The quickest way to make text bigger or smaller
You can change the font size on your iPhone in two places: the system-wide setting that affects most apps, and individual app settings for apps that let you control their own text size. The system setting is in the Accessibility menu under Display & Text Size, and it takes about 30 seconds to adjust. Most apps—Mail, Messages, Notes, Safari—will respect this change when ready. Some apps like Kindle or social media platforms have their own text size controls that override the system setting.
The fastest route depends on what you're trying to do. If you want bigger text everywhere on your phone, use the system setting. If only one app's text is too small, check that app's own settings first—you'll usually find it in the app's menu under Settings or Display.
Key Takeaways
- Go to Settings > Accessibility > Display & Text Size > Larger Accessibility Sizes to make system-wide text bigger or smaller across most apps.
- The slider in Display & Text Size goes from smallest to largest in seven steps, and you can preview the change before you confirm it.
- Individual apps like Mail, Messages, and Safari have their own text size controls in their settings menus, separate from the system setting.
- If an app ignores the system text size, open that app's settings and look for Display, Text Size, or Font options.
Change text size system-wide through Accessibility settings
Open Settings on your home screen, then tap Accessibility. Scroll down and tap Display & Text Size. You'll see a slider with a small "A" on the left and a large "A" on the right. Drag the slider left to make text smaller or right to make it larger. The preview text above the slider updates as you move it, so you can see the change before you lock it in. When the size looks right, tap the back arrow or swipe left to return to the Accessibility menu—your change saves automatically.
This setting affects the system font in Mail, Messages, Notes, Reminders, Calendar, Contacts, Health, Stocks, and most other built-in apps. It does not affect text inside web pages (Safari has its own control) or text in apps that use their own custom fonts. The change takes effect when ready, and you can adjust it again anytime.
Use Larger Accessibility Sizes for even bigger text
If the standard slider does not go large enough, turn on Larger Accessibility Sizes. In the same Display & Text Size menu, scroll down and toggle on the switch next to "Larger Accessibility Sizes." This unlocks four additional sizes beyond the standard seven, making text much larger across compatible apps. The preview updates to show you the biggest option available.
Larger Accessibility Sizes is designed for people with low vision, but anyone can use it. Be aware that very large text can make some app layouts awkward—buttons may move off-screen or text may overlap. If that happens, you can turn the toggle off or move the slider back to a smaller size.
Adjust text size in individual apps
Many apps have their own text size controls that work independently of the system setting. Open the app, then look for a Settings, Menu, or gear icon. In Mail, tap the three lines (menu icon) at the bottom right, then Settings, then your email account, then scroll down to find Text Size. In Safari, tap the "aA" icon at the top of the page and use the slider to adjust text size for that webpage only—the change applies only to that page, not all pages.
In Messages, go to Settings > Messages > Text Size. In Notes, open a note, tap the three dots at the top right, then select Text Size. In Kindle, open a book, tap the middle of the screen, tap the "aA" icon, and drag the slider. If you do not see a text size option in an app's settings, that app may not support it, or the control might be hidden in a different menu—check the app's help section or support page.
Change font size on web pages in Safari
Safari has its own text size control separate from the system setting. Open a webpage, tap the "aA" icon at the top of the screen (it appears next to the address bar), then drag the slider left to shrink text or right to enlarge it. This change applies only to that webpage. If you close Safari and return later, the page will use the default size again unless you adjust it again.
If you want a permanent change to all webpages in Safari, go to Settings > Safari > Page Zoom and set a default zoom level. This zoom applies to all pages you visit in Safari going forward, though individual pages may override it if they have fixed layouts.
Troubleshoot when text size does not change
If you adjusted the system text size and nothing changed, the app you're using may have its own text size setting that overrides it. Open that app's settings and look for Display, Text, Font, or Appearance options. Some apps like social media platforms or news readers ignore the system setting entirely and only respond to their own controls.
If the system slider itself is not working, restart your iPhone: press and hold the side button and either volume button until the power-off slider appears, drag it to turn off the phone, wait 10 seconds, then press and hold the side button again until the Apple logo appears. After the restart, go back to Settings > Accessibility > Display & Text Size and try adjusting the slider again. If it still does not work, the Accessibility menu itself may have a temporary glitch—restarting usually fixes it.
Frequently Asked Questions
Does changing the system text size affect all apps?
No. Built-in apps like Mail, Messages, Notes, and Calendar respect the system text size. Third-party apps like Instagram, Twitter, Kindle, and most news apps use their own fonts and ignore the system setting. Check each app's settings for its own text size control.
Can I make text bigger just on my lock screen?
The system text size does not affect the lock screen. To make the time and notifications on your lock screen larger, go to Settings > Accessibility > Display & Text Size and enable Larger Accessibility Sizes, which may increase some lock screen elements. Otherwise, lock screen text size is fixed.
What is the difference between the text size slider and Larger Accessibility Sizes?
The standard slider offers seven sizes. Larger Accessibility Sizes adds four extra-large sizes on top of that. Use the slider for everyday adjustments, and turn on Larger Accessibility Sizes only if you need text much larger than the slider provides.
If I change the text size, will it affect my battery life?
No. Changing text size does not use more or less battery. The size of the text displayed on screen does not change how much power your phone uses.
Can I set different text sizes for different apps?
The system text size applies to all compatible apps at once. You cannot set one size for Mail and a different size for Messages through the system setting. However, you can use the system setting for most apps and then adjust individual apps that have their own text size controls.