the left sidebar. You'll see a slider for "Text size" — drag it to the right to make text larger throughout your system. This affects menus, notifications, and many apps, though not all programs respect this setting.

Mac also has a "Increase contrast" option in the same Accessibility > Display section, which can make text easier to read. If you want to change the font used in menus and system text, that's more limited on Mac — the system uses San Francisco by default and doesn't offer an easy way to change it globally. You can only change fonts within individual applications.

Installing new fonts on Windows

To add new fonts to Windows, first download a font file from a website like Google Fonts, DaFont, or Font Squirrel. The file will usually be a .ttf or .otf file. Right-click the downloaded font file and select "Install". Windows will copy it to your Fonts folder automatically, and the font will be available in Word, Outlook, and other programs within a few seconds.

If you have multiple font files in a folder, you can select them all at once, right-click, and install them together. To see all your installed fonts, open Settings, go to Personalization > Fonts, and scroll through the list. You can also open the Fonts folder directly by typing "Fonts" into the Windows search bar and clicking "Fonts folder".

Installing new fonts on Mac

On Mac, download a font file (.ttf or .otf) and double-click it. Font Book will open automatically. Click "Install Font" in the dialog that appears, and the font is added to your system. It will be available in Word, Google Docs, and other programs right away.

To manage your fonts, open Font Book (search for it in Spotlight or find it in Applications > Utilities). You can see all installed fonts, disable ones you don't use, and organize them into collections. If a font isn't working in a specific program, try disabling it in Font Book and re-enabling it — sometimes this fixes compatibility issues.

Changing fonts on iPhone and Android

On iPhone, system-wide font changes are very limited. You can adjust text size in Settings > Accessibility > Display & Text Size, but this only affects the size, not the typeface itself. Individual apps like Notes, Mail, and Word have their own font options within the app — look for a formatting menu or settings button. Many third-party apps don't offer font changes at all.

On Android, the options vary by phone manufacturer. On most Android phones, go to Settings > Accessibility > Text and display, where you can adjust text size and sometimes font style. Some phones let you change the system font in Settings > Display > Font, though this option isn't available on all devices. Like iPhone, individual apps have their own font settings that you access within the app itself.

Frequently Asked Questions

Why don't I see the font I installed?

On Windows, restart the program you're using — it may not have reloaded the font list yet. On Mac, try disabling and re-enabling the font in Font Book. If the font still doesn't appear, make sure it's a standard .ttf or .otf file; some fonts are corrupted or in unsupported formats.

Can I change the default font for all my documents at once?

In Word, yes — go to File > Options > Advanced, find "Show document content", and change the default font there. This affects all new documents you create. In Google Docs, you can change the font for the current document, but there's no global default setting across all your docs.

What's the difference between a serif and sans-serif font?

Serif fonts have small lines at the ends of letters (like Times New Roman). Sans-serif fonts don't (like Arial or Helvetica). Sans-serif fonts are often considered easier to read on screens, while serif fonts are traditional for printed books. The choice is mostly about preference and readability for your audience.

Do I need to download fonts, or can I use what's already on my computer?

Windows and Mac come with dozens of fonts pre-installed. You only need to download new ones if you want a typeface that isn't already there. Check what's available in your program's font menu before downloading anything.

Will changing my system font size make everything blurry?

On Windows, some older programs may look blurry at higher scales. Use the "Let Windows try to fix apps so they're not blurry" option in Display settings to help. On Mac, scaling is handled more smoothly and rarely causes blurriness, but some very old programs may not scale properly.